dt/platform: allow device name to be overridden

Some platform code has specific requirements on the naming of devices.
This patch allows callers of of_platform_populate() to provide a
device name lookup table.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 35 insertions, 0 deletions

diff --git a/include/linux/of_platform.h b/include/linux/of_platform.h
index 83902335117..5a6f458a4bb 100644
--- a/include/linux/of_platform.h
+++ b/include/linux/of_platform.h
@@ -20,6 +20,40 @@
 #include <linux/platform_device.h>
 
 /**
+ * struct of_dev_auxdata - lookup table entry for device names & platform_data
+ * @compatible: compatible value of node to match against node
+ * @phys_addr: Start address of registers to match against node
+ * @name: Name to assign for matching nodes
+ * @platform_data: platform_data to assign for matching nodes
+ *
+ * This lookup table allows the caller of of_platform_populate() to override
+ * the names of devices when creating devices from the device tree.  The table
+ * should be terminated with an empty entry.  It also allows the platform_data
+ * pointer to be set.
+ *
+ * The reason for this functionality is that some Linux infrastructure uses
+ * the device name to look up a specific device, but the Linux-specific names
+ * are not encoded into the device tree, so the kernel needs to provide specific
+ * values.
+ *
+ * Note: Using an auxdata lookup table should be considered a last resort when
+ * converting a platform to use the DT.  Normally the automatically generated
+ * device name will not matter, and drivers should obtain data from the device
+ * node instead of from an anonymouns platform_data pointer.
+ */
+struct of_dev_auxdata {
+	char *compatible;
+	resource_size_t phys_addr;
+	char *name;
+	void *platform_data;
+};
+
+/* Macro to simplify populating a lookup table */
+#define OF_DEV_AUXDATA(_compat,_phys,_name,_pdata) \
+	{ .compatible = _compat, .phys_addr = _phys, .name = _name, \
+	  .platform_data = _pdata }
+
+/**
  * of_platform_driver - Legacy of-aware driver for platform devices.
  *
  * An of_platform_driver driver is attached to a basic platform_device on
@@ -59,6 +93,7 @@ extern int of_platform_bus_probe(struct device_node *root,
 				 struct device *parent);
 extern int of_platform_populate(struct device_node *root,
 				const struct of_device_id *matches,
+				const struct of_dev_auxdata *lookup,
 				struct device *parent);
 #endif /* !CONFIG_SPARC */