From 75096579c3ac39ddc2f8b0d9a8924eba31f4d920 Mon Sep 17 00:00:00 2001 From: Thierry Reding Date: Mon, 21 Jan 2013 11:08:54 +0100 Subject: 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 Cc: Arnd Bergmann Acked-by: Dmitry Torokhov Signed-off-by: Greg Kroah-Hartman --- lib/devres.c | 57 ++++++++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 44 insertions(+), 13 deletions(-) (limited to 'lib/devres.c') diff --git a/lib/devres.c b/lib/devres.c index 80b9c76d436a..9c76b3a9cc72 100644 --- a/lib/devres.c +++ b/lib/devres.c @@ -86,22 +86,24 @@ void devm_iounmap(struct device *dev, void __iomem *addr) 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(struct device *dev, 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(struct device *dev, 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(struct device *dev, 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 -- cgit v1.2.3 From f4a18312f46a6c6e0ba7b81776b01fc36edea9fc Mon Sep 17 00:00:00 2001 From: Thierry Reding Date: Tue, 22 Jan 2013 22:24:46 +0100 Subject: lib: devres: Fix build breakage The ERR_PTR() and IS_ERR() macros used by the devm_ioremap_resource() function are defined in the linux/err.h header. On ARM this seems to be pulled in by one of the other headers but the build fails at least on OpenRISC. Signed-off-by: Thierry Reding Reported-by: kbuild test robot Signed-off-by: Greg Kroah-Hartman --- lib/devres.c | 1 + 1 file changed, 1 insertion(+) (limited to 'lib/devres.c') diff --git a/lib/devres.c b/lib/devres.c index 9c76b3a9cc72..88ad75952a76 100644 --- a/lib/devres.c +++ b/lib/devres.c @@ -1,3 +1,4 @@ +#include #include #include #include -- cgit v1.2.3 From 9ed8a30f3471347c1b763bd062fa78ae80f18eae Mon Sep 17 00:00:00 2001 From: Jingoo Han Date: Wed, 27 Feb 2013 17:02:42 -0800 Subject: lib/devres.c: fix misplaced #endif A misplaced #endif causes link errors related to pcim_*() functions. This is because pcim_*() functions are related to CONFIG_PCI option, however these are not related to CONFIG_HAS_IOPORT option. Therefore, when CONFIG_PCI is enabled and CONFIG_HAS_IOPORT is not enabled, it makes link errors related to pcim_*() functions as below: drivers/ata/libata-sff.c:3233: undefined reference to `pcim_iomap_regions' drivers/ata/libata-sff.c:3238: undefined reference to `pcim_iomap_table' drivers/built-in.o: In function `ata_pci_sff_init_host': drivers/ata/libata-sff.c:2318: undefined reference to `pcim_iomap_regions' drivers/ata/libata-sff.c:2329: undefined reference to `pcim_iomap_table Signed-off-by: Jingoo Han Cc: Greg KH Cc: Tejun Heo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/devres.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib/devres.c') diff --git a/lib/devres.c b/lib/devres.c index 88ad75952a76..823533138fa0 100644 --- a/lib/devres.c +++ b/lib/devres.c @@ -227,6 +227,7 @@ void devm_ioport_unmap(struct device *dev, void __iomem *addr) devm_ioport_map_match, (void *)addr)); } EXPORT_SYMBOL(devm_ioport_unmap); +#endif /* CONFIG_HAS_IOPORT */ #ifdef CONFIG_PCI /* @@ -432,4 +433,3 @@ void pcim_iounmap_regions(struct pci_dev *pdev, int mask) } EXPORT_SYMBOL(pcim_iounmap_regions); #endif /* CONFIG_PCI */ -#endif /* CONFIG_HAS_IOPORT */ -- cgit v1.2.3