[PATCH v8 17/21] drm/bridge: synopsys: dw-dp: Drop useless reservation of first slot

[Sebastian Reichel]

The origin of this reservation is unclear, but it is a problem in the
atomic_enable code since it potentially races with the audio SDP
reservation once that feature is added. I suppose it was either meant to
be bitmap_zero(), but that is obviously not needed (and would also be a
problem for audio support) or some left-over development code before the
VSC SDP slot was allocated automatically.

>From my tests SDP slot 0 works fine and can be used. If SDP slot 0
really needs to be reserved for some reason, the bit should be set in
the probe function to ensure there are no race conditions.

Signed-off-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxx>
---
 drivers/gpu/drm/bridge/synopsys/dw-dp.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-dp.c b/drivers/gpu/drm/bridge/synopsys/dw-dp.c
index 4d4af6a388b1..193816126e44 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-dp.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-dp.c
@@ -1697,9 +1697,6 @@ static void dw_dp_bridge_atomic_enable(struct drm_bridge *bridge,
 		return;
 	}
 
-	scoped_guard(mutex, &dp->sdp_lock)
-		set_bit(0, dp->sdp_reg_bank);
-
 	ret = dw_dp_link_enable(dp);
 	if (ret < 0) {
 		dev_err(dp->dev, "failed to enable link: %d\n", ret);

-- 
2.53.0