1 /*
2 * Simple driver for Texas Instruments LM3642 LED Flash 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/delay.h>
12 #include <linux/i2c.h>
13 #include <linux/leds.h>
14 #include <linux/slab.h>
15 #include <linux/platform_device.h>
16 #include <linux/fs.h>
17 #include <linux/regmap.h>
18 #include <linux/workqueue.h>
19 #include <linux/platform_data/leds-lm3642.h>
20
21 #define REG_FILT_TIME (0x0)
22 #define REG_IVFM_MODE (0x1)
23 #define REG_TORCH_TIME (0x6)
24 #define REG_FLASH (0x8)
25 #define REG_I_CTRL (0x9)
26 #define REG_ENABLE (0xA)
27 #define REG_FLAG (0xB)
28 #define REG_MAX (0xB)
29
30 #define UVLO_EN_SHIFT (7)
31 #define IVM_D_TH_SHIFT (2)
32 #define TORCH_RAMP_UP_TIME_SHIFT (3)
33 #define TORCH_RAMP_DN_TIME_SHIFT (0)
34 #define INDUCTOR_I_LIMIT_SHIFT (6)
35 #define FLASH_RAMP_TIME_SHIFT (3)
36 #define FLASH_TOUT_TIME_SHIFT (0)
37 #define TORCH_I_SHIFT (4)
38 #define FLASH_I_SHIFT (0)
39 #define IVFM_SHIFT (7)
40 #define TX_PIN_EN_SHIFT (6)
41 #define STROBE_PIN_EN_SHIFT (5)
42 #define TORCH_PIN_EN_SHIFT (4)
43 #define MODE_BITS_SHIFT (0)
44
45 #define UVLO_EN_MASK (0x1)
46 #define IVM_D_TH_MASK (0x7)
47 #define TORCH_RAMP_UP_TIME_MASK (0x7)
48 #define TORCH_RAMP_DN_TIME_MASK (0x7)
49 #define INDUCTOR_I_LIMIT_MASK (0x1)
50 #define FLASH_RAMP_TIME_MASK (0x7)
51 #define FLASH_TOUT_TIME_MASK (0x7)
52 #define TORCH_I_MASK (0x7)
53 #define FLASH_I_MASK (0xF)
54 #define IVFM_MASK (0x1)
55 #define TX_PIN_EN_MASK (0x1)
56 #define STROBE_PIN_EN_MASK (0x1)
57 #define TORCH_PIN_EN_MASK (0x1)
58 #define MODE_BITS_MASK (0x73)
59 #define EX_PIN_CONTROL_MASK (0x71)
60 #define EX_PIN_ENABLE_MASK (0x70)
61
62 enum lm3642_mode {
63 MODES_STASNDBY = 0,
64 MODES_INDIC,
65 MODES_TORCH,
66 MODES_FLASH
67 };
68
69 struct lm3642_chip_data {
70 struct device *dev;
71
72 struct led_classdev cdev_flash;
73 struct led_classdev cdev_torch;
74 struct led_classdev cdev_indicator;
75
76 struct work_struct work_flash;
77 struct work_struct work_torch;
78 struct work_struct work_indicator;
79
80 u8 br_flash;
81 u8 br_torch;
82 u8 br_indicator;
83
84 enum lm3642_torch_pin_enable torch_pin;
85 enum lm3642_strobe_pin_enable strobe_pin;
86 enum lm3642_tx_pin_enable tx_pin;
87
88 struct lm3642_platform_data *pdata;
89 struct regmap *regmap;
90 struct mutex lock;
91
92 unsigned int last_flag;
93 };
94
95 /* chip initialize */
lm3642_chip_init(struct lm3642_chip_data * chip)96 static int lm3642_chip_init(struct lm3642_chip_data *chip)
97 {
98 int ret;
99 struct lm3642_platform_data *pdata = chip->pdata;
100
101 /* set enable register */
102 ret = regmap_update_bits(chip->regmap, REG_ENABLE, EX_PIN_ENABLE_MASK,
103 pdata->tx_pin);
104 if (ret < 0)
105 dev_err(chip->dev, "Failed to update REG_ENABLE Register\n");
106 return ret;
107 }
108
109 /* chip control */
lm3642_control(struct lm3642_chip_data * chip,u8 brightness,enum lm3642_mode opmode)110 static int lm3642_control(struct lm3642_chip_data *chip,
111 u8 brightness, enum lm3642_mode opmode)
112 {
113 int ret;
114
115 ret = regmap_read(chip->regmap, REG_FLAG, &chip->last_flag);
116 if (ret < 0) {
117 dev_err(chip->dev, "Failed to read REG_FLAG Register\n");
118 goto out;
119 }
120
121 if (chip->last_flag)
122 dev_info(chip->dev, "Last FLAG is 0x%x\n", chip->last_flag);
123
124 /* brightness 0 means off-state */
125 if (!brightness)
126 opmode = MODES_STASNDBY;
127
128 switch (opmode) {
129 case MODES_TORCH:
130 ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
131 TORCH_I_MASK << TORCH_I_SHIFT,
132 (brightness - 1) << TORCH_I_SHIFT);
133
134 if (chip->torch_pin)
135 opmode |= (TORCH_PIN_EN_MASK << TORCH_PIN_EN_SHIFT);
136 break;
137
138 case MODES_FLASH:
139 ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
140 FLASH_I_MASK << FLASH_I_SHIFT,
141 (brightness - 1) << FLASH_I_SHIFT);
142
143 if (chip->strobe_pin)
144 opmode |= (STROBE_PIN_EN_MASK << STROBE_PIN_EN_SHIFT);
145 break;
146
147 case MODES_INDIC:
148 ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
149 TORCH_I_MASK << TORCH_I_SHIFT,
150 (brightness - 1) << TORCH_I_SHIFT);
151 break;
152
153 case MODES_STASNDBY:
154
155 break;
156
157 default:
158 return ret;
159 }
160 if (ret < 0) {
161 dev_err(chip->dev, "Failed to write REG_I_CTRL Register\n");
162 goto out;
163 }
164
165 if (chip->tx_pin)
166 opmode |= (TX_PIN_EN_MASK << TX_PIN_EN_SHIFT);
167
168 ret = regmap_update_bits(chip->regmap, REG_ENABLE,
169 MODE_BITS_MASK << MODE_BITS_SHIFT,
170 opmode << MODE_BITS_SHIFT);
171 out:
172 return ret;
173 }
174
175 /* torch */
176
177 /* torch pin config for lm3642*/
lm3642_torch_pin_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)178 static ssize_t lm3642_torch_pin_store(struct device *dev,
179 struct device_attribute *attr,
180 const char *buf, size_t size)
181 {
182 ssize_t ret;
183 struct led_classdev *led_cdev = dev_get_drvdata(dev);
184 struct lm3642_chip_data *chip =
185 container_of(led_cdev, struct lm3642_chip_data, cdev_indicator);
186 unsigned int state;
187
188 ret = kstrtouint(buf, 10, &state);
189 if (ret)
190 goto out_strtoint;
191 if (state != 0)
192 state = 0x01 << TORCH_PIN_EN_SHIFT;
193
194 chip->torch_pin = state;
195 ret = regmap_update_bits(chip->regmap, REG_ENABLE,
196 TORCH_PIN_EN_MASK << TORCH_PIN_EN_SHIFT,
197 state);
198 if (ret < 0)
199 goto out;
200
201 return size;
202 out:
203 dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
204 return ret;
205 out_strtoint:
206 dev_err(chip->dev, "%s: fail to change str to int\n", __func__);
207 return ret;
208 }
209
210 static DEVICE_ATTR(torch_pin, S_IWUSR, NULL, lm3642_torch_pin_store);
211
lm3642_deferred_torch_brightness_set(struct work_struct * work)212 static void lm3642_deferred_torch_brightness_set(struct work_struct *work)
213 {
214 struct lm3642_chip_data *chip =
215 container_of(work, struct lm3642_chip_data, work_torch);
216
217 mutex_lock(&chip->lock);
218 lm3642_control(chip, chip->br_torch, MODES_TORCH);
219 mutex_unlock(&chip->lock);
220 }
221
lm3642_torch_brightness_set(struct led_classdev * cdev,enum led_brightness brightness)222 static void lm3642_torch_brightness_set(struct led_classdev *cdev,
223 enum led_brightness brightness)
224 {
225 struct lm3642_chip_data *chip =
226 container_of(cdev, struct lm3642_chip_data, cdev_torch);
227
228 chip->br_torch = brightness;
229 schedule_work(&chip->work_torch);
230 }
231
232 /* flash */
233
234 /* strobe pin config for lm3642*/
lm3642_strobe_pin_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)235 static ssize_t lm3642_strobe_pin_store(struct device *dev,
236 struct device_attribute *attr,
237 const char *buf, size_t size)
238 {
239 ssize_t ret;
240 struct led_classdev *led_cdev = dev_get_drvdata(dev);
241 struct lm3642_chip_data *chip =
242 container_of(led_cdev, struct lm3642_chip_data, cdev_indicator);
243 unsigned int state;
244
245 ret = kstrtouint(buf, 10, &state);
246 if (ret)
247 goto out_strtoint;
248 if (state != 0)
249 state = 0x01 << STROBE_PIN_EN_SHIFT;
250
251 chip->strobe_pin = state;
252 ret = regmap_update_bits(chip->regmap, REG_ENABLE,
253 STROBE_PIN_EN_MASK << STROBE_PIN_EN_SHIFT,
254 state);
255 if (ret < 0)
256 goto out;
257
258 return size;
259 out:
260 dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
261 return ret;
262 out_strtoint:
263 dev_err(chip->dev, "%s: fail to change str to int\n", __func__);
264 return ret;
265 }
266
267 static DEVICE_ATTR(strobe_pin, S_IWUSR, NULL, lm3642_strobe_pin_store);
268
lm3642_deferred_strobe_brightness_set(struct work_struct * work)269 static void lm3642_deferred_strobe_brightness_set(struct work_struct *work)
270 {
271 struct lm3642_chip_data *chip =
272 container_of(work, struct lm3642_chip_data, work_flash);
273
274 mutex_lock(&chip->lock);
275 lm3642_control(chip, chip->br_flash, MODES_FLASH);
276 mutex_unlock(&chip->lock);
277 }
278
lm3642_strobe_brightness_set(struct led_classdev * cdev,enum led_brightness brightness)279 static void lm3642_strobe_brightness_set(struct led_classdev *cdev,
280 enum led_brightness brightness)
281 {
282 struct lm3642_chip_data *chip =
283 container_of(cdev, struct lm3642_chip_data, cdev_flash);
284
285 chip->br_flash = brightness;
286 schedule_work(&chip->work_flash);
287 }
288
289 /* indicator */
lm3642_deferred_indicator_brightness_set(struct work_struct * work)290 static void lm3642_deferred_indicator_brightness_set(struct work_struct *work)
291 {
292 struct lm3642_chip_data *chip =
293 container_of(work, struct lm3642_chip_data, work_indicator);
294
295 mutex_lock(&chip->lock);
296 lm3642_control(chip, chip->br_indicator, MODES_INDIC);
297 mutex_unlock(&chip->lock);
298 }
299
lm3642_indicator_brightness_set(struct led_classdev * cdev,enum led_brightness brightness)300 static void lm3642_indicator_brightness_set(struct led_classdev *cdev,
301 enum led_brightness brightness)
302 {
303 struct lm3642_chip_data *chip =
304 container_of(cdev, struct lm3642_chip_data, cdev_indicator);
305
306 chip->br_indicator = brightness;
307 schedule_work(&chip->work_indicator);
308 }
309
310 static const struct regmap_config lm3642_regmap = {
311 .reg_bits = 8,
312 .val_bits = 8,
313 .max_register = REG_MAX,
314 };
315
lm3642_probe(struct i2c_client * client,const struct i2c_device_id * id)316 static int lm3642_probe(struct i2c_client *client,
317 const struct i2c_device_id *id)
318 {
319 struct lm3642_platform_data *pdata = client->dev.platform_data;
320 struct lm3642_chip_data *chip;
321
322 int err;
323
324 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
325 dev_err(&client->dev, "i2c functionality check fail.\n");
326 return -EOPNOTSUPP;
327 }
328
329 if (pdata == NULL) {
330 dev_err(&client->dev, "needs Platform Data.\n");
331 return -ENODATA;
332 }
333
334 chip = devm_kzalloc(&client->dev,
335 sizeof(struct lm3642_chip_data), GFP_KERNEL);
336 if (!chip)
337 return -ENOMEM;
338
339 chip->dev = &client->dev;
340 chip->pdata = pdata;
341
342 chip->tx_pin = pdata->tx_pin;
343 chip->torch_pin = pdata->torch_pin;
344 chip->strobe_pin = pdata->strobe_pin;
345
346 chip->regmap = devm_regmap_init_i2c(client, &lm3642_regmap);
347 if (IS_ERR(chip->regmap)) {
348 err = PTR_ERR(chip->regmap);
349 dev_err(&client->dev, "Failed to allocate register map: %d\n",
350 err);
351 return err;
352 }
353
354 mutex_init(&chip->lock);
355 i2c_set_clientdata(client, chip);
356
357 err = lm3642_chip_init(chip);
358 if (err < 0)
359 goto err_out;
360
361 /* flash */
362 INIT_WORK(&chip->work_flash, lm3642_deferred_strobe_brightness_set);
363 chip->cdev_flash.name = "flash";
364 chip->cdev_flash.max_brightness = 16;
365 chip->cdev_flash.brightness_set = lm3642_strobe_brightness_set;
366 chip->cdev_flash.default_trigger = "flash";
367 err = led_classdev_register((struct device *)
368 &client->dev, &chip->cdev_flash);
369 if (err < 0) {
370 dev_err(chip->dev, "failed to register flash\n");
371 goto err_out;
372 }
373 err = device_create_file(chip->cdev_flash.dev, &dev_attr_strobe_pin);
374 if (err < 0) {
375 dev_err(chip->dev, "failed to create strobe-pin file\n");
376 goto err_create_flash_pin_file;
377 }
378
379 /* torch */
380 INIT_WORK(&chip->work_torch, lm3642_deferred_torch_brightness_set);
381 chip->cdev_torch.name = "torch";
382 chip->cdev_torch.max_brightness = 8;
383 chip->cdev_torch.brightness_set = lm3642_torch_brightness_set;
384 chip->cdev_torch.default_trigger = "torch";
385 err = led_classdev_register((struct device *)
386 &client->dev, &chip->cdev_torch);
387 if (err < 0) {
388 dev_err(chip->dev, "failed to register torch\n");
389 goto err_create_torch_file;
390 }
391 err = device_create_file(chip->cdev_torch.dev, &dev_attr_torch_pin);
392 if (err < 0) {
393 dev_err(chip->dev, "failed to create torch-pin file\n");
394 goto err_create_torch_pin_file;
395 }
396
397 /* indicator */
398 INIT_WORK(&chip->work_indicator,
399 lm3642_deferred_indicator_brightness_set);
400 chip->cdev_indicator.name = "indicator";
401 chip->cdev_indicator.max_brightness = 8;
402 chip->cdev_indicator.brightness_set = lm3642_indicator_brightness_set;
403 err = led_classdev_register((struct device *)
404 &client->dev, &chip->cdev_indicator);
405 if (err < 0) {
406 dev_err(chip->dev, "failed to register indicator\n");
407 goto err_create_indicator_file;
408 }
409
410 dev_info(&client->dev, "LM3642 is initialized\n");
411 return 0;
412
413 err_create_indicator_file:
414 device_remove_file(chip->cdev_torch.dev, &dev_attr_torch_pin);
415 err_create_torch_pin_file:
416 led_classdev_unregister(&chip->cdev_torch);
417 err_create_torch_file:
418 device_remove_file(chip->cdev_flash.dev, &dev_attr_strobe_pin);
419 err_create_flash_pin_file:
420 led_classdev_unregister(&chip->cdev_flash);
421 err_out:
422 return err;
423 }
424
lm3642_remove(struct i2c_client * client)425 static int lm3642_remove(struct i2c_client *client)
426 {
427 struct lm3642_chip_data *chip = i2c_get_clientdata(client);
428
429 led_classdev_unregister(&chip->cdev_indicator);
430 flush_work(&chip->work_indicator);
431 device_remove_file(chip->cdev_torch.dev, &dev_attr_torch_pin);
432 led_classdev_unregister(&chip->cdev_torch);
433 flush_work(&chip->work_torch);
434 device_remove_file(chip->cdev_flash.dev, &dev_attr_strobe_pin);
435 led_classdev_unregister(&chip->cdev_flash);
436 flush_work(&chip->work_flash);
437 regmap_write(chip->regmap, REG_ENABLE, 0);
438 return 0;
439 }
440
441 static const struct i2c_device_id lm3642_id[] = {
442 {LM3642_NAME, 0},
443 {}
444 };
445
446 MODULE_DEVICE_TABLE(i2c, lm3642_id);
447
448 static struct i2c_driver lm3642_i2c_driver = {
449 .driver = {
450 .name = LM3642_NAME,
451 .owner = THIS_MODULE,
452 .pm = NULL,
453 },
454 .probe = lm3642_probe,
455 .remove = lm3642_remove,
456 .id_table = lm3642_id,
457 };
458
459 module_i2c_driver(lm3642_i2c_driver);
460
461 MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM3642");
462 MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
463 MODULE_AUTHOR("G.Shark Jeong <gshark.jeong@gmail.com>");
464 MODULE_LICENSE("GPL v2");
465