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=-10.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 AA236C4338F for ; Tue, 27 Jul 2021 09:21:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 80E3D60E09 for ; Tue, 27 Jul 2021 09:21:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236004AbhG0JVA (ORCPT ); Tue, 27 Jul 2021 05:21:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33530 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235897AbhG0JU6 (ORCPT ); Tue, 27 Jul 2021 05:20:58 -0400 Received: from mail-wm1-x32a.google.com (mail-wm1-x32a.google.com [IPv6:2a00:1450:4864:20::32a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DF10DC061757 for ; Tue, 27 Jul 2021 02:20:58 -0700 (PDT) Received: by mail-wm1-x32a.google.com with SMTP id b128so7088652wmb.4 for ; Tue, 27 Jul 2021 02:20:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=date:from:to:cc:subject:message-id:mail-followup-to:references :mime-version:content-disposition:in-reply-to; bh=Yvx7FUb+PO9K9tu4D9agXVqaQ0PZBo5xaT5yPpMKIms=; b=SIunivkJ3uBUWFL+MmqRwoRt2Ec13tI5ReuRrYPHU6v1ozJHB0RqmiXR2kJtHg7UkK kQHeIhOqy40affcu0iFYZjipx4Rj7mvXor6+msSm/jLTCD0shhRncWpbA8dQZkMdDKxG CY2f7wiJ4ZZW/66YmNtctsKo4S5yBfyNtbbac= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id :mail-followup-to:references:mime-version:content-disposition :in-reply-to; bh=Yvx7FUb+PO9K9tu4D9agXVqaQ0PZBo5xaT5yPpMKIms=; b=ih0wWU2iLWHUmmvo7NAKfae4wPXmDeX7GKrWOM4ywBB4H5ZD3zdptiUB0zE1fgnxTh BNyGinjrdjzUyIacigz7mt66Xs4vzTNFFsPYwS3asm4r1xJwrsQyfprk+G7KprQ93PyS II5TJXnfSOth5PhJsS+3r8FtnHftZoz6plIKIiqPU6pnuwEWD+Sj56CBzDgGo8OgUWkj zZlsmr6p1sE3kVYvTnvevFX4bhTHZBPNWXg1/WrqM9vdpYQklmJvWbWyqQL9JCUeLSJS 53L49rXN1H8G/BYResVloz14VQpJ+WWqrW+LYDAhFGy2MJWm0E0UIaJ8sxkMwy2KI/nV +5UQ== X-Gm-Message-State: AOAM532zQ2uVmgIhehgE5TNSm0SVtrC11u7XVpFxX+dLbMv5JTG4QZvx FD3+Yw9X/V0Cm/vv35z5N4b4Yw== X-Google-Smtp-Source: ABdhPJysqoczxFjCBoJFO3VIH1BODqUjcyDz8tshadU8bwCX8Ub+Bjigbsxk+srbu2FSB8xv5JCr8A== X-Received: by 2002:a05:600c:1c0d:: with SMTP id j13mr21332335wms.34.1627377657192; Tue, 27 Jul 2021 02:20:57 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id q19sm2002588wmq.38.2021.07.27.02.20.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 27 Jul 2021 02:20:56 -0700 (PDT) Date: Tue, 27 Jul 2021 11:20:54 +0200 From: Daniel Vetter To: Maxime Ripard Cc: Robert Foss , Andrzej Hajda , Daniel Vetter , David Airlie , Sam Ravnborg , Maarten Lankhorst , Thomas Zimmermann , Neil Armstrong , Jonas Karlman , Jernej Skrabec , Thierry Reding , Laurent Pinchart , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Subject: Re: [PATCH 04/10] drm/bridge: Document the probe issue with MIPI-DSI bridges Message-ID: Mail-Followup-To: Maxime Ripard , Robert Foss , Andrzej Hajda , Daniel Vetter , David Airlie , Sam Ravnborg , Maarten Lankhorst , Thomas Zimmermann , Neil Armstrong , Jonas Karlman , Jernej Skrabec , Thierry Reding , Laurent Pinchart , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org References: <20210720134525.563936-1-maxime@cerno.tech> <20210720134525.563936-5-maxime@cerno.tech> <20210726151657.c46qmkdvqfhlg6ox@gilmour> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210726151657.c46qmkdvqfhlg6ox@gilmour> X-Operating-System: Linux phenom 5.10.0-7-amd64 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 26, 2021 at 05:16:57PM +0200, Maxime Ripard wrote: > Hi Daniel, > > On Wed, Jul 21, 2021 at 02:05:01PM +0200, Daniel Vetter wrote: > > On Tue, Jul 20, 2021 at 03:45:19PM +0200, Maxime Ripard wrote: > > > Interactions between bridges, panels, MIPI-DSI host and the component > > > framework are not trivial and can lead to probing issues when > > > implementing a display driver. Let's document the various cases we need > > > too consider, and the solution to support all the cases. > > > > > > Signed-off-by: Maxime Ripard > > > > I still have this dream that eventually we resurrect a patch to add > > device_link to bridges/panels (ideally automatically), to help with some > > of the suspend/resume issues around here. > > > > Will this make things worse? > > > > I think it'd be really good to figure that out with some coding, since if > > we have incompatible solution to handle probe issues vs suspend/resume > > issues, we're screwed. > > > > Atm the duct-tape is to carefully move things around between suspend and > > suspend_early hooks (and resume and resume_late) and hope it all works ... > > My initial idea to fix this was indeed to use device links. I gave up > after a while since it doesn't look like there's a way to add a device > link before either the bridge or encoder probes. > > Indeed the OF-Graph representation is device-specific, so it can't be > generic, and if you need to probe to add that link, well, it's already > too late for the probe ordering :) But don't we still need the device_link for suspend/resume and module reload? All very annoying indeed anyway. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch 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=-8.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,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 EFD70C432BE for ; Tue, 27 Jul 2021 09:21:01 +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 AC40960F11 for ; Tue, 27 Jul 2021 09:21:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org AC40960F11 Authentication-Results: mail.kernel.org; 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Tue, 27 Jul 2021 02:20:56 -0700 (PDT) Date: Tue, 27 Jul 2021 11:20:54 +0200 From: Daniel Vetter To: Maxime Ripard Subject: Re: [PATCH 04/10] drm/bridge: Document the probe issue with MIPI-DSI bridges Message-ID: Mail-Followup-To: Maxime Ripard , Robert Foss , Andrzej Hajda , Daniel Vetter , David Airlie , Sam Ravnborg , Maarten Lankhorst , Thomas Zimmermann , Neil Armstrong , Jonas Karlman , Jernej Skrabec , Thierry Reding , Laurent Pinchart , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org References: <20210720134525.563936-1-maxime@cerno.tech> <20210720134525.563936-5-maxime@cerno.tech> <20210726151657.c46qmkdvqfhlg6ox@gilmour> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210726151657.c46qmkdvqfhlg6ox@gilmour> X-Operating-System: Linux phenom 5.10.0-7-amd64 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: Neil Armstrong , David Airlie , dri-devel@lists.freedesktop.org, Jonas Karlman , linux-kernel@vger.kernel.org, Robert Foss , Andrzej Hajda , Thierry Reding , Jernej Skrabec , Thomas Zimmermann , Daniel Vetter , Sam Ravnborg , Laurent Pinchart Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Mon, Jul 26, 2021 at 05:16:57PM +0200, Maxime Ripard wrote: > Hi Daniel, > > On Wed, Jul 21, 2021 at 02:05:01PM +0200, Daniel Vetter wrote: > > On Tue, Jul 20, 2021 at 03:45:19PM +0200, Maxime Ripard wrote: > > > Interactions between bridges, panels, MIPI-DSI host and the component > > > framework are not trivial and can lead to probing issues when > > > implementing a display driver. Let's document the various cases we need > > > too consider, and the solution to support all the cases. > > > > > > Signed-off-by: Maxime Ripard > > > > I still have this dream that eventually we resurrect a patch to add > > device_link to bridges/panels (ideally automatically), to help with some > > of the suspend/resume issues around here. > > > > Will this make things worse? > > > > I think it'd be really good to figure that out with some coding, since if > > we have incompatible solution to handle probe issues vs suspend/resume > > issues, we're screwed. > > > > Atm the duct-tape is to carefully move things around between suspend and > > suspend_early hooks (and resume and resume_late) and hope it all works ... > > My initial idea to fix this was indeed to use device links. I gave up > after a while since it doesn't look like there's a way to add a device > link before either the bridge or encoder probes. > > Indeed the OF-Graph representation is device-specific, so it can't be > generic, and if you need to probe to add that link, well, it's already > too late for the probe ordering :) But don't we still need the device_link for suspend/resume and module reload? All very annoying indeed anyway. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch