[PATCH v10 1/7] of: Provide function to request and map memory
From: matthias.bgg@gmail.com (Matthias Brugger)
Date: 2014-07-07 15:13:56
Also in:
linux-devicetree, lkml
Subsystem:
library code, open firmware and flattened device tree, the rest · Maintainers:
Andrew Morton, Rob Herring, Saravana Kannan, Linus Torvalds
A call to of_iomap does not request the memory region. This patch adds the function of_io_request_and_map which requests the memory region before mapping it. Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com> Suggested-by: Thomas Gleixner <redacted> Suggested-by: Rob Herring <robh@kernel.org> --- drivers/of/address.c | 36 ++++++++++++++++++++++++++++++++++++ include/linux/io.h | 2 ++ include/linux/of_address.h | 11 +++++++++++ lib/devres.c | 2 -- 4 files changed, 49 insertions(+), 2 deletions(-)
diff --git a/drivers/of/address.c b/drivers/of/address.c
index 5edfcb0..e371825 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c@@ -702,6 +702,42 @@ void __iomem *of_iomap(struct device_node *np, int index) } EXPORT_SYMBOL(of_iomap); +/* + * of_io_request_and_map - Requests a resource and maps the memory mapped IO + * for a given device_node + * @device: the device whose io range will be mapped + * @index: index of the io range + * @name: name of the resource + * + * Returns a pointer to the requested and mapped memory or an ERR_PTR() encoded + * error code on failure. Usage example: + * + * base = of_io_request_and_map(node, 0, "foo"); + * if (IS_ERR(base)) + * return PTR_ERR(base); + */ +void __iomem *of_io_request_and_map(struct device_node *np, int index, + char *name) +{ + struct resource res; + void __iomem *mem; + + if (of_address_to_resource(np, index, &res)) + return IOMEM_ERR_PTR(-EINVAL); + + if (!request_mem_region(res.start, resource_size(&res), name)) + return IOMEM_ERR_PTR(-EBUSY); + + mem = ioremap(res.start, resource_size(&res)); + if (!mem) { + release_mem_region(res.start, resource_size(&res)); + return IOMEM_ERR_PTR(-ENOMEM); + } + + return mem; +} +EXPORT_SYMBOL(of_io_request_and_map); + /** * of_dma_get_range - Get DMA range info * @np: device node to get DMA range info
diff --git a/include/linux/io.h b/include/linux/io.h
index b76e6e5..d5fc9b8 100644
--- a/include/linux/io.h
+++ b/include/linux/io.h@@ -58,6 +58,8 @@ static inline void devm_ioport_unmap(struct device *dev, void __iomem *addr) } #endif +#define IOMEM_ERR_PTR(err) (__force void __iomem *)ERR_PTR(err) + void __iomem *devm_ioremap(struct device *dev, resource_size_t offset, unsigned long size); void __iomem *devm_ioremap_nocache(struct device *dev, resource_size_t offset,
diff --git a/include/linux/of_address.h b/include/linux/of_address.h
index c13b878..fb7b722 100644
--- a/include/linux/of_address.h
+++ b/include/linux/of_address.h@@ -109,7 +109,12 @@ static inline bool of_dma_is_coherent(struct device_node *np) extern int of_address_to_resource(struct device_node *dev, int index, struct resource *r); void __iomem *of_iomap(struct device_node *node, int index); +void __iomem *of_io_request_and_map(struct device_node *device, + int index, char *name); #else + +#include <linux/io.h> + static inline int of_address_to_resource(struct device_node *dev, int index, struct resource *r) {
@@ -120,6 +125,12 @@ static inline void __iomem *of_iomap(struct device_node *device, int index) { return NULL; } + +static inline void __iomem *of_io_request_and_map(struct device_node *device, + int index, char *name) +{ + return IOMEM_ERR_PTR(-EINVAL); +} #endif #if defined(CONFIG_OF_ADDRESS) && defined(CONFIG_PCI)
diff --git a/lib/devres.c b/lib/devres.c
index f562bf6..bb63248 100644
--- a/lib/devres.c
+++ b/lib/devres.c@@ -86,8 +86,6 @@ void devm_iounmap(struct device *dev, void __iomem *addr) } EXPORT_SYMBOL(devm_iounmap); -#define IOMEM_ERR_PTR(err) (__force void __iomem *)ERR_PTR(err) - /** * devm_ioremap_resource() - check, request region, and ioremap resource * @dev: generic device to handle the resource for
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1.7.9.5