diff mbox series

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

Message ID 20180815161734.18159-1-dmurphy@ti.com
State New
Headers show
Series [v3,1/2] dt-bindings: leds: Add bindings for lm3697 driver | expand

Commit Message

Dan Murphy Aug. 15, 2018, 4:17 p.m. UTC 
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

-- 
2.17.0.582.gccdcbd54c

Comments

Jacek Anaszewski Aug. 15, 2018, 4:56 p.m. UTC | #1 
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
Jacek Anaszewski Aug. 15, 2018, 6:09 p.m. UTC | #2 
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
diff mbox series

Patch

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