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: Stephen Warren <swarren@nvidia.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/include/linux/of.h b/include/linux/of.h
index fa7fb1d..e3f942d 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -259,6 +259,37 @@
#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 @@
#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 */
/**