firewire: Use device->groups for adding device attributes.

We dynamically create an attribute group for the key present on the
device in hand and point device->group to it.  This way the device
core adds the sysfs attributes for us as the device is added.

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

2 files changed, 28 insertions, 35 deletions

diff --git a/drivers/firewire/fw-device.c b/drivers/firewire/fw-device.c
index 2bf86aa1c9bc..5db666fd265b 100644
--- a/drivers/firewire/fw-device.c
+++ b/drivers/firewire/fw-device.c
@@ -289,32 +289,29 @@ static struct config_rom_attribute config_rom_attributes[] = {
 };
 
 static void
-remove_config_rom_attributes(struct device *dev)
-{
-        int i;
-
-        for (i = 0; i < ARRAY_SIZE(config_rom_attributes); i++)
-                device_remove_file(dev, &config_rom_attributes[i].attr);
-}
-
-static int
-add_config_rom_attributes(struct device *dev)
+init_fw_attribute_group(struct device *dev,
+                        struct device_attribute *attrs,
+                        struct fw_attribute_group *group)
 {
         struct device_attribute *attr;
-        int i, err = 0;
+        int i, j;
+
+        for (j = 0; attrs[j].attr.name != NULL; j++)
+                group->attrs[j] = &attrs[j].attr;
 
         for (i = 0; i < ARRAY_SIZE(config_rom_attributes); i++) {
                 attr = &config_rom_attributes[i].attr;
                 if (attr->show(dev, attr, NULL) < 0)
                         continue;
-                err = device_create_file(dev, attr);
-                if (err < 0) {
-                        remove_config_rom_attributes(dev);
-                        break;
-                }
+                group->attrs[j++] = &attr->attr;
         }
 
-        return err;
+        BUG_ON(j >= ARRAY_SIZE(group->attrs));
+        group->attrs[j++] = NULL;
+        group->groups[0] = &group->group;
+        group->groups[1] = NULL;
+        group->group.attrs = group->attrs;
+        dev->groups = group->groups;
 }
 
 static ssize_t
@@ -497,7 +494,6 @@ static void fw_unit_release(struct device *dev)
 }
 
 static struct device_type fw_unit_type = {
-        .attrs          = fw_unit_attributes,
         .uevent         = fw_unit_uevent,
         .release        = fw_unit_release,
 };
@@ -534,16 +530,14 @@ static void create_units(struct fw_device *device)
                 snprintf(unit->device.bus_id, sizeof unit->device.bus_id,
                          "%s.%d", device->device.bus_id, i++);
 
+                init_fw_attribute_group(&unit->device,
+                                        fw_unit_attributes,
+                                        &unit->attribute_group);
                 if (device_register(&unit->device) < 0)
                         goto skip_unit;
 
-                if (add_config_rom_attributes(&unit->device) < 0)
-                        goto skip_unregister;
-
                 continue;
 
-        skip_unregister:
-                device_unregister(&unit->device);
         skip_unit:
                 kfree(unit);
         }
@@ -551,9 +545,6 @@ static void create_units(struct fw_device *device)
 
 static int shutdown_unit(struct device *device, void *data)
 {
-        struct fw_unit *unit = fw_unit(device);
-
-        remove_config_rom_attributes(&unit->device);
         device_unregister(device);
 
         return 0;
@@ -583,15 +574,12 @@ static void fw_device_shutdown(struct work_struct *work)
         idr_remove(&fw_device_idr, minor);
         up_write(&fw_bus_type.subsys.rwsem);
 
-        remove_config_rom_attributes(&device->device);
-
         fw_device_cdev_remove(device);
         device_for_each_child(&device->device, NULL, shutdown_unit);
         device_unregister(&device->device);
 }
 
 static struct device_type fw_device_type = {
-        .attrs          = fw_device_attributes,
         .release        = fw_device_release,
 };
 
@@ -647,15 +635,14 @@ static void fw_device_init(struct work_struct *work)
         snprintf(device->device.bus_id, sizeof device->device.bus_id,
                  "fw%d", minor);
 
+        init_fw_attribute_group(&device->device,
+                                fw_device_attributes,
+                                &device->attribute_group);
         if (device_add(&device->device)) {
                 fw_error("Failed to add device.\n");
                 goto error_with_cdev;
         }
 
-        err = add_config_rom_attributes(&device->device);
-        if (err < 0)
-                goto error_with_register;
-
         create_units(device);
 
         /* Transition the device to running state.  If it got pulled
@@ -682,8 +669,6 @@ static void fw_device_init(struct work_struct *work)
 
         return;
 
- error_with_register:
-        device_unregister(&device->device);
  error_with_cdev:
         down_write(&fw_bus_type.subsys.rwsem);
         idr_remove(&fw_device_idr, minor);
diff --git a/drivers/firewire/fw-device.h b/drivers/firewire/fw-device.h
index ce47ab958840..c167d59da68a 100644
--- a/drivers/firewire/fw-device.h
+++ b/drivers/firewire/fw-device.h
@@ -32,6 +32,12 @@ enum fw_device_state {
         FW_DEVICE_SHUTDOWN,
 };
 
+struct fw_attribute_group {
+        struct attribute_group *groups[2];
+        struct attribute_group group;
+        struct attribute *attrs[11];
+};
+
 struct fw_device {
         atomic_t state;
         struct fw_node *node;
@@ -45,6 +51,7 @@ struct fw_device {
         size_t config_rom_length;
         int config_rom_retries;
         struct delayed_work work;
+        struct fw_attribute_group attribute_group;
 };
 
 static inline struct fw_device *
@@ -72,6 +79,7 @@ extern int fw_cdev_major;
 struct fw_unit {
         struct device device;
         u32 *directory;
+        struct fw_attribute_group attribute_group;
 };
 
 static inline struct fw_unit *