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=-9.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,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 88ADBC433DF for ; Sun, 16 Aug 2020 07:46:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6B34E2065C for ; Sun, 16 Aug 2020 07:46:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728728AbgHPHqf (ORCPT ); Sun, 16 Aug 2020 03:46:35 -0400 Received: from asavdk4.altibox.net ([109.247.116.15]:44916 "EHLO asavdk4.altibox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727824AbgHPHqf (ORCPT ); Sun, 16 Aug 2020 03:46:35 -0400 Received: from ravnborg.org (unknown [188.228.123.71]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by asavdk4.altibox.net (Postfix) with ESMTPS id 4582380528; Sun, 16 Aug 2020 09:46:32 +0200 (CEST) Date: Sun, 16 Aug 2020 09:46:30 +0200 From: Sam Ravnborg To: Laurent Pinchart Cc: dri-devel@lists.freedesktop.org, Marek Vasut , devicetree@vger.kernel.org, Guido =?iso-8859-1?Q?G=FCnther?= , Rob Herring , Pengutronix Kernel Team , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH 8/8] drm: mxsfb: Add support for the bus-width DT property Message-ID: <20200816074630.GI1201814@ravnborg.org> References: <20200813012910.13576-1-laurent.pinchart@ideasonboard.com> <20200813012910.13576-9-laurent.pinchart@ideasonboard.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200813012910.13576-9-laurent.pinchart@ideasonboard.com> X-CMAE-Score: 0 X-CMAE-Analysis: v=2.3 cv=aP3eV41m c=1 sm=1 tr=0 a=S6zTFyMACwkrwXSdXUNehg==:117 a=S6zTFyMACwkrwXSdXUNehg==:17 a=kj9zAlcOel0A:10 a=P1BnusSwAAAA:8 a=e5mUnYsNAAAA:8 a=tAAkY-M6p667TXfKU-sA:9 a=tuZZfSq4q83BLy7T:21 a=b_aeklcsRL_HFftP:21 a=CjuIK1q_8ugA:10 a=D0XLA9XvdZm18NrgonBM:22 a=Vxmtnl_E_bksehYqCbjh:22 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hi Laurent. On Thu, Aug 13, 2020 at 04:29:10AM +0300, Laurent Pinchart wrote: > A new bus-width DT property has been introduced in the bindings to allow > overriding the bus width. Support it. > > Signed-off-by: Laurent Pinchart We already reads the bus-width in following files in drm: atmel-hlcdc/atmel_hlcdc_output.c bridge/ti-tfp410.c So this calls for a common helper to do this like: int drm_of_bus_fmt(const struct device_node *ep) { } This helper could then read bus-width, data-shift (if relevant) and return the relevant bus format. I can see that bridge/ti-tfp410.c assumes 12 equals MEDIA_BUS_FMT_RGB888_2X12_LE where as mxsfb assumes 12 is MEDIA_BUS_FMT_RGB444_1X12. I do not know why neither how to handle this difference. Maybe this is something to do with DVI as this is what tfp410 seems to support. Sam > --- > drivers/gpu/drm/mxsfb/mxsfb_drv.c | 26 ++++++++++++++++++++++++++ > drivers/gpu/drm/mxsfb/mxsfb_drv.h | 2 ++ > drivers/gpu/drm/mxsfb/mxsfb_kms.c | 8 ++++++-- > 3 files changed, 34 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/mxsfb/mxsfb_drv.c b/drivers/gpu/drm/mxsfb/mxsfb_drv.c > index 8c549c3931af..fab3aae8cf73 100644 > --- a/drivers/gpu/drm/mxsfb/mxsfb_drv.c > +++ b/drivers/gpu/drm/mxsfb/mxsfb_drv.c > @@ -95,10 +95,36 @@ static int mxsfb_attach_bridge(struct mxsfb_drm_private *mxsfb) > { > struct drm_device *drm = mxsfb->drm; > struct drm_connector_list_iter iter; > + struct device_node *ep; > struct drm_panel *panel; > struct drm_bridge *bridge; > + u32 bus_width = 0; > int ret; > > + ep = of_graph_get_endpoint_by_regs(drm->dev->of_node, 0, 0); > + if (!ep) > + return -ENODEV; > + > + of_property_read_u32(ep, "bus-width", &bus_width); > + of_node_put(ep); > + > + switch (bus_width) { > + case 16: > + mxsfb->bus_format = MEDIA_BUS_FMT_RGB565_1X16; > + break; > + case 18: > + mxsfb->bus_format = MEDIA_BUS_FMT_RGB666_1X18; > + break; > + case 24: > + mxsfb->bus_format = MEDIA_BUS_FMT_RGB888_1X24; > + break; > + case 0: > + break; > + default: > + DRM_DEV_ERROR(drm->dev, "Invalid bus-width %u", bus_width); > + return -ENODEV; > + } > + > ret = drm_of_find_panel_or_bridge(drm->dev->of_node, 0, 0, &panel, > &bridge); > if (ret) > diff --git a/drivers/gpu/drm/mxsfb/mxsfb_drv.h b/drivers/gpu/drm/mxsfb/mxsfb_drv.h > index 399d23e91ed1..c4f7a8a0c891 100644 > --- a/drivers/gpu/drm/mxsfb/mxsfb_drv.h > +++ b/drivers/gpu/drm/mxsfb/mxsfb_drv.h > @@ -32,6 +32,8 @@ struct mxsfb_drm_private { > struct clk *clk_axi; > struct clk *clk_disp_axi; > > + u32 bus_format; > + > struct drm_device *drm; > struct { > struct drm_plane primary; > diff --git a/drivers/gpu/drm/mxsfb/mxsfb_kms.c b/drivers/gpu/drm/mxsfb/mxsfb_kms.c > index b721b8b262ce..6d512f346918 100644 > --- a/drivers/gpu/drm/mxsfb/mxsfb_kms.c > +++ b/drivers/gpu/drm/mxsfb/mxsfb_kms.c > @@ -50,11 +50,15 @@ static void mxsfb_set_formats(struct mxsfb_drm_private *mxsfb) > { > struct drm_device *drm = mxsfb->drm; > const u32 format = mxsfb->crtc.primary->state->fb->format->format; > - u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24; > + u32 bus_format; > u32 ctrl, ctrl1; > > - if (mxsfb->connector->display_info.num_bus_formats) > + if (mxsfb->bus_format) > + bus_format = mxsfb->bus_format; > + else if (mxsfb->connector->display_info.num_bus_formats) > bus_format = mxsfb->connector->display_info.bus_formats[0]; > + else > + bus_format = MEDIA_BUS_FMT_RGB888_1X24; > > DRM_DEV_DEBUG_DRIVER(drm->dev, "Using bus_format: 0x%08X\n", > bus_format); > -- > Regards, > > Laurent Pinchart > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel