xref: /openbmc/linux/drivers/leds/leds-lm3642.c (revision d9ff8a8e)
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)292 static int lm3642_probe(struct i2c_client *client)
293 {
294 	struct lm3642_platform_data *pdata = dev_get_platdata(&client->dev);
295 	struct lm3642_chip_data *chip;
296 
297 	int err;
298 
299 	if (!i2c_check_functionality(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(&client->dev,
310 			    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(chip->regmap)) {
323 		err = PTR_ERR(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, 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(&client->dev, &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(&client->dev, &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(&client->dev, &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 
374 err_create_indicator_file:
375 	led_classdev_unregister(&chip->cdev_torch);
376 err_create_torch_file:
377 	led_classdev_unregister(&chip->cdev_flash);
378 err_out:
379 	return err;
380 }
381 
lm3642_remove(struct i2c_client * client)382 static void lm3642_remove(struct i2c_client *client)
383 {
384 	struct lm3642_chip_data *chip = i2c_get_clientdata(client);
385 
386 	led_classdev_unregister(&chip->cdev_indicator);
387 	led_classdev_unregister(&chip->cdev_torch);
388 	led_classdev_unregister(&chip->cdev_flash);
389 	regmap_write(chip->regmap, REG_ENABLE, 0);
390 }
391 
392 static const struct i2c_device_id lm3642_id[] = {
393 	{LM3642_NAME, 0},
394 	{}
395 };
396 
397 MODULE_DEVICE_TABLE(i2c, lm3642_id);
398 
399 static 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 
409 module_i2c_driver(lm3642_i2c_driver);
410 
411 MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM3642");
412 MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
413 MODULE_AUTHOR("G.Shark Jeong <gshark.jeong@gmail.com>");
414 MODULE_LICENSE("GPL v2");
415