From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [PATCH 5/5] usb: add pxa1928 ehci support Date: Fri, 15 May 2015 11:32:12 +0200 Message-ID: <4475721.5hJuZmGMm7@wuerfel> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Alan Stern Cc: Rob Herring , Greg Kroah-Hartman , Kishon Vijay Abraham I , linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-usb@vger.kernel.org List-Id: devicetree@vger.kernel.org On Thursday 14 May 2015 11:55:36 Alan Stern wrote: > > > + hcd->phy = devm_of_phy_get(&pdev->dev, pdev->dev.of_node, NULL); > > + if (IS_ERR_OR_NULL(hcd->phy)) { > > + retval = PTR_ERR(hcd->phy); > > + if (retval != -EPROBE_DEFER && retval != -ENODEV) > > + dev_err(&pdev->dev, "failed to get the phy\n"); > > + else > > + return -EPROBE_DEFER; > > + goto err_put_hcd; > > + } > > Please straighten out this convoluted logic. It should go like this: > > hcd->phy = devm_of_phy_get(&pdev->dev, pdev->dev.of_node, NULL); > if (IS_ERR_OR_NULL(hcd->phy)) { > retval = PTR_ERR(hcd->phy); > if (retval == -EPROBE_DEFER || retval == -ENODEV) > return -EPROBE_DEFER; > dev_err(&pdev->dev, "failed to get the phy\n"); > goto err_put_hcd; > } > IS_ERR_OR_NULL is almost always wrong. Kernel interfaces that can return an error pointer should never return a NULL pointer, and I'm pretty sure that is also the case for the phy subsystem (or else it should be fixed). In some cases, we have interfaces that return NULL pointers or error pointers, but those are designed to treat NULL as success. Arnd