The Monolithic Power (MPS) MP3309C is a WLED step-up converter, featuring a programmable switching frequency to optimize efficiency. The brightness can be controlled either by I2C commands (called "analog" mode) or by a PWM input signal (PWM mode). This driver supports both modes. For device driver details, please refer to: - drivers/video/backlight/mp3309c_bl.c The datasheet is available at: - https://www.monolithicpower.com/en/mp3309c.html Signed-off-by: Flavio Suligoi <f.suligoi@xxxxxxx> --- .../bindings/leds/backlight/mps,mp3309c.yaml | 202 ++++++++++++++++++ 1 file changed, 202 insertions(+) create mode 100644 Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml diff --git a/Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml b/Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml new file mode 100644 index 000000000000..a58904f2a271 --- /dev/null +++ b/Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml @@ -0,0 +1,202 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/leds/backlight/mps,mp3309c.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: MPS MP3309C backlight + +maintainers: + - Flavio Suligoi <f.suligoi@xxxxxxx> + +description: | + The Monolithic Power (MPS) MP3309C is a WLED step-up converter, featuring a + programmable switching frequency to optimize efficiency. + It supports both analog (via I2C commands) and PWM dimming mode. + + The datasheet is available at: + https://www.monolithicpower.com/en/mp3309c.html + +properties: + compatible: + const: mps,mp3309c-backlight + + reg: + maxItems: 1 + + mps,dimming-mode: + description: The dimming mode (PWM or analog by I2C commands). + $ref: '/schemas/types.yaml#/definitions/string' + enum: + - pwm + - analog-i2c + + pinctrl-names: + items: + - const: default + + pinctrl-0: true + + pwms: + description: PWM channel used for controlling the backlight in "pwm" dimming + mode. + maxItems: 1 + + default-brightness: + minimum: 0 + + max-brightness: + minimum: 1 + + enable-gpios: + description: GPIO used to enable the backlight in "analog-i2c" dimming mode. + maxItems: 1 + + mps,switch-on-delay-ms: + description: delay (in ms) before switch on the backlight, to wait for image + stabilization. + default: 10 + + mps,switch-off-delay-ms: + description: delay (in ms) after the switch off command to the backlight. + default: 0 + + mps,overvoltage-protection-13v: + description: overvoltage protection set to 13.5V. + type: boolean + mps,overvoltage-protection-24v: + description: overvoltage protection set to 24V. + type: boolean + mps,overvoltage-protection-35v: + description: overvoltage protection set to 35.5V. + type: boolean + + mps,reset-gpios: + description: optional GPIO to reset an external device (LCD panel, FPGA, + etc.) when the backlight is switched on. + maxItems: 1 + + mps,reset-on-delay-ms: + description: delay (in s) before generating the reset-gpios. + default: 10 + + mps,reset-on-length-ms: + description: pulse length (in ms) for reset-gpios. + default: 10 + +oneOf: + - required: + - mps,overvoltage-protection-13v + - required: + - mps,overvoltage-protection-24v + - required: + - mps,overvoltage-protection-35.5v + +allOf: + - $ref: common.yaml# + - if: + properties: + mps,dimming-mode: + contains: + enum: + - pwm + then: + required: + - pwms + not: + required: + - enable-gpios + + - if: + properties: + mps,dimming-mode: + contains: + enum: + - analog-i2c + then: + required: + - enable-gpios + not: + required: + - pwms + +required: + - compatible + - reg + - mps,dimming-mode + - max-brightness + - default-brightness + +additionalProperties: false + +examples: + - | + #include <dt-bindings/gpio/gpio.h> + i2c3 { + #address-cells = <1>; + #size-cells = <0>; + + clock-frequency = <100000>; + pinctrl-names = "default"; + pinctrl-0 = <&pinctrl_i2c3>; + status = "okay"; + + /* Backlight with PWM control */ + backlight_pwm: backlight@17 { + compatible = "mps,mp3309c-backlight"; + reg = <0x17>; + mps,dimming-mode = "pwm"; + pinctrl-names = "default"; + pinctrl-0 = <&pinctrl_fpga_reset>; + pwms = <&pwm1 0 3333333 0>; /* 300 Hz --> (1/f) * 1*10^9 */ + max-brightness = <100>; + default-brightness = <80>; + mps,switch-on-delay-ms = <800>; + mps,switch-off-delay-ms = <10>; + mps,overvoltage-protection-24v; + + /* + * Enable an FPGA reset pulse when MIPI data are stable, + * before switch on the backlight + */ + mps,reset-gpios = <&gpio4 20 GPIO_ACTIVE_HIGH>; + mps,reset-on-delay-ms = <100>; + mps,reset-on-length-ms = <10>; + }; + }; + + - | + #include <dt-bindings/gpio/gpio.h> + /* Backlight with analog control via I2C bus */ + i2c3 { + #address-cells = <1>; + #size-cells = <0>; + + clock-frequency = <100000>; + pinctrl-names = "default"; + pinctrl-0 = <&pinctrl_i2c3>; + status = "okay"; + + backlight_analog_i2c: backlight@18 { + compatible = "mps,mp3309c-backlight"; + reg = <0x17>; + mps,dimming-mode = "analog-i2c"; + pinctrl-names = "default"; + pinctrl-0 = <&pinctrl_reg_pwm_backlight_fixed>, + <&pinctrl_fpga_reset>; + enable-gpios = <&gpio5 5 GPIO_ACTIVE_HIGH>; + max-brightness = <100>; + default-brightness = <80>; + mps,switch-on-delay-ms = <800>; + mps,switch-off-delay-ms = <10>; + mps,overvoltage-protection-24v; + + /* + * Enable an FPGA reset pulse when MIPI data are stable, + * before switch on the backlight + */ + mps,reset-gpios = <&gpio4 20 GPIO_ACTIVE_HIGH>; + mps,reset-on-delay-ms = <100>; + mps,reset-on-length-ms = <10>; + }; + }; -- 2.34.1
