[PATCH 2/2] gpu/drm: ingenic: Add workaround for disabled drivers

From: Paul Cercueil
Date: Thu Aug 05 2021 - 15:21:36 EST


When the drivers of remote devices (e.g. HDMI chip) are disabled in the
config, we want the ingenic-drm driver to be able to probe nonetheless
with the other devices (e.g. internal LCD panel) that are enabled.

Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
---
drivers/gpu/drm/ingenic/ingenic-drm-drv.c | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c
index d261f7a03b18..5e1fdbb0ba6b 100644
--- a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c
+++ b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c
@@ -1058,6 +1058,18 @@ static int ingenic_drm_bind(struct device *dev, bool has_components)
for (i = 0; ; i++) {
ret = drm_of_find_panel_or_bridge(dev->of_node, 0, i, &panel, &bridge);
if (ret) {
+ /*
+ * Workaround for the case where the drivers for the
+ * remote devices are not enabled. When that happens,
+ * drm_of_find_panel_or_bridge() returns -EPROBE_DEFER
+ * endlessly, which prevents the ingenic-drm driver from
+ * working at all.
+ */
+ if (ret == -EPROBE_DEFER) {
+ ret = driver_deferred_probe_check_state(dev);
+ if (ret == -ENODEV || ret == -ETIMEDOUT)
+ continue;
+ }
if (ret == -ENODEV)
break; /* we're done */
if (ret != -EPROBE_DEFER)
--
2.30.2