6.6-stable review patch. If anyone has any objections, please let me know.
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From: Kuogee Hsieh quic_khsieh@quicinc.com
[ Upstream commit 77e8aad5519e04f6c1e132aaec1c5f8faf41844f ]
Since the value of DP_TEST_BIT_DEPTH_8 is already left shifted, in the BPC unknown case, the additional shift causes spill over to the other bits of the [DP_CONFIGURATION_CTRL] register. Fix this by changing the return value of dp_link_get_test_bits_depth() in the BPC unknown case to (DP_TEST_BIT_DEPTH_8 >> DP_TEST_BIT_DEPTH_SHIFT).
Fixes: c943b4948b58 ("drm/msm/dp: add displayPort driver support") Signed-off-by: Kuogee Hsieh quic_khsieh@quicinc.com Reviewed-by: Abhinav Kumar quic_abhinavk@quicinc.com Reviewed-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Patchwork: https://patchwork.freedesktop.org/patch/573989/ Link: https://lore.kernel.org/r/1704917931-30133-1-git-send-email-quic_khsieh@quic... [quic_abhinavk@quicinc.com: fix minor checkpatch warning to align with opening braces] Signed-off-by: Abhinav Kumar quic_abhinavk@quicinc.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/msm/dp/dp_ctrl.c | 5 ----- drivers/gpu/drm/msm/dp/dp_link.c | 10 +++++++--- 2 files changed, 7 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c index 77a8d9366ed7..fb588fde298a 100644 --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c @@ -135,11 +135,6 @@ static void dp_ctrl_config_ctrl(struct dp_ctrl_private *ctrl) tbd = dp_link_get_test_bits_depth(ctrl->link, ctrl->panel->dp_mode.bpp);
- if (tbd == DP_TEST_BIT_DEPTH_UNKNOWN) { - pr_debug("BIT_DEPTH not set. Configure default\n"); - tbd = DP_TEST_BIT_DEPTH_8; - } - config |= tbd << DP_CONFIGURATION_CTRL_BPC_SHIFT;
/* Num of Lanes */ diff --git a/drivers/gpu/drm/msm/dp/dp_link.c b/drivers/gpu/drm/msm/dp/dp_link.c index 6375daaeb98e..487867979557 100644 --- a/drivers/gpu/drm/msm/dp/dp_link.c +++ b/drivers/gpu/drm/msm/dp/dp_link.c @@ -1211,6 +1211,9 @@ void dp_link_reset_phy_params_vx_px(struct dp_link *dp_link) u32 dp_link_get_test_bits_depth(struct dp_link *dp_link, u32 bpp) { u32 tbd; + struct dp_link_private *link; + + link = container_of(dp_link, struct dp_link_private, dp_link);
/* * Few simplistic rules and assumptions made here: @@ -1228,12 +1231,13 @@ u32 dp_link_get_test_bits_depth(struct dp_link *dp_link, u32 bpp) tbd = DP_TEST_BIT_DEPTH_10; break; default: - tbd = DP_TEST_BIT_DEPTH_UNKNOWN; + drm_dbg_dp(link->drm_dev, "bpp=%d not supported, use bpc=8\n", + bpp); + tbd = DP_TEST_BIT_DEPTH_8; break; }
- if (tbd != DP_TEST_BIT_DEPTH_UNKNOWN) - tbd = (tbd >> DP_TEST_BIT_DEPTH_SHIFT); + tbd = (tbd >> DP_TEST_BIT_DEPTH_SHIFT);
return tbd; }