firewire: Document userspace ioctl interface.

The isochronous packet format is still not documented, but this is a good first step. Signed-off-by: Kristian Høgsberg <krh@redhat.com> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (format, wording)

firewire: Document userspace ioctl interface.
The isochronous packet format is still not documented, but this is a good first step. Signed-off-by: Kristian Høgsberg <krh@redhat.com> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (format, wording)
Kristian Høgsberg · Stefan Richter
1 parent 5cd54c94b0
Showing 1 changed file with 264 additions and 33 deletions Side-by-side Diff
include/linux/firewire-cdev.h
@@ -30,16 +30,38 @@
 #define FW_CDEV_EVENT_REQUEST		0x02
 #define FW_CDEV_EVENT_ISO_INTERRUPT	0x03
  
-/* The 'closure' fields are for user space to use.  Data passed in the
- * 'closure' field for a request will be returned in the corresponding
- * event.  It's a 64-bit type so that it's a fixed size type big
- * enough to hold a pointer on all platforms. */
-
+/**
+ * struct fw_cdev_event_common - Common part of all fw_cdev_event_ types
+ * @closure:	For arbitrary use by userspace
+ * @type:	Discriminates the fw_cdev_event_ types
+ *
+ * This struct may be used to access generic members of all fw_cdev_event_
+ * types regardless of the specific type.
+ *
+ * Data passed in the @closure field for a request will be returned in the
+ * corresponding event.  It is big enough to hold a pointer on all platforms.
+ * The ioctl used to set @closure depends on the @type of event.
+ */
 struct fw_cdev_event_common {
 	__u64 closure;
 	__u32 type;
 };
  
+/**
+ * struct fw_cdev_event_bus_reset - Sent when a bus reset occurred
+ * @closure:	See &fw_cdev_event_common; set by %FW_CDEV_IOC_GET_INFO ioctl
+ * @type:	See &fw_cdev_event_common; always %FW_CDEV_EVENT_BUS_RESET
+ * @node_id:       New node ID of this node
+ * @local_node_id: Node ID of the local node, i.e. of the controller
+ * @bm_node_id:    Node ID of the bus manager
+ * @irm_node_id:   Node ID of the iso resource manager
+ * @root_node_id:  Node ID of the root node
+ * @generation:    New bus generation
+ *
+ * This event is sent when the bus the device belongs to goes through a bus
+ * reset.  It provides information about the new bus configuration, such as
+ * new node ID for this device, new root ID, and others.
+ */
 struct fw_cdev_event_bus_reset {
 	__u64 closure;
 	__u32 type;
@@ -51,6 +73,20 @@
 	__u32 generation;
 };
  
+/**
+ * struct fw_cdev_event_response - Sent when a response packet was received
+ * @closure:	See &fw_cdev_event_common;
+ *		set by %FW_CDEV_IOC_SEND_REQUEST ioctl
+ * @type:	See &fw_cdev_event_common; always %FW_CDEV_EVENT_RESPONSE
+ * @rcode:	Response code returned by the remote node
+ * @length:	Data length, i.e. the response's payload size in bytes
+ * @data:	Payload data, if any
+ *
+ * This event is sent when the stack receives a response to an outgoing request
+ * sent by %FW_CDEV_IOC_SEND_REQUEST ioctl.  The payload data for responses
+ * carrying data (read and lock responses) follows immediately and can be
+ * accessed through the @data field.
+ */
 struct fw_cdev_event_response {
 	__u64 closure;
 	__u32 type;
@@ -59,6 +95,25 @@
 	__u32 data[0];
 };
  
+/**
+ * struct fw_cdev_event_request - Sent on incoming request to an address region
+ * @closure:	See &fw_cdev_event_common; set by %FW_CDEV_IOC_ALLOCATE ioctl
+ * @type:	See &fw_cdev_event_common; always %FW_CDEV_EVENT_REQUEST
+ * @tcode:	Transaction code of the incoming request
+ * @offset:	The offset into the 48-bit per-node address space
+ * @handle:	Reference to the kernel-side pending request
+ * @length:	Data length, i.e. the request's payload size in bytes
+ * @data:	Incoming data, if any
+ *
+ * This event is sent when the stack receives an incoming request to an address
+ * region registered using the %FW_CDEV_IOC_ALLOCATE ioctl.  The request is
+ * guaranteed to be completely contained in the specified region.  Userspace is
+ * responsible for sending the response by %FW_CDEV_IOC_SEND_RESPONSE ioctl,
+ * using the same @handle.
+ *
+ * The payload data for requests carrying data (write and lock requests)
+ * follows immediately and can be accessed through the @data field.
+ */
 struct fw_cdev_event_request {
 	__u64 closure;
 	__u32 type;
  
  
@@ -69,14 +124,39 @@
 	__u32 data[0];
 };
  
+/**
+ * struct fw_cdev_event_iso_interrupt - Sent when an iso packet was completed
+ * @closure:	See &fw_cdev_event_common;
+ *		set by %FW_CDEV_CREATE_ISO_CONTEXT ioctl
+ * @type:	See &fw_cdev_event_common; always %FW_CDEV_EVENT_ISO_INTERRUPT
+ * @cycle:	Cycle counter of the interrupt packet
+ * @header_length: Total length of following headers, in bytes
+ * @header:	Stripped headers, if any
+ *
+ * This event is sent when the controller has completed an &fw_cdev_iso_packet
+ * with the %FW_CDEV_ISO_INTERRUPT bit set.  In the receive case, the headers
+ * stripped of all packets up until and including the interrupt packet are
+ * returned in the @header field.
+ */
 struct fw_cdev_event_iso_interrupt {
 	__u64 closure;
 	__u32 type;
 	__u32 cycle;
-	__u32 header_length;	/* Length in bytes of following headers. */
+	__u32 header_length;
 	__u32 header[0];
 };
  
+/**
+ * union fw_cdev_event - Convenience union of fw_cdev_event_ types
+ * @common:        Valid for all types
+ * @bus_reset:     Valid if @common.type == %FW_CDEV_EVENT_BUS_RESET
+ * @response:      Valid if @common.type == %FW_CDEV_EVENT_RESPONSE
+ * @request:       Valid if @common.type == %FW_CDEV_EVENT_REQUEST
+ * @iso_interrupt: Valid if @common.type == %FW_CDEV_EVENT_ISO_INTERRUPT
+ *
+ * Convenience union for userspace use.  Events could be read(2) into a char
+ * buffer and then cast to this union for further processing.
+ */
 union fw_cdev_event {
 	struct fw_cdev_event_common common;
 	struct fw_cdev_event_bus_reset bus_reset;
  
  
  
  
  
@@ -105,35 +185,47 @@
  */
 #define FW_CDEV_VERSION		1
  
+/**
+ * struct fw_cdev_get_info - General purpose information ioctl
+ * @version:	The version field is just a running serial number.
+ *		We never break backwards compatibility, but may add more
+ *		structs and ioctls in later revisions.
+ * @rom_length:	If @rom is non-zero, at most rom_length bytes of configuration
+ *		ROM will be copied into that user space address.  In either
+ *		case, @rom_length is updated with the actual length of the
+ *		configuration ROM.
+ * @rom:	If non-zero, address of a buffer to be filled by a copy of the
+ *		local node's configuration ROM
+ * @bus_reset:	If non-zero, address of a buffer to be filled by a
+ *		&struct fw_cdev_event_bus_reset with the current state
+ *		of the bus.  This does not cause a bus reset to happen.
+ * @bus_reset_closure: Value of &closure in this and subsequent bus reset events
+ * @card:	The index of the card this device belongs to
+ */
 struct fw_cdev_get_info {
-	/* The version field is just a running serial number.  We
-	 * never break backwards compatibility.  Userspace passes in
-	 * the version it expects and the kernel passes back the
-	 * highest version it can provide.  Even if the structs in
-	 * this interface are extended in a later version, the kernel
-	 * will not copy back more data than what was present in the
-	 * interface version userspace expects. */
 	__u32 version;
-
-	/* If non-zero, at most rom_length bytes of config rom will be
-	 * copied into that user space address.  In either case,
-	 * rom_length is updated with the actual length of the config
-	 * rom. */
 	__u32 rom_length;
 	__u64 rom;
-
-	/* If non-zero, a fw_cdev_event_bus_reset struct will be
-	 * copied here with the current state of the bus.  This does
-	 * not cause a bus reset to happen.  The value of closure in
-	 * this and sub-sequent bus reset events is set to
-	 * bus_reset_closure. */
 	__u64 bus_reset;
 	__u64 bus_reset_closure;
-
-	/* The index of the card this devices belongs to. */
 	__u32 card;
 };
  
+/**
+ * struct fw_cdev_send_request - Send an asynchronous request packet
+ * @tcode:	Transaction code of the request
+ * @length:	Length of outgoing payload, in bytes
+ * @offset:	48-bit offset at destination node
+ * @closure:	Passed back to userspace in the response event
+ * @data:	Userspace pointer to payload
+ * @generation:	The bus generation where packet is valid
+ *
+ * Send a request to the device.  This ioctl implements all outgoing requests.
+ * Both quadlet and block request specify the payload as a pointer to the data
+ * in the @data field.  Once the transaction completes, the kernel writes an
+ * &fw_cdev_event_request event back.  The @closure field is passed back to
+ * user space in the response event.
+ */
 struct fw_cdev_send_request {
 	__u32 tcode;
 	__u32 length;
@@ -143,6 +235,19 @@
 	__u32 generation;
 };
  
+/**
+ * struct fw_cdev_send_response - Send an asynchronous response packet
+ * @rcode:	Response code as determined by the userspace handler
+ * @length:	Length of outgoing payload, in bytes
+ * @data:	Userspace pointer to payload
+ * @handle:	The handle from the &fw_cdev_event_request
+ *
+ * Send a response to an incoming request.  By setting up an address range using
+ * the %FW_CDEV_IOC_ALLOCATE ioctl, userspace can listen for incoming requests.  An
+ * incoming request will generate an %FW_CDEV_EVENT_REQUEST, and userspace must
+ * send a reply using this ioctl.  The event has a handle to the kernel-side
+ * pending transaction, which should be used with this ioctl.
+ */
 struct fw_cdev_send_response {
 	__u32 rcode;
 	__u32 length;
@@ -150,6 +255,21 @@
 	__u32 handle;
 };
  
+/**
+ * struct fw_cdev_allocate - Allocate a CSR address range
+ * @offset:	Start offset of the address range
+ * @closure:	To be passed back to userspace in request events
+ * @length:	Length of the address range, in bytes
+ * @handle:	Handle to the allocation, written by the kernel
+ *
+ * Allocate an address range in the 48-bit address space on the local node
+ * (the controller).  This allows userspace to listen for requests with an
+ * offset within that address range.  When the kernel receives a request
+ * within the range, an &fw_cdev_event_request event will be written back.
+ * The @closure field is passed back to userspace in the response event.
+ * The @handle field is an out parameter, returning a handle to the allocated
+ * range to be used for later deallocation of the range.
+ */
 struct fw_cdev_allocate {
 	__u64 offset;
 	__u64 closure;
@@ -157,6 +277,11 @@
 	__u32 handle;
 };
  
+/**
+ * struct fw_cdev_deallocate - Free an address range allocation
+ * @handle:	Handle to the address range, as returned by the kernel when the
+ *		range was allocated
+ */
 struct fw_cdev_deallocate {
 	__u32 handle;
 };
  
  
@@ -164,10 +289,41 @@
 #define FW_CDEV_LONG_RESET	0
 #define FW_CDEV_SHORT_RESET	1
  
+/**
+ * struct fw_cdev_initiate_bus_reset - Initiate a bus reset
+ * @type:	%FW_CDEV_SHORT_RESET or %FW_CDEV_LONG_RESET
+ *
+ * Initiate a bus reset for the bus this device is on.  The bus reset can be
+ * either the original (long) bus reset or the arbitrated (short) bus reset
+ * introduced in 1394a-2000.
+ */
 struct fw_cdev_initiate_bus_reset {
-	__u32 type;
+	__u32 type;	/* FW_CDEV_SHORT_RESET or FW_CDEV_LONG_RESET */
 };
  
+/**
+ * struct fw_cdev_add_descriptor - Add contents to the local node's config ROM
+ * @immediate:	If non-zero, immediate key to insert before pointer
+ * @key:	Upper 8 bits of root directory pointer
+ * @data:	Userspace pointer to contents of descriptor block
+ * @length:	Length of descriptor block data, in bytes
+ * @handle:	Handle to the descriptor, written by the kernel
+ *
+ * Add a descriptor block and optionally a preceding immediate key to the local
+ * node's configuration ROM.
+ *
+ * The @key field specifies the upper 8 bits of the descriptor root directory
+ * pointer and the @data and @length fields specify the contents. The @key
+ * should be of the form 0xXX000000. The offset part of the root directory entry
+ * will be filled in by the kernel.
+ *
+ * If not 0, the @immediate field specifies an immediate key which will be
+ * inserted before the root directory pointer.
+ *
+ * If successful, the kernel adds the descriptor and writes back a handle to the
+ * kernel-side object to be used for later removal of the descriptor block and
+ * immediate key.
+ */
 struct fw_cdev_add_descriptor {
 	__u32 immediate;
 	__u32 key;
@@ -176,6 +332,14 @@
 	__u32 handle;
 };
  
+/**
+ * struct fw_cdev_remove_descriptor - Remove contents from the configuration ROM
+ * @handle:	Handle to the descriptor, as returned by the kernel when the
+ *		descriptor was added
+ *
+ * Remove a descriptor block and accompanying immediate key from the local
+ * node's configuration ROM.
+ */
 struct fw_cdev_remove_descriptor {
 	__u32 handle;
 };
@@ -183,12 +347,24 @@
 #define FW_CDEV_ISO_CONTEXT_TRANSMIT	0
 #define FW_CDEV_ISO_CONTEXT_RECEIVE	1
  
-#define FW_CDEV_ISO_CONTEXT_MATCH_TAG0		 1
-#define FW_CDEV_ISO_CONTEXT_MATCH_TAG1		 2
-#define FW_CDEV_ISO_CONTEXT_MATCH_TAG2		 4
-#define FW_CDEV_ISO_CONTEXT_MATCH_TAG3		 8
-#define FW_CDEV_ISO_CONTEXT_MATCH_ALL_TAGS	15
-
+/**
+ * struct fw_cdev_create_iso_context - Create a context for isochronous IO
+ * @type:	%FW_CDEV_ISO_CONTEXT_TRANSMIT or %FW_CDEV_ISO_CONTEXT_RECEIVE
+ * @header_size: Header size to strip for receive contexts
+ * @channel:	Channel to bind to
+ * @speed:	Speed to transmit at
+ * @closure:	To be returned in &fw_cdev_event_iso_interrupt
+ * @handle:	Handle to context, written back by kernel
+ *
+ * Prior to sending or receiving isochronous I/O, a context must be created.
+ * The context records information about the transmit or receive configuration
+ * and typically maps to an underlying hardware resource.  A context is set up
+ * for either sending or receiving.  It is bound to a specific isochronous
+ * channel.
+ *
+ * If a context was successfully created, the kernel writes back a handle to the
+ * context, which must be passed in for subsequent operations on that context.
+ */
 struct fw_cdev_create_iso_context {
 	__u32 type;
 	__u32 header_size;
  
  
@@ -201,15 +377,49 @@
 #define FW_CDEV_ISO_PAYLOAD_LENGTH(v)	(v)
 #define FW_CDEV_ISO_INTERRUPT		(1 << 16)
 #define FW_CDEV_ISO_SKIP		(1 << 17)
+#define FW_CDEV_ISO_SYNC		(1 << 17)
 #define FW_CDEV_ISO_TAG(v)		((v) << 18)
 #define FW_CDEV_ISO_SY(v)		((v) << 20)
 #define FW_CDEV_ISO_HEADER_LENGTH(v)	((v) << 24)
  
+/**
+ * struct fw_cdev_iso_packet - Isochronous packet
+ * @control:	Contains the header length (8 uppermost bits), the sy field
+ *		(4 bits), the tag field (2 bits), a sync flag (1 bit),
+ *		a skip flag (1 bit), an interrupt flag (1 bit), and the
+ *		payload length (16 lowermost bits)
+ * @header:	Header and payload
+ *
+ * &struct fw_cdev_iso_packet is used to describe isochronous packet queues.
+ *
+ * Use the FW_CDEV_ISO_ macros to fill in @control.  The sy and tag fields are
+ * specified by IEEE 1394a and IEC 61883.
+ *
+ * FIXME - finish this documentation
+ */
 struct fw_cdev_iso_packet {
 	__u32 control;
 	__u32 header[0];
 };
  
+/**
+ * struct fw_cdev_queue_iso - Queue isochronous packets for I/O
+ * @packets:	Userspace pointer to packet data
+ * @data:	Pointer into mmap()'ed payload buffer
+ * @size:	Size of packet data in bytes
+ * @handle:	Isochronous context handle
+ *
+ * Queue a number of isochronous packets for reception or transmission.
+ * This ioctl takes a pointer to an array of &fw_cdev_iso_packet structs,
+ * which describe how to transmit from or receive into a contiguous region
+ * of a mmap()'ed payload buffer.  As part of the packet descriptors,
+ * a series of headers can be supplied, which will be prepended to the
+ * payload during DMA.
+ *
+ * The kernel may or may not queue all packets, but will write back updated
+ * values of the @packets, @data and @size fields, so the ioctl can be
+ * resubmitted easily.
+ */
 struct fw_cdev_queue_iso {
 	__u64 packets;
 	__u64 data;
@@ -217,6 +427,23 @@
 	__u32 handle;
 };
  
+#define FW_CDEV_ISO_CONTEXT_MATCH_TAG0		 1
+#define FW_CDEV_ISO_CONTEXT_MATCH_TAG1		 2
+#define FW_CDEV_ISO_CONTEXT_MATCH_TAG2		 4
+#define FW_CDEV_ISO_CONTEXT_MATCH_TAG3		 8
+#define FW_CDEV_ISO_CONTEXT_MATCH_ALL_TAGS	15
+
+/**
+ * struct fw_cdev_start_iso - Start an isochronous transmission or reception
+ * @cycle:	Cycle in which to start I/O.  If @cycle is greater than or
+ *		equal to 0, the I/O will start on that cycle.
+ * @sync:	Determines the value to wait for for receive packets that have
+ *		the %FW_CDEV_ISO_SYNC bit set
+ * @tags:	Tag filter bit mask.  Only valid for isochronous reception.
+ *		Determines the tag values for which packets will be accepted.
+ *		Use FW_CDEV_ISO_CONTEXT_MATCH_ macros to set @tags.
+ * @handle:	Isochronous context handle within which to transmit or receive
+ */
 struct fw_cdev_start_iso {
 	__s32 cycle;
 	__u32 sync;
@@ -224,6 +451,10 @@
 	__u32 handle;
 };
  
+/**
+ * struct fw_cdev_stop_iso - Stop an isochronous transmission or reception
+ * @handle:	Handle of isochronous context to stop
+ */
 struct fw_cdev_stop_iso {
 	__u32 handle;
 };
...	...	@@ -30,16 +30,38 @@
30	30	#define FW_CDEV_EVENT_REQUEST 0x02
31	31	#define FW_CDEV_EVENT_ISO_INTERRUPT 0x03
32	32
33		-/* The 'closure' fields are for user space to use. Data passed in the
34		- * 'closure' field for a request will be returned in the corresponding
35		- * event. It's a 64-bit type so that it's a fixed size type big
36		- * enough to hold a pointer on all platforms. */
37		-
	33	+/**
	34	+ * struct fw_cdev_event_common - Common part of all fw_cdev_event_ types
	35	+ * @closure: For arbitrary use by userspace
	36	+ * @type: Discriminates the fw_cdev_event_ types
	37	+ *
	38	+ * This struct may be used to access generic members of all fw_cdev_event_
	39	+ * types regardless of the specific type.
	40	+ *
	41	+ * Data passed in the @closure field for a request will be returned in the
	42	+ * corresponding event. It is big enough to hold a pointer on all platforms.
	43	+ * The ioctl used to set @closure depends on the @type of event.
	44	+ */
38	45	struct fw_cdev_event_common {
39	46	__u64 closure;
40	47	__u32 type;
41	48	};
42	49
	50	+/**
	51	+ * struct fw_cdev_event_bus_reset - Sent when a bus reset occurred
	52	+ * @closure: See &fw_cdev_event_common; set by %FW_CDEV_IOC_GET_INFO ioctl
	53	+ * @type: See &fw_cdev_event_common; always %FW_CDEV_EVENT_BUS_RESET
	54	+ * @node_id: New node ID of this node
	55	+ * @local_node_id: Node ID of the local node, i.e. of the controller
	56	+ * @bm_node_id: Node ID of the bus manager
	57	+ * @irm_node_id: Node ID of the iso resource manager
	58	+ * @root_node_id: Node ID of the root node
	59	+ * @generation: New bus generation
	60	+ *
	61	+ * This event is sent when the bus the device belongs to goes through a bus
	62	+ * reset. It provides information about the new bus configuration, such as
	63	+ * new node ID for this device, new root ID, and others.
	64	+ */
43	65	struct fw_cdev_event_bus_reset {
44	66	__u64 closure;
45	67	__u32 type;
...	...	@@ -51,6 +73,20 @@
51	73	__u32 generation;
52	74	};
53	75
	76	+/**
	77	+ * struct fw_cdev_event_response - Sent when a response packet was received
	78	+ * @closure: See &fw_cdev_event_common;
	79	+ * set by %FW_CDEV_IOC_SEND_REQUEST ioctl
	80	+ * @type: See &fw_cdev_event_common; always %FW_CDEV_EVENT_RESPONSE
	81	+ * @rcode: Response code returned by the remote node
	82	+ * @length: Data length, i.e. the response's payload size in bytes
	83	+ * @data: Payload data, if any
	84	+ *
	85	+ * This event is sent when the stack receives a response to an outgoing request
	86	+ * sent by %FW_CDEV_IOC_SEND_REQUEST ioctl. The payload data for responses
	87	+ * carrying data (read and lock responses) follows immediately and can be
	88	+ * accessed through the @data field.
	89	+ */
54	90	struct fw_cdev_event_response {
55	91	__u64 closure;
56	92	__u32 type;
...	...	@@ -59,6 +95,25 @@
59	95	__u32 data[0];
60	96	};
61	97
	98	+/**
	99	+ * struct fw_cdev_event_request - Sent on incoming request to an address region
	100	+ * @closure: See &fw_cdev_event_common; set by %FW_CDEV_IOC_ALLOCATE ioctl
	101	+ * @type: See &fw_cdev_event_common; always %FW_CDEV_EVENT_REQUEST
	102	+ * @tcode: Transaction code of the incoming request
	103	+ * @offset: The offset into the 48-bit per-node address space
	104	+ * @handle: Reference to the kernel-side pending request
	105	+ * @length: Data length, i.e. the request's payload size in bytes
	106	+ * @data: Incoming data, if any
	107	+ *
	108	+ * This event is sent when the stack receives an incoming request to an address
	109	+ * region registered using the %FW_CDEV_IOC_ALLOCATE ioctl. The request is
	110	+ * guaranteed to be completely contained in the specified region. Userspace is
	111	+ * responsible for sending the response by %FW_CDEV_IOC_SEND_RESPONSE ioctl,
	112	+ * using the same @handle.
	113	+ *
	114	+ * The payload data for requests carrying data (write and lock requests)
	115	+ * follows immediately and can be accessed through the @data field.
	116	+ */
62	117	struct fw_cdev_event_request {
63	118	__u64 closure;
64	119	__u32 type;
65	120
66	121
...	...	@@ -69,14 +124,39 @@
69	124	__u32 data[0];
70	125	};
71	126
	127	+/**
	128	+ * struct fw_cdev_event_iso_interrupt - Sent when an iso packet was completed
	129	+ * @closure: See &fw_cdev_event_common;
	130	+ * set by %FW_CDEV_CREATE_ISO_CONTEXT ioctl
	131	+ * @type: See &fw_cdev_event_common; always %FW_CDEV_EVENT_ISO_INTERRUPT
	132	+ * @cycle: Cycle counter of the interrupt packet
	133	+ * @header_length: Total length of following headers, in bytes
	134	+ * @header: Stripped headers, if any
	135	+ *
	136	+ * This event is sent when the controller has completed an &fw_cdev_iso_packet
	137	+ * with the %FW_CDEV_ISO_INTERRUPT bit set. In the receive case, the headers
	138	+ * stripped of all packets up until and including the interrupt packet are
	139	+ * returned in the @header field.
	140	+ */
72	141	struct fw_cdev_event_iso_interrupt {
73	142	__u64 closure;
74	143	__u32 type;
75	144	__u32 cycle;
76		- __u32 header_length; /* Length in bytes of following headers. */
	145	+ __u32 header_length;
77	146	__u32 header[0];
78	147	};
79	148
	149	+/**
	150	+ * union fw_cdev_event - Convenience union of fw_cdev_event_ types
	151	+ * @common: Valid for all types
	152	+ * @bus_reset: Valid if @common.type == %FW_CDEV_EVENT_BUS_RESET
	153	+ * @response: Valid if @common.type == %FW_CDEV_EVENT_RESPONSE
	154	+ * @request: Valid if @common.type == %FW_CDEV_EVENT_REQUEST
	155	+ * @iso_interrupt: Valid if @common.type == %FW_CDEV_EVENT_ISO_INTERRUPT
	156	+ *
	157	+ * Convenience union for userspace use. Events could be read(2) into a char
	158	+ * buffer and then cast to this union for further processing.
	159	+ */
80	160	union fw_cdev_event {
81	161	struct fw_cdev_event_common common;
82	162	struct fw_cdev_event_bus_reset bus_reset;
83	163
84	164
85	165
86	166
87	167
...	...	@@ -105,35 +185,47 @@
105	185	*/
106	186	#define FW_CDEV_VERSION 1
107	187
	188	+/**
	189	+ * struct fw_cdev_get_info - General purpose information ioctl
	190	+ * @version: The version field is just a running serial number.
	191	+ * We never break backwards compatibility, but may add more
	192	+ * structs and ioctls in later revisions.
	193	+ * @rom_length: If @rom is non-zero, at most rom_length bytes of configuration
	194	+ * ROM will be copied into that user space address. In either
	195	+ * case, @rom_length is updated with the actual length of the
	196	+ * configuration ROM.
	197	+ * @rom: If non-zero, address of a buffer to be filled by a copy of the
	198	+ * local node's configuration ROM
	199	+ * @bus_reset: If non-zero, address of a buffer to be filled by a
	200	+ * &struct fw_cdev_event_bus_reset with the current state
	201	+ * of the bus. This does not cause a bus reset to happen.
	202	+ * @bus_reset_closure: Value of &closure in this and subsequent bus reset events
	203	+ * @card: The index of the card this device belongs to
	204	+ */
108	205	struct fw_cdev_get_info {
109		- /* The version field is just a running serial number. We
110		- * never break backwards compatibility. Userspace passes in
111		- * the version it expects and the kernel passes back the
112		- * highest version it can provide. Even if the structs in
113		- * this interface are extended in a later version, the kernel
114		- * will not copy back more data than what was present in the
115		- * interface version userspace expects. */
116	206	__u32 version;
117		-
118		- /* If non-zero, at most rom_length bytes of config rom will be
119		- * copied into that user space address. In either case,
120		- * rom_length is updated with the actual length of the config
121		- * rom. */
122	207	__u32 rom_length;
123	208	__u64 rom;
124		-
125		- /* If non-zero, a fw_cdev_event_bus_reset struct will be
126		- * copied here with the current state of the bus. This does
127		- * not cause a bus reset to happen. The value of closure in
128		- * this and sub-sequent bus reset events is set to
129		- * bus_reset_closure. */
130	209	__u64 bus_reset;
131	210	__u64 bus_reset_closure;
132		-
133		- /* The index of the card this devices belongs to. */
134	211	__u32 card;
135	212	};
136	213
	214	+/**
	215	+ * struct fw_cdev_send_request - Send an asynchronous request packet
	216	+ * @tcode: Transaction code of the request
	217	+ * @length: Length of outgoing payload, in bytes
	218	+ * @offset: 48-bit offset at destination node
	219	+ * @closure: Passed back to userspace in the response event
	220	+ * @data: Userspace pointer to payload
	221	+ * @generation: The bus generation where packet is valid
	222	+ *
	223	+ * Send a request to the device. This ioctl implements all outgoing requests.
	224	+ * Both quadlet and block request specify the payload as a pointer to the data
	225	+ * in the @data field. Once the transaction completes, the kernel writes an
	226	+ * &fw_cdev_event_request event back. The @closure field is passed back to
	227	+ * user space in the response event.
	228	+ */
137	229	struct fw_cdev_send_request {
138	230	__u32 tcode;
139	231	__u32 length;
...	...	@@ -143,6 +235,19 @@
143	235	__u32 generation;
144	236	};
145	237
	238	+/**
	239	+ * struct fw_cdev_send_response - Send an asynchronous response packet
	240	+ * @rcode: Response code as determined by the userspace handler
	241	+ * @length: Length of outgoing payload, in bytes
	242	+ * @data: Userspace pointer to payload
	243	+ * @handle: The handle from the &fw_cdev_event_request
	244	+ *
	245	+ * Send a response to an incoming request. By setting up an address range using
	246	+ * the %FW_CDEV_IOC_ALLOCATE ioctl, userspace can listen for incoming requests. An
	247	+ * incoming request will generate an %FW_CDEV_EVENT_REQUEST, and userspace must
	248	+ * send a reply using this ioctl. The event has a handle to the kernel-side
	249	+ * pending transaction, which should be used with this ioctl.
	250	+ */
146	251	struct fw_cdev_send_response {
147	252	__u32 rcode;
148	253	__u32 length;
...	...	@@ -150,6 +255,21 @@
150	255	__u32 handle;
151	256	};
152	257
	258	+/**
	259	+ * struct fw_cdev_allocate - Allocate a CSR address range
	260	+ * @offset: Start offset of the address range
	261	+ * @closure: To be passed back to userspace in request events
	262	+ * @length: Length of the address range, in bytes
	263	+ * @handle: Handle to the allocation, written by the kernel
	264	+ *
	265	+ * Allocate an address range in the 48-bit address space on the local node
	266	+ * (the controller). This allows userspace to listen for requests with an
	267	+ * offset within that address range. When the kernel receives a request
	268	+ * within the range, an &fw_cdev_event_request event will be written back.
	269	+ * The @closure field is passed back to userspace in the response event.
	270	+ * The @handle field is an out parameter, returning a handle to the allocated
	271	+ * range to be used for later deallocation of the range.
	272	+ */
153	273	struct fw_cdev_allocate {
154	274	__u64 offset;
155	275	__u64 closure;
...	...	@@ -157,6 +277,11 @@
157	277	__u32 handle;
158	278	};
159	279
	280	+/**
	281	+ * struct fw_cdev_deallocate - Free an address range allocation
	282	+ * @handle: Handle to the address range, as returned by the kernel when the
	283	+ * range was allocated
	284	+ */
160	285	struct fw_cdev_deallocate {
161	286	__u32 handle;
162	287	};
163	288
164	289
...	...	@@ -164,10 +289,41 @@
164	289	#define FW_CDEV_LONG_RESET 0
165	290	#define FW_CDEV_SHORT_RESET 1
166	291
	292	+/**
	293	+ * struct fw_cdev_initiate_bus_reset - Initiate a bus reset
	294	+ * @type: %FW_CDEV_SHORT_RESET or %FW_CDEV_LONG_RESET
	295	+ *
	296	+ * Initiate a bus reset for the bus this device is on. The bus reset can be
	297	+ * either the original (long) bus reset or the arbitrated (short) bus reset
	298	+ * introduced in 1394a-2000.
	299	+ */
167	300	struct fw_cdev_initiate_bus_reset {
168		- __u32 type;
	301	+ __u32 type; /* FW_CDEV_SHORT_RESET or FW_CDEV_LONG_RESET */
169	302	};
170	303
	304	+/**
	305	+ * struct fw_cdev_add_descriptor - Add contents to the local node's config ROM
	306	+ * @immediate: If non-zero, immediate key to insert before pointer
	307	+ * @key: Upper 8 bits of root directory pointer
	308	+ * @data: Userspace pointer to contents of descriptor block
	309	+ * @length: Length of descriptor block data, in bytes
	310	+ * @handle: Handle to the descriptor, written by the kernel
	311	+ *
	312	+ * Add a descriptor block and optionally a preceding immediate key to the local
	313	+ * node's configuration ROM.
	314	+ *
	315	+ * The @key field specifies the upper 8 bits of the descriptor root directory
	316	+ * pointer and the @data and @length fields specify the contents. The @key
	317	+ * should be of the form 0xXX000000. The offset part of the root directory entry
	318	+ * will be filled in by the kernel.
	319	+ *
	320	+ * If not 0, the @immediate field specifies an immediate key which will be
	321	+ * inserted before the root directory pointer.
	322	+ *
	323	+ * If successful, the kernel adds the descriptor and writes back a handle to the
	324	+ * kernel-side object to be used for later removal of the descriptor block and
	325	+ * immediate key.
	326	+ */
171	327	struct fw_cdev_add_descriptor {
172	328	__u32 immediate;
173	329	__u32 key;
...	...	@@ -176,6 +332,14 @@
176	332	__u32 handle;
177	333	};
178	334
	335	+/**
	336	+ * struct fw_cdev_remove_descriptor - Remove contents from the configuration ROM
	337	+ * @handle: Handle to the descriptor, as returned by the kernel when the
	338	+ * descriptor was added
	339	+ *
	340	+ * Remove a descriptor block and accompanying immediate key from the local
	341	+ * node's configuration ROM.
	342	+ */
179	343	struct fw_cdev_remove_descriptor {
180	344	__u32 handle;
181	345	};
...	...	@@ -183,12 +347,24 @@
183	347	#define FW_CDEV_ISO_CONTEXT_TRANSMIT 0
184	348	#define FW_CDEV_ISO_CONTEXT_RECEIVE 1
185	349
186		-#define FW_CDEV_ISO_CONTEXT_MATCH_TAG0 1
187		-#define FW_CDEV_ISO_CONTEXT_MATCH_TAG1 2
188		-#define FW_CDEV_ISO_CONTEXT_MATCH_TAG2 4
189		-#define FW_CDEV_ISO_CONTEXT_MATCH_TAG3 8
190		-#define FW_CDEV_ISO_CONTEXT_MATCH_ALL_TAGS 15
191		-
	350	+/**
	351	+ * struct fw_cdev_create_iso_context - Create a context for isochronous IO
	352	+ * @type: %FW_CDEV_ISO_CONTEXT_TRANSMIT or %FW_CDEV_ISO_CONTEXT_RECEIVE
	353	+ * @header_size: Header size to strip for receive contexts
	354	+ * @channel: Channel to bind to
	355	+ * @speed: Speed to transmit at
	356	+ * @closure: To be returned in &fw_cdev_event_iso_interrupt
	357	+ * @handle: Handle to context, written back by kernel
	358	+ *
	359	+ * Prior to sending or receiving isochronous I/O, a context must be created.
	360	+ * The context records information about the transmit or receive configuration
	361	+ * and typically maps to an underlying hardware resource. A context is set up
	362	+ * for either sending or receiving. It is bound to a specific isochronous
	363	+ * channel.
	364	+ *
	365	+ * If a context was successfully created, the kernel writes back a handle to the
	366	+ * context, which must be passed in for subsequent operations on that context.
	367	+ */
192	368	struct fw_cdev_create_iso_context {
193	369	__u32 type;
194	370	__u32 header_size;
195	371
196	372
...	...	@@ -201,15 +377,49 @@
201	377	#define FW_CDEV_ISO_PAYLOAD_LENGTH(v) (v)
202	378	#define FW_CDEV_ISO_INTERRUPT (1 << 16)
203	379	#define FW_CDEV_ISO_SKIP (1 << 17)
	380	+#define FW_CDEV_ISO_SYNC (1 << 17)
204	381	#define FW_CDEV_ISO_TAG(v) ((v) << 18)
205	382	#define FW_CDEV_ISO_SY(v) ((v) << 20)
206	383	#define FW_CDEV_ISO_HEADER_LENGTH(v) ((v) << 24)
207	384
	385	+/**
	386	+ * struct fw_cdev_iso_packet - Isochronous packet
	387	+ * @control: Contains the header length (8 uppermost bits), the sy field
	388	+ * (4 bits), the tag field (2 bits), a sync flag (1 bit),
	389	+ * a skip flag (1 bit), an interrupt flag (1 bit), and the
	390	+ * payload length (16 lowermost bits)
	391	+ * @header: Header and payload
	392	+ *
	393	+ * &struct fw_cdev_iso_packet is used to describe isochronous packet queues.
	394	+ *
	395	+ * Use the FW_CDEV_ISO_ macros to fill in @control. The sy and tag fields are
	396	+ * specified by IEEE 1394a and IEC 61883.
	397	+ *
	398	+ * FIXME - finish this documentation
	399	+ */
208	400	struct fw_cdev_iso_packet {
209	401	__u32 control;
210	402	__u32 header[0];
211	403	};
212	404
	405	+/**
	406	+ * struct fw_cdev_queue_iso - Queue isochronous packets for I/O
	407	+ * @packets: Userspace pointer to packet data
	408	+ * @data: Pointer into mmap()'ed payload buffer
	409	+ * @size: Size of packet data in bytes
	410	+ * @handle: Isochronous context handle
	411	+ *
	412	+ * Queue a number of isochronous packets for reception or transmission.
	413	+ * This ioctl takes a pointer to an array of &fw_cdev_iso_packet structs,
	414	+ * which describe how to transmit from or receive into a contiguous region
	415	+ * of a mmap()'ed payload buffer. As part of the packet descriptors,
	416	+ * a series of headers can be supplied, which will be prepended to the
	417	+ * payload during DMA.
	418	+ *
	419	+ * The kernel may or may not queue all packets, but will write back updated
	420	+ * values of the @packets, @data and @size fields, so the ioctl can be
	421	+ * resubmitted easily.
	422	+ */
213	423	struct fw_cdev_queue_iso {
214	424	__u64 packets;
215	425	__u64 data;
...	...	@@ -217,6 +427,23 @@
217	427	__u32 handle;
218	428	};
219	429
	430	+#define FW_CDEV_ISO_CONTEXT_MATCH_TAG0 1
	431	+#define FW_CDEV_ISO_CONTEXT_MATCH_TAG1 2
	432	+#define FW_CDEV_ISO_CONTEXT_MATCH_TAG2 4
	433	+#define FW_CDEV_ISO_CONTEXT_MATCH_TAG3 8
	434	+#define FW_CDEV_ISO_CONTEXT_MATCH_ALL_TAGS 15
	435	+
	436	+/**
	437	+ * struct fw_cdev_start_iso - Start an isochronous transmission or reception
	438	+ * @cycle: Cycle in which to start I/O. If @cycle is greater than or
	439	+ * equal to 0, the I/O will start on that cycle.
	440	+ * @sync: Determines the value to wait for for receive packets that have
	441	+ * the %FW_CDEV_ISO_SYNC bit set
	442	+ * @tags: Tag filter bit mask. Only valid for isochronous reception.
	443	+ * Determines the tag values for which packets will be accepted.
	444	+ * Use FW_CDEV_ISO_CONTEXT_MATCH_ macros to set @tags.
	445	+ * @handle: Isochronous context handle within which to transmit or receive
	446	+ */
220	447	struct fw_cdev_start_iso {
221	448	__s32 cycle;
222	449	__u32 sync;
...	...	@@ -224,6 +451,10 @@
224	451	__u32 handle;
225	452	};
226	453
	454	+/**
	455	+ * struct fw_cdev_stop_iso - Stop an isochronous transmission or reception
	456	+ * @handle: Handle of isochronous context to stop
	457	+ */
227	458	struct fw_cdev_stop_iso {
228	459	__u32 handle;
229	460	};