From mboxrd@z Thu Jan 1 00:00:00 1970 From: catalin.marinas@arm.com (Catalin Marinas) Date: Wed, 20 May 2015 10:24:15 +0100 Subject: [V4 PATCH 3/6] pci: Generic function for setting up PCI device DMA coherency In-Reply-To: <3954735.qeaTp8qOcM@vostro.rjw.lan> References: <1431724994-21601-1-git-send-email-Suravee.Suthikulpanit@amd.com> <1431724994-21601-4-git-send-email-Suravee.Suthikulpanit@amd.com> <3954735.qeaTp8qOcM@vostro.rjw.lan> Message-ID: <20150520092415.GA25313@e104818-lin.cambridge.arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Sat, May 16, 2015 at 01:59:00AM +0200, Rafael J. Wysocki wrote: > On Friday, May 15, 2015 04:23:11 PM Suravee Suthikulpanit wrote: > > +/** > > + * pci_dma_configure - Setup DMA configuration > > + * @pci_dev: ptr to pci_dev struct of the PCI device > > + * > > + * Function to update PCI devices's DMA configuration using the same > > + * info from the OF node or ACPI node of host bridge's parent (if any). > > + */ > > +static void pci_dma_configure(struct pci_dev *pci_dev) > > +{ > > + struct device *dev = &pci_dev->dev; > > + struct device *bridge = pci_get_host_bridge_device(pci_dev); > > + struct device *host = bridge->parent; > > + struct acpi_device *adev; > > + > > + if (!host) > > + return; > > + > > + if (acpi_disabled) { > > + of_dma_configure(dev, host->of_node); > > I'd rather do > > if (IS_ENABLED(CONFIG_OF) && host->of_node) { > of_dma_configure(dev, host->of_node); Nitpick: do we need the CONFIG_OF check? If disabled, I don't think anyone would set host->of_node. -- Catalin