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 | 22 | SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and |
0826374b ML |
23 | Jean Delvare <khali@linux-fr.org> |
24 | Mux support by Rodolfo Giometti <giometti@enneenne.com> and | |
25 | Michael Lawnick <michael.lawnick.ext@nsn.com> */ | |
1da177e4 | 26 | |
1da177e4 LT |
27 | #include <linux/module.h> |
28 | #include <linux/kernel.h> | |
29 | #include <linux/errno.h> | |
30 | #include <linux/slab.h> | |
31 | #include <linux/i2c.h> | |
32 | #include <linux/init.h> | |
33 | #include <linux/idr.h> | |
b3585e4f | 34 | #include <linux/mutex.h> |
959e85f7 | 35 | #include <linux/of_device.h> |
b8d6f45b | 36 | #include <linux/completion.h> |
cea443a8 MR |
37 | #include <linux/hardirq.h> |
38 | #include <linux/irqflags.h> | |
f18c41da | 39 | #include <linux/rwsem.h> |
6de468ae | 40 | #include <linux/pm_runtime.h> |
1da177e4 LT |
41 | #include <asm/uaccess.h> |
42 | ||
9c1600ed DB |
43 | #include "i2c-core.h" |
44 | ||
1da177e4 | 45 | |
6629dcff | 46 | /* core_lock protects i2c_adapter_idr, and guarantees |
35fc37f8 JD |
47 | that device detection, deletion of detected devices, and attach_adapter |
48 | and detach_adapter calls are serialized */ | |
caada32a | 49 | static DEFINE_MUTEX(core_lock); |
1da177e4 LT |
50 | static DEFINE_IDR(i2c_adapter_idr); |
51 | ||
4f8cf824 | 52 | static struct device_type i2c_client_type; |
4735c98f | 53 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver); |
f37dd80a DB |
54 | |
55 | /* ------------------------------------------------------------------------- */ | |
56 | ||
d2653e92 JD |
57 | static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, |
58 | const struct i2c_client *client) | |
59 | { | |
60 | while (id->name[0]) { | |
61 | if (strcmp(client->name, id->name) == 0) | |
62 | return id; | |
63 | id++; | |
64 | } | |
65 | return NULL; | |
66 | } | |
67 | ||
1da177e4 LT |
68 | static int i2c_device_match(struct device *dev, struct device_driver *drv) |
69 | { | |
51298d12 JD |
70 | struct i2c_client *client = i2c_verify_client(dev); |
71 | struct i2c_driver *driver; | |
72 | ||
73 | if (!client) | |
74 | return 0; | |
7b4fbc50 | 75 | |
959e85f7 GL |
76 | /* Attempt an OF style match */ |
77 | if (of_driver_match_device(dev, drv)) | |
78 | return 1; | |
79 | ||
51298d12 | 80 | driver = to_i2c_driver(drv); |
d2653e92 JD |
81 | /* match on an id table if there is one */ |
82 | if (driver->id_table) | |
83 | return i2c_match_id(driver->id_table, client) != NULL; | |
84 | ||
eb8a7908 | 85 | return 0; |
1da177e4 LT |
86 | } |
87 | ||
7b4fbc50 DB |
88 | #ifdef CONFIG_HOTPLUG |
89 | ||
90 | /* uevent helps with hotplug: modprobe -q $(MODALIAS) */ | |
7eff2e7a | 91 | static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env) |
7b4fbc50 DB |
92 | { |
93 | struct i2c_client *client = to_i2c_client(dev); | |
7b4fbc50 | 94 | |
eb8a7908 JD |
95 | if (add_uevent_var(env, "MODALIAS=%s%s", |
96 | I2C_MODULE_PREFIX, client->name)) | |
97 | return -ENOMEM; | |
7b4fbc50 DB |
98 | dev_dbg(dev, "uevent\n"); |
99 | return 0; | |
100 | } | |
101 | ||
102 | #else | |
103 | #define i2c_device_uevent NULL | |
104 | #endif /* CONFIG_HOTPLUG */ | |
105 | ||
f37dd80a | 106 | static int i2c_device_probe(struct device *dev) |
1da177e4 | 107 | { |
51298d12 JD |
108 | struct i2c_client *client = i2c_verify_client(dev); |
109 | struct i2c_driver *driver; | |
50c3304a | 110 | int status; |
7b4fbc50 | 111 | |
51298d12 JD |
112 | if (!client) |
113 | return 0; | |
114 | ||
115 | driver = to_i2c_driver(dev->driver); | |
e0457442 | 116 | if (!driver->probe || !driver->id_table) |
7b4fbc50 DB |
117 | return -ENODEV; |
118 | client->driver = driver; | |
ee35425c MP |
119 | if (!device_can_wakeup(&client->dev)) |
120 | device_init_wakeup(&client->dev, | |
121 | client->flags & I2C_CLIENT_WAKE); | |
7b4fbc50 | 122 | dev_dbg(dev, "probe\n"); |
d2653e92 | 123 | |
e0457442 | 124 | status = driver->probe(client, i2c_match_id(driver->id_table, client)); |
e4a7b9b0 | 125 | if (status) { |
50c3304a | 126 | client->driver = NULL; |
e4a7b9b0 WS |
127 | i2c_set_clientdata(client, NULL); |
128 | } | |
50c3304a | 129 | return status; |
f37dd80a | 130 | } |
1da177e4 | 131 | |
f37dd80a DB |
132 | static int i2c_device_remove(struct device *dev) |
133 | { | |
51298d12 | 134 | struct i2c_client *client = i2c_verify_client(dev); |
a1d9e6e4 DB |
135 | struct i2c_driver *driver; |
136 | int status; | |
137 | ||
51298d12 | 138 | if (!client || !dev->driver) |
a1d9e6e4 DB |
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 | } | |
e4a7b9b0 | 149 | if (status == 0) { |
a1d9e6e4 | 150 | client->driver = NULL; |
e4a7b9b0 WS |
151 | i2c_set_clientdata(client, NULL); |
152 | } | |
a1d9e6e4 | 153 | return status; |
1da177e4 LT |
154 | } |
155 | ||
f37dd80a | 156 | static void i2c_device_shutdown(struct device *dev) |
1da177e4 | 157 | { |
51298d12 | 158 | struct i2c_client *client = i2c_verify_client(dev); |
f37dd80a DB |
159 | struct i2c_driver *driver; |
160 | ||
51298d12 | 161 | if (!client || !dev->driver) |
f37dd80a DB |
162 | return; |
163 | driver = to_i2c_driver(dev->driver); | |
164 | if (driver->shutdown) | |
51298d12 | 165 | driver->shutdown(client); |
1da177e4 LT |
166 | } |
167 | ||
2f60ba70 RW |
168 | #ifdef CONFIG_PM_SLEEP |
169 | static int i2c_legacy_suspend(struct device *dev, pm_message_t mesg) | |
54067ee2 | 170 | { |
2f60ba70 RW |
171 | struct i2c_client *client = i2c_verify_client(dev); |
172 | struct i2c_driver *driver; | |
54067ee2 | 173 | |
2f60ba70 | 174 | if (!client || !dev->driver) |
54067ee2 | 175 | return 0; |
2f60ba70 RW |
176 | driver = to_i2c_driver(dev->driver); |
177 | if (!driver->suspend) | |
54067ee2 | 178 | return 0; |
2f60ba70 | 179 | return driver->suspend(client, mesg); |
54067ee2 | 180 | } |
181 | ||
2f60ba70 | 182 | static int i2c_legacy_resume(struct device *dev) |
54067ee2 | 183 | { |
2f60ba70 RW |
184 | struct i2c_client *client = i2c_verify_client(dev); |
185 | struct i2c_driver *driver; | |
54067ee2 | 186 | |
2f60ba70 | 187 | if (!client || !dev->driver) |
54067ee2 | 188 | return 0; |
2f60ba70 RW |
189 | driver = to_i2c_driver(dev->driver); |
190 | if (!driver->resume) | |
54067ee2 | 191 | return 0; |
2f60ba70 | 192 | return driver->resume(client); |
54067ee2 | 193 | } |
54067ee2 | 194 | |
2f60ba70 | 195 | static int i2c_device_pm_suspend(struct device *dev) |
6de468ae | 196 | { |
2f60ba70 | 197 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
6de468ae | 198 | |
d529de29 MB |
199 | if (pm) |
200 | return pm_generic_suspend(dev); | |
201 | else | |
202 | return i2c_legacy_suspend(dev, PMSG_SUSPEND); | |
6de468ae MB |
203 | } |
204 | ||
2f60ba70 | 205 | static int i2c_device_pm_resume(struct device *dev) |
6de468ae | 206 | { |
2f60ba70 | 207 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
6de468ae | 208 | |
2f60ba70 | 209 | if (pm) |
d529de29 | 210 | return pm_generic_resume(dev); |
2f60ba70 | 211 | else |
d529de29 | 212 | return i2c_legacy_resume(dev); |
6de468ae | 213 | } |
6de468ae | 214 | |
2f60ba70 | 215 | static int i2c_device_pm_freeze(struct device *dev) |
1da177e4 | 216 | { |
2f60ba70 | 217 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
f37dd80a | 218 | |
d529de29 MB |
219 | if (pm) |
220 | return pm_generic_freeze(dev); | |
221 | else | |
222 | return i2c_legacy_suspend(dev, PMSG_FREEZE); | |
1da177e4 LT |
223 | } |
224 | ||
2f60ba70 | 225 | static int i2c_device_pm_thaw(struct device *dev) |
1da177e4 | 226 | { |
2f60ba70 | 227 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
f37dd80a | 228 | |
d529de29 MB |
229 | if (pm) |
230 | return pm_generic_thaw(dev); | |
231 | else | |
232 | return i2c_legacy_resume(dev); | |
2f60ba70 RW |
233 | } |
234 | ||
235 | static int i2c_device_pm_poweroff(struct device *dev) | |
236 | { | |
237 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; | |
238 | ||
d529de29 MB |
239 | if (pm) |
240 | return pm_generic_poweroff(dev); | |
241 | else | |
242 | return i2c_legacy_suspend(dev, PMSG_HIBERNATE); | |
2f60ba70 RW |
243 | } |
244 | ||
245 | static int i2c_device_pm_restore(struct device *dev) | |
246 | { | |
247 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; | |
2f60ba70 RW |
248 | |
249 | if (pm) | |
d529de29 | 250 | return pm_generic_restore(dev); |
2f60ba70 | 251 | else |
d529de29 | 252 | return i2c_legacy_resume(dev); |
1da177e4 | 253 | } |
2f60ba70 RW |
254 | #else /* !CONFIG_PM_SLEEP */ |
255 | #define i2c_device_pm_suspend NULL | |
256 | #define i2c_device_pm_resume NULL | |
257 | #define i2c_device_pm_freeze NULL | |
258 | #define i2c_device_pm_thaw NULL | |
259 | #define i2c_device_pm_poweroff NULL | |
260 | #define i2c_device_pm_restore NULL | |
261 | #endif /* !CONFIG_PM_SLEEP */ | |
1da177e4 | 262 | |
9c1600ed DB |
263 | static void i2c_client_dev_release(struct device *dev) |
264 | { | |
265 | kfree(to_i2c_client(dev)); | |
266 | } | |
267 | ||
09b8ce0a | 268 | static ssize_t |
4f8cf824 | 269 | show_name(struct device *dev, struct device_attribute *attr, char *buf) |
7b4fbc50 | 270 | { |
4f8cf824 JD |
271 | return sprintf(buf, "%s\n", dev->type == &i2c_client_type ? |
272 | to_i2c_client(dev)->name : to_i2c_adapter(dev)->name); | |
7b4fbc50 DB |
273 | } |
274 | ||
09b8ce0a ZX |
275 | static ssize_t |
276 | show_modalias(struct device *dev, struct device_attribute *attr, char *buf) | |
7b4fbc50 DB |
277 | { |
278 | struct i2c_client *client = to_i2c_client(dev); | |
eb8a7908 | 279 | return sprintf(buf, "%s%s\n", I2C_MODULE_PREFIX, client->name); |
7b4fbc50 DB |
280 | } |
281 | ||
4f8cf824 | 282 | static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); |
51298d12 JD |
283 | static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL); |
284 | ||
285 | static struct attribute *i2c_dev_attrs[] = { | |
286 | &dev_attr_name.attr, | |
7b4fbc50 | 287 | /* modalias helps coldplug: modprobe $(cat .../modalias) */ |
51298d12 JD |
288 | &dev_attr_modalias.attr, |
289 | NULL | |
290 | }; | |
291 | ||
292 | static struct attribute_group i2c_dev_attr_group = { | |
293 | .attrs = i2c_dev_attrs, | |
294 | }; | |
295 | ||
296 | static const struct attribute_group *i2c_dev_attr_groups[] = { | |
297 | &i2c_dev_attr_group, | |
298 | NULL | |
7b4fbc50 DB |
299 | }; |
300 | ||
0b2c3688 | 301 | static const struct dev_pm_ops i2c_device_pm_ops = { |
54067ee2 | 302 | .suspend = i2c_device_pm_suspend, |
303 | .resume = i2c_device_pm_resume, | |
2f60ba70 RW |
304 | .freeze = i2c_device_pm_freeze, |
305 | .thaw = i2c_device_pm_thaw, | |
306 | .poweroff = i2c_device_pm_poweroff, | |
307 | .restore = i2c_device_pm_restore, | |
308 | SET_RUNTIME_PM_OPS( | |
309 | pm_generic_runtime_suspend, | |
310 | pm_generic_runtime_resume, | |
311 | pm_generic_runtime_idle | |
312 | ) | |
54067ee2 | 313 | }; |
314 | ||
e9ca9eb9 | 315 | struct bus_type i2c_bus_type = { |
f37dd80a DB |
316 | .name = "i2c", |
317 | .match = i2c_device_match, | |
318 | .probe = i2c_device_probe, | |
319 | .remove = i2c_device_remove, | |
320 | .shutdown = i2c_device_shutdown, | |
54067ee2 | 321 | .pm = &i2c_device_pm_ops, |
b864c7d5 | 322 | }; |
e9ca9eb9 | 323 | EXPORT_SYMBOL_GPL(i2c_bus_type); |
b864c7d5 | 324 | |
51298d12 JD |
325 | static struct device_type i2c_client_type = { |
326 | .groups = i2c_dev_attr_groups, | |
327 | .uevent = i2c_device_uevent, | |
328 | .release = i2c_client_dev_release, | |
329 | }; | |
330 | ||
9b766b81 DB |
331 | |
332 | /** | |
333 | * i2c_verify_client - return parameter as i2c_client, or NULL | |
334 | * @dev: device, probably from some driver model iterator | |
335 | * | |
336 | * When traversing the driver model tree, perhaps using driver model | |
337 | * iterators like @device_for_each_child(), you can't assume very much | |
338 | * about the nodes you find. Use this function to avoid oopses caused | |
339 | * by wrongly treating some non-I2C device as an i2c_client. | |
340 | */ | |
341 | struct i2c_client *i2c_verify_client(struct device *dev) | |
342 | { | |
51298d12 | 343 | return (dev->type == &i2c_client_type) |
9b766b81 DB |
344 | ? to_i2c_client(dev) |
345 | : NULL; | |
346 | } | |
347 | EXPORT_SYMBOL(i2c_verify_client); | |
348 | ||
349 | ||
3a89db5f | 350 | /* This is a permissive address validity check, I2C address map constraints |
25985edc | 351 | * are purposely not enforced, except for the general call address. */ |
3a89db5f JD |
352 | static int i2c_check_client_addr_validity(const struct i2c_client *client) |
353 | { | |
354 | if (client->flags & I2C_CLIENT_TEN) { | |
355 | /* 10-bit address, all values are valid */ | |
356 | if (client->addr > 0x3ff) | |
357 | return -EINVAL; | |
358 | } else { | |
359 | /* 7-bit address, reject the general call address */ | |
360 | if (client->addr == 0x00 || client->addr > 0x7f) | |
361 | return -EINVAL; | |
362 | } | |
363 | return 0; | |
364 | } | |
365 | ||
656b8761 JD |
366 | /* And this is a strict address validity check, used when probing. If a |
367 | * device uses a reserved address, then it shouldn't be probed. 7-bit | |
368 | * addressing is assumed, 10-bit address devices are rare and should be | |
369 | * explicitly enumerated. */ | |
370 | static int i2c_check_addr_validity(unsigned short addr) | |
371 | { | |
372 | /* | |
373 | * Reserved addresses per I2C specification: | |
374 | * 0x00 General call address / START byte | |
375 | * 0x01 CBUS address | |
376 | * 0x02 Reserved for different bus format | |
377 | * 0x03 Reserved for future purposes | |
378 | * 0x04-0x07 Hs-mode master code | |
379 | * 0x78-0x7b 10-bit slave addressing | |
380 | * 0x7c-0x7f Reserved for future purposes | |
381 | */ | |
382 | if (addr < 0x08 || addr > 0x77) | |
383 | return -EINVAL; | |
384 | return 0; | |
385 | } | |
386 | ||
3b5f794b JD |
387 | static int __i2c_check_addr_busy(struct device *dev, void *addrp) |
388 | { | |
389 | struct i2c_client *client = i2c_verify_client(dev); | |
390 | int addr = *(int *)addrp; | |
391 | ||
392 | if (client && client->addr == addr) | |
393 | return -EBUSY; | |
394 | return 0; | |
395 | } | |
396 | ||
0826374b ML |
397 | /* walk up mux tree */ |
398 | static int i2c_check_mux_parents(struct i2c_adapter *adapter, int addr) | |
399 | { | |
97cc4d49 | 400 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
0826374b ML |
401 | int result; |
402 | ||
403 | result = device_for_each_child(&adapter->dev, &addr, | |
404 | __i2c_check_addr_busy); | |
405 | ||
97cc4d49 JD |
406 | if (!result && parent) |
407 | result = i2c_check_mux_parents(parent, addr); | |
0826374b ML |
408 | |
409 | return result; | |
410 | } | |
411 | ||
412 | /* recurse down mux tree */ | |
413 | static int i2c_check_mux_children(struct device *dev, void *addrp) | |
414 | { | |
415 | int result; | |
416 | ||
417 | if (dev->type == &i2c_adapter_type) | |
418 | result = device_for_each_child(dev, addrp, | |
419 | i2c_check_mux_children); | |
420 | else | |
421 | result = __i2c_check_addr_busy(dev, addrp); | |
422 | ||
423 | return result; | |
424 | } | |
425 | ||
3b5f794b JD |
426 | static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr) |
427 | { | |
97cc4d49 | 428 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
0826374b ML |
429 | int result = 0; |
430 | ||
97cc4d49 JD |
431 | if (parent) |
432 | result = i2c_check_mux_parents(parent, addr); | |
0826374b ML |
433 | |
434 | if (!result) | |
435 | result = device_for_each_child(&adapter->dev, &addr, | |
436 | i2c_check_mux_children); | |
437 | ||
438 | return result; | |
3b5f794b JD |
439 | } |
440 | ||
fe61e07e JD |
441 | /** |
442 | * i2c_lock_adapter - Get exclusive access to an I2C bus segment | |
443 | * @adapter: Target I2C bus segment | |
444 | */ | |
445 | void i2c_lock_adapter(struct i2c_adapter *adapter) | |
446 | { | |
97cc4d49 JD |
447 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
448 | ||
449 | if (parent) | |
450 | i2c_lock_adapter(parent); | |
0826374b ML |
451 | else |
452 | rt_mutex_lock(&adapter->bus_lock); | |
fe61e07e JD |
453 | } |
454 | EXPORT_SYMBOL_GPL(i2c_lock_adapter); | |
455 | ||
456 | /** | |
457 | * i2c_trylock_adapter - Try to get exclusive access to an I2C bus segment | |
458 | * @adapter: Target I2C bus segment | |
459 | */ | |
460 | static int i2c_trylock_adapter(struct i2c_adapter *adapter) | |
461 | { | |
97cc4d49 JD |
462 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
463 | ||
464 | if (parent) | |
465 | return i2c_trylock_adapter(parent); | |
0826374b ML |
466 | else |
467 | return rt_mutex_trylock(&adapter->bus_lock); | |
fe61e07e JD |
468 | } |
469 | ||
470 | /** | |
471 | * i2c_unlock_adapter - Release exclusive access to an I2C bus segment | |
472 | * @adapter: Target I2C bus segment | |
473 | */ | |
474 | void i2c_unlock_adapter(struct i2c_adapter *adapter) | |
475 | { | |
97cc4d49 JD |
476 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
477 | ||
478 | if (parent) | |
479 | i2c_unlock_adapter(parent); | |
0826374b ML |
480 | else |
481 | rt_mutex_unlock(&adapter->bus_lock); | |
fe61e07e JD |
482 | } |
483 | EXPORT_SYMBOL_GPL(i2c_unlock_adapter); | |
484 | ||
9c1600ed | 485 | /** |
f8a227e8 | 486 | * i2c_new_device - instantiate an i2c device |
9c1600ed DB |
487 | * @adap: the adapter managing the device |
488 | * @info: describes one I2C device; bus_num is ignored | |
d64f73be | 489 | * Context: can sleep |
9c1600ed | 490 | * |
f8a227e8 JD |
491 | * Create an i2c device. Binding is handled through driver model |
492 | * probe()/remove() methods. A driver may be bound to this device when we | |
493 | * return from this function, or any later moment (e.g. maybe hotplugging will | |
494 | * load the driver module). This call is not appropriate for use by mainboard | |
495 | * initialization logic, which usually runs during an arch_initcall() long | |
496 | * before any i2c_adapter could exist. | |
9c1600ed DB |
497 | * |
498 | * This returns the new i2c client, which may be saved for later use with | |
499 | * i2c_unregister_device(); or NULL to indicate an error. | |
500 | */ | |
501 | struct i2c_client * | |
502 | i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) | |
503 | { | |
504 | struct i2c_client *client; | |
505 | int status; | |
506 | ||
507 | client = kzalloc(sizeof *client, GFP_KERNEL); | |
508 | if (!client) | |
509 | return NULL; | |
510 | ||
511 | client->adapter = adap; | |
512 | ||
513 | client->dev.platform_data = info->platform_data; | |
3bbb835d | 514 | |
11f1f2af AV |
515 | if (info->archdata) |
516 | client->dev.archdata = *info->archdata; | |
517 | ||
ee35425c | 518 | client->flags = info->flags; |
9c1600ed DB |
519 | client->addr = info->addr; |
520 | client->irq = info->irq; | |
521 | ||
9c1600ed DB |
522 | strlcpy(client->name, info->type, sizeof(client->name)); |
523 | ||
3a89db5f JD |
524 | /* Check for address validity */ |
525 | status = i2c_check_client_addr_validity(client); | |
526 | if (status) { | |
527 | dev_err(&adap->dev, "Invalid %d-bit I2C address 0x%02hx\n", | |
528 | client->flags & I2C_CLIENT_TEN ? 10 : 7, client->addr); | |
529 | goto out_err_silent; | |
530 | } | |
531 | ||
f8a227e8 | 532 | /* Check for address business */ |
3b5f794b | 533 | status = i2c_check_addr_busy(adap, client->addr); |
f8a227e8 JD |
534 | if (status) |
535 | goto out_err; | |
536 | ||
537 | client->dev.parent = &client->adapter->dev; | |
538 | client->dev.bus = &i2c_bus_type; | |
51298d12 | 539 | client->dev.type = &i2c_client_type; |
d12d42f7 | 540 | client->dev.of_node = info->of_node; |
f8a227e8 | 541 | |
cbb44514 | 542 | /* For 10-bit clients, add an arbitrary offset to avoid collisions */ |
f8a227e8 | 543 | dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap), |
cbb44514 JD |
544 | client->addr | ((client->flags & I2C_CLIENT_TEN) |
545 | ? 0xa000 : 0)); | |
f8a227e8 JD |
546 | status = device_register(&client->dev); |
547 | if (status) | |
548 | goto out_err; | |
549 | ||
f8a227e8 JD |
550 | dev_dbg(&adap->dev, "client [%s] registered with bus id %s\n", |
551 | client->name, dev_name(&client->dev)); | |
552 | ||
9c1600ed | 553 | return client; |
f8a227e8 JD |
554 | |
555 | out_err: | |
556 | dev_err(&adap->dev, "Failed to register i2c client %s at 0x%02x " | |
557 | "(%d)\n", client->name, client->addr, status); | |
3a89db5f | 558 | out_err_silent: |
f8a227e8 JD |
559 | kfree(client); |
560 | return NULL; | |
9c1600ed DB |
561 | } |
562 | EXPORT_SYMBOL_GPL(i2c_new_device); | |
563 | ||
564 | ||
565 | /** | |
566 | * i2c_unregister_device - reverse effect of i2c_new_device() | |
567 | * @client: value returned from i2c_new_device() | |
d64f73be | 568 | * Context: can sleep |
9c1600ed DB |
569 | */ |
570 | void i2c_unregister_device(struct i2c_client *client) | |
a1d9e6e4 | 571 | { |
a1d9e6e4 DB |
572 | device_unregister(&client->dev); |
573 | } | |
9c1600ed | 574 | EXPORT_SYMBOL_GPL(i2c_unregister_device); |
a1d9e6e4 DB |
575 | |
576 | ||
60b129d7 JD |
577 | static const struct i2c_device_id dummy_id[] = { |
578 | { "dummy", 0 }, | |
579 | { }, | |
580 | }; | |
581 | ||
d2653e92 JD |
582 | static int dummy_probe(struct i2c_client *client, |
583 | const struct i2c_device_id *id) | |
584 | { | |
585 | return 0; | |
586 | } | |
587 | ||
588 | static int dummy_remove(struct i2c_client *client) | |
e9f1373b DB |
589 | { |
590 | return 0; | |
591 | } | |
592 | ||
593 | static struct i2c_driver dummy_driver = { | |
594 | .driver.name = "dummy", | |
d2653e92 JD |
595 | .probe = dummy_probe, |
596 | .remove = dummy_remove, | |
60b129d7 | 597 | .id_table = dummy_id, |
e9f1373b DB |
598 | }; |
599 | ||
600 | /** | |
601 | * i2c_new_dummy - return a new i2c device bound to a dummy driver | |
602 | * @adapter: the adapter managing the device | |
603 | * @address: seven bit address to be used | |
e9f1373b DB |
604 | * Context: can sleep |
605 | * | |
606 | * This returns an I2C client bound to the "dummy" driver, intended for use | |
607 | * with devices that consume multiple addresses. Examples of such chips | |
608 | * include various EEPROMS (like 24c04 and 24c08 models). | |
609 | * | |
610 | * These dummy devices have two main uses. First, most I2C and SMBus calls | |
611 | * except i2c_transfer() need a client handle; the dummy will be that handle. | |
612 | * And second, this prevents the specified address from being bound to a | |
613 | * different driver. | |
614 | * | |
615 | * This returns the new i2c client, which should be saved for later use with | |
616 | * i2c_unregister_device(); or NULL to indicate an error. | |
617 | */ | |
09b8ce0a | 618 | struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) |
e9f1373b DB |
619 | { |
620 | struct i2c_board_info info = { | |
60b129d7 | 621 | I2C_BOARD_INFO("dummy", address), |
e9f1373b DB |
622 | }; |
623 | ||
e9f1373b DB |
624 | return i2c_new_device(adapter, &info); |
625 | } | |
626 | EXPORT_SYMBOL_GPL(i2c_new_dummy); | |
627 | ||
f37dd80a DB |
628 | /* ------------------------------------------------------------------------- */ |
629 | ||
16ffadfc DB |
630 | /* I2C bus adapters -- one roots each I2C or SMBUS segment */ |
631 | ||
83eaaed0 | 632 | static void i2c_adapter_dev_release(struct device *dev) |
1da177e4 | 633 | { |
ef2c8321 | 634 | struct i2c_adapter *adap = to_i2c_adapter(dev); |
1da177e4 LT |
635 | complete(&adap->dev_released); |
636 | } | |
637 | ||
99cd8e25 JD |
638 | /* |
639 | * Let users instantiate I2C devices through sysfs. This can be used when | |
640 | * platform initialization code doesn't contain the proper data for | |
641 | * whatever reason. Also useful for drivers that do device detection and | |
642 | * detection fails, either because the device uses an unexpected address, | |
643 | * or this is a compatible device with different ID register values. | |
644 | * | |
645 | * Parameter checking may look overzealous, but we really don't want | |
646 | * the user to provide incorrect parameters. | |
647 | */ | |
648 | static ssize_t | |
649 | i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr, | |
650 | const char *buf, size_t count) | |
651 | { | |
652 | struct i2c_adapter *adap = to_i2c_adapter(dev); | |
653 | struct i2c_board_info info; | |
654 | struct i2c_client *client; | |
655 | char *blank, end; | |
656 | int res; | |
657 | ||
99cd8e25 JD |
658 | memset(&info, 0, sizeof(struct i2c_board_info)); |
659 | ||
660 | blank = strchr(buf, ' '); | |
661 | if (!blank) { | |
662 | dev_err(dev, "%s: Missing parameters\n", "new_device"); | |
663 | return -EINVAL; | |
664 | } | |
665 | if (blank - buf > I2C_NAME_SIZE - 1) { | |
666 | dev_err(dev, "%s: Invalid device name\n", "new_device"); | |
667 | return -EINVAL; | |
668 | } | |
669 | memcpy(info.type, buf, blank - buf); | |
670 | ||
671 | /* Parse remaining parameters, reject extra parameters */ | |
672 | res = sscanf(++blank, "%hi%c", &info.addr, &end); | |
673 | if (res < 1) { | |
674 | dev_err(dev, "%s: Can't parse I2C address\n", "new_device"); | |
675 | return -EINVAL; | |
676 | } | |
677 | if (res > 1 && end != '\n') { | |
678 | dev_err(dev, "%s: Extra parameters\n", "new_device"); | |
679 | return -EINVAL; | |
680 | } | |
681 | ||
99cd8e25 JD |
682 | client = i2c_new_device(adap, &info); |
683 | if (!client) | |
3a89db5f | 684 | return -EINVAL; |
99cd8e25 JD |
685 | |
686 | /* Keep track of the added device */ | |
dafc50d1 | 687 | mutex_lock(&adap->userspace_clients_lock); |
6629dcff | 688 | list_add_tail(&client->detected, &adap->userspace_clients); |
dafc50d1 | 689 | mutex_unlock(&adap->userspace_clients_lock); |
99cd8e25 JD |
690 | dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device", |
691 | info.type, info.addr); | |
692 | ||
693 | return count; | |
694 | } | |
695 | ||
696 | /* | |
697 | * And of course let the users delete the devices they instantiated, if | |
698 | * they got it wrong. This interface can only be used to delete devices | |
699 | * instantiated by i2c_sysfs_new_device above. This guarantees that we | |
700 | * don't delete devices to which some kernel code still has references. | |
701 | * | |
702 | * Parameter checking may look overzealous, but we really don't want | |
703 | * the user to delete the wrong device. | |
704 | */ | |
705 | static ssize_t | |
706 | i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr, | |
707 | const char *buf, size_t count) | |
708 | { | |
709 | struct i2c_adapter *adap = to_i2c_adapter(dev); | |
710 | struct i2c_client *client, *next; | |
711 | unsigned short addr; | |
712 | char end; | |
713 | int res; | |
714 | ||
715 | /* Parse parameters, reject extra parameters */ | |
716 | res = sscanf(buf, "%hi%c", &addr, &end); | |
717 | if (res < 1) { | |
718 | dev_err(dev, "%s: Can't parse I2C address\n", "delete_device"); | |
719 | return -EINVAL; | |
720 | } | |
721 | if (res > 1 && end != '\n') { | |
722 | dev_err(dev, "%s: Extra parameters\n", "delete_device"); | |
723 | return -EINVAL; | |
724 | } | |
725 | ||
726 | /* Make sure the device was added through sysfs */ | |
727 | res = -ENOENT; | |
dafc50d1 | 728 | mutex_lock(&adap->userspace_clients_lock); |
6629dcff JD |
729 | list_for_each_entry_safe(client, next, &adap->userspace_clients, |
730 | detected) { | |
731 | if (client->addr == addr) { | |
99cd8e25 JD |
732 | dev_info(dev, "%s: Deleting device %s at 0x%02hx\n", |
733 | "delete_device", client->name, client->addr); | |
734 | ||
735 | list_del(&client->detected); | |
736 | i2c_unregister_device(client); | |
737 | res = count; | |
738 | break; | |
739 | } | |
740 | } | |
dafc50d1 | 741 | mutex_unlock(&adap->userspace_clients_lock); |
99cd8e25 JD |
742 | |
743 | if (res < 0) | |
744 | dev_err(dev, "%s: Can't find device in list\n", | |
745 | "delete_device"); | |
746 | return res; | |
747 | } | |
748 | ||
4f8cf824 JD |
749 | static DEVICE_ATTR(new_device, S_IWUSR, NULL, i2c_sysfs_new_device); |
750 | static DEVICE_ATTR(delete_device, S_IWUSR, NULL, i2c_sysfs_delete_device); | |
751 | ||
752 | static struct attribute *i2c_adapter_attrs[] = { | |
753 | &dev_attr_name.attr, | |
754 | &dev_attr_new_device.attr, | |
755 | &dev_attr_delete_device.attr, | |
756 | NULL | |
757 | }; | |
758 | ||
759 | static struct attribute_group i2c_adapter_attr_group = { | |
760 | .attrs = i2c_adapter_attrs, | |
761 | }; | |
762 | ||
763 | static const struct attribute_group *i2c_adapter_attr_groups[] = { | |
764 | &i2c_adapter_attr_group, | |
765 | NULL | |
16ffadfc | 766 | }; |
b119dc3f | 767 | |
0826374b | 768 | struct device_type i2c_adapter_type = { |
4f8cf824 JD |
769 | .groups = i2c_adapter_attr_groups, |
770 | .release = i2c_adapter_dev_release, | |
1da177e4 | 771 | }; |
0826374b | 772 | EXPORT_SYMBOL_GPL(i2c_adapter_type); |
1da177e4 | 773 | |
2bb5095a JD |
774 | #ifdef CONFIG_I2C_COMPAT |
775 | static struct class_compat *i2c_adapter_compat_class; | |
776 | #endif | |
777 | ||
9c1600ed DB |
778 | static void i2c_scan_static_board_info(struct i2c_adapter *adapter) |
779 | { | |
780 | struct i2c_devinfo *devinfo; | |
781 | ||
f18c41da | 782 | down_read(&__i2c_board_lock); |
9c1600ed DB |
783 | list_for_each_entry(devinfo, &__i2c_board_list, list) { |
784 | if (devinfo->busnum == adapter->nr | |
785 | && !i2c_new_device(adapter, | |
786 | &devinfo->board_info)) | |
09b8ce0a ZX |
787 | dev_err(&adapter->dev, |
788 | "Can't create device at 0x%02x\n", | |
9c1600ed DB |
789 | devinfo->board_info.addr); |
790 | } | |
f18c41da | 791 | up_read(&__i2c_board_lock); |
9c1600ed DB |
792 | } |
793 | ||
69b0089a JD |
794 | static int i2c_do_add_adapter(struct i2c_driver *driver, |
795 | struct i2c_adapter *adap) | |
026526f5 | 796 | { |
4735c98f JD |
797 | /* Detect supported devices on that bus, and instantiate them */ |
798 | i2c_detect(adap, driver); | |
799 | ||
800 | /* Let legacy drivers scan this bus for matching devices */ | |
026526f5 | 801 | if (driver->attach_adapter) { |
a920ff41 JD |
802 | dev_warn(&adap->dev, "%s: attach_adapter method is deprecated\n", |
803 | driver->driver.name); | |
fe6fc258 JD |
804 | dev_warn(&adap->dev, "Please use another way to instantiate " |
805 | "your i2c_client\n"); | |
026526f5 JD |
806 | /* We ignore the return code; if it fails, too bad */ |
807 | driver->attach_adapter(adap); | |
808 | } | |
809 | return 0; | |
810 | } | |
811 | ||
69b0089a JD |
812 | static int __process_new_adapter(struct device_driver *d, void *data) |
813 | { | |
814 | return i2c_do_add_adapter(to_i2c_driver(d), data); | |
815 | } | |
816 | ||
6e13e641 | 817 | static int i2c_register_adapter(struct i2c_adapter *adap) |
1da177e4 | 818 | { |
d6703281 | 819 | int res = 0; |
1da177e4 | 820 | |
1d0b19c9 | 821 | /* Can't register until after driver model init */ |
35fc37f8 JD |
822 | if (unlikely(WARN_ON(!i2c_bus_type.p))) { |
823 | res = -EAGAIN; | |
824 | goto out_list; | |
825 | } | |
1d0b19c9 | 826 | |
2236baa7 JD |
827 | /* Sanity checks */ |
828 | if (unlikely(adap->name[0] == '\0')) { | |
829 | pr_err("i2c-core: Attempt to register an adapter with " | |
830 | "no name!\n"); | |
831 | return -EINVAL; | |
832 | } | |
833 | if (unlikely(!adap->algo)) { | |
834 | pr_err("i2c-core: Attempt to register adapter '%s' with " | |
835 | "no algo!\n", adap->name); | |
836 | return -EINVAL; | |
837 | } | |
838 | ||
194684e5 | 839 | rt_mutex_init(&adap->bus_lock); |
dafc50d1 | 840 | mutex_init(&adap->userspace_clients_lock); |
6629dcff | 841 | INIT_LIST_HEAD(&adap->userspace_clients); |
1da177e4 | 842 | |
8fcfef6e JD |
843 | /* Set default timeout to 1 second if not already set */ |
844 | if (adap->timeout == 0) | |
845 | adap->timeout = HZ; | |
846 | ||
27d9c183 | 847 | dev_set_name(&adap->dev, "i2c-%d", adap->nr); |
4f8cf824 JD |
848 | adap->dev.bus = &i2c_bus_type; |
849 | adap->dev.type = &i2c_adapter_type; | |
b119c6c9 JD |
850 | res = device_register(&adap->dev); |
851 | if (res) | |
852 | goto out_list; | |
1da177e4 | 853 | |
b6d7b3d1 JD |
854 | dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name); |
855 | ||
2bb5095a JD |
856 | #ifdef CONFIG_I2C_COMPAT |
857 | res = class_compat_create_link(i2c_adapter_compat_class, &adap->dev, | |
858 | adap->dev.parent); | |
859 | if (res) | |
860 | dev_warn(&adap->dev, | |
861 | "Failed to create compatibility class link\n"); | |
862 | #endif | |
863 | ||
729d6dd5 | 864 | /* create pre-declared device nodes */ |
6e13e641 DB |
865 | if (adap->nr < __i2c_first_dynamic_bus_num) |
866 | i2c_scan_static_board_info(adap); | |
867 | ||
4735c98f | 868 | /* Notify drivers */ |
35fc37f8 | 869 | mutex_lock(&core_lock); |
d6703281 | 870 | bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter); |
caada32a | 871 | mutex_unlock(&core_lock); |
35fc37f8 JD |
872 | |
873 | return 0; | |
b119c6c9 | 874 | |
b119c6c9 | 875 | out_list: |
35fc37f8 | 876 | mutex_lock(&core_lock); |
b119c6c9 | 877 | idr_remove(&i2c_adapter_idr, adap->nr); |
35fc37f8 JD |
878 | mutex_unlock(&core_lock); |
879 | return res; | |
1da177e4 LT |
880 | } |
881 | ||
6e13e641 DB |
882 | /** |
883 | * i2c_add_adapter - declare i2c adapter, use dynamic bus number | |
884 | * @adapter: the adapter to add | |
d64f73be | 885 | * Context: can sleep |
6e13e641 DB |
886 | * |
887 | * This routine is used to declare an I2C adapter when its bus number | |
888 | * doesn't matter. Examples: for I2C adapters dynamically added by | |
889 | * USB links or PCI plugin cards. | |
890 | * | |
891 | * When this returns zero, a new bus number was allocated and stored | |
892 | * in adap->nr, and the specified adapter became available for clients. | |
893 | * Otherwise, a negative errno value is returned. | |
894 | */ | |
895 | int i2c_add_adapter(struct i2c_adapter *adapter) | |
896 | { | |
897 | int id, res = 0; | |
898 | ||
899 | retry: | |
900 | if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) | |
901 | return -ENOMEM; | |
902 | ||
caada32a | 903 | mutex_lock(&core_lock); |
6e13e641 DB |
904 | /* "above" here means "above or equal to", sigh */ |
905 | res = idr_get_new_above(&i2c_adapter_idr, adapter, | |
906 | __i2c_first_dynamic_bus_num, &id); | |
caada32a | 907 | mutex_unlock(&core_lock); |
6e13e641 DB |
908 | |
909 | if (res < 0) { | |
910 | if (res == -EAGAIN) | |
911 | goto retry; | |
912 | return res; | |
913 | } | |
914 | ||
915 | adapter->nr = id; | |
916 | return i2c_register_adapter(adapter); | |
917 | } | |
918 | EXPORT_SYMBOL(i2c_add_adapter); | |
919 | ||
920 | /** | |
921 | * i2c_add_numbered_adapter - declare i2c adapter, use static bus number | |
922 | * @adap: the adapter to register (with adap->nr initialized) | |
d64f73be | 923 | * Context: can sleep |
6e13e641 DB |
924 | * |
925 | * This routine is used to declare an I2C adapter when its bus number | |
8c07e46f RD |
926 | * matters. For example, use it for I2C adapters from system-on-chip CPUs, |
927 | * or otherwise built in to the system's mainboard, and where i2c_board_info | |
6e13e641 DB |
928 | * is used to properly configure I2C devices. |
929 | * | |
488bf314 GL |
930 | * If the requested bus number is set to -1, then this function will behave |
931 | * identically to i2c_add_adapter, and will dynamically assign a bus number. | |
932 | * | |
6e13e641 DB |
933 | * If no devices have pre-been declared for this bus, then be sure to |
934 | * register the adapter before any dynamically allocated ones. Otherwise | |
935 | * the required bus ID may not be available. | |
936 | * | |
937 | * When this returns zero, the specified adapter became available for | |
938 | * clients using the bus number provided in adap->nr. Also, the table | |
939 | * of I2C devices pre-declared using i2c_register_board_info() is scanned, | |
940 | * and the appropriate driver model device nodes are created. Otherwise, a | |
941 | * negative errno value is returned. | |
942 | */ | |
943 | int i2c_add_numbered_adapter(struct i2c_adapter *adap) | |
944 | { | |
945 | int id; | |
946 | int status; | |
947 | ||
488bf314 GL |
948 | if (adap->nr == -1) /* -1 means dynamically assign bus id */ |
949 | return i2c_add_adapter(adap); | |
6e13e641 DB |
950 | if (adap->nr & ~MAX_ID_MASK) |
951 | return -EINVAL; | |
952 | ||
953 | retry: | |
954 | if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) | |
955 | return -ENOMEM; | |
956 | ||
caada32a | 957 | mutex_lock(&core_lock); |
6e13e641 DB |
958 | /* "above" here means "above or equal to", sigh; |
959 | * we need the "equal to" result to force the result | |
960 | */ | |
961 | status = idr_get_new_above(&i2c_adapter_idr, adap, adap->nr, &id); | |
962 | if (status == 0 && id != adap->nr) { | |
963 | status = -EBUSY; | |
964 | idr_remove(&i2c_adapter_idr, id); | |
965 | } | |
caada32a | 966 | mutex_unlock(&core_lock); |
6e13e641 DB |
967 | if (status == -EAGAIN) |
968 | goto retry; | |
969 | ||
970 | if (status == 0) | |
971 | status = i2c_register_adapter(adap); | |
972 | return status; | |
973 | } | |
974 | EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter); | |
975 | ||
69b0089a JD |
976 | static int i2c_do_del_adapter(struct i2c_driver *driver, |
977 | struct i2c_adapter *adapter) | |
026526f5 | 978 | { |
4735c98f | 979 | struct i2c_client *client, *_n; |
026526f5 JD |
980 | int res; |
981 | ||
acec211c JD |
982 | /* Remove the devices we created ourselves as the result of hardware |
983 | * probing (using a driver's detect method) */ | |
4735c98f JD |
984 | list_for_each_entry_safe(client, _n, &driver->clients, detected) { |
985 | if (client->adapter == adapter) { | |
986 | dev_dbg(&adapter->dev, "Removing %s at 0x%x\n", | |
987 | client->name, client->addr); | |
988 | list_del(&client->detected); | |
989 | i2c_unregister_device(client); | |
990 | } | |
991 | } | |
992 | ||
026526f5 JD |
993 | if (!driver->detach_adapter) |
994 | return 0; | |
a920ff41 JD |
995 | dev_warn(&adapter->dev, "%s: detach_adapter method is deprecated\n", |
996 | driver->driver.name); | |
026526f5 JD |
997 | res = driver->detach_adapter(adapter); |
998 | if (res) | |
999 | dev_err(&adapter->dev, "detach_adapter failed (%d) " | |
1000 | "for driver [%s]\n", res, driver->driver.name); | |
1001 | return res; | |
1002 | } | |
1003 | ||
e549c2b5 | 1004 | static int __unregister_client(struct device *dev, void *dummy) |
5219bf88 JD |
1005 | { |
1006 | struct i2c_client *client = i2c_verify_client(dev); | |
1007 | if (client && strcmp(client->name, "dummy")) | |
1008 | i2c_unregister_device(client); | |
1009 | return 0; | |
1010 | } | |
1011 | ||
1012 | static int __unregister_dummy(struct device *dev, void *dummy) | |
e549c2b5 JD |
1013 | { |
1014 | struct i2c_client *client = i2c_verify_client(dev); | |
1015 | if (client) | |
1016 | i2c_unregister_device(client); | |
1017 | return 0; | |
1018 | } | |
1019 | ||
69b0089a JD |
1020 | static int __process_removed_adapter(struct device_driver *d, void *data) |
1021 | { | |
1022 | return i2c_do_del_adapter(to_i2c_driver(d), data); | |
1023 | } | |
1024 | ||
d64f73be DB |
1025 | /** |
1026 | * i2c_del_adapter - unregister I2C adapter | |
1027 | * @adap: the adapter being unregistered | |
1028 | * Context: can sleep | |
1029 | * | |
1030 | * This unregisters an I2C adapter which was previously registered | |
1031 | * by @i2c_add_adapter or @i2c_add_numbered_adapter. | |
1032 | */ | |
1da177e4 LT |
1033 | int i2c_del_adapter(struct i2c_adapter *adap) |
1034 | { | |
1da177e4 | 1035 | int res = 0; |
35fc37f8 | 1036 | struct i2c_adapter *found; |
bbd2d9c9 | 1037 | struct i2c_client *client, *next; |
1da177e4 LT |
1038 | |
1039 | /* First make sure that this adapter was ever added */ | |
35fc37f8 JD |
1040 | mutex_lock(&core_lock); |
1041 | found = idr_find(&i2c_adapter_idr, adap->nr); | |
1042 | mutex_unlock(&core_lock); | |
1043 | if (found != adap) { | |
b6d7b3d1 JD |
1044 | pr_debug("i2c-core: attempting to delete unregistered " |
1045 | "adapter [%s]\n", adap->name); | |
35fc37f8 | 1046 | return -EINVAL; |
1da177e4 LT |
1047 | } |
1048 | ||
026526f5 | 1049 | /* Tell drivers about this removal */ |
35fc37f8 | 1050 | mutex_lock(&core_lock); |
026526f5 | 1051 | res = bus_for_each_drv(&i2c_bus_type, NULL, adap, |
69b0089a | 1052 | __process_removed_adapter); |
35fc37f8 | 1053 | mutex_unlock(&core_lock); |
026526f5 | 1054 | if (res) |
35fc37f8 | 1055 | return res; |
1da177e4 | 1056 | |
bbd2d9c9 | 1057 | /* Remove devices instantiated from sysfs */ |
dafc50d1 | 1058 | mutex_lock(&adap->userspace_clients_lock); |
6629dcff JD |
1059 | list_for_each_entry_safe(client, next, &adap->userspace_clients, |
1060 | detected) { | |
1061 | dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name, | |
1062 | client->addr); | |
1063 | list_del(&client->detected); | |
1064 | i2c_unregister_device(client); | |
bbd2d9c9 | 1065 | } |
dafc50d1 | 1066 | mutex_unlock(&adap->userspace_clients_lock); |
bbd2d9c9 | 1067 | |
e549c2b5 | 1068 | /* Detach any active clients. This can't fail, thus we do not |
5219bf88 JD |
1069 | * check the returned value. This is a two-pass process, because |
1070 | * we can't remove the dummy devices during the first pass: they | |
1071 | * could have been instantiated by real devices wishing to clean | |
1072 | * them up properly, so we give them a chance to do that first. */ | |
e549c2b5 | 1073 | res = device_for_each_child(&adap->dev, NULL, __unregister_client); |
5219bf88 | 1074 | res = device_for_each_child(&adap->dev, NULL, __unregister_dummy); |
1da177e4 | 1075 | |
2bb5095a JD |
1076 | #ifdef CONFIG_I2C_COMPAT |
1077 | class_compat_remove_link(i2c_adapter_compat_class, &adap->dev, | |
1078 | adap->dev.parent); | |
1079 | #endif | |
1080 | ||
c5567521 TLSC |
1081 | /* device name is gone after device_unregister */ |
1082 | dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name); | |
1083 | ||
1da177e4 LT |
1084 | /* clean up the sysfs representation */ |
1085 | init_completion(&adap->dev_released); | |
1da177e4 | 1086 | device_unregister(&adap->dev); |
1da177e4 LT |
1087 | |
1088 | /* wait for sysfs to drop all references */ | |
1089 | wait_for_completion(&adap->dev_released); | |
1da177e4 | 1090 | |
6e13e641 | 1091 | /* free bus id */ |
35fc37f8 | 1092 | mutex_lock(&core_lock); |
1da177e4 | 1093 | idr_remove(&i2c_adapter_idr, adap->nr); |
35fc37f8 | 1094 | mutex_unlock(&core_lock); |
1da177e4 | 1095 | |
bd4bc3db JD |
1096 | /* Clear the device structure in case this adapter is ever going to be |
1097 | added again */ | |
1098 | memset(&adap->dev, 0, sizeof(adap->dev)); | |
1099 | ||
35fc37f8 | 1100 | return 0; |
1da177e4 | 1101 | } |
c0564606 | 1102 | EXPORT_SYMBOL(i2c_del_adapter); |
1da177e4 LT |
1103 | |
1104 | ||
7b4fbc50 DB |
1105 | /* ------------------------------------------------------------------------- */ |
1106 | ||
7ae31482 JD |
1107 | int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *)) |
1108 | { | |
1109 | int res; | |
1110 | ||
1111 | mutex_lock(&core_lock); | |
1112 | res = bus_for_each_dev(&i2c_bus_type, NULL, data, fn); | |
1113 | mutex_unlock(&core_lock); | |
1114 | ||
1115 | return res; | |
1116 | } | |
1117 | EXPORT_SYMBOL_GPL(i2c_for_each_dev); | |
1118 | ||
69b0089a | 1119 | static int __process_new_driver(struct device *dev, void *data) |
7f101a97 | 1120 | { |
4f8cf824 JD |
1121 | if (dev->type != &i2c_adapter_type) |
1122 | return 0; | |
69b0089a | 1123 | return i2c_do_add_adapter(data, to_i2c_adapter(dev)); |
7f101a97 DY |
1124 | } |
1125 | ||
7b4fbc50 DB |
1126 | /* |
1127 | * An i2c_driver is used with one or more i2c_client (device) nodes to access | |
729d6dd5 | 1128 | * i2c slave chips, on a bus instance associated with some i2c_adapter. |
1da177e4 LT |
1129 | */ |
1130 | ||
de59cf9e | 1131 | int i2c_register_driver(struct module *owner, struct i2c_driver *driver) |
1da177e4 | 1132 | { |
7eebcb7c | 1133 | int res; |
1da177e4 | 1134 | |
1d0b19c9 DB |
1135 | /* Can't register until after driver model init */ |
1136 | if (unlikely(WARN_ON(!i2c_bus_type.p))) | |
1137 | return -EAGAIN; | |
1138 | ||
1da177e4 | 1139 | /* add the driver to the list of i2c drivers in the driver core */ |
de59cf9e | 1140 | driver->driver.owner = owner; |
1da177e4 | 1141 | driver->driver.bus = &i2c_bus_type; |
1da177e4 | 1142 | |
729d6dd5 | 1143 | /* When registration returns, the driver core |
6e13e641 DB |
1144 | * will have called probe() for all matching-but-unbound devices. |
1145 | */ | |
1da177e4 LT |
1146 | res = driver_register(&driver->driver); |
1147 | if (res) | |
7eebcb7c | 1148 | return res; |
438d6c2c | 1149 | |
f4e8db31 MB |
1150 | /* Drivers should switch to dev_pm_ops instead. */ |
1151 | if (driver->suspend) | |
1152 | pr_warn("i2c-core: driver [%s] using legacy suspend method\n", | |
1153 | driver->driver.name); | |
1154 | if (driver->resume) | |
1155 | pr_warn("i2c-core: driver [%s] using legacy resume method\n", | |
1156 | driver->driver.name); | |
1157 | ||
35d8b2e6 | 1158 | pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name); |
1da177e4 | 1159 | |
4735c98f JD |
1160 | INIT_LIST_HEAD(&driver->clients); |
1161 | /* Walk the adapters that are already present */ | |
7ae31482 | 1162 | i2c_for_each_dev(driver, __process_new_driver); |
35fc37f8 | 1163 | |
7f101a97 DY |
1164 | return 0; |
1165 | } | |
1166 | EXPORT_SYMBOL(i2c_register_driver); | |
1167 | ||
69b0089a | 1168 | static int __process_removed_driver(struct device *dev, void *data) |
7f101a97 | 1169 | { |
4f8cf824 JD |
1170 | if (dev->type != &i2c_adapter_type) |
1171 | return 0; | |
69b0089a | 1172 | return i2c_do_del_adapter(data, to_i2c_adapter(dev)); |
1da177e4 LT |
1173 | } |
1174 | ||
a1d9e6e4 DB |
1175 | /** |
1176 | * i2c_del_driver - unregister I2C driver | |
1177 | * @driver: the driver being unregistered | |
d64f73be | 1178 | * Context: can sleep |
a1d9e6e4 | 1179 | */ |
b3e82096 | 1180 | void i2c_del_driver(struct i2c_driver *driver) |
1da177e4 | 1181 | { |
7ae31482 | 1182 | i2c_for_each_dev(driver, __process_removed_driver); |
1da177e4 LT |
1183 | |
1184 | driver_unregister(&driver->driver); | |
35d8b2e6 | 1185 | pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name); |
1da177e4 | 1186 | } |
c0564606 | 1187 | EXPORT_SYMBOL(i2c_del_driver); |
1da177e4 | 1188 | |
7b4fbc50 DB |
1189 | /* ------------------------------------------------------------------------- */ |
1190 | ||
e48d3319 JD |
1191 | /** |
1192 | * i2c_use_client - increments the reference count of the i2c client structure | |
1193 | * @client: the client being referenced | |
1194 | * | |
1195 | * Each live reference to a client should be refcounted. The driver model does | |
1196 | * that automatically as part of driver binding, so that most drivers don't | |
1197 | * need to do this explicitly: they hold a reference until they're unbound | |
1198 | * from the device. | |
1199 | * | |
1200 | * A pointer to the client with the incremented reference counter is returned. | |
1201 | */ | |
1202 | struct i2c_client *i2c_use_client(struct i2c_client *client) | |
1da177e4 | 1203 | { |
6ea438ec DB |
1204 | if (client && get_device(&client->dev)) |
1205 | return client; | |
1206 | return NULL; | |
1da177e4 | 1207 | } |
c0564606 | 1208 | EXPORT_SYMBOL(i2c_use_client); |
1da177e4 | 1209 | |
e48d3319 JD |
1210 | /** |
1211 | * i2c_release_client - release a use of the i2c client structure | |
1212 | * @client: the client being no longer referenced | |
1213 | * | |
1214 | * Must be called when a user of a client is finished with it. | |
1215 | */ | |
1216 | void i2c_release_client(struct i2c_client *client) | |
1da177e4 | 1217 | { |
6ea438ec DB |
1218 | if (client) |
1219 | put_device(&client->dev); | |
1da177e4 | 1220 | } |
c0564606 | 1221 | EXPORT_SYMBOL(i2c_release_client); |
1da177e4 | 1222 | |
9b766b81 DB |
1223 | struct i2c_cmd_arg { |
1224 | unsigned cmd; | |
1225 | void *arg; | |
1226 | }; | |
1227 | ||
1228 | static int i2c_cmd(struct device *dev, void *_arg) | |
1229 | { | |
1230 | struct i2c_client *client = i2c_verify_client(dev); | |
1231 | struct i2c_cmd_arg *arg = _arg; | |
1232 | ||
1233 | if (client && client->driver && client->driver->command) | |
1234 | client->driver->command(client, arg->cmd, arg->arg); | |
1235 | return 0; | |
1236 | } | |
1237 | ||
1da177e4 LT |
1238 | void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg) |
1239 | { | |
9b766b81 | 1240 | struct i2c_cmd_arg cmd_arg; |
1da177e4 | 1241 | |
9b766b81 DB |
1242 | cmd_arg.cmd = cmd; |
1243 | cmd_arg.arg = arg; | |
1244 | device_for_each_child(&adap->dev, &cmd_arg, i2c_cmd); | |
1da177e4 | 1245 | } |
c0564606 | 1246 | EXPORT_SYMBOL(i2c_clients_command); |
1da177e4 LT |
1247 | |
1248 | static int __init i2c_init(void) | |
1249 | { | |
1250 | int retval; | |
1251 | ||
1252 | retval = bus_register(&i2c_bus_type); | |
1da177e4 LT |
1253 | if (retval) |
1254 | return retval; | |
2bb5095a JD |
1255 | #ifdef CONFIG_I2C_COMPAT |
1256 | i2c_adapter_compat_class = class_compat_register("i2c-adapter"); | |
1257 | if (!i2c_adapter_compat_class) { | |
1258 | retval = -ENOMEM; | |
1259 | goto bus_err; | |
1260 | } | |
1261 | #endif | |
e9f1373b DB |
1262 | retval = i2c_add_driver(&dummy_driver); |
1263 | if (retval) | |
2bb5095a | 1264 | goto class_err; |
e9f1373b DB |
1265 | return 0; |
1266 | ||
2bb5095a JD |
1267 | class_err: |
1268 | #ifdef CONFIG_I2C_COMPAT | |
1269 | class_compat_unregister(i2c_adapter_compat_class); | |
e9f1373b | 1270 | bus_err: |
2bb5095a | 1271 | #endif |
e9f1373b DB |
1272 | bus_unregister(&i2c_bus_type); |
1273 | return retval; | |
1da177e4 LT |
1274 | } |
1275 | ||
1276 | static void __exit i2c_exit(void) | |
1277 | { | |
e9f1373b | 1278 | i2c_del_driver(&dummy_driver); |
2bb5095a JD |
1279 | #ifdef CONFIG_I2C_COMPAT |
1280 | class_compat_unregister(i2c_adapter_compat_class); | |
1281 | #endif | |
1da177e4 LT |
1282 | bus_unregister(&i2c_bus_type); |
1283 | } | |
1284 | ||
a10f9e7c DB |
1285 | /* We must initialize early, because some subsystems register i2c drivers |
1286 | * in subsys_initcall() code, but are linked (and initialized) before i2c. | |
1287 | */ | |
1288 | postcore_initcall(i2c_init); | |
1da177e4 LT |
1289 | module_exit(i2c_exit); |
1290 | ||
1291 | /* ---------------------------------------------------- | |
1292 | * the functional interface to the i2c busses. | |
1293 | * ---------------------------------------------------- | |
1294 | */ | |
1295 | ||
a1cdedac DB |
1296 | /** |
1297 | * i2c_transfer - execute a single or combined I2C message | |
1298 | * @adap: Handle to I2C bus | |
1299 | * @msgs: One or more messages to execute before STOP is issued to | |
1300 | * terminate the operation; each message begins with a START. | |
1301 | * @num: Number of messages to be executed. | |
1302 | * | |
1303 | * Returns negative errno, else the number of messages executed. | |
1304 | * | |
1305 | * Note that there is no requirement that each message be sent to | |
1306 | * the same slave address, although that is the most common model. | |
1307 | */ | |
09b8ce0a | 1308 | int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) |
1da177e4 | 1309 | { |
66b650f0 CW |
1310 | unsigned long orig_jiffies; |
1311 | int ret, try; | |
1da177e4 | 1312 | |
a1cdedac DB |
1313 | /* REVISIT the fault reporting model here is weak: |
1314 | * | |
1315 | * - When we get an error after receiving N bytes from a slave, | |
1316 | * there is no way to report "N". | |
1317 | * | |
1318 | * - When we get a NAK after transmitting N bytes to a slave, | |
1319 | * there is no way to report "N" ... or to let the master | |
1320 | * continue executing the rest of this combined message, if | |
1321 | * that's the appropriate response. | |
1322 | * | |
1323 | * - When for example "num" is two and we successfully complete | |
1324 | * the first message but get an error part way through the | |
1325 | * second, it's unclear whether that should be reported as | |
1326 | * one (discarding status on the second message) or errno | |
1327 | * (discarding status on the first one). | |
1328 | */ | |
1329 | ||
1da177e4 LT |
1330 | if (adap->algo->master_xfer) { |
1331 | #ifdef DEBUG | |
1332 | for (ret = 0; ret < num; ret++) { | |
1333 | dev_dbg(&adap->dev, "master_xfer[%d] %c, addr=0x%02x, " | |
209d27c3 JD |
1334 | "len=%d%s\n", ret, (msgs[ret].flags & I2C_M_RD) |
1335 | ? 'R' : 'W', msgs[ret].addr, msgs[ret].len, | |
1336 | (msgs[ret].flags & I2C_M_RECV_LEN) ? "+" : ""); | |
1da177e4 LT |
1337 | } |
1338 | #endif | |
1339 | ||
cea443a8 | 1340 | if (in_atomic() || irqs_disabled()) { |
fe61e07e | 1341 | ret = i2c_trylock_adapter(adap); |
cea443a8 MR |
1342 | if (!ret) |
1343 | /* I2C activity is ongoing. */ | |
1344 | return -EAGAIN; | |
1345 | } else { | |
fe61e07e | 1346 | i2c_lock_adapter(adap); |
cea443a8 MR |
1347 | } |
1348 | ||
66b650f0 CW |
1349 | /* Retry automatically on arbitration loss */ |
1350 | orig_jiffies = jiffies; | |
1351 | for (ret = 0, try = 0; try <= adap->retries; try++) { | |
1352 | ret = adap->algo->master_xfer(adap, msgs, num); | |
1353 | if (ret != -EAGAIN) | |
1354 | break; | |
1355 | if (time_after(jiffies, orig_jiffies + adap->timeout)) | |
1356 | break; | |
1357 | } | |
fe61e07e | 1358 | i2c_unlock_adapter(adap); |
1da177e4 LT |
1359 | |
1360 | return ret; | |
1361 | } else { | |
1362 | dev_dbg(&adap->dev, "I2C level transfers not supported\n"); | |
24a5bb7b | 1363 | return -EOPNOTSUPP; |
1da177e4 LT |
1364 | } |
1365 | } | |
c0564606 | 1366 | EXPORT_SYMBOL(i2c_transfer); |
1da177e4 | 1367 | |
a1cdedac DB |
1368 | /** |
1369 | * i2c_master_send - issue a single I2C message in master transmit mode | |
1370 | * @client: Handle to slave device | |
1371 | * @buf: Data that will be written to the slave | |
0c43ea54 | 1372 | * @count: How many bytes to write, must be less than 64k since msg.len is u16 |
a1cdedac DB |
1373 | * |
1374 | * Returns negative errno, or else the number of bytes written. | |
1375 | */ | |
0cc43a18 | 1376 | int i2c_master_send(const struct i2c_client *client, const char *buf, int count) |
1da177e4 LT |
1377 | { |
1378 | int ret; | |
7225acf4 | 1379 | struct i2c_adapter *adap = client->adapter; |
1da177e4 LT |
1380 | struct i2c_msg msg; |
1381 | ||
815f55f2 JD |
1382 | msg.addr = client->addr; |
1383 | msg.flags = client->flags & I2C_M_TEN; | |
1384 | msg.len = count; | |
1385 | msg.buf = (char *)buf; | |
438d6c2c | 1386 | |
815f55f2 | 1387 | ret = i2c_transfer(adap, &msg, 1); |
1da177e4 | 1388 | |
834aa6f3 WS |
1389 | /* |
1390 | * If everything went ok (i.e. 1 msg transmitted), return #bytes | |
1391 | * transmitted, else error code. | |
1392 | */ | |
815f55f2 | 1393 | return (ret == 1) ? count : ret; |
1da177e4 | 1394 | } |
c0564606 | 1395 | EXPORT_SYMBOL(i2c_master_send); |
1da177e4 | 1396 | |
a1cdedac DB |
1397 | /** |
1398 | * i2c_master_recv - issue a single I2C message in master receive mode | |
1399 | * @client: Handle to slave device | |
1400 | * @buf: Where to store data read from slave | |
0c43ea54 | 1401 | * @count: How many bytes to read, must be less than 64k since msg.len is u16 |
a1cdedac DB |
1402 | * |
1403 | * Returns negative errno, or else the number of bytes read. | |
1404 | */ | |
0cc43a18 | 1405 | int i2c_master_recv(const struct i2c_client *client, char *buf, int count) |
1da177e4 | 1406 | { |
7225acf4 | 1407 | struct i2c_adapter *adap = client->adapter; |
1da177e4 LT |
1408 | struct i2c_msg msg; |
1409 | int ret; | |
815f55f2 JD |
1410 | |
1411 | msg.addr = client->addr; | |
1412 | msg.flags = client->flags & I2C_M_TEN; | |
1413 | msg.flags |= I2C_M_RD; | |
1414 | msg.len = count; | |
1415 | msg.buf = buf; | |
1416 | ||
1417 | ret = i2c_transfer(adap, &msg, 1); | |
1418 | ||
834aa6f3 WS |
1419 | /* |
1420 | * If everything went ok (i.e. 1 msg received), return #bytes received, | |
1421 | * else error code. | |
1422 | */ | |
815f55f2 | 1423 | return (ret == 1) ? count : ret; |
1da177e4 | 1424 | } |
c0564606 | 1425 | EXPORT_SYMBOL(i2c_master_recv); |
1da177e4 | 1426 | |
1da177e4 LT |
1427 | /* ---------------------------------------------------- |
1428 | * the i2c address scanning function | |
1429 | * Will not work for 10-bit addresses! | |
1430 | * ---------------------------------------------------- | |
1431 | */ | |
1da177e4 | 1432 | |
63e4e802 JD |
1433 | /* |
1434 | * Legacy default probe function, mostly relevant for SMBus. The default | |
1435 | * probe method is a quick write, but it is known to corrupt the 24RF08 | |
1436 | * EEPROMs due to a state machine bug, and could also irreversibly | |
1437 | * write-protect some EEPROMs, so for address ranges 0x30-0x37 and 0x50-0x5f, | |
1438 | * we use a short byte read instead. Also, some bus drivers don't implement | |
1439 | * quick write, so we fallback to a byte read in that case too. | |
1440 | * On x86, there is another special case for FSC hardware monitoring chips, | |
1441 | * which want regular byte reads (address 0x73.) Fortunately, these are the | |
1442 | * only known chips using this I2C address on PC hardware. | |
1443 | * Returns 1 if probe succeeded, 0 if not. | |
1444 | */ | |
1445 | static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr) | |
1446 | { | |
1447 | int err; | |
1448 | union i2c_smbus_data dummy; | |
1449 | ||
1450 | #ifdef CONFIG_X86 | |
1451 | if (addr == 0x73 && (adap->class & I2C_CLASS_HWMON) | |
1452 | && i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE_DATA)) | |
1453 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
1454 | I2C_SMBUS_BYTE_DATA, &dummy); | |
1455 | else | |
1456 | #endif | |
8031d79b JD |
1457 | if (!((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50) |
1458 | && i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) | |
63e4e802 JD |
1459 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0, |
1460 | I2C_SMBUS_QUICK, NULL); | |
8031d79b JD |
1461 | else if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) |
1462 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
1463 | I2C_SMBUS_BYTE, &dummy); | |
1464 | else { | |
1465 | dev_warn(&adap->dev, "No suitable probing method supported\n"); | |
1466 | err = -EOPNOTSUPP; | |
1467 | } | |
63e4e802 JD |
1468 | |
1469 | return err >= 0; | |
1470 | } | |
1471 | ||
ccfbbd08 | 1472 | static int i2c_detect_address(struct i2c_client *temp_client, |
4735c98f JD |
1473 | struct i2c_driver *driver) |
1474 | { | |
1475 | struct i2c_board_info info; | |
1476 | struct i2c_adapter *adapter = temp_client->adapter; | |
1477 | int addr = temp_client->addr; | |
1478 | int err; | |
1479 | ||
1480 | /* Make sure the address is valid */ | |
656b8761 JD |
1481 | err = i2c_check_addr_validity(addr); |
1482 | if (err) { | |
4735c98f JD |
1483 | dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n", |
1484 | addr); | |
656b8761 | 1485 | return err; |
4735c98f JD |
1486 | } |
1487 | ||
1488 | /* Skip if already in use */ | |
3b5f794b | 1489 | if (i2c_check_addr_busy(adapter, addr)) |
4735c98f JD |
1490 | return 0; |
1491 | ||
ccfbbd08 | 1492 | /* Make sure there is something at this address */ |
63e4e802 JD |
1493 | if (!i2c_default_probe(adapter, addr)) |
1494 | return 0; | |
4735c98f JD |
1495 | |
1496 | /* Finally call the custom detection function */ | |
1497 | memset(&info, 0, sizeof(struct i2c_board_info)); | |
1498 | info.addr = addr; | |
310ec792 | 1499 | err = driver->detect(temp_client, &info); |
4735c98f JD |
1500 | if (err) { |
1501 | /* -ENODEV is returned if the detection fails. We catch it | |
1502 | here as this isn't an error. */ | |
1503 | return err == -ENODEV ? 0 : err; | |
1504 | } | |
1505 | ||
1506 | /* Consistency check */ | |
1507 | if (info.type[0] == '\0') { | |
1508 | dev_err(&adapter->dev, "%s detection function provided " | |
1509 | "no name for 0x%x\n", driver->driver.name, | |
1510 | addr); | |
1511 | } else { | |
1512 | struct i2c_client *client; | |
1513 | ||
1514 | /* Detection succeeded, instantiate the device */ | |
1515 | dev_dbg(&adapter->dev, "Creating %s at 0x%02x\n", | |
1516 | info.type, info.addr); | |
1517 | client = i2c_new_device(adapter, &info); | |
1518 | if (client) | |
1519 | list_add_tail(&client->detected, &driver->clients); | |
1520 | else | |
1521 | dev_err(&adapter->dev, "Failed creating %s at 0x%02x\n", | |
1522 | info.type, info.addr); | |
1523 | } | |
1524 | return 0; | |
1525 | } | |
1526 | ||
1527 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver) | |
1528 | { | |
c3813d6a | 1529 | const unsigned short *address_list; |
4735c98f JD |
1530 | struct i2c_client *temp_client; |
1531 | int i, err = 0; | |
1532 | int adap_id = i2c_adapter_id(adapter); | |
1533 | ||
c3813d6a JD |
1534 | address_list = driver->address_list; |
1535 | if (!driver->detect || !address_list) | |
4735c98f JD |
1536 | return 0; |
1537 | ||
51b54ba9 JD |
1538 | /* Stop here if the classes do not match */ |
1539 | if (!(adapter->class & driver->class)) | |
1540 | return 0; | |
1541 | ||
4735c98f JD |
1542 | /* Set up a temporary client to help detect callback */ |
1543 | temp_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL); | |
1544 | if (!temp_client) | |
1545 | return -ENOMEM; | |
1546 | temp_client->adapter = adapter; | |
1547 | ||
c3813d6a | 1548 | for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) { |
4735c98f | 1549 | dev_dbg(&adapter->dev, "found normal entry for adapter %d, " |
c3813d6a JD |
1550 | "addr 0x%02x\n", adap_id, address_list[i]); |
1551 | temp_client->addr = address_list[i]; | |
ccfbbd08 | 1552 | err = i2c_detect_address(temp_client, driver); |
51b54ba9 JD |
1553 | if (unlikely(err)) |
1554 | break; | |
4735c98f JD |
1555 | } |
1556 | ||
4735c98f JD |
1557 | kfree(temp_client); |
1558 | return err; | |
1559 | } | |
1560 | ||
d44f19d5 JD |
1561 | int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr) |
1562 | { | |
1563 | return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
1564 | I2C_SMBUS_QUICK, NULL) >= 0; | |
1565 | } | |
1566 | EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read); | |
1567 | ||
12b5053a JD |
1568 | struct i2c_client * |
1569 | i2c_new_probed_device(struct i2c_adapter *adap, | |
1570 | struct i2c_board_info *info, | |
9a94241a JD |
1571 | unsigned short const *addr_list, |
1572 | int (*probe)(struct i2c_adapter *, unsigned short addr)) | |
12b5053a JD |
1573 | { |
1574 | int i; | |
1575 | ||
8031d79b | 1576 | if (!probe) |
9a94241a | 1577 | probe = i2c_default_probe; |
12b5053a | 1578 | |
12b5053a JD |
1579 | for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { |
1580 | /* Check address validity */ | |
656b8761 | 1581 | if (i2c_check_addr_validity(addr_list[i]) < 0) { |
12b5053a JD |
1582 | dev_warn(&adap->dev, "Invalid 7-bit address " |
1583 | "0x%02x\n", addr_list[i]); | |
1584 | continue; | |
1585 | } | |
1586 | ||
1587 | /* Check address availability */ | |
3b5f794b | 1588 | if (i2c_check_addr_busy(adap, addr_list[i])) { |
12b5053a JD |
1589 | dev_dbg(&adap->dev, "Address 0x%02x already in " |
1590 | "use, not probing\n", addr_list[i]); | |
1591 | continue; | |
1592 | } | |
1593 | ||
63e4e802 | 1594 | /* Test address responsiveness */ |
9a94241a | 1595 | if (probe(adap, addr_list[i])) |
63e4e802 | 1596 | break; |
12b5053a | 1597 | } |
12b5053a JD |
1598 | |
1599 | if (addr_list[i] == I2C_CLIENT_END) { | |
1600 | dev_dbg(&adap->dev, "Probing failed, no device found\n"); | |
1601 | return NULL; | |
1602 | } | |
1603 | ||
1604 | info->addr = addr_list[i]; | |
1605 | return i2c_new_device(adap, info); | |
1606 | } | |
1607 | EXPORT_SYMBOL_GPL(i2c_new_probed_device); | |
1608 | ||
d735b34d | 1609 | struct i2c_adapter *i2c_get_adapter(int nr) |
1da177e4 | 1610 | { |
1da177e4 | 1611 | struct i2c_adapter *adapter; |
438d6c2c | 1612 | |
caada32a | 1613 | mutex_lock(&core_lock); |
d735b34d | 1614 | adapter = idr_find(&i2c_adapter_idr, nr); |
a0920e10 MH |
1615 | if (adapter && !try_module_get(adapter->owner)) |
1616 | adapter = NULL; | |
1617 | ||
caada32a | 1618 | mutex_unlock(&core_lock); |
a0920e10 | 1619 | return adapter; |
1da177e4 | 1620 | } |
c0564606 | 1621 | EXPORT_SYMBOL(i2c_get_adapter); |
1da177e4 LT |
1622 | |
1623 | void i2c_put_adapter(struct i2c_adapter *adap) | |
1624 | { | |
1625 | module_put(adap->owner); | |
1626 | } | |
c0564606 | 1627 | EXPORT_SYMBOL(i2c_put_adapter); |
1da177e4 LT |
1628 | |
1629 | /* The SMBus parts */ | |
1630 | ||
438d6c2c | 1631 | #define POLY (0x1070U << 3) |
09b8ce0a | 1632 | static u8 crc8(u16 data) |
1da177e4 LT |
1633 | { |
1634 | int i; | |
438d6c2c | 1635 | |
7225acf4 | 1636 | for (i = 0; i < 8; i++) { |
438d6c2c | 1637 | if (data & 0x8000) |
1da177e4 LT |
1638 | data = data ^ POLY; |
1639 | data = data << 1; | |
1640 | } | |
1641 | return (u8)(data >> 8); | |
1642 | } | |
1643 | ||
421ef47b JD |
1644 | /* Incremental CRC8 over count bytes in the array pointed to by p */ |
1645 | static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count) | |
1da177e4 LT |
1646 | { |
1647 | int i; | |
1648 | ||
7225acf4 | 1649 | for (i = 0; i < count; i++) |
421ef47b | 1650 | crc = crc8((crc ^ p[i]) << 8); |
1da177e4 LT |
1651 | return crc; |
1652 | } | |
1653 | ||
421ef47b JD |
1654 | /* Assume a 7-bit address, which is reasonable for SMBus */ |
1655 | static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg) | |
1da177e4 | 1656 | { |
421ef47b JD |
1657 | /* The address will be sent first */ |
1658 | u8 addr = (msg->addr << 1) | !!(msg->flags & I2C_M_RD); | |
1659 | pec = i2c_smbus_pec(pec, &addr, 1); | |
1660 | ||
1661 | /* The data buffer follows */ | |
1662 | return i2c_smbus_pec(pec, msg->buf, msg->len); | |
1da177e4 LT |
1663 | } |
1664 | ||
421ef47b JD |
1665 | /* Used for write only transactions */ |
1666 | static inline void i2c_smbus_add_pec(struct i2c_msg *msg) | |
1da177e4 | 1667 | { |
421ef47b JD |
1668 | msg->buf[msg->len] = i2c_smbus_msg_pec(0, msg); |
1669 | msg->len++; | |
1da177e4 LT |
1670 | } |
1671 | ||
421ef47b JD |
1672 | /* Return <0 on CRC error |
1673 | If there was a write before this read (most cases) we need to take the | |
1674 | partial CRC from the write part into account. | |
1675 | Note that this function does modify the message (we need to decrease the | |
1676 | message length to hide the CRC byte from the caller). */ | |
1677 | static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg) | |
1da177e4 | 1678 | { |
421ef47b JD |
1679 | u8 rpec = msg->buf[--msg->len]; |
1680 | cpec = i2c_smbus_msg_pec(cpec, msg); | |
1da177e4 | 1681 | |
1da177e4 LT |
1682 | if (rpec != cpec) { |
1683 | pr_debug("i2c-core: Bad PEC 0x%02x vs. 0x%02x\n", | |
1684 | rpec, cpec); | |
24a5bb7b | 1685 | return -EBADMSG; |
1da177e4 | 1686 | } |
438d6c2c | 1687 | return 0; |
1da177e4 LT |
1688 | } |
1689 | ||
a1cdedac DB |
1690 | /** |
1691 | * i2c_smbus_read_byte - SMBus "receive byte" protocol | |
1692 | * @client: Handle to slave device | |
1693 | * | |
1694 | * This executes the SMBus "receive byte" protocol, returning negative errno | |
1695 | * else the byte received from the device. | |
1696 | */ | |
0cc43a18 | 1697 | s32 i2c_smbus_read_byte(const struct i2c_client *client) |
1da177e4 LT |
1698 | { |
1699 | union i2c_smbus_data data; | |
24a5bb7b DB |
1700 | int status; |
1701 | ||
1702 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1703 | I2C_SMBUS_READ, 0, | |
1704 | I2C_SMBUS_BYTE, &data); | |
1705 | return (status < 0) ? status : data.byte; | |
1da177e4 | 1706 | } |
c0564606 | 1707 | EXPORT_SYMBOL(i2c_smbus_read_byte); |
1da177e4 | 1708 | |
a1cdedac DB |
1709 | /** |
1710 | * i2c_smbus_write_byte - SMBus "send byte" protocol | |
1711 | * @client: Handle to slave device | |
1712 | * @value: Byte to be sent | |
1713 | * | |
1714 | * This executes the SMBus "send byte" protocol, returning negative errno | |
1715 | * else zero on success. | |
1716 | */ | |
0cc43a18 | 1717 | s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value) |
1da177e4 | 1718 | { |
7225acf4 | 1719 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
421ef47b | 1720 | I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL); |
1da177e4 | 1721 | } |
c0564606 | 1722 | EXPORT_SYMBOL(i2c_smbus_write_byte); |
1da177e4 | 1723 | |
a1cdedac DB |
1724 | /** |
1725 | * i2c_smbus_read_byte_data - SMBus "read byte" protocol | |
1726 | * @client: Handle to slave device | |
1727 | * @command: Byte interpreted by slave | |
1728 | * | |
1729 | * This executes the SMBus "read byte" protocol, returning negative errno | |
1730 | * else a data byte received from the device. | |
1731 | */ | |
0cc43a18 | 1732 | s32 i2c_smbus_read_byte_data(const struct i2c_client *client, u8 command) |
1da177e4 LT |
1733 | { |
1734 | union i2c_smbus_data data; | |
24a5bb7b DB |
1735 | int status; |
1736 | ||
1737 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1738 | I2C_SMBUS_READ, command, | |
1739 | I2C_SMBUS_BYTE_DATA, &data); | |
1740 | return (status < 0) ? status : data.byte; | |
1da177e4 | 1741 | } |
c0564606 | 1742 | EXPORT_SYMBOL(i2c_smbus_read_byte_data); |
1da177e4 | 1743 | |
a1cdedac DB |
1744 | /** |
1745 | * i2c_smbus_write_byte_data - SMBus "write byte" protocol | |
1746 | * @client: Handle to slave device | |
1747 | * @command: Byte interpreted by slave | |
1748 | * @value: Byte being written | |
1749 | * | |
1750 | * This executes the SMBus "write byte" protocol, returning negative errno | |
1751 | * else zero on success. | |
1752 | */ | |
0cc43a18 JD |
1753 | s32 i2c_smbus_write_byte_data(const struct i2c_client *client, u8 command, |
1754 | u8 value) | |
1da177e4 LT |
1755 | { |
1756 | union i2c_smbus_data data; | |
1757 | data.byte = value; | |
7225acf4 FH |
1758 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
1759 | I2C_SMBUS_WRITE, command, | |
1760 | I2C_SMBUS_BYTE_DATA, &data); | |
1da177e4 | 1761 | } |
c0564606 | 1762 | EXPORT_SYMBOL(i2c_smbus_write_byte_data); |
1da177e4 | 1763 | |
a1cdedac DB |
1764 | /** |
1765 | * i2c_smbus_read_word_data - SMBus "read word" protocol | |
1766 | * @client: Handle to slave device | |
1767 | * @command: Byte interpreted by slave | |
1768 | * | |
1769 | * This executes the SMBus "read word" protocol, returning negative errno | |
1770 | * else a 16-bit unsigned "word" received from the device. | |
1771 | */ | |
0cc43a18 | 1772 | s32 i2c_smbus_read_word_data(const struct i2c_client *client, u8 command) |
1da177e4 LT |
1773 | { |
1774 | union i2c_smbus_data data; | |
24a5bb7b DB |
1775 | int status; |
1776 | ||
1777 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1778 | I2C_SMBUS_READ, command, | |
1779 | I2C_SMBUS_WORD_DATA, &data); | |
1780 | return (status < 0) ? status : data.word; | |
1da177e4 | 1781 | } |
c0564606 | 1782 | EXPORT_SYMBOL(i2c_smbus_read_word_data); |
1da177e4 | 1783 | |
a1cdedac DB |
1784 | /** |
1785 | * i2c_smbus_write_word_data - SMBus "write word" protocol | |
1786 | * @client: Handle to slave device | |
1787 | * @command: Byte interpreted by slave | |
1788 | * @value: 16-bit "word" being written | |
1789 | * | |
1790 | * This executes the SMBus "write word" protocol, returning negative errno | |
1791 | * else zero on success. | |
1792 | */ | |
0cc43a18 JD |
1793 | s32 i2c_smbus_write_word_data(const struct i2c_client *client, u8 command, |
1794 | u16 value) | |
1da177e4 LT |
1795 | { |
1796 | union i2c_smbus_data data; | |
1797 | data.word = value; | |
7225acf4 FH |
1798 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
1799 | I2C_SMBUS_WRITE, command, | |
1800 | I2C_SMBUS_WORD_DATA, &data); | |
1da177e4 | 1801 | } |
c0564606 | 1802 | EXPORT_SYMBOL(i2c_smbus_write_word_data); |
1da177e4 | 1803 | |
596c88f4 PM |
1804 | /** |
1805 | * i2c_smbus_process_call - SMBus "process call" protocol | |
1806 | * @client: Handle to slave device | |
1807 | * @command: Byte interpreted by slave | |
1808 | * @value: 16-bit "word" being written | |
1809 | * | |
1810 | * This executes the SMBus "process call" protocol, returning negative errno | |
1811 | * else a 16-bit unsigned "word" received from the device. | |
1812 | */ | |
0cc43a18 JD |
1813 | s32 i2c_smbus_process_call(const struct i2c_client *client, u8 command, |
1814 | u16 value) | |
596c88f4 PM |
1815 | { |
1816 | union i2c_smbus_data data; | |
1817 | int status; | |
1818 | data.word = value; | |
1819 | ||
1820 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1821 | I2C_SMBUS_WRITE, command, | |
1822 | I2C_SMBUS_PROC_CALL, &data); | |
1823 | return (status < 0) ? status : data.word; | |
1824 | } | |
1825 | EXPORT_SYMBOL(i2c_smbus_process_call); | |
1826 | ||
a64ec07d | 1827 | /** |
a1cdedac | 1828 | * i2c_smbus_read_block_data - SMBus "block read" protocol |
a64ec07d | 1829 | * @client: Handle to slave device |
a1cdedac | 1830 | * @command: Byte interpreted by slave |
a64ec07d DB |
1831 | * @values: Byte array into which data will be read; big enough to hold |
1832 | * the data returned by the slave. SMBus allows at most 32 bytes. | |
1833 | * | |
a1cdedac DB |
1834 | * This executes the SMBus "block read" protocol, returning negative errno |
1835 | * else the number of data bytes in the slave's response. | |
a64ec07d DB |
1836 | * |
1837 | * Note that using this function requires that the client's adapter support | |
1838 | * the I2C_FUNC_SMBUS_READ_BLOCK_DATA functionality. Not all adapter drivers | |
1839 | * support this; its emulation through I2C messaging relies on a specific | |
1840 | * mechanism (I2C_M_RECV_LEN) which may not be implemented. | |
1841 | */ | |
0cc43a18 | 1842 | s32 i2c_smbus_read_block_data(const struct i2c_client *client, u8 command, |
b86a1bc8 JD |
1843 | u8 *values) |
1844 | { | |
1845 | union i2c_smbus_data data; | |
24a5bb7b | 1846 | int status; |
b86a1bc8 | 1847 | |
24a5bb7b DB |
1848 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
1849 | I2C_SMBUS_READ, command, | |
1850 | I2C_SMBUS_BLOCK_DATA, &data); | |
1851 | if (status) | |
1852 | return status; | |
b86a1bc8 JD |
1853 | |
1854 | memcpy(values, &data.block[1], data.block[0]); | |
1855 | return data.block[0]; | |
1856 | } | |
1857 | EXPORT_SYMBOL(i2c_smbus_read_block_data); | |
1858 | ||
a1cdedac DB |
1859 | /** |
1860 | * i2c_smbus_write_block_data - SMBus "block write" protocol | |
1861 | * @client: Handle to slave device | |
1862 | * @command: Byte interpreted by slave | |
1863 | * @length: Size of data block; SMBus allows at most 32 bytes | |
1864 | * @values: Byte array which will be written. | |
1865 | * | |
1866 | * This executes the SMBus "block write" protocol, returning negative errno | |
1867 | * else zero on success. | |
1868 | */ | |
0cc43a18 | 1869 | s32 i2c_smbus_write_block_data(const struct i2c_client *client, u8 command, |
46f5ed75 | 1870 | u8 length, const u8 *values) |
1da177e4 LT |
1871 | { |
1872 | union i2c_smbus_data data; | |
7656032b | 1873 | |
1da177e4 LT |
1874 | if (length > I2C_SMBUS_BLOCK_MAX) |
1875 | length = I2C_SMBUS_BLOCK_MAX; | |
1da177e4 | 1876 | data.block[0] = length; |
7656032b | 1877 | memcpy(&data.block[1], values, length); |
7225acf4 FH |
1878 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
1879 | I2C_SMBUS_WRITE, command, | |
1880 | I2C_SMBUS_BLOCK_DATA, &data); | |
1da177e4 | 1881 | } |
c0564606 | 1882 | EXPORT_SYMBOL(i2c_smbus_write_block_data); |
1da177e4 LT |
1883 | |
1884 | /* Returns the number of read bytes */ | |
0cc43a18 | 1885 | s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, u8 command, |
4b2643d7 | 1886 | u8 length, u8 *values) |
1da177e4 LT |
1887 | { |
1888 | union i2c_smbus_data data; | |
24a5bb7b | 1889 | int status; |
7656032b | 1890 | |
4b2643d7 JD |
1891 | if (length > I2C_SMBUS_BLOCK_MAX) |
1892 | length = I2C_SMBUS_BLOCK_MAX; | |
1893 | data.block[0] = length; | |
24a5bb7b DB |
1894 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
1895 | I2C_SMBUS_READ, command, | |
1896 | I2C_SMBUS_I2C_BLOCK_DATA, &data); | |
1897 | if (status < 0) | |
1898 | return status; | |
7656032b JD |
1899 | |
1900 | memcpy(values, &data.block[1], data.block[0]); | |
1901 | return data.block[0]; | |
1da177e4 | 1902 | } |
c0564606 | 1903 | EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data); |
1da177e4 | 1904 | |
0cc43a18 | 1905 | s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, u8 command, |
46f5ed75 | 1906 | u8 length, const u8 *values) |
21bbd691 JD |
1907 | { |
1908 | union i2c_smbus_data data; | |
1909 | ||
1910 | if (length > I2C_SMBUS_BLOCK_MAX) | |
1911 | length = I2C_SMBUS_BLOCK_MAX; | |
1912 | data.block[0] = length; | |
1913 | memcpy(data.block + 1, values, length); | |
1914 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1915 | I2C_SMBUS_WRITE, command, | |
1916 | I2C_SMBUS_I2C_BLOCK_DATA, &data); | |
1917 | } | |
c0564606 | 1918 | EXPORT_SYMBOL(i2c_smbus_write_i2c_block_data); |
21bbd691 | 1919 | |
438d6c2c | 1920 | /* Simulate a SMBus command using the i2c protocol |
1da177e4 | 1921 | No checking of parameters is done! */ |
7225acf4 FH |
1922 | static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, |
1923 | unsigned short flags, | |
1924 | char read_write, u8 command, int size, | |
1925 | union i2c_smbus_data *data) | |
1da177e4 LT |
1926 | { |
1927 | /* So we need to generate a series of msgs. In the case of writing, we | |
1928 | need to use only one message; when reading, we need two. We initialize | |
1929 | most things with sane defaults, to keep the code below somewhat | |
1930 | simpler. */ | |
5c50d188 HI |
1931 | unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3]; |
1932 | unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2]; | |
7225acf4 | 1933 | int num = read_write == I2C_SMBUS_READ ? 2 : 1; |
438d6c2c | 1934 | struct i2c_msg msg[2] = { { addr, flags, 1, msgbuf0 }, |
1da177e4 LT |
1935 | { addr, flags | I2C_M_RD, 0, msgbuf1 } |
1936 | }; | |
1937 | int i; | |
421ef47b | 1938 | u8 partial_pec = 0; |
24a5bb7b | 1939 | int status; |
1da177e4 LT |
1940 | |
1941 | msgbuf0[0] = command; | |
7225acf4 | 1942 | switch (size) { |
1da177e4 LT |
1943 | case I2C_SMBUS_QUICK: |
1944 | msg[0].len = 0; | |
1945 | /* Special case: The read/write field is used as data */ | |
f29d2e02 RK |
1946 | msg[0].flags = flags | (read_write == I2C_SMBUS_READ ? |
1947 | I2C_M_RD : 0); | |
1da177e4 LT |
1948 | num = 1; |
1949 | break; | |
1950 | case I2C_SMBUS_BYTE: | |
1951 | if (read_write == I2C_SMBUS_READ) { | |
1952 | /* Special case: only a read! */ | |
1953 | msg[0].flags = I2C_M_RD | flags; | |
1954 | num = 1; | |
1955 | } | |
1956 | break; | |
1957 | case I2C_SMBUS_BYTE_DATA: | |
1958 | if (read_write == I2C_SMBUS_READ) | |
1959 | msg[1].len = 1; | |
1960 | else { | |
1961 | msg[0].len = 2; | |
1962 | msgbuf0[1] = data->byte; | |
1963 | } | |
1964 | break; | |
1965 | case I2C_SMBUS_WORD_DATA: | |
1966 | if (read_write == I2C_SMBUS_READ) | |
1967 | msg[1].len = 2; | |
1968 | else { | |
7225acf4 | 1969 | msg[0].len = 3; |
1da177e4 | 1970 | msgbuf0[1] = data->word & 0xff; |
7eff82c8 | 1971 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
1972 | } |
1973 | break; | |
1974 | case I2C_SMBUS_PROC_CALL: | |
1975 | num = 2; /* Special case */ | |
1976 | read_write = I2C_SMBUS_READ; | |
1977 | msg[0].len = 3; | |
1978 | msg[1].len = 2; | |
1979 | msgbuf0[1] = data->word & 0xff; | |
7eff82c8 | 1980 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
1981 | break; |
1982 | case I2C_SMBUS_BLOCK_DATA: | |
1da177e4 | 1983 | if (read_write == I2C_SMBUS_READ) { |
209d27c3 JD |
1984 | msg[1].flags |= I2C_M_RECV_LEN; |
1985 | msg[1].len = 1; /* block length will be added by | |
1986 | the underlying bus driver */ | |
1da177e4 LT |
1987 | } else { |
1988 | msg[0].len = data->block[0] + 2; | |
1989 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 2) { | |
24a5bb7b DB |
1990 | dev_err(&adapter->dev, |
1991 | "Invalid block write size %d\n", | |
1992 | data->block[0]); | |
1993 | return -EINVAL; | |
1da177e4 | 1994 | } |
5c50d188 | 1995 | for (i = 1; i < msg[0].len; i++) |
1da177e4 LT |
1996 | msgbuf0[i] = data->block[i-1]; |
1997 | } | |
1998 | break; | |
1999 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
209d27c3 JD |
2000 | num = 2; /* Another special case */ |
2001 | read_write = I2C_SMBUS_READ; | |
2002 | if (data->block[0] > I2C_SMBUS_BLOCK_MAX) { | |
24a5bb7b DB |
2003 | dev_err(&adapter->dev, |
2004 | "Invalid block write size %d\n", | |
209d27c3 | 2005 | data->block[0]); |
24a5bb7b | 2006 | return -EINVAL; |
209d27c3 JD |
2007 | } |
2008 | msg[0].len = data->block[0] + 2; | |
2009 | for (i = 1; i < msg[0].len; i++) | |
2010 | msgbuf0[i] = data->block[i-1]; | |
2011 | msg[1].flags |= I2C_M_RECV_LEN; | |
2012 | msg[1].len = 1; /* block length will be added by | |
2013 | the underlying bus driver */ | |
2014 | break; | |
1da177e4 LT |
2015 | case I2C_SMBUS_I2C_BLOCK_DATA: |
2016 | if (read_write == I2C_SMBUS_READ) { | |
4b2643d7 | 2017 | msg[1].len = data->block[0]; |
1da177e4 LT |
2018 | } else { |
2019 | msg[0].len = data->block[0] + 1; | |
30dac746 | 2020 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 1) { |
24a5bb7b DB |
2021 | dev_err(&adapter->dev, |
2022 | "Invalid block write size %d\n", | |
2023 | data->block[0]); | |
2024 | return -EINVAL; | |
1da177e4 LT |
2025 | } |
2026 | for (i = 1; i <= data->block[0]; i++) | |
2027 | msgbuf0[i] = data->block[i]; | |
2028 | } | |
2029 | break; | |
2030 | default: | |
24a5bb7b DB |
2031 | dev_err(&adapter->dev, "Unsupported transaction %d\n", size); |
2032 | return -EOPNOTSUPP; | |
1da177e4 LT |
2033 | } |
2034 | ||
421ef47b JD |
2035 | i = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK |
2036 | && size != I2C_SMBUS_I2C_BLOCK_DATA); | |
2037 | if (i) { | |
2038 | /* Compute PEC if first message is a write */ | |
2039 | if (!(msg[0].flags & I2C_M_RD)) { | |
438d6c2c | 2040 | if (num == 1) /* Write only */ |
421ef47b JD |
2041 | i2c_smbus_add_pec(&msg[0]); |
2042 | else /* Write followed by read */ | |
2043 | partial_pec = i2c_smbus_msg_pec(0, &msg[0]); | |
2044 | } | |
2045 | /* Ask for PEC if last message is a read */ | |
2046 | if (msg[num-1].flags & I2C_M_RD) | |
438d6c2c | 2047 | msg[num-1].len++; |
421ef47b JD |
2048 | } |
2049 | ||
24a5bb7b DB |
2050 | status = i2c_transfer(adapter, msg, num); |
2051 | if (status < 0) | |
2052 | return status; | |
1da177e4 | 2053 | |
421ef47b JD |
2054 | /* Check PEC if last message is a read */ |
2055 | if (i && (msg[num-1].flags & I2C_M_RD)) { | |
24a5bb7b DB |
2056 | status = i2c_smbus_check_pec(partial_pec, &msg[num-1]); |
2057 | if (status < 0) | |
2058 | return status; | |
421ef47b JD |
2059 | } |
2060 | ||
1da177e4 | 2061 | if (read_write == I2C_SMBUS_READ) |
7225acf4 FH |
2062 | switch (size) { |
2063 | case I2C_SMBUS_BYTE: | |
2064 | data->byte = msgbuf0[0]; | |
2065 | break; | |
2066 | case I2C_SMBUS_BYTE_DATA: | |
2067 | data->byte = msgbuf1[0]; | |
2068 | break; | |
2069 | case I2C_SMBUS_WORD_DATA: | |
2070 | case I2C_SMBUS_PROC_CALL: | |
2071 | data->word = msgbuf1[0] | (msgbuf1[1] << 8); | |
2072 | break; | |
2073 | case I2C_SMBUS_I2C_BLOCK_DATA: | |
2074 | for (i = 0; i < data->block[0]; i++) | |
2075 | data->block[i+1] = msgbuf1[i]; | |
2076 | break; | |
2077 | case I2C_SMBUS_BLOCK_DATA: | |
2078 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
2079 | for (i = 0; i < msgbuf1[0] + 1; i++) | |
2080 | data->block[i] = msgbuf1[i]; | |
2081 | break; | |
1da177e4 LT |
2082 | } |
2083 | return 0; | |
2084 | } | |
2085 | ||
a1cdedac DB |
2086 | /** |
2087 | * i2c_smbus_xfer - execute SMBus protocol operations | |
2088 | * @adapter: Handle to I2C bus | |
2089 | * @addr: Address of SMBus slave on that bus | |
2090 | * @flags: I2C_CLIENT_* flags (usually zero or I2C_CLIENT_PEC) | |
2091 | * @read_write: I2C_SMBUS_READ or I2C_SMBUS_WRITE | |
2092 | * @command: Byte interpreted by slave, for protocols which use such bytes | |
2093 | * @protocol: SMBus protocol operation to execute, such as I2C_SMBUS_PROC_CALL | |
2094 | * @data: Data to be read or written | |
2095 | * | |
2096 | * This executes an SMBus protocol operation, and returns a negative | |
2097 | * errno code else zero on success. | |
2098 | */ | |
09b8ce0a | 2099 | s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags, |
a1cdedac | 2100 | char read_write, u8 command, int protocol, |
09b8ce0a | 2101 | union i2c_smbus_data *data) |
1da177e4 | 2102 | { |
66b650f0 CW |
2103 | unsigned long orig_jiffies; |
2104 | int try; | |
1da177e4 | 2105 | s32 res; |
1da177e4 LT |
2106 | |
2107 | flags &= I2C_M_TEN | I2C_CLIENT_PEC; | |
1da177e4 LT |
2108 | |
2109 | if (adapter->algo->smbus_xfer) { | |
fe61e07e | 2110 | i2c_lock_adapter(adapter); |
66b650f0 CW |
2111 | |
2112 | /* Retry automatically on arbitration loss */ | |
2113 | orig_jiffies = jiffies; | |
2114 | for (res = 0, try = 0; try <= adapter->retries; try++) { | |
2115 | res = adapter->algo->smbus_xfer(adapter, addr, flags, | |
2116 | read_write, command, | |
2117 | protocol, data); | |
2118 | if (res != -EAGAIN) | |
2119 | break; | |
2120 | if (time_after(jiffies, | |
2121 | orig_jiffies + adapter->timeout)) | |
2122 | break; | |
2123 | } | |
fe61e07e | 2124 | i2c_unlock_adapter(adapter); |
1da177e4 | 2125 | } else |
7225acf4 | 2126 | res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write, |
a1cdedac | 2127 | command, protocol, data); |
1da177e4 | 2128 | |
1da177e4 LT |
2129 | return res; |
2130 | } | |
1da177e4 | 2131 | EXPORT_SYMBOL(i2c_smbus_xfer); |
1da177e4 LT |
2132 | |
2133 | MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); | |
2134 | MODULE_DESCRIPTION("I2C-Bus main module"); | |
2135 | MODULE_LICENSE("GPL"); |