xref: /openbmc/linux/drivers/leds/leds-lm3642.c (revision 293d5b43)
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/platform_data/leds-lm3642.h>
19 
20 #define	REG_FILT_TIME			(0x0)
21 #define	REG_IVFM_MODE			(0x1)
22 #define	REG_TORCH_TIME			(0x6)
23 #define	REG_FLASH			(0x8)
24 #define	REG_I_CTRL			(0x9)
25 #define	REG_ENABLE			(0xA)
26 #define	REG_FLAG			(0xB)
27 #define	REG_MAX				(0xB)
28 
29 #define	UVLO_EN_SHIFT			(7)
30 #define	IVM_D_TH_SHIFT			(2)
31 #define	TORCH_RAMP_UP_TIME_SHIFT	(3)
32 #define	TORCH_RAMP_DN_TIME_SHIFT	(0)
33 #define	INDUCTOR_I_LIMIT_SHIFT		(6)
34 #define	FLASH_RAMP_TIME_SHIFT		(3)
35 #define	FLASH_TOUT_TIME_SHIFT		(0)
36 #define	TORCH_I_SHIFT			(4)
37 #define	FLASH_I_SHIFT			(0)
38 #define	IVFM_SHIFT			(7)
39 #define	TX_PIN_EN_SHIFT			(6)
40 #define	STROBE_PIN_EN_SHIFT		(5)
41 #define	TORCH_PIN_EN_SHIFT		(4)
42 #define	MODE_BITS_SHIFT			(0)
43 
44 #define	UVLO_EN_MASK			(0x1)
45 #define	IVM_D_TH_MASK			(0x7)
46 #define	TORCH_RAMP_UP_TIME_MASK		(0x7)
47 #define	TORCH_RAMP_DN_TIME_MASK		(0x7)
48 #define	INDUCTOR_I_LIMIT_MASK		(0x1)
49 #define	FLASH_RAMP_TIME_MASK		(0x7)
50 #define	FLASH_TOUT_TIME_MASK		(0x7)
51 #define	TORCH_I_MASK			(0x7)
52 #define	FLASH_I_MASK			(0xF)
53 #define	IVFM_MASK			(0x1)
54 #define	TX_PIN_EN_MASK			(0x1)
55 #define	STROBE_PIN_EN_MASK		(0x1)
56 #define	TORCH_PIN_EN_MASK		(0x1)
57 #define	MODE_BITS_MASK			(0x73)
58 #define EX_PIN_CONTROL_MASK		(0x71)
59 #define EX_PIN_ENABLE_MASK		(0x70)
60 
61 enum lm3642_mode {
62 	MODES_STASNDBY = 0,
63 	MODES_INDIC,
64 	MODES_TORCH,
65 	MODES_FLASH
66 };
67 
68 struct lm3642_chip_data {
69 	struct device *dev;
70 
71 	struct led_classdev cdev_flash;
72 	struct led_classdev cdev_torch;
73 	struct led_classdev cdev_indicator;
74 
75 	u8 br_flash;
76 	u8 br_torch;
77 	u8 br_indicator;
78 
79 	enum lm3642_torch_pin_enable torch_pin;
80 	enum lm3642_strobe_pin_enable strobe_pin;
81 	enum lm3642_tx_pin_enable tx_pin;
82 
83 	struct lm3642_platform_data *pdata;
84 	struct regmap *regmap;
85 	struct mutex lock;
86 
87 	unsigned int last_flag;
88 };
89 
90 /* chip initialize */
91 static int lm3642_chip_init(struct lm3642_chip_data *chip)
92 {
93 	int ret;
94 	struct lm3642_platform_data *pdata = chip->pdata;
95 
96 	/* set enable register */
97 	ret = regmap_update_bits(chip->regmap, REG_ENABLE, EX_PIN_ENABLE_MASK,
98 				 pdata->tx_pin);
99 	if (ret < 0)
100 		dev_err(chip->dev, "Failed to update REG_ENABLE Register\n");
101 	return ret;
102 }
103 
104 /* chip control */
105 static int lm3642_control(struct lm3642_chip_data *chip,
106 			  u8 brightness, enum lm3642_mode opmode)
107 {
108 	int ret;
109 
110 	ret = regmap_read(chip->regmap, REG_FLAG, &chip->last_flag);
111 	if (ret < 0) {
112 		dev_err(chip->dev, "Failed to read REG_FLAG Register\n");
113 		goto out;
114 	}
115 
116 	if (chip->last_flag)
117 		dev_info(chip->dev, "Last FLAG is 0x%x\n", chip->last_flag);
118 
119 	/* brightness 0 means off-state */
120 	if (!brightness)
121 		opmode = MODES_STASNDBY;
122 
123 	switch (opmode) {
124 	case MODES_TORCH:
125 		ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
126 					 TORCH_I_MASK << TORCH_I_SHIFT,
127 					 (brightness - 1) << TORCH_I_SHIFT);
128 
129 		if (chip->torch_pin)
130 			opmode |= (TORCH_PIN_EN_MASK << TORCH_PIN_EN_SHIFT);
131 		break;
132 
133 	case MODES_FLASH:
134 		ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
135 					 FLASH_I_MASK << FLASH_I_SHIFT,
136 					 (brightness - 1) << FLASH_I_SHIFT);
137 
138 		if (chip->strobe_pin)
139 			opmode |= (STROBE_PIN_EN_MASK << STROBE_PIN_EN_SHIFT);
140 		break;
141 
142 	case MODES_INDIC:
143 		ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
144 					 TORCH_I_MASK << TORCH_I_SHIFT,
145 					 (brightness - 1) << TORCH_I_SHIFT);
146 		break;
147 
148 	case MODES_STASNDBY:
149 
150 		break;
151 
152 	default:
153 		return ret;
154 	}
155 	if (ret < 0) {
156 		dev_err(chip->dev, "Failed to write REG_I_CTRL Register\n");
157 		goto out;
158 	}
159 
160 	if (chip->tx_pin)
161 		opmode |= (TX_PIN_EN_MASK << TX_PIN_EN_SHIFT);
162 
163 	ret = regmap_update_bits(chip->regmap, REG_ENABLE,
164 				 MODE_BITS_MASK << MODE_BITS_SHIFT,
165 				 opmode << MODE_BITS_SHIFT);
166 out:
167 	return ret;
168 }
169 
170 /* torch */
171 
172 /* torch pin config for lm3642*/
173 static ssize_t lm3642_torch_pin_store(struct device *dev,
174 				      struct device_attribute *attr,
175 				      const char *buf, size_t size)
176 {
177 	ssize_t ret;
178 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
179 	struct lm3642_chip_data *chip =
180 	    container_of(led_cdev, struct lm3642_chip_data, cdev_indicator);
181 	unsigned int state;
182 
183 	ret = kstrtouint(buf, 10, &state);
184 	if (ret)
185 		goto out_strtoint;
186 	if (state != 0)
187 		state = 0x01 << TORCH_PIN_EN_SHIFT;
188 
189 	chip->torch_pin = state;
190 	ret = regmap_update_bits(chip->regmap, REG_ENABLE,
191 				 TORCH_PIN_EN_MASK << TORCH_PIN_EN_SHIFT,
192 				 state);
193 	if (ret < 0)
194 		goto out;
195 
196 	return size;
197 out:
198 	dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
199 	return ret;
200 out_strtoint:
201 	dev_err(chip->dev, "%s: fail to change str to int\n", __func__);
202 	return ret;
203 }
204 
205 static DEVICE_ATTR(torch_pin, S_IWUSR, NULL, lm3642_torch_pin_store);
206 
207 static int lm3642_torch_brightness_set(struct led_classdev *cdev,
208 					enum led_brightness brightness)
209 {
210 	struct lm3642_chip_data *chip =
211 	    container_of(cdev, struct lm3642_chip_data, cdev_torch);
212 	int ret;
213 
214 	mutex_lock(&chip->lock);
215 	chip->br_torch = brightness;
216 	ret = lm3642_control(chip, chip->br_torch, MODES_TORCH);
217 	mutex_unlock(&chip->lock);
218 	return ret;
219 }
220 
221 /* flash */
222 
223 /* strobe pin config for lm3642*/
224 static ssize_t lm3642_strobe_pin_store(struct device *dev,
225 				       struct device_attribute *attr,
226 				       const char *buf, size_t size)
227 {
228 	ssize_t ret;
229 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
230 	struct lm3642_chip_data *chip =
231 	    container_of(led_cdev, struct lm3642_chip_data, cdev_indicator);
232 	unsigned int state;
233 
234 	ret = kstrtouint(buf, 10, &state);
235 	if (ret)
236 		goto out_strtoint;
237 	if (state != 0)
238 		state = 0x01 << STROBE_PIN_EN_SHIFT;
239 
240 	chip->strobe_pin = state;
241 	ret = regmap_update_bits(chip->regmap, REG_ENABLE,
242 				 STROBE_PIN_EN_MASK << STROBE_PIN_EN_SHIFT,
243 				 state);
244 	if (ret < 0)
245 		goto out;
246 
247 	return size;
248 out:
249 	dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
250 	return ret;
251 out_strtoint:
252 	dev_err(chip->dev, "%s: fail to change str to int\n", __func__);
253 	return ret;
254 }
255 
256 static DEVICE_ATTR(strobe_pin, S_IWUSR, NULL, lm3642_strobe_pin_store);
257 
258 static int lm3642_strobe_brightness_set(struct led_classdev *cdev,
259 					 enum led_brightness brightness)
260 {
261 	struct lm3642_chip_data *chip =
262 	    container_of(cdev, struct lm3642_chip_data, cdev_flash);
263 	int ret;
264 
265 	mutex_lock(&chip->lock);
266 	chip->br_flash = brightness;
267 	ret = lm3642_control(chip, chip->br_flash, MODES_FLASH);
268 	mutex_unlock(&chip->lock);
269 	return ret;
270 }
271 
272 /* indicator */
273 static int lm3642_indicator_brightness_set(struct led_classdev *cdev,
274 					    enum led_brightness brightness)
275 {
276 	struct lm3642_chip_data *chip =
277 	    container_of(cdev, struct lm3642_chip_data, cdev_indicator);
278 	int ret;
279 
280 	mutex_lock(&chip->lock);
281 	chip->br_indicator = brightness;
282 	ret = lm3642_control(chip, chip->br_indicator, MODES_INDIC);
283 	mutex_unlock(&chip->lock);
284 	return ret;
285 }
286 
287 static const struct regmap_config lm3642_regmap = {
288 	.reg_bits = 8,
289 	.val_bits = 8,
290 	.max_register = REG_MAX,
291 };
292 
293 static struct attribute *lm3642_flash_attrs[] = {
294 	&dev_attr_strobe_pin.attr,
295 	NULL
296 };
297 ATTRIBUTE_GROUPS(lm3642_flash);
298 
299 static struct attribute *lm3642_torch_attrs[] = {
300 	&dev_attr_torch_pin.attr,
301 	NULL
302 };
303 ATTRIBUTE_GROUPS(lm3642_torch);
304 
305 static int lm3642_probe(struct i2c_client *client,
306 				  const struct i2c_device_id *id)
307 {
308 	struct lm3642_platform_data *pdata = dev_get_platdata(&client->dev);
309 	struct lm3642_chip_data *chip;
310 
311 	int err;
312 
313 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
314 		dev_err(&client->dev, "i2c functionality check fail.\n");
315 		return -EOPNOTSUPP;
316 	}
317 
318 	if (pdata == NULL) {
319 		dev_err(&client->dev, "needs Platform Data.\n");
320 		return -ENODATA;
321 	}
322 
323 	chip = devm_kzalloc(&client->dev,
324 			    sizeof(struct lm3642_chip_data), GFP_KERNEL);
325 	if (!chip)
326 		return -ENOMEM;
327 
328 	chip->dev = &client->dev;
329 	chip->pdata = pdata;
330 
331 	chip->tx_pin = pdata->tx_pin;
332 	chip->torch_pin = pdata->torch_pin;
333 	chip->strobe_pin = pdata->strobe_pin;
334 
335 	chip->regmap = devm_regmap_init_i2c(client, &lm3642_regmap);
336 	if (IS_ERR(chip->regmap)) {
337 		err = PTR_ERR(chip->regmap);
338 		dev_err(&client->dev, "Failed to allocate register map: %d\n",
339 			err);
340 		return err;
341 	}
342 
343 	mutex_init(&chip->lock);
344 	i2c_set_clientdata(client, chip);
345 
346 	err = lm3642_chip_init(chip);
347 	if (err < 0)
348 		goto err_out;
349 
350 	/* flash */
351 	chip->cdev_flash.name = "flash";
352 	chip->cdev_flash.max_brightness = 16;
353 	chip->cdev_flash.brightness_set_blocking = lm3642_strobe_brightness_set;
354 	chip->cdev_flash.default_trigger = "flash";
355 	chip->cdev_flash.groups = lm3642_flash_groups,
356 	err = led_classdev_register((struct device *)
357 				    &client->dev, &chip->cdev_flash);
358 	if (err < 0) {
359 		dev_err(chip->dev, "failed to register flash\n");
360 		goto err_out;
361 	}
362 
363 	/* torch */
364 	chip->cdev_torch.name = "torch";
365 	chip->cdev_torch.max_brightness = 8;
366 	chip->cdev_torch.brightness_set_blocking = lm3642_torch_brightness_set;
367 	chip->cdev_torch.default_trigger = "torch";
368 	chip->cdev_torch.groups = lm3642_torch_groups,
369 	err = led_classdev_register((struct device *)
370 				    &client->dev, &chip->cdev_torch);
371 	if (err < 0) {
372 		dev_err(chip->dev, "failed to register torch\n");
373 		goto err_create_torch_file;
374 	}
375 
376 	/* indicator */
377 	chip->cdev_indicator.name = "indicator";
378 	chip->cdev_indicator.max_brightness = 8;
379 	chip->cdev_indicator.brightness_set_blocking =
380 						lm3642_indicator_brightness_set;
381 	err = led_classdev_register((struct device *)
382 				    &client->dev, &chip->cdev_indicator);
383 	if (err < 0) {
384 		dev_err(chip->dev, "failed to register indicator\n");
385 		goto err_create_indicator_file;
386 	}
387 
388 	dev_info(&client->dev, "LM3642 is initialized\n");
389 	return 0;
390 
391 err_create_indicator_file:
392 	led_classdev_unregister(&chip->cdev_torch);
393 err_create_torch_file:
394 	led_classdev_unregister(&chip->cdev_flash);
395 err_out:
396 	return err;
397 }
398 
399 static int lm3642_remove(struct i2c_client *client)
400 {
401 	struct lm3642_chip_data *chip = i2c_get_clientdata(client);
402 
403 	led_classdev_unregister(&chip->cdev_indicator);
404 	led_classdev_unregister(&chip->cdev_torch);
405 	led_classdev_unregister(&chip->cdev_flash);
406 	regmap_write(chip->regmap, REG_ENABLE, 0);
407 	return 0;
408 }
409 
410 static const struct i2c_device_id lm3642_id[] = {
411 	{LM3642_NAME, 0},
412 	{}
413 };
414 
415 MODULE_DEVICE_TABLE(i2c, lm3642_id);
416 
417 static struct i2c_driver lm3642_i2c_driver = {
418 	.driver = {
419 		   .name = LM3642_NAME,
420 		   .pm = NULL,
421 		   },
422 	.probe = lm3642_probe,
423 	.remove = lm3642_remove,
424 	.id_table = lm3642_id,
425 };
426 
427 module_i2c_driver(lm3642_i2c_driver);
428 
429 MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM3642");
430 MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
431 MODULE_AUTHOR("G.Shark Jeong <gshark.jeong@gmail.com>");
432 MODULE_LICENSE("GPL v2");
433