dm: treewide: Use uclass_first_device_err when accessing one device

There is a number of users that use uclass_first_device to access the
first and (assumed) only device in uclass.

Some check the return value of uclass_first_device and also that a
device was returned which is exactly what uclass_first_device_err does.

Some are not checking that a device was returned and can potentially
crash if no device exists in the uclass. Finally there is one that
returns NULL on error either way.

Convert all of these to use uclass_first_device_err instead, the return
value will be removed from uclass_first_device in a later patch.

Signed-off-by: Michal Suchanek <[email protected]>
Reviewed-by: Simon Glass <[email protected]>

4 files changed, 7 insertions, 15 deletions

diff --git a/drivers/video/exynos/exynos_fb.c b/drivers/video/exynos/exynos_fb.c
index 69992b3c2ba..86970a6d5d2 100644
--- a/drivers/video/exynos/exynos_fb.c
+++ b/drivers/video/exynos/exynos_fb.c
@@ -640,25 +640,17 @@ static int exynos_fb_probe(struct udevice *dev)
 #endif
 	exynos_fimd_lcd_init(dev);
 
-	ret = uclass_first_device(UCLASS_PANEL, &panel);
+	ret = uclass_first_device_err(UCLASS_PANEL, &panel);
 	if (ret) {
-		printf("LCD panel failed to probe\n");
+		printf("%s: LCD panel failed to probe %d\n", __func__, ret);
 		return ret;
 	}
-	if (!panel) {
-		printf("LCD panel not found\n");
-		return -ENODEV;
-	}
 
-	ret = uclass_first_device(UCLASS_DISPLAY, &dp);
+	ret = uclass_first_device_err(UCLASS_DISPLAY, &dp);
 	if (ret) {
 		debug("%s: Display device error %d\n", __func__, ret);
 		return ret;
 	}
-	if (!dev) {
-		debug("%s: Display device missing\n", __func__);
-		return -ENODEV;
-	}
 	ret = display_enable(dp, 18, NULL);
 	if (ret) {
 		debug("%s: Display enable error %d\n", __func__, ret);
diff --git a/drivers/video/mali_dp.c b/drivers/video/mali_dp.c
index ba1ddd64e08..cbcdb99e1f0 100644
--- a/drivers/video/mali_dp.c
+++ b/drivers/video/mali_dp.c
@@ -244,7 +244,7 @@ static int malidp_update_timings_from_edid(struct udevice *dev,
 	struct udevice *disp_dev;
 	int err;
 
-	err = uclass_first_device(UCLASS_DISPLAY, &disp_dev);
+	err = uclass_first_device_err(UCLASS_DISPLAY, &disp_dev);
 	if (err)
 		return err;
 
diff --git a/drivers/video/stm32/stm32_dsi.c b/drivers/video/stm32/stm32_dsi.c
index 5871ac7c4ff..e6347bb8da6 100644
--- a/drivers/video/stm32/stm32_dsi.c
+++ b/drivers/video/stm32/stm32_dsi.c
@@ -346,7 +346,7 @@ static int stm32_dsi_attach(struct udevice *dev)
 	struct display_timing timings;
 	int ret;
 
-	ret = uclass_first_device(UCLASS_PANEL, &priv->panel);
+	ret = uclass_first_device_err(UCLASS_PANEL, &priv->panel);
 	if (ret) {
 		dev_err(dev, "panel device error %d\n", ret);
 		return ret;
diff --git a/drivers/video/tegra124/dp.c b/drivers/video/tegra124/dp.c
index ee4f09a0c49..b27b1633bab 100644
--- a/drivers/video/tegra124/dp.c
+++ b/drivers/video/tegra124/dp.c
@@ -1494,8 +1494,8 @@ int tegra_dp_enable(struct udevice *dev, int panel_bpp,
 		return -ENOLINK;
 	}
 
-	ret = uclass_first_device(UCLASS_VIDEO_BRIDGE, &sor);
-	if (ret || !sor) {
+	ret = uclass_first_device_err(UCLASS_VIDEO_BRIDGE, &sor);
+	if (ret) {
 		debug("dp: failed to find SOR device: ret=%d\n", ret);
 		return ret;
 	}