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Subject[PATCH v3 2/5] dt-bindings: pwm-backlight: add PWM delay proprieties.
Date
Hardware needs a delay between setting an initial (non-zero) PWM and
enabling the backlight using GPIO. The post-pwm-on-delay-us specifies
this delay in micro seconds. Hardware also needs a delay between disabing
the backlight using GPIO and setting PWM value to 0. The pwm-off-delay-us
is this delay in micro seconds.

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
---
Based on the original Huang Lin <hl@rock-chips.com> work.

Changes since v2:
- Use separate properties (Rob Herring)
Changes since v1:
- As suggested by Daniel Thompson
- Do not assume power-on delay and power-off delay will be the same

Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt b/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt
index 764db86..810527c 100644
--- a/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt
+++ b/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt
@@ -17,6 +17,10 @@ Optional properties:
"pwms" property (see PWM binding[0])
- enable-gpios: contains a single GPIO specifier for the GPIO which enables
and disables the backlight (see GPIO binding[1])
+ - post-pwm-on-delay-us: Delay in us between setting an initial (non-zero) PWM
+ and enabling the backlight using GPIO.
+ - pwm-off-delay-us: Delay in us between disabling the backlight using GPIO
+ and setting PWM value to 0.

[0]: Documentation/devicetree/bindings/pwm/pwm.txt
[1]: Documentation/devicetree/bindings/gpio/gpio.txt
@@ -32,4 +36,6 @@ Example:

power-supply = <&vdd_bl_reg>;
enable-gpios = <&gpio 58 0>;
+ post-pwm-on-delay-us = <10000>;
+ pwm-off-delay-us = <10000>;
};
--
2.9.3
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