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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 2D9E5C433DB for ; Sun, 21 Mar 2021 18:58:21 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D85F96194C for ; Sun, 21 Mar 2021 18:58:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D85F96194C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=sntech.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 53F436E061; Sun, 21 Mar 2021 18:58:19 +0000 (UTC) Received: from gloria.sntech.de (gloria.sntech.de [185.11.138.130]) by gabe.freedesktop.org (Postfix) with ESMTPS id DD9CB6E061 for ; Sun, 21 Mar 2021 18:58:18 +0000 (UTC) Received: from p508fc3a3.dip0.t-ipconnect.de ([80.143.195.163] helo=phil.localnet) by gloria.sntech.de with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lO3HC-0006z5-By; Sun, 21 Mar 2021 19:58:14 +0100 From: Heiko Stuebner To: Sandy Huang , David Airlie , Daniel Vetter , dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org, Jonathan McDowell Subject: Re: [PATCH] drm/rockchip: Cope with endpoints that haven't been registered yet Date: Sun, 21 Mar 2021 19:58:13 +0100 Message-ID: <3104631.44csPzL39Z@phil> In-Reply-To: <20210316182753.GA25685@earth.li> References: <20210316182753.GA25685@earth.li> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hi Jonathan, Am Dienstag, 16. M=E4rz 2021, 19:27:53 CET schrieb Jonathan McDowell: > The Rockchip RGB CRTC output driver attempts to avoid probing Rockchip > subdrivers to see if they're a connected panel or bridge. However part > of its checks assumes that if no OF platform device is found then it > can't be a valid bridge or panel. This causes issues with I2C controlled > bridges that have not yet been registered to the point they can be > found. > = > Change this to return EPROBE_DEFER instead of ENODEV and don't ignore > such devices. The subsequent call to drm_of_find_panel_or_bridge() will > return EPROBE_DEFER as well if there's actually a valid device we should > wait for. > = > Signed-off-by: Jonathan McDowell > --- > drivers/gpu/drm/rockchip/rockchip_drm_drv.c | 8 ++++++-- > drivers/gpu/drm/rockchip/rockchip_rgb.c | 7 ++++--- > 2 files changed, 10 insertions(+), 5 deletions(-) > = > diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/dr= m/rockchip/rockchip_drm_drv.c > index 212bd87c0c4a..b0d63a566501 100644 > --- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c > +++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c > @@ -270,11 +270,15 @@ int rockchip_drm_endpoint_is_subdriver(struct devic= e_node *ep) > if (!node) > return -ENODEV; > = > - /* status disabled will prevent creation of platform-devices */ > + /* > + * status disabled will prevent creation of platform-devices, > + * but equally we can't rely on the driver having been registered > + * yet (e.g. I2C bridges). > + */ > pdev =3D of_find_device_by_node(node); > of_node_put(node); > if (!pdev) > - return -ENODEV; > + return -EPROBE_DEFER; In general, how does that relate to i2c-bridge-drivers, as of_find_device_by_node supposedly only acts on platform-devices? Also if that points to a disabled bridge (hdmi, etc) that would likely make it probe-defer indefinitly, as that device will never become available? Maybe we could do something like of_device_is_available() which checks the status property of the node. So something like: pdev =3D of_find_device_by_node(node); if (!pdev) { bool avail =3D of_device_is_available(node); of_node_put(node); /* if disabled if (!avail) return -ENODEV; else return -EPROBE_DEFER; } of_node_put(node); Though I still do not understand how that should actually pick up on i2c devices at all. Heiko _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel