From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B902BC43381 for ; Fri, 15 Mar 2019 13:33:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8BBB720854 for ; Fri, 15 Mar 2019 13:33:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728832AbfCONdC (ORCPT ); Fri, 15 Mar 2019 09:33:02 -0400 Received: from relay12.mail.gandi.net ([217.70.178.232]:39035 "EHLO relay12.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727547AbfCONdC (ORCPT ); Fri, 15 Mar 2019 09:33:02 -0400 Received: from aptenodytes (aaubervilliers-681-1-80-102.w90-88.abo.wanadoo.fr [90.88.22.102]) (Authenticated sender: paul.kocialkowski@bootlin.com) by relay12.mail.gandi.net (Postfix) with ESMTPSA id B3AC0200009; Fri, 15 Mar 2019 13:32:56 +0000 (UTC) Message-ID: Subject: Re: [linux-sunxi] [PATCH 3/6] drm/sun4i: dsi: Add bridge support From: Paul Kocialkowski To: jagan@amarulasolutions.com, Andrzej Hajda , Laurent Pinchart , Chen-Yu Tsai , Maxime Ripard , David Airlie , Daniel Vetter , Rob Herring , Mark Rutland Cc: Michael Trimarchi , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@googlegroups.com, linux-amarula@amarulasolutions.com Date: Fri, 15 Mar 2019 14:32:55 +0100 In-Reply-To: <20190315130825.9005-4-jagan@amarulasolutions.com> References: <20190315130825.9005-1-jagan@amarulasolutions.com> <20190315130825.9005-4-jagan@amarulasolutions.com> Organization: Bootlin Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.30.5 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Fri, 2019-03-15 at 18:38 +0530, Jagan Teki wrote: > Some display panels would come up with a non-DSI output which > can have an option to connect DSI interface by means of bridge > convertor. > > This DSI to non-DSI bridge convertor would require a bridge > driver that would communicate the DSI controller for bridge > functionalities. > > So, add support for bridge functionalities in Allwinner DSI > controller. See a few comments below. > Signed-off-by: Jagan Teki > --- > drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 65 +++++++++++++++++++------- > drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h | 1 + > 2 files changed, 49 insertions(+), 17 deletions(-) > > diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c > index 0960b96b62cc..64d74313b842 100644 > --- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c > +++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c > @@ -781,6 +781,9 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder) > if (!IS_ERR(dsi->panel)) > drm_panel_prepare(dsi->panel); > > + if (!IS_ERR(dsi->bridge)) > + drm_bridge_pre_enable(dsi->bridge); > + > /* > * FIXME: This should be moved after the switch to HS mode. > * > @@ -796,6 +799,9 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder) > if (!IS_ERR(dsi->panel)) > drm_panel_enable(dsi->panel); > > + if (!IS_ERR(dsi->bridge)) > + drm_bridge_enable(dsi->bridge); > + > sun6i_dsi_start(dsi, DSI_START_HSC); > > udelay(1000); > @@ -812,6 +818,9 @@ static void sun6i_dsi_encoder_disable(struct drm_encoder *encoder) > if (!IS_ERR(dsi->panel)) { > drm_panel_disable(dsi->panel); > drm_panel_unprepare(dsi->panel); > + } else if (!IS_ERR(dsi->bridge)) { > + drm_bridge_disable(dsi->bridge); > + drm_bridge_post_disable(dsi->bridge); > } > > phy_power_off(dsi->dphy); > @@ -973,11 +982,16 @@ static int sun6i_dsi_attach(struct mipi_dsi_host *host, > struct sun6i_dsi *dsi = host_to_sun6i_dsi(host); > > dsi->device = device; > - dsi->panel = of_drm_find_panel(device->dev.of_node); > - if (IS_ERR(dsi->panel)) > - return PTR_ERR(dsi->panel); > > - dev_info(host->dev, "Attached device %s\n", device->name); > + dsi->bridge = of_drm_find_bridge(device->dev.of_node); > + if (!dsi->bridge) { You are using IS_ERR to check that the bridge is alive in the changes above, but switch to checking that it's non-NULL at this point. Are both guaranteed to be interchangeable? > + dsi->panel = of_drm_find_panel(device->dev.of_node); > + if (IS_ERR(dsi->panel)) > + return PTR_ERR(dsi->panel); > + } You should probably use drm_of_find_panel_or_bridge instead of duplicating the logic here. > + dev_info(host->dev, "Attached %s %s\n", > + dsi->bridge ? "bridge" : "panel", device->name); > > return 0; > } > @@ -1055,8 +1069,10 @@ static int sun6i_dsi_bind(struct device *dev, struct device *master, > struct sun4i_tcon *tcon0 = sun4i_get_tcon0(drm); > int ret; > > - if (!dsi->panel) > + if (!(dsi->panel || dsi->bridge)) { > + dev_info(drm->dev, "No panel or bridge found... DSI output disabled\n"); > return -EPROBE_DEFER; > + } > > dsi->drv = drv; > > @@ -1078,19 +1094,29 @@ static int sun6i_dsi_bind(struct device *dev, struct device *master, > } > dsi->encoder.possible_crtcs = BIT(0); > > - drm_connector_helper_add(&dsi->connector, > - &sun6i_dsi_connector_helper_funcs); > - ret = drm_connector_init(drm, &dsi->connector, > - &sun6i_dsi_connector_funcs, > - DRM_MODE_CONNECTOR_DSI); > - if (ret) { > - dev_err(dsi->dev, > - "Couldn't initialise the DSI connector\n"); > - goto err_cleanup_connector; > + if (dsi->panel) { > + drm_connector_helper_add(&dsi->connector, > + &sun6i_dsi_connector_helper_funcs); > + ret = drm_connector_init(drm, &dsi->connector, > + &sun6i_dsi_connector_funcs, > + DRM_MODE_CONNECTOR_DSI); > + if (ret) { > + dev_err(dsi->dev, > + "Couldn't initialise the DSI connector\n"); > + goto err_cleanup_connector; > + } > + > + drm_connector_attach_encoder(&dsi->connector, &dsi->encoder); > + drm_panel_attach(dsi->panel, &dsi->connector); > } > > - drm_connector_attach_encoder(&dsi->connector, &dsi->encoder); > - drm_panel_attach(dsi->panel, &dsi->connector); > + if (dsi->bridge) { > + ret = drm_bridge_attach(&dsi->encoder, dsi->bridge, NULL); > + if (ret) { > + dev_err(dsi->dev, "Couldn't attach the DSI bridge\n"); > + goto err_cleanup_connector; > + } > + } > > return 0; > > @@ -1104,7 +1130,12 @@ static void sun6i_dsi_unbind(struct device *dev, struct device *master, > { > struct sun6i_dsi *dsi = dev_get_drvdata(dev); > > - drm_panel_detach(dsi->panel); > + if (dsi->panel) > + drm_panel_detach(dsi->panel); > + > + if (dsi->bridge) > + drm_bridge_detach(dsi->bridge); As I mentionned in the first patch, this is quite suspicious since the DRM core should be in charge of detaching the bridge, not the driver. Cheers, Paul > + > } > > static const struct component_ops sun6i_dsi_ops = { > diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h > index 5c4983212f89..76874ff8e3ef 100644 > --- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h > +++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h > @@ -36,6 +36,7 @@ struct sun6i_dsi { > struct sun4i_tcon *tcon; > struct mipi_dsi_device *device; > struct drm_panel *panel; > + struct drm_bridge *bridge; > const struct sun6i_dsi_variant *variant; > }; > > -- > 2.18.0.321.gffc6fa0e3 > -- Paul Kocialkowski, Bootlin Embedded Linux and kernel engineering https://bootlin.com