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[PATCH v3 2/5] dt-bindings: pwm-backlight: add PWM delay proprieties.

From Enric Balletbo i Serra <enric.balletbo@collabora.com>
Newsgroups linux.kernel
Subject [PATCH v3 2/5] dt-bindings: pwm-backlight: add PWM delay proprieties.
Date 2017-07-17 23:30 +0200
Message-ID <u4lKy-1Tb-29@gated-at.bofh.it> (permalink)
References <u4lKx-1Tb-3@gated-at.bofh.it>
Organization linux.* mail to news gateway

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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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[PATCH v3 1/5] pwm-backlight: enable/disable the PWM before/after LCD enable toggle. Enric Balletbo i Serra <enric.balletbo@collabora.com> - 2017-07-17 23:30 +0200
  [PATCH v3 3/5] pwm-backlight: add support for PWM delays proprieties. Enric Balletbo i Serra <enric.balletbo@collabora.com> - 2017-07-17 23:30 +0200
    Re: [PATCH v3 3/5] pwm-backlight: add support for PWM delays  proprieties. Daniel Thompson <daniel.thompson@linaro.org> - 2017-07-18 11:40 +0200
      Re: [PATCH v3 3/5] pwm-backlight: add support for PWM delays  proprieties. Pavel Machek <pavel@ucw.cz> - 2017-07-20 10:10 +0200
        Re: [PATCH v3 3/5] pwm-backlight: add support for PWM delays  proprieties. Daniel Thompson <daniel.thompson@linaro.org> - 2017-07-20 12:40 +0200
          Re: [PATCH v3 3/5] pwm-backlight: add support for PWM delays  proprieties. Pavel Machek <pavel@ucw.cz> - 2017-07-20 13:10 +0200
  [PATCH v3 4/5] ARM: dts: rockchip: set PWM delay backlight settings for Veyron. Enric Balletbo i Serra <enric.balletbo@collabora.com> - 2017-07-17 23:30 +0200
  [PATCH v3 2/5] dt-bindings: pwm-backlight: add PWM delay proprieties. Enric Balletbo i Serra <enric.balletbo@collabora.com> - 2017-07-17 23:30 +0200
    Re: [PATCH v3 2/5] dt-bindings: pwm-backlight: add PWM delay  proprieties. Pavel Machek <pavel@ucw.cz> - 2017-07-20 10:10 +0200
  Re: [PATCH v3 1/5] pwm-backlight: enable/disable the PWM before/after  LCD enable toggle. Daniel Thompson <daniel.thompson@linaro.org> - 2017-07-18 11:40 +0200

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