[v4,4/4] leds: lm3532: Introduce the lm3532 LED driver
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Message ID 20190313123249.17258-4-dmurphy@ti.com
State New, archived
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Series
  • [v4,1/4] dt: lm3532: Add lm3532 dt doc and update ti_lmu doc
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Commit Message

Dan Murphy March 13, 2019, 12:32 p.m. UTC
Introduce the Texas Instruments LM3532 White LED driver.
The driver supports ALS configurability or manual brightness
control.

The driver also supports associating LED strings with specific
control banks in a group or as individually controlled strings.

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

v4 - Updated code to DT doc changes appending "ti," to TI specific properties -
https://lore.kernel.org/patchwork/patch/1050124/

v3 - Removed switch case for register setting in favor of an algorithim (v1 comment),
https://lore.kernel.org/patchwork/patch/1049024/
v2 - Added look up tables for als_avg, als_imp and ramp times, fixed brightness
control when ALS is in control, added property value checks to ensure the values
are not out of bounds - https://lore.kernel.org/patchwork/patch/1048807/

 drivers/leds/Kconfig       |  10 +
 drivers/leds/Makefile      |   1 +
 drivers/leds/leds-lm3532.c | 681 +++++++++++++++++++++++++++++++++++++
 3 files changed, 692 insertions(+)
 create mode 100644 drivers/leds/leds-lm3532.c

Comments

Dan Murphy March 20, 2019, 12:39 p.m. UTC | #1
Hello

On 3/13/19 7:32 AM, Dan Murphy wrote:
> Introduce the Texas Instruments LM3532 White LED driver.
> The driver supports ALS configurability or manual brightness
> control.
> 
> The driver also supports associating LED strings with specific
> control banks in a group or as individually controlled strings.
> 

I have a v5 series ready for posting and only the DT was reviewed.

Do we have any comments on the code?

Dan

> Signed-off-by: Dan Murphy <dmurphy@ti.com>
> ---
> 
> v4 - Updated code to DT doc changes appending "ti," to TI specific properties -
> https://lore.kernel.org/patchwork/patch/1050124/
> 
> v3 - Removed switch case for register setting in favor of an algorithim (v1 comment),
> https://lore.kernel.org/patchwork/patch/1049024/
> v2 - Added look up tables for als_avg, als_imp and ramp times, fixed brightness
> control when ALS is in control, added property value checks to ensure the values
> are not out of bounds - https://lore.kernel.org/patchwork/patch/1048807/
> 
>  drivers/leds/Kconfig       |  10 +
>  drivers/leds/Makefile      |   1 +
>  drivers/leds/leds-lm3532.c | 681 +++++++++++++++++++++++++++++++++++++
>  3 files changed, 692 insertions(+)
>  create mode 100644 drivers/leds/leds-lm3532.c
> 
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index a72f97fca57b..da00b9ed5a5c 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -138,6 +138,16 @@ config LEDS_LM3530
>  	  controlled manually or using PWM input or using ambient
>  	  light automatically.
>  
> +config LEDS_LM3532
> +	tristate "LCD Backlight driver for LM3532"
> +	depends on LEDS_CLASS
> +	depends on I2C
> +	help
> +	  This option enables support for the LCD backlight using
> +	  LM3532 ambient light sensor chip. This ALS chip can be
> +	  controlled manually or using PWM input or using ambient
> +	  light automatically.
> +
>  config LEDS_LM3533
>  	tristate "LED support for LM3533"
>  	depends on LEDS_CLASS
> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
> index 4c1b0054f379..7a8b1f55d459 100644
> --- a/drivers/leds/Makefile
> +++ b/drivers/leds/Makefile
> @@ -18,6 +18,7 @@ obj-$(CONFIG_LEDS_BD2802)		+= leds-bd2802.o
>  obj-$(CONFIG_LEDS_CPCAP)		+= leds-cpcap.o
>  obj-$(CONFIG_LEDS_LOCOMO)		+= leds-locomo.o
>  obj-$(CONFIG_LEDS_LM3530)		+= leds-lm3530.o
> +obj-$(CONFIG_LEDS_LM3532)		+= leds-lm3532.o
>  obj-$(CONFIG_LEDS_LM3533)		+= leds-lm3533.o
>  obj-$(CONFIG_LEDS_LM3642)		+= leds-lm3642.o
>  obj-$(CONFIG_LEDS_MIKROTIK_RB532)	+= leds-rb532.o
> diff --git a/drivers/leds/leds-lm3532.c b/drivers/leds/leds-lm3532.c
> new file mode 100644
> index 000000000000..e8a614d71469
> --- /dev/null
> +++ b/drivers/leds/leds-lm3532.c
> @@ -0,0 +1,681 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// TI LM3532 LED driver
> +// Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/
> +
> +#include <linux/i2c.h>
> +#include <linux/leds.h>
> +#include <linux/slab.h>
> +#include <linux/regmap.h>
> +#include <linux/types.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/module.h>
> +#include <uapi/linux/uleds.h>
> +#include <linux/gpio/consumer.h>
> +
> +#define LM3532_NAME "lm3532-led"
> +#define LM3532_BL_MODE_MANUAL	0x00
> +#define LM3532_BL_MODE_ALS	0x01
> +
> +#define LM3532_REG_OUTPUT_CFG	0x10
> +#define LM3532_REG_STARTSHUT_RAMP	0x11
> +#define LM3532_REG_RT_RAMP	0x12
> +#define LM3532_REG_PWM_A_CFG	0x13
> +#define LM3532_REG_PWM_B_CFG	0x14
> +#define LM3532_REG_PWM_C_CFG	0x15
> +#define LM3532_REG_ZONE_CFG_A	0x16
> +#define LM3532_REG_CTRL_A_BRT	0x17
> +#define LM3532_REG_ZONE_CFG_B	0x18
> +#define LM3532_REG_CTRL_B_BRT	0x19
> +#define LM3532_REG_ZONE_CFG_C	0x1a
> +#define LM3532_REG_CTRL_C_BRT	0x1b
> +#define LM3532_REG_ENABLE	0x1d
> +#define LM3532_ALS_CONFIG	0x23
> +#define LM3532_REG_ZN_0_HI	0x60
> +#define LM3532_REG_ZN_0_LO	0x61
> +#define LM3532_REG_ZN_1_HI	0x62
> +#define LM3532_REG_ZN_1_LO	0x63
> +#define LM3532_REG_ZN_2_HI	0x64
> +#define LM3532_REG_ZN_2_LO	0x65
> +#define LM3532_REG_ZN_3_HI	0x66
> +#define LM3532_REG_ZN_3_LO	0x67
> +#define LM3532_REG_MAX		0x7e
> +
> +/* Contorl Enable */
> +#define LM3532_CTRL_A_ENABLE	BIT(0)
> +#define LM3532_CTRL_B_ENABLE	BIT(1)
> +#define LM3532_CTRL_C_ENABLE	BIT(2)
> +
> +/* PWM Zone Control */
> +#define LM3532_PWM_ZONE_MASK	0x7c
> +#define LM3532_PWM_ZONE_0_EN	BIT(2)
> +#define LM3532_PWM_ZONE_1_EN	BIT(3)
> +#define LM3532_PWM_ZONE_2_EN	BIT(4)
> +#define LM3532_PWM_ZONE_3_EN	BIT(5)
> +#define LM3532_PWM_ZONE_4_EN	BIT(6)
> +
> +/* Brightness Configuration */
> +#define LM3532_I2C_CTRL		BIT(0)
> +#define LM3532_ALS_CTRL		0
> +#define LM3532_LINEAR_MAP	BIT(1)
> +#define LM3532_ZONE_MASK	(BIT(2) | BIT(3) | BIT(4))
> +#define LM3532_ZONE_0		0
> +#define LM3532_ZONE_1		BIT(2)
> +#define LM3532_ZONE_2		BIT(3)
> +#define LM3532_ZONE_3		(BIT(2) | BIT(3))
> +#define LM3532_ZONE_4		BIT(4)
> +
> +#define LM3532_ENABLE_ALS	BIT(3)
> +#define LM3532_ALS_SEL_SHIFT	6
> +
> +/* Zone Boundary Register */
> +#define LM3532_ALS_WINDOW_mV	2000
> +#define LM3532_ALS_ZB_MAX	4
> +#define LM3532_ALS_OFFSET_mV	2
> +
> +#define LM3532_CONTROL_A	0
> +#define LM3532_CONTROL_B	1
> +#define LM3532_CONTROL_C	2
> +#define LM3532_MAX_CONTROL_BANKS 3
> +#define LM3532_MAX_LED_STRINGS	3
> +
> +#define LM3532_OUTPUT_CFG_MASK	0x3
> +#define LM3532_BRT_VAL_ADJUST	8
> +#define LM3532_RAMP_DOWN_SHIFT	3
> +
> +#define LM3532_NUM_RAMP_VALS	8
> +#define LM3532_NUM_AVG_VALS	8
> +#define LM3532_NUM_IMP_VALS	32
> +
> +/*
> + * struct lm3532_als_data
> + * @config - value of ALS configuration register
> + * @als1_imp_sel - value of ALS1 resistor select register
> + * @als2_imp_sel - value of ALS2 resistor select register
> + * @als_avrg_time - ALS averaging time
> + * @als_input_mode - ALS input mode for brightness control
> + * @als_vmin - Minimum ALS voltage
> + * @als_vmax - Maximum ALS voltage
> + * @zone_lo - values of ALS lo ZB(Zone Boundary) registers
> + * @zone_hi - values of ALS hi ZB(Zone Boundary) registers
> + */
> +struct lm3532_als_data {
> +	u8 config;
> +	u8 als1_imp_sel;
> +	u8 als2_imp_sel;
> +	u8 als_avrg_time;
> +	u8 als_input_mode;
> +	u32 als_vmin;
> +	u32 als_vmax;
> +	u8 zones_lo[LM3532_ALS_ZB_MAX];
> +	u8 zones_hi[LM3532_ALS_ZB_MAX];
> +};
> +
> +/**
> + * struct lm3532_led
> + * @led_dev: led class device
> + * @priv - Pointer the device data structure
> + * @control_bank - Control bank the LED is associated to
> + * @mode - Mode of the LED string
> + * @num_leds - Number of LED strings are supported in this array
> + * @led_strings - The LED strings supported in this array
> + * @label - LED label
> + */
> +struct lm3532_led {
> +	struct led_classdev led_dev;
> +	struct lm3532_data *priv;
> +
> +	int control_bank;
> +	int mode;
> +	int num_leds;
> +	u32 led_strings[LM3532_MAX_CONTROL_BANKS];
> +	char label[LED_MAX_NAME_SIZE];
> +};
> +
> +/**
> + * struct lm3532_data
> + * @enable_gpio - Hardware enable gpio
> + * @regulator: regulator
> + * @client: i2c client
> + * @regmap - Devices register map
> + * @dev - Pointer to the devices device struct
> + * @lock - Lock for reading/writing the device
> + * @als_data - Pointer to the als data struct
> + * @runtime_ramp_up - Runtime ramp up setting
> + * @runtime_ramp_down - Runtime ramp down setting
> + * @leds - Array of LED strings
> + */
> +struct lm3532_data {
> +	struct gpio_desc *enable_gpio;
> +	struct regulator *regulator;
> +	struct i2c_client *client;
> +	struct regmap *regmap;
> +	struct device *dev;
> +	struct mutex lock;
> +
> +	struct lm3532_als_data *als_data;
> +
> +	u32 runtime_ramp_up;
> +	u32 runtime_ramp_down;
> +
> +	struct lm3532_led leds[];
> +};
> +
> +static const struct reg_default lm3532_reg_defs[] = {
> +	{LM3532_REG_OUTPUT_CFG, 0xe4},
> +	{LM3532_REG_STARTSHUT_RAMP, 0xc0},
> +	{LM3532_REG_RT_RAMP, 0xc0},
> +	{LM3532_REG_PWM_A_CFG, 0x82},
> +	{LM3532_REG_PWM_B_CFG, 0x82},
> +	{LM3532_REG_PWM_C_CFG, 0x82},
> +	{LM3532_REG_ZONE_CFG_A, 0xf1},
> +	{LM3532_REG_CTRL_A_BRT, 0xf3},
> +	{LM3532_REG_ZONE_CFG_B, 0xf1},
> +	{LM3532_REG_CTRL_B_BRT, 0xf3},
> +	{LM3532_REG_ZONE_CFG_C, 0xf1},
> +	{LM3532_REG_CTRL_C_BRT, 0xf3},
> +	{LM3532_REG_ENABLE, 0xf8},
> +	{LM3532_ALS_CONFIG, 0x44},
> +	{LM3532_REG_ZN_0_HI, 0x35},
> +	{LM3532_REG_ZN_0_LO, 0x33},
> +	{LM3532_REG_ZN_1_HI, 0x6a},
> +	{LM3532_REG_ZN_1_LO, 0x66},
> +	{LM3532_REG_ZN_2_HI, 0xa1},
> +	{LM3532_REG_ZN_2_LO, 0x99},
> +	{LM3532_REG_ZN_3_HI, 0xdc},
> +	{LM3532_REG_ZN_3_LO, 0xcc},
> +};
> +
> +static const struct regmap_config lm3532_regmap_config = {
> +	.reg_bits = 8,
> +	.val_bits = 8,
> +
> +	.max_register = LM3532_REG_MAX,
> +	.reg_defaults = lm3532_reg_defs,
> +	.num_reg_defaults = ARRAY_SIZE(lm3532_reg_defs),
> +	.cache_type = REGCACHE_FLAT,
> +};
> +
> +const static int als_imp_table[LM3532_NUM_IMP_VALS] = {37000, 18500, 12330,
> +						       92500, 7400, 6170, 5290,
> +						       4630, 4110, 3700, 3360,
> +						       3080, 2850, 2640, 2440,
> +						       2310, 2180, 2060, 1950,
> +						       1850, 1760, 1680, 1610,
> +						       1540, 1480, 1420, 1370,
> +						       1320, 1280, 1230, 1190};
> +static int lm3532_get_als_imp_index(int als_imped)
> +{
> +	int i;
> +
> +	if (als_imped > als_imp_table[1])
> +		return 0;
> +
> +	if (als_imped < als_imp_table[LM3532_NUM_IMP_VALS - 1])
> +		return LM3532_NUM_IMP_VALS - 1;
> +
> +	for (i = 1; i < LM3532_NUM_IMP_VALS; i++) {
> +		if (als_imped == als_imp_table[i])
> +			return i;
> +
> +		/* Find an approximate index by looking up the table */
> +		if (als_imped < als_imp_table[i - 1] &&
> +		    als_imped > als_imp_table[i]) {
> +			if (als_imped - als_imp_table[i - 1] <
> +			    als_imp_table[i] - als_imped)
> +				return i + 1;
> +			else
> +				return i;
> +		}
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int lm3532_get_index(const int table[], int size, int value)
> +{
> +	int i;
> +
> +	for (i = 1; i < size; i++) {
> +		if (value == table[i])
> +			return i;
> +
> +		/* Find an approximate index by looking up the table */
> +		if (value > table[i - 1] &&
> +		    value < table[i]) {
> +			if (value - table[i - 1] < table[i] - value)
> +				return i - 1;
> +			else
> +				return i;
> +		}
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +const static int als_avrg_table[LM3532_NUM_AVG_VALS] = {17920, 35840, 71680,
> +							1433360, 286720, 573440,
> +							1146880, 2293760};
> +static int lm3532_get_als_avg_index(int avg_time)
> +{
> +	if (avg_time <= als_avrg_table[0])
> +		return 0;
> +
> +	if (avg_time > als_avrg_table[LM3532_NUM_AVG_VALS - 1])
> +		return LM3532_NUM_AVG_VALS - 1;
> +
> +	return lm3532_get_index(&als_avrg_table[0], LM3532_NUM_AVG_VALS,
> +				avg_time);
> +}
> +
> +const static int ramp_table[LM3532_NUM_RAMP_VALS] = { 8, 1024, 2048, 4096, 8192,
> +						     16384, 32768, 65536};
> +static int lm3532_get_ramp_index(int ramp_time)
> +{
> +	if (ramp_time <= ramp_table[0])
> +		return 0;
> +
> +	if (ramp_time > ramp_table[LM3532_NUM_RAMP_VALS - 1])
> +		return LM3532_NUM_RAMP_VALS - 1;
> +
> +	return lm3532_get_index(&ramp_table[0], LM3532_NUM_RAMP_VALS,
> +				ramp_time);
> +}
> +
> +static int lm3532_led_enable(struct lm3532_led *led_data)
> +{
> +	int ctrl_en_val = BIT(led_data->control_bank);
> +	int ret;
> +
> +	ret = regmap_update_bits(led_data->priv->regmap, LM3532_REG_ENABLE,
> +					 ctrl_en_val, ctrl_en_val);
> +	if (ret) {
> +		dev_err(led_data->priv->dev, "Failed to set ctrl:%d\n", ret);
> +		return ret;
> +	}
> +
> +	return regulator_enable(led_data->priv->regulator);
> +}
> +
> +static int lm3532_led_disable(struct lm3532_led *led_data)
> +{
> +	int ctrl_en_val = BIT(led_data->control_bank);
> +	int ret;
> +
> +	ret = regmap_update_bits(led_data->priv->regmap, LM3532_REG_ENABLE,
> +					 ctrl_en_val, ~ctrl_en_val);
> +	if (ret) {
> +		dev_err(led_data->priv->dev, "Failed to set ctrl:%d\n", ret);
> +		return ret;
> +	}
> +
> +	return regulator_disable(led_data->priv->regulator);
> +}
> +
> +static int lm3532_brightness_set(struct led_classdev *led_cdev,
> +				 enum led_brightness brt_val)
> +{
> +	struct lm3532_led *led =
> +			container_of(led_cdev, struct lm3532_led, led_dev);
> +	u8 brightness_reg;
> +	int ret;
> +
> +	mutex_lock(&led->priv->lock);
> +
> +	if (led->mode == LM3532_BL_MODE_ALS) {
> +		if (brt_val > LED_OFF)
> +			ret = lm3532_led_enable(led);
> +		else
> +			ret = lm3532_led_disable(led);
> +
> +		goto unlock;
> +	}
> +
> +	if (brt_val == LED_OFF) {
> +		ret = lm3532_led_disable(led);
> +		goto unlock;
> +	}
> +
> +	ret = lm3532_led_enable(led);
> +	if (ret)
> +		goto unlock;
> +
> +	brightness_reg = LM3532_REG_CTRL_A_BRT + led->control_bank * 2;
> +	brt_val = brt_val / LM3532_BRT_VAL_ADJUST;
> +
> +	ret = regmap_write(led->priv->regmap, brightness_reg, brt_val);
> +
> +unlock:
> +	mutex_unlock(&led->priv->lock);
> +	return ret;
> +}
> +
> +static int lm3532_init_registers(struct lm3532_led *led)
> +{
> +	struct lm3532_data *drvdata = led->priv;
> +	unsigned int runtime_ramp_val;
> +	unsigned int output_cfg_val = 0;
> +	unsigned int output_cfg_shift = 0;
> +	unsigned int output_cfg_mask = 0;
> +	int ret, i;
> +
> +	for (i = 0; i < led->num_leds; i++) {
> +		output_cfg_shift = led->led_strings[i] * 2;
> +		output_cfg_val |= (led->control_bank << output_cfg_shift);
> +		output_cfg_mask |= LM3532_OUTPUT_CFG_MASK << output_cfg_shift;
> +	}
> +
> +	ret = regmap_update_bits(drvdata->regmap, LM3532_REG_OUTPUT_CFG,
> +				 output_cfg_mask, output_cfg_val);
> +	if (ret)
> +		return ret;
> +
> +	runtime_ramp_val = drvdata->runtime_ramp_up |
> +			 (drvdata->runtime_ramp_down << LM3532_RAMP_DOWN_SHIFT);
> +
> +	return regmap_write(drvdata->regmap, LM3532_REG_RT_RAMP,
> +			    runtime_ramp_val);
> +}
> +
> +static int lm3532_als_configure(struct lm3532_data *priv,
> +				struct lm3532_led *led)
> +{
> +	struct lm3532_als_data *als = priv->als_data;
> +	u32 als_vmin, als_vmax, als_vstep;
> +	int zone_reg = LM3532_REG_ZN_0_HI;
> +	int brightnes_config_reg;
> +	int ret;
> +	int i;
> +
> +	als_vmin = als->als_vmin;
> +	als_vmax = als->als_vmax;
> +
> +	als_vstep = (als_vmax - als_vmin) / ((LM3532_ALS_ZB_MAX + 1) * 2);
> +
> +	for (i = 0; i < LM3532_ALS_ZB_MAX; i++) {
> +		als->zones_lo[i] = ((als_vmin + als_vstep + (i * als_vstep)) *
> +				LED_FULL) / 1000;
> +		als->zones_hi[i] = ((als_vmin + LM3532_ALS_OFFSET_mV +
> +				als_vstep + (i * als_vstep)) * LED_FULL) / 1000;
> +
> +		zone_reg = LM3532_REG_ZN_0_HI + i * 2;
> +		ret = regmap_write(priv->regmap, zone_reg, als->zones_lo[i]);
> +		if (ret)
> +			return ret;
> +
> +		zone_reg += 1;
> +		ret = regmap_write(priv->regmap, zone_reg, als->zones_hi[i]);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	als->config = (als->als_avrg_time | (LM3532_ENABLE_ALS) |
> +		(als->als_input_mode << LM3532_ALS_SEL_SHIFT));
> +
> +	ret = regmap_write(priv->regmap, LM3532_ALS_CONFIG, als->config);
> +	if (ret)
> +		return ret;
> +
> +	brightnes_config_reg = LM3532_REG_ZONE_CFG_A + led->control_bank * 2;
> +
> +	return regmap_update_bits(priv->regmap, brightnes_config_reg,
> +				  LM3532_I2C_CTRL, LM3532_ALS_CTRL);
> +}
> +
> +static int lm3532_parse_als(struct lm3532_data *priv)
> +{
> +	struct lm3532_als_data *als;
> +	int als_avg_time;
> +	int als_impedance;
> +	int ret;
> +
> +	als = devm_kzalloc(priv->dev, sizeof(*als), GFP_KERNEL);
> +	if (als == NULL)
> +		return -ENOMEM;
> +
> +	ret = device_property_read_u32(&priv->client->dev, "ti,als-vmin",
> +				       &als->als_vmin);
> +	if (ret)
> +		als->als_vmin = 0;
> +
> +	ret = device_property_read_u32(&priv->client->dev, "ti,als-vmax",
> +				       &als->als_vmax);
> +	if (ret)
> +		als->als_vmax = LM3532_ALS_WINDOW_mV;
> +
> +	if (als->als_vmax > LM3532_ALS_WINDOW_mV) {
> +		ret = -EINVAL;
> +		return ret;
> +	}
> +
> +	ret = device_property_read_u32(&priv->client->dev, "ti,als1-imp-sel",
> +				      &als_impedance);
> +	if (ret)
> +		als->als1_imp_sel = 0;
> +	else
> +		als->als1_imp_sel = lm3532_get_als_imp_index(als_impedance);
> +
> +	ret = device_property_read_u32(&priv->client->dev, "ti,als2-imp-sel",
> +				      &als_impedance);
> +	if (ret)
> +		als->als2_imp_sel = 0;
> +	else
> +		als->als2_imp_sel = lm3532_get_als_imp_index(als_impedance);
> +
> +	ret = device_property_read_u32(&priv->client->dev, "ti,als-avrg-time-us",
> +				      &als_avg_time);
> +	if (ret)
> +		als->als_avrg_time = 0;
> +	else
> +		als->als_avrg_time = lm3532_get_als_avg_index(als_avg_time);
> +
> +	ret = device_property_read_u8(&priv->client->dev, "ti,als-input-mode",
> +				      &als->als_input_mode);
> +	if (ret)
> +		als->als_input_mode = 0;
> +
> +	if (als->als_input_mode > LM3532_BL_MODE_ALS) {
> +		ret = -EINVAL;
> +		return ret;
> +	}
> +
> +	priv->als_data = als;
> +
> +	return ret;
> +}
> +
> +static int lm3532_parse_node(struct lm3532_data *priv)
> +{
> +	struct fwnode_handle *child = NULL;
> +	struct lm3532_led *led;
> +	const char *name;
> +	int control_bank;
> +	u32 ramp_time;
> +	size_t i = 0;
> +	int ret;
> +
> +	priv->enable_gpio = devm_gpiod_get_optional(&priv->client->dev,
> +						   "enable", GPIOD_OUT_LOW);
> +	if (IS_ERR(priv->enable_gpio))
> +		priv->enable_gpio = NULL;
> +
> +	priv->regulator = devm_regulator_get(&priv->client->dev, "vin");
> +	if (IS_ERR(priv->regulator))
> +		priv->regulator = NULL;
> +
> +	ret = device_property_read_u32(&priv->client->dev, "ramp-up-us",
> +				       &ramp_time);
> +	if (ret)
> +		dev_info(&priv->client->dev, "ramp-up-ms property missing\n");
> +	else
> +		priv->runtime_ramp_up = lm3532_get_ramp_index(ramp_time);
> +
> +	ret = device_property_read_u32(&priv->client->dev, "ramp-down-us",
> +				       &ramp_time);
> +	if (ret)
> +		dev_info(&priv->client->dev, "ramp-down-ms property missing\n");
> +	else
> +		priv->runtime_ramp_down = lm3532_get_ramp_index(ramp_time);
> +
> +	device_for_each_child_node(priv->dev, child) {
> +		led = &priv->leds[i];
> +
> +		ret = fwnode_property_read_u32(child, "reg", &control_bank);
> +		if (ret) {
> +			dev_err(&priv->client->dev, "reg property missing\n");
> +			fwnode_handle_put(child);
> +			goto child_out;
> +		}
> +
> +		if (control_bank > LM3532_CONTROL_C) {
> +			dev_err(&priv->client->dev, "Control bank invalid\n");
> +			continue;
> +		}
> +
> +		led->control_bank = control_bank;
> +
> +		ret = fwnode_property_read_u32(child, "ti,led-mode",
> +					       &led->mode);
> +		if (ret) {
> +			dev_err(&priv->client->dev, "ti,led-mode property missing\n");
> +			fwnode_handle_put(child);
> +			goto child_out;
> +		}
> +
> +		if (led->mode == LM3532_BL_MODE_ALS) {
> +			ret = lm3532_parse_als(priv);
> +			if (ret)
> +				dev_err(&priv->client->dev, "Failed to parse als\n");
> +			else
> +				lm3532_als_configure(priv, led);
> +		}
> +
> +		led->num_leds = fwnode_property_read_u32_array(child,
> +							       "led-sources",
> +							       NULL, 0);
> +
> +		if (led->num_leds > LM3532_MAX_LED_STRINGS) {
> +			dev_err(&priv->client->dev, "To many LED string defined\n");
> +			continue;
> +		}
> +
> +		ret = fwnode_property_read_u32_array(child, "led-sources",
> +						    led->led_strings,
> +						    led->num_leds);
> +		if (ret) {
> +			dev_err(&priv->client->dev, "led-sources property missing\n");
> +			fwnode_handle_put(child);
> +			goto child_out;
> +		}
> +
> +		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::", priv->client->name);
> +		else
> +			snprintf(led->label, sizeof(led->label),
> +				 "%s:%s", priv->client->name, name);
> +
> +		led->priv = priv;
> +		led->led_dev.name = led->label;
> +		led->led_dev.brightness_set_blocking = lm3532_brightness_set;
> +
> +		ret = devm_led_classdev_register(priv->dev, &led->led_dev);
> +		if (ret) {
> +			dev_err(&priv->client->dev, "led register err: %d\n",
> +				ret);
> +			fwnode_handle_put(child);
> +			goto child_out;
> +		}
> +
> +		lm3532_init_registers(led);
> +
> +		i++;
> +	}
> +
> +child_out:
> +	return ret;
> +}
> +
> +static int lm3532_probe(struct i2c_client *client,
> +			   const struct i2c_device_id *id)
> +{
> +	struct lm3532_data *drvdata;
> +	int ret = 0;
> +	int count;
> +
> +	count = device_get_child_node_count(&client->dev);
> +	if (!count) {
> +		dev_err(&client->dev, "LEDs are not defined in device tree!");
> +		return -ENODEV;
> +	}
> +
> +	drvdata = devm_kzalloc(&client->dev, struct_size(drvdata, leds, count),
> +			   GFP_KERNEL);
> +	if (drvdata == NULL)
> +		return -ENOMEM;
> +
> +	drvdata->client = client;
> +	drvdata->dev = &client->dev;
> +
> +	drvdata->regmap = devm_regmap_init_i2c(client, &lm3532_regmap_config);
> +	if (IS_ERR(drvdata->regmap)) {
> +		ret = PTR_ERR(drvdata->regmap);
> +		dev_err(&client->dev, "Failed to allocate register map: %d\n",
> +			ret);
> +		return ret;
> +	}
> +
> +	mutex_init(&drvdata->lock);
> +	i2c_set_clientdata(client, drvdata);
> +
> +	ret = lm3532_parse_node(drvdata);
> +	if (ret) {
> +		dev_err(&client->dev, "Failed to parse node\n");
> +		return ret;
> +	}
> +
> +	if (drvdata->enable_gpio)
> +		gpiod_direction_output(drvdata->enable_gpio, 1);
> +
> +	return ret;
> +}
> +
> +static int lm3532_remove(struct i2c_client *client)
> +{
> +	struct lm3532_data *drvdata = i2c_get_clientdata(client);
> +
> +	if (drvdata->enable_gpio)
> +		gpiod_direction_output(drvdata->enable_gpio, 0);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id of_lm3532_leds_match[] = {
> +	{ .compatible = "ti,lm3532", },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, of_lm3532_leds_match);
> +
> +static const struct i2c_device_id lm3532_id[] = {
> +	{LM3532_NAME, 0},
> +	{}
> +};
> +MODULE_DEVICE_TABLE(i2c, lm3532_id);
> +
> +static struct i2c_driver lm3532_i2c_driver = {
> +	.probe = lm3532_probe,
> +	.remove = lm3532_remove,
> +	.id_table = lm3532_id,
> +	.driver = {
> +		.name = LM3532_NAME,
> +		.of_match_table = of_lm3532_leds_match,
> +	},
> +};
> +module_i2c_driver(lm3532_i2c_driver);
> +
> +MODULE_DESCRIPTION("Back Light driver for LM3532");
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
>
Jacek Anaszewski March 20, 2019, 6:59 p.m. UTC | #2
Hi Dan,

I have one minor issue below.

On 3/13/19 1:32 PM, Dan Murphy wrote:
> Introduce the Texas Instruments LM3532 White LED driver.
> The driver supports ALS configurability or manual brightness
> control.
> 
> The driver also supports associating LED strings with specific
> control banks in a group or as individually controlled strings.
> 
> Signed-off-by: Dan Murphy <dmurphy@ti.com>
> ---
> 
> v4 - Updated code to DT doc changes appending "ti," to TI specific properties -
> https://lore.kernel.org/patchwork/patch/1050124/
> 
> v3 - Removed switch case for register setting in favor of an algorithim (v1 comment),
> https://lore.kernel.org/patchwork/patch/1049024/
> v2 - Added look up tables for als_avg, als_imp and ramp times, fixed brightness
> control when ALS is in control, added property value checks to ensure the values
> are not out of bounds - https://lore.kernel.org/patchwork/patch/1048807/
> 
>   drivers/leds/Kconfig       |  10 +
>   drivers/leds/Makefile      |   1 +
>   drivers/leds/leds-lm3532.c | 681 +++++++++++++++++++++++++++++++++++++
>   3 files changed, 692 insertions(+)
>   create mode 100644 drivers/leds/leds-lm3532.c
> 
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index a72f97fca57b..da00b9ed5a5c 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -138,6 +138,16 @@ config LEDS_LM3530
>   	  controlled manually or using PWM input or using ambient
>   	  light automatically.
>   
> +config LEDS_LM3532
> +	tristate "LCD Backlight driver for LM3532"
> +	depends on LEDS_CLASS
> +	depends on I2C
> +	help
> +	  This option enables support for the LCD backlight using
> +	  LM3532 ambient light sensor chip. This ALS chip can be
> +	  controlled manually or using PWM input or using ambient
> +	  light automatically.
> +
>   config LEDS_LM3533
>   	tristate "LED support for LM3533"
>   	depends on LEDS_CLASS
> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
> index 4c1b0054f379..7a8b1f55d459 100644
> --- a/drivers/leds/Makefile
> +++ b/drivers/leds/Makefile
> @@ -18,6 +18,7 @@ obj-$(CONFIG_LEDS_BD2802)		+= leds-bd2802.o
>   obj-$(CONFIG_LEDS_CPCAP)		+= leds-cpcap.o
>   obj-$(CONFIG_LEDS_LOCOMO)		+= leds-locomo.o
>   obj-$(CONFIG_LEDS_LM3530)		+= leds-lm3530.o
> +obj-$(CONFIG_LEDS_LM3532)		+= leds-lm3532.o
>   obj-$(CONFIG_LEDS_LM3533)		+= leds-lm3533.o
>   obj-$(CONFIG_LEDS_LM3642)		+= leds-lm3642.o
>   obj-$(CONFIG_LEDS_MIKROTIK_RB532)	+= leds-rb532.o
> diff --git a/drivers/leds/leds-lm3532.c b/drivers/leds/leds-lm3532.c
> new file mode 100644
> index 000000000000..e8a614d71469
> --- /dev/null
> +++ b/drivers/leds/leds-lm3532.c
> @@ -0,0 +1,681 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// TI LM3532 LED driver
> +// Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/
> +
> +#include <linux/i2c.h>
> +#include <linux/leds.h>
> +#include <linux/slab.h>
> +#include <linux/regmap.h>
> +#include <linux/types.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/module.h>
> +#include <uapi/linux/uleds.h>
> +#include <linux/gpio/consumer.h>
> +
> +#define LM3532_NAME "lm3532-led"
> +#define LM3532_BL_MODE_MANUAL	0x00
> +#define LM3532_BL_MODE_ALS	0x01
> +
> +#define LM3532_REG_OUTPUT_CFG	0x10
> +#define LM3532_REG_STARTSHUT_RAMP	0x11
> +#define LM3532_REG_RT_RAMP	0x12
> +#define LM3532_REG_PWM_A_CFG	0x13
> +#define LM3532_REG_PWM_B_CFG	0x14
> +#define LM3532_REG_PWM_C_CFG	0x15
> +#define LM3532_REG_ZONE_CFG_A	0x16
> +#define LM3532_REG_CTRL_A_BRT	0x17
> +#define LM3532_REG_ZONE_CFG_B	0x18
> +#define LM3532_REG_CTRL_B_BRT	0x19
> +#define LM3532_REG_ZONE_CFG_C	0x1a
> +#define LM3532_REG_CTRL_C_BRT	0x1b
> +#define LM3532_REG_ENABLE	0x1d
> +#define LM3532_ALS_CONFIG	0x23
> +#define LM3532_REG_ZN_0_HI	0x60
> +#define LM3532_REG_ZN_0_LO	0x61
> +#define LM3532_REG_ZN_1_HI	0x62
> +#define LM3532_REG_ZN_1_LO	0x63
> +#define LM3532_REG_ZN_2_HI	0x64
> +#define LM3532_REG_ZN_2_LO	0x65
> +#define LM3532_REG_ZN_3_HI	0x66
> +#define LM3532_REG_ZN_3_LO	0x67
> +#define LM3532_REG_MAX		0x7e
> +
> +/* Contorl Enable */
> +#define LM3532_CTRL_A_ENABLE	BIT(0)
> +#define LM3532_CTRL_B_ENABLE	BIT(1)
> +#define LM3532_CTRL_C_ENABLE	BIT(2)
> +
> +/* PWM Zone Control */
> +#define LM3532_PWM_ZONE_MASK	0x7c
> +#define LM3532_PWM_ZONE_0_EN	BIT(2)
> +#define LM3532_PWM_ZONE_1_EN	BIT(3)
> +#define LM3532_PWM_ZONE_2_EN	BIT(4)
> +#define LM3532_PWM_ZONE_3_EN	BIT(5)
> +#define LM3532_PWM_ZONE_4_EN	BIT(6)
> +
> +/* Brightness Configuration */
> +#define LM3532_I2C_CTRL		BIT(0)
> +#define LM3532_ALS_CTRL		0
> +#define LM3532_LINEAR_MAP	BIT(1)
> +#define LM3532_ZONE_MASK	(BIT(2) | BIT(3) | BIT(4))
> +#define LM3532_ZONE_0		0
> +#define LM3532_ZONE_1		BIT(2)
> +#define LM3532_ZONE_2		BIT(3)
> +#define LM3532_ZONE_3		(BIT(2) | BIT(3))
> +#define LM3532_ZONE_4		BIT(4)
> +
> +#define LM3532_ENABLE_ALS	BIT(3)
> +#define LM3532_ALS_SEL_SHIFT	6
> +
> +/* Zone Boundary Register */
> +#define LM3532_ALS_WINDOW_mV	2000
> +#define LM3532_ALS_ZB_MAX	4
> +#define LM3532_ALS_OFFSET_mV	2
> +
> +#define LM3532_CONTROL_A	0
> +#define LM3532_CONTROL_B	1
> +#define LM3532_CONTROL_C	2
> +#define LM3532_MAX_CONTROL_BANKS 3
> +#define LM3532_MAX_LED_STRINGS	3
> +
> +#define LM3532_OUTPUT_CFG_MASK	0x3
> +#define LM3532_BRT_VAL_ADJUST	8
> +#define LM3532_RAMP_DOWN_SHIFT	3
> +
> +#define LM3532_NUM_RAMP_VALS	8
> +#define LM3532_NUM_AVG_VALS	8
> +#define LM3532_NUM_IMP_VALS	32
> +
> +/*
> + * struct lm3532_als_data
> + * @config - value of ALS configuration register
> + * @als1_imp_sel - value of ALS1 resistor select register
> + * @als2_imp_sel - value of ALS2 resistor select register
> + * @als_avrg_time - ALS averaging time
> + * @als_input_mode - ALS input mode for brightness control
> + * @als_vmin - Minimum ALS voltage
> + * @als_vmax - Maximum ALS voltage
> + * @zone_lo - values of ALS lo ZB(Zone Boundary) registers
> + * @zone_hi - values of ALS hi ZB(Zone Boundary) registers
> + */
> +struct lm3532_als_data {
> +	u8 config;
> +	u8 als1_imp_sel;
> +	u8 als2_imp_sel;
> +	u8 als_avrg_time;
> +	u8 als_input_mode;
> +	u32 als_vmin;
> +	u32 als_vmax;
> +	u8 zones_lo[LM3532_ALS_ZB_MAX];
> +	u8 zones_hi[LM3532_ALS_ZB_MAX];
> +};
> +
> +/**
> + * struct lm3532_led
> + * @led_dev: led class device
> + * @priv - Pointer the device data structure
> + * @control_bank - Control bank the LED is associated to
> + * @mode - Mode of the LED string
> + * @num_leds - Number of LED strings are supported in this array
> + * @led_strings - The LED strings supported in this array
> + * @label - LED label
> + */
> +struct lm3532_led {
> +	struct led_classdev led_dev;
> +	struct lm3532_data *priv;
> +
> +	int control_bank;
> +	int mode;
> +	int num_leds;
> +	u32 led_strings[LM3532_MAX_CONTROL_BANKS];
> +	char label[LED_MAX_NAME_SIZE];
> +};
> +
> +/**
> + * struct lm3532_data
> + * @enable_gpio - Hardware enable gpio
> + * @regulator: regulator
> + * @client: i2c client
> + * @regmap - Devices register map
> + * @dev - Pointer to the devices device struct
> + * @lock - Lock for reading/writing the device
> + * @als_data - Pointer to the als data struct
> + * @runtime_ramp_up - Runtime ramp up setting
> + * @runtime_ramp_down - Runtime ramp down setting
> + * @leds - Array of LED strings
> + */
> +struct lm3532_data {
> +	struct gpio_desc *enable_gpio;
> +	struct regulator *regulator;
> +	struct i2c_client *client;
> +	struct regmap *regmap;
> +	struct device *dev;
> +	struct mutex lock;
> +
> +	struct lm3532_als_data *als_data;
> +
> +	u32 runtime_ramp_up;
> +	u32 runtime_ramp_down;
> +
> +	struct lm3532_led leds[];
> +};
> +
> +static const struct reg_default lm3532_reg_defs[] = {
> +	{LM3532_REG_OUTPUT_CFG, 0xe4},
> +	{LM3532_REG_STARTSHUT_RAMP, 0xc0},
> +	{LM3532_REG_RT_RAMP, 0xc0},
> +	{LM3532_REG_PWM_A_CFG, 0x82},
> +	{LM3532_REG_PWM_B_CFG, 0x82},
> +	{LM3532_REG_PWM_C_CFG, 0x82},
> +	{LM3532_REG_ZONE_CFG_A, 0xf1},
> +	{LM3532_REG_CTRL_A_BRT, 0xf3},
> +	{LM3532_REG_ZONE_CFG_B, 0xf1},
> +	{LM3532_REG_CTRL_B_BRT, 0xf3},
> +	{LM3532_REG_ZONE_CFG_C, 0xf1},
> +	{LM3532_REG_CTRL_C_BRT, 0xf3},
> +	{LM3532_REG_ENABLE, 0xf8},
> +	{LM3532_ALS_CONFIG, 0x44},
> +	{LM3532_REG_ZN_0_HI, 0x35},
> +	{LM3532_REG_ZN_0_LO, 0x33},
> +	{LM3532_REG_ZN_1_HI, 0x6a},
> +	{LM3532_REG_ZN_1_LO, 0x66},
> +	{LM3532_REG_ZN_2_HI, 0xa1},
> +	{LM3532_REG_ZN_2_LO, 0x99},
> +	{LM3532_REG_ZN_3_HI, 0xdc},
> +	{LM3532_REG_ZN_3_LO, 0xcc},
> +};
> +
> +static const struct regmap_config lm3532_regmap_config = {
> +	.reg_bits = 8,
> +	.val_bits = 8,
> +
> +	.max_register = LM3532_REG_MAX,
> +	.reg_defaults = lm3532_reg_defs,
> +	.num_reg_defaults = ARRAY_SIZE(lm3532_reg_defs),
> +	.cache_type = REGCACHE_FLAT,
> +};
> +
> +const static int als_imp_table[LM3532_NUM_IMP_VALS] = {37000, 18500, 12330,
> +						       92500, 7400, 6170, 5290,
> +						       4630, 4110, 3700, 3360,
> +						       3080, 2850, 2640, 2440,
> +						       2310, 2180, 2060, 1950,
> +						       1850, 1760, 1680, 1610,
> +						       1540, 1480, 1420, 1370,
> +						       1320, 1280, 1230, 1190};
> +static int lm3532_get_als_imp_index(int als_imped)
> +{
> +	int i;
> +
> +	if (als_imped > als_imp_table[1])
> +		return 0;
> +
> +	if (als_imped < als_imp_table[LM3532_NUM_IMP_VALS - 1])
> +		return LM3532_NUM_IMP_VALS - 1;
> +
> +	for (i = 1; i < LM3532_NUM_IMP_VALS; i++) {
> +		if (als_imped == als_imp_table[i])
> +			return i;
> +
> +		/* Find an approximate index by looking up the table */
> +		if (als_imped < als_imp_table[i - 1] &&
> +		    als_imped > als_imp_table[i]) {
> +			if (als_imped - als_imp_table[i - 1] <
> +			    als_imp_table[i] - als_imped)
> +				return i + 1;
> +			else
> +				return i;
> +		}
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int lm3532_get_index(const int table[], int size, int value)
> +{
> +	int i;
> +
> +	for (i = 1; i < size; i++) {
> +		if (value == table[i])
> +			return i;
> +
> +		/* Find an approximate index by looking up the table */
> +		if (value > table[i - 1] &&
> +		    value < table[i]) {
> +			if (value - table[i - 1] < table[i] - value)
> +				return i - 1;
> +			else
> +				return i;
> +		}
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +const static int als_avrg_table[LM3532_NUM_AVG_VALS] = {17920, 35840, 71680,
> +							1433360, 286720, 573440,
> +							1146880, 2293760};
> +static int lm3532_get_als_avg_index(int avg_time)
> +{
> +	if (avg_time <= als_avrg_table[0])
> +		return 0;
> +
> +	if (avg_time > als_avrg_table[LM3532_NUM_AVG_VALS - 1])
> +		return LM3532_NUM_AVG_VALS - 1;
> +
> +	return lm3532_get_index(&als_avrg_table[0], LM3532_NUM_AVG_VALS,
> +				avg_time);
> +}
> +
> +const static int ramp_table[LM3532_NUM_RAMP_VALS] = { 8, 1024, 2048, 4096, 8192,
> +						     16384, 32768, 65536};
> +static int lm3532_get_ramp_index(int ramp_time)
> +{
> +	if (ramp_time <= ramp_table[0])
> +		return 0;
> +
> +	if (ramp_time > ramp_table[LM3532_NUM_RAMP_VALS - 1])
> +		return LM3532_NUM_RAMP_VALS - 1;
> +
> +	return lm3532_get_index(&ramp_table[0], LM3532_NUM_RAMP_VALS,
> +				ramp_time);
> +}
> +
> +static int lm3532_led_enable(struct lm3532_led *led_data)
> +{
> +	int ctrl_en_val = BIT(led_data->control_bank);
> +	int ret;
> +
> +	ret = regmap_update_bits(led_data->priv->regmap, LM3532_REG_ENABLE,
> +					 ctrl_en_val, ctrl_en_val);
> +	if (ret) {
> +		dev_err(led_data->priv->dev, "Failed to set ctrl:%d\n", ret);
> +		return ret;
> +	}
> +
> +	return regulator_enable(led_data->priv->regulator);
> +}
> +
> +static int lm3532_led_disable(struct lm3532_led *led_data)
> +{
> +	int ctrl_en_val = BIT(led_data->control_bank);
> +	int ret;
> +
> +	ret = regmap_update_bits(led_data->priv->regmap, LM3532_REG_ENABLE,
> +					 ctrl_en_val, ~ctrl_en_val);
> +	if (ret) {
> +		dev_err(led_data->priv->dev, "Failed to set ctrl:%d\n", ret);
> +		return ret;
> +	}
> +
> +	return regulator_disable(led_data->priv->regulator);
> +}
> +
> +static int lm3532_brightness_set(struct led_classdev *led_cdev,
> +				 enum led_brightness brt_val)
> +{
> +	struct lm3532_led *led =
> +			container_of(led_cdev, struct lm3532_led, led_dev);
> +	u8 brightness_reg;
> +	int ret;
> +
> +	mutex_lock(&led->priv->lock);
> +
> +	if (led->mode == LM3532_BL_MODE_ALS) {
> +		if (brt_val > LED_OFF)
> +			ret = lm3532_led_enable(led);
> +		else
> +			ret = lm3532_led_disable(led);
> +
> +		goto unlock;
> +	}
> +
> +	if (brt_val == LED_OFF) {
> +		ret = lm3532_led_disable(led);
> +		goto unlock;
> +	}
> +
> +	ret = lm3532_led_enable(led);
> +	if (ret)
> +		goto unlock;
> +
> +	brightness_reg = LM3532_REG_CTRL_A_BRT + led->control_bank * 2;
> +	brt_val = brt_val / LM3532_BRT_VAL_ADJUST;
> +
> +	ret = regmap_write(led->priv->regmap, brightness_reg, brt_val);
> +
> +unlock:
> +	mutex_unlock(&led->priv->lock);
> +	return ret;
> +}
> +
> +static int lm3532_init_registers(struct lm3532_led *led)
> +{
> +	struct lm3532_data *drvdata = led->priv;
> +	unsigned int runtime_ramp_val;
> +	unsigned int output_cfg_val = 0;
> +	unsigned int output_cfg_shift = 0;
> +	unsigned int output_cfg_mask = 0;
> +	int ret, i;
> +
> +	for (i = 0; i < led->num_leds; i++) {
> +		output_cfg_shift = led->led_strings[i] * 2;
> +		output_cfg_val |= (led->control_bank << output_cfg_shift);
> +		output_cfg_mask |= LM3532_OUTPUT_CFG_MASK << output_cfg_shift;
> +	}
> +
> +	ret = regmap_update_bits(drvdata->regmap, LM3532_REG_OUTPUT_CFG,
> +				 output_cfg_mask, output_cfg_val);
> +	if (ret)
> +		return ret;
> +
> +	runtime_ramp_val = drvdata->runtime_ramp_up |
> +			 (drvdata->runtime_ramp_down << LM3532_RAMP_DOWN_SHIFT);
> +
> +	return regmap_write(drvdata->regmap, LM3532_REG_RT_RAMP,
> +			    runtime_ramp_val);
> +}
> +
> +static int lm3532_als_configure(struct lm3532_data *priv,
> +				struct lm3532_led *led)
> +{
> +	struct lm3532_als_data *als = priv->als_data;
> +	u32 als_vmin, als_vmax, als_vstep;
> +	int zone_reg = LM3532_REG_ZN_0_HI;
> +	int brightnes_config_reg;
> +	int ret;
> +	int i;
> +
> +	als_vmin = als->als_vmin;
> +	als_vmax = als->als_vmax;
> +
> +	als_vstep = (als_vmax - als_vmin) / ((LM3532_ALS_ZB_MAX + 1) * 2);
> +
> +	for (i = 0; i < LM3532_ALS_ZB_MAX; i++) {
> +		als->zones_lo[i] = ((als_vmin + als_vstep + (i * als_vstep)) *
> +				LED_FULL) / 1000;
> +		als->zones_hi[i] = ((als_vmin + LM3532_ALS_OFFSET_mV +
> +				als_vstep + (i * als_vstep)) * LED_FULL) / 1000;
> +
> +		zone_reg = LM3532_REG_ZN_0_HI + i * 2;
> +		ret = regmap_write(priv->regmap, zone_reg, als->zones_lo[i]);
> +		if (ret)
> +			return ret;
> +
> +		zone_reg += 1;
> +		ret = regmap_write(priv->regmap, zone_reg, als->zones_hi[i]);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	als->config = (als->als_avrg_time | (LM3532_ENABLE_ALS) |
> +		(als->als_input_mode << LM3532_ALS_SEL_SHIFT));
> +
> +	ret = regmap_write(priv->regmap, LM3532_ALS_CONFIG, als->config);
> +	if (ret)
> +		return ret;
> +
> +	brightnes_config_reg = LM3532_REG_ZONE_CFG_A + led->control_bank * 2;
> +
> +	return regmap_update_bits(priv->regmap, brightnes_config_reg,
> +				  LM3532_I2C_CTRL, LM3532_ALS_CTRL);
> +}
> +
> +static int lm3532_parse_als(struct lm3532_data *priv)
> +{
> +	struct lm3532_als_data *als;
> +	int als_avg_time;
> +	int als_impedance;
> +	int ret;
> +
> +	als = devm_kzalloc(priv->dev, sizeof(*als), GFP_KERNEL);
> +	if (als == NULL)
> +		return -ENOMEM;
> +
> +	ret = device_property_read_u32(&priv->client->dev, "ti,als-vmin",
> +				       &als->als_vmin);
> +	if (ret)
> +		als->als_vmin = 0;
> +
> +	ret = device_property_read_u32(&priv->client->dev, "ti,als-vmax",
> +				       &als->als_vmax);
> +	if (ret)
> +		als->als_vmax = LM3532_ALS_WINDOW_mV;
> +
> +	if (als->als_vmax > LM3532_ALS_WINDOW_mV) {
> +		ret = -EINVAL;
> +		return ret;
> +	}
> +
> +	ret = device_property_read_u32(&priv->client->dev, "ti,als1-imp-sel",
> +				      &als_impedance);
> +	if (ret)
> +		als->als1_imp_sel = 0;
> +	else
> +		als->als1_imp_sel = lm3532_get_als_imp_index(als_impedance);
> +
> +	ret = device_property_read_u32(&priv->client->dev, "ti,als2-imp-sel",
> +				      &als_impedance);
> +	if (ret)
> +		als->als2_imp_sel = 0;
> +	else
> +		als->als2_imp_sel = lm3532_get_als_imp_index(als_impedance);
> +
> +	ret = device_property_read_u32(&priv->client->dev, "ti,als-avrg-time-us",
> +				      &als_avg_time);
> +	if (ret)
> +		als->als_avrg_time = 0;
> +	else
> +		als->als_avrg_time = lm3532_get_als_avg_index(als_avg_time);
> +
> +	ret = device_property_read_u8(&priv->client->dev, "ti,als-input-mode",
> +				      &als->als_input_mode);
> +	if (ret)
> +		als->als_input_mode = 0;
> +
> +	if (als->als_input_mode > LM3532_BL_MODE_ALS) {
> +		ret = -EINVAL;
> +		return ret;
> +	}
> +
> +	priv->als_data = als;
> +
> +	return ret;
> +}
> +
> +static int lm3532_parse_node(struct lm3532_data *priv)
> +{
> +	struct fwnode_handle *child = NULL;
> +	struct lm3532_led *led;
> +	const char *name;
> +	int control_bank;
> +	u32 ramp_time;
> +	size_t i = 0;
> +	int ret;
> +
> +	priv->enable_gpio = devm_gpiod_get_optional(&priv->client->dev,
> +						   "enable", GPIOD_OUT_LOW);
> +	if (IS_ERR(priv->enable_gpio))
> +		priv->enable_gpio = NULL;
> +
> +	priv->regulator = devm_regulator_get(&priv->client->dev, "vin");
> +	if (IS_ERR(priv->regulator))
> +		priv->regulator = NULL;
> +
> +	ret = device_property_read_u32(&priv->client->dev, "ramp-up-us",
> +				       &ramp_time);
> +	if (ret)
> +		dev_info(&priv->client->dev, "ramp-up-ms property missing\n");
> +	else
> +		priv->runtime_ramp_up = lm3532_get_ramp_index(ramp_time);
> +
> +	ret = device_property_read_u32(&priv->client->dev, "ramp-down-us",
> +				       &ramp_time);
> +	if (ret)
> +		dev_info(&priv->client->dev, "ramp-down-ms property missing\n");
> +	else
> +		priv->runtime_ramp_down = lm3532_get_ramp_index(ramp_time);
> +
> +	device_for_each_child_node(priv->dev, child) {
> +		led = &priv->leds[i];
> +
> +		ret = fwnode_property_read_u32(child, "reg", &control_bank);
> +		if (ret) {
> +			dev_err(&priv->client->dev, "reg property missing\n");
> +			fwnode_handle_put(child);
> +			goto child_out;
> +		}
> +
> +		if (control_bank > LM3532_CONTROL_C) {
> +			dev_err(&priv->client->dev, "Control bank invalid\n");
> +			continue;
> +		}
> +
> +		led->control_bank = control_bank;
> +
> +		ret = fwnode_property_read_u32(child, "ti,led-mode",
> +					       &led->mode);
> +		if (ret) {
> +			dev_err(&priv->client->dev, "ti,led-mode property missing\n");
> +			fwnode_handle_put(child);
> +			goto child_out;
> +		}
> +
> +		if (led->mode == LM3532_BL_MODE_ALS) {
> +			ret = lm3532_parse_als(priv);
> +			if (ret)
> +				dev_err(&priv->client->dev, "Failed to parse als\n");
> +			else
> +				lm3532_als_configure(priv, led);
> +		}
> +
> +		led->num_leds = fwnode_property_read_u32_array(child,
> +							       "led-sources",
> +							       NULL, 0);
> +
> +		if (led->num_leds > LM3532_MAX_LED_STRINGS) {
> +			dev_err(&priv->client->dev, "To many LED string defined\n");
> +			continue;
> +		}
> +
> +		ret = fwnode_property_read_u32_array(child, "led-sources",
> +						    led->led_strings,
> +						    led->num_leds);
> +		if (ret) {
> +			dev_err(&priv->client->dev, "led-sources property missing\n");
> +			fwnode_handle_put(child);
> +			goto child_out;
> +		}
> +
> +		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::", priv->client->name);
> +		else
> +			snprintf(led->label, sizeof(led->label),
> +				 "%s:%s", priv->client->name, name);
> +
> +		led->priv = priv;
> +		led->led_dev.name = led->label;
> +		led->led_dev.brightness_set_blocking = lm3532_brightness_set;
> +
> +		ret = devm_led_classdev_register(priv->dev, &led->led_dev);
> +		if (ret) {
> +			dev_err(&priv->client->dev, "led register err: %d\n",
> +				ret);
> +			fwnode_handle_put(child);
> +			goto child_out;
> +		}
> +
> +		lm3532_init_registers(led);
> +
> +		i++;
> +	}
> +
> +child_out:
> +	return ret;
> +}
> +
> +static int lm3532_probe(struct i2c_client *client,
> +			   const struct i2c_device_id *id)
> +{
> +	struct lm3532_data *drvdata;
> +	int ret = 0;
> +	int count;
> +
> +	count = device_get_child_node_count(&client->dev);
> +	if (!count) {
> +		dev_err(&client->dev, "LEDs are not defined in device tree!");
> +		return -ENODEV;
> +	}
> +
> +	drvdata = devm_kzalloc(&client->dev, struct_size(drvdata, leds, count),
> +			   GFP_KERNEL);
> +	if (drvdata == NULL)
> +		return -ENOMEM;
> +
> +	drvdata->client = client;
> +	drvdata->dev = &client->dev;
> +
> +	drvdata->regmap = devm_regmap_init_i2c(client, &lm3532_regmap_config);
> +	if (IS_ERR(drvdata->regmap)) {
> +		ret = PTR_ERR(drvdata->regmap);
> +		dev_err(&client->dev, "Failed to allocate register map: %d\n",
> +			ret);
> +		return ret;
> +	}
> +
> +	mutex_init(&drvdata->lock);
> +	i2c_set_clientdata(client, drvdata);
> +
> +	ret = lm3532_parse_node(drvdata);
> +	if (ret) {
> +		dev_err(&client->dev, "Failed to parse node\n");
> +		return ret;
> +	}
> +
> +	if (drvdata->enable_gpio)
> +		gpiod_direction_output(drvdata->enable_gpio, 1);
> +
> +	return ret;
> +}
> +
> +static int lm3532_remove(struct i2c_client *client)
> +{
> +	struct lm3532_data *drvdata = i2c_get_clientdata(client);
mutex_destroy(&drvdata->lock);

> +	if (drvdata->enable_gpio)
> +		gpiod_direction_output(drvdata->enable_gpio, 0);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id of_lm3532_leds_match[] = {
> +	{ .compatible = "ti,lm3532", },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, of_lm3532_leds_match);
> +
> +static const struct i2c_device_id lm3532_id[] = {
> +	{LM3532_NAME, 0},
> +	{}
> +};
> +MODULE_DEVICE_TABLE(i2c, lm3532_id);
> +
> +static struct i2c_driver lm3532_i2c_driver = {
> +	.probe = lm3532_probe,
> +	.remove = lm3532_remove,
> +	.id_table = lm3532_id,
> +	.driver = {
> +		.name = LM3532_NAME,
> +		.of_match_table = of_lm3532_leds_match,
> +	},
> +};
> +module_i2c_driver(lm3532_i2c_driver);
> +
> +MODULE_DESCRIPTION("Back Light driver for LM3532");
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
>
Jacek Anaszewski March 20, 2019, 7 p.m. UTC | #3
Hi Dan,

On 3/20/19 1:39 PM, Dan Murphy wrote:
> Hello
> 
> On 3/13/19 7:32 AM, Dan Murphy wrote:
>> Introduce the Texas Instruments LM3532 White LED driver.
>> The driver supports ALS configurability or manual brightness
>> control.
>>
>> The driver also supports associating LED strings with specific
>> control banks in a group or as individually controlled strings.
>>
> 
> I have a v5 series ready for posting and only the DT was reviewed.
> 
> Do we have any comments on the code?

I've just added one comment. After it is addressed please submit v5.
Dan Murphy March 20, 2019, 7:04 p.m. UTC | #4
Jacek

On 3/20/19 1:59 PM, Jacek Anaszewski wrote:
> Hi Dan,
> 
> I have one minor issue below.
> 
> On 3/13/19 1:32 PM, Dan Murphy wrote:
>> Introduce the Texas Instruments LM3532 White LED driver.
>> The driver supports ALS configurability or manual brightness
>> control.
>>
>> The driver also supports associating LED strings with specific
>> control banks in a group or as individually controlled strings.
>>
>> Signed-off-by: Dan Murphy <dmurphy@ti.com>
>> ---
>>
>> v4 - Updated code to DT doc changes appending "ti," to TI specific properties -
>> https://lore.kernel.org/patchwork/patch/1050124/
>>
>> v3 - Removed switch case for register setting in favor of an algorithim (v1 comment),
>> https://lore.kernel.org/patchwork/patch/1049024/
>> v2 - Added look up tables for als_avg, als_imp and ramp times, fixed brightness
>> control when ALS is in control, added property value checks to ensure the values
>> are not out of bounds - https://lore.kernel.org/patchwork/patch/1048807/
>>
>>   drivers/leds/Kconfig       |  10 +
>>   drivers/leds/Makefile      |   1 +
>>   drivers/leds/leds-lm3532.c | 681 +++++++++++++++++++++++++++++++++++++
>>   3 files changed, 692 insertions(+)
>>   create mode 100644 drivers/leds/leds-lm3532.c
>>
>> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
>> index a72f97fca57b..da00b9ed5a5c 100644
>> --- a/drivers/leds/Kconfig
>> +++ b/drivers/leds/Kconfig
>> @@ -138,6 +138,16 @@ config LEDS_LM3530
>>         controlled manually or using PWM input or using ambient
>>         light automatically.
>>   +config LEDS_LM3532
>> +    tristate "LCD Backlight driver for LM3532"
>> +    depends on LEDS_CLASS
>> +    depends on I2C
>> +    help
>> +      This option enables support for the LCD backlight using
>> +      LM3532 ambient light sensor chip. This ALS chip can be
>> +      controlled manually or using PWM input or using ambient
>> +      light automatically.
>> +
>>   config LEDS_LM3533
>>       tristate "LED support for LM3533"
>>       depends on LEDS_CLASS
>> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
>> index 4c1b0054f379..7a8b1f55d459 100644
>> --- a/drivers/leds/Makefile
>> +++ b/drivers/leds/Makefile
>> @@ -18,6 +18,7 @@ obj-$(CONFIG_LEDS_BD2802)        += leds-bd2802.o
>>   obj-$(CONFIG_LEDS_CPCAP)        += leds-cpcap.o
>>   obj-$(CONFIG_LEDS_LOCOMO)        += leds-locomo.o
>>   obj-$(CONFIG_LEDS_LM3530)        += leds-lm3530.o
>> +obj-$(CONFIG_LEDS_LM3532)        += leds-lm3532.o
>>   obj-$(CONFIG_LEDS_LM3533)        += leds-lm3533.o
>>   obj-$(CONFIG_LEDS_LM3642)        += leds-lm3642.o
>>   obj-$(CONFIG_LEDS_MIKROTIK_RB532)    += leds-rb532.o
>> diff --git a/drivers/leds/leds-lm3532.c b/drivers/leds/leds-lm3532.c
>> new file mode 100644
>> index 000000000000..e8a614d71469
>> --- /dev/null
>> +++ b/drivers/leds/leds-lm3532.c
>> @@ -0,0 +1,681 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +// TI LM3532 LED driver
>> +// Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/
>> +
>> +#include <linux/i2c.h>
>> +#include <linux/leds.h>
>> +#include <linux/slab.h>
>> +#include <linux/regmap.h>
>> +#include <linux/types.h>
>> +#include <linux/regulator/consumer.h>
>> +#include <linux/module.h>
>> +#include <uapi/linux/uleds.h>
>> +#include <linux/gpio/consumer.h>
>> +
>> +#define LM3532_NAME "lm3532-led"
>> +#define LM3532_BL_MODE_MANUAL    0x00
>> +#define LM3532_BL_MODE_ALS    0x01
>> +
>> +#define LM3532_REG_OUTPUT_CFG    0x10
>> +#define LM3532_REG_STARTSHUT_RAMP    0x11
>> +#define LM3532_REG_RT_RAMP    0x12
>> +#define LM3532_REG_PWM_A_CFG    0x13
>> +#define LM3532_REG_PWM_B_CFG    0x14
>> +#define LM3532_REG_PWM_C_CFG    0x15
>> +#define LM3532_REG_ZONE_CFG_A    0x16
>> +#define LM3532_REG_CTRL_A_BRT    0x17
>> +#define LM3532_REG_ZONE_CFG_B    0x18
>> +#define LM3532_REG_CTRL_B_BRT    0x19
>> +#define LM3532_REG_ZONE_CFG_C    0x1a
>> +#define LM3532_REG_CTRL_C_BRT    0x1b
>> +#define LM3532_REG_ENABLE    0x1d
>> +#define LM3532_ALS_CONFIG    0x23
>> +#define LM3532_REG_ZN_0_HI    0x60
>> +#define LM3532_REG_ZN_0_LO    0x61
>> +#define LM3532_REG_ZN_1_HI    0x62
>> +#define LM3532_REG_ZN_1_LO    0x63
>> +#define LM3532_REG_ZN_2_HI    0x64
>> +#define LM3532_REG_ZN_2_LO    0x65
>> +#define LM3532_REG_ZN_3_HI    0x66
>> +#define LM3532_REG_ZN_3_LO    0x67
>> +#define LM3532_REG_MAX        0x7e
>> +
>> +/* Contorl Enable */
>> +#define LM3532_CTRL_A_ENABLE    BIT(0)
>> +#define LM3532_CTRL_B_ENABLE    BIT(1)
>> +#define LM3532_CTRL_C_ENABLE    BIT(2)
>> +
>> +/* PWM Zone Control */
>> +#define LM3532_PWM_ZONE_MASK    0x7c
>> +#define LM3532_PWM_ZONE_0_EN    BIT(2)
>> +#define LM3532_PWM_ZONE_1_EN    BIT(3)
>> +#define LM3532_PWM_ZONE_2_EN    BIT(4)
>> +#define LM3532_PWM_ZONE_3_EN    BIT(5)
>> +#define LM3532_PWM_ZONE_4_EN    BIT(6)
>> +
>> +/* Brightness Configuration */
>> +#define LM3532_I2C_CTRL        BIT(0)
>> +#define LM3532_ALS_CTRL        0
>> +#define LM3532_LINEAR_MAP    BIT(1)
>> +#define LM3532_ZONE_MASK    (BIT(2) | BIT(3) | BIT(4))
>> +#define LM3532_ZONE_0        0
>> +#define LM3532_ZONE_1        BIT(2)
>> +#define LM3532_ZONE_2        BIT(3)
>> +#define LM3532_ZONE_3        (BIT(2) | BIT(3))
>> +#define LM3532_ZONE_4        BIT(4)
>> +
>> +#define LM3532_ENABLE_ALS    BIT(3)
>> +#define LM3532_ALS_SEL_SHIFT    6
>> +
>> +/* Zone Boundary Register */
>> +#define LM3532_ALS_WINDOW_mV    2000
>> +#define LM3532_ALS_ZB_MAX    4
>> +#define LM3532_ALS_OFFSET_mV    2
>> +
>> +#define LM3532_CONTROL_A    0
>> +#define LM3532_CONTROL_B    1
>> +#define LM3532_CONTROL_C    2
>> +#define LM3532_MAX_CONTROL_BANKS 3
>> +#define LM3532_MAX_LED_STRINGS    3
>> +
>> +#define LM3532_OUTPUT_CFG_MASK    0x3
>> +#define LM3532_BRT_VAL_ADJUST    8
>> +#define LM3532_RAMP_DOWN_SHIFT    3
>> +
>> +#define LM3532_NUM_RAMP_VALS    8
>> +#define LM3532_NUM_AVG_VALS    8
>> +#define LM3532_NUM_IMP_VALS    32
>> +
>> +/*
>> + * struct lm3532_als_data
>> + * @config - value of ALS configuration register
>> + * @als1_imp_sel - value of ALS1 resistor select register
>> + * @als2_imp_sel - value of ALS2 resistor select register
>> + * @als_avrg_time - ALS averaging time
>> + * @als_input_mode - ALS input mode for brightness control
>> + * @als_vmin - Minimum ALS voltage
>> + * @als_vmax - Maximum ALS voltage
>> + * @zone_lo - values of ALS lo ZB(Zone Boundary) registers
>> + * @zone_hi - values of ALS hi ZB(Zone Boundary) registers
>> + */
>> +struct lm3532_als_data {
>> +    u8 config;
>> +    u8 als1_imp_sel;
>> +    u8 als2_imp_sel;
>> +    u8 als_avrg_time;
>> +    u8 als_input_mode;
>> +    u32 als_vmin;
>> +    u32 als_vmax;
>> +    u8 zones_lo[LM3532_ALS_ZB_MAX];
>> +    u8 zones_hi[LM3532_ALS_ZB_MAX];
>> +};
>> +
>> +/**
>> + * struct lm3532_led
>> + * @led_dev: led class device
>> + * @priv - Pointer the device data structure
>> + * @control_bank - Control bank the LED is associated to
>> + * @mode - Mode of the LED string
>> + * @num_leds - Number of LED strings are supported in this array
>> + * @led_strings - The LED strings supported in this array
>> + * @label - LED label
>> + */
>> +struct lm3532_led {
>> +    struct led_classdev led_dev;
>> +    struct lm3532_data *priv;
>> +
>> +    int control_bank;
>> +    int mode;
>> +    int num_leds;
>> +    u32 led_strings[LM3532_MAX_CONTROL_BANKS];
>> +    char label[LED_MAX_NAME_SIZE];
>> +};
>> +
>> +/**
>> + * struct lm3532_data
>> + * @enable_gpio - Hardware enable gpio
>> + * @regulator: regulator
>> + * @client: i2c client
>> + * @regmap - Devices register map
>> + * @dev - Pointer to the devices device struct
>> + * @lock - Lock for reading/writing the device
>> + * @als_data - Pointer to the als data struct
>> + * @runtime_ramp_up - Runtime ramp up setting
>> + * @runtime_ramp_down - Runtime ramp down setting
>> + * @leds - Array of LED strings
>> + */
>> +struct lm3532_data {
>> +    struct gpio_desc *enable_gpio;
>> +    struct regulator *regulator;
>> +    struct i2c_client *client;
>> +    struct regmap *regmap;
>> +    struct device *dev;
>> +    struct mutex lock;
>> +
>> +    struct lm3532_als_data *als_data;
>> +
>> +    u32 runtime_ramp_up;
>> +    u32 runtime_ramp_down;
>> +
>> +    struct lm3532_led leds[];
>> +};
>> +
>> +static const struct reg_default lm3532_reg_defs[] = {
>> +    {LM3532_REG_OUTPUT_CFG, 0xe4},
>> +    {LM3532_REG_STARTSHUT_RAMP, 0xc0},
>> +    {LM3532_REG_RT_RAMP, 0xc0},
>> +    {LM3532_REG_PWM_A_CFG, 0x82},
>> +    {LM3532_REG_PWM_B_CFG, 0x82},
>> +    {LM3532_REG_PWM_C_CFG, 0x82},
>> +    {LM3532_REG_ZONE_CFG_A, 0xf1},
>> +    {LM3532_REG_CTRL_A_BRT, 0xf3},
>> +    {LM3532_REG_ZONE_CFG_B, 0xf1},
>> +    {LM3532_REG_CTRL_B_BRT, 0xf3},
>> +    {LM3532_REG_ZONE_CFG_C, 0xf1},
>> +    {LM3532_REG_CTRL_C_BRT, 0xf3},
>> +    {LM3532_REG_ENABLE, 0xf8},
>> +    {LM3532_ALS_CONFIG, 0x44},
>> +    {LM3532_REG_ZN_0_HI, 0x35},
>> +    {LM3532_REG_ZN_0_LO, 0x33},
>> +    {LM3532_REG_ZN_1_HI, 0x6a},
>> +    {LM3532_REG_ZN_1_LO, 0x66},
>> +    {LM3532_REG_ZN_2_HI, 0xa1},
>> +    {LM3532_REG_ZN_2_LO, 0x99},
>> +    {LM3532_REG_ZN_3_HI, 0xdc},
>> +    {LM3532_REG_ZN_3_LO, 0xcc},
>> +};
>> +
>> +static const struct regmap_config lm3532_regmap_config = {
>> +    .reg_bits = 8,
>> +    .val_bits = 8,
>> +
>> +    .max_register = LM3532_REG_MAX,
>> +    .reg_defaults = lm3532_reg_defs,
>> +    .num_reg_defaults = ARRAY_SIZE(lm3532_reg_defs),
>> +    .cache_type = REGCACHE_FLAT,
>> +};
>> +
>> +const static int als_imp_table[LM3532_NUM_IMP_VALS] = {37000, 18500, 12330,
>> +                               92500, 7400, 6170, 5290,
>> +                               4630, 4110, 3700, 3360,
>> +                               3080, 2850, 2640, 2440,
>> +                               2310, 2180, 2060, 1950,
>> +                               1850, 1760, 1680, 1610,
>> +                               1540, 1480, 1420, 1370,
>> +                               1320, 1280, 1230, 1190};
>> +static int lm3532_get_als_imp_index(int als_imped)
>> +{
>> +    int i;
>> +
>> +    if (als_imped > als_imp_table[1])
>> +        return 0;
>> +
>> +    if (als_imped < als_imp_table[LM3532_NUM_IMP_VALS - 1])
>> +        return LM3532_NUM_IMP_VALS - 1;
>> +
>> +    for (i = 1; i < LM3532_NUM_IMP_VALS; i++) {
>> +        if (als_imped == als_imp_table[i])
>> +            return i;
>> +
>> +        /* Find an approximate index by looking up the table */
>> +        if (als_imped < als_imp_table[i - 1] &&
>> +            als_imped > als_imp_table[i]) {
>> +            if (als_imped - als_imp_table[i - 1] <
>> +                als_imp_table[i] - als_imped)
>> +                return i + 1;
>> +            else
>> +                return i;
>> +        }
>> +    }
>> +
>> +    return -EINVAL;
>> +}
>> +
>> +static int lm3532_get_index(const int table[], int size, int value)
>> +{
>> +    int i;
>> +
>> +    for (i = 1; i < size; i++) {
>> +        if (value == table[i])
>> +            return i;
>> +
>> +        /* Find an approximate index by looking up the table */
>> +        if (value > table[i - 1] &&
>> +            value < table[i]) {
>> +            if (value - table[i - 1] < table[i] - value)
>> +                return i - 1;
>> +            else
>> +                return i;
>> +        }
>> +    }
>> +
>> +    return -EINVAL;
>> +}
>> +
>> +const static int als_avrg_table[LM3532_NUM_AVG_VALS] = {17920, 35840, 71680,
>> +                            1433360, 286720, 573440,
>> +                            1146880, 2293760};
>> +static int lm3532_get_als_avg_index(int avg_time)
>> +{
>> +    if (avg_time <= als_avrg_table[0])
>> +        return 0;
>> +
>> +    if (avg_time > als_avrg_table[LM3532_NUM_AVG_VALS - 1])
>> +        return LM3532_NUM_AVG_VALS - 1;
>> +
>> +    return lm3532_get_index(&als_avrg_table[0], LM3532_NUM_AVG_VALS,
>> +                avg_time);
>> +}
>> +
>> +const static int ramp_table[LM3532_NUM_RAMP_VALS] = { 8, 1024, 2048, 4096, 8192,
>> +                             16384, 32768, 65536};
>> +static int lm3532_get_ramp_index(int ramp_time)
>> +{
>> +    if (ramp_time <= ramp_table[0])
>> +        return 0;
>> +
>> +    if (ramp_time > ramp_table[LM3532_NUM_RAMP_VALS - 1])
>> +        return LM3532_NUM_RAMP_VALS - 1;
>> +
>> +    return lm3532_get_index(&ramp_table[0], LM3532_NUM_RAMP_VALS,
>> +                ramp_time);
>> +}
>> +
>> +static int lm3532_led_enable(struct lm3532_led *led_data)
>> +{
>> +    int ctrl_en_val = BIT(led_data->control_bank);
>> +    int ret;
>> +
>> +    ret = regmap_update_bits(led_data->priv->regmap, LM3532_REG_ENABLE,
>> +                     ctrl_en_val, ctrl_en_val);
>> +    if (ret) {
>> +        dev_err(led_data->priv->dev, "Failed to set ctrl:%d\n", ret);
>> +        return ret;
>> +    }
>> +
>> +    return regulator_enable(led_data->priv->regulator);
>> +}
>> +
>> +static int lm3532_led_disable(struct lm3532_led *led_data)
>> +{
>> +    int ctrl_en_val = BIT(led_data->control_bank);
>> +    int ret;
>> +
>> +    ret = regmap_update_bits(led_data->priv->regmap, LM3532_REG_ENABLE,
>> +                     ctrl_en_val, ~ctrl_en_val);
>> +    if (ret) {
>> +        dev_err(led_data->priv->dev, "Failed to set ctrl:%d\n", ret);
>> +        return ret;
>> +    }
>> +
>> +    return regulator_disable(led_data->priv->regulator);
>> +}
>> +
>> +static int lm3532_brightness_set(struct led_classdev *led_cdev,
>> +                 enum led_brightness brt_val)
>> +{
>> +    struct lm3532_led *led =
>> +            container_of(led_cdev, struct lm3532_led, led_dev);
>> +    u8 brightness_reg;
>> +    int ret;
>> +
>> +    mutex_lock(&led->priv->lock);
>> +
>> +    if (led->mode == LM3532_BL_MODE_ALS) {
>> +        if (brt_val > LED_OFF)
>> +            ret = lm3532_led_enable(led);
>> +        else
>> +            ret = lm3532_led_disable(led);
>> +
>> +        goto unlock;
>> +    }
>> +
>> +    if (brt_val == LED_OFF) {
>> +        ret = lm3532_led_disable(led);
>> +        goto unlock;
>> +    }
>> +
>> +    ret = lm3532_led_enable(led);
>> +    if (ret)
>> +        goto unlock;
>> +
>> +    brightness_reg = LM3532_REG_CTRL_A_BRT + led->control_bank * 2;
>> +    brt_val = brt_val / LM3532_BRT_VAL_ADJUST;
>> +
>> +    ret = regmap_write(led->priv->regmap, brightness_reg, brt_val);
>> +
>> +unlock:
>> +    mutex_unlock(&led->priv->lock);
>> +    return ret;
>> +}
>> +
>> +static int lm3532_init_registers(struct lm3532_led *led)
>> +{
>> +    struct lm3532_data *drvdata = led->priv;
>> +    unsigned int runtime_ramp_val;
>> +    unsigned int output_cfg_val = 0;
>> +    unsigned int output_cfg_shift = 0;
>> +    unsigned int output_cfg_mask = 0;
>> +    int ret, i;
>> +
>> +    for (i = 0; i < led->num_leds; i++) {
>> +        output_cfg_shift = led->led_strings[i] * 2;
>> +        output_cfg_val |= (led->control_bank << output_cfg_shift);
>> +        output_cfg_mask |= LM3532_OUTPUT_CFG_MASK << output_cfg_shift;
>> +    }
>> +
>> +    ret = regmap_update_bits(drvdata->regmap, LM3532_REG_OUTPUT_CFG,
>> +                 output_cfg_mask, output_cfg_val);
>> +    if (ret)
>> +        return ret;
>> +
>> +    runtime_ramp_val = drvdata->runtime_ramp_up |
>> +             (drvdata->runtime_ramp_down << LM3532_RAMP_DOWN_SHIFT);
>> +
>> +    return regmap_write(drvdata->regmap, LM3532_REG_RT_RAMP,
>> +                runtime_ramp_val);
>> +}
>> +
>> +static int lm3532_als_configure(struct lm3532_data *priv,
>> +                struct lm3532_led *led)
>> +{
>> +    struct lm3532_als_data *als = priv->als_data;
>> +    u32 als_vmin, als_vmax, als_vstep;
>> +    int zone_reg = LM3532_REG_ZN_0_HI;
>> +    int brightnes_config_reg;
>> +    int ret;
>> +    int i;
>> +
>> +    als_vmin = als->als_vmin;
>> +    als_vmax = als->als_vmax;
>> +
>> +    als_vstep = (als_vmax - als_vmin) / ((LM3532_ALS_ZB_MAX + 1) * 2);
>> +
>> +    for (i = 0; i < LM3532_ALS_ZB_MAX; i++) {
>> +        als->zones_lo[i] = ((als_vmin + als_vstep + (i * als_vstep)) *
>> +                LED_FULL) / 1000;
>> +        als->zones_hi[i] = ((als_vmin + LM3532_ALS_OFFSET_mV +
>> +                als_vstep + (i * als_vstep)) * LED_FULL) / 1000;
>> +
>> +        zone_reg = LM3532_REG_ZN_0_HI + i * 2;
>> +        ret = regmap_write(priv->regmap, zone_reg, als->zones_lo[i]);
>> +        if (ret)
>> +            return ret;
>> +
>> +        zone_reg += 1;
>> +        ret = regmap_write(priv->regmap, zone_reg, als->zones_hi[i]);
>> +        if (ret)
>> +            return ret;
>> +    }
>> +
>> +    als->config = (als->als_avrg_time | (LM3532_ENABLE_ALS) |
>> +        (als->als_input_mode << LM3532_ALS_SEL_SHIFT));
>> +
>> +    ret = regmap_write(priv->regmap, LM3532_ALS_CONFIG, als->config);
>> +    if (ret)
>> +        return ret;
>> +
>> +    brightnes_config_reg = LM3532_REG_ZONE_CFG_A + led->control_bank * 2;
>> +
>> +    return regmap_update_bits(priv->regmap, brightnes_config_reg,
>> +                  LM3532_I2C_CTRL, LM3532_ALS_CTRL);
>> +}
>> +
>> +static int lm3532_parse_als(struct lm3532_data *priv)
>> +{
>> +    struct lm3532_als_data *als;
>> +    int als_avg_time;
>> +    int als_impedance;
>> +    int ret;
>> +
>> +    als = devm_kzalloc(priv->dev, sizeof(*als), GFP_KERNEL);
>> +    if (als == NULL)
>> +        return -ENOMEM;
>> +
>> +    ret = device_property_read_u32(&priv->client->dev, "ti,als-vmin",
>> +                       &als->als_vmin);
>> +    if (ret)
>> +        als->als_vmin = 0;
>> +
>> +    ret = device_property_read_u32(&priv->client->dev, "ti,als-vmax",
>> +                       &als->als_vmax);
>> +    if (ret)
>> +        als->als_vmax = LM3532_ALS_WINDOW_mV;
>> +
>> +    if (als->als_vmax > LM3532_ALS_WINDOW_mV) {
>> +        ret = -EINVAL;
>> +        return ret;
>> +    }
>> +
>> +    ret = device_property_read_u32(&priv->client->dev, "ti,als1-imp-sel",
>> +                      &als_impedance);
>> +    if (ret)
>> +        als->als1_imp_sel = 0;
>> +    else
>> +        als->als1_imp_sel = lm3532_get_als_imp_index(als_impedance);
>> +
>> +    ret = device_property_read_u32(&priv->client->dev, "ti,als2-imp-sel",
>> +                      &als_impedance);
>> +    if (ret)
>> +        als->als2_imp_sel = 0;
>> +    else
>> +        als->als2_imp_sel = lm3532_get_als_imp_index(als_impedance);
>> +
>> +    ret = device_property_read_u32(&priv->client->dev, "ti,als-avrg-time-us",
>> +                      &als_avg_time);
>> +    if (ret)
>> +        als->als_avrg_time = 0;
>> +    else
>> +        als->als_avrg_time = lm3532_get_als_avg_index(als_avg_time);
>> +
>> +    ret = device_property_read_u8(&priv->client->dev, "ti,als-input-mode",
>> +                      &als->als_input_mode);
>> +    if (ret)
>> +        als->als_input_mode = 0;
>> +
>> +    if (als->als_input_mode > LM3532_BL_MODE_ALS) {
>> +        ret = -EINVAL;
>> +        return ret;
>> +    }
>> +
>> +    priv->als_data = als;
>> +
>> +    return ret;
>> +}
>> +
>> +static int lm3532_parse_node(struct lm3532_data *priv)
>> +{
>> +    struct fwnode_handle *child = NULL;
>> +    struct lm3532_led *led;
>> +    const char *name;
>> +    int control_bank;
>> +    u32 ramp_time;
>> +    size_t i = 0;
>> +    int ret;
>> +
>> +    priv->enable_gpio = devm_gpiod_get_optional(&priv->client->dev,
>> +                           "enable", GPIOD_OUT_LOW);
>> +    if (IS_ERR(priv->enable_gpio))
>> +        priv->enable_gpio = NULL;
>> +
>> +    priv->regulator = devm_regulator_get(&priv->client->dev, "vin");
>> +    if (IS_ERR(priv->regulator))
>> +        priv->regulator = NULL;
>> +
>> +    ret = device_property_read_u32(&priv->client->dev, "ramp-up-us",
>> +                       &ramp_time);
>> +    if (ret)
>> +        dev_info(&priv->client->dev, "ramp-up-ms property missing\n");
>> +    else
>> +        priv->runtime_ramp_up = lm3532_get_ramp_index(ramp_time);
>> +
>> +    ret = device_property_read_u32(&priv->client->dev, "ramp-down-us",
>> +                       &ramp_time);
>> +    if (ret)
>> +        dev_info(&priv->client->dev, "ramp-down-ms property missing\n");
>> +    else
>> +        priv->runtime_ramp_down = lm3532_get_ramp_index(ramp_time);
>> +
>> +    device_for_each_child_node(priv->dev, child) {
>> +        led = &priv->leds[i];
>> +
>> +        ret = fwnode_property_read_u32(child, "reg", &control_bank);
>> +        if (ret) {
>> +            dev_err(&priv->client->dev, "reg property missing\n");
>> +            fwnode_handle_put(child);
>> +            goto child_out;
>> +        }
>> +
>> +        if (control_bank > LM3532_CONTROL_C) {
>> +            dev_err(&priv->client->dev, "Control bank invalid\n");
>> +            continue;
>> +        }
>> +
>> +        led->control_bank = control_bank;
>> +
>> +        ret = fwnode_property_read_u32(child, "ti,led-mode",
>> +                           &led->mode);
>> +        if (ret) {
>> +            dev_err(&priv->client->dev, "ti,led-mode property missing\n");
>> +            fwnode_handle_put(child);
>> +            goto child_out;
>> +        }
>> +
>> +        if (led->mode == LM3532_BL_MODE_ALS) {
>> +            ret = lm3532_parse_als(priv);
>> +            if (ret)
>> +                dev_err(&priv->client->dev, "Failed to parse als\n");
>> +            else
>> +                lm3532_als_configure(priv, led);
>> +        }
>> +
>> +        led->num_leds = fwnode_property_read_u32_array(child,
>> +                                   "led-sources",
>> +                                   NULL, 0);
>> +
>> +        if (led->num_leds > LM3532_MAX_LED_STRINGS) {
>> +            dev_err(&priv->client->dev, "To many LED string defined\n");
>> +            continue;
>> +        }
>> +
>> +        ret = fwnode_property_read_u32_array(child, "led-sources",
>> +                            led->led_strings,
>> +                            led->num_leds);
>> +        if (ret) {
>> +            dev_err(&priv->client->dev, "led-sources property missing\n");
>> +            fwnode_handle_put(child);
>> +            goto child_out;
>> +        }
>> +
>> +        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::", priv->client->name);
>> +        else
>> +            snprintf(led->label, sizeof(led->label),
>> +                 "%s:%s", priv->client->name, name);
>> +
>> +        led->priv = priv;
>> +        led->led_dev.name = led->label;
>> +        led->led_dev.brightness_set_blocking = lm3532_brightness_set;
>> +
>> +        ret = devm_led_classdev_register(priv->dev, &led->led_dev);
>> +        if (ret) {
>> +            dev_err(&priv->client->dev, "led register err: %d\n",
>> +                ret);
>> +            fwnode_handle_put(child);
>> +            goto child_out;
>> +        }
>> +
>> +        lm3532_init_registers(led);
>> +
>> +        i++;
>> +    }
>> +
>> +child_out:
>> +    return ret;
>> +}
>> +
>> +static int lm3532_probe(struct i2c_client *client,
>> +               const struct i2c_device_id *id)
>> +{
>> +    struct lm3532_data *drvdata;
>> +    int ret = 0;
>> +    int count;
>> +
>> +    count = device_get_child_node_count(&client->dev);
>> +    if (!count) {
>> +        dev_err(&client->dev, "LEDs are not defined in device tree!");
>> +        return -ENODEV;
>> +    }
>> +
>> +    drvdata = devm_kzalloc(&client->dev, struct_size(drvdata, leds, count),
>> +               GFP_KERNEL);
>> +    if (drvdata == NULL)
>> +        return -ENOMEM;
>> +
>> +    drvdata->client = client;
>> +    drvdata->dev = &client->dev;
>> +
>> +    drvdata->regmap = devm_regmap_init_i2c(client, &lm3532_regmap_config);
>> +    if (IS_ERR(drvdata->regmap)) {
>> +        ret = PTR_ERR(drvdata->regmap);
>> +        dev_err(&client->dev, "Failed to allocate register map: %d\n",
>> +            ret);
>> +        return ret;
>> +    }
>> +
>> +    mutex_init(&drvdata->lock);
>> +    i2c_set_clientdata(client, drvdata);
>> +
>> +    ret = lm3532_parse_node(drvdata);
>> +    if (ret) {
>> +        dev_err(&client->dev, "Failed to parse node\n");
>> +        return ret;
>> +    }
>> +
>> +    if (drvdata->enable_gpio)
>> +        gpiod_direction_output(drvdata->enable_gpio, 1);
>> +
>> +    return ret;
>> +}
>> +
>> +static int lm3532_remove(struct i2c_client *client)
>> +{
>> +    struct lm3532_data *drvdata = i2c_get_clientdata(client);
> mutex_destroy(&drvdata->lock);
> 

Ack.  I give post v5 tomorrow.

Dan


>> +    if (drvdata->enable_gpio)
>> +        gpiod_direction_output(drvdata->enable_gpio, 0);
>> +
>> +    return 0;
>> +}
>> +
>> +static const struct of_device_id of_lm3532_leds_match[] = {
>> +    { .compatible = "ti,lm3532", },
>> +    {},
>> +};
>> +MODULE_DEVICE_TABLE(of, of_lm3532_leds_match);
>> +
>> +static const struct i2c_device_id lm3532_id[] = {
>> +    {LM3532_NAME, 0},
>> +    {}
>> +};
>> +MODULE_DEVICE_TABLE(i2c, lm3532_id);
>> +
>> +static struct i2c_driver lm3532_i2c_driver = {
>> +    .probe = lm3532_probe,
>> +    .remove = lm3532_remove,
>> +    .id_table = lm3532_id,
>> +    .driver = {
>> +        .name = LM3532_NAME,
>> +        .of_match_table = of_lm3532_leds_match,
>> +    },
>> +};
>> +module_i2c_driver(lm3532_i2c_driver);
>> +
>> +MODULE_DESCRIPTION("Back Light driver for LM3532");
>> +MODULE_LICENSE("GPL v2");
>> +MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
>>
>
Dan Murphy March 20, 2019, 7:05 p.m. UTC | #5
Jacek

On 3/20/19 2:00 PM, Jacek Anaszewski wrote:
> Hi Dan,
> 
> On 3/20/19 1:39 PM, Dan Murphy wrote:
>> Hello
>>
>> On 3/13/19 7:32 AM, Dan Murphy wrote:
>>> Introduce the Texas Instruments LM3532 White LED driver.
>>> The driver supports ALS configurability or manual brightness
>>> control.
>>>
>>> The driver also supports associating LED strings with specific
>>> control banks in a group or as individually controlled strings.
>>>
>>
>> I have a v5 series ready for posting and only the DT was reviewed.
>>
>> Do we have any comments on the code?
> 
> I've just added one comment. After it is addressed please submit v5.
> 

Thank you.  I will give it through the night for others to comment and I will post
v5 tomorrow.

Dan
Lee Jones March 21, 2019, 8:20 a.m. UTC | #6
On Wed, 20 Mar 2019, Jacek Anaszewski wrote:

> Hi Dan,
> 
> I have one minor issue below.
> 
> On 3/13/19 1:32 PM, Dan Murphy wrote:
> > Introduce the Texas Instruments LM3532 White LED driver.
> > The driver supports ALS configurability or manual brightness
> > control.
> > 
> > The driver also supports associating LED strings with specific
> > control banks in a group or as individually controlled strings.
> > 
> > Signed-off-by: Dan Murphy <dmurphy@ti.com>
> > ---
> > 
> > v4 - Updated code to DT doc changes appending "ti," to TI specific properties -
> > https://lore.kernel.org/patchwork/patch/1050124/
> > 
> > v3 - Removed switch case for register setting in favor of an algorithim (v1 comment),
> > https://lore.kernel.org/patchwork/patch/1049024/
> > v2 - Added look up tables for als_avg, als_imp and ramp times, fixed brightness
> > control when ALS is in control, added property value checks to ensure the values
> > are not out of bounds - https://lore.kernel.org/patchwork/patch/1048807/
> > 
> >   drivers/leds/Kconfig       |  10 +
> >   drivers/leds/Makefile      |   1 +
> >   drivers/leds/leds-lm3532.c | 681 +++++++++++++++++++++++++++++++++++++
> >   3 files changed, 692 insertions(+)
> >   create mode 100644 drivers/leds/leds-lm3532.c

[snip]

> > diff --git a/drivers/leds/leds-lm3532.c b/drivers/leds/leds-lm3532.c
> > new file mode 100644
> > index 000000000000..e8a614d71469
> > --- /dev/null
> > +++ b/drivers/leds/leds-lm3532.c

[snip 700 lines of churn]

Jacek could you please trim your replies please?  It took way to long
to locate your one line comment in this 700 line patch.

> > +static int lm3532_remove(struct i2c_client *client)
> > +{
> > +	struct lm3532_data *drvdata = i2c_get_clientdata(client);
> mutex_destroy(&drvdata->lock);
Lee Jones March 21, 2019, 8:21 a.m. UTC | #7
On Wed, 20 Mar 2019, Dan Murphy wrote:
> On 3/20/19 1:59 PM, Jacek Anaszewski wrote:
> > On 3/13/19 1:32 PM, Dan Murphy wrote:
> >> Introduce the Texas Instruments LM3532 White LED driver.
> >> The driver supports ALS configurability or manual brightness
> >> control.
> >>
> >> The driver also supports associating LED strings with specific
> >> control banks in a group or as individually controlled strings.
> >>
> >> Signed-off-by: Dan Murphy <dmurphy@ti.com>
> >> ---
> >>
> >> v4 - Updated code to DT doc changes appending "ti," to TI specific properties -
> >> https://lore.kernel.org/patchwork/patch/1050124/
> >>
> >> v3 - Removed switch case for register setting in favor of an algorithim (v1 comment),
> >> https://lore.kernel.org/patchwork/patch/1049024/
> >> v2 - Added look up tables for als_avg, als_imp and ramp times, fixed brightness
> >> control when ALS is in control, added property value checks to ensure the values
> >> are not out of bounds - https://lore.kernel.org/patchwork/patch/1048807/
> >>
> >>   drivers/leds/Kconfig       |  10 +
> >>   drivers/leds/Makefile      |   1 +
> >>   drivers/leds/leds-lm3532.c | 681 +++++++++++++++++++++++++++++++++++++
> >>   3 files changed, 692 insertions(+)
> >>   create mode 100644 drivers/leds/leds-lm3532.c

[snip 700 lines of churn]

> Ack.  I give post v5 tomorrow.

Same for you too please Dan.

Patch
diff mbox series

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index a72f97fca57b..da00b9ed5a5c 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -138,6 +138,16 @@  config LEDS_LM3530
 	  controlled manually or using PWM input or using ambient
 	  light automatically.
 
+config LEDS_LM3532
+	tristate "LCD Backlight driver for LM3532"
+	depends on LEDS_CLASS
+	depends on I2C
+	help
+	  This option enables support for the LCD backlight using
+	  LM3532 ambient light sensor chip. This ALS chip can be
+	  controlled manually or using PWM input or using ambient
+	  light automatically.
+
 config LEDS_LM3533
 	tristate "LED support for LM3533"
 	depends on LEDS_CLASS
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 4c1b0054f379..7a8b1f55d459 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -18,6 +18,7 @@  obj-$(CONFIG_LEDS_BD2802)		+= leds-bd2802.o
 obj-$(CONFIG_LEDS_CPCAP)		+= leds-cpcap.o
 obj-$(CONFIG_LEDS_LOCOMO)		+= leds-locomo.o
 obj-$(CONFIG_LEDS_LM3530)		+= leds-lm3530.o
+obj-$(CONFIG_LEDS_LM3532)		+= leds-lm3532.o
 obj-$(CONFIG_LEDS_LM3533)		+= leds-lm3533.o
 obj-$(CONFIG_LEDS_LM3642)		+= leds-lm3642.o
 obj-$(CONFIG_LEDS_MIKROTIK_RB532)	+= leds-rb532.o
diff --git a/drivers/leds/leds-lm3532.c b/drivers/leds/leds-lm3532.c
new file mode 100644
index 000000000000..e8a614d71469
--- /dev/null
+++ b/drivers/leds/leds-lm3532.c
@@ -0,0 +1,681 @@ 
+// SPDX-License-Identifier: GPL-2.0
+// TI LM3532 LED driver
+// Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/
+
+#include <linux/i2c.h>
+#include <linux/leds.h>
+#include <linux/slab.h>
+#include <linux/regmap.h>
+#include <linux/types.h>
+#include <linux/regulator/consumer.h>
+#include <linux/module.h>
+#include <uapi/linux/uleds.h>
+#include <linux/gpio/consumer.h>
+
+#define LM3532_NAME "lm3532-led"
+#define LM3532_BL_MODE_MANUAL	0x00
+#define LM3532_BL_MODE_ALS	0x01
+
+#define LM3532_REG_OUTPUT_CFG	0x10
+#define LM3532_REG_STARTSHUT_RAMP	0x11
+#define LM3532_REG_RT_RAMP	0x12
+#define LM3532_REG_PWM_A_CFG	0x13
+#define LM3532_REG_PWM_B_CFG	0x14
+#define LM3532_REG_PWM_C_CFG	0x15
+#define LM3532_REG_ZONE_CFG_A	0x16
+#define LM3532_REG_CTRL_A_BRT	0x17
+#define LM3532_REG_ZONE_CFG_B	0x18
+#define LM3532_REG_CTRL_B_BRT	0x19
+#define LM3532_REG_ZONE_CFG_C	0x1a
+#define LM3532_REG_CTRL_C_BRT	0x1b
+#define LM3532_REG_ENABLE	0x1d
+#define LM3532_ALS_CONFIG	0x23
+#define LM3532_REG_ZN_0_HI	0x60
+#define LM3532_REG_ZN_0_LO	0x61
+#define LM3532_REG_ZN_1_HI	0x62
+#define LM3532_REG_ZN_1_LO	0x63
+#define LM3532_REG_ZN_2_HI	0x64
+#define LM3532_REG_ZN_2_LO	0x65
+#define LM3532_REG_ZN_3_HI	0x66
+#define LM3532_REG_ZN_3_LO	0x67
+#define LM3532_REG_MAX		0x7e
+
+/* Contorl Enable */
+#define LM3532_CTRL_A_ENABLE	BIT(0)
+#define LM3532_CTRL_B_ENABLE	BIT(1)
+#define LM3532_CTRL_C_ENABLE	BIT(2)
+
+/* PWM Zone Control */
+#define LM3532_PWM_ZONE_MASK	0x7c
+#define LM3532_PWM_ZONE_0_EN	BIT(2)
+#define LM3532_PWM_ZONE_1_EN	BIT(3)
+#define LM3532_PWM_ZONE_2_EN	BIT(4)
+#define LM3532_PWM_ZONE_3_EN	BIT(5)
+#define LM3532_PWM_ZONE_4_EN	BIT(6)
+
+/* Brightness Configuration */
+#define LM3532_I2C_CTRL		BIT(0)
+#define LM3532_ALS_CTRL		0
+#define LM3532_LINEAR_MAP	BIT(1)
+#define LM3532_ZONE_MASK	(BIT(2) | BIT(3) | BIT(4))
+#define LM3532_ZONE_0		0
+#define LM3532_ZONE_1		BIT(2)
+#define LM3532_ZONE_2		BIT(3)
+#define LM3532_ZONE_3		(BIT(2) | BIT(3))
+#define LM3532_ZONE_4		BIT(4)
+
+#define LM3532_ENABLE_ALS	BIT(3)
+#define LM3532_ALS_SEL_SHIFT	6
+
+/* Zone Boundary Register */
+#define LM3532_ALS_WINDOW_mV	2000
+#define LM3532_ALS_ZB_MAX	4
+#define LM3532_ALS_OFFSET_mV	2
+
+#define LM3532_CONTROL_A	0
+#define LM3532_CONTROL_B	1
+#define LM3532_CONTROL_C	2
+#define LM3532_MAX_CONTROL_BANKS 3
+#define LM3532_MAX_LED_STRINGS	3
+
+#define LM3532_OUTPUT_CFG_MASK	0x3
+#define LM3532_BRT_VAL_ADJUST	8
+#define LM3532_RAMP_DOWN_SHIFT	3
+
+#define LM3532_NUM_RAMP_VALS	8
+#define LM3532_NUM_AVG_VALS	8
+#define LM3532_NUM_IMP_VALS	32
+
+/*
+ * struct lm3532_als_data
+ * @config - value of ALS configuration register
+ * @als1_imp_sel - value of ALS1 resistor select register
+ * @als2_imp_sel - value of ALS2 resistor select register
+ * @als_avrg_time - ALS averaging time
+ * @als_input_mode - ALS input mode for brightness control
+ * @als_vmin - Minimum ALS voltage
+ * @als_vmax - Maximum ALS voltage
+ * @zone_lo - values of ALS lo ZB(Zone Boundary) registers
+ * @zone_hi - values of ALS hi ZB(Zone Boundary) registers
+ */
+struct lm3532_als_data {
+	u8 config;
+	u8 als1_imp_sel;
+	u8 als2_imp_sel;
+	u8 als_avrg_time;
+	u8 als_input_mode;
+	u32 als_vmin;
+	u32 als_vmax;
+	u8 zones_lo[LM3532_ALS_ZB_MAX];
+	u8 zones_hi[LM3532_ALS_ZB_MAX];
+};
+
+/**
+ * struct lm3532_led
+ * @led_dev: led class device
+ * @priv - Pointer the device data structure
+ * @control_bank - Control bank the LED is associated to
+ * @mode - Mode of the LED string
+ * @num_leds - Number of LED strings are supported in this array
+ * @led_strings - The LED strings supported in this array
+ * @label - LED label
+ */
+struct lm3532_led {
+	struct led_classdev led_dev;
+	struct lm3532_data *priv;
+
+	int control_bank;
+	int mode;
+	int num_leds;
+	u32 led_strings[LM3532_MAX_CONTROL_BANKS];
+	char label[LED_MAX_NAME_SIZE];
+};
+
+/**
+ * struct lm3532_data
+ * @enable_gpio - Hardware enable gpio
+ * @regulator: regulator
+ * @client: i2c client
+ * @regmap - Devices register map
+ * @dev - Pointer to the devices device struct
+ * @lock - Lock for reading/writing the device
+ * @als_data - Pointer to the als data struct
+ * @runtime_ramp_up - Runtime ramp up setting
+ * @runtime_ramp_down - Runtime ramp down setting
+ * @leds - Array of LED strings
+ */
+struct lm3532_data {
+	struct gpio_desc *enable_gpio;
+	struct regulator *regulator;
+	struct i2c_client *client;
+	struct regmap *regmap;
+	struct device *dev;
+	struct mutex lock;
+
+	struct lm3532_als_data *als_data;
+
+	u32 runtime_ramp_up;
+	u32 runtime_ramp_down;
+
+	struct lm3532_led leds[];
+};
+
+static const struct reg_default lm3532_reg_defs[] = {
+	{LM3532_REG_OUTPUT_CFG, 0xe4},
+	{LM3532_REG_STARTSHUT_RAMP, 0xc0},
+	{LM3532_REG_RT_RAMP, 0xc0},
+	{LM3532_REG_PWM_A_CFG, 0x82},
+	{LM3532_REG_PWM_B_CFG, 0x82},
+	{LM3532_REG_PWM_C_CFG, 0x82},
+	{LM3532_REG_ZONE_CFG_A, 0xf1},
+	{LM3532_REG_CTRL_A_BRT, 0xf3},
+	{LM3532_REG_ZONE_CFG_B, 0xf1},
+	{LM3532_REG_CTRL_B_BRT, 0xf3},
+	{LM3532_REG_ZONE_CFG_C, 0xf1},
+	{LM3532_REG_CTRL_C_BRT, 0xf3},
+	{LM3532_REG_ENABLE, 0xf8},
+	{LM3532_ALS_CONFIG, 0x44},
+	{LM3532_REG_ZN_0_HI, 0x35},
+	{LM3532_REG_ZN_0_LO, 0x33},
+	{LM3532_REG_ZN_1_HI, 0x6a},
+	{LM3532_REG_ZN_1_LO, 0x66},
+	{LM3532_REG_ZN_2_HI, 0xa1},
+	{LM3532_REG_ZN_2_LO, 0x99},
+	{LM3532_REG_ZN_3_HI, 0xdc},
+	{LM3532_REG_ZN_3_LO, 0xcc},
+};
+
+static const struct regmap_config lm3532_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+
+	.max_register = LM3532_REG_MAX,
+	.reg_defaults = lm3532_reg_defs,
+	.num_reg_defaults = ARRAY_SIZE(lm3532_reg_defs),
+	.cache_type = REGCACHE_FLAT,
+};
+
+const static int als_imp_table[LM3532_NUM_IMP_VALS] = {37000, 18500, 12330,
+						       92500, 7400, 6170, 5290,
+						       4630, 4110, 3700, 3360,
+						       3080, 2850, 2640, 2440,
+						       2310, 2180, 2060, 1950,
+						       1850, 1760, 1680, 1610,
+						       1540, 1480, 1420, 1370,
+						       1320, 1280, 1230, 1190};
+static int lm3532_get_als_imp_index(int als_imped)
+{
+	int i;
+
+	if (als_imped > als_imp_table[1])
+		return 0;
+
+	if (als_imped < als_imp_table[LM3532_NUM_IMP_VALS - 1])
+		return LM3532_NUM_IMP_VALS - 1;
+
+	for (i = 1; i < LM3532_NUM_IMP_VALS; i++) {
+		if (als_imped == als_imp_table[i])
+			return i;
+
+		/* Find an approximate index by looking up the table */
+		if (als_imped < als_imp_table[i - 1] &&
+		    als_imped > als_imp_table[i]) {
+			if (als_imped - als_imp_table[i - 1] <
+			    als_imp_table[i] - als_imped)
+				return i + 1;
+			else
+				return i;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int lm3532_get_index(const int table[], int size, int value)
+{
+	int i;
+
+	for (i = 1; i < size; i++) {
+		if (value == table[i])
+			return i;
+
+		/* Find an approximate index by looking up the table */
+		if (value > table[i - 1] &&
+		    value < table[i]) {
+			if (value - table[i - 1] < table[i] - value)
+				return i - 1;
+			else
+				return i;
+		}
+	}
+
+	return -EINVAL;
+}
+
+const static int als_avrg_table[LM3532_NUM_AVG_VALS] = {17920, 35840, 71680,
+							1433360, 286720, 573440,
+							1146880, 2293760};
+static int lm3532_get_als_avg_index(int avg_time)
+{
+	if (avg_time <= als_avrg_table[0])
+		return 0;
+
+	if (avg_time > als_avrg_table[LM3532_NUM_AVG_VALS - 1])
+		return LM3532_NUM_AVG_VALS - 1;
+
+	return lm3532_get_index(&als_avrg_table[0], LM3532_NUM_AVG_VALS,
+				avg_time);
+}
+
+const static int ramp_table[LM3532_NUM_RAMP_VALS] = { 8, 1024, 2048, 4096, 8192,
+						     16384, 32768, 65536};
+static int lm3532_get_ramp_index(int ramp_time)
+{
+	if (ramp_time <= ramp_table[0])
+		return 0;
+
+	if (ramp_time > ramp_table[LM3532_NUM_RAMP_VALS - 1])
+		return LM3532_NUM_RAMP_VALS - 1;
+
+	return lm3532_get_index(&ramp_table[0], LM3532_NUM_RAMP_VALS,
+				ramp_time);
+}
+
+static int lm3532_led_enable(struct lm3532_led *led_data)
+{
+	int ctrl_en_val = BIT(led_data->control_bank);
+	int ret;
+
+	ret = regmap_update_bits(led_data->priv->regmap, LM3532_REG_ENABLE,
+					 ctrl_en_val, ctrl_en_val);
+	if (ret) {
+		dev_err(led_data->priv->dev, "Failed to set ctrl:%d\n", ret);
+		return ret;
+	}
+
+	return regulator_enable(led_data->priv->regulator);
+}
+
+static int lm3532_led_disable(struct lm3532_led *led_data)
+{
+	int ctrl_en_val = BIT(led_data->control_bank);
+	int ret;
+
+	ret = regmap_update_bits(led_data->priv->regmap, LM3532_REG_ENABLE,
+					 ctrl_en_val, ~ctrl_en_val);
+	if (ret) {
+		dev_err(led_data->priv->dev, "Failed to set ctrl:%d\n", ret);
+		return ret;
+	}
+
+	return regulator_disable(led_data->priv->regulator);
+}
+
+static int lm3532_brightness_set(struct led_classdev *led_cdev,
+				 enum led_brightness brt_val)
+{
+	struct lm3532_led *led =
+			container_of(led_cdev, struct lm3532_led, led_dev);
+	u8 brightness_reg;
+	int ret;
+
+	mutex_lock(&led->priv->lock);
+
+	if (led->mode == LM3532_BL_MODE_ALS) {
+		if (brt_val > LED_OFF)
+			ret = lm3532_led_enable(led);
+		else
+			ret = lm3532_led_disable(led);
+
+		goto unlock;
+	}
+
+	if (brt_val == LED_OFF) {
+		ret = lm3532_led_disable(led);
+		goto unlock;
+	}
+
+	ret = lm3532_led_enable(led);
+	if (ret)
+		goto unlock;
+
+	brightness_reg = LM3532_REG_CTRL_A_BRT + led->control_bank * 2;
+	brt_val = brt_val / LM3532_BRT_VAL_ADJUST;
+
+	ret = regmap_write(led->priv->regmap, brightness_reg, brt_val);
+
+unlock:
+	mutex_unlock(&led->priv->lock);
+	return ret;
+}
+
+static int lm3532_init_registers(struct lm3532_led *led)
+{
+	struct lm3532_data *drvdata = led->priv;
+	unsigned int runtime_ramp_val;
+	unsigned int output_cfg_val = 0;
+	unsigned int output_cfg_shift = 0;
+	unsigned int output_cfg_mask = 0;
+	int ret, i;
+
+	for (i = 0; i < led->num_leds; i++) {
+		output_cfg_shift = led->led_strings[i] * 2;
+		output_cfg_val |= (led->control_bank << output_cfg_shift);
+		output_cfg_mask |= LM3532_OUTPUT_CFG_MASK << output_cfg_shift;
+	}
+
+	ret = regmap_update_bits(drvdata->regmap, LM3532_REG_OUTPUT_CFG,
+				 output_cfg_mask, output_cfg_val);
+	if (ret)
+		return ret;
+
+	runtime_ramp_val = drvdata->runtime_ramp_up |
+			 (drvdata->runtime_ramp_down << LM3532_RAMP_DOWN_SHIFT);
+
+	return regmap_write(drvdata->regmap, LM3532_REG_RT_RAMP,
+			    runtime_ramp_val);
+}
+
+static int lm3532_als_configure(struct lm3532_data *priv,
+				struct lm3532_led *led)
+{
+	struct lm3532_als_data *als = priv->als_data;
+	u32 als_vmin, als_vmax, als_vstep;
+	int zone_reg = LM3532_REG_ZN_0_HI;
+	int brightnes_config_reg;
+	int ret;
+	int i;
+
+	als_vmin = als->als_vmin;
+	als_vmax = als->als_vmax;
+
+	als_vstep = (als_vmax - als_vmin) / ((LM3532_ALS_ZB_MAX + 1) * 2);
+
+	for (i = 0; i < LM3532_ALS_ZB_MAX; i++) {
+		als->zones_lo[i] = ((als_vmin + als_vstep + (i * als_vstep)) *
+				LED_FULL) / 1000;
+		als->zones_hi[i] = ((als_vmin + LM3532_ALS_OFFSET_mV +
+				als_vstep + (i * als_vstep)) * LED_FULL) / 1000;
+
+		zone_reg = LM3532_REG_ZN_0_HI + i * 2;
+		ret = regmap_write(priv->regmap, zone_reg, als->zones_lo[i]);
+		if (ret)
+			return ret;
+
+		zone_reg += 1;
+		ret = regmap_write(priv->regmap, zone_reg, als->zones_hi[i]);
+		if (ret)
+			return ret;
+	}
+
+	als->config = (als->als_avrg_time | (LM3532_ENABLE_ALS) |
+		(als->als_input_mode << LM3532_ALS_SEL_SHIFT));
+
+	ret = regmap_write(priv->regmap, LM3532_ALS_CONFIG, als->config);
+	if (ret)
+		return ret;
+
+	brightnes_config_reg = LM3532_REG_ZONE_CFG_A + led->control_bank * 2;
+
+	return regmap_update_bits(priv->regmap, brightnes_config_reg,
+				  LM3532_I2C_CTRL, LM3532_ALS_CTRL);
+}
+
+static int lm3532_parse_als(struct lm3532_data *priv)
+{
+	struct lm3532_als_data *als;
+	int als_avg_time;
+	int als_impedance;
+	int ret;
+
+	als = devm_kzalloc(priv->dev, sizeof(*als), GFP_KERNEL);
+	if (als == NULL)
+		return -ENOMEM;
+
+	ret = device_property_read_u32(&priv->client->dev, "ti,als-vmin",
+				       &als->als_vmin);
+	if (ret)
+		als->als_vmin = 0;
+
+	ret = device_property_read_u32(&priv->client->dev, "ti,als-vmax",
+				       &als->als_vmax);
+	if (ret)
+		als->als_vmax = LM3532_ALS_WINDOW_mV;
+
+	if (als->als_vmax > LM3532_ALS_WINDOW_mV) {
+		ret = -EINVAL;
+		return ret;
+	}
+
+	ret = device_property_read_u32(&priv->client->dev, "ti,als1-imp-sel",
+				      &als_impedance);
+	if (ret)
+		als->als1_imp_sel = 0;
+	else
+		als->als1_imp_sel = lm3532_get_als_imp_index(als_impedance);
+
+	ret = device_property_read_u32(&priv->client->dev, "ti,als2-imp-sel",
+				      &als_impedance);
+	if (ret)
+		als->als2_imp_sel = 0;
+	else
+		als->als2_imp_sel = lm3532_get_als_imp_index(als_impedance);
+
+	ret = device_property_read_u32(&priv->client->dev, "ti,als-avrg-time-us",
+				      &als_avg_time);
+	if (ret)
+		als->als_avrg_time = 0;
+	else
+		als->als_avrg_time = lm3532_get_als_avg_index(als_avg_time);
+
+	ret = device_property_read_u8(&priv->client->dev, "ti,als-input-mode",
+				      &als->als_input_mode);
+	if (ret)
+		als->als_input_mode = 0;
+
+	if (als->als_input_mode > LM3532_BL_MODE_ALS) {
+		ret = -EINVAL;
+		return ret;
+	}
+
+	priv->als_data = als;
+
+	return ret;
+}
+
+static int lm3532_parse_node(struct lm3532_data *priv)
+{
+	struct fwnode_handle *child = NULL;
+	struct lm3532_led *led;
+	const char *name;
+	int control_bank;
+	u32 ramp_time;
+	size_t i = 0;
+	int ret;
+
+	priv->enable_gpio = devm_gpiod_get_optional(&priv->client->dev,
+						   "enable", GPIOD_OUT_LOW);
+	if (IS_ERR(priv->enable_gpio))
+		priv->enable_gpio = NULL;
+
+	priv->regulator = devm_regulator_get(&priv->client->dev, "vin");
+	if (IS_ERR(priv->regulator))
+		priv->regulator = NULL;
+
+	ret = device_property_read_u32(&priv->client->dev, "ramp-up-us",
+				       &ramp_time);
+	if (ret)
+		dev_info(&priv->client->dev, "ramp-up-ms property missing\n");
+	else
+		priv->runtime_ramp_up = lm3532_get_ramp_index(ramp_time);
+
+	ret = device_property_read_u32(&priv->client->dev, "ramp-down-us",
+				       &ramp_time);
+	if (ret)
+		dev_info(&priv->client->dev, "ramp-down-ms property missing\n");
+	else
+		priv->runtime_ramp_down = lm3532_get_ramp_index(ramp_time);
+
+	device_for_each_child_node(priv->dev, child) {
+		led = &priv->leds[i];
+
+		ret = fwnode_property_read_u32(child, "reg", &control_bank);
+		if (ret) {
+			dev_err(&priv->client->dev, "reg property missing\n");
+			fwnode_handle_put(child);
+			goto child_out;
+		}
+
+		if (control_bank > LM3532_CONTROL_C) {
+			dev_err(&priv->client->dev, "Control bank invalid\n");
+			continue;
+		}
+
+		led->control_bank = control_bank;
+
+		ret = fwnode_property_read_u32(child, "ti,led-mode",
+					       &led->mode);
+		if (ret) {
+			dev_err(&priv->client->dev, "ti,led-mode property missing\n");
+			fwnode_handle_put(child);
+			goto child_out;
+		}
+
+		if (led->mode == LM3532_BL_MODE_ALS) {
+			ret = lm3532_parse_als(priv);
+			if (ret)
+				dev_err(&priv->client->dev, "Failed to parse als\n");
+			else
+				lm3532_als_configure(priv, led);
+		}
+
+		led->num_leds = fwnode_property_read_u32_array(child,
+							       "led-sources",
+							       NULL, 0);
+
+		if (led->num_leds > LM3532_MAX_LED_STRINGS) {
+			dev_err(&priv->client->dev, "To many LED string defined\n");
+			continue;
+		}
+
+		ret = fwnode_property_read_u32_array(child, "led-sources",
+						    led->led_strings,
+						    led->num_leds);
+		if (ret) {
+			dev_err(&priv->client->dev, "led-sources property missing\n");
+			fwnode_handle_put(child);
+			goto child_out;
+		}
+
+		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::", priv->client->name);
+		else
+			snprintf(led->label, sizeof(led->label),
+				 "%s:%s", priv->client->name, name);
+
+		led->priv = priv;
+		led->led_dev.name = led->label;
+		led->led_dev.brightness_set_blocking = lm3532_brightness_set;
+
+		ret = devm_led_classdev_register(priv->dev, &led->led_dev);
+		if (ret) {
+			dev_err(&priv->client->dev, "led register err: %d\n",
+				ret);
+			fwnode_handle_put(child);
+			goto child_out;
+		}
+
+		lm3532_init_registers(led);
+
+		i++;
+	}
+
+child_out:
+	return ret;
+}
+
+static int lm3532_probe(struct i2c_client *client,
+			   const struct i2c_device_id *id)
+{
+	struct lm3532_data *drvdata;
+	int ret = 0;
+	int count;
+
+	count = device_get_child_node_count(&client->dev);
+	if (!count) {
+		dev_err(&client->dev, "LEDs are not defined in device tree!");
+		return -ENODEV;
+	}
+
+	drvdata = devm_kzalloc(&client->dev, struct_size(drvdata, leds, count),
+			   GFP_KERNEL);
+	if (drvdata == NULL)
+		return -ENOMEM;
+
+	drvdata->client = client;
+	drvdata->dev = &client->dev;
+
+	drvdata->regmap = devm_regmap_init_i2c(client, &lm3532_regmap_config);
+	if (IS_ERR(drvdata->regmap)) {
+		ret = PTR_ERR(drvdata->regmap);
+		dev_err(&client->dev, "Failed to allocate register map: %d\n",
+			ret);
+		return ret;
+	}
+
+	mutex_init(&drvdata->lock);
+	i2c_set_clientdata(client, drvdata);
+
+	ret = lm3532_parse_node(drvdata);
+	if (ret) {
+		dev_err(&client->dev, "Failed to parse node\n");
+		return ret;
+	}
+
+	if (drvdata->enable_gpio)
+		gpiod_direction_output(drvdata->enable_gpio, 1);
+
+	return ret;
+}
+
+static int lm3532_remove(struct i2c_client *client)
+{
+	struct lm3532_data *drvdata = i2c_get_clientdata(client);
+
+	if (drvdata->enable_gpio)
+		gpiod_direction_output(drvdata->enable_gpio, 0);
+
+	return 0;
+}
+
+static const struct of_device_id of_lm3532_leds_match[] = {
+	{ .compatible = "ti,lm3532", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, of_lm3532_leds_match);
+
+static const struct i2c_device_id lm3532_id[] = {
+	{LM3532_NAME, 0},
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, lm3532_id);
+
+static struct i2c_driver lm3532_i2c_driver = {
+	.probe = lm3532_probe,
+	.remove = lm3532_remove,
+	.id_table = lm3532_id,
+	.driver = {
+		.name = LM3532_NAME,
+		.of_match_table = of_lm3532_leds_match,
+	},
+};
+module_i2c_driver(lm3532_i2c_driver);
+
+MODULE_DESCRIPTION("Back Light driver for LM3532");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");