linux-kernel - [PATCH] backlight: gpio_backlight: Drop output gpio direction check for initial power state

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Message-ID: <20230720061105.154821-1-victor.liu@nxp.com>
Date:   Thu, 20 Jul 2023 06:06:27 +0000
From:   Ying Liu <victor.liu@....com>
To:     "dri-devel@...ts.freedesktop.org" <dri-devel@...ts.freedesktop.org>,
        "linux-fbdev@...r.kernel.org" <linux-fbdev@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
CC:     "lee@...nel.org" <lee@...nel.org>,
        "daniel.thompson@...aro.org" <daniel.thompson@...aro.org>,
        "jingoohan1@...il.com" <jingoohan1@...il.com>,
        "deller@....de" <deller@....de>
Subject: [PATCH] backlight: gpio_backlight: Drop output gpio direction check
 for initial power state

Bootloader may leave gpio direction as input and gpio value as logical low.
It hints that initial backlight power state should be FB_BLANK_POWERDOWN
since the gpio value is literally logical low.  So, let's drop output gpio
direction check and only check gpio value to set the initial power state.

Signed-off-by: Liu Ying <victor.liu@....com>
---
 drivers/video/backlight/gpio_backlight.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c
index d3bea42407f1..d28c30b2a35d 100644
--- a/drivers/video/backlight/gpio_backlight.c
+++ b/drivers/video/backlight/gpio_backlight.c
@@ -87,8 +87,7 @@ static int gpio_backlight_probe(struct platform_device *pdev)
 		/* Not booted with device tree or no phandle link to the node */
 		bl->props.power = def_value ? FB_BLANK_UNBLANK
 					    : FB_BLANK_POWERDOWN;
-	else if (gpiod_get_direction(gbl->gpiod) == 0 &&
-		 gpiod_get_value_cansleep(gbl->gpiod) == 0)
+	else if (gpiod_get_value_cansleep(gbl->gpiod) == 0)
 		bl->props.power = FB_BLANK_POWERDOWN;
 	else
 		bl->props.power = FB_BLANK_UNBLANK;
-- 
2.37.1