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Message-ID: <1446133259.3274.52.camel@pengutronix.de>
Subject: Re: [PATCH v2] pwm-backlight: fix the panel power sequence
From: Philipp Zabel <p.zabel@pengutronix.de>
To: YH Huang <yh.huang@mediatek.com>
Cc: Thierry Reding <thierry.reding@gmail.com>,
        Jingoo Han <jingoohan1@gmail.com>, Lee Jones <lee.jones@linaro.org>,
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Date: Thu, 29 Oct 2015 16:40:59 +0100
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Hi YH,

Am Donnerstag, den 22.10.2015, 23:12 +0800 schrieb YH Huang:
> In the case of the panel disabled by the bootloader,
> your patch still has the following code and always enables the backlight
> in the probe function.
> pb->enable_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
> -						  GPIOD_OUT_HIGH);

You are right.

> What do you think if I remove these two lines in my patch?
> if (pb->enable_gpio)
> 	gpiod_direction_output(pb->enable_gpio, 0);

That won't work if the gpio is still configured as input. How about I
add the GPIOD_ASIS change to my patch you remove that and the above from
yours?

best regards
Philipp