Per-segment link training requires knowing the number of LTTPRs
(if any) present. Store the count during LTTPRs' initialization.

Signed-off-by: Aleksandrs Vinarskis <alex.vinars...@gmail.com>
---
 drivers/gpu/drm/msm/dp/dp_display.c | 17 +++++++++++------
 drivers/gpu/drm/msm/dp/dp_link.h    |  1 +
 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_display.c 
b/drivers/gpu/drm/msm/dp/dp_display.c
index 5c57c1d7ac60..ab8c1f19dcb4 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -367,16 +367,21 @@ static int msm_dp_display_send_hpd_notification(struct 
msm_dp_display_private *d
        return 0;
 }
 
-static void msm_dp_display_lttpr_init(struct msm_dp_display_private *dp, u8 
*dpcd)
+static int msm_dp_display_lttpr_init(struct msm_dp_display_private *dp, u8 
*dpcd)
 {
-       int rc;
+       int rc, lttpr_count;
 
        if (drm_dp_read_lttpr_common_caps(dp->aux, dpcd, 
dp->link->lttpr_common_caps))
-               return;
+               return 0;
 
-       rc = drm_dp_lttpr_init(dp->aux, 
drm_dp_lttpr_count(dp->link->lttpr_common_caps));
-       if (rc)
+       lttpr_count = drm_dp_lttpr_count(dp->link->lttpr_common_caps);
+       rc = drm_dp_lttpr_init(dp->aux, lttpr_count);
+       if (rc) {
                DRM_ERROR("failed to set LTTPRs transparency mode, rc=%d\n", 
rc);
+               return 0;
+       }
+
+       return lttpr_count;
 }
 
 static int msm_dp_display_process_hpd_high(struct msm_dp_display_private *dp)
@@ -390,7 +395,7 @@ static int msm_dp_display_process_hpd_high(struct 
msm_dp_display_private *dp)
        if (rc)
                goto end;
 
-       msm_dp_display_lttpr_init(dp, dpcd);
+       dp->link->lttpr_count = msm_dp_display_lttpr_init(dp, dpcd);
 
        rc = msm_dp_panel_read_sink_caps(dp->panel, connector);
        if (rc)
diff --git a/drivers/gpu/drm/msm/dp/dp_link.h b/drivers/gpu/drm/msm/dp/dp_link.h
index c47d75cfc720..ba47c6d19fbf 100644
--- a/drivers/gpu/drm/msm/dp/dp_link.h
+++ b/drivers/gpu/drm/msm/dp/dp_link.h
@@ -62,6 +62,7 @@ struct msm_dp_link_phy_params {
 
 struct msm_dp_link {
        u8 lttpr_common_caps[DP_LTTPR_COMMON_CAP_SIZE];
+       int lttpr_count;
 
        u32 sink_request;
        u32 test_response;
-- 
2.45.2

Reply via email to