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-rw-r--r--sound/firewire/amdtp.c1064
1 files changed, 1064 insertions, 0 deletions
diff --git a/sound/firewire/amdtp.c b/sound/firewire/amdtp.c
new file mode 100644
index 000000000..e061355f5
--- /dev/null
+++ b/sound/firewire/amdtp.c
@@ -0,0 +1,1064 @@
+/*
+ * 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 <linux/sched.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/rawmidi.h>
+#include "amdtp.h"
+
+#define TICKS_PER_CYCLE 3072
+#define CYCLES_PER_SECOND 8000
+#define TICKS_PER_SECOND (TICKS_PER_CYCLE * CYCLES_PER_SECOND)
+
+/*
+ * Nominally 3125 bytes/second, but the MIDI port's clock might be
+ * 1% too slow, and the bus clock 100 ppm too fast.
+ */
+#define MIDI_BYTES_PER_SECOND 3093
+
+/*
+ * Several devices look only at the first eight data blocks.
+ * In any case, this is more than enough for the MIDI data rate.
+ */
+#define MAX_MIDI_RX_BLOCKS 8
+
+#define TRANSFER_DELAY_TICKS 0x2e00 /* 479.17 microseconds */
+
+/* isochronous header parameters */
+#define ISO_DATA_LENGTH_SHIFT 16
+#define TAG_CIP 1
+
+/* common isochronous packet header parameters */
+#define CIP_EOH (1u << 31)
+#define CIP_EOH_MASK 0x80000000
+#define CIP_FMT_AM (0x10 << 24)
+#define CIP_FMT_MASK 0x3f000000
+#define CIP_SYT_MASK 0x0000ffff
+#define CIP_SYT_NO_INFO 0xffff
+#define CIP_FDF_MASK 0x00ff0000
+#define CIP_FDF_SFC_SHIFT 16
+
+/*
+ * Audio and Music transfer protocol specific parameters
+ * only "Clock-based rate control mode" is supported
+ */
+#define AMDTP_FDF_AM824 (0 << (CIP_FDF_SFC_SHIFT + 3))
+#define AMDTP_FDF_NO_DATA 0xff
+#define AMDTP_DBS_MASK 0x00ff0000
+#define AMDTP_DBS_SHIFT 16
+#define AMDTP_DBC_MASK 0x000000ff
+
+/* TODO: make these configurable */
+#define INTERRUPT_INTERVAL 16
+#define QUEUE_LENGTH 48
+
+#define IN_PACKET_HEADER_SIZE 4
+#define OUT_PACKET_HEADER_SIZE 0
+
+static void pcm_period_tasklet(unsigned long data);
+
+/**
+ * amdtp_stream_init - initialize an AMDTP stream structure
+ * @s: the AMDTP stream to initialize
+ * @unit: the target of the stream
+ * @dir: the direction of stream
+ * @flags: the packet transmission method to use
+ */
+int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
+ enum amdtp_stream_direction dir, enum cip_flags flags)
+{
+ s->unit = unit;
+ s->direction = dir;
+ 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;
+
+ init_waitqueue_head(&s->callback_wait);
+ s->callbacked = false;
+ s->sync_slave = NULL;
+
+ return 0;
+}
+EXPORT_SYMBOL(amdtp_stream_init);
+
+/**
+ * amdtp_stream_destroy - free stream resources
+ * @s: the AMDTP stream to destroy
+ */
+void amdtp_stream_destroy(struct amdtp_stream *s)
+{
+ WARN_ON(amdtp_stream_running(s));
+ mutex_destroy(&s->mutex);
+}
+EXPORT_SYMBOL(amdtp_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);
+
+const unsigned int amdtp_rate_table[CIP_SFC_COUNT] = {
+ [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,
+};
+EXPORT_SYMBOL(amdtp_rate_table);
+
+/**
+ * amdtp_stream_add_pcm_hw_constraints - add hw constraints for PCM substream
+ * @s: the AMDTP stream, which must be initialized.
+ * @runtime: the PCM substream runtime
+ */
+int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
+ struct snd_pcm_runtime *runtime)
+{
+ int err;
+
+ /* AM824 in IEC 61883-6 can deliver 24bit data */
+ err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);
+ if (err < 0)
+ goto end;
+
+ /*
+ * Currently firewire-lib processes 16 packets in one software
+ * interrupt callback. This equals to 2msec but actually the
+ * interval of the interrupts has a jitter.
+ * Additionally, even if adding a constraint to fit period size to
+ * 2msec, actual calculated frames per period doesn't equal to 2msec,
+ * depending on sampling rate.
+ * Anyway, the interval to call snd_pcm_period_elapsed() cannot 2msec.
+ * Here let us use 5msec for safe period interrupt.
+ */
+ err = snd_pcm_hw_constraint_minmax(runtime,
+ SNDRV_PCM_HW_PARAM_PERIOD_TIME,
+ 5000, UINT_MAX);
+ if (err < 0)
+ goto end;
+
+ /* Non-Blocking stream has no more constraints */
+ if (!(s->flags & CIP_BLOCKING))
+ goto end;
+
+ /*
+ * One AMDTP packet can include some frames. In blocking mode, the
+ * number equals to SYT_INTERVAL. So the number is 8, 16 or 32,
+ * depending on its sampling rate. For accurate period interrupt, it's
+ * preferrable to align period/buffer sizes to current SYT_INTERVAL.
+ *
+ * TODO: These constraints can be improved with proper rules.
+ * Currently apply LCM of SYT_INTERVALs.
+ */
+ err = snd_pcm_hw_constraint_step(runtime, 0,
+ SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 32);
+ if (err < 0)
+ goto end;
+ err = snd_pcm_hw_constraint_step(runtime, 0,
+ SNDRV_PCM_HW_PARAM_BUFFER_SIZE, 32);
+end:
+ return err;
+}
+EXPORT_SYMBOL(amdtp_stream_add_pcm_hw_constraints);
+
+/**
+ * amdtp_stream_set_parameters - set stream parameters
+ * @s: the AMDTP 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_stream_set_parameters(struct amdtp_stream *s,
+ unsigned int rate,
+ unsigned int pcm_channels,
+ unsigned int midi_ports)
+{
+ unsigned int i, sfc, midi_channels;
+
+ midi_channels = DIV_ROUND_UP(midi_ports, 8);
+
+ if (WARN_ON(amdtp_stream_running(s)) |
+ WARN_ON(pcm_channels > AMDTP_MAX_CHANNELS_FOR_PCM) |
+ WARN_ON(midi_channels > AMDTP_MAX_CHANNELS_FOR_MIDI))
+ return;
+
+ for (sfc = 0; sfc < ARRAY_SIZE(amdtp_rate_table); ++sfc)
+ if (amdtp_rate_table[sfc] == rate)
+ goto sfc_found;
+ WARN_ON(1);
+ return;
+
+sfc_found:
+ s->pcm_channels = pcm_channels;
+ s->sfc = sfc;
+ s->data_block_quadlets = s->pcm_channels + midi_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;
+
+ /* init the position map for PCM and MIDI channels */
+ for (i = 0; i < pcm_channels; i++)
+ s->pcm_positions[i] = i;
+ s->midi_position = s->pcm_channels;
+
+ /*
+ * We do not know the actual MIDI FIFO size of most devices. Just
+ * assume two bytes, i.e., one byte can be received over the bus while
+ * the previous one is transmitted over MIDI.
+ * (The value here is adjusted for midi_ratelimit_per_packet().)
+ */
+ s->midi_fifo_limit = rate - MIDI_BYTES_PER_SECOND * s->syt_interval + 1;
+}
+EXPORT_SYMBOL(amdtp_stream_set_parameters);
+
+/**
+ * amdtp_stream_get_max_payload - get the stream's packet size
+ * @s: the AMDTP stream
+ *
+ * This function must not be called before the stream has been configured
+ * with amdtp_stream_set_parameters().
+ */
+unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s)
+{
+ return 8 + s->syt_interval * s->data_block_quadlets * 4;
+}
+EXPORT_SYMBOL(amdtp_stream_get_max_payload);
+
+static void amdtp_write_s16(struct amdtp_stream *s,
+ struct snd_pcm_substream *pcm,
+ __be32 *buffer, unsigned int frames);
+static void amdtp_write_s32(struct amdtp_stream *s,
+ struct snd_pcm_substream *pcm,
+ __be32 *buffer, unsigned int frames);
+static void amdtp_read_s32(struct amdtp_stream *s,
+ struct snd_pcm_substream *pcm,
+ __be32 *buffer, unsigned int frames);
+
+/**
+ * amdtp_stream_set_pcm_format - set the PCM format
+ * @s: the AMDTP stream to configure
+ * @format: the format of the ALSA PCM device
+ *
+ * The sample format must be set after the other parameters (rate/PCM channels/
+ * MIDI) and before the stream is started, and must not be changed while the
+ * stream is running.
+ */
+void amdtp_stream_set_pcm_format(struct amdtp_stream *s,
+ snd_pcm_format_t format)
+{
+ if (WARN_ON(amdtp_stream_pcm_running(s)))
+ return;
+
+ switch (format) {
+ default:
+ WARN_ON(1);
+ /* fall through */
+ case SNDRV_PCM_FORMAT_S16:
+ if (s->direction == AMDTP_OUT_STREAM) {
+ s->transfer_samples = amdtp_write_s16;
+ break;
+ }
+ WARN_ON(1);
+ /* fall through */
+ case SNDRV_PCM_FORMAT_S32:
+ if (s->direction == AMDTP_OUT_STREAM)
+ s->transfer_samples = amdtp_write_s32;
+ else
+ s->transfer_samples = amdtp_read_s32;
+ break;
+ }
+}
+EXPORT_SYMBOL(amdtp_stream_set_pcm_format);
+
+/**
+ * amdtp_stream_pcm_prepare - prepare PCM device for running
+ * @s: the AMDTP stream
+ *
+ * This function should be called from the PCM device's .prepare callback.
+ */
+void amdtp_stream_pcm_prepare(struct amdtp_stream *s)
+{
+ tasklet_kill(&s->period_tasklet);
+ s->pcm_buffer_pointer = 0;
+ s->pcm_period_pointer = 0;
+ s->pointer_flush = true;
+}
+EXPORT_SYMBOL(amdtp_stream_pcm_prepare);
+
+static unsigned int calculate_data_blocks(struct amdtp_stream *s)
+{
+ unsigned int phase, data_blocks;
+
+ if (s->flags & CIP_BLOCKING)
+ data_blocks = s->syt_interval;
+ else 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_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 & CIP_SYT_MASK;
+ } else {
+ return CIP_SYT_NO_INFO;
+ }
+}
+
+static void amdtp_write_s32(struct amdtp_stream *s,
+ struct snd_pcm_substream *pcm,
+ __be32 *buffer, unsigned int frames)
+{
+ struct snd_pcm_runtime *runtime = pcm->runtime;
+ unsigned int channels, remaining_frames, 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;
+
+ for (i = 0; i < frames; ++i) {
+ for (c = 0; c < channels; ++c) {
+ buffer[s->pcm_positions[c]] =
+ cpu_to_be32((*src >> 8) | 0x40000000);
+ src++;
+ }
+ buffer += s->data_block_quadlets;
+ if (--remaining_frames == 0)
+ src = (void *)runtime->dma_area;
+ }
+}
+
+static void amdtp_write_s16(struct amdtp_stream *s,
+ struct snd_pcm_substream *pcm,
+ __be32 *buffer, unsigned int frames)
+{
+ struct snd_pcm_runtime *runtime = pcm->runtime;
+ unsigned int channels, remaining_frames, 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;
+
+ for (i = 0; i < frames; ++i) {
+ for (c = 0; c < channels; ++c) {
+ buffer[s->pcm_positions[c]] =
+ cpu_to_be32((*src << 8) | 0x42000000);
+ src++;
+ }
+ buffer += s->data_block_quadlets;
+ if (--remaining_frames == 0)
+ src = (void *)runtime->dma_area;
+ }
+}
+
+static void amdtp_read_s32(struct amdtp_stream *s,
+ struct snd_pcm_substream *pcm,
+ __be32 *buffer, unsigned int frames)
+{
+ struct snd_pcm_runtime *runtime = pcm->runtime;
+ unsigned int channels, remaining_frames, i, c;
+ u32 *dst;
+
+ channels = s->pcm_channels;
+ dst = (void *)runtime->dma_area +
+ frames_to_bytes(runtime, s->pcm_buffer_pointer);
+ remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
+
+ for (i = 0; i < frames; ++i) {
+ for (c = 0; c < channels; ++c) {
+ *dst = be32_to_cpu(buffer[s->pcm_positions[c]]) << 8;
+ dst++;
+ }
+ buffer += s->data_block_quadlets;
+ if (--remaining_frames == 0)
+ dst = (void *)runtime->dma_area;
+ }
+}
+
+static void amdtp_fill_pcm_silence(struct amdtp_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[s->pcm_positions[c]] = cpu_to_be32(0x40000000);
+ buffer += s->data_block_quadlets;
+ }
+}
+
+/*
+ * To avoid sending MIDI bytes at too high a rate, assume that the receiving
+ * device has a FIFO, and track how much it is filled. This values increases
+ * by one whenever we send one byte in a packet, but the FIFO empties at
+ * a constant rate independent of our packet rate. One packet has syt_interval
+ * samples, so the number of bytes that empty out of the FIFO, per packet(!),
+ * is MIDI_BYTES_PER_SECOND * syt_interval / sample_rate. To avoid storing
+ * fractional values, the values in midi_fifo_used[] are measured in bytes
+ * multiplied by the sample rate.
+ */
+static bool midi_ratelimit_per_packet(struct amdtp_stream *s, unsigned int port)
+{
+ int used;
+
+ used = s->midi_fifo_used[port];
+ if (used == 0) /* common shortcut */
+ return true;
+
+ used -= MIDI_BYTES_PER_SECOND * s->syt_interval;
+ used = max(used, 0);
+ s->midi_fifo_used[port] = used;
+
+ return used < s->midi_fifo_limit;
+}
+
+static void midi_rate_use_one_byte(struct amdtp_stream *s, unsigned int port)
+{
+ s->midi_fifo_used[port] += amdtp_rate_table[s->sfc];
+}
+
+static void amdtp_fill_midi(struct amdtp_stream *s,
+ __be32 *buffer, unsigned int frames)
+{
+ unsigned int f, port;
+ u8 *b;
+
+ for (f = 0; f < frames; f++) {
+ b = (u8 *)&buffer[s->midi_position];
+
+ port = (s->data_block_counter + f) % 8;
+ if (f < MAX_MIDI_RX_BLOCKS &&
+ midi_ratelimit_per_packet(s, port) &&
+ s->midi[port] != NULL &&
+ snd_rawmidi_transmit(s->midi[port], &b[1], 1) == 1) {
+ midi_rate_use_one_byte(s, port);
+ b[0] = 0x81;
+ } else {
+ b[0] = 0x80;
+ b[1] = 0;
+ }
+ b[2] = 0;
+ b[3] = 0;
+
+ buffer += s->data_block_quadlets;
+ }
+}
+
+static void amdtp_pull_midi(struct amdtp_stream *s,
+ __be32 *buffer, unsigned int frames)
+{
+ unsigned int f, port;
+ int len;
+ u8 *b;
+
+ for (f = 0; f < frames; f++) {
+ port = (s->data_block_counter + f) % 8;
+ b = (u8 *)&buffer[s->midi_position];
+
+ len = b[0] - 0x80;
+ if ((1 <= len) && (len <= 3) && (s->midi[port]))
+ snd_rawmidi_receive(s->midi[port], b + 1, len);
+
+ buffer += s->data_block_quadlets;
+ }
+}
+
+static void update_pcm_pointers(struct amdtp_stream *s,
+ struct snd_pcm_substream *pcm,
+ unsigned int frames)
+{
+ unsigned int ptr;
+
+ /*
+ * In IEC 61883-6, one data block represents one event. In ALSA, one
+ * event equals to one PCM frame. But Dice has a quirk to transfer
+ * two PCM frames in one data block.
+ */
+ if (s->double_pcm_frames)
+ frames *= 2;
+
+ ptr = s->pcm_buffer_pointer + frames;
+ if (ptr >= pcm->runtime->buffer_size)
+ ptr -= pcm->runtime->buffer_size;
+ ACCESS_ONCE(s->pcm_buffer_pointer) = ptr;
+
+ s->pcm_period_pointer += frames;
+ 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_stream *s = (void *)data;
+ struct snd_pcm_substream *pcm = ACCESS_ONCE(s->pcm);
+
+ if (pcm)
+ snd_pcm_period_elapsed(pcm);
+}
+
+static int queue_packet(struct amdtp_stream *s,
+ unsigned int header_length,
+ unsigned int payload_length, bool skip)
+{
+ struct fw_iso_packet p = {0};
+ int err = 0;
+
+ if (IS_ERR(s->context))
+ goto end;
+
+ p.interrupt = IS_ALIGNED(s->packet_index + 1, INTERRUPT_INTERVAL);
+ p.tag = TAG_CIP;
+ p.header_length = header_length;
+ p.payload_length = (!skip) ? payload_length : 0;
+ p.skip = skip;
+ err = fw_iso_context_queue(s->context, &p, &s->buffer.iso_buffer,
+ s->buffer.packets[s->packet_index].offset);
+ if (err < 0) {
+ dev_err(&s->unit->device, "queueing error: %d\n", err);
+ goto end;
+ }
+
+ if (++s->packet_index >= QUEUE_LENGTH)
+ s->packet_index = 0;
+end:
+ return err;
+}
+
+static inline int queue_out_packet(struct amdtp_stream *s,
+ unsigned int payload_length, bool skip)
+{
+ return queue_packet(s, OUT_PACKET_HEADER_SIZE,
+ payload_length, skip);
+}
+
+static inline int queue_in_packet(struct amdtp_stream *s)
+{
+ return queue_packet(s, IN_PACKET_HEADER_SIZE,
+ amdtp_stream_get_max_payload(s), false);
+}
+
+static void handle_out_packet(struct amdtp_stream *s, unsigned int syt)
+{
+ __be32 *buffer;
+ unsigned int data_blocks, payload_length;
+ struct snd_pcm_substream *pcm;
+
+ if (s->packet_index < 0)
+ return;
+
+ /* this module generate empty packet for 'no data' */
+ if (!(s->flags & CIP_BLOCKING) || (syt != CIP_SYT_NO_INFO))
+ data_blocks = calculate_data_blocks(s);
+ else
+ data_blocks = 0;
+
+ buffer = s->buffer.packets[s->packet_index].buffer;
+ buffer[0] = cpu_to_be32(ACCESS_ONCE(s->source_node_id_field) |
+ (s->data_block_quadlets << AMDTP_DBS_SHIFT) |
+ s->data_block_counter);
+ buffer[1] = cpu_to_be32(CIP_EOH | CIP_FMT_AM | AMDTP_FDF_AM824 |
+ (s->sfc << CIP_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;
+
+ payload_length = 8 + data_blocks * 4 * s->data_block_quadlets;
+ if (queue_out_packet(s, payload_length, false) < 0) {
+ s->packet_index = -1;
+ amdtp_stream_pcm_abort(s);
+ return;
+ }
+
+ if (pcm)
+ update_pcm_pointers(s, pcm, data_blocks);
+}
+
+static void handle_in_packet(struct amdtp_stream *s,
+ unsigned int payload_quadlets,
+ __be32 *buffer)
+{
+ u32 cip_header[2];
+ unsigned int data_blocks, data_block_quadlets, data_block_counter,
+ dbc_interval;
+ struct snd_pcm_substream *pcm = NULL;
+ bool lost;
+
+ cip_header[0] = be32_to_cpu(buffer[0]);
+ cip_header[1] = be32_to_cpu(buffer[1]);
+
+ /*
+ * This module supports 'Two-quadlet CIP header with SYT field'.
+ * For convenience, also check FMT field is AM824 or not.
+ */
+ if (((cip_header[0] & CIP_EOH_MASK) == CIP_EOH) ||
+ ((cip_header[1] & CIP_EOH_MASK) != CIP_EOH) ||
+ ((cip_header[1] & CIP_FMT_MASK) != CIP_FMT_AM)) {
+ dev_info_ratelimited(&s->unit->device,
+ "Invalid CIP header for AMDTP: %08X:%08X\n",
+ cip_header[0], cip_header[1]);
+ goto end;
+ }
+
+ /* Calculate data blocks */
+ if (payload_quadlets < 3 ||
+ ((cip_header[1] & CIP_FDF_MASK) ==
+ (AMDTP_FDF_NO_DATA << CIP_FDF_SFC_SHIFT))) {
+ data_blocks = 0;
+ } else {
+ data_block_quadlets =
+ (cip_header[0] & AMDTP_DBS_MASK) >> AMDTP_DBS_SHIFT;
+ /* avoid division by zero */
+ if (data_block_quadlets == 0) {
+ dev_info_ratelimited(&s->unit->device,
+ "Detect invalid value in dbs field: %08X\n",
+ cip_header[0]);
+ goto err;
+ }
+ if (s->flags & CIP_WRONG_DBS)
+ data_block_quadlets = s->data_block_quadlets;
+
+ data_blocks = (payload_quadlets - 2) / data_block_quadlets;
+ }
+
+ /* Check data block counter continuity */
+ data_block_counter = cip_header[0] & AMDTP_DBC_MASK;
+ if (data_blocks == 0 && (s->flags & CIP_EMPTY_HAS_WRONG_DBC) &&
+ s->data_block_counter != UINT_MAX)
+ data_block_counter = s->data_block_counter;
+
+ if (((s->flags & CIP_SKIP_DBC_ZERO_CHECK) && data_block_counter == 0) ||
+ (s->data_block_counter == UINT_MAX)) {
+ lost = false;
+ } else if (!(s->flags & CIP_DBC_IS_END_EVENT)) {
+ lost = data_block_counter != s->data_block_counter;
+ } else {
+ if ((data_blocks > 0) && (s->tx_dbc_interval > 0))
+ dbc_interval = s->tx_dbc_interval;
+ else
+ dbc_interval = data_blocks;
+
+ lost = data_block_counter !=
+ ((s->data_block_counter + dbc_interval) & 0xff);
+ }
+
+ if (lost) {
+ dev_info(&s->unit->device,
+ "Detect discontinuity of CIP: %02X %02X\n",
+ s->data_block_counter, data_block_counter);
+ goto err;
+ }
+
+ if (data_blocks > 0) {
+ buffer += 2;
+
+ pcm = ACCESS_ONCE(s->pcm);
+ if (pcm)
+ s->transfer_samples(s, pcm, buffer, data_blocks);
+
+ if (s->midi_ports)
+ amdtp_pull_midi(s, buffer, data_blocks);
+ }
+
+ if (s->flags & CIP_DBC_IS_END_EVENT)
+ s->data_block_counter = data_block_counter;
+ else
+ s->data_block_counter =
+ (data_block_counter + data_blocks) & 0xff;
+end:
+ if (queue_in_packet(s) < 0)
+ goto err;
+
+ if (pcm)
+ update_pcm_pointers(s, pcm, data_blocks);
+
+ return;
+err:
+ s->packet_index = -1;
+ amdtp_stream_pcm_abort(s);
+}
+
+static void out_stream_callback(struct fw_iso_context *context, u32 cycle,
+ size_t header_length, void *header,
+ void *private_data)
+{
+ struct amdtp_stream *s = private_data;
+ unsigned int i, syt, 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) {
+ syt = calculate_syt(s, ++cycle);
+ handle_out_packet(s, syt);
+ }
+ fw_iso_context_queue_flush(s->context);
+}
+
+static void in_stream_callback(struct fw_iso_context *context, u32 cycle,
+ size_t header_length, void *header,
+ void *private_data)
+{
+ struct amdtp_stream *s = private_data;
+ unsigned int p, syt, packets, payload_quadlets;
+ __be32 *buffer, *headers = header;
+
+ /* The number of packets in buffer */
+ packets = header_length / IN_PACKET_HEADER_SIZE;
+
+ for (p = 0; p < packets; p++) {
+ if (s->packet_index < 0)
+ break;
+
+ buffer = s->buffer.packets[s->packet_index].buffer;
+
+ /* Process sync slave stream */
+ if (s->sync_slave && s->sync_slave->callbacked) {
+ syt = be32_to_cpu(buffer[1]) & CIP_SYT_MASK;
+ handle_out_packet(s->sync_slave, syt);
+ }
+
+ /* The number of quadlets in this packet */
+ payload_quadlets =
+ (be32_to_cpu(headers[p]) >> ISO_DATA_LENGTH_SHIFT) / 4;
+ handle_in_packet(s, payload_quadlets, buffer);
+ }
+
+ /* Queueing error or detecting discontinuity */
+ if (s->packet_index < 0) {
+ /* Abort sync slave. */
+ if (s->sync_slave) {
+ s->sync_slave->packet_index = -1;
+ amdtp_stream_pcm_abort(s->sync_slave);
+ }
+ return;
+ }
+
+ /* when sync to device, flush the packets for slave stream */
+ if (s->sync_slave && s->sync_slave->callbacked)
+ fw_iso_context_queue_flush(s->sync_slave->context);
+
+ fw_iso_context_queue_flush(s->context);
+}
+
+/* processing is done by master callback */
+static void slave_stream_callback(struct fw_iso_context *context, u32 cycle,
+ size_t header_length, void *header,
+ void *private_data)
+{
+ return;
+}
+
+/* this is executed one time */
+static void amdtp_stream_first_callback(struct fw_iso_context *context,
+ u32 cycle, size_t header_length,
+ void *header, void *private_data)
+{
+ struct amdtp_stream *s = private_data;
+
+ /*
+ * For in-stream, first packet has come.
+ * For out-stream, prepared to transmit first packet
+ */
+ s->callbacked = true;
+ wake_up(&s->callback_wait);
+
+ if (s->direction == AMDTP_IN_STREAM)
+ context->callback.sc = in_stream_callback;
+ else if ((s->flags & CIP_BLOCKING) && (s->flags & CIP_SYNC_TO_DEVICE))
+ context->callback.sc = slave_stream_callback;
+ else
+ context->callback.sc = out_stream_callback;
+
+ context->callback.sc(context, cycle, header_length, header, s);
+}
+
+/**
+ * amdtp_stream_start - start transferring packets
+ * @s: the AMDTP 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_stream_set_parameters() and it must be started before any PCM or MIDI
+ * device can be started.
+ */
+int amdtp_stream_start(struct amdtp_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 },
+ };
+ unsigned int header_size;
+ enum dma_data_direction dir;
+ int type, tag, err;
+
+ mutex_lock(&s->mutex);
+
+ if (WARN_ON(amdtp_stream_running(s) ||
+ (s->data_block_quadlets < 1))) {
+ err = -EBADFD;
+ goto err_unlock;
+ }
+
+ if (s->direction == AMDTP_IN_STREAM &&
+ s->flags & CIP_SKIP_INIT_DBC_CHECK)
+ s->data_block_counter = UINT_MAX;
+ else
+ s->data_block_counter = 0;
+ 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;
+
+ /* initialize packet buffer */
+ if (s->direction == AMDTP_IN_STREAM) {
+ dir = DMA_FROM_DEVICE;
+ type = FW_ISO_CONTEXT_RECEIVE;
+ header_size = IN_PACKET_HEADER_SIZE;
+ } else {
+ dir = DMA_TO_DEVICE;
+ type = FW_ISO_CONTEXT_TRANSMIT;
+ header_size = OUT_PACKET_HEADER_SIZE;
+ }
+ err = iso_packets_buffer_init(&s->buffer, s->unit, QUEUE_LENGTH,
+ amdtp_stream_get_max_payload(s), dir);
+ if (err < 0)
+ goto err_unlock;
+
+ s->context = fw_iso_context_create(fw_parent_device(s->unit)->card,
+ type, channel, speed, header_size,
+ amdtp_stream_first_callback, s);
+ if (IS_ERR(s->context)) {
+ err = PTR_ERR(s->context);
+ if (err == -EBUSY)
+ dev_err(&s->unit->device,
+ "no free stream on this controller\n");
+ goto err_buffer;
+ }
+
+ amdtp_stream_update(s);
+
+ s->packet_index = 0;
+ do {
+ if (s->direction == AMDTP_IN_STREAM)
+ err = queue_in_packet(s);
+ else
+ err = queue_out_packet(s, 0, true);
+ if (err < 0)
+ goto err_context;
+ } while (s->packet_index > 0);
+
+ /* NOTE: TAG1 matches CIP. This just affects in stream. */
+ tag = FW_ISO_CONTEXT_MATCH_TAG1;
+ if (s->flags & CIP_EMPTY_WITH_TAG0)
+ tag |= FW_ISO_CONTEXT_MATCH_TAG0;
+
+ s->callbacked = false;
+ err = fw_iso_context_start(s->context, -1, 0, tag);
+ 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_stream_start);
+
+/**
+ * amdtp_stream_pcm_pointer - get the PCM buffer position
+ * @s: the AMDTP stream that transports the PCM data
+ *
+ * Returns the current buffer position, in frames.
+ */
+unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream *s)
+{
+ /* this optimization is allowed to be racy */
+ if (s->pointer_flush && amdtp_stream_running(s))
+ fw_iso_context_flush_completions(s->context);
+ else
+ s->pointer_flush = true;
+
+ return ACCESS_ONCE(s->pcm_buffer_pointer);
+}
+EXPORT_SYMBOL(amdtp_stream_pcm_pointer);
+
+/**
+ * amdtp_stream_update - update the stream after a bus reset
+ * @s: the AMDTP stream
+ */
+void amdtp_stream_update(struct amdtp_stream *s)
+{
+ ACCESS_ONCE(s->source_node_id_field) =
+ (fw_parent_device(s->unit)->card->node_id & 0x3f) << 24;
+}
+EXPORT_SYMBOL(amdtp_stream_update);
+
+/**
+ * amdtp_stream_stop - stop sending packets
+ * @s: the AMDTP stream to stop
+ *
+ * All PCM and MIDI devices of the stream must be stopped before the stream
+ * itself can be stopped.
+ */
+void amdtp_stream_stop(struct amdtp_stream *s)
+{
+ mutex_lock(&s->mutex);
+
+ if (!amdtp_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);
+
+ s->callbacked = false;
+
+ mutex_unlock(&s->mutex);
+}
+EXPORT_SYMBOL(amdtp_stream_stop);
+
+/**
+ * amdtp_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_stream_pcm_abort(struct amdtp_stream *s)
+{
+ struct snd_pcm_substream *pcm;
+
+ pcm = ACCESS_ONCE(s->pcm);
+ if (pcm)
+ snd_pcm_stop_xrun(pcm);
+}
+EXPORT_SYMBOL(amdtp_stream_pcm_abort);