From: Kuogee Hsieh <khsieh@codeaurora.org> stable inclusion from stable-5.10.67 commit f86bc4a1a401d3691bad41e67f9db0c2ea94da32 bugzilla: 182619 https://gitee.com/openeuler/kernel/issues/I4EWO7 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 7948fe12d47a946fb8025a0534c900e3dd4b5839 ] Response with correct edid checksum saved at connector after corrupted edid checksum read. This fixes Link Layer CTS cases 4.2.2.3, 4.2.2.6. Signed-off-by: Kuogee Hsieh <khsieh@codeaurora.org> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Link: https://lore.kernel.org/r/1628196295-7382-6-git-send-email-khsieh@codeaurora... Signed-off-by: Rob Clark <robdclark@chromium.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> --- drivers/gpu/drm/msm/dp/dp_panel.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/msm/dp/dp_panel.c b/drivers/gpu/drm/msm/dp/dp_panel.c index 18cec4fc5e0b..2768d1d306f0 100644 --- a/drivers/gpu/drm/msm/dp/dp_panel.c +++ b/drivers/gpu/drm/msm/dp/dp_panel.c @@ -261,7 +261,7 @@ static u8 dp_panel_get_edid_checksum(struct edid *edid) { struct edid *last_block; u8 *raw_edid; - bool is_edid_corrupt; + bool is_edid_corrupt = false; if (!edid) { DRM_ERROR("invalid edid input\n"); @@ -293,7 +293,12 @@ void dp_panel_handle_sink_request(struct dp_panel *dp_panel) panel = container_of(dp_panel, struct dp_panel_private, dp_panel); if (panel->link->sink_request & DP_TEST_LINK_EDID_READ) { - u8 checksum = dp_panel_get_edid_checksum(dp_panel->edid); + u8 checksum; + + if (dp_panel->edid) + checksum = dp_panel_get_edid_checksum(dp_panel->edid); + else + checksum = dp_panel->connector->real_edid_checksum; dp_link_send_edid_checksum(panel->link, checksum); dp_link_send_test_response(panel->link); -- 2.20.1