From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 619A9450EF for ; Mon, 18 Sep 2023 21:41:15 +0000 (UTC) Received: from out-228.mta1.migadu.com (out-228.mta1.migadu.com [IPv6:2001:41d0:203:375::e4]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C2A998E for ; Mon, 18 Sep 2023 14:41:12 -0700 (PDT) Date: Tue, 19 Sep 2023 07:40:58 +1000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=jookia.org; s=key1; t=1695073271; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=OKF5pL6j1FaLIvd2+LW2+OTS2g0SVXD9k2NzY4oj/+o=; b=eAJF0wJ6X+530eG3LxNkM63PN7qnRhh/PzY1ZTLxsu03jkiohE+49ByAC21ZDo4tPqDmtD Utn+P2HHAWUCvdC82d1DJZj0HWLlFu7mjzqztVYJuCuS5sYcUXfbGos0zKvYfKnhR7Z5qA qsZyeZ553i9kSJquTAxHnKvwFOqfq7ojHi4OXupJ5Ksrc+skSooeb1y5IKQ9gRlRxHPlBd Gq+2ryiO6nAieBGVdorZt/bQxqNXWh2iM5PgGV7fJTiz2Y6F3ZwH7oPw7iAwLBvrwWlW9+ mD/6OBOASGm4iSvTSmfKC45Yy3MNMGO/0KHhvpuKeDWRO5DGQMM1wyjRIxgOyA== X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: John Watts To: Paul Cercueil Cc: Jessica Zhang , dri-devel@lists.freedesktop.org, Neil Armstrong , Sam Ravnborg , David Airlie , Daniel Vetter , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Shawn Guo , Heiko Stuebner , Chris Morgan , Jagan Teki , Christophe Branchereau , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH v2 3/9] drm/panel: nv3052c: Sleep for 150ms after reset Message-ID: References: <20230918125853.2249187-1-contact@jookia.org> <20230918125853.2249187-4-contact@jookia.org> <7fc1ca68-ca7c-59b2-0b70-27bc34d83cee@quicinc.com> <4d2079d66249a7052acded0abf30169a4e95d151.camel@crapouillou.net> <0d6b0159552b10548391a9bd88449d12c13fdcd6.camel@crapouillou.net> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0d6b0159552b10548391a9bd88449d12c13fdcd6.camel@crapouillou.net> X-Migadu-Flow: FLOW_OUT X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_BLOCKED, SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net On Mon, Sep 18, 2023 at 11:34:51PM +0200, Paul Cercueil wrote: > The driver is guaranteed to always reset the panel in sleep-in mode - > as long as the panel was off when the driver started. > > What I'd suggest if you really need to support a case where the panel > was enabled by the bootloader, is to read the 0x0a register after > enabling the regulator to read the mode, and sleep 120ms if it was in > sleep-out mode. > > But that's only if it's a case that you can test with. I won't accept a > patch that makes sense on the surface if it addresses a corner case > that nobody ever tested for. > > For what I know, this patch just adds a huge delay to panel boot-up for > all existing users for no valid reason. > > > Cheers, > -Paul Thank you very much for this feedback. I am more than happy to throw these sleep patches in the trash and come back later with a proper solution when I have an actual hardware setup and use case to test on. John.