diff mbox series

[v4,2/2] leds: lm3692x: Introduce LM3692x dual string driver

Message ID 20171128204021.12699-2-dmurphy@ti.com
State Superseded
Headers show
Series [v4,1/2] dt: bindings: lm3692x: Add bindings for lm3692x LED driver | expand

Commit Message

Dan Murphy Nov. 28, 2017, 8:40 p.m. UTC
Introducing the LM3692x Dual-String white LED driver.

Data sheet is located
http://www.ti.com/lit/ds/snvsa29/snvsa29.pdf

Signed-off-by: Dan Murphy <dmurphy@ti.com>

---
v4 - Converted to devm led class register, changed MODULE_LICENSE to GPL v2, 
set the led name based on child node name or label entry, removed fault and
returned read_buf for fault checking, added mutex_destroy to remove function,
and removed LED_FULL - https://patchwork.kernel.org/patch/10060109/

v3 - Add missing Makefile and Kconfig from v1 and v2 - https://patchwork.kernel.org/patch/10060075/
v2 - Added data sheet link, fixed linuxdoc format, returned on failure in init
routine, return on fault_check failure, updated brightness calculation and
fixed capitalization issue - https://patchwork.kernel.org/patch/10056675/

 drivers/leds/Kconfig        |   7 +
 drivers/leds/Makefile       |   1 +
 drivers/leds/leds-lm3692x.c | 382 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 390 insertions(+)
 create mode 100644 drivers/leds/leds-lm3692x.c

-- 
2.15.0.124.g7668cbc60

Comments

Dan Murphy Nov. 30, 2017, 7:22 p.m. UTC | #1
Jacek

Thanks for the review

On 11/29/2017 03:52 PM, Jacek Anaszewski wrote:
> Hi Dan,

> 

> Thanks for the update.

> 

> On 11/28/2017 09:40 PM, Dan Murphy wrote:

>> Introducing the LM3692x Dual-String white LED driver.

>>

>> Data sheet is located

>> http://www.ti.com/lit/ds/snvsa29/snvsa29.pdf

>>

>> Signed-off-by: Dan Murphy <dmurphy@ti.com>

>> ---

>> v4 - Converted to devm led class register, changed MODULE_LICENSE to GPL v2, 

>> set the led name based on child node name or label entry, removed fault and

>> returned read_buf for fault checking, added mutex_destroy to remove function,

>> and removed LED_FULL - https://patchwork.kernel.org/patch/10060109/

>>

>> v3 - Add missing Makefile and Kconfig from v1 and v2 - https://patchwork.kernel.org/patch/10060075/

>> v2 - Added data sheet link, fixed linuxdoc format, returned on failure in init

>> routine, return on fault_check failure, updated brightness calculation and

>> fixed capitalization issue - https://patchwork.kernel.org/patch/10056675/

>>

>>  drivers/leds/Kconfig        |   7 +

>>  drivers/leds/Makefile       |   1 +

>>  drivers/leds/leds-lm3692x.c | 382 ++++++++++++++++++++++++++++++++++++++++++++

>>  3 files changed, 390 insertions(+)

>>  create mode 100644 drivers/leds/leds-lm3692x.c

>>

>> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig

>> index 318a28fd58fe..c0583f1bc8ea 100644

>> --- a/drivers/leds/Kconfig

>> +++ b/drivers/leds/Kconfig

>> @@ -137,6 +137,13 @@ config LEDS_LM3642

>>  	  converter plus 1.5A constant current driver for a high-current

>>  	  white LED.

>>  

>> +config LEDS_LM3692X

>> +	tristate "LED support for LM3692x Chips"

>> +	depends on LEDS_CLASS && I2C

>> +	select REGMAP_I2C

>> +	help

>> +	  This option enables support for the TI LM3692x family

>> +	  of white LED string drivers used for backlighting.

>>  

>>  config LEDS_LOCOMO

>>  	tristate "LED Support for Locomo device"

>> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile

>> index a2a6b5a4f86d..987884a5b9a5 100644

>> --- a/drivers/leds/Makefile

>> +++ b/drivers/leds/Makefile

>> @@ -74,6 +74,7 @@ obj-$(CONFIG_LEDS_PM8058)		+= leds-pm8058.o

>>  obj-$(CONFIG_LEDS_MLXCPLD)		+= leds-mlxcpld.o

>>  obj-$(CONFIG_LEDS_NIC78BX)		+= leds-nic78bx.o

>>  obj-$(CONFIG_LEDS_MT6323)		+= leds-mt6323.o

>> +obj-$(CONFIG_LEDS_LM3692X)		+= leds-lm3692x.o

>>  

>>  # LED SPI Drivers

>>  obj-$(CONFIG_LEDS_DAC124S085)		+= leds-dac124s085.o

>> diff --git a/drivers/leds/leds-lm3692x.c b/drivers/leds/leds-lm3692x.c

>> new file mode 100644

>> index 000000000000..fcf0573fb985

>> --- /dev/null

>> +++ b/drivers/leds/leds-lm3692x.c

>> @@ -0,0 +1,382 @@

>> +/*

>> + * TI lm3692x LED Driver

>> + *

>> + * Copyright (C) 2017 Texas Instruments

>> + *

>> + * Author: Dan Murphy <dmurphy@ti.com>

>> + *

>> + * 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/i2c.h>

>> +#include <linux/init.h>

>> +#include <linux/leds.h>

>> +#include <linux/regmap.h>

>> +#include <linux/regulator/consumer.h>

>> +#include <linux/module.h>

>> +#include <linux/mutex.h>

>> +#include <linux/of.h>

>> +#include <linux/of_gpio.h>

>> +#include <linux/gpio/consumer.h>

>> +#include <linux/slab.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

> 

> s/led class/LED class/

> 


ACK

>> + * @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;

>> +	const char *label;

>> +};

>> +

>> +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);

>> +

>> +	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;

>> +

>> +	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.name = of_get_property(child_node, "label", NULL) ? :

>> +						 child_node->name;

> 

> You need also devicename segment in the LED class device name.

> You can take it from the parent node name. Please follow what has been

> done for drivers/leds/leds-as3645a.c, with a reservation that your

> DT binding is correct, as it doesn't contain devicename segment,

> which turned out to be against DT specification. So you'll need

> to tweak a bit leds-as3645a.c way of composing LED class device

> name to take devicename from parent DT node also for the case

> when DT label property is present.

> 

> I will be convenient to create some generic LED core function

> for composing LED class device name basing on DT data.

> 

> All these findings are quite recent, that's why there is no

> well established approach to the problem.

> 


ACK

>> +

>> +		led->led_dev.default_trigger = of_get_property(child_node,

>> +						    "linux,default-trigger",

>> +						    NULL);

>> +	};

>> +

>> +	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.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;

>> +

>> +	led_classdev_unregister(&led->led_dev);

> 

> You don't need it if registering with devm* API.

> 


ACK

>> +

>> +	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);

>> +

>> +#ifdef CONFIG_OF

> 

> We seem to entirely rely on OF.

> Let's drop this guard and add OF dependency to Kconfig.

> 


ACK

>> +static const struct of_device_id of_lm3692x_leds_match[] = {

>> +	{ .compatible = "ti,lm36922", },

>> +	{ .compatible = "ti,lm36923", },

>> +	{},

>> +};

>> +MODULE_DEVICE_TABLE(of, of_lm3692x_leds_match);

>> +#endif

>> +

>> +static struct i2c_driver lm3692x_driver = {

>> +	.driver = {

>> +		.name	= "lm3692x",

>> +		.of_match_table = of_match_ptr(of_lm3692x_leds_match),

> 

> Also of_match_ptr() will be redundant then.

> 


ACK

>> +	},

>> +	.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");

>>

> 



-- 
------------------
Dan Murphy
diff mbox series

Patch

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 318a28fd58fe..c0583f1bc8ea 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -137,6 +137,13 @@  config LEDS_LM3642
 	  converter plus 1.5A constant current driver for a high-current
 	  white LED.
 
+config LEDS_LM3692X
+	tristate "LED support for LM3692x Chips"
+	depends on LEDS_CLASS && I2C
+	select REGMAP_I2C
+	help
+	  This option enables support for the TI LM3692x family
+	  of white LED string drivers used for backlighting.
 
 config LEDS_LOCOMO
 	tristate "LED Support for Locomo device"
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index a2a6b5a4f86d..987884a5b9a5 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -74,6 +74,7 @@  obj-$(CONFIG_LEDS_PM8058)		+= leds-pm8058.o
 obj-$(CONFIG_LEDS_MLXCPLD)		+= leds-mlxcpld.o
 obj-$(CONFIG_LEDS_NIC78BX)		+= leds-nic78bx.o
 obj-$(CONFIG_LEDS_MT6323)		+= leds-mt6323.o
+obj-$(CONFIG_LEDS_LM3692X)		+= leds-lm3692x.o
 
 # LED SPI Drivers
 obj-$(CONFIG_LEDS_DAC124S085)		+= leds-dac124s085.o
diff --git a/drivers/leds/leds-lm3692x.c b/drivers/leds/leds-lm3692x.c
new file mode 100644
index 000000000000..fcf0573fb985
--- /dev/null
+++ b/drivers/leds/leds-lm3692x.c
@@ -0,0 +1,382 @@ 
+/*
+ * TI lm3692x LED Driver
+ *
+ * Copyright (C) 2017 Texas Instruments
+ *
+ * Author: Dan Murphy <dmurphy@ti.com>
+ *
+ * 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/i2c.h>
+#include <linux/init.h>
+#include <linux/leds.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/gpio/consumer.h>
+#include <linux/slab.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;
+	const char *label;
+};
+
+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);
+
+	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;
+
+	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.name = of_get_property(child_node, "label", NULL) ? :
+						 child_node->name;
+
+		led->led_dev.default_trigger = of_get_property(child_node,
+						    "linux,default-trigger",
+						    NULL);
+	};
+
+	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.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;
+
+	led_classdev_unregister(&led->led_dev);
+
+	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);
+
+#ifdef CONFIG_OF
+static const struct of_device_id of_lm3692x_leds_match[] = {
+	{ .compatible = "ti,lm36922", },
+	{ .compatible = "ti,lm36923", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, of_lm3692x_leds_match);
+#endif
+
+static struct i2c_driver lm3692x_driver = {
+	.driver = {
+		.name	= "lm3692x",
+		.of_match_table = of_match_ptr(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");