Add a YAML devicetree binding for the Richtek RT8515 dual channel flash/torch LED driver. Cc: Sakari Ailus <sakari.ailus@xxxxxx> Cc: newbytee@xxxxxxxxxxxxxx Cc: Stephan Gerhold <stephan@xxxxxxxxxxx> Cc: phone-devel@xxxxxxxxxxxxxxx Cc: linux-media@xxxxxxxxxxxxxxx Cc: devicetree@xxxxxxxxxxxxxxx Reviewed-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx> --- ChangeLog v6->v7: - Use led-max-microamp for the torch mode max current. - Drop the torch-specific new property from common.yaml in favor of this property. - Collect Sakari's review tag. ChangeLog v5->v6: - Use the suffix -ohms for the resistor values as this gets recognized by default by dtschema and is nominal. ChangeLog v4->v5: - Fix the RFS/RTS resistors to reference the u32 schema. - Fix resisitor speling error. ChangeLog v3->v4: - Add DT attributes for the RFS and RTS resistors, so that the hardware-defined maximum current can be determined. - Add torch-max-microamp to the common bindings so we can set an attribute for the max microamp in torch mode. - Add flash-max-microamp and torch-max-microamp as optional to the LED node. - Slot in some elabortative descriptions of the new properties and describe what the hardware is doing. - Cc phone-devel@xxxxxxxxxxxxxxx ChangeLog v2->v3: - Add Sakari to CC - Resend ChangeLog v1->v2: - Explicitly inherit function, color and flash-max-timeout-us from common.yaml - Add "led" node as required. --- .../bindings/leds/richtek,rt8515.yaml | 109 ++++++++++++++++++ 1 file changed, 109 insertions(+) create mode 100644 Documentation/devicetree/bindings/leds/richtek,rt8515.yaml diff --git a/Documentation/devicetree/bindings/leds/richtek,rt8515.yaml b/Documentation/devicetree/bindings/leds/richtek,rt8515.yaml new file mode 100644 index 000000000000..3190e4fcfdf2 --- /dev/null +++ b/Documentation/devicetree/bindings/leds/richtek,rt8515.yaml @@ -0,0 +1,109 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/leds/richtek,rt8515.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Richtek RT8515 1.5A dual channel LED driver + +maintainers: + - Linus Walleij <linus.walleij@xxxxxxxxxx> + +description: | + The Richtek RT8515 is a dual channel (two mode) LED driver that + supports driving a white LED in flash or torch mode. The maximum + current for each mode is defined in hardware using two resistors + RFS and RTS. + +properties: + compatible: + const: richtek,rt8515 + + enf-gpios: + maxItems: 1 + description: A connection to the 'ENF' (enable flash) pin. + + ent-gpios: + maxItems: 1 + description: A connection to the 'ENT' (enable torch) pin. + + richtek,rfs-ohms: + minimum: 7680 + maximum: 367000 + description: The resistance value of the RFS resistor. This + resistors limits the maximum flash current. This must be set + for the property flash-max-microamp to work, the RFS resistor + defines the range of the dimmer setting (brightness) of the + flash LED. + + richtek,rts-ohms: + minimum: 7680 + maximum: 367000 + description: The resistance value of the RTS resistor. This + resistors limits the maximum torch current. This must be set + for the property torch-max-microamp to work, the RTS resistor + defines the range of the dimmer setting (brightness) of the + torch LED. + + led: + type: object + $ref: common.yaml# + properties: + function: true + color: true + flash-max-timeout-us: true + + flash-max-microamp: + maximum: 700000 + description: The maximum current for flash mode + is hardwired to the component using the RFS resistor to + ground. The maximum hardware current setting is calculated + according to the formula Imax = 5500 / RFS. The lowest + allowed resistance value is 7.86 kOhm giving an absolute + maximum current of 700mA. By setting this attribute in + the device tree, you can further restrict the maximum + current below the hardware limit. This requires the RFS + to be defined as it defines the maximum range. + + led-max-microamp: + maximum: 700000 + description: The maximum current for torch mode + is hardwired to the component using the RTS resistor to + ground. The maximum hardware current setting is calculated + according to the formula Imax = 5500 / RTS. The lowest + allowed resistance value is 7.86 kOhm giving an absolute + maximum current of 700mA. By setting this attribute in + the device tree, you can further restrict the maximum + current below the hardware limit. This requires the RTS + to be defined as it defines the maximum range. + +required: + - compatible + - ent-gpios + - enf-gpios + - led + +additionalProperties: false + +examples: + - | + #include <dt-bindings/gpio/gpio.h> + #include <dt-bindings/leds/common.h> + + led-controller { + compatible = "richtek,rt8515"; + enf-gpios = <&gpio4 12 GPIO_ACTIVE_HIGH>; + ent-gpios = <&gpio4 13 GPIO_ACTIVE_HIGH>; + richtek,rfs-ohms = <16000>; + richtek,rts-ohms = <100000>; + + led { + function = LED_FUNCTION_FLASH; + color = <LED_COLOR_ID_WHITE>; + flash-max-timeout-us = <250000>; + flash-max-microamp = <150000>; + torch-max-microamp = <25000>; + }; + }; + +... -- 2.26.2
