From: Jessica Zhang <jessica.zhang@oss.qualcomm.com>
To: Rob Clark <robin.clark@oss.qualcomm.com>,
Abhinav Kumar <abhinav.kumar@linux.dev>,
Dmitry Baryshkov <lumag@kernel.org>, Sean Paul <sean@poorly.run>,
Marijn Suijten <marijn.suijten@somainline.org>,
David Airlie <airlied@gmail.com>, Simona Vetter <simona@ffwll.ch>,
Jessica Zhang <jessica.zhang@oss.qualcomm.com>,
Kuogee Hsieh <quic_khsieh@quicinc.com>
Cc: linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org,
freedreno@lists.freedesktop.org, linux-kernel@vger.kernel.org,
Yongxing Mou <quic_yongmou@quicinc.com>
Subject: [PATCH v2 10/12] drm/msm/dp: Return early from atomic_enable() if cable is not connected
Date: Fri, 08 Aug 2025 17:35:22 -0700 [thread overview]
Message-ID: <20250808-hpd-refactor-v2-10-7f4e1e741aa3@oss.qualcomm.com> (raw)
In-Reply-To: <20250808-hpd-refactor-v2-0-7f4e1e741aa3@oss.qualcomm.com>
Replace the ST_MAINLINK_READY check here with a check for sink count.
Since atomic_check() fails if the link isn't ready, we technically don't
need a check against ST_MAINLINK_READY. The hpd_state should also never
really hit ST_DISPLAY_OFF since atomic_enable() shouldn't be called
twice in a row without an atomic_disable() in between.
That being said, it is possible for the cable to be disconnected after
atomic_check() but before atomic_enable(). So let's change this check to
guard against sink_count instead.
Signed-off-by: Jessica Zhang <jessica.zhang@oss.qualcomm.com>
---
drivers/gpu/drm/msm/dp/dp_display.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index dd3fdeaacc91..82f0b6bdbf39 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -1444,7 +1444,7 @@ void msm_dp_bridge_atomic_enable(struct drm_bridge *drm_bridge,
}
hpd_state = msm_dp_display->hpd_state;
- if (hpd_state != ST_DISPLAY_OFF && hpd_state != ST_MAINLINK_READY)
+ if (msm_dp_display->link->sink_count == 0)
return;
rc = msm_dp_display_set_mode(dp, &msm_dp_display->msm_dp_mode);
--
2.50.1
next prev parent reply other threads:[~2025-08-09 0:35 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-08-09 0:35 [PATCH v2 00/12] drm/msm/dp: Drop the HPD state machine Jessica Zhang
2025-08-09 0:35 ` [PATCH v2 01/12] drm/msm/dp: fix HPD state status bit shift value Jessica Zhang
2025-08-09 0:38 ` Dmitry Baryshkov
2025-08-09 0:35 ` [PATCH v2 02/12] drm/msm/dp: Fix the ISR_* enum values Jessica Zhang
2025-08-09 0:35 ` [PATCH v2 03/12] drm/msm/dp: Read DPCD and sink count in bridge detect() Jessica Zhang
2025-08-09 0:44 ` Dmitry Baryshkov
2025-08-09 0:35 ` [PATCH v2 04/12] drm/msm/dp: Move link training to atomic_enable() Jessica Zhang
2025-08-09 0:45 ` Dmitry Baryshkov
2025-08-09 0:53 ` Jessica Zhang
2025-08-09 0:51 ` Dmitry Baryshkov
2025-08-09 0:35 ` [PATCH v2 05/12] drm/msm/dp: Drop EV_USER_NOTIFICATION Jessica Zhang
2025-08-09 2:14 ` Dmitry Baryshkov
2025-08-09 0:35 ` [PATCH v2 06/12] drm/msm/dp: Use drm_bridge_hpd_notify() Jessica Zhang
2025-08-09 6:46 ` Dmitry Baryshkov
2025-08-09 0:35 ` [PATCH v2 07/12] drm/msm/dp: Handle internal HPD IRQ in hpd_notify() Jessica Zhang
2025-08-09 7:05 ` Dmitry Baryshkov
2025-08-09 0:35 ` [PATCH v2 08/12] drm/msm/dp: Drop event waitqueue Jessica Zhang
2025-08-09 7:08 ` Dmitry Baryshkov
2025-08-09 0:35 ` [PATCH v2 09/12] drm/msm/dp: remove redundant checks related to ST_DISPLAY_OFF in plug handler Jessica Zhang
2025-08-09 7:10 ` Dmitry Baryshkov
2025-08-09 0:35 ` Jessica Zhang [this message]
2025-08-09 0:35 ` [PATCH v2 11/12] drm/msm/dp: drop the entire HPD state machine Jessica Zhang
2025-08-09 7:26 ` Dmitry Baryshkov
2025-08-09 0:35 ` [PATCH v2 12/12] drm/msm/dp: Add sink_count and link_ready to debug logs Jessica Zhang
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