Commit | Line | Data |
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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 | |
17 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ | |
18 | /* ------------------------------------------------------------------------- */ | |
19 | ||
96de0e25 | 20 | /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>. |
1da177e4 | 21 | All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl> |
421ef47b JD |
22 | SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and |
23 | Jean Delvare <khali@linux-fr.org> */ | |
1da177e4 | 24 | |
1da177e4 LT |
25 | #include <linux/module.h> |
26 | #include <linux/kernel.h> | |
27 | #include <linux/errno.h> | |
28 | #include <linux/slab.h> | |
29 | #include <linux/i2c.h> | |
30 | #include <linux/init.h> | |
31 | #include <linux/idr.h> | |
32 | #include <linux/seq_file.h> | |
d052d1be | 33 | #include <linux/platform_device.h> |
b3585e4f | 34 | #include <linux/mutex.h> |
b8d6f45b | 35 | #include <linux/completion.h> |
cea443a8 MR |
36 | #include <linux/hardirq.h> |
37 | #include <linux/irqflags.h> | |
6188e10d | 38 | #include <linux/semaphore.h> |
1da177e4 LT |
39 | #include <asm/uaccess.h> |
40 | ||
9c1600ed DB |
41 | #include "i2c-core.h" |
42 | ||
1da177e4 | 43 | |
caada32a | 44 | static DEFINE_MUTEX(core_lock); |
1da177e4 LT |
45 | static DEFINE_IDR(i2c_adapter_idr); |
46 | ||
a1d9e6e4 | 47 | #define is_newstyle_driver(d) ((d)->probe || (d)->remove) |
f37dd80a DB |
48 | |
49 | /* ------------------------------------------------------------------------- */ | |
50 | ||
d2653e92 JD |
51 | static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, |
52 | const struct i2c_client *client) | |
53 | { | |
54 | while (id->name[0]) { | |
55 | if (strcmp(client->name, id->name) == 0) | |
56 | return id; | |
57 | id++; | |
58 | } | |
59 | return NULL; | |
60 | } | |
61 | ||
1da177e4 LT |
62 | static int i2c_device_match(struct device *dev, struct device_driver *drv) |
63 | { | |
7b4fbc50 DB |
64 | struct i2c_client *client = to_i2c_client(dev); |
65 | struct i2c_driver *driver = to_i2c_driver(drv); | |
66 | ||
67 | /* make legacy i2c drivers bypass driver model probing entirely; | |
68 | * such drivers scan each i2c adapter/bus themselves. | |
69 | */ | |
a1d9e6e4 | 70 | if (!is_newstyle_driver(driver)) |
7b4fbc50 DB |
71 | return 0; |
72 | ||
d2653e92 JD |
73 | /* match on an id table if there is one */ |
74 | if (driver->id_table) | |
75 | return i2c_match_id(driver->id_table, client) != NULL; | |
76 | ||
7b4fbc50 DB |
77 | /* new style drivers use the same kind of driver matching policy |
78 | * as platform devices or SPI: compare device and driver IDs. | |
79 | */ | |
80 | return strcmp(client->driver_name, drv->name) == 0; | |
1da177e4 LT |
81 | } |
82 | ||
7b4fbc50 DB |
83 | #ifdef CONFIG_HOTPLUG |
84 | ||
85 | /* uevent helps with hotplug: modprobe -q $(MODALIAS) */ | |
7eff2e7a | 86 | static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env) |
7b4fbc50 DB |
87 | { |
88 | struct i2c_client *client = to_i2c_client(dev); | |
7b4fbc50 DB |
89 | |
90 | /* by definition, legacy drivers can't hotplug */ | |
d2653e92 | 91 | if (dev->driver) |
7b4fbc50 DB |
92 | return 0; |
93 | ||
d2653e92 JD |
94 | if (client->driver_name[0]) { |
95 | if (add_uevent_var(env, "MODALIAS=%s", client->driver_name)) | |
96 | return -ENOMEM; | |
97 | } else { | |
98 | if (add_uevent_var(env, "MODALIAS=%s%s", | |
99 | I2C_MODULE_PREFIX, client->name)) | |
100 | return -ENOMEM; | |
101 | } | |
7b4fbc50 DB |
102 | dev_dbg(dev, "uevent\n"); |
103 | return 0; | |
104 | } | |
105 | ||
106 | #else | |
107 | #define i2c_device_uevent NULL | |
108 | #endif /* CONFIG_HOTPLUG */ | |
109 | ||
f37dd80a | 110 | static int i2c_device_probe(struct device *dev) |
1da177e4 | 111 | { |
7b4fbc50 DB |
112 | struct i2c_client *client = to_i2c_client(dev); |
113 | struct i2c_driver *driver = to_i2c_driver(dev->driver); | |
d2653e92 | 114 | const struct i2c_device_id *id; |
50c3304a | 115 | int status; |
7b4fbc50 DB |
116 | |
117 | if (!driver->probe) | |
118 | return -ENODEV; | |
119 | client->driver = driver; | |
120 | dev_dbg(dev, "probe\n"); | |
d2653e92 JD |
121 | |
122 | if (driver->id_table) | |
123 | id = i2c_match_id(driver->id_table, client); | |
124 | else | |
125 | id = NULL; | |
126 | status = driver->probe(client, id); | |
50c3304a HV |
127 | if (status) |
128 | client->driver = NULL; | |
129 | return status; | |
f37dd80a | 130 | } |
1da177e4 | 131 | |
f37dd80a DB |
132 | static int i2c_device_remove(struct device *dev) |
133 | { | |
a1d9e6e4 DB |
134 | struct i2c_client *client = to_i2c_client(dev); |
135 | struct i2c_driver *driver; | |
136 | int status; | |
137 | ||
138 | if (!dev->driver) | |
139 | return 0; | |
140 | ||
141 | driver = to_i2c_driver(dev->driver); | |
142 | if (driver->remove) { | |
143 | dev_dbg(dev, "remove\n"); | |
144 | status = driver->remove(client); | |
145 | } else { | |
146 | dev->driver = NULL; | |
147 | status = 0; | |
148 | } | |
149 | if (status == 0) | |
150 | client->driver = NULL; | |
151 | return status; | |
1da177e4 LT |
152 | } |
153 | ||
f37dd80a | 154 | static void i2c_device_shutdown(struct device *dev) |
1da177e4 | 155 | { |
f37dd80a DB |
156 | struct i2c_driver *driver; |
157 | ||
158 | if (!dev->driver) | |
159 | return; | |
160 | driver = to_i2c_driver(dev->driver); | |
161 | if (driver->shutdown) | |
162 | driver->shutdown(to_i2c_client(dev)); | |
1da177e4 LT |
163 | } |
164 | ||
f37dd80a | 165 | static int i2c_device_suspend(struct device * dev, pm_message_t mesg) |
1da177e4 | 166 | { |
f37dd80a DB |
167 | struct i2c_driver *driver; |
168 | ||
169 | if (!dev->driver) | |
170 | return 0; | |
171 | driver = to_i2c_driver(dev->driver); | |
172 | if (!driver->suspend) | |
173 | return 0; | |
174 | return driver->suspend(to_i2c_client(dev), mesg); | |
1da177e4 LT |
175 | } |
176 | ||
f37dd80a | 177 | static int i2c_device_resume(struct device * dev) |
1da177e4 | 178 | { |
f37dd80a DB |
179 | struct i2c_driver *driver; |
180 | ||
181 | if (!dev->driver) | |
182 | return 0; | |
183 | driver = to_i2c_driver(dev->driver); | |
184 | if (!driver->resume) | |
185 | return 0; | |
186 | return driver->resume(to_i2c_client(dev)); | |
1da177e4 LT |
187 | } |
188 | ||
7b4fbc50 DB |
189 | static void i2c_client_release(struct device *dev) |
190 | { | |
191 | struct i2c_client *client = to_i2c_client(dev); | |
192 | complete(&client->released); | |
193 | } | |
194 | ||
9c1600ed DB |
195 | static void i2c_client_dev_release(struct device *dev) |
196 | { | |
197 | kfree(to_i2c_client(dev)); | |
198 | } | |
199 | ||
7b4fbc50 DB |
200 | static ssize_t show_client_name(struct device *dev, struct device_attribute *attr, char *buf) |
201 | { | |
202 | struct i2c_client *client = to_i2c_client(dev); | |
203 | return sprintf(buf, "%s\n", client->name); | |
204 | } | |
205 | ||
206 | static ssize_t show_modalias(struct device *dev, struct device_attribute *attr, char *buf) | |
207 | { | |
208 | struct i2c_client *client = to_i2c_client(dev); | |
d2653e92 | 209 | return client->driver_name[0] |
7b4fbc50 | 210 | ? sprintf(buf, "%s\n", client->driver_name) |
d2653e92 | 211 | : sprintf(buf, "%s%s\n", I2C_MODULE_PREFIX, client->name); |
7b4fbc50 DB |
212 | } |
213 | ||
214 | static struct device_attribute i2c_dev_attrs[] = { | |
215 | __ATTR(name, S_IRUGO, show_client_name, NULL), | |
216 | /* modalias helps coldplug: modprobe $(cat .../modalias) */ | |
217 | __ATTR(modalias, S_IRUGO, show_modalias, NULL), | |
218 | { }, | |
219 | }; | |
220 | ||
83eaaed0 | 221 | static struct bus_type i2c_bus_type = { |
f37dd80a | 222 | .name = "i2c", |
7b4fbc50 | 223 | .dev_attrs = i2c_dev_attrs, |
f37dd80a | 224 | .match = i2c_device_match, |
7b4fbc50 | 225 | .uevent = i2c_device_uevent, |
f37dd80a DB |
226 | .probe = i2c_device_probe, |
227 | .remove = i2c_device_remove, | |
228 | .shutdown = i2c_device_shutdown, | |
229 | .suspend = i2c_device_suspend, | |
230 | .resume = i2c_device_resume, | |
b864c7d5 RK |
231 | }; |
232 | ||
9b766b81 DB |
233 | |
234 | /** | |
235 | * i2c_verify_client - return parameter as i2c_client, or NULL | |
236 | * @dev: device, probably from some driver model iterator | |
237 | * | |
238 | * When traversing the driver model tree, perhaps using driver model | |
239 | * iterators like @device_for_each_child(), you can't assume very much | |
240 | * about the nodes you find. Use this function to avoid oopses caused | |
241 | * by wrongly treating some non-I2C device as an i2c_client. | |
242 | */ | |
243 | struct i2c_client *i2c_verify_client(struct device *dev) | |
244 | { | |
245 | return (dev->bus == &i2c_bus_type) | |
246 | ? to_i2c_client(dev) | |
247 | : NULL; | |
248 | } | |
249 | EXPORT_SYMBOL(i2c_verify_client); | |
250 | ||
251 | ||
9c1600ed DB |
252 | /** |
253 | * i2c_new_device - instantiate an i2c device for use with a new style driver | |
254 | * @adap: the adapter managing the device | |
255 | * @info: describes one I2C device; bus_num is ignored | |
d64f73be | 256 | * Context: can sleep |
9c1600ed DB |
257 | * |
258 | * Create a device to work with a new style i2c driver, where binding is | |
259 | * handled through driver model probe()/remove() methods. This call is not | |
260 | * appropriate for use by mainboad initialization logic, which usually runs | |
261 | * during an arch_initcall() long before any i2c_adapter could exist. | |
262 | * | |
263 | * This returns the new i2c client, which may be saved for later use with | |
264 | * i2c_unregister_device(); or NULL to indicate an error. | |
265 | */ | |
266 | struct i2c_client * | |
267 | i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) | |
268 | { | |
269 | struct i2c_client *client; | |
270 | int status; | |
271 | ||
272 | client = kzalloc(sizeof *client, GFP_KERNEL); | |
273 | if (!client) | |
274 | return NULL; | |
275 | ||
276 | client->adapter = adap; | |
277 | ||
278 | client->dev.platform_data = info->platform_data; | |
3bbb835d DB |
279 | device_init_wakeup(&client->dev, info->flags & I2C_CLIENT_WAKE); |
280 | ||
281 | client->flags = info->flags & ~I2C_CLIENT_WAKE; | |
9c1600ed DB |
282 | client->addr = info->addr; |
283 | client->irq = info->irq; | |
284 | ||
285 | strlcpy(client->driver_name, info->driver_name, | |
286 | sizeof(client->driver_name)); | |
287 | strlcpy(client->name, info->type, sizeof(client->name)); | |
288 | ||
289 | /* a new style driver may be bound to this device when we | |
290 | * return from this function, or any later moment (e.g. maybe | |
291 | * hotplugging will load the driver module). and the device | |
292 | * refcount model is the standard driver model one. | |
293 | */ | |
294 | status = i2c_attach_client(client); | |
295 | if (status < 0) { | |
296 | kfree(client); | |
297 | client = NULL; | |
298 | } | |
299 | return client; | |
300 | } | |
301 | EXPORT_SYMBOL_GPL(i2c_new_device); | |
302 | ||
303 | ||
304 | /** | |
305 | * i2c_unregister_device - reverse effect of i2c_new_device() | |
306 | * @client: value returned from i2c_new_device() | |
d64f73be | 307 | * Context: can sleep |
9c1600ed DB |
308 | */ |
309 | void i2c_unregister_device(struct i2c_client *client) | |
a1d9e6e4 DB |
310 | { |
311 | struct i2c_adapter *adapter = client->adapter; | |
312 | struct i2c_driver *driver = client->driver; | |
313 | ||
314 | if (driver && !is_newstyle_driver(driver)) { | |
315 | dev_err(&client->dev, "can't unregister devices " | |
316 | "with legacy drivers\n"); | |
317 | WARN_ON(1); | |
318 | return; | |
319 | } | |
320 | ||
321 | mutex_lock(&adapter->clist_lock); | |
322 | list_del(&client->list); | |
323 | mutex_unlock(&adapter->clist_lock); | |
324 | ||
325 | device_unregister(&client->dev); | |
326 | } | |
9c1600ed | 327 | EXPORT_SYMBOL_GPL(i2c_unregister_device); |
a1d9e6e4 DB |
328 | |
329 | ||
d2653e92 JD |
330 | static int dummy_probe(struct i2c_client *client, |
331 | const struct i2c_device_id *id) | |
332 | { | |
333 | return 0; | |
334 | } | |
335 | ||
336 | static int dummy_remove(struct i2c_client *client) | |
e9f1373b DB |
337 | { |
338 | return 0; | |
339 | } | |
340 | ||
341 | static struct i2c_driver dummy_driver = { | |
342 | .driver.name = "dummy", | |
d2653e92 JD |
343 | .probe = dummy_probe, |
344 | .remove = dummy_remove, | |
e9f1373b DB |
345 | }; |
346 | ||
347 | /** | |
348 | * i2c_new_dummy - return a new i2c device bound to a dummy driver | |
349 | * @adapter: the adapter managing the device | |
350 | * @address: seven bit address to be used | |
351 | * @type: optional label used for i2c_client.name | |
352 | * Context: can sleep | |
353 | * | |
354 | * This returns an I2C client bound to the "dummy" driver, intended for use | |
355 | * with devices that consume multiple addresses. Examples of such chips | |
356 | * include various EEPROMS (like 24c04 and 24c08 models). | |
357 | * | |
358 | * These dummy devices have two main uses. First, most I2C and SMBus calls | |
359 | * except i2c_transfer() need a client handle; the dummy will be that handle. | |
360 | * And second, this prevents the specified address from being bound to a | |
361 | * different driver. | |
362 | * | |
363 | * This returns the new i2c client, which should be saved for later use with | |
364 | * i2c_unregister_device(); or NULL to indicate an error. | |
365 | */ | |
366 | struct i2c_client * | |
367 | i2c_new_dummy(struct i2c_adapter *adapter, u16 address, const char *type) | |
368 | { | |
369 | struct i2c_board_info info = { | |
370 | .driver_name = "dummy", | |
371 | .addr = address, | |
372 | }; | |
373 | ||
374 | if (type) | |
375 | strlcpy(info.type, type, sizeof info.type); | |
376 | return i2c_new_device(adapter, &info); | |
377 | } | |
378 | EXPORT_SYMBOL_GPL(i2c_new_dummy); | |
379 | ||
f37dd80a DB |
380 | /* ------------------------------------------------------------------------- */ |
381 | ||
16ffadfc DB |
382 | /* I2C bus adapters -- one roots each I2C or SMBUS segment */ |
383 | ||
83eaaed0 | 384 | static void i2c_adapter_dev_release(struct device *dev) |
1da177e4 | 385 | { |
ef2c8321 | 386 | struct i2c_adapter *adap = to_i2c_adapter(dev); |
1da177e4 LT |
387 | complete(&adap->dev_released); |
388 | } | |
389 | ||
16ffadfc DB |
390 | static ssize_t |
391 | show_adapter_name(struct device *dev, struct device_attribute *attr, char *buf) | |
392 | { | |
ef2c8321 | 393 | struct i2c_adapter *adap = to_i2c_adapter(dev); |
16ffadfc DB |
394 | return sprintf(buf, "%s\n", adap->name); |
395 | } | |
b119dc3f | 396 | |
16ffadfc DB |
397 | static struct device_attribute i2c_adapter_attrs[] = { |
398 | __ATTR(name, S_IRUGO, show_adapter_name, NULL), | |
399 | { }, | |
400 | }; | |
b119dc3f | 401 | |
83eaaed0 | 402 | static struct class i2c_adapter_class = { |
b119dc3f DB |
403 | .owner = THIS_MODULE, |
404 | .name = "i2c-adapter", | |
16ffadfc | 405 | .dev_attrs = i2c_adapter_attrs, |
1da177e4 LT |
406 | }; |
407 | ||
9c1600ed DB |
408 | static void i2c_scan_static_board_info(struct i2c_adapter *adapter) |
409 | { | |
410 | struct i2c_devinfo *devinfo; | |
411 | ||
412 | mutex_lock(&__i2c_board_lock); | |
413 | list_for_each_entry(devinfo, &__i2c_board_list, list) { | |
414 | if (devinfo->busnum == adapter->nr | |
415 | && !i2c_new_device(adapter, | |
416 | &devinfo->board_info)) | |
417 | printk(KERN_ERR "i2c-core: can't create i2c%d-%04x\n", | |
418 | i2c_adapter_id(adapter), | |
419 | devinfo->board_info.addr); | |
420 | } | |
421 | mutex_unlock(&__i2c_board_lock); | |
422 | } | |
423 | ||
026526f5 JD |
424 | static int i2c_do_add_adapter(struct device_driver *d, void *data) |
425 | { | |
426 | struct i2c_driver *driver = to_i2c_driver(d); | |
427 | struct i2c_adapter *adap = data; | |
428 | ||
429 | if (driver->attach_adapter) { | |
430 | /* We ignore the return code; if it fails, too bad */ | |
431 | driver->attach_adapter(adap); | |
432 | } | |
433 | return 0; | |
434 | } | |
435 | ||
6e13e641 | 436 | static int i2c_register_adapter(struct i2c_adapter *adap) |
1da177e4 | 437 | { |
026526f5 | 438 | int res = 0, dummy; |
1da177e4 | 439 | |
5c085d36 IM |
440 | mutex_init(&adap->bus_lock); |
441 | mutex_init(&adap->clist_lock); | |
1da177e4 LT |
442 | INIT_LIST_HEAD(&adap->clients); |
443 | ||
caada32a | 444 | mutex_lock(&core_lock); |
6e13e641 | 445 | |
1da177e4 LT |
446 | /* Add the adapter to the driver core. |
447 | * If the parent pointer is not set up, | |
448 | * we add this adapter to the host bus. | |
449 | */ | |
b119dc3f | 450 | if (adap->dev.parent == NULL) { |
1da177e4 | 451 | adap->dev.parent = &platform_bus; |
fe2c8d51 JD |
452 | pr_debug("I2C adapter driver [%s] forgot to specify " |
453 | "physical device\n", adap->name); | |
b119dc3f | 454 | } |
1da177e4 | 455 | sprintf(adap->dev.bus_id, "i2c-%d", adap->nr); |
1da177e4 | 456 | adap->dev.release = &i2c_adapter_dev_release; |
fccb56e4 | 457 | adap->dev.class = &i2c_adapter_class; |
b119c6c9 JD |
458 | res = device_register(&adap->dev); |
459 | if (res) | |
460 | goto out_list; | |
1da177e4 | 461 | |
b6d7b3d1 JD |
462 | dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name); |
463 | ||
6e13e641 DB |
464 | /* create pre-declared device nodes for new-style drivers */ |
465 | if (adap->nr < __i2c_first_dynamic_bus_num) | |
466 | i2c_scan_static_board_info(adap); | |
467 | ||
7b4fbc50 | 468 | /* let legacy drivers scan this bus for matching devices */ |
026526f5 JD |
469 | dummy = bus_for_each_drv(&i2c_bus_type, NULL, adap, |
470 | i2c_do_add_adapter); | |
1da177e4 | 471 | |
1da177e4 | 472 | out_unlock: |
caada32a | 473 | mutex_unlock(&core_lock); |
1da177e4 | 474 | return res; |
b119c6c9 | 475 | |
b119c6c9 | 476 | out_list: |
b119c6c9 JD |
477 | idr_remove(&i2c_adapter_idr, adap->nr); |
478 | goto out_unlock; | |
1da177e4 LT |
479 | } |
480 | ||
6e13e641 DB |
481 | /** |
482 | * i2c_add_adapter - declare i2c adapter, use dynamic bus number | |
483 | * @adapter: the adapter to add | |
d64f73be | 484 | * Context: can sleep |
6e13e641 DB |
485 | * |
486 | * This routine is used to declare an I2C adapter when its bus number | |
487 | * doesn't matter. Examples: for I2C adapters dynamically added by | |
488 | * USB links or PCI plugin cards. | |
489 | * | |
490 | * When this returns zero, a new bus number was allocated and stored | |
491 | * in adap->nr, and the specified adapter became available for clients. | |
492 | * Otherwise, a negative errno value is returned. | |
493 | */ | |
494 | int i2c_add_adapter(struct i2c_adapter *adapter) | |
495 | { | |
496 | int id, res = 0; | |
497 | ||
498 | retry: | |
499 | if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) | |
500 | return -ENOMEM; | |
501 | ||
caada32a | 502 | mutex_lock(&core_lock); |
6e13e641 DB |
503 | /* "above" here means "above or equal to", sigh */ |
504 | res = idr_get_new_above(&i2c_adapter_idr, adapter, | |
505 | __i2c_first_dynamic_bus_num, &id); | |
caada32a | 506 | mutex_unlock(&core_lock); |
6e13e641 DB |
507 | |
508 | if (res < 0) { | |
509 | if (res == -EAGAIN) | |
510 | goto retry; | |
511 | return res; | |
512 | } | |
513 | ||
514 | adapter->nr = id; | |
515 | return i2c_register_adapter(adapter); | |
516 | } | |
517 | EXPORT_SYMBOL(i2c_add_adapter); | |
518 | ||
519 | /** | |
520 | * i2c_add_numbered_adapter - declare i2c adapter, use static bus number | |
521 | * @adap: the adapter to register (with adap->nr initialized) | |
d64f73be | 522 | * Context: can sleep |
6e13e641 DB |
523 | * |
524 | * This routine is used to declare an I2C adapter when its bus number | |
8c07e46f RD |
525 | * matters. For example, use it for I2C adapters from system-on-chip CPUs, |
526 | * or otherwise built in to the system's mainboard, and where i2c_board_info | |
6e13e641 DB |
527 | * is used to properly configure I2C devices. |
528 | * | |
529 | * If no devices have pre-been declared for this bus, then be sure to | |
530 | * register the adapter before any dynamically allocated ones. Otherwise | |
531 | * the required bus ID may not be available. | |
532 | * | |
533 | * When this returns zero, the specified adapter became available for | |
534 | * clients using the bus number provided in adap->nr. Also, the table | |
535 | * of I2C devices pre-declared using i2c_register_board_info() is scanned, | |
536 | * and the appropriate driver model device nodes are created. Otherwise, a | |
537 | * negative errno value is returned. | |
538 | */ | |
539 | int i2c_add_numbered_adapter(struct i2c_adapter *adap) | |
540 | { | |
541 | int id; | |
542 | int status; | |
543 | ||
544 | if (adap->nr & ~MAX_ID_MASK) | |
545 | return -EINVAL; | |
546 | ||
547 | retry: | |
548 | if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) | |
549 | return -ENOMEM; | |
550 | ||
caada32a | 551 | mutex_lock(&core_lock); |
6e13e641 DB |
552 | /* "above" here means "above or equal to", sigh; |
553 | * we need the "equal to" result to force the result | |
554 | */ | |
555 | status = idr_get_new_above(&i2c_adapter_idr, adap, adap->nr, &id); | |
556 | if (status == 0 && id != adap->nr) { | |
557 | status = -EBUSY; | |
558 | idr_remove(&i2c_adapter_idr, id); | |
559 | } | |
caada32a | 560 | mutex_unlock(&core_lock); |
6e13e641 DB |
561 | if (status == -EAGAIN) |
562 | goto retry; | |
563 | ||
564 | if (status == 0) | |
565 | status = i2c_register_adapter(adap); | |
566 | return status; | |
567 | } | |
568 | EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter); | |
569 | ||
026526f5 JD |
570 | static int i2c_do_del_adapter(struct device_driver *d, void *data) |
571 | { | |
572 | struct i2c_driver *driver = to_i2c_driver(d); | |
573 | struct i2c_adapter *adapter = data; | |
574 | int res; | |
575 | ||
576 | if (!driver->detach_adapter) | |
577 | return 0; | |
578 | res = driver->detach_adapter(adapter); | |
579 | if (res) | |
580 | dev_err(&adapter->dev, "detach_adapter failed (%d) " | |
581 | "for driver [%s]\n", res, driver->driver.name); | |
582 | return res; | |
583 | } | |
584 | ||
d64f73be DB |
585 | /** |
586 | * i2c_del_adapter - unregister I2C adapter | |
587 | * @adap: the adapter being unregistered | |
588 | * Context: can sleep | |
589 | * | |
590 | * This unregisters an I2C adapter which was previously registered | |
591 | * by @i2c_add_adapter or @i2c_add_numbered_adapter. | |
592 | */ | |
1da177e4 LT |
593 | int i2c_del_adapter(struct i2c_adapter *adap) |
594 | { | |
595 | struct list_head *item, *_n; | |
1da177e4 LT |
596 | struct i2c_client *client; |
597 | int res = 0; | |
598 | ||
caada32a | 599 | mutex_lock(&core_lock); |
1da177e4 LT |
600 | |
601 | /* First make sure that this adapter was ever added */ | |
87c6c229 | 602 | if (idr_find(&i2c_adapter_idr, adap->nr) != adap) { |
b6d7b3d1 JD |
603 | pr_debug("i2c-core: attempting to delete unregistered " |
604 | "adapter [%s]\n", adap->name); | |
1da177e4 LT |
605 | res = -EINVAL; |
606 | goto out_unlock; | |
607 | } | |
608 | ||
026526f5 JD |
609 | /* Tell drivers about this removal */ |
610 | res = bus_for_each_drv(&i2c_bus_type, NULL, adap, | |
611 | i2c_do_del_adapter); | |
612 | if (res) | |
613 | goto out_unlock; | |
1da177e4 LT |
614 | |
615 | /* detach any active clients. This must be done first, because | |
a551acc2 | 616 | * it can fail; in which case we give up. */ |
1da177e4 | 617 | list_for_each_safe(item, _n, &adap->clients) { |
a1d9e6e4 DB |
618 | struct i2c_driver *driver; |
619 | ||
1da177e4 | 620 | client = list_entry(item, struct i2c_client, list); |
a1d9e6e4 DB |
621 | driver = client->driver; |
622 | ||
623 | /* new style, follow standard driver model */ | |
624 | if (!driver || is_newstyle_driver(driver)) { | |
625 | i2c_unregister_device(client); | |
626 | continue; | |
627 | } | |
1da177e4 | 628 | |
a1d9e6e4 DB |
629 | /* legacy drivers create and remove clients themselves */ |
630 | if ((res = driver->detach_client(client))) { | |
b6d7b3d1 JD |
631 | dev_err(&adap->dev, "detach_client failed for client " |
632 | "[%s] at address 0x%02x\n", client->name, | |
1da177e4 LT |
633 | client->addr); |
634 | goto out_unlock; | |
635 | } | |
636 | } | |
637 | ||
638 | /* clean up the sysfs representation */ | |
639 | init_completion(&adap->dev_released); | |
1da177e4 | 640 | device_unregister(&adap->dev); |
1da177e4 LT |
641 | |
642 | /* wait for sysfs to drop all references */ | |
643 | wait_for_completion(&adap->dev_released); | |
1da177e4 | 644 | |
6e13e641 | 645 | /* free bus id */ |
1da177e4 LT |
646 | idr_remove(&i2c_adapter_idr, adap->nr); |
647 | ||
b6d7b3d1 | 648 | dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name); |
1da177e4 LT |
649 | |
650 | out_unlock: | |
caada32a | 651 | mutex_unlock(&core_lock); |
1da177e4 LT |
652 | return res; |
653 | } | |
c0564606 | 654 | EXPORT_SYMBOL(i2c_del_adapter); |
1da177e4 LT |
655 | |
656 | ||
7b4fbc50 DB |
657 | /* ------------------------------------------------------------------------- */ |
658 | ||
659 | /* | |
660 | * An i2c_driver is used with one or more i2c_client (device) nodes to access | |
661 | * i2c slave chips, on a bus instance associated with some i2c_adapter. There | |
662 | * are two models for binding the driver to its device: "new style" drivers | |
663 | * follow the standard Linux driver model and just respond to probe() calls | |
664 | * issued if the driver core sees they match(); "legacy" drivers create device | |
665 | * nodes themselves. | |
1da177e4 LT |
666 | */ |
667 | ||
de59cf9e | 668 | int i2c_register_driver(struct module *owner, struct i2c_driver *driver) |
1da177e4 | 669 | { |
7eebcb7c | 670 | int res; |
1da177e4 | 671 | |
7b4fbc50 | 672 | /* new style driver methods can't mix with legacy ones */ |
a1d9e6e4 | 673 | if (is_newstyle_driver(driver)) { |
7b4fbc50 DB |
674 | if (driver->attach_adapter || driver->detach_adapter |
675 | || driver->detach_client) { | |
676 | printk(KERN_WARNING | |
677 | "i2c-core: driver [%s] is confused\n", | |
678 | driver->driver.name); | |
679 | return -EINVAL; | |
680 | } | |
681 | } | |
682 | ||
1da177e4 | 683 | /* add the driver to the list of i2c drivers in the driver core */ |
de59cf9e | 684 | driver->driver.owner = owner; |
1da177e4 | 685 | driver->driver.bus = &i2c_bus_type; |
1da177e4 | 686 | |
6e13e641 DB |
687 | /* for new style drivers, when registration returns the driver core |
688 | * will have called probe() for all matching-but-unbound devices. | |
689 | */ | |
1da177e4 LT |
690 | res = driver_register(&driver->driver); |
691 | if (res) | |
7eebcb7c | 692 | return res; |
438d6c2c | 693 | |
caada32a | 694 | mutex_lock(&core_lock); |
7eebcb7c | 695 | |
35d8b2e6 | 696 | pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name); |
1da177e4 | 697 | |
7b4fbc50 | 698 | /* legacy drivers scan i2c busses directly */ |
8a994755 | 699 | if (driver->attach_adapter) { |
4ad4eac6 DB |
700 | struct i2c_adapter *adapter; |
701 | ||
87c6c229 JD |
702 | down(&i2c_adapter_class.sem); |
703 | list_for_each_entry(adapter, &i2c_adapter_class.devices, | |
704 | dev.node) { | |
1da177e4 LT |
705 | driver->attach_adapter(adapter); |
706 | } | |
87c6c229 | 707 | up(&i2c_adapter_class.sem); |
1da177e4 LT |
708 | } |
709 | ||
caada32a | 710 | mutex_unlock(&core_lock); |
7eebcb7c | 711 | return 0; |
1da177e4 | 712 | } |
de59cf9e | 713 | EXPORT_SYMBOL(i2c_register_driver); |
1da177e4 | 714 | |
a1d9e6e4 DB |
715 | /** |
716 | * i2c_del_driver - unregister I2C driver | |
717 | * @driver: the driver being unregistered | |
d64f73be | 718 | * Context: can sleep |
a1d9e6e4 | 719 | */ |
b3e82096 | 720 | void i2c_del_driver(struct i2c_driver *driver) |
1da177e4 | 721 | { |
87c6c229 | 722 | struct list_head *item2, *_n; |
1da177e4 LT |
723 | struct i2c_client *client; |
724 | struct i2c_adapter *adap; | |
438d6c2c | 725 | |
caada32a | 726 | mutex_lock(&core_lock); |
1da177e4 | 727 | |
a1d9e6e4 DB |
728 | /* new-style driver? */ |
729 | if (is_newstyle_driver(driver)) | |
730 | goto unregister; | |
731 | ||
1da177e4 | 732 | /* Have a look at each adapter, if clients of this driver are still |
438d6c2c | 733 | * attached. If so, detach them to be able to kill the driver |
1da177e4 | 734 | * afterwards. |
1da177e4 | 735 | */ |
87c6c229 JD |
736 | down(&i2c_adapter_class.sem); |
737 | list_for_each_entry(adap, &i2c_adapter_class.devices, dev.node) { | |
1da177e4 | 738 | if (driver->detach_adapter) { |
b3e82096 | 739 | if (driver->detach_adapter(adap)) { |
b6d7b3d1 | 740 | dev_err(&adap->dev, "detach_adapter failed " |
35d8b2e6 LR |
741 | "for driver [%s]\n", |
742 | driver->driver.name); | |
1da177e4 LT |
743 | } |
744 | } else { | |
745 | list_for_each_safe(item2, _n, &adap->clients) { | |
746 | client = list_entry(item2, struct i2c_client, list); | |
747 | if (client->driver != driver) | |
748 | continue; | |
b6d7b3d1 JD |
749 | dev_dbg(&adap->dev, "detaching client [%s] " |
750 | "at 0x%02x\n", client->name, | |
751 | client->addr); | |
b3e82096 | 752 | if (driver->detach_client(client)) { |
b6d7b3d1 JD |
753 | dev_err(&adap->dev, "detach_client " |
754 | "failed for client [%s] at " | |
755 | "0x%02x\n", client->name, | |
1da177e4 | 756 | client->addr); |
1da177e4 LT |
757 | } |
758 | } | |
759 | } | |
760 | } | |
87c6c229 | 761 | up(&i2c_adapter_class.sem); |
1da177e4 | 762 | |
a1d9e6e4 | 763 | unregister: |
1da177e4 | 764 | driver_unregister(&driver->driver); |
35d8b2e6 | 765 | pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name); |
1da177e4 | 766 | |
caada32a | 767 | mutex_unlock(&core_lock); |
1da177e4 | 768 | } |
c0564606 | 769 | EXPORT_SYMBOL(i2c_del_driver); |
1da177e4 | 770 | |
7b4fbc50 DB |
771 | /* ------------------------------------------------------------------------- */ |
772 | ||
9b766b81 | 773 | static int __i2c_check_addr(struct device *dev, void *addrp) |
1da177e4 | 774 | { |
9b766b81 DB |
775 | struct i2c_client *client = i2c_verify_client(dev); |
776 | int addr = *(int *)addrp; | |
1da177e4 | 777 | |
9b766b81 DB |
778 | if (client && client->addr == addr) |
779 | return -EBUSY; | |
1da177e4 LT |
780 | return 0; |
781 | } | |
782 | ||
5e31c2bd | 783 | static int i2c_check_addr(struct i2c_adapter *adapter, int addr) |
1da177e4 | 784 | { |
9b766b81 | 785 | return device_for_each_child(&adapter->dev, &addr, __i2c_check_addr); |
1da177e4 LT |
786 | } |
787 | ||
788 | int i2c_attach_client(struct i2c_client *client) | |
789 | { | |
790 | struct i2c_adapter *adapter = client->adapter; | |
b119c6c9 | 791 | int res = 0; |
1da177e4 | 792 | |
1da177e4 | 793 | client->dev.parent = &client->adapter->dev; |
1da177e4 | 794 | client->dev.bus = &i2c_bus_type; |
9c1600ed DB |
795 | |
796 | if (client->driver) | |
797 | client->dev.driver = &client->driver->driver; | |
798 | ||
de81d2aa | 799 | if (client->driver && !is_newstyle_driver(client->driver)) { |
9c1600ed | 800 | client->dev.release = i2c_client_release; |
de81d2aa DB |
801 | client->dev.uevent_suppress = 1; |
802 | } else | |
9c1600ed | 803 | client->dev.release = i2c_client_dev_release; |
438d6c2c | 804 | |
1da177e4 LT |
805 | snprintf(&client->dev.bus_id[0], sizeof(client->dev.bus_id), |
806 | "%d-%04x", i2c_adapter_id(adapter), client->addr); | |
b119c6c9 JD |
807 | res = device_register(&client->dev); |
808 | if (res) | |
86ec5ec8 DB |
809 | goto out_err; |
810 | ||
811 | mutex_lock(&adapter->clist_lock); | |
812 | list_add_tail(&client->list, &adapter->clients); | |
b119c6c9 | 813 | mutex_unlock(&adapter->clist_lock); |
77ed74da | 814 | |
86ec5ec8 DB |
815 | dev_dbg(&adapter->dev, "client [%s] registered with bus id %s\n", |
816 | client->name, client->dev.bus_id); | |
817 | ||
77ed74da JD |
818 | if (adapter->client_register) { |
819 | if (adapter->client_register(client)) { | |
820 | dev_dbg(&adapter->dev, "client_register " | |
821 | "failed for client [%s] at 0x%02x\n", | |
822 | client->name, client->addr); | |
823 | } | |
824 | } | |
825 | ||
826 | return 0; | |
b119c6c9 | 827 | |
86ec5ec8 | 828 | out_err: |
b119c6c9 JD |
829 | dev_err(&adapter->dev, "Failed to attach i2c client %s at 0x%02x " |
830 | "(%d)\n", client->name, client->addr, res); | |
77ed74da | 831 | return res; |
1da177e4 | 832 | } |
c0564606 | 833 | EXPORT_SYMBOL(i2c_attach_client); |
1da177e4 LT |
834 | |
835 | int i2c_detach_client(struct i2c_client *client) | |
836 | { | |
837 | struct i2c_adapter *adapter = client->adapter; | |
838 | int res = 0; | |
438d6c2c | 839 | |
1da177e4 LT |
840 | if (adapter->client_unregister) { |
841 | res = adapter->client_unregister(client); | |
842 | if (res) { | |
843 | dev_err(&client->dev, | |
86749e85 JD |
844 | "client_unregister [%s] failed, " |
845 | "client not detached\n", client->name); | |
1da177e4 LT |
846 | goto out; |
847 | } | |
848 | } | |
849 | ||
5c085d36 | 850 | mutex_lock(&adapter->clist_lock); |
1da177e4 | 851 | list_del(&client->list); |
9ddced16 JD |
852 | mutex_unlock(&adapter->clist_lock); |
853 | ||
1da177e4 | 854 | init_completion(&client->released); |
1da177e4 | 855 | device_unregister(&client->dev); |
1da177e4 LT |
856 | wait_for_completion(&client->released); |
857 | ||
858 | out: | |
859 | return res; | |
860 | } | |
c0564606 | 861 | EXPORT_SYMBOL(i2c_detach_client); |
1da177e4 | 862 | |
e48d3319 JD |
863 | /** |
864 | * i2c_use_client - increments the reference count of the i2c client structure | |
865 | * @client: the client being referenced | |
866 | * | |
867 | * Each live reference to a client should be refcounted. The driver model does | |
868 | * that automatically as part of driver binding, so that most drivers don't | |
869 | * need to do this explicitly: they hold a reference until they're unbound | |
870 | * from the device. | |
871 | * | |
872 | * A pointer to the client with the incremented reference counter is returned. | |
873 | */ | |
874 | struct i2c_client *i2c_use_client(struct i2c_client *client) | |
1da177e4 | 875 | { |
bdc511f4 | 876 | get_device(&client->dev); |
e48d3319 | 877 | return client; |
1da177e4 | 878 | } |
c0564606 | 879 | EXPORT_SYMBOL(i2c_use_client); |
1da177e4 | 880 | |
e48d3319 JD |
881 | /** |
882 | * i2c_release_client - release a use of the i2c client structure | |
883 | * @client: the client being no longer referenced | |
884 | * | |
885 | * Must be called when a user of a client is finished with it. | |
886 | */ | |
887 | void i2c_release_client(struct i2c_client *client) | |
1da177e4 | 888 | { |
bdc511f4 | 889 | put_device(&client->dev); |
1da177e4 | 890 | } |
c0564606 | 891 | EXPORT_SYMBOL(i2c_release_client); |
1da177e4 | 892 | |
9b766b81 DB |
893 | struct i2c_cmd_arg { |
894 | unsigned cmd; | |
895 | void *arg; | |
896 | }; | |
897 | ||
898 | static int i2c_cmd(struct device *dev, void *_arg) | |
899 | { | |
900 | struct i2c_client *client = i2c_verify_client(dev); | |
901 | struct i2c_cmd_arg *arg = _arg; | |
902 | ||
903 | if (client && client->driver && client->driver->command) | |
904 | client->driver->command(client, arg->cmd, arg->arg); | |
905 | return 0; | |
906 | } | |
907 | ||
1da177e4 LT |
908 | void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg) |
909 | { | |
9b766b81 | 910 | struct i2c_cmd_arg cmd_arg; |
1da177e4 | 911 | |
9b766b81 DB |
912 | cmd_arg.cmd = cmd; |
913 | cmd_arg.arg = arg; | |
914 | device_for_each_child(&adap->dev, &cmd_arg, i2c_cmd); | |
1da177e4 | 915 | } |
c0564606 | 916 | EXPORT_SYMBOL(i2c_clients_command); |
1da177e4 LT |
917 | |
918 | static int __init i2c_init(void) | |
919 | { | |
920 | int retval; | |
921 | ||
922 | retval = bus_register(&i2c_bus_type); | |
1da177e4 LT |
923 | if (retval) |
924 | return retval; | |
e9f1373b DB |
925 | retval = class_register(&i2c_adapter_class); |
926 | if (retval) | |
927 | goto bus_err; | |
928 | retval = i2c_add_driver(&dummy_driver); | |
929 | if (retval) | |
930 | goto class_err; | |
931 | return 0; | |
932 | ||
933 | class_err: | |
934 | class_unregister(&i2c_adapter_class); | |
935 | bus_err: | |
936 | bus_unregister(&i2c_bus_type); | |
937 | return retval; | |
1da177e4 LT |
938 | } |
939 | ||
940 | static void __exit i2c_exit(void) | |
941 | { | |
e9f1373b | 942 | i2c_del_driver(&dummy_driver); |
1da177e4 | 943 | class_unregister(&i2c_adapter_class); |
1da177e4 LT |
944 | bus_unregister(&i2c_bus_type); |
945 | } | |
946 | ||
947 | subsys_initcall(i2c_init); | |
948 | module_exit(i2c_exit); | |
949 | ||
950 | /* ---------------------------------------------------- | |
951 | * the functional interface to the i2c busses. | |
952 | * ---------------------------------------------------- | |
953 | */ | |
954 | ||
955 | int i2c_transfer(struct i2c_adapter * adap, struct i2c_msg *msgs, int num) | |
956 | { | |
957 | int ret; | |
958 | ||
959 | if (adap->algo->master_xfer) { | |
960 | #ifdef DEBUG | |
961 | for (ret = 0; ret < num; ret++) { | |
962 | dev_dbg(&adap->dev, "master_xfer[%d] %c, addr=0x%02x, " | |
209d27c3 JD |
963 | "len=%d%s\n", ret, (msgs[ret].flags & I2C_M_RD) |
964 | ? 'R' : 'W', msgs[ret].addr, msgs[ret].len, | |
965 | (msgs[ret].flags & I2C_M_RECV_LEN) ? "+" : ""); | |
1da177e4 LT |
966 | } |
967 | #endif | |
968 | ||
cea443a8 MR |
969 | if (in_atomic() || irqs_disabled()) { |
970 | ret = mutex_trylock(&adap->bus_lock); | |
971 | if (!ret) | |
972 | /* I2C activity is ongoing. */ | |
973 | return -EAGAIN; | |
974 | } else { | |
975 | mutex_lock_nested(&adap->bus_lock, adap->level); | |
976 | } | |
977 | ||
1da177e4 | 978 | ret = adap->algo->master_xfer(adap,msgs,num); |
5c085d36 | 979 | mutex_unlock(&adap->bus_lock); |
1da177e4 LT |
980 | |
981 | return ret; | |
982 | } else { | |
983 | dev_dbg(&adap->dev, "I2C level transfers not supported\n"); | |
984 | return -ENOSYS; | |
985 | } | |
986 | } | |
c0564606 | 987 | EXPORT_SYMBOL(i2c_transfer); |
1da177e4 LT |
988 | |
989 | int i2c_master_send(struct i2c_client *client,const char *buf ,int count) | |
990 | { | |
991 | int ret; | |
992 | struct i2c_adapter *adap=client->adapter; | |
993 | struct i2c_msg msg; | |
994 | ||
815f55f2 JD |
995 | msg.addr = client->addr; |
996 | msg.flags = client->flags & I2C_M_TEN; | |
997 | msg.len = count; | |
998 | msg.buf = (char *)buf; | |
438d6c2c | 999 | |
815f55f2 | 1000 | ret = i2c_transfer(adap, &msg, 1); |
1da177e4 | 1001 | |
815f55f2 JD |
1002 | /* If everything went ok (i.e. 1 msg transmitted), return #bytes |
1003 | transmitted, else error code. */ | |
1004 | return (ret == 1) ? count : ret; | |
1da177e4 | 1005 | } |
c0564606 | 1006 | EXPORT_SYMBOL(i2c_master_send); |
1da177e4 LT |
1007 | |
1008 | int i2c_master_recv(struct i2c_client *client, char *buf ,int count) | |
1009 | { | |
1010 | struct i2c_adapter *adap=client->adapter; | |
1011 | struct i2c_msg msg; | |
1012 | int ret; | |
815f55f2 JD |
1013 | |
1014 | msg.addr = client->addr; | |
1015 | msg.flags = client->flags & I2C_M_TEN; | |
1016 | msg.flags |= I2C_M_RD; | |
1017 | msg.len = count; | |
1018 | msg.buf = buf; | |
1019 | ||
1020 | ret = i2c_transfer(adap, &msg, 1); | |
1021 | ||
1022 | /* If everything went ok (i.e. 1 msg transmitted), return #bytes | |
1023 | transmitted, else error code. */ | |
1024 | return (ret == 1) ? count : ret; | |
1da177e4 | 1025 | } |
c0564606 | 1026 | EXPORT_SYMBOL(i2c_master_recv); |
1da177e4 | 1027 | |
1da177e4 LT |
1028 | /* ---------------------------------------------------- |
1029 | * the i2c address scanning function | |
1030 | * Will not work for 10-bit addresses! | |
1031 | * ---------------------------------------------------- | |
1032 | */ | |
a89ba0bc JD |
1033 | static int i2c_probe_address(struct i2c_adapter *adapter, int addr, int kind, |
1034 | int (*found_proc) (struct i2c_adapter *, int, int)) | |
1035 | { | |
1036 | int err; | |
1037 | ||
1038 | /* Make sure the address is valid */ | |
1039 | if (addr < 0x03 || addr > 0x77) { | |
1040 | dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n", | |
1041 | addr); | |
1042 | return -EINVAL; | |
9fc6adfa JD |
1043 | } |
1044 | ||
a89ba0bc JD |
1045 | /* Skip if already in use */ |
1046 | if (i2c_check_addr(adapter, addr)) | |
1047 | return 0; | |
1048 | ||
1049 | /* Make sure there is something at this address, unless forced */ | |
4c9337da JD |
1050 | if (kind < 0) { |
1051 | if (i2c_smbus_xfer(adapter, addr, 0, 0, 0, | |
1052 | I2C_SMBUS_QUICK, NULL) < 0) | |
1053 | return 0; | |
1054 | ||
1055 | /* prevent 24RF08 corruption */ | |
1056 | if ((addr & ~0x0f) == 0x50) | |
1057 | i2c_smbus_xfer(adapter, addr, 0, 0, 0, | |
1058 | I2C_SMBUS_QUICK, NULL); | |
1059 | } | |
a89ba0bc JD |
1060 | |
1061 | /* Finally call the custom detection function */ | |
1062 | err = found_proc(adapter, addr, kind); | |
a89ba0bc JD |
1063 | /* -ENODEV can be returned if there is a chip at the given address |
1064 | but it isn't supported by this chip driver. We catch it here as | |
1065 | this isn't an error. */ | |
114fd183 JD |
1066 | if (err == -ENODEV) |
1067 | err = 0; | |
1068 | ||
1069 | if (err) | |
1070 | dev_warn(&adapter->dev, "Client creation failed at 0x%x (%d)\n", | |
1071 | addr, err); | |
1072 | return err; | |
9fc6adfa JD |
1073 | } |
1074 | ||
1da177e4 | 1075 | int i2c_probe(struct i2c_adapter *adapter, |
bfb6df24 | 1076 | const struct i2c_client_address_data *address_data, |
1da177e4 LT |
1077 | int (*found_proc) (struct i2c_adapter *, int, int)) |
1078 | { | |
a89ba0bc | 1079 | int i, err; |
1da177e4 LT |
1080 | int adap_id = i2c_adapter_id(adapter); |
1081 | ||
a89ba0bc JD |
1082 | /* Force entries are done first, and are not affected by ignore |
1083 | entries */ | |
1084 | if (address_data->forces) { | |
bfb6df24 | 1085 | const unsigned short * const *forces = address_data->forces; |
a89ba0bc JD |
1086 | int kind; |
1087 | ||
1088 | for (kind = 0; forces[kind]; kind++) { | |
1089 | for (i = 0; forces[kind][i] != I2C_CLIENT_END; | |
1090 | i += 2) { | |
1091 | if (forces[kind][i] == adap_id | |
1092 | || forces[kind][i] == ANY_I2C_BUS) { | |
1093 | dev_dbg(&adapter->dev, "found force " | |
1094 | "parameter for adapter %d, " | |
1095 | "addr 0x%02x, kind %d\n", | |
1096 | adap_id, forces[kind][i + 1], | |
1097 | kind); | |
1098 | err = i2c_probe_address(adapter, | |
1099 | forces[kind][i + 1], | |
1100 | kind, found_proc); | |
1101 | if (err) | |
1102 | return err; | |
1103 | } | |
1da177e4 LT |
1104 | } |
1105 | } | |
a89ba0bc | 1106 | } |
1da177e4 | 1107 | |
4366dc94 JD |
1108 | /* Stop here if we can't use SMBUS_QUICK */ |
1109 | if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_QUICK)) { | |
1110 | if (address_data->probe[0] == I2C_CLIENT_END | |
1111 | && address_data->normal_i2c[0] == I2C_CLIENT_END) | |
438d6c2c | 1112 | return 0; |
4366dc94 JD |
1113 | |
1114 | dev_warn(&adapter->dev, "SMBus Quick command not supported, " | |
1115 | "can't probe for chips\n"); | |
1116 | return -1; | |
1117 | } | |
1118 | ||
a89ba0bc JD |
1119 | /* Probe entries are done second, and are not affected by ignore |
1120 | entries either */ | |
1121 | for (i = 0; address_data->probe[i] != I2C_CLIENT_END; i += 2) { | |
1122 | if (address_data->probe[i] == adap_id | |
1123 | || address_data->probe[i] == ANY_I2C_BUS) { | |
1124 | dev_dbg(&adapter->dev, "found probe parameter for " | |
1125 | "adapter %d, addr 0x%02x\n", adap_id, | |
1126 | address_data->probe[i + 1]); | |
1127 | err = i2c_probe_address(adapter, | |
1128 | address_data->probe[i + 1], | |
1129 | -1, found_proc); | |
1130 | if (err) | |
1131 | return err; | |
1da177e4 | 1132 | } |
a89ba0bc | 1133 | } |
1da177e4 | 1134 | |
a89ba0bc JD |
1135 | /* Normal entries are done last, unless shadowed by an ignore entry */ |
1136 | for (i = 0; address_data->normal_i2c[i] != I2C_CLIENT_END; i += 1) { | |
1137 | int j, ignore; | |
1138 | ||
1139 | ignore = 0; | |
1140 | for (j = 0; address_data->ignore[j] != I2C_CLIENT_END; | |
1141 | j += 2) { | |
1142 | if ((address_data->ignore[j] == adap_id || | |
1143 | address_data->ignore[j] == ANY_I2C_BUS) | |
1144 | && address_data->ignore[j + 1] | |
1145 | == address_data->normal_i2c[i]) { | |
1146 | dev_dbg(&adapter->dev, "found ignore " | |
1147 | "parameter for adapter %d, " | |
1148 | "addr 0x%02x\n", adap_id, | |
1149 | address_data->ignore[j + 1]); | |
2369df93 MH |
1150 | ignore = 1; |
1151 | break; | |
1da177e4 LT |
1152 | } |
1153 | } | |
a89ba0bc | 1154 | if (ignore) |
1da177e4 LT |
1155 | continue; |
1156 | ||
a89ba0bc JD |
1157 | dev_dbg(&adapter->dev, "found normal entry for adapter %d, " |
1158 | "addr 0x%02x\n", adap_id, | |
1159 | address_data->normal_i2c[i]); | |
1160 | err = i2c_probe_address(adapter, address_data->normal_i2c[i], | |
1161 | -1, found_proc); | |
1162 | if (err) | |
1163 | return err; | |
1da177e4 | 1164 | } |
a89ba0bc | 1165 | |
1da177e4 LT |
1166 | return 0; |
1167 | } | |
c0564606 | 1168 | EXPORT_SYMBOL(i2c_probe); |
1da177e4 | 1169 | |
12b5053a JD |
1170 | struct i2c_client * |
1171 | i2c_new_probed_device(struct i2c_adapter *adap, | |
1172 | struct i2c_board_info *info, | |
1173 | unsigned short const *addr_list) | |
1174 | { | |
1175 | int i; | |
1176 | ||
1177 | /* Stop here if the bus doesn't support probing */ | |
1178 | if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) { | |
1179 | dev_err(&adap->dev, "Probing not supported\n"); | |
1180 | return NULL; | |
1181 | } | |
1182 | ||
12b5053a JD |
1183 | for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { |
1184 | /* Check address validity */ | |
1185 | if (addr_list[i] < 0x03 || addr_list[i] > 0x77) { | |
1186 | dev_warn(&adap->dev, "Invalid 7-bit address " | |
1187 | "0x%02x\n", addr_list[i]); | |
1188 | continue; | |
1189 | } | |
1190 | ||
1191 | /* Check address availability */ | |
9b766b81 | 1192 | if (i2c_check_addr(adap, addr_list[i])) { |
12b5053a JD |
1193 | dev_dbg(&adap->dev, "Address 0x%02x already in " |
1194 | "use, not probing\n", addr_list[i]); | |
1195 | continue; | |
1196 | } | |
1197 | ||
1198 | /* Test address responsiveness | |
1199 | The default probe method is a quick write, but it is known | |
1200 | to corrupt the 24RF08 EEPROMs due to a state machine bug, | |
1201 | and could also irreversibly write-protect some EEPROMs, so | |
1202 | for address ranges 0x30-0x37 and 0x50-0x5f, we use a byte | |
1203 | read instead. Also, some bus drivers don't implement | |
1204 | quick write, so we fallback to a byte read it that case | |
1205 | too. */ | |
1206 | if ((addr_list[i] & ~0x07) == 0x30 | |
1207 | || (addr_list[i] & ~0x0f) == 0x50 | |
1208 | || !i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) { | |
1209 | if (i2c_smbus_xfer(adap, addr_list[i], 0, | |
1210 | I2C_SMBUS_READ, 0, | |
1211 | I2C_SMBUS_BYTE, NULL) >= 0) | |
1212 | break; | |
1213 | } else { | |
1214 | if (i2c_smbus_xfer(adap, addr_list[i], 0, | |
1215 | I2C_SMBUS_WRITE, 0, | |
1216 | I2C_SMBUS_QUICK, NULL) >= 0) | |
1217 | break; | |
1218 | } | |
1219 | } | |
12b5053a JD |
1220 | |
1221 | if (addr_list[i] == I2C_CLIENT_END) { | |
1222 | dev_dbg(&adap->dev, "Probing failed, no device found\n"); | |
1223 | return NULL; | |
1224 | } | |
1225 | ||
1226 | info->addr = addr_list[i]; | |
1227 | return i2c_new_device(adap, info); | |
1228 | } | |
1229 | EXPORT_SYMBOL_GPL(i2c_new_probed_device); | |
1230 | ||
1da177e4 LT |
1231 | struct i2c_adapter* i2c_get_adapter(int id) |
1232 | { | |
1da177e4 | 1233 | struct i2c_adapter *adapter; |
438d6c2c | 1234 | |
caada32a | 1235 | mutex_lock(&core_lock); |
a0920e10 MH |
1236 | adapter = (struct i2c_adapter *)idr_find(&i2c_adapter_idr, id); |
1237 | if (adapter && !try_module_get(adapter->owner)) | |
1238 | adapter = NULL; | |
1239 | ||
caada32a | 1240 | mutex_unlock(&core_lock); |
a0920e10 | 1241 | return adapter; |
1da177e4 | 1242 | } |
c0564606 | 1243 | EXPORT_SYMBOL(i2c_get_adapter); |
1da177e4 LT |
1244 | |
1245 | void i2c_put_adapter(struct i2c_adapter *adap) | |
1246 | { | |
1247 | module_put(adap->owner); | |
1248 | } | |
c0564606 | 1249 | EXPORT_SYMBOL(i2c_put_adapter); |
1da177e4 LT |
1250 | |
1251 | /* The SMBus parts */ | |
1252 | ||
438d6c2c | 1253 | #define POLY (0x1070U << 3) |
1da177e4 LT |
1254 | static u8 |
1255 | crc8(u16 data) | |
1256 | { | |
1257 | int i; | |
438d6c2c | 1258 | |
1da177e4 | 1259 | for(i = 0; i < 8; i++) { |
438d6c2c | 1260 | if (data & 0x8000) |
1da177e4 LT |
1261 | data = data ^ POLY; |
1262 | data = data << 1; | |
1263 | } | |
1264 | return (u8)(data >> 8); | |
1265 | } | |
1266 | ||
421ef47b JD |
1267 | /* Incremental CRC8 over count bytes in the array pointed to by p */ |
1268 | static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count) | |
1da177e4 LT |
1269 | { |
1270 | int i; | |
1271 | ||
1272 | for(i = 0; i < count; i++) | |
421ef47b | 1273 | crc = crc8((crc ^ p[i]) << 8); |
1da177e4 LT |
1274 | return crc; |
1275 | } | |
1276 | ||
421ef47b JD |
1277 | /* Assume a 7-bit address, which is reasonable for SMBus */ |
1278 | static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg) | |
1da177e4 | 1279 | { |
421ef47b JD |
1280 | /* The address will be sent first */ |
1281 | u8 addr = (msg->addr << 1) | !!(msg->flags & I2C_M_RD); | |
1282 | pec = i2c_smbus_pec(pec, &addr, 1); | |
1283 | ||
1284 | /* The data buffer follows */ | |
1285 | return i2c_smbus_pec(pec, msg->buf, msg->len); | |
1da177e4 LT |
1286 | } |
1287 | ||
421ef47b JD |
1288 | /* Used for write only transactions */ |
1289 | static inline void i2c_smbus_add_pec(struct i2c_msg *msg) | |
1da177e4 | 1290 | { |
421ef47b JD |
1291 | msg->buf[msg->len] = i2c_smbus_msg_pec(0, msg); |
1292 | msg->len++; | |
1da177e4 LT |
1293 | } |
1294 | ||
421ef47b JD |
1295 | /* Return <0 on CRC error |
1296 | If there was a write before this read (most cases) we need to take the | |
1297 | partial CRC from the write part into account. | |
1298 | Note that this function does modify the message (we need to decrease the | |
1299 | message length to hide the CRC byte from the caller). */ | |
1300 | static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg) | |
1da177e4 | 1301 | { |
421ef47b JD |
1302 | u8 rpec = msg->buf[--msg->len]; |
1303 | cpec = i2c_smbus_msg_pec(cpec, msg); | |
1da177e4 | 1304 | |
1da177e4 LT |
1305 | if (rpec != cpec) { |
1306 | pr_debug("i2c-core: Bad PEC 0x%02x vs. 0x%02x\n", | |
1307 | rpec, cpec); | |
1308 | return -1; | |
1309 | } | |
438d6c2c | 1310 | return 0; |
1da177e4 LT |
1311 | } |
1312 | ||
1313 | s32 i2c_smbus_write_quick(struct i2c_client *client, u8 value) | |
1314 | { | |
1315 | return i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
438d6c2c | 1316 | value,0,I2C_SMBUS_QUICK,NULL); |
1da177e4 | 1317 | } |
c0564606 | 1318 | EXPORT_SYMBOL(i2c_smbus_write_quick); |
1da177e4 LT |
1319 | |
1320 | s32 i2c_smbus_read_byte(struct i2c_client *client) | |
1321 | { | |
1322 | union i2c_smbus_data data; | |
1323 | if (i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
1324 | I2C_SMBUS_READ,0,I2C_SMBUS_BYTE, &data)) | |
1325 | return -1; | |
1326 | else | |
7eff82c8 | 1327 | return data.byte; |
1da177e4 | 1328 | } |
c0564606 | 1329 | EXPORT_SYMBOL(i2c_smbus_read_byte); |
1da177e4 LT |
1330 | |
1331 | s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value) | |
1332 | { | |
1da177e4 | 1333 | return i2c_smbus_xfer(client->adapter,client->addr,client->flags, |
421ef47b | 1334 | I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL); |
1da177e4 | 1335 | } |
c0564606 | 1336 | EXPORT_SYMBOL(i2c_smbus_write_byte); |
1da177e4 LT |
1337 | |
1338 | s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command) | |
1339 | { | |
1340 | union i2c_smbus_data data; | |
1341 | if (i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
1342 | I2C_SMBUS_READ,command, I2C_SMBUS_BYTE_DATA,&data)) | |
1343 | return -1; | |
1344 | else | |
7eff82c8 | 1345 | return data.byte; |
1da177e4 | 1346 | } |
c0564606 | 1347 | EXPORT_SYMBOL(i2c_smbus_read_byte_data); |
1da177e4 LT |
1348 | |
1349 | s32 i2c_smbus_write_byte_data(struct i2c_client *client, u8 command, u8 value) | |
1350 | { | |
1351 | union i2c_smbus_data data; | |
1352 | data.byte = value; | |
1353 | return i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
1354 | I2C_SMBUS_WRITE,command, | |
1355 | I2C_SMBUS_BYTE_DATA,&data); | |
1356 | } | |
c0564606 | 1357 | EXPORT_SYMBOL(i2c_smbus_write_byte_data); |
1da177e4 LT |
1358 | |
1359 | s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command) | |
1360 | { | |
1361 | union i2c_smbus_data data; | |
1362 | if (i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
1363 | I2C_SMBUS_READ,command, I2C_SMBUS_WORD_DATA, &data)) | |
1364 | return -1; | |
1365 | else | |
7eff82c8 | 1366 | return data.word; |
1da177e4 | 1367 | } |
c0564606 | 1368 | EXPORT_SYMBOL(i2c_smbus_read_word_data); |
1da177e4 LT |
1369 | |
1370 | s32 i2c_smbus_write_word_data(struct i2c_client *client, u8 command, u16 value) | |
1371 | { | |
1372 | union i2c_smbus_data data; | |
1373 | data.word = value; | |
1374 | return i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
1375 | I2C_SMBUS_WRITE,command, | |
1376 | I2C_SMBUS_WORD_DATA,&data); | |
1377 | } | |
c0564606 | 1378 | EXPORT_SYMBOL(i2c_smbus_write_word_data); |
1da177e4 | 1379 | |
a64ec07d DB |
1380 | /** |
1381 | * i2c_smbus_read_block_data - SMBus block read request | |
1382 | * @client: Handle to slave device | |
1383 | * @command: Command byte issued to let the slave know what data should | |
1384 | * be returned | |
1385 | * @values: Byte array into which data will be read; big enough to hold | |
1386 | * the data returned by the slave. SMBus allows at most 32 bytes. | |
1387 | * | |
1388 | * Returns the number of bytes read in the slave's response, else a | |
1389 | * negative number to indicate some kind of error. | |
1390 | * | |
1391 | * Note that using this function requires that the client's adapter support | |
1392 | * the I2C_FUNC_SMBUS_READ_BLOCK_DATA functionality. Not all adapter drivers | |
1393 | * support this; its emulation through I2C messaging relies on a specific | |
1394 | * mechanism (I2C_M_RECV_LEN) which may not be implemented. | |
1395 | */ | |
b86a1bc8 JD |
1396 | s32 i2c_smbus_read_block_data(struct i2c_client *client, u8 command, |
1397 | u8 *values) | |
1398 | { | |
1399 | union i2c_smbus_data data; | |
1400 | ||
1401 | if (i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1402 | I2C_SMBUS_READ, command, | |
1403 | I2C_SMBUS_BLOCK_DATA, &data)) | |
1404 | return -1; | |
1405 | ||
1406 | memcpy(values, &data.block[1], data.block[0]); | |
1407 | return data.block[0]; | |
1408 | } | |
1409 | EXPORT_SYMBOL(i2c_smbus_read_block_data); | |
1410 | ||
1da177e4 | 1411 | s32 i2c_smbus_write_block_data(struct i2c_client *client, u8 command, |
46f5ed75 | 1412 | u8 length, const u8 *values) |
1da177e4 LT |
1413 | { |
1414 | union i2c_smbus_data data; | |
7656032b | 1415 | |
1da177e4 LT |
1416 | if (length > I2C_SMBUS_BLOCK_MAX) |
1417 | length = I2C_SMBUS_BLOCK_MAX; | |
1da177e4 | 1418 | data.block[0] = length; |
7656032b | 1419 | memcpy(&data.block[1], values, length); |
1da177e4 LT |
1420 | return i2c_smbus_xfer(client->adapter,client->addr,client->flags, |
1421 | I2C_SMBUS_WRITE,command, | |
1422 | I2C_SMBUS_BLOCK_DATA,&data); | |
1423 | } | |
c0564606 | 1424 | EXPORT_SYMBOL(i2c_smbus_write_block_data); |
1da177e4 LT |
1425 | |
1426 | /* Returns the number of read bytes */ | |
4b2643d7 JD |
1427 | s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client, u8 command, |
1428 | u8 length, u8 *values) | |
1da177e4 LT |
1429 | { |
1430 | union i2c_smbus_data data; | |
7656032b | 1431 | |
4b2643d7 JD |
1432 | if (length > I2C_SMBUS_BLOCK_MAX) |
1433 | length = I2C_SMBUS_BLOCK_MAX; | |
1434 | data.block[0] = length; | |
1da177e4 LT |
1435 | if (i2c_smbus_xfer(client->adapter,client->addr,client->flags, |
1436 | I2C_SMBUS_READ,command, | |
1437 | I2C_SMBUS_I2C_BLOCK_DATA,&data)) | |
1438 | return -1; | |
7656032b JD |
1439 | |
1440 | memcpy(values, &data.block[1], data.block[0]); | |
1441 | return data.block[0]; | |
1da177e4 | 1442 | } |
c0564606 | 1443 | EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data); |
1da177e4 | 1444 | |
21bbd691 | 1445 | s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client, u8 command, |
46f5ed75 | 1446 | u8 length, const u8 *values) |
21bbd691 JD |
1447 | { |
1448 | union i2c_smbus_data data; | |
1449 | ||
1450 | if (length > I2C_SMBUS_BLOCK_MAX) | |
1451 | length = I2C_SMBUS_BLOCK_MAX; | |
1452 | data.block[0] = length; | |
1453 | memcpy(data.block + 1, values, length); | |
1454 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1455 | I2C_SMBUS_WRITE, command, | |
1456 | I2C_SMBUS_I2C_BLOCK_DATA, &data); | |
1457 | } | |
c0564606 | 1458 | EXPORT_SYMBOL(i2c_smbus_write_i2c_block_data); |
21bbd691 | 1459 | |
438d6c2c | 1460 | /* Simulate a SMBus command using the i2c protocol |
1da177e4 | 1461 | No checking of parameters is done! */ |
438d6c2c | 1462 | static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr, |
1da177e4 | 1463 | unsigned short flags, |
438d6c2c | 1464 | char read_write, u8 command, int size, |
1da177e4 LT |
1465 | union i2c_smbus_data * data) |
1466 | { | |
1467 | /* So we need to generate a series of msgs. In the case of writing, we | |
1468 | need to use only one message; when reading, we need two. We initialize | |
1469 | most things with sane defaults, to keep the code below somewhat | |
1470 | simpler. */ | |
5c50d188 HI |
1471 | unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3]; |
1472 | unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2]; | |
1da177e4 | 1473 | int num = read_write == I2C_SMBUS_READ?2:1; |
438d6c2c | 1474 | struct i2c_msg msg[2] = { { addr, flags, 1, msgbuf0 }, |
1da177e4 LT |
1475 | { addr, flags | I2C_M_RD, 0, msgbuf1 } |
1476 | }; | |
1477 | int i; | |
421ef47b | 1478 | u8 partial_pec = 0; |
1da177e4 LT |
1479 | |
1480 | msgbuf0[0] = command; | |
1481 | switch(size) { | |
1482 | case I2C_SMBUS_QUICK: | |
1483 | msg[0].len = 0; | |
1484 | /* Special case: The read/write field is used as data */ | |
1485 | msg[0].flags = flags | (read_write==I2C_SMBUS_READ)?I2C_M_RD:0; | |
1486 | num = 1; | |
1487 | break; | |
1488 | case I2C_SMBUS_BYTE: | |
1489 | if (read_write == I2C_SMBUS_READ) { | |
1490 | /* Special case: only a read! */ | |
1491 | msg[0].flags = I2C_M_RD | flags; | |
1492 | num = 1; | |
1493 | } | |
1494 | break; | |
1495 | case I2C_SMBUS_BYTE_DATA: | |
1496 | if (read_write == I2C_SMBUS_READ) | |
1497 | msg[1].len = 1; | |
1498 | else { | |
1499 | msg[0].len = 2; | |
1500 | msgbuf0[1] = data->byte; | |
1501 | } | |
1502 | break; | |
1503 | case I2C_SMBUS_WORD_DATA: | |
1504 | if (read_write == I2C_SMBUS_READ) | |
1505 | msg[1].len = 2; | |
1506 | else { | |
1507 | msg[0].len=3; | |
1508 | msgbuf0[1] = data->word & 0xff; | |
7eff82c8 | 1509 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
1510 | } |
1511 | break; | |
1512 | case I2C_SMBUS_PROC_CALL: | |
1513 | num = 2; /* Special case */ | |
1514 | read_write = I2C_SMBUS_READ; | |
1515 | msg[0].len = 3; | |
1516 | msg[1].len = 2; | |
1517 | msgbuf0[1] = data->word & 0xff; | |
7eff82c8 | 1518 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
1519 | break; |
1520 | case I2C_SMBUS_BLOCK_DATA: | |
1da177e4 | 1521 | if (read_write == I2C_SMBUS_READ) { |
209d27c3 JD |
1522 | msg[1].flags |= I2C_M_RECV_LEN; |
1523 | msg[1].len = 1; /* block length will be added by | |
1524 | the underlying bus driver */ | |
1da177e4 LT |
1525 | } else { |
1526 | msg[0].len = data->block[0] + 2; | |
1527 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 2) { | |
1528 | dev_err(&adapter->dev, "smbus_access called with " | |
1529 | "invalid block write size (%d)\n", | |
1530 | data->block[0]); | |
1531 | return -1; | |
1532 | } | |
5c50d188 | 1533 | for (i = 1; i < msg[0].len; i++) |
1da177e4 LT |
1534 | msgbuf0[i] = data->block[i-1]; |
1535 | } | |
1536 | break; | |
1537 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
209d27c3 JD |
1538 | num = 2; /* Another special case */ |
1539 | read_write = I2C_SMBUS_READ; | |
1540 | if (data->block[0] > I2C_SMBUS_BLOCK_MAX) { | |
1541 | dev_err(&adapter->dev, "%s called with invalid " | |
08882d20 | 1542 | "block proc call size (%d)\n", __func__, |
209d27c3 JD |
1543 | data->block[0]); |
1544 | return -1; | |
1545 | } | |
1546 | msg[0].len = data->block[0] + 2; | |
1547 | for (i = 1; i < msg[0].len; i++) | |
1548 | msgbuf0[i] = data->block[i-1]; | |
1549 | msg[1].flags |= I2C_M_RECV_LEN; | |
1550 | msg[1].len = 1; /* block length will be added by | |
1551 | the underlying bus driver */ | |
1552 | break; | |
1da177e4 LT |
1553 | case I2C_SMBUS_I2C_BLOCK_DATA: |
1554 | if (read_write == I2C_SMBUS_READ) { | |
4b2643d7 | 1555 | msg[1].len = data->block[0]; |
1da177e4 LT |
1556 | } else { |
1557 | msg[0].len = data->block[0] + 1; | |
30dac746 | 1558 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 1) { |
1da177e4 LT |
1559 | dev_err(&adapter->dev, "i2c_smbus_xfer_emulated called with " |
1560 | "invalid block write size (%d)\n", | |
1561 | data->block[0]); | |
1562 | return -1; | |
1563 | } | |
1564 | for (i = 1; i <= data->block[0]; i++) | |
1565 | msgbuf0[i] = data->block[i]; | |
1566 | } | |
1567 | break; | |
1568 | default: | |
1569 | dev_err(&adapter->dev, "smbus_access called with invalid size (%d)\n", | |
1570 | size); | |
1571 | return -1; | |
1572 | } | |
1573 | ||
421ef47b JD |
1574 | i = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK |
1575 | && size != I2C_SMBUS_I2C_BLOCK_DATA); | |
1576 | if (i) { | |
1577 | /* Compute PEC if first message is a write */ | |
1578 | if (!(msg[0].flags & I2C_M_RD)) { | |
438d6c2c | 1579 | if (num == 1) /* Write only */ |
421ef47b JD |
1580 | i2c_smbus_add_pec(&msg[0]); |
1581 | else /* Write followed by read */ | |
1582 | partial_pec = i2c_smbus_msg_pec(0, &msg[0]); | |
1583 | } | |
1584 | /* Ask for PEC if last message is a read */ | |
1585 | if (msg[num-1].flags & I2C_M_RD) | |
438d6c2c | 1586 | msg[num-1].len++; |
421ef47b JD |
1587 | } |
1588 | ||
1da177e4 LT |
1589 | if (i2c_transfer(adapter, msg, num) < 0) |
1590 | return -1; | |
1591 | ||
421ef47b JD |
1592 | /* Check PEC if last message is a read */ |
1593 | if (i && (msg[num-1].flags & I2C_M_RD)) { | |
1594 | if (i2c_smbus_check_pec(partial_pec, &msg[num-1]) < 0) | |
1595 | return -1; | |
1596 | } | |
1597 | ||
1da177e4 LT |
1598 | if (read_write == I2C_SMBUS_READ) |
1599 | switch(size) { | |
1600 | case I2C_SMBUS_BYTE: | |
1601 | data->byte = msgbuf0[0]; | |
1602 | break; | |
1603 | case I2C_SMBUS_BYTE_DATA: | |
1604 | data->byte = msgbuf1[0]; | |
1605 | break; | |
438d6c2c | 1606 | case I2C_SMBUS_WORD_DATA: |
1da177e4 LT |
1607 | case I2C_SMBUS_PROC_CALL: |
1608 | data->word = msgbuf1[0] | (msgbuf1[1] << 8); | |
1609 | break; | |
1610 | case I2C_SMBUS_I2C_BLOCK_DATA: | |
4b2643d7 | 1611 | for (i = 0; i < data->block[0]; i++) |
1da177e4 LT |
1612 | data->block[i+1] = msgbuf1[i]; |
1613 | break; | |
209d27c3 JD |
1614 | case I2C_SMBUS_BLOCK_DATA: |
1615 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
1616 | for (i = 0; i < msgbuf1[0] + 1; i++) | |
1617 | data->block[i] = msgbuf1[i]; | |
1618 | break; | |
1da177e4 LT |
1619 | } |
1620 | return 0; | |
1621 | } | |
1622 | ||
1623 | ||
1624 | s32 i2c_smbus_xfer(struct i2c_adapter * adapter, u16 addr, unsigned short flags, | |
438d6c2c | 1625 | char read_write, u8 command, int size, |
1da177e4 LT |
1626 | union i2c_smbus_data * data) |
1627 | { | |
1628 | s32 res; | |
1da177e4 LT |
1629 | |
1630 | flags &= I2C_M_TEN | I2C_CLIENT_PEC; | |
1da177e4 LT |
1631 | |
1632 | if (adapter->algo->smbus_xfer) { | |
5c085d36 | 1633 | mutex_lock(&adapter->bus_lock); |
1da177e4 LT |
1634 | res = adapter->algo->smbus_xfer(adapter,addr,flags,read_write, |
1635 | command,size,data); | |
5c085d36 | 1636 | mutex_unlock(&adapter->bus_lock); |
1da177e4 LT |
1637 | } else |
1638 | res = i2c_smbus_xfer_emulated(adapter,addr,flags,read_write, | |
1639 | command,size,data); | |
1640 | ||
1da177e4 LT |
1641 | return res; |
1642 | } | |
1da177e4 | 1643 | EXPORT_SYMBOL(i2c_smbus_xfer); |
1da177e4 LT |
1644 | |
1645 | MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); | |
1646 | MODULE_DESCRIPTION("I2C-Bus main module"); | |
1647 | MODULE_LICENSE("GPL"); |