firewire: Document userspace ioctl interface. (7ada60e3) · Commits · e / devices / android_kernel_oneplus_sm7250

include/linux/firewire-cdev.h

+264 −33

Original line number	Original line	Diff line number	Diff line
	@@ -30,16 +30,38 @@
	#define FW_CDEV_EVENT_REQUEST 0x02		#define FW_CDEV_EVENT_REQUEST 0x02
	#define FW_CDEV_EVENT_ISO_INTERRUPT 0x03		#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		* struct fw_cdev_event_common - Common part of all fw_cdev_event_ types
	* event. It's a 64-bit type so that it's a fixed size type big		* @closure: For arbitrary use by userspace
	* enough to hold a pointer on all platforms. */		* @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 {		struct fw_cdev_event_common {
	__u64 closure;		__u64 closure;
	__u32 type;		__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 {		struct fw_cdev_event_bus_reset {
	__u64 closure;		__u64 closure;
	__u32 type;		__u32 type;
	@@ -51,6 +73,20 @@ struct fw_cdev_event_bus_reset {
	__u32 generation;		__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 {		struct fw_cdev_event_response {
	__u64 closure;		__u64 closure;
	__u32 type;		__u32 type;
	@@ -59,6 +95,25 @@ struct fw_cdev_event_response {
	__u32 data[0];		__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 {		struct fw_cdev_event_request {
	__u64 closure;		__u64 closure;
	__u32 type;		__u32 type;
	@@ -69,14 +124,39 @@ struct fw_cdev_event_request {
	__u32 data[0];		__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 {		struct fw_cdev_event_iso_interrupt {
	__u64 closure;		__u64 closure;
	__u32 type;		__u32 type;
	__u32 cycle;		__u32 cycle;
	__u32 header_length; /* Length in bytes of following headers. */		__u32 header_length;
	__u32 header[0];		__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 {		union fw_cdev_event {
	struct fw_cdev_event_common common;		struct fw_cdev_event_common common;
	struct fw_cdev_event_bus_reset bus_reset;		struct fw_cdev_event_bus_reset bus_reset;
	@@ -105,35 +185,47 @@ union fw_cdev_event {
	*/		*/
	#define FW_CDEV_VERSION 1		#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 {		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;		__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;		__u32 rom_length;
	__u64 rom;		__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;
	__u64 bus_reset_closure;		__u64 bus_reset_closure;

	/* The index of the card this devices belongs to. */
	__u32 card;		__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 {		struct fw_cdev_send_request {
	__u32 tcode;		__u32 tcode;
	__u32 length;		__u32 length;
	@@ -143,6 +235,19 @@ struct fw_cdev_send_request {
	__u32 generation;		__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 {		struct fw_cdev_send_response {
	__u32 rcode;		__u32 rcode;
	__u32 length;		__u32 length;
	@@ -150,6 +255,21 @@ struct fw_cdev_send_response {
	__u32 handle;		__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 {		struct fw_cdev_allocate {
	__u64 offset;		__u64 offset;
	__u64 closure;		__u64 closure;
	@@ -157,6 +277,11 @@ struct fw_cdev_allocate {
	__u32 handle;		__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 {		struct fw_cdev_deallocate {
	__u32 handle;		__u32 handle;
	};		};
	@@ -164,10 +289,41 @@ struct fw_cdev_deallocate {
	#define FW_CDEV_LONG_RESET 0		#define FW_CDEV_LONG_RESET 0
	#define FW_CDEV_SHORT_RESET 1		#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 {		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 {		struct fw_cdev_add_descriptor {
	__u32 immediate;		__u32 immediate;
	__u32 key;		__u32 key;
	@@ -176,6 +332,14 @@ struct fw_cdev_add_descriptor {
	__u32 handle;		__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 {		struct fw_cdev_remove_descriptor {
	__u32 handle;		__u32 handle;
	};		};
	@@ -183,12 +347,24 @@ struct fw_cdev_remove_descriptor {
	#define FW_CDEV_ISO_CONTEXT_TRANSMIT 0		#define FW_CDEV_ISO_CONTEXT_TRANSMIT 0
	#define FW_CDEV_ISO_CONTEXT_RECEIVE 1		#define FW_CDEV_ISO_CONTEXT_RECEIVE 1

	#define FW_CDEV_ISO_CONTEXT_MATCH_TAG0 1		/**
	#define FW_CDEV_ISO_CONTEXT_MATCH_TAG1 2		* struct fw_cdev_create_iso_context - Create a context for isochronous IO
	#define FW_CDEV_ISO_CONTEXT_MATCH_TAG2 4		* @type: %FW_CDEV_ISO_CONTEXT_TRANSMIT or %FW_CDEV_ISO_CONTEXT_RECEIVE
	#define FW_CDEV_ISO_CONTEXT_MATCH_TAG3 8		* @header_size: Header size to strip for receive contexts
	#define FW_CDEV_ISO_CONTEXT_MATCH_ALL_TAGS 15		* @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 {		struct fw_cdev_create_iso_context {
	__u32 type;		__u32 type;
	__u32 header_size;		__u32 header_size;
	@@ -201,15 +377,49 @@ struct fw_cdev_create_iso_context {
	#define FW_CDEV_ISO_PAYLOAD_LENGTH(v) (v)		#define FW_CDEV_ISO_PAYLOAD_LENGTH(v) (v)
	#define FW_CDEV_ISO_INTERRUPT (1 << 16)		#define FW_CDEV_ISO_INTERRUPT (1 << 16)
	#define FW_CDEV_ISO_SKIP (1 << 17)		#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_TAG(v) ((v) << 18)
	#define FW_CDEV_ISO_SY(v) ((v) << 20)		#define FW_CDEV_ISO_SY(v) ((v) << 20)
	#define FW_CDEV_ISO_HEADER_LENGTH(v) ((v) << 24)		#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 {		struct fw_cdev_iso_packet {
	__u32 control;		__u32 control;
	__u32 header[0];		__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 {		struct fw_cdev_queue_iso {
	__u64 packets;		__u64 packets;
	__u64 data;		__u64 data;
	@@ -217,6 +427,23 @@ struct fw_cdev_queue_iso {
	__u32 handle;		__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 {		struct fw_cdev_start_iso {
	__s32 cycle;		__s32 cycle;
	__u32 sync;		__u32 sync;
	@@ -224,6 +451,10 @@ struct fw_cdev_start_iso {
	__u32 handle;		__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 {		struct fw_cdev_stop_iso {
	__u32 handle;		__u32 handle;
	};		};