From patchwork Wed Jun 17 22:23:35 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamal Mostafa X-Patchwork-Id: 485870 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id CAA481401EF; Thu, 18 Jun 2015 08:31:43 +1000 (AEST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1Z5Lrw-0002O3-GO; Wed, 17 Jun 2015 22:31:40 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1Z5Lmj-0007lQ-5D for kernel-team@lists.ubuntu.com; Wed, 17 Jun 2015 22:26:17 +0000 Received: from [10.172.68.52] (helo=fourier) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.76) (envelope-from ) id 1Z5Lmi-0003Gu-Uh; Wed, 17 Jun 2015 22:26:17 +0000 Received: from kamal by fourier with local (Exim 4.82) (envelope-from ) id 1Z5Lmg-0000es-MN; Wed, 17 Jun 2015 15:26:14 -0700 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com 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 Cc: Alex Deucher , Kamal Mostafa X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 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;