Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752603AbcDZRl0 (ORCPT ); Tue, 26 Apr 2016 13:41:26 -0400 Received: from mail-qg0-f45.google.com ([209.85.192.45]:34183 "EHLO mail-qg0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752205AbcDZRlZ (ORCPT ); Tue, 26 Apr 2016 13:41:25 -0400 From: Akshay Bhat To: p.zabel@pengutronix.de Cc: airlied@linux.ie, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Steve Longerbeam , Akshay Bhat Subject: [PATCH v2] drm/imx: imx-ldb: Add DDC support Date: Tue, 26 Apr 2016 13:40:30 -0400 Message-Id: <1461692430-3976-1-git-send-email-akshay.bhat@timesys.com> X-Mailer: git-send-email 2.8.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3238 Lines: 108 From: Steve Longerbeam Add support for reading EDID over Display Data Channel. If no DDC adapter is available, falls back to hardcoded EDID or display-timings node as before. Signed-off-by: Steve Longerbeam Signed-off-by: Akshay Bhat Acked-by: Philipp Zabel --- Hi Philipp, I found this patch to add DDC support to imx-ldb at: https://patchwork.kernel.org/patch/5207231/ Looks like it never made it to the upstream kernel. I have rebased this on 4.6-rc5 and tested the same. Thanks, Akshay v1 -> v2: Rebase to 4.6-rc5 Add check for channel->panel before fallback to display-timings node drivers/gpu/drm/imx/imx-ldb.c | 38 ++++++++++++++++++++++++++++++-------- 1 file changed, 30 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/imx/imx-ldb.c b/drivers/gpu/drm/imx/imx-ldb.c index a58eee5..67706c9 100644 --- a/drivers/gpu/drm/imx/imx-ldb.c +++ b/drivers/gpu/drm/imx/imx-ldb.c @@ -59,6 +59,7 @@ struct imx_ldb_channel { struct drm_encoder encoder; struct drm_panel *panel; struct device_node *child; + struct i2c_adapter *ddc; int chno; void *edid; int edid_len; @@ -107,6 +108,9 @@ static int imx_ldb_connector_get_modes(struct drm_connector *connector) return num_modes; } + if (!imx_ldb_ch->edid && imx_ldb_ch->ddc) + imx_ldb_ch->edid = drm_get_edid(connector, imx_ldb_ch->ddc); + if (imx_ldb_ch->edid) { drm_mode_connector_update_edid_property(connector, imx_ldb_ch->edid); @@ -554,6 +558,7 @@ static int imx_ldb_bind(struct device *dev, struct device *master, void *data) for_each_child_of_node(np, child) { struct imx_ldb_channel *channel; struct device_node *port; + struct device_node *ddc_node; ret = of_property_read_u32(child, "reg", &i); if (ret || i < 0 || i > 1) @@ -595,14 +600,30 @@ static int imx_ldb_bind(struct device *dev, struct device *master, void *data) } } - edidp = of_get_property(child, "edid", &channel->edid_len); - if (edidp) { - channel->edid = kmemdup(edidp, channel->edid_len, - GFP_KERNEL); - } else if (!channel->panel) { - ret = of_get_drm_display_mode(child, &channel->mode, 0); - if (!ret) - channel->mode_valid = 1; + ddc_node = of_parse_phandle(child, "ddc-i2c-bus", 0); + if (ddc_node) { + channel->ddc = of_find_i2c_adapter_by_node(ddc_node); + of_node_put(ddc_node); + } + + if (!channel->ddc) { + /* if no DDC available, fallback to hardcoded EDID */ + dev_dbg(dev, "no ddc available\n"); + + edidp = of_get_property(child, "edid", + &channel->edid_len); + if (edidp) { + channel->edid = kmemdup(edidp, + channel->edid_len, + GFP_KERNEL); + } else if (!channel->panel) { + /* fallback to display-timings node */ + ret = of_get_drm_display_mode(child, + &channel->mode, + 0); + if (!ret) + channel->mode_valid = 1; + } } channel->bus_format = of_get_bus_format(dev, child); @@ -647,6 +668,7 @@ static void imx_ldb_unbind(struct device *dev, struct device *master, channel->encoder.funcs->destroy(&channel->encoder); kfree(channel->edid); + i2c_put_adapter(channel->ddc); } } -- 2.8.1