lkml.org 
[lkml]   [2012]   [Apr]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH V4 REPOST 1/5] dt: add property iteration helpers
Date
From: Stephen Warren <swarren@nvidia.com>

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>
---
v3: Moved code in base.c, defines/prototypes into of.h.
v2: Simplified the implementation per suggestion by Rob Herring.
Linus, this series is my previously posted V4 rebased on top of
next-20120404 plus all the changes from your for-next branch plus the
Makefile fix I posted last night. Note that I didn't see any conflicts
during the rebase; were you expecting me to?

Grant, you asked me to remind you about this patch after the merge window
closed. Note that it's a dependency of patch 5 in this series, so needs
to go in through the pinctrl tree, or both there and the DT tree.

drivers/of/base.c | 41 +++++++++++++++++++++++++++++++++++++++++
include/linux/of.h | 35 +++++++++++++++++++++++++++++++++++
2 files changed, 76 insertions(+), 0 deletions(-)
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 5806449..d9bfd49 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -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);
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 @@ 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 */

/**
--
1.7.0.4


\
 
 \ /
  Last update: 2012-04-04 17:31    [from the cache]
©2003-2011 Jasper Spaans