drm/amd/display: Use udelay when waiting between aux retries

[Why]
"IRQ_HPD Pulse Length Test" DP compliance test
fails. Test complains that certain DPCD registers
are not read within 100 ms.

[How]
msleep is inaccurate for small values. Used udelay
instead for accuracy.

Signed-off-by: John Barberiz <John.Barberiz@amd.com>
Reviewed-by: Wenjing Liu <Wenjing.Liu@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c b/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c
index adbb22224e1afb7c56da56c95f1af6c131621cc2..4febf4ef7240e6aef2610063b55f3aee636bbca0 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c
+++ b/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c
@@ -516,7 +516,7 @@ bool dce_aux_transfer_with_retries(struct ddc_service *ddc,
                        }
                }
 
-               msleep(1);
+               udelay(1000);
        }
        return false;
 }