Some DP sinkers prefer to use tps4 instead of tps3 during training #2.
This patch will use tps4 to perform link training #2 if sinker's DPCD
supports it.
Changes in V2:
-- replace  dp_catalog_ctrl_set_pattern() with  dp_catalog_ctrl_set_pattern_state_bit()
Changes in V3:
-- change state_ctrl_bits type to u32 and pattern type to u8
Changes in V4:
-- align } else if { and } else {
Changes in v10:
--  group into one series
Changes in v11:
-- drop drm/msm/dp: dp_link_parse_sink_count() return immediately if aux read
Signed-off-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/1642531648-8448-4-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
 
        dp_write_p0(catalog, MMSS_DP_DSC_DTO, 0x0);
 }
 
-int dp_catalog_ctrl_set_pattern(struct dp_catalog *dp_catalog,
-                                       u32 pattern)
+int dp_catalog_ctrl_set_pattern_state_bit(struct dp_catalog *dp_catalog,
+                                       u32 state_bit)
 {
        int bit, ret;
        u32 data;
        struct dp_catalog_private *catalog = container_of(dp_catalog,
                                struct dp_catalog_private, dp_catalog);
 
-       bit = BIT(pattern - 1);
-       DRM_DEBUG_DP("hw: bit=%d train=%d\n", bit, pattern);
+       bit = BIT(state_bit - 1);
+       DRM_DEBUG_DP("hw: bit=%d train=%d\n", bit, state_bit);
        dp_catalog_ctrl_state_ctrl(dp_catalog, bit);
 
-       bit = BIT(pattern - 1) << DP_MAINLINK_READY_LINK_TRAINING_SHIFT;
+       bit = BIT(state_bit - 1) << DP_MAINLINK_READY_LINK_TRAINING_SHIFT;
 
        /* Poll for mainlink ready status */
        ret = readx_poll_timeout(readl, catalog->io->dp_controller.link.base +
                                        data, data & bit,
                                        POLLING_SLEEP_US, POLLING_TIMEOUT_US);
        if (ret < 0) {
-               DRM_ERROR("set pattern for link_train=%d failed\n", pattern);
+               DRM_ERROR("set state_bit for link_train=%d failed\n", state_bit);
                return ret;
        }
        return 0;
 
 void dp_catalog_ctrl_config_misc(struct dp_catalog *dp_catalog, u32 cc, u32 tb);
 void dp_catalog_ctrl_config_msa(struct dp_catalog *dp_catalog, u32 rate,
                                u32 stream_rate_khz, bool fixed_nvid);
-int dp_catalog_ctrl_set_pattern(struct dp_catalog *dp_catalog, u32 pattern);
+int dp_catalog_ctrl_set_pattern_state_bit(struct dp_catalog *dp_catalog, u32 pattern);
 void dp_catalog_ctrl_reset(struct dp_catalog *dp_catalog);
 bool dp_catalog_ctrl_mainlink_ready(struct dp_catalog *dp_catalog);
 void dp_catalog_ctrl_enable_irq(struct dp_catalog *dp_catalog, bool enable);
 
 
        *training_step = DP_TRAINING_1;
 
-       ret = dp_catalog_ctrl_set_pattern(ctrl->catalog, DP_TRAINING_PATTERN_1);
+       ret = dp_catalog_ctrl_set_pattern_state_bit(ctrl->catalog, 1);
        if (ret)
                return ret;
        dp_ctrl_train_pattern_set(ctrl, DP_TRAINING_PATTERN_1 |
                        int *training_step)
 {
        int tries = 0, ret = 0;
-       char pattern;
+       u8 pattern;
+       u32 state_ctrl_bit;
        int const maximum_retries = 5;
        u8 link_status[DP_LINK_STATUS_SIZE];
 
 
        *training_step = DP_TRAINING_2;
 
-       if (drm_dp_tps3_supported(ctrl->panel->dpcd))
+       if (drm_dp_tps4_supported(ctrl->panel->dpcd)) {
+               pattern = DP_TRAINING_PATTERN_4;
+               state_ctrl_bit = 4;
+       } else if (drm_dp_tps3_supported(ctrl->panel->dpcd)) {
                pattern = DP_TRAINING_PATTERN_3;
-       else
+               state_ctrl_bit = 3;
+       } else {
                pattern = DP_TRAINING_PATTERN_2;
+               state_ctrl_bit = 2;
+       }
 
-       ret = dp_catalog_ctrl_set_pattern(ctrl->catalog, pattern);
+       ret = dp_catalog_ctrl_set_pattern_state_bit(ctrl->catalog, state_ctrl_bit);
        if (ret)
                return ret;