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@xxxxxx> >>> --- >>> >>> 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
