1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Simple driver for Texas Instruments LM3642 LED Flash driver chip
4 * Copyright (C) 2012 Texas Instruments
5 */
6 #include <linux/module.h>
7 #include <linux/delay.h>
8 #include <linux/i2c.h>
9 #include <linux/leds.h>
10 #include <linux/slab.h>
11 #include <linux/platform_device.h>
12 #include <linux/fs.h>
13 #include <linux/regmap.h>
14 #include <linux/platform_data/leds-lm3642.h>
15
16 #define REG_FILT_TIME (0x0)
17 #define REG_IVFM_MODE (0x1)
18 #define REG_TORCH_TIME (0x6)
19 #define REG_FLASH (0x8)
20 #define REG_I_CTRL (0x9)
21 #define REG_ENABLE (0xA)
22 #define REG_FLAG (0xB)
23 #define REG_MAX (0xB)
24
25 #define UVLO_EN_SHIFT (7)
26 #define IVM_D_TH_SHIFT (2)
27 #define TORCH_RAMP_UP_TIME_SHIFT (3)
28 #define TORCH_RAMP_DN_TIME_SHIFT (0)
29 #define INDUCTOR_I_LIMIT_SHIFT (6)
30 #define FLASH_RAMP_TIME_SHIFT (3)
31 #define FLASH_TOUT_TIME_SHIFT (0)
32 #define TORCH_I_SHIFT (4)
33 #define FLASH_I_SHIFT (0)
34 #define IVFM_SHIFT (7)
35 #define TX_PIN_EN_SHIFT (6)
36 #define STROBE_PIN_EN_SHIFT (5)
37 #define TORCH_PIN_EN_SHIFT (4)
38 #define MODE_BITS_SHIFT (0)
39
40 #define UVLO_EN_MASK (0x1)
41 #define IVM_D_TH_MASK (0x7)
42 #define TORCH_RAMP_UP_TIME_MASK (0x7)
43 #define TORCH_RAMP_DN_TIME_MASK (0x7)
44 #define INDUCTOR_I_LIMIT_MASK (0x1)
45 #define FLASH_RAMP_TIME_MASK (0x7)
46 #define FLASH_TOUT_TIME_MASK (0x7)
47 #define TORCH_I_MASK (0x7)
48 #define FLASH_I_MASK (0xF)
49 #define IVFM_MASK (0x1)
50 #define TX_PIN_EN_MASK (0x1)
51 #define STROBE_PIN_EN_MASK (0x1)
52 #define TORCH_PIN_EN_MASK (0x1)
53 #define MODE_BITS_MASK (0x73)
54 #define EX_PIN_CONTROL_MASK (0x71)
55 #define EX_PIN_ENABLE_MASK (0x70)
56
57 enum lm3642_mode {
58 MODES_STASNDBY = 0,
59 MODES_INDIC,
60 MODES_TORCH,
61 MODES_FLASH
62 };
63
64 struct lm3642_chip_data {
65 struct device *dev;
66
67 struct led_classdev cdev_flash;
68 struct led_classdev cdev_torch;
69 struct led_classdev cdev_indicator;
70
71 u8 br_flash;
72 u8 br_torch;
73 u8 br_indicator;
74
75 enum lm3642_torch_pin_enable torch_pin;
76 enum lm3642_strobe_pin_enable strobe_pin;
77 enum lm3642_tx_pin_enable tx_pin;
78
79 struct lm3642_platform_data *pdata;
80 struct regmap *regmap;
81 struct mutex lock;
82
83 unsigned int last_flag;
84 };
85
86 /* chip initialize */
lm3642_chip_init(struct lm3642_chip_data * chip)87 static int lm3642_chip_init(struct lm3642_chip_data *chip)
88 {
89 int ret;
90 struct lm3642_platform_data *pdata = chip->pdata;
91
92 /* set enable register */
93 ret = regmap_update_bits(chip->regmap, REG_ENABLE, EX_PIN_ENABLE_MASK,
94 pdata->tx_pin);
95 if (ret < 0)
96 dev_err(chip->dev, "Failed to update REG_ENABLE Register\n");
97 return ret;
98 }
99
100 /* chip control */
lm3642_control(struct lm3642_chip_data * chip,u8 brightness,enum lm3642_mode opmode)101 static int lm3642_control(struct lm3642_chip_data *chip,
102 u8 brightness, enum lm3642_mode opmode)
103 {
104 int ret;
105
106 ret = regmap_read(chip->regmap, REG_FLAG, &chip->last_flag);
107 if (ret < 0) {
108 dev_err(chip->dev, "Failed to read REG_FLAG Register\n");
109 return ret;
110 }
111
112 if (chip->last_flag)
113 dev_info(chip->dev, "Last FLAG is 0x%x\n", chip->last_flag);
114
115 /* brightness 0 means off-state */
116 if (!brightness)
117 opmode = MODES_STASNDBY;
118
119 switch (opmode) {
120 case MODES_TORCH:
121 ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
122 TORCH_I_MASK << TORCH_I_SHIFT,
123 (brightness - 1) << TORCH_I_SHIFT);
124
125 if (chip->torch_pin)
126 opmode |= (TORCH_PIN_EN_MASK << TORCH_PIN_EN_SHIFT);
127 break;
128
129 case MODES_FLASH:
130 ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
131 FLASH_I_MASK << FLASH_I_SHIFT,
132 (brightness - 1) << FLASH_I_SHIFT);
133
134 if (chip->strobe_pin)
135 opmode |= (STROBE_PIN_EN_MASK << STROBE_PIN_EN_SHIFT);
136 break;
137
138 case MODES_INDIC:
139 ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
140 TORCH_I_MASK << TORCH_I_SHIFT,
141 (brightness - 1) << TORCH_I_SHIFT);
142 break;
143
144 case MODES_STASNDBY:
145
146 break;
147
148 default:
149 return -EINVAL;
150 }
151 if (ret < 0) {
152 dev_err(chip->dev, "Failed to write REG_I_CTRL Register\n");
153 return ret;
154 }
155
156 if (chip->tx_pin)
157 opmode |= (TX_PIN_EN_MASK << TX_PIN_EN_SHIFT);
158
159 ret = regmap_update_bits(chip->regmap, REG_ENABLE,
160 MODE_BITS_MASK << MODE_BITS_SHIFT,
161 opmode << MODE_BITS_SHIFT);
162 return ret;
163 }
164
165 /* torch */
166
167 /* torch pin config for lm3642 */
torch_pin_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)168 static ssize_t torch_pin_store(struct device *dev,
169 struct device_attribute *attr,
170 const char *buf, size_t size)
171 {
172 ssize_t ret;
173 struct led_classdev *led_cdev = dev_get_drvdata(dev);
174 struct lm3642_chip_data *chip =
175 container_of(led_cdev, struct lm3642_chip_data, cdev_indicator);
176 unsigned int state;
177
178 ret = kstrtouint(buf, 10, &state);
179 if (ret)
180 return ret;
181 if (state != 0)
182 state = 0x01 << TORCH_PIN_EN_SHIFT;
183
184 chip->torch_pin = state;
185 ret = regmap_update_bits(chip->regmap, REG_ENABLE,
186 TORCH_PIN_EN_MASK << TORCH_PIN_EN_SHIFT,
187 state);
188 if (ret < 0) {
189 dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
190 return ret;
191 }
192
193 return size;
194 }
195
196 static DEVICE_ATTR_WO(torch_pin);
197
lm3642_torch_brightness_set(struct led_classdev * cdev,enum led_brightness brightness)198 static int lm3642_torch_brightness_set(struct led_classdev *cdev,
199 enum led_brightness brightness)
200 {
201 struct lm3642_chip_data *chip =
202 container_of(cdev, struct lm3642_chip_data, cdev_torch);
203 int ret;
204
205 mutex_lock(&chip->lock);
206 chip->br_torch = brightness;
207 ret = lm3642_control(chip, chip->br_torch, MODES_TORCH);
208 mutex_unlock(&chip->lock);
209 return ret;
210 }
211
212 /* flash */
213
214 /* strobe pin config for lm3642*/
strobe_pin_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)215 static ssize_t strobe_pin_store(struct device *dev,
216 struct device_attribute *attr,
217 const char *buf, size_t size)
218 {
219 ssize_t ret;
220 struct led_classdev *led_cdev = dev_get_drvdata(dev);
221 struct lm3642_chip_data *chip =
222 container_of(led_cdev, struct lm3642_chip_data, cdev_indicator);
223 unsigned int state;
224
225 ret = kstrtouint(buf, 10, &state);
226 if (ret)
227 return ret;
228 if (state != 0)
229 state = 0x01 << STROBE_PIN_EN_SHIFT;
230
231 chip->strobe_pin = state;
232 ret = regmap_update_bits(chip->regmap, REG_ENABLE,
233 STROBE_PIN_EN_MASK << STROBE_PIN_EN_SHIFT,
234 state);
235 if (ret < 0) {
236 dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
237 return ret;
238 }
239
240 return size;
241 }
242
243 static DEVICE_ATTR_WO(strobe_pin);
244
lm3642_strobe_brightness_set(struct led_classdev * cdev,enum led_brightness brightness)245 static int lm3642_strobe_brightness_set(struct led_classdev *cdev,
246 enum led_brightness brightness)
247 {
248 struct lm3642_chip_data *chip =
249 container_of(cdev, struct lm3642_chip_data, cdev_flash);
250 int ret;
251
252 mutex_lock(&chip->lock);
253 chip->br_flash = brightness;
254 ret = lm3642_control(chip, chip->br_flash, MODES_FLASH);
255 mutex_unlock(&chip->lock);
256 return ret;
257 }
258
259 /* indicator */
lm3642_indicator_brightness_set(struct led_classdev * cdev,enum led_brightness brightness)260 static int lm3642_indicator_brightness_set(struct led_classdev *cdev,
261 enum led_brightness brightness)
262 {
263 struct lm3642_chip_data *chip =
264 container_of(cdev, struct lm3642_chip_data, cdev_indicator);
265 int ret;
266
267 mutex_lock(&chip->lock);
268 chip->br_indicator = brightness;
269 ret = lm3642_control(chip, chip->br_indicator, MODES_INDIC);
270 mutex_unlock(&chip->lock);
271 return ret;
272 }
273
274 static const struct regmap_config lm3642_regmap = {
275 .reg_bits = 8,
276 .val_bits = 8,
277 .max_register = REG_MAX,
278 };
279
280 static struct attribute *lm3642_flash_attrs[] = {
281 &dev_attr_strobe_pin.attr,
282 NULL
283 };
284 ATTRIBUTE_GROUPS(lm3642_flash);
285
286 static struct attribute *lm3642_torch_attrs[] = {
287 &dev_attr_torch_pin.attr,
288 NULL
289 };
290 ATTRIBUTE_GROUPS(lm3642_torch);
291
lm3642_probe(struct i2c_client * client,const struct i2c_device_id * id)292 static int lm3642_probe(struct i2c_client *client,
293 const struct i2c_device_id *id)
294 {
295 struct lm3642_platform_data *pdata = dev_get_platdata(&client->dev);
296 struct lm3642_chip_data *chip;
297
298 int err;
299
300 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
301 dev_err(&client->dev, "i2c functionality check fail.\n");
302 return -EOPNOTSUPP;
303 }
304
305 if (pdata == NULL) {
306 dev_err(&client->dev, "needs Platform Data.\n");
307 return -ENODATA;
308 }
309
310 chip = devm_kzalloc(&client->dev,
311 sizeof(struct lm3642_chip_data), GFP_KERNEL);
312 if (!chip)
313 return -ENOMEM;
314
315 chip->dev = &client->dev;
316 chip->pdata = pdata;
317
318 chip->tx_pin = pdata->tx_pin;
319 chip->torch_pin = pdata->torch_pin;
320 chip->strobe_pin = pdata->strobe_pin;
321
322 chip->regmap = devm_regmap_init_i2c(client, &lm3642_regmap);
323 if (IS_ERR(chip->regmap)) {
324 err = PTR_ERR(chip->regmap);
325 dev_err(&client->dev, "Failed to allocate register map: %d\n",
326 err);
327 return err;
328 }
329
330 mutex_init(&chip->lock);
331 i2c_set_clientdata(client, chip);
332
333 err = lm3642_chip_init(chip);
334 if (err < 0)
335 goto err_out;
336
337 /* flash */
338 chip->cdev_flash.name = "flash";
339 chip->cdev_flash.max_brightness = 16;
340 chip->cdev_flash.brightness_set_blocking = lm3642_strobe_brightness_set;
341 chip->cdev_flash.default_trigger = "flash";
342 chip->cdev_flash.groups = lm3642_flash_groups;
343 err = led_classdev_register(&client->dev, &chip->cdev_flash);
344 if (err < 0) {
345 dev_err(chip->dev, "failed to register flash\n");
346 goto err_out;
347 }
348
349 /* torch */
350 chip->cdev_torch.name = "torch";
351 chip->cdev_torch.max_brightness = 8;
352 chip->cdev_torch.brightness_set_blocking = lm3642_torch_brightness_set;
353 chip->cdev_torch.default_trigger = "torch";
354 chip->cdev_torch.groups = lm3642_torch_groups;
355 err = led_classdev_register(&client->dev, &chip->cdev_torch);
356 if (err < 0) {
357 dev_err(chip->dev, "failed to register torch\n");
358 goto err_create_torch_file;
359 }
360
361 /* indicator */
362 chip->cdev_indicator.name = "indicator";
363 chip->cdev_indicator.max_brightness = 8;
364 chip->cdev_indicator.brightness_set_blocking =
365 lm3642_indicator_brightness_set;
366 err = led_classdev_register(&client->dev, &chip->cdev_indicator);
367 if (err < 0) {
368 dev_err(chip->dev, "failed to register indicator\n");
369 goto err_create_indicator_file;
370 }
371
372 dev_info(&client->dev, "LM3642 is initialized\n");
373 return 0;
374
375 err_create_indicator_file:
376 led_classdev_unregister(&chip->cdev_torch);
377 err_create_torch_file:
378 led_classdev_unregister(&chip->cdev_flash);
379 err_out:
380 return err;
381 }
382
lm3642_remove(struct i2c_client * client)383 static int lm3642_remove(struct i2c_client *client)
384 {
385 struct lm3642_chip_data *chip = i2c_get_clientdata(client);
386
387 led_classdev_unregister(&chip->cdev_indicator);
388 led_classdev_unregister(&chip->cdev_torch);
389 led_classdev_unregister(&chip->cdev_flash);
390 regmap_write(chip->regmap, REG_ENABLE, 0);
391 return 0;
392 }
393
394 static const struct i2c_device_id lm3642_id[] = {
395 {LM3642_NAME, 0},
396 {}
397 };
398
399 MODULE_DEVICE_TABLE(i2c, lm3642_id);
400
401 static struct i2c_driver lm3642_i2c_driver = {
402 .driver = {
403 .name = LM3642_NAME,
404 .pm = NULL,
405 },
406 .probe = lm3642_probe,
407 .remove = lm3642_remove,
408 .id_table = lm3642_id,
409 };
410
411 module_i2c_driver(lm3642_i2c_driver);
412
413 MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM3642");
414 MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
415 MODULE_AUTHOR("G.Shark Jeong <gshark.jeong@gmail.com>");
416 MODULE_LICENSE("GPL v2");
417