LP8758 - consolidated version
[mlp-open-source/kernel.git] / drivers / video / backlight / lm3630a_bl.c
1 /*
2 * Simple driver for Texas Instruments LM3630A Backlight driver chip
3 * Copyright (C) 2012 Texas Instruments
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 version 2 as
7 * published by the Free Software Foundation.
8 *
9 */
10 #include <linux/module.h>
11 #include <linux/slab.h>
12 #include <linux/i2c.h>
13 #include <linux/backlight.h>
14 #include <linux/err.h>
15 #include <linux/delay.h>
16 #include <linux/uaccess.h>
17 #include <linux/interrupt.h>
18 #include <linux/regmap.h>
19 #include <linux/pwm.h>
20 #include <linux/platform_data/lm3630a_bl.h>
22 #define REG_CTRL        0x00
23 #define REG_BOOST       0x02
24 #define REG_CONFIG      0x01
25 #define REG_BRT_A       0x03
26 #define REG_BRT_B       0x04
27 #define REG_I_A         0x05
28 #define REG_I_B         0x06
29 #define REG_INT_STATUS  0x09
30 #define REG_INT_EN      0x0A
31 #define REG_FAULT       0x0B
32 #define REG_PWM_OUTLOW  0x12
33 #define REG_PWM_OUTHIGH 0x13
34 #define REG_MAX         0x1F
36 #define INT_DEBOUNCE_MSEC       10
37 struct lm3630a_chip {
38         struct device *dev;
39         struct delayed_work work;
41         int irq;
42         struct workqueue_struct *irqthread;
43         struct lm3630a_platform_data *pdata;
44         struct backlight_device *bleda;
45         struct backlight_device *bledb;
46         struct regmap *regmap;
47         struct pwm_device *pwmd;
48 };
50 /* i2c access */
51 static int lm3630a_read(struct lm3630a_chip *pchip, unsigned int reg)
52 {
53         int rval;
54         unsigned int reg_val;
56         rval = regmap_read(pchip->regmap, reg, &reg_val);
57         if (rval < 0)
58                 return rval;
59         return reg_val & 0xFF;
60 }
62 static int lm3630a_write(struct lm3630a_chip *pchip,
63                          unsigned int reg, unsigned int data)
64 {
65         return regmap_write(pchip->regmap, reg, data);
66 }
68 static int lm3630a_update(struct lm3630a_chip *pchip,
69                           unsigned int reg, unsigned int mask,
70                           unsigned int data)
71 {
72         return regmap_update_bits(pchip->regmap, reg, mask, data);
73 }
75 /* initialize chip */
76 static int lm3630a_chip_init(struct lm3630a_chip *pchip)
77 {
78         int rval;
79         struct lm3630a_platform_data *pdata = pchip->pdata;
81         usleep_range(1000, 2000);
82         /* set Filter Strength Register */
83         rval = lm3630a_write(pchip, 0x50, 0x03);
84         /* set Cofig. register */
85         rval |= lm3630a_update(pchip, REG_CONFIG, 0x07, pdata->pwm_ctrl);
86         /* set boost control */
87         rval |= lm3630a_write(pchip, REG_BOOST, 0x38);
88         /* set current A */
89         rval |= lm3630a_update(pchip, REG_I_A, 0x1F, 0x1F);
90         /* set current B */
91         rval |= lm3630a_write(pchip, REG_I_B, 0x1F);
92         /* set control */
93         rval |= lm3630a_update(pchip, REG_CTRL, 0x14, pdata->leda_ctrl);
94         rval |= lm3630a_update(pchip, REG_CTRL, 0x0B, pdata->ledb_ctrl);
95         usleep_range(1000, 2000);
96         /* set brightness A and B */
97         rval |= lm3630a_write(pchip, REG_BRT_A, pdata->leda_init_brt);
98         rval |= lm3630a_write(pchip, REG_BRT_B, pdata->ledb_init_brt);
100         if (rval < 0)
101                 dev_err(pchip->dev, "i2c failed to access register\n");
102         return rval;
105 /* interrupt handling */
106 static void lm3630a_delayed_func(struct work_struct *work)
108         int rval;
109         struct lm3630a_chip *pchip;
111         pchip = container_of(work, struct lm3630a_chip, work.work);
113         rval = lm3630a_read(pchip, REG_INT_STATUS);
114         if (rval < 0) {
115                 dev_err(pchip->dev,
116                         "i2c failed to access REG_INT_STATUS Register\n");
117                 return;
118         }
120         dev_info(pchip->dev, "REG_INT_STATUS Register is 0x%x\n", rval);
123 static irqreturn_t lm3630a_isr_func(int irq, void *chip)
125         int rval;
126         struct lm3630a_chip *pchip = chip;
127         unsigned long delay = msecs_to_jiffies(INT_DEBOUNCE_MSEC);
129         queue_delayed_work(pchip->irqthread, &pchip->work, delay);
131         rval = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
132         if (rval < 0) {
133                 dev_err(pchip->dev, "i2c failed to access register\n");
134                 return IRQ_NONE;
135         }
136         return IRQ_HANDLED;
139 static int lm3630a_intr_config(struct lm3630a_chip *pchip)
141         int rval;
143         rval = lm3630a_write(pchip, REG_INT_EN, 0x87);
144         if (rval < 0)
145                 return rval;
147         INIT_DELAYED_WORK(&pchip->work, lm3630a_delayed_func);
148         pchip->irqthread = create_singlethread_workqueue("lm3630a-irqthd");
149         if (!pchip->irqthread) {
150                 dev_err(pchip->dev, "create irq thread fail\n");
151                 return -ENOMEM;
152         }
153         if (request_threaded_irq
154             (pchip->irq, NULL, lm3630a_isr_func,
155              IRQF_TRIGGER_FALLING | IRQF_ONESHOT, "lm3630a_irq", pchip)) {
156                 dev_err(pchip->dev, "request threaded irq fail\n");
157                 destroy_workqueue(pchip->irqthread);
158                 return -ENOMEM;
159         }
160         return rval;
163 static void lm3630a_pwm_ctrl(struct lm3630a_chip *pchip, int br, int br_max)
165         unsigned int period = pwm_get_period(pchip->pwmd);
166         unsigned int duty = br * period / br_max;
168         pwm_config(pchip->pwmd, duty, period);
169         if (duty)
170                 pwm_enable(pchip->pwmd);
171         else
172                 pwm_disable(pchip->pwmd);
175 /* update and get brightness */
176 static int lm3630a_bank_a_update_status(struct backlight_device *bl)
178         int ret;
179         struct lm3630a_chip *pchip = bl_get_data(bl);
180         enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
182         /* pwm control */
183         if ((pwm_ctrl & LM3630A_PWM_BANK_A) != 0) {
184                 lm3630a_pwm_ctrl(pchip, bl->props.brightness,
185                                  bl->props.max_brightness);
186                 return bl->props.brightness;
187         }
189         /* disable sleep */
190         ret = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
191         if (ret < 0)
192                 goto out_i2c_err;
193         usleep_range(1000, 2000);
194         /* minimum brightness is 0x04 */
195         ret = lm3630a_write(pchip, REG_BRT_A, bl->props.brightness);
196         if (bl->props.brightness < 0x4)
197                 ret |= lm3630a_update(pchip, REG_CTRL, LM3630A_LEDA_ENABLE, 0);
198         else
199                 ret |= lm3630a_update(pchip, REG_CTRL,
200                                       LM3630A_LEDA_ENABLE, LM3630A_LEDA_ENABLE);
201         if (ret < 0)
202                 goto out_i2c_err;
203         return bl->props.brightness;
205 out_i2c_err:
206         dev_err(pchip->dev, "i2c failed to access\n");
207         return bl->props.brightness;
210 static int lm3630a_bank_a_get_brightness(struct backlight_device *bl)
212         int brightness, rval;
213         struct lm3630a_chip *pchip = bl_get_data(bl);
214         enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
216         if ((pwm_ctrl & LM3630A_PWM_BANK_A) != 0) {
217                 rval = lm3630a_read(pchip, REG_PWM_OUTHIGH);
218                 if (rval < 0)
219                         goto out_i2c_err;
220                 brightness = (rval & 0x01) << 8;
221                 rval = lm3630a_read(pchip, REG_PWM_OUTLOW);
222                 if (rval < 0)
223                         goto out_i2c_err;
224                 brightness |= rval;
225                 goto out;
226         }
228         /* disable sleep */
229         rval = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
230         if (rval < 0)
231                 goto out_i2c_err;
232         usleep_range(1000, 2000);
233         rval = lm3630a_read(pchip, REG_BRT_A);
234         if (rval < 0)
235                 goto out_i2c_err;
236         brightness = rval;
238 out:
239         bl->props.brightness = brightness;
240         return bl->props.brightness;
241 out_i2c_err:
242         dev_err(pchip->dev, "i2c failed to access register\n");
243         return 0;
246 static const struct backlight_ops lm3630a_bank_a_ops = {
247         .options = BL_CORE_SUSPENDRESUME,
248         .update_status = lm3630a_bank_a_update_status,
249         .get_brightness = lm3630a_bank_a_get_brightness,
250 };
252 /* update and get brightness */
253 static int lm3630a_bank_b_update_status(struct backlight_device *bl)
255         int ret;
256         struct lm3630a_chip *pchip = bl_get_data(bl);
257         enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
259         /* pwm control */
260         if ((pwm_ctrl & LM3630A_PWM_BANK_B) != 0) {
261                 lm3630a_pwm_ctrl(pchip, bl->props.brightness,
262                                  bl->props.max_brightness);
263                 return bl->props.brightness;
264         }
266         /* disable sleep */
267         ret = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
268         if (ret < 0)
269                 goto out_i2c_err;
270         usleep_range(1000, 2000);
271         /* minimum brightness is 0x04 */
272         ret = lm3630a_write(pchip, REG_BRT_B, bl->props.brightness);
273         if (bl->props.brightness < 0x4)
274                 ret |= lm3630a_update(pchip, REG_CTRL, LM3630A_LEDB_ENABLE, 0);
275         else
276                 ret |= lm3630a_update(pchip, REG_CTRL,
277                                       LM3630A_LEDB_ENABLE, LM3630A_LEDB_ENABLE);
278         if (ret < 0)
279                 goto out_i2c_err;
280         return bl->props.brightness;
282 out_i2c_err:
283         dev_err(pchip->dev, "i2c failed to access REG_CTRL\n");
284         return bl->props.brightness;
287 static int lm3630a_bank_b_get_brightness(struct backlight_device *bl)
289         int brightness, rval;
290         struct lm3630a_chip *pchip = bl_get_data(bl);
291         enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
293         if ((pwm_ctrl & LM3630A_PWM_BANK_B) != 0) {
294                 rval = lm3630a_read(pchip, REG_PWM_OUTHIGH);
295                 if (rval < 0)
296                         goto out_i2c_err;
297                 brightness = (rval & 0x01) << 8;
298                 rval = lm3630a_read(pchip, REG_PWM_OUTLOW);
299                 if (rval < 0)
300                         goto out_i2c_err;
301                 brightness |= rval;
302                 goto out;
303         }
305         /* disable sleep */
306         rval = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
307         if (rval < 0)
308                 goto out_i2c_err;
309         usleep_range(1000, 2000);
310         rval = lm3630a_read(pchip, REG_BRT_B);
311         if (rval < 0)
312                 goto out_i2c_err;
313         brightness = rval;
315 out:
316         bl->props.brightness = brightness;
317         return bl->props.brightness;
318 out_i2c_err:
319         dev_err(pchip->dev, "i2c failed to access register\n");
320         return 0;
323 static const struct backlight_ops lm3630a_bank_b_ops = {
324         .options = BL_CORE_SUSPENDRESUME,
325         .update_status = lm3630a_bank_b_update_status,
326         .get_brightness = lm3630a_bank_b_get_brightness,
327 };
329 static int lm3630a_backlight_register(struct lm3630a_chip *pchip)
331         struct backlight_properties props;
332         struct lm3630a_platform_data *pdata = pchip->pdata;
334         props.type = BACKLIGHT_RAW;
335         if (pdata->leda_ctrl != LM3630A_LEDA_DISABLE) {
336                 props.brightness = pdata->leda_init_brt;
337                 props.max_brightness = pdata->leda_max_brt;
338                 pchip->bleda =
339                     devm_backlight_device_register(pchip->dev, "lm3630a_leda",
340                                                    pchip->dev, pchip,
341                                                    &lm3630a_bank_a_ops, &props);
342                 if (IS_ERR(pchip->bleda))
343                         return PTR_ERR(pchip->bleda);
344         }
346         if ((pdata->ledb_ctrl != LM3630A_LEDB_DISABLE) &&
347             (pdata->ledb_ctrl != LM3630A_LEDB_ON_A)) {
348                 props.brightness = pdata->ledb_init_brt;
349                 props.max_brightness = pdata->ledb_max_brt;
350                 pchip->bledb =
351                     devm_backlight_device_register(pchip->dev, "lm3630a_ledb",
352                                                    pchip->dev, pchip,
353                                                    &lm3630a_bank_b_ops, &props);
354                 if (IS_ERR(pchip->bledb))
355                         return PTR_ERR(pchip->bledb);
356         }
357         return 0;
360 static const struct regmap_config lm3630a_regmap = {
361         .reg_bits = 8,
362         .val_bits = 8,
363         .max_register = REG_MAX,
364 };
366 static int lm3630a_probe(struct i2c_client *client,
367                          const struct i2c_device_id *id)
369         struct lm3630a_platform_data *pdata = dev_get_platdata(&client->dev);
370         struct lm3630a_chip *pchip;
371         int rval;
373         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
374                 dev_err(&client->dev, "fail : i2c functionality check\n");
375                 return -EOPNOTSUPP;
376         }
378         pchip = devm_kzalloc(&client->dev, sizeof(struct lm3630a_chip),
379                              GFP_KERNEL);
380         if (!pchip)
381                 return -ENOMEM;
382         pchip->dev = &client->dev;
384         pchip->regmap = devm_regmap_init_i2c(client, &lm3630a_regmap);
385         if (IS_ERR(pchip->regmap)) {
386                 rval = PTR_ERR(pchip->regmap);
387                 dev_err(&client->dev, "fail : allocate reg. map: %d\n", rval);
388                 return rval;
389         }
391         i2c_set_clientdata(client, pchip);
392         if (pdata == NULL) {
393                 pdata = devm_kzalloc(pchip->dev,
394                                      sizeof(struct lm3630a_platform_data),
395                                      GFP_KERNEL);
396                 if (pdata == NULL)
397                         return -ENOMEM;
398                 /* default values */
399                 pdata->leda_ctrl = LM3630A_LEDA_ENABLE;
400                 pdata->ledb_ctrl = LM3630A_LEDB_ENABLE;
401                 pdata->leda_max_brt = LM3630A_MAX_BRIGHTNESS;
402                 pdata->ledb_max_brt = LM3630A_MAX_BRIGHTNESS;
403                 pdata->leda_init_brt = LM3630A_MAX_BRIGHTNESS;
404                 pdata->ledb_init_brt = LM3630A_MAX_BRIGHTNESS;
405         }
406         pchip->pdata = pdata;
408         /* chip initialize */
409         rval = lm3630a_chip_init(pchip);
410         if (rval < 0) {
411                 dev_err(&client->dev, "fail : init chip\n");
412                 return rval;
413         }
414         /* backlight register */
415         rval = lm3630a_backlight_register(pchip);
416         if (rval < 0) {
417                 dev_err(&client->dev, "fail : backlight register.\n");
418                 return rval;
419         }
420         /* pwm */
421         if (pdata->pwm_ctrl != LM3630A_PWM_DISABLE) {
422                 pchip->pwmd = devm_pwm_get(pchip->dev, "lm3630a-pwm");
423                 if (IS_ERR(pchip->pwmd)) {
424                         dev_err(&client->dev, "fail : get pwm device\n");
425                         return PTR_ERR(pchip->pwmd);
426                 }
427         }
428         pchip->pwmd->period = pdata->pwm_period;
430         /* interrupt enable  : irq 0 is not allowed */
431         pchip->irq = client->irq;
432         if (pchip->irq) {
433                 rval = lm3630a_intr_config(pchip);
434                 if (rval < 0)
435                         return rval;
436         }
437         dev_info(&client->dev, "LM3630A backlight register OK.\n");
438         return 0;
441 static int lm3630a_remove(struct i2c_client *client)
443         int rval;
444         struct lm3630a_chip *pchip = i2c_get_clientdata(client);
446         rval = lm3630a_write(pchip, REG_BRT_A, 0);
447         if (rval < 0)
448                 dev_err(pchip->dev, "i2c failed to access register\n");
450         rval = lm3630a_write(pchip, REG_BRT_B, 0);
451         if (rval < 0)
452                 dev_err(pchip->dev, "i2c failed to access register\n");
454         if (pchip->irq) {
455                 free_irq(pchip->irq, pchip);
456                 flush_workqueue(pchip->irqthread);
457                 destroy_workqueue(pchip->irqthread);
458         }
459         return 0;
462 static const struct i2c_device_id lm3630a_id[] = {
463         {LM3630A_NAME, 0},
464         {}
465 };
467 MODULE_DEVICE_TABLE(i2c, lm3630a_id);
469 static struct i2c_driver lm3630a_i2c_driver = {
470         .driver = {
471                    .name = LM3630A_NAME,
472                    },
473         .probe = lm3630a_probe,
474         .remove = lm3630a_remove,
475         .id_table = lm3630a_id,
476 };
478 module_i2c_driver(lm3630a_i2c_driver);
480 MODULE_DESCRIPTION("Texas Instruments Backlight driver for LM3630A");
481 MODULE_AUTHOR("Daniel Jeong <gshark.jeong@gmail.com>");
482 MODULE_AUTHOR("LDD MLP <ldd-mlp@list.ti.com>");
483 MODULE_LICENSE("GPL v2");