firewire: also use vendor ID in root directory for driver matches

Due to AV/C protocol extensions, FireDTV devices need a vendor-specific
driver.  But their configuration ROM features a vendor ID only in the
root directory, not in the unit directory.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

1 files changed, 16 insertions, 6 deletions

diff --git a/drivers/firewire/fw-device.c b/drivers/firewire/fw-device.c
index 47b5b422616b..7d2f6135e009 100644
--- a/drivers/firewire/fw-device.c
+++ b/drivers/firewire/fw-device.c
@@ -58,7 +58,7 @@ EXPORT_SYMBOL(fw_csr_iterator_next);
 
 static int is_fw_unit(struct device *dev);
 
-static int match_unit_directory(u32 *directory,
+static int match_unit_directory(u32 *directory, u32 match_flags,
                                 const struct ieee1394_device_id *id)
 {
         struct fw_csr_iterator ci;
@@ -77,21 +77,31 @@ static int match_unit_directory(u32 *directory,
                         match |= IEEE1394_MATCH_VERSION;
         }
 
-        return (match & id->match_flags) == id->match_flags;
+        return (match & match_flags) == match_flags;
 }
 
 static int fw_unit_match(struct device *dev, struct device_driver *drv)
 {
         struct fw_unit *unit = fw_unit(dev);
-        struct fw_driver *driver = fw_driver(drv);
-        int i;
+        struct fw_device *device;
+        const struct ieee1394_device_id *id;
 
         /* We only allow binding to fw_units. */
         if (!is_fw_unit(dev))
                 return 0;
 
-        for (i = 0; driver->id_table[i].match_flags != 0; i++) {
-                if (match_unit_directory(unit->directory, &driver->id_table[i]))
+        device = fw_device(unit->device.parent);
+
+        for (id = fw_driver(drv)->id_table; id->match_flags != 0; id++) {
+                if (match_unit_directory(unit->directory, id->match_flags, id))
+                        return 1;
+
+                /* Also check vendor ID in the root directory. */
+                if ((id->match_flags & IEEE1394_MATCH_VENDOR_ID) &&
+                    match_unit_directory(&device->config_rom[5],
+                                IEEE1394_MATCH_VENDOR_ID, id) &&
+                    match_unit_directory(unit->directory, id->match_flags
+                                & ~IEEE1394_MATCH_VENDOR_ID, id))
                         return 1;
         }