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Commit efd342fb authored by Matthias Brugger's avatar Matthias Brugger Committed by Daniel Lezcano
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of: Provide a function to request and map memory 



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: default avatarMatthias Brugger <matthias.bgg@gmail.com>
Suggested-by: default avatarThomas Gleixner <tglx@linutronix.de>
Suggested-by: default avatarRob Herring <robh@kernel.org>
Acked-by: default avatarRob Herring <robh@kernel.org>
Signed-off-by: default avatarDaniel Lezcano <daniel.lezcano@linaro.org>
parent 7e139187

drivers/of/address.c

+36 −0
Original line number Diff line number Diff line
@@ -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

include/linux/io.h

+2 −0
Original line number Diff line number Diff line
@@ -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,

include/linux/of_address.h

+11 −0
Original line number Diff line number Diff line
@@ -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)

lib/devres.c

+0 −2
Original line number Diff line number Diff line
@@ -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