[PATCH 3/3] drm/msm/dp: promote irq_hpd handle to handle link training correctly

From: Kuogee Hsieh
Date: Tue Nov 03 2020 - 16:49:20 EST


Some dongles require link training done at irq_hpd request instead
of plugin request. This patch promote irq_hpd handler to handle link
training and setup hpd_state correctly.

Fixes: fdaf9a5e3c15 (drm/msm/dp: fixes wrong connection state caused by failure of link training)
Signed-off-by: Kuogee Hsieh <khsieh@xxxxxxxxxxxxxx>
---
drivers/gpu/drm/msm/dp/dp_display.c | 25 +++++++++++++++++++++----
1 file changed, 21 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index 0c0573ad34e6..27e7e27b8b90 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -449,10 +449,9 @@ static int dp_display_handle_irq_hpd(struct dp_display_private *dp)
sink_request = dp->link->sink_request;

if (sink_request & DS_PORT_STATUS_CHANGED) {
- dp_add_event(dp, EV_USER_NOTIFICATION, false, 0);
if (dp_display_is_sink_count_zero(dp)) {
DRM_DEBUG_DP("sink count is zero, nothing to do\n");
- return 0;
+ return -ENOTCONN;
}

return dp_display_process_hpd_high(dp);
@@ -469,7 +468,9 @@ static int dp_display_handle_irq_hpd(struct dp_display_private *dp)
static int dp_display_usbpd_attention_cb(struct device *dev)
{
int rc = 0;
+ u32 sink_request;
struct dp_display_private *dp;
+ struct dp_usbpd *hpd;

if (!dev) {
DRM_ERROR("invalid dev\n");
@@ -483,10 +484,26 @@ static int dp_display_usbpd_attention_cb(struct device *dev)
return -ENODEV;
}

+ hpd = dp->usbpd;
+
/* check for any test request issued by sink */
rc = dp_link_process_request(dp->link);
- if (!rc)
- dp_display_handle_irq_hpd(dp);
+ if (!rc) {
+ sink_request = dp->link->sink_request;
+ if (sink_request & DS_PORT_STATUS_CHANGED) {
+ /* same as unplugged */
+ hpd->hpd_high = 0;
+ dp->hpd_state = ST_DISCONNECT_PENDING;
+ dp_add_event(dp, EV_USER_NOTIFICATION, false, 0);
+ }
+
+ rc = dp_display_handle_irq_hpd(dp);
+
+ if (!rc && (sink_request & DS_PORT_STATUS_CHANGED)) {
+ hpd->hpd_high = 1;
+ dp->hpd_state = ST_CONNECT_PENDING;
+ }
+ }

return rc;
}
--
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