lib: devres: add a helper function for ioremap_wc

Implement a resource managed writecombine ioremap function.

Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt
index 6d1e8eeb5990363c4441238ef305da3082b94b89..7fe7fd263aba138ca2e8fcc49484f76bc5142051 100644 (file)
--- a/Documentation/driver-model/devres.txt
+++ b/Documentation/driver-model/devres.txt
@@ -276,6 +276,7 @@ IOMAP
   devm_ioport_unmap()
   devm_ioremap()
   devm_ioremap_nocache()
+  devm_ioremap_wc()
   devm_ioremap_resource() : checks resource, requests memory region, ioremaps
   devm_iounmap()
   pcim_iomap()

diff --git a/include/linux/io.h b/include/linux/io.h
index fa02e55e5a2e1e2ea564829e1025a09d0722e4e2..42b33f03d1dfac0d823c942a133830801d138a32 100644 (file)
--- a/include/linux/io.h
+++ b/include/linux/io.h
@@ -64,6 +64,8 @@ void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
                           resource_size_t size);
 void __iomem *devm_ioremap_nocache(struct device *dev, resource_size_t offset,
                                   resource_size_t size);
+void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
+                                  resource_size_t size);
 void devm_iounmap(struct device *dev, void __iomem *addr);
 int check_signature(const volatile void __iomem *io_addr,
                        const unsigned char *signature, int length);

diff --git a/lib/devres.c b/lib/devres.c
index 0f1dd2e9d2c1e572386acb280695e76a2f58406e..fbe2aac522e67dc16708040128337eec946cd4ad 100644 (file)
--- a/lib/devres.c
+++ b/lib/devres.c
@@ -71,6 +71,34 @@ void __iomem *devm_ioremap_nocache(struct device *dev, resource_size_t offset,
 }
 EXPORT_SYMBOL(devm_ioremap_nocache);
 
+/**
+ * devm_ioremap_wc - Managed ioremap_wc()
+ * @dev: Generic device to remap IO address for
+ * @offset: BUS offset to map
+ * @size: Size of map
+ *
+ * Managed ioremap_wc().  Map is automatically unmapped on driver detach.
+ */
+void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
+                             resource_size_t size)
+{
+       void __iomem **ptr, *addr;
+
+       ptr = devres_alloc(devm_ioremap_release, sizeof(*ptr), GFP_KERNEL);
+       if (!ptr)
+               return NULL;
+
+       addr = ioremap_wc(offset, size);
+       if (addr) {
+               *ptr = addr;
+               devres_add(dev, ptr);
+       } else
+               devres_free(ptr);
+
+       return addr;
+}
+EXPORT_SYMBOL(devm_ioremap_wc);
+
 /**
  * devm_iounmap - Managed iounmap()
  * @dev: Generic device to unmap for