Il 28/10/21 09:43, AngeloGioacchino Del Regno ha scritto:
In commit 41ca9caaae0b ("drm/mediatek: hdmi: Add check for CEA modes only")
a check for CEA modes was added to function mtk_hdmi_bridge_mode_valid()
in order to address possible issues on MT8167; moreover, with commit
c91026a938c2 ("drm/mediatek: hdmi: Add optional limit on maximal HDMI mode clock")
another similar check was introduced.
Unfortunately though, at the time of writing, MT8173 does not provide
any mtk_hdmi_conf structure and this is crashing the kernel with NULL
pointer upon entering mtk_hdmi_bridge_mode_valid(), which happens as
soon as a HDMI cable gets plugged in.
To fix this regression, add a NULL pointer check for hdmi->conf in the
said function, restoring HDMI functionality and avoiding NULL pointer
kernel panics.
Fixes: 41ca9caaae0b ("drm/mediatek: hdmi: Add check for CEA modes only")
Fixes: c91026a938c2 ("drm/mediatek: hdmi: Add optional limit on maximal HDMI mode clock")
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
---
drivers/gpu/drm/mediatek/mtk_hdmi.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi.c b/drivers/gpu/drm/mediatek/mtk_hdmi.c
index 5838c44cbf6f..3196189429bc 100644
--- a/drivers/gpu/drm/mediatek/mtk_hdmi.c
+++ b/drivers/gpu/drm/mediatek/mtk_hdmi.c
@@ -1224,12 +1224,14 @@ static int mtk_hdmi_bridge_mode_valid(struct drm_bridge *bridge,
return MODE_BAD;
}
- if (hdmi->conf->cea_modes_only && !drm_match_cea_mode(mode))
- return MODE_BAD;
+ if (hdmi->conf) {
+ if (hdmi->conf->cea_modes_only && !drm_match_cea_mode(mode))
+ return MODE_BAD;
- if (hdmi->conf->max_mode_clock &&
- mode->clock > hdmi->conf->max_mode_clock)
- return MODE_CLOCK_HIGH;
+ if (hdmi->conf->max_mode_clock &&
+ mode->clock > hdmi->conf->max_mode_clock)
+ return MODE_CLOCK_HIGH;
+ }
if (mode->clock < 27000)
return MODE_CLOCK_LOW;
Hello, friendly ping!
Can I please get a review (or merge) of this commit?
This is an important fix for a null pointer KP and restores HDMI functionality.
Thanks,
- Angelo