[PATCH v3 1/9] fdt: Add fdtdec functions to read byte array
Simon Glass
sjg at chromium.org
Tue Jan 17 17:11:14 EST 2012
From: Anton Staff <robotboy at chromium.org>
Sometimes we don't need a full cell for each value. This provides
a simple function to read a byte array, both with and without
copying it.
Signed-off-by: Simon Glass <sjg at chromium.org>
---
Changes in v2:
- Use correct name for get_prop_check_min_len() function
include/fdtdec.h | 32 ++++++++++++++++++++++++++++++++
lib/fdtdec.c | 24 ++++++++++++++++++++++++
2 files changed, 56 insertions(+), 0 deletions(-)
diff --git a/include/fdtdec.h b/include/fdtdec.h
index 64e2f88..9fd4e38 100644
--- a/include/fdtdec.h
+++ b/include/fdtdec.h
@@ -325,3 +325,35 @@ int fdtdec_setup_gpio(struct fdt_gpio_state *gpio);
* @return
*/
int fdtdec_decode_periph_id(const void *blob, int node);
+
+/*
+ * Look up a property in a node and return its contents in a byte
+ * array of given length. The property must have at least enough data for
+ * the array (count bytes). It may have more, but this will be ignored.
+ *
+ * @param blob FDT blob
+ * @param node node to examine
+ * @param prop_name name of property to find
+ * @param array array to fill with data
+ * @param count number of array elements
+ * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found,
+ * or -FDT_ERR_BADLAYOUT if not enough data
+ */
+int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
+ u8 *array, int count);
+
+/**
+ * Look up a property in a node and return a pointer to its contents as a
+ * byte array of given length. The property must have at least enough data
+ * for the array (count bytes). It may have more, but this will be ignored.
+ * The data is not copied.
+ *
+ * @param blob FDT blob
+ * @param node node to examine
+ * @param prop_name name of property to find
+ * @param count number of array elements
+ * @return pointer to byte array if found, or NULL if the property is not
+ * found or there is not enough data
+ */
+const u8 *fdtdec_locate_byte_array(const void *blob, int node,
+ const char *prop_name, int count);
diff --git a/lib/fdtdec.c b/lib/fdtdec.c
index db377c7..140310d 100644
--- a/lib/fdtdec.c
+++ b/lib/fdtdec.c
@@ -462,3 +462,27 @@ int fdtdec_decode_periph_id(const void *blob, int node)
return cell[1];
}
+
+int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
+ u8 *array, int count)
+{
+ const u8 *cell;
+ int err;
+
+ cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
+ if (!err)
+ memcpy(array, cell, count);
+ return err;
+}
+
+const u8 *fdtdec_locate_byte_array(const void *blob, int node,
+ const char *prop_name, int count)
+{
+ const u8 *cell;
+ int err;
+
+ cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
+ if (err)
+ return NULL;
+ return cell;
+}
--
1.7.7.3
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