9638ad4dc635dddce4e67806e3d32b0524fcf10a
[linux-3.10.git] / drivers / leds / leds-lp55xx-common.c
1 /*
2  * LP5521/LP5523/LP55231 Common Driver
3  *
4  * Copyright 2012 Texas Instruments
5  *
6  * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  * Derived from leds-lp5521.c, leds-lp5523.c
13  */
14
15 #include <linux/delay.h>
16 #include <linux/firmware.h>
17 #include <linux/i2c.h>
18 #include <linux/leds.h>
19 #include <linux/module.h>
20 #include <linux/platform_data/leds-lp55xx.h>
21
22 #include "leds-lp55xx-common.h"
23
24 static struct lp55xx_led *cdev_to_lp55xx_led(struct led_classdev *cdev)
25 {
26         return container_of(cdev, struct lp55xx_led, cdev);
27 }
28
29 static struct lp55xx_led *dev_to_lp55xx_led(struct device *dev)
30 {
31         return cdev_to_lp55xx_led(dev_get_drvdata(dev));
32 }
33
34 static void lp55xx_reset_device(struct lp55xx_chip *chip)
35 {
36         struct lp55xx_device_config *cfg = chip->cfg;
37         u8 addr = cfg->reset.addr;
38         u8 val  = cfg->reset.val;
39
40         /* no error checking here because no ACK from the device after reset */
41         lp55xx_write(chip, addr, val);
42 }
43
44 static int lp55xx_detect_device(struct lp55xx_chip *chip)
45 {
46         struct lp55xx_device_config *cfg = chip->cfg;
47         u8 addr = cfg->enable.addr;
48         u8 val  = cfg->enable.val;
49         int ret;
50
51         ret = lp55xx_write(chip, addr, val);
52         if (ret)
53                 return ret;
54
55         usleep_range(1000, 2000);
56
57         ret = lp55xx_read(chip, addr, &val);
58         if (ret)
59                 return ret;
60
61         if (val != cfg->enable.val)
62                 return -ENODEV;
63
64         return 0;
65 }
66
67 static int lp55xx_post_init_device(struct lp55xx_chip *chip)
68 {
69         struct lp55xx_device_config *cfg = chip->cfg;
70
71         if (!cfg->post_init_device)
72                 return 0;
73
74         return cfg->post_init_device(chip);
75 }
76
77 static ssize_t lp55xx_show_current(struct device *dev,
78                             struct device_attribute *attr,
79                             char *buf)
80 {
81         struct lp55xx_led *led = dev_to_lp55xx_led(dev);
82
83         return sprintf(buf, "%d\n", led->led_current);
84 }
85
86 static ssize_t lp55xx_store_current(struct device *dev,
87                              struct device_attribute *attr,
88                              const char *buf, size_t len)
89 {
90         struct lp55xx_led *led = dev_to_lp55xx_led(dev);
91         struct lp55xx_chip *chip = led->chip;
92         unsigned long curr;
93
94         if (kstrtoul(buf, 0, &curr))
95                 return -EINVAL;
96
97         if (curr > led->max_current)
98                 return -EINVAL;
99
100         if (!chip->cfg->set_led_current)
101                 return len;
102
103         mutex_lock(&chip->lock);
104         chip->cfg->set_led_current(led, (u8)curr);
105         mutex_unlock(&chip->lock);
106
107         return len;
108 }
109
110 static ssize_t lp55xx_show_max_current(struct device *dev,
111                             struct device_attribute *attr,
112                             char *buf)
113 {
114         struct lp55xx_led *led = dev_to_lp55xx_led(dev);
115
116         return sprintf(buf, "%d\n", led->max_current);
117 }
118
119 static DEVICE_ATTR(led_current, S_IRUGO | S_IWUSR, lp55xx_show_current,
120                 lp55xx_store_current);
121 static DEVICE_ATTR(max_current, S_IRUGO , lp55xx_show_max_current, NULL);
122
123 static struct attribute *lp55xx_led_attributes[] = {
124         &dev_attr_led_current.attr,
125         &dev_attr_max_current.attr,
126         NULL,
127 };
128
129 static struct attribute_group lp55xx_led_attr_group = {
130         .attrs = lp55xx_led_attributes
131 };
132
133 static void lp55xx_set_brightness(struct led_classdev *cdev,
134                              enum led_brightness brightness)
135 {
136         struct lp55xx_led *led = cdev_to_lp55xx_led(cdev);
137
138         led->brightness = (u8)brightness;
139         schedule_work(&led->brightness_work);
140 }
141
142 static int lp55xx_init_led(struct lp55xx_led *led,
143                         struct lp55xx_chip *chip, int chan)
144 {
145         struct lp55xx_platform_data *pdata = chip->pdata;
146         struct lp55xx_device_config *cfg = chip->cfg;
147         struct device *dev = &chip->cl->dev;
148         char name[32];
149         int ret;
150         int max_channel = cfg->max_channel;
151
152         if (chan >= max_channel) {
153                 dev_err(dev, "invalid channel: %d / %d\n", chan, max_channel);
154                 return -EINVAL;
155         }
156
157         if (pdata->led_config[chan].led_current == 0)
158                 return 0;
159
160         led->led_current = pdata->led_config[chan].led_current;
161         led->max_current = pdata->led_config[chan].max_current;
162         led->chan_nr = pdata->led_config[chan].chan_nr;
163
164         if (led->chan_nr >= max_channel) {
165                 dev_err(dev, "Use channel numbers between 0 and %d\n",
166                         max_channel - 1);
167                 return -EINVAL;
168         }
169
170         led->cdev.brightness_set = lp55xx_set_brightness;
171
172         if (pdata->led_config[chan].name) {
173                 led->cdev.name = pdata->led_config[chan].name;
174         } else {
175                 snprintf(name, sizeof(name), "%s:channel%d",
176                         pdata->label ? : chip->cl->name, chan);
177                 led->cdev.name = name;
178         }
179
180         /*
181          * register led class device for each channel and
182          * add device attributes
183          */
184
185         ret = led_classdev_register(dev, &led->cdev);
186         if (ret) {
187                 dev_err(dev, "led register err: %d\n", ret);
188                 return ret;
189         }
190
191         ret = sysfs_create_group(&led->cdev.dev->kobj, &lp55xx_led_attr_group);
192         if (ret) {
193                 dev_err(dev, "led sysfs err: %d\n", ret);
194                 led_classdev_unregister(&led->cdev);
195                 return ret;
196         }
197
198         return 0;
199 }
200
201 static void lp55xx_firmware_loaded(const struct firmware *fw, void *context)
202 {
203         struct lp55xx_chip *chip = context;
204         struct device *dev = &chip->cl->dev;
205
206         if (!fw) {
207                 dev_err(dev, "firmware request failed\n");
208                 goto out;
209         }
210
211         /* handling firmware data is chip dependent */
212         mutex_lock(&chip->lock);
213
214         chip->fw = fw;
215         if (chip->cfg->firmware_cb)
216                 chip->cfg->firmware_cb(chip);
217
218         mutex_unlock(&chip->lock);
219
220 out:
221         /* firmware should be released for other channel use */
222         release_firmware(chip->fw);
223 }
224
225 static int lp55xx_request_firmware(struct lp55xx_chip *chip)
226 {
227         const char *name = chip->cl->name;
228         struct device *dev = &chip->cl->dev;
229
230         return request_firmware_nowait(THIS_MODULE, true, name, dev,
231                                 GFP_KERNEL, chip, lp55xx_firmware_loaded);
232 }
233
234 static ssize_t lp55xx_show_engine_select(struct device *dev,
235                             struct device_attribute *attr,
236                             char *buf)
237 {
238         struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
239         struct lp55xx_chip *chip = led->chip;
240
241         return sprintf(buf, "%d\n", chip->engine_idx);
242 }
243
244 static ssize_t lp55xx_store_engine_select(struct device *dev,
245                              struct device_attribute *attr,
246                              const char *buf, size_t len)
247 {
248         struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
249         struct lp55xx_chip *chip = led->chip;
250         unsigned long val;
251         int ret;
252
253         if (kstrtoul(buf, 0, &val))
254                 return -EINVAL;
255
256         /* select the engine to be run */
257
258         switch (val) {
259         case LP55XX_ENGINE_1:
260         case LP55XX_ENGINE_2:
261         case LP55XX_ENGINE_3:
262                 mutex_lock(&chip->lock);
263                 chip->engine_idx = val;
264                 ret = lp55xx_request_firmware(chip);
265                 mutex_unlock(&chip->lock);
266                 break;
267         default:
268                 dev_err(dev, "%lu: invalid engine index. (1, 2, 3)\n", val);
269                 return -EINVAL;
270         }
271
272         if (ret) {
273                 dev_err(dev, "request firmware err: %d\n", ret);
274                 return ret;
275         }
276
277         return len;
278 }
279
280 static inline void lp55xx_run_engine(struct lp55xx_chip *chip, bool start)
281 {
282         if (chip->cfg->run_engine)
283                 chip->cfg->run_engine(chip, start);
284 }
285
286 static ssize_t lp55xx_store_engine_run(struct device *dev,
287                              struct device_attribute *attr,
288                              const char *buf, size_t len)
289 {
290         struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
291         struct lp55xx_chip *chip = led->chip;
292         unsigned long val;
293
294         if (kstrtoul(buf, 0, &val))
295                 return -EINVAL;
296
297         /* run or stop the selected engine */
298
299         if (val <= 0) {
300                 lp55xx_run_engine(chip, false);
301                 return len;
302         }
303
304         mutex_lock(&chip->lock);
305         lp55xx_run_engine(chip, true);
306         mutex_unlock(&chip->lock);
307
308         return len;
309 }
310
311 static DEVICE_ATTR(select_engine, S_IRUGO | S_IWUSR,
312                    lp55xx_show_engine_select, lp55xx_store_engine_select);
313 static DEVICE_ATTR(run_engine, S_IWUSR, NULL, lp55xx_store_engine_run);
314
315 static struct attribute *lp55xx_engine_attributes[] = {
316         &dev_attr_select_engine.attr,
317         &dev_attr_run_engine.attr,
318         NULL,
319 };
320
321 static const struct attribute_group lp55xx_engine_attr_group = {
322         .attrs = lp55xx_engine_attributes,
323 };
324
325 int lp55xx_write(struct lp55xx_chip *chip, u8 reg, u8 val)
326 {
327         return i2c_smbus_write_byte_data(chip->cl, reg, val);
328 }
329 EXPORT_SYMBOL_GPL(lp55xx_write);
330
331 int lp55xx_read(struct lp55xx_chip *chip, u8 reg, u8 *val)
332 {
333         s32 ret;
334
335         ret = i2c_smbus_read_byte_data(chip->cl, reg);
336         if (ret < 0)
337                 return ret;
338
339         *val = ret;
340         return 0;
341 }
342 EXPORT_SYMBOL_GPL(lp55xx_read);
343
344 int lp55xx_update_bits(struct lp55xx_chip *chip, u8 reg, u8 mask, u8 val)
345 {
346         int ret;
347         u8 tmp;
348
349         ret = lp55xx_read(chip, reg, &tmp);
350         if (ret)
351                 return ret;
352
353         tmp &= ~mask;
354         tmp |= val & mask;
355
356         return lp55xx_write(chip, reg, tmp);
357 }
358 EXPORT_SYMBOL_GPL(lp55xx_update_bits);
359
360 int lp55xx_init_device(struct lp55xx_chip *chip)
361 {
362         struct lp55xx_platform_data *pdata;
363         struct lp55xx_device_config *cfg;
364         struct device *dev = &chip->cl->dev;
365         int ret = 0;
366
367         WARN_ON(!chip);
368
369         pdata = chip->pdata;
370         cfg = chip->cfg;
371
372         if (!pdata || !cfg)
373                 return -EINVAL;
374
375         if (pdata->setup_resources) {
376                 ret = pdata->setup_resources();
377                 if (ret < 0) {
378                         dev_err(dev, "setup resoure err: %d\n", ret);
379                         goto err;
380                 }
381         }
382
383         if (pdata->enable) {
384                 pdata->enable(0);
385                 usleep_range(1000, 2000); /* Keep enable down at least 1ms */
386                 pdata->enable(1);
387                 usleep_range(1000, 2000); /* 500us abs min. */
388         }
389
390         lp55xx_reset_device(chip);
391
392         /*
393          * Exact value is not available. 10 - 20ms
394          * appears to be enough for reset.
395          */
396         usleep_range(10000, 20000);
397
398         ret = lp55xx_detect_device(chip);
399         if (ret) {
400                 dev_err(dev, "device detection err: %d\n", ret);
401                 goto err;
402         }
403
404         /* chip specific initialization */
405         ret = lp55xx_post_init_device(chip);
406         if (ret) {
407                 dev_err(dev, "post init device err: %d\n", ret);
408                 goto err_post_init;
409         }
410
411         return 0;
412
413 err_post_init:
414         lp55xx_deinit_device(chip);
415 err:
416         return ret;
417 }
418 EXPORT_SYMBOL_GPL(lp55xx_init_device);
419
420 void lp55xx_deinit_device(struct lp55xx_chip *chip)
421 {
422         struct lp55xx_platform_data *pdata = chip->pdata;
423
424         if (pdata->enable)
425                 pdata->enable(0);
426
427         if (pdata->release_resources)
428                 pdata->release_resources();
429 }
430 EXPORT_SYMBOL_GPL(lp55xx_deinit_device);
431
432 int lp55xx_register_leds(struct lp55xx_led *led, struct lp55xx_chip *chip)
433 {
434         struct lp55xx_platform_data *pdata = chip->pdata;
435         struct lp55xx_device_config *cfg = chip->cfg;
436         int num_channels = pdata->num_channels;
437         struct lp55xx_led *each;
438         u8 led_current;
439         int ret;
440         int i;
441
442         if (!cfg->brightness_work_fn) {
443                 dev_err(&chip->cl->dev, "empty brightness configuration\n");
444                 return -EINVAL;
445         }
446
447         for (i = 0; i < num_channels; i++) {
448
449                 /* do not initialize channels that are not connected */
450                 if (pdata->led_config[i].led_current == 0)
451                         continue;
452
453                 led_current = pdata->led_config[i].led_current;
454                 each = led + i;
455                 ret = lp55xx_init_led(each, chip, i);
456                 if (ret)
457                         goto err_init_led;
458
459                 INIT_WORK(&each->brightness_work, cfg->brightness_work_fn);
460
461                 chip->num_leds++;
462                 each->chip = chip;
463
464                 /* setting led current at each channel */
465                 if (cfg->set_led_current)
466                         cfg->set_led_current(each, led_current);
467         }
468
469         return 0;
470
471 err_init_led:
472         lp55xx_unregister_leds(led, chip);
473         return ret;
474 }
475 EXPORT_SYMBOL_GPL(lp55xx_register_leds);
476
477 void lp55xx_unregister_leds(struct lp55xx_led *led, struct lp55xx_chip *chip)
478 {
479         int i;
480         struct lp55xx_led *each;
481         struct kobject *kobj;
482
483         for (i = 0; i < chip->num_leds; i++) {
484                 each = led + i;
485                 kobj = &led->cdev.dev->kobj;
486                 sysfs_remove_group(kobj, &lp55xx_led_attr_group);
487                 led_classdev_unregister(&each->cdev);
488                 flush_work(&each->brightness_work);
489         }
490 }
491 EXPORT_SYMBOL_GPL(lp55xx_unregister_leds);
492
493 int lp55xx_register_sysfs(struct lp55xx_chip *chip)
494 {
495         struct device *dev = &chip->cl->dev;
496         struct lp55xx_device_config *cfg = chip->cfg;
497         int ret;
498
499         if (!cfg->run_engine || !cfg->firmware_cb)
500                 goto dev_specific_attrs;
501
502         ret = sysfs_create_group(&dev->kobj, &lp55xx_engine_attr_group);
503         if (ret)
504                 return ret;
505
506 dev_specific_attrs:
507         return cfg->dev_attr_group ?
508                 sysfs_create_group(&dev->kobj, cfg->dev_attr_group) : 0;
509 }
510 EXPORT_SYMBOL_GPL(lp55xx_register_sysfs);
511
512 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
513 MODULE_DESCRIPTION("LP55xx Common Driver");
514 MODULE_LICENSE("GPL");