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=-6.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 B8E31C433E1 for ; Wed, 24 Jun 2020 22:47:59 +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 8C5B32065D for ; Wed, 24 Jun 2020 22:47:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="uzkvI7/3" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8C5B32065D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ideasonboard.com 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 0F56C6E0D3; Wed, 24 Jun 2020 22:47:59 +0000 (UTC) Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) by gabe.freedesktop.org (Postfix) with ESMTPS id 3C27E6E0D3 for ; Wed, 24 Jun 2020 22:47:57 +0000 (UTC) Received: from pendragon.ideasonboard.com (81-175-216-236.bb.dnainternet.fi [81.175.216.236]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 21CD22A8; Thu, 25 Jun 2020 00:47:55 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1593038875; bh=1phuELyAWC9kiLJ0qWlCpumeJ0WEjE52rPQPBrntzdU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=uzkvI7/3NU65bdE16DR0ZnU58cC2uQGTek3RWQs5WYtZruSJi4ZeMZ8vPOp7xyzIu ho/8fi0PXgpTC9SUpq5vmEzNsH43eQZZ5veeuix7YW2OyDpLI5A8xoREXUj58kEfGh /SGkLTs9eACNuCF4tpF4Rm3dKHMiucQXs88hfGIk= Date: Thu, 25 Jun 2020 01:47:54 +0300 From: Laurent Pinchart To: Daniel Vetter Subject: Re: [PATCH 27/27] drm: Add default modes for connectors in unknown state Message-ID: <20200624224754.GJ5980@pendragon.ideasonboard.com> References: <20200526011505.31884-1-laurent.pinchart+renesas@ideasonboard.com> <20200526011505.31884-28-laurent.pinchart+renesas@ideasonboard.com> <20200621084000.GM74146@ravnborg.org> <20200624011209.GU5870@pendragon.ideasonboard.com> <20200624072304.GT20149@phenom.ffwll.local> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200624072304.GT20149@phenom.ffwll.local> 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: , Cc: Jernej Skrabec , Laurent Pinchart , Jonas Karlman , Neil Armstrong , Kieran Bingham , dri-devel@lists.freedesktop.org, linux-renesas-soc@vger.kernel.org, Andrzej Hajda , Thomas Zimmermann , Sam Ravnborg Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hi Daniel, On Wed, Jun 24, 2020 at 09:23:04AM +0200, Daniel Vetter wrote: > On Wed, Jun 24, 2020 at 04:12:09AM +0300, Laurent Pinchart wrote: > > On Sun, Jun 21, 2020 at 10:40:00AM +0200, Sam Ravnborg wrote: > > > On Tue, May 26, 2020 at 04:15:05AM +0300, Laurent Pinchart wrote: > > > > The DRM CRTC helpers add default modes to connectors in the connected > > > > state if no mode can be retrieved from the connector. This behaviour is > > > > useful for VGA or DVI outputs that have no connected DDC bus. However, > > > > in such cases, the status of the output usually can't be retrieved and > > > > is reported as connector_status_unknown. > > > > > > > > Extend the addition of default modes to connectors in an unknown state > > > > to support outputs that can retrieve neither the modes nor the > > > > connection status. > > > > > > > > Signed-off-by: Laurent Pinchart > > > > > > From your description sounds like an OK approach. > > > But this is not something I feel too familiar with. > > > Acked-by: Sam Ravnborg > > > > Thanks for the ack. I'd like to have Daniel's (CC'ed) feedback on this > > too. > > Makes sense, and at least pre-coffee me can't immediately think of a > scenario where we're going to regret this. _unknown status is pretty much > limited to old VGA and similar things where load detect somehow isn't well > supported by the hw. > > Reviewed-by: Daniel Vetter > > > > > --- > > > > drivers/gpu/drm/drm_probe_helper.c | 3 ++- > > > > include/drm/drm_modeset_helper_vtables.h | 8 +++++++- > > > > 2 files changed, 9 insertions(+), 2 deletions(-) > > > > > > > > diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c > > > > index f5d141e0400f..9055d9573c90 100644 > > > > --- a/drivers/gpu/drm/drm_probe_helper.c > > > > +++ b/drivers/gpu/drm/drm_probe_helper.c > > > > @@ -491,7 +491,8 @@ int drm_helper_probe_single_connector_modes(struct drm_connector *connector, > > > > if (count == 0 && connector->status == connector_status_connected) > > > > count = drm_add_override_edid_modes(connector); > > > > > > > > - if (count == 0 && connector->status == connector_status_connected) > > > > + if (count == 0 && (connector->status == connector_status_connected || > > > > + connector->status == connector_status_unknown)) > > > > count = drm_add_modes_noedid(connector, 1024, 768); > > > > count += drm_helper_probe_add_cmdline_mode(connector); > > > > if (count == 0) > > > > diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h > > > > index 421a30f08463..afe55e2e93d2 100644 > > > > --- a/include/drm/drm_modeset_helper_vtables.h > > > > +++ b/include/drm/drm_modeset_helper_vtables.h > > > > @@ -876,13 +876,19 @@ struct drm_connector_helper_funcs { > > > > * The usual way to implement this is to cache the EDID retrieved in the > > > > * probe callback somewhere in the driver-private connector structure. > > > > * In this function drivers then parse the modes in the EDID and add > > > > - * them by calling drm_add_edid_modes(). But connectors that driver a > > > > + * them by calling drm_add_edid_modes(). But connectors that drive a > > > > * fixed panel can also manually add specific modes using > > > > * drm_mode_probed_add(). Drivers which manually add modes should also > > > > * make sure that the &drm_connector.display_info, > > > > * &drm_connector.width_mm and &drm_connector.height_mm fields are > > > > * filled in. > > > > * > > > > + * Note that the caller function will automatically add standard VESA > > > > + * DMT modes up to 1024x768 if the .get_modes() helper operation returns > > > > + * no mode and if the connector status is connector_status_connected or > > > > + * connector_status_unknown. There is no need to call > > > > + * drm_add_edid_modes() manually in that case. > > Hm calling drm_add_edid_modes if you have no edid is a bit a funny idea > ... Personally I'd just leave out the last sentence, I think that only > confuses readers. Or I'm not grasphing what you're trying to tell here. Sorry, I meant drm_add_modes_noedid(). Is that clearer ? > r-b with or without this change since imo super tiny nit. > > > > > + * > > > > * Virtual drivers that just want some standard VESA mode with a given > > > > * resolution can call drm_add_modes_noedid(), and mark the preferred > > > > * one using drm_set_preferred_mode(). -- Regards, Laurent Pinchart _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel