1
2
3
4
5
6
7
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>
21
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
35
36#define INT_DEBOUNCE_MSEC 10
37struct lm3630a_chip {
38 struct device *dev;
39 struct delayed_work work;
40
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};
49
50
51static int lm3630a_read(struct lm3630a_chip *pchip, unsigned int reg)
52{
53 int rval;
54 unsigned int reg_val;
55
56 rval = regmap_read(pchip->regmap, reg, ®_val);
57 if (rval < 0)
58 return rval;
59 return reg_val & 0xFF;
60}
61
62static int lm3630a_write(struct lm3630a_chip *pchip,
63 unsigned int reg, unsigned int data)
64{
65 return regmap_write(pchip->regmap, reg, data);
66}
67
68static 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}
74
75
76static int lm3630a_chip_init(struct lm3630a_chip *pchip)
77{
78 int rval;
79 struct lm3630a_platform_data *pdata = pchip->pdata;
80
81 usleep_range(1000, 2000);
82
83 rval = lm3630a_write(pchip, 0x50, 0x03);
84
85 rval |= lm3630a_update(pchip, REG_CONFIG, 0x07, pdata->pwm_ctrl);
86
87 rval |= lm3630a_write(pchip, REG_BOOST, 0x38);
88
89 rval |= lm3630a_update(pchip, REG_I_A, 0x1F, 0x1F);
90
91 rval |= lm3630a_write(pchip, REG_I_B, 0x1F);
92
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
97 rval |= lm3630a_write(pchip, REG_BRT_A, pdata->leda_init_brt);
98 rval |= lm3630a_write(pchip, REG_BRT_B, pdata->ledb_init_brt);
99
100 if (rval < 0)
101 dev_err(pchip->dev, "i2c failed to access register\n");
102 return rval;
103}
104
105
106static void lm3630a_delayed_func(struct work_struct *work)
107{
108 int rval;
109 struct lm3630a_chip *pchip;
110
111 pchip = container_of(work, struct lm3630a_chip, work.work);
112
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 }
119
120 dev_info(pchip->dev, "REG_INT_STATUS Register is 0x%x\n", rval);
121}
122
123static irqreturn_t lm3630a_isr_func(int irq, void *chip)
124{
125 int rval;
126 struct lm3630a_chip *pchip = chip;
127 unsigned long delay = msecs_to_jiffies(INT_DEBOUNCE_MSEC);
128
129 queue_delayed_work(pchip->irqthread, &pchip->work, delay);
130
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;
137}
138
139static int lm3630a_intr_config(struct lm3630a_chip *pchip)
140{
141 int rval;
142
143 rval = lm3630a_write(pchip, REG_INT_EN, 0x87);
144 if (rval < 0)
145 return rval;
146
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;
161}
162
163static void lm3630a_pwm_ctrl(struct lm3630a_chip *pchip, int br, int br_max)
164{
165 unsigned int period = pwm_get_period(pchip->pwmd);
166 unsigned int duty = br * period / br_max;
167
168 pwm_config(pchip->pwmd, duty, period);
169 if (duty)
170 pwm_enable(pchip->pwmd);
171 else
172 pwm_disable(pchip->pwmd);
173}
174
175
176static int lm3630a_bank_a_update_status(struct backlight_device *bl)
177{
178 int ret;
179 struct lm3630a_chip *pchip = bl_get_data(bl);
180 enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
181
182
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 }
188
189
190 ret = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
191 if (ret < 0)
192 goto out_i2c_err;
193 usleep_range(1000, 2000);
194
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;
204
205out_i2c_err:
206 dev_err(pchip->dev, "i2c failed to access\n");
207 return bl->props.brightness;
208}
209
210static int lm3630a_bank_a_get_brightness(struct backlight_device *bl)
211{
212 int brightness, rval;
213 struct lm3630a_chip *pchip = bl_get_data(bl);
214 enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
215
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 }
227
228
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;
237
238out:
239 bl->props.brightness = brightness;
240 return bl->props.brightness;
241out_i2c_err:
242 dev_err(pchip->dev, "i2c failed to access register\n");
243 return 0;
244}
245
246static 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};
251
252
253static int lm3630a_bank_b_update_status(struct backlight_device *bl)
254{
255 int ret;
256 struct lm3630a_chip *pchip = bl_get_data(bl);
257 enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
258
259
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 }
265
266
267 ret = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
268 if (ret < 0)
269 goto out_i2c_err;
270 usleep_range(1000, 2000);
271
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;
281
282out_i2c_err:
283 dev_err(pchip->dev, "i2c failed to access REG_CTRL\n");
284 return bl->props.brightness;
285}
286
287static int lm3630a_bank_b_get_brightness(struct backlight_device *bl)
288{
289 int brightness, rval;
290 struct lm3630a_chip *pchip = bl_get_data(bl);
291 enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
292
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 }
304
305
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;
314
315out:
316 bl->props.brightness = brightness;
317 return bl->props.brightness;
318out_i2c_err:
319 dev_err(pchip->dev, "i2c failed to access register\n");
320 return 0;
321}
322
323static 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};
328
329static int lm3630a_backlight_register(struct lm3630a_chip *pchip)
330{
331 struct backlight_properties props;
332 struct lm3630a_platform_data *pdata = pchip->pdata;
333
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 }
345
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;
358}
359
360static const struct regmap_config lm3630a_regmap = {
361 .reg_bits = 8,
362 .val_bits = 8,
363 .max_register = REG_MAX,
364};
365
366static int lm3630a_probe(struct i2c_client *client,
367 const struct i2c_device_id *id)
368{
369 struct lm3630a_platform_data *pdata = dev_get_platdata(&client->dev);
370 struct lm3630a_chip *pchip;
371 int rval;
372
373 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
374 dev_err(&client->dev, "fail : i2c functionality check\n");
375 return -EOPNOTSUPP;
376 }
377
378 pchip = devm_kzalloc(&client->dev, sizeof(struct lm3630a_chip),
379 GFP_KERNEL);
380 if (!pchip)
381 return -ENOMEM;
382 pchip->dev = &client->dev;
383
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 }
390
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
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;
407
408
409 rval = lm3630a_chip_init(pchip);
410 if (rval < 0) {
411 dev_err(&client->dev, "fail : init chip\n");
412 return rval;
413 }
414
415 rval = lm3630a_backlight_register(pchip);
416 if (rval < 0) {
417 dev_err(&client->dev, "fail : backlight register.\n");
418 return rval;
419 }
420
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;
429
430
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;
439}
440
441static int lm3630a_remove(struct i2c_client *client)
442{
443 int rval;
444 struct lm3630a_chip *pchip = i2c_get_clientdata(client);
445
446 rval = lm3630a_write(pchip, REG_BRT_A, 0);
447 if (rval < 0)
448 dev_err(pchip->dev, "i2c failed to access register\n");
449
450 rval = lm3630a_write(pchip, REG_BRT_B, 0);
451 if (rval < 0)
452 dev_err(pchip->dev, "i2c failed to access register\n");
453
454 if (pchip->irq) {
455 free_irq(pchip->irq, pchip);
456 flush_workqueue(pchip->irqthread);
457 destroy_workqueue(pchip->irqthread);
458 }
459 return 0;
460}
461
462static const struct i2c_device_id lm3630a_id[] = {
463 {LM3630A_NAME, 0},
464 {}
465};
466
467MODULE_DEVICE_TABLE(i2c, lm3630a_id);
468
469static 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};
477
478module_i2c_driver(lm3630a_i2c_driver);
479
480MODULE_DESCRIPTION("Texas Instruments Backlight driver for LM3630A");
481MODULE_AUTHOR("Daniel Jeong <gshark.jeong@gmail.com>");
482MODULE_AUTHOR("LDD MLP <ldd-mlp@list.ti.com>");
483MODULE_LICENSE("GPL v2");
484
