[PATCH v2] drm/bridge: anx7625: Check GPIO description to avoid crash

From: Xin Ji
Date: Thu Nov 18 2021 - 20:58:20 EST


As GPIO probe function "devm_gpiod_get_optional()" may return error
code, driver should identify GPIO desc as NULL to avoid crash.

Acked-by: Tzung-Bi Shih <tzungbi@xxxxxxxxxx>
Signed-off-by: Xin Ji <xji@xxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/bridge/analogix/anx7625.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
index 001fb39d9919..652ae814246d 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.c
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
@@ -1098,9 +1098,18 @@ static void anx7625_init_gpio(struct anx7625_data *platform)
/* Gpio for chip power enable */
platform->pdata.gpio_p_on =
devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW);
+ if (IS_ERR_OR_NULL(platform->pdata.gpio_p_on)) {
+ DRM_DEV_DEBUG_DRIVER(dev, "no enable gpio found\n");
+ platform->pdata.gpio_p_on = NULL;
+ }
+
/* Gpio for chip reset */
platform->pdata.gpio_reset =
devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
+ if (IS_ERR_OR_NULL(platform->pdata.gpio_reset)) {
+ DRM_DEV_DEBUG_DRIVER(dev, "no reset gpio found\n");
+ platform->pdata.gpio_reset = NULL;
+ }

if (platform->pdata.gpio_p_on && platform->pdata.gpio_reset) {
platform->pdata.low_power_mode = 1;
--
2.25.1