device property: Add fwnode_iomap()

This patch introduces a new helper routine - fwnode_iomap(), which
allows to map the memory mapped IO for a given device node.

This implementation does not cover the ACPI case and may be expanded
in the future. The main purpose here is to be able to develop resource
provider agnostic drivers.

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Anand Ashok Dumbre <anand.ashok.dumbre@xilinx.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20211203212358.31444-2-anand.ashok.dumbre@xilinx.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/base/property.c b/drivers/base/property.c
index f1f35b48ab8b9670faee7a071220d801bda09a3f..ed4470410030573748f24c82fc8c17d070e18074 100644 (file)
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -958,6 +958,22 @@ int fwnode_irq_get(const struct fwnode_handle *fwnode, unsigned int index)
 }
 EXPORT_SYMBOL(fwnode_irq_get);
 
+/**
+ * fwnode_iomap - Maps the memory mapped IO for a given fwnode
+ * @fwnode:    Pointer to the firmware node
+ * @index:     Index of the IO range
+ *
+ * Returns a pointer to the mapped memory.
+ */
+void __iomem *fwnode_iomap(struct fwnode_handle *fwnode, int index)
+{
+       if (IS_ENABLED(CONFIG_OF_ADDRESS) && is_of_node(fwnode))
+               return of_iomap(to_of_node(fwnode), index);
+
+       return NULL;
+}
+EXPORT_SYMBOL(fwnode_iomap);
+
 /**
  * fwnode_graph_get_next_endpoint - Get next endpoint firmware node
  * @fwnode: Pointer to the parent firmware node

diff --git a/include/linux/property.h b/include/linux/property.h
index 88fa726a76df7db5a7081343d87c3c3c79d7c445..6670d5a1ec2a3755f4f36a4b46a0226e7b38fb4e 100644 (file)
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -122,6 +122,8 @@ void fwnode_handle_put(struct fwnode_handle *fwnode);
 
 int fwnode_irq_get(const struct fwnode_handle *fwnode, unsigned int index);
 
+void __iomem *fwnode_iomap(struct fwnode_handle *fwnode, int index);
+
 unsigned int device_get_child_node_count(struct device *dev);
 
 static inline bool device_property_read_bool(struct device *dev,