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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 6C8AAC43387 for ; Wed, 16 Jan 2019 14:22:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 412E9205C9 for ; Wed, 16 Jan 2019 14:22:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391266AbfAPOWm (ORCPT ); Wed, 16 Jan 2019 09:22:42 -0500 Received: from mail.bootlin.com ([62.4.15.54]:34804 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730649AbfAPOWm (ORCPT ); Wed, 16 Jan 2019 09:22:42 -0500 Received: by mail.bootlin.com (Postfix, from userid 110) id 8C8492078F; Wed, 16 Jan 2019 15:22:40 +0100 (CET) Received: from aptenodytes (aaubervilliers-681-1-37-87.w90-88.abo.wanadoo.fr [90.88.156.87]) by mail.bootlin.com (Postfix) with ESMTPSA id 5B1FD20763; Wed, 16 Jan 2019 15:22:40 +0100 (CET) Message-ID: Subject: Re: [PATCH] usb: chipidea: Grab the (legacy) USB PHY by phandle first From: Paul Kocialkowski To: Thomas Petazzoni Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Peter Chen , Greg Kroah-Hartman Date: Wed, 16 Jan 2019 15:22:40 +0100 In-Reply-To: <20190116144429.7df1d0c5@windsurf> References: <20190116101051.21202-1-paul.kocialkowski@bootlin.com> <20190116115350.3daa9b4f@windsurf> <554a5b4f463df6551846cfdc3b043d3f1d99381f.camel@bootlin.com> <20190116144429.7df1d0c5@windsurf> Organization: Bootlin Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.30.4 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Wed, 2019-01-16 at 14:44 +0100, Thomas Petazzoni wrote: > Well prior to your code, there was already a possibility for both > ci->phy and ci->usb_phy to be valid. I don't think it's really useful > to avoid the fallback when a generic PHY has already been found, it's > confusing. If really you want to clarify that, it should be: > > /* Let's first try to find a generic PHY */ > ci->phy = devm_phy_get(dev->parent, "usb-phy"); > if (IS_ERR(ci->phy)) { > /* Fall back to legacy USB PHY */ > ci->usb_phy = devm_usb_get_phy_by_phandle(dev->parent, "phys", 0); > if (IS_ERR(ci->usb_phy)) > ci->usb_phy = devm_usb_get_phy(dev->parent, USB_PHY_TYPE_USB2); > } > > With that, you would only have either ci->phy or ci->usb_phy be valid, > and never both. With your change, you can have ci->phy and ci->usb_phy > both be valid if the legacy USB PHY was found using > devm_usb_get_phy_by_phandle(), but not if we fell back to > devm_usb_get_phy(). Okay that makes sense, your suggestion is indeed more consistent with the existing behavior. I'll go with that in the next revision! Cheers, Paul -- Paul Kocialkowski, Bootlin Embedded Linux and kernel engineering https://bootlin.com