lkml.org 
[lkml]   [2012]   [Mar]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH V2 1/6] dt: add property iteration helpers
Date
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>

Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
---
v2: Simplified the implementation per suggestion by Rob Herring.
---
include/linux/of_iter_prop.h | 101 ++++++++++++++++++++++++++++++++++++++++++
1 files changed, 101 insertions(+), 0 deletions(-)
create mode 100644 include/linux/of_iter_prop.h
diff --git a/include/linux/of_iter_prop.h b/include/linux/of_iter_prop.h
new file mode 100644
index 0000000..e3df23c
--- /dev/null
+++ b/include/linux/of_iter_prop.h
@@ -0,0 +1,101 @@
+/*
+ * Copyright (c) 2011-2012 NVIDIA CORPORATION. All rights reserved.
+ *
+ * Iterate over properties that store arrays.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __OF_ITER_PROP_H__
+#define __OF_ITER_PROP_H__
+
+#include <linux/of.h>
+
+#ifdef CONFIG_OF
+static inline 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;
+}
+
+/*
+ * struct property *prop;
+ * const __be32 *p;
+ * u32 u;
+ *
+ * of_property_for_each_u32(np, "propname", prop, p, u)
+ * printk("U32 value: %x\n", u);
+ */
+#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))
+
+static inline 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;
+}
+
+/*
+ * struct property *prop;
+ * const char *s;
+ *
+ * of_property_for_each_string(np, "propname", prop, s)
+ * printk("String value: %s\n", s);
+ */
+#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
+
+#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 */
+
+#endif /* __OF_ITER_PROP_H__ */
--
1.7.0.4


\
 
 \ /
  Last update: 2012-03-20 18:47    [from the cache]
©2003-2011 Jasper Spaans