firewire: cdev: amendment to "add ioctl to query maximum transmission speed"

The as yet unreleased FW_CDEV_IOC_GET_SPEED ioctl puts only a single
integer into the parameter buffer.  We can use ioctl()'s return value
instead.

(Also: Some whitespace change in firewire-cdev.h.)
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

drivers/firewire/fw-cdev.c

@@ -1214,13 +1214,14 @@ static int ioctl_deallocate_iso_resource_once(struct client *client, void *buffe
 	return init_iso_resource(client, request, ISO_RES_DEALLOC_ONCE);
 }
 
+/*
+ * Returns a speed code:  Maximum speed to or from this device,
+ * limited by the device's link speed, the local node's link speed,
+ * and all PHY port speeds between the two links.
+ */
 static int ioctl_get_speed(struct client *client, void *buffer)
 {
-	struct fw_cdev_get_speed *request = buffer;
-
-	request->max_speed = client->device->max_speed;
-
-	return 0;
+	return client->device->max_speed;
 }
 
 static int ioctl_send_broadcast_request(struct client *client, void *buffer)

include/linux/firewire-cdev.h

@@ -223,28 +223,28 @@ union fw_cdev_event {
 };
 
 /* available since kernel version 2.6.22 */
-#define FW_CDEV_IOC_GET_INFO		_IOWR('#', 0x00, struct fw_cdev_get_info)
-#define FW_CDEV_IOC_SEND_REQUEST	_IOW('#', 0x01, struct fw_cdev_send_request)
-#define FW_CDEV_IOC_ALLOCATE		_IOWR('#', 0x02, struct fw_cdev_allocate)
-#define FW_CDEV_IOC_DEALLOCATE		_IOW('#', 0x03, struct fw_cdev_deallocate)
-#define FW_CDEV_IOC_SEND_RESPONSE	_IOW('#', 0x04, struct fw_cdev_send_response)
-#define FW_CDEV_IOC_INITIATE_BUS_RESET	_IOW('#', 0x05, struct fw_cdev_initiate_bus_reset)
-#define FW_CDEV_IOC_ADD_DESCRIPTOR	_IOWR('#', 0x06, struct fw_cdev_add_descriptor)
-#define FW_CDEV_IOC_REMOVE_DESCRIPTOR	_IOW('#', 0x07, struct fw_cdev_remove_descriptor)
-#define FW_CDEV_IOC_CREATE_ISO_CONTEXT	_IOWR('#', 0x08, struct fw_cdev_create_iso_context)
-#define FW_CDEV_IOC_QUEUE_ISO		_IOWR('#', 0x09, struct fw_cdev_queue_iso)
-#define FW_CDEV_IOC_START_ISO		_IOW('#', 0x0a, struct fw_cdev_start_iso)
-#define FW_CDEV_IOC_STOP_ISO		_IOW('#', 0x0b, struct fw_cdev_stop_iso)
+#define FW_CDEV_IOC_GET_INFO           _IOWR('#', 0x00, struct fw_cdev_get_info)
+#define FW_CDEV_IOC_SEND_REQUEST        _IOW('#', 0x01, struct fw_cdev_send_request)
+#define FW_CDEV_IOC_ALLOCATE           _IOWR('#', 0x02, struct fw_cdev_allocate)
+#define FW_CDEV_IOC_DEALLOCATE          _IOW('#', 0x03, struct fw_cdev_deallocate)
+#define FW_CDEV_IOC_SEND_RESPONSE       _IOW('#', 0x04, struct fw_cdev_send_response)
+#define FW_CDEV_IOC_INITIATE_BUS_RESET  _IOW('#', 0x05, struct fw_cdev_initiate_bus_reset)
+#define FW_CDEV_IOC_ADD_DESCRIPTOR     _IOWR('#', 0x06, struct fw_cdev_add_descriptor)
+#define FW_CDEV_IOC_REMOVE_DESCRIPTOR   _IOW('#', 0x07, struct fw_cdev_remove_descriptor)
+#define FW_CDEV_IOC_CREATE_ISO_CONTEXT _IOWR('#', 0x08, struct fw_cdev_create_iso_context)
+#define FW_CDEV_IOC_QUEUE_ISO          _IOWR('#', 0x09, struct fw_cdev_queue_iso)
+#define FW_CDEV_IOC_START_ISO           _IOW('#', 0x0a, struct fw_cdev_start_iso)
+#define FW_CDEV_IOC_STOP_ISO            _IOW('#', 0x0b, struct fw_cdev_stop_iso)
 
 /* available since kernel version 2.6.24 */
-#define FW_CDEV_IOC_GET_CYCLE_TIMER	_IOR('#', 0x0c, struct fw_cdev_get_cycle_timer)
+#define FW_CDEV_IOC_GET_CYCLE_TIMER     _IOR('#', 0x0c, struct fw_cdev_get_cycle_timer)
 
 /* available since kernel version 2.6.30 */
 #define FW_CDEV_IOC_ALLOCATE_ISO_RESOURCE       _IOWR('#', 0x0d, struct fw_cdev_allocate_iso_resource)
 #define FW_CDEV_IOC_DEALLOCATE_ISO_RESOURCE      _IOW('#', 0x0e, struct fw_cdev_deallocate)
 #define FW_CDEV_IOC_ALLOCATE_ISO_RESOURCE_ONCE   _IOW('#', 0x0f, struct fw_cdev_allocate_iso_resource)
 #define FW_CDEV_IOC_DEALLOCATE_ISO_RESOURCE_ONCE _IOW('#', 0x10, struct fw_cdev_allocate_iso_resource)
-#define FW_CDEV_IOC_GET_SPEED                    _IOR('#', 0x11, struct fw_cdev_get_speed)
+#define FW_CDEV_IOC_GET_SPEED                     _IO('#', 0x11) /* returns speed code */
 #define FW_CDEV_IOC_SEND_BROADCAST_REQUEST       _IOW('#', 0x12, struct fw_cdev_send_request)
 #define FW_CDEV_IOC_SEND_STREAM_PACKET           _IOW('#', 0x13, struct fw_cdev_send_stream_packet)
 
@@ -601,15 +601,6 @@ struct fw_cdev_allocate_iso_resource {
 	__u32 handle;
 };
 
-/**
- * struct fw_cdev_get_speed - Query maximum speed to or from this device
- * @max_speed:	Speed code; minimum of the device's link speed, the local node's
- *		link speed, and all PHY port speeds between the two links
- */
-struct fw_cdev_get_speed {
-	__u32 max_speed;
-};
-
 /**
  * struct fw_cdev_send_stream_packet - send an asynchronous stream packet
  * @generation:   Bus generation where the packet is valid