Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751733AbdH3N7f (ORCPT ); Wed, 30 Aug 2017 09:59:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:57322 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751708AbdH3N7d (ORCPT ); Wed, 30 Aug 2017 09:59:33 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 933562199C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=helgaas@kernel.org Date: Wed, 30 Aug 2017 08:59:31 -0500 From: Bjorn Helgaas To: Thierry Reding Cc: Himanshu Jha , bhelgaas@google.com, jonathanh@nvidia.com, linux-tegra@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] PCI: tegra: Use PTR_ERR_OR_ZERO Message-ID: <20170830135931.GA18250@bhelgaas-glaptop.roam.corp.google.com> References: <1504013940-16304-1-git-send-email-himanshujha199640@gmail.com> <20170829135517.GA30733@ulmo> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170829135517.GA30733@ulmo> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1800 Lines: 48 On Tue, Aug 29, 2017 at 03:55:17PM +0200, Thierry Reding wrote: > On Tue, Aug 29, 2017 at 07:09:00PM +0530, Himanshu Jha wrote: > > Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR > > > > Signed-off-by: Himanshu Jha > > --- > > drivers/pci/host/pci-tegra.c | 5 +---- > > 1 file changed, 1 insertion(+), 4 deletions(-) > > > > diff --git a/drivers/pci/host/pci-tegra.c b/drivers/pci/host/pci-tegra.c > > index 9c40da5..90cda5b 100644 > > --- a/drivers/pci/host/pci-tegra.c > > +++ b/drivers/pci/host/pci-tegra.c > > @@ -1156,10 +1156,7 @@ static int tegra_pcie_resets_get(struct tegra_pcie *pcie) > > return PTR_ERR(pcie->afi_rst); > > > > pcie->pcie_xrst = devm_reset_control_get_exclusive(dev, "pcie_x"); > > - if (IS_ERR(pcie->pcie_xrst)) > > - return PTR_ERR(pcie->pcie_xrst); > > - > > - return 0; > > + return PTR_ERR_OR_ZERO(pcie->pcie_xrst); > > } > > I'm not a big fan of this construct because it's a pain to undo this if > ever we need to add code to this function. But since we do have scripts > that will flag this, I guess this would pop up every now and again. The > driver is unlikely to change in this part, too, so: Thanks for pointing this out. Do you know what the benefit of PTR_ERR_OR_ZERO() is? To me, it makes the following code harder to read because the error tests are no longer parallel: ... res->ahb_reset = devm_reset_control_get(dev, "ahb"); if (IS_ERR(res->ahb_reset)) return PTR_ERR(res->ahb_reset); res->por_reset = devm_reset_control_get(dev, "por"); if (IS_ERR(res->por_reset)) return PTR_ERR(res->por_reset); res->phy_reset = devm_reset_control_get(dev, "phy"); return PTR_ERR_OR_ZERO(res->phy_reset); So I'd be inclined to avoid it unless there's some significant benefit. Bjorn