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=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 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 B452EC43603 for ; Tue, 17 Dec 2019 10:32:19 +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 5A2D920716 for ; Tue, 17 Dec 2019 10:32:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5A2D920716 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bootlin.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 5CCF66E97F; Tue, 17 Dec 2019 10:31:58 +0000 (UTC) Received: from relay1-d.mail.gandi.net (relay1-d.mail.gandi.net [217.70.183.193]) by gabe.freedesktop.org (Postfix) with ESMTPS id 74A4A6E4AE for ; Mon, 16 Dec 2019 10:53:37 +0000 (UTC) X-Originating-IP: 91.224.148.103 Received: from xps13 (unknown [91.224.148.103]) (Authenticated sender: miquel.raynal@bootlin.com) by relay1-d.mail.gandi.net (Postfix) with ESMTPSA id EB18C24000F; Mon, 16 Dec 2019 10:53:32 +0000 (UTC) Date: Mon, 16 Dec 2019 11:53:31 +0100 From: Miquel Raynal To: Sam Ravnborg Subject: Re: [PATCH] drm/panel: simple: Support reset GPIOs Message-ID: <20191216115331.5c6047f7@xps13> In-Reply-To: <20191214102354.GB2967@ravnborg.org> References: <20191213181325.26228-1-miquel.raynal@bootlin.com> <20191214102354.GB2967@ravnborg.org> Organization: Bootlin X-Mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 X-Mailman-Approved-At: Tue, 17 Dec 2019 10:31:56 +0000 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: Thomas Petazzoni , David Airlie , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Maxime Chevallier , Paul Kocialkowski , Thierry Reding Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" SGkgU2FtLAoKU2FtIFJhdm5ib3JnIDxzYW1AcmF2bmJvcmcub3JnPiB3cm90ZSBvbiBTYXQsIDE0 IERlYyAyMDE5IDExOjIzOjU0CiswMTAwOgoKPiBIaSBNaXF1ZWwuCj4gCj4gT24gRnJpLCBEZWMg MTMsIDIwMTkgYXQgMDc6MTM6MjVQTSArMDEwMCwgTWlxdWVsIFJheW5hbCB3cm90ZToKPiA+IFRo ZSBwYW5lbCBjb21tb24gYmluZGluZ3MgcHJvdmlkZSBhIGdwaW9zLXJlc2V0IHByb3BlcnR5IHdo aWNoIGlzCj4gPiBhY3RpdmUgbG93IGJ5IGRlZmF1bHQuIExldCdzIHN1cHBvcnQgaXQgaW4gdGhl IHNpbXBsZSBkcml2ZXIuCj4gPiAKPiA+IERlLWFzc2VydGluZyB0aGUgcmVzZXQgcGluIGltcGxp ZXMgYSBwaHlzaWNhbCBoaWdoLCB3aGljaCBpbiB0dXJucyBpcwo+ID4gYSBsb2dpYyBsb3cuCj4g PiAKPiA+IFNpZ25lZC1vZmYtYnk6IE1pcXVlbCBSYXluYWwgPG1pcXVlbC5yYXluYWxAYm9vdGxp bi5jb20+ICAKPiAKPiBDb2RlIGxvb2tzIGZpbmUgLSBidXQgSSBmYWlsIHRvIHNlZSB3aHkgc2lt cGxlIHBhbmVscyB3b3VsZCByZXF1aXJlIGEKPiByZXNldCBwaW4uCj4gCj4gRG8geW91IGhhdmUg YW55IHNpbXBsZSBwYW5lbHMgdGhhdCByZXF1aXJlcyB0aGlzLCBvciBkaWQgeW91IGFkZCBpdAo+ IGJlY2F1c2UgeW91IHNhdyBpdCBpbiB0aGUgcGFuZWwtY29tbW9uLnlhbWwgZmlsZT8KCk15IGhh cmR3YXJlIGlzOgoKTFZEUyBJUCA8LS0tLS0tLS0tLT4gTFZEUyB0byBSR0IgYnJpZGdlIDwtLS0t LS0tLS0tLS0+IFBhbmVsCgpXaGlsZSB0aGVyZSBpcyBhIHNpbXBsZSAiUkdCIHRvIExWRFMiIGJy aWRnZSBkcml2ZXIsIHRoZXJlIGlzIG5vbmUKZG9pbmcgdGhlIHdvcmsgdGhlIG90aGVyIHdheSBh cm91bmQuIEluIG15IGNhc2UsIHRoZSBicmlkZ2UgaGFzIGEgcmVzZXQKcGluLgoKQXMgdW50aWwg bm93IHRoZXJlIGlzIG5vIHdheSB0byByZXByZXNlbnQgdGhlICJMVkRTIHRvIFJHQiIgYnJpZGdl IGFuZApiZWNhdXNlIHRoZSBiaW5kaW5ncyBhbHJlYWR5IGRvY3VtZW50IHN1Y2ggcmVzZXQgcGlu LCBJIGRlY2lkZWQgdG8gYWRkCnN1cHBvcnQgZm9yIGl0IGluIHRoZSBzaW1wbGUgcGFuZWwgZHJp dmVyLgoKVGhhbmtzLApNaXF1w6hsCl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fCmRyaS1kZXZlbCBtYWlsaW5nIGxpc3QKZHJpLWRldmVsQGxpc3RzLmZyZWVk ZXNrdG9wLm9yZwpodHRwczovL2xpc3RzLmZyZWVkZXNrdG9wLm9yZy9tYWlsbWFuL2xpc3RpbmZv L2RyaS1kZXZlbAo= 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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 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 98C8CC2D0BF for ; Mon, 16 Dec 2019 10:53:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6AED420684 for ; Mon, 16 Dec 2019 10:53:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727534AbfLPKxg convert rfc822-to-8bit (ORCPT ); Mon, 16 Dec 2019 05:53:36 -0500 Received: from relay1-d.mail.gandi.net ([217.70.183.193]:38131 "EHLO relay1-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727403AbfLPKxg (ORCPT ); Mon, 16 Dec 2019 05:53:36 -0500 X-Originating-IP: 91.224.148.103 Received: from xps13 (unknown [91.224.148.103]) (Authenticated sender: miquel.raynal@bootlin.com) by relay1-d.mail.gandi.net (Postfix) with ESMTPSA id EB18C24000F; Mon, 16 Dec 2019 10:53:32 +0000 (UTC) Date: Mon, 16 Dec 2019 11:53:31 +0100 From: Miquel Raynal To: Sam Ravnborg Cc: Thierry Reding , David Airlie , Daniel Vetter , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Paul Kocialkowski , Maxime Chevallier , Thomas Petazzoni Subject: Re: [PATCH] drm/panel: simple: Support reset GPIOs Message-ID: <20191216115331.5c6047f7@xps13> In-Reply-To: <20191214102354.GB2967@ravnborg.org> References: <20191213181325.26228-1-miquel.raynal@bootlin.com> <20191214102354.GB2967@ravnborg.org> Organization: Bootlin X-Mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Sam, Sam Ravnborg wrote on Sat, 14 Dec 2019 11:23:54 +0100: > Hi Miquel. > > On Fri, Dec 13, 2019 at 07:13:25PM +0100, Miquel Raynal wrote: > > The panel common bindings provide a gpios-reset property which is > > active low by default. Let's support it in the simple driver. > > > > De-asserting the reset pin implies a physical high, which in turns is > > a logic low. > > > > Signed-off-by: Miquel Raynal > > Code looks fine - but I fail to see why simple panels would require a > reset pin. > > Do you have any simple panels that requires this, or did you add it > because you saw it in the panel-common.yaml file? My hardware is: LVDS IP <----------> LVDS to RGB bridge <------------> Panel While there is a simple "RGB to LVDS" bridge driver, there is none doing the work the other way around. In my case, the bridge has a reset pin. As until now there is no way to represent the "LVDS to RGB" bridge and because the bindings already document such reset pin, I decided to add support for it in the simple panel driver. Thanks, Miquèl