Merge tag 'firewire-fixes-6.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394

Pull firewire fixes from Takashi Sakamoto:
 "FireWire subsystem now supports the legacy layout of configuration
  ROM, while it appears that some of DV devices in the early 2000's have
  the legacy layout with a quirk. This includes some changes to handle
  the quirk"

* tag 'firewire-fixes-6.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394:
  firewire: core: search descriptor leaf just after vendor directory entry in root directory
  firewire: core: correct documentation of fw_csr_string() kernel API

1 files changed, 13 insertions, 5 deletions

diff --git a/drivers/firewire/core-device.c b/drivers/firewire/core-device.c
index 0547253d16fe..7d3346b3a2bf 100644
--- a/drivers/firewire/core-device.c
+++ b/drivers/firewire/core-device.c
@@ -118,10 +118,9 @@ static int textual_leaf_to_string(const u32 *block, char *buf, size_t size)
  * @buf:	where to put the string
  * @size:	size of @buf, in bytes
  *
- * The string is taken from a minimal ASCII text descriptor leaf after
- * the immediate entry with @key.  The string is zero-terminated.
- * An overlong string is silently truncated such that it and the
- * zero byte fit into @size.
+ * The string is taken from a minimal ASCII text descriptor leaf just after the entry with the
+ * @key. The string is zero-terminated. An overlong string is silently truncated such that it
+ * and the zero byte fit into @size.
  *
  * Returns strlen(buf) or a negative error code.
  */
@@ -368,8 +367,17 @@ static ssize_t show_text_leaf(struct device *dev,
 	for (i = 0; i < ARRAY_SIZE(directories) && !!directories[i]; ++i) {
 		int result = fw_csr_string(directories[i], attr->key, buf, bufsize);
 		// Detected.
-		if (result >= 0)
+		if (result >= 0) {
 			ret = result;
+		} else if (i == 0 && attr->key == CSR_VENDOR) {
+			// Sony DVMC-DA1 has configuration ROM such that the descriptor leaf entry
+			// in the root directory follows to the directory entry for vendor ID
+			// instead of the immediate value for vendor ID.
+			result = fw_csr_string(directories[i], CSR_DIRECTORY | attr->key, buf,
+					       bufsize);
+			if (result >= 0)
+				ret = result;
+		}
 	}
 
 	if (ret >= 0) {