[PATCH AUTOSEL 4.19 05/34] drm/amd/display: Fixed kernel panic when booting with DP-to-HDMI dongle

From: Sasha Levin
Date: Fri Dec 20 2019 - 09:37:06 EST


From: David Galiffi <David.Galiffi@xxxxxxx>

[ Upstream commit a51d9f8fe756beac51ce26ef54195da00a260d13 ]

[Why]
In dc_link_is_dp_sink_present, if dal_ddc_open fails, then
dal_gpio_destroy_ddc is called, destroying pin_data and pin_clock. They
are created only on dc_construct, and next aux access will cause a panic.

[How]
Instead of calling dal_gpio_destroy_ddc, call dal_ddc_close.

Signed-off-by: David Galiffi <David.Galiffi@xxxxxxx>
Reviewed-by: Tony Cheng <Tony.Cheng@xxxxxxx>
Acked-by: Leo Li <sunpeng.li@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/amd/display/dc/core/dc_link.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
index 23a7ef97afdd2..33c8eda97457f 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -348,7 +348,7 @@ bool dc_link_is_dp_sink_present(struct dc_link *link)

if (GPIO_RESULT_OK != dal_ddc_open(
ddc, GPIO_MODE_INPUT, GPIO_DDC_CONFIG_TYPE_MODE_I2C)) {
- dal_gpio_destroy_ddc(&ddc);
+ dal_ddc_close(ddc);

return present;
}
--
2.20.1