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 | |
13 | GNU General Public License for more details. | |
14 | ||
15 | You should have received a copy of the GNU General Public License | |
16 | along with this program; if not, write to the Free Software | |
5694f8a8 JD |
17 | Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, |
18 | MA 02110-1301 USA. */ | |
1da177e4 LT |
19 | /* ------------------------------------------------------------------------- */ |
20 | ||
96de0e25 | 21 | /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>. |
1da177e4 | 22 | All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl> |
421ef47b | 23 | SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and |
7c81c60f | 24 | Jean Delvare <jdelvare@suse.de> |
0826374b | 25 | Mux support by Rodolfo Giometti <giometti@enneenne.com> and |
687b81d0 WS |
26 | Michael Lawnick <michael.lawnick.ext@nsn.com> |
27 | OF support is copyright (c) 2008 Jochen Friedrich <jochen@scram.de> | |
28 | (based on a previous patch from Jon Smirl <jonsmirl@gmail.com>) and | |
29 | (c) 2013 Wolfram Sang <wsa@the-dreams.de> | |
30 | */ | |
1da177e4 | 31 | |
1da177e4 LT |
32 | #include <linux/module.h> |
33 | #include <linux/kernel.h> | |
5f9296ba | 34 | #include <linux/delay.h> |
1da177e4 | 35 | #include <linux/errno.h> |
5f9296ba | 36 | #include <linux/gpio.h> |
1da177e4 LT |
37 | #include <linux/slab.h> |
38 | #include <linux/i2c.h> | |
39 | #include <linux/init.h> | |
40 | #include <linux/idr.h> | |
b3585e4f | 41 | #include <linux/mutex.h> |
687b81d0 | 42 | #include <linux/of.h> |
959e85f7 | 43 | #include <linux/of_device.h> |
687b81d0 | 44 | #include <linux/of_irq.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> |
907ddf89 | 50 | #include <linux/acpi.h> |
d9a83d62 | 51 | #include <linux/jump_label.h> |
1da177e4 LT |
52 | #include <asm/uaccess.h> |
53 | ||
9c1600ed DB |
54 | #include "i2c-core.h" |
55 | ||
d9a83d62 DH |
56 | #define CREATE_TRACE_POINTS |
57 | #include <trace/events/i2c.h> | |
1da177e4 | 58 | |
6629dcff | 59 | /* core_lock protects i2c_adapter_idr, and guarantees |
35fc37f8 | 60 | that device detection, deletion of detected devices, and attach_adapter |
19baba4c | 61 | calls are serialized */ |
caada32a | 62 | static DEFINE_MUTEX(core_lock); |
1da177e4 LT |
63 | static DEFINE_IDR(i2c_adapter_idr); |
64 | ||
4f8cf824 | 65 | static struct device_type i2c_client_type; |
4735c98f | 66 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver); |
f37dd80a | 67 | |
d9a83d62 DH |
68 | static struct static_key i2c_trace_msg = STATIC_KEY_INIT_FALSE; |
69 | ||
70 | void i2c_transfer_trace_reg(void) | |
71 | { | |
72 | static_key_slow_inc(&i2c_trace_msg); | |
73 | } | |
74 | ||
75 | void i2c_transfer_trace_unreg(void) | |
76 | { | |
77 | static_key_slow_dec(&i2c_trace_msg); | |
78 | } | |
79 | ||
f37dd80a DB |
80 | /* ------------------------------------------------------------------------- */ |
81 | ||
d2653e92 JD |
82 | static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, |
83 | const struct i2c_client *client) | |
84 | { | |
85 | while (id->name[0]) { | |
86 | if (strcmp(client->name, id->name) == 0) | |
87 | return id; | |
88 | id++; | |
89 | } | |
90 | return NULL; | |
91 | } | |
92 | ||
1da177e4 LT |
93 | static int i2c_device_match(struct device *dev, struct device_driver *drv) |
94 | { | |
51298d12 JD |
95 | struct i2c_client *client = i2c_verify_client(dev); |
96 | struct i2c_driver *driver; | |
97 | ||
98 | if (!client) | |
99 | return 0; | |
7b4fbc50 | 100 | |
959e85f7 GL |
101 | /* Attempt an OF style match */ |
102 | if (of_driver_match_device(dev, drv)) | |
103 | return 1; | |
104 | ||
907ddf89 MW |
105 | /* Then ACPI style match */ |
106 | if (acpi_driver_match_device(dev, drv)) | |
107 | return 1; | |
108 | ||
51298d12 | 109 | driver = to_i2c_driver(drv); |
d2653e92 JD |
110 | /* match on an id table if there is one */ |
111 | if (driver->id_table) | |
112 | return i2c_match_id(driver->id_table, client) != NULL; | |
113 | ||
eb8a7908 | 114 | return 0; |
1da177e4 LT |
115 | } |
116 | ||
7b4fbc50 DB |
117 | |
118 | /* uevent helps with hotplug: modprobe -q $(MODALIAS) */ | |
7eff2e7a | 119 | static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env) |
7b4fbc50 DB |
120 | { |
121 | struct i2c_client *client = to_i2c_client(dev); | |
8c4ff6d0 ZR |
122 | int rc; |
123 | ||
124 | rc = acpi_device_uevent_modalias(dev, env); | |
125 | if (rc != -ENODEV) | |
126 | return rc; | |
7b4fbc50 | 127 | |
eb8a7908 JD |
128 | if (add_uevent_var(env, "MODALIAS=%s%s", |
129 | I2C_MODULE_PREFIX, client->name)) | |
130 | return -ENOMEM; | |
7b4fbc50 DB |
131 | dev_dbg(dev, "uevent\n"); |
132 | return 0; | |
133 | } | |
134 | ||
5f9296ba VK |
135 | /* i2c bus recovery routines */ |
136 | static int get_scl_gpio_value(struct i2c_adapter *adap) | |
137 | { | |
138 | return gpio_get_value(adap->bus_recovery_info->scl_gpio); | |
139 | } | |
140 | ||
141 | static void set_scl_gpio_value(struct i2c_adapter *adap, int val) | |
142 | { | |
143 | gpio_set_value(adap->bus_recovery_info->scl_gpio, val); | |
144 | } | |
145 | ||
146 | static int get_sda_gpio_value(struct i2c_adapter *adap) | |
147 | { | |
148 | return gpio_get_value(adap->bus_recovery_info->sda_gpio); | |
149 | } | |
150 | ||
151 | static int i2c_get_gpios_for_recovery(struct i2c_adapter *adap) | |
152 | { | |
153 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
154 | struct device *dev = &adap->dev; | |
155 | int ret = 0; | |
156 | ||
157 | ret = gpio_request_one(bri->scl_gpio, GPIOF_OPEN_DRAIN | | |
158 | GPIOF_OUT_INIT_HIGH, "i2c-scl"); | |
159 | if (ret) { | |
160 | dev_warn(dev, "Can't get SCL gpio: %d\n", bri->scl_gpio); | |
161 | return ret; | |
162 | } | |
163 | ||
164 | if (bri->get_sda) { | |
165 | if (gpio_request_one(bri->sda_gpio, GPIOF_IN, "i2c-sda")) { | |
166 | /* work without SDA polling */ | |
167 | dev_warn(dev, "Can't get SDA gpio: %d. Not using SDA polling\n", | |
168 | bri->sda_gpio); | |
169 | bri->get_sda = NULL; | |
170 | } | |
171 | } | |
172 | ||
173 | return ret; | |
174 | } | |
175 | ||
176 | static void i2c_put_gpios_for_recovery(struct i2c_adapter *adap) | |
177 | { | |
178 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
179 | ||
180 | if (bri->get_sda) | |
181 | gpio_free(bri->sda_gpio); | |
182 | ||
183 | gpio_free(bri->scl_gpio); | |
184 | } | |
185 | ||
186 | /* | |
187 | * We are generating clock pulses. ndelay() determines durating of clk pulses. | |
188 | * We will generate clock with rate 100 KHz and so duration of both clock levels | |
189 | * is: delay in ns = (10^6 / 100) / 2 | |
190 | */ | |
191 | #define RECOVERY_NDELAY 5000 | |
192 | #define RECOVERY_CLK_CNT 9 | |
193 | ||
194 | static int i2c_generic_recovery(struct i2c_adapter *adap) | |
195 | { | |
196 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
197 | int i = 0, val = 1, ret = 0; | |
198 | ||
199 | if (bri->prepare_recovery) | |
200 | bri->prepare_recovery(bri); | |
201 | ||
202 | /* | |
203 | * By this time SCL is high, as we need to give 9 falling-rising edges | |
204 | */ | |
205 | while (i++ < RECOVERY_CLK_CNT * 2) { | |
206 | if (val) { | |
207 | /* Break if SDA is high */ | |
208 | if (bri->get_sda && bri->get_sda(adap)) | |
209 | break; | |
210 | /* SCL shouldn't be low here */ | |
211 | if (!bri->get_scl(adap)) { | |
212 | dev_err(&adap->dev, | |
213 | "SCL is stuck low, exit recovery\n"); | |
214 | ret = -EBUSY; | |
215 | break; | |
216 | } | |
217 | } | |
218 | ||
219 | val = !val; | |
220 | bri->set_scl(adap, val); | |
221 | ndelay(RECOVERY_NDELAY); | |
222 | } | |
223 | ||
224 | if (bri->unprepare_recovery) | |
225 | bri->unprepare_recovery(bri); | |
226 | ||
227 | return ret; | |
228 | } | |
229 | ||
230 | int i2c_generic_scl_recovery(struct i2c_adapter *adap) | |
231 | { | |
232 | adap->bus_recovery_info->set_scl(adap, 1); | |
233 | return i2c_generic_recovery(adap); | |
234 | } | |
235 | ||
236 | int i2c_generic_gpio_recovery(struct i2c_adapter *adap) | |
237 | { | |
238 | int ret; | |
239 | ||
240 | ret = i2c_get_gpios_for_recovery(adap); | |
241 | if (ret) | |
242 | return ret; | |
243 | ||
244 | ret = i2c_generic_recovery(adap); | |
245 | i2c_put_gpios_for_recovery(adap); | |
246 | ||
247 | return ret; | |
248 | } | |
249 | ||
250 | int i2c_recover_bus(struct i2c_adapter *adap) | |
251 | { | |
252 | if (!adap->bus_recovery_info) | |
253 | return -EOPNOTSUPP; | |
254 | ||
255 | dev_dbg(&adap->dev, "Trying i2c bus recovery\n"); | |
256 | return adap->bus_recovery_info->recover_bus(adap); | |
257 | } | |
258 | ||
f37dd80a | 259 | static int i2c_device_probe(struct device *dev) |
1da177e4 | 260 | { |
51298d12 JD |
261 | struct i2c_client *client = i2c_verify_client(dev); |
262 | struct i2c_driver *driver; | |
50c3304a | 263 | int status; |
7b4fbc50 | 264 | |
51298d12 JD |
265 | if (!client) |
266 | return 0; | |
267 | ||
268 | driver = to_i2c_driver(dev->driver); | |
e0457442 | 269 | if (!driver->probe || !driver->id_table) |
7b4fbc50 | 270 | return -ENODEV; |
0acc2b32 | 271 | |
ee35425c MP |
272 | if (!device_can_wakeup(&client->dev)) |
273 | device_init_wakeup(&client->dev, | |
274 | client->flags & I2C_CLIENT_WAKE); | |
7b4fbc50 | 275 | dev_dbg(dev, "probe\n"); |
d2653e92 | 276 | |
a76e9bd8 | 277 | acpi_dev_pm_attach(&client->dev, true); |
e0457442 | 278 | status = driver->probe(client, i2c_match_id(driver->id_table, client)); |
72fa818e | 279 | if (status) |
a76e9bd8 | 280 | acpi_dev_pm_detach(&client->dev, true); |
72fa818e | 281 | |
50c3304a | 282 | return status; |
f37dd80a | 283 | } |
1da177e4 | 284 | |
f37dd80a DB |
285 | static int i2c_device_remove(struct device *dev) |
286 | { | |
51298d12 | 287 | struct i2c_client *client = i2c_verify_client(dev); |
a1d9e6e4 | 288 | struct i2c_driver *driver; |
72fa818e | 289 | int status = 0; |
a1d9e6e4 | 290 | |
51298d12 | 291 | if (!client || !dev->driver) |
a1d9e6e4 DB |
292 | return 0; |
293 | ||
294 | driver = to_i2c_driver(dev->driver); | |
295 | if (driver->remove) { | |
296 | dev_dbg(dev, "remove\n"); | |
297 | status = driver->remove(client); | |
a1d9e6e4 | 298 | } |
72fa818e | 299 | |
a76e9bd8 | 300 | acpi_dev_pm_detach(&client->dev, true); |
a1d9e6e4 | 301 | return status; |
1da177e4 LT |
302 | } |
303 | ||
f37dd80a | 304 | static void i2c_device_shutdown(struct device *dev) |
1da177e4 | 305 | { |
51298d12 | 306 | struct i2c_client *client = i2c_verify_client(dev); |
f37dd80a DB |
307 | struct i2c_driver *driver; |
308 | ||
51298d12 | 309 | if (!client || !dev->driver) |
f37dd80a DB |
310 | return; |
311 | driver = to_i2c_driver(dev->driver); | |
312 | if (driver->shutdown) | |
51298d12 | 313 | driver->shutdown(client); |
1da177e4 LT |
314 | } |
315 | ||
2f60ba70 RW |
316 | #ifdef CONFIG_PM_SLEEP |
317 | static int i2c_legacy_suspend(struct device *dev, pm_message_t mesg) | |
54067ee2 | 318 | { |
2f60ba70 RW |
319 | struct i2c_client *client = i2c_verify_client(dev); |
320 | struct i2c_driver *driver; | |
54067ee2 | 321 | |
2f60ba70 | 322 | if (!client || !dev->driver) |
54067ee2 | 323 | return 0; |
2f60ba70 RW |
324 | driver = to_i2c_driver(dev->driver); |
325 | if (!driver->suspend) | |
54067ee2 | 326 | return 0; |
2f60ba70 | 327 | return driver->suspend(client, mesg); |
54067ee2 | 328 | } |
329 | ||
2f60ba70 | 330 | static int i2c_legacy_resume(struct device *dev) |
54067ee2 | 331 | { |
2f60ba70 RW |
332 | struct i2c_client *client = i2c_verify_client(dev); |
333 | struct i2c_driver *driver; | |
54067ee2 | 334 | |
2f60ba70 | 335 | if (!client || !dev->driver) |
54067ee2 | 336 | return 0; |
2f60ba70 RW |
337 | driver = to_i2c_driver(dev->driver); |
338 | if (!driver->resume) | |
54067ee2 | 339 | return 0; |
2f60ba70 | 340 | return driver->resume(client); |
54067ee2 | 341 | } |
54067ee2 | 342 | |
2f60ba70 | 343 | static int i2c_device_pm_suspend(struct device *dev) |
6de468ae | 344 | { |
2f60ba70 | 345 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
6de468ae | 346 | |
d529de29 MB |
347 | if (pm) |
348 | return pm_generic_suspend(dev); | |
349 | else | |
350 | return i2c_legacy_suspend(dev, PMSG_SUSPEND); | |
6de468ae MB |
351 | } |
352 | ||
2f60ba70 | 353 | static int i2c_device_pm_resume(struct device *dev) |
6de468ae | 354 | { |
2f60ba70 | 355 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
6de468ae | 356 | |
2f60ba70 | 357 | if (pm) |
d529de29 | 358 | return pm_generic_resume(dev); |
2f60ba70 | 359 | else |
d529de29 | 360 | return i2c_legacy_resume(dev); |
6de468ae | 361 | } |
6de468ae | 362 | |
2f60ba70 | 363 | static int i2c_device_pm_freeze(struct device *dev) |
1da177e4 | 364 | { |
2f60ba70 | 365 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
f37dd80a | 366 | |
d529de29 MB |
367 | if (pm) |
368 | return pm_generic_freeze(dev); | |
369 | else | |
370 | return i2c_legacy_suspend(dev, PMSG_FREEZE); | |
1da177e4 LT |
371 | } |
372 | ||
2f60ba70 | 373 | static int i2c_device_pm_thaw(struct device *dev) |
1da177e4 | 374 | { |
2f60ba70 | 375 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
f37dd80a | 376 | |
d529de29 MB |
377 | if (pm) |
378 | return pm_generic_thaw(dev); | |
379 | else | |
380 | return i2c_legacy_resume(dev); | |
2f60ba70 RW |
381 | } |
382 | ||
383 | static int i2c_device_pm_poweroff(struct device *dev) | |
384 | { | |
385 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; | |
386 | ||
d529de29 MB |
387 | if (pm) |
388 | return pm_generic_poweroff(dev); | |
389 | else | |
390 | return i2c_legacy_suspend(dev, PMSG_HIBERNATE); | |
2f60ba70 RW |
391 | } |
392 | ||
393 | static int i2c_device_pm_restore(struct device *dev) | |
394 | { | |
395 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; | |
2f60ba70 RW |
396 | |
397 | if (pm) | |
d529de29 | 398 | return pm_generic_restore(dev); |
2f60ba70 | 399 | else |
d529de29 | 400 | return i2c_legacy_resume(dev); |
1da177e4 | 401 | } |
2f60ba70 RW |
402 | #else /* !CONFIG_PM_SLEEP */ |
403 | #define i2c_device_pm_suspend NULL | |
404 | #define i2c_device_pm_resume NULL | |
405 | #define i2c_device_pm_freeze NULL | |
406 | #define i2c_device_pm_thaw NULL | |
407 | #define i2c_device_pm_poweroff NULL | |
408 | #define i2c_device_pm_restore NULL | |
409 | #endif /* !CONFIG_PM_SLEEP */ | |
1da177e4 | 410 | |
9c1600ed DB |
411 | static void i2c_client_dev_release(struct device *dev) |
412 | { | |
413 | kfree(to_i2c_client(dev)); | |
414 | } | |
415 | ||
09b8ce0a | 416 | static ssize_t |
4f8cf824 | 417 | show_name(struct device *dev, struct device_attribute *attr, char *buf) |
7b4fbc50 | 418 | { |
4f8cf824 JD |
419 | return sprintf(buf, "%s\n", dev->type == &i2c_client_type ? |
420 | to_i2c_client(dev)->name : to_i2c_adapter(dev)->name); | |
7b4fbc50 DB |
421 | } |
422 | ||
09b8ce0a ZX |
423 | static ssize_t |
424 | show_modalias(struct device *dev, struct device_attribute *attr, char *buf) | |
7b4fbc50 DB |
425 | { |
426 | struct i2c_client *client = to_i2c_client(dev); | |
8c4ff6d0 ZR |
427 | int len; |
428 | ||
429 | len = acpi_device_modalias(dev, buf, PAGE_SIZE -1); | |
430 | if (len != -ENODEV) | |
431 | return len; | |
432 | ||
eb8a7908 | 433 | return sprintf(buf, "%s%s\n", I2C_MODULE_PREFIX, client->name); |
7b4fbc50 DB |
434 | } |
435 | ||
4f8cf824 | 436 | static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); |
51298d12 JD |
437 | static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL); |
438 | ||
439 | static struct attribute *i2c_dev_attrs[] = { | |
440 | &dev_attr_name.attr, | |
7b4fbc50 | 441 | /* modalias helps coldplug: modprobe $(cat .../modalias) */ |
51298d12 JD |
442 | &dev_attr_modalias.attr, |
443 | NULL | |
444 | }; | |
445 | ||
446 | static struct attribute_group i2c_dev_attr_group = { | |
447 | .attrs = i2c_dev_attrs, | |
448 | }; | |
449 | ||
450 | static const struct attribute_group *i2c_dev_attr_groups[] = { | |
451 | &i2c_dev_attr_group, | |
452 | NULL | |
7b4fbc50 DB |
453 | }; |
454 | ||
0b2c3688 | 455 | static const struct dev_pm_ops i2c_device_pm_ops = { |
54067ee2 | 456 | .suspend = i2c_device_pm_suspend, |
457 | .resume = i2c_device_pm_resume, | |
2f60ba70 RW |
458 | .freeze = i2c_device_pm_freeze, |
459 | .thaw = i2c_device_pm_thaw, | |
460 | .poweroff = i2c_device_pm_poweroff, | |
461 | .restore = i2c_device_pm_restore, | |
462 | SET_RUNTIME_PM_OPS( | |
463 | pm_generic_runtime_suspend, | |
464 | pm_generic_runtime_resume, | |
45f0a85c | 465 | NULL |
2f60ba70 | 466 | ) |
54067ee2 | 467 | }; |
468 | ||
e9ca9eb9 | 469 | struct bus_type i2c_bus_type = { |
f37dd80a DB |
470 | .name = "i2c", |
471 | .match = i2c_device_match, | |
472 | .probe = i2c_device_probe, | |
473 | .remove = i2c_device_remove, | |
474 | .shutdown = i2c_device_shutdown, | |
54067ee2 | 475 | .pm = &i2c_device_pm_ops, |
b864c7d5 | 476 | }; |
e9ca9eb9 | 477 | EXPORT_SYMBOL_GPL(i2c_bus_type); |
b864c7d5 | 478 | |
51298d12 JD |
479 | static struct device_type i2c_client_type = { |
480 | .groups = i2c_dev_attr_groups, | |
481 | .uevent = i2c_device_uevent, | |
482 | .release = i2c_client_dev_release, | |
483 | }; | |
484 | ||
9b766b81 DB |
485 | |
486 | /** | |
487 | * i2c_verify_client - return parameter as i2c_client, or NULL | |
488 | * @dev: device, probably from some driver model iterator | |
489 | * | |
490 | * When traversing the driver model tree, perhaps using driver model | |
491 | * iterators like @device_for_each_child(), you can't assume very much | |
492 | * about the nodes you find. Use this function to avoid oopses caused | |
493 | * by wrongly treating some non-I2C device as an i2c_client. | |
494 | */ | |
495 | struct i2c_client *i2c_verify_client(struct device *dev) | |
496 | { | |
51298d12 | 497 | return (dev->type == &i2c_client_type) |
9b766b81 DB |
498 | ? to_i2c_client(dev) |
499 | : NULL; | |
500 | } | |
501 | EXPORT_SYMBOL(i2c_verify_client); | |
502 | ||
503 | ||
3a89db5f | 504 | /* This is a permissive address validity check, I2C address map constraints |
25985edc | 505 | * are purposely not enforced, except for the general call address. */ |
3a89db5f JD |
506 | static int i2c_check_client_addr_validity(const struct i2c_client *client) |
507 | { | |
508 | if (client->flags & I2C_CLIENT_TEN) { | |
509 | /* 10-bit address, all values are valid */ | |
510 | if (client->addr > 0x3ff) | |
511 | return -EINVAL; | |
512 | } else { | |
513 | /* 7-bit address, reject the general call address */ | |
514 | if (client->addr == 0x00 || client->addr > 0x7f) | |
515 | return -EINVAL; | |
516 | } | |
517 | return 0; | |
518 | } | |
519 | ||
656b8761 JD |
520 | /* And this is a strict address validity check, used when probing. If a |
521 | * device uses a reserved address, then it shouldn't be probed. 7-bit | |
522 | * addressing is assumed, 10-bit address devices are rare and should be | |
523 | * explicitly enumerated. */ | |
524 | static int i2c_check_addr_validity(unsigned short addr) | |
525 | { | |
526 | /* | |
527 | * Reserved addresses per I2C specification: | |
528 | * 0x00 General call address / START byte | |
529 | * 0x01 CBUS address | |
530 | * 0x02 Reserved for different bus format | |
531 | * 0x03 Reserved for future purposes | |
532 | * 0x04-0x07 Hs-mode master code | |
533 | * 0x78-0x7b 10-bit slave addressing | |
534 | * 0x7c-0x7f Reserved for future purposes | |
535 | */ | |
536 | if (addr < 0x08 || addr > 0x77) | |
537 | return -EINVAL; | |
538 | return 0; | |
539 | } | |
540 | ||
3b5f794b JD |
541 | static int __i2c_check_addr_busy(struct device *dev, void *addrp) |
542 | { | |
543 | struct i2c_client *client = i2c_verify_client(dev); | |
544 | int addr = *(int *)addrp; | |
545 | ||
546 | if (client && client->addr == addr) | |
547 | return -EBUSY; | |
548 | return 0; | |
549 | } | |
550 | ||
0826374b ML |
551 | /* walk up mux tree */ |
552 | static int i2c_check_mux_parents(struct i2c_adapter *adapter, int addr) | |
553 | { | |
97cc4d49 | 554 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
0826374b ML |
555 | int result; |
556 | ||
557 | result = device_for_each_child(&adapter->dev, &addr, | |
558 | __i2c_check_addr_busy); | |
559 | ||
97cc4d49 JD |
560 | if (!result && parent) |
561 | result = i2c_check_mux_parents(parent, addr); | |
0826374b ML |
562 | |
563 | return result; | |
564 | } | |
565 | ||
566 | /* recurse down mux tree */ | |
567 | static int i2c_check_mux_children(struct device *dev, void *addrp) | |
568 | { | |
569 | int result; | |
570 | ||
571 | if (dev->type == &i2c_adapter_type) | |
572 | result = device_for_each_child(dev, addrp, | |
573 | i2c_check_mux_children); | |
574 | else | |
575 | result = __i2c_check_addr_busy(dev, addrp); | |
576 | ||
577 | return result; | |
578 | } | |
579 | ||
3b5f794b JD |
580 | static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr) |
581 | { | |
97cc4d49 | 582 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
0826374b ML |
583 | int result = 0; |
584 | ||
97cc4d49 JD |
585 | if (parent) |
586 | result = i2c_check_mux_parents(parent, addr); | |
0826374b ML |
587 | |
588 | if (!result) | |
589 | result = device_for_each_child(&adapter->dev, &addr, | |
590 | i2c_check_mux_children); | |
591 | ||
592 | return result; | |
3b5f794b JD |
593 | } |
594 | ||
fe61e07e JD |
595 | /** |
596 | * i2c_lock_adapter - Get exclusive access to an I2C bus segment | |
597 | * @adapter: Target I2C bus segment | |
598 | */ | |
599 | void i2c_lock_adapter(struct i2c_adapter *adapter) | |
600 | { | |
97cc4d49 JD |
601 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
602 | ||
603 | if (parent) | |
604 | i2c_lock_adapter(parent); | |
0826374b ML |
605 | else |
606 | rt_mutex_lock(&adapter->bus_lock); | |
fe61e07e JD |
607 | } |
608 | EXPORT_SYMBOL_GPL(i2c_lock_adapter); | |
609 | ||
610 | /** | |
611 | * i2c_trylock_adapter - Try to get exclusive access to an I2C bus segment | |
612 | * @adapter: Target I2C bus segment | |
613 | */ | |
614 | static int i2c_trylock_adapter(struct i2c_adapter *adapter) | |
615 | { | |
97cc4d49 JD |
616 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
617 | ||
618 | if (parent) | |
619 | return i2c_trylock_adapter(parent); | |
0826374b ML |
620 | else |
621 | return rt_mutex_trylock(&adapter->bus_lock); | |
fe61e07e JD |
622 | } |
623 | ||
624 | /** | |
625 | * i2c_unlock_adapter - Release exclusive access to an I2C bus segment | |
626 | * @adapter: Target I2C bus segment | |
627 | */ | |
628 | void i2c_unlock_adapter(struct i2c_adapter *adapter) | |
629 | { | |
97cc4d49 JD |
630 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
631 | ||
632 | if (parent) | |
633 | i2c_unlock_adapter(parent); | |
0826374b ML |
634 | else |
635 | rt_mutex_unlock(&adapter->bus_lock); | |
fe61e07e JD |
636 | } |
637 | EXPORT_SYMBOL_GPL(i2c_unlock_adapter); | |
638 | ||
70762abb JN |
639 | static void i2c_dev_set_name(struct i2c_adapter *adap, |
640 | struct i2c_client *client) | |
641 | { | |
642 | struct acpi_device *adev = ACPI_COMPANION(&client->dev); | |
643 | ||
644 | if (adev) { | |
645 | dev_set_name(&client->dev, "i2c-%s", acpi_dev_name(adev)); | |
646 | return; | |
647 | } | |
648 | ||
649 | /* For 10-bit clients, add an arbitrary offset to avoid collisions */ | |
650 | dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap), | |
651 | client->addr | ((client->flags & I2C_CLIENT_TEN) | |
652 | ? 0xa000 : 0)); | |
653 | } | |
654 | ||
9c1600ed | 655 | /** |
f8a227e8 | 656 | * i2c_new_device - instantiate an i2c device |
9c1600ed DB |
657 | * @adap: the adapter managing the device |
658 | * @info: describes one I2C device; bus_num is ignored | |
d64f73be | 659 | * Context: can sleep |
9c1600ed | 660 | * |
f8a227e8 JD |
661 | * Create an i2c device. Binding is handled through driver model |
662 | * probe()/remove() methods. A driver may be bound to this device when we | |
663 | * return from this function, or any later moment (e.g. maybe hotplugging will | |
664 | * load the driver module). This call is not appropriate for use by mainboard | |
665 | * initialization logic, which usually runs during an arch_initcall() long | |
666 | * before any i2c_adapter could exist. | |
9c1600ed DB |
667 | * |
668 | * This returns the new i2c client, which may be saved for later use with | |
669 | * i2c_unregister_device(); or NULL to indicate an error. | |
670 | */ | |
671 | struct i2c_client * | |
672 | i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) | |
673 | { | |
674 | struct i2c_client *client; | |
675 | int status; | |
676 | ||
677 | client = kzalloc(sizeof *client, GFP_KERNEL); | |
678 | if (!client) | |
679 | return NULL; | |
680 | ||
681 | client->adapter = adap; | |
682 | ||
683 | client->dev.platform_data = info->platform_data; | |
3bbb835d | 684 | |
11f1f2af AV |
685 | if (info->archdata) |
686 | client->dev.archdata = *info->archdata; | |
687 | ||
ee35425c | 688 | client->flags = info->flags; |
9c1600ed DB |
689 | client->addr = info->addr; |
690 | client->irq = info->irq; | |
691 | ||
9c1600ed DB |
692 | strlcpy(client->name, info->type, sizeof(client->name)); |
693 | ||
3a89db5f JD |
694 | /* Check for address validity */ |
695 | status = i2c_check_client_addr_validity(client); | |
696 | if (status) { | |
697 | dev_err(&adap->dev, "Invalid %d-bit I2C address 0x%02hx\n", | |
698 | client->flags & I2C_CLIENT_TEN ? 10 : 7, client->addr); | |
699 | goto out_err_silent; | |
700 | } | |
701 | ||
f8a227e8 | 702 | /* Check for address business */ |
3b5f794b | 703 | status = i2c_check_addr_busy(adap, client->addr); |
f8a227e8 JD |
704 | if (status) |
705 | goto out_err; | |
706 | ||
707 | client->dev.parent = &client->adapter->dev; | |
708 | client->dev.bus = &i2c_bus_type; | |
51298d12 | 709 | client->dev.type = &i2c_client_type; |
d12d42f7 | 710 | client->dev.of_node = info->of_node; |
7b199811 | 711 | ACPI_COMPANION_SET(&client->dev, info->acpi_node.companion); |
f8a227e8 | 712 | |
70762abb | 713 | i2c_dev_set_name(adap, client); |
f8a227e8 JD |
714 | status = device_register(&client->dev); |
715 | if (status) | |
716 | goto out_err; | |
717 | ||
f8a227e8 JD |
718 | dev_dbg(&adap->dev, "client [%s] registered with bus id %s\n", |
719 | client->name, dev_name(&client->dev)); | |
720 | ||
9c1600ed | 721 | return client; |
f8a227e8 JD |
722 | |
723 | out_err: | |
724 | dev_err(&adap->dev, "Failed to register i2c client %s at 0x%02x " | |
725 | "(%d)\n", client->name, client->addr, status); | |
3a89db5f | 726 | out_err_silent: |
f8a227e8 JD |
727 | kfree(client); |
728 | return NULL; | |
9c1600ed DB |
729 | } |
730 | EXPORT_SYMBOL_GPL(i2c_new_device); | |
731 | ||
732 | ||
733 | /** | |
734 | * i2c_unregister_device - reverse effect of i2c_new_device() | |
735 | * @client: value returned from i2c_new_device() | |
d64f73be | 736 | * Context: can sleep |
9c1600ed DB |
737 | */ |
738 | void i2c_unregister_device(struct i2c_client *client) | |
a1d9e6e4 | 739 | { |
a1d9e6e4 DB |
740 | device_unregister(&client->dev); |
741 | } | |
9c1600ed | 742 | EXPORT_SYMBOL_GPL(i2c_unregister_device); |
a1d9e6e4 DB |
743 | |
744 | ||
60b129d7 JD |
745 | static const struct i2c_device_id dummy_id[] = { |
746 | { "dummy", 0 }, | |
747 | { }, | |
748 | }; | |
749 | ||
d2653e92 JD |
750 | static int dummy_probe(struct i2c_client *client, |
751 | const struct i2c_device_id *id) | |
752 | { | |
753 | return 0; | |
754 | } | |
755 | ||
756 | static int dummy_remove(struct i2c_client *client) | |
e9f1373b DB |
757 | { |
758 | return 0; | |
759 | } | |
760 | ||
761 | static struct i2c_driver dummy_driver = { | |
762 | .driver.name = "dummy", | |
d2653e92 JD |
763 | .probe = dummy_probe, |
764 | .remove = dummy_remove, | |
60b129d7 | 765 | .id_table = dummy_id, |
e9f1373b DB |
766 | }; |
767 | ||
768 | /** | |
769 | * i2c_new_dummy - return a new i2c device bound to a dummy driver | |
770 | * @adapter: the adapter managing the device | |
771 | * @address: seven bit address to be used | |
e9f1373b DB |
772 | * Context: can sleep |
773 | * | |
774 | * This returns an I2C client bound to the "dummy" driver, intended for use | |
775 | * with devices that consume multiple addresses. Examples of such chips | |
776 | * include various EEPROMS (like 24c04 and 24c08 models). | |
777 | * | |
778 | * These dummy devices have two main uses. First, most I2C and SMBus calls | |
779 | * except i2c_transfer() need a client handle; the dummy will be that handle. | |
780 | * And second, this prevents the specified address from being bound to a | |
781 | * different driver. | |
782 | * | |
783 | * This returns the new i2c client, which should be saved for later use with | |
784 | * i2c_unregister_device(); or NULL to indicate an error. | |
785 | */ | |
09b8ce0a | 786 | struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) |
e9f1373b DB |
787 | { |
788 | struct i2c_board_info info = { | |
60b129d7 | 789 | I2C_BOARD_INFO("dummy", address), |
e9f1373b DB |
790 | }; |
791 | ||
e9f1373b DB |
792 | return i2c_new_device(adapter, &info); |
793 | } | |
794 | EXPORT_SYMBOL_GPL(i2c_new_dummy); | |
795 | ||
f37dd80a DB |
796 | /* ------------------------------------------------------------------------- */ |
797 | ||
16ffadfc DB |
798 | /* I2C bus adapters -- one roots each I2C or SMBUS segment */ |
799 | ||
83eaaed0 | 800 | static void i2c_adapter_dev_release(struct device *dev) |
1da177e4 | 801 | { |
ef2c8321 | 802 | struct i2c_adapter *adap = to_i2c_adapter(dev); |
1da177e4 LT |
803 | complete(&adap->dev_released); |
804 | } | |
805 | ||
390946b1 JD |
806 | /* |
807 | * This function is only needed for mutex_lock_nested, so it is never | |
808 | * called unless locking correctness checking is enabled. Thus we | |
809 | * make it inline to avoid a compiler warning. That's what gcc ends up | |
810 | * doing anyway. | |
811 | */ | |
812 | static inline unsigned int i2c_adapter_depth(struct i2c_adapter *adapter) | |
813 | { | |
814 | unsigned int depth = 0; | |
815 | ||
816 | while ((adapter = i2c_parent_is_i2c_adapter(adapter))) | |
817 | depth++; | |
818 | ||
819 | return depth; | |
820 | } | |
821 | ||
99cd8e25 JD |
822 | /* |
823 | * Let users instantiate I2C devices through sysfs. This can be used when | |
824 | * platform initialization code doesn't contain the proper data for | |
825 | * whatever reason. Also useful for drivers that do device detection and | |
826 | * detection fails, either because the device uses an unexpected address, | |
827 | * or this is a compatible device with different ID register values. | |
828 | * | |
829 | * Parameter checking may look overzealous, but we really don't want | |
830 | * the user to provide incorrect parameters. | |
831 | */ | |
832 | static ssize_t | |
833 | i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr, | |
834 | const char *buf, size_t count) | |
835 | { | |
836 | struct i2c_adapter *adap = to_i2c_adapter(dev); | |
837 | struct i2c_board_info info; | |
838 | struct i2c_client *client; | |
839 | char *blank, end; | |
840 | int res; | |
841 | ||
99cd8e25 JD |
842 | memset(&info, 0, sizeof(struct i2c_board_info)); |
843 | ||
844 | blank = strchr(buf, ' '); | |
845 | if (!blank) { | |
846 | dev_err(dev, "%s: Missing parameters\n", "new_device"); | |
847 | return -EINVAL; | |
848 | } | |
849 | if (blank - buf > I2C_NAME_SIZE - 1) { | |
850 | dev_err(dev, "%s: Invalid device name\n", "new_device"); | |
851 | return -EINVAL; | |
852 | } | |
853 | memcpy(info.type, buf, blank - buf); | |
854 | ||
855 | /* Parse remaining parameters, reject extra parameters */ | |
856 | res = sscanf(++blank, "%hi%c", &info.addr, &end); | |
857 | if (res < 1) { | |
858 | dev_err(dev, "%s: Can't parse I2C address\n", "new_device"); | |
859 | return -EINVAL; | |
860 | } | |
861 | if (res > 1 && end != '\n') { | |
862 | dev_err(dev, "%s: Extra parameters\n", "new_device"); | |
863 | return -EINVAL; | |
864 | } | |
865 | ||
99cd8e25 JD |
866 | client = i2c_new_device(adap, &info); |
867 | if (!client) | |
3a89db5f | 868 | return -EINVAL; |
99cd8e25 JD |
869 | |
870 | /* Keep track of the added device */ | |
dafc50d1 | 871 | mutex_lock(&adap->userspace_clients_lock); |
6629dcff | 872 | list_add_tail(&client->detected, &adap->userspace_clients); |
dafc50d1 | 873 | mutex_unlock(&adap->userspace_clients_lock); |
99cd8e25 JD |
874 | dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device", |
875 | info.type, info.addr); | |
876 | ||
877 | return count; | |
878 | } | |
879 | ||
880 | /* | |
881 | * And of course let the users delete the devices they instantiated, if | |
882 | * they got it wrong. This interface can only be used to delete devices | |
883 | * instantiated by i2c_sysfs_new_device above. This guarantees that we | |
884 | * don't delete devices to which some kernel code still has references. | |
885 | * | |
886 | * Parameter checking may look overzealous, but we really don't want | |
887 | * the user to delete the wrong device. | |
888 | */ | |
889 | static ssize_t | |
890 | i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr, | |
891 | const char *buf, size_t count) | |
892 | { | |
893 | struct i2c_adapter *adap = to_i2c_adapter(dev); | |
894 | struct i2c_client *client, *next; | |
895 | unsigned short addr; | |
896 | char end; | |
897 | int res; | |
898 | ||
899 | /* Parse parameters, reject extra parameters */ | |
900 | res = sscanf(buf, "%hi%c", &addr, &end); | |
901 | if (res < 1) { | |
902 | dev_err(dev, "%s: Can't parse I2C address\n", "delete_device"); | |
903 | return -EINVAL; | |
904 | } | |
905 | if (res > 1 && end != '\n') { | |
906 | dev_err(dev, "%s: Extra parameters\n", "delete_device"); | |
907 | return -EINVAL; | |
908 | } | |
909 | ||
910 | /* Make sure the device was added through sysfs */ | |
911 | res = -ENOENT; | |
390946b1 JD |
912 | mutex_lock_nested(&adap->userspace_clients_lock, |
913 | i2c_adapter_depth(adap)); | |
6629dcff JD |
914 | list_for_each_entry_safe(client, next, &adap->userspace_clients, |
915 | detected) { | |
916 | if (client->addr == addr) { | |
99cd8e25 JD |
917 | dev_info(dev, "%s: Deleting device %s at 0x%02hx\n", |
918 | "delete_device", client->name, client->addr); | |
919 | ||
920 | list_del(&client->detected); | |
921 | i2c_unregister_device(client); | |
922 | res = count; | |
923 | break; | |
924 | } | |
925 | } | |
dafc50d1 | 926 | mutex_unlock(&adap->userspace_clients_lock); |
99cd8e25 JD |
927 | |
928 | if (res < 0) | |
929 | dev_err(dev, "%s: Can't find device in list\n", | |
930 | "delete_device"); | |
931 | return res; | |
932 | } | |
933 | ||
4f8cf824 | 934 | static DEVICE_ATTR(new_device, S_IWUSR, NULL, i2c_sysfs_new_device); |
e9b526fe AS |
935 | static DEVICE_ATTR_IGNORE_LOCKDEP(delete_device, S_IWUSR, NULL, |
936 | i2c_sysfs_delete_device); | |
4f8cf824 JD |
937 | |
938 | static struct attribute *i2c_adapter_attrs[] = { | |
939 | &dev_attr_name.attr, | |
940 | &dev_attr_new_device.attr, | |
941 | &dev_attr_delete_device.attr, | |
942 | NULL | |
943 | }; | |
944 | ||
945 | static struct attribute_group i2c_adapter_attr_group = { | |
946 | .attrs = i2c_adapter_attrs, | |
947 | }; | |
948 | ||
949 | static const struct attribute_group *i2c_adapter_attr_groups[] = { | |
950 | &i2c_adapter_attr_group, | |
951 | NULL | |
16ffadfc | 952 | }; |
b119dc3f | 953 | |
0826374b | 954 | struct device_type i2c_adapter_type = { |
4f8cf824 JD |
955 | .groups = i2c_adapter_attr_groups, |
956 | .release = i2c_adapter_dev_release, | |
1da177e4 | 957 | }; |
0826374b | 958 | EXPORT_SYMBOL_GPL(i2c_adapter_type); |
1da177e4 | 959 | |
643dd09e SW |
960 | /** |
961 | * i2c_verify_adapter - return parameter as i2c_adapter or NULL | |
962 | * @dev: device, probably from some driver model iterator | |
963 | * | |
964 | * When traversing the driver model tree, perhaps using driver model | |
965 | * iterators like @device_for_each_child(), you can't assume very much | |
966 | * about the nodes you find. Use this function to avoid oopses caused | |
967 | * by wrongly treating some non-I2C device as an i2c_adapter. | |
968 | */ | |
969 | struct i2c_adapter *i2c_verify_adapter(struct device *dev) | |
970 | { | |
971 | return (dev->type == &i2c_adapter_type) | |
972 | ? to_i2c_adapter(dev) | |
973 | : NULL; | |
974 | } | |
975 | EXPORT_SYMBOL(i2c_verify_adapter); | |
976 | ||
2bb5095a JD |
977 | #ifdef CONFIG_I2C_COMPAT |
978 | static struct class_compat *i2c_adapter_compat_class; | |
979 | #endif | |
980 | ||
9c1600ed DB |
981 | static void i2c_scan_static_board_info(struct i2c_adapter *adapter) |
982 | { | |
983 | struct i2c_devinfo *devinfo; | |
984 | ||
f18c41da | 985 | down_read(&__i2c_board_lock); |
9c1600ed DB |
986 | list_for_each_entry(devinfo, &__i2c_board_list, list) { |
987 | if (devinfo->busnum == adapter->nr | |
988 | && !i2c_new_device(adapter, | |
989 | &devinfo->board_info)) | |
09b8ce0a ZX |
990 | dev_err(&adapter->dev, |
991 | "Can't create device at 0x%02x\n", | |
9c1600ed DB |
992 | devinfo->board_info.addr); |
993 | } | |
f18c41da | 994 | up_read(&__i2c_board_lock); |
9c1600ed DB |
995 | } |
996 | ||
687b81d0 WS |
997 | /* OF support code */ |
998 | ||
999 | #if IS_ENABLED(CONFIG_OF) | |
1000 | static void of_i2c_register_devices(struct i2c_adapter *adap) | |
1001 | { | |
1002 | void *result; | |
1003 | struct device_node *node; | |
1004 | ||
1005 | /* Only register child devices if the adapter has a node pointer set */ | |
1006 | if (!adap->dev.of_node) | |
1007 | return; | |
1008 | ||
1009 | dev_dbg(&adap->dev, "of_i2c: walking child nodes\n"); | |
1010 | ||
1011 | for_each_available_child_of_node(adap->dev.of_node, node) { | |
1012 | struct i2c_board_info info = {}; | |
1013 | struct dev_archdata dev_ad = {}; | |
1014 | const __be32 *addr; | |
1015 | int len; | |
1016 | ||
1017 | dev_dbg(&adap->dev, "of_i2c: register %s\n", node->full_name); | |
1018 | ||
1019 | if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) { | |
1020 | dev_err(&adap->dev, "of_i2c: modalias failure on %s\n", | |
1021 | node->full_name); | |
1022 | continue; | |
1023 | } | |
1024 | ||
1025 | addr = of_get_property(node, "reg", &len); | |
1026 | if (!addr || (len < sizeof(int))) { | |
1027 | dev_err(&adap->dev, "of_i2c: invalid reg on %s\n", | |
1028 | node->full_name); | |
1029 | continue; | |
1030 | } | |
1031 | ||
1032 | info.addr = be32_to_cpup(addr); | |
1033 | if (info.addr > (1 << 10) - 1) { | |
1034 | dev_err(&adap->dev, "of_i2c: invalid addr=%x on %s\n", | |
1035 | info.addr, node->full_name); | |
1036 | continue; | |
1037 | } | |
1038 | ||
1039 | info.irq = irq_of_parse_and_map(node, 0); | |
1040 | info.of_node = of_node_get(node); | |
1041 | info.archdata = &dev_ad; | |
1042 | ||
1043 | if (of_get_property(node, "wakeup-source", NULL)) | |
1044 | info.flags |= I2C_CLIENT_WAKE; | |
1045 | ||
1046 | request_module("%s%s", I2C_MODULE_PREFIX, info.type); | |
1047 | ||
1048 | result = i2c_new_device(adap, &info); | |
1049 | if (result == NULL) { | |
1050 | dev_err(&adap->dev, "of_i2c: Failure registering %s\n", | |
1051 | node->full_name); | |
1052 | of_node_put(node); | |
1053 | irq_dispose_mapping(info.irq); | |
1054 | continue; | |
1055 | } | |
1056 | } | |
1057 | } | |
1058 | ||
1059 | static int of_dev_node_match(struct device *dev, void *data) | |
1060 | { | |
1061 | return dev->of_node == data; | |
1062 | } | |
1063 | ||
1064 | /* must call put_device() when done with returned i2c_client device */ | |
1065 | struct i2c_client *of_find_i2c_device_by_node(struct device_node *node) | |
1066 | { | |
1067 | struct device *dev; | |
1068 | ||
1069 | dev = bus_find_device(&i2c_bus_type, NULL, node, | |
1070 | of_dev_node_match); | |
1071 | if (!dev) | |
1072 | return NULL; | |
1073 | ||
1074 | return i2c_verify_client(dev); | |
1075 | } | |
1076 | EXPORT_SYMBOL(of_find_i2c_device_by_node); | |
1077 | ||
1078 | /* must call put_device() when done with returned i2c_adapter device */ | |
1079 | struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node) | |
1080 | { | |
1081 | struct device *dev; | |
1082 | ||
1083 | dev = bus_find_device(&i2c_bus_type, NULL, node, | |
1084 | of_dev_node_match); | |
1085 | if (!dev) | |
1086 | return NULL; | |
1087 | ||
1088 | return i2c_verify_adapter(dev); | |
1089 | } | |
1090 | EXPORT_SYMBOL(of_find_i2c_adapter_by_node); | |
1091 | #else | |
1092 | static void of_i2c_register_devices(struct i2c_adapter *adap) { } | |
1093 | #endif /* CONFIG_OF */ | |
1094 | ||
55e71edb MW |
1095 | /* ACPI support code */ |
1096 | ||
1097 | #if IS_ENABLED(CONFIG_ACPI) | |
1098 | static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data) | |
1099 | { | |
1100 | struct i2c_board_info *info = data; | |
1101 | ||
1102 | if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) { | |
1103 | struct acpi_resource_i2c_serialbus *sb; | |
1104 | ||
1105 | sb = &ares->data.i2c_serial_bus; | |
1106 | if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) { | |
1107 | info->addr = sb->slave_address; | |
1108 | if (sb->access_mode == ACPI_I2C_10BIT_MODE) | |
1109 | info->flags |= I2C_CLIENT_TEN; | |
1110 | } | |
1111 | } else if (info->irq < 0) { | |
1112 | struct resource r; | |
1113 | ||
1114 | if (acpi_dev_resource_interrupt(ares, 0, &r)) | |
1115 | info->irq = r.start; | |
1116 | } | |
1117 | ||
1118 | /* Tell the ACPI core to skip this resource */ | |
1119 | return 1; | |
1120 | } | |
1121 | ||
1122 | static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level, | |
1123 | void *data, void **return_value) | |
1124 | { | |
1125 | struct i2c_adapter *adapter = data; | |
1126 | struct list_head resource_list; | |
1127 | struct i2c_board_info info; | |
1128 | struct acpi_device *adev; | |
1129 | int ret; | |
1130 | ||
1131 | if (acpi_bus_get_device(handle, &adev)) | |
1132 | return AE_OK; | |
1133 | if (acpi_bus_get_status(adev) || !adev->status.present) | |
1134 | return AE_OK; | |
1135 | ||
1136 | memset(&info, 0, sizeof(info)); | |
7b199811 | 1137 | info.acpi_node.companion = adev; |
55e71edb MW |
1138 | info.irq = -1; |
1139 | ||
1140 | INIT_LIST_HEAD(&resource_list); | |
1141 | ret = acpi_dev_get_resources(adev, &resource_list, | |
1142 | acpi_i2c_add_resource, &info); | |
1143 | acpi_dev_free_resource_list(&resource_list); | |
1144 | ||
1145 | if (ret < 0 || !info.addr) | |
1146 | return AE_OK; | |
1147 | ||
a76e9bd8 | 1148 | adev->power.flags.ignore_parent = true; |
55e71edb MW |
1149 | strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type)); |
1150 | if (!i2c_new_device(adapter, &info)) { | |
a76e9bd8 | 1151 | adev->power.flags.ignore_parent = false; |
55e71edb MW |
1152 | dev_err(&adapter->dev, |
1153 | "failed to add I2C device %s from ACPI\n", | |
1154 | dev_name(&adev->dev)); | |
1155 | } | |
1156 | ||
1157 | return AE_OK; | |
1158 | } | |
1159 | ||
1160 | /** | |
1161 | * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter | |
1162 | * @adap: pointer to adapter | |
1163 | * | |
1164 | * Enumerate all I2C slave devices behind this adapter by walking the ACPI | |
1165 | * namespace. When a device is found it will be added to the Linux device | |
1166 | * model and bound to the corresponding ACPI handle. | |
1167 | */ | |
1168 | static void acpi_i2c_register_devices(struct i2c_adapter *adap) | |
1169 | { | |
1170 | acpi_handle handle; | |
1171 | acpi_status status; | |
1172 | ||
47b6e477 JD |
1173 | if (!adap->dev.parent) |
1174 | return; | |
1175 | ||
55e71edb MW |
1176 | handle = ACPI_HANDLE(adap->dev.parent); |
1177 | if (!handle) | |
1178 | return; | |
1179 | ||
1180 | status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, | |
1181 | acpi_i2c_add_device, NULL, | |
1182 | adap, NULL); | |
1183 | if (ACPI_FAILURE(status)) | |
1184 | dev_warn(&adap->dev, "failed to enumerate I2C slaves\n"); | |
1185 | } | |
1186 | #else | |
1187 | static inline void acpi_i2c_register_devices(struct i2c_adapter *adap) {} | |
1188 | #endif /* CONFIG_ACPI */ | |
1189 | ||
69b0089a JD |
1190 | static int i2c_do_add_adapter(struct i2c_driver *driver, |
1191 | struct i2c_adapter *adap) | |
026526f5 | 1192 | { |
4735c98f JD |
1193 | /* Detect supported devices on that bus, and instantiate them */ |
1194 | i2c_detect(adap, driver); | |
1195 | ||
1196 | /* Let legacy drivers scan this bus for matching devices */ | |
026526f5 | 1197 | if (driver->attach_adapter) { |
a920ff41 JD |
1198 | dev_warn(&adap->dev, "%s: attach_adapter method is deprecated\n", |
1199 | driver->driver.name); | |
fe6fc258 JD |
1200 | dev_warn(&adap->dev, "Please use another way to instantiate " |
1201 | "your i2c_client\n"); | |
026526f5 JD |
1202 | /* We ignore the return code; if it fails, too bad */ |
1203 | driver->attach_adapter(adap); | |
1204 | } | |
1205 | return 0; | |
1206 | } | |
1207 | ||
69b0089a JD |
1208 | static int __process_new_adapter(struct device_driver *d, void *data) |
1209 | { | |
1210 | return i2c_do_add_adapter(to_i2c_driver(d), data); | |
1211 | } | |
1212 | ||
6e13e641 | 1213 | static int i2c_register_adapter(struct i2c_adapter *adap) |
1da177e4 | 1214 | { |
d6703281 | 1215 | int res = 0; |
1da177e4 | 1216 | |
1d0b19c9 | 1217 | /* Can't register until after driver model init */ |
35fc37f8 JD |
1218 | if (unlikely(WARN_ON(!i2c_bus_type.p))) { |
1219 | res = -EAGAIN; | |
1220 | goto out_list; | |
1221 | } | |
1d0b19c9 | 1222 | |
2236baa7 JD |
1223 | /* Sanity checks */ |
1224 | if (unlikely(adap->name[0] == '\0')) { | |
1225 | pr_err("i2c-core: Attempt to register an adapter with " | |
1226 | "no name!\n"); | |
1227 | return -EINVAL; | |
1228 | } | |
1229 | if (unlikely(!adap->algo)) { | |
1230 | pr_err("i2c-core: Attempt to register adapter '%s' with " | |
1231 | "no algo!\n", adap->name); | |
1232 | return -EINVAL; | |
1233 | } | |
1234 | ||
194684e5 | 1235 | rt_mutex_init(&adap->bus_lock); |
dafc50d1 | 1236 | mutex_init(&adap->userspace_clients_lock); |
6629dcff | 1237 | INIT_LIST_HEAD(&adap->userspace_clients); |
1da177e4 | 1238 | |
8fcfef6e JD |
1239 | /* Set default timeout to 1 second if not already set */ |
1240 | if (adap->timeout == 0) | |
1241 | adap->timeout = HZ; | |
1242 | ||
27d9c183 | 1243 | dev_set_name(&adap->dev, "i2c-%d", adap->nr); |
4f8cf824 JD |
1244 | adap->dev.bus = &i2c_bus_type; |
1245 | adap->dev.type = &i2c_adapter_type; | |
b119c6c9 JD |
1246 | res = device_register(&adap->dev); |
1247 | if (res) | |
1248 | goto out_list; | |
1da177e4 | 1249 | |
b6d7b3d1 JD |
1250 | dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name); |
1251 | ||
2bb5095a JD |
1252 | #ifdef CONFIG_I2C_COMPAT |
1253 | res = class_compat_create_link(i2c_adapter_compat_class, &adap->dev, | |
1254 | adap->dev.parent); | |
1255 | if (res) | |
1256 | dev_warn(&adap->dev, | |
1257 | "Failed to create compatibility class link\n"); | |
1258 | #endif | |
1259 | ||
5f9296ba VK |
1260 | /* bus recovery specific initialization */ |
1261 | if (adap->bus_recovery_info) { | |
1262 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
1263 | ||
1264 | if (!bri->recover_bus) { | |
1265 | dev_err(&adap->dev, "No recover_bus() found, not using recovery\n"); | |
1266 | adap->bus_recovery_info = NULL; | |
1267 | goto exit_recovery; | |
1268 | } | |
1269 | ||
1270 | /* Generic GPIO recovery */ | |
1271 | if (bri->recover_bus == i2c_generic_gpio_recovery) { | |
1272 | if (!gpio_is_valid(bri->scl_gpio)) { | |
1273 | dev_err(&adap->dev, "Invalid SCL gpio, not using recovery\n"); | |
1274 | adap->bus_recovery_info = NULL; | |
1275 | goto exit_recovery; | |
1276 | } | |
1277 | ||
1278 | if (gpio_is_valid(bri->sda_gpio)) | |
1279 | bri->get_sda = get_sda_gpio_value; | |
1280 | else | |
1281 | bri->get_sda = NULL; | |
1282 | ||
1283 | bri->get_scl = get_scl_gpio_value; | |
1284 | bri->set_scl = set_scl_gpio_value; | |
1285 | } else if (!bri->set_scl || !bri->get_scl) { | |
1286 | /* Generic SCL recovery */ | |
1287 | dev_err(&adap->dev, "No {get|set}_gpio() found, not using recovery\n"); | |
1288 | adap->bus_recovery_info = NULL; | |
1289 | } | |
1290 | } | |
1291 | ||
1292 | exit_recovery: | |
729d6dd5 | 1293 | /* create pre-declared device nodes */ |
687b81d0 | 1294 | of_i2c_register_devices(adap); |
55e71edb | 1295 | acpi_i2c_register_devices(adap); |
687b81d0 | 1296 | |
6e13e641 DB |
1297 | if (adap->nr < __i2c_first_dynamic_bus_num) |
1298 | i2c_scan_static_board_info(adap); | |
1299 | ||
4735c98f | 1300 | /* Notify drivers */ |
35fc37f8 | 1301 | mutex_lock(&core_lock); |
d6703281 | 1302 | bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter); |
caada32a | 1303 | mutex_unlock(&core_lock); |
35fc37f8 JD |
1304 | |
1305 | return 0; | |
b119c6c9 | 1306 | |
b119c6c9 | 1307 | out_list: |
35fc37f8 | 1308 | mutex_lock(&core_lock); |
b119c6c9 | 1309 | idr_remove(&i2c_adapter_idr, adap->nr); |
35fc37f8 JD |
1310 | mutex_unlock(&core_lock); |
1311 | return res; | |
1da177e4 LT |
1312 | } |
1313 | ||
ee5c2744 DA |
1314 | /** |
1315 | * __i2c_add_numbered_adapter - i2c_add_numbered_adapter where nr is never -1 | |
1316 | * @adap: the adapter to register (with adap->nr initialized) | |
1317 | * Context: can sleep | |
1318 | * | |
1319 | * See i2c_add_numbered_adapter() for details. | |
1320 | */ | |
1321 | static int __i2c_add_numbered_adapter(struct i2c_adapter *adap) | |
1322 | { | |
1323 | int id; | |
1324 | ||
1325 | mutex_lock(&core_lock); | |
1326 | id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1, | |
1327 | GFP_KERNEL); | |
1328 | mutex_unlock(&core_lock); | |
1329 | if (id < 0) | |
1330 | return id == -ENOSPC ? -EBUSY : id; | |
1331 | ||
1332 | return i2c_register_adapter(adap); | |
1333 | } | |
1334 | ||
6e13e641 DB |
1335 | /** |
1336 | * i2c_add_adapter - declare i2c adapter, use dynamic bus number | |
1337 | * @adapter: the adapter to add | |
d64f73be | 1338 | * Context: can sleep |
6e13e641 DB |
1339 | * |
1340 | * This routine is used to declare an I2C adapter when its bus number | |
ee5c2744 DA |
1341 | * doesn't matter or when its bus number is specified by an dt alias. |
1342 | * Examples of bases when the bus number doesn't matter: I2C adapters | |
1343 | * dynamically added by USB links or PCI plugin cards. | |
6e13e641 DB |
1344 | * |
1345 | * When this returns zero, a new bus number was allocated and stored | |
1346 | * in adap->nr, and the specified adapter became available for clients. | |
1347 | * Otherwise, a negative errno value is returned. | |
1348 | */ | |
1349 | int i2c_add_adapter(struct i2c_adapter *adapter) | |
1350 | { | |
ee5c2744 | 1351 | struct device *dev = &adapter->dev; |
4ae42b0f | 1352 | int id; |
6e13e641 | 1353 | |
ee5c2744 DA |
1354 | if (dev->of_node) { |
1355 | id = of_alias_get_id(dev->of_node, "i2c"); | |
1356 | if (id >= 0) { | |
1357 | adapter->nr = id; | |
1358 | return __i2c_add_numbered_adapter(adapter); | |
1359 | } | |
1360 | } | |
1361 | ||
caada32a | 1362 | mutex_lock(&core_lock); |
4ae42b0f TH |
1363 | id = idr_alloc(&i2c_adapter_idr, adapter, |
1364 | __i2c_first_dynamic_bus_num, 0, GFP_KERNEL); | |
caada32a | 1365 | mutex_unlock(&core_lock); |
4ae42b0f TH |
1366 | if (id < 0) |
1367 | return id; | |
6e13e641 DB |
1368 | |
1369 | adapter->nr = id; | |
4ae42b0f | 1370 | |
6e13e641 DB |
1371 | return i2c_register_adapter(adapter); |
1372 | } | |
1373 | EXPORT_SYMBOL(i2c_add_adapter); | |
1374 | ||
1375 | /** | |
1376 | * i2c_add_numbered_adapter - declare i2c adapter, use static bus number | |
1377 | * @adap: the adapter to register (with adap->nr initialized) | |
d64f73be | 1378 | * Context: can sleep |
6e13e641 DB |
1379 | * |
1380 | * This routine is used to declare an I2C adapter when its bus number | |
8c07e46f RD |
1381 | * matters. For example, use it for I2C adapters from system-on-chip CPUs, |
1382 | * or otherwise built in to the system's mainboard, and where i2c_board_info | |
6e13e641 DB |
1383 | * is used to properly configure I2C devices. |
1384 | * | |
488bf314 GL |
1385 | * If the requested bus number is set to -1, then this function will behave |
1386 | * identically to i2c_add_adapter, and will dynamically assign a bus number. | |
1387 | * | |
6e13e641 DB |
1388 | * If no devices have pre-been declared for this bus, then be sure to |
1389 | * register the adapter before any dynamically allocated ones. Otherwise | |
1390 | * the required bus ID may not be available. | |
1391 | * | |
1392 | * When this returns zero, the specified adapter became available for | |
1393 | * clients using the bus number provided in adap->nr. Also, the table | |
1394 | * of I2C devices pre-declared using i2c_register_board_info() is scanned, | |
1395 | * and the appropriate driver model device nodes are created. Otherwise, a | |
1396 | * negative errno value is returned. | |
1397 | */ | |
1398 | int i2c_add_numbered_adapter(struct i2c_adapter *adap) | |
1399 | { | |
488bf314 GL |
1400 | if (adap->nr == -1) /* -1 means dynamically assign bus id */ |
1401 | return i2c_add_adapter(adap); | |
6e13e641 | 1402 | |
ee5c2744 | 1403 | return __i2c_add_numbered_adapter(adap); |
6e13e641 DB |
1404 | } |
1405 | EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter); | |
1406 | ||
19baba4c | 1407 | static void i2c_do_del_adapter(struct i2c_driver *driver, |
69b0089a | 1408 | struct i2c_adapter *adapter) |
026526f5 | 1409 | { |
4735c98f | 1410 | struct i2c_client *client, *_n; |
026526f5 | 1411 | |
acec211c JD |
1412 | /* Remove the devices we created ourselves as the result of hardware |
1413 | * probing (using a driver's detect method) */ | |
4735c98f JD |
1414 | list_for_each_entry_safe(client, _n, &driver->clients, detected) { |
1415 | if (client->adapter == adapter) { | |
1416 | dev_dbg(&adapter->dev, "Removing %s at 0x%x\n", | |
1417 | client->name, client->addr); | |
1418 | list_del(&client->detected); | |
1419 | i2c_unregister_device(client); | |
1420 | } | |
1421 | } | |
026526f5 JD |
1422 | } |
1423 | ||
e549c2b5 | 1424 | static int __unregister_client(struct device *dev, void *dummy) |
5219bf88 JD |
1425 | { |
1426 | struct i2c_client *client = i2c_verify_client(dev); | |
1427 | if (client && strcmp(client->name, "dummy")) | |
1428 | i2c_unregister_device(client); | |
1429 | return 0; | |
1430 | } | |
1431 | ||
1432 | static int __unregister_dummy(struct device *dev, void *dummy) | |
e549c2b5 JD |
1433 | { |
1434 | struct i2c_client *client = i2c_verify_client(dev); | |
1435 | if (client) | |
1436 | i2c_unregister_device(client); | |
1437 | return 0; | |
1438 | } | |
1439 | ||
69b0089a JD |
1440 | static int __process_removed_adapter(struct device_driver *d, void *data) |
1441 | { | |
19baba4c LPC |
1442 | i2c_do_del_adapter(to_i2c_driver(d), data); |
1443 | return 0; | |
69b0089a JD |
1444 | } |
1445 | ||
d64f73be DB |
1446 | /** |
1447 | * i2c_del_adapter - unregister I2C adapter | |
1448 | * @adap: the adapter being unregistered | |
1449 | * Context: can sleep | |
1450 | * | |
1451 | * This unregisters an I2C adapter which was previously registered | |
1452 | * by @i2c_add_adapter or @i2c_add_numbered_adapter. | |
1453 | */ | |
71546300 | 1454 | void i2c_del_adapter(struct i2c_adapter *adap) |
1da177e4 | 1455 | { |
35fc37f8 | 1456 | struct i2c_adapter *found; |
bbd2d9c9 | 1457 | struct i2c_client *client, *next; |
1da177e4 LT |
1458 | |
1459 | /* First make sure that this adapter was ever added */ | |
35fc37f8 JD |
1460 | mutex_lock(&core_lock); |
1461 | found = idr_find(&i2c_adapter_idr, adap->nr); | |
1462 | mutex_unlock(&core_lock); | |
1463 | if (found != adap) { | |
b6d7b3d1 JD |
1464 | pr_debug("i2c-core: attempting to delete unregistered " |
1465 | "adapter [%s]\n", adap->name); | |
71546300 | 1466 | return; |
1da177e4 LT |
1467 | } |
1468 | ||
026526f5 | 1469 | /* Tell drivers about this removal */ |
35fc37f8 | 1470 | mutex_lock(&core_lock); |
19baba4c | 1471 | bus_for_each_drv(&i2c_bus_type, NULL, adap, |
69b0089a | 1472 | __process_removed_adapter); |
35fc37f8 | 1473 | mutex_unlock(&core_lock); |
1da177e4 | 1474 | |
bbd2d9c9 | 1475 | /* Remove devices instantiated from sysfs */ |
390946b1 JD |
1476 | mutex_lock_nested(&adap->userspace_clients_lock, |
1477 | i2c_adapter_depth(adap)); | |
6629dcff JD |
1478 | list_for_each_entry_safe(client, next, &adap->userspace_clients, |
1479 | detected) { | |
1480 | dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name, | |
1481 | client->addr); | |
1482 | list_del(&client->detected); | |
1483 | i2c_unregister_device(client); | |
bbd2d9c9 | 1484 | } |
dafc50d1 | 1485 | mutex_unlock(&adap->userspace_clients_lock); |
bbd2d9c9 | 1486 | |
e549c2b5 | 1487 | /* Detach any active clients. This can't fail, thus we do not |
5219bf88 JD |
1488 | * check the returned value. This is a two-pass process, because |
1489 | * we can't remove the dummy devices during the first pass: they | |
1490 | * could have been instantiated by real devices wishing to clean | |
1491 | * them up properly, so we give them a chance to do that first. */ | |
19baba4c LPC |
1492 | device_for_each_child(&adap->dev, NULL, __unregister_client); |
1493 | device_for_each_child(&adap->dev, NULL, __unregister_dummy); | |
1da177e4 | 1494 | |
2bb5095a JD |
1495 | #ifdef CONFIG_I2C_COMPAT |
1496 | class_compat_remove_link(i2c_adapter_compat_class, &adap->dev, | |
1497 | adap->dev.parent); | |
1498 | #endif | |
1499 | ||
c5567521 TLSC |
1500 | /* device name is gone after device_unregister */ |
1501 | dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name); | |
1502 | ||
1da177e4 LT |
1503 | /* clean up the sysfs representation */ |
1504 | init_completion(&adap->dev_released); | |
1da177e4 | 1505 | device_unregister(&adap->dev); |
1da177e4 LT |
1506 | |
1507 | /* wait for sysfs to drop all references */ | |
1508 | wait_for_completion(&adap->dev_released); | |
1da177e4 | 1509 | |
6e13e641 | 1510 | /* free bus id */ |
35fc37f8 | 1511 | mutex_lock(&core_lock); |
1da177e4 | 1512 | idr_remove(&i2c_adapter_idr, adap->nr); |
35fc37f8 | 1513 | mutex_unlock(&core_lock); |
1da177e4 | 1514 | |
bd4bc3db JD |
1515 | /* Clear the device structure in case this adapter is ever going to be |
1516 | added again */ | |
1517 | memset(&adap->dev, 0, sizeof(adap->dev)); | |
1da177e4 | 1518 | } |
c0564606 | 1519 | EXPORT_SYMBOL(i2c_del_adapter); |
1da177e4 | 1520 | |
7b4fbc50 DB |
1521 | /* ------------------------------------------------------------------------- */ |
1522 | ||
7ae31482 JD |
1523 | int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *)) |
1524 | { | |
1525 | int res; | |
1526 | ||
1527 | mutex_lock(&core_lock); | |
1528 | res = bus_for_each_dev(&i2c_bus_type, NULL, data, fn); | |
1529 | mutex_unlock(&core_lock); | |
1530 | ||
1531 | return res; | |
1532 | } | |
1533 | EXPORT_SYMBOL_GPL(i2c_for_each_dev); | |
1534 | ||
69b0089a | 1535 | static int __process_new_driver(struct device *dev, void *data) |
7f101a97 | 1536 | { |
4f8cf824 JD |
1537 | if (dev->type != &i2c_adapter_type) |
1538 | return 0; | |
69b0089a | 1539 | return i2c_do_add_adapter(data, to_i2c_adapter(dev)); |
7f101a97 DY |
1540 | } |
1541 | ||
7b4fbc50 DB |
1542 | /* |
1543 | * An i2c_driver is used with one or more i2c_client (device) nodes to access | |
729d6dd5 | 1544 | * i2c slave chips, on a bus instance associated with some i2c_adapter. |
1da177e4 LT |
1545 | */ |
1546 | ||
de59cf9e | 1547 | int i2c_register_driver(struct module *owner, struct i2c_driver *driver) |
1da177e4 | 1548 | { |
7eebcb7c | 1549 | int res; |
1da177e4 | 1550 | |
1d0b19c9 DB |
1551 | /* Can't register until after driver model init */ |
1552 | if (unlikely(WARN_ON(!i2c_bus_type.p))) | |
1553 | return -EAGAIN; | |
1554 | ||
1da177e4 | 1555 | /* add the driver to the list of i2c drivers in the driver core */ |
de59cf9e | 1556 | driver->driver.owner = owner; |
1da177e4 | 1557 | driver->driver.bus = &i2c_bus_type; |
1da177e4 | 1558 | |
729d6dd5 | 1559 | /* When registration returns, the driver core |
6e13e641 DB |
1560 | * will have called probe() for all matching-but-unbound devices. |
1561 | */ | |
1da177e4 LT |
1562 | res = driver_register(&driver->driver); |
1563 | if (res) | |
7eebcb7c | 1564 | return res; |
438d6c2c | 1565 | |
f4e8db31 MB |
1566 | /* Drivers should switch to dev_pm_ops instead. */ |
1567 | if (driver->suspend) | |
1568 | pr_warn("i2c-core: driver [%s] using legacy suspend method\n", | |
1569 | driver->driver.name); | |
1570 | if (driver->resume) | |
1571 | pr_warn("i2c-core: driver [%s] using legacy resume method\n", | |
1572 | driver->driver.name); | |
1573 | ||
35d8b2e6 | 1574 | pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name); |
1da177e4 | 1575 | |
4735c98f JD |
1576 | INIT_LIST_HEAD(&driver->clients); |
1577 | /* Walk the adapters that are already present */ | |
7ae31482 | 1578 | i2c_for_each_dev(driver, __process_new_driver); |
35fc37f8 | 1579 | |
7f101a97 DY |
1580 | return 0; |
1581 | } | |
1582 | EXPORT_SYMBOL(i2c_register_driver); | |
1583 | ||
69b0089a | 1584 | static int __process_removed_driver(struct device *dev, void *data) |
7f101a97 | 1585 | { |
19baba4c LPC |
1586 | if (dev->type == &i2c_adapter_type) |
1587 | i2c_do_del_adapter(data, to_i2c_adapter(dev)); | |
1588 | return 0; | |
1da177e4 LT |
1589 | } |
1590 | ||
a1d9e6e4 DB |
1591 | /** |
1592 | * i2c_del_driver - unregister I2C driver | |
1593 | * @driver: the driver being unregistered | |
d64f73be | 1594 | * Context: can sleep |
a1d9e6e4 | 1595 | */ |
b3e82096 | 1596 | void i2c_del_driver(struct i2c_driver *driver) |
1da177e4 | 1597 | { |
7ae31482 | 1598 | i2c_for_each_dev(driver, __process_removed_driver); |
1da177e4 LT |
1599 | |
1600 | driver_unregister(&driver->driver); | |
35d8b2e6 | 1601 | pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name); |
1da177e4 | 1602 | } |
c0564606 | 1603 | EXPORT_SYMBOL(i2c_del_driver); |
1da177e4 | 1604 | |
7b4fbc50 DB |
1605 | /* ------------------------------------------------------------------------- */ |
1606 | ||
e48d3319 JD |
1607 | /** |
1608 | * i2c_use_client - increments the reference count of the i2c client structure | |
1609 | * @client: the client being referenced | |
1610 | * | |
1611 | * Each live reference to a client should be refcounted. The driver model does | |
1612 | * that automatically as part of driver binding, so that most drivers don't | |
1613 | * need to do this explicitly: they hold a reference until they're unbound | |
1614 | * from the device. | |
1615 | * | |
1616 | * A pointer to the client with the incremented reference counter is returned. | |
1617 | */ | |
1618 | struct i2c_client *i2c_use_client(struct i2c_client *client) | |
1da177e4 | 1619 | { |
6ea438ec DB |
1620 | if (client && get_device(&client->dev)) |
1621 | return client; | |
1622 | return NULL; | |
1da177e4 | 1623 | } |
c0564606 | 1624 | EXPORT_SYMBOL(i2c_use_client); |
1da177e4 | 1625 | |
e48d3319 JD |
1626 | /** |
1627 | * i2c_release_client - release a use of the i2c client structure | |
1628 | * @client: the client being no longer referenced | |
1629 | * | |
1630 | * Must be called when a user of a client is finished with it. | |
1631 | */ | |
1632 | void i2c_release_client(struct i2c_client *client) | |
1da177e4 | 1633 | { |
6ea438ec DB |
1634 | if (client) |
1635 | put_device(&client->dev); | |
1da177e4 | 1636 | } |
c0564606 | 1637 | EXPORT_SYMBOL(i2c_release_client); |
1da177e4 | 1638 | |
9b766b81 DB |
1639 | struct i2c_cmd_arg { |
1640 | unsigned cmd; | |
1641 | void *arg; | |
1642 | }; | |
1643 | ||
1644 | static int i2c_cmd(struct device *dev, void *_arg) | |
1645 | { | |
1646 | struct i2c_client *client = i2c_verify_client(dev); | |
1647 | struct i2c_cmd_arg *arg = _arg; | |
0acc2b32 LPC |
1648 | struct i2c_driver *driver; |
1649 | ||
1650 | if (!client || !client->dev.driver) | |
1651 | return 0; | |
9b766b81 | 1652 | |
0acc2b32 LPC |
1653 | driver = to_i2c_driver(client->dev.driver); |
1654 | if (driver->command) | |
1655 | driver->command(client, arg->cmd, arg->arg); | |
9b766b81 DB |
1656 | return 0; |
1657 | } | |
1658 | ||
1da177e4 LT |
1659 | void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg) |
1660 | { | |
9b766b81 | 1661 | struct i2c_cmd_arg cmd_arg; |
1da177e4 | 1662 | |
9b766b81 DB |
1663 | cmd_arg.cmd = cmd; |
1664 | cmd_arg.arg = arg; | |
1665 | device_for_each_child(&adap->dev, &cmd_arg, i2c_cmd); | |
1da177e4 | 1666 | } |
c0564606 | 1667 | EXPORT_SYMBOL(i2c_clients_command); |
1da177e4 LT |
1668 | |
1669 | static int __init i2c_init(void) | |
1670 | { | |
1671 | int retval; | |
1672 | ||
1673 | retval = bus_register(&i2c_bus_type); | |
1da177e4 LT |
1674 | if (retval) |
1675 | return retval; | |
2bb5095a JD |
1676 | #ifdef CONFIG_I2C_COMPAT |
1677 | i2c_adapter_compat_class = class_compat_register("i2c-adapter"); | |
1678 | if (!i2c_adapter_compat_class) { | |
1679 | retval = -ENOMEM; | |
1680 | goto bus_err; | |
1681 | } | |
1682 | #endif | |
e9f1373b DB |
1683 | retval = i2c_add_driver(&dummy_driver); |
1684 | if (retval) | |
2bb5095a | 1685 | goto class_err; |
e9f1373b DB |
1686 | return 0; |
1687 | ||
2bb5095a JD |
1688 | class_err: |
1689 | #ifdef CONFIG_I2C_COMPAT | |
1690 | class_compat_unregister(i2c_adapter_compat_class); | |
e9f1373b | 1691 | bus_err: |
2bb5095a | 1692 | #endif |
e9f1373b DB |
1693 | bus_unregister(&i2c_bus_type); |
1694 | return retval; | |
1da177e4 LT |
1695 | } |
1696 | ||
1697 | static void __exit i2c_exit(void) | |
1698 | { | |
e9f1373b | 1699 | i2c_del_driver(&dummy_driver); |
2bb5095a JD |
1700 | #ifdef CONFIG_I2C_COMPAT |
1701 | class_compat_unregister(i2c_adapter_compat_class); | |
1702 | #endif | |
1da177e4 | 1703 | bus_unregister(&i2c_bus_type); |
d9a83d62 | 1704 | tracepoint_synchronize_unregister(); |
1da177e4 LT |
1705 | } |
1706 | ||
a10f9e7c DB |
1707 | /* We must initialize early, because some subsystems register i2c drivers |
1708 | * in subsys_initcall() code, but are linked (and initialized) before i2c. | |
1709 | */ | |
1710 | postcore_initcall(i2c_init); | |
1da177e4 LT |
1711 | module_exit(i2c_exit); |
1712 | ||
1713 | /* ---------------------------------------------------- | |
1714 | * the functional interface to the i2c busses. | |
1715 | * ---------------------------------------------------- | |
1716 | */ | |
1717 | ||
b37d2a3a JD |
1718 | /** |
1719 | * __i2c_transfer - unlocked flavor of i2c_transfer | |
1720 | * @adap: Handle to I2C bus | |
1721 | * @msgs: One or more messages to execute before STOP is issued to | |
1722 | * terminate the operation; each message begins with a START. | |
1723 | * @num: Number of messages to be executed. | |
1724 | * | |
1725 | * Returns negative errno, else the number of messages executed. | |
1726 | * | |
1727 | * Adapter lock must be held when calling this function. No debug logging | |
1728 | * takes place. adap->algo->master_xfer existence isn't checked. | |
1729 | */ | |
1730 | int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) | |
1731 | { | |
1732 | unsigned long orig_jiffies; | |
1733 | int ret, try; | |
1734 | ||
d9a83d62 DH |
1735 | /* i2c_trace_msg gets enabled when tracepoint i2c_transfer gets |
1736 | * enabled. This is an efficient way of keeping the for-loop from | |
1737 | * being executed when not needed. | |
1738 | */ | |
1739 | if (static_key_false(&i2c_trace_msg)) { | |
1740 | int i; | |
1741 | for (i = 0; i < num; i++) | |
1742 | if (msgs[i].flags & I2C_M_RD) | |
1743 | trace_i2c_read(adap, &msgs[i], i); | |
1744 | else | |
1745 | trace_i2c_write(adap, &msgs[i], i); | |
1746 | } | |
1747 | ||
b37d2a3a JD |
1748 | /* Retry automatically on arbitration loss */ |
1749 | orig_jiffies = jiffies; | |
1750 | for (ret = 0, try = 0; try <= adap->retries; try++) { | |
1751 | ret = adap->algo->master_xfer(adap, msgs, num); | |
1752 | if (ret != -EAGAIN) | |
1753 | break; | |
1754 | if (time_after(jiffies, orig_jiffies + adap->timeout)) | |
1755 | break; | |
1756 | } | |
1757 | ||
d9a83d62 DH |
1758 | if (static_key_false(&i2c_trace_msg)) { |
1759 | int i; | |
1760 | for (i = 0; i < ret; i++) | |
1761 | if (msgs[i].flags & I2C_M_RD) | |
1762 | trace_i2c_reply(adap, &msgs[i], i); | |
1763 | trace_i2c_result(adap, i, ret); | |
1764 | } | |
1765 | ||
b37d2a3a JD |
1766 | return ret; |
1767 | } | |
1768 | EXPORT_SYMBOL(__i2c_transfer); | |
1769 | ||
a1cdedac DB |
1770 | /** |
1771 | * i2c_transfer - execute a single or combined I2C message | |
1772 | * @adap: Handle to I2C bus | |
1773 | * @msgs: One or more messages to execute before STOP is issued to | |
1774 | * terminate the operation; each message begins with a START. | |
1775 | * @num: Number of messages to be executed. | |
1776 | * | |
1777 | * Returns negative errno, else the number of messages executed. | |
1778 | * | |
1779 | * Note that there is no requirement that each message be sent to | |
1780 | * the same slave address, although that is the most common model. | |
1781 | */ | |
09b8ce0a | 1782 | int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) |
1da177e4 | 1783 | { |
b37d2a3a | 1784 | int ret; |
1da177e4 | 1785 | |
a1cdedac DB |
1786 | /* REVISIT the fault reporting model here is weak: |
1787 | * | |
1788 | * - When we get an error after receiving N bytes from a slave, | |
1789 | * there is no way to report "N". | |
1790 | * | |
1791 | * - When we get a NAK after transmitting N bytes to a slave, | |
1792 | * there is no way to report "N" ... or to let the master | |
1793 | * continue executing the rest of this combined message, if | |
1794 | * that's the appropriate response. | |
1795 | * | |
1796 | * - When for example "num" is two and we successfully complete | |
1797 | * the first message but get an error part way through the | |
1798 | * second, it's unclear whether that should be reported as | |
1799 | * one (discarding status on the second message) or errno | |
1800 | * (discarding status on the first one). | |
1801 | */ | |
1802 | ||
1da177e4 LT |
1803 | if (adap->algo->master_xfer) { |
1804 | #ifdef DEBUG | |
1805 | for (ret = 0; ret < num; ret++) { | |
1806 | dev_dbg(&adap->dev, "master_xfer[%d] %c, addr=0x%02x, " | |
209d27c3 JD |
1807 | "len=%d%s\n", ret, (msgs[ret].flags & I2C_M_RD) |
1808 | ? 'R' : 'W', msgs[ret].addr, msgs[ret].len, | |
1809 | (msgs[ret].flags & I2C_M_RECV_LEN) ? "+" : ""); | |
1da177e4 LT |
1810 | } |
1811 | #endif | |
1812 | ||
cea443a8 | 1813 | if (in_atomic() || irqs_disabled()) { |
fe61e07e | 1814 | ret = i2c_trylock_adapter(adap); |
cea443a8 MR |
1815 | if (!ret) |
1816 | /* I2C activity is ongoing. */ | |
1817 | return -EAGAIN; | |
1818 | } else { | |
fe61e07e | 1819 | i2c_lock_adapter(adap); |
cea443a8 MR |
1820 | } |
1821 | ||
b37d2a3a | 1822 | ret = __i2c_transfer(adap, msgs, num); |
fe61e07e | 1823 | i2c_unlock_adapter(adap); |
1da177e4 LT |
1824 | |
1825 | return ret; | |
1826 | } else { | |
1827 | dev_dbg(&adap->dev, "I2C level transfers not supported\n"); | |
24a5bb7b | 1828 | return -EOPNOTSUPP; |
1da177e4 LT |
1829 | } |
1830 | } | |
c0564606 | 1831 | EXPORT_SYMBOL(i2c_transfer); |
1da177e4 | 1832 | |
a1cdedac DB |
1833 | /** |
1834 | * i2c_master_send - issue a single I2C message in master transmit mode | |
1835 | * @client: Handle to slave device | |
1836 | * @buf: Data that will be written to the slave | |
0c43ea54 | 1837 | * @count: How many bytes to write, must be less than 64k since msg.len is u16 |
a1cdedac DB |
1838 | * |
1839 | * Returns negative errno, or else the number of bytes written. | |
1840 | */ | |
0cc43a18 | 1841 | int i2c_master_send(const struct i2c_client *client, const char *buf, int count) |
1da177e4 LT |
1842 | { |
1843 | int ret; | |
7225acf4 | 1844 | struct i2c_adapter *adap = client->adapter; |
1da177e4 LT |
1845 | struct i2c_msg msg; |
1846 | ||
815f55f2 JD |
1847 | msg.addr = client->addr; |
1848 | msg.flags = client->flags & I2C_M_TEN; | |
1849 | msg.len = count; | |
1850 | msg.buf = (char *)buf; | |
438d6c2c | 1851 | |
815f55f2 | 1852 | ret = i2c_transfer(adap, &msg, 1); |
1da177e4 | 1853 | |
834aa6f3 WS |
1854 | /* |
1855 | * If everything went ok (i.e. 1 msg transmitted), return #bytes | |
1856 | * transmitted, else error code. | |
1857 | */ | |
815f55f2 | 1858 | return (ret == 1) ? count : ret; |
1da177e4 | 1859 | } |
c0564606 | 1860 | EXPORT_SYMBOL(i2c_master_send); |
1da177e4 | 1861 | |
a1cdedac DB |
1862 | /** |
1863 | * i2c_master_recv - issue a single I2C message in master receive mode | |
1864 | * @client: Handle to slave device | |
1865 | * @buf: Where to store data read from slave | |
0c43ea54 | 1866 | * @count: How many bytes to read, must be less than 64k since msg.len is u16 |
a1cdedac DB |
1867 | * |
1868 | * Returns negative errno, or else the number of bytes read. | |
1869 | */ | |
0cc43a18 | 1870 | int i2c_master_recv(const struct i2c_client *client, char *buf, int count) |
1da177e4 | 1871 | { |
7225acf4 | 1872 | struct i2c_adapter *adap = client->adapter; |
1da177e4 LT |
1873 | struct i2c_msg msg; |
1874 | int ret; | |
815f55f2 JD |
1875 | |
1876 | msg.addr = client->addr; | |
1877 | msg.flags = client->flags & I2C_M_TEN; | |
1878 | msg.flags |= I2C_M_RD; | |
1879 | msg.len = count; | |
1880 | msg.buf = buf; | |
1881 | ||
1882 | ret = i2c_transfer(adap, &msg, 1); | |
1883 | ||
834aa6f3 WS |
1884 | /* |
1885 | * If everything went ok (i.e. 1 msg received), return #bytes received, | |
1886 | * else error code. | |
1887 | */ | |
815f55f2 | 1888 | return (ret == 1) ? count : ret; |
1da177e4 | 1889 | } |
c0564606 | 1890 | EXPORT_SYMBOL(i2c_master_recv); |
1da177e4 | 1891 | |
1da177e4 LT |
1892 | /* ---------------------------------------------------- |
1893 | * the i2c address scanning function | |
1894 | * Will not work for 10-bit addresses! | |
1895 | * ---------------------------------------------------- | |
1896 | */ | |
1da177e4 | 1897 | |
63e4e802 JD |
1898 | /* |
1899 | * Legacy default probe function, mostly relevant for SMBus. The default | |
1900 | * probe method is a quick write, but it is known to corrupt the 24RF08 | |
1901 | * EEPROMs due to a state machine bug, and could also irreversibly | |
1902 | * write-protect some EEPROMs, so for address ranges 0x30-0x37 and 0x50-0x5f, | |
1903 | * we use a short byte read instead. Also, some bus drivers don't implement | |
1904 | * quick write, so we fallback to a byte read in that case too. | |
1905 | * On x86, there is another special case for FSC hardware monitoring chips, | |
1906 | * which want regular byte reads (address 0x73.) Fortunately, these are the | |
1907 | * only known chips using this I2C address on PC hardware. | |
1908 | * Returns 1 if probe succeeded, 0 if not. | |
1909 | */ | |
1910 | static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr) | |
1911 | { | |
1912 | int err; | |
1913 | union i2c_smbus_data dummy; | |
1914 | ||
1915 | #ifdef CONFIG_X86 | |
1916 | if (addr == 0x73 && (adap->class & I2C_CLASS_HWMON) | |
1917 | && i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE_DATA)) | |
1918 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
1919 | I2C_SMBUS_BYTE_DATA, &dummy); | |
1920 | else | |
1921 | #endif | |
8031d79b JD |
1922 | if (!((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50) |
1923 | && i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) | |
63e4e802 JD |
1924 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0, |
1925 | I2C_SMBUS_QUICK, NULL); | |
8031d79b JD |
1926 | else if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) |
1927 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
1928 | I2C_SMBUS_BYTE, &dummy); | |
1929 | else { | |
d63a9e85 AL |
1930 | dev_warn(&adap->dev, "No suitable probing method supported for address 0x%02X\n", |
1931 | addr); | |
8031d79b JD |
1932 | err = -EOPNOTSUPP; |
1933 | } | |
63e4e802 JD |
1934 | |
1935 | return err >= 0; | |
1936 | } | |
1937 | ||
ccfbbd08 | 1938 | static int i2c_detect_address(struct i2c_client *temp_client, |
4735c98f JD |
1939 | struct i2c_driver *driver) |
1940 | { | |
1941 | struct i2c_board_info info; | |
1942 | struct i2c_adapter *adapter = temp_client->adapter; | |
1943 | int addr = temp_client->addr; | |
1944 | int err; | |
1945 | ||
1946 | /* Make sure the address is valid */ | |
656b8761 JD |
1947 | err = i2c_check_addr_validity(addr); |
1948 | if (err) { | |
4735c98f JD |
1949 | dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n", |
1950 | addr); | |
656b8761 | 1951 | return err; |
4735c98f JD |
1952 | } |
1953 | ||
1954 | /* Skip if already in use */ | |
3b5f794b | 1955 | if (i2c_check_addr_busy(adapter, addr)) |
4735c98f JD |
1956 | return 0; |
1957 | ||
ccfbbd08 | 1958 | /* Make sure there is something at this address */ |
63e4e802 JD |
1959 | if (!i2c_default_probe(adapter, addr)) |
1960 | return 0; | |
4735c98f JD |
1961 | |
1962 | /* Finally call the custom detection function */ | |
1963 | memset(&info, 0, sizeof(struct i2c_board_info)); | |
1964 | info.addr = addr; | |
310ec792 | 1965 | err = driver->detect(temp_client, &info); |
4735c98f JD |
1966 | if (err) { |
1967 | /* -ENODEV is returned if the detection fails. We catch it | |
1968 | here as this isn't an error. */ | |
1969 | return err == -ENODEV ? 0 : err; | |
1970 | } | |
1971 | ||
1972 | /* Consistency check */ | |
1973 | if (info.type[0] == '\0') { | |
1974 | dev_err(&adapter->dev, "%s detection function provided " | |
1975 | "no name for 0x%x\n", driver->driver.name, | |
1976 | addr); | |
1977 | } else { | |
1978 | struct i2c_client *client; | |
1979 | ||
1980 | /* Detection succeeded, instantiate the device */ | |
0c176170 WS |
1981 | if (adapter->class & I2C_CLASS_DEPRECATED) |
1982 | dev_warn(&adapter->dev, | |
1983 | "This adapter will soon drop class based instantiation of devices. " | |
1984 | "Please make sure client 0x%02x gets instantiated by other means. " | |
1985 | "Check 'Documentation/i2c/instantiating-devices' for details.\n", | |
1986 | info.addr); | |
1987 | ||
4735c98f JD |
1988 | dev_dbg(&adapter->dev, "Creating %s at 0x%02x\n", |
1989 | info.type, info.addr); | |
1990 | client = i2c_new_device(adapter, &info); | |
1991 | if (client) | |
1992 | list_add_tail(&client->detected, &driver->clients); | |
1993 | else | |
1994 | dev_err(&adapter->dev, "Failed creating %s at 0x%02x\n", | |
1995 | info.type, info.addr); | |
1996 | } | |
1997 | return 0; | |
1998 | } | |
1999 | ||
2000 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver) | |
2001 | { | |
c3813d6a | 2002 | const unsigned short *address_list; |
4735c98f JD |
2003 | struct i2c_client *temp_client; |
2004 | int i, err = 0; | |
2005 | int adap_id = i2c_adapter_id(adapter); | |
2006 | ||
c3813d6a JD |
2007 | address_list = driver->address_list; |
2008 | if (!driver->detect || !address_list) | |
4735c98f JD |
2009 | return 0; |
2010 | ||
51b54ba9 JD |
2011 | /* Stop here if the classes do not match */ |
2012 | if (!(adapter->class & driver->class)) | |
2013 | return 0; | |
2014 | ||
4735c98f JD |
2015 | /* Set up a temporary client to help detect callback */ |
2016 | temp_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL); | |
2017 | if (!temp_client) | |
2018 | return -ENOMEM; | |
2019 | temp_client->adapter = adapter; | |
2020 | ||
c3813d6a | 2021 | for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) { |
4735c98f | 2022 | dev_dbg(&adapter->dev, "found normal entry for adapter %d, " |
c3813d6a JD |
2023 | "addr 0x%02x\n", adap_id, address_list[i]); |
2024 | temp_client->addr = address_list[i]; | |
ccfbbd08 | 2025 | err = i2c_detect_address(temp_client, driver); |
51b54ba9 JD |
2026 | if (unlikely(err)) |
2027 | break; | |
4735c98f JD |
2028 | } |
2029 | ||
4735c98f JD |
2030 | kfree(temp_client); |
2031 | return err; | |
2032 | } | |
2033 | ||
d44f19d5 JD |
2034 | int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr) |
2035 | { | |
2036 | return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
2037 | I2C_SMBUS_QUICK, NULL) >= 0; | |
2038 | } | |
2039 | EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read); | |
2040 | ||
12b5053a JD |
2041 | struct i2c_client * |
2042 | i2c_new_probed_device(struct i2c_adapter *adap, | |
2043 | struct i2c_board_info *info, | |
9a94241a JD |
2044 | unsigned short const *addr_list, |
2045 | int (*probe)(struct i2c_adapter *, unsigned short addr)) | |
12b5053a JD |
2046 | { |
2047 | int i; | |
2048 | ||
8031d79b | 2049 | if (!probe) |
9a94241a | 2050 | probe = i2c_default_probe; |
12b5053a | 2051 | |
12b5053a JD |
2052 | for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { |
2053 | /* Check address validity */ | |
656b8761 | 2054 | if (i2c_check_addr_validity(addr_list[i]) < 0) { |
12b5053a JD |
2055 | dev_warn(&adap->dev, "Invalid 7-bit address " |
2056 | "0x%02x\n", addr_list[i]); | |
2057 | continue; | |
2058 | } | |
2059 | ||
2060 | /* Check address availability */ | |
3b5f794b | 2061 | if (i2c_check_addr_busy(adap, addr_list[i])) { |
12b5053a JD |
2062 | dev_dbg(&adap->dev, "Address 0x%02x already in " |
2063 | "use, not probing\n", addr_list[i]); | |
2064 | continue; | |
2065 | } | |
2066 | ||
63e4e802 | 2067 | /* Test address responsiveness */ |
9a94241a | 2068 | if (probe(adap, addr_list[i])) |
63e4e802 | 2069 | break; |
12b5053a | 2070 | } |
12b5053a JD |
2071 | |
2072 | if (addr_list[i] == I2C_CLIENT_END) { | |
2073 | dev_dbg(&adap->dev, "Probing failed, no device found\n"); | |
2074 | return NULL; | |
2075 | } | |
2076 | ||
2077 | info->addr = addr_list[i]; | |
2078 | return i2c_new_device(adap, info); | |
2079 | } | |
2080 | EXPORT_SYMBOL_GPL(i2c_new_probed_device); | |
2081 | ||
d735b34d | 2082 | struct i2c_adapter *i2c_get_adapter(int nr) |
1da177e4 | 2083 | { |
1da177e4 | 2084 | struct i2c_adapter *adapter; |
438d6c2c | 2085 | |
caada32a | 2086 | mutex_lock(&core_lock); |
d735b34d | 2087 | adapter = idr_find(&i2c_adapter_idr, nr); |
a0920e10 MH |
2088 | if (adapter && !try_module_get(adapter->owner)) |
2089 | adapter = NULL; | |
2090 | ||
caada32a | 2091 | mutex_unlock(&core_lock); |
a0920e10 | 2092 | return adapter; |
1da177e4 | 2093 | } |
c0564606 | 2094 | EXPORT_SYMBOL(i2c_get_adapter); |
1da177e4 LT |
2095 | |
2096 | void i2c_put_adapter(struct i2c_adapter *adap) | |
2097 | { | |
c66c4cc0 SH |
2098 | if (adap) |
2099 | module_put(adap->owner); | |
1da177e4 | 2100 | } |
c0564606 | 2101 | EXPORT_SYMBOL(i2c_put_adapter); |
1da177e4 LT |
2102 | |
2103 | /* The SMBus parts */ | |
2104 | ||
438d6c2c | 2105 | #define POLY (0x1070U << 3) |
09b8ce0a | 2106 | static u8 crc8(u16 data) |
1da177e4 LT |
2107 | { |
2108 | int i; | |
438d6c2c | 2109 | |
7225acf4 | 2110 | for (i = 0; i < 8; i++) { |
438d6c2c | 2111 | if (data & 0x8000) |
1da177e4 LT |
2112 | data = data ^ POLY; |
2113 | data = data << 1; | |
2114 | } | |
2115 | return (u8)(data >> 8); | |
2116 | } | |
2117 | ||
421ef47b JD |
2118 | /* Incremental CRC8 over count bytes in the array pointed to by p */ |
2119 | static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count) | |
1da177e4 LT |
2120 | { |
2121 | int i; | |
2122 | ||
7225acf4 | 2123 | for (i = 0; i < count; i++) |
421ef47b | 2124 | crc = crc8((crc ^ p[i]) << 8); |
1da177e4 LT |
2125 | return crc; |
2126 | } | |
2127 | ||
421ef47b JD |
2128 | /* Assume a 7-bit address, which is reasonable for SMBus */ |
2129 | static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg) | |
1da177e4 | 2130 | { |
421ef47b JD |
2131 | /* The address will be sent first */ |
2132 | u8 addr = (msg->addr << 1) | !!(msg->flags & I2C_M_RD); | |
2133 | pec = i2c_smbus_pec(pec, &addr, 1); | |
2134 | ||
2135 | /* The data buffer follows */ | |
2136 | return i2c_smbus_pec(pec, msg->buf, msg->len); | |
1da177e4 LT |
2137 | } |
2138 | ||
421ef47b JD |
2139 | /* Used for write only transactions */ |
2140 | static inline void i2c_smbus_add_pec(struct i2c_msg *msg) | |
1da177e4 | 2141 | { |
421ef47b JD |
2142 | msg->buf[msg->len] = i2c_smbus_msg_pec(0, msg); |
2143 | msg->len++; | |
1da177e4 LT |
2144 | } |
2145 | ||
421ef47b JD |
2146 | /* Return <0 on CRC error |
2147 | If there was a write before this read (most cases) we need to take the | |
2148 | partial CRC from the write part into account. | |
2149 | Note that this function does modify the message (we need to decrease the | |
2150 | message length to hide the CRC byte from the caller). */ | |
2151 | static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg) | |
1da177e4 | 2152 | { |
421ef47b JD |
2153 | u8 rpec = msg->buf[--msg->len]; |
2154 | cpec = i2c_smbus_msg_pec(cpec, msg); | |
1da177e4 | 2155 | |
1da177e4 LT |
2156 | if (rpec != cpec) { |
2157 | pr_debug("i2c-core: Bad PEC 0x%02x vs. 0x%02x\n", | |
2158 | rpec, cpec); | |
24a5bb7b | 2159 | return -EBADMSG; |
1da177e4 | 2160 | } |
438d6c2c | 2161 | return 0; |
1da177e4 LT |
2162 | } |
2163 | ||
a1cdedac DB |
2164 | /** |
2165 | * i2c_smbus_read_byte - SMBus "receive byte" protocol | |
2166 | * @client: Handle to slave device | |
2167 | * | |
2168 | * This executes the SMBus "receive byte" protocol, returning negative errno | |
2169 | * else the byte received from the device. | |
2170 | */ | |
0cc43a18 | 2171 | s32 i2c_smbus_read_byte(const struct i2c_client *client) |
1da177e4 LT |
2172 | { |
2173 | union i2c_smbus_data data; | |
24a5bb7b DB |
2174 | int status; |
2175 | ||
2176 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
2177 | I2C_SMBUS_READ, 0, | |
2178 | I2C_SMBUS_BYTE, &data); | |
2179 | return (status < 0) ? status : data.byte; | |
1da177e4 | 2180 | } |
c0564606 | 2181 | EXPORT_SYMBOL(i2c_smbus_read_byte); |
1da177e4 | 2182 | |
a1cdedac DB |
2183 | /** |
2184 | * i2c_smbus_write_byte - SMBus "send byte" protocol | |
2185 | * @client: Handle to slave device | |
2186 | * @value: Byte to be sent | |
2187 | * | |
2188 | * This executes the SMBus "send byte" protocol, returning negative errno | |
2189 | * else zero on success. | |
2190 | */ | |
0cc43a18 | 2191 | s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value) |
1da177e4 | 2192 | { |
7225acf4 | 2193 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
421ef47b | 2194 | I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL); |
1da177e4 | 2195 | } |
c0564606 | 2196 | EXPORT_SYMBOL(i2c_smbus_write_byte); |
1da177e4 | 2197 | |
a1cdedac DB |
2198 | /** |
2199 | * i2c_smbus_read_byte_data - SMBus "read byte" protocol | |
2200 | * @client: Handle to slave device | |
2201 | * @command: Byte interpreted by slave | |
2202 | * | |
2203 | * This executes the SMBus "read byte" protocol, returning negative errno | |
2204 | * else a data byte received from the device. | |
2205 | */ | |
0cc43a18 | 2206 | s32 i2c_smbus_read_byte_data(const struct i2c_client *client, u8 command) |
1da177e4 LT |
2207 | { |
2208 | union i2c_smbus_data data; | |
24a5bb7b DB |
2209 | int status; |
2210 | ||
2211 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
2212 | I2C_SMBUS_READ, command, | |
2213 | I2C_SMBUS_BYTE_DATA, &data); | |
2214 | return (status < 0) ? status : data.byte; | |
1da177e4 | 2215 | } |
c0564606 | 2216 | EXPORT_SYMBOL(i2c_smbus_read_byte_data); |
1da177e4 | 2217 | |
a1cdedac DB |
2218 | /** |
2219 | * i2c_smbus_write_byte_data - SMBus "write byte" protocol | |
2220 | * @client: Handle to slave device | |
2221 | * @command: Byte interpreted by slave | |
2222 | * @value: Byte being written | |
2223 | * | |
2224 | * This executes the SMBus "write byte" protocol, returning negative errno | |
2225 | * else zero on success. | |
2226 | */ | |
0cc43a18 JD |
2227 | s32 i2c_smbus_write_byte_data(const struct i2c_client *client, u8 command, |
2228 | u8 value) | |
1da177e4 LT |
2229 | { |
2230 | union i2c_smbus_data data; | |
2231 | data.byte = value; | |
7225acf4 FH |
2232 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2233 | I2C_SMBUS_WRITE, command, | |
2234 | I2C_SMBUS_BYTE_DATA, &data); | |
1da177e4 | 2235 | } |
c0564606 | 2236 | EXPORT_SYMBOL(i2c_smbus_write_byte_data); |
1da177e4 | 2237 | |
a1cdedac DB |
2238 | /** |
2239 | * i2c_smbus_read_word_data - SMBus "read word" protocol | |
2240 | * @client: Handle to slave device | |
2241 | * @command: Byte interpreted by slave | |
2242 | * | |
2243 | * This executes the SMBus "read word" protocol, returning negative errno | |
2244 | * else a 16-bit unsigned "word" received from the device. | |
2245 | */ | |
0cc43a18 | 2246 | s32 i2c_smbus_read_word_data(const struct i2c_client *client, u8 command) |
1da177e4 LT |
2247 | { |
2248 | union i2c_smbus_data data; | |
24a5bb7b DB |
2249 | int status; |
2250 | ||
2251 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
2252 | I2C_SMBUS_READ, command, | |
2253 | I2C_SMBUS_WORD_DATA, &data); | |
2254 | return (status < 0) ? status : data.word; | |
1da177e4 | 2255 | } |
c0564606 | 2256 | EXPORT_SYMBOL(i2c_smbus_read_word_data); |
1da177e4 | 2257 | |
a1cdedac DB |
2258 | /** |
2259 | * i2c_smbus_write_word_data - SMBus "write word" protocol | |
2260 | * @client: Handle to slave device | |
2261 | * @command: Byte interpreted by slave | |
2262 | * @value: 16-bit "word" being written | |
2263 | * | |
2264 | * This executes the SMBus "write word" protocol, returning negative errno | |
2265 | * else zero on success. | |
2266 | */ | |
0cc43a18 JD |
2267 | s32 i2c_smbus_write_word_data(const struct i2c_client *client, u8 command, |
2268 | u16 value) | |
1da177e4 LT |
2269 | { |
2270 | union i2c_smbus_data data; | |
2271 | data.word = value; | |
7225acf4 FH |
2272 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2273 | I2C_SMBUS_WRITE, command, | |
2274 | I2C_SMBUS_WORD_DATA, &data); | |
1da177e4 | 2275 | } |
c0564606 | 2276 | EXPORT_SYMBOL(i2c_smbus_write_word_data); |
1da177e4 | 2277 | |
a64ec07d | 2278 | /** |
a1cdedac | 2279 | * i2c_smbus_read_block_data - SMBus "block read" protocol |
a64ec07d | 2280 | * @client: Handle to slave device |
a1cdedac | 2281 | * @command: Byte interpreted by slave |
a64ec07d DB |
2282 | * @values: Byte array into which data will be read; big enough to hold |
2283 | * the data returned by the slave. SMBus allows at most 32 bytes. | |
2284 | * | |
a1cdedac DB |
2285 | * This executes the SMBus "block read" protocol, returning negative errno |
2286 | * else the number of data bytes in the slave's response. | |
a64ec07d DB |
2287 | * |
2288 | * Note that using this function requires that the client's adapter support | |
2289 | * the I2C_FUNC_SMBUS_READ_BLOCK_DATA functionality. Not all adapter drivers | |
2290 | * support this; its emulation through I2C messaging relies on a specific | |
2291 | * mechanism (I2C_M_RECV_LEN) which may not be implemented. | |
2292 | */ | |
0cc43a18 | 2293 | s32 i2c_smbus_read_block_data(const struct i2c_client *client, u8 command, |
b86a1bc8 JD |
2294 | u8 *values) |
2295 | { | |
2296 | union i2c_smbus_data data; | |
24a5bb7b | 2297 | int status; |
b86a1bc8 | 2298 | |
24a5bb7b DB |
2299 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2300 | I2C_SMBUS_READ, command, | |
2301 | I2C_SMBUS_BLOCK_DATA, &data); | |
2302 | if (status) | |
2303 | return status; | |
b86a1bc8 JD |
2304 | |
2305 | memcpy(values, &data.block[1], data.block[0]); | |
2306 | return data.block[0]; | |
2307 | } | |
2308 | EXPORT_SYMBOL(i2c_smbus_read_block_data); | |
2309 | ||
a1cdedac DB |
2310 | /** |
2311 | * i2c_smbus_write_block_data - SMBus "block write" protocol | |
2312 | * @client: Handle to slave device | |
2313 | * @command: Byte interpreted by slave | |
2314 | * @length: Size of data block; SMBus allows at most 32 bytes | |
2315 | * @values: Byte array which will be written. | |
2316 | * | |
2317 | * This executes the SMBus "block write" protocol, returning negative errno | |
2318 | * else zero on success. | |
2319 | */ | |
0cc43a18 | 2320 | s32 i2c_smbus_write_block_data(const struct i2c_client *client, u8 command, |
46f5ed75 | 2321 | u8 length, const u8 *values) |
1da177e4 LT |
2322 | { |
2323 | union i2c_smbus_data data; | |
7656032b | 2324 | |
1da177e4 LT |
2325 | if (length > I2C_SMBUS_BLOCK_MAX) |
2326 | length = I2C_SMBUS_BLOCK_MAX; | |
1da177e4 | 2327 | data.block[0] = length; |
7656032b | 2328 | memcpy(&data.block[1], values, length); |
7225acf4 FH |
2329 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2330 | I2C_SMBUS_WRITE, command, | |
2331 | I2C_SMBUS_BLOCK_DATA, &data); | |
1da177e4 | 2332 | } |
c0564606 | 2333 | EXPORT_SYMBOL(i2c_smbus_write_block_data); |
1da177e4 LT |
2334 | |
2335 | /* Returns the number of read bytes */ | |
0cc43a18 | 2336 | s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, u8 command, |
4b2643d7 | 2337 | u8 length, u8 *values) |
1da177e4 LT |
2338 | { |
2339 | union i2c_smbus_data data; | |
24a5bb7b | 2340 | int status; |
7656032b | 2341 | |
4b2643d7 JD |
2342 | if (length > I2C_SMBUS_BLOCK_MAX) |
2343 | length = I2C_SMBUS_BLOCK_MAX; | |
2344 | data.block[0] = length; | |
24a5bb7b DB |
2345 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2346 | I2C_SMBUS_READ, command, | |
2347 | I2C_SMBUS_I2C_BLOCK_DATA, &data); | |
2348 | if (status < 0) | |
2349 | return status; | |
7656032b JD |
2350 | |
2351 | memcpy(values, &data.block[1], data.block[0]); | |
2352 | return data.block[0]; | |
1da177e4 | 2353 | } |
c0564606 | 2354 | EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data); |
1da177e4 | 2355 | |
0cc43a18 | 2356 | s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, u8 command, |
46f5ed75 | 2357 | u8 length, const u8 *values) |
21bbd691 JD |
2358 | { |
2359 | union i2c_smbus_data data; | |
2360 | ||
2361 | if (length > I2C_SMBUS_BLOCK_MAX) | |
2362 | length = I2C_SMBUS_BLOCK_MAX; | |
2363 | data.block[0] = length; | |
2364 | memcpy(data.block + 1, values, length); | |
2365 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
2366 | I2C_SMBUS_WRITE, command, | |
2367 | I2C_SMBUS_I2C_BLOCK_DATA, &data); | |
2368 | } | |
c0564606 | 2369 | EXPORT_SYMBOL(i2c_smbus_write_i2c_block_data); |
21bbd691 | 2370 | |
438d6c2c | 2371 | /* Simulate a SMBus command using the i2c protocol |
1da177e4 | 2372 | No checking of parameters is done! */ |
7225acf4 FH |
2373 | static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, |
2374 | unsigned short flags, | |
2375 | char read_write, u8 command, int size, | |
2376 | union i2c_smbus_data *data) | |
1da177e4 LT |
2377 | { |
2378 | /* So we need to generate a series of msgs. In the case of writing, we | |
2379 | need to use only one message; when reading, we need two. We initialize | |
2380 | most things with sane defaults, to keep the code below somewhat | |
2381 | simpler. */ | |
5c50d188 HI |
2382 | unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3]; |
2383 | unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2]; | |
7225acf4 | 2384 | int num = read_write == I2C_SMBUS_READ ? 2 : 1; |
1da177e4 | 2385 | int i; |
421ef47b | 2386 | u8 partial_pec = 0; |
24a5bb7b | 2387 | int status; |
230da094 S |
2388 | struct i2c_msg msg[2] = { |
2389 | { | |
2390 | .addr = addr, | |
2391 | .flags = flags, | |
2392 | .len = 1, | |
2393 | .buf = msgbuf0, | |
2394 | }, { | |
2395 | .addr = addr, | |
2396 | .flags = flags | I2C_M_RD, | |
2397 | .len = 0, | |
2398 | .buf = msgbuf1, | |
2399 | }, | |
2400 | }; | |
1da177e4 LT |
2401 | |
2402 | msgbuf0[0] = command; | |
7225acf4 | 2403 | switch (size) { |
1da177e4 LT |
2404 | case I2C_SMBUS_QUICK: |
2405 | msg[0].len = 0; | |
2406 | /* Special case: The read/write field is used as data */ | |
f29d2e02 RK |
2407 | msg[0].flags = flags | (read_write == I2C_SMBUS_READ ? |
2408 | I2C_M_RD : 0); | |
1da177e4 LT |
2409 | num = 1; |
2410 | break; | |
2411 | case I2C_SMBUS_BYTE: | |
2412 | if (read_write == I2C_SMBUS_READ) { | |
2413 | /* Special case: only a read! */ | |
2414 | msg[0].flags = I2C_M_RD | flags; | |
2415 | num = 1; | |
2416 | } | |
2417 | break; | |
2418 | case I2C_SMBUS_BYTE_DATA: | |
2419 | if (read_write == I2C_SMBUS_READ) | |
2420 | msg[1].len = 1; | |
2421 | else { | |
2422 | msg[0].len = 2; | |
2423 | msgbuf0[1] = data->byte; | |
2424 | } | |
2425 | break; | |
2426 | case I2C_SMBUS_WORD_DATA: | |
2427 | if (read_write == I2C_SMBUS_READ) | |
2428 | msg[1].len = 2; | |
2429 | else { | |
7225acf4 | 2430 | msg[0].len = 3; |
1da177e4 | 2431 | msgbuf0[1] = data->word & 0xff; |
7eff82c8 | 2432 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
2433 | } |
2434 | break; | |
2435 | case I2C_SMBUS_PROC_CALL: | |
2436 | num = 2; /* Special case */ | |
2437 | read_write = I2C_SMBUS_READ; | |
2438 | msg[0].len = 3; | |
2439 | msg[1].len = 2; | |
2440 | msgbuf0[1] = data->word & 0xff; | |
7eff82c8 | 2441 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
2442 | break; |
2443 | case I2C_SMBUS_BLOCK_DATA: | |
1da177e4 | 2444 | if (read_write == I2C_SMBUS_READ) { |
209d27c3 JD |
2445 | msg[1].flags |= I2C_M_RECV_LEN; |
2446 | msg[1].len = 1; /* block length will be added by | |
2447 | the underlying bus driver */ | |
1da177e4 LT |
2448 | } else { |
2449 | msg[0].len = data->block[0] + 2; | |
2450 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 2) { | |
24a5bb7b DB |
2451 | dev_err(&adapter->dev, |
2452 | "Invalid block write size %d\n", | |
2453 | data->block[0]); | |
2454 | return -EINVAL; | |
1da177e4 | 2455 | } |
5c50d188 | 2456 | for (i = 1; i < msg[0].len; i++) |
1da177e4 LT |
2457 | msgbuf0[i] = data->block[i-1]; |
2458 | } | |
2459 | break; | |
2460 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
209d27c3 JD |
2461 | num = 2; /* Another special case */ |
2462 | read_write = I2C_SMBUS_READ; | |
2463 | if (data->block[0] > I2C_SMBUS_BLOCK_MAX) { | |
24a5bb7b DB |
2464 | dev_err(&adapter->dev, |
2465 | "Invalid block write size %d\n", | |
209d27c3 | 2466 | data->block[0]); |
24a5bb7b | 2467 | return -EINVAL; |
209d27c3 JD |
2468 | } |
2469 | msg[0].len = data->block[0] + 2; | |
2470 | for (i = 1; i < msg[0].len; i++) | |
2471 | msgbuf0[i] = data->block[i-1]; | |
2472 | msg[1].flags |= I2C_M_RECV_LEN; | |
2473 | msg[1].len = 1; /* block length will be added by | |
2474 | the underlying bus driver */ | |
2475 | break; | |
1da177e4 LT |
2476 | case I2C_SMBUS_I2C_BLOCK_DATA: |
2477 | if (read_write == I2C_SMBUS_READ) { | |
4b2643d7 | 2478 | msg[1].len = data->block[0]; |
1da177e4 LT |
2479 | } else { |
2480 | msg[0].len = data->block[0] + 1; | |
30dac746 | 2481 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 1) { |
24a5bb7b DB |
2482 | dev_err(&adapter->dev, |
2483 | "Invalid block write size %d\n", | |
2484 | data->block[0]); | |
2485 | return -EINVAL; | |
1da177e4 LT |
2486 | } |
2487 | for (i = 1; i <= data->block[0]; i++) | |
2488 | msgbuf0[i] = data->block[i]; | |
2489 | } | |
2490 | break; | |
2491 | default: | |
24a5bb7b DB |
2492 | dev_err(&adapter->dev, "Unsupported transaction %d\n", size); |
2493 | return -EOPNOTSUPP; | |
1da177e4 LT |
2494 | } |
2495 | ||
421ef47b JD |
2496 | i = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK |
2497 | && size != I2C_SMBUS_I2C_BLOCK_DATA); | |
2498 | if (i) { | |
2499 | /* Compute PEC if first message is a write */ | |
2500 | if (!(msg[0].flags & I2C_M_RD)) { | |
438d6c2c | 2501 | if (num == 1) /* Write only */ |
421ef47b JD |
2502 | i2c_smbus_add_pec(&msg[0]); |
2503 | else /* Write followed by read */ | |
2504 | partial_pec = i2c_smbus_msg_pec(0, &msg[0]); | |
2505 | } | |
2506 | /* Ask for PEC if last message is a read */ | |
2507 | if (msg[num-1].flags & I2C_M_RD) | |
438d6c2c | 2508 | msg[num-1].len++; |
421ef47b JD |
2509 | } |
2510 | ||
24a5bb7b DB |
2511 | status = i2c_transfer(adapter, msg, num); |
2512 | if (status < 0) | |
2513 | return status; | |
1da177e4 | 2514 | |
421ef47b JD |
2515 | /* Check PEC if last message is a read */ |
2516 | if (i && (msg[num-1].flags & I2C_M_RD)) { | |
24a5bb7b DB |
2517 | status = i2c_smbus_check_pec(partial_pec, &msg[num-1]); |
2518 | if (status < 0) | |
2519 | return status; | |
421ef47b JD |
2520 | } |
2521 | ||
1da177e4 | 2522 | if (read_write == I2C_SMBUS_READ) |
7225acf4 FH |
2523 | switch (size) { |
2524 | case I2C_SMBUS_BYTE: | |
2525 | data->byte = msgbuf0[0]; | |
2526 | break; | |
2527 | case I2C_SMBUS_BYTE_DATA: | |
2528 | data->byte = msgbuf1[0]; | |
2529 | break; | |
2530 | case I2C_SMBUS_WORD_DATA: | |
2531 | case I2C_SMBUS_PROC_CALL: | |
2532 | data->word = msgbuf1[0] | (msgbuf1[1] << 8); | |
2533 | break; | |
2534 | case I2C_SMBUS_I2C_BLOCK_DATA: | |
2535 | for (i = 0; i < data->block[0]; i++) | |
2536 | data->block[i+1] = msgbuf1[i]; | |
2537 | break; | |
2538 | case I2C_SMBUS_BLOCK_DATA: | |
2539 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
2540 | for (i = 0; i < msgbuf1[0] + 1; i++) | |
2541 | data->block[i] = msgbuf1[i]; | |
2542 | break; | |
1da177e4 LT |
2543 | } |
2544 | return 0; | |
2545 | } | |
2546 | ||
a1cdedac DB |
2547 | /** |
2548 | * i2c_smbus_xfer - execute SMBus protocol operations | |
2549 | * @adapter: Handle to I2C bus | |
2550 | * @addr: Address of SMBus slave on that bus | |
2551 | * @flags: I2C_CLIENT_* flags (usually zero or I2C_CLIENT_PEC) | |
2552 | * @read_write: I2C_SMBUS_READ or I2C_SMBUS_WRITE | |
2553 | * @command: Byte interpreted by slave, for protocols which use such bytes | |
2554 | * @protocol: SMBus protocol operation to execute, such as I2C_SMBUS_PROC_CALL | |
2555 | * @data: Data to be read or written | |
2556 | * | |
2557 | * This executes an SMBus protocol operation, and returns a negative | |
2558 | * errno code else zero on success. | |
2559 | */ | |
09b8ce0a | 2560 | s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags, |
a1cdedac | 2561 | char read_write, u8 command, int protocol, |
09b8ce0a | 2562 | union i2c_smbus_data *data) |
1da177e4 | 2563 | { |
66b650f0 CW |
2564 | unsigned long orig_jiffies; |
2565 | int try; | |
1da177e4 | 2566 | s32 res; |
1da177e4 | 2567 | |
8a325997 DH |
2568 | /* If enabled, the following two tracepoints are conditional on |
2569 | * read_write and protocol. | |
2570 | */ | |
2571 | trace_smbus_write(adapter, addr, flags, read_write, | |
2572 | command, protocol, data); | |
2573 | trace_smbus_read(adapter, addr, flags, read_write, | |
2574 | command, protocol); | |
2575 | ||
d47726c5 | 2576 | flags &= I2C_M_TEN | I2C_CLIENT_PEC | I2C_CLIENT_SCCB; |
1da177e4 LT |
2577 | |
2578 | if (adapter->algo->smbus_xfer) { | |
fe61e07e | 2579 | i2c_lock_adapter(adapter); |
66b650f0 CW |
2580 | |
2581 | /* Retry automatically on arbitration loss */ | |
2582 | orig_jiffies = jiffies; | |
2583 | for (res = 0, try = 0; try <= adapter->retries; try++) { | |
2584 | res = adapter->algo->smbus_xfer(adapter, addr, flags, | |
2585 | read_write, command, | |
2586 | protocol, data); | |
2587 | if (res != -EAGAIN) | |
2588 | break; | |
2589 | if (time_after(jiffies, | |
2590 | orig_jiffies + adapter->timeout)) | |
2591 | break; | |
2592 | } | |
fe61e07e | 2593 | i2c_unlock_adapter(adapter); |
1da177e4 | 2594 | |
72fc2c7f | 2595 | if (res != -EOPNOTSUPP || !adapter->algo->master_xfer) |
8a325997 | 2596 | goto trace; |
72fc2c7f LP |
2597 | /* |
2598 | * Fall back to i2c_smbus_xfer_emulated if the adapter doesn't | |
2599 | * implement native support for the SMBus operation. | |
2600 | */ | |
2601 | } | |
2602 | ||
8a325997 DH |
2603 | res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write, |
2604 | command, protocol, data); | |
2605 | ||
2606 | trace: | |
2607 | /* If enabled, the reply tracepoint is conditional on read_write. */ | |
2608 | trace_smbus_reply(adapter, addr, flags, read_write, | |
2609 | command, protocol, data); | |
2610 | trace_smbus_result(adapter, addr, flags, read_write, | |
2611 | command, protocol, res); | |
2612 | ||
2613 | return res; | |
1da177e4 | 2614 | } |
1da177e4 | 2615 | EXPORT_SYMBOL(i2c_smbus_xfer); |
1da177e4 LT |
2616 | |
2617 | MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); | |
2618 | MODULE_DESCRIPTION("I2C-Bus main module"); | |
2619 | MODULE_LICENSE("GPL"); |