[PATCH v8 1/7] of: Provide function to request and map memory
From: matthias.bgg@gmail.com (Matthias Brugger)
Date: 2014-06-11 12:34:32
Also in:
linux-devicetree, lkml
Subsystem:
open firmware and flattened device tree, the rest · Maintainers:
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> Acked-by: Grant Likely <redacted> --- drivers/of/address.c | 29 +++++++++++++++++++++++++++++ include/linux/of_address.h | 8 ++++++++ 2 files changed, 37 insertions(+)
diff --git a/drivers/of/address.c b/drivers/of/address.c
index 5edfcb0..d6b2900 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c@@ -702,6 +702,35 @@ 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 + */ +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 NULL; + + if (!request_mem_region(res.start, resource_size(&res), name)) + return NULL; + + mem = ioremap(res.start, resource_size(&res)); + if (!mem) + release_mem_region(res.start, resource_size(&res)); + + 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/of_address.h b/include/linux/of_address.h
index c13b878..0a13482 100644
--- a/include/linux/of_address.h
+++ b/include/linux/of_address.h@@ -109,6 +109,8 @@ 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 static inline int of_address_to_resource(struct device_node *dev, int index, struct resource *r)
@@ -120,6 +122,12 @@ 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 NULL; +} #endif #if defined(CONFIG_OF_ADDRESS) && defined(CONFIG_PCI)
--
1.7.9.5