2 * Audio and Music Data Transmission Protocol (IEC 61883-6) streams
3 * with Common Isochronous Packet (IEC 61883-1) headers
5 * Copyright (c) Clemens Ladisch <clemens@ladisch.de>
6 * Licensed under the terms of the GNU General Public License, version 2.
9 #include <linux/device.h>
10 #include <linux/err.h>
11 #include <linux/firewire.h>
12 #include <linux/module.h>
13 #include <linux/slab.h>
14 #include <linux/sched.h>
15 #include <sound/pcm.h>
16 #include <sound/pcm_params.h>
17 #include <sound/rawmidi.h>
20 #define TICKS_PER_CYCLE 3072
21 #define CYCLES_PER_SECOND 8000
22 #define TICKS_PER_SECOND (TICKS_PER_CYCLE * CYCLES_PER_SECOND)
25 * Nominally 3125 bytes/second, but the MIDI port's clock might be
26 * 1% too slow, and the bus clock 100 ppm too fast.
28 #define MIDI_BYTES_PER_SECOND 3093
31 * Several devices look only at the first eight data blocks.
32 * In any case, this is more than enough for the MIDI data rate.
34 #define MAX_MIDI_RX_BLOCKS 8
36 #define TRANSFER_DELAY_TICKS 0x2e00 /* 479.17 microseconds */
38 /* isochronous header parameters */
39 #define ISO_DATA_LENGTH_SHIFT 16
42 /* common isochronous packet header parameters */
43 #define CIP_EOH_SHIFT 31
44 #define CIP_EOH (1u << CIP_EOH_SHIFT)
45 #define CIP_EOH_MASK 0x80000000
46 #define CIP_SID_SHIFT 24
47 #define CIP_SID_MASK 0x3f000000
48 #define CIP_DBS_MASK 0x00ff0000
49 #define CIP_DBS_SHIFT 16
50 #define CIP_DBC_MASK 0x000000ff
51 #define CIP_FMT_SHIFT 24
52 #define CIP_FMT_MASK 0x3f000000
53 #define CIP_FDF_MASK 0x00ff0000
54 #define CIP_FDF_SHIFT 16
55 #define CIP_SYT_MASK 0x0000ffff
56 #define CIP_SYT_NO_INFO 0xffff
59 * Audio and Music transfer protocol specific parameters
60 * only "Clock-based rate control mode" is supported
62 #define CIP_FMT_AM (0x10 << CIP_FMT_SHIFT)
63 #define AMDTP_FDF_AM824 (0 << (CIP_FDF_SHIFT + 3))
64 #define AMDTP_FDF_NO_DATA 0xff
66 /* TODO: make these configurable */
67 #define INTERRUPT_INTERVAL 16
68 #define QUEUE_LENGTH 48
70 #define IN_PACKET_HEADER_SIZE 4
71 #define OUT_PACKET_HEADER_SIZE 0
73 static void pcm_period_tasklet(unsigned long data
);
76 * amdtp_stream_init - initialize an AMDTP stream structure
77 * @s: the AMDTP stream to initialize
78 * @unit: the target of the stream
79 * @dir: the direction of stream
80 * @flags: the packet transmission method to use
82 int amdtp_stream_init(struct amdtp_stream
*s
, struct fw_unit
*unit
,
83 enum amdtp_stream_direction dir
, enum cip_flags flags
)
88 s
->context
= ERR_PTR(-1);
89 mutex_init(&s
->mutex
);
90 tasklet_init(&s
->period_tasklet
, pcm_period_tasklet
, (unsigned long)s
);
93 init_waitqueue_head(&s
->callback_wait
);
94 s
->callbacked
= false;
99 EXPORT_SYMBOL(amdtp_stream_init
);
102 * amdtp_stream_destroy - free stream resources
103 * @s: the AMDTP stream to destroy
105 void amdtp_stream_destroy(struct amdtp_stream
*s
)
107 WARN_ON(amdtp_stream_running(s
));
108 mutex_destroy(&s
->mutex
);
110 EXPORT_SYMBOL(amdtp_stream_destroy
);
112 const unsigned int amdtp_syt_intervals
[CIP_SFC_COUNT
] = {
116 [CIP_SFC_88200
] = 16,
117 [CIP_SFC_96000
] = 16,
118 [CIP_SFC_176400
] = 32,
119 [CIP_SFC_192000
] = 32,
121 EXPORT_SYMBOL(amdtp_syt_intervals
);
123 const unsigned int amdtp_rate_table
[CIP_SFC_COUNT
] = {
124 [CIP_SFC_32000
] = 32000,
125 [CIP_SFC_44100
] = 44100,
126 [CIP_SFC_48000
] = 48000,
127 [CIP_SFC_88200
] = 88200,
128 [CIP_SFC_96000
] = 96000,
129 [CIP_SFC_176400
] = 176400,
130 [CIP_SFC_192000
] = 192000,
132 EXPORT_SYMBOL(amdtp_rate_table
);
135 * amdtp_stream_add_pcm_hw_constraints - add hw constraints for PCM substream
136 * @s: the AMDTP stream, which must be initialized.
137 * @runtime: the PCM substream runtime
139 int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream
*s
,
140 struct snd_pcm_runtime
*runtime
)
144 /* AM824 in IEC 61883-6 can deliver 24bit data */
145 err
= snd_pcm_hw_constraint_msbits(runtime
, 0, 32, 24);
150 * Currently firewire-lib processes 16 packets in one software
151 * interrupt callback. This equals to 2msec but actually the
152 * interval of the interrupts has a jitter.
153 * Additionally, even if adding a constraint to fit period size to
154 * 2msec, actual calculated frames per period doesn't equal to 2msec,
155 * depending on sampling rate.
156 * Anyway, the interval to call snd_pcm_period_elapsed() cannot 2msec.
157 * Here let us use 5msec for safe period interrupt.
159 err
= snd_pcm_hw_constraint_minmax(runtime
,
160 SNDRV_PCM_HW_PARAM_PERIOD_TIME
,
165 /* Non-Blocking stream has no more constraints */
166 if (!(s
->flags
& CIP_BLOCKING
))
170 * One AMDTP packet can include some frames. In blocking mode, the
171 * number equals to SYT_INTERVAL. So the number is 8, 16 or 32,
172 * depending on its sampling rate. For accurate period interrupt, it's
173 * preferrable to align period/buffer sizes to current SYT_INTERVAL.
175 * TODO: These constraints can be improved with proper rules.
176 * Currently apply LCM of SYT_INTERVALs.
178 err
= snd_pcm_hw_constraint_step(runtime
, 0,
179 SNDRV_PCM_HW_PARAM_PERIOD_SIZE
, 32);
182 err
= snd_pcm_hw_constraint_step(runtime
, 0,
183 SNDRV_PCM_HW_PARAM_BUFFER_SIZE
, 32);
187 EXPORT_SYMBOL(amdtp_stream_add_pcm_hw_constraints
);
190 * amdtp_stream_set_parameters - set stream parameters
191 * @s: the AMDTP stream to configure
192 * @rate: the sample rate
193 * @pcm_channels: the number of PCM samples in each data block, to be encoded
194 * as AM824 multi-bit linear audio
195 * @midi_ports: the number of MIDI ports (i.e., MPX-MIDI Data Channels)
197 * The parameters must be set before the stream is started, and must not be
198 * changed while the stream is running.
200 void amdtp_stream_set_parameters(struct amdtp_stream
*s
,
202 unsigned int pcm_channels
,
203 unsigned int midi_ports
)
205 unsigned int i
, sfc
, midi_channels
;
207 midi_channels
= DIV_ROUND_UP(midi_ports
, 8);
209 if (WARN_ON(amdtp_stream_running(s
)) |
210 WARN_ON(pcm_channels
> AMDTP_MAX_CHANNELS_FOR_PCM
) |
211 WARN_ON(midi_channels
> AMDTP_MAX_CHANNELS_FOR_MIDI
))
214 for (sfc
= 0; sfc
< ARRAY_SIZE(amdtp_rate_table
); ++sfc
)
215 if (amdtp_rate_table
[sfc
] == rate
)
221 s
->pcm_channels
= pcm_channels
;
223 s
->data_block_quadlets
= s
->pcm_channels
+ midi_channels
;
224 s
->midi_ports
= midi_ports
;
226 s
->syt_interval
= amdtp_syt_intervals
[sfc
];
228 /* default buffering in the device */
229 s
->transfer_delay
= TRANSFER_DELAY_TICKS
- TICKS_PER_CYCLE
;
230 if (s
->flags
& CIP_BLOCKING
)
231 /* additional buffering needed to adjust for no-data packets */
232 s
->transfer_delay
+= TICKS_PER_SECOND
* s
->syt_interval
/ rate
;
234 /* init the position map for PCM and MIDI channels */
235 for (i
= 0; i
< pcm_channels
; i
++)
236 s
->pcm_positions
[i
] = i
;
237 s
->midi_position
= s
->pcm_channels
;
240 * We do not know the actual MIDI FIFO size of most devices. Just
241 * assume two bytes, i.e., one byte can be received over the bus while
242 * the previous one is transmitted over MIDI.
243 * (The value here is adjusted for midi_ratelimit_per_packet().)
245 s
->midi_fifo_limit
= rate
- MIDI_BYTES_PER_SECOND
* s
->syt_interval
+ 1;
247 EXPORT_SYMBOL(amdtp_stream_set_parameters
);
250 * amdtp_stream_get_max_payload - get the stream's packet size
251 * @s: the AMDTP stream
253 * This function must not be called before the stream has been configured
254 * with amdtp_stream_set_parameters().
256 unsigned int amdtp_stream_get_max_payload(struct amdtp_stream
*s
)
258 unsigned int multiplier
= 1;
260 if (s
->flags
& CIP_JUMBO_PAYLOAD
)
263 return 8 + s
->syt_interval
* s
->data_block_quadlets
* 4 * multiplier
;
265 EXPORT_SYMBOL(amdtp_stream_get_max_payload
);
267 static void write_pcm_s16(struct amdtp_stream
*s
,
268 struct snd_pcm_substream
*pcm
,
269 __be32
*buffer
, unsigned int frames
);
270 static void write_pcm_s32(struct amdtp_stream
*s
,
271 struct snd_pcm_substream
*pcm
,
272 __be32
*buffer
, unsigned int frames
);
273 static void read_pcm_s32(struct amdtp_stream
*s
,
274 struct snd_pcm_substream
*pcm
,
275 __be32
*buffer
, unsigned int frames
);
278 * amdtp_stream_set_pcm_format - set the PCM format
279 * @s: the AMDTP stream to configure
280 * @format: the format of the ALSA PCM device
282 * The sample format must be set after the other parameters (rate/PCM channels/
283 * MIDI) and before the stream is started, and must not be changed while the
286 void amdtp_stream_set_pcm_format(struct amdtp_stream
*s
,
287 snd_pcm_format_t format
)
289 if (WARN_ON(amdtp_stream_pcm_running(s
)))
296 case SNDRV_PCM_FORMAT_S16
:
297 if (s
->direction
== AMDTP_OUT_STREAM
) {
298 s
->transfer_samples
= write_pcm_s16
;
303 case SNDRV_PCM_FORMAT_S32
:
304 if (s
->direction
== AMDTP_OUT_STREAM
)
305 s
->transfer_samples
= write_pcm_s32
;
307 s
->transfer_samples
= read_pcm_s32
;
311 EXPORT_SYMBOL(amdtp_stream_set_pcm_format
);
314 * amdtp_stream_pcm_prepare - prepare PCM device for running
315 * @s: the AMDTP stream
317 * This function should be called from the PCM device's .prepare callback.
319 void amdtp_stream_pcm_prepare(struct amdtp_stream
*s
)
321 tasklet_kill(&s
->period_tasklet
);
322 s
->pcm_buffer_pointer
= 0;
323 s
->pcm_period_pointer
= 0;
324 s
->pointer_flush
= true;
326 EXPORT_SYMBOL(amdtp_stream_pcm_prepare
);
328 static unsigned int calculate_data_blocks(struct amdtp_stream
*s
,
331 unsigned int phase
, data_blocks
;
334 if (s
->flags
& CIP_BLOCKING
) {
335 /* This module generate empty packet for 'no data'. */
336 if (syt
== CIP_SYT_NO_INFO
)
339 data_blocks
= s
->syt_interval
;
340 /* Non-blocking mode. */
342 if (!cip_sfc_is_base_44100(s
->sfc
)) {
343 /* Sample_rate / 8000 is an integer, and precomputed. */
344 data_blocks
= s
->data_block_state
;
346 phase
= s
->data_block_state
;
349 * This calculates the number of data blocks per packet so that
350 * 1) the overall rate is correct and exactly synchronized to
352 * 2) packets with a rounded-up number of blocks occur as early
353 * as possible in the sequence (to prevent underruns of the
356 if (s
->sfc
== CIP_SFC_44100
)
357 /* 6 6 5 6 5 6 5 ... */
358 data_blocks
= 5 + ((phase
& 1) ^
359 (phase
== 0 || phase
>= 40));
361 /* 12 11 11 11 11 ... or 23 22 22 22 22 ... */
362 data_blocks
= 11 * (s
->sfc
>> 1) + (phase
== 0);
363 if (++phase
>= (80 >> (s
->sfc
>> 1)))
365 s
->data_block_state
= phase
;
372 static unsigned int calculate_syt(struct amdtp_stream
*s
,
375 unsigned int syt_offset
, phase
, index
, syt
;
377 if (s
->last_syt_offset
< TICKS_PER_CYCLE
) {
378 if (!cip_sfc_is_base_44100(s
->sfc
))
379 syt_offset
= s
->last_syt_offset
+ s
->syt_offset_state
;
382 * The time, in ticks, of the n'th SYT_INTERVAL sample is:
383 * n * SYT_INTERVAL * 24576000 / sample_rate
384 * Modulo TICKS_PER_CYCLE, the difference between successive
385 * elements is about 1386.23. Rounding the results of this
386 * formula to the SYT precision results in a sequence of
387 * differences that begins with:
388 * 1386 1386 1387 1386 1386 1386 1387 1386 1386 1386 1387 ...
389 * This code generates _exactly_ the same sequence.
391 phase
= s
->syt_offset_state
;
393 syt_offset
= s
->last_syt_offset
;
394 syt_offset
+= 1386 + ((index
&& !(index
& 3)) ||
398 s
->syt_offset_state
= phase
;
401 syt_offset
= s
->last_syt_offset
- TICKS_PER_CYCLE
;
402 s
->last_syt_offset
= syt_offset
;
404 if (syt_offset
< TICKS_PER_CYCLE
) {
405 syt_offset
+= s
->transfer_delay
;
406 syt
= (cycle
+ syt_offset
/ TICKS_PER_CYCLE
) << 12;
407 syt
+= syt_offset
% TICKS_PER_CYCLE
;
409 return syt
& CIP_SYT_MASK
;
411 return CIP_SYT_NO_INFO
;
415 static void write_pcm_s32(struct amdtp_stream
*s
,
416 struct snd_pcm_substream
*pcm
,
417 __be32
*buffer
, unsigned int frames
)
419 struct snd_pcm_runtime
*runtime
= pcm
->runtime
;
420 unsigned int channels
, remaining_frames
, i
, c
;
423 channels
= s
->pcm_channels
;
424 src
= (void *)runtime
->dma_area
+
425 frames_to_bytes(runtime
, s
->pcm_buffer_pointer
);
426 remaining_frames
= runtime
->buffer_size
- s
->pcm_buffer_pointer
;
428 for (i
= 0; i
< frames
; ++i
) {
429 for (c
= 0; c
< channels
; ++c
) {
430 buffer
[s
->pcm_positions
[c
]] =
431 cpu_to_be32((*src
>> 8) | 0x40000000);
434 buffer
+= s
->data_block_quadlets
;
435 if (--remaining_frames
== 0)
436 src
= (void *)runtime
->dma_area
;
440 static void write_pcm_s16(struct amdtp_stream
*s
,
441 struct snd_pcm_substream
*pcm
,
442 __be32
*buffer
, unsigned int frames
)
444 struct snd_pcm_runtime
*runtime
= pcm
->runtime
;
445 unsigned int channels
, remaining_frames
, i
, c
;
448 channels
= s
->pcm_channels
;
449 src
= (void *)runtime
->dma_area
+
450 frames_to_bytes(runtime
, s
->pcm_buffer_pointer
);
451 remaining_frames
= runtime
->buffer_size
- s
->pcm_buffer_pointer
;
453 for (i
= 0; i
< frames
; ++i
) {
454 for (c
= 0; c
< channels
; ++c
) {
455 buffer
[s
->pcm_positions
[c
]] =
456 cpu_to_be32((*src
<< 8) | 0x42000000);
459 buffer
+= s
->data_block_quadlets
;
460 if (--remaining_frames
== 0)
461 src
= (void *)runtime
->dma_area
;
465 static void read_pcm_s32(struct amdtp_stream
*s
,
466 struct snd_pcm_substream
*pcm
,
467 __be32
*buffer
, unsigned int frames
)
469 struct snd_pcm_runtime
*runtime
= pcm
->runtime
;
470 unsigned int channels
, remaining_frames
, i
, c
;
473 channels
= s
->pcm_channels
;
474 dst
= (void *)runtime
->dma_area
+
475 frames_to_bytes(runtime
, s
->pcm_buffer_pointer
);
476 remaining_frames
= runtime
->buffer_size
- s
->pcm_buffer_pointer
;
478 for (i
= 0; i
< frames
; ++i
) {
479 for (c
= 0; c
< channels
; ++c
) {
480 *dst
= be32_to_cpu(buffer
[s
->pcm_positions
[c
]]) << 8;
483 buffer
+= s
->data_block_quadlets
;
484 if (--remaining_frames
== 0)
485 dst
= (void *)runtime
->dma_area
;
489 static void write_pcm_silence(struct amdtp_stream
*s
,
490 __be32
*buffer
, unsigned int frames
)
494 for (i
= 0; i
< frames
; ++i
) {
495 for (c
= 0; c
< s
->pcm_channels
; ++c
)
496 buffer
[s
->pcm_positions
[c
]] = cpu_to_be32(0x40000000);
497 buffer
+= s
->data_block_quadlets
;
502 * To avoid sending MIDI bytes at too high a rate, assume that the receiving
503 * device has a FIFO, and track how much it is filled. This values increases
504 * by one whenever we send one byte in a packet, but the FIFO empties at
505 * a constant rate independent of our packet rate. One packet has syt_interval
506 * samples, so the number of bytes that empty out of the FIFO, per packet(!),
507 * is MIDI_BYTES_PER_SECOND * syt_interval / sample_rate. To avoid storing
508 * fractional values, the values in midi_fifo_used[] are measured in bytes
509 * multiplied by the sample rate.
511 static bool midi_ratelimit_per_packet(struct amdtp_stream
*s
, unsigned int port
)
515 used
= s
->midi_fifo_used
[port
];
516 if (used
== 0) /* common shortcut */
519 used
-= MIDI_BYTES_PER_SECOND
* s
->syt_interval
;
521 s
->midi_fifo_used
[port
] = used
;
523 return used
< s
->midi_fifo_limit
;
526 static void midi_rate_use_one_byte(struct amdtp_stream
*s
, unsigned int port
)
528 s
->midi_fifo_used
[port
] += amdtp_rate_table
[s
->sfc
];
531 static void write_midi_messages(struct amdtp_stream
*s
,
532 __be32
*buffer
, unsigned int frames
)
534 unsigned int f
, port
;
537 for (f
= 0; f
< frames
; f
++) {
538 b
= (u8
*)&buffer
[s
->midi_position
];
540 port
= (s
->data_block_counter
+ f
) % 8;
541 if (f
< MAX_MIDI_RX_BLOCKS
&&
542 midi_ratelimit_per_packet(s
, port
) &&
543 s
->midi
[port
] != NULL
&&
544 snd_rawmidi_transmit(s
->midi
[port
], &b
[1], 1) == 1) {
545 midi_rate_use_one_byte(s
, port
);
554 buffer
+= s
->data_block_quadlets
;
558 static void read_midi_messages(struct amdtp_stream
*s
,
559 __be32
*buffer
, unsigned int frames
)
561 unsigned int f
, port
;
565 for (f
= 0; f
< frames
; f
++) {
566 port
= (s
->data_block_counter
+ f
) % 8;
567 b
= (u8
*)&buffer
[s
->midi_position
];
570 if ((1 <= len
) && (len
<= 3) && (s
->midi
[port
]))
571 snd_rawmidi_receive(s
->midi
[port
], b
+ 1, len
);
573 buffer
+= s
->data_block_quadlets
;
577 static void update_pcm_pointers(struct amdtp_stream
*s
,
578 struct snd_pcm_substream
*pcm
,
584 * In IEC 61883-6, one data block represents one event. In ALSA, one
585 * event equals to one PCM frame. But Dice has a quirk to transfer
586 * two PCM frames in one data block.
588 if (s
->double_pcm_frames
)
591 ptr
= s
->pcm_buffer_pointer
+ frames
;
592 if (ptr
>= pcm
->runtime
->buffer_size
)
593 ptr
-= pcm
->runtime
->buffer_size
;
594 ACCESS_ONCE(s
->pcm_buffer_pointer
) = ptr
;
596 s
->pcm_period_pointer
+= frames
;
597 if (s
->pcm_period_pointer
>= pcm
->runtime
->period_size
) {
598 s
->pcm_period_pointer
-= pcm
->runtime
->period_size
;
599 s
->pointer_flush
= false;
600 tasklet_hi_schedule(&s
->period_tasklet
);
604 static void pcm_period_tasklet(unsigned long data
)
606 struct amdtp_stream
*s
= (void *)data
;
607 struct snd_pcm_substream
*pcm
= ACCESS_ONCE(s
->pcm
);
610 snd_pcm_period_elapsed(pcm
);
613 static int queue_packet(struct amdtp_stream
*s
,
614 unsigned int header_length
,
615 unsigned int payload_length
, bool skip
)
617 struct fw_iso_packet p
= {0};
620 if (IS_ERR(s
->context
))
623 p
.interrupt
= IS_ALIGNED(s
->packet_index
+ 1, INTERRUPT_INTERVAL
);
625 p
.header_length
= header_length
;
626 p
.payload_length
= (!skip
) ? payload_length
: 0;
628 err
= fw_iso_context_queue(s
->context
, &p
, &s
->buffer
.iso_buffer
,
629 s
->buffer
.packets
[s
->packet_index
].offset
);
631 dev_err(&s
->unit
->device
, "queueing error: %d\n", err
);
635 if (++s
->packet_index
>= QUEUE_LENGTH
)
641 static inline int queue_out_packet(struct amdtp_stream
*s
,
642 unsigned int payload_length
, bool skip
)
644 return queue_packet(s
, OUT_PACKET_HEADER_SIZE
,
645 payload_length
, skip
);
648 static inline int queue_in_packet(struct amdtp_stream
*s
)
650 return queue_packet(s
, IN_PACKET_HEADER_SIZE
,
651 amdtp_stream_get_max_payload(s
), false);
654 static int handle_out_packet(struct amdtp_stream
*s
, unsigned int data_blocks
,
658 unsigned int payload_length
;
659 struct snd_pcm_substream
*pcm
;
661 buffer
= s
->buffer
.packets
[s
->packet_index
].buffer
;
662 buffer
[0] = cpu_to_be32(ACCESS_ONCE(s
->source_node_id_field
) |
663 (s
->data_block_quadlets
<< CIP_DBS_SHIFT
) |
664 s
->data_block_counter
);
665 buffer
[1] = cpu_to_be32(CIP_EOH
| CIP_FMT_AM
| AMDTP_FDF_AM824
|
666 (s
->sfc
<< CIP_FDF_SHIFT
) | syt
);
669 pcm
= ACCESS_ONCE(s
->pcm
);
671 s
->transfer_samples(s
, pcm
, buffer
, data_blocks
);
673 write_pcm_silence(s
, buffer
, data_blocks
);
675 write_midi_messages(s
, buffer
, data_blocks
);
677 s
->data_block_counter
= (s
->data_block_counter
+ data_blocks
) & 0xff;
679 payload_length
= 8 + data_blocks
* 4 * s
->data_block_quadlets
;
680 if (queue_out_packet(s
, payload_length
, false) < 0)
684 update_pcm_pointers(s
, pcm
, data_blocks
);
686 /* No need to return the number of handled data blocks. */
690 static int handle_in_packet(struct amdtp_stream
*s
,
691 unsigned int payload_quadlets
, __be32
*buffer
,
692 unsigned int *data_blocks
)
695 unsigned int data_block_quadlets
, data_block_counter
, dbc_interval
;
696 struct snd_pcm_substream
*pcm
= NULL
;
699 cip_header
[0] = be32_to_cpu(buffer
[0]);
700 cip_header
[1] = be32_to_cpu(buffer
[1]);
703 * This module supports 'Two-quadlet CIP header with SYT field'.
704 * For convenience, also check FMT field is AM824 or not.
706 if (((cip_header
[0] & CIP_EOH_MASK
) == CIP_EOH
) ||
707 ((cip_header
[1] & CIP_EOH_MASK
) != CIP_EOH
) ||
708 ((cip_header
[1] & CIP_FMT_MASK
) != CIP_FMT_AM
)) {
709 dev_info_ratelimited(&s
->unit
->device
,
710 "Invalid CIP header for AMDTP: %08X:%08X\n",
711 cip_header
[0], cip_header
[1]);
716 /* Calculate data blocks */
717 if (payload_quadlets
< 3 ||
718 ((cip_header
[1] & CIP_FDF_MASK
) ==
719 (AMDTP_FDF_NO_DATA
<< CIP_FDF_SHIFT
))) {
722 data_block_quadlets
=
723 (cip_header
[0] & CIP_DBS_MASK
) >> CIP_DBS_SHIFT
;
724 /* avoid division by zero */
725 if (data_block_quadlets
== 0) {
726 dev_err(&s
->unit
->device
,
727 "Detect invalid value in dbs field: %08X\n",
731 if (s
->flags
& CIP_WRONG_DBS
)
732 data_block_quadlets
= s
->data_block_quadlets
;
734 *data_blocks
= (payload_quadlets
- 2) / data_block_quadlets
;
737 /* Check data block counter continuity */
738 data_block_counter
= cip_header
[0] & CIP_DBC_MASK
;
739 if (*data_blocks
== 0 && (s
->flags
& CIP_EMPTY_HAS_WRONG_DBC
) &&
740 s
->data_block_counter
!= UINT_MAX
)
741 data_block_counter
= s
->data_block_counter
;
743 if (((s
->flags
& CIP_SKIP_DBC_ZERO_CHECK
) && data_block_counter
== 0) ||
744 (s
->data_block_counter
== UINT_MAX
)) {
746 } else if (!(s
->flags
& CIP_DBC_IS_END_EVENT
)) {
747 lost
= data_block_counter
!= s
->data_block_counter
;
749 if ((*data_blocks
> 0) && (s
->tx_dbc_interval
> 0))
750 dbc_interval
= s
->tx_dbc_interval
;
752 dbc_interval
= *data_blocks
;
754 lost
= data_block_counter
!=
755 ((s
->data_block_counter
+ dbc_interval
) & 0xff);
759 dev_err(&s
->unit
->device
,
760 "Detect discontinuity of CIP: %02X %02X\n",
761 s
->data_block_counter
, data_block_counter
);
765 if (*data_blocks
> 0) {
768 pcm
= ACCESS_ONCE(s
->pcm
);
770 s
->transfer_samples(s
, pcm
, buffer
, *data_blocks
);
773 read_midi_messages(s
, buffer
, *data_blocks
);
776 if (s
->flags
& CIP_DBC_IS_END_EVENT
)
777 s
->data_block_counter
= data_block_counter
;
779 s
->data_block_counter
=
780 (data_block_counter
+ *data_blocks
) & 0xff;
782 if (queue_in_packet(s
) < 0)
786 update_pcm_pointers(s
, pcm
, *data_blocks
);
791 static void out_stream_callback(struct fw_iso_context
*context
, u32 cycle
,
792 size_t header_length
, void *header
,
795 struct amdtp_stream
*s
= private_data
;
796 unsigned int i
, syt
, packets
= header_length
/ 4;
797 unsigned int data_blocks
;
799 if (s
->packet_index
< 0)
803 * Compute the cycle of the last queued packet.
804 * (We need only the four lowest bits for the SYT, so we can ignore
805 * that bits 0-11 must wrap around at 3072.)
807 cycle
+= QUEUE_LENGTH
- packets
;
809 for (i
= 0; i
< packets
; ++i
) {
810 syt
= calculate_syt(s
, ++cycle
);
811 data_blocks
= calculate_data_blocks(s
, syt
);
813 if (handle_out_packet(s
, data_blocks
, syt
) < 0) {
814 s
->packet_index
= -1;
815 amdtp_stream_pcm_abort(s
);
820 fw_iso_context_queue_flush(s
->context
);
823 static void in_stream_callback(struct fw_iso_context
*context
, u32 cycle
,
824 size_t header_length
, void *header
,
827 struct amdtp_stream
*s
= private_data
;
828 unsigned int p
, syt
, packets
;
829 unsigned int payload_quadlets
, max_payload_quadlets
;
830 unsigned int data_blocks
;
831 __be32
*buffer
, *headers
= header
;
833 if (s
->packet_index
< 0)
836 /* The number of packets in buffer */
837 packets
= header_length
/ IN_PACKET_HEADER_SIZE
;
839 /* For buffer-over-run prevention. */
840 max_payload_quadlets
= amdtp_stream_get_max_payload(s
) / 4;
842 for (p
= 0; p
< packets
; p
++) {
843 buffer
= s
->buffer
.packets
[s
->packet_index
].buffer
;
845 /* The number of quadlets in this packet */
847 (be32_to_cpu(headers
[p
]) >> ISO_DATA_LENGTH_SHIFT
) / 4;
848 if (payload_quadlets
> max_payload_quadlets
) {
849 dev_err(&s
->unit
->device
,
850 "Detect jumbo payload: %02x %02x\n",
851 payload_quadlets
, max_payload_quadlets
);
852 s
->packet_index
= -1;
856 if (handle_in_packet(s
, payload_quadlets
, buffer
,
858 s
->packet_index
= -1;
862 /* Process sync slave stream */
863 if (s
->sync_slave
&& s
->sync_slave
->callbacked
) {
864 syt
= be32_to_cpu(buffer
[1]) & CIP_SYT_MASK
;
865 if (handle_out_packet(s
->sync_slave
,
866 data_blocks
, syt
) < 0) {
867 s
->packet_index
= -1;
873 /* Queueing error or detecting discontinuity */
874 if (s
->packet_index
< 0) {
875 amdtp_stream_pcm_abort(s
);
877 /* Abort sync slave. */
879 s
->sync_slave
->packet_index
= -1;
880 amdtp_stream_pcm_abort(s
->sync_slave
);
885 /* when sync to device, flush the packets for slave stream */
886 if (s
->sync_slave
&& s
->sync_slave
->callbacked
)
887 fw_iso_context_queue_flush(s
->sync_slave
->context
);
889 fw_iso_context_queue_flush(s
->context
);
892 /* processing is done by master callback */
893 static void slave_stream_callback(struct fw_iso_context
*context
, u32 cycle
,
894 size_t header_length
, void *header
,
900 /* this is executed one time */
901 static void amdtp_stream_first_callback(struct fw_iso_context
*context
,
902 u32 cycle
, size_t header_length
,
903 void *header
, void *private_data
)
905 struct amdtp_stream
*s
= private_data
;
908 * For in-stream, first packet has come.
909 * For out-stream, prepared to transmit first packet
911 s
->callbacked
= true;
912 wake_up(&s
->callback_wait
);
914 if (s
->direction
== AMDTP_IN_STREAM
)
915 context
->callback
.sc
= in_stream_callback
;
916 else if (s
->flags
& CIP_SYNC_TO_DEVICE
)
917 context
->callback
.sc
= slave_stream_callback
;
919 context
->callback
.sc
= out_stream_callback
;
921 context
->callback
.sc(context
, cycle
, header_length
, header
, s
);
925 * amdtp_stream_start - start transferring packets
926 * @s: the AMDTP stream to start
927 * @channel: the isochronous channel on the bus
928 * @speed: firewire speed code
930 * The stream cannot be started until it has been configured with
931 * amdtp_stream_set_parameters() and it must be started before any PCM or MIDI
932 * device can be started.
934 int amdtp_stream_start(struct amdtp_stream
*s
, int channel
, int speed
)
936 static const struct {
937 unsigned int data_block
;
938 unsigned int syt_offset
;
939 } initial_state
[] = {
940 [CIP_SFC_32000
] = { 4, 3072 },
941 [CIP_SFC_48000
] = { 6, 1024 },
942 [CIP_SFC_96000
] = { 12, 1024 },
943 [CIP_SFC_192000
] = { 24, 1024 },
944 [CIP_SFC_44100
] = { 0, 67 },
945 [CIP_SFC_88200
] = { 0, 67 },
946 [CIP_SFC_176400
] = { 0, 67 },
948 unsigned int header_size
;
949 enum dma_data_direction dir
;
952 mutex_lock(&s
->mutex
);
954 if (WARN_ON(amdtp_stream_running(s
) ||
955 (s
->data_block_quadlets
< 1))) {
960 if (s
->direction
== AMDTP_IN_STREAM
&&
961 s
->flags
& CIP_SKIP_INIT_DBC_CHECK
)
962 s
->data_block_counter
= UINT_MAX
;
964 s
->data_block_counter
= 0;
965 s
->data_block_state
= initial_state
[s
->sfc
].data_block
;
966 s
->syt_offset_state
= initial_state
[s
->sfc
].syt_offset
;
967 s
->last_syt_offset
= TICKS_PER_CYCLE
;
969 /* initialize packet buffer */
970 if (s
->direction
== AMDTP_IN_STREAM
) {
971 dir
= DMA_FROM_DEVICE
;
972 type
= FW_ISO_CONTEXT_RECEIVE
;
973 header_size
= IN_PACKET_HEADER_SIZE
;
976 type
= FW_ISO_CONTEXT_TRANSMIT
;
977 header_size
= OUT_PACKET_HEADER_SIZE
;
979 err
= iso_packets_buffer_init(&s
->buffer
, s
->unit
, QUEUE_LENGTH
,
980 amdtp_stream_get_max_payload(s
), dir
);
984 s
->context
= fw_iso_context_create(fw_parent_device(s
->unit
)->card
,
985 type
, channel
, speed
, header_size
,
986 amdtp_stream_first_callback
, s
);
987 if (IS_ERR(s
->context
)) {
988 err
= PTR_ERR(s
->context
);
990 dev_err(&s
->unit
->device
,
991 "no free stream on this controller\n");
995 amdtp_stream_update(s
);
999 if (s
->direction
== AMDTP_IN_STREAM
)
1000 err
= queue_in_packet(s
);
1002 err
= queue_out_packet(s
, 0, true);
1005 } while (s
->packet_index
> 0);
1007 /* NOTE: TAG1 matches CIP. This just affects in stream. */
1008 tag
= FW_ISO_CONTEXT_MATCH_TAG1
;
1009 if (s
->flags
& CIP_EMPTY_WITH_TAG0
)
1010 tag
|= FW_ISO_CONTEXT_MATCH_TAG0
;
1012 s
->callbacked
= false;
1013 err
= fw_iso_context_start(s
->context
, -1, 0, tag
);
1017 mutex_unlock(&s
->mutex
);
1022 fw_iso_context_destroy(s
->context
);
1023 s
->context
= ERR_PTR(-1);
1025 iso_packets_buffer_destroy(&s
->buffer
, s
->unit
);
1027 mutex_unlock(&s
->mutex
);
1031 EXPORT_SYMBOL(amdtp_stream_start
);
1034 * amdtp_stream_pcm_pointer - get the PCM buffer position
1035 * @s: the AMDTP stream that transports the PCM data
1037 * Returns the current buffer position, in frames.
1039 unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream
*s
)
1041 /* this optimization is allowed to be racy */
1042 if (s
->pointer_flush
&& amdtp_stream_running(s
))
1043 fw_iso_context_flush_completions(s
->context
);
1045 s
->pointer_flush
= true;
1047 return ACCESS_ONCE(s
->pcm_buffer_pointer
);
1049 EXPORT_SYMBOL(amdtp_stream_pcm_pointer
);
1052 * amdtp_stream_update - update the stream after a bus reset
1053 * @s: the AMDTP stream
1055 void amdtp_stream_update(struct amdtp_stream
*s
)
1058 ACCESS_ONCE(s
->source_node_id_field
) =
1059 (fw_parent_device(s
->unit
)->card
->node_id
<< CIP_SID_SHIFT
) &
1062 EXPORT_SYMBOL(amdtp_stream_update
);
1065 * amdtp_stream_stop - stop sending packets
1066 * @s: the AMDTP stream to stop
1068 * All PCM and MIDI devices of the stream must be stopped before the stream
1069 * itself can be stopped.
1071 void amdtp_stream_stop(struct amdtp_stream
*s
)
1073 mutex_lock(&s
->mutex
);
1075 if (!amdtp_stream_running(s
)) {
1076 mutex_unlock(&s
->mutex
);
1080 tasklet_kill(&s
->period_tasklet
);
1081 fw_iso_context_stop(s
->context
);
1082 fw_iso_context_destroy(s
->context
);
1083 s
->context
= ERR_PTR(-1);
1084 iso_packets_buffer_destroy(&s
->buffer
, s
->unit
);
1086 s
->callbacked
= false;
1088 mutex_unlock(&s
->mutex
);
1090 EXPORT_SYMBOL(amdtp_stream_stop
);
1093 * amdtp_stream_pcm_abort - abort the running PCM device
1094 * @s: the AMDTP stream about to be stopped
1096 * If the isochronous stream needs to be stopped asynchronously, call this
1097 * function first to stop the PCM device.
1099 void amdtp_stream_pcm_abort(struct amdtp_stream
*s
)
1101 struct snd_pcm_substream
*pcm
;
1103 pcm
= ACCESS_ONCE(s
->pcm
);
1105 snd_pcm_stop_xrun(pcm
);
1107 EXPORT_SYMBOL(amdtp_stream_pcm_abort
);