Commit c541adc6 authored by Stephen Warren's avatar Stephen Warren Committed by Linus Walleij
Browse files

dt: add property iteration helpers 



This patch adds macros of_property_for_each_u32() and
of_property_for_each_string(), which iterate over an array of values
within a device-tree property. Usage is for example:

struct property *prop;
const __be32 *p;
u32 u;
of_property_for_each_u32(np, "propname", prop, p, u)
	printk("U32 value: %x\n", u);

struct property *prop;
const char *s;
of_property_for_each_string(np, "propname", prop, s)
	printk("String value: %s\n", s);

Based on work by Rob Herring <robherring2@gmail.com>

Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: default avatarStephen Warren <swarren@nvidia.com>
Acked-by: default avatarRob Herring <rob.herring@calxeda.com>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent c05127c4

drivers/of/base.c

+41 −0
Original line number Diff line number Diff line
@@ -1260,3 +1260,44 @@ int of_alias_get_id(struct device_node *np, const char *stem) 
	return id;

}

EXPORT_SYMBOL_GPL(of_alias_get_id);



const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur,

			       u32 *pu)

{

	const void *curv = cur;



	if (!prop)

		return NULL;



	if (!cur) {

		curv = prop->value;

		goto out_val;

	}



	curv += sizeof(*cur);

	if (curv >= prop->value + prop->length)

		return NULL;



out_val:

	*pu = be32_to_cpup(curv);

	return curv;

}

EXPORT_SYMBOL_GPL(of_prop_next_u32);



const char *of_prop_next_string(struct property *prop, const char *cur)

{

	const void *curv = cur;



	if (!prop)

		return NULL;



	if (!cur)

		return prop->value;



	curv += strlen(cur) + 1;

	if (curv >= prop->value + prop->length)

		return NULL;



	return curv;

}

EXPORT_SYMBOL_GPL(of_prop_next_string);

include/linux/of.h

+35 −0
Original line number Diff line number Diff line
@@ -259,6 +259,37 @@ extern void of_detach_node(struct device_node *); 
#endif



#define of_match_ptr(_ptr)	(_ptr)



/*

 * struct property *prop;

 * const __be32 *p;

 * u32 u;

 *

 * of_property_for_each_u32(np, "propname", prop, p, u)

 *         printk("U32 value: %x\n", u);

 */

const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur,

			       u32 *pu);

#define of_property_for_each_u32(np, propname, prop, p, u)	\

	for (prop = of_find_property(np, propname, NULL),	\

		p = of_prop_next_u32(prop, NULL, &u);		\

		p;						\

		p = of_prop_next_u32(prop, p, &u))



/*

 * struct property *prop;

 * const char *s;

 *

 * of_property_for_each_string(np, "propname", prop, s)

 *         printk("String value: %s\n", s);

 */

const char *of_prop_next_string(struct property *prop, const char *cur);

#define of_property_for_each_string(np, propname, prop, s)	\

	for (prop = of_find_property(np, propname, NULL),	\

		s = of_prop_next_string(prop, NULL);		\

		s;						\

		s = of_prop_next_string(prop, s))



#else /* CONFIG_OF */



static inline bool of_have_populated_dt(void)
@@ -349,6 +380,10 @@ static inline int of_machine_is_compatible(const char *compat) 


#define of_match_ptr(_ptr)	NULL

#define of_match_node(_matches, _node)	NULL

#define of_property_for_each_u32(np, propname, prop, p, u) \

	while (0)

#define of_property_for_each_string(np, propname, prop, s) \

	while (0)

#endif /* CONFIG_OF */



/**

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