[PATCH] backlight: sky81452-backlight: Check return value of devm_gpiod_get_optional() in sky81452_bl_parse_dt()

[Chen Ni <nichen@iscas.ac.cn>]

The devm_gpiod_get_optional() function may return an ERR_PTR in case of
genuine GPIO acquisition errors, not just NULL which indicates the
legitimate absence of an optional GPIO.

Add an IS_ERR() check after the call in sky81452_bl_parse_dt(). On
error, return the error code to ensure proper failure handling rather
than proceeding with invalid pointers.

Fixes: e1915eec54a6 ("backlight: sky81452: Convert to GPIO descriptors")
Signed-off-by: Chen Ni <nichen@iscas.ac.cn>
---
 drivers/video/backlight/sky81452-backlight.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/video/backlight/sky81452-backlight.c b/drivers/video/backlight/sky81452-backlight.c
index 2749231f0385..e3e5306fab84 100644
--- a/drivers/video/backlight/sky81452-backlight.c
+++ b/drivers/video/backlight/sky81452-backlight.c
@@ -202,6 +202,10 @@ static struct sky81452_bl_platform_data *sky81452_bl_parse_dt(
 	pdata->dpwm_mode = of_property_read_bool(np, "skyworks,dpwm-mode");
 	pdata->phase_shift = of_property_read_bool(np, "skyworks,phase-shift");
 	pdata->gpiod_enable = devm_gpiod_get_optional(dev, NULL, GPIOD_OUT_HIGH);
+	if (IS_ERR(pdata->gpiod_enable)) {
+		dev_err(dev, "failed to get gpio\n");
+		return ERR_CAST(pdata->gpiod_enable);
+	}
 
 	ret = of_property_count_u32_elems(np, "led-sources");
 	if (ret < 0) {
-- 
2.25.1