Commit b86e7eef authored Apr 30, 2021 by Nikola Cornij Committed by Alex Deucher May 10, 2021

drm/amd/display: Avoid gpio conflict on MST branch



[Why]
Similar to SST branch, gpio conflict also needs to be avoided on
MST. Without doing so, there is a chance that gpio conflict will
occur if multiple gpio interrupts arrive simultaneously.

[How]
By mutex locking/unlocking &aconnector->hpd_lock,
we won't get gpio conflict when handling hpd.

Signed-off-by: Zhan Liu <zhan.liu@amd.com>
Signed-off-by: Nikola Cornij <nikola.cornij@amd.com>
Reviewed-by: Bhawanpreet Lakha <bhawanpreet.lakha@amd.com>
Acked-by: Zhan Liu <zhan.liu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

parent df0a271c

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

+4 −5

Original line number	Diff line number	Diff line
		@@ -2708,7 +2708,6 @@ static void handle_hpd_rx_irq(void *param)
		* conflict, after implement i2c helper, this mutex should be
		* retired.
		*/
		if (dc_link->type != dc_connection_mst_branch)
		mutex_lock(&aconnector->hpd_lock);

		read_hpd_rx_irq_data(dc_link, &hpd_irq_data);
		@@ -2778,11 +2777,11 @@ static void handle_hpd_rx_irq(void *param)
		}
		#endif

		if (dc_link->type != dc_connection_mst_branch) {
		if (dc_link->type != dc_connection_mst_branch)
		drm_dp_cec_irq(&aconnector->dm_dp_aux.aux);

		mutex_unlock(&aconnector->hpd_lock);
		}
		}

		static void register_hpd_handlers(struct amdgpu_device *adev)
		{