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 | |
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> | |
b3585e4f | 32 | #include <linux/mutex.h> |
959e85f7 GL |
33 | #include <linux/of_i2c.h> |
34 | #include <linux/of_device.h> | |
b8d6f45b | 35 | #include <linux/completion.h> |
cea443a8 MR |
36 | #include <linux/hardirq.h> |
37 | #include <linux/irqflags.h> | |
f18c41da | 38 | #include <linux/rwsem.h> |
6de468ae | 39 | #include <linux/pm_runtime.h> |
1da177e4 LT |
40 | #include <asm/uaccess.h> |
41 | ||
9c1600ed DB |
42 | #include "i2c-core.h" |
43 | ||
1da177e4 | 44 | |
6629dcff | 45 | /* core_lock protects i2c_adapter_idr, and guarantees |
35fc37f8 JD |
46 | that device detection, deletion of detected devices, and attach_adapter |
47 | and detach_adapter calls are serialized */ | |
caada32a | 48 | static DEFINE_MUTEX(core_lock); |
1da177e4 LT |
49 | static DEFINE_IDR(i2c_adapter_idr); |
50 | ||
4f8cf824 | 51 | static struct device_type i2c_client_type; |
4735c98f | 52 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver); |
f37dd80a DB |
53 | |
54 | /* ------------------------------------------------------------------------- */ | |
55 | ||
d2653e92 JD |
56 | static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, |
57 | const struct i2c_client *client) | |
58 | { | |
59 | while (id->name[0]) { | |
60 | if (strcmp(client->name, id->name) == 0) | |
61 | return id; | |
62 | id++; | |
63 | } | |
64 | return NULL; | |
65 | } | |
66 | ||
1da177e4 LT |
67 | static int i2c_device_match(struct device *dev, struct device_driver *drv) |
68 | { | |
51298d12 JD |
69 | struct i2c_client *client = i2c_verify_client(dev); |
70 | struct i2c_driver *driver; | |
71 | ||
72 | if (!client) | |
73 | return 0; | |
7b4fbc50 | 74 | |
959e85f7 GL |
75 | /* Attempt an OF style match */ |
76 | if (of_driver_match_device(dev, drv)) | |
77 | return 1; | |
78 | ||
51298d12 | 79 | driver = to_i2c_driver(drv); |
d2653e92 JD |
80 | /* match on an id table if there is one */ |
81 | if (driver->id_table) | |
82 | return i2c_match_id(driver->id_table, client) != NULL; | |
83 | ||
eb8a7908 | 84 | return 0; |
1da177e4 LT |
85 | } |
86 | ||
7b4fbc50 DB |
87 | #ifdef CONFIG_HOTPLUG |
88 | ||
89 | /* uevent helps with hotplug: modprobe -q $(MODALIAS) */ | |
7eff2e7a | 90 | static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env) |
7b4fbc50 DB |
91 | { |
92 | struct i2c_client *client = to_i2c_client(dev); | |
7b4fbc50 | 93 | |
eb8a7908 JD |
94 | if (add_uevent_var(env, "MODALIAS=%s%s", |
95 | I2C_MODULE_PREFIX, client->name)) | |
96 | return -ENOMEM; | |
7b4fbc50 DB |
97 | dev_dbg(dev, "uevent\n"); |
98 | return 0; | |
99 | } | |
100 | ||
101 | #else | |
102 | #define i2c_device_uevent NULL | |
103 | #endif /* CONFIG_HOTPLUG */ | |
104 | ||
f37dd80a | 105 | static int i2c_device_probe(struct device *dev) |
1da177e4 | 106 | { |
51298d12 JD |
107 | struct i2c_client *client = i2c_verify_client(dev); |
108 | struct i2c_driver *driver; | |
50c3304a | 109 | int status; |
7b4fbc50 | 110 | |
51298d12 JD |
111 | if (!client) |
112 | return 0; | |
113 | ||
114 | driver = to_i2c_driver(dev->driver); | |
e0457442 | 115 | if (!driver->probe || !driver->id_table) |
7b4fbc50 DB |
116 | return -ENODEV; |
117 | client->driver = driver; | |
ee35425c MP |
118 | if (!device_can_wakeup(&client->dev)) |
119 | device_init_wakeup(&client->dev, | |
120 | client->flags & I2C_CLIENT_WAKE); | |
7b4fbc50 | 121 | dev_dbg(dev, "probe\n"); |
d2653e92 | 122 | |
e0457442 | 123 | status = driver->probe(client, i2c_match_id(driver->id_table, client)); |
e4a7b9b0 | 124 | if (status) { |
50c3304a | 125 | client->driver = NULL; |
e4a7b9b0 WS |
126 | i2c_set_clientdata(client, NULL); |
127 | } | |
50c3304a | 128 | return status; |
f37dd80a | 129 | } |
1da177e4 | 130 | |
f37dd80a DB |
131 | static int i2c_device_remove(struct device *dev) |
132 | { | |
51298d12 | 133 | struct i2c_client *client = i2c_verify_client(dev); |
a1d9e6e4 DB |
134 | struct i2c_driver *driver; |
135 | int status; | |
136 | ||
51298d12 | 137 | if (!client || !dev->driver) |
a1d9e6e4 DB |
138 | return 0; |
139 | ||
140 | driver = to_i2c_driver(dev->driver); | |
141 | if (driver->remove) { | |
142 | dev_dbg(dev, "remove\n"); | |
143 | status = driver->remove(client); | |
144 | } else { | |
145 | dev->driver = NULL; | |
146 | status = 0; | |
147 | } | |
e4a7b9b0 | 148 | if (status == 0) { |
a1d9e6e4 | 149 | client->driver = NULL; |
e4a7b9b0 WS |
150 | i2c_set_clientdata(client, NULL); |
151 | } | |
a1d9e6e4 | 152 | return status; |
1da177e4 LT |
153 | } |
154 | ||
f37dd80a | 155 | static void i2c_device_shutdown(struct device *dev) |
1da177e4 | 156 | { |
51298d12 | 157 | struct i2c_client *client = i2c_verify_client(dev); |
f37dd80a DB |
158 | struct i2c_driver *driver; |
159 | ||
51298d12 | 160 | if (!client || !dev->driver) |
f37dd80a DB |
161 | return; |
162 | driver = to_i2c_driver(dev->driver); | |
163 | if (driver->shutdown) | |
51298d12 | 164 | driver->shutdown(client); |
1da177e4 LT |
165 | } |
166 | ||
2f60ba70 RW |
167 | #ifdef CONFIG_PM_SLEEP |
168 | static int i2c_legacy_suspend(struct device *dev, pm_message_t mesg) | |
54067ee2 | 169 | { |
2f60ba70 RW |
170 | struct i2c_client *client = i2c_verify_client(dev); |
171 | struct i2c_driver *driver; | |
54067ee2 | 172 | |
2f60ba70 | 173 | if (!client || !dev->driver) |
54067ee2 | 174 | return 0; |
2f60ba70 RW |
175 | driver = to_i2c_driver(dev->driver); |
176 | if (!driver->suspend) | |
54067ee2 | 177 | return 0; |
2f60ba70 | 178 | return driver->suspend(client, mesg); |
54067ee2 | 179 | } |
180 | ||
2f60ba70 | 181 | static int i2c_legacy_resume(struct device *dev) |
54067ee2 | 182 | { |
2f60ba70 RW |
183 | struct i2c_client *client = i2c_verify_client(dev); |
184 | struct i2c_driver *driver; | |
54067ee2 | 185 | |
2f60ba70 | 186 | if (!client || !dev->driver) |
54067ee2 | 187 | return 0; |
2f60ba70 RW |
188 | driver = to_i2c_driver(dev->driver); |
189 | if (!driver->resume) | |
54067ee2 | 190 | return 0; |
2f60ba70 | 191 | return driver->resume(client); |
54067ee2 | 192 | } |
54067ee2 | 193 | |
2f60ba70 | 194 | static int i2c_device_pm_suspend(struct device *dev) |
6de468ae | 195 | { |
2f60ba70 | 196 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
6de468ae | 197 | |
2f60ba70 | 198 | if (pm_runtime_suspended(dev)) |
6de468ae | 199 | return 0; |
6de468ae | 200 | |
2f60ba70 RW |
201 | if (pm) |
202 | return pm->suspend ? pm->suspend(dev) : 0; | |
6de468ae | 203 | |
2f60ba70 | 204 | return i2c_legacy_suspend(dev, PMSG_SUSPEND); |
6de468ae MB |
205 | } |
206 | ||
2f60ba70 | 207 | static int i2c_device_pm_resume(struct device *dev) |
6de468ae | 208 | { |
2f60ba70 | 209 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
6de468ae MB |
210 | int ret; |
211 | ||
2f60ba70 RW |
212 | if (pm) |
213 | ret = pm->resume ? pm->resume(dev) : 0; | |
214 | else | |
215 | ret = i2c_legacy_resume(dev); | |
216 | ||
217 | if (!ret) { | |
218 | pm_runtime_disable(dev); | |
219 | pm_runtime_set_active(dev); | |
220 | pm_runtime_enable(dev); | |
6de468ae MB |
221 | } |
222 | ||
2f60ba70 | 223 | return ret; |
6de468ae | 224 | } |
6de468ae | 225 | |
2f60ba70 | 226 | static int i2c_device_pm_freeze(struct device *dev) |
1da177e4 | 227 | { |
2f60ba70 | 228 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
f37dd80a | 229 | |
2f60ba70 | 230 | if (pm_runtime_suspended(dev)) |
f37dd80a | 231 | return 0; |
2f60ba70 RW |
232 | |
233 | if (pm) | |
234 | return pm->freeze ? pm->freeze(dev) : 0; | |
235 | ||
236 | return i2c_legacy_suspend(dev, PMSG_FREEZE); | |
1da177e4 LT |
237 | } |
238 | ||
2f60ba70 | 239 | static int i2c_device_pm_thaw(struct device *dev) |
1da177e4 | 240 | { |
2f60ba70 | 241 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
f37dd80a | 242 | |
2f60ba70 | 243 | if (pm_runtime_suspended(dev)) |
f37dd80a | 244 | return 0; |
2f60ba70 RW |
245 | |
246 | if (pm) | |
247 | return pm->thaw ? pm->thaw(dev) : 0; | |
248 | ||
249 | return i2c_legacy_resume(dev); | |
250 | } | |
251 | ||
252 | static int i2c_device_pm_poweroff(struct device *dev) | |
253 | { | |
254 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; | |
255 | ||
256 | if (pm_runtime_suspended(dev)) | |
f37dd80a | 257 | return 0; |
2f60ba70 RW |
258 | |
259 | if (pm) | |
260 | return pm->poweroff ? pm->poweroff(dev) : 0; | |
261 | ||
262 | return i2c_legacy_suspend(dev, PMSG_HIBERNATE); | |
263 | } | |
264 | ||
265 | static int i2c_device_pm_restore(struct device *dev) | |
266 | { | |
267 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; | |
268 | int ret; | |
269 | ||
270 | if (pm) | |
271 | ret = pm->restore ? pm->restore(dev) : 0; | |
272 | else | |
273 | ret = i2c_legacy_resume(dev); | |
274 | ||
275 | if (!ret) { | |
276 | pm_runtime_disable(dev); | |
277 | pm_runtime_set_active(dev); | |
278 | pm_runtime_enable(dev); | |
279 | } | |
280 | ||
281 | return ret; | |
1da177e4 | 282 | } |
2f60ba70 RW |
283 | #else /* !CONFIG_PM_SLEEP */ |
284 | #define i2c_device_pm_suspend NULL | |
285 | #define i2c_device_pm_resume NULL | |
286 | #define i2c_device_pm_freeze NULL | |
287 | #define i2c_device_pm_thaw NULL | |
288 | #define i2c_device_pm_poweroff NULL | |
289 | #define i2c_device_pm_restore NULL | |
290 | #endif /* !CONFIG_PM_SLEEP */ | |
1da177e4 | 291 | |
9c1600ed DB |
292 | static void i2c_client_dev_release(struct device *dev) |
293 | { | |
294 | kfree(to_i2c_client(dev)); | |
295 | } | |
296 | ||
09b8ce0a | 297 | static ssize_t |
4f8cf824 | 298 | show_name(struct device *dev, struct device_attribute *attr, char *buf) |
7b4fbc50 | 299 | { |
4f8cf824 JD |
300 | return sprintf(buf, "%s\n", dev->type == &i2c_client_type ? |
301 | to_i2c_client(dev)->name : to_i2c_adapter(dev)->name); | |
7b4fbc50 DB |
302 | } |
303 | ||
09b8ce0a ZX |
304 | static ssize_t |
305 | show_modalias(struct device *dev, struct device_attribute *attr, char *buf) | |
7b4fbc50 DB |
306 | { |
307 | struct i2c_client *client = to_i2c_client(dev); | |
eb8a7908 | 308 | return sprintf(buf, "%s%s\n", I2C_MODULE_PREFIX, client->name); |
7b4fbc50 DB |
309 | } |
310 | ||
4f8cf824 | 311 | static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); |
51298d12 JD |
312 | static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL); |
313 | ||
314 | static struct attribute *i2c_dev_attrs[] = { | |
315 | &dev_attr_name.attr, | |
7b4fbc50 | 316 | /* modalias helps coldplug: modprobe $(cat .../modalias) */ |
51298d12 JD |
317 | &dev_attr_modalias.attr, |
318 | NULL | |
319 | }; | |
320 | ||
321 | static struct attribute_group i2c_dev_attr_group = { | |
322 | .attrs = i2c_dev_attrs, | |
323 | }; | |
324 | ||
325 | static const struct attribute_group *i2c_dev_attr_groups[] = { | |
326 | &i2c_dev_attr_group, | |
327 | NULL | |
7b4fbc50 DB |
328 | }; |
329 | ||
0b2c3688 | 330 | static const struct dev_pm_ops i2c_device_pm_ops = { |
54067ee2 | 331 | .suspend = i2c_device_pm_suspend, |
332 | .resume = i2c_device_pm_resume, | |
2f60ba70 RW |
333 | .freeze = i2c_device_pm_freeze, |
334 | .thaw = i2c_device_pm_thaw, | |
335 | .poweroff = i2c_device_pm_poweroff, | |
336 | .restore = i2c_device_pm_restore, | |
337 | SET_RUNTIME_PM_OPS( | |
338 | pm_generic_runtime_suspend, | |
339 | pm_generic_runtime_resume, | |
340 | pm_generic_runtime_idle | |
341 | ) | |
54067ee2 | 342 | }; |
343 | ||
e9ca9eb9 | 344 | struct bus_type i2c_bus_type = { |
f37dd80a DB |
345 | .name = "i2c", |
346 | .match = i2c_device_match, | |
347 | .probe = i2c_device_probe, | |
348 | .remove = i2c_device_remove, | |
349 | .shutdown = i2c_device_shutdown, | |
54067ee2 | 350 | .pm = &i2c_device_pm_ops, |
b864c7d5 | 351 | }; |
e9ca9eb9 | 352 | EXPORT_SYMBOL_GPL(i2c_bus_type); |
b864c7d5 | 353 | |
51298d12 JD |
354 | static struct device_type i2c_client_type = { |
355 | .groups = i2c_dev_attr_groups, | |
356 | .uevent = i2c_device_uevent, | |
357 | .release = i2c_client_dev_release, | |
358 | }; | |
359 | ||
9b766b81 DB |
360 | |
361 | /** | |
362 | * i2c_verify_client - return parameter as i2c_client, or NULL | |
363 | * @dev: device, probably from some driver model iterator | |
364 | * | |
365 | * When traversing the driver model tree, perhaps using driver model | |
366 | * iterators like @device_for_each_child(), you can't assume very much | |
367 | * about the nodes you find. Use this function to avoid oopses caused | |
368 | * by wrongly treating some non-I2C device as an i2c_client. | |
369 | */ | |
370 | struct i2c_client *i2c_verify_client(struct device *dev) | |
371 | { | |
51298d12 | 372 | return (dev->type == &i2c_client_type) |
9b766b81 DB |
373 | ? to_i2c_client(dev) |
374 | : NULL; | |
375 | } | |
376 | EXPORT_SYMBOL(i2c_verify_client); | |
377 | ||
378 | ||
3a89db5f JD |
379 | /* This is a permissive address validity check, I2C address map constraints |
380 | * are purposedly not enforced, except for the general call address. */ | |
381 | static int i2c_check_client_addr_validity(const struct i2c_client *client) | |
382 | { | |
383 | if (client->flags & I2C_CLIENT_TEN) { | |
384 | /* 10-bit address, all values are valid */ | |
385 | if (client->addr > 0x3ff) | |
386 | return -EINVAL; | |
387 | } else { | |
388 | /* 7-bit address, reject the general call address */ | |
389 | if (client->addr == 0x00 || client->addr > 0x7f) | |
390 | return -EINVAL; | |
391 | } | |
392 | return 0; | |
393 | } | |
394 | ||
656b8761 JD |
395 | /* And this is a strict address validity check, used when probing. If a |
396 | * device uses a reserved address, then it shouldn't be probed. 7-bit | |
397 | * addressing is assumed, 10-bit address devices are rare and should be | |
398 | * explicitly enumerated. */ | |
399 | static int i2c_check_addr_validity(unsigned short addr) | |
400 | { | |
401 | /* | |
402 | * Reserved addresses per I2C specification: | |
403 | * 0x00 General call address / START byte | |
404 | * 0x01 CBUS address | |
405 | * 0x02 Reserved for different bus format | |
406 | * 0x03 Reserved for future purposes | |
407 | * 0x04-0x07 Hs-mode master code | |
408 | * 0x78-0x7b 10-bit slave addressing | |
409 | * 0x7c-0x7f Reserved for future purposes | |
410 | */ | |
411 | if (addr < 0x08 || addr > 0x77) | |
412 | return -EINVAL; | |
413 | return 0; | |
414 | } | |
415 | ||
3b5f794b JD |
416 | static int __i2c_check_addr_busy(struct device *dev, void *addrp) |
417 | { | |
418 | struct i2c_client *client = i2c_verify_client(dev); | |
419 | int addr = *(int *)addrp; | |
420 | ||
421 | if (client && client->addr == addr) | |
422 | return -EBUSY; | |
423 | return 0; | |
424 | } | |
425 | ||
426 | static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr) | |
427 | { | |
428 | return device_for_each_child(&adapter->dev, &addr, | |
429 | __i2c_check_addr_busy); | |
430 | } | |
431 | ||
fe61e07e JD |
432 | /** |
433 | * i2c_lock_adapter - Get exclusive access to an I2C bus segment | |
434 | * @adapter: Target I2C bus segment | |
435 | */ | |
436 | void i2c_lock_adapter(struct i2c_adapter *adapter) | |
437 | { | |
438 | rt_mutex_lock(&adapter->bus_lock); | |
439 | } | |
440 | EXPORT_SYMBOL_GPL(i2c_lock_adapter); | |
441 | ||
442 | /** | |
443 | * i2c_trylock_adapter - Try to get exclusive access to an I2C bus segment | |
444 | * @adapter: Target I2C bus segment | |
445 | */ | |
446 | static int i2c_trylock_adapter(struct i2c_adapter *adapter) | |
447 | { | |
448 | return rt_mutex_trylock(&adapter->bus_lock); | |
449 | } | |
450 | ||
451 | /** | |
452 | * i2c_unlock_adapter - Release exclusive access to an I2C bus segment | |
453 | * @adapter: Target I2C bus segment | |
454 | */ | |
455 | void i2c_unlock_adapter(struct i2c_adapter *adapter) | |
456 | { | |
457 | rt_mutex_unlock(&adapter->bus_lock); | |
458 | } | |
459 | EXPORT_SYMBOL_GPL(i2c_unlock_adapter); | |
460 | ||
9c1600ed | 461 | /** |
f8a227e8 | 462 | * i2c_new_device - instantiate an i2c device |
9c1600ed DB |
463 | * @adap: the adapter managing the device |
464 | * @info: describes one I2C device; bus_num is ignored | |
d64f73be | 465 | * Context: can sleep |
9c1600ed | 466 | * |
f8a227e8 JD |
467 | * Create an i2c device. Binding is handled through driver model |
468 | * probe()/remove() methods. A driver may be bound to this device when we | |
469 | * return from this function, or any later moment (e.g. maybe hotplugging will | |
470 | * load the driver module). This call is not appropriate for use by mainboard | |
471 | * initialization logic, which usually runs during an arch_initcall() long | |
472 | * before any i2c_adapter could exist. | |
9c1600ed DB |
473 | * |
474 | * This returns the new i2c client, which may be saved for later use with | |
475 | * i2c_unregister_device(); or NULL to indicate an error. | |
476 | */ | |
477 | struct i2c_client * | |
478 | i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) | |
479 | { | |
480 | struct i2c_client *client; | |
481 | int status; | |
482 | ||
483 | client = kzalloc(sizeof *client, GFP_KERNEL); | |
484 | if (!client) | |
485 | return NULL; | |
486 | ||
487 | client->adapter = adap; | |
488 | ||
489 | client->dev.platform_data = info->platform_data; | |
3bbb835d | 490 | |
11f1f2af AV |
491 | if (info->archdata) |
492 | client->dev.archdata = *info->archdata; | |
493 | ||
ee35425c | 494 | client->flags = info->flags; |
9c1600ed DB |
495 | client->addr = info->addr; |
496 | client->irq = info->irq; | |
497 | ||
9c1600ed DB |
498 | strlcpy(client->name, info->type, sizeof(client->name)); |
499 | ||
3a89db5f JD |
500 | /* Check for address validity */ |
501 | status = i2c_check_client_addr_validity(client); | |
502 | if (status) { | |
503 | dev_err(&adap->dev, "Invalid %d-bit I2C address 0x%02hx\n", | |
504 | client->flags & I2C_CLIENT_TEN ? 10 : 7, client->addr); | |
505 | goto out_err_silent; | |
506 | } | |
507 | ||
f8a227e8 | 508 | /* Check for address business */ |
3b5f794b | 509 | status = i2c_check_addr_busy(adap, client->addr); |
f8a227e8 JD |
510 | if (status) |
511 | goto out_err; | |
512 | ||
513 | client->dev.parent = &client->adapter->dev; | |
514 | client->dev.bus = &i2c_bus_type; | |
51298d12 | 515 | client->dev.type = &i2c_client_type; |
d12d42f7 GL |
516 | #ifdef CONFIG_OF |
517 | client->dev.of_node = info->of_node; | |
518 | #endif | |
f8a227e8 JD |
519 | |
520 | dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap), | |
521 | client->addr); | |
522 | status = device_register(&client->dev); | |
523 | if (status) | |
524 | goto out_err; | |
525 | ||
f8a227e8 JD |
526 | dev_dbg(&adap->dev, "client [%s] registered with bus id %s\n", |
527 | client->name, dev_name(&client->dev)); | |
528 | ||
9c1600ed | 529 | return client; |
f8a227e8 JD |
530 | |
531 | out_err: | |
532 | dev_err(&adap->dev, "Failed to register i2c client %s at 0x%02x " | |
533 | "(%d)\n", client->name, client->addr, status); | |
3a89db5f | 534 | out_err_silent: |
f8a227e8 JD |
535 | kfree(client); |
536 | return NULL; | |
9c1600ed DB |
537 | } |
538 | EXPORT_SYMBOL_GPL(i2c_new_device); | |
539 | ||
540 | ||
541 | /** | |
542 | * i2c_unregister_device - reverse effect of i2c_new_device() | |
543 | * @client: value returned from i2c_new_device() | |
d64f73be | 544 | * Context: can sleep |
9c1600ed DB |
545 | */ |
546 | void i2c_unregister_device(struct i2c_client *client) | |
a1d9e6e4 | 547 | { |
a1d9e6e4 DB |
548 | device_unregister(&client->dev); |
549 | } | |
9c1600ed | 550 | EXPORT_SYMBOL_GPL(i2c_unregister_device); |
a1d9e6e4 DB |
551 | |
552 | ||
60b129d7 JD |
553 | static const struct i2c_device_id dummy_id[] = { |
554 | { "dummy", 0 }, | |
555 | { }, | |
556 | }; | |
557 | ||
d2653e92 JD |
558 | static int dummy_probe(struct i2c_client *client, |
559 | const struct i2c_device_id *id) | |
560 | { | |
561 | return 0; | |
562 | } | |
563 | ||
564 | static int dummy_remove(struct i2c_client *client) | |
e9f1373b DB |
565 | { |
566 | return 0; | |
567 | } | |
568 | ||
569 | static struct i2c_driver dummy_driver = { | |
570 | .driver.name = "dummy", | |
d2653e92 JD |
571 | .probe = dummy_probe, |
572 | .remove = dummy_remove, | |
60b129d7 | 573 | .id_table = dummy_id, |
e9f1373b DB |
574 | }; |
575 | ||
576 | /** | |
577 | * i2c_new_dummy - return a new i2c device bound to a dummy driver | |
578 | * @adapter: the adapter managing the device | |
579 | * @address: seven bit address to be used | |
e9f1373b DB |
580 | * Context: can sleep |
581 | * | |
582 | * This returns an I2C client bound to the "dummy" driver, intended for use | |
583 | * with devices that consume multiple addresses. Examples of such chips | |
584 | * include various EEPROMS (like 24c04 and 24c08 models). | |
585 | * | |
586 | * These dummy devices have two main uses. First, most I2C and SMBus calls | |
587 | * except i2c_transfer() need a client handle; the dummy will be that handle. | |
588 | * And second, this prevents the specified address from being bound to a | |
589 | * different driver. | |
590 | * | |
591 | * This returns the new i2c client, which should be saved for later use with | |
592 | * i2c_unregister_device(); or NULL to indicate an error. | |
593 | */ | |
09b8ce0a | 594 | struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) |
e9f1373b DB |
595 | { |
596 | struct i2c_board_info info = { | |
60b129d7 | 597 | I2C_BOARD_INFO("dummy", address), |
e9f1373b DB |
598 | }; |
599 | ||
e9f1373b DB |
600 | return i2c_new_device(adapter, &info); |
601 | } | |
602 | EXPORT_SYMBOL_GPL(i2c_new_dummy); | |
603 | ||
f37dd80a DB |
604 | /* ------------------------------------------------------------------------- */ |
605 | ||
16ffadfc DB |
606 | /* I2C bus adapters -- one roots each I2C or SMBUS segment */ |
607 | ||
83eaaed0 | 608 | static void i2c_adapter_dev_release(struct device *dev) |
1da177e4 | 609 | { |
ef2c8321 | 610 | struct i2c_adapter *adap = to_i2c_adapter(dev); |
1da177e4 LT |
611 | complete(&adap->dev_released); |
612 | } | |
613 | ||
99cd8e25 JD |
614 | /* |
615 | * Let users instantiate I2C devices through sysfs. This can be used when | |
616 | * platform initialization code doesn't contain the proper data for | |
617 | * whatever reason. Also useful for drivers that do device detection and | |
618 | * detection fails, either because the device uses an unexpected address, | |
619 | * or this is a compatible device with different ID register values. | |
620 | * | |
621 | * Parameter checking may look overzealous, but we really don't want | |
622 | * the user to provide incorrect parameters. | |
623 | */ | |
624 | static ssize_t | |
625 | i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr, | |
626 | const char *buf, size_t count) | |
627 | { | |
628 | struct i2c_adapter *adap = to_i2c_adapter(dev); | |
629 | struct i2c_board_info info; | |
630 | struct i2c_client *client; | |
631 | char *blank, end; | |
632 | int res; | |
633 | ||
634 | dev_warn(dev, "The new_device interface is still experimental " | |
635 | "and may change in a near future\n"); | |
636 | memset(&info, 0, sizeof(struct i2c_board_info)); | |
637 | ||
638 | blank = strchr(buf, ' '); | |
639 | if (!blank) { | |
640 | dev_err(dev, "%s: Missing parameters\n", "new_device"); | |
641 | return -EINVAL; | |
642 | } | |
643 | if (blank - buf > I2C_NAME_SIZE - 1) { | |
644 | dev_err(dev, "%s: Invalid device name\n", "new_device"); | |
645 | return -EINVAL; | |
646 | } | |
647 | memcpy(info.type, buf, blank - buf); | |
648 | ||
649 | /* Parse remaining parameters, reject extra parameters */ | |
650 | res = sscanf(++blank, "%hi%c", &info.addr, &end); | |
651 | if (res < 1) { | |
652 | dev_err(dev, "%s: Can't parse I2C address\n", "new_device"); | |
653 | return -EINVAL; | |
654 | } | |
655 | if (res > 1 && end != '\n') { | |
656 | dev_err(dev, "%s: Extra parameters\n", "new_device"); | |
657 | return -EINVAL; | |
658 | } | |
659 | ||
99cd8e25 JD |
660 | client = i2c_new_device(adap, &info); |
661 | if (!client) | |
3a89db5f | 662 | return -EINVAL; |
99cd8e25 JD |
663 | |
664 | /* Keep track of the added device */ | |
6629dcff JD |
665 | i2c_lock_adapter(adap); |
666 | list_add_tail(&client->detected, &adap->userspace_clients); | |
667 | i2c_unlock_adapter(adap); | |
99cd8e25 JD |
668 | dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device", |
669 | info.type, info.addr); | |
670 | ||
671 | return count; | |
672 | } | |
673 | ||
674 | /* | |
675 | * And of course let the users delete the devices they instantiated, if | |
676 | * they got it wrong. This interface can only be used to delete devices | |
677 | * instantiated by i2c_sysfs_new_device above. This guarantees that we | |
678 | * don't delete devices to which some kernel code still has references. | |
679 | * | |
680 | * Parameter checking may look overzealous, but we really don't want | |
681 | * the user to delete the wrong device. | |
682 | */ | |
683 | static ssize_t | |
684 | i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr, | |
685 | const char *buf, size_t count) | |
686 | { | |
687 | struct i2c_adapter *adap = to_i2c_adapter(dev); | |
688 | struct i2c_client *client, *next; | |
689 | unsigned short addr; | |
690 | char end; | |
691 | int res; | |
692 | ||
693 | /* Parse parameters, reject extra parameters */ | |
694 | res = sscanf(buf, "%hi%c", &addr, &end); | |
695 | if (res < 1) { | |
696 | dev_err(dev, "%s: Can't parse I2C address\n", "delete_device"); | |
697 | return -EINVAL; | |
698 | } | |
699 | if (res > 1 && end != '\n') { | |
700 | dev_err(dev, "%s: Extra parameters\n", "delete_device"); | |
701 | return -EINVAL; | |
702 | } | |
703 | ||
704 | /* Make sure the device was added through sysfs */ | |
705 | res = -ENOENT; | |
6629dcff JD |
706 | i2c_lock_adapter(adap); |
707 | list_for_each_entry_safe(client, next, &adap->userspace_clients, | |
708 | detected) { | |
709 | if (client->addr == addr) { | |
99cd8e25 JD |
710 | dev_info(dev, "%s: Deleting device %s at 0x%02hx\n", |
711 | "delete_device", client->name, client->addr); | |
712 | ||
713 | list_del(&client->detected); | |
714 | i2c_unregister_device(client); | |
715 | res = count; | |
716 | break; | |
717 | } | |
718 | } | |
6629dcff | 719 | i2c_unlock_adapter(adap); |
99cd8e25 JD |
720 | |
721 | if (res < 0) | |
722 | dev_err(dev, "%s: Can't find device in list\n", | |
723 | "delete_device"); | |
724 | return res; | |
725 | } | |
726 | ||
4f8cf824 JD |
727 | static DEVICE_ATTR(new_device, S_IWUSR, NULL, i2c_sysfs_new_device); |
728 | static DEVICE_ATTR(delete_device, S_IWUSR, NULL, i2c_sysfs_delete_device); | |
729 | ||
730 | static struct attribute *i2c_adapter_attrs[] = { | |
731 | &dev_attr_name.attr, | |
732 | &dev_attr_new_device.attr, | |
733 | &dev_attr_delete_device.attr, | |
734 | NULL | |
735 | }; | |
736 | ||
737 | static struct attribute_group i2c_adapter_attr_group = { | |
738 | .attrs = i2c_adapter_attrs, | |
739 | }; | |
740 | ||
741 | static const struct attribute_group *i2c_adapter_attr_groups[] = { | |
742 | &i2c_adapter_attr_group, | |
743 | NULL | |
16ffadfc | 744 | }; |
b119dc3f | 745 | |
4f8cf824 JD |
746 | static struct device_type i2c_adapter_type = { |
747 | .groups = i2c_adapter_attr_groups, | |
748 | .release = i2c_adapter_dev_release, | |
1da177e4 LT |
749 | }; |
750 | ||
2bb5095a JD |
751 | #ifdef CONFIG_I2C_COMPAT |
752 | static struct class_compat *i2c_adapter_compat_class; | |
753 | #endif | |
754 | ||
9c1600ed DB |
755 | static void i2c_scan_static_board_info(struct i2c_adapter *adapter) |
756 | { | |
757 | struct i2c_devinfo *devinfo; | |
758 | ||
f18c41da | 759 | down_read(&__i2c_board_lock); |
9c1600ed DB |
760 | list_for_each_entry(devinfo, &__i2c_board_list, list) { |
761 | if (devinfo->busnum == adapter->nr | |
762 | && !i2c_new_device(adapter, | |
763 | &devinfo->board_info)) | |
09b8ce0a ZX |
764 | dev_err(&adapter->dev, |
765 | "Can't create device at 0x%02x\n", | |
9c1600ed DB |
766 | devinfo->board_info.addr); |
767 | } | |
f18c41da | 768 | up_read(&__i2c_board_lock); |
9c1600ed DB |
769 | } |
770 | ||
69b0089a JD |
771 | static int i2c_do_add_adapter(struct i2c_driver *driver, |
772 | struct i2c_adapter *adap) | |
026526f5 | 773 | { |
4735c98f JD |
774 | /* Detect supported devices on that bus, and instantiate them */ |
775 | i2c_detect(adap, driver); | |
776 | ||
777 | /* Let legacy drivers scan this bus for matching devices */ | |
026526f5 JD |
778 | if (driver->attach_adapter) { |
779 | /* We ignore the return code; if it fails, too bad */ | |
780 | driver->attach_adapter(adap); | |
781 | } | |
782 | return 0; | |
783 | } | |
784 | ||
69b0089a JD |
785 | static int __process_new_adapter(struct device_driver *d, void *data) |
786 | { | |
787 | return i2c_do_add_adapter(to_i2c_driver(d), data); | |
788 | } | |
789 | ||
6e13e641 | 790 | static int i2c_register_adapter(struct i2c_adapter *adap) |
1da177e4 | 791 | { |
026526f5 | 792 | int res = 0, dummy; |
1da177e4 | 793 | |
1d0b19c9 | 794 | /* Can't register until after driver model init */ |
35fc37f8 JD |
795 | if (unlikely(WARN_ON(!i2c_bus_type.p))) { |
796 | res = -EAGAIN; | |
797 | goto out_list; | |
798 | } | |
1d0b19c9 | 799 | |
194684e5 | 800 | rt_mutex_init(&adap->bus_lock); |
6629dcff | 801 | INIT_LIST_HEAD(&adap->userspace_clients); |
1da177e4 | 802 | |
8fcfef6e JD |
803 | /* Set default timeout to 1 second if not already set */ |
804 | if (adap->timeout == 0) | |
805 | adap->timeout = HZ; | |
806 | ||
27d9c183 | 807 | dev_set_name(&adap->dev, "i2c-%d", adap->nr); |
4f8cf824 JD |
808 | adap->dev.bus = &i2c_bus_type; |
809 | adap->dev.type = &i2c_adapter_type; | |
b119c6c9 JD |
810 | res = device_register(&adap->dev); |
811 | if (res) | |
812 | goto out_list; | |
1da177e4 | 813 | |
b6d7b3d1 JD |
814 | dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name); |
815 | ||
2bb5095a JD |
816 | #ifdef CONFIG_I2C_COMPAT |
817 | res = class_compat_create_link(i2c_adapter_compat_class, &adap->dev, | |
818 | adap->dev.parent); | |
819 | if (res) | |
820 | dev_warn(&adap->dev, | |
821 | "Failed to create compatibility class link\n"); | |
822 | #endif | |
823 | ||
729d6dd5 | 824 | /* create pre-declared device nodes */ |
6e13e641 DB |
825 | if (adap->nr < __i2c_first_dynamic_bus_num) |
826 | i2c_scan_static_board_info(adap); | |
827 | ||
959e85f7 GL |
828 | /* Register devices from the device tree */ |
829 | of_i2c_register_devices(adap); | |
830 | ||
4735c98f | 831 | /* Notify drivers */ |
35fc37f8 | 832 | mutex_lock(&core_lock); |
026526f5 | 833 | dummy = bus_for_each_drv(&i2c_bus_type, NULL, adap, |
69b0089a | 834 | __process_new_adapter); |
caada32a | 835 | mutex_unlock(&core_lock); |
35fc37f8 JD |
836 | |
837 | return 0; | |
b119c6c9 | 838 | |
b119c6c9 | 839 | out_list: |
35fc37f8 | 840 | mutex_lock(&core_lock); |
b119c6c9 | 841 | idr_remove(&i2c_adapter_idr, adap->nr); |
35fc37f8 JD |
842 | mutex_unlock(&core_lock); |
843 | return res; | |
1da177e4 LT |
844 | } |
845 | ||
6e13e641 DB |
846 | /** |
847 | * i2c_add_adapter - declare i2c adapter, use dynamic bus number | |
848 | * @adapter: the adapter to add | |
d64f73be | 849 | * Context: can sleep |
6e13e641 DB |
850 | * |
851 | * This routine is used to declare an I2C adapter when its bus number | |
852 | * doesn't matter. Examples: for I2C adapters dynamically added by | |
853 | * USB links or PCI plugin cards. | |
854 | * | |
855 | * When this returns zero, a new bus number was allocated and stored | |
856 | * in adap->nr, and the specified adapter became available for clients. | |
857 | * Otherwise, a negative errno value is returned. | |
858 | */ | |
859 | int i2c_add_adapter(struct i2c_adapter *adapter) | |
860 | { | |
861 | int id, res = 0; | |
862 | ||
863 | retry: | |
864 | if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) | |
865 | return -ENOMEM; | |
866 | ||
caada32a | 867 | mutex_lock(&core_lock); |
6e13e641 DB |
868 | /* "above" here means "above or equal to", sigh */ |
869 | res = idr_get_new_above(&i2c_adapter_idr, adapter, | |
870 | __i2c_first_dynamic_bus_num, &id); | |
caada32a | 871 | mutex_unlock(&core_lock); |
6e13e641 DB |
872 | |
873 | if (res < 0) { | |
874 | if (res == -EAGAIN) | |
875 | goto retry; | |
876 | return res; | |
877 | } | |
878 | ||
879 | adapter->nr = id; | |
880 | return i2c_register_adapter(adapter); | |
881 | } | |
882 | EXPORT_SYMBOL(i2c_add_adapter); | |
883 | ||
884 | /** | |
885 | * i2c_add_numbered_adapter - declare i2c adapter, use static bus number | |
886 | * @adap: the adapter to register (with adap->nr initialized) | |
d64f73be | 887 | * Context: can sleep |
6e13e641 DB |
888 | * |
889 | * This routine is used to declare an I2C adapter when its bus number | |
8c07e46f RD |
890 | * matters. For example, use it for I2C adapters from system-on-chip CPUs, |
891 | * or otherwise built in to the system's mainboard, and where i2c_board_info | |
6e13e641 DB |
892 | * is used to properly configure I2C devices. |
893 | * | |
894 | * If no devices have pre-been declared for this bus, then be sure to | |
895 | * register the adapter before any dynamically allocated ones. Otherwise | |
896 | * the required bus ID may not be available. | |
897 | * | |
898 | * When this returns zero, the specified adapter became available for | |
899 | * clients using the bus number provided in adap->nr. Also, the table | |
900 | * of I2C devices pre-declared using i2c_register_board_info() is scanned, | |
901 | * and the appropriate driver model device nodes are created. Otherwise, a | |
902 | * negative errno value is returned. | |
903 | */ | |
904 | int i2c_add_numbered_adapter(struct i2c_adapter *adap) | |
905 | { | |
906 | int id; | |
907 | int status; | |
908 | ||
909 | if (adap->nr & ~MAX_ID_MASK) | |
910 | return -EINVAL; | |
911 | ||
912 | retry: | |
913 | if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) | |
914 | return -ENOMEM; | |
915 | ||
caada32a | 916 | mutex_lock(&core_lock); |
6e13e641 DB |
917 | /* "above" here means "above or equal to", sigh; |
918 | * we need the "equal to" result to force the result | |
919 | */ | |
920 | status = idr_get_new_above(&i2c_adapter_idr, adap, adap->nr, &id); | |
921 | if (status == 0 && id != adap->nr) { | |
922 | status = -EBUSY; | |
923 | idr_remove(&i2c_adapter_idr, id); | |
924 | } | |
caada32a | 925 | mutex_unlock(&core_lock); |
6e13e641 DB |
926 | if (status == -EAGAIN) |
927 | goto retry; | |
928 | ||
929 | if (status == 0) | |
930 | status = i2c_register_adapter(adap); | |
931 | return status; | |
932 | } | |
933 | EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter); | |
934 | ||
69b0089a JD |
935 | static int i2c_do_del_adapter(struct i2c_driver *driver, |
936 | struct i2c_adapter *adapter) | |
026526f5 | 937 | { |
4735c98f | 938 | struct i2c_client *client, *_n; |
026526f5 JD |
939 | int res; |
940 | ||
acec211c JD |
941 | /* Remove the devices we created ourselves as the result of hardware |
942 | * probing (using a driver's detect method) */ | |
4735c98f JD |
943 | list_for_each_entry_safe(client, _n, &driver->clients, detected) { |
944 | if (client->adapter == adapter) { | |
945 | dev_dbg(&adapter->dev, "Removing %s at 0x%x\n", | |
946 | client->name, client->addr); | |
947 | list_del(&client->detected); | |
948 | i2c_unregister_device(client); | |
949 | } | |
950 | } | |
951 | ||
026526f5 JD |
952 | if (!driver->detach_adapter) |
953 | return 0; | |
954 | res = driver->detach_adapter(adapter); | |
955 | if (res) | |
956 | dev_err(&adapter->dev, "detach_adapter failed (%d) " | |
957 | "for driver [%s]\n", res, driver->driver.name); | |
958 | return res; | |
959 | } | |
960 | ||
e549c2b5 JD |
961 | static int __unregister_client(struct device *dev, void *dummy) |
962 | { | |
963 | struct i2c_client *client = i2c_verify_client(dev); | |
964 | if (client) | |
965 | i2c_unregister_device(client); | |
966 | return 0; | |
967 | } | |
968 | ||
69b0089a JD |
969 | static int __process_removed_adapter(struct device_driver *d, void *data) |
970 | { | |
971 | return i2c_do_del_adapter(to_i2c_driver(d), data); | |
972 | } | |
973 | ||
d64f73be DB |
974 | /** |
975 | * i2c_del_adapter - unregister I2C adapter | |
976 | * @adap: the adapter being unregistered | |
977 | * Context: can sleep | |
978 | * | |
979 | * This unregisters an I2C adapter which was previously registered | |
980 | * by @i2c_add_adapter or @i2c_add_numbered_adapter. | |
981 | */ | |
1da177e4 LT |
982 | int i2c_del_adapter(struct i2c_adapter *adap) |
983 | { | |
1da177e4 | 984 | int res = 0; |
35fc37f8 | 985 | struct i2c_adapter *found; |
bbd2d9c9 | 986 | struct i2c_client *client, *next; |
1da177e4 LT |
987 | |
988 | /* First make sure that this adapter was ever added */ | |
35fc37f8 JD |
989 | mutex_lock(&core_lock); |
990 | found = idr_find(&i2c_adapter_idr, adap->nr); | |
991 | mutex_unlock(&core_lock); | |
992 | if (found != adap) { | |
b6d7b3d1 JD |
993 | pr_debug("i2c-core: attempting to delete unregistered " |
994 | "adapter [%s]\n", adap->name); | |
35fc37f8 | 995 | return -EINVAL; |
1da177e4 LT |
996 | } |
997 | ||
026526f5 | 998 | /* Tell drivers about this removal */ |
35fc37f8 | 999 | mutex_lock(&core_lock); |
026526f5 | 1000 | res = bus_for_each_drv(&i2c_bus_type, NULL, adap, |
69b0089a | 1001 | __process_removed_adapter); |
35fc37f8 | 1002 | mutex_unlock(&core_lock); |
026526f5 | 1003 | if (res) |
35fc37f8 | 1004 | return res; |
1da177e4 | 1005 | |
bbd2d9c9 | 1006 | /* Remove devices instantiated from sysfs */ |
6629dcff JD |
1007 | i2c_lock_adapter(adap); |
1008 | list_for_each_entry_safe(client, next, &adap->userspace_clients, | |
1009 | detected) { | |
1010 | dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name, | |
1011 | client->addr); | |
1012 | list_del(&client->detected); | |
1013 | i2c_unregister_device(client); | |
bbd2d9c9 | 1014 | } |
6629dcff | 1015 | i2c_unlock_adapter(adap); |
bbd2d9c9 | 1016 | |
e549c2b5 JD |
1017 | /* Detach any active clients. This can't fail, thus we do not |
1018 | checking the returned value. */ | |
1019 | res = device_for_each_child(&adap->dev, NULL, __unregister_client); | |
1da177e4 | 1020 | |
2bb5095a JD |
1021 | #ifdef CONFIG_I2C_COMPAT |
1022 | class_compat_remove_link(i2c_adapter_compat_class, &adap->dev, | |
1023 | adap->dev.parent); | |
1024 | #endif | |
1025 | ||
c5567521 TLSC |
1026 | /* device name is gone after device_unregister */ |
1027 | dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name); | |
1028 | ||
1da177e4 LT |
1029 | /* clean up the sysfs representation */ |
1030 | init_completion(&adap->dev_released); | |
1da177e4 | 1031 | device_unregister(&adap->dev); |
1da177e4 LT |
1032 | |
1033 | /* wait for sysfs to drop all references */ | |
1034 | wait_for_completion(&adap->dev_released); | |
1da177e4 | 1035 | |
6e13e641 | 1036 | /* free bus id */ |
35fc37f8 | 1037 | mutex_lock(&core_lock); |
1da177e4 | 1038 | idr_remove(&i2c_adapter_idr, adap->nr); |
35fc37f8 | 1039 | mutex_unlock(&core_lock); |
1da177e4 | 1040 | |
bd4bc3db JD |
1041 | /* Clear the device structure in case this adapter is ever going to be |
1042 | added again */ | |
1043 | memset(&adap->dev, 0, sizeof(adap->dev)); | |
1044 | ||
35fc37f8 | 1045 | return 0; |
1da177e4 | 1046 | } |
c0564606 | 1047 | EXPORT_SYMBOL(i2c_del_adapter); |
1da177e4 LT |
1048 | |
1049 | ||
7b4fbc50 DB |
1050 | /* ------------------------------------------------------------------------- */ |
1051 | ||
69b0089a | 1052 | static int __process_new_driver(struct device *dev, void *data) |
7f101a97 | 1053 | { |
4f8cf824 JD |
1054 | if (dev->type != &i2c_adapter_type) |
1055 | return 0; | |
69b0089a | 1056 | return i2c_do_add_adapter(data, to_i2c_adapter(dev)); |
7f101a97 DY |
1057 | } |
1058 | ||
7b4fbc50 DB |
1059 | /* |
1060 | * An i2c_driver is used with one or more i2c_client (device) nodes to access | |
729d6dd5 | 1061 | * i2c slave chips, on a bus instance associated with some i2c_adapter. |
1da177e4 LT |
1062 | */ |
1063 | ||
de59cf9e | 1064 | int i2c_register_driver(struct module *owner, struct i2c_driver *driver) |
1da177e4 | 1065 | { |
7eebcb7c | 1066 | int res; |
1da177e4 | 1067 | |
1d0b19c9 DB |
1068 | /* Can't register until after driver model init */ |
1069 | if (unlikely(WARN_ON(!i2c_bus_type.p))) | |
1070 | return -EAGAIN; | |
1071 | ||
1da177e4 | 1072 | /* add the driver to the list of i2c drivers in the driver core */ |
de59cf9e | 1073 | driver->driver.owner = owner; |
1da177e4 | 1074 | driver->driver.bus = &i2c_bus_type; |
1da177e4 | 1075 | |
729d6dd5 | 1076 | /* When registration returns, the driver core |
6e13e641 DB |
1077 | * will have called probe() for all matching-but-unbound devices. |
1078 | */ | |
1da177e4 LT |
1079 | res = driver_register(&driver->driver); |
1080 | if (res) | |
7eebcb7c | 1081 | return res; |
438d6c2c | 1082 | |
35d8b2e6 | 1083 | pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name); |
1da177e4 | 1084 | |
4735c98f JD |
1085 | INIT_LIST_HEAD(&driver->clients); |
1086 | /* Walk the adapters that are already present */ | |
35fc37f8 | 1087 | mutex_lock(&core_lock); |
69b0089a | 1088 | bus_for_each_dev(&i2c_bus_type, NULL, driver, __process_new_driver); |
7f101a97 | 1089 | mutex_unlock(&core_lock); |
35fc37f8 | 1090 | |
7f101a97 DY |
1091 | return 0; |
1092 | } | |
1093 | EXPORT_SYMBOL(i2c_register_driver); | |
1094 | ||
69b0089a | 1095 | static int __process_removed_driver(struct device *dev, void *data) |
7f101a97 | 1096 | { |
4f8cf824 JD |
1097 | if (dev->type != &i2c_adapter_type) |
1098 | return 0; | |
69b0089a | 1099 | return i2c_do_del_adapter(data, to_i2c_adapter(dev)); |
1da177e4 LT |
1100 | } |
1101 | ||
a1d9e6e4 DB |
1102 | /** |
1103 | * i2c_del_driver - unregister I2C driver | |
1104 | * @driver: the driver being unregistered | |
d64f73be | 1105 | * Context: can sleep |
a1d9e6e4 | 1106 | */ |
b3e82096 | 1107 | void i2c_del_driver(struct i2c_driver *driver) |
1da177e4 | 1108 | { |
caada32a | 1109 | mutex_lock(&core_lock); |
69b0089a | 1110 | bus_for_each_dev(&i2c_bus_type, NULL, driver, __process_removed_driver); |
35fc37f8 | 1111 | mutex_unlock(&core_lock); |
1da177e4 LT |
1112 | |
1113 | driver_unregister(&driver->driver); | |
35d8b2e6 | 1114 | pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name); |
1da177e4 | 1115 | } |
c0564606 | 1116 | EXPORT_SYMBOL(i2c_del_driver); |
1da177e4 | 1117 | |
7b4fbc50 DB |
1118 | /* ------------------------------------------------------------------------- */ |
1119 | ||
e48d3319 JD |
1120 | /** |
1121 | * i2c_use_client - increments the reference count of the i2c client structure | |
1122 | * @client: the client being referenced | |
1123 | * | |
1124 | * Each live reference to a client should be refcounted. The driver model does | |
1125 | * that automatically as part of driver binding, so that most drivers don't | |
1126 | * need to do this explicitly: they hold a reference until they're unbound | |
1127 | * from the device. | |
1128 | * | |
1129 | * A pointer to the client with the incremented reference counter is returned. | |
1130 | */ | |
1131 | struct i2c_client *i2c_use_client(struct i2c_client *client) | |
1da177e4 | 1132 | { |
6ea438ec DB |
1133 | if (client && get_device(&client->dev)) |
1134 | return client; | |
1135 | return NULL; | |
1da177e4 | 1136 | } |
c0564606 | 1137 | EXPORT_SYMBOL(i2c_use_client); |
1da177e4 | 1138 | |
e48d3319 JD |
1139 | /** |
1140 | * i2c_release_client - release a use of the i2c client structure | |
1141 | * @client: the client being no longer referenced | |
1142 | * | |
1143 | * Must be called when a user of a client is finished with it. | |
1144 | */ | |
1145 | void i2c_release_client(struct i2c_client *client) | |
1da177e4 | 1146 | { |
6ea438ec DB |
1147 | if (client) |
1148 | put_device(&client->dev); | |
1da177e4 | 1149 | } |
c0564606 | 1150 | EXPORT_SYMBOL(i2c_release_client); |
1da177e4 | 1151 | |
9b766b81 DB |
1152 | struct i2c_cmd_arg { |
1153 | unsigned cmd; | |
1154 | void *arg; | |
1155 | }; | |
1156 | ||
1157 | static int i2c_cmd(struct device *dev, void *_arg) | |
1158 | { | |
1159 | struct i2c_client *client = i2c_verify_client(dev); | |
1160 | struct i2c_cmd_arg *arg = _arg; | |
1161 | ||
1162 | if (client && client->driver && client->driver->command) | |
1163 | client->driver->command(client, arg->cmd, arg->arg); | |
1164 | return 0; | |
1165 | } | |
1166 | ||
1da177e4 LT |
1167 | void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg) |
1168 | { | |
9b766b81 | 1169 | struct i2c_cmd_arg cmd_arg; |
1da177e4 | 1170 | |
9b766b81 DB |
1171 | cmd_arg.cmd = cmd; |
1172 | cmd_arg.arg = arg; | |
1173 | device_for_each_child(&adap->dev, &cmd_arg, i2c_cmd); | |
1da177e4 | 1174 | } |
c0564606 | 1175 | EXPORT_SYMBOL(i2c_clients_command); |
1da177e4 LT |
1176 | |
1177 | static int __init i2c_init(void) | |
1178 | { | |
1179 | int retval; | |
1180 | ||
1181 | retval = bus_register(&i2c_bus_type); | |
1da177e4 LT |
1182 | if (retval) |
1183 | return retval; | |
2bb5095a JD |
1184 | #ifdef CONFIG_I2C_COMPAT |
1185 | i2c_adapter_compat_class = class_compat_register("i2c-adapter"); | |
1186 | if (!i2c_adapter_compat_class) { | |
1187 | retval = -ENOMEM; | |
1188 | goto bus_err; | |
1189 | } | |
1190 | #endif | |
e9f1373b DB |
1191 | retval = i2c_add_driver(&dummy_driver); |
1192 | if (retval) | |
2bb5095a | 1193 | goto class_err; |
e9f1373b DB |
1194 | return 0; |
1195 | ||
2bb5095a JD |
1196 | class_err: |
1197 | #ifdef CONFIG_I2C_COMPAT | |
1198 | class_compat_unregister(i2c_adapter_compat_class); | |
e9f1373b | 1199 | bus_err: |
2bb5095a | 1200 | #endif |
e9f1373b DB |
1201 | bus_unregister(&i2c_bus_type); |
1202 | return retval; | |
1da177e4 LT |
1203 | } |
1204 | ||
1205 | static void __exit i2c_exit(void) | |
1206 | { | |
e9f1373b | 1207 | i2c_del_driver(&dummy_driver); |
2bb5095a JD |
1208 | #ifdef CONFIG_I2C_COMPAT |
1209 | class_compat_unregister(i2c_adapter_compat_class); | |
1210 | #endif | |
1da177e4 LT |
1211 | bus_unregister(&i2c_bus_type); |
1212 | } | |
1213 | ||
a10f9e7c DB |
1214 | /* We must initialize early, because some subsystems register i2c drivers |
1215 | * in subsys_initcall() code, but are linked (and initialized) before i2c. | |
1216 | */ | |
1217 | postcore_initcall(i2c_init); | |
1da177e4 LT |
1218 | module_exit(i2c_exit); |
1219 | ||
1220 | /* ---------------------------------------------------- | |
1221 | * the functional interface to the i2c busses. | |
1222 | * ---------------------------------------------------- | |
1223 | */ | |
1224 | ||
a1cdedac DB |
1225 | /** |
1226 | * i2c_transfer - execute a single or combined I2C message | |
1227 | * @adap: Handle to I2C bus | |
1228 | * @msgs: One or more messages to execute before STOP is issued to | |
1229 | * terminate the operation; each message begins with a START. | |
1230 | * @num: Number of messages to be executed. | |
1231 | * | |
1232 | * Returns negative errno, else the number of messages executed. | |
1233 | * | |
1234 | * Note that there is no requirement that each message be sent to | |
1235 | * the same slave address, although that is the most common model. | |
1236 | */ | |
09b8ce0a | 1237 | int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) |
1da177e4 | 1238 | { |
66b650f0 CW |
1239 | unsigned long orig_jiffies; |
1240 | int ret, try; | |
1da177e4 | 1241 | |
a1cdedac DB |
1242 | /* REVISIT the fault reporting model here is weak: |
1243 | * | |
1244 | * - When we get an error after receiving N bytes from a slave, | |
1245 | * there is no way to report "N". | |
1246 | * | |
1247 | * - When we get a NAK after transmitting N bytes to a slave, | |
1248 | * there is no way to report "N" ... or to let the master | |
1249 | * continue executing the rest of this combined message, if | |
1250 | * that's the appropriate response. | |
1251 | * | |
1252 | * - When for example "num" is two and we successfully complete | |
1253 | * the first message but get an error part way through the | |
1254 | * second, it's unclear whether that should be reported as | |
1255 | * one (discarding status on the second message) or errno | |
1256 | * (discarding status on the first one). | |
1257 | */ | |
1258 | ||
1da177e4 LT |
1259 | if (adap->algo->master_xfer) { |
1260 | #ifdef DEBUG | |
1261 | for (ret = 0; ret < num; ret++) { | |
1262 | dev_dbg(&adap->dev, "master_xfer[%d] %c, addr=0x%02x, " | |
209d27c3 JD |
1263 | "len=%d%s\n", ret, (msgs[ret].flags & I2C_M_RD) |
1264 | ? 'R' : 'W', msgs[ret].addr, msgs[ret].len, | |
1265 | (msgs[ret].flags & I2C_M_RECV_LEN) ? "+" : ""); | |
1da177e4 LT |
1266 | } |
1267 | #endif | |
1268 | ||
cea443a8 | 1269 | if (in_atomic() || irqs_disabled()) { |
fe61e07e | 1270 | ret = i2c_trylock_adapter(adap); |
cea443a8 MR |
1271 | if (!ret) |
1272 | /* I2C activity is ongoing. */ | |
1273 | return -EAGAIN; | |
1274 | } else { | |
fe61e07e | 1275 | i2c_lock_adapter(adap); |
cea443a8 MR |
1276 | } |
1277 | ||
66b650f0 CW |
1278 | /* Retry automatically on arbitration loss */ |
1279 | orig_jiffies = jiffies; | |
1280 | for (ret = 0, try = 0; try <= adap->retries; try++) { | |
1281 | ret = adap->algo->master_xfer(adap, msgs, num); | |
1282 | if (ret != -EAGAIN) | |
1283 | break; | |
1284 | if (time_after(jiffies, orig_jiffies + adap->timeout)) | |
1285 | break; | |
1286 | } | |
fe61e07e | 1287 | i2c_unlock_adapter(adap); |
1da177e4 LT |
1288 | |
1289 | return ret; | |
1290 | } else { | |
1291 | dev_dbg(&adap->dev, "I2C level transfers not supported\n"); | |
24a5bb7b | 1292 | return -EOPNOTSUPP; |
1da177e4 LT |
1293 | } |
1294 | } | |
c0564606 | 1295 | EXPORT_SYMBOL(i2c_transfer); |
1da177e4 | 1296 | |
a1cdedac DB |
1297 | /** |
1298 | * i2c_master_send - issue a single I2C message in master transmit mode | |
1299 | * @client: Handle to slave device | |
1300 | * @buf: Data that will be written to the slave | |
0c43ea54 | 1301 | * @count: How many bytes to write, must be less than 64k since msg.len is u16 |
a1cdedac DB |
1302 | * |
1303 | * Returns negative errno, or else the number of bytes written. | |
1304 | */ | |
7225acf4 | 1305 | int i2c_master_send(struct i2c_client *client, const char *buf, int count) |
1da177e4 LT |
1306 | { |
1307 | int ret; | |
7225acf4 | 1308 | struct i2c_adapter *adap = client->adapter; |
1da177e4 LT |
1309 | struct i2c_msg msg; |
1310 | ||
815f55f2 JD |
1311 | msg.addr = client->addr; |
1312 | msg.flags = client->flags & I2C_M_TEN; | |
1313 | msg.len = count; | |
1314 | msg.buf = (char *)buf; | |
438d6c2c | 1315 | |
815f55f2 | 1316 | ret = i2c_transfer(adap, &msg, 1); |
1da177e4 | 1317 | |
815f55f2 JD |
1318 | /* If everything went ok (i.e. 1 msg transmitted), return #bytes |
1319 | transmitted, else error code. */ | |
1320 | return (ret == 1) ? count : ret; | |
1da177e4 | 1321 | } |
c0564606 | 1322 | EXPORT_SYMBOL(i2c_master_send); |
1da177e4 | 1323 | |
a1cdedac DB |
1324 | /** |
1325 | * i2c_master_recv - issue a single I2C message in master receive mode | |
1326 | * @client: Handle to slave device | |
1327 | * @buf: Where to store data read from slave | |
0c43ea54 | 1328 | * @count: How many bytes to read, must be less than 64k since msg.len is u16 |
a1cdedac DB |
1329 | * |
1330 | * Returns negative errno, or else the number of bytes read. | |
1331 | */ | |
7225acf4 | 1332 | int i2c_master_recv(struct i2c_client *client, char *buf, int count) |
1da177e4 | 1333 | { |
7225acf4 | 1334 | struct i2c_adapter *adap = client->adapter; |
1da177e4 LT |
1335 | struct i2c_msg msg; |
1336 | int ret; | |
815f55f2 JD |
1337 | |
1338 | msg.addr = client->addr; | |
1339 | msg.flags = client->flags & I2C_M_TEN; | |
1340 | msg.flags |= I2C_M_RD; | |
1341 | msg.len = count; | |
1342 | msg.buf = buf; | |
1343 | ||
1344 | ret = i2c_transfer(adap, &msg, 1); | |
1345 | ||
1346 | /* If everything went ok (i.e. 1 msg transmitted), return #bytes | |
1347 | transmitted, else error code. */ | |
1348 | return (ret == 1) ? count : ret; | |
1da177e4 | 1349 | } |
c0564606 | 1350 | EXPORT_SYMBOL(i2c_master_recv); |
1da177e4 | 1351 | |
1da177e4 LT |
1352 | /* ---------------------------------------------------- |
1353 | * the i2c address scanning function | |
1354 | * Will not work for 10-bit addresses! | |
1355 | * ---------------------------------------------------- | |
1356 | */ | |
1da177e4 | 1357 | |
63e4e802 JD |
1358 | /* |
1359 | * Legacy default probe function, mostly relevant for SMBus. The default | |
1360 | * probe method is a quick write, but it is known to corrupt the 24RF08 | |
1361 | * EEPROMs due to a state machine bug, and could also irreversibly | |
1362 | * write-protect some EEPROMs, so for address ranges 0x30-0x37 and 0x50-0x5f, | |
1363 | * we use a short byte read instead. Also, some bus drivers don't implement | |
1364 | * quick write, so we fallback to a byte read in that case too. | |
1365 | * On x86, there is another special case for FSC hardware monitoring chips, | |
1366 | * which want regular byte reads (address 0x73.) Fortunately, these are the | |
1367 | * only known chips using this I2C address on PC hardware. | |
1368 | * Returns 1 if probe succeeded, 0 if not. | |
1369 | */ | |
1370 | static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr) | |
1371 | { | |
1372 | int err; | |
1373 | union i2c_smbus_data dummy; | |
1374 | ||
1375 | #ifdef CONFIG_X86 | |
1376 | if (addr == 0x73 && (adap->class & I2C_CLASS_HWMON) | |
1377 | && i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE_DATA)) | |
1378 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
1379 | I2C_SMBUS_BYTE_DATA, &dummy); | |
1380 | else | |
1381 | #endif | |
1382 | if ((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50 | |
1383 | || !i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) | |
1384 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
1385 | I2C_SMBUS_BYTE, &dummy); | |
1386 | else | |
1387 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0, | |
1388 | I2C_SMBUS_QUICK, NULL); | |
1389 | ||
1390 | return err >= 0; | |
1391 | } | |
1392 | ||
ccfbbd08 | 1393 | static int i2c_detect_address(struct i2c_client *temp_client, |
4735c98f JD |
1394 | struct i2c_driver *driver) |
1395 | { | |
1396 | struct i2c_board_info info; | |
1397 | struct i2c_adapter *adapter = temp_client->adapter; | |
1398 | int addr = temp_client->addr; | |
1399 | int err; | |
1400 | ||
1401 | /* Make sure the address is valid */ | |
656b8761 JD |
1402 | err = i2c_check_addr_validity(addr); |
1403 | if (err) { | |
4735c98f JD |
1404 | dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n", |
1405 | addr); | |
656b8761 | 1406 | return err; |
4735c98f JD |
1407 | } |
1408 | ||
1409 | /* Skip if already in use */ | |
3b5f794b | 1410 | if (i2c_check_addr_busy(adapter, addr)) |
4735c98f JD |
1411 | return 0; |
1412 | ||
ccfbbd08 | 1413 | /* Make sure there is something at this address */ |
63e4e802 JD |
1414 | if (!i2c_default_probe(adapter, addr)) |
1415 | return 0; | |
4735c98f JD |
1416 | |
1417 | /* Finally call the custom detection function */ | |
1418 | memset(&info, 0, sizeof(struct i2c_board_info)); | |
1419 | info.addr = addr; | |
310ec792 | 1420 | err = driver->detect(temp_client, &info); |
4735c98f JD |
1421 | if (err) { |
1422 | /* -ENODEV is returned if the detection fails. We catch it | |
1423 | here as this isn't an error. */ | |
1424 | return err == -ENODEV ? 0 : err; | |
1425 | } | |
1426 | ||
1427 | /* Consistency check */ | |
1428 | if (info.type[0] == '\0') { | |
1429 | dev_err(&adapter->dev, "%s detection function provided " | |
1430 | "no name for 0x%x\n", driver->driver.name, | |
1431 | addr); | |
1432 | } else { | |
1433 | struct i2c_client *client; | |
1434 | ||
1435 | /* Detection succeeded, instantiate the device */ | |
1436 | dev_dbg(&adapter->dev, "Creating %s at 0x%02x\n", | |
1437 | info.type, info.addr); | |
1438 | client = i2c_new_device(adapter, &info); | |
1439 | if (client) | |
1440 | list_add_tail(&client->detected, &driver->clients); | |
1441 | else | |
1442 | dev_err(&adapter->dev, "Failed creating %s at 0x%02x\n", | |
1443 | info.type, info.addr); | |
1444 | } | |
1445 | return 0; | |
1446 | } | |
1447 | ||
1448 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver) | |
1449 | { | |
c3813d6a | 1450 | const unsigned short *address_list; |
4735c98f JD |
1451 | struct i2c_client *temp_client; |
1452 | int i, err = 0; | |
1453 | int adap_id = i2c_adapter_id(adapter); | |
1454 | ||
c3813d6a JD |
1455 | address_list = driver->address_list; |
1456 | if (!driver->detect || !address_list) | |
4735c98f JD |
1457 | return 0; |
1458 | ||
1459 | /* Set up a temporary client to help detect callback */ | |
1460 | temp_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL); | |
1461 | if (!temp_client) | |
1462 | return -ENOMEM; | |
1463 | temp_client->adapter = adapter; | |
1464 | ||
4329cf86 JD |
1465 | /* Stop here if the classes do not match */ |
1466 | if (!(adapter->class & driver->class)) | |
1467 | goto exit_free; | |
1468 | ||
827900c5 JD |
1469 | /* Stop here if the bus doesn't support probing */ |
1470 | if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE)) { | |
c3813d6a | 1471 | if (address_list[0] == I2C_CLIENT_END) |
4735c98f JD |
1472 | goto exit_free; |
1473 | ||
827900c5 | 1474 | dev_warn(&adapter->dev, "Probing not supported\n"); |
4735c98f JD |
1475 | err = -EOPNOTSUPP; |
1476 | goto exit_free; | |
1477 | } | |
1478 | ||
c3813d6a | 1479 | for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) { |
4735c98f | 1480 | dev_dbg(&adapter->dev, "found normal entry for adapter %d, " |
c3813d6a JD |
1481 | "addr 0x%02x\n", adap_id, address_list[i]); |
1482 | temp_client->addr = address_list[i]; | |
ccfbbd08 | 1483 | err = i2c_detect_address(temp_client, driver); |
4735c98f JD |
1484 | if (err) |
1485 | goto exit_free; | |
1486 | } | |
1487 | ||
1488 | exit_free: | |
1489 | kfree(temp_client); | |
1490 | return err; | |
1491 | } | |
1492 | ||
d44f19d5 JD |
1493 | int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr) |
1494 | { | |
1495 | return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
1496 | I2C_SMBUS_QUICK, NULL) >= 0; | |
1497 | } | |
1498 | EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read); | |
1499 | ||
12b5053a JD |
1500 | struct i2c_client * |
1501 | i2c_new_probed_device(struct i2c_adapter *adap, | |
1502 | struct i2c_board_info *info, | |
9a94241a JD |
1503 | unsigned short const *addr_list, |
1504 | int (*probe)(struct i2c_adapter *, unsigned short addr)) | |
12b5053a JD |
1505 | { |
1506 | int i; | |
1507 | ||
9a94241a JD |
1508 | if (!probe) { |
1509 | /* Stop here if the bus doesn't support probing */ | |
1510 | if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) { | |
1511 | dev_err(&adap->dev, "Probing not supported\n"); | |
1512 | return NULL; | |
1513 | } | |
1514 | probe = i2c_default_probe; | |
12b5053a JD |
1515 | } |
1516 | ||
12b5053a JD |
1517 | for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { |
1518 | /* Check address validity */ | |
656b8761 | 1519 | if (i2c_check_addr_validity(addr_list[i]) < 0) { |
12b5053a JD |
1520 | dev_warn(&adap->dev, "Invalid 7-bit address " |
1521 | "0x%02x\n", addr_list[i]); | |
1522 | continue; | |
1523 | } | |
1524 | ||
1525 | /* Check address availability */ | |
3b5f794b | 1526 | if (i2c_check_addr_busy(adap, addr_list[i])) { |
12b5053a JD |
1527 | dev_dbg(&adap->dev, "Address 0x%02x already in " |
1528 | "use, not probing\n", addr_list[i]); | |
1529 | continue; | |
1530 | } | |
1531 | ||
63e4e802 | 1532 | /* Test address responsiveness */ |
9a94241a | 1533 | if (probe(adap, addr_list[i])) |
63e4e802 | 1534 | break; |
12b5053a | 1535 | } |
12b5053a JD |
1536 | |
1537 | if (addr_list[i] == I2C_CLIENT_END) { | |
1538 | dev_dbg(&adap->dev, "Probing failed, no device found\n"); | |
1539 | return NULL; | |
1540 | } | |
1541 | ||
1542 | info->addr = addr_list[i]; | |
1543 | return i2c_new_device(adap, info); | |
1544 | } | |
1545 | EXPORT_SYMBOL_GPL(i2c_new_probed_device); | |
1546 | ||
7225acf4 | 1547 | struct i2c_adapter *i2c_get_adapter(int id) |
1da177e4 | 1548 | { |
1da177e4 | 1549 | struct i2c_adapter *adapter; |
438d6c2c | 1550 | |
caada32a | 1551 | mutex_lock(&core_lock); |
1cf92b45 | 1552 | adapter = idr_find(&i2c_adapter_idr, id); |
a0920e10 MH |
1553 | if (adapter && !try_module_get(adapter->owner)) |
1554 | adapter = NULL; | |
1555 | ||
caada32a | 1556 | mutex_unlock(&core_lock); |
a0920e10 | 1557 | return adapter; |
1da177e4 | 1558 | } |
c0564606 | 1559 | EXPORT_SYMBOL(i2c_get_adapter); |
1da177e4 LT |
1560 | |
1561 | void i2c_put_adapter(struct i2c_adapter *adap) | |
1562 | { | |
1563 | module_put(adap->owner); | |
1564 | } | |
c0564606 | 1565 | EXPORT_SYMBOL(i2c_put_adapter); |
1da177e4 LT |
1566 | |
1567 | /* The SMBus parts */ | |
1568 | ||
438d6c2c | 1569 | #define POLY (0x1070U << 3) |
09b8ce0a | 1570 | static u8 crc8(u16 data) |
1da177e4 LT |
1571 | { |
1572 | int i; | |
438d6c2c | 1573 | |
7225acf4 | 1574 | for (i = 0; i < 8; i++) { |
438d6c2c | 1575 | if (data & 0x8000) |
1da177e4 LT |
1576 | data = data ^ POLY; |
1577 | data = data << 1; | |
1578 | } | |
1579 | return (u8)(data >> 8); | |
1580 | } | |
1581 | ||
421ef47b JD |
1582 | /* Incremental CRC8 over count bytes in the array pointed to by p */ |
1583 | static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count) | |
1da177e4 LT |
1584 | { |
1585 | int i; | |
1586 | ||
7225acf4 | 1587 | for (i = 0; i < count; i++) |
421ef47b | 1588 | crc = crc8((crc ^ p[i]) << 8); |
1da177e4 LT |
1589 | return crc; |
1590 | } | |
1591 | ||
421ef47b JD |
1592 | /* Assume a 7-bit address, which is reasonable for SMBus */ |
1593 | static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg) | |
1da177e4 | 1594 | { |
421ef47b JD |
1595 | /* The address will be sent first */ |
1596 | u8 addr = (msg->addr << 1) | !!(msg->flags & I2C_M_RD); | |
1597 | pec = i2c_smbus_pec(pec, &addr, 1); | |
1598 | ||
1599 | /* The data buffer follows */ | |
1600 | return i2c_smbus_pec(pec, msg->buf, msg->len); | |
1da177e4 LT |
1601 | } |
1602 | ||
421ef47b JD |
1603 | /* Used for write only transactions */ |
1604 | static inline void i2c_smbus_add_pec(struct i2c_msg *msg) | |
1da177e4 | 1605 | { |
421ef47b JD |
1606 | msg->buf[msg->len] = i2c_smbus_msg_pec(0, msg); |
1607 | msg->len++; | |
1da177e4 LT |
1608 | } |
1609 | ||
421ef47b JD |
1610 | /* Return <0 on CRC error |
1611 | If there was a write before this read (most cases) we need to take the | |
1612 | partial CRC from the write part into account. | |
1613 | Note that this function does modify the message (we need to decrease the | |
1614 | message length to hide the CRC byte from the caller). */ | |
1615 | static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg) | |
1da177e4 | 1616 | { |
421ef47b JD |
1617 | u8 rpec = msg->buf[--msg->len]; |
1618 | cpec = i2c_smbus_msg_pec(cpec, msg); | |
1da177e4 | 1619 | |
1da177e4 LT |
1620 | if (rpec != cpec) { |
1621 | pr_debug("i2c-core: Bad PEC 0x%02x vs. 0x%02x\n", | |
1622 | rpec, cpec); | |
24a5bb7b | 1623 | return -EBADMSG; |
1da177e4 | 1624 | } |
438d6c2c | 1625 | return 0; |
1da177e4 LT |
1626 | } |
1627 | ||
a1cdedac DB |
1628 | /** |
1629 | * i2c_smbus_read_byte - SMBus "receive byte" protocol | |
1630 | * @client: Handle to slave device | |
1631 | * | |
1632 | * This executes the SMBus "receive byte" protocol, returning negative errno | |
1633 | * else the byte received from the device. | |
1634 | */ | |
1da177e4 LT |
1635 | s32 i2c_smbus_read_byte(struct i2c_client *client) |
1636 | { | |
1637 | union i2c_smbus_data data; | |
24a5bb7b DB |
1638 | int status; |
1639 | ||
1640 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1641 | I2C_SMBUS_READ, 0, | |
1642 | I2C_SMBUS_BYTE, &data); | |
1643 | return (status < 0) ? status : data.byte; | |
1da177e4 | 1644 | } |
c0564606 | 1645 | EXPORT_SYMBOL(i2c_smbus_read_byte); |
1da177e4 | 1646 | |
a1cdedac DB |
1647 | /** |
1648 | * i2c_smbus_write_byte - SMBus "send byte" protocol | |
1649 | * @client: Handle to slave device | |
1650 | * @value: Byte to be sent | |
1651 | * | |
1652 | * This executes the SMBus "send byte" protocol, returning negative errno | |
1653 | * else zero on success. | |
1654 | */ | |
1da177e4 LT |
1655 | s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value) |
1656 | { | |
7225acf4 | 1657 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
421ef47b | 1658 | I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL); |
1da177e4 | 1659 | } |
c0564606 | 1660 | EXPORT_SYMBOL(i2c_smbus_write_byte); |
1da177e4 | 1661 | |
a1cdedac DB |
1662 | /** |
1663 | * i2c_smbus_read_byte_data - SMBus "read byte" protocol | |
1664 | * @client: Handle to slave device | |
1665 | * @command: Byte interpreted by slave | |
1666 | * | |
1667 | * This executes the SMBus "read byte" protocol, returning negative errno | |
1668 | * else a data byte received from the device. | |
1669 | */ | |
1da177e4 LT |
1670 | s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command) |
1671 | { | |
1672 | union i2c_smbus_data data; | |
24a5bb7b DB |
1673 | int status; |
1674 | ||
1675 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1676 | I2C_SMBUS_READ, command, | |
1677 | I2C_SMBUS_BYTE_DATA, &data); | |
1678 | return (status < 0) ? status : data.byte; | |
1da177e4 | 1679 | } |
c0564606 | 1680 | EXPORT_SYMBOL(i2c_smbus_read_byte_data); |
1da177e4 | 1681 | |
a1cdedac DB |
1682 | /** |
1683 | * i2c_smbus_write_byte_data - SMBus "write byte" protocol | |
1684 | * @client: Handle to slave device | |
1685 | * @command: Byte interpreted by slave | |
1686 | * @value: Byte being written | |
1687 | * | |
1688 | * This executes the SMBus "write byte" protocol, returning negative errno | |
1689 | * else zero on success. | |
1690 | */ | |
1da177e4 LT |
1691 | s32 i2c_smbus_write_byte_data(struct i2c_client *client, u8 command, u8 value) |
1692 | { | |
1693 | union i2c_smbus_data data; | |
1694 | data.byte = value; | |
7225acf4 FH |
1695 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
1696 | I2C_SMBUS_WRITE, command, | |
1697 | I2C_SMBUS_BYTE_DATA, &data); | |
1da177e4 | 1698 | } |
c0564606 | 1699 | EXPORT_SYMBOL(i2c_smbus_write_byte_data); |
1da177e4 | 1700 | |
a1cdedac DB |
1701 | /** |
1702 | * i2c_smbus_read_word_data - SMBus "read word" protocol | |
1703 | * @client: Handle to slave device | |
1704 | * @command: Byte interpreted by slave | |
1705 | * | |
1706 | * This executes the SMBus "read word" protocol, returning negative errno | |
1707 | * else a 16-bit unsigned "word" received from the device. | |
1708 | */ | |
1da177e4 LT |
1709 | s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command) |
1710 | { | |
1711 | union i2c_smbus_data data; | |
24a5bb7b DB |
1712 | int status; |
1713 | ||
1714 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1715 | I2C_SMBUS_READ, command, | |
1716 | I2C_SMBUS_WORD_DATA, &data); | |
1717 | return (status < 0) ? status : data.word; | |
1da177e4 | 1718 | } |
c0564606 | 1719 | EXPORT_SYMBOL(i2c_smbus_read_word_data); |
1da177e4 | 1720 | |
a1cdedac DB |
1721 | /** |
1722 | * i2c_smbus_write_word_data - SMBus "write word" protocol | |
1723 | * @client: Handle to slave device | |
1724 | * @command: Byte interpreted by slave | |
1725 | * @value: 16-bit "word" being written | |
1726 | * | |
1727 | * This executes the SMBus "write word" protocol, returning negative errno | |
1728 | * else zero on success. | |
1729 | */ | |
1da177e4 LT |
1730 | s32 i2c_smbus_write_word_data(struct i2c_client *client, u8 command, u16 value) |
1731 | { | |
1732 | union i2c_smbus_data data; | |
1733 | data.word = value; | |
7225acf4 FH |
1734 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
1735 | I2C_SMBUS_WRITE, command, | |
1736 | I2C_SMBUS_WORD_DATA, &data); | |
1da177e4 | 1737 | } |
c0564606 | 1738 | EXPORT_SYMBOL(i2c_smbus_write_word_data); |
1da177e4 | 1739 | |
596c88f4 PM |
1740 | /** |
1741 | * i2c_smbus_process_call - SMBus "process call" protocol | |
1742 | * @client: Handle to slave device | |
1743 | * @command: Byte interpreted by slave | |
1744 | * @value: 16-bit "word" being written | |
1745 | * | |
1746 | * This executes the SMBus "process call" protocol, returning negative errno | |
1747 | * else a 16-bit unsigned "word" received from the device. | |
1748 | */ | |
1749 | s32 i2c_smbus_process_call(struct i2c_client *client, u8 command, u16 value) | |
1750 | { | |
1751 | union i2c_smbus_data data; | |
1752 | int status; | |
1753 | data.word = value; | |
1754 | ||
1755 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1756 | I2C_SMBUS_WRITE, command, | |
1757 | I2C_SMBUS_PROC_CALL, &data); | |
1758 | return (status < 0) ? status : data.word; | |
1759 | } | |
1760 | EXPORT_SYMBOL(i2c_smbus_process_call); | |
1761 | ||
a64ec07d | 1762 | /** |
a1cdedac | 1763 | * i2c_smbus_read_block_data - SMBus "block read" protocol |
a64ec07d | 1764 | * @client: Handle to slave device |
a1cdedac | 1765 | * @command: Byte interpreted by slave |
a64ec07d DB |
1766 | * @values: Byte array into which data will be read; big enough to hold |
1767 | * the data returned by the slave. SMBus allows at most 32 bytes. | |
1768 | * | |
a1cdedac DB |
1769 | * This executes the SMBus "block read" protocol, returning negative errno |
1770 | * else the number of data bytes in the slave's response. | |
a64ec07d DB |
1771 | * |
1772 | * Note that using this function requires that the client's adapter support | |
1773 | * the I2C_FUNC_SMBUS_READ_BLOCK_DATA functionality. Not all adapter drivers | |
1774 | * support this; its emulation through I2C messaging relies on a specific | |
1775 | * mechanism (I2C_M_RECV_LEN) which may not be implemented. | |
1776 | */ | |
b86a1bc8 JD |
1777 | s32 i2c_smbus_read_block_data(struct i2c_client *client, u8 command, |
1778 | u8 *values) | |
1779 | { | |
1780 | union i2c_smbus_data data; | |
24a5bb7b | 1781 | int status; |
b86a1bc8 | 1782 | |
24a5bb7b DB |
1783 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
1784 | I2C_SMBUS_READ, command, | |
1785 | I2C_SMBUS_BLOCK_DATA, &data); | |
1786 | if (status) | |
1787 | return status; | |
b86a1bc8 JD |
1788 | |
1789 | memcpy(values, &data.block[1], data.block[0]); | |
1790 | return data.block[0]; | |
1791 | } | |
1792 | EXPORT_SYMBOL(i2c_smbus_read_block_data); | |
1793 | ||
a1cdedac DB |
1794 | /** |
1795 | * i2c_smbus_write_block_data - SMBus "block write" protocol | |
1796 | * @client: Handle to slave device | |
1797 | * @command: Byte interpreted by slave | |
1798 | * @length: Size of data block; SMBus allows at most 32 bytes | |
1799 | * @values: Byte array which will be written. | |
1800 | * | |
1801 | * This executes the SMBus "block write" protocol, returning negative errno | |
1802 | * else zero on success. | |
1803 | */ | |
1da177e4 | 1804 | s32 i2c_smbus_write_block_data(struct i2c_client *client, u8 command, |
46f5ed75 | 1805 | u8 length, const u8 *values) |
1da177e4 LT |
1806 | { |
1807 | union i2c_smbus_data data; | |
7656032b | 1808 | |
1da177e4 LT |
1809 | if (length > I2C_SMBUS_BLOCK_MAX) |
1810 | length = I2C_SMBUS_BLOCK_MAX; | |
1da177e4 | 1811 | data.block[0] = length; |
7656032b | 1812 | memcpy(&data.block[1], values, length); |
7225acf4 FH |
1813 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
1814 | I2C_SMBUS_WRITE, command, | |
1815 | I2C_SMBUS_BLOCK_DATA, &data); | |
1da177e4 | 1816 | } |
c0564606 | 1817 | EXPORT_SYMBOL(i2c_smbus_write_block_data); |
1da177e4 LT |
1818 | |
1819 | /* Returns the number of read bytes */ | |
4b2643d7 JD |
1820 | s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client, u8 command, |
1821 | u8 length, u8 *values) | |
1da177e4 LT |
1822 | { |
1823 | union i2c_smbus_data data; | |
24a5bb7b | 1824 | int status; |
7656032b | 1825 | |
4b2643d7 JD |
1826 | if (length > I2C_SMBUS_BLOCK_MAX) |
1827 | length = I2C_SMBUS_BLOCK_MAX; | |
1828 | data.block[0] = length; | |
24a5bb7b DB |
1829 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
1830 | I2C_SMBUS_READ, command, | |
1831 | I2C_SMBUS_I2C_BLOCK_DATA, &data); | |
1832 | if (status < 0) | |
1833 | return status; | |
7656032b JD |
1834 | |
1835 | memcpy(values, &data.block[1], data.block[0]); | |
1836 | return data.block[0]; | |
1da177e4 | 1837 | } |
c0564606 | 1838 | EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data); |
1da177e4 | 1839 | |
21bbd691 | 1840 | s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client, u8 command, |
46f5ed75 | 1841 | u8 length, const u8 *values) |
21bbd691 JD |
1842 | { |
1843 | union i2c_smbus_data data; | |
1844 | ||
1845 | if (length > I2C_SMBUS_BLOCK_MAX) | |
1846 | length = I2C_SMBUS_BLOCK_MAX; | |
1847 | data.block[0] = length; | |
1848 | memcpy(data.block + 1, values, length); | |
1849 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1850 | I2C_SMBUS_WRITE, command, | |
1851 | I2C_SMBUS_I2C_BLOCK_DATA, &data); | |
1852 | } | |
c0564606 | 1853 | EXPORT_SYMBOL(i2c_smbus_write_i2c_block_data); |
21bbd691 | 1854 | |
438d6c2c | 1855 | /* Simulate a SMBus command using the i2c protocol |
1da177e4 | 1856 | No checking of parameters is done! */ |
7225acf4 FH |
1857 | static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, |
1858 | unsigned short flags, | |
1859 | char read_write, u8 command, int size, | |
1860 | union i2c_smbus_data *data) | |
1da177e4 LT |
1861 | { |
1862 | /* So we need to generate a series of msgs. In the case of writing, we | |
1863 | need to use only one message; when reading, we need two. We initialize | |
1864 | most things with sane defaults, to keep the code below somewhat | |
1865 | simpler. */ | |
5c50d188 HI |
1866 | unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3]; |
1867 | unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2]; | |
7225acf4 | 1868 | int num = read_write == I2C_SMBUS_READ ? 2 : 1; |
438d6c2c | 1869 | struct i2c_msg msg[2] = { { addr, flags, 1, msgbuf0 }, |
1da177e4 LT |
1870 | { addr, flags | I2C_M_RD, 0, msgbuf1 } |
1871 | }; | |
1872 | int i; | |
421ef47b | 1873 | u8 partial_pec = 0; |
24a5bb7b | 1874 | int status; |
1da177e4 LT |
1875 | |
1876 | msgbuf0[0] = command; | |
7225acf4 | 1877 | switch (size) { |
1da177e4 LT |
1878 | case I2C_SMBUS_QUICK: |
1879 | msg[0].len = 0; | |
1880 | /* Special case: The read/write field is used as data */ | |
f29d2e02 RK |
1881 | msg[0].flags = flags | (read_write == I2C_SMBUS_READ ? |
1882 | I2C_M_RD : 0); | |
1da177e4 LT |
1883 | num = 1; |
1884 | break; | |
1885 | case I2C_SMBUS_BYTE: | |
1886 | if (read_write == I2C_SMBUS_READ) { | |
1887 | /* Special case: only a read! */ | |
1888 | msg[0].flags = I2C_M_RD | flags; | |
1889 | num = 1; | |
1890 | } | |
1891 | break; | |
1892 | case I2C_SMBUS_BYTE_DATA: | |
1893 | if (read_write == I2C_SMBUS_READ) | |
1894 | msg[1].len = 1; | |
1895 | else { | |
1896 | msg[0].len = 2; | |
1897 | msgbuf0[1] = data->byte; | |
1898 | } | |
1899 | break; | |
1900 | case I2C_SMBUS_WORD_DATA: | |
1901 | if (read_write == I2C_SMBUS_READ) | |
1902 | msg[1].len = 2; | |
1903 | else { | |
7225acf4 | 1904 | msg[0].len = 3; |
1da177e4 | 1905 | msgbuf0[1] = data->word & 0xff; |
7eff82c8 | 1906 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
1907 | } |
1908 | break; | |
1909 | case I2C_SMBUS_PROC_CALL: | |
1910 | num = 2; /* Special case */ | |
1911 | read_write = I2C_SMBUS_READ; | |
1912 | msg[0].len = 3; | |
1913 | msg[1].len = 2; | |
1914 | msgbuf0[1] = data->word & 0xff; | |
7eff82c8 | 1915 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
1916 | break; |
1917 | case I2C_SMBUS_BLOCK_DATA: | |
1da177e4 | 1918 | if (read_write == I2C_SMBUS_READ) { |
209d27c3 JD |
1919 | msg[1].flags |= I2C_M_RECV_LEN; |
1920 | msg[1].len = 1; /* block length will be added by | |
1921 | the underlying bus driver */ | |
1da177e4 LT |
1922 | } else { |
1923 | msg[0].len = data->block[0] + 2; | |
1924 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 2) { | |
24a5bb7b DB |
1925 | dev_err(&adapter->dev, |
1926 | "Invalid block write size %d\n", | |
1927 | data->block[0]); | |
1928 | return -EINVAL; | |
1da177e4 | 1929 | } |
5c50d188 | 1930 | for (i = 1; i < msg[0].len; i++) |
1da177e4 LT |
1931 | msgbuf0[i] = data->block[i-1]; |
1932 | } | |
1933 | break; | |
1934 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
209d27c3 JD |
1935 | num = 2; /* Another special case */ |
1936 | read_write = I2C_SMBUS_READ; | |
1937 | if (data->block[0] > I2C_SMBUS_BLOCK_MAX) { | |
24a5bb7b DB |
1938 | dev_err(&adapter->dev, |
1939 | "Invalid block write size %d\n", | |
209d27c3 | 1940 | data->block[0]); |
24a5bb7b | 1941 | return -EINVAL; |
209d27c3 JD |
1942 | } |
1943 | msg[0].len = data->block[0] + 2; | |
1944 | for (i = 1; i < msg[0].len; i++) | |
1945 | msgbuf0[i] = data->block[i-1]; | |
1946 | msg[1].flags |= I2C_M_RECV_LEN; | |
1947 | msg[1].len = 1; /* block length will be added by | |
1948 | the underlying bus driver */ | |
1949 | break; | |
1da177e4 LT |
1950 | case I2C_SMBUS_I2C_BLOCK_DATA: |
1951 | if (read_write == I2C_SMBUS_READ) { | |
4b2643d7 | 1952 | msg[1].len = data->block[0]; |
1da177e4 LT |
1953 | } else { |
1954 | msg[0].len = data->block[0] + 1; | |
30dac746 | 1955 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 1) { |
24a5bb7b DB |
1956 | dev_err(&adapter->dev, |
1957 | "Invalid block write size %d\n", | |
1958 | data->block[0]); | |
1959 | return -EINVAL; | |
1da177e4 LT |
1960 | } |
1961 | for (i = 1; i <= data->block[0]; i++) | |
1962 | msgbuf0[i] = data->block[i]; | |
1963 | } | |
1964 | break; | |
1965 | default: | |
24a5bb7b DB |
1966 | dev_err(&adapter->dev, "Unsupported transaction %d\n", size); |
1967 | return -EOPNOTSUPP; | |
1da177e4 LT |
1968 | } |
1969 | ||
421ef47b JD |
1970 | i = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK |
1971 | && size != I2C_SMBUS_I2C_BLOCK_DATA); | |
1972 | if (i) { | |
1973 | /* Compute PEC if first message is a write */ | |
1974 | if (!(msg[0].flags & I2C_M_RD)) { | |
438d6c2c | 1975 | if (num == 1) /* Write only */ |
421ef47b JD |
1976 | i2c_smbus_add_pec(&msg[0]); |
1977 | else /* Write followed by read */ | |
1978 | partial_pec = i2c_smbus_msg_pec(0, &msg[0]); | |
1979 | } | |
1980 | /* Ask for PEC if last message is a read */ | |
1981 | if (msg[num-1].flags & I2C_M_RD) | |
438d6c2c | 1982 | msg[num-1].len++; |
421ef47b JD |
1983 | } |
1984 | ||
24a5bb7b DB |
1985 | status = i2c_transfer(adapter, msg, num); |
1986 | if (status < 0) | |
1987 | return status; | |
1da177e4 | 1988 | |
421ef47b JD |
1989 | /* Check PEC if last message is a read */ |
1990 | if (i && (msg[num-1].flags & I2C_M_RD)) { | |
24a5bb7b DB |
1991 | status = i2c_smbus_check_pec(partial_pec, &msg[num-1]); |
1992 | if (status < 0) | |
1993 | return status; | |
421ef47b JD |
1994 | } |
1995 | ||
1da177e4 | 1996 | if (read_write == I2C_SMBUS_READ) |
7225acf4 FH |
1997 | switch (size) { |
1998 | case I2C_SMBUS_BYTE: | |
1999 | data->byte = msgbuf0[0]; | |
2000 | break; | |
2001 | case I2C_SMBUS_BYTE_DATA: | |
2002 | data->byte = msgbuf1[0]; | |
2003 | break; | |
2004 | case I2C_SMBUS_WORD_DATA: | |
2005 | case I2C_SMBUS_PROC_CALL: | |
2006 | data->word = msgbuf1[0] | (msgbuf1[1] << 8); | |
2007 | break; | |
2008 | case I2C_SMBUS_I2C_BLOCK_DATA: | |
2009 | for (i = 0; i < data->block[0]; i++) | |
2010 | data->block[i+1] = msgbuf1[i]; | |
2011 | break; | |
2012 | case I2C_SMBUS_BLOCK_DATA: | |
2013 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
2014 | for (i = 0; i < msgbuf1[0] + 1; i++) | |
2015 | data->block[i] = msgbuf1[i]; | |
2016 | break; | |
1da177e4 LT |
2017 | } |
2018 | return 0; | |
2019 | } | |
2020 | ||
a1cdedac DB |
2021 | /** |
2022 | * i2c_smbus_xfer - execute SMBus protocol operations | |
2023 | * @adapter: Handle to I2C bus | |
2024 | * @addr: Address of SMBus slave on that bus | |
2025 | * @flags: I2C_CLIENT_* flags (usually zero or I2C_CLIENT_PEC) | |
2026 | * @read_write: I2C_SMBUS_READ or I2C_SMBUS_WRITE | |
2027 | * @command: Byte interpreted by slave, for protocols which use such bytes | |
2028 | * @protocol: SMBus protocol operation to execute, such as I2C_SMBUS_PROC_CALL | |
2029 | * @data: Data to be read or written | |
2030 | * | |
2031 | * This executes an SMBus protocol operation, and returns a negative | |
2032 | * errno code else zero on success. | |
2033 | */ | |
09b8ce0a | 2034 | s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags, |
a1cdedac | 2035 | char read_write, u8 command, int protocol, |
09b8ce0a | 2036 | union i2c_smbus_data *data) |
1da177e4 | 2037 | { |
66b650f0 CW |
2038 | unsigned long orig_jiffies; |
2039 | int try; | |
1da177e4 | 2040 | s32 res; |
1da177e4 LT |
2041 | |
2042 | flags &= I2C_M_TEN | I2C_CLIENT_PEC; | |
1da177e4 LT |
2043 | |
2044 | if (adapter->algo->smbus_xfer) { | |
fe61e07e | 2045 | i2c_lock_adapter(adapter); |
66b650f0 CW |
2046 | |
2047 | /* Retry automatically on arbitration loss */ | |
2048 | orig_jiffies = jiffies; | |
2049 | for (res = 0, try = 0; try <= adapter->retries; try++) { | |
2050 | res = adapter->algo->smbus_xfer(adapter, addr, flags, | |
2051 | read_write, command, | |
2052 | protocol, data); | |
2053 | if (res != -EAGAIN) | |
2054 | break; | |
2055 | if (time_after(jiffies, | |
2056 | orig_jiffies + adapter->timeout)) | |
2057 | break; | |
2058 | } | |
fe61e07e | 2059 | i2c_unlock_adapter(adapter); |
1da177e4 | 2060 | } else |
7225acf4 | 2061 | res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write, |
a1cdedac | 2062 | command, protocol, data); |
1da177e4 | 2063 | |
1da177e4 LT |
2064 | return res; |
2065 | } | |
1da177e4 | 2066 | EXPORT_SYMBOL(i2c_smbus_xfer); |
1da177e4 LT |
2067 | |
2068 | MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); | |
2069 | MODULE_DESCRIPTION("I2C-Bus main module"); | |
2070 | MODULE_LICENSE("GPL"); |