pci_iomap.rar_V2

/* Implement the default iomap interfaces */ #include <linux/pci.h> #include <linux/io.h> #include <linux/export.h> #ifdef CONFIG_PCI /** * pci_iomap - create a virtual mapping cookie for a PCI BAR * @dev: PCI device that owns the BAR * @bar: BAR number * @maxlen: length of the memory to map * * Using this function you will get a __iomem address to your device BAR. * You can access it using ioread*() and iowrite*(). These functions hide * the details if this is a MMIO or PIO address space and will just do what * you expect from them in the correct way. * * @maxlen specifies the maximum length to map. If you want to get access to * the complete BAR without checking for its length first, pass %0 here. * */ void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen) { resource_size_t start = pci_resource_start(dev, bar); resource_size_t len = pci_resource_len(dev, bar); unsigned long flags = pci_resource_flags(dev, bar); if (!len || !start) return NULL; if (maxlen && len > maxlen) len = maxlen; if (flags & IORESOURCE_IO) return __pci_ioport_map(dev, start, len); if (flags & IORESOURCE_MEM) { if (flags & IORESOURCE_CACHEABLE) return ioremap(start, len); return ioremap_nocache(start, len); } /* What? */ return NULL; } EXPORT_SYMBOL(pci_iomap); #endif /* CONFIG_PCI */