[U-Boot] [PATCH v4 01/10] fdt: Add fdtdec functions to read byte array

Simon Glass
2012-04-17T19:01:28Z

From: Anton Staff <robotboy@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@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 7bae2f8..5140f4a 100644
--- a/include/fdtdec.h
+++ b/include/fdtdec.h
@@ -350,3 +350,35 @@ int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name,
* @return 0 if all ok or gpio was FDT_GPIO_NONE; -1 on error
*/
int fdtdec_setup_gpio(struct fdt_gpio_state *gpio);
+
+/*
+ * 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 2eb5b41..585dd6d 100644
--- a/lib/fdtdec.c
+++ b/lib/fdtdec.c
@@ -487,3 +487,27 @@ int fdtdec_setup_gpio(struct fdt_gpio_state *gpio)
return -1;
return 0;
}
+
+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