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

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