Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* i2c-core.c - a device driver for the iic-bus interface */ |
2 | /* ------------------------------------------------------------------------- */ | |
3 | /* Copyright (C) 1995-99 Simon G. Vogl | |
4 | ||
5 | This program is free software; you can redistribute it and/or modify | |
6 | it under the terms of the GNU General Public License as published by | |
7 | the Free Software Foundation; either version 2 of the License, or | |
8 | (at your option) any later version. | |
9 | ||
10 | This program is distributed in the hope that it will be useful, | |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
ca1f8da9 | 13 | GNU General Public License for more details. */ |
1da177e4 LT |
14 | /* ------------------------------------------------------------------------- */ |
15 | ||
96de0e25 | 16 | /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>. |
1da177e4 | 17 | All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl> |
421ef47b | 18 | SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and |
7c81c60f | 19 | Jean Delvare <jdelvare@suse.de> |
0826374b | 20 | Mux support by Rodolfo Giometti <giometti@enneenne.com> and |
687b81d0 WS |
21 | Michael Lawnick <michael.lawnick.ext@nsn.com> |
22 | OF support is copyright (c) 2008 Jochen Friedrich <jochen@scram.de> | |
23 | (based on a previous patch from Jon Smirl <jonsmirl@gmail.com>) and | |
24 | (c) 2013 Wolfram Sang <wsa@the-dreams.de> | |
17f4a5c4 WS |
25 | I2C ACPI code Copyright (C) 2014 Intel Corp |
26 | Author: Lan Tianyu <tianyu.lan@intel.com> | |
4b1acc43 | 27 | I2C slave support (c) 2014 by Wolfram Sang <wsa@sang-engineering.com> |
687b81d0 | 28 | */ |
1da177e4 | 29 | |
b4e2f6ac | 30 | #include <dt-bindings/i2c/i2c.h> |
1da177e4 LT |
31 | #include <linux/module.h> |
32 | #include <linux/kernel.h> | |
5f9296ba | 33 | #include <linux/delay.h> |
1da177e4 | 34 | #include <linux/errno.h> |
5f9296ba | 35 | #include <linux/gpio.h> |
1da177e4 LT |
36 | #include <linux/slab.h> |
37 | #include <linux/i2c.h> | |
38 | #include <linux/init.h> | |
39 | #include <linux/idr.h> | |
b3585e4f | 40 | #include <linux/mutex.h> |
687b81d0 | 41 | #include <linux/of.h> |
959e85f7 | 42 | #include <linux/of_device.h> |
687b81d0 | 43 | #include <linux/of_irq.h> |
86be408b | 44 | #include <linux/clk/clk-conf.h> |
b8d6f45b | 45 | #include <linux/completion.h> |
cea443a8 MR |
46 | #include <linux/hardirq.h> |
47 | #include <linux/irqflags.h> | |
f18c41da | 48 | #include <linux/rwsem.h> |
6de468ae | 49 | #include <linux/pm_runtime.h> |
f48c767c | 50 | #include <linux/pm_domain.h> |
3fffd128 | 51 | #include <linux/pm_wakeirq.h> |
907ddf89 | 52 | #include <linux/acpi.h> |
d9a83d62 | 53 | #include <linux/jump_label.h> |
1da177e4 | 54 | #include <asm/uaccess.h> |
a430a345 | 55 | #include <linux/err.h> |
e1dba01c | 56 | #include <linux/property.h> |
1da177e4 | 57 | |
9c1600ed DB |
58 | #include "i2c-core.h" |
59 | ||
d9a83d62 DH |
60 | #define CREATE_TRACE_POINTS |
61 | #include <trace/events/i2c.h> | |
1da177e4 | 62 | |
da899f55 WS |
63 | #define I2C_ADDR_OFFSET_TEN_BIT 0xa000 |
64 | #define I2C_ADDR_OFFSET_SLAVE 0x1000 | |
65 | ||
6629dcff | 66 | /* core_lock protects i2c_adapter_idr, and guarantees |
35fc37f8 | 67 | that device detection, deletion of detected devices, and attach_adapter |
19baba4c | 68 | calls are serialized */ |
caada32a | 69 | static DEFINE_MUTEX(core_lock); |
1da177e4 LT |
70 | static DEFINE_IDR(i2c_adapter_idr); |
71 | ||
4f8cf824 | 72 | static struct device_type i2c_client_type; |
4735c98f | 73 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver); |
f37dd80a | 74 | |
d9a83d62 DH |
75 | static struct static_key i2c_trace_msg = STATIC_KEY_INIT_FALSE; |
76 | ||
77 | void i2c_transfer_trace_reg(void) | |
78 | { | |
79 | static_key_slow_inc(&i2c_trace_msg); | |
80 | } | |
81 | ||
82 | void i2c_transfer_trace_unreg(void) | |
83 | { | |
84 | static_key_slow_dec(&i2c_trace_msg); | |
85 | } | |
86 | ||
17f4a5c4 WS |
87 | #if defined(CONFIG_ACPI) |
88 | struct acpi_i2c_handler_data { | |
89 | struct acpi_connection_info info; | |
90 | struct i2c_adapter *adapter; | |
91 | }; | |
92 | ||
93 | struct gsb_buffer { | |
94 | u8 status; | |
95 | u8 len; | |
96 | union { | |
97 | u16 wdata; | |
98 | u8 bdata; | |
99 | u8 data[0]; | |
100 | }; | |
101 | } __packed; | |
102 | ||
166c2ba3 MW |
103 | struct acpi_i2c_lookup { |
104 | struct i2c_board_info *info; | |
105 | acpi_handle adapter_handle; | |
106 | acpi_handle device_handle; | |
107 | }; | |
17f4a5c4 | 108 | |
166c2ba3 MW |
109 | static int acpi_i2c_find_address(struct acpi_resource *ares, void *data) |
110 | { | |
111 | struct acpi_i2c_lookup *lookup = data; | |
112 | struct i2c_board_info *info = lookup->info; | |
113 | struct acpi_resource_i2c_serialbus *sb; | |
114 | acpi_handle adapter_handle; | |
115 | acpi_status status; | |
17f4a5c4 | 116 | |
166c2ba3 MW |
117 | if (info->addr || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) |
118 | return 1; | |
119 | ||
120 | sb = &ares->data.i2c_serial_bus; | |
121 | if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) | |
122 | return 1; | |
123 | ||
124 | /* | |
125 | * Extract the ResourceSource and make sure that the handle matches | |
126 | * with the I2C adapter handle. | |
127 | */ | |
128 | status = acpi_get_handle(lookup->device_handle, | |
129 | sb->resource_source.string_ptr, | |
130 | &adapter_handle); | |
131 | if (ACPI_SUCCESS(status) && adapter_handle == lookup->adapter_handle) { | |
132 | info->addr = sb->slave_address; | |
133 | if (sb->access_mode == ACPI_I2C_10BIT_MODE) | |
134 | info->flags |= I2C_CLIENT_TEN; | |
17f4a5c4 WS |
135 | } |
136 | ||
17f4a5c4 WS |
137 | return 1; |
138 | } | |
139 | ||
140 | static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level, | |
141 | void *data, void **return_value) | |
142 | { | |
143 | struct i2c_adapter *adapter = data; | |
144 | struct list_head resource_list; | |
166c2ba3 MW |
145 | struct acpi_i2c_lookup lookup; |
146 | struct resource_entry *entry; | |
17f4a5c4 WS |
147 | struct i2c_board_info info; |
148 | struct acpi_device *adev; | |
149 | int ret; | |
150 | ||
151 | if (acpi_bus_get_device(handle, &adev)) | |
152 | return AE_OK; | |
153 | if (acpi_bus_get_status(adev) || !adev->status.present) | |
154 | return AE_OK; | |
155 | ||
156 | memset(&info, 0, sizeof(info)); | |
ce793486 | 157 | info.fwnode = acpi_fwnode_handle(adev); |
17f4a5c4 | 158 | |
166c2ba3 | 159 | memset(&lookup, 0, sizeof(lookup)); |
8eb5c87a | 160 | lookup.adapter_handle = ACPI_HANDLE(&adapter->dev); |
166c2ba3 MW |
161 | lookup.device_handle = handle; |
162 | lookup.info = &info; | |
163 | ||
164 | /* | |
165 | * Look up for I2cSerialBus resource with ResourceSource that | |
166 | * matches with this adapter. | |
167 | */ | |
17f4a5c4 WS |
168 | INIT_LIST_HEAD(&resource_list); |
169 | ret = acpi_dev_get_resources(adev, &resource_list, | |
166c2ba3 | 170 | acpi_i2c_find_address, &lookup); |
17f4a5c4 WS |
171 | acpi_dev_free_resource_list(&resource_list); |
172 | ||
173 | if (ret < 0 || !info.addr) | |
174 | return AE_OK; | |
175 | ||
166c2ba3 MW |
176 | /* Then fill IRQ number if any */ |
177 | ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL); | |
178 | if (ret < 0) | |
179 | return AE_OK; | |
180 | ||
181 | resource_list_for_each_entry(entry, &resource_list) { | |
182 | if (resource_type(entry->res) == IORESOURCE_IRQ) { | |
183 | info.irq = entry->res->start; | |
184 | break; | |
185 | } | |
186 | } | |
187 | ||
188 | acpi_dev_free_resource_list(&resource_list); | |
189 | ||
17f4a5c4 WS |
190 | adev->power.flags.ignore_parent = true; |
191 | strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type)); | |
192 | if (!i2c_new_device(adapter, &info)) { | |
193 | adev->power.flags.ignore_parent = false; | |
194 | dev_err(&adapter->dev, | |
195 | "failed to add I2C device %s from ACPI\n", | |
196 | dev_name(&adev->dev)); | |
197 | } | |
198 | ||
199 | return AE_OK; | |
200 | } | |
201 | ||
166c2ba3 MW |
202 | #define ACPI_I2C_MAX_SCAN_DEPTH 32 |
203 | ||
17f4a5c4 WS |
204 | /** |
205 | * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter | |
206 | * @adap: pointer to adapter | |
207 | * | |
208 | * Enumerate all I2C slave devices behind this adapter by walking the ACPI | |
209 | * namespace. When a device is found it will be added to the Linux device | |
210 | * model and bound to the corresponding ACPI handle. | |
211 | */ | |
212 | static void acpi_i2c_register_devices(struct i2c_adapter *adap) | |
213 | { | |
17f4a5c4 WS |
214 | acpi_status status; |
215 | ||
8eb5c87a | 216 | if (!has_acpi_companion(&adap->dev)) |
17f4a5c4 WS |
217 | return; |
218 | ||
166c2ba3 MW |
219 | status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, |
220 | ACPI_I2C_MAX_SCAN_DEPTH, | |
17f4a5c4 WS |
221 | acpi_i2c_add_device, NULL, |
222 | adap, NULL); | |
223 | if (ACPI_FAILURE(status)) | |
224 | dev_warn(&adap->dev, "failed to enumerate I2C slaves\n"); | |
225 | } | |
226 | ||
227 | #else /* CONFIG_ACPI */ | |
228 | static inline void acpi_i2c_register_devices(struct i2c_adapter *adap) { } | |
229 | #endif /* CONFIG_ACPI */ | |
230 | ||
231 | #ifdef CONFIG_ACPI_I2C_OPREGION | |
232 | static int acpi_gsb_i2c_read_bytes(struct i2c_client *client, | |
233 | u8 cmd, u8 *data, u8 data_len) | |
234 | { | |
235 | ||
236 | struct i2c_msg msgs[2]; | |
237 | int ret; | |
238 | u8 *buffer; | |
239 | ||
240 | buffer = kzalloc(data_len, GFP_KERNEL); | |
241 | if (!buffer) | |
242 | return AE_NO_MEMORY; | |
243 | ||
244 | msgs[0].addr = client->addr; | |
245 | msgs[0].flags = client->flags; | |
246 | msgs[0].len = 1; | |
247 | msgs[0].buf = &cmd; | |
248 | ||
249 | msgs[1].addr = client->addr; | |
250 | msgs[1].flags = client->flags | I2C_M_RD; | |
251 | msgs[1].len = data_len; | |
252 | msgs[1].buf = buffer; | |
253 | ||
254 | ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); | |
255 | if (ret < 0) | |
256 | dev_err(&client->adapter->dev, "i2c read failed\n"); | |
257 | else | |
258 | memcpy(data, buffer, data_len); | |
259 | ||
260 | kfree(buffer); | |
261 | return ret; | |
262 | } | |
263 | ||
264 | static int acpi_gsb_i2c_write_bytes(struct i2c_client *client, | |
265 | u8 cmd, u8 *data, u8 data_len) | |
266 | { | |
267 | ||
268 | struct i2c_msg msgs[1]; | |
269 | u8 *buffer; | |
270 | int ret = AE_OK; | |
271 | ||
272 | buffer = kzalloc(data_len + 1, GFP_KERNEL); | |
273 | if (!buffer) | |
274 | return AE_NO_MEMORY; | |
275 | ||
276 | buffer[0] = cmd; | |
277 | memcpy(buffer + 1, data, data_len); | |
278 | ||
279 | msgs[0].addr = client->addr; | |
280 | msgs[0].flags = client->flags; | |
281 | msgs[0].len = data_len + 1; | |
282 | msgs[0].buf = buffer; | |
283 | ||
284 | ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); | |
285 | if (ret < 0) | |
286 | dev_err(&client->adapter->dev, "i2c write failed\n"); | |
287 | ||
288 | kfree(buffer); | |
289 | return ret; | |
290 | } | |
291 | ||
292 | static acpi_status | |
293 | acpi_i2c_space_handler(u32 function, acpi_physical_address command, | |
294 | u32 bits, u64 *value64, | |
295 | void *handler_context, void *region_context) | |
296 | { | |
297 | struct gsb_buffer *gsb = (struct gsb_buffer *)value64; | |
298 | struct acpi_i2c_handler_data *data = handler_context; | |
299 | struct acpi_connection_info *info = &data->info; | |
300 | struct acpi_resource_i2c_serialbus *sb; | |
301 | struct i2c_adapter *adapter = data->adapter; | |
7ef85f5f | 302 | struct i2c_client *client; |
17f4a5c4 WS |
303 | struct acpi_resource *ares; |
304 | u32 accessor_type = function >> 16; | |
305 | u8 action = function & ACPI_IO_MASK; | |
4470c725 | 306 | acpi_status ret; |
17f4a5c4 WS |
307 | int status; |
308 | ||
309 | ret = acpi_buffer_to_resource(info->connection, info->length, &ares); | |
310 | if (ACPI_FAILURE(ret)) | |
311 | return ret; | |
312 | ||
7ef85f5f JN |
313 | client = kzalloc(sizeof(*client), GFP_KERNEL); |
314 | if (!client) { | |
315 | ret = AE_NO_MEMORY; | |
316 | goto err; | |
317 | } | |
318 | ||
17f4a5c4 WS |
319 | if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) { |
320 | ret = AE_BAD_PARAMETER; | |
321 | goto err; | |
322 | } | |
323 | ||
324 | sb = &ares->data.i2c_serial_bus; | |
325 | if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) { | |
326 | ret = AE_BAD_PARAMETER; | |
327 | goto err; | |
328 | } | |
329 | ||
7ef85f5f JN |
330 | client->adapter = adapter; |
331 | client->addr = sb->slave_address; | |
17f4a5c4 WS |
332 | |
333 | if (sb->access_mode == ACPI_I2C_10BIT_MODE) | |
7ef85f5f | 334 | client->flags |= I2C_CLIENT_TEN; |
17f4a5c4 WS |
335 | |
336 | switch (accessor_type) { | |
337 | case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV: | |
338 | if (action == ACPI_READ) { | |
7ef85f5f | 339 | status = i2c_smbus_read_byte(client); |
17f4a5c4 WS |
340 | if (status >= 0) { |
341 | gsb->bdata = status; | |
342 | status = 0; | |
343 | } | |
344 | } else { | |
7ef85f5f | 345 | status = i2c_smbus_write_byte(client, gsb->bdata); |
17f4a5c4 WS |
346 | } |
347 | break; | |
348 | ||
349 | case ACPI_GSB_ACCESS_ATTRIB_BYTE: | |
350 | if (action == ACPI_READ) { | |
7ef85f5f | 351 | status = i2c_smbus_read_byte_data(client, command); |
17f4a5c4 WS |
352 | if (status >= 0) { |
353 | gsb->bdata = status; | |
354 | status = 0; | |
355 | } | |
356 | } else { | |
7ef85f5f | 357 | status = i2c_smbus_write_byte_data(client, command, |
17f4a5c4 WS |
358 | gsb->bdata); |
359 | } | |
360 | break; | |
361 | ||
362 | case ACPI_GSB_ACCESS_ATTRIB_WORD: | |
363 | if (action == ACPI_READ) { | |
7ef85f5f | 364 | status = i2c_smbus_read_word_data(client, command); |
17f4a5c4 WS |
365 | if (status >= 0) { |
366 | gsb->wdata = status; | |
367 | status = 0; | |
368 | } | |
369 | } else { | |
7ef85f5f | 370 | status = i2c_smbus_write_word_data(client, command, |
17f4a5c4 WS |
371 | gsb->wdata); |
372 | } | |
373 | break; | |
374 | ||
375 | case ACPI_GSB_ACCESS_ATTRIB_BLOCK: | |
376 | if (action == ACPI_READ) { | |
7ef85f5f | 377 | status = i2c_smbus_read_block_data(client, command, |
17f4a5c4 WS |
378 | gsb->data); |
379 | if (status >= 0) { | |
380 | gsb->len = status; | |
381 | status = 0; | |
382 | } | |
383 | } else { | |
7ef85f5f | 384 | status = i2c_smbus_write_block_data(client, command, |
17f4a5c4 WS |
385 | gsb->len, gsb->data); |
386 | } | |
387 | break; | |
388 | ||
389 | case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE: | |
390 | if (action == ACPI_READ) { | |
7ef85f5f | 391 | status = acpi_gsb_i2c_read_bytes(client, command, |
17f4a5c4 WS |
392 | gsb->data, info->access_length); |
393 | if (status > 0) | |
394 | status = 0; | |
395 | } else { | |
7ef85f5f | 396 | status = acpi_gsb_i2c_write_bytes(client, command, |
17f4a5c4 WS |
397 | gsb->data, info->access_length); |
398 | } | |
399 | break; | |
400 | ||
401 | default: | |
402 | pr_info("protocol(0x%02x) is not supported.\n", accessor_type); | |
403 | ret = AE_BAD_PARAMETER; | |
404 | goto err; | |
405 | } | |
406 | ||
407 | gsb->status = status; | |
408 | ||
409 | err: | |
7ef85f5f | 410 | kfree(client); |
17f4a5c4 WS |
411 | ACPI_FREE(ares); |
412 | return ret; | |
413 | } | |
414 | ||
415 | ||
416 | static int acpi_i2c_install_space_handler(struct i2c_adapter *adapter) | |
417 | { | |
0aef44e8 | 418 | acpi_handle handle; |
17f4a5c4 WS |
419 | struct acpi_i2c_handler_data *data; |
420 | acpi_status status; | |
421 | ||
0aef44e8 PH |
422 | if (!adapter->dev.parent) |
423 | return -ENODEV; | |
424 | ||
425 | handle = ACPI_HANDLE(adapter->dev.parent); | |
426 | ||
17f4a5c4 WS |
427 | if (!handle) |
428 | return -ENODEV; | |
429 | ||
430 | data = kzalloc(sizeof(struct acpi_i2c_handler_data), | |
431 | GFP_KERNEL); | |
432 | if (!data) | |
433 | return -ENOMEM; | |
434 | ||
435 | data->adapter = adapter; | |
436 | status = acpi_bus_attach_private_data(handle, (void *)data); | |
437 | if (ACPI_FAILURE(status)) { | |
438 | kfree(data); | |
439 | return -ENOMEM; | |
440 | } | |
441 | ||
442 | status = acpi_install_address_space_handler(handle, | |
443 | ACPI_ADR_SPACE_GSBUS, | |
444 | &acpi_i2c_space_handler, | |
445 | NULL, | |
446 | data); | |
447 | if (ACPI_FAILURE(status)) { | |
448 | dev_err(&adapter->dev, "Error installing i2c space handler\n"); | |
449 | acpi_bus_detach_private_data(handle); | |
450 | kfree(data); | |
451 | return -ENOMEM; | |
452 | } | |
453 | ||
40e7fcb1 | 454 | acpi_walk_dep_device_list(handle); |
17f4a5c4 WS |
455 | return 0; |
456 | } | |
457 | ||
458 | static void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter) | |
459 | { | |
0aef44e8 | 460 | acpi_handle handle; |
17f4a5c4 WS |
461 | struct acpi_i2c_handler_data *data; |
462 | acpi_status status; | |
463 | ||
0aef44e8 PH |
464 | if (!adapter->dev.parent) |
465 | return; | |
466 | ||
467 | handle = ACPI_HANDLE(adapter->dev.parent); | |
468 | ||
17f4a5c4 WS |
469 | if (!handle) |
470 | return; | |
471 | ||
472 | acpi_remove_address_space_handler(handle, | |
473 | ACPI_ADR_SPACE_GSBUS, | |
474 | &acpi_i2c_space_handler); | |
475 | ||
476 | status = acpi_bus_get_private_data(handle, (void **)&data); | |
477 | if (ACPI_SUCCESS(status)) | |
478 | kfree(data); | |
479 | ||
480 | acpi_bus_detach_private_data(handle); | |
481 | } | |
482 | #else /* CONFIG_ACPI_I2C_OPREGION */ | |
483 | static inline void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter) | |
484 | { } | |
485 | ||
486 | static inline int acpi_i2c_install_space_handler(struct i2c_adapter *adapter) | |
487 | { return 0; } | |
488 | #endif /* CONFIG_ACPI_I2C_OPREGION */ | |
489 | ||
f37dd80a DB |
490 | /* ------------------------------------------------------------------------- */ |
491 | ||
d2653e92 JD |
492 | static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, |
493 | const struct i2c_client *client) | |
494 | { | |
495 | while (id->name[0]) { | |
496 | if (strcmp(client->name, id->name) == 0) | |
497 | return id; | |
498 | id++; | |
499 | } | |
500 | return NULL; | |
501 | } | |
502 | ||
1da177e4 LT |
503 | static int i2c_device_match(struct device *dev, struct device_driver *drv) |
504 | { | |
51298d12 JD |
505 | struct i2c_client *client = i2c_verify_client(dev); |
506 | struct i2c_driver *driver; | |
507 | ||
508 | if (!client) | |
509 | return 0; | |
7b4fbc50 | 510 | |
959e85f7 GL |
511 | /* Attempt an OF style match */ |
512 | if (of_driver_match_device(dev, drv)) | |
513 | return 1; | |
514 | ||
907ddf89 MW |
515 | /* Then ACPI style match */ |
516 | if (acpi_driver_match_device(dev, drv)) | |
517 | return 1; | |
518 | ||
51298d12 | 519 | driver = to_i2c_driver(drv); |
d2653e92 JD |
520 | /* match on an id table if there is one */ |
521 | if (driver->id_table) | |
522 | return i2c_match_id(driver->id_table, client) != NULL; | |
523 | ||
eb8a7908 | 524 | return 0; |
1da177e4 LT |
525 | } |
526 | ||
7b4fbc50 DB |
527 | |
528 | /* uevent helps with hotplug: modprobe -q $(MODALIAS) */ | |
7eff2e7a | 529 | static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env) |
7b4fbc50 DB |
530 | { |
531 | struct i2c_client *client = to_i2c_client(dev); | |
8c4ff6d0 ZR |
532 | int rc; |
533 | ||
534 | rc = acpi_device_uevent_modalias(dev, env); | |
535 | if (rc != -ENODEV) | |
536 | return rc; | |
7b4fbc50 | 537 | |
eb8a7908 JD |
538 | if (add_uevent_var(env, "MODALIAS=%s%s", |
539 | I2C_MODULE_PREFIX, client->name)) | |
540 | return -ENOMEM; | |
7b4fbc50 DB |
541 | dev_dbg(dev, "uevent\n"); |
542 | return 0; | |
543 | } | |
544 | ||
5f9296ba VK |
545 | /* i2c bus recovery routines */ |
546 | static int get_scl_gpio_value(struct i2c_adapter *adap) | |
547 | { | |
548 | return gpio_get_value(adap->bus_recovery_info->scl_gpio); | |
549 | } | |
550 | ||
551 | static void set_scl_gpio_value(struct i2c_adapter *adap, int val) | |
552 | { | |
553 | gpio_set_value(adap->bus_recovery_info->scl_gpio, val); | |
554 | } | |
555 | ||
556 | static int get_sda_gpio_value(struct i2c_adapter *adap) | |
557 | { | |
558 | return gpio_get_value(adap->bus_recovery_info->sda_gpio); | |
559 | } | |
560 | ||
561 | static int i2c_get_gpios_for_recovery(struct i2c_adapter *adap) | |
562 | { | |
563 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
564 | struct device *dev = &adap->dev; | |
565 | int ret = 0; | |
566 | ||
567 | ret = gpio_request_one(bri->scl_gpio, GPIOF_OPEN_DRAIN | | |
568 | GPIOF_OUT_INIT_HIGH, "i2c-scl"); | |
569 | if (ret) { | |
570 | dev_warn(dev, "Can't get SCL gpio: %d\n", bri->scl_gpio); | |
571 | return ret; | |
572 | } | |
573 | ||
574 | if (bri->get_sda) { | |
575 | if (gpio_request_one(bri->sda_gpio, GPIOF_IN, "i2c-sda")) { | |
576 | /* work without SDA polling */ | |
577 | dev_warn(dev, "Can't get SDA gpio: %d. Not using SDA polling\n", | |
578 | bri->sda_gpio); | |
579 | bri->get_sda = NULL; | |
580 | } | |
581 | } | |
582 | ||
583 | return ret; | |
584 | } | |
585 | ||
586 | static void i2c_put_gpios_for_recovery(struct i2c_adapter *adap) | |
587 | { | |
588 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
589 | ||
590 | if (bri->get_sda) | |
591 | gpio_free(bri->sda_gpio); | |
592 | ||
593 | gpio_free(bri->scl_gpio); | |
594 | } | |
595 | ||
596 | /* | |
597 | * We are generating clock pulses. ndelay() determines durating of clk pulses. | |
598 | * We will generate clock with rate 100 KHz and so duration of both clock levels | |
599 | * is: delay in ns = (10^6 / 100) / 2 | |
600 | */ | |
601 | #define RECOVERY_NDELAY 5000 | |
602 | #define RECOVERY_CLK_CNT 9 | |
603 | ||
604 | static int i2c_generic_recovery(struct i2c_adapter *adap) | |
605 | { | |
606 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
607 | int i = 0, val = 1, ret = 0; | |
608 | ||
609 | if (bri->prepare_recovery) | |
2b2190a3 | 610 | bri->prepare_recovery(adap); |
5f9296ba | 611 | |
8b062608 JL |
612 | bri->set_scl(adap, val); |
613 | ndelay(RECOVERY_NDELAY); | |
614 | ||
5f9296ba VK |
615 | /* |
616 | * By this time SCL is high, as we need to give 9 falling-rising edges | |
617 | */ | |
618 | while (i++ < RECOVERY_CLK_CNT * 2) { | |
619 | if (val) { | |
620 | /* Break if SDA is high */ | |
621 | if (bri->get_sda && bri->get_sda(adap)) | |
622 | break; | |
623 | /* SCL shouldn't be low here */ | |
624 | if (!bri->get_scl(adap)) { | |
625 | dev_err(&adap->dev, | |
626 | "SCL is stuck low, exit recovery\n"); | |
627 | ret = -EBUSY; | |
628 | break; | |
629 | } | |
630 | } | |
631 | ||
632 | val = !val; | |
633 | bri->set_scl(adap, val); | |
634 | ndelay(RECOVERY_NDELAY); | |
635 | } | |
636 | ||
637 | if (bri->unprepare_recovery) | |
2b2190a3 | 638 | bri->unprepare_recovery(adap); |
5f9296ba VK |
639 | |
640 | return ret; | |
641 | } | |
642 | ||
643 | int i2c_generic_scl_recovery(struct i2c_adapter *adap) | |
644 | { | |
5f9296ba VK |
645 | return i2c_generic_recovery(adap); |
646 | } | |
c1c21f4e | 647 | EXPORT_SYMBOL_GPL(i2c_generic_scl_recovery); |
5f9296ba VK |
648 | |
649 | int i2c_generic_gpio_recovery(struct i2c_adapter *adap) | |
650 | { | |
651 | int ret; | |
652 | ||
653 | ret = i2c_get_gpios_for_recovery(adap); | |
654 | if (ret) | |
655 | return ret; | |
656 | ||
657 | ret = i2c_generic_recovery(adap); | |
658 | i2c_put_gpios_for_recovery(adap); | |
659 | ||
660 | return ret; | |
661 | } | |
c1c21f4e | 662 | EXPORT_SYMBOL_GPL(i2c_generic_gpio_recovery); |
5f9296ba VK |
663 | |
664 | int i2c_recover_bus(struct i2c_adapter *adap) | |
665 | { | |
666 | if (!adap->bus_recovery_info) | |
667 | return -EOPNOTSUPP; | |
668 | ||
669 | dev_dbg(&adap->dev, "Trying i2c bus recovery\n"); | |
670 | return adap->bus_recovery_info->recover_bus(adap); | |
671 | } | |
c1c21f4e | 672 | EXPORT_SYMBOL_GPL(i2c_recover_bus); |
5f9296ba | 673 | |
f37dd80a | 674 | static int i2c_device_probe(struct device *dev) |
1da177e4 | 675 | { |
51298d12 JD |
676 | struct i2c_client *client = i2c_verify_client(dev); |
677 | struct i2c_driver *driver; | |
50c3304a | 678 | int status; |
7b4fbc50 | 679 | |
51298d12 JD |
680 | if (!client) |
681 | return 0; | |
682 | ||
845c8770 MW |
683 | if (!client->irq) { |
684 | int irq = -ENOENT; | |
685 | ||
3fffd128 DT |
686 | if (dev->of_node) { |
687 | irq = of_irq_get_byname(dev->of_node, "irq"); | |
688 | if (irq == -EINVAL || irq == -ENODATA) | |
689 | irq = of_irq_get(dev->of_node, 0); | |
690 | } else if (ACPI_COMPANION(dev)) { | |
845c8770 | 691 | irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(dev), 0); |
3fffd128 | 692 | } |
6f34be74 | 693 | if (irq == -EPROBE_DEFER) |
2fd36c55 | 694 | return irq; |
6f34be74 GU |
695 | if (irq < 0) |
696 | irq = 0; | |
2fd36c55 LP |
697 | |
698 | client->irq = irq; | |
699 | } | |
700 | ||
51298d12 | 701 | driver = to_i2c_driver(dev->driver); |
e0457442 | 702 | if (!driver->probe || !driver->id_table) |
7b4fbc50 | 703 | return -ENODEV; |
0acc2b32 | 704 | |
3fffd128 DT |
705 | if (client->flags & I2C_CLIENT_WAKE) { |
706 | int wakeirq = -ENOENT; | |
707 | ||
708 | if (dev->of_node) { | |
709 | wakeirq = of_irq_get_byname(dev->of_node, "wakeup"); | |
710 | if (wakeirq == -EPROBE_DEFER) | |
711 | return wakeirq; | |
712 | } | |
713 | ||
714 | device_init_wakeup(&client->dev, true); | |
715 | ||
716 | if (wakeirq > 0 && wakeirq != client->irq) | |
717 | status = dev_pm_set_dedicated_wake_irq(dev, wakeirq); | |
718 | else if (client->irq > 0) | |
c18fba23 | 719 | status = dev_pm_set_wake_irq(dev, client->irq); |
3fffd128 DT |
720 | else |
721 | status = 0; | |
722 | ||
723 | if (status) | |
724 | dev_warn(&client->dev, "failed to set up wakeup irq"); | |
725 | } | |
726 | ||
7b4fbc50 | 727 | dev_dbg(dev, "probe\n"); |
d2653e92 | 728 | |
86be408b SN |
729 | status = of_clk_set_defaults(dev->of_node, false); |
730 | if (status < 0) | |
3fffd128 | 731 | goto err_clear_wakeup_irq; |
86be408b | 732 | |
e09b0d4e | 733 | status = dev_pm_domain_attach(&client->dev, true); |
74cedd30 KB |
734 | if (status == -EPROBE_DEFER) |
735 | goto err_clear_wakeup_irq; | |
736 | ||
737 | status = driver->probe(client, i2c_match_id(driver->id_table, client)); | |
738 | if (status) | |
739 | goto err_detach_pm_domain; | |
72fa818e | 740 | |
3fffd128 DT |
741 | return 0; |
742 | ||
743 | err_detach_pm_domain: | |
744 | dev_pm_domain_detach(&client->dev, true); | |
745 | err_clear_wakeup_irq: | |
746 | dev_pm_clear_wake_irq(&client->dev); | |
747 | device_init_wakeup(&client->dev, false); | |
50c3304a | 748 | return status; |
f37dd80a | 749 | } |
1da177e4 | 750 | |
f37dd80a DB |
751 | static int i2c_device_remove(struct device *dev) |
752 | { | |
51298d12 | 753 | struct i2c_client *client = i2c_verify_client(dev); |
a1d9e6e4 | 754 | struct i2c_driver *driver; |
72fa818e | 755 | int status = 0; |
a1d9e6e4 | 756 | |
51298d12 | 757 | if (!client || !dev->driver) |
a1d9e6e4 DB |
758 | return 0; |
759 | ||
760 | driver = to_i2c_driver(dev->driver); | |
761 | if (driver->remove) { | |
762 | dev_dbg(dev, "remove\n"); | |
763 | status = driver->remove(client); | |
a1d9e6e4 | 764 | } |
72fa818e | 765 | |
e09b0d4e | 766 | dev_pm_domain_detach(&client->dev, true); |
3fffd128 DT |
767 | |
768 | dev_pm_clear_wake_irq(&client->dev); | |
769 | device_init_wakeup(&client->dev, false); | |
770 | ||
a1d9e6e4 | 771 | return status; |
1da177e4 LT |
772 | } |
773 | ||
f37dd80a | 774 | static void i2c_device_shutdown(struct device *dev) |
1da177e4 | 775 | { |
51298d12 | 776 | struct i2c_client *client = i2c_verify_client(dev); |
f37dd80a DB |
777 | struct i2c_driver *driver; |
778 | ||
51298d12 | 779 | if (!client || !dev->driver) |
f37dd80a DB |
780 | return; |
781 | driver = to_i2c_driver(dev->driver); | |
782 | if (driver->shutdown) | |
51298d12 | 783 | driver->shutdown(client); |
1da177e4 LT |
784 | } |
785 | ||
9c1600ed DB |
786 | static void i2c_client_dev_release(struct device *dev) |
787 | { | |
788 | kfree(to_i2c_client(dev)); | |
789 | } | |
790 | ||
09b8ce0a | 791 | static ssize_t |
4f8cf824 | 792 | show_name(struct device *dev, struct device_attribute *attr, char *buf) |
7b4fbc50 | 793 | { |
4f8cf824 JD |
794 | return sprintf(buf, "%s\n", dev->type == &i2c_client_type ? |
795 | to_i2c_client(dev)->name : to_i2c_adapter(dev)->name); | |
7b4fbc50 | 796 | } |
a5eb71b2 | 797 | static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); |
7b4fbc50 | 798 | |
09b8ce0a ZX |
799 | static ssize_t |
800 | show_modalias(struct device *dev, struct device_attribute *attr, char *buf) | |
7b4fbc50 DB |
801 | { |
802 | struct i2c_client *client = to_i2c_client(dev); | |
8c4ff6d0 ZR |
803 | int len; |
804 | ||
805 | len = acpi_device_modalias(dev, buf, PAGE_SIZE -1); | |
806 | if (len != -ENODEV) | |
807 | return len; | |
808 | ||
eb8a7908 | 809 | return sprintf(buf, "%s%s\n", I2C_MODULE_PREFIX, client->name); |
7b4fbc50 | 810 | } |
51298d12 JD |
811 | static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL); |
812 | ||
813 | static struct attribute *i2c_dev_attrs[] = { | |
814 | &dev_attr_name.attr, | |
7b4fbc50 | 815 | /* modalias helps coldplug: modprobe $(cat .../modalias) */ |
51298d12 JD |
816 | &dev_attr_modalias.attr, |
817 | NULL | |
818 | }; | |
a5eb71b2 | 819 | ATTRIBUTE_GROUPS(i2c_dev); |
54067ee2 | 820 | |
e9ca9eb9 | 821 | struct bus_type i2c_bus_type = { |
f37dd80a DB |
822 | .name = "i2c", |
823 | .match = i2c_device_match, | |
824 | .probe = i2c_device_probe, | |
825 | .remove = i2c_device_remove, | |
826 | .shutdown = i2c_device_shutdown, | |
b864c7d5 | 827 | }; |
e9ca9eb9 | 828 | EXPORT_SYMBOL_GPL(i2c_bus_type); |
b864c7d5 | 829 | |
51298d12 | 830 | static struct device_type i2c_client_type = { |
a5eb71b2 | 831 | .groups = i2c_dev_groups, |
51298d12 JD |
832 | .uevent = i2c_device_uevent, |
833 | .release = i2c_client_dev_release, | |
834 | }; | |
835 | ||
9b766b81 DB |
836 | |
837 | /** | |
838 | * i2c_verify_client - return parameter as i2c_client, or NULL | |
839 | * @dev: device, probably from some driver model iterator | |
840 | * | |
841 | * When traversing the driver model tree, perhaps using driver model | |
842 | * iterators like @device_for_each_child(), you can't assume very much | |
843 | * about the nodes you find. Use this function to avoid oopses caused | |
844 | * by wrongly treating some non-I2C device as an i2c_client. | |
845 | */ | |
846 | struct i2c_client *i2c_verify_client(struct device *dev) | |
847 | { | |
51298d12 | 848 | return (dev->type == &i2c_client_type) |
9b766b81 DB |
849 | ? to_i2c_client(dev) |
850 | : NULL; | |
851 | } | |
852 | EXPORT_SYMBOL(i2c_verify_client); | |
853 | ||
854 | ||
da899f55 WS |
855 | /* Return a unique address which takes the flags of the client into account */ |
856 | static unsigned short i2c_encode_flags_to_addr(struct i2c_client *client) | |
857 | { | |
858 | unsigned short addr = client->addr; | |
859 | ||
860 | /* For some client flags, add an arbitrary offset to avoid collisions */ | |
861 | if (client->flags & I2C_CLIENT_TEN) | |
862 | addr |= I2C_ADDR_OFFSET_TEN_BIT; | |
863 | ||
864 | if (client->flags & I2C_CLIENT_SLAVE) | |
865 | addr |= I2C_ADDR_OFFSET_SLAVE; | |
866 | ||
867 | return addr; | |
868 | } | |
869 | ||
3a89db5f | 870 | /* This is a permissive address validity check, I2C address map constraints |
25985edc | 871 | * are purposely not enforced, except for the general call address. */ |
c4019b70 | 872 | static int i2c_check_addr_validity(unsigned addr, unsigned short flags) |
3a89db5f | 873 | { |
c4019b70 | 874 | if (flags & I2C_CLIENT_TEN) { |
3a89db5f | 875 | /* 10-bit address, all values are valid */ |
c4019b70 | 876 | if (addr > 0x3ff) |
3a89db5f JD |
877 | return -EINVAL; |
878 | } else { | |
879 | /* 7-bit address, reject the general call address */ | |
c4019b70 | 880 | if (addr == 0x00 || addr > 0x7f) |
3a89db5f JD |
881 | return -EINVAL; |
882 | } | |
883 | return 0; | |
884 | } | |
885 | ||
656b8761 JD |
886 | /* And this is a strict address validity check, used when probing. If a |
887 | * device uses a reserved address, then it shouldn't be probed. 7-bit | |
888 | * addressing is assumed, 10-bit address devices are rare and should be | |
889 | * explicitly enumerated. */ | |
66be6056 | 890 | static int i2c_check_7bit_addr_validity_strict(unsigned short addr) |
656b8761 JD |
891 | { |
892 | /* | |
893 | * Reserved addresses per I2C specification: | |
894 | * 0x00 General call address / START byte | |
895 | * 0x01 CBUS address | |
896 | * 0x02 Reserved for different bus format | |
897 | * 0x03 Reserved for future purposes | |
898 | * 0x04-0x07 Hs-mode master code | |
899 | * 0x78-0x7b 10-bit slave addressing | |
900 | * 0x7c-0x7f Reserved for future purposes | |
901 | */ | |
902 | if (addr < 0x08 || addr > 0x77) | |
903 | return -EINVAL; | |
904 | return 0; | |
905 | } | |
906 | ||
3b5f794b JD |
907 | static int __i2c_check_addr_busy(struct device *dev, void *addrp) |
908 | { | |
909 | struct i2c_client *client = i2c_verify_client(dev); | |
910 | int addr = *(int *)addrp; | |
911 | ||
9bccc70a | 912 | if (client && i2c_encode_flags_to_addr(client) == addr) |
3b5f794b JD |
913 | return -EBUSY; |
914 | return 0; | |
915 | } | |
916 | ||
0826374b ML |
917 | /* walk up mux tree */ |
918 | static int i2c_check_mux_parents(struct i2c_adapter *adapter, int addr) | |
919 | { | |
97cc4d49 | 920 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
0826374b ML |
921 | int result; |
922 | ||
923 | result = device_for_each_child(&adapter->dev, &addr, | |
924 | __i2c_check_addr_busy); | |
925 | ||
97cc4d49 JD |
926 | if (!result && parent) |
927 | result = i2c_check_mux_parents(parent, addr); | |
0826374b ML |
928 | |
929 | return result; | |
930 | } | |
931 | ||
932 | /* recurse down mux tree */ | |
933 | static int i2c_check_mux_children(struct device *dev, void *addrp) | |
934 | { | |
935 | int result; | |
936 | ||
937 | if (dev->type == &i2c_adapter_type) | |
938 | result = device_for_each_child(dev, addrp, | |
939 | i2c_check_mux_children); | |
940 | else | |
941 | result = __i2c_check_addr_busy(dev, addrp); | |
942 | ||
943 | return result; | |
944 | } | |
945 | ||
3b5f794b JD |
946 | static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr) |
947 | { | |
97cc4d49 | 948 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
0826374b ML |
949 | int result = 0; |
950 | ||
97cc4d49 JD |
951 | if (parent) |
952 | result = i2c_check_mux_parents(parent, addr); | |
0826374b ML |
953 | |
954 | if (!result) | |
955 | result = device_for_each_child(&adapter->dev, &addr, | |
956 | i2c_check_mux_children); | |
957 | ||
958 | return result; | |
3b5f794b JD |
959 | } |
960 | ||
fe61e07e JD |
961 | /** |
962 | * i2c_lock_adapter - Get exclusive access to an I2C bus segment | |
963 | * @adapter: Target I2C bus segment | |
964 | */ | |
965 | void i2c_lock_adapter(struct i2c_adapter *adapter) | |
966 | { | |
97cc4d49 JD |
967 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
968 | ||
969 | if (parent) | |
970 | i2c_lock_adapter(parent); | |
0826374b ML |
971 | else |
972 | rt_mutex_lock(&adapter->bus_lock); | |
fe61e07e JD |
973 | } |
974 | EXPORT_SYMBOL_GPL(i2c_lock_adapter); | |
975 | ||
976 | /** | |
977 | * i2c_trylock_adapter - Try to get exclusive access to an I2C bus segment | |
978 | * @adapter: Target I2C bus segment | |
979 | */ | |
980 | static int i2c_trylock_adapter(struct i2c_adapter *adapter) | |
981 | { | |
97cc4d49 JD |
982 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
983 | ||
984 | if (parent) | |
985 | return i2c_trylock_adapter(parent); | |
0826374b ML |
986 | else |
987 | return rt_mutex_trylock(&adapter->bus_lock); | |
fe61e07e JD |
988 | } |
989 | ||
990 | /** | |
991 | * i2c_unlock_adapter - Release exclusive access to an I2C bus segment | |
992 | * @adapter: Target I2C bus segment | |
993 | */ | |
994 | void i2c_unlock_adapter(struct i2c_adapter *adapter) | |
995 | { | |
97cc4d49 JD |
996 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
997 | ||
998 | if (parent) | |
999 | i2c_unlock_adapter(parent); | |
0826374b ML |
1000 | else |
1001 | rt_mutex_unlock(&adapter->bus_lock); | |
fe61e07e JD |
1002 | } |
1003 | EXPORT_SYMBOL_GPL(i2c_unlock_adapter); | |
1004 | ||
70762abb JN |
1005 | static void i2c_dev_set_name(struct i2c_adapter *adap, |
1006 | struct i2c_client *client) | |
1007 | { | |
1008 | struct acpi_device *adev = ACPI_COMPANION(&client->dev); | |
1009 | ||
1010 | if (adev) { | |
1011 | dev_set_name(&client->dev, "i2c-%s", acpi_dev_name(adev)); | |
1012 | return; | |
1013 | } | |
1014 | ||
70762abb | 1015 | dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap), |
da899f55 | 1016 | i2c_encode_flags_to_addr(client)); |
70762abb JN |
1017 | } |
1018 | ||
9c1600ed | 1019 | /** |
f8a227e8 | 1020 | * i2c_new_device - instantiate an i2c device |
9c1600ed DB |
1021 | * @adap: the adapter managing the device |
1022 | * @info: describes one I2C device; bus_num is ignored | |
d64f73be | 1023 | * Context: can sleep |
9c1600ed | 1024 | * |
f8a227e8 JD |
1025 | * Create an i2c device. Binding is handled through driver model |
1026 | * probe()/remove() methods. A driver may be bound to this device when we | |
1027 | * return from this function, or any later moment (e.g. maybe hotplugging will | |
1028 | * load the driver module). This call is not appropriate for use by mainboard | |
1029 | * initialization logic, which usually runs during an arch_initcall() long | |
1030 | * before any i2c_adapter could exist. | |
9c1600ed DB |
1031 | * |
1032 | * This returns the new i2c client, which may be saved for later use with | |
1033 | * i2c_unregister_device(); or NULL to indicate an error. | |
1034 | */ | |
1035 | struct i2c_client * | |
1036 | i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) | |
1037 | { | |
1038 | struct i2c_client *client; | |
1039 | int status; | |
1040 | ||
1041 | client = kzalloc(sizeof *client, GFP_KERNEL); | |
1042 | if (!client) | |
1043 | return NULL; | |
1044 | ||
1045 | client->adapter = adap; | |
1046 | ||
1047 | client->dev.platform_data = info->platform_data; | |
3bbb835d | 1048 | |
11f1f2af AV |
1049 | if (info->archdata) |
1050 | client->dev.archdata = *info->archdata; | |
1051 | ||
ee35425c | 1052 | client->flags = info->flags; |
9c1600ed DB |
1053 | client->addr = info->addr; |
1054 | client->irq = info->irq; | |
1055 | ||
9c1600ed DB |
1056 | strlcpy(client->name, info->type, sizeof(client->name)); |
1057 | ||
c4019b70 | 1058 | status = i2c_check_addr_validity(client->addr, client->flags); |
3a89db5f JD |
1059 | if (status) { |
1060 | dev_err(&adap->dev, "Invalid %d-bit I2C address 0x%02hx\n", | |
1061 | client->flags & I2C_CLIENT_TEN ? 10 : 7, client->addr); | |
1062 | goto out_err_silent; | |
1063 | } | |
1064 | ||
f8a227e8 | 1065 | /* Check for address business */ |
9bccc70a | 1066 | status = i2c_check_addr_busy(adap, i2c_encode_flags_to_addr(client)); |
f8a227e8 JD |
1067 | if (status) |
1068 | goto out_err; | |
1069 | ||
1070 | client->dev.parent = &client->adapter->dev; | |
1071 | client->dev.bus = &i2c_bus_type; | |
51298d12 | 1072 | client->dev.type = &i2c_client_type; |
d12d42f7 | 1073 | client->dev.of_node = info->of_node; |
ce793486 | 1074 | client->dev.fwnode = info->fwnode; |
f8a227e8 | 1075 | |
70762abb | 1076 | i2c_dev_set_name(adap, client); |
f8a227e8 JD |
1077 | status = device_register(&client->dev); |
1078 | if (status) | |
1079 | goto out_err; | |
1080 | ||
f8a227e8 JD |
1081 | dev_dbg(&adap->dev, "client [%s] registered with bus id %s\n", |
1082 | client->name, dev_name(&client->dev)); | |
1083 | ||
9c1600ed | 1084 | return client; |
f8a227e8 JD |
1085 | |
1086 | out_err: | |
1087 | dev_err(&adap->dev, "Failed to register i2c client %s at 0x%02x " | |
1088 | "(%d)\n", client->name, client->addr, status); | |
3a89db5f | 1089 | out_err_silent: |
f8a227e8 JD |
1090 | kfree(client); |
1091 | return NULL; | |
9c1600ed DB |
1092 | } |
1093 | EXPORT_SYMBOL_GPL(i2c_new_device); | |
1094 | ||
1095 | ||
1096 | /** | |
1097 | * i2c_unregister_device - reverse effect of i2c_new_device() | |
1098 | * @client: value returned from i2c_new_device() | |
d64f73be | 1099 | * Context: can sleep |
9c1600ed DB |
1100 | */ |
1101 | void i2c_unregister_device(struct i2c_client *client) | |
a1d9e6e4 | 1102 | { |
4f001fd3 PA |
1103 | if (client->dev.of_node) |
1104 | of_node_clear_flag(client->dev.of_node, OF_POPULATED); | |
a1d9e6e4 DB |
1105 | device_unregister(&client->dev); |
1106 | } | |
9c1600ed | 1107 | EXPORT_SYMBOL_GPL(i2c_unregister_device); |
a1d9e6e4 DB |
1108 | |
1109 | ||
60b129d7 JD |
1110 | static const struct i2c_device_id dummy_id[] = { |
1111 | { "dummy", 0 }, | |
1112 | { }, | |
1113 | }; | |
1114 | ||
d2653e92 JD |
1115 | static int dummy_probe(struct i2c_client *client, |
1116 | const struct i2c_device_id *id) | |
1117 | { | |
1118 | return 0; | |
1119 | } | |
1120 | ||
1121 | static int dummy_remove(struct i2c_client *client) | |
e9f1373b DB |
1122 | { |
1123 | return 0; | |
1124 | } | |
1125 | ||
1126 | static struct i2c_driver dummy_driver = { | |
1127 | .driver.name = "dummy", | |
d2653e92 JD |
1128 | .probe = dummy_probe, |
1129 | .remove = dummy_remove, | |
60b129d7 | 1130 | .id_table = dummy_id, |
e9f1373b DB |
1131 | }; |
1132 | ||
1133 | /** | |
1134 | * i2c_new_dummy - return a new i2c device bound to a dummy driver | |
1135 | * @adapter: the adapter managing the device | |
1136 | * @address: seven bit address to be used | |
e9f1373b DB |
1137 | * Context: can sleep |
1138 | * | |
1139 | * This returns an I2C client bound to the "dummy" driver, intended for use | |
1140 | * with devices that consume multiple addresses. Examples of such chips | |
1141 | * include various EEPROMS (like 24c04 and 24c08 models). | |
1142 | * | |
1143 | * These dummy devices have two main uses. First, most I2C and SMBus calls | |
1144 | * except i2c_transfer() need a client handle; the dummy will be that handle. | |
1145 | * And second, this prevents the specified address from being bound to a | |
1146 | * different driver. | |
1147 | * | |
1148 | * This returns the new i2c client, which should be saved for later use with | |
1149 | * i2c_unregister_device(); or NULL to indicate an error. | |
1150 | */ | |
09b8ce0a | 1151 | struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) |
e9f1373b DB |
1152 | { |
1153 | struct i2c_board_info info = { | |
60b129d7 | 1154 | I2C_BOARD_INFO("dummy", address), |
e9f1373b DB |
1155 | }; |
1156 | ||
e9f1373b DB |
1157 | return i2c_new_device(adapter, &info); |
1158 | } | |
1159 | EXPORT_SYMBOL_GPL(i2c_new_dummy); | |
1160 | ||
f37dd80a DB |
1161 | /* ------------------------------------------------------------------------- */ |
1162 | ||
16ffadfc DB |
1163 | /* I2C bus adapters -- one roots each I2C or SMBUS segment */ |
1164 | ||
83eaaed0 | 1165 | static void i2c_adapter_dev_release(struct device *dev) |
1da177e4 | 1166 | { |
ef2c8321 | 1167 | struct i2c_adapter *adap = to_i2c_adapter(dev); |
1da177e4 LT |
1168 | complete(&adap->dev_released); |
1169 | } | |
1170 | ||
390946b1 JD |
1171 | /* |
1172 | * This function is only needed for mutex_lock_nested, so it is never | |
1173 | * called unless locking correctness checking is enabled. Thus we | |
1174 | * make it inline to avoid a compiler warning. That's what gcc ends up | |
1175 | * doing anyway. | |
1176 | */ | |
1177 | static inline unsigned int i2c_adapter_depth(struct i2c_adapter *adapter) | |
1178 | { | |
1179 | unsigned int depth = 0; | |
1180 | ||
1181 | while ((adapter = i2c_parent_is_i2c_adapter(adapter))) | |
1182 | depth++; | |
1183 | ||
1184 | return depth; | |
1185 | } | |
1186 | ||
99cd8e25 JD |
1187 | /* |
1188 | * Let users instantiate I2C devices through sysfs. This can be used when | |
1189 | * platform initialization code doesn't contain the proper data for | |
1190 | * whatever reason. Also useful for drivers that do device detection and | |
1191 | * detection fails, either because the device uses an unexpected address, | |
1192 | * or this is a compatible device with different ID register values. | |
1193 | * | |
1194 | * Parameter checking may look overzealous, but we really don't want | |
1195 | * the user to provide incorrect parameters. | |
1196 | */ | |
1197 | static ssize_t | |
1198 | i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr, | |
1199 | const char *buf, size_t count) | |
1200 | { | |
1201 | struct i2c_adapter *adap = to_i2c_adapter(dev); | |
1202 | struct i2c_board_info info; | |
1203 | struct i2c_client *client; | |
1204 | char *blank, end; | |
1205 | int res; | |
1206 | ||
99cd8e25 JD |
1207 | memset(&info, 0, sizeof(struct i2c_board_info)); |
1208 | ||
1209 | blank = strchr(buf, ' '); | |
1210 | if (!blank) { | |
1211 | dev_err(dev, "%s: Missing parameters\n", "new_device"); | |
1212 | return -EINVAL; | |
1213 | } | |
1214 | if (blank - buf > I2C_NAME_SIZE - 1) { | |
1215 | dev_err(dev, "%s: Invalid device name\n", "new_device"); | |
1216 | return -EINVAL; | |
1217 | } | |
1218 | memcpy(info.type, buf, blank - buf); | |
1219 | ||
1220 | /* Parse remaining parameters, reject extra parameters */ | |
1221 | res = sscanf(++blank, "%hi%c", &info.addr, &end); | |
1222 | if (res < 1) { | |
1223 | dev_err(dev, "%s: Can't parse I2C address\n", "new_device"); | |
1224 | return -EINVAL; | |
1225 | } | |
1226 | if (res > 1 && end != '\n') { | |
1227 | dev_err(dev, "%s: Extra parameters\n", "new_device"); | |
1228 | return -EINVAL; | |
1229 | } | |
1230 | ||
cfa0327b WS |
1231 | if ((info.addr & I2C_ADDR_OFFSET_TEN_BIT) == I2C_ADDR_OFFSET_TEN_BIT) { |
1232 | info.addr &= ~I2C_ADDR_OFFSET_TEN_BIT; | |
1233 | info.flags |= I2C_CLIENT_TEN; | |
1234 | } | |
1235 | ||
1236 | if (info.addr & I2C_ADDR_OFFSET_SLAVE) { | |
1237 | info.addr &= ~I2C_ADDR_OFFSET_SLAVE; | |
1238 | info.flags |= I2C_CLIENT_SLAVE; | |
1239 | } | |
1240 | ||
99cd8e25 JD |
1241 | client = i2c_new_device(adap, &info); |
1242 | if (!client) | |
3a89db5f | 1243 | return -EINVAL; |
99cd8e25 JD |
1244 | |
1245 | /* Keep track of the added device */ | |
dafc50d1 | 1246 | mutex_lock(&adap->userspace_clients_lock); |
6629dcff | 1247 | list_add_tail(&client->detected, &adap->userspace_clients); |
dafc50d1 | 1248 | mutex_unlock(&adap->userspace_clients_lock); |
99cd8e25 JD |
1249 | dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device", |
1250 | info.type, info.addr); | |
1251 | ||
1252 | return count; | |
1253 | } | |
a5eb71b2 | 1254 | static DEVICE_ATTR(new_device, S_IWUSR, NULL, i2c_sysfs_new_device); |
99cd8e25 JD |
1255 | |
1256 | /* | |
1257 | * And of course let the users delete the devices they instantiated, if | |
1258 | * they got it wrong. This interface can only be used to delete devices | |
1259 | * instantiated by i2c_sysfs_new_device above. This guarantees that we | |
1260 | * don't delete devices to which some kernel code still has references. | |
1261 | * | |
1262 | * Parameter checking may look overzealous, but we really don't want | |
1263 | * the user to delete the wrong device. | |
1264 | */ | |
1265 | static ssize_t | |
1266 | i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr, | |
1267 | const char *buf, size_t count) | |
1268 | { | |
1269 | struct i2c_adapter *adap = to_i2c_adapter(dev); | |
1270 | struct i2c_client *client, *next; | |
1271 | unsigned short addr; | |
1272 | char end; | |
1273 | int res; | |
1274 | ||
1275 | /* Parse parameters, reject extra parameters */ | |
1276 | res = sscanf(buf, "%hi%c", &addr, &end); | |
1277 | if (res < 1) { | |
1278 | dev_err(dev, "%s: Can't parse I2C address\n", "delete_device"); | |
1279 | return -EINVAL; | |
1280 | } | |
1281 | if (res > 1 && end != '\n') { | |
1282 | dev_err(dev, "%s: Extra parameters\n", "delete_device"); | |
1283 | return -EINVAL; | |
1284 | } | |
1285 | ||
1286 | /* Make sure the device was added through sysfs */ | |
1287 | res = -ENOENT; | |
390946b1 JD |
1288 | mutex_lock_nested(&adap->userspace_clients_lock, |
1289 | i2c_adapter_depth(adap)); | |
6629dcff JD |
1290 | list_for_each_entry_safe(client, next, &adap->userspace_clients, |
1291 | detected) { | |
cfa0327b | 1292 | if (i2c_encode_flags_to_addr(client) == addr) { |
99cd8e25 JD |
1293 | dev_info(dev, "%s: Deleting device %s at 0x%02hx\n", |
1294 | "delete_device", client->name, client->addr); | |
1295 | ||
1296 | list_del(&client->detected); | |
1297 | i2c_unregister_device(client); | |
1298 | res = count; | |
1299 | break; | |
1300 | } | |
1301 | } | |
dafc50d1 | 1302 | mutex_unlock(&adap->userspace_clients_lock); |
99cd8e25 JD |
1303 | |
1304 | if (res < 0) | |
1305 | dev_err(dev, "%s: Can't find device in list\n", | |
1306 | "delete_device"); | |
1307 | return res; | |
1308 | } | |
e9b526fe AS |
1309 | static DEVICE_ATTR_IGNORE_LOCKDEP(delete_device, S_IWUSR, NULL, |
1310 | i2c_sysfs_delete_device); | |
4f8cf824 JD |
1311 | |
1312 | static struct attribute *i2c_adapter_attrs[] = { | |
1313 | &dev_attr_name.attr, | |
1314 | &dev_attr_new_device.attr, | |
1315 | &dev_attr_delete_device.attr, | |
1316 | NULL | |
1317 | }; | |
a5eb71b2 | 1318 | ATTRIBUTE_GROUPS(i2c_adapter); |
b119dc3f | 1319 | |
0826374b | 1320 | struct device_type i2c_adapter_type = { |
a5eb71b2 | 1321 | .groups = i2c_adapter_groups, |
4f8cf824 | 1322 | .release = i2c_adapter_dev_release, |
1da177e4 | 1323 | }; |
0826374b | 1324 | EXPORT_SYMBOL_GPL(i2c_adapter_type); |
1da177e4 | 1325 | |
643dd09e SW |
1326 | /** |
1327 | * i2c_verify_adapter - return parameter as i2c_adapter or NULL | |
1328 | * @dev: device, probably from some driver model iterator | |
1329 | * | |
1330 | * When traversing the driver model tree, perhaps using driver model | |
1331 | * iterators like @device_for_each_child(), you can't assume very much | |
1332 | * about the nodes you find. Use this function to avoid oopses caused | |
1333 | * by wrongly treating some non-I2C device as an i2c_adapter. | |
1334 | */ | |
1335 | struct i2c_adapter *i2c_verify_adapter(struct device *dev) | |
1336 | { | |
1337 | return (dev->type == &i2c_adapter_type) | |
1338 | ? to_i2c_adapter(dev) | |
1339 | : NULL; | |
1340 | } | |
1341 | EXPORT_SYMBOL(i2c_verify_adapter); | |
1342 | ||
2bb5095a JD |
1343 | #ifdef CONFIG_I2C_COMPAT |
1344 | static struct class_compat *i2c_adapter_compat_class; | |
1345 | #endif | |
1346 | ||
9c1600ed DB |
1347 | static void i2c_scan_static_board_info(struct i2c_adapter *adapter) |
1348 | { | |
1349 | struct i2c_devinfo *devinfo; | |
1350 | ||
f18c41da | 1351 | down_read(&__i2c_board_lock); |
9c1600ed DB |
1352 | list_for_each_entry(devinfo, &__i2c_board_list, list) { |
1353 | if (devinfo->busnum == adapter->nr | |
1354 | && !i2c_new_device(adapter, | |
1355 | &devinfo->board_info)) | |
09b8ce0a ZX |
1356 | dev_err(&adapter->dev, |
1357 | "Can't create device at 0x%02x\n", | |
9c1600ed DB |
1358 | devinfo->board_info.addr); |
1359 | } | |
f18c41da | 1360 | up_read(&__i2c_board_lock); |
9c1600ed DB |
1361 | } |
1362 | ||
687b81d0 WS |
1363 | /* OF support code */ |
1364 | ||
1365 | #if IS_ENABLED(CONFIG_OF) | |
a430a345 PA |
1366 | static struct i2c_client *of_i2c_register_device(struct i2c_adapter *adap, |
1367 | struct device_node *node) | |
687b81d0 | 1368 | { |
a430a345 PA |
1369 | struct i2c_client *result; |
1370 | struct i2c_board_info info = {}; | |
1371 | struct dev_archdata dev_ad = {}; | |
b4e2f6ac WS |
1372 | const __be32 *addr_be; |
1373 | u32 addr; | |
a430a345 | 1374 | int len; |
687b81d0 | 1375 | |
a430a345 | 1376 | dev_dbg(&adap->dev, "of_i2c: register %s\n", node->full_name); |
687b81d0 | 1377 | |
a430a345 PA |
1378 | if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) { |
1379 | dev_err(&adap->dev, "of_i2c: modalias failure on %s\n", | |
1380 | node->full_name); | |
1381 | return ERR_PTR(-EINVAL); | |
1382 | } | |
687b81d0 | 1383 | |
b4e2f6ac WS |
1384 | addr_be = of_get_property(node, "reg", &len); |
1385 | if (!addr_be || (len < sizeof(*addr_be))) { | |
a430a345 PA |
1386 | dev_err(&adap->dev, "of_i2c: invalid reg on %s\n", |
1387 | node->full_name); | |
1388 | return ERR_PTR(-EINVAL); | |
1389 | } | |
687b81d0 | 1390 | |
b4e2f6ac WS |
1391 | addr = be32_to_cpup(addr_be); |
1392 | if (addr & I2C_TEN_BIT_ADDRESS) { | |
1393 | addr &= ~I2C_TEN_BIT_ADDRESS; | |
1394 | info.flags |= I2C_CLIENT_TEN; | |
1395 | } | |
1396 | ||
1397 | if (addr & I2C_OWN_SLAVE_ADDRESS) { | |
1398 | addr &= ~I2C_OWN_SLAVE_ADDRESS; | |
1399 | info.flags |= I2C_CLIENT_SLAVE; | |
1400 | } | |
1401 | ||
1402 | if (i2c_check_addr_validity(addr, info.flags)) { | |
a430a345 PA |
1403 | dev_err(&adap->dev, "of_i2c: invalid addr=%x on %s\n", |
1404 | info.addr, node->full_name); | |
1405 | return ERR_PTR(-EINVAL); | |
1406 | } | |
687b81d0 | 1407 | |
b4e2f6ac | 1408 | info.addr = addr; |
a430a345 PA |
1409 | info.of_node = of_node_get(node); |
1410 | info.archdata = &dev_ad; | |
687b81d0 | 1411 | |
a430a345 PA |
1412 | if (of_get_property(node, "wakeup-source", NULL)) |
1413 | info.flags |= I2C_CLIENT_WAKE; | |
687b81d0 | 1414 | |
a430a345 PA |
1415 | result = i2c_new_device(adap, &info); |
1416 | if (result == NULL) { | |
1417 | dev_err(&adap->dev, "of_i2c: Failure registering %s\n", | |
1418 | node->full_name); | |
1419 | of_node_put(node); | |
a430a345 PA |
1420 | return ERR_PTR(-EINVAL); |
1421 | } | |
1422 | return result; | |
1423 | } | |
687b81d0 | 1424 | |
a430a345 PA |
1425 | static void of_i2c_register_devices(struct i2c_adapter *adap) |
1426 | { | |
1427 | struct device_node *node; | |
687b81d0 | 1428 | |
a430a345 PA |
1429 | /* Only register child devices if the adapter has a node pointer set */ |
1430 | if (!adap->dev.of_node) | |
1431 | return; | |
687b81d0 | 1432 | |
a430a345 PA |
1433 | dev_dbg(&adap->dev, "of_i2c: walking child nodes\n"); |
1434 | ||
4f001fd3 PA |
1435 | for_each_available_child_of_node(adap->dev.of_node, node) { |
1436 | if (of_node_test_and_set_flag(node, OF_POPULATED)) | |
1437 | continue; | |
a430a345 | 1438 | of_i2c_register_device(adap, node); |
4f001fd3 | 1439 | } |
687b81d0 WS |
1440 | } |
1441 | ||
1442 | static int of_dev_node_match(struct device *dev, void *data) | |
1443 | { | |
1444 | return dev->of_node == data; | |
1445 | } | |
1446 | ||
1447 | /* must call put_device() when done with returned i2c_client device */ | |
1448 | struct i2c_client *of_find_i2c_device_by_node(struct device_node *node) | |
1449 | { | |
1450 | struct device *dev; | |
e3311469 | 1451 | struct i2c_client *client; |
687b81d0 | 1452 | |
e3311469 | 1453 | dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match); |
687b81d0 WS |
1454 | if (!dev) |
1455 | return NULL; | |
1456 | ||
e3311469 VZ |
1457 | client = i2c_verify_client(dev); |
1458 | if (!client) | |
1459 | put_device(dev); | |
1460 | ||
1461 | return client; | |
687b81d0 WS |
1462 | } |
1463 | EXPORT_SYMBOL(of_find_i2c_device_by_node); | |
1464 | ||
1465 | /* must call put_device() when done with returned i2c_adapter device */ | |
1466 | struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node) | |
1467 | { | |
1468 | struct device *dev; | |
e3311469 | 1469 | struct i2c_adapter *adapter; |
687b81d0 | 1470 | |
e3311469 | 1471 | dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match); |
687b81d0 WS |
1472 | if (!dev) |
1473 | return NULL; | |
1474 | ||
e3311469 VZ |
1475 | adapter = i2c_verify_adapter(dev); |
1476 | if (!adapter) | |
1477 | put_device(dev); | |
1478 | ||
1479 | return adapter; | |
687b81d0 WS |
1480 | } |
1481 | EXPORT_SYMBOL(of_find_i2c_adapter_by_node); | |
48e9743d VZ |
1482 | |
1483 | /* must call i2c_put_adapter() when done with returned i2c_adapter device */ | |
1484 | struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node) | |
1485 | { | |
1486 | struct i2c_adapter *adapter; | |
1487 | ||
1488 | adapter = of_find_i2c_adapter_by_node(node); | |
1489 | if (!adapter) | |
1490 | return NULL; | |
1491 | ||
1492 | if (!try_module_get(adapter->owner)) { | |
1493 | put_device(&adapter->dev); | |
1494 | adapter = NULL; | |
1495 | } | |
1496 | ||
1497 | return adapter; | |
1498 | } | |
1499 | EXPORT_SYMBOL(of_get_i2c_adapter_by_node); | |
687b81d0 WS |
1500 | #else |
1501 | static void of_i2c_register_devices(struct i2c_adapter *adap) { } | |
1502 | #endif /* CONFIG_OF */ | |
1503 | ||
69b0089a JD |
1504 | static int i2c_do_add_adapter(struct i2c_driver *driver, |
1505 | struct i2c_adapter *adap) | |
026526f5 | 1506 | { |
4735c98f JD |
1507 | /* Detect supported devices on that bus, and instantiate them */ |
1508 | i2c_detect(adap, driver); | |
1509 | ||
1510 | /* Let legacy drivers scan this bus for matching devices */ | |
026526f5 | 1511 | if (driver->attach_adapter) { |
a920ff41 JD |
1512 | dev_warn(&adap->dev, "%s: attach_adapter method is deprecated\n", |
1513 | driver->driver.name); | |
fe6fc258 JD |
1514 | dev_warn(&adap->dev, "Please use another way to instantiate " |
1515 | "your i2c_client\n"); | |
026526f5 JD |
1516 | /* We ignore the return code; if it fails, too bad */ |
1517 | driver->attach_adapter(adap); | |
1518 | } | |
1519 | return 0; | |
1520 | } | |
1521 | ||
69b0089a JD |
1522 | static int __process_new_adapter(struct device_driver *d, void *data) |
1523 | { | |
1524 | return i2c_do_add_adapter(to_i2c_driver(d), data); | |
1525 | } | |
1526 | ||
6e13e641 | 1527 | static int i2c_register_adapter(struct i2c_adapter *adap) |
1da177e4 | 1528 | { |
d6703281 | 1529 | int res = 0; |
1da177e4 | 1530 | |
1d0b19c9 | 1531 | /* Can't register until after driver model init */ |
35fc37f8 JD |
1532 | if (unlikely(WARN_ON(!i2c_bus_type.p))) { |
1533 | res = -EAGAIN; | |
1534 | goto out_list; | |
1535 | } | |
1d0b19c9 | 1536 | |
2236baa7 JD |
1537 | /* Sanity checks */ |
1538 | if (unlikely(adap->name[0] == '\0')) { | |
1539 | pr_err("i2c-core: Attempt to register an adapter with " | |
1540 | "no name!\n"); | |
1541 | return -EINVAL; | |
1542 | } | |
1543 | if (unlikely(!adap->algo)) { | |
1544 | pr_err("i2c-core: Attempt to register adapter '%s' with " | |
1545 | "no algo!\n", adap->name); | |
1546 | return -EINVAL; | |
1547 | } | |
1548 | ||
194684e5 | 1549 | rt_mutex_init(&adap->bus_lock); |
dafc50d1 | 1550 | mutex_init(&adap->userspace_clients_lock); |
6629dcff | 1551 | INIT_LIST_HEAD(&adap->userspace_clients); |
1da177e4 | 1552 | |
8fcfef6e JD |
1553 | /* Set default timeout to 1 second if not already set */ |
1554 | if (adap->timeout == 0) | |
1555 | adap->timeout = HZ; | |
1556 | ||
27d9c183 | 1557 | dev_set_name(&adap->dev, "i2c-%d", adap->nr); |
4f8cf824 JD |
1558 | adap->dev.bus = &i2c_bus_type; |
1559 | adap->dev.type = &i2c_adapter_type; | |
b119c6c9 JD |
1560 | res = device_register(&adap->dev); |
1561 | if (res) | |
1562 | goto out_list; | |
1da177e4 | 1563 | |
b6d7b3d1 JD |
1564 | dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name); |
1565 | ||
6ada5c1e | 1566 | pm_runtime_no_callbacks(&adap->dev); |
9f924169 | 1567 | pm_runtime_enable(&adap->dev); |
6ada5c1e | 1568 | |
2bb5095a JD |
1569 | #ifdef CONFIG_I2C_COMPAT |
1570 | res = class_compat_create_link(i2c_adapter_compat_class, &adap->dev, | |
1571 | adap->dev.parent); | |
1572 | if (res) | |
1573 | dev_warn(&adap->dev, | |
1574 | "Failed to create compatibility class link\n"); | |
1575 | #endif | |
1576 | ||
5f9296ba VK |
1577 | /* bus recovery specific initialization */ |
1578 | if (adap->bus_recovery_info) { | |
1579 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
1580 | ||
1581 | if (!bri->recover_bus) { | |
1582 | dev_err(&adap->dev, "No recover_bus() found, not using recovery\n"); | |
1583 | adap->bus_recovery_info = NULL; | |
1584 | goto exit_recovery; | |
1585 | } | |
1586 | ||
1587 | /* Generic GPIO recovery */ | |
1588 | if (bri->recover_bus == i2c_generic_gpio_recovery) { | |
1589 | if (!gpio_is_valid(bri->scl_gpio)) { | |
1590 | dev_err(&adap->dev, "Invalid SCL gpio, not using recovery\n"); | |
1591 | adap->bus_recovery_info = NULL; | |
1592 | goto exit_recovery; | |
1593 | } | |
1594 | ||
1595 | if (gpio_is_valid(bri->sda_gpio)) | |
1596 | bri->get_sda = get_sda_gpio_value; | |
1597 | else | |
1598 | bri->get_sda = NULL; | |
1599 | ||
1600 | bri->get_scl = get_scl_gpio_value; | |
1601 | bri->set_scl = set_scl_gpio_value; | |
1602 | } else if (!bri->set_scl || !bri->get_scl) { | |
1603 | /* Generic SCL recovery */ | |
1604 | dev_err(&adap->dev, "No {get|set}_gpio() found, not using recovery\n"); | |
1605 | adap->bus_recovery_info = NULL; | |
1606 | } | |
1607 | } | |
1608 | ||
1609 | exit_recovery: | |
729d6dd5 | 1610 | /* create pre-declared device nodes */ |
687b81d0 | 1611 | of_i2c_register_devices(adap); |
55e71edb | 1612 | acpi_i2c_register_devices(adap); |
5d98e61d | 1613 | acpi_i2c_install_space_handler(adap); |
687b81d0 | 1614 | |
6e13e641 DB |
1615 | if (adap->nr < __i2c_first_dynamic_bus_num) |
1616 | i2c_scan_static_board_info(adap); | |
1617 | ||
4735c98f | 1618 | /* Notify drivers */ |
35fc37f8 | 1619 | mutex_lock(&core_lock); |
d6703281 | 1620 | bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter); |
caada32a | 1621 | mutex_unlock(&core_lock); |
35fc37f8 JD |
1622 | |
1623 | return 0; | |
b119c6c9 | 1624 | |
b119c6c9 | 1625 | out_list: |
35fc37f8 | 1626 | mutex_lock(&core_lock); |
b119c6c9 | 1627 | idr_remove(&i2c_adapter_idr, adap->nr); |
35fc37f8 JD |
1628 | mutex_unlock(&core_lock); |
1629 | return res; | |
1da177e4 LT |
1630 | } |
1631 | ||
ee5c2744 DA |
1632 | /** |
1633 | * __i2c_add_numbered_adapter - i2c_add_numbered_adapter where nr is never -1 | |
1634 | * @adap: the adapter to register (with adap->nr initialized) | |
1635 | * Context: can sleep | |
1636 | * | |
1637 | * See i2c_add_numbered_adapter() for details. | |
1638 | */ | |
1639 | static int __i2c_add_numbered_adapter(struct i2c_adapter *adap) | |
1640 | { | |
1641 | int id; | |
1642 | ||
1643 | mutex_lock(&core_lock); | |
1644 | id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1, | |
1645 | GFP_KERNEL); | |
1646 | mutex_unlock(&core_lock); | |
1647 | if (id < 0) | |
1648 | return id == -ENOSPC ? -EBUSY : id; | |
1649 | ||
1650 | return i2c_register_adapter(adap); | |
1651 | } | |
1652 | ||
6e13e641 DB |
1653 | /** |
1654 | * i2c_add_adapter - declare i2c adapter, use dynamic bus number | |
1655 | * @adapter: the adapter to add | |
d64f73be | 1656 | * Context: can sleep |
6e13e641 DB |
1657 | * |
1658 | * This routine is used to declare an I2C adapter when its bus number | |
ee5c2744 DA |
1659 | * doesn't matter or when its bus number is specified by an dt alias. |
1660 | * Examples of bases when the bus number doesn't matter: I2C adapters | |
1661 | * dynamically added by USB links or PCI plugin cards. | |
6e13e641 DB |
1662 | * |
1663 | * When this returns zero, a new bus number was allocated and stored | |
1664 | * in adap->nr, and the specified adapter became available for clients. | |
1665 | * Otherwise, a negative errno value is returned. | |
1666 | */ | |
1667 | int i2c_add_adapter(struct i2c_adapter *adapter) | |
1668 | { | |
ee5c2744 | 1669 | struct device *dev = &adapter->dev; |
4ae42b0f | 1670 | int id; |
6e13e641 | 1671 | |
ee5c2744 DA |
1672 | if (dev->of_node) { |
1673 | id = of_alias_get_id(dev->of_node, "i2c"); | |
1674 | if (id >= 0) { | |
1675 | adapter->nr = id; | |
1676 | return __i2c_add_numbered_adapter(adapter); | |
1677 | } | |
1678 | } | |
1679 | ||
caada32a | 1680 | mutex_lock(&core_lock); |
4ae42b0f TH |
1681 | id = idr_alloc(&i2c_adapter_idr, adapter, |
1682 | __i2c_first_dynamic_bus_num, 0, GFP_KERNEL); | |
caada32a | 1683 | mutex_unlock(&core_lock); |
4ae42b0f TH |
1684 | if (id < 0) |
1685 | return id; | |
6e13e641 DB |
1686 | |
1687 | adapter->nr = id; | |
4ae42b0f | 1688 | |
6e13e641 DB |
1689 | return i2c_register_adapter(adapter); |
1690 | } | |
1691 | EXPORT_SYMBOL(i2c_add_adapter); | |
1692 | ||
1693 | /** | |
1694 | * i2c_add_numbered_adapter - declare i2c adapter, use static bus number | |
1695 | * @adap: the adapter to register (with adap->nr initialized) | |
d64f73be | 1696 | * Context: can sleep |
6e13e641 DB |
1697 | * |
1698 | * This routine is used to declare an I2C adapter when its bus number | |
8c07e46f RD |
1699 | * matters. For example, use it for I2C adapters from system-on-chip CPUs, |
1700 | * or otherwise built in to the system's mainboard, and where i2c_board_info | |
6e13e641 DB |
1701 | * is used to properly configure I2C devices. |
1702 | * | |
488bf314 GL |
1703 | * If the requested bus number is set to -1, then this function will behave |
1704 | * identically to i2c_add_adapter, and will dynamically assign a bus number. | |
1705 | * | |
6e13e641 DB |
1706 | * If no devices have pre-been declared for this bus, then be sure to |
1707 | * register the adapter before any dynamically allocated ones. Otherwise | |
1708 | * the required bus ID may not be available. | |
1709 | * | |
1710 | * When this returns zero, the specified adapter became available for | |
1711 | * clients using the bus number provided in adap->nr. Also, the table | |
1712 | * of I2C devices pre-declared using i2c_register_board_info() is scanned, | |
1713 | * and the appropriate driver model device nodes are created. Otherwise, a | |
1714 | * negative errno value is returned. | |
1715 | */ | |
1716 | int i2c_add_numbered_adapter(struct i2c_adapter *adap) | |
1717 | { | |
488bf314 GL |
1718 | if (adap->nr == -1) /* -1 means dynamically assign bus id */ |
1719 | return i2c_add_adapter(adap); | |
6e13e641 | 1720 | |
ee5c2744 | 1721 | return __i2c_add_numbered_adapter(adap); |
6e13e641 DB |
1722 | } |
1723 | EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter); | |
1724 | ||
19baba4c | 1725 | static void i2c_do_del_adapter(struct i2c_driver *driver, |
69b0089a | 1726 | struct i2c_adapter *adapter) |
026526f5 | 1727 | { |
4735c98f | 1728 | struct i2c_client *client, *_n; |
026526f5 | 1729 | |
acec211c JD |
1730 | /* Remove the devices we created ourselves as the result of hardware |
1731 | * probing (using a driver's detect method) */ | |
4735c98f JD |
1732 | list_for_each_entry_safe(client, _n, &driver->clients, detected) { |
1733 | if (client->adapter == adapter) { | |
1734 | dev_dbg(&adapter->dev, "Removing %s at 0x%x\n", | |
1735 | client->name, client->addr); | |
1736 | list_del(&client->detected); | |
1737 | i2c_unregister_device(client); | |
1738 | } | |
1739 | } | |
026526f5 JD |
1740 | } |
1741 | ||
e549c2b5 | 1742 | static int __unregister_client(struct device *dev, void *dummy) |
5219bf88 JD |
1743 | { |
1744 | struct i2c_client *client = i2c_verify_client(dev); | |
1745 | if (client && strcmp(client->name, "dummy")) | |
1746 | i2c_unregister_device(client); | |
1747 | return 0; | |
1748 | } | |
1749 | ||
1750 | static int __unregister_dummy(struct device *dev, void *dummy) | |
e549c2b5 JD |
1751 | { |
1752 | struct i2c_client *client = i2c_verify_client(dev); | |
1753 | if (client) | |
1754 | i2c_unregister_device(client); | |
1755 | return 0; | |
1756 | } | |
1757 | ||
69b0089a JD |
1758 | static int __process_removed_adapter(struct device_driver *d, void *data) |
1759 | { | |
19baba4c LPC |
1760 | i2c_do_del_adapter(to_i2c_driver(d), data); |
1761 | return 0; | |
69b0089a JD |
1762 | } |
1763 | ||
d64f73be DB |
1764 | /** |
1765 | * i2c_del_adapter - unregister I2C adapter | |
1766 | * @adap: the adapter being unregistered | |
1767 | * Context: can sleep | |
1768 | * | |
1769 | * This unregisters an I2C adapter which was previously registered | |
1770 | * by @i2c_add_adapter or @i2c_add_numbered_adapter. | |
1771 | */ | |
71546300 | 1772 | void i2c_del_adapter(struct i2c_adapter *adap) |
1da177e4 | 1773 | { |
35fc37f8 | 1774 | struct i2c_adapter *found; |
bbd2d9c9 | 1775 | struct i2c_client *client, *next; |
1da177e4 LT |
1776 | |
1777 | /* First make sure that this adapter was ever added */ | |
35fc37f8 JD |
1778 | mutex_lock(&core_lock); |
1779 | found = idr_find(&i2c_adapter_idr, adap->nr); | |
1780 | mutex_unlock(&core_lock); | |
1781 | if (found != adap) { | |
b6d7b3d1 JD |
1782 | pr_debug("i2c-core: attempting to delete unregistered " |
1783 | "adapter [%s]\n", adap->name); | |
71546300 | 1784 | return; |
1da177e4 LT |
1785 | } |
1786 | ||
5d98e61d | 1787 | acpi_i2c_remove_space_handler(adap); |
026526f5 | 1788 | /* Tell drivers about this removal */ |
35fc37f8 | 1789 | mutex_lock(&core_lock); |
19baba4c | 1790 | bus_for_each_drv(&i2c_bus_type, NULL, adap, |
69b0089a | 1791 | __process_removed_adapter); |
35fc37f8 | 1792 | mutex_unlock(&core_lock); |
1da177e4 | 1793 | |
bbd2d9c9 | 1794 | /* Remove devices instantiated from sysfs */ |
390946b1 JD |
1795 | mutex_lock_nested(&adap->userspace_clients_lock, |
1796 | i2c_adapter_depth(adap)); | |
6629dcff JD |
1797 | list_for_each_entry_safe(client, next, &adap->userspace_clients, |
1798 | detected) { | |
1799 | dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name, | |
1800 | client->addr); | |
1801 | list_del(&client->detected); | |
1802 | i2c_unregister_device(client); | |
bbd2d9c9 | 1803 | } |
dafc50d1 | 1804 | mutex_unlock(&adap->userspace_clients_lock); |
bbd2d9c9 | 1805 | |
e549c2b5 | 1806 | /* Detach any active clients. This can't fail, thus we do not |
5219bf88 JD |
1807 | * check the returned value. This is a two-pass process, because |
1808 | * we can't remove the dummy devices during the first pass: they | |
1809 | * could have been instantiated by real devices wishing to clean | |
1810 | * them up properly, so we give them a chance to do that first. */ | |
19baba4c LPC |
1811 | device_for_each_child(&adap->dev, NULL, __unregister_client); |
1812 | device_for_each_child(&adap->dev, NULL, __unregister_dummy); | |
1da177e4 | 1813 | |
2bb5095a JD |
1814 | #ifdef CONFIG_I2C_COMPAT |
1815 | class_compat_remove_link(i2c_adapter_compat_class, &adap->dev, | |
1816 | adap->dev.parent); | |
1817 | #endif | |
1818 | ||
c5567521 TLSC |
1819 | /* device name is gone after device_unregister */ |
1820 | dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name); | |
1821 | ||
9f924169 WS |
1822 | pm_runtime_disable(&adap->dev); |
1823 | ||
26680ee2 WS |
1824 | /* wait until all references to the device are gone |
1825 | * | |
1826 | * FIXME: This is old code and should ideally be replaced by an | |
1827 | * alternative which results in decoupling the lifetime of the struct | |
1828 | * device from the i2c_adapter, like spi or netdev do. Any solution | |
95cc1e3d | 1829 | * should be thoroughly tested with DEBUG_KOBJECT_RELEASE enabled! |
26680ee2 | 1830 | */ |
1da177e4 | 1831 | init_completion(&adap->dev_released); |
1da177e4 | 1832 | device_unregister(&adap->dev); |
1da177e4 | 1833 | wait_for_completion(&adap->dev_released); |
1da177e4 | 1834 | |
6e13e641 | 1835 | /* free bus id */ |
35fc37f8 | 1836 | mutex_lock(&core_lock); |
1da177e4 | 1837 | idr_remove(&i2c_adapter_idr, adap->nr); |
35fc37f8 | 1838 | mutex_unlock(&core_lock); |
1da177e4 | 1839 | |
bd4bc3db JD |
1840 | /* Clear the device structure in case this adapter is ever going to be |
1841 | added again */ | |
1842 | memset(&adap->dev, 0, sizeof(adap->dev)); | |
1da177e4 | 1843 | } |
c0564606 | 1844 | EXPORT_SYMBOL(i2c_del_adapter); |
1da177e4 | 1845 | |
54177ccf WS |
1846 | /** |
1847 | * i2c_parse_fw_timings - get I2C related timing parameters from firmware | |
1848 | * @dev: The device to scan for I2C timing properties | |
1849 | * @t: the i2c_timings struct to be filled with values | |
1850 | * @use_defaults: bool to use sane defaults derived from the I2C specification | |
1851 | * when properties are not found, otherwise use 0 | |
1852 | * | |
1853 | * Scan the device for the generic I2C properties describing timing parameters | |
1854 | * for the signal and fill the given struct with the results. If a property was | |
1855 | * not found and use_defaults was true, then maximum timings are assumed which | |
1856 | * are derived from the I2C specification. If use_defaults is not used, the | |
1857 | * results will be 0, so drivers can apply their own defaults later. The latter | |
1858 | * is mainly intended for avoiding regressions of existing drivers which want | |
1859 | * to switch to this function. New drivers almost always should use the defaults. | |
1860 | */ | |
1861 | ||
1862 | void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_defaults) | |
1863 | { | |
1864 | int ret; | |
1865 | ||
1866 | memset(t, 0, sizeof(*t)); | |
1867 | ||
1868 | ret = device_property_read_u32(dev, "clock-frequency", &t->bus_freq_hz); | |
1869 | if (ret && use_defaults) | |
1870 | t->bus_freq_hz = 100000; | |
1871 | ||
1872 | ret = device_property_read_u32(dev, "i2c-scl-rising-time-ns", &t->scl_rise_ns); | |
1873 | if (ret && use_defaults) { | |
1874 | if (t->bus_freq_hz <= 100000) | |
1875 | t->scl_rise_ns = 1000; | |
1876 | else if (t->bus_freq_hz <= 400000) | |
1877 | t->scl_rise_ns = 300; | |
1878 | else | |
1879 | t->scl_rise_ns = 120; | |
1880 | } | |
1881 | ||
1882 | ret = device_property_read_u32(dev, "i2c-scl-falling-time-ns", &t->scl_fall_ns); | |
1883 | if (ret && use_defaults) { | |
1884 | if (t->bus_freq_hz <= 400000) | |
1885 | t->scl_fall_ns = 300; | |
1886 | else | |
1887 | t->scl_fall_ns = 120; | |
1888 | } | |
1889 | ||
1890 | device_property_read_u32(dev, "i2c-scl-internal-delay-ns", &t->scl_int_delay_ns); | |
1891 | ||
1892 | ret = device_property_read_u32(dev, "i2c-sda-falling-time-ns", &t->sda_fall_ns); | |
1893 | if (ret && use_defaults) | |
1894 | t->sda_fall_ns = t->scl_fall_ns; | |
1895 | } | |
1896 | EXPORT_SYMBOL_GPL(i2c_parse_fw_timings); | |
1897 | ||
7b4fbc50 DB |
1898 | /* ------------------------------------------------------------------------- */ |
1899 | ||
7ae31482 JD |
1900 | int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *)) |
1901 | { | |
1902 | int res; | |
1903 | ||
1904 | mutex_lock(&core_lock); | |
1905 | res = bus_for_each_dev(&i2c_bus_type, NULL, data, fn); | |
1906 | mutex_unlock(&core_lock); | |
1907 | ||
1908 | return res; | |
1909 | } | |
1910 | EXPORT_SYMBOL_GPL(i2c_for_each_dev); | |
1911 | ||
69b0089a | 1912 | static int __process_new_driver(struct device *dev, void *data) |
7f101a97 | 1913 | { |
4f8cf824 JD |
1914 | if (dev->type != &i2c_adapter_type) |
1915 | return 0; | |
69b0089a | 1916 | return i2c_do_add_adapter(data, to_i2c_adapter(dev)); |
7f101a97 DY |
1917 | } |
1918 | ||
7b4fbc50 DB |
1919 | /* |
1920 | * An i2c_driver is used with one or more i2c_client (device) nodes to access | |
729d6dd5 | 1921 | * i2c slave chips, on a bus instance associated with some i2c_adapter. |
1da177e4 LT |
1922 | */ |
1923 | ||
de59cf9e | 1924 | int i2c_register_driver(struct module *owner, struct i2c_driver *driver) |
1da177e4 | 1925 | { |
7eebcb7c | 1926 | int res; |
1da177e4 | 1927 | |
1d0b19c9 DB |
1928 | /* Can't register until after driver model init */ |
1929 | if (unlikely(WARN_ON(!i2c_bus_type.p))) | |
1930 | return -EAGAIN; | |
1931 | ||
1da177e4 | 1932 | /* add the driver to the list of i2c drivers in the driver core */ |
de59cf9e | 1933 | driver->driver.owner = owner; |
1da177e4 | 1934 | driver->driver.bus = &i2c_bus_type; |
1da177e4 | 1935 | |
729d6dd5 | 1936 | /* When registration returns, the driver core |
6e13e641 DB |
1937 | * will have called probe() for all matching-but-unbound devices. |
1938 | */ | |
1da177e4 LT |
1939 | res = driver_register(&driver->driver); |
1940 | if (res) | |
7eebcb7c | 1941 | return res; |
438d6c2c | 1942 | |
35d8b2e6 | 1943 | pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name); |
1da177e4 | 1944 | |
4735c98f JD |
1945 | INIT_LIST_HEAD(&driver->clients); |
1946 | /* Walk the adapters that are already present */ | |
7ae31482 | 1947 | i2c_for_each_dev(driver, __process_new_driver); |
35fc37f8 | 1948 | |
7f101a97 DY |
1949 | return 0; |
1950 | } | |
1951 | EXPORT_SYMBOL(i2c_register_driver); | |
1952 | ||
69b0089a | 1953 | static int __process_removed_driver(struct device *dev, void *data) |
7f101a97 | 1954 | { |
19baba4c LPC |
1955 | if (dev->type == &i2c_adapter_type) |
1956 | i2c_do_del_adapter(data, to_i2c_adapter(dev)); | |
1957 | return 0; | |
1da177e4 LT |
1958 | } |
1959 | ||
a1d9e6e4 DB |
1960 | /** |
1961 | * i2c_del_driver - unregister I2C driver | |
1962 | * @driver: the driver being unregistered | |
d64f73be | 1963 | * Context: can sleep |
a1d9e6e4 | 1964 | */ |
b3e82096 | 1965 | void i2c_del_driver(struct i2c_driver *driver) |
1da177e4 | 1966 | { |
7ae31482 | 1967 | i2c_for_each_dev(driver, __process_removed_driver); |
1da177e4 LT |
1968 | |
1969 | driver_unregister(&driver->driver); | |
35d8b2e6 | 1970 | pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name); |
1da177e4 | 1971 | } |
c0564606 | 1972 | EXPORT_SYMBOL(i2c_del_driver); |
1da177e4 | 1973 | |
7b4fbc50 DB |
1974 | /* ------------------------------------------------------------------------- */ |
1975 | ||
e48d3319 JD |
1976 | /** |
1977 | * i2c_use_client - increments the reference count of the i2c client structure | |
1978 | * @client: the client being referenced | |
1979 | * | |
1980 | * Each live reference to a client should be refcounted. The driver model does | |
1981 | * that automatically as part of driver binding, so that most drivers don't | |
1982 | * need to do this explicitly: they hold a reference until they're unbound | |
1983 | * from the device. | |
1984 | * | |
1985 | * A pointer to the client with the incremented reference counter is returned. | |
1986 | */ | |
1987 | struct i2c_client *i2c_use_client(struct i2c_client *client) | |
1da177e4 | 1988 | { |
6ea438ec DB |
1989 | if (client && get_device(&client->dev)) |
1990 | return client; | |
1991 | return NULL; | |
1da177e4 | 1992 | } |
c0564606 | 1993 | EXPORT_SYMBOL(i2c_use_client); |
1da177e4 | 1994 | |
e48d3319 JD |
1995 | /** |
1996 | * i2c_release_client - release a use of the i2c client structure | |
1997 | * @client: the client being no longer referenced | |
1998 | * | |
1999 | * Must be called when a user of a client is finished with it. | |
2000 | */ | |
2001 | void i2c_release_client(struct i2c_client *client) | |
1da177e4 | 2002 | { |
6ea438ec DB |
2003 | if (client) |
2004 | put_device(&client->dev); | |
1da177e4 | 2005 | } |
c0564606 | 2006 | EXPORT_SYMBOL(i2c_release_client); |
1da177e4 | 2007 | |
9b766b81 DB |
2008 | struct i2c_cmd_arg { |
2009 | unsigned cmd; | |
2010 | void *arg; | |
2011 | }; | |
2012 | ||
2013 | static int i2c_cmd(struct device *dev, void *_arg) | |
2014 | { | |
2015 | struct i2c_client *client = i2c_verify_client(dev); | |
2016 | struct i2c_cmd_arg *arg = _arg; | |
0acc2b32 LPC |
2017 | struct i2c_driver *driver; |
2018 | ||
2019 | if (!client || !client->dev.driver) | |
2020 | return 0; | |
9b766b81 | 2021 | |
0acc2b32 LPC |
2022 | driver = to_i2c_driver(client->dev.driver); |
2023 | if (driver->command) | |
2024 | driver->command(client, arg->cmd, arg->arg); | |
9b766b81 DB |
2025 | return 0; |
2026 | } | |
2027 | ||
1da177e4 LT |
2028 | void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg) |
2029 | { | |
9b766b81 | 2030 | struct i2c_cmd_arg cmd_arg; |
1da177e4 | 2031 | |
9b766b81 DB |
2032 | cmd_arg.cmd = cmd; |
2033 | cmd_arg.arg = arg; | |
2034 | device_for_each_child(&adap->dev, &cmd_arg, i2c_cmd); | |
1da177e4 | 2035 | } |
c0564606 | 2036 | EXPORT_SYMBOL(i2c_clients_command); |
1da177e4 | 2037 | |
ea7513bb PA |
2038 | #if IS_ENABLED(CONFIG_OF_DYNAMIC) |
2039 | static int of_i2c_notify(struct notifier_block *nb, unsigned long action, | |
2040 | void *arg) | |
2041 | { | |
2042 | struct of_reconfig_data *rd = arg; | |
2043 | struct i2c_adapter *adap; | |
2044 | struct i2c_client *client; | |
2045 | ||
2046 | switch (of_reconfig_get_state_change(action, rd)) { | |
2047 | case OF_RECONFIG_CHANGE_ADD: | |
2048 | adap = of_find_i2c_adapter_by_node(rd->dn->parent); | |
2049 | if (adap == NULL) | |
2050 | return NOTIFY_OK; /* not for us */ | |
2051 | ||
4f001fd3 PA |
2052 | if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) { |
2053 | put_device(&adap->dev); | |
2054 | return NOTIFY_OK; | |
2055 | } | |
2056 | ||
ea7513bb PA |
2057 | client = of_i2c_register_device(adap, rd->dn); |
2058 | put_device(&adap->dev); | |
2059 | ||
2060 | if (IS_ERR(client)) { | |
2061 | pr_err("%s: failed to create for '%s'\n", | |
2062 | __func__, rd->dn->full_name); | |
2063 | return notifier_from_errno(PTR_ERR(client)); | |
2064 | } | |
2065 | break; | |
2066 | case OF_RECONFIG_CHANGE_REMOVE: | |
4f001fd3 PA |
2067 | /* already depopulated? */ |
2068 | if (!of_node_check_flag(rd->dn, OF_POPULATED)) | |
2069 | return NOTIFY_OK; | |
2070 | ||
ea7513bb PA |
2071 | /* find our device by node */ |
2072 | client = of_find_i2c_device_by_node(rd->dn); | |
2073 | if (client == NULL) | |
2074 | return NOTIFY_OK; /* no? not meant for us */ | |
2075 | ||
2076 | /* unregister takes one ref away */ | |
2077 | i2c_unregister_device(client); | |
2078 | ||
2079 | /* and put the reference of the find */ | |
2080 | put_device(&client->dev); | |
2081 | break; | |
2082 | } | |
2083 | ||
2084 | return NOTIFY_OK; | |
2085 | } | |
2086 | static struct notifier_block i2c_of_notifier = { | |
2087 | .notifier_call = of_i2c_notify, | |
2088 | }; | |
2089 | #else | |
2090 | extern struct notifier_block i2c_of_notifier; | |
2091 | #endif /* CONFIG_OF_DYNAMIC */ | |
2092 | ||
1da177e4 LT |
2093 | static int __init i2c_init(void) |
2094 | { | |
2095 | int retval; | |
2096 | ||
03bde7c3 WS |
2097 | retval = of_alias_get_highest_id("i2c"); |
2098 | ||
2099 | down_write(&__i2c_board_lock); | |
2100 | if (retval >= __i2c_first_dynamic_bus_num) | |
2101 | __i2c_first_dynamic_bus_num = retval + 1; | |
2102 | up_write(&__i2c_board_lock); | |
2103 | ||
1da177e4 | 2104 | retval = bus_register(&i2c_bus_type); |
1da177e4 LT |
2105 | if (retval) |
2106 | return retval; | |
2bb5095a JD |
2107 | #ifdef CONFIG_I2C_COMPAT |
2108 | i2c_adapter_compat_class = class_compat_register("i2c-adapter"); | |
2109 | if (!i2c_adapter_compat_class) { | |
2110 | retval = -ENOMEM; | |
2111 | goto bus_err; | |
2112 | } | |
2113 | #endif | |
e9f1373b DB |
2114 | retval = i2c_add_driver(&dummy_driver); |
2115 | if (retval) | |
2bb5095a | 2116 | goto class_err; |
ea7513bb PA |
2117 | |
2118 | if (IS_ENABLED(CONFIG_OF_DYNAMIC)) | |
2119 | WARN_ON(of_reconfig_notifier_register(&i2c_of_notifier)); | |
2120 | ||
e9f1373b DB |
2121 | return 0; |
2122 | ||
2bb5095a JD |
2123 | class_err: |
2124 | #ifdef CONFIG_I2C_COMPAT | |
2125 | class_compat_unregister(i2c_adapter_compat_class); | |
e9f1373b | 2126 | bus_err: |
2bb5095a | 2127 | #endif |
e9f1373b DB |
2128 | bus_unregister(&i2c_bus_type); |
2129 | return retval; | |
1da177e4 LT |
2130 | } |
2131 | ||
2132 | static void __exit i2c_exit(void) | |
2133 | { | |
ea7513bb PA |
2134 | if (IS_ENABLED(CONFIG_OF_DYNAMIC)) |
2135 | WARN_ON(of_reconfig_notifier_unregister(&i2c_of_notifier)); | |
e9f1373b | 2136 | i2c_del_driver(&dummy_driver); |
2bb5095a JD |
2137 | #ifdef CONFIG_I2C_COMPAT |
2138 | class_compat_unregister(i2c_adapter_compat_class); | |
2139 | #endif | |
1da177e4 | 2140 | bus_unregister(&i2c_bus_type); |
d9a83d62 | 2141 | tracepoint_synchronize_unregister(); |
1da177e4 LT |
2142 | } |
2143 | ||
a10f9e7c DB |
2144 | /* We must initialize early, because some subsystems register i2c drivers |
2145 | * in subsys_initcall() code, but are linked (and initialized) before i2c. | |
2146 | */ | |
2147 | postcore_initcall(i2c_init); | |
1da177e4 LT |
2148 | module_exit(i2c_exit); |
2149 | ||
2150 | /* ---------------------------------------------------- | |
2151 | * the functional interface to the i2c busses. | |
2152 | * ---------------------------------------------------- | |
2153 | */ | |
2154 | ||
b7f62584 WS |
2155 | /* Check if val is exceeding the quirk IFF quirk is non 0 */ |
2156 | #define i2c_quirk_exceeded(val, quirk) ((quirk) && ((val) > (quirk))) | |
2157 | ||
2158 | static int i2c_quirk_error(struct i2c_adapter *adap, struct i2c_msg *msg, char *err_msg) | |
2159 | { | |
2160 | dev_err_ratelimited(&adap->dev, "adapter quirk: %s (addr 0x%04x, size %u, %s)\n", | |
2161 | err_msg, msg->addr, msg->len, | |
2162 | msg->flags & I2C_M_RD ? "read" : "write"); | |
2163 | return -EOPNOTSUPP; | |
2164 | } | |
2165 | ||
2166 | static int i2c_check_for_quirks(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) | |
2167 | { | |
2168 | const struct i2c_adapter_quirks *q = adap->quirks; | |
2169 | int max_num = q->max_num_msgs, i; | |
2170 | bool do_len_check = true; | |
2171 | ||
2172 | if (q->flags & I2C_AQ_COMB) { | |
2173 | max_num = 2; | |
2174 | ||
2175 | /* special checks for combined messages */ | |
2176 | if (num == 2) { | |
2177 | if (q->flags & I2C_AQ_COMB_WRITE_FIRST && msgs[0].flags & I2C_M_RD) | |
2178 | return i2c_quirk_error(adap, &msgs[0], "1st comb msg must be write"); | |
2179 | ||
2180 | if (q->flags & I2C_AQ_COMB_READ_SECOND && !(msgs[1].flags & I2C_M_RD)) | |
2181 | return i2c_quirk_error(adap, &msgs[1], "2nd comb msg must be read"); | |
2182 | ||
2183 | if (q->flags & I2C_AQ_COMB_SAME_ADDR && msgs[0].addr != msgs[1].addr) | |
2184 | return i2c_quirk_error(adap, &msgs[0], "comb msg only to same addr"); | |
2185 | ||
2186 | if (i2c_quirk_exceeded(msgs[0].len, q->max_comb_1st_msg_len)) | |
2187 | return i2c_quirk_error(adap, &msgs[0], "msg too long"); | |
2188 | ||
2189 | if (i2c_quirk_exceeded(msgs[1].len, q->max_comb_2nd_msg_len)) | |
2190 | return i2c_quirk_error(adap, &msgs[1], "msg too long"); | |
2191 | ||
2192 | do_len_check = false; | |
2193 | } | |
2194 | } | |
2195 | ||
2196 | if (i2c_quirk_exceeded(num, max_num)) | |
2197 | return i2c_quirk_error(adap, &msgs[0], "too many messages"); | |
2198 | ||
2199 | for (i = 0; i < num; i++) { | |
2200 | u16 len = msgs[i].len; | |
2201 | ||
2202 | if (msgs[i].flags & I2C_M_RD) { | |
2203 | if (do_len_check && i2c_quirk_exceeded(len, q->max_read_len)) | |
2204 | return i2c_quirk_error(adap, &msgs[i], "msg too long"); | |
2205 | } else { | |
2206 | if (do_len_check && i2c_quirk_exceeded(len, q->max_write_len)) | |
2207 | return i2c_quirk_error(adap, &msgs[i], "msg too long"); | |
2208 | } | |
2209 | } | |
2210 | ||
2211 | return 0; | |
2212 | } | |
2213 | ||
b37d2a3a JD |
2214 | /** |
2215 | * __i2c_transfer - unlocked flavor of i2c_transfer | |
2216 | * @adap: Handle to I2C bus | |
2217 | * @msgs: One or more messages to execute before STOP is issued to | |
2218 | * terminate the operation; each message begins with a START. | |
2219 | * @num: Number of messages to be executed. | |
2220 | * | |
2221 | * Returns negative errno, else the number of messages executed. | |
2222 | * | |
2223 | * Adapter lock must be held when calling this function. No debug logging | |
2224 | * takes place. adap->algo->master_xfer existence isn't checked. | |
2225 | */ | |
2226 | int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) | |
2227 | { | |
2228 | unsigned long orig_jiffies; | |
2229 | int ret, try; | |
2230 | ||
b7f62584 WS |
2231 | if (adap->quirks && i2c_check_for_quirks(adap, msgs, num)) |
2232 | return -EOPNOTSUPP; | |
2233 | ||
d9a83d62 DH |
2234 | /* i2c_trace_msg gets enabled when tracepoint i2c_transfer gets |
2235 | * enabled. This is an efficient way of keeping the for-loop from | |
2236 | * being executed when not needed. | |
2237 | */ | |
2238 | if (static_key_false(&i2c_trace_msg)) { | |
2239 | int i; | |
2240 | for (i = 0; i < num; i++) | |
2241 | if (msgs[i].flags & I2C_M_RD) | |
2242 | trace_i2c_read(adap, &msgs[i], i); | |
2243 | else | |
2244 | trace_i2c_write(adap, &msgs[i], i); | |
2245 | } | |
2246 | ||
b37d2a3a JD |
2247 | /* Retry automatically on arbitration loss */ |
2248 | orig_jiffies = jiffies; | |
2249 | for (ret = 0, try = 0; try <= adap->retries; try++) { | |
2250 | ret = adap->algo->master_xfer(adap, msgs, num); | |
2251 | if (ret != -EAGAIN) | |
2252 | break; | |
2253 | if (time_after(jiffies, orig_jiffies + adap->timeout)) | |
2254 | break; | |
2255 | } | |
2256 | ||
d9a83d62 DH |
2257 | if (static_key_false(&i2c_trace_msg)) { |
2258 | int i; | |
2259 | for (i = 0; i < ret; i++) | |
2260 | if (msgs[i].flags & I2C_M_RD) | |
2261 | trace_i2c_reply(adap, &msgs[i], i); | |
2262 | trace_i2c_result(adap, i, ret); | |
2263 | } | |
2264 | ||
b37d2a3a JD |
2265 | return ret; |
2266 | } | |
2267 | EXPORT_SYMBOL(__i2c_transfer); | |
2268 | ||
a1cdedac DB |
2269 | /** |
2270 | * i2c_transfer - execute a single or combined I2C message | |
2271 | * @adap: Handle to I2C bus | |
2272 | * @msgs: One or more messages to execute before STOP is issued to | |
2273 | * terminate the operation; each message begins with a START. | |
2274 | * @num: Number of messages to be executed. | |
2275 | * | |
2276 | * Returns negative errno, else the number of messages executed. | |
2277 | * | |
2278 | * Note that there is no requirement that each message be sent to | |
2279 | * the same slave address, although that is the most common model. | |
2280 | */ | |
09b8ce0a | 2281 | int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) |
1da177e4 | 2282 | { |
b37d2a3a | 2283 | int ret; |
1da177e4 | 2284 | |
a1cdedac DB |
2285 | /* REVISIT the fault reporting model here is weak: |
2286 | * | |
2287 | * - When we get an error after receiving N bytes from a slave, | |
2288 | * there is no way to report "N". | |
2289 | * | |
2290 | * - When we get a NAK after transmitting N bytes to a slave, | |
2291 | * there is no way to report "N" ... or to let the master | |
2292 | * continue executing the rest of this combined message, if | |
2293 | * that's the appropriate response. | |
2294 | * | |
2295 | * - When for example "num" is two and we successfully complete | |
2296 | * the first message but get an error part way through the | |
2297 | * second, it's unclear whether that should be reported as | |
2298 | * one (discarding status on the second message) or errno | |
2299 | * (discarding status on the first one). | |
2300 | */ | |
2301 | ||
1da177e4 LT |
2302 | if (adap->algo->master_xfer) { |
2303 | #ifdef DEBUG | |
2304 | for (ret = 0; ret < num; ret++) { | |
2305 | dev_dbg(&adap->dev, "master_xfer[%d] %c, addr=0x%02x, " | |
209d27c3 JD |
2306 | "len=%d%s\n", ret, (msgs[ret].flags & I2C_M_RD) |
2307 | ? 'R' : 'W', msgs[ret].addr, msgs[ret].len, | |
2308 | (msgs[ret].flags & I2C_M_RECV_LEN) ? "+" : ""); | |
1da177e4 LT |
2309 | } |
2310 | #endif | |
2311 | ||
cea443a8 | 2312 | if (in_atomic() || irqs_disabled()) { |
fe61e07e | 2313 | ret = i2c_trylock_adapter(adap); |
cea443a8 MR |
2314 | if (!ret) |
2315 | /* I2C activity is ongoing. */ | |
2316 | return -EAGAIN; | |
2317 | } else { | |
fe61e07e | 2318 | i2c_lock_adapter(adap); |
cea443a8 MR |
2319 | } |
2320 | ||
b37d2a3a | 2321 | ret = __i2c_transfer(adap, msgs, num); |
fe61e07e | 2322 | i2c_unlock_adapter(adap); |
1da177e4 LT |
2323 | |
2324 | return ret; | |
2325 | } else { | |
2326 | dev_dbg(&adap->dev, "I2C level transfers not supported\n"); | |
24a5bb7b | 2327 | return -EOPNOTSUPP; |
1da177e4 LT |
2328 | } |
2329 | } | |
c0564606 | 2330 | EXPORT_SYMBOL(i2c_transfer); |
1da177e4 | 2331 | |
a1cdedac DB |
2332 | /** |
2333 | * i2c_master_send - issue a single I2C message in master transmit mode | |
2334 | * @client: Handle to slave device | |
2335 | * @buf: Data that will be written to the slave | |
0c43ea54 | 2336 | * @count: How many bytes to write, must be less than 64k since msg.len is u16 |
a1cdedac DB |
2337 | * |
2338 | * Returns negative errno, or else the number of bytes written. | |
2339 | */ | |
0cc43a18 | 2340 | int i2c_master_send(const struct i2c_client *client, const char *buf, int count) |
1da177e4 LT |
2341 | { |
2342 | int ret; | |
7225acf4 | 2343 | struct i2c_adapter *adap = client->adapter; |
1da177e4 LT |
2344 | struct i2c_msg msg; |
2345 | ||
815f55f2 JD |
2346 | msg.addr = client->addr; |
2347 | msg.flags = client->flags & I2C_M_TEN; | |
2348 | msg.len = count; | |
2349 | msg.buf = (char *)buf; | |
438d6c2c | 2350 | |
815f55f2 | 2351 | ret = i2c_transfer(adap, &msg, 1); |
1da177e4 | 2352 | |
834aa6f3 WS |
2353 | /* |
2354 | * If everything went ok (i.e. 1 msg transmitted), return #bytes | |
2355 | * transmitted, else error code. | |
2356 | */ | |
815f55f2 | 2357 | return (ret == 1) ? count : ret; |
1da177e4 | 2358 | } |
c0564606 | 2359 | EXPORT_SYMBOL(i2c_master_send); |
1da177e4 | 2360 | |
a1cdedac DB |
2361 | /** |
2362 | * i2c_master_recv - issue a single I2C message in master receive mode | |
2363 | * @client: Handle to slave device | |
2364 | * @buf: Where to store data read from slave | |
0c43ea54 | 2365 | * @count: How many bytes to read, must be less than 64k since msg.len is u16 |
a1cdedac DB |
2366 | * |
2367 | * Returns negative errno, or else the number of bytes read. | |
2368 | */ | |
0cc43a18 | 2369 | int i2c_master_recv(const struct i2c_client *client, char *buf, int count) |
1da177e4 | 2370 | { |
7225acf4 | 2371 | struct i2c_adapter *adap = client->adapter; |
1da177e4 LT |
2372 | struct i2c_msg msg; |
2373 | int ret; | |
815f55f2 JD |
2374 | |
2375 | msg.addr = client->addr; | |
2376 | msg.flags = client->flags & I2C_M_TEN; | |
2377 | msg.flags |= I2C_M_RD; | |
2378 | msg.len = count; | |
2379 | msg.buf = buf; | |
2380 | ||
2381 | ret = i2c_transfer(adap, &msg, 1); | |
2382 | ||
834aa6f3 WS |
2383 | /* |
2384 | * If everything went ok (i.e. 1 msg received), return #bytes received, | |
2385 | * else error code. | |
2386 | */ | |
815f55f2 | 2387 | return (ret == 1) ? count : ret; |
1da177e4 | 2388 | } |
c0564606 | 2389 | EXPORT_SYMBOL(i2c_master_recv); |
1da177e4 | 2390 | |
1da177e4 LT |
2391 | /* ---------------------------------------------------- |
2392 | * the i2c address scanning function | |
2393 | * Will not work for 10-bit addresses! | |
2394 | * ---------------------------------------------------- | |
2395 | */ | |
1da177e4 | 2396 | |
63e4e802 JD |
2397 | /* |
2398 | * Legacy default probe function, mostly relevant for SMBus. The default | |
2399 | * probe method is a quick write, but it is known to corrupt the 24RF08 | |
2400 | * EEPROMs due to a state machine bug, and could also irreversibly | |
2401 | * write-protect some EEPROMs, so for address ranges 0x30-0x37 and 0x50-0x5f, | |
2402 | * we use a short byte read instead. Also, some bus drivers don't implement | |
2403 | * quick write, so we fallback to a byte read in that case too. | |
2404 | * On x86, there is another special case for FSC hardware monitoring chips, | |
2405 | * which want regular byte reads (address 0x73.) Fortunately, these are the | |
2406 | * only known chips using this I2C address on PC hardware. | |
2407 | * Returns 1 if probe succeeded, 0 if not. | |
2408 | */ | |
2409 | static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr) | |
2410 | { | |
2411 | int err; | |
2412 | union i2c_smbus_data dummy; | |
2413 | ||
2414 | #ifdef CONFIG_X86 | |
2415 | if (addr == 0x73 && (adap->class & I2C_CLASS_HWMON) | |
2416 | && i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE_DATA)) | |
2417 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
2418 | I2C_SMBUS_BYTE_DATA, &dummy); | |
2419 | else | |
2420 | #endif | |
8031d79b JD |
2421 | if (!((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50) |
2422 | && i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) | |
63e4e802 JD |
2423 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0, |
2424 | I2C_SMBUS_QUICK, NULL); | |
8031d79b JD |
2425 | else if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) |
2426 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
2427 | I2C_SMBUS_BYTE, &dummy); | |
2428 | else { | |
d63a9e85 AL |
2429 | dev_warn(&adap->dev, "No suitable probing method supported for address 0x%02X\n", |
2430 | addr); | |
8031d79b JD |
2431 | err = -EOPNOTSUPP; |
2432 | } | |
63e4e802 JD |
2433 | |
2434 | return err >= 0; | |
2435 | } | |
2436 | ||
ccfbbd08 | 2437 | static int i2c_detect_address(struct i2c_client *temp_client, |
4735c98f JD |
2438 | struct i2c_driver *driver) |
2439 | { | |
2440 | struct i2c_board_info info; | |
2441 | struct i2c_adapter *adapter = temp_client->adapter; | |
2442 | int addr = temp_client->addr; | |
2443 | int err; | |
2444 | ||
2445 | /* Make sure the address is valid */ | |
66be6056 | 2446 | err = i2c_check_7bit_addr_validity_strict(addr); |
656b8761 | 2447 | if (err) { |
4735c98f JD |
2448 | dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n", |
2449 | addr); | |
656b8761 | 2450 | return err; |
4735c98f JD |
2451 | } |
2452 | ||
9bccc70a | 2453 | /* Skip if already in use (7 bit, no need to encode flags) */ |
3b5f794b | 2454 | if (i2c_check_addr_busy(adapter, addr)) |
4735c98f JD |
2455 | return 0; |
2456 | ||
ccfbbd08 | 2457 | /* Make sure there is something at this address */ |
63e4e802 JD |
2458 | if (!i2c_default_probe(adapter, addr)) |
2459 | return 0; | |
4735c98f JD |
2460 | |
2461 | /* Finally call the custom detection function */ | |
2462 | memset(&info, 0, sizeof(struct i2c_board_info)); | |
2463 | info.addr = addr; | |
310ec792 | 2464 | err = driver->detect(temp_client, &info); |
4735c98f JD |
2465 | if (err) { |
2466 | /* -ENODEV is returned if the detection fails. We catch it | |
2467 | here as this isn't an error. */ | |
2468 | return err == -ENODEV ? 0 : err; | |
2469 | } | |
2470 | ||
2471 | /* Consistency check */ | |
2472 | if (info.type[0] == '\0') { | |
2473 | dev_err(&adapter->dev, "%s detection function provided " | |
2474 | "no name for 0x%x\n", driver->driver.name, | |
2475 | addr); | |
2476 | } else { | |
2477 | struct i2c_client *client; | |
2478 | ||
2479 | /* Detection succeeded, instantiate the device */ | |
0c176170 WS |
2480 | if (adapter->class & I2C_CLASS_DEPRECATED) |
2481 | dev_warn(&adapter->dev, | |
2482 | "This adapter will soon drop class based instantiation of devices. " | |
2483 | "Please make sure client 0x%02x gets instantiated by other means. " | |
2484 | "Check 'Documentation/i2c/instantiating-devices' for details.\n", | |
2485 | info.addr); | |
2486 | ||
4735c98f JD |
2487 | dev_dbg(&adapter->dev, "Creating %s at 0x%02x\n", |
2488 | info.type, info.addr); | |
2489 | client = i2c_new_device(adapter, &info); | |
2490 | if (client) | |
2491 | list_add_tail(&client->detected, &driver->clients); | |
2492 | else | |
2493 | dev_err(&adapter->dev, "Failed creating %s at 0x%02x\n", | |
2494 | info.type, info.addr); | |
2495 | } | |
2496 | return 0; | |
2497 | } | |
2498 | ||
2499 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver) | |
2500 | { | |
c3813d6a | 2501 | const unsigned short *address_list; |
4735c98f JD |
2502 | struct i2c_client *temp_client; |
2503 | int i, err = 0; | |
2504 | int adap_id = i2c_adapter_id(adapter); | |
2505 | ||
c3813d6a JD |
2506 | address_list = driver->address_list; |
2507 | if (!driver->detect || !address_list) | |
4735c98f JD |
2508 | return 0; |
2509 | ||
45552272 WS |
2510 | /* Warn that the adapter lost class based instantiation */ |
2511 | if (adapter->class == I2C_CLASS_DEPRECATED) { | |
2512 | dev_dbg(&adapter->dev, | |
2513 | "This adapter dropped support for I2C classes and " | |
2514 | "won't auto-detect %s devices anymore. If you need it, check " | |
2515 | "'Documentation/i2c/instantiating-devices' for alternatives.\n", | |
2516 | driver->driver.name); | |
2517 | return 0; | |
2518 | } | |
2519 | ||
51b54ba9 JD |
2520 | /* Stop here if the classes do not match */ |
2521 | if (!(adapter->class & driver->class)) | |
2522 | return 0; | |
2523 | ||
4735c98f JD |
2524 | /* Set up a temporary client to help detect callback */ |
2525 | temp_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL); | |
2526 | if (!temp_client) | |
2527 | return -ENOMEM; | |
2528 | temp_client->adapter = adapter; | |
2529 | ||
c3813d6a | 2530 | for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) { |
4735c98f | 2531 | dev_dbg(&adapter->dev, "found normal entry for adapter %d, " |
c3813d6a JD |
2532 | "addr 0x%02x\n", adap_id, address_list[i]); |
2533 | temp_client->addr = address_list[i]; | |
ccfbbd08 | 2534 | err = i2c_detect_address(temp_client, driver); |
51b54ba9 JD |
2535 | if (unlikely(err)) |
2536 | break; | |
4735c98f JD |
2537 | } |
2538 | ||
4735c98f JD |
2539 | kfree(temp_client); |
2540 | return err; | |
2541 | } | |
2542 | ||
d44f19d5 JD |
2543 | int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr) |
2544 | { | |
2545 | return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
2546 | I2C_SMBUS_QUICK, NULL) >= 0; | |
2547 | } | |
2548 | EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read); | |
2549 | ||
12b5053a JD |
2550 | struct i2c_client * |
2551 | i2c_new_probed_device(struct i2c_adapter *adap, | |
2552 | struct i2c_board_info *info, | |
9a94241a JD |
2553 | unsigned short const *addr_list, |
2554 | int (*probe)(struct i2c_adapter *, unsigned short addr)) | |
12b5053a JD |
2555 | { |
2556 | int i; | |
2557 | ||
8031d79b | 2558 | if (!probe) |
9a94241a | 2559 | probe = i2c_default_probe; |
12b5053a | 2560 | |
12b5053a JD |
2561 | for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { |
2562 | /* Check address validity */ | |
66be6056 | 2563 | if (i2c_check_7bit_addr_validity_strict(addr_list[i]) < 0) { |
12b5053a JD |
2564 | dev_warn(&adap->dev, "Invalid 7-bit address " |
2565 | "0x%02x\n", addr_list[i]); | |
2566 | continue; | |
2567 | } | |
2568 | ||
9bccc70a | 2569 | /* Check address availability (7 bit, no need to encode flags) */ |
3b5f794b | 2570 | if (i2c_check_addr_busy(adap, addr_list[i])) { |
12b5053a JD |
2571 | dev_dbg(&adap->dev, "Address 0x%02x already in " |
2572 | "use, not probing\n", addr_list[i]); | |
2573 | continue; | |
2574 | } | |
2575 | ||
63e4e802 | 2576 | /* Test address responsiveness */ |
9a94241a | 2577 | if (probe(adap, addr_list[i])) |
63e4e802 | 2578 | break; |
12b5053a | 2579 | } |
12b5053a JD |
2580 | |
2581 | if (addr_list[i] == I2C_CLIENT_END) { | |
2582 | dev_dbg(&adap->dev, "Probing failed, no device found\n"); | |
2583 | return NULL; | |
2584 | } | |
2585 | ||
2586 | info->addr = addr_list[i]; | |
2587 | return i2c_new_device(adap, info); | |
2588 | } | |
2589 | EXPORT_SYMBOL_GPL(i2c_new_probed_device); | |
2590 | ||
d735b34d | 2591 | struct i2c_adapter *i2c_get_adapter(int nr) |
1da177e4 | 2592 | { |
1da177e4 | 2593 | struct i2c_adapter *adapter; |
438d6c2c | 2594 | |
caada32a | 2595 | mutex_lock(&core_lock); |
d735b34d | 2596 | adapter = idr_find(&i2c_adapter_idr, nr); |
611e12ea VZ |
2597 | if (!adapter) |
2598 | goto exit; | |
2599 | ||
2600 | if (try_module_get(adapter->owner)) | |
2601 | get_device(&adapter->dev); | |
2602 | else | |
a0920e10 MH |
2603 | adapter = NULL; |
2604 | ||
611e12ea | 2605 | exit: |
caada32a | 2606 | mutex_unlock(&core_lock); |
a0920e10 | 2607 | return adapter; |
1da177e4 | 2608 | } |
c0564606 | 2609 | EXPORT_SYMBOL(i2c_get_adapter); |
1da177e4 LT |
2610 | |
2611 | void i2c_put_adapter(struct i2c_adapter *adap) | |
2612 | { | |
611e12ea VZ |
2613 | if (!adap) |
2614 | return; | |
2615 | ||
2616 | put_device(&adap->dev); | |
2617 | module_put(adap->owner); | |
1da177e4 | 2618 | } |
c0564606 | 2619 | EXPORT_SYMBOL(i2c_put_adapter); |
1da177e4 LT |
2620 | |
2621 | /* The SMBus parts */ | |
2622 | ||
438d6c2c | 2623 | #define POLY (0x1070U << 3) |
09b8ce0a | 2624 | static u8 crc8(u16 data) |
1da177e4 LT |
2625 | { |
2626 | int i; | |
438d6c2c | 2627 | |
7225acf4 | 2628 | for (i = 0; i < 8; i++) { |
438d6c2c | 2629 | if (data & 0x8000) |
1da177e4 LT |
2630 | data = data ^ POLY; |
2631 | data = data << 1; | |
2632 | } | |
2633 | return (u8)(data >> 8); | |
2634 | } | |
2635 | ||
421ef47b JD |
2636 | /* Incremental CRC8 over count bytes in the array pointed to by p */ |
2637 | static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count) | |
1da177e4 LT |
2638 | { |
2639 | int i; | |
2640 | ||
7225acf4 | 2641 | for (i = 0; i < count; i++) |
421ef47b | 2642 | crc = crc8((crc ^ p[i]) << 8); |
1da177e4 LT |
2643 | return crc; |
2644 | } | |
2645 | ||
421ef47b JD |
2646 | /* Assume a 7-bit address, which is reasonable for SMBus */ |
2647 | static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg) | |
1da177e4 | 2648 | { |
421ef47b JD |
2649 | /* The address will be sent first */ |
2650 | u8 addr = (msg->addr << 1) | !!(msg->flags & I2C_M_RD); | |
2651 | pec = i2c_smbus_pec(pec, &addr, 1); | |
2652 | ||
2653 | /* The data buffer follows */ | |
2654 | return i2c_smbus_pec(pec, msg->buf, msg->len); | |
1da177e4 LT |
2655 | } |
2656 | ||
421ef47b JD |
2657 | /* Used for write only transactions */ |
2658 | static inline void i2c_smbus_add_pec(struct i2c_msg *msg) | |
1da177e4 | 2659 | { |
421ef47b JD |
2660 | msg->buf[msg->len] = i2c_smbus_msg_pec(0, msg); |
2661 | msg->len++; | |
1da177e4 LT |
2662 | } |
2663 | ||
421ef47b JD |
2664 | /* Return <0 on CRC error |
2665 | If there was a write before this read (most cases) we need to take the | |
2666 | partial CRC from the write part into account. | |
2667 | Note that this function does modify the message (we need to decrease the | |
2668 | message length to hide the CRC byte from the caller). */ | |
2669 | static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg) | |
1da177e4 | 2670 | { |
421ef47b JD |
2671 | u8 rpec = msg->buf[--msg->len]; |
2672 | cpec = i2c_smbus_msg_pec(cpec, msg); | |
1da177e4 | 2673 | |
1da177e4 LT |
2674 | if (rpec != cpec) { |
2675 | pr_debug("i2c-core: Bad PEC 0x%02x vs. 0x%02x\n", | |
2676 | rpec, cpec); | |
24a5bb7b | 2677 | return -EBADMSG; |
1da177e4 | 2678 | } |
438d6c2c | 2679 | return 0; |
1da177e4 LT |
2680 | } |
2681 | ||
a1cdedac DB |
2682 | /** |
2683 | * i2c_smbus_read_byte - SMBus "receive byte" protocol | |
2684 | * @client: Handle to slave device | |
2685 | * | |
2686 | * This executes the SMBus "receive byte" protocol, returning negative errno | |
2687 | * else the byte received from the device. | |
2688 | */ | |
0cc43a18 | 2689 | s32 i2c_smbus_read_byte(const struct i2c_client *client) |
1da177e4 LT |
2690 | { |
2691 | union i2c_smbus_data data; | |
24a5bb7b DB |
2692 | int status; |
2693 | ||
2694 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
2695 | I2C_SMBUS_READ, 0, | |
2696 | I2C_SMBUS_BYTE, &data); | |
2697 | return (status < 0) ? status : data.byte; | |
1da177e4 | 2698 | } |
c0564606 | 2699 | EXPORT_SYMBOL(i2c_smbus_read_byte); |
1da177e4 | 2700 | |
a1cdedac DB |
2701 | /** |
2702 | * i2c_smbus_write_byte - SMBus "send byte" protocol | |
2703 | * @client: Handle to slave device | |
2704 | * @value: Byte to be sent | |
2705 | * | |
2706 | * This executes the SMBus "send byte" protocol, returning negative errno | |
2707 | * else zero on success. | |
2708 | */ | |
0cc43a18 | 2709 | s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value) |
1da177e4 | 2710 | { |
7225acf4 | 2711 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
421ef47b | 2712 | I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL); |
1da177e4 | 2713 | } |
c0564606 | 2714 | EXPORT_SYMBOL(i2c_smbus_write_byte); |
1da177e4 | 2715 | |
a1cdedac DB |
2716 | /** |
2717 | * i2c_smbus_read_byte_data - SMBus "read byte" protocol | |
2718 | * @client: Handle to slave device | |
2719 | * @command: Byte interpreted by slave | |
2720 | * | |
2721 | * This executes the SMBus "read byte" protocol, returning negative errno | |
2722 | * else a data byte received from the device. | |
2723 | */ | |
0cc43a18 | 2724 | s32 i2c_smbus_read_byte_data(const struct i2c_client *client, u8 command) |
1da177e4 LT |
2725 | { |
2726 | union i2c_smbus_data data; | |
24a5bb7b DB |
2727 | int status; |
2728 | ||
2729 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
2730 | I2C_SMBUS_READ, command, | |
2731 | I2C_SMBUS_BYTE_DATA, &data); | |
2732 | return (status < 0) ? status : data.byte; | |
1da177e4 | 2733 | } |
c0564606 | 2734 | EXPORT_SYMBOL(i2c_smbus_read_byte_data); |
1da177e4 | 2735 | |
a1cdedac DB |
2736 | /** |
2737 | * i2c_smbus_write_byte_data - SMBus "write byte" protocol | |
2738 | * @client: Handle to slave device | |
2739 | * @command: Byte interpreted by slave | |
2740 | * @value: Byte being written | |
2741 | * | |
2742 | * This executes the SMBus "write byte" protocol, returning negative errno | |
2743 | * else zero on success. | |
2744 | */ | |
0cc43a18 JD |
2745 | s32 i2c_smbus_write_byte_data(const struct i2c_client *client, u8 command, |
2746 | u8 value) | |
1da177e4 LT |
2747 | { |
2748 | union i2c_smbus_data data; | |
2749 | data.byte = value; | |
7225acf4 FH |
2750 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2751 | I2C_SMBUS_WRITE, command, | |
2752 | I2C_SMBUS_BYTE_DATA, &data); | |
1da177e4 | 2753 | } |
c0564606 | 2754 | EXPORT_SYMBOL(i2c_smbus_write_byte_data); |
1da177e4 | 2755 | |
a1cdedac DB |
2756 | /** |
2757 | * i2c_smbus_read_word_data - SMBus "read word" protocol | |
2758 | * @client: Handle to slave device | |
2759 | * @command: Byte interpreted by slave | |
2760 | * | |
2761 | * This executes the SMBus "read word" protocol, returning negative errno | |
2762 | * else a 16-bit unsigned "word" received from the device. | |
2763 | */ | |
0cc43a18 | 2764 | s32 i2c_smbus_read_word_data(const struct i2c_client *client, u8 command) |
1da177e4 LT |
2765 | { |
2766 | union i2c_smbus_data data; | |
24a5bb7b DB |
2767 | int status; |
2768 | ||
2769 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
2770 | I2C_SMBUS_READ, command, | |
2771 | I2C_SMBUS_WORD_DATA, &data); | |
2772 | return (status < 0) ? status : data.word; | |
1da177e4 | 2773 | } |
c0564606 | 2774 | EXPORT_SYMBOL(i2c_smbus_read_word_data); |
1da177e4 | 2775 | |
a1cdedac DB |
2776 | /** |
2777 | * i2c_smbus_write_word_data - SMBus "write word" protocol | |
2778 | * @client: Handle to slave device | |
2779 | * @command: Byte interpreted by slave | |
2780 | * @value: 16-bit "word" being written | |
2781 | * | |
2782 | * This executes the SMBus "write word" protocol, returning negative errno | |
2783 | * else zero on success. | |
2784 | */ | |
0cc43a18 JD |
2785 | s32 i2c_smbus_write_word_data(const struct i2c_client *client, u8 command, |
2786 | u16 value) | |
1da177e4 LT |
2787 | { |
2788 | union i2c_smbus_data data; | |
2789 | data.word = value; | |
7225acf4 FH |
2790 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2791 | I2C_SMBUS_WRITE, command, | |
2792 | I2C_SMBUS_WORD_DATA, &data); | |
1da177e4 | 2793 | } |
c0564606 | 2794 | EXPORT_SYMBOL(i2c_smbus_write_word_data); |
1da177e4 | 2795 | |
a64ec07d | 2796 | /** |
a1cdedac | 2797 | * i2c_smbus_read_block_data - SMBus "block read" protocol |
a64ec07d | 2798 | * @client: Handle to slave device |
a1cdedac | 2799 | * @command: Byte interpreted by slave |
a64ec07d DB |
2800 | * @values: Byte array into which data will be read; big enough to hold |
2801 | * the data returned by the slave. SMBus allows at most 32 bytes. | |
2802 | * | |
a1cdedac DB |
2803 | * This executes the SMBus "block read" protocol, returning negative errno |
2804 | * else the number of data bytes in the slave's response. | |
a64ec07d DB |
2805 | * |
2806 | * Note that using this function requires that the client's adapter support | |
2807 | * the I2C_FUNC_SMBUS_READ_BLOCK_DATA functionality. Not all adapter drivers | |
2808 | * support this; its emulation through I2C messaging relies on a specific | |
2809 | * mechanism (I2C_M_RECV_LEN) which may not be implemented. | |
2810 | */ | |
0cc43a18 | 2811 | s32 i2c_smbus_read_block_data(const struct i2c_client *client, u8 command, |
b86a1bc8 JD |
2812 | u8 *values) |
2813 | { | |
2814 | union i2c_smbus_data data; | |
24a5bb7b | 2815 | int status; |
b86a1bc8 | 2816 | |
24a5bb7b DB |
2817 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2818 | I2C_SMBUS_READ, command, | |
2819 | I2C_SMBUS_BLOCK_DATA, &data); | |
2820 | if (status) | |
2821 | return status; | |
b86a1bc8 JD |
2822 | |
2823 | memcpy(values, &data.block[1], data.block[0]); | |
2824 | return data.block[0]; | |
2825 | } | |
2826 | EXPORT_SYMBOL(i2c_smbus_read_block_data); | |
2827 | ||
a1cdedac DB |
2828 | /** |
2829 | * i2c_smbus_write_block_data - SMBus "block write" protocol | |
2830 | * @client: Handle to slave device | |
2831 | * @command: Byte interpreted by slave | |
2832 | * @length: Size of data block; SMBus allows at most 32 bytes | |
2833 | * @values: Byte array which will be written. | |
2834 | * | |
2835 | * This executes the SMBus "block write" protocol, returning negative errno | |
2836 | * else zero on success. | |
2837 | */ | |
0cc43a18 | 2838 | s32 i2c_smbus_write_block_data(const struct i2c_client *client, u8 command, |
46f5ed75 | 2839 | u8 length, const u8 *values) |
1da177e4 LT |
2840 | { |
2841 | union i2c_smbus_data data; | |
7656032b | 2842 | |
1da177e4 LT |
2843 | if (length > I2C_SMBUS_BLOCK_MAX) |
2844 | length = I2C_SMBUS_BLOCK_MAX; | |
1da177e4 | 2845 | data.block[0] = length; |
7656032b | 2846 | memcpy(&data.block[1], values, length); |
7225acf4 FH |
2847 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2848 | I2C_SMBUS_WRITE, command, | |
2849 | I2C_SMBUS_BLOCK_DATA, &data); | |
1da177e4 | 2850 | } |
c0564606 | 2851 | EXPORT_SYMBOL(i2c_smbus_write_block_data); |
1da177e4 LT |
2852 | |
2853 | /* Returns the number of read bytes */ | |
0cc43a18 | 2854 | s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, u8 command, |
4b2643d7 | 2855 | u8 length, u8 *values) |
1da177e4 LT |
2856 | { |
2857 | union i2c_smbus_data data; | |
24a5bb7b | 2858 | int status; |
7656032b | 2859 | |
4b2643d7 JD |
2860 | if (length > I2C_SMBUS_BLOCK_MAX) |
2861 | length = I2C_SMBUS_BLOCK_MAX; | |
2862 | data.block[0] = length; | |
24a5bb7b DB |
2863 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2864 | I2C_SMBUS_READ, command, | |
2865 | I2C_SMBUS_I2C_BLOCK_DATA, &data); | |
2866 | if (status < 0) | |
2867 | return status; | |
7656032b JD |
2868 | |
2869 | memcpy(values, &data.block[1], data.block[0]); | |
2870 | return data.block[0]; | |
1da177e4 | 2871 | } |
c0564606 | 2872 | EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data); |
1da177e4 | 2873 | |
0cc43a18 | 2874 | s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, u8 command, |
46f5ed75 | 2875 | u8 length, const u8 *values) |
21bbd691 JD |
2876 | { |
2877 | union i2c_smbus_data data; | |
2878 | ||
2879 | if (length > I2C_SMBUS_BLOCK_MAX) | |
2880 | length = I2C_SMBUS_BLOCK_MAX; | |
2881 | data.block[0] = length; | |
2882 | memcpy(data.block + 1, values, length); | |
2883 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
2884 | I2C_SMBUS_WRITE, command, | |
2885 | I2C_SMBUS_I2C_BLOCK_DATA, &data); | |
2886 | } | |
c0564606 | 2887 | EXPORT_SYMBOL(i2c_smbus_write_i2c_block_data); |
21bbd691 | 2888 | |
438d6c2c | 2889 | /* Simulate a SMBus command using the i2c protocol |
1da177e4 | 2890 | No checking of parameters is done! */ |
7225acf4 FH |
2891 | static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, |
2892 | unsigned short flags, | |
2893 | char read_write, u8 command, int size, | |
2894 | union i2c_smbus_data *data) | |
1da177e4 LT |
2895 | { |
2896 | /* So we need to generate a series of msgs. In the case of writing, we | |
2897 | need to use only one message; when reading, we need two. We initialize | |
2898 | most things with sane defaults, to keep the code below somewhat | |
2899 | simpler. */ | |
5c50d188 HI |
2900 | unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3]; |
2901 | unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2]; | |
7225acf4 | 2902 | int num = read_write == I2C_SMBUS_READ ? 2 : 1; |
1da177e4 | 2903 | int i; |
421ef47b | 2904 | u8 partial_pec = 0; |
24a5bb7b | 2905 | int status; |
230da094 S |
2906 | struct i2c_msg msg[2] = { |
2907 | { | |
2908 | .addr = addr, | |
2909 | .flags = flags, | |
2910 | .len = 1, | |
2911 | .buf = msgbuf0, | |
2912 | }, { | |
2913 | .addr = addr, | |
2914 | .flags = flags | I2C_M_RD, | |
2915 | .len = 0, | |
2916 | .buf = msgbuf1, | |
2917 | }, | |
2918 | }; | |
1da177e4 LT |
2919 | |
2920 | msgbuf0[0] = command; | |
7225acf4 | 2921 | switch (size) { |
1da177e4 LT |
2922 | case I2C_SMBUS_QUICK: |
2923 | msg[0].len = 0; | |
2924 | /* Special case: The read/write field is used as data */ | |
f29d2e02 RK |
2925 | msg[0].flags = flags | (read_write == I2C_SMBUS_READ ? |
2926 | I2C_M_RD : 0); | |
1da177e4 LT |
2927 | num = 1; |
2928 | break; | |
2929 | case I2C_SMBUS_BYTE: | |
2930 | if (read_write == I2C_SMBUS_READ) { | |
2931 | /* Special case: only a read! */ | |
2932 | msg[0].flags = I2C_M_RD | flags; | |
2933 | num = 1; | |
2934 | } | |
2935 | break; | |
2936 | case I2C_SMBUS_BYTE_DATA: | |
2937 | if (read_write == I2C_SMBUS_READ) | |
2938 | msg[1].len = 1; | |
2939 | else { | |
2940 | msg[0].len = 2; | |
2941 | msgbuf0[1] = data->byte; | |
2942 | } | |
2943 | break; | |
2944 | case I2C_SMBUS_WORD_DATA: | |
2945 | if (read_write == I2C_SMBUS_READ) | |
2946 | msg[1].len = 2; | |
2947 | else { | |
7225acf4 | 2948 | msg[0].len = 3; |
1da177e4 | 2949 | msgbuf0[1] = data->word & 0xff; |
7eff82c8 | 2950 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
2951 | } |
2952 | break; | |
2953 | case I2C_SMBUS_PROC_CALL: | |
2954 | num = 2; /* Special case */ | |
2955 | read_write = I2C_SMBUS_READ; | |
2956 | msg[0].len = 3; | |
2957 | msg[1].len = 2; | |
2958 | msgbuf0[1] = data->word & 0xff; | |
7eff82c8 | 2959 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
2960 | break; |
2961 | case I2C_SMBUS_BLOCK_DATA: | |
1da177e4 | 2962 | if (read_write == I2C_SMBUS_READ) { |
209d27c3 JD |
2963 | msg[1].flags |= I2C_M_RECV_LEN; |
2964 | msg[1].len = 1; /* block length will be added by | |
2965 | the underlying bus driver */ | |
1da177e4 LT |
2966 | } else { |
2967 | msg[0].len = data->block[0] + 2; | |
2968 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 2) { | |
24a5bb7b DB |
2969 | dev_err(&adapter->dev, |
2970 | "Invalid block write size %d\n", | |
2971 | data->block[0]); | |
2972 | return -EINVAL; | |
1da177e4 | 2973 | } |
5c50d188 | 2974 | for (i = 1; i < msg[0].len; i++) |
1da177e4 LT |
2975 | msgbuf0[i] = data->block[i-1]; |
2976 | } | |
2977 | break; | |
2978 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
209d27c3 JD |
2979 | num = 2; /* Another special case */ |
2980 | read_write = I2C_SMBUS_READ; | |
2981 | if (data->block[0] > I2C_SMBUS_BLOCK_MAX) { | |
24a5bb7b DB |
2982 | dev_err(&adapter->dev, |
2983 | "Invalid block write size %d\n", | |
209d27c3 | 2984 | data->block[0]); |
24a5bb7b | 2985 | return -EINVAL; |
209d27c3 JD |
2986 | } |
2987 | msg[0].len = data->block[0] + 2; | |
2988 | for (i = 1; i < msg[0].len; i++) | |
2989 | msgbuf0[i] = data->block[i-1]; | |
2990 | msg[1].flags |= I2C_M_RECV_LEN; | |
2991 | msg[1].len = 1; /* block length will be added by | |
2992 | the underlying bus driver */ | |
2993 | break; | |
1da177e4 LT |
2994 | case I2C_SMBUS_I2C_BLOCK_DATA: |
2995 | if (read_write == I2C_SMBUS_READ) { | |
4b2643d7 | 2996 | msg[1].len = data->block[0]; |
1da177e4 LT |
2997 | } else { |
2998 | msg[0].len = data->block[0] + 1; | |
30dac746 | 2999 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 1) { |
24a5bb7b DB |
3000 | dev_err(&adapter->dev, |
3001 | "Invalid block write size %d\n", | |
3002 | data->block[0]); | |
3003 | return -EINVAL; | |
1da177e4 LT |
3004 | } |
3005 | for (i = 1; i <= data->block[0]; i++) | |
3006 | msgbuf0[i] = data->block[i]; | |
3007 | } | |
3008 | break; | |
3009 | default: | |
24a5bb7b DB |
3010 | dev_err(&adapter->dev, "Unsupported transaction %d\n", size); |
3011 | return -EOPNOTSUPP; | |
1da177e4 LT |
3012 | } |
3013 | ||
421ef47b JD |
3014 | i = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK |
3015 | && size != I2C_SMBUS_I2C_BLOCK_DATA); | |
3016 | if (i) { | |
3017 | /* Compute PEC if first message is a write */ | |
3018 | if (!(msg[0].flags & I2C_M_RD)) { | |
438d6c2c | 3019 | if (num == 1) /* Write only */ |
421ef47b JD |
3020 | i2c_smbus_add_pec(&msg[0]); |
3021 | else /* Write followed by read */ | |
3022 | partial_pec = i2c_smbus_msg_pec(0, &msg[0]); | |
3023 | } | |
3024 | /* Ask for PEC if last message is a read */ | |
3025 | if (msg[num-1].flags & I2C_M_RD) | |
438d6c2c | 3026 | msg[num-1].len++; |
421ef47b JD |
3027 | } |
3028 | ||
24a5bb7b DB |
3029 | status = i2c_transfer(adapter, msg, num); |
3030 | if (status < 0) | |
3031 | return status; | |
1da177e4 | 3032 | |
421ef47b JD |
3033 | /* Check PEC if last message is a read */ |
3034 | if (i && (msg[num-1].flags & I2C_M_RD)) { | |
24a5bb7b DB |
3035 | status = i2c_smbus_check_pec(partial_pec, &msg[num-1]); |
3036 | if (status < 0) | |
3037 | return status; | |
421ef47b JD |
3038 | } |
3039 | ||
1da177e4 | 3040 | if (read_write == I2C_SMBUS_READ) |
7225acf4 FH |
3041 | switch (size) { |
3042 | case I2C_SMBUS_BYTE: | |
3043 | data->byte = msgbuf0[0]; | |
3044 | break; | |
3045 | case I2C_SMBUS_BYTE_DATA: | |
3046 | data->byte = msgbuf1[0]; | |
3047 | break; | |
3048 | case I2C_SMBUS_WORD_DATA: | |
3049 | case I2C_SMBUS_PROC_CALL: | |
3050 | data->word = msgbuf1[0] | (msgbuf1[1] << 8); | |
3051 | break; | |
3052 | case I2C_SMBUS_I2C_BLOCK_DATA: | |
3053 | for (i = 0; i < data->block[0]; i++) | |
3054 | data->block[i+1] = msgbuf1[i]; | |
3055 | break; | |
3056 | case I2C_SMBUS_BLOCK_DATA: | |
3057 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
3058 | for (i = 0; i < msgbuf1[0] + 1; i++) | |
3059 | data->block[i] = msgbuf1[i]; | |
3060 | break; | |
1da177e4 LT |
3061 | } |
3062 | return 0; | |
3063 | } | |
3064 | ||
a1cdedac DB |
3065 | /** |
3066 | * i2c_smbus_xfer - execute SMBus protocol operations | |
3067 | * @adapter: Handle to I2C bus | |
3068 | * @addr: Address of SMBus slave on that bus | |
3069 | * @flags: I2C_CLIENT_* flags (usually zero or I2C_CLIENT_PEC) | |
3070 | * @read_write: I2C_SMBUS_READ or I2C_SMBUS_WRITE | |
3071 | * @command: Byte interpreted by slave, for protocols which use such bytes | |
3072 | * @protocol: SMBus protocol operation to execute, such as I2C_SMBUS_PROC_CALL | |
3073 | * @data: Data to be read or written | |
3074 | * | |
3075 | * This executes an SMBus protocol operation, and returns a negative | |
3076 | * errno code else zero on success. | |
3077 | */ | |
09b8ce0a | 3078 | s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags, |
a1cdedac | 3079 | char read_write, u8 command, int protocol, |
09b8ce0a | 3080 | union i2c_smbus_data *data) |
1da177e4 | 3081 | { |
66b650f0 CW |
3082 | unsigned long orig_jiffies; |
3083 | int try; | |
1da177e4 | 3084 | s32 res; |
1da177e4 | 3085 | |
8a325997 DH |
3086 | /* If enabled, the following two tracepoints are conditional on |
3087 | * read_write and protocol. | |
3088 | */ | |
3089 | trace_smbus_write(adapter, addr, flags, read_write, | |
3090 | command, protocol, data); | |
3091 | trace_smbus_read(adapter, addr, flags, read_write, | |
3092 | command, protocol); | |
3093 | ||
d47726c5 | 3094 | flags &= I2C_M_TEN | I2C_CLIENT_PEC | I2C_CLIENT_SCCB; |
1da177e4 LT |
3095 | |
3096 | if (adapter->algo->smbus_xfer) { | |
fe61e07e | 3097 | i2c_lock_adapter(adapter); |
66b650f0 CW |
3098 | |
3099 | /* Retry automatically on arbitration loss */ | |
3100 | orig_jiffies = jiffies; | |
3101 | for (res = 0, try = 0; try <= adapter->retries; try++) { | |
3102 | res = adapter->algo->smbus_xfer(adapter, addr, flags, | |
3103 | read_write, command, | |
3104 | protocol, data); | |
3105 | if (res != -EAGAIN) | |
3106 | break; | |
3107 | if (time_after(jiffies, | |
3108 | orig_jiffies + adapter->timeout)) | |
3109 | break; | |
3110 | } | |
fe61e07e | 3111 | i2c_unlock_adapter(adapter); |
1da177e4 | 3112 | |
72fc2c7f | 3113 | if (res != -EOPNOTSUPP || !adapter->algo->master_xfer) |
8a325997 | 3114 | goto trace; |
72fc2c7f LP |
3115 | /* |
3116 | * Fall back to i2c_smbus_xfer_emulated if the adapter doesn't | |
3117 | * implement native support for the SMBus operation. | |
3118 | */ | |
3119 | } | |
3120 | ||
8a325997 DH |
3121 | res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write, |
3122 | command, protocol, data); | |
3123 | ||
3124 | trace: | |
3125 | /* If enabled, the reply tracepoint is conditional on read_write. */ | |
3126 | trace_smbus_reply(adapter, addr, flags, read_write, | |
3127 | command, protocol, data); | |
3128 | trace_smbus_result(adapter, addr, flags, read_write, | |
3129 | command, protocol, res); | |
3130 | ||
3131 | return res; | |
1da177e4 | 3132 | } |
1da177e4 | 3133 | EXPORT_SYMBOL(i2c_smbus_xfer); |
1da177e4 | 3134 | |
01eef96e IT |
3135 | /** |
3136 | * i2c_smbus_read_i2c_block_data_or_emulated - read block or emulate | |
3137 | * @client: Handle to slave device | |
3138 | * @command: Byte interpreted by slave | |
3139 | * @length: Size of data block; SMBus allows at most I2C_SMBUS_BLOCK_MAX bytes | |
3140 | * @values: Byte array into which data will be read; big enough to hold | |
3141 | * the data returned by the slave. SMBus allows at most | |
3142 | * I2C_SMBUS_BLOCK_MAX bytes. | |
3143 | * | |
3144 | * This executes the SMBus "block read" protocol if supported by the adapter. | |
3145 | * If block read is not supported, it emulates it using either word or byte | |
3146 | * read protocols depending on availability. | |
3147 | * | |
3148 | * The addresses of the I2C slave device that are accessed with this function | |
3149 | * must be mapped to a linear region, so that a block read will have the same | |
3150 | * effect as a byte read. Before using this function you must double-check | |
3151 | * if the I2C slave does support exchanging a block transfer with a byte | |
3152 | * transfer. | |
3153 | */ | |
3154 | s32 i2c_smbus_read_i2c_block_data_or_emulated(const struct i2c_client *client, | |
3155 | u8 command, u8 length, u8 *values) | |
3156 | { | |
3157 | u8 i = 0; | |
3158 | int status; | |
3159 | ||
3160 | if (length > I2C_SMBUS_BLOCK_MAX) | |
3161 | length = I2C_SMBUS_BLOCK_MAX; | |
3162 | ||
3163 | if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_I2C_BLOCK)) | |
3164 | return i2c_smbus_read_i2c_block_data(client, command, length, values); | |
3165 | ||
3166 | if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA)) | |
3167 | return -EOPNOTSUPP; | |
3168 | ||
3169 | if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_WORD_DATA)) { | |
3170 | while ((i + 2) <= length) { | |
3171 | status = i2c_smbus_read_word_data(client, command + i); | |
3172 | if (status < 0) | |
3173 | return status; | |
3174 | values[i] = status & 0xff; | |
3175 | values[i + 1] = status >> 8; | |
3176 | i += 2; | |
3177 | } | |
3178 | } | |
3179 | ||
3180 | while (i < length) { | |
3181 | status = i2c_smbus_read_byte_data(client, command + i); | |
3182 | if (status < 0) | |
3183 | return status; | |
3184 | values[i] = status; | |
3185 | i++; | |
3186 | } | |
3187 | ||
3188 | return i; | |
3189 | } | |
3190 | EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data_or_emulated); | |
3191 | ||
d5fd120e | 3192 | #if IS_ENABLED(CONFIG_I2C_SLAVE) |
4b1acc43 WS |
3193 | int i2c_slave_register(struct i2c_client *client, i2c_slave_cb_t slave_cb) |
3194 | { | |
3195 | int ret; | |
3196 | ||
0c7cab96 WS |
3197 | if (!client || !slave_cb) { |
3198 | WARN(1, "insufficent data\n"); | |
4b1acc43 | 3199 | return -EINVAL; |
0c7cab96 | 3200 | } |
4b1acc43 | 3201 | |
c6909d6f WS |
3202 | if (!(client->flags & I2C_CLIENT_SLAVE)) |
3203 | dev_warn(&client->dev, "%s: client slave flag not set. You might see address collisions\n", | |
3204 | __func__); | |
3205 | ||
4b1acc43 WS |
3206 | if (!(client->flags & I2C_CLIENT_TEN)) { |
3207 | /* Enforce stricter address checking */ | |
66be6056 | 3208 | ret = i2c_check_7bit_addr_validity_strict(client->addr); |
0c7cab96 WS |
3209 | if (ret) { |
3210 | dev_err(&client->dev, "%s: invalid address\n", __func__); | |
4b1acc43 | 3211 | return ret; |
0c7cab96 | 3212 | } |
4b1acc43 WS |
3213 | } |
3214 | ||
0c7cab96 WS |
3215 | if (!client->adapter->algo->reg_slave) { |
3216 | dev_err(&client->dev, "%s: not supported by adapter\n", __func__); | |
4b1acc43 | 3217 | return -EOPNOTSUPP; |
0c7cab96 | 3218 | } |
4b1acc43 WS |
3219 | |
3220 | client->slave_cb = slave_cb; | |
3221 | ||
3222 | i2c_lock_adapter(client->adapter); | |
3223 | ret = client->adapter->algo->reg_slave(client); | |
3224 | i2c_unlock_adapter(client->adapter); | |
3225 | ||
0c7cab96 | 3226 | if (ret) { |
4b1acc43 | 3227 | client->slave_cb = NULL; |
0c7cab96 WS |
3228 | dev_err(&client->dev, "%s: adapter returned error %d\n", __func__, ret); |
3229 | } | |
4b1acc43 WS |
3230 | |
3231 | return ret; | |
3232 | } | |
3233 | EXPORT_SYMBOL_GPL(i2c_slave_register); | |
3234 | ||
3235 | int i2c_slave_unregister(struct i2c_client *client) | |
3236 | { | |
3237 | int ret; | |
3238 | ||
0c7cab96 WS |
3239 | if (!client->adapter->algo->unreg_slave) { |
3240 | dev_err(&client->dev, "%s: not supported by adapter\n", __func__); | |
4b1acc43 | 3241 | return -EOPNOTSUPP; |
0c7cab96 | 3242 | } |
4b1acc43 WS |
3243 | |
3244 | i2c_lock_adapter(client->adapter); | |
3245 | ret = client->adapter->algo->unreg_slave(client); | |
3246 | i2c_unlock_adapter(client->adapter); | |
3247 | ||
3248 | if (ret == 0) | |
3249 | client->slave_cb = NULL; | |
0c7cab96 WS |
3250 | else |
3251 | dev_err(&client->dev, "%s: adapter returned error %d\n", __func__, ret); | |
4b1acc43 WS |
3252 | |
3253 | return ret; | |
3254 | } | |
3255 | EXPORT_SYMBOL_GPL(i2c_slave_unregister); | |
d5fd120e | 3256 | #endif |
4b1acc43 | 3257 | |
1da177e4 LT |
3258 | MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); |
3259 | MODULE_DESCRIPTION("I2C-Bus main module"); | |
3260 | MODULE_LICENSE("GPL"); |