Add checking aux read/write status at both dp_link_parse_sink_count() and dp_link_parse_sink_status_filed() to avoid long timeout delay if dp aux read/write failed at timeout due to cable unplugged. Also make sure dp controller had been initialized before start dpcd read and write.

Changes in V4: -- split this patch as stand alone patch

Changes in v5: -- rebase on msm-next branch

Changes in v6: -- add more details commit text

Signed-off-by: Kuogee Hsieh quic_khsieh@quicinc.com Reviewed-by: Stephen Boyd swboyd@chromium.org Tested-by: Stephen Boyd swboyd@chromium.org --- drivers/gpu/drm/msm/dp/dp_display.c | 12 +++++++++--- drivers/gpu/drm/msm/dp/dp_link.c | 19 ++++++++++++++----- 2 files changed, 23 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c index 3d61459..0766752 100644 --- a/drivers/gpu/drm/msm/dp/dp_display.c +++ b/drivers/gpu/drm/msm/dp/dp_display.c @@ -692,9 +692,15 @@ static int dp_irq_hpd_handle(struct dp_display_private *dp, u32 data) return 0; }

- ret = dp_display_usbpd_attention_cb(&dp->pdev->dev); - if (ret == -ECONNRESET) { /* cable unplugged */ - dp->core_initialized = false; + /* + * dp core (ahb/aux clks) must be initialized before + * irq_hpd be handled + */ + if (dp->core_initialized) { + ret = dp_display_usbpd_attention_cb(&dp->pdev->dev); + if (ret == -ECONNRESET) { /* cable unplugged */ + dp->core_initialized = false; + } } DRM_DEBUG_DP("hpd_state=%d\n", state);

diff --git a/drivers/gpu/drm/msm/dp/dp_link.c b/drivers/gpu/drm/msm/dp/dp_link.c index a5bdfc5..d4d31e5 100644 --- a/drivers/gpu/drm/msm/dp/dp_link.c +++ b/drivers/gpu/drm/msm/dp/dp_link.c @@ -737,18 +737,25 @@ static int dp_link_parse_sink_count(struct dp_link *dp_link) return 0; }

-static void dp_link_parse_sink_status_field(struct dp_link_private *link) +static int dp_link_parse_sink_status_field(struct dp_link_private *link) { int len = 0;

link->prev_sink_count = link->dp_link.sink_count; - dp_link_parse_sink_count(&link->dp_link); + len = dp_link_parse_sink_count(&link->dp_link); + if (len < 0) { + DRM_ERROR("DP parse sink count failed\n"); + return len; + }

len = drm_dp_dpcd_read_link_status(link->aux, link->link_status); - if (len < DP_LINK_STATUS_SIZE) + if (len < DP_LINK_STATUS_SIZE) { DRM_ERROR("DP link status read failed\n"); - dp_link_parse_request(link); + return len; + } + + return dp_link_parse_request(link); }

/** @@ -1023,7 +1030,9 @@ int dp_link_process_request(struct dp_link *dp_link)

dp_link_reset_data(link);

- dp_link_parse_sink_status_field(link); + ret = dp_link_parse_sink_status_field(link); + if (ret) + return ret;

if (link->request.test_requested == DP_TEST_LINK_EDID_READ) { dp_link->sink_request |= DP_TEST_LINK_EDID_READ;