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	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>
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					 2 changed files with 98 additions and 10 deletions
				
			
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			@ -177,17 +177,20 @@ struct platform_device *of_device_alloc(struct device_node *np,
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EXPORT_SYMBOL(of_device_alloc);
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/**
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 * of_platform_device_create - Alloc, initialize and register an of_device
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 * of_platform_device_create_pdata - Alloc, initialize and register an of_device
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 * @np: pointer to node to create device for
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 * @bus_id: name to assign device
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 * @platform_data: pointer to populate platform_data pointer with
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 * @parent: Linux device model parent device.
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 *
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 * Returns pointer to created platform device, or NULL if a device was not
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 * registered.  Unavailable devices will not get registered.
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 */
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struct platform_device *of_platform_device_create(struct device_node *np,
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					    const char *bus_id,
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					    struct device *parent)
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struct platform_device *of_platform_device_create_pdata(
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					struct device_node *np,
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					const char *bus_id,
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					void *platform_data,
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					struct device *parent)
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{
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	struct platform_device *dev;
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			@ -203,6 +206,7 @@ struct platform_device *of_platform_device_create(struct device_node *np,
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#endif
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	dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
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	dev->dev.bus = &platform_bus_type;
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	dev->dev.platform_data = platform_data;
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	/* We do not fill the DMA ops for platform devices by default.
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	 * This is currently the responsibility of the platform code
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			@ -216,6 +220,22 @@ struct platform_device *of_platform_device_create(struct device_node *np,
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	return dev;
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}
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/**
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 * of_platform_device_create - Alloc, initialize and register an of_device
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 * @np: pointer to node to create device for
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 * @bus_id: name to assign device
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 * @parent: Linux device model parent device.
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 *
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 * Returns pointer to created platform device, or NULL if a device was not
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 * registered.  Unavailable devices will not get registered.
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 */
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struct platform_device *of_platform_device_create(struct device_node *np,
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					    const char *bus_id,
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					    struct device *parent)
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{
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	return of_platform_device_create_pdata(np, bus_id, NULL, parent);
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}
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EXPORT_SYMBOL(of_platform_device_create);
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#ifdef CONFIG_ARM_AMBA
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			@ -283,6 +303,28 @@ static struct amba_device *of_amba_device_create(struct device_node *node,
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}
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#endif /* CONFIG_ARM_AMBA */
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/**
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 * of_devname_lookup() - Given a device node, lookup the preferred Linux name
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 */
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static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup,
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				 struct device_node *np)
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{
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	struct resource res;
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	if (lookup) {
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		for(; lookup->name != NULL; lookup++) {
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			if (!of_device_is_compatible(np, lookup->compatible))
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				continue;
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			if (of_address_to_resource(np, 0, &res))
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				continue;
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			if (res.start != lookup->phys_addr)
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				continue;
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			pr_debug("%s: devname=%s\n", np->full_name, lookup->name);
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			return lookup;
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		}
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	}
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	return NULL;
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}
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/**
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 * of_platform_bus_create() - Create a device for a node and its children.
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 * @bus: device node of the bus to instantiate
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			@ -295,10 +337,14 @@ static struct amba_device *of_amba_device_create(struct device_node *node,
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 */
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static int of_platform_bus_create(struct device_node *bus,
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				  const struct of_device_id *matches,
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				  const struct of_dev_auxdata *lookup,
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				  struct device *parent, bool strict)
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{
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	const struct of_dev_auxdata *auxdata;
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	struct device_node *child;
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	struct platform_device *dev;
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	const char *bus_id = NULL;
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	void *platform_data = NULL;
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	int rc = 0;
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	/* Make sure it has a compatible property */
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			@ -308,18 +354,24 @@ static int of_platform_bus_create(struct device_node *bus,
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		return 0;
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	}
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	auxdata = of_dev_lookup(lookup, bus);
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	if (auxdata) {
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		bus_id = auxdata->name;
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		platform_data = auxdata->platform_data;
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	}
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	if (of_device_is_compatible(bus, "arm,primecell")) {
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		of_amba_device_create(bus, NULL, NULL, parent);
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		of_amba_device_create(bus, bus_id, platform_data, parent);
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		return 0;
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	}
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	dev = of_platform_device_create(bus, NULL, parent);
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	dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
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	if (!dev || !of_match_node(matches, bus))
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		return 0;
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	for_each_child_of_node(bus, child) {
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		pr_debug("   create child: %s\n", child->full_name);
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		rc = of_platform_bus_create(child, matches, &dev->dev, strict);
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		rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
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		if (rc) {
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			of_node_put(child);
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			break;
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			@ -353,11 +405,11 @@ int of_platform_bus_probe(struct device_node *root,
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	/* Do a self check of bus type, if there's a match, create children */
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	if (of_match_node(matches, root)) {
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		rc = of_platform_bus_create(root, matches, parent, false);
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		rc = of_platform_bus_create(root, matches, NULL, parent, false);
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	} else for_each_child_of_node(root, child) {
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		if (!of_match_node(matches, child))
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			continue;
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		rc = of_platform_bus_create(child, matches, parent, false);
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		rc = of_platform_bus_create(child, matches, NULL, parent, false);
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		if (rc)
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			break;
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	}
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			@ -387,6 +439,7 @@ EXPORT_SYMBOL(of_platform_bus_probe);
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 */
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int of_platform_populate(struct device_node *root,
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			const struct of_device_id *matches,
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			const struct of_dev_auxdata *lookup,
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			struct device *parent)
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{
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	struct device_node *child;
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			@ -397,7 +450,7 @@ int of_platform_populate(struct device_node *root,
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		return -EINVAL;
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	for_each_child_of_node(root, child) {
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		rc = of_platform_bus_create(child, matches, parent, true);
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		rc = of_platform_bus_create(child, matches, lookup, parent, true);
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		if (rc)
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			break;
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	}
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			@ -19,6 +19,40 @@
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#include <linux/of_device.h>
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#include <linux/platform_device.h>
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/**
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 * struct of_dev_auxdata - lookup table entry for device names & platform_data
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 * @compatible: compatible value of node to match against node
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 * @phys_addr: Start address of registers to match against node
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 * @name: Name to assign for matching nodes
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 * @platform_data: platform_data to assign for matching nodes
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 *
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 * This lookup table allows the caller of of_platform_populate() to override
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 * the names of devices when creating devices from the device tree.  The table
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 * should be terminated with an empty entry.  It also allows the platform_data
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 * pointer to be set.
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 *
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 * The reason for this functionality is that some Linux infrastructure uses
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 * the device name to look up a specific device, but the Linux-specific names
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 * are not encoded into the device tree, so the kernel needs to provide specific
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 * values.
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 *
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 * Note: Using an auxdata lookup table should be considered a last resort when
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 * converting a platform to use the DT.  Normally the automatically generated
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 * device name will not matter, and drivers should obtain data from the device
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 * node instead of from an anonymouns platform_data pointer.
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 */
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struct of_dev_auxdata {
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	char *compatible;
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	resource_size_t phys_addr;
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	char *name;
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	void *platform_data;
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};
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/* Macro to simplify populating a lookup table */
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#define OF_DEV_AUXDATA(_compat,_phys,_name,_pdata) \
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	{ .compatible = _compat, .phys_addr = _phys, .name = _name, \
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	  .platform_data = _pdata }
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/**
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 * of_platform_driver - Legacy of-aware driver for platform devices.
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 *
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			@ -59,6 +93,7 @@ extern int of_platform_bus_probe(struct device_node *root,
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				 struct device *parent);
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extern int of_platform_populate(struct device_node *root,
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				const struct of_device_id *matches,
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				const struct of_dev_auxdata *lookup,
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				struct device *parent);
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#endif /* !CONFIG_SPARC */
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