[linux.git] / drivers / leds / leds-lm3692x.c

/*
 * TI lm3692x LED Driver
 *
 * Copyright (C) 2017 Texas Instruments
 *
 * Author: Dan Murphy <[email protected]>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * Data sheet is located
 * http://www.ti.com/lit/ds/snvsa29/snvsa29.pdf
 */

#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
#include <uapi/linux/uleds.h>

#define LM3692X_REV		0x0
#define LM3692X_RESET		0x1
#define LM3692X_EN		0x10
#define LM3692X_BRT_CTRL	0x11
#define LM3692X_PWM_CTRL	0x12
#define LM3692X_BOOST_CTRL	0x13
#define LM3692X_AUTO_FREQ_HI	0x15
#define LM3692X_AUTO_FREQ_LO	0x16
#define LM3692X_BL_ADJ_THRESH	0x17
#define LM3692X_BRT_LSB		0x18
#define LM3692X_BRT_MSB		0x19
#define LM3692X_FAULT_CTRL	0x1e
#define LM3692X_FAULT_FLAGS	0x1f

#define LM3692X_SW_RESET	BIT(0)
#define LM3692X_DEVICE_EN	BIT(0)
#define LM3692X_LED1_EN		BIT(1)
#define LM3692X_LED2_EN		BIT(2)

/* Brightness Control Bits */
#define LM3692X_BL_ADJ_POL	BIT(0)
#define LM3692X_RAMP_RATE_125us	0x00
#define LM3692X_RAMP_RATE_250us	BIT(1)
#define LM3692X_RAMP_RATE_500us BIT(2)
#define LM3692X_RAMP_RATE_1ms	(BIT(1) | BIT(2))
#define LM3692X_RAMP_RATE_2ms	BIT(3)
#define LM3692X_RAMP_RATE_4ms	(BIT(3) | BIT(1))
#define LM3692X_RAMP_RATE_8ms	(BIT(2) | BIT(3))
#define LM3692X_RAMP_RATE_16ms	(BIT(1) | BIT(2) | BIT(3))
#define LM3692X_RAMP_EN		BIT(4)
#define LM3692X_BRHT_MODE_REG	0x00
#define LM3692X_BRHT_MODE_PWM	BIT(5)
#define LM3692X_BRHT_MODE_MULTI_RAMP BIT(6)
#define LM3692X_BRHT_MODE_RAMP_MULTI (BIT(5) | BIT(6))
#define LM3692X_MAP_MODE_EXP	BIT(7)

/* PWM Register Bits */
#define LM3692X_PWM_FILTER_100	BIT(0)
#define LM3692X_PWM_FILTER_150	BIT(1)
#define LM3692X_PWM_FILTER_200	(BIT(0) | BIT(1))
#define LM3692X_PWM_HYSTER_1LSB BIT(2)
#define LM3692X_PWM_HYSTER_2LSB	BIT(3)
#define LM3692X_PWM_HYSTER_3LSB (BIT(3) | BIT(2))
#define LM3692X_PWM_HYSTER_4LSB BIT(4)
#define LM3692X_PWM_HYSTER_5LSB (BIT(4) | BIT(2))
#define LM3692X_PWM_HYSTER_6LSB (BIT(4) | BIT(3))
#define LM3692X_PWM_POLARITY	BIT(5)
#define LM3692X_PWM_SAMP_4MHZ	BIT(6)
#define LM3692X_PWM_SAMP_24MHZ	BIT(7)

/* Boost Control Bits */
#define LM3692X_OCP_PROT_1A	BIT(0)
#define LM3692X_OCP_PROT_1_25A	BIT(1)
#define LM3692X_OCP_PROT_1_5A	(BIT(0) | BIT(1))
#define LM3692X_OVP_21V		BIT(2)
#define LM3692X_OVP_25V		BIT(3)
#define LM3692X_OVP_29V		(BIT(2) | BIT(3))
#define LM3692X_MIN_IND_22UH	BIT(4)
#define LM3692X_BOOST_SW_1MHZ	BIT(5)
#define LM3692X_BOOST_SW_NO_SHIFT	BIT(6)

/* Fault Control Bits */
#define LM3692X_FAULT_CTRL_OVP BIT(0)
#define LM3692X_FAULT_CTRL_OCP BIT(1)
#define LM3692X_FAULT_CTRL_TSD BIT(2)
#define LM3692X_FAULT_CTRL_OPEN BIT(3)

/* Fault Flag Bits */
#define LM3692X_FAULT_FLAG_OVP BIT(0)
#define LM3692X_FAULT_FLAG_OCP BIT(1)
#define LM3692X_FAULT_FLAG_TSD BIT(2)
#define LM3692X_FAULT_FLAG_SHRT BIT(3)
#define LM3692X_FAULT_FLAG_OPEN BIT(4)

/**
 * struct lm3692x_led -
 * @lock - Lock for reading/writing the device
 * @client - Pointer to the I2C client
 * @led_dev - LED class device pointer
 * @regmap - Devices register map
 * @enable_gpio - VDDIO/EN gpio to enable communication interface
 * @regulator - LED supply regulator pointer
 * @label - LED label
 */
struct lm3692x_led {
	struct mutex lock;
	struct i2c_client *client;
	struct led_classdev led_dev;
	struct regmap *regmap;
	struct gpio_desc *enable_gpio;
	struct regulator *regulator;
	char label[LED_MAX_NAME_SIZE];
};

static const struct reg_default lm3692x_reg_defs[] = {
	{LM3692X_EN, 0xf},
	{LM3692X_BRT_CTRL, 0x61},
	{LM3692X_PWM_CTRL, 0x73},
	{LM3692X_BOOST_CTRL, 0x6f},
	{LM3692X_AUTO_FREQ_HI, 0x0},
	{LM3692X_AUTO_FREQ_LO, 0x0},
	{LM3692X_BL_ADJ_THRESH, 0x0},
	{LM3692X_BRT_LSB, 0x7},
	{LM3692X_BRT_MSB, 0xff},
	{LM3692X_FAULT_CTRL, 0x7},
};

static const struct regmap_config lm3692x_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,

	.max_register = LM3692X_FAULT_FLAGS,
	.reg_defaults = lm3692x_reg_defs,
	.num_reg_defaults = ARRAY_SIZE(lm3692x_reg_defs),
	.cache_type = REGCACHE_RBTREE,
};

static int lm3692x_fault_check(struct lm3692x_led *led)
{
	int ret;
	unsigned int read_buf;

	ret = regmap_read(led->regmap, LM3692X_FAULT_FLAGS, &read_buf);
	if (ret)
		return ret;

	if (read_buf)
		dev_err(&led->client->dev, "Detected a fault 0x%X\n", read_buf);

	/* The first read may clear the fault.  Check again to see if the fault
	 * still exits and return that value.
	 */
	regmap_read(led->regmap, LM3692X_FAULT_FLAGS, &read_buf);
	if (read_buf)
		dev_err(&led->client->dev, "Second read of fault flags 0x%X\n",
			read_buf);

	return read_buf;
}

static int lm3692x_brightness_set(struct led_classdev *led_cdev,
				enum led_brightness brt_val)
{
	struct lm3692x_led *led =
			container_of(led_cdev, struct lm3692x_led, led_dev);
	int ret;
	int led_brightness_lsb = (brt_val >> 5);

	mutex_lock(&led->lock);

	ret = lm3692x_fault_check(led);
	if (ret) {
		dev_err(&led->client->dev, "Cannot read/clear faults\n");
		goto out;
	}

	ret = regmap_write(led->regmap, LM3692X_BRT_MSB, brt_val);
	if (ret) {
		dev_err(&led->client->dev, "Cannot write MSB\n");
		goto out;
	}

	ret = regmap_write(led->regmap, LM3692X_BRT_LSB, led_brightness_lsb);
	if (ret) {
		dev_err(&led->client->dev, "Cannot write LSB\n");
		goto out;
	}
out:
	mutex_unlock(&led->lock);
	return ret;
}

static int lm3692x_init(struct lm3692x_led *led)
{
	int ret;

	if (led->regulator) {
		ret = regulator_enable(led->regulator);
		if (ret) {
			dev_err(&led->client->dev,
				"Failed to enable regulator\n");
			return ret;
		}
	}

	if (led->enable_gpio)
		gpiod_direction_output(led->enable_gpio, 1);

	ret = lm3692x_fault_check(led);
	if (ret) {
		dev_err(&led->client->dev, "Cannot read/clear faults\n");
		goto out;
	}

	ret = regmap_write(led->regmap, LM3692X_BRT_CTRL, 0x00);
	if (ret)
		goto out;

	/*
	 * For glitch free operation, the following data should
	 * only be written while device enable bit is 0
	 * per Section 7.5.14 of the data sheet
	 */
	ret = regmap_write(led->regmap, LM3692X_PWM_CTRL,
		LM3692X_PWM_FILTER_100 | LM3692X_PWM_SAMP_24MHZ);
	if (ret)
		goto out;

	ret = regmap_write(led->regmap, LM3692X_BOOST_CTRL,
			LM3692X_BRHT_MODE_RAMP_MULTI |
			LM3692X_BL_ADJ_POL |
			LM3692X_RAMP_RATE_250us);
	if (ret)
		goto out;

	ret = regmap_write(led->regmap, LM3692X_AUTO_FREQ_HI, 0x00);
	if (ret)
		goto out;

	ret = regmap_write(led->regmap, LM3692X_AUTO_FREQ_LO, 0x00);
	if (ret)
		goto out;

	ret = regmap_write(led->regmap, LM3692X_BL_ADJ_THRESH, 0x00);
	if (ret)
		goto out;

	ret = regmap_write(led->regmap, LM3692X_BRT_CTRL,
			LM3692X_BL_ADJ_POL | LM3692X_PWM_HYSTER_4LSB);
	if (ret)
		goto out;

	return ret;
out:
	dev_err(&led->client->dev, "Fail writing initialization values\n");

	if (led->enable_gpio)
		gpiod_direction_output(led->enable_gpio, 0);

	if (led->regulator) {
		ret = regulator_disable(led->regulator);
		if (ret)
			dev_err(&led->client->dev,
				"Failed to disable regulator\n");
	}

	return ret;
}

static int lm3692x_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	int ret;
	struct lm3692x_led *led;
	struct device_node *np = client->dev.of_node;
	struct device_node *child_node;
	const char *name;

	led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
	if (!led)
		return -ENOMEM;

	for_each_available_child_of_node(np, child_node) {
		led->led_dev.default_trigger = of_get_property(child_node,
						    "linux,default-trigger",
						    NULL);

		ret = of_property_read_string(child_node, "label", &name);
		if (!ret)
			snprintf(led->label, sizeof(led->label),
				 "%s:%s", id->name, name);
		else
			snprintf(led->label, sizeof(led->label),
				 "%s::backlight_cluster", id->name);
	};

	led->enable_gpio = devm_gpiod_get_optional(&client->dev,
						   "enable", GPIOD_OUT_LOW);
	if (IS_ERR(led->enable_gpio)) {
		ret = PTR_ERR(led->enable_gpio);
		dev_err(&client->dev, "Failed to get enable gpio: %d\n", ret);
		return ret;
	}

	led->regulator = devm_regulator_get(&client->dev, "vled");
	if (IS_ERR(led->regulator))
		led->regulator = NULL;

	led->client = client;
	led->led_dev.name = led->label;
	led->led_dev.brightness_set_blocking = lm3692x_brightness_set;

	mutex_init(&led->lock);

	i2c_set_clientdata(client, led);

	led->regmap = devm_regmap_init_i2c(client, &lm3692x_regmap_config);
	if (IS_ERR(led->regmap)) {
		ret = PTR_ERR(led->regmap);
		dev_err(&client->dev, "Failed to allocate register map: %d\n",
			ret);
		return ret;
	}

	ret = lm3692x_init(led);
	if (ret)
		return ret;

	ret = devm_led_classdev_register(&client->dev, &led->led_dev);
	if (ret) {
		dev_err(&client->dev, "led register err: %d\n", ret);
		return ret;
	}

	return 0;
}

static int lm3692x_remove(struct i2c_client *client)
{
	struct lm3692x_led *led = i2c_get_clientdata(client);
	int ret;

	if (led->enable_gpio)
		gpiod_direction_output(led->enable_gpio, 0);

	if (led->regulator) {
		ret = regulator_disable(led->regulator);
		if (ret)
			dev_err(&led->client->dev,
				"Failed to disable regulator\n");
	}

	mutex_destroy(&led->lock);

	return 0;
}

static const struct i2c_device_id lm3692x_id[] = {
	{ "lm36922", 0 },
	{ "lm36923", 1 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, lm3692x_id);

static const struct of_device_id of_lm3692x_leds_match[] = {
	{ .compatible = "ti,lm36922", },
	{ .compatible = "ti,lm36923", },
	{},
};
MODULE_DEVICE_TABLE(of, of_lm3692x_leds_match);

static struct i2c_driver lm3692x_driver = {
	.driver = {
		.name	= "lm3692x",
		.of_match_table = of_lm3692x_leds_match,
	},
	.probe		= lm3692x_probe,
	.remove		= lm3692x_remove,
	.id_table	= lm3692x_id,
};
module_i2c_driver(lm3692x_driver);

MODULE_DESCRIPTION("Texas Instruments LM3692X LED driver");
MODULE_AUTHOR("Dan Murphy <[email protected]>");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
9699cb6b DM	1	/*
	2	* TI lm3692x LED Driver
	3	*
	4	* Copyright (C) 2017 Texas Instruments
	5	*
	6	* Author: Dan Murphy <[email protected]>
	7	*
	8	* This program is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU General Public License
	10	* version 2 as published by the Free Software Foundation.
	11	*
	12	* Data sheet is located
	13	* http://www.ti.com/lit/ds/snvsa29/snvsa29.pdf
	14	*/
	15
	16	#include <linux/gpio/consumer.h>
	17	#include <linux/i2c.h>
	18	#include <linux/init.h>
	19	#include <linux/leds.h>
	20	#include <linux/module.h>
	21	#include <linux/mutex.h>
	22	#include <linux/of.h>
	23	#include <linux/of_gpio.h>
	24	#include <linux/regmap.h>
	25	#include <linux/regulator/consumer.h>
	26	#include <linux/slab.h>
	27	#include <uapi/linux/uleds.h>
	28
	29	#define LM3692X_REV 0x0
	30	#define LM3692X_RESET 0x1
	31	#define LM3692X_EN 0x10
	32	#define LM3692X_BRT_CTRL 0x11
	33	#define LM3692X_PWM_CTRL 0x12
	34	#define LM3692X_BOOST_CTRL 0x13
	35	#define LM3692X_AUTO_FREQ_HI 0x15
	36	#define LM3692X_AUTO_FREQ_LO 0x16
	37	#define LM3692X_BL_ADJ_THRESH 0x17
	38	#define LM3692X_BRT_LSB 0x18
	39	#define LM3692X_BRT_MSB 0x19
	40	#define LM3692X_FAULT_CTRL 0x1e
	41	#define LM3692X_FAULT_FLAGS 0x1f
	42
	43	#define LM3692X_SW_RESET BIT(0)
	44	#define LM3692X_DEVICE_EN BIT(0)
	45	#define LM3692X_LED1_EN BIT(1)
	46	#define LM3692X_LED2_EN BIT(2)
	47
	48	/* Brightness Control Bits */
	49	#define LM3692X_BL_ADJ_POL BIT(0)
	50	#define LM3692X_RAMP_RATE_125us 0x00
	51	#define LM3692X_RAMP_RATE_250us BIT(1)
	52	#define LM3692X_RAMP_RATE_500us BIT(2)
	53	#define LM3692X_RAMP_RATE_1ms (BIT(1) \| BIT(2))
	54	#define LM3692X_RAMP_RATE_2ms BIT(3)
	55	#define LM3692X_RAMP_RATE_4ms (BIT(3) \| BIT(1))
	56	#define LM3692X_RAMP_RATE_8ms (BIT(2) \| BIT(3))
	57	#define LM3692X_RAMP_RATE_16ms (BIT(1) \| BIT(2) \| BIT(3))
	58	#define LM3692X_RAMP_EN BIT(4)
	59	#define LM3692X_BRHT_MODE_REG 0x00
	60	#define LM3692X_BRHT_MODE_PWM BIT(5)
	61	#define LM3692X_BRHT_MODE_MULTI_RAMP BIT(6)
	62	#define LM3692X_BRHT_MODE_RAMP_MULTI (BIT(5) \| BIT(6))
	63	#define LM3692X_MAP_MODE_EXP BIT(7)
	64
65	/* PWM Register Bits */
66	#define LM3692X_PWM_FILTER_100 BIT(0)
67	#define LM3692X_PWM_FILTER_150 BIT(1)
68	#define LM3692X_PWM_FILTER_200 (BIT(0) \| BIT(1))
69	#define LM3692X_PWM_HYSTER_1LSB BIT(2)
70	#define LM3692X_PWM_HYSTER_2LSB BIT(3)
71	#define LM3692X_PWM_HYSTER_3LSB (BIT(3) \| BIT(2))
72	#define LM3692X_PWM_HYSTER_4LSB BIT(4)
73	#define LM3692X_PWM_HYSTER_5LSB (BIT(4) \| BIT(2))
74	#define LM3692X_PWM_HYSTER_6LSB (BIT(4) \| BIT(3))
75	#define LM3692X_PWM_POLARITY BIT(5)
76	#define LM3692X_PWM_SAMP_4MHZ BIT(6)
77	#define LM3692X_PWM_SAMP_24MHZ BIT(7)
78
79	/* Boost Control Bits */
80	#define LM3692X_OCP_PROT_1A BIT(0)
81	#define LM3692X_OCP_PROT_1_25A BIT(1)
82	#define LM3692X_OCP_PROT_1_5A (BIT(0) \| BIT(1))
83	#define LM3692X_OVP_21V BIT(2)
84	#define LM3692X_OVP_25V BIT(3)
85	#define LM3692X_OVP_29V (BIT(2) \| BIT(3))
86	#define LM3692X_MIN_IND_22UH BIT(4)
87	#define LM3692X_BOOST_SW_1MHZ BIT(5)
88	#define LM3692X_BOOST_SW_NO_SHIFT BIT(6)
89
90	/* Fault Control Bits */
91	#define LM3692X_FAULT_CTRL_OVP BIT(0)
92	#define LM3692X_FAULT_CTRL_OCP BIT(1)
93	#define LM3692X_FAULT_CTRL_TSD BIT(2)
94	#define LM3692X_FAULT_CTRL_OPEN BIT(3)
95
96	/* Fault Flag Bits */
97	#define LM3692X_FAULT_FLAG_OVP BIT(0)
98	#define LM3692X_FAULT_FLAG_OCP BIT(1)
99	#define LM3692X_FAULT_FLAG_TSD BIT(2)
100	#define LM3692X_FAULT_FLAG_SHRT BIT(3)
101	#define LM3692X_FAULT_FLAG_OPEN BIT(4)
102
103	/**
104	* struct lm3692x_led -
105	* @lock - Lock for reading/writing the device
106	* @client - Pointer to the I2C client
107	* @led_dev - LED class device pointer
108	* @regmap - Devices register map
109	* @enable_gpio - VDDIO/EN gpio to enable communication interface
110	* @regulator - LED supply regulator pointer
111	* @label - LED label
112	*/
113	struct lm3692x_led {
114	struct mutex lock;
115	struct i2c_client *client;
116	struct led_classdev led_dev;
117	struct regmap *regmap;
118	struct gpio_desc *enable_gpio;
119	struct regulator *regulator;
120	char label[LED_MAX_NAME_SIZE];
121	};
122
123	static const struct reg_default lm3692x_reg_defs[] = {
124	{LM3692X_EN, 0xf},
125	{LM3692X_BRT_CTRL, 0x61},
126	{LM3692X_PWM_CTRL, 0x73},
127	{LM3692X_BOOST_CTRL, 0x6f},
128	{LM3692X_AUTO_FREQ_HI, 0x0},
129	{LM3692X_AUTO_FREQ_LO, 0x0},
130	{LM3692X_BL_ADJ_THRESH, 0x0},
131	{LM3692X_BRT_LSB, 0x7},
132	{LM3692X_BRT_MSB, 0xff},
133	{LM3692X_FAULT_CTRL, 0x7},
134	};
135
136	static const struct regmap_config lm3692x_regmap_config = {
137	.reg_bits = 8,
138	.val_bits = 8,
139
140	.max_register = LM3692X_FAULT_FLAGS,
141	.reg_defaults = lm3692x_reg_defs,
142	.num_reg_defaults = ARRAY_SIZE(lm3692x_reg_defs),
143	.cache_type = REGCACHE_RBTREE,
144	};
145
146	static int lm3692x_fault_check(struct lm3692x_led *led)
147	{
148	int ret;
149	unsigned int read_buf;
150
151	ret = regmap_read(led->regmap, LM3692X_FAULT_FLAGS, &read_buf);
152	if (ret)
153	return ret;
154
155	if (read_buf)
156	dev_err(&led->client->dev, "Detected a fault 0x%X\n", read_buf);
157
158	/* The first read may clear the fault. Check again to see if the fault
159	* still exits and return that value.
160	*/
161	regmap_read(led->regmap, LM3692X_FAULT_FLAGS, &read_buf);
162	if (read_buf)
163	dev_err(&led->client->dev, "Second read of fault flags 0x%X\n",
164	read_buf);
165
166	return read_buf;
167	}
168
169	static int lm3692x_brightness_set(struct led_classdev *led_cdev,
170	enum led_brightness brt_val)
171	{
172	struct lm3692x_led *led =
173	container_of(led_cdev, struct lm3692x_led, led_dev);
174	int ret;
175	int led_brightness_lsb = (brt_val >> 5);
176
177	mutex_lock(&led->lock);
178
179	ret = lm3692x_fault_check(led);
180	if (ret) {
181	dev_err(&led->client->dev, "Cannot read/clear faults\n");
182	goto out;
183	}
184
185	ret = regmap_write(led->regmap, LM3692X_BRT_MSB, brt_val);
186	if (ret) {
187	dev_err(&led->client->dev, "Cannot write MSB\n");
188	goto out;
189	}
190
191	ret = regmap_write(led->regmap, LM3692X_BRT_LSB, led_brightness_lsb);
192	if (ret) {
193	dev_err(&led->client->dev, "Cannot write LSB\n");
194	goto out;
195	}
196	out:
197	mutex_unlock(&led->lock);
198	return ret;
199	}
200
201	static int lm3692x_init(struct lm3692x_led *led)
202	{
203	int ret;
204
205	if (led->regulator) {
206	ret = regulator_enable(led->regulator);
207	if (ret) {
208	dev_err(&led->client->dev,
209	"Failed to enable regulator\n");
210	return ret;
211	}
212	}
213
214	if (led->enable_gpio)
215	gpiod_direction_output(led->enable_gpio, 1);
216
217	ret = lm3692x_fault_check(led);
218	if (ret) {
219	dev_err(&led->client->dev, "Cannot read/clear faults\n");
220	goto out;
221	}
222
223	ret = regmap_write(led->regmap, LM3692X_BRT_CTRL, 0x00);
224	if (ret)
225	goto out;
226
227	/*
228	* For glitch free operation, the following data should
229	* only be written while device enable bit is 0
230	* per Section 7.5.14 of the data sheet
231	*/
232	ret = regmap_write(led->regmap, LM3692X_PWM_CTRL,
233	LM3692X_PWM_FILTER_100 \| LM3692X_PWM_SAMP_24MHZ);
234	if (ret)
235	goto out;
236
237	ret = regmap_write(led->regmap, LM3692X_BOOST_CTRL,
238	LM3692X_BRHT_MODE_RAMP_MULTI \|
239	LM3692X_BL_ADJ_POL \|
240	LM3692X_RAMP_RATE_250us);
241	if (ret)
242	goto out;
243
244	ret = regmap_write(led->regmap, LM3692X_AUTO_FREQ_HI, 0x00);
245	if (ret)
246	goto out;
247
248	ret = regmap_write(led->regmap, LM3692X_AUTO_FREQ_LO, 0x00);
249	if (ret)
250	goto out;
251
252	ret = regmap_write(led->regmap, LM3692X_BL_ADJ_THRESH, 0x00);
253	if (ret)
254	goto out;
255
256	ret = regmap_write(led->regmap, LM3692X_BRT_CTRL,
257	LM3692X_BL_ADJ_POL \| LM3692X_PWM_HYSTER_4LSB);
258	if (ret)
259	goto out;
260
261	return ret;
262	out:
263	dev_err(&led->client->dev, "Fail writing initialization values\n");
264
265	if (led->enable_gpio)
266	gpiod_direction_output(led->enable_gpio, 0);
267
268	if (led->regulator) {
269	ret = regulator_disable(led->regulator);
270	if (ret)
271	dev_err(&led->client->dev,
272	"Failed to disable regulator\n");
273	}
274
275	return ret;
276	}
277
278	static int lm3692x_probe(struct i2c_client *client,
279	const struct i2c_device_id *id)
280	{
281	int ret;
282	struct lm3692x_led *led;
283	struct device_node *np = client->dev.of_node;
284	struct device_node *child_node;
285	const char *name;
286
287	led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
288	if (!led)
289	return -ENOMEM;
290
291	for_each_available_child_of_node(np, child_node) {
292	led->led_dev.default_trigger = of_get_property(child_node,
293	"linux,default-trigger",
294	NULL);
295
296	ret = of_property_read_string(child_node, "label", &name);
297	if (!ret)
298	snprintf(led->label, sizeof(led->label),
299	"%s:%s", id->name, name);
300	else
301	snprintf(led->label, sizeof(led->label),
302	"%s::backlight_cluster", id->name);
303	};
304
305	led->enable_gpio = devm_gpiod_get_optional(&client->dev,
306	"enable", GPIOD_OUT_LOW);
307	if (IS_ERR(led->enable_gpio)) {
308	ret = PTR_ERR(led->enable_gpio);
309	dev_err(&client->dev, "Failed to get enable gpio: %d\n", ret);
310	return ret;
311	}
312
313	led->regulator = devm_regulator_get(&client->dev, "vled");
314	if (IS_ERR(led->regulator))
315	led->regulator = NULL;
316
317	led->client = client;
318	led->led_dev.name = led->label;
319	led->led_dev.brightness_set_blocking = lm3692x_brightness_set;
320
321	mutex_init(&led->lock);
322
323	i2c_set_clientdata(client, led);
324
325	led->regmap = devm_regmap_init_i2c(client, &lm3692x_regmap_config);
326	if (IS_ERR(led->regmap)) {
327	ret = PTR_ERR(led->regmap);
328	dev_err(&client->dev, "Failed to allocate register map: %d\n",
329	ret);
330	return ret;
331	}
332
333	ret = lm3692x_init(led);
334	if (ret)
335	return ret;
336
337	ret = devm_led_classdev_register(&client->dev, &led->led_dev);
338	if (ret) {
339	dev_err(&client->dev, "led register err: %d\n", ret);
340	return ret;
341	}
342
343	return 0;
344	}
345
346	static int lm3692x_remove(struct i2c_client *client)
347	{
348	struct lm3692x_led *led = i2c_get_clientdata(client);
349	int ret;
350
351	if (led->enable_gpio)
352	gpiod_direction_output(led->enable_gpio, 0);
353
354	if (led->regulator) {
355	ret = regulator_disable(led->regulator);
356	if (ret)
357	dev_err(&led->client->dev,
358	"Failed to disable regulator\n");
359	}
360
361	mutex_destroy(&led->lock);
362
363	return 0;
364	}
365
366	static const struct i2c_device_id lm3692x_id[] = {
367	{ "lm36922", 0 },
368	{ "lm36923", 1 },
369	{ }
370	};
371	MODULE_DEVICE_TABLE(i2c, lm3692x_id);
372
373	static const struct of_device_id of_lm3692x_leds_match[] = {
374	{ .compatible = "ti,lm36922", },
375	{ .compatible = "ti,lm36923", },
376	{},
377	};
378	MODULE_DEVICE_TABLE(of, of_lm3692x_leds_match);
379
380	static struct i2c_driver lm3692x_driver = {
381	.driver = {
382	.name = "lm3692x",
383	.of_match_table = of_lm3692x_leds_match,
384	},
385	.probe = lm3692x_probe,
386	.remove = lm3692x_remove,
387	.id_table = lm3692x_id,
388	};
389	module_i2c_driver(lm3692x_driver);
390
391	MODULE_DESCRIPTION("Texas Instruments LM3692X LED driver");
392	MODULE_AUTHOR("Dan Murphy <[email protected]>");
393	MODULE_LICENSE("GPL v2");