From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:36854 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751958AbeBBRGp (ORCPT ); Fri, 2 Feb 2018 12:06:45 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Philipp Zabel , Andrzej Hajda , Andrey Gusakov , Sasha Levin Subject: [PATCH 4.9 54/86] drm/bridge: tc358767: do no fail on hi-res displays Date: Fri, 2 Feb 2018 17:58:14 +0100 Message-Id: <20180202140827.266152758@linuxfoundation.org> In-Reply-To: <20180202140822.679101338@linuxfoundation.org> References: <20180202140822.679101338@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andrey Gusakov [ Upstream commit cffd2b16c01c3431a7a7dd62e722af33490fc436 ] Do not fail data rates higher than 2.7 and more than 2 lanes. Try to fall back to 2.7Gbps and 2 lanes. Acked-by: Philipp Zabel Reviewed-by: Andrzej Hajda Signed-off-by: Andrey Gusakov Signed-off-by: Andrzej Hajda Link: https://patchwork.freedesktop.org/patch/msgid/1510073785-16108-2-git-send-email-andrey.gusakov@cogentembedded.com Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/bridge/tc358767.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) --- a/drivers/gpu/drm/bridge/tc358767.c +++ b/drivers/gpu/drm/bridge/tc358767.c @@ -603,8 +603,15 @@ static int tc_get_display_props(struct t ret = drm_dp_link_probe(&tc->aux, &tc->link.base); if (ret < 0) goto err_dpcd_read; - if ((tc->link.base.rate != 162000) && (tc->link.base.rate != 270000)) - goto err_dpcd_inval; + if (tc->link.base.rate != 162000 && tc->link.base.rate != 270000) { + dev_dbg(tc->dev, "Falling to 2.7 Gbps rate\n"); + tc->link.base.rate = 270000; + } + + if (tc->link.base.num_lanes > 2) { + dev_dbg(tc->dev, "Falling to 2 lanes\n"); + tc->link.base.num_lanes = 2; + } ret = drm_dp_dpcd_readb(&tc->aux, DP_MAX_DOWNSPREAD, tmp); if (ret < 0) @@ -637,9 +644,6 @@ static int tc_get_display_props(struct t err_dpcd_read: dev_err(tc->dev, "failed to read DPCD: %d\n", ret); return ret; -err_dpcd_inval: - dev_err(tc->dev, "invalid DPCD\n"); - return -EINVAL; } static int tc_set_video_mode(struct tc_data *tc, struct drm_display_mode *mode)