From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752867AbcD0JOR (ORCPT ); Wed, 27 Apr 2016 05:14:17 -0400 Received: from metis.ext.4.pengutronix.de ([92.198.50.35]:57905 "EHLO metis.ext.4.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752176AbcD0JON (ORCPT ); Wed, 27 Apr 2016 05:14:13 -0400 Message-ID: <1461748450.4044.18.camel@pengutronix.de> Subject: Re: [PATCH v2] drm/imx: imx-ldb: Add DDC support From: Philipp Zabel To: Akshay Bhat Cc: airlied@linux.ie, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Steve Longerbeam Date: Wed, 27 Apr 2016 11:14:10 +0200 In-Reply-To: <1461692430-3976-1-git-send-email-akshay.bhat@timesys.com> References: <1461692430-3976-1-git-send-email-akshay.bhat@timesys.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.12.9-1+b1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 2001:67c:670:100:96de:80ff:fec2:9969 X-SA-Exim-Mail-From: p.zabel@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Akshay, Am Dienstag, den 26.04.2016, 13:40 -0400 schrieb Akshay Bhat: > 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 for picking this up. Please also update the binding docs in Documentation/devicetree/bindings/display/imx/ldb.txt. > 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; For alphabetic and/or aesthetic reasons, would you mind moving this up one line? > 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); If channel->ddc is NULL after this, we should probably warn. > + 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); > } > } > regards Philipp