iomap: implement pcim_iounmap_regions()

Implement pcim_iounmap_regions() - the opposite of
pcim_iomap_regions().
Signed-off-by: Tejun heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

include/linux/pci.h

@@ -838,6 +838,7 @@ void __iomem * pcim_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen);
 void pcim_iounmap(struct pci_dev *pdev, void __iomem *addr);
 void __iomem * const * pcim_iomap_table(struct pci_dev *pdev);
 int pcim_iomap_regions(struct pci_dev *pdev, u16 mask, const char *name);
+void pcim_iounmap_regions(struct pci_dev *pdev, u16 mask);
 
 extern int pci_pci_problems;
 #define PCIPCI_FAIL		1	/* No PCI PCI DMA */

lib/devres.c

@@ -296,5 +296,31 @@ int pcim_iomap_regions(struct pci_dev *pdev, u16 mask, const char *name)
 	return rc;
 }
 EXPORT_SYMBOL(pcim_iomap_regions);
+
+/**
+ * pcim_iounmap_regions - Unmap and release PCI BARs
+ * @pdev: PCI device to map IO resources for
+ * @mask: Mask of BARs to unmap and release
+ *
+ * Unamp and release regions specified by @mask.
+ */
+void pcim_iounmap_regions(struct pci_dev *pdev, u16 mask)
+{
+	void __iomem * const *iomap;
+	int i;
+
+	iomap = pcim_iomap_table(pdev);
+	if (!iomap)
+		return;
+
+	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
+		if (!(mask & (1 << i)))
+			continue;
+
+		pcim_iounmap(pdev, iomap[i]);
+		pci_release_region(pdev, i);
+	}
+}
+EXPORT_SYMBOL(pcim_iounmap_regions);
 #endif
 #endif