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Re: [PATCH 2/2] backlight: pwm_bl: Check the pwm state for initial backlight power state

From Lee Jones <lee.jones@linaro.org>
Newsgroups linux.kernel
Subject Re: [PATCH 2/2] backlight: pwm_bl: Check the pwm state for initial backlight power state
Date 2016-10-26 14:20 +0200
Message-ID <swvlw-3vY-13@gated-at.bofh.it> (permalink)
References <sn07f-73F-7@gated-at.bofh.it> <sn07f-73F-5@gated-at.bofh.it>
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On Fri, 30 Sep 2016, Peter Ujfalusi wrote:

> If the pwm is not enabled the backlight initially should not be enabled
> either if we have booted with DT and there is a phandle pointing to the
> backlight node.
> 
> The patch extends the checks to decide if we should keep the backlight off
> initially.
> 
> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
> ---
>  drivers/video/backlight/pwm_bl.c | 4 ++++
>  1 file changed, 4 insertions(+)

Makes sense to me.

I'm going to apply this until someone screams at me.

> diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c
> index 9bc4715bf116..e4326bbf807f 100644
> --- a/drivers/video/backlight/pwm_bl.c
> +++ b/drivers/video/backlight/pwm_bl.c
> @@ -223,6 +223,10 @@ static int pwm_backlight_initial_power_state(const struct pwm_bl_data *pb)
>  	if (!regulator_is_enabled(pb->power_supply))
>  		return FB_BLANK_POWERDOWN;
>  
> +	/* The pwm is disabled, keep it like this */
> +	if (!pwm_is_enabled(pb->pwm))
> +		return FB_BLANK_POWERDOWN;
> +
>  	return FB_BLANK_UNBLANK;
>  }
>  

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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Re: [PATCH 2/2] backlight: pwm_bl: Check the pwm state for initial  backlight power state Lee Jones <lee.jones@linaro.org> - 2016-10-26 14:20 +0200

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