[PATCH AUTOSEL 5.4 08/52] drm/amd/display: Fixed kernel panic when booting with DP-to-HDMI dongle

Sasha Levin sashal at kernel.org
Fri Dec 20 14:29:10 UTC 2019


From: David Galiffi <David.Galiffi at amd.com>

[ 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 at amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng at amd.com>
Acked-by: Leo Li <sunpeng.li at amd.com>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
Signed-off-by: Sasha Levin <sashal at kernel.org>
---
 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 ca20b150afcc2..6cb91a8eb2e0c 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -373,7 +373,7 @@ 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



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