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
57enum lm3642_mode {
58 MODES_STASNDBY = 0,
59 MODES_INDIC,
60 MODES_TORCH,
61 MODES_FLASH
62};
63
64struct 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 */
87static 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(map: chip->regmap, REG_ENABLE, EX_PIN_ENABLE_MASK,
94 val: 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 */
101static int lm3642_control(struct lm3642_chip_data *chip,
102 u8 brightness, enum lm3642_mode opmode)
103{
104 int ret;
105
106 ret = regmap_read(map: chip->regmap, REG_FLAG, val: &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(map: chip->regmap, REG_I_CTRL,
122 TORCH_I_MASK << TORCH_I_SHIFT,
123 val: (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(map: chip->regmap, REG_I_CTRL,
131 FLASH_I_MASK << FLASH_I_SHIFT,
132 val: (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(map: chip->regmap, REG_I_CTRL,
140 TORCH_I_MASK << TORCH_I_SHIFT,
141 val: (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(map: chip->regmap, REG_ENABLE,
160 MODE_BITS_MASK << MODE_BITS_SHIFT,
161 val: opmode << MODE_BITS_SHIFT);
162 return ret;
163}
164
165/* torch */
166
167/* torch pin config for lm3642 */
168static 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(s: buf, base: 10, res: &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(map: chip->regmap, REG_ENABLE,
186 TORCH_PIN_EN_MASK << TORCH_PIN_EN_SHIFT,
187 val: 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
196static DEVICE_ATTR_WO(torch_pin);
197
198static 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, brightness: chip->br_torch, opmode: MODES_TORCH);
208 mutex_unlock(lock: &chip->lock);
209 return ret;
210}
211
212/* flash */
213
214/* strobe pin config for lm3642*/
215static 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(s: buf, base: 10, res: &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(map: chip->regmap, REG_ENABLE,
233 STROBE_PIN_EN_MASK << STROBE_PIN_EN_SHIFT,
234 val: 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
243static DEVICE_ATTR_WO(strobe_pin);
244
245static 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, brightness: chip->br_flash, opmode: MODES_FLASH);
255 mutex_unlock(lock: &chip->lock);
256 return ret;
257}
258
259/* indicator */
260static 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, brightness: chip->br_indicator, opmode: MODES_INDIC);
270 mutex_unlock(lock: &chip->lock);
271 return ret;
272}
273
274static const struct regmap_config lm3642_regmap = {
275 .reg_bits = 8,
276 .val_bits = 8,
277 .max_register = REG_MAX,
278};
279
280static struct attribute *lm3642_flash_attrs[] = {
281 &dev_attr_strobe_pin.attr,
282 NULL
283};
284ATTRIBUTE_GROUPS(lm3642_flash);
285
286static struct attribute *lm3642_torch_attrs[] = {
287 &dev_attr_torch_pin.attr,
288 NULL
289};
290ATTRIBUTE_GROUPS(lm3642_torch);
291
292static int lm3642_probe(struct i2c_client *client)
293{
294 struct lm3642_platform_data *pdata = dev_get_platdata(dev: &client->dev);
295 struct lm3642_chip_data *chip;
296
297 int err;
298
299 if (!i2c_check_functionality(adap: client->adapter, I2C_FUNC_I2C)) {
300 dev_err(&client->dev, "i2c functionality check fail.\n");
301 return -EOPNOTSUPP;
302 }
303
304 if (pdata == NULL) {
305 dev_err(&client->dev, "needs Platform Data.\n");
306 return -ENODATA;
307 }
308
309 chip = devm_kzalloc(dev: &client->dev,
310 size: sizeof(struct lm3642_chip_data), GFP_KERNEL);
311 if (!chip)
312 return -ENOMEM;
313
314 chip->dev = &client->dev;
315 chip->pdata = pdata;
316
317 chip->tx_pin = pdata->tx_pin;
318 chip->torch_pin = pdata->torch_pin;
319 chip->strobe_pin = pdata->strobe_pin;
320
321 chip->regmap = devm_regmap_init_i2c(client, &lm3642_regmap);
322 if (IS_ERR(ptr: chip->regmap)) {
323 err = PTR_ERR(ptr: chip->regmap);
324 dev_err(&client->dev, "Failed to allocate register map: %d\n",
325 err);
326 return err;
327 }
328
329 mutex_init(&chip->lock);
330 i2c_set_clientdata(client, data: chip);
331
332 err = lm3642_chip_init(chip);
333 if (err < 0)
334 goto err_out;
335
336 /* flash */
337 chip->cdev_flash.name = "flash";
338 chip->cdev_flash.max_brightness = 16;
339 chip->cdev_flash.brightness_set_blocking = lm3642_strobe_brightness_set;
340 chip->cdev_flash.default_trigger = "flash";
341 chip->cdev_flash.groups = lm3642_flash_groups;
342 err = led_classdev_register(parent: &client->dev, led_cdev: &chip->cdev_flash);
343 if (err < 0) {
344 dev_err(chip->dev, "failed to register flash\n");
345 goto err_out;
346 }
347
348 /* torch */
349 chip->cdev_torch.name = "torch";
350 chip->cdev_torch.max_brightness = 8;
351 chip->cdev_torch.brightness_set_blocking = lm3642_torch_brightness_set;
352 chip->cdev_torch.default_trigger = "torch";
353 chip->cdev_torch.groups = lm3642_torch_groups;
354 err = led_classdev_register(parent: &client->dev, led_cdev: &chip->cdev_torch);
355 if (err < 0) {
356 dev_err(chip->dev, "failed to register torch\n");
357 goto err_create_torch_file;
358 }
359
360 /* indicator */
361 chip->cdev_indicator.name = "indicator";
362 chip->cdev_indicator.max_brightness = 8;
363 chip->cdev_indicator.brightness_set_blocking =
364 lm3642_indicator_brightness_set;
365 err = led_classdev_register(parent: &client->dev, led_cdev: &chip->cdev_indicator);
366 if (err < 0) {
367 dev_err(chip->dev, "failed to register indicator\n");
368 goto err_create_indicator_file;
369 }
370
371 dev_info(&client->dev, "LM3642 is initialized\n");
372 return 0;
373
374err_create_indicator_file:
375 led_classdev_unregister(led_cdev: &chip->cdev_torch);
376err_create_torch_file:
377 led_classdev_unregister(led_cdev: &chip->cdev_flash);
378err_out:
379 return err;
380}
381
382static void lm3642_remove(struct i2c_client *client)
383{
384 struct lm3642_chip_data *chip = i2c_get_clientdata(client);
385
386 led_classdev_unregister(led_cdev: &chip->cdev_indicator);
387 led_classdev_unregister(led_cdev: &chip->cdev_torch);
388 led_classdev_unregister(led_cdev: &chip->cdev_flash);
389 regmap_write(map: chip->regmap, REG_ENABLE, val: 0);
390}
391
392static const struct i2c_device_id lm3642_id[] = {
393 {LM3642_NAME, 0},
394 {}
395};
396
397MODULE_DEVICE_TABLE(i2c, lm3642_id);
398
399static struct i2c_driver lm3642_i2c_driver = {
400 .driver = {
401 .name = LM3642_NAME,
402 .pm = NULL,
403 },
404 .probe = lm3642_probe,
405 .remove = lm3642_remove,
406 .id_table = lm3642_id,
407};
408
409module_i2c_driver(lm3642_i2c_driver);
410
411MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM3642");
412MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
413MODULE_AUTHOR("G.Shark Jeong <gshark.jeong@gmail.com>");
414MODULE_LICENSE("GPL v2");
415

source code of linux/drivers/leds/leds-lm3642.c