linux/sound/firewire/amdtp.c
Takashi Sakamoto 82755abfe8 ALSA: firewire-lib: fix wrong value for FDF field as an empty packet
This commit fix out of specification about the value of FDF field in out packet
with 'no data'. This affects blocking mode.

According to IEC 61883-6, there is two way to generate AMDTP packets include no
data in blocking mode.

Way 1. an empty packet defined in IEC 61883-1
 - Size of packet is 2 quadlets.
 - The value of FDF is sfc.
 - The packet includes only CIP headers

Way 2. a special non-empty packet defined in IEC 61883-6
 - Size of packet is following to blocking mode
 - The value of FDF is 0xff. This value is 'NO-DATA'. This means 'The receiver'
   must ignore all the data in a CIP with this FDF code'.
 - The packet includes dummy data.

But current implementation is a combination of them.
 - Size of packet is 2 (way 1)
 - FDF = 0xff (way 2)
This causes BeBoB chipset cannot sound.

This patch applies Way 1.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Cc: Acked-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-11-22 15:30:46 +01:00

709 lines
19 KiB
C

/*
* Audio and Music Data Transmission Protocol (IEC 61883-6) streams
* with Common Isochronous Packet (IEC 61883-1) headers
*
* Copyright (c) Clemens Ladisch <clemens@ladisch.de>
* Licensed under the terms of the GNU General Public License, version 2.
*/
#include <linux/device.h>
#include <linux/err.h>
#include <linux/firewire.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <sound/pcm.h>
#include "amdtp.h"
#define TICKS_PER_CYCLE 3072
#define CYCLES_PER_SECOND 8000
#define TICKS_PER_SECOND (TICKS_PER_CYCLE * CYCLES_PER_SECOND)
#define TRANSFER_DELAY_TICKS 0x2e00 /* 479.17 µs */
#define TAG_CIP 1
#define CIP_EOH (1u << 31)
#define CIP_FMT_AM (0x10 << 24)
#define AMDTP_FDF_AM824 (0 << 19)
#define AMDTP_FDF_SFC_SHIFT 16
/* TODO: make these configurable */
#define INTERRUPT_INTERVAL 16
#define QUEUE_LENGTH 48
static void pcm_period_tasklet(unsigned long data);
/**
* amdtp_out_stream_init - initialize an AMDTP output stream structure
* @s: the AMDTP output stream to initialize
* @unit: the target of the stream
* @flags: the packet transmission method to use
*/
int amdtp_out_stream_init(struct amdtp_out_stream *s, struct fw_unit *unit,
enum cip_out_flags flags)
{
s->unit = fw_unit_get(unit);
s->flags = flags;
s->context = ERR_PTR(-1);
mutex_init(&s->mutex);
tasklet_init(&s->period_tasklet, pcm_period_tasklet, (unsigned long)s);
s->packet_index = 0;
return 0;
}
EXPORT_SYMBOL(amdtp_out_stream_init);
/**
* amdtp_out_stream_destroy - free stream resources
* @s: the AMDTP output stream to destroy
*/
void amdtp_out_stream_destroy(struct amdtp_out_stream *s)
{
WARN_ON(amdtp_out_stream_running(s));
mutex_destroy(&s->mutex);
fw_unit_put(s->unit);
}
EXPORT_SYMBOL(amdtp_out_stream_destroy);
const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT] = {
[CIP_SFC_32000] = 8,
[CIP_SFC_44100] = 8,
[CIP_SFC_48000] = 8,
[CIP_SFC_88200] = 16,
[CIP_SFC_96000] = 16,
[CIP_SFC_176400] = 32,
[CIP_SFC_192000] = 32,
};
EXPORT_SYMBOL(amdtp_syt_intervals);
/**
* amdtp_out_stream_set_parameters - set stream parameters
* @s: the AMDTP output stream to configure
* @rate: the sample rate
* @pcm_channels: the number of PCM samples in each data block, to be encoded
* as AM824 multi-bit linear audio
* @midi_ports: the number of MIDI ports (i.e., MPX-MIDI Data Channels)
*
* The parameters must be set before the stream is started, and must not be
* changed while the stream is running.
*/
void amdtp_out_stream_set_parameters(struct amdtp_out_stream *s,
unsigned int rate,
unsigned int pcm_channels,
unsigned int midi_ports)
{
static const unsigned int rates[] = {
[CIP_SFC_32000] = 32000,
[CIP_SFC_44100] = 44100,
[CIP_SFC_48000] = 48000,
[CIP_SFC_88200] = 88200,
[CIP_SFC_96000] = 96000,
[CIP_SFC_176400] = 176400,
[CIP_SFC_192000] = 192000,
};
unsigned int sfc;
if (WARN_ON(amdtp_out_stream_running(s)))
return;
for (sfc = 0; sfc < CIP_SFC_COUNT; ++sfc)
if (rates[sfc] == rate)
goto sfc_found;
WARN_ON(1);
return;
sfc_found:
s->dual_wire = (s->flags & CIP_HI_DUALWIRE) && sfc > CIP_SFC_96000;
if (s->dual_wire) {
sfc -= 2;
rate /= 2;
pcm_channels *= 2;
}
s->sfc = sfc;
s->data_block_quadlets = pcm_channels + DIV_ROUND_UP(midi_ports, 8);
s->pcm_channels = pcm_channels;
s->midi_ports = midi_ports;
s->syt_interval = amdtp_syt_intervals[sfc];
/* default buffering in the device */
s->transfer_delay = TRANSFER_DELAY_TICKS - TICKS_PER_CYCLE;
if (s->flags & CIP_BLOCKING)
/* additional buffering needed to adjust for no-data packets */
s->transfer_delay += TICKS_PER_SECOND * s->syt_interval / rate;
}
EXPORT_SYMBOL(amdtp_out_stream_set_parameters);
/**
* amdtp_out_stream_get_max_payload - get the stream's packet size
* @s: the AMDTP output stream
*
* This function must not be called before the stream has been configured
* with amdtp_out_stream_set_parameters().
*/
unsigned int amdtp_out_stream_get_max_payload(struct amdtp_out_stream *s)
{
return 8 + s->syt_interval * s->data_block_quadlets * 4;
}
EXPORT_SYMBOL(amdtp_out_stream_get_max_payload);
static void amdtp_write_s16(struct amdtp_out_stream *s,
struct snd_pcm_substream *pcm,
__be32 *buffer, unsigned int frames);
static void amdtp_write_s32(struct amdtp_out_stream *s,
struct snd_pcm_substream *pcm,
__be32 *buffer, unsigned int frames);
static void amdtp_write_s16_dualwire(struct amdtp_out_stream *s,
struct snd_pcm_substream *pcm,
__be32 *buffer, unsigned int frames);
static void amdtp_write_s32_dualwire(struct amdtp_out_stream *s,
struct snd_pcm_substream *pcm,
__be32 *buffer, unsigned int frames);
/**
* amdtp_out_stream_set_pcm_format - set the PCM format
* @s: the AMDTP output stream to configure
* @format: the format of the ALSA PCM device
*
* The sample format must be set after the other paramters (rate/PCM channels/
* MIDI) and before the stream is started, and must not be changed while the
* stream is running.
*/
void amdtp_out_stream_set_pcm_format(struct amdtp_out_stream *s,
snd_pcm_format_t format)
{
if (WARN_ON(amdtp_out_stream_running(s)))
return;
switch (format) {
default:
WARN_ON(1);
/* fall through */
case SNDRV_PCM_FORMAT_S16:
if (s->dual_wire)
s->transfer_samples = amdtp_write_s16_dualwire;
else
s->transfer_samples = amdtp_write_s16;
break;
case SNDRV_PCM_FORMAT_S32:
if (s->dual_wire)
s->transfer_samples = amdtp_write_s32_dualwire;
else
s->transfer_samples = amdtp_write_s32;
break;
}
}
EXPORT_SYMBOL(amdtp_out_stream_set_pcm_format);
/**
* amdtp_out_stream_pcm_prepare - prepare PCM device for running
* @s: the AMDTP output stream
*
* This function should be called from the PCM device's .prepare callback.
*/
void amdtp_out_stream_pcm_prepare(struct amdtp_out_stream *s)
{
tasklet_kill(&s->period_tasklet);
s->pcm_buffer_pointer = 0;
s->pcm_period_pointer = 0;
s->pointer_flush = true;
}
EXPORT_SYMBOL(amdtp_out_stream_pcm_prepare);
static unsigned int calculate_data_blocks(struct amdtp_out_stream *s)
{
unsigned int phase, data_blocks;
if (!cip_sfc_is_base_44100(s->sfc)) {
/* Sample_rate / 8000 is an integer, and precomputed. */
data_blocks = s->data_block_state;
} else {
phase = s->data_block_state;
/*
* This calculates the number of data blocks per packet so that
* 1) the overall rate is correct and exactly synchronized to
* the bus clock, and
* 2) packets with a rounded-up number of blocks occur as early
* as possible in the sequence (to prevent underruns of the
* device's buffer).
*/
if (s->sfc == CIP_SFC_44100)
/* 6 6 5 6 5 6 5 ... */
data_blocks = 5 + ((phase & 1) ^
(phase == 0 || phase >= 40));
else
/* 12 11 11 11 11 ... or 23 22 22 22 22 ... */
data_blocks = 11 * (s->sfc >> 1) + (phase == 0);
if (++phase >= (80 >> (s->sfc >> 1)))
phase = 0;
s->data_block_state = phase;
}
return data_blocks;
}
static unsigned int calculate_syt(struct amdtp_out_stream *s,
unsigned int cycle)
{
unsigned int syt_offset, phase, index, syt;
if (s->last_syt_offset < TICKS_PER_CYCLE) {
if (!cip_sfc_is_base_44100(s->sfc))
syt_offset = s->last_syt_offset + s->syt_offset_state;
else {
/*
* The time, in ticks, of the n'th SYT_INTERVAL sample is:
* n * SYT_INTERVAL * 24576000 / sample_rate
* Modulo TICKS_PER_CYCLE, the difference between successive
* elements is about 1386.23. Rounding the results of this
* formula to the SYT precision results in a sequence of
* differences that begins with:
* 1386 1386 1387 1386 1386 1386 1387 1386 1386 1386 1387 ...
* This code generates _exactly_ the same sequence.
*/
phase = s->syt_offset_state;
index = phase % 13;
syt_offset = s->last_syt_offset;
syt_offset += 1386 + ((index && !(index & 3)) ||
phase == 146);
if (++phase >= 147)
phase = 0;
s->syt_offset_state = phase;
}
} else
syt_offset = s->last_syt_offset - TICKS_PER_CYCLE;
s->last_syt_offset = syt_offset;
if (syt_offset < TICKS_PER_CYCLE) {
syt_offset += s->transfer_delay;
syt = (cycle + syt_offset / TICKS_PER_CYCLE) << 12;
syt += syt_offset % TICKS_PER_CYCLE;
return syt & 0xffff;
} else {
return 0xffff; /* no info */
}
}
static void amdtp_write_s32(struct amdtp_out_stream *s,
struct snd_pcm_substream *pcm,
__be32 *buffer, unsigned int frames)
{
struct snd_pcm_runtime *runtime = pcm->runtime;
unsigned int channels, remaining_frames, frame_step, i, c;
const u32 *src;
channels = s->pcm_channels;
src = (void *)runtime->dma_area +
frames_to_bytes(runtime, s->pcm_buffer_pointer);
remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
frame_step = s->data_block_quadlets - channels;
for (i = 0; i < frames; ++i) {
for (c = 0; c < channels; ++c) {
*buffer = cpu_to_be32((*src >> 8) | 0x40000000);
src++;
buffer++;
}
buffer += frame_step;
if (--remaining_frames == 0)
src = (void *)runtime->dma_area;
}
}
static void amdtp_write_s16(struct amdtp_out_stream *s,
struct snd_pcm_substream *pcm,
__be32 *buffer, unsigned int frames)
{
struct snd_pcm_runtime *runtime = pcm->runtime;
unsigned int channels, remaining_frames, frame_step, i, c;
const u16 *src;
channels = s->pcm_channels;
src = (void *)runtime->dma_area +
frames_to_bytes(runtime, s->pcm_buffer_pointer);
remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
frame_step = s->data_block_quadlets - channels;
for (i = 0; i < frames; ++i) {
for (c = 0; c < channels; ++c) {
*buffer = cpu_to_be32((*src << 8) | 0x40000000);
src++;
buffer++;
}
buffer += frame_step;
if (--remaining_frames == 0)
src = (void *)runtime->dma_area;
}
}
static void amdtp_write_s32_dualwire(struct amdtp_out_stream *s,
struct snd_pcm_substream *pcm,
__be32 *buffer, unsigned int frames)
{
struct snd_pcm_runtime *runtime = pcm->runtime;
unsigned int channels, frame_adjust_1, frame_adjust_2, i, c;
const u32 *src;
channels = s->pcm_channels;
src = (void *)runtime->dma_area +
s->pcm_buffer_pointer * (runtime->frame_bits / 8);
frame_adjust_1 = channels - 1;
frame_adjust_2 = 1 - (s->data_block_quadlets - channels);
channels /= 2;
for (i = 0; i < frames; ++i) {
for (c = 0; c < channels; ++c) {
*buffer = cpu_to_be32((*src >> 8) | 0x40000000);
src++;
buffer += 2;
}
buffer -= frame_adjust_1;
for (c = 0; c < channels; ++c) {
*buffer = cpu_to_be32((*src >> 8) | 0x40000000);
src++;
buffer += 2;
}
buffer -= frame_adjust_2;
}
}
static void amdtp_write_s16_dualwire(struct amdtp_out_stream *s,
struct snd_pcm_substream *pcm,
__be32 *buffer, unsigned int frames)
{
struct snd_pcm_runtime *runtime = pcm->runtime;
unsigned int channels, frame_adjust_1, frame_adjust_2, i, c;
const u16 *src;
channels = s->pcm_channels;
src = (void *)runtime->dma_area +
s->pcm_buffer_pointer * (runtime->frame_bits / 8);
frame_adjust_1 = channels - 1;
frame_adjust_2 = 1 - (s->data_block_quadlets - channels);
channels /= 2;
for (i = 0; i < frames; ++i) {
for (c = 0; c < channels; ++c) {
*buffer = cpu_to_be32((*src << 8) | 0x40000000);
src++;
buffer += 2;
}
buffer -= frame_adjust_1;
for (c = 0; c < channels; ++c) {
*buffer = cpu_to_be32((*src << 8) | 0x40000000);
src++;
buffer += 2;
}
buffer -= frame_adjust_2;
}
}
static void amdtp_fill_pcm_silence(struct amdtp_out_stream *s,
__be32 *buffer, unsigned int frames)
{
unsigned int i, c;
for (i = 0; i < frames; ++i) {
for (c = 0; c < s->pcm_channels; ++c)
buffer[c] = cpu_to_be32(0x40000000);
buffer += s->data_block_quadlets;
}
}
static void amdtp_fill_midi(struct amdtp_out_stream *s,
__be32 *buffer, unsigned int frames)
{
unsigned int i;
for (i = 0; i < frames; ++i)
buffer[s->pcm_channels + i * s->data_block_quadlets] =
cpu_to_be32(0x80000000);
}
static void queue_out_packet(struct amdtp_out_stream *s, unsigned int cycle)
{
__be32 *buffer;
unsigned int index, data_blocks, syt, ptr;
struct snd_pcm_substream *pcm;
struct fw_iso_packet packet;
int err;
if (s->packet_index < 0)
return;
index = s->packet_index;
/* this module generate empty packet for 'no data' */
syt = calculate_syt(s, cycle);
if (!(s->flags & CIP_BLOCKING))
data_blocks = calculate_data_blocks(s);
else if (syt != 0xffff)
data_blocks = s->syt_interval;
else
data_blocks = 0;
buffer = s->buffer.packets[index].buffer;
buffer[0] = cpu_to_be32(ACCESS_ONCE(s->source_node_id_field) |
(s->data_block_quadlets << 16) |
s->data_block_counter);
buffer[1] = cpu_to_be32(CIP_EOH | CIP_FMT_AM | AMDTP_FDF_AM824 |
(s->sfc << AMDTP_FDF_SFC_SHIFT) | syt);
buffer += 2;
pcm = ACCESS_ONCE(s->pcm);
if (pcm)
s->transfer_samples(s, pcm, buffer, data_blocks);
else
amdtp_fill_pcm_silence(s, buffer, data_blocks);
if (s->midi_ports)
amdtp_fill_midi(s, buffer, data_blocks);
s->data_block_counter = (s->data_block_counter + data_blocks) & 0xff;
packet.payload_length = 8 + data_blocks * 4 * s->data_block_quadlets;
packet.interrupt = IS_ALIGNED(index + 1, INTERRUPT_INTERVAL);
packet.skip = 0;
packet.tag = TAG_CIP;
packet.sy = 0;
packet.header_length = 0;
err = fw_iso_context_queue(s->context, &packet, &s->buffer.iso_buffer,
s->buffer.packets[index].offset);
if (err < 0) {
dev_err(&s->unit->device, "queueing error: %d\n", err);
s->packet_index = -1;
amdtp_out_stream_pcm_abort(s);
return;
}
if (++index >= QUEUE_LENGTH)
index = 0;
s->packet_index = index;
if (pcm) {
if (s->dual_wire)
data_blocks *= 2;
ptr = s->pcm_buffer_pointer + data_blocks;
if (ptr >= pcm->runtime->buffer_size)
ptr -= pcm->runtime->buffer_size;
ACCESS_ONCE(s->pcm_buffer_pointer) = ptr;
s->pcm_period_pointer += data_blocks;
if (s->pcm_period_pointer >= pcm->runtime->period_size) {
s->pcm_period_pointer -= pcm->runtime->period_size;
s->pointer_flush = false;
tasklet_hi_schedule(&s->period_tasklet);
}
}
}
static void pcm_period_tasklet(unsigned long data)
{
struct amdtp_out_stream *s = (void *)data;
struct snd_pcm_substream *pcm = ACCESS_ONCE(s->pcm);
if (pcm)
snd_pcm_period_elapsed(pcm);
}
static void out_packet_callback(struct fw_iso_context *context, u32 cycle,
size_t header_length, void *header, void *data)
{
struct amdtp_out_stream *s = data;
unsigned int i, packets = header_length / 4;
/*
* Compute the cycle of the last queued packet.
* (We need only the four lowest bits for the SYT, so we can ignore
* that bits 0-11 must wrap around at 3072.)
*/
cycle += QUEUE_LENGTH - packets;
for (i = 0; i < packets; ++i)
queue_out_packet(s, ++cycle);
fw_iso_context_queue_flush(s->context);
}
static int queue_initial_skip_packets(struct amdtp_out_stream *s)
{
struct fw_iso_packet skip_packet = {
.skip = 1,
};
unsigned int i;
int err;
for (i = 0; i < QUEUE_LENGTH; ++i) {
skip_packet.interrupt = IS_ALIGNED(s->packet_index + 1,
INTERRUPT_INTERVAL);
err = fw_iso_context_queue(s->context, &skip_packet, NULL, 0);
if (err < 0)
return err;
if (++s->packet_index >= QUEUE_LENGTH)
s->packet_index = 0;
}
return 0;
}
/**
* amdtp_out_stream_start - start sending packets
* @s: the AMDTP output stream to start
* @channel: the isochronous channel on the bus
* @speed: firewire speed code
*
* The stream cannot be started until it has been configured with
* amdtp_out_stream_set_parameters() and amdtp_out_stream_set_pcm_format(),
* and it must be started before any PCM or MIDI device can be started.
*/
int amdtp_out_stream_start(struct amdtp_out_stream *s, int channel, int speed)
{
static const struct {
unsigned int data_block;
unsigned int syt_offset;
} initial_state[] = {
[CIP_SFC_32000] = { 4, 3072 },
[CIP_SFC_48000] = { 6, 1024 },
[CIP_SFC_96000] = { 12, 1024 },
[CIP_SFC_192000] = { 24, 1024 },
[CIP_SFC_44100] = { 0, 67 },
[CIP_SFC_88200] = { 0, 67 },
[CIP_SFC_176400] = { 0, 67 },
};
int err;
mutex_lock(&s->mutex);
if (WARN_ON(amdtp_out_stream_running(s) ||
(!s->pcm_channels && !s->midi_ports))) {
err = -EBADFD;
goto err_unlock;
}
s->data_block_state = initial_state[s->sfc].data_block;
s->syt_offset_state = initial_state[s->sfc].syt_offset;
s->last_syt_offset = TICKS_PER_CYCLE;
err = iso_packets_buffer_init(&s->buffer, s->unit, QUEUE_LENGTH,
amdtp_out_stream_get_max_payload(s),
DMA_TO_DEVICE);
if (err < 0)
goto err_unlock;
s->context = fw_iso_context_create(fw_parent_device(s->unit)->card,
FW_ISO_CONTEXT_TRANSMIT,
channel, speed, 0,
out_packet_callback, s);
if (IS_ERR(s->context)) {
err = PTR_ERR(s->context);
if (err == -EBUSY)
dev_err(&s->unit->device,
"no free output stream on this controller\n");
goto err_buffer;
}
amdtp_out_stream_update(s);
s->packet_index = 0;
s->data_block_counter = 0;
err = queue_initial_skip_packets(s);
if (err < 0)
goto err_context;
err = fw_iso_context_start(s->context, -1, 0, 0);
if (err < 0)
goto err_context;
mutex_unlock(&s->mutex);
return 0;
err_context:
fw_iso_context_destroy(s->context);
s->context = ERR_PTR(-1);
err_buffer:
iso_packets_buffer_destroy(&s->buffer, s->unit);
err_unlock:
mutex_unlock(&s->mutex);
return err;
}
EXPORT_SYMBOL(amdtp_out_stream_start);
/**
* amdtp_out_stream_pcm_pointer - get the PCM buffer position
* @s: the AMDTP output stream that transports the PCM data
*
* Returns the current buffer position, in frames.
*/
unsigned long amdtp_out_stream_pcm_pointer(struct amdtp_out_stream *s)
{
/* this optimization is allowed to be racy */
if (s->pointer_flush)
fw_iso_context_flush_completions(s->context);
else
s->pointer_flush = true;
return ACCESS_ONCE(s->pcm_buffer_pointer);
}
EXPORT_SYMBOL(amdtp_out_stream_pcm_pointer);
/**
* amdtp_out_stream_update - update the stream after a bus reset
* @s: the AMDTP output stream
*/
void amdtp_out_stream_update(struct amdtp_out_stream *s)
{
ACCESS_ONCE(s->source_node_id_field) =
(fw_parent_device(s->unit)->card->node_id & 0x3f) << 24;
}
EXPORT_SYMBOL(amdtp_out_stream_update);
/**
* amdtp_out_stream_stop - stop sending packets
* @s: the AMDTP output stream to stop
*
* All PCM and MIDI devices of the stream must be stopped before the stream
* itself can be stopped.
*/
void amdtp_out_stream_stop(struct amdtp_out_stream *s)
{
mutex_lock(&s->mutex);
if (!amdtp_out_stream_running(s)) {
mutex_unlock(&s->mutex);
return;
}
tasklet_kill(&s->period_tasklet);
fw_iso_context_stop(s->context);
fw_iso_context_destroy(s->context);
s->context = ERR_PTR(-1);
iso_packets_buffer_destroy(&s->buffer, s->unit);
mutex_unlock(&s->mutex);
}
EXPORT_SYMBOL(amdtp_out_stream_stop);
/**
* amdtp_out_stream_pcm_abort - abort the running PCM device
* @s: the AMDTP stream about to be stopped
*
* If the isochronous stream needs to be stopped asynchronously, call this
* function first to stop the PCM device.
*/
void amdtp_out_stream_pcm_abort(struct amdtp_out_stream *s)
{
struct snd_pcm_substream *pcm;
pcm = ACCESS_ONCE(s->pcm);
if (pcm) {
snd_pcm_stream_lock_irq(pcm);
if (snd_pcm_running(pcm))
snd_pcm_stop(pcm, SNDRV_PCM_STATE_XRUN);
snd_pcm_stream_unlock_irq(pcm);
}
}
EXPORT_SYMBOL(amdtp_out_stream_pcm_abort);