[PATCH] drm/rockchip: skip probed failed device

[Jian-Hong Pan]

The cdn-dp sub driver probes the device failed on PINEBOOK Pro.

kernel: cdn-dp fec00000.dp: [drm:cdn_dp_probe [rockchipdrm]] *ERROR* missing extcon or phy
kernel: cdn-dp: probe of fec00000.dp failed with error -22

Then, the device halts all of the DRM related device jobs. For example,
the operations: vop_component_ops, vop_component_ops and
rockchip_dp_component_ops cannot be bound to corresponding devices. So,
Xorg cannot find the correct DRM device.

This patch skips the probing failed devices to fix this issue.

Link: http://lists.infradead.org/pipermail/linux-rockchip/2020-September/022352.html
Signed-off-by: Jian-Hong Pan <jhp@xxxxxxxxxxxxx>
---
 drivers/gpu/drm/rockchip/rockchip_drm_drv.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
index 0f3eb392fe39..de13588602b4 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
@@ -331,6 +331,12 @@ static struct component_match *rockchip_drm_match_add(struct device *dev)
 
 			if (!d)
 				break;
+			if (!d->driver) {
+				DRM_DEV_ERROR(d,
+					      "%s did not probe successfully",
+					      drv->driver.name);
+				continue;
+			}
 
 			device_link_add(dev, d, DL_FLAG_STATELESS);
 			component_match_add(dev, &match, compare_dev, d);
-- 
2.28.0