diff options
Diffstat (limited to 'drivers/firewire')
-rw-r--r-- | drivers/firewire/core-device.c | 26 |
1 files changed, 16 insertions, 10 deletions
diff --git a/drivers/firewire/core-device.c b/drivers/firewire/core-device.c index a39e4344cd5..5d5c6a68983 100644 --- a/drivers/firewire/core-device.c +++ b/drivers/firewire/core-device.c @@ -69,19 +69,22 @@ static u32 *search_leaf(u32 *directory, int search_key) if (last_key == search_key && key == (CSR_DESCRIPTOR | CSR_LEAF)) return ci.p - 1 + value; + last_key = key; } + return NULL; } static int textual_leaf_to_string(u32 *block, char *buf, size_t size) { - unsigned int quadlets, length; + unsigned int quadlets, i; + char c; if (!size || !buf) return -EINVAL; - quadlets = min(block[0] >> 16, 256u); + quadlets = min(block[0] >> 16, 256U); if (quadlets < 2) return -ENODATA; @@ -91,31 +94,34 @@ static int textual_leaf_to_string(u32 *block, char *buf, size_t size) block += 3; quadlets -= 2; - for (length = 0; length < quadlets * 4 && length + 1 < size; length++) { - char c = block[length / 4] >> (24 - 8 * (length % 4)); + for (i = 0; i < quadlets * 4 && i < size - 1; i++) { + c = block[i / 4] >> (24 - 8 * (i % 4)); if (c == '\0') break; - buf[length] = c; + buf[i] = c; } - buf[length] = '\0'; - return length; + buf[i] = '\0'; + + return i; } /** * fw_csr_string - reads a string from the configuration ROM - * @directory: device or unit directory; - * fw_device->config_rom+5 or fw_unit->directory + * @directory: e.g. root directory or unit directory * @key: the key of the preceding directory entry * @buf: where to put the string * @size: size of @buf, in bytes * - * Returns string length (>= 0) or error code (< 0). + * The string is taken from a minimal ASCII text descriptor leaf after + * the immediate entry with @key. The string is zero-terminated. + * Returns strlen(buf) or a negative error code. */ int fw_csr_string(u32 *directory, int key, char *buf, size_t size) { u32 *leaf = search_leaf(directory, key); if (!leaf) return -ENOENT; + return textual_leaf_to_string(leaf, buf, size); } EXPORT_SYMBOL(fw_csr_string); |