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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FAKE_REPLY_C,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 EE383C432C3 for ; Mon, 18 Nov 2019 14:24:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C38E52075E for ; Mon, 18 Nov 2019 14:24:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574087071; bh=MmJPqaX8nGIZrh4Dibpts0t0Dtr9+u4xiU8n8NZNzFk=; h=Date:From:To:Cc:Subject:In-Reply-To:List-ID:From; b=nBMFHL7QY0WZepZMYn8GXsdYOoV9NvPmrflBV9iP24VqZIjarcj1e85ZGG+31Qvg6 Q2yKkJtxyiDmMJxGHVHCaZN6puz7239u8/SzNigUeZsJ2DqUXG7DUhGqiCN1OpUesn xCqJ2GFbGaq6GXUgzULdR83y8Kozvf6M3hRfw9MA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726748AbfKROYb (ORCPT ); Mon, 18 Nov 2019 09:24:31 -0500 Received: from mail.kernel.org ([198.145.29.99]:42750 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726627AbfKROYb (ORCPT ); Mon, 18 Nov 2019 09:24:31 -0500 Received: from localhost (173-25-83-245.client.mchsi.com [173.25.83.245]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 243BD20692; Mon, 18 Nov 2019 14:24:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574087070; bh=MmJPqaX8nGIZrh4Dibpts0t0Dtr9+u4xiU8n8NZNzFk=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=0DBwzJUVz38PqTslrSrR99DBp0hhvJbtqNfpwBRRVJbr7NcsFqytNsE/o0HBgS1kJ m3e/oSIVp8rb5/IncQZO8v5/NjAcHywY71Ipbs2juUEgDOTwnwOZ5+drB+CyqiaBqw vN5Ch3XYMbzCfTXFa8f7oxKXQ5BFt8J/2GNyvQOo= Date: Mon, 18 Nov 2019 08:24:28 -0600 From: Bjorn Helgaas To: Mark Brown Cc: Robin Murphy , shawn.lin@rock-chips.com, lorenzo.pieralisi@arm.com, andrew.murray@arm.com, heiko@sntech.de, lgirdwood@gmail.com, linux-pci@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH 2/2] PCI: rockchip: Simplify optional regulator handling Message-ID: <20191118142428.GA27459@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191118115930.GC9761@sirena.org.uk> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Mon, Nov 18, 2019 at 11:59:30AM +0000, Mark Brown wrote: > On Sat, Nov 16, 2019 at 12:54:20PM +0000, Robin Murphy wrote: > > Null checks are both cheaper and more readable than having !IS_ERR() > > splattered everywhere. > > > - if (IS_ERR(rockchip->vpcie3v3)) > > + if (!rockchip->vpcie3v3) > > return; > > > > /* > > @@ -611,6 +611,7 @@ static int rockchip_pcie_parse_host_dt(struct rockchip_pcie *rockchip) > > if (PTR_ERR(rockchip->vpcie12v) != -ENODEV) > > return PTR_ERR(rockchip->vpcie12v); > > dev_info(dev, "no vpcie12v regulator found\n"); > > + rockchip->vpcie12v = NULL; > > According to the API NULL is a valid regulator. We don't currently > actually do this but it's storing up surprises if you treat it as > invalid. I don't know anything about the regulator API, but the fact that NULL can be a valid regulator is itself a little surprising :)