From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754051AbdLDQUU (ORCPT ); Mon, 4 Dec 2017 11:20:20 -0500 Received: from mail1.skidata.com ([91.230.2.99]:29640 "EHLO mail1.skidata.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753115AbdLDQUQ (ORCPT ); Mon, 4 Dec 2017 11:20:16 -0500 X-IronPort-AV: E=Sophos;i="5.45,359,1508796000"; d="scan'208";a="7448880" Subject: Re: [PATCH v4.1] phylib: Add device reset GPIO support To: Geert Uytterhoeven , "David S . Miller" , Andrew Lunn , Florian Fainelli , Simon Horman , Magnus Damm CC: Sergei Shtylyov , Rob Herring , Mark Rutland , Nicolas Ferre , , , , References: <1512383692-14009-2-git-send-email-geert+renesas@glider.be> <1512390905-28094-1-git-send-email-geert+renesas@glider.be> From: Richard Leitner Message-ID: Date: Mon, 4 Dec 2017 17:20:13 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.5.0 MIME-Version: 1.0 In-Reply-To: <1512390905-28094-1-git-send-email-geert+renesas@glider.be> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 8bit X-Originating-IP: [172.16.60.30] X-ClientProxiedBy: sdex1srv.skidata.net (172.16.10.92) To sdex1srv.skidata.net (172.16.10.92) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/04/2017 01:35 PM, Geert Uytterhoeven wrote: > From: Sergei Shtylyov > > The PHY devices sometimes do have their reset signal (maybe even power > supply?) tied to some GPIO and sometimes it also does happen that a boot > loader does not leave it deasserted. So far this issue has been attacked > from (as I believe) a wrong angle: by teaching the MAC driver to manipulate > the GPIO in question; that solution, when applied to the device trees, led > to adding the PHY reset GPIO properties to the MAC device node, with one > exception: Cadence MACB driver which could handle the "reset-gpios" prop > in a PHY device subnode. I believe that the correct approach is to teach > the 'phylib' to get the MDIO device reset GPIO from the device tree node > corresponding to this device -- which this patch is doing... > > Note that I had to modify the AT803x PHY driver as it would stop working > otherwise -- it made use of the reset GPIO for its own purposes... > > Signed-off-by: Sergei Shtylyov > Acked-by: Rob Herring > [geert: Propagate actual errors from fwnode_get_named_gpiod()] > [geert: Avoid destroying initial setup] > [geert: Consolidate GPIO descriptor acquiring code] > Signed-off-by: Geert Uytterhoeven > --- Successfully tested this patch on a i.MX6SOLO based board containing a LAN8710 PHY: Tested-by: Richard Leitner