From: Wesley Chalmers <Wesley.Chalmers@amd.com>
Date: Mon, 29 Mar 2021 17:36:35 +0000 (-0400)
Subject: drm/amd/display: Do not count I2C DEFERs with AUX DEFERs
X-Git-Tag: v5.14-rc1~114^2~7^2~14
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=95ad72f4ade3db645279dae3bf4ed456ac806a1c;p=thirdparty%2Fkernel%2Flinux.git

drm/amd/display: Do not count I2C DEFERs with AUX DEFERs

[WHY]
DP 2.0 SCR specifies that
"A DPTX shall distinguish I2C_DEFER|AUX_ACK from AUX_DEFER. AUX retries
due to
I2C_DEFER are not counted as part of minimum 7 retires (sic) upon
AUX_DEFER’s"

Signed-off-by: Wesley Chalmers <Wesley.Chalmers@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Anson Jacob <Anson.Jacob@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@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 49cb4e6d64115..28631714f6978 100644
--- a/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c
+++ b/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c
@@ -667,12 +667,13 @@ bool dce_aux_transfer_with_retries(struct ddc_service *ddc,
 			case AUX_TRANSACTION_REPLY_AUX_DEFER:
 				/* polling_timeout_period is in us */
 				defer_time_in_ms += aux110->polling_timeout_period / 1000;
+				++aux_defer_retries;
 				/* fall through */
 			case AUX_TRANSACTION_REPLY_I2C_OVER_AUX_DEFER:
 				retry_on_defer = true;
 				fallthrough;
 			case AUX_TRANSACTION_REPLY_I2C_OVER_AUX_NACK:
-				if (++aux_defer_retries >= AUX_MIN_DEFER_RETRIES
+				if (aux_defer_retries >= AUX_MIN_DEFER_RETRIES
 						&& defer_time_in_ms >= AUX_MAX_DEFER_TIMEOUT_MS) {
 					goto fail;
 				} else {