diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/devres.c | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/lib/devres.c b/lib/devres.c index 5bec1120b392..faccf1a037d0 100644 --- a/lib/devres.c +++ b/lib/devres.c @@ -4,6 +4,7 @@ #include <linux/io.h> #include <linux/gfp.h> #include <linux/export.h> +#include <linux/of_address.h> enum devm_ioremap_type { DEVM_IOREMAP = 0, @@ -162,6 +163,41 @@ void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res) } EXPORT_SYMBOL(devm_ioremap_resource); +/* + * devm_of_iomap - Requests a resource and maps the memory mapped IO + * for a given device_node managed by a given device + * + * Checks that a resource is a valid memory region, requests the memory + * region and ioremaps it. All operations are managed and will be undone + * on driver detach of the device. + * + * This is to be used when a device requests/maps resources described + * by other device tree nodes (children or otherwise). + * + * @dev: The device "managing" the resource + * @node: The device-tree node where the resource resides + * @index: index of the MMIO range in the "reg" property + * @size: Returns the size of the resource (pass NULL if not needed) + * Returns a pointer to the requested and mapped memory or an ERR_PTR() encoded + * error code on failure. Usage example: + * + * base = devm_of_iomap(&pdev->dev, node, 0, NULL); + * if (IS_ERR(base)) + * return PTR_ERR(base); + */ +void __iomem *devm_of_iomap(struct device *dev, struct device_node *node, int index, + resource_size_t *size) +{ + struct resource res; + + if (of_address_to_resource(node, index, &res)) + return IOMEM_ERR_PTR(-EINVAL); + if (size) + *size = resource_size(&res); + return devm_ioremap_resource(dev, &res); +} +EXPORT_SYMBOL(devm_of_iomap); + #ifdef CONFIG_HAS_IOPORT_MAP /* * Generic iomap devres |