[PATCH v4 12/13] drm: zynqmp_dp: Take dp->lock in zynqmp_dp_hpd_work_func

From: Sean Anderson
Date: Tue Apr 23 2024 - 13:21:37 EST


Add a non-locking version of zynqmp_dp_bridge_detect and use it in
zynqmp_dp_hpd_work_func so we can take the lock explicitly. This will
make it easier to check for hpd_ignore when we add debugfs support.

Signed-off-by: Sean Anderson <sean.anderson@xxxxxxxxx>
---

(no changes since v3)

Changes in v3:
- New

drivers/gpu/drm/xlnx/zynqmp_dp.c | 24 ++++++++++++++++++------
1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/xlnx/zynqmp_dp.c b/drivers/gpu/drm/xlnx/zynqmp_dp.c
index d5ee165046f8..fe002fef4662 100644
--- a/drivers/gpu/drm/xlnx/zynqmp_dp.c
+++ b/drivers/gpu/drm/xlnx/zynqmp_dp.c
@@ -1552,14 +1552,13 @@ static int zynqmp_dp_bridge_atomic_check(struct drm_bridge *bridge,
return 0;
}

-static enum drm_connector_status zynqmp_dp_bridge_detect(struct drm_bridge *bridge)
+static enum drm_connector_status __zynqmp_dp_bridge_detect(struct zynqmp_dp *dp)
{
- struct zynqmp_dp *dp = bridge_to_dp(bridge);
struct zynqmp_dp_link_config *link_config = &dp->link_config;
u32 state, i;
int ret;

- mutex_lock(&dp->lock);
+ lockdep_assert_held(&dp->lock);

/*
* This is from heuristic. It takes some delay (ex, 100 ~ 500 msec) to
@@ -1588,16 +1587,26 @@ static enum drm_connector_status zynqmp_dp_bridge_detect(struct drm_bridge *brid
dp->num_lanes);

dp->status = connector_status_connected;
- mutex_unlock(&dp->lock);
return connector_status_connected;
}

disconnected:
dp->status = connector_status_disconnected;
- mutex_unlock(&dp->lock);
return connector_status_disconnected;
}

+static enum drm_connector_status zynqmp_dp_bridge_detect(struct drm_bridge *bridge)
+{
+ struct zynqmp_dp *dp = bridge_to_dp(bridge);
+ enum drm_connector_status ret;
+
+ mutex_lock(&dp->lock);
+ ret = __zynqmp_dp_bridge_detect(dp);
+ mutex_unlock(&dp->lock);
+
+ return ret;
+}
+
static const struct drm_edid *zynqmp_dp_bridge_edid_read(struct drm_bridge *bridge,
struct drm_connector *connector)
{
@@ -1651,7 +1660,10 @@ static void zynqmp_dp_hpd_work_func(struct work_struct *work)
struct zynqmp_dp *dp = container_of(work, struct zynqmp_dp, hpd_work);
enum drm_connector_status status;

- status = zynqmp_dp_bridge_detect(&dp->bridge);
+ mutex_lock(&dp->lock);
+ status = __zynqmp_dp_bridge_detect(dp);
+ mutex_unlock(&dp->lock);
+
drm_bridge_hpd_notify(&dp->bridge, status);
}

--
2.35.1.1320.gc452695387.dirty