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(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 */
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(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 */
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(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
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, chip->br_torch, MODES_TORCH);
208	mutex_unlock(&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(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
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, chip->br_flash, MODES_FLASH);
255	mutex_unlock(&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, chip->br_indicator, MODES_INDIC);
270	mutex_unlock(&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(&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
374err_create_indicator_file:
375	led_classdev_unregister(&chip->cdev_torch);
376err_create_torch_file:
377	led_classdev_unregister(&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(&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
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