[linux-2.6-block.git] / drivers / leds / leds-lm3692x.c

// SPDX-License-Identifier: GPL-2.0
// TI LM3692x LED chip family driver
// Copyright (C) 2017-18 Texas Instruments Incorporated - http://www.ti.com/

#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 LM36922_MODEL	0
#define LM36923_MODEL	1

#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)
#define LM36923_LED3_EN		BIT(3)
#define LM3692X_ENABLE_MASK	(LM3692X_DEVICE_EN | LM3692X_LED1_EN | \
				 LM3692X_LED2_EN | LM36923_LED3_EN)

/* 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
 * @led_enable - LED sync to be enabled
 * @model_id - Current device model ID enumerated
 */
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];
	int led_enable;
	int model_id;
};

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 enable_state;
	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 LEDx enable bits are 0 and the device enable
	 * bit is set to 1.
	 * per Section 7.5.14 of the data sheet
	 */
	ret = regmap_write(led->regmap, LM3692X_EN, LM3692X_DEVICE_EN);
	if (ret)
		goto out;

	/* Set the brightness to 0 so when enabled the LEDs do not come
	 * on with full brightness.
	 */
	ret = regmap_write(led->regmap, LM3692X_BRT_MSB, 0);
	if (ret)
		goto out;

	ret = regmap_write(led->regmap, LM3692X_BRT_LSB, 0);
	if (ret)
		goto out;

	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;

	switch (led->led_enable) {
	case 0:
	default:
		if (led->model_id == LM36923_MODEL)
			enable_state = LM3692X_LED1_EN | LM3692X_LED2_EN |
			       LM36923_LED3_EN;
		else
			enable_state = LM3692X_LED1_EN | LM3692X_LED2_EN;

		break;
	case 1:
		enable_state = LM3692X_LED1_EN;
		break;
	case 2:
		enable_state = LM3692X_LED2_EN;
		break;

	case 3:
		if (led->model_id == LM36923_MODEL) {
			enable_state = LM36923_LED3_EN;
			break;
		}

		ret = -EINVAL;
		dev_err(&led->client->dev,
			"LED3 sync not available on this device\n");
		goto out;
	}

	ret = regmap_update_bits(led->regmap, LM3692X_EN, LM3692X_ENABLE_MASK,
				 enable_state | LM3692X_DEVICE_EN);

	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_dt(struct lm3692x_led *led)
{
	struct fwnode_handle *child = NULL;
	const char *name;
	int ret;

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

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

	child = device_get_next_child_node(&led->client->dev, child);
	if (!child) {
		dev_err(&led->client->dev, "No LED Child node\n");
		return -ENODEV;
	}

	fwnode_property_read_string(child, "linux,default-trigger",
				    &led->led_dev.default_trigger);

	ret = fwnode_property_read_string(child, "label", &name);
	if (ret)
		snprintf(led->label, sizeof(led->label),
			"%s::", led->client->name);
	else
		snprintf(led->label, sizeof(led->label),
			 "%s:%s", led->client->name, name);

	ret = fwnode_property_read_u32(child, "reg", &led->led_enable);
	if (ret) {
		dev_err(&led->client->dev, "reg DT property missing\n");
		return ret;
	}

	led->led_dev.name = led->label;

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

	led->led_dev.dev->of_node = to_of_node(child);

	return 0;
}

static int lm3692x_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	struct lm3692x_led *led;
	int ret;

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

	mutex_init(&led->lock);
	led->client = client;
	led->led_dev.brightness_set_blocking = lm3692x_brightness_set;
	led->model_id = id->driver_data;
	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_probe_dt(led);
	if (ret)
		return ret;

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

	return 0;
}

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

	ret = regmap_update_bits(led->regmap, LM3692X_EN, LM3692X_DEVICE_EN, 0);
	if (ret) {
		dev_err(&led->client->dev, "Failed to disable regulator\n");
		return 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", LM36922_MODEL },
	{ "lm36923", LM36923_MODEL },
	{ }
};
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 <dmurphy@ti.com>");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
43d20ff3 DM	1	// SPDX-License-Identifier: GPL-2.0
	2	// TI LM3692x LED chip family driver
	3	// Copyright (C) 2017-18 Texas Instruments Incorporated - http://www.ti.com/
9699cb6b DM	4
	5	#include <linux/gpio/consumer.h>
	6	#include <linux/i2c.h>
	7	#include <linux/init.h>
	8	#include <linux/leds.h>
	9	#include <linux/module.h>
	10	#include <linux/mutex.h>
	11	#include <linux/of.h>
	12	#include <linux/of_gpio.h>
	13	#include <linux/regmap.h>
	14	#include <linux/regulator/consumer.h>
	15	#include <linux/slab.h>
	16	#include <uapi/linux/uleds.h>
	17
07abd432 DM	18	#define LM36922_MODEL 0
	19	#define LM36923_MODEL 1
	20
9699cb6b DM	21	#define LM3692X_REV 0x0
	22	#define LM3692X_RESET 0x1
	23	#define LM3692X_EN 0x10
	24	#define LM3692X_BRT_CTRL 0x11
	25	#define LM3692X_PWM_CTRL 0x12
	26	#define LM3692X_BOOST_CTRL 0x13
	27	#define LM3692X_AUTO_FREQ_HI 0x15
	28	#define LM3692X_AUTO_FREQ_LO 0x16
	29	#define LM3692X_BL_ADJ_THRESH 0x17
	30	#define LM3692X_BRT_LSB 0x18
	31	#define LM3692X_BRT_MSB 0x19
	32	#define LM3692X_FAULT_CTRL 0x1e
	33	#define LM3692X_FAULT_FLAGS 0x1f
	34
	35	#define LM3692X_SW_RESET BIT(0)
	36	#define LM3692X_DEVICE_EN BIT(0)
	37	#define LM3692X_LED1_EN BIT(1)
	38	#define LM3692X_LED2_EN BIT(2)
07abd432 DM	39	#define LM36923_LED3_EN BIT(3)
	40	#define LM3692X_ENABLE_MASK (LM3692X_DEVICE_EN \| LM3692X_LED1_EN \| \
	41	LM3692X_LED2_EN \| LM36923_LED3_EN)
9699cb6b DM	42
	43	/* Brightness Control Bits */
	44	#define LM3692X_BL_ADJ_POL BIT(0)
	45	#define LM3692X_RAMP_RATE_125us 0x00
	46	#define LM3692X_RAMP_RATE_250us BIT(1)
	47	#define LM3692X_RAMP_RATE_500us BIT(2)
	48	#define LM3692X_RAMP_RATE_1ms (BIT(1) \| BIT(2))
	49	#define LM3692X_RAMP_RATE_2ms BIT(3)
	50	#define LM3692X_RAMP_RATE_4ms (BIT(3) \| BIT(1))
	51	#define LM3692X_RAMP_RATE_8ms (BIT(2) \| BIT(3))
	52	#define LM3692X_RAMP_RATE_16ms (BIT(1) \| BIT(2) \| BIT(3))
	53	#define LM3692X_RAMP_EN BIT(4)
	54	#define LM3692X_BRHT_MODE_REG 0x00
	55	#define LM3692X_BRHT_MODE_PWM BIT(5)
	56	#define LM3692X_BRHT_MODE_MULTI_RAMP BIT(6)
	57	#define LM3692X_BRHT_MODE_RAMP_MULTI (BIT(5) \| BIT(6))
	58	#define LM3692X_MAP_MODE_EXP BIT(7)
	59
	60	/* PWM Register Bits */
	61	#define LM3692X_PWM_FILTER_100 BIT(0)
	62	#define LM3692X_PWM_FILTER_150 BIT(1)
	63	#define LM3692X_PWM_FILTER_200 (BIT(0) \| BIT(1))
	64	#define LM3692X_PWM_HYSTER_1LSB BIT(2)
	65	#define LM3692X_PWM_HYSTER_2LSB BIT(3)
	66	#define LM3692X_PWM_HYSTER_3LSB (BIT(3) \| BIT(2))
	67	#define LM3692X_PWM_HYSTER_4LSB BIT(4)
	68	#define LM3692X_PWM_HYSTER_5LSB (BIT(4) \| BIT(2))
	69	#define LM3692X_PWM_HYSTER_6LSB (BIT(4) \| BIT(3))
	70	#define LM3692X_PWM_POLARITY BIT(5)
	71	#define LM3692X_PWM_SAMP_4MHZ BIT(6)
	72	#define LM3692X_PWM_SAMP_24MHZ BIT(7)
	73
	74	/* Boost Control Bits */
	75	#define LM3692X_OCP_PROT_1A BIT(0)
	76	#define LM3692X_OCP_PROT_1_25A BIT(1)
	77	#define LM3692X_OCP_PROT_1_5A (BIT(0) \| BIT(1))
	78	#define LM3692X_OVP_21V BIT(2)
	79	#define LM3692X_OVP_25V BIT(3)
	80	#define LM3692X_OVP_29V (BIT(2) \| BIT(3))
	81	#define LM3692X_MIN_IND_22UH BIT(4)
	82	#define LM3692X_BOOST_SW_1MHZ BIT(5)
	83	#define LM3692X_BOOST_SW_NO_SHIFT BIT(6)
	84
	85	/* Fault Control Bits */
	86	#define LM3692X_FAULT_CTRL_OVP BIT(0)
	87	#define LM3692X_FAULT_CTRL_OCP BIT(1)
	88	#define LM3692X_FAULT_CTRL_TSD BIT(2)
	89	#define LM3692X_FAULT_CTRL_OPEN BIT(3)
	90
	91	/* Fault Flag Bits */
	92	#define LM3692X_FAULT_FLAG_OVP BIT(0)
	93	#define LM3692X_FAULT_FLAG_OCP BIT(1)
	94	#define LM3692X_FAULT_FLAG_TSD BIT(2)
	95	#define LM3692X_FAULT_FLAG_SHRT BIT(3)
	96	#define LM3692X_FAULT_FLAG_OPEN BIT(4)
	97
	98	/**
	99	* struct lm3692x_led -
	100	* @lock - Lock for reading/writing the device
	101	* @client - Pointer to the I2C client
	102	* @led_dev - LED class device pointer
	103	* @regmap - Devices register map
	104	* @enable_gpio - VDDIO/EN gpio to enable communication interface
	105	* @regulator - LED supply regulator pointer
106	* @label - LED label
07abd432 DM	107	* @led_enable - LED sync to be enabled
07abd432 DM	108	* @model_id - Current device model ID enumerated
9699cb6b DM	109	*/
	110	struct lm3692x_led {
	111	struct mutex lock;
	112	struct i2c_client *client;
	113	struct led_classdev led_dev;
	114	struct regmap *regmap;
	115	struct gpio_desc *enable_gpio;
	116	struct regulator *regulator;
	117	char label[LED_MAX_NAME_SIZE];
07abd432 DM	118	int led_enable;
07abd432 DM	119	int model_id;
9699cb6b DM	120	};
	121
	122	static const struct reg_default lm3692x_reg_defs[] = {
	123	{LM3692X_EN, 0xf},
	124	{LM3692X_BRT_CTRL, 0x61},
	125	{LM3692X_PWM_CTRL, 0x73},
	126	{LM3692X_BOOST_CTRL, 0x6f},
	127	{LM3692X_AUTO_FREQ_HI, 0x0},
	128	{LM3692X_AUTO_FREQ_LO, 0x0},
	129	{LM3692X_BL_ADJ_THRESH, 0x0},
	130	{LM3692X_BRT_LSB, 0x7},
	131	{LM3692X_BRT_MSB, 0xff},
	132	{LM3692X_FAULT_CTRL, 0x7},
	133	};
	134
	135	static const struct regmap_config lm3692x_regmap_config = {
	136	.reg_bits = 8,
	137	.val_bits = 8,
	138
	139	.max_register = LM3692X_FAULT_FLAGS,
	140	.reg_defaults = lm3692x_reg_defs,
	141	.num_reg_defaults = ARRAY_SIZE(lm3692x_reg_defs),
	142	.cache_type = REGCACHE_RBTREE,
	143	};
	144
	145	static int lm3692x_fault_check(struct lm3692x_led *led)
	146	{
	147	int ret;
	148	unsigned int read_buf;
	149
	150	ret = regmap_read(led->regmap, LM3692X_FAULT_FLAGS, &read_buf);
	151	if (ret)
	152	return ret;
	153
	154	if (read_buf)
	155	dev_err(&led->client->dev, "Detected a fault 0x%X\n", read_buf);
	156
	157	/* The first read may clear the fault. Check again to see if the fault
	158	* still exits and return that value.
	159	*/
	160	regmap_read(led->regmap, LM3692X_FAULT_FLAGS, &read_buf);
	161	if (read_buf)
	162	dev_err(&led->client->dev, "Second read of fault flags 0x%X\n",
	163	read_buf);
	164
	165	return read_buf;
	166	}
	167
	168	static int lm3692x_brightness_set(struct led_classdev *led_cdev,
	169	enum led_brightness brt_val)
	170	{
	171	struct lm3692x_led *led =
	172	container_of(led_cdev, struct lm3692x_led, led_dev);
	173	int ret;
	174	int led_brightness_lsb = (brt_val >> 5);
	175
	176	mutex_lock(&led->lock);
	177
	178	ret = lm3692x_fault_check(led);
	179	if (ret) {
	180	dev_err(&led->client->dev, "Cannot read/clear faults\n");
	181	goto out;
	182	}
	183
184	ret = regmap_write(led->regmap, LM3692X_BRT_MSB, brt_val);
185	if (ret) {
186	dev_err(&led->client->dev, "Cannot write MSB\n");
187	goto out;
188	}
189
190	ret = regmap_write(led->regmap, LM3692X_BRT_LSB, led_brightness_lsb);
191	if (ret) {
192	dev_err(&led->client->dev, "Cannot write LSB\n");
193	goto out;
194	}
195	out:
196	mutex_unlock(&led->lock);
197	return ret;
198	}
199
200	static int lm3692x_init(struct lm3692x_led *led)
201	{
07abd432	202	int enable_state;
9699cb6b DM	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
07abd432 DM	229	* only be written while LEDx enable bits are 0 and the device enable
07abd432 DM	230	* bit is set to 1.
9699cb6b DM	231	* per Section 7.5.14 of the data sheet
9699cb6b DM	232	*/
07abd432 DM	233	ret = regmap_write(led->regmap, LM3692X_EN, LM3692X_DEVICE_EN);
	234	if (ret)
	235	goto out;
	236
	237	/* Set the brightness to 0 so when enabled the LEDs do not come
	238	* on with full brightness.
	239	*/
	240	ret = regmap_write(led->regmap, LM3692X_BRT_MSB, 0);
	241	if (ret)
	242	goto out;
	243
	244	ret = regmap_write(led->regmap, LM3692X_BRT_LSB, 0);
	245	if (ret)
	246	goto out;
	247
9699cb6b DM	248	ret = regmap_write(led->regmap, LM3692X_PWM_CTRL,
	249	LM3692X_PWM_FILTER_100 \| LM3692X_PWM_SAMP_24MHZ);
	250	if (ret)
	251	goto out;
	252
	253	ret = regmap_write(led->regmap, LM3692X_BOOST_CTRL,
	254	LM3692X_BRHT_MODE_RAMP_MULTI \|
	255	LM3692X_BL_ADJ_POL \|
	256	LM3692X_RAMP_RATE_250us);
	257	if (ret)
	258	goto out;
	259
	260	ret = regmap_write(led->regmap, LM3692X_AUTO_FREQ_HI, 0x00);
	261	if (ret)
	262	goto out;
	263
	264	ret = regmap_write(led->regmap, LM3692X_AUTO_FREQ_LO, 0x00);
	265	if (ret)
	266	goto out;
	267
	268	ret = regmap_write(led->regmap, LM3692X_BL_ADJ_THRESH, 0x00);
	269	if (ret)
	270	goto out;
	271
	272	ret = regmap_write(led->regmap, LM3692X_BRT_CTRL,
	273	LM3692X_BL_ADJ_POL \| LM3692X_PWM_HYSTER_4LSB);
	274	if (ret)
	275	goto out;
	276
07abd432 DM	277	switch (led->led_enable) {
	278	case 0:
	279	default:
	280	if (led->model_id == LM36923_MODEL)
	281	enable_state = LM3692X_LED1_EN \| LM3692X_LED2_EN \|
	282	LM36923_LED3_EN;
	283	else
	284	enable_state = LM3692X_LED1_EN \| LM3692X_LED2_EN;
	285
	286	break;
	287	case 1:
	288	enable_state = LM3692X_LED1_EN;
	289	break;
	290	case 2:
	291	enable_state = LM3692X_LED2_EN;
	292	break;
	293
	294	case 3:
	295	if (led->model_id == LM36923_MODEL) {
	296	enable_state = LM36923_LED3_EN;
	297	break;
	298	}
	299
	300	ret = -EINVAL;
	301	dev_err(&led->client->dev,
	302	"LED3 sync not available on this device\n");
	303	goto out;
	304	}
	305
	306	ret = regmap_update_bits(led->regmap, LM3692X_EN, LM3692X_ENABLE_MASK,
	307	enable_state \| LM3692X_DEVICE_EN);
	308
9699cb6b DM	309	return ret;
	310	out:
	311	dev_err(&led->client->dev, "Fail writing initialization values\n");
	312
	313	if (led->enable_gpio)
	314	gpiod_direction_output(led->enable_gpio, 0);
	315
	316	if (led->regulator) {
	317	ret = regulator_disable(led->regulator);
	318	if (ret)
	319	dev_err(&led->client->dev,
	320	"Failed to disable regulator\n");
	321	}
	322
	323	return ret;
	324	}
07abd432	325	static int lm3692x_probe_dt(struct lm3692x_led *led)
9699cb6b	326	{
9a5c1c64	327	struct fwnode_handle *child = NULL;
9699cb6b	328	const char *name;
9a5c1c64	329	int ret;
9699cb6b	330
07abd432	331	led->enable_gpio = devm_gpiod_get_optional(&led->client->dev,
9699cb6b DM	332	"enable", GPIOD_OUT_LOW);
	333	if (IS_ERR(led->enable_gpio)) {
	334	ret = PTR_ERR(led->enable_gpio);
07abd432 DM	335	dev_err(&led->client->dev, "Failed to get enable gpio: %d\n",
07abd432 DM	336	ret);
9699cb6b DM	337	return ret;
	338	}
	339
07abd432	340	led->regulator = devm_regulator_get(&led->client->dev, "vled");
9699cb6b DM	341	if (IS_ERR(led->regulator))
	342	led->regulator = NULL;
	343
9a5c1c64 DM	344	child = device_get_next_child_node(&led->client->dev, child);
	345	if (!child) {
	346	dev_err(&led->client->dev, "No LED Child node\n");
07abd432	347	return -ENODEV;
9a5c1c64 DM	348	}
	349
	350	fwnode_property_read_string(child, "linux,default-trigger",
	351	&led->led_dev.default_trigger);
	352
	353	ret = fwnode_property_read_string(child, "label", &name);
	354	if (ret)
	355	snprintf(led->label, sizeof(led->label),
	356	"%s::", led->client->name);
	357	else
	358	snprintf(led->label, sizeof(led->label),
	359	"%s:%s", led->client->name, name);
	360
07abd432 DM	361	ret = fwnode_property_read_u32(child, "reg", &led->led_enable);
	362	if (ret) {
	363	dev_err(&led->client->dev, "reg DT property missing\n");
	364	return ret;
	365	}
	366
	367	led->led_dev.name = led->label;
9a5c1c64	368
07abd432	369	ret = devm_led_classdev_register(&led->client->dev, &led->led_dev);
9699cb6b	370	if (ret) {
07abd432 DM	371	dev_err(&led->client->dev, "led register err: %d\n", ret);
	372	return ret;
	373	}
	374
	375	led->led_dev.dev->of_node = to_of_node(child);
	376
	377	return 0;
	378	}
	379
	380	static int lm3692x_probe(struct i2c_client *client,
	381	const struct i2c_device_id *id)
	382	{
	383	struct lm3692x_led *led;
	384	int ret;
	385
	386	led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
	387	if (!led)
	388	return -ENOMEM;
	389
	390	mutex_init(&led->lock);
	391	led->client = client;
	392	led->led_dev.brightness_set_blocking = lm3692x_brightness_set;
	393	led->model_id = id->driver_data;
	394	i2c_set_clientdata(client, led);
	395
	396	led->regmap = devm_regmap_init_i2c(client, &lm3692x_regmap_config);
	397	if (IS_ERR(led->regmap)) {
	398	ret = PTR_ERR(led->regmap);
	399	dev_err(&client->dev, "Failed to allocate register map: %d\n",
	400	ret);
9699cb6b DM	401	return ret;
	402	}
	403
07abd432 DM	404	ret = lm3692x_probe_dt(led);
	405	if (ret)
	406	return ret;
	407
	408	ret = lm3692x_init(led);
	409	if (ret)
	410	return ret;
	411
9699cb6b DM	412	return 0;
	413	}
	414
	415	static int lm3692x_remove(struct i2c_client *client)
	416	{
	417	struct lm3692x_led *led = i2c_get_clientdata(client);
	418	int ret;
	419
07abd432 DM	420	ret = regmap_update_bits(led->regmap, LM3692X_EN, LM3692X_DEVICE_EN, 0);
	421	if (ret) {
	422	dev_err(&led->client->dev, "Failed to disable regulator\n");
	423	return ret;
	424	}
	425
9699cb6b DM	426	if (led->enable_gpio)
	427	gpiod_direction_output(led->enable_gpio, 0);
	428
	429	if (led->regulator) {
	430	ret = regulator_disable(led->regulator);
	431	if (ret)
	432	dev_err(&led->client->dev,
	433	"Failed to disable regulator\n");
	434	}
	435
	436	mutex_destroy(&led->lock);
	437
	438	return 0;
	439	}
	440
	441	static const struct i2c_device_id lm3692x_id[] = {
07abd432 DM	442	{ "lm36922", LM36922_MODEL },
07abd432 DM	443	{ "lm36923", LM36923_MODEL },
9699cb6b DM	444	{ }
	445	};
	446	MODULE_DEVICE_TABLE(i2c, lm3692x_id);
	447
	448	static const struct of_device_id of_lm3692x_leds_match[] = {
	449	{ .compatible = "ti,lm36922", },
	450	{ .compatible = "ti,lm36923", },
	451	{},
	452	};
	453	MODULE_DEVICE_TABLE(of, of_lm3692x_leds_match);
	454
	455	static struct i2c_driver lm3692x_driver = {
	456	.driver = {
	457	.name = "lm3692x",
	458	.of_match_table = of_lm3692x_leds_match,
	459	},
	460	.probe = lm3692x_probe,
	461	.remove = lm3692x_remove,
	462	.id_table = lm3692x_id,
	463	};
	464	module_i2c_driver(lm3692x_driver);
	465
	466	MODULE_DESCRIPTION("Texas Instruments LM3692X LED driver");
	467	MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
	468	MODULE_LICENSE("GPL v2");