--- /dev/null
+From 75096579c3ac39ddc2f8b0d9a8924eba31f4d920 Mon Sep 17 00:00:00 2001
+From: Thierry Reding <thierry.reding@avionic-design.de>
+Date: Mon, 21 Jan 2013 11:08:54 +0100
+Subject: [PATCH] lib: devres: Introduce devm_ioremap_resource()
+
+The devm_request_and_ioremap() function is very useful and helps avoid a
+whole lot of boilerplate. However, one issue that keeps popping up is
+its lack of a specific error code to determine which of the steps that
+it performs failed. Furthermore, while the function gives an example and
+suggests what error code to return on failure, a wide variety of error
+codes are used throughout the tree.
+
+In an attempt to fix these problems, this patch adds a new function that
+drivers can transition to. The devm_ioremap_resource() returns a pointer
+to the remapped I/O memory on success or an ERR_PTR() encoded error code
+on failure. Callers can check for failure using IS_ERR() and determine
+its cause by extracting the error code using PTR_ERR().
+
+devm_request_and_ioremap() is implemented as a wrapper around the new
+API and return NULL on failure as before. This ensures that backwards
+compatibility is maintained until all users have been converted to the
+new API, at which point the old devm_request_and_ioremap() function
+should be removed.
+
+A semantic patch is included which can be used to convert from the old
+devm_request_and_ioremap() API to the new devm_ioremap_resource() API.
+Some non-trivial cases may require manual intervention, though.
+
+Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
+Cc: Arnd Bergmann <arnd@arndb.de>
+Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ Documentation/driver-model/devres.txt | 3 +-
+ include/linux/device.h | 1 +
+ lib/devres.c | 57 ++++++++++---
+ scripts/coccinelle/api/devm_ioremap_resource.cocci | 90 ++++++++++++++++++++
+ 4 files changed, 137 insertions(+), 14 deletions(-)
+ create mode 100644 scripts/coccinelle/api/devm_ioremap_resource.cocci
+
+--- a/Documentation/driver-model/devres.txt
++++ b/Documentation/driver-model/devres.txt
+@@ -266,7 +266,8 @@ IOMAP
+ devm_ioremap()
+ devm_ioremap_nocache()
+ devm_iounmap()
+- devm_request_and_ioremap() : checks resource, requests region, ioremaps
++ devm_ioremap_resource() : checks resource, requests memory region, ioremaps
++ devm_request_and_ioremap() : obsoleted by devm_ioremap_resource()
+ pcim_iomap()
+ pcim_iounmap()
+ pcim_iomap_table() : array of mapped addresses indexed by BAR
+--- a/include/linux/device.h
++++ b/include/linux/device.h
+@@ -573,6 +573,7 @@ extern int devres_release_group(struct d
+ extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
+ extern void devm_kfree(struct device *dev, void *p);
+
++void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);
+ void __iomem *devm_request_and_ioremap(struct device *dev,
+ struct resource *res);
+
+--- a/lib/devres.c
++++ b/lib/devres.c
+@@ -86,22 +86,24 @@ void devm_iounmap(struct device *dev, vo
+ EXPORT_SYMBOL(devm_iounmap);
+
+ /**
+- * devm_request_and_ioremap() - Check, request region, and ioremap resource
+- * @dev: Generic device to handle the resource for
++ * devm_ioremap_resource() - check, request region, and ioremap resource
++ * @dev: generic device to handle the resource for
+ * @res: resource to be handled
+ *
+- * Takes all necessary steps to ioremap a mem resource. Uses managed device, so
+- * everything is undone on driver detach. Checks arguments, so you can feed
+- * it the result from e.g. platform_get_resource() directly. Returns the
+- * remapped pointer or NULL on error. Usage example:
++ * Checks that a resource is a valid memory region, requests the memory region
++ * and ioremaps it either as cacheable or as non-cacheable memory depending on
++ * the resource's flags. All operations are managed and will be undone on
++ * driver detach.
++ *
++ * Returns a pointer to the remapped memory or an ERR_PTR() encoded error code
++ * on failure. Usage example:
+ *
+ * res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+- * base = devm_request_and_ioremap(&pdev->dev, res);
+- * if (!base)
+- * return -EADDRNOTAVAIL;
++ * base = devm_ioremap_resource(&pdev->dev, res);
++ * if (IS_ERR(base))
++ * return PTR_ERR(base);
+ */
+-void __iomem *devm_request_and_ioremap(struct device *dev,
+- struct resource *res)
++void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res)
+ {
+ resource_size_t size;
+ const char *name;
+@@ -111,7 +113,7 @@ void __iomem *devm_request_and_ioremap(s
+
+ if (!res || resource_type(res) != IORESOURCE_MEM) {
+ dev_err(dev, "invalid resource\n");
+- return NULL;
++ return ERR_PTR(-EINVAL);
+ }
+
+ size = resource_size(res);
+@@ -119,7 +121,7 @@ void __iomem *devm_request_and_ioremap(s
+
+ if (!devm_request_mem_region(dev, res->start, size, name)) {
+ dev_err(dev, "can't request region for resource %pR\n", res);
+- return NULL;
++ return ERR_PTR(-EBUSY);
+ }
+
+ if (res->flags & IORESOURCE_CACHEABLE)
+@@ -130,10 +132,39 @@ void __iomem *devm_request_and_ioremap(s
+ if (!dest_ptr) {
+ dev_err(dev, "ioremap failed for resource %pR\n", res);
+ devm_release_mem_region(dev, res->start, size);
++ dest_ptr = ERR_PTR(-ENOMEM);
+ }
+
+ return dest_ptr;
+ }
++EXPORT_SYMBOL(devm_ioremap_resource);
++
++/**
++ * devm_request_and_ioremap() - Check, request region, and ioremap resource
++ * @dev: Generic device to handle the resource for
++ * @res: resource to be handled
++ *
++ * Takes all necessary steps to ioremap a mem resource. Uses managed device, so
++ * everything is undone on driver detach. Checks arguments, so you can feed
++ * it the result from e.g. platform_get_resource() directly. Returns the
++ * remapped pointer or NULL on error. Usage example:
++ *
++ * res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
++ * base = devm_request_and_ioremap(&pdev->dev, res);
++ * if (!base)
++ * return -EADDRNOTAVAIL;
++ */
++void __iomem *devm_request_and_ioremap(struct device *device,
++ struct resource *res)
++{
++ void __iomem *dest_ptr;
++
++ dest_ptr = devm_ioremap_resource(device, res);
++ if (IS_ERR(dest_ptr))
++ return NULL;
++
++ return dest_ptr;
++}
+ EXPORT_SYMBOL(devm_request_and_ioremap);
+
+ #ifdef CONFIG_HAS_IOPORT
+--- /dev/null
++++ b/scripts/coccinelle/api/devm_ioremap_resource.cocci
+@@ -0,0 +1,90 @@
++virtual patch
++virtual report
++
++@depends on patch@
++expression base, dev, res;
++@@
++
++-base = devm_request_and_ioremap(dev, res);
+++base = devm_ioremap_resource(dev, res);
++ ...
++ if (
++-base == NULL
+++IS_ERR(base)
++ || ...) {
++<...
++- return ...;
+++ return PTR_ERR(base);
++...>
++ }
++
++@depends on patch@
++expression e, E, ret;
++identifier l;
++@@
++
++ e = devm_ioremap_resource(...);
++ ...
++ if (IS_ERR(e) || ...) {
++ ... when any
++- ret = E;
+++ ret = PTR_ERR(e);
++ ...
++(
++ return ret;
++|
++ goto l;
++)
++ }
++
++@depends on patch@
++expression e;
++@@
++
++ e = devm_ioremap_resource(...);
++ ...
++ if (IS_ERR(e) || ...) {
++ ...
++- \(dev_dbg\|dev_err\|pr_debug\|pr_err\|DRM_ERROR\)(...);
++ ...
++ }
++
++@depends on patch@
++expression e;
++identifier l;
++@@
++
++ e = devm_ioremap_resource(...);
++ ...
++ if (IS_ERR(e) || ...)
++-{
++(
++ return ...;
++|
++ goto l;
++)
++-}
++
++@r depends on report@
++expression e;
++identifier l;
++position p1;
++@@
++
++*e = devm_request_and_ioremap@p1(...);
++ ...
++ if (e == NULL || ...) {
++ ...
++(
++ return ...;
++|
++ goto l;
++)
++ }
++
++@script:python depends on r@
++p1 << r.p1;
++@@
++
++msg = "ERROR: deprecated devm_request_and_ioremap() API used on line %s" % (p1[0].line)
++coccilib.report.print_report(p1[0], msg)
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