From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932532AbbFQXNQ (ORCPT ); Wed, 17 Jun 2015 19:13:16 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:35178 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932857AbbFQW0S (ORCPT ); Wed, 17 Jun 2015 18:26:18 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Alex Deucher , Kamal Mostafa Subject: [PATCH 3.19.y-ckt 110/146] drm/radeon: retry dcpd fetch Date: Wed, 17 Jun 2015 15:23:35 -0700 Message-Id: <1434579851-1719-111-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1434579851-1719-1-git-send-email-kamal@canonical.com> References: <1434579851-1719-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.19.8-ckt2 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Alex Deucher commit 0f28d1281b6c54cc98746ae61e44e7f540758ed4 upstream. Retry the dpcd fetch several times. Some eDP panels fail several times before the fetch is successful. bug: https://bugs.freedesktop.org/show_bug.cgi?id=73530 Signed-off-by: Alex Deucher Signed-off-by: Kamal Mostafa --- drivers/gpu/drm/radeon/atombios_dp.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/radeon/atombios_dp.c b/drivers/gpu/drm/radeon/atombios_dp.c index 5bf825d..ceab25d 100644 --- a/drivers/gpu/drm/radeon/atombios_dp.c +++ b/drivers/gpu/drm/radeon/atombios_dp.c @@ -405,19 +405,21 @@ bool radeon_dp_getdpcd(struct radeon_connector *radeon_connector) { struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv; u8 msg[DP_DPCD_SIZE]; - int ret; + int ret, i; - ret = drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux, DP_DPCD_REV, msg, - DP_DPCD_SIZE); - if (ret > 0) { - memcpy(dig_connector->dpcd, msg, DP_DPCD_SIZE); + for (i = 0; i < 7; i++) { + ret = drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux, DP_DPCD_REV, msg, + DP_DPCD_SIZE); + if (ret == DP_DPCD_SIZE) { + memcpy(dig_connector->dpcd, msg, DP_DPCD_SIZE); - DRM_DEBUG_KMS("DPCD: %*ph\n", (int)sizeof(dig_connector->dpcd), - dig_connector->dpcd); + DRM_DEBUG_KMS("DPCD: %*ph\n", (int)sizeof(dig_connector->dpcd), + dig_connector->dpcd); - radeon_dp_probe_oui(radeon_connector); + radeon_dp_probe_oui(radeon_connector); - return true; + return true; + } } dig_connector->dpcd[0] = 0; return false; -- 1.9.1