firewire: Add rom_index attribute for unit sysfs directories.

Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

1 files changed, 21 insertions, 0 deletions

diff --git a/drivers/firewire/fw-device.c b/drivers/firewire/fw-device.c
index b24090ae9c70..4ade867db888 100644
--- a/drivers/firewire/fw-device.c
+++ b/drivers/firewire/fw-device.c
@@ -230,6 +230,22 @@ static struct device_attribute config_rom_attribute = {
         .show = show_config_rom_attribute,
 };
 
+static ssize_t
+show_rom_index_attribute(struct device *dev,
+                         struct device_attribute *attr, char *buf)
+{
+        struct fw_device *device = fw_device(dev->parent);
+        struct fw_unit *unit = fw_unit(dev);
+
+        return snprintf(buf, PAGE_SIZE, "%d\n",
+                        unit->directory - device->config_rom);
+}
+
+static struct device_attribute rom_index_attribute = {
+        .attr = { .name = "rom_index", .mode = S_IRUGO, },
+        .show = show_rom_index_attribute,
+};
+
 struct read_quadlet_callback_data {
         struct completion done;
         int rcode;
@@ -393,6 +409,11 @@ static void create_units(struct fw_device *device)
                         device_unregister(&unit->device);
                         kfree(unit);
                 }
+
+                if (device_create_file(&unit->device, &rom_index_attribute) < 0) {
+                        device_unregister(&unit->device);
+                        kfree(unit);
+                }
         }
 }