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; +}