drm/amd/display: Passive DP->HDMI dongle detection fix
authorMichael Strauss <michael.strauss@amd.com>
Thu, 3 Oct 2019 15:54:15 +0000 (11:54 -0400)
committerAlex Deucher <alexander.deucher@amd.com>
Wed, 30 Oct 2019 15:56:16 +0000 (11:56 -0400)
commitbc2fde42e2418808dbfc04de1a6da91d7d31cf1a
tree12182fa5d1e27ac683ed3140b3b1e24450865737
parent7c37d399c2b84d4b79de4d512a38373f1d71ab90
drm/amd/display: Passive DP->HDMI dongle detection fix

[WHY]
i2c_read is called to differentiate passive DP->HDMI and DP->DVI-D dongles
The call is expected to fail in DVI-D case but pass in HDMI case
Some HDMI dongles have a chance to fail as well, causing misdetection as DVI-D

[HOW]
Retry i2c_read to ensure failed result is valid

Signed-off-by: Michael Strauss <michael.strauss@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drivers/gpu/drm/amd/display/dc/core/dc_link_ddc.c