[mirror_ubuntu-artful-kernel.git] / drivers / ieee1394 / iso.h

/*
 * IEEE 1394 for Linux
 *
 * kernel ISO transmission/reception
 *
 * Copyright (C) 2002 Maas Digital LLC
 *
 * This code is licensed under the GPL.  See the file COPYING in the root
 * directory of the kernel sources for details.
 */

#ifndef IEEE1394_ISO_H
#define IEEE1394_ISO_H

#include "hosts.h"
#include "dma.h"

/* high-level ISO interface */

/* This API sends and receives isochronous packets on a large,
   virtually-contiguous kernel memory buffer. The buffer may be mapped
   into a user-space process for zero-copy transmission and reception.

   There are no explicit boundaries between packets in the buffer. A
   packet may be transmitted or received at any location. However,
   low-level drivers may impose certain restrictions on alignment or
   size of packets. (e.g. in OHCI no packet may cross a page boundary,
   and packets should be quadlet-aligned)
*/

/* Packet descriptor - the API maintains a ring buffer of these packet
   descriptors in kernel memory (hpsb_iso.infos[]).  */

struct hpsb_iso_packet_info {
	/* offset of data payload relative to the first byte of the buffer */
	__u32 offset;

	/* length of the data payload, in bytes (not including the isochronous header) */
	__u16 len;

	/* (recv only) the cycle number (mod 8000) on which the packet was received */
	__u16 cycle;

	/* (recv only) channel on which the packet was received */
	__u8 channel;

	/* 2-bit 'tag' and 4-bit 'sy' fields of the isochronous header */
	__u8 tag;
	__u8 sy;

	/*
	 * length in bytes of the packet including header/trailer.
	 * MUST be at structure end, since the first part of this structure is also 
	 * defined in raw1394.h (i.e. struct raw1394_iso_packet_info), is copied to 
	 * userspace and is accessed there through libraw1394. 
	 */
	__u16 total_len;
};

enum hpsb_iso_type { HPSB_ISO_RECV = 0, HPSB_ISO_XMIT = 1 };

/* The mode of the dma when receiving iso data. Must be supported by chip */
enum raw1394_iso_dma_recv_mode {
	HPSB_ISO_DMA_DEFAULT = -1,
	HPSB_ISO_DMA_OLD_ABI = 0,
	HPSB_ISO_DMA_BUFFERFILL = 1,
	HPSB_ISO_DMA_PACKET_PER_BUFFER = 2
};

struct hpsb_iso {
	enum hpsb_iso_type type;

	/* pointer to low-level driver and its private data */
	struct hpsb_host *host;
	void *hostdata;

	/* a function to be called (from interrupt context) after
           outgoing packets have been sent, or incoming packets have
           arrived */
	void (*callback)(struct hpsb_iso*);

	/* wait for buffer space */
	wait_queue_head_t waitq;

	int speed; /* IEEE1394_SPEED_100, 200, or 400 */
	int channel; /* -1 if multichannel */
	int dma_mode; /* dma receive mode */


	/* greatest # of packets between interrupts - controls
	   the maximum latency of the buffer */
	int irq_interval;

	/* the buffer for packet data payloads */
	struct dma_region data_buf;

	/* size of data_buf, in bytes (always a multiple of PAGE_SIZE) */
	unsigned int buf_size;

	/* # of packets in the ringbuffer */
	unsigned int buf_packets;

	/* protects packet cursors */
	spinlock_t lock;

	/* the index of the next packet that will be produced
	   or consumed by the user */
	int first_packet;

	/* the index of the next packet that will be transmitted
	   or received by the 1394 hardware */
	int pkt_dma;

	/* how many packets, starting at first_packet:
	   (transmit) are ready to be filled with data
	   (receive)  contain received data */
	int n_ready_packets;

	/* how many times the buffer has overflowed or underflowed */
	atomic_t overflows;

	/* Current number of bytes lost in discarded packets */
	int bytes_discarded;

	/* private flags to track initialization progress */
#define HPSB_ISO_DRIVER_INIT     (1<<0)
#define HPSB_ISO_DRIVER_STARTED  (1<<1)
	unsigned int flags;

	/* # of packets left to prebuffer (xmit only) */
	int prebuffer;

	/* starting cycle for DMA (xmit only) */
	int start_cycle;

	/* cycle at which next packet will be transmitted,
	   -1 if not known */
	int xmit_cycle;

	/* ringbuffer of packet descriptors in regular kernel memory
	 * XXX Keep this last, since we use over-allocated memory from
	 * this entry to fill this field. */
	struct hpsb_iso_packet_info *infos;
};

/* functions available to high-level drivers (e.g. raw1394) */

/* allocate the buffer and DMA context */

struct hpsb_iso* hpsb_iso_xmit_init(struct hpsb_host *host,
				    unsigned int data_buf_size,
				    unsigned int buf_packets,
				    int channel,
				    int speed,
				    int irq_interval,
				    void (*callback)(struct hpsb_iso*));

/* note: if channel = -1, multi-channel receive is enabled */
struct hpsb_iso* hpsb_iso_recv_init(struct hpsb_host *host,
				    unsigned int data_buf_size,
				    unsigned int buf_packets,
				    int channel,
				    int dma_mode,
				    int irq_interval,
				    void (*callback)(struct hpsb_iso*));

/* multi-channel only */
int hpsb_iso_recv_listen_channel(struct hpsb_iso *iso, unsigned char channel);
int hpsb_iso_recv_unlisten_channel(struct hpsb_iso *iso, unsigned char channel);
int hpsb_iso_recv_set_channel_mask(struct hpsb_iso *iso, u64 mask);

/* start/stop DMA */
int hpsb_iso_xmit_start(struct hpsb_iso *iso, int start_on_cycle, int prebuffer);
int hpsb_iso_recv_start(struct hpsb_iso *iso, int start_on_cycle, int tag_mask, int sync);
void hpsb_iso_stop(struct hpsb_iso *iso);

/* deallocate buffer and DMA context */
void hpsb_iso_shutdown(struct hpsb_iso *iso);

/* queue a packet for transmission. 'offset' is relative to the beginning of the
   DMA buffer, where the packet's data payload should already have been placed */
int hpsb_iso_xmit_queue_packet(struct hpsb_iso *iso, u32 offset, u16 len, u8 tag, u8 sy);

/* wait until all queued packets have been transmitted to the bus */
int hpsb_iso_xmit_sync(struct hpsb_iso *iso);

/* N packets have been read out of the buffer, re-use the buffer space */
int  hpsb_iso_recv_release_packets(struct hpsb_iso *recv, unsigned int n_packets);

/* check for arrival of new packets immediately (even if irq_interval
   has not yet been reached) */
int hpsb_iso_recv_flush(struct hpsb_iso *iso);

/* returns # of packets ready to send or receive */
int hpsb_iso_n_ready(struct hpsb_iso *iso);

/* the following are callbacks available to low-level drivers */

/* call after a packet has been transmitted to the bus (interrupt context is OK)
   'cycle' is the _exact_ cycle the packet was sent on
   'error' should be non-zero if some sort of error occurred when sending the packet
*/
void hpsb_iso_packet_sent(struct hpsb_iso *iso, int cycle, int error);

/* call after a packet has been received (interrupt context OK) */
void hpsb_iso_packet_received(struct hpsb_iso *iso, u32 offset, u16 len,
			      u16 total_len, u16 cycle, u8 channel, u8 tag, u8 sy);

/* call to wake waiting processes after buffer space has opened up. */
void hpsb_iso_wake(struct hpsb_iso *iso);

#endif /* IEEE1394_ISO_H */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* IEEE 1394 for Linux
	3	*
	4	* kernel ISO transmission/reception
	5	*
	6	* Copyright (C) 2002 Maas Digital LLC
	7	*
	8	* This code is licensed under the GPL. See the file COPYING in the root
	9	* directory of the kernel sources for details.
	10	*/
	11
	12	#ifndef IEEE1394_ISO_H
	13	#define IEEE1394_ISO_H
	14
	15	#include "hosts.h"
	16	#include "dma.h"
	17
	18	/* high-level ISO interface */
	19
	20	/* This API sends and receives isochronous packets on a large,
	21	virtually-contiguous kernel memory buffer. The buffer may be mapped
	22	into a user-space process for zero-copy transmission and reception.
	23
	24	There are no explicit boundaries between packets in the buffer. A
	25	packet may be transmitted or received at any location. However,
	26	low-level drivers may impose certain restrictions on alignment or
	27	size of packets. (e.g. in OHCI no packet may cross a page boundary,
	28	and packets should be quadlet-aligned)
	29	*/
	30
	31	/* Packet descriptor - the API maintains a ring buffer of these packet
	32	descriptors in kernel memory (hpsb_iso.infos[]). */
	33
	34	struct hpsb_iso_packet_info {
	35	/* offset of data payload relative to the first byte of the buffer */
	36	__u32 offset;
	37
	38	/* length of the data payload, in bytes (not including the isochronous header) */
	39	__u16 len;
	40
	41	/* (recv only) the cycle number (mod 8000) on which the packet was received */
	42	__u16 cycle;
	43
	44	/* (recv only) channel on which the packet was received */
	45	__u8 channel;
	46
	47	/* 2-bit 'tag' and 4-bit 'sy' fields of the isochronous header */
	48	__u8 tag;
	49	__u8 sy;
1934b8b6 BC	50
	51	/*
	52	* length in bytes of the packet including header/trailer.
	53	* MUST be at structure end, since the first part of this structure is also
	54	* defined in raw1394.h (i.e. struct raw1394_iso_packet_info), is copied to
	55	* userspace and is accessed there through libraw1394.
	56	*/
	57	__u16 total_len;
1da177e4 LT	58	};
	59
	60	enum hpsb_iso_type { HPSB_ISO_RECV = 0, HPSB_ISO_XMIT = 1 };
	61
	62	/* The mode of the dma when receiving iso data. Must be supported by chip */
	63	enum raw1394_iso_dma_recv_mode {
	64	HPSB_ISO_DMA_DEFAULT = -1,
	65	HPSB_ISO_DMA_OLD_ABI = 0,
	66	HPSB_ISO_DMA_BUFFERFILL = 1,
	67	HPSB_ISO_DMA_PACKET_PER_BUFFER = 2
	68	};
	69
	70	struct hpsb_iso {
	71	enum hpsb_iso_type type;
	72
	73	/* pointer to low-level driver and its private data */
	74	struct hpsb_host *host;
	75	void *hostdata;
	76
	77	/* a function to be called (from interrupt context) after
	78	outgoing packets have been sent, or incoming packets have
	79	arrived */
	80	void (callback)(struct hpsb_iso);
	81
	82	/* wait for buffer space */
	83	wait_queue_head_t waitq;
	84
	85	int speed; /* IEEE1394_SPEED_100, 200, or 400 */
	86	int channel; /* -1 if multichannel */
	87	int dma_mode; /* dma receive mode */
	88
	89
	90	/* greatest # of packets between interrupts - controls
	91	the maximum latency of the buffer */
	92	int irq_interval;
	93
	94	/* the buffer for packet data payloads */
	95	struct dma_region data_buf;
	96
	97	/* size of data_buf, in bytes (always a multiple of PAGE_SIZE) */
	98	unsigned int buf_size;
	99
	100	/* # of packets in the ringbuffer */
	101	unsigned int buf_packets;
	102
	103	/* protects packet cursors */
	104	spinlock_t lock;
	105
	106	/* the index of the next packet that will be produced
	107	or consumed by the user */
	108	int first_packet;
	109
	110	/* the index of the next packet that will be transmitted
	111	or received by the 1394 hardware */
	112	int pkt_dma;
	113
	114	/* how many packets, starting at first_packet:
	115	(transmit) are ready to be filled with data
	116	(receive) contain received data */
	117	int n_ready_packets;
	118
	119	/* how many times the buffer has overflowed or underflowed */
	120	atomic_t overflows;
	121
1934b8b6 BC	122	/* Current number of bytes lost in discarded packets */
	123	int bytes_discarded;
	124
1da177e4 LT	125	/* private flags to track initialization progress */
	126	#define HPSB_ISO_DRIVER_INIT (1<<0)
	127	#define HPSB_ISO_DRIVER_STARTED (1<<1)
	128	unsigned int flags;
	129
	130	/* # of packets left to prebuffer (xmit only) */
	131	int prebuffer;
	132
	133	/* starting cycle for DMA (xmit only) */
	134	int start_cycle;
	135
	136	/* cycle at which next packet will be transmitted,
	137	-1 if not known */
	138	int xmit_cycle;
	139
	140	/* ringbuffer of packet descriptors in regular kernel memory
	141	* XXX Keep this last, since we use over-allocated memory from
	142	* this entry to fill this field. */
	143	struct hpsb_iso_packet_info *infos;
	144	};
	145
	146	/* functions available to high-level drivers (e.g. raw1394) */
	147
	148	/* allocate the buffer and DMA context */
	149
	150	struct hpsb_iso* hpsb_iso_xmit_init(struct hpsb_host *host,
	151	unsigned int data_buf_size,
	152	unsigned int buf_packets,
	153	int channel,
	154	int speed,
	155	int irq_interval,
	156	void (callback)(struct hpsb_iso));
	157
	158	/* note: if channel = -1, multi-channel receive is enabled */
	159	struct hpsb_iso* hpsb_iso_recv_init(struct hpsb_host *host,
	160	unsigned int data_buf_size,
	161	unsigned int buf_packets,
	162	int channel,
	163	int dma_mode,
	164	int irq_interval,
	165	void (callback)(struct hpsb_iso));
	166
	167	/* multi-channel only */
	168	int hpsb_iso_recv_listen_channel(struct hpsb_iso *iso, unsigned char channel);
	169	int hpsb_iso_recv_unlisten_channel(struct hpsb_iso *iso, unsigned char channel);
	170	int hpsb_iso_recv_set_channel_mask(struct hpsb_iso *iso, u64 mask);
	171
	172	/* start/stop DMA */
	173	int hpsb_iso_xmit_start(struct hpsb_iso *iso, int start_on_cycle, int prebuffer);
	174	int hpsb_iso_recv_start(struct hpsb_iso *iso, int start_on_cycle, int tag_mask, int sync);
	175	void hpsb_iso_stop(struct hpsb_iso *iso);
	176
	177	/* deallocate buffer and DMA context */
	178	void hpsb_iso_shutdown(struct hpsb_iso *iso);
	179
	180	/* queue a packet for transmission. 'offset' is relative to the beginning of the
	181	DMA buffer, where the packet's data payload should already have been placed */
	182	int hpsb_iso_xmit_queue_packet(struct hpsb_iso *iso, u32 offset, u16 len, u8 tag, u8 sy);
	183
	184	/* wait until all queued packets have been transmitted to the bus */
	185	int hpsb_iso_xmit_sync(struct hpsb_iso *iso);
	186
	187	/* N packets have been read out of the buffer, re-use the buffer space */
	188	int hpsb_iso_recv_release_packets(struct hpsb_iso *recv, unsigned int n_packets);
189
190	/* check for arrival of new packets immediately (even if irq_interval
191	has not yet been reached) */
192	int hpsb_iso_recv_flush(struct hpsb_iso *iso);
193
194	/* returns # of packets ready to send or receive */
195	int hpsb_iso_n_ready(struct hpsb_iso *iso);
196
197	/* the following are callbacks available to low-level drivers */
198
199	/* call after a packet has been transmitted to the bus (interrupt context is OK)
200	'cycle' is the _exact_ cycle the packet was sent on
201	'error' should be non-zero if some sort of error occurred when sending the packet
202	*/
203	void hpsb_iso_packet_sent(struct hpsb_iso *iso, int cycle, int error);
204
205	/* call after a packet has been received (interrupt context OK) */
206	void hpsb_iso_packet_received(struct hpsb_iso *iso, u32 offset, u16 len,
1934b8b6	207	u16 total_len, u16 cycle, u8 channel, u8 tag, u8 sy);
1da177e4 LT	208
	209	/* call to wake waiting processes after buffer space has opened up. */
	210	void hpsb_iso_wake(struct hpsb_iso *iso);
	211
	212	#endif /* IEEE1394_ISO_H */