When using type-c to type-c to connect to the monitor, the sound plays normally. If you unplug the type-c and connect the type-c to hdmi dongle to the monitor, there will be noise. By capturing the audio data, it is found that the data position is messy, and there is no error in the data. Through experiments, it can be restored by resetting the SDP path when unplugging it. Signed-off-by: Liankun Yang <liankun.yang@xxxxxxxxxxxx> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx> --- Changes in V3: - No change. Per suggestion from the previous thread: https://patchwork.kernel.org/project/linux-mediatek/patch/20240923132521.22785-1-liankun.yang@xxxxxxxxxxxx/ Changes in V2: - Fix build error. Per suggestion from the previous thread: https://patchwork.kernel.org/project/linux-mediatek/patch/20240923133610.23728-1-liankun.yang@xxxxxxxxxxxx/ --- drivers/gpu/drm/mediatek/mtk_dp.c | 15 +++++++++++++++ drivers/gpu/drm/mediatek/mtk_dp_reg.h | 1 + 2 files changed, 16 insertions(+) diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/mtk_dp.c index d8796a904eca..4003bd83f64e 100644 --- a/drivers/gpu/drm/mediatek/mtk_dp.c +++ b/drivers/gpu/drm/mediatek/mtk_dp.c @@ -1052,6 +1052,18 @@ static void mtk_dp_digital_sw_reset(struct mtk_dp *mtk_dp) 0, DP_TX_TRANSMITTER_4P_RESET_SW_DP_TRANS_P0); } +static void mtk_dp_sdp_path_reset(struct mtk_dp *mtk_dp) +{ + mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3004, + SDP_RESET_SW_DP_ENC0_P0, + SDP_RESET_SW_DP_ENC0_P0); + + /* Wait for sdp path reset to complete */ + usleep_range(1000, 5000); + mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3004, + 0, SDP_RESET_SW_DP_ENC0_P0); +} + static void mtk_dp_set_lanes(struct mtk_dp *mtk_dp, int lanes) { mtk_dp_update_bits(mtk_dp, MTK_DP_TRANS_P0_35F0, @@ -2314,6 +2326,9 @@ static void mtk_dp_bridge_atomic_disable(struct drm_bridge *bridge, DP_PWR_STATE_BANDGAP_TPLL, DP_PWR_STATE_MASK); + /* SDP path reset sw*/ + mtk_dp_sdp_path_reset(mtk_dp); + /* Ensure the sink is muted */ msleep(20); } diff --git a/drivers/gpu/drm/mediatek/mtk_dp_reg.h b/drivers/gpu/drm/mediatek/mtk_dp_reg.h index 709b79480693..8ad7a9cc259e 100644 --- a/drivers/gpu/drm/mediatek/mtk_dp_reg.h +++ b/drivers/gpu/drm/mediatek/mtk_dp_reg.h @@ -86,6 +86,7 @@ #define MTK_DP_ENC0_P0_3004 0x3004 #define VIDEO_M_CODE_SEL_DP_ENC0_P0_MASK BIT(8) #define DP_TX_ENCODER_4P_RESET_SW_DP_ENC0_P0 BIT(9) +#define SDP_RESET_SW_DP_ENC0_P0 BIT(13) #define MTK_DP_ENC0_P0_3010 0x3010 #define HTOTAL_SW_DP_ENC0_P0_MASK GENMASK(15, 0) #define MTK_DP_ENC0_P0_3014 0x3014 -- 2.45.2
