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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D806DCF256C for ; Wed, 19 Nov 2025 04:33:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=7/Pwwdu2oM4HR7P2Za/eVgYq3iEyObfL03PwxBvhfL4=; b=d3h7IboO1z+qSxXSjbS6gNVYik a8u+1XhAhxcUiHHo1C2+6hEX+JC+3qrKQ6slb8vx5h0N4pSNAETOtQNKcCDtqYGt6jFyx4SJwHCQL kprXpk/GsW1cFB+jIuVkP723AF3sXQA7ZLlkOyU+vuEUhmDDbkwEgZfRQgSldj3XAmO1w41RaId83 eAOcTQUGekJ25noa8TujxyLIgokHLXUDJMFbL9A2BgtB8FDPgGGeb2bbI0tj1d14dExzjQEFA9owy hHeoUHn3/n2y5hM/ih38n6noiQG1FbFB62+fNR4k80ZoH+79AcDt00GTMxZsNzjSKISmdGF25AovS abqsygKA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vLZsm-00000001neI-2FQh; Wed, 19 Nov 2025 04:33:28 +0000 Received: from perceval.ideasonboard.com ([213.167.242.64]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vLZsk-00000001ncC-0aTd; Wed, 19 Nov 2025 04:33:27 +0000 Received: from pendragon.ideasonboard.com (unknown [205.220.129.225]) by perceval.ideasonboard.com (Postfix) with UTF8SMTPSA id 25D80B5; Wed, 19 Nov 2025 05:31:14 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1763526679; bh=pOisxB3tPa0K5/tNqcYR/OeTkmkwk8Z8S0wlo+6AupQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=kxF0S5kZUsvvw0wJKW8N6wnNELjuWBHspI4m8nki/bfePMBcyASbRxjpLA36Q8y7B WPZPyAqzNkNASh/wBGP3/9d5XnWO/tqy1iwqU2wdW+BbyCT4CXGzwWmtoiuLCnH6cK 4BS5eEyiMbS+ndMBlf+npVIth7IEJeyw1pUmM67s= Date: Wed, 19 Nov 2025 13:32:46 +0900 From: Laurent Pinchart To: Nicolas Frattaroli Cc: Harry Wentland , Leo Li , Rodrigo Siqueira , Alex Deucher , Christian =?utf-8?B?S8O2bmln?= , David Airlie , Simona Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Andrzej Hajda , Neil Armstrong , Robert Foss , Jonas Karlman , Jernej Skrabec , Sandy Huang , Heiko =?utf-8?Q?St=C3=BCbner?= , Andy Yan , Jani Nikula , Rodrigo Vivi , Joonas Lahtinen , Tvrtko Ursulin , kernel@collabora.com, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org Subject: Re: [PATCH v4 04/10] drm/bridge: Act on the DRM color format property Message-ID: <20251119043246.GY10711@pendragon.ideasonboard.com> References: <20251117-color-format-v4-0-0ded72bd1b00@collabora.com> <20251117-color-format-v4-4-0ded72bd1b00@collabora.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20251117-color-format-v4-4-0ded72bd1b00@collabora.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251118_203326_317668_7F95E80E X-CRM114-Status: GOOD ( 26.30 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Nov 17, 2025 at 08:11:48PM +0100, Nicolas Frattaroli wrote: > The new DRM color format property allows userspace to request a specific > color format on a connector. In turn, this fills the connector state's > color_format member to switch color formats. > > Make drm_bridges consider the color_format set in the connector state > during the atomic bridge check. Specifically, reject any output bus > formats that do not correspond to the requested color format. > > Signed-off-by: Nicolas Frattaroli > --- > drivers/gpu/drm/drm_bridge.c | 57 ++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 57 insertions(+) > > diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c > index 8f355df883d8..b7df5cbad832 100644 > --- a/drivers/gpu/drm/drm_bridge.c > +++ b/drivers/gpu/drm/drm_bridge.c > @@ -1052,6 +1052,59 @@ static int select_bus_fmt_recursive(struct drm_bridge *first_bridge, > return ret; > } > > +static bool __pure bus_format_is_color_fmt(u32 bus_fmt, enum drm_color_format fmt) > +{ > + if (bus_fmt == MEDIA_BUS_FMT_FIXED) > + return true; > + > + switch (fmt) { > + case DRM_COLOR_FORMAT_NONE: > + case DRM_COLOR_FORMAT_AUTO: > + return true; > + case DRM_COLOR_FORMAT_RGB444: > + switch (bus_fmt) { > + case MEDIA_BUS_FMT_RGB888_1X24: > + case MEDIA_BUS_FMT_RGB101010_1X30: > + case MEDIA_BUS_FMT_RGB121212_1X36: > + case MEDIA_BUS_FMT_RGB161616_1X48: > + return true; > + default: > + return false; > + } > + case DRM_COLOR_FORMAT_YCBCR444: > + switch (bus_fmt) { > + case MEDIA_BUS_FMT_YUV8_1X24: > + case MEDIA_BUS_FMT_YUV10_1X30: > + case MEDIA_BUS_FMT_YUV12_1X36: > + case MEDIA_BUS_FMT_YUV16_1X48: > + return true; > + default: > + return false; > + } > + case DRM_COLOR_FORMAT_YCBCR422: > + switch (bus_fmt) { > + case MEDIA_BUS_FMT_UYVY8_1X16: > + case MEDIA_BUS_FMT_UYVY10_1X20: > + case MEDIA_BUS_FMT_UYVY12_1X24: > + return true; > + default: > + return false; > + } > + case DRM_COLOR_FORMAT_YCBCR420: > + switch (bus_fmt) { > + case MEDIA_BUS_FMT_UYYVYY8_0_5X24: > + case MEDIA_BUS_FMT_UYYVYY10_0_5X30: > + case MEDIA_BUS_FMT_UYYVYY12_0_5X36: > + case MEDIA_BUS_FMT_UYYVYY16_0_5X48: > + return true; > + default: > + return false; > + } > + } I'd find this more readable: if (fmt == DRM_COLOR_FORMAT_NONE || fmt == DRM_COLOR_FORMAT_AUTO) return true; switch (bus_fmt) { case MEDIA_BUS_FMT_RGB888_1X24: case MEDIA_BUS_FMT_RGB101010_1X30: case MEDIA_BUS_FMT_RGB121212_1X36: case MEDIA_BUS_FMT_RGB161616_1X48: return fmt == DRM_COLOR_FORMAT_RGB444: case MEDIA_BUS_FMT_YUV8_1X24: case MEDIA_BUS_FMT_YUV10_1X30: case MEDIA_BUS_FMT_YUV12_1X36: case MEDIA_BUS_FMT_YUV16_1X48: return fmt == DRM_COLOR_FORMAT_YCBCR444; case MEDIA_BUS_FMT_UYVY8_1X16: case MEDIA_BUS_FMT_UYVY10_1X20: case MEDIA_BUS_FMT_UYVY12_1X24: return fmt == DRM_COLOR_FORMAT_YCBCR422; case MEDIA_BUS_FMT_UYYVYY8_0_5X24: case MEDIA_BUS_FMT_UYYVYY10_0_5X30: case MEDIA_BUS_FMT_UYYVYY12_0_5X36: case MEDIA_BUS_FMT_UYYVYY16_0_5X48: return fmt == DRM_COLOR_FORMAT_YCBCR420; default: return false; } but it could be a matter for personal preference ? I'm also a bit concerned about the if (fmt == DRM_COLOR_FORMAT_NONE || fmt == DRM_COLOR_FORMAT_AUTO) test. What's the difference between NONE and AUTO ? Is it meaningful, or should the two enumerators be merged into a single one ? > + > + return false; > +} > + > /* > * This function is called by &drm_atomic_bridge_chain_check() just before > * calling &drm_bridge_funcs.atomic_check() on all elements of the chain. > @@ -1137,6 +1190,10 @@ drm_atomic_bridge_chain_select_bus_fmts(struct drm_bridge *bridge, > } > > for (i = 0; i < num_out_bus_fmts; i++) { > + if (!bus_format_is_color_fmt(out_bus_fmts[i], conn_state->color_format)) { > + ret = -ENOTSUPP; > + continue; > + } > ret = select_bus_fmt_recursive(bridge, last_bridge, crtc_state, > conn_state, out_bus_fmts[i]); > if (ret != -ENOTSUPP) -- Regards, Laurent Pinchart