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From 74c19b3e67b5160f55bccf69148e231183a2bf07 Mon Sep 17 00:00:00 2001
From: John Barberiz <John.Barberiz@amd.com>
Date: Wed, 16 Jan 2019 17:21:31 -0500
Subject: [PATCH 1196/2940] 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.

Change-Id: I4990fc56c7632fba373f2dbf64ac803d64619529
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>
---
 drivers/gpu/drm/amd/display/dc/dce/dce_aux.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

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 adbb22224e1a..4febf4ef7240 100644
--- 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;
 }
-- 
2.17.1