[PATCH v3 1/2] dt-bindings: leds: Add bindings for lm3697 driver

[PATCH v3 1/2] dt-bindings: leds: Add bindings for lm3697 driver

[Dan Murphy]

Add the device tree bindings for the lm3697
LED driver for backlighting and display.

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

v3 - Updated subject with prefered title - https://lore.kernel.org/patchwork/patch/972337/
v2 - Fixed subject and patch commit message - https://lore.kernel.org/patchwork/patch/971326/

 .../devicetree/bindings/leds/leds-lm3697.txt  | 89 +++++++++++++++++++
 1 file changed, 89 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/leds-lm3697.txt

diff --git a/Documentation/devicetree/bindings/leds/leds-lm3697.txt b/Documentation/devicetree/bindings/leds/leds-lm3697.txt
new file mode 100644
index 000000000000..34403a48a0ce
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/leds-lm3697.txt
@@ -0,0 +1,89 @@
+* Texas Instruments - LM3697 Highly Efficient White LED Driver
+
+The LM3697 11-bit LED driver provides high-
+performance backlight dimming for 1, 2, or 3 series
+LED strings while delivering up to 90% efficiency.
+
+This device is suitable for Display and Keypad Lighting
+
+Required properties:
+	- compatible:
+		"ti,lm3967"
+	- reg :  I2C slave address
+	- #address-cells : 1
+	- #size-cells : 0
+
+Optional properties:
+	- enable-gpios : gpio pin to enable/disable the device.
+	- vled-supply : LED supply
+
+Required child properties:
+	- reg : 0 - LED is Controlled by bank A
+		1 - LED is Controlled by bank B
+	- led-sources - Indicates which HVLED string is associated to which
+			control bank.  The HVLED string cannot be associated with
+			two control banks.  This property is an array of 3 and
+			all positions in the array must be populated.
+			Additional information is contained
+			in Documentation/devicetree/bindings/leds/common.txt
+			0 - End of array if all 3 LEDs are not declared for a
+			    single control bank.
+			1 - HVLED 1 string
+			2 - HVLED 2 string
+			3 - HVLED 3 string
+
+Optional child properties:
+	- label : see Documentation/devicetree/bindings/leds/common.txt
+	- linux,default-trigger :
+	   see Documentation/devicetree/bindings/leds/common.txt
+
+Example:
+
+HVLED string 1 and 2 controlled by control bank A and HVLED string controlled by
+control bank B.
+
+led-controller@36 {
+	compatible = "ti,lm3967";
+	reg = <0x36>;
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	enable-gpios = <&gpio1 28 GPIO_ACTIVE_HIGH>;
+	vled-supply = <&vbatt>;
+
+	led@0 {
+		reg = <0>;
+		led-sources = <0x1 0x2 0x0>;
+		label = "white:first_backlight_cluster";
+		linux,default-trigger = "backlight";
+	};
+
+	led@1 {
+		reg = <1>;
+		led-sources = <0x3 0x0 0x0>;
+		label = "white:second_backlight_cluster";
+		linux,default-trigger = "backlight";
+	};
+}
+
+All HVLED strings controlled by control bank A
+
+led-controller@36 {
+	compatible = "ti,lm3967";
+	reg = <0x36>;
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	enable-gpios = <&gpio1 28 GPIO_ACTIVE_HIGH>;
+	vled-supply = <&vbatt>;
+
+	led@0 {
+		reg = <0>;
+		led-sources = <0x1 0x2 0x3>;
+		label = "white:backlight_cluster";
+		linux,default-trigger = "backlight";
+	};
+}
+
+For more product information please see the link below:
+http://www.ti.com/lit/ds/symlink/lm3697.pdf
-- 
2.17.0.582.gccdcbd54c

[PATCH v3 2/2] leds: lm3697: Introduce the lm3697 driver

[Dan Murphy]

Introduce the lm3697 LED driver for
backlighting and display.

Datasheet location:
http://www.ti.com/lit/ds/symlink/lm3697.pdf

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

v3 - Add code to support led-sources and control bank configuration also fix
other miscellaneous issues reported- https://lore.kernel.org/patchwork/patch/972336/
v2 - Removed unneed 'of' calls in dt_parse, fixed comment, fixed checkpatch
error, and change led registration - https://lore.kernel.org/patchwork/patch/971327/

 drivers/leds/Kconfig       |   9 +
 drivers/leds/Makefile      |   1 +
 drivers/leds/leds-lm3697.c | 403 +++++++++++++++++++++++++++++++++++++
 3 files changed, 413 insertions(+)
 create mode 100644 drivers/leds/leds-lm3697.c

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 44097a3e0fcc..784cbe375724 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -151,6 +151,15 @@ config LEDS_LM3642
 	  converter plus 1.5A constant current driver for a high-current
 	  white LED.
 
+config LEDS_LM3697
+	tristate "LED support for LM3697 Chip"
+	depends on LEDS_CLASS && I2C
+	select REGMAP_I2C
+	help
+	  This option enables support for LEDs connected to LM3697.
+	  The LM3697 is an 11 bit high performance backlight driver for
+	  keypad and display lighting.
+
 config LEDS_LM3692X
 	tristate "LED support for LM3692x Chips"
 	depends on LEDS_CLASS && I2C && OF
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 420b5d2cfa62..2813f089f3db 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -19,6 +19,7 @@ obj-$(CONFIG_LEDS_LOCOMO)		+= leds-locomo.o
 obj-$(CONFIG_LEDS_LM3530)		+= leds-lm3530.o
 obj-$(CONFIG_LEDS_LM3533)		+= leds-lm3533.o
 obj-$(CONFIG_LEDS_LM3642)		+= leds-lm3642.o
+obj-$(CONFIG_LEDS_LM3697)		+= leds-lm3697.o
 obj-$(CONFIG_LEDS_MIKROTIK_RB532)	+= leds-rb532.o
 obj-$(CONFIG_LEDS_S3C24XX)		+= leds-s3c24xx.o
 obj-$(CONFIG_LEDS_NET48XX)		+= leds-net48xx.o
diff --git a/drivers/leds/leds-lm3697.c b/drivers/leds/leds-lm3697.c
new file mode 100644
index 000000000000..33205040c4f9
--- /dev/null
+++ b/drivers/leds/leds-lm3697.c
@@ -0,0 +1,403 @@
+// SPDX-License-Identifier: GPL-2.0
+// TI LM3697 LED chip family driver
+// Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
+
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+#include <uapi/linux/uleds.h>
+
+#define LM3697_REV			0x0
+#define LM3697_RESET			0x1
+#define LM3697_OUTPUT_CONFIG		0x10
+#define LM3697_CTRL_A_RAMP		0x11
+#define LM3697_CTRL_B_RAMP		0x12
+#define LM3697_CTRL_A_B_RT_RAMP		0x13
+#define LM3697_CTRL_A_B_RAMP_CFG	0x14
+#define LM3697_CTRL_A_B_BRT_CFG		0x16
+#define LM3697_CTRL_A_FS_CURR_CFG	0x17
+#define LM3697_CTRL_B_FS_CURR_CFG	0x18
+#define LM3697_PWM_CFG			0x1c
+#define LM3697_CTRL_A_BRT_LSB		0x20
+#define LM3697_CTRL_A_BRT_MSB		0x21
+#define LM3697_CTRL_B_BRT_LSB		0x22
+#define LM3697_CTRL_B_BRT_MSB		0x23
+#define LM3697_CTRL_ENABLE		0x24
+
+#define LM3697_SW_RESET		BIT(0)
+
+#define LM3697_CTRL_A_EN	BIT(0)
+#define LM3697_CTRL_B_EN	BIT(1)
+#define LM3697_CTRL_A_B_EN	(LM3697_CTRL_A_EN | LM3697_CTRL_B_EN)
+
+#define LM3697_MAX_LED_STRINGS	3
+
+#define LM3697_CONTROL_A	0
+#define LM3697_CONTROL_B	1
+
+#define LM3697_END_OF_ARRAY	0
+#define LM3697_HVLED1	1
+#define LM3697_HVLED2	2
+#define LM3697_HVLED3	3
+
+#define LM3697_HVLED1_SHIFT	0
+#define LM3697_HVLED2_SHIFT	1
+#define LM3697_HVLED3_SHIFT	2
+
+/**
+ * struct lm3697_led -
+ * @hvled_strings - Array of LED strings associated with a control bank
+ * @label - LED label
+ * @led_dev - LED class device
+ * @priv - Pointer to the device struct
+ * @control_bank - Control bank the LED is associated to. 0 is control bank A
+ *		   1 is control bank B.
+ */
+struct lm3697_led {
+	u32 hvled_strings[LM3697_MAX_LED_STRINGS];
+	char label[LED_MAX_NAME_SIZE];
+	struct led_classdev led_dev;
+	struct lm3697 *priv;
+	int control_bank;
+};
+
+/**
+ * struct lm3697 -
+ * @enable_gpio - Hardware enable gpio
+ * @regulator - LED supply regulator pointer
+ * @client - Pointer to the I2C client
+ * @regmap - Devices register map
+ * @dev - Pointer to the devices device struct
+ * @lock - Lock for reading/writing the device
+ * @leds - Array of LED strings.
+ */
+struct lm3697 {
+	struct gpio_desc *enable_gpio;
+	struct regulator *regulator;
+	struct i2c_client *client;
+	struct regmap *regmap;
+	struct device *dev;
+	struct mutex lock;
+	struct lm3697_led leds[];
+};
+
+static const struct reg_default lm3697_reg_defs[] = {
+	{LM3697_OUTPUT_CONFIG, 0x6},
+	{LM3697_CTRL_A_RAMP, 0x0},
+	{LM3697_CTRL_B_RAMP, 0x0},
+	{LM3697_CTRL_A_B_RT_RAMP, 0x0},
+	{LM3697_CTRL_A_B_RAMP_CFG, 0x0},
+	{LM3697_CTRL_A_B_BRT_CFG, 0x0},
+	{LM3697_CTRL_A_FS_CURR_CFG, 0x13},
+	{LM3697_CTRL_B_FS_CURR_CFG, 0x13},
+	{LM3697_PWM_CFG, 0xc},
+	{LM3697_CTRL_A_BRT_LSB, 0x0},
+	{LM3697_CTRL_A_BRT_MSB, 0x0},
+	{LM3697_CTRL_B_BRT_LSB, 0x0},
+	{LM3697_CTRL_B_BRT_MSB, 0x0},
+	{LM3697_CTRL_ENABLE, 0x0},
+};
+
+static const struct regmap_config lm3697_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+
+	.max_register = LM3697_CTRL_ENABLE,
+	.reg_defaults = lm3697_reg_defs,
+	.num_reg_defaults = ARRAY_SIZE(lm3697_reg_defs),
+	.cache_type = REGCACHE_FLAT,
+};
+
+static int lm3697_brightness_set(struct led_classdev *led_cdev,
+				enum led_brightness brt_val)
+{
+	struct lm3697_led *led = container_of(led_cdev, struct lm3697_led,
+					      led_dev);
+	int brt_msb_reg, brt_lsb_reg, ctrl_en_val;
+	int led_brightness_lsb = (brt_val >> 5);
+	int ret;
+
+	mutex_lock(&led->priv->lock);
+
+	if (led->control_bank == LM3697_CONTROL_A) {
+		brt_msb_reg = LM3697_CTRL_A_BRT_MSB;
+		brt_lsb_reg = LM3697_CTRL_A_BRT_LSB;
+		ctrl_en_val = LM3697_CTRL_A_EN;
+	} else {
+		brt_msb_reg = LM3697_CTRL_B_BRT_MSB;
+		brt_lsb_reg = LM3697_CTRL_B_BRT_LSB;
+		ctrl_en_val = LM3697_CTRL_B_EN;
+	}
+
+	if (brt_val == LED_OFF)
+		ret = regmap_update_bits(led->priv->regmap, LM3697_CTRL_ENABLE,
+					 ctrl_en_val, ~ctrl_en_val);
+	else
+		ret = regmap_update_bits(led->priv->regmap, LM3697_CTRL_ENABLE,
+					 ctrl_en_val, ctrl_en_val);
+
+	if (ret) {
+		dev_err(&led->priv->client->dev, "Cannot write CTRL enable\n");
+		goto out;
+	}
+
+	ret = regmap_write(led->priv->regmap, brt_lsb_reg, led_brightness_lsb);
+	if (ret) {
+		dev_err(&led->priv->client->dev, "Cannot write LSB\n");
+		goto out;
+	}
+
+	ret = regmap_write(led->priv->regmap, brt_msb_reg, brt_val);
+	if (ret) {
+		dev_err(&led->priv->client->dev, "Cannot write MSB\n");
+		goto out;
+	}
+out:
+	mutex_unlock(&led->priv->lock);
+	return ret;
+}
+
+static int lm3697_set_control_bank(struct lm3697 *priv)
+{
+	u8 control_bank_config = 0;
+	struct lm3697_led *led;
+	int ret, i;
+
+	led = &priv->leds[0];
+	if (led->control_bank == LM3697_CONTROL_A)
+		led = &priv->leds[1];
+
+	if (led->control_bank == LM3697_CONTROL_B &&
+	    led->hvled_strings[0] == LM3697_END_OF_ARRAY)
+		goto write_config;
+
+	for (i = 0; i < LM3697_MAX_LED_STRINGS; i++) {
+		if (led->hvled_strings[i] == LM3697_END_OF_ARRAY)
+			break;
+
+		if (led->hvled_strings[i] == LM3697_HVLED1)
+			control_bank_config |= 1 << LM3697_HVLED1_SHIFT;
+
+		if (led->hvled_strings[i] == LM3697_HVLED2)
+			control_bank_config |= 1 << LM3697_HVLED2_SHIFT;
+
+		if (led->hvled_strings[i] == LM3697_HVLED3)
+			control_bank_config |= 1 << LM3697_HVLED3_SHIFT;
+	}
+
+write_config:
+	ret = regmap_write(priv->regmap, LM3697_OUTPUT_CONFIG,
+			   control_bank_config);
+	if (ret)
+		dev_err(&priv->client->dev, "Cannot write OUTPUT config\n");
+
+	return ret;
+}
+
+static int lm3697_init(struct lm3697 *priv)
+{
+	int ret;
+
+	if (priv->enable_gpio) {
+		gpiod_direction_output(priv->enable_gpio, 1);
+	} else {
+		ret = regmap_write(priv->regmap, LM3697_RESET, LM3697_SW_RESET);
+		if (ret) {
+			dev_err(&priv->client->dev, "Cannot reset the device\n");
+			goto out;
+		}
+	}
+
+	ret = regmap_write(priv->regmap, LM3697_CTRL_ENABLE, 0x0);
+	if (ret) {
+		dev_err(&priv->client->dev, "Cannot write ctrl enable\n");
+		goto out;
+	}
+
+	ret = lm3697_set_control_bank(priv);
+	if (ret)
+		dev_err(&priv->client->dev, "Setting the CRTL bank failed\n");
+
+out:
+	return ret;
+}
+
+static int lm3697_probe_dt(struct lm3697 *priv)
+{
+	struct fwnode_handle *child = NULL;
+	struct lm3697_led *led;
+	const char *name;
+	int control_bank;
+	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)) {
+		ret = PTR_ERR(priv->enable_gpio);
+		dev_err(&priv->client->dev, "Failed to get enable gpio: %d\n",
+			ret);
+		return ret;
+	}
+
+	priv->regulator = devm_regulator_get(&priv->client->dev, "vled");
+	if (IS_ERR(priv->regulator))
+		priv->regulator = NULL;
+
+	device_for_each_child_node(priv->dev, child) {
+		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 > LM3697_CONTROL_B) {
+			dev_err(&priv->client->dev, "reg property is invalid\n");
+			ret = -EINVAL;
+			fwnode_handle_put(child);
+			goto child_out;
+		}
+
+		led = &priv->leds[i];
+		led->control_bank = control_bank;
+		ret = fwnode_property_read_u32_array(child, "led-sources",
+						    led->hvled_strings,
+						    LM3697_MAX_LED_STRINGS);
+		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 = lm3697_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;
+		}
+
+		i++;
+	}
+
+child_out:
+	return ret;
+}
+
+static int lm3697_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+	struct lm3697 *led;
+	int count;
+	int ret;
+
+	count = device_get_child_node_count(&client->dev);
+	if (!count) {
+		dev_err(&client->dev, "LEDs are not defined in device tree!");
+		return -ENODEV;
+	}
+
+	led = devm_kzalloc(&client->dev, struct_size(led, leds, count),
+			   GFP_KERNEL);
+	if (!led)
+		return -ENOMEM;
+
+	mutex_init(&led->lock);
+	i2c_set_clientdata(client, led);
+
+	led->client = client;
+	led->dev = &client->dev;
+	led->regmap = devm_regmap_init_i2c(client, &lm3697_regmap_config);
+	if (IS_ERR(led->regmap)) {
+		ret = PTR_ERR(led->regmap);
+		dev_err(&client->dev, "Failed to allocate register map: %d\n",
+			ret);
+		return ret;
+	}
+
+	ret = lm3697_probe_dt(led);
+	if (ret)
+		return ret;
+
+	ret = lm3697_init(led);
+
+	return ret;
+}
+
+static int lm3697_remove(struct i2c_client *client)
+{
+	struct lm3697 *led = i2c_get_clientdata(client);
+	int ret;
+
+	ret = regmap_update_bits(led->regmap, LM3697_CTRL_ENABLE,
+				 LM3697_CTRL_A_B_EN, 0);
+	if (ret) {
+		dev_err(&led->client->dev, "Failed to disable the device\n");
+		return ret;
+	}
+
+	if (led->enable_gpio)
+		gpiod_direction_output(led->enable_gpio, 0);
+
+	if (led->regulator) {
+		ret = regulator_disable(led->regulator);
+		if (ret)
+			dev_err(&led->client->dev,
+				"Failed to disable regulator\n");
+	}
+
+	mutex_destroy(&led->lock);
+
+	return 0;
+}
+
+static const struct i2c_device_id lm3697_id[] = {
+	{ "lm3697", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, lm3697_id);
+
+static const struct of_device_id of_lm3697_leds_match[] = {
+	{ .compatible = "ti,lm3697", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, of_lm3697_leds_match);
+
+static struct i2c_driver lm3697_driver = {
+	.driver = {
+		.name	= "lm3697",
+		.of_match_table = of_lm3697_leds_match,
+	},
+	.probe		= lm3697_probe,
+	.remove		= lm3697_remove,
+	.id_table	= lm3697_id,
+};
+module_i2c_driver(lm3697_driver);
+
+MODULE_DESCRIPTION("Texas Instruments LM3697 LED driver");
+MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
+MODULE_LICENSE("GPL v2");
-- 
2.17.0.582.gccdcbd54c

Re: [PATCH v3 1/2] dt-bindings: leds: Add bindings for lm3697 driver

[Jacek Anaszewski]

Hi Dan,

Thank you for the update.

On 08/15/2018 06:17 PM, Dan Murphy wrote:
> Add the device tree bindings for the lm3697
> LED driver for backlighting and display.
> 
> Signed-off-by: Dan Murphy <dmurphy@ti.com>
> ---
> 
> v3 - Updated subject with prefered title - https://lore.kernel.org/patchwork/patch/972337/
> v2 - Fixed subject and patch commit message - https://lore.kernel.org/patchwork/patch/971326/
> 
>  .../devicetree/bindings/leds/leds-lm3697.txt  | 89 +++++++++++++++++++
>  1 file changed, 89 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/leds/leds-lm3697.txt
> 
> diff --git a/Documentation/devicetree/bindings/leds/leds-lm3697.txt b/Documentation/devicetree/bindings/leds/leds-lm3697.txt
> new file mode 100644
> index 000000000000..34403a48a0ce
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/leds-lm3697.txt
> @@ -0,0 +1,89 @@
> +* Texas Instruments - LM3697 Highly Efficient White LED Driver
> +
> +The LM3697 11-bit LED driver provides high-
> +performance backlight dimming for 1, 2, or 3 series
> +LED strings while delivering up to 90% efficiency.
> +
> +This device is suitable for Display and Keypad Lighting
> +
> +Required properties:
> +	- compatible:
> +		"ti,lm3967"
> +	- reg :  I2C slave address
> +	- #address-cells : 1
> +	- #size-cells : 0
> +
> +Optional properties:
> +	- enable-gpios : gpio pin to enable/disable the device.
> +	- vled-supply : LED supply
> +
> +Required child properties:
> +	- reg : 0 - LED is Controlled by bank A
> +		1 - LED is Controlled by bank B
> +	- led-sources - Indicates which HVLED string is associated to which
> +			control bank.  The HVLED string cannot be associated with
> +			two control banks.  This property is an array of 3 and
> +			all positions in the array must be populated.
> +			Additional information is contained
> +			in Documentation/devicetree/bindings/leds/common.txt
> +			0 - End of array if all 3 LEDs are not declared for a
> +			    single control bank.

This is needless complication. I propose to define led-sources as
an array of three boolean values, whose state signifies which LED
strings are controlled by the bank defined by the reg property in the
given child node. I.e. <HVLED1 HVLED2 HVLED3>.

I modified your examples below accordingly.

> +			1 - HVLED 1 string
> +			2 - HVLED 2 string
> +			3 - HVLED 3 string
> +
> +Optional child properties:
> +	- label : see Documentation/devicetree/bindings/leds/common.txt
> +	- linux,default-trigger :
> +	   see Documentation/devicetree/bindings/leds/common.txt
> +
> +Example:
> +
> +HVLED string 1 and 2 controlled by control bank A and HVLED string controlled by
> +control bank B.
> +
> +led-controller@36 {
> +	compatible = "ti,lm3967";
> +	reg = <0x36>;
> +	#address-cells = <1>;
> +	#size-cells = <0>;
> +
> +	enable-gpios = <&gpio1 28 GPIO_ACTIVE_HIGH>;
> +	vled-supply = <&vbatt>;
> +
> +	led@0 {
> +		reg = <0>;
> +		led-sources = <0x1 0x2 0x0>

		led-sources = <1 1 0>;
;
> +		label = "white:first_backlight_cluster";
> +		linux,default-trigger = "backlight";
> +	};
> +
> +	led@1 {
> +		reg = <1>;
> +		led-sources = <0x3 0x0 0x0>;

		led-sources = <0 0 1>;

> +		label = "white:second_backlight_cluster";
> +		linux,default-trigger = "backlight";
> +	};
> +}
> +
> +All HVLED strings controlled by control bank A
> +
> +led-controller@36 {
> +	compatible = "ti,lm3967";
> +	reg = <0x36>;
> +	#address-cells = <1>;
> +	#size-cells = <0>;
> +
> +	enable-gpios = <&gpio1 28 GPIO_ACTIVE_HIGH>;
> +	vled-supply = <&vbatt>;
> +
> +	led@0 {
> +		reg = <0>;
> +		led-sources = <0x1 0x2 0x3>;

		led-sources = <1 1 1>;

> +		label = "white:backlight_cluster";
> +		linux,default-trigger = "backlight";
> +	};
> +}
> +
> +For more product information please see the link below:
> +http://www.ti.com/lit/ds/symlink/lm3697.pdf
> 

-- 
Best regards,
Jacek Anaszewski

Re: [PATCH v3 1/2] dt-bindings: leds: Add bindings for lm3697 driver

[Dan Murphy]

Jacek

On 08/15/2018 11:56 AM, Jacek Anaszewski wrote:
> Hi Dan,
> 
> Thank you for the update.
> 
> On 08/15/2018 06:17 PM, Dan Murphy wrote:
>> Add the device tree bindings for the lm3697
>> LED driver for backlighting and display.
>>
>> Signed-off-by: Dan Murphy <dmurphy@ti.com>
>> ---
>>
>> v3 - Updated subject with prefered title - https://lore.kernel.org/patchwork/patch/972337/
>> v2 - Fixed subject and patch commit message - https://lore.kernel.org/patchwork/patch/971326/
>>
>>  .../devicetree/bindings/leds/leds-lm3697.txt  | 89 +++++++++++++++++++
>>  1 file changed, 89 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/leds/leds-lm3697.txt
>>
>> diff --git a/Documentation/devicetree/bindings/leds/leds-lm3697.txt b/Documentation/devicetree/bindings/leds/leds-lm3697.txt
>> new file mode 100644
>> index 000000000000..34403a48a0ce
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/leds/leds-lm3697.txt
>> @@ -0,0 +1,89 @@
>> +* Texas Instruments - LM3697 Highly Efficient White LED Driver
>> +
>> +The LM3697 11-bit LED driver provides high-
>> +performance backlight dimming for 1, 2, or 3 series
>> +LED strings while delivering up to 90% efficiency.
>> +
>> +This device is suitable for Display and Keypad Lighting
>> +
>> +Required properties:
>> +	- compatible:
>> +		"ti,lm3967"
>> +	- reg :  I2C slave address
>> +	- #address-cells : 1
>> +	- #size-cells : 0
>> +
>> +Optional properties:
>> +	- enable-gpios : gpio pin to enable/disable the device.
>> +	- vled-supply : LED supply
>> +
>> +Required child properties:
>> +	- reg : 0 - LED is Controlled by bank A
>> +		1 - LED is Controlled by bank B
>> +	- led-sources - Indicates which HVLED string is associated to which
>> +			control bank.  The HVLED string cannot be associated with
>> +			two control banks.  This property is an array of 3 and
>> +			all positions in the array must be populated.
>> +			Additional information is contained
>> +			in Documentation/devicetree/bindings/leds/common.txt
>> +			0 - End of array if all 3 LEDs are not declared for a
>> +			    single control bank.
> 
> This is needless complication. I propose to define led-sources as
> an array of three boolean values, whose state signifies which LED
> strings are controlled by the bank defined by the reg property in the
> given child node. I.e. <HVLED1 HVLED2 HVLED3>.

I struggled a bit with this definition.  Once I got it working it ended up producing
an overly complex control bank algorithm.

I will take a look at implementing the suggestion but the complication comes in the
numerous DT configurations we could encounter.  Part of the issue is that the user
can connect to CTRL bank b only or CTRL bank a only or a combination of that

2^3

Dan

> 
> I modified your examples below accordingly.
> 
>> +			1 - HVLED 1 string
>> +			2 - HVLED 2 string
>> +			3 - HVLED 3 string
>> +
>> +Optional child properties:
>> +	- label : see Documentation/devicetree/bindings/leds/common.txt
>> +	- linux,default-trigger :
>> +	   see Documentation/devicetree/bindings/leds/common.txt
>> +
>> +Example:
>> +
>> +HVLED string 1 and 2 controlled by control bank A and HVLED string controlled by
>> +control bank B.
>> +
>> +led-controller@36 {
>> +	compatible = "ti,lm3967";
>> +	reg = <0x36>;
>> +	#address-cells = <1>;
>> +	#size-cells = <0>;
>> +
>> +	enable-gpios = <&gpio1 28 GPIO_ACTIVE_HIGH>;
>> +	vled-supply = <&vbatt>;
>> +
>> +	led@0 {
>> +		reg = <0>;
>> +		led-sources = <0x1 0x2 0x0>
> 
> 		led-sources = <1 1 0>;
> ;
>> +		label = "white:first_backlight_cluster";
>> +		linux,default-trigger = "backlight";
>> +	};
>> +
>> +	led@1 {
>> +		reg = <1>;
>> +		led-sources = <0x3 0x0 0x0>;
> 
> 		led-sources = <0 0 1>;
> 
>> +		label = "white:second_backlight_cluster";
>> +		linux,default-trigger = "backlight";
>> +	};
>> +}
>> +
>> +All HVLED strings controlled by control bank A
>> +
>> +led-controller@36 {
>> +	compatible = "ti,lm3967";
>> +	reg = <0x36>;
>> +	#address-cells = <1>;
>> +	#size-cells = <0>;
>> +
>> +	enable-gpios = <&gpio1 28 GPIO_ACTIVE_HIGH>;
>> +	vled-supply = <&vbatt>;
>> +
>> +	led@0 {
>> +		reg = <0>;
>> +		led-sources = <0x1 0x2 0x3>;
> 
> 		led-sources = <1 1 1>;
> 
>> +		label = "white:backlight_cluster";
>> +		linux,default-trigger = "backlight";
>> +	};
>> +}
>> +
>> +For more product information please see the link below:
>> +http://www.ti.com/lit/ds/symlink/lm3697.pdf
>>
> 


-- 
------------------
Dan Murphy

Re: [PATCH v3 1/2] dt-bindings: leds: Add bindings for lm3697 driver

[Jacek Anaszewski]

Dan,

On 08/15/2018 07:30 PM, Dan Murphy wrote:
> Jacek
> 
> On 08/15/2018 11:56 AM, Jacek Anaszewski wrote:
>> Hi Dan,
>>
>> Thank you for the update.
>>
>> On 08/15/2018 06:17 PM, Dan Murphy wrote:
>>> Add the device tree bindings for the lm3697
>>> LED driver for backlighting and display.
>>>
>>> Signed-off-by: Dan Murphy <dmurphy@ti.com>
>>> ---
>>>
>>> v3 - Updated subject with prefered title - https://lore.kernel.org/patchwork/patch/972337/
>>> v2 - Fixed subject and patch commit message - https://lore.kernel.org/patchwork/patch/971326/
>>>
>>>  .../devicetree/bindings/leds/leds-lm3697.txt  | 89 +++++++++++++++++++
>>>  1 file changed, 89 insertions(+)
>>>  create mode 100644 Documentation/devicetree/bindings/leds/leds-lm3697.txt
>>>
>>> diff --git a/Documentation/devicetree/bindings/leds/leds-lm3697.txt b/Documentation/devicetree/bindings/leds/leds-lm3697.txt
>>> new file mode 100644
>>> index 000000000000..34403a48a0ce
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/leds/leds-lm3697.txt
>>> @@ -0,0 +1,89 @@
>>> +* Texas Instruments - LM3697 Highly Efficient White LED Driver
>>> +
>>> +The LM3697 11-bit LED driver provides high-
>>> +performance backlight dimming for 1, 2, or 3 series
>>> +LED strings while delivering up to 90% efficiency.
>>> +
>>> +This device is suitable for Display and Keypad Lighting
>>> +
>>> +Required properties:
>>> +	- compatible:
>>> +		"ti,lm3967"
>>> +	- reg :  I2C slave address
>>> +	- #address-cells : 1
>>> +	- #size-cells : 0
>>> +
>>> +Optional properties:
>>> +	- enable-gpios : gpio pin to enable/disable the device.
>>> +	- vled-supply : LED supply
>>> +
>>> +Required child properties:
>>> +	- reg : 0 - LED is Controlled by bank A
>>> +		1 - LED is Controlled by bank B
>>> +	- led-sources - Indicates which HVLED string is associated to which
>>> +			control bank.  The HVLED string cannot be associated with
>>> +			two control banks.  This property is an array of 3 and
>>> +			all positions in the array must be populated.
>>> +			Additional information is contained
>>> +			in Documentation/devicetree/bindings/leds/common.txt
>>> +			0 - End of array if all 3 LEDs are not declared for a
>>> +			    single control bank.
>>
>> This is needless complication. I propose to define led-sources as
>> an array of three boolean values, whose state signifies which LED
>> strings are controlled by the bank defined by the reg property in the
>> given child node. I.e. <HVLED1 HVLED2 HVLED3>.
> 
> I struggled a bit with this definition.  Once I got it working it ended up producing
> an overly complex control bank algorithm.
> 
> I will take a look at implementing the suggestion but the complication comes in the
> numerous DT configurations we could encounter.  Part of the issue is that the user
> can connect to CTRL bank b only or CTRL bank a only or a combination of that
> 
> 2^3

I tried to play a bit with that and here is what I got (simplified
DT parsing):

int used_hvleds[3] = {0, 0 ,0};
int used_control_banks[2] = {0, 0};

int parse_child_node(struct fwnode_handle *child)
{
	int bank_hvleds[3];

	fwnode_property_read_u32_array(child, "led-sources",
		bank_hvleds, LM3697_MAX_LED_STRINGS);

	for (i = 0; i <= 3; i++) {
		if (bank_hvleds[i] && used_hvleds[i])
			return -EINVAL;
		used_hvleds[i] = 1;
	}

	return 0;
}

struct fwnode_handle *child = NULL;

device_for_each_child_node(priv->dev, child)
	fwnode_property_read_u32(child, "reg", &control_bank);
	if (used_control_banks[control_bank])
		goto err;
	used_control_banks[control_bank] = 1;
	if (parse_child_node(child))
		goto err;


>>
>> I modified your examples below accordingly.
>>
>>> +			1 - HVLED 1 string
>>> +			2 - HVLED 2 string
>>> +			3 - HVLED 3 string
>>> +
>>> +Optional child properties:
>>> +	- label : see Documentation/devicetree/bindings/leds/common.txt
>>> +	- linux,default-trigger :
>>> +	   see Documentation/devicetree/bindings/leds/common.txt
>>> +
>>> +Example:
>>> +
>>> +HVLED string 1 and 2 controlled by control bank A and HVLED string controlled by
>>> +control bank B.
>>> +
>>> +led-controller@36 {
>>> +	compatible = "ti,lm3967";
>>> +	reg = <0x36>;
>>> +	#address-cells = <1>;
>>> +	#size-cells = <0>;
>>> +
>>> +	enable-gpios = <&gpio1 28 GPIO_ACTIVE_HIGH>;
>>> +	vled-supply = <&vbatt>;
>>> +
>>> +	led@0 {
>>> +		reg = <0>;
>>> +		led-sources = <0x1 0x2 0x0>
>>
>> 		led-sources = <1 1 0>;
>> ;
>>> +		label = "white:first_backlight_cluster";
>>> +		linux,default-trigger = "backlight";
>>> +	};
>>> +
>>> +	led@1 {
>>> +		reg = <1>;
>>> +		led-sources = <0x3 0x0 0x0>;
>>
>> 		led-sources = <0 0 1>;
>>
>>> +		label = "white:second_backlight_cluster";
>>> +		linux,default-trigger = "backlight";
>>> +	};
>>> +}
>>> +
>>> +All HVLED strings controlled by control bank A
>>> +
>>> +led-controller@36 {
>>> +	compatible = "ti,lm3967";
>>> +	reg = <0x36>;
>>> +	#address-cells = <1>;
>>> +	#size-cells = <0>;
>>> +
>>> +	enable-gpios = <&gpio1 28 GPIO_ACTIVE_HIGH>;
>>> +	vled-supply = <&vbatt>;
>>> +
>>> +	led@0 {
>>> +		reg = <0>;
>>> +		led-sources = <0x1 0x2 0x3>;
>>
>> 		led-sources = <1 1 1>;
>>
>>> +		label = "white:backlight_cluster";
>>> +		linux,default-trigger = "backlight";
>>> +	};
>>> +}
>>> +
>>> +For more product information please see the link below:
>>> +http://www.ti.com/lit/ds/symlink/lm3697.pdf
>>>
>>
> 
> 

-- 
Best regards,
Jacek Anaszewski

Re: [PATCH v3 1/2] dt-bindings: leds: Add bindings for lm3697 driver

[Dan Murphy]

Jacek

On 08/15/2018 01:09 PM, Jacek Anaszewski wrote:
> Dan,
> 
> On 08/15/2018 07:30 PM, Dan Murphy wrote:
>> Jacek
>>
>> On 08/15/2018 11:56 AM, Jacek Anaszewski wrote:
>>> Hi Dan,
>>>
>>> Thank you for the update.
>>>
>>> On 08/15/2018 06:17 PM, Dan Murphy wrote:
>>>> Add the device tree bindings for the lm3697
>>>> LED driver for backlighting and display.
>>>>
>>>> Signed-off-by: Dan Murphy <dmurphy@ti.com>
>>>> ---
>>>>
>>>> v3 - Updated subject with prefered title - https://lore.kernel.org/patchwork/patch/972337/
>>>> v2 - Fixed subject and patch commit message - https://lore.kernel.org/patchwork/patch/971326/
>>>>
>>>>  .../devicetree/bindings/leds/leds-lm3697.txt  | 89 +++++++++++++++++++
>>>>  1 file changed, 89 insertions(+)
>>>>  create mode 100644 Documentation/devicetree/bindings/leds/leds-lm3697.txt
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/leds/leds-lm3697.txt b/Documentation/devicetree/bindings/leds/leds-lm3697.txt
>>>> new file mode 100644
>>>> index 000000000000..34403a48a0ce
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/leds/leds-lm3697.txt
>>>> @@ -0,0 +1,89 @@
>>>> +* Texas Instruments - LM3697 Highly Efficient White LED Driver
>>>> +
>>>> +The LM3697 11-bit LED driver provides high-
>>>> +performance backlight dimming for 1, 2, or 3 series
>>>> +LED strings while delivering up to 90% efficiency.
>>>> +
>>>> +This device is suitable for Display and Keypad Lighting
>>>> +
>>>> +Required properties:
>>>> +	- compatible:
>>>> +		"ti,lm3967"
>>>> +	- reg :  I2C slave address
>>>> +	- #address-cells : 1
>>>> +	- #size-cells : 0
>>>> +
>>>> +Optional properties:
>>>> +	- enable-gpios : gpio pin to enable/disable the device.
>>>> +	- vled-supply : LED supply
>>>> +
>>>> +Required child properties:
>>>> +	- reg : 0 - LED is Controlled by bank A
>>>> +		1 - LED is Controlled by bank B
>>>> +	- led-sources - Indicates which HVLED string is associated to which
>>>> +			control bank.  The HVLED string cannot be associated with
>>>> +			two control banks.  This property is an array of 3 and
>>>> +			all positions in the array must be populated.
>>>> +			Additional information is contained
>>>> +			in Documentation/devicetree/bindings/leds/common.txt
>>>> +			0 - End of array if all 3 LEDs are not declared for a
>>>> +			    single control bank.
>>>
>>> This is needless complication. I propose to define led-sources as
>>> an array of three boolean values, whose state signifies which LED
>>> strings are controlled by the bank defined by the reg property in the
>>> given child node. I.e. <HVLED1 HVLED2 HVLED3>.
>>
>> I struggled a bit with this definition.  Once I got it working it ended up producing
>> an overly complex control bank algorithm.
>>
>> I will take a look at implementing the suggestion but the complication comes in the
>> numerous DT configurations we could encounter.  Part of the issue is that the user
>> can connect to CTRL bank b only or CTRL bank a only or a combination of that
>>
>> 2^3
> 
> I tried to play a bit with that and here is what I got (simplified
> DT parsing):
> 

Thanks for the attempt.  I think with my current code patch I might be able to get this to work.
As per your suggestion.  It just takes a while to test all the combos
Dan

> int used_hvleds[3] = {0, 0 ,0};
> int used_control_banks[2] = {0, 0};
> 
> int parse_child_node(struct fwnode_handle *child)
> {
> 	int bank_hvleds[3];
> 
> 	fwnode_property_read_u32_array(child, "led-sources",
> 		bank_hvleds, LM3697_MAX_LED_STRINGS);
> 
> 	for (i = 0; i <= 3; i++) {
> 		if (bank_hvleds[i] && used_hvleds[i])
> 			return -EINVAL;
> 		used_hvleds[i] = 1;
> 	}
> 
> 	return 0;
> }
> 
> struct fwnode_handle *child = NULL;
> 
> device_for_each_child_node(priv->dev, child)
> 	fwnode_property_read_u32(child, "reg", &control_bank);
> 	if (used_control_banks[control_bank])
> 		goto err;
> 	used_control_banks[control_bank] = 1;
> 	if (parse_child_node(child))
> 		goto err;
> 
> 
>>>
>>> I modified your examples below accordingly.
>>>
>>>> +			1 - HVLED 1 string
>>>> +			2 - HVLED 2 string
>>>> +			3 - HVLED 3 string
>>>> +
>>>> +Optional child properties:
>>>> +	- label : see Documentation/devicetree/bindings/leds/common.txt
>>>> +	- linux,default-trigger :
>>>> +	   see Documentation/devicetree/bindings/leds/common.txt
>>>> +
>>>> +Example:
>>>> +
>>>> +HVLED string 1 and 2 controlled by control bank A and HVLED string controlled by
>>>> +control bank B.
>>>> +
>>>> +led-controller@36 {
>>>> +	compatible = "ti,lm3967";
>>>> +	reg = <0x36>;
>>>> +	#address-cells = <1>;
>>>> +	#size-cells = <0>;
>>>> +
>>>> +	enable-gpios = <&gpio1 28 GPIO_ACTIVE_HIGH>;
>>>> +	vled-supply = <&vbatt>;
>>>> +
>>>> +	led@0 {
>>>> +		reg = <0>;
>>>> +		led-sources = <0x1 0x2 0x0>
>>>
>>> 		led-sources = <1 1 0>;
>>> ;
>>>> +		label = "white:first_backlight_cluster";
>>>> +		linux,default-trigger = "backlight";
>>>> +	};
>>>> +
>>>> +	led@1 {
>>>> +		reg = <1>;
>>>> +		led-sources = <0x3 0x0 0x0>;
>>>
>>> 		led-sources = <0 0 1>;
>>>
>>>> +		label = "white:second_backlight_cluster";
>>>> +		linux,default-trigger = "backlight";
>>>> +	};
>>>> +}
>>>> +
>>>> +All HVLED strings controlled by control bank A
>>>> +
>>>> +led-controller@36 {
>>>> +	compatible = "ti,lm3967";
>>>> +	reg = <0x36>;
>>>> +	#address-cells = <1>;
>>>> +	#size-cells = <0>;
>>>> +
>>>> +	enable-gpios = <&gpio1 28 GPIO_ACTIVE_HIGH>;
>>>> +	vled-supply = <&vbatt>;
>>>> +
>>>> +	led@0 {
>>>> +		reg = <0>;
>>>> +		led-sources = <0x1 0x2 0x3>;
>>>
>>> 		led-sources = <1 1 1>;
>>>
>>>> +		label = "white:backlight_cluster";
>>>> +		linux,default-trigger = "backlight";
>>>> +	};
>>>> +}
>>>> +
>>>> +For more product information please see the link below:
>>>> +http://www.ti.com/lit/ds/symlink/lm3697.pdf
>>>>
>>>
>>
>>
> 


-- 
------------------
Dan Murphy