ALSA: firewire-lib: complete AM824 data block processing layer
authorTakashi Sakamoto <o-takashi@sakamocchi.jp>
Sat, 19 Sep 2015 02:22:02 +0000 (11:22 +0900)
committerTakashi Iwai <tiwai@suse.de>
Tue, 29 Sep 2015 10:51:20 +0000 (12:51 +0200)
This commit moves the codes related to data block processing from packet
streaming layer to AM824 layer.

Each driver initializes amdtp stream structure for AM824 data block by
calling amdtp_am824_init(). Then, a memory block is allocated for AM824
specific structure. This memory block is released by calling
amdtp_stream_destroy().

When setting streaming parameters, it calls amdtp_am824_set_parameters().
When starting packet streaming, it calls amdtp_stream_start(). When
stopping packet streaming, it calls amdtp_stream_stop().

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
sound/firewire/amdtp-am824.c
sound/firewire/amdtp-am824.h
sound/firewire/amdtp-stream.c
sound/firewire/amdtp-stream.h

index 540a101..fe4b83f 100644 (file)
@@ -1,11 +1,14 @@
 /*
  * AM824 format in Audio and Music Data Transmission Protocol (IEC 61883-6)
  *
+ * Copyright (c) Clemens Ladisch <clemens@ladisch.de>
  * Copyright (c) 2015 Takashi Sakamoto <o-takashi@sakamocchi.jp>
  *
  * Licensed under the terms of the GNU General Public License, version 2.
  */
 
+#include <linux/slab.h>
+
 #include "amdtp-am824.h"
 
 #define CIP_FMT_AM             0x10
 /* "Clock-based rate control mode" is just supported. */
 #define AMDTP_FDF_AM824                0x00
 
+/*
+ * 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
+
+struct amdtp_am824 {
+       struct snd_rawmidi_substream *midi[AM824_MAX_CHANNELS_FOR_MIDI * 8];
+       int midi_fifo_limit;
+       int midi_fifo_used[AM824_MAX_CHANNELS_FOR_MIDI * 8];
+       unsigned int pcm_channels;
+       unsigned int midi_ports;
+
+       u8 pcm_positions[AM824_MAX_CHANNELS_FOR_PCM];
+       u8 midi_position;
+
+       void (*transfer_samples)(struct amdtp_stream *s,
+                                struct snd_pcm_substream *pcm,
+                                __be32 *buffer, unsigned int frames);
+
+       unsigned int frame_multiplier;
+};
+
 /**
  * amdtp_am824_set_parameters - set stream parameters
  * @s: the AMDTP stream to configure
@@ -30,23 +62,58 @@ int amdtp_am824_set_parameters(struct amdtp_stream *s, unsigned int rate,
                               unsigned int midi_ports,
                               bool double_pcm_frames)
 {
+       struct amdtp_am824 *p = s->protocol;
+       unsigned int midi_channels;
+       unsigned int i;
        int err;
 
-       err = amdtp_stream_set_parameters(s, rate, pcm_channels, midi_ports);
+       if (amdtp_stream_running(s))
+               return -EINVAL;
+
+       if (pcm_channels > AM824_MAX_CHANNELS_FOR_PCM)
+               return -EINVAL;
+
+       midi_channels = DIV_ROUND_UP(midi_ports, 8);
+       if (midi_channels > AM824_MAX_CHANNELS_FOR_MIDI)
+               return -EINVAL;
+
+       if (WARN_ON(amdtp_stream_running(s)) ||
+           WARN_ON(pcm_channels > AM824_MAX_CHANNELS_FOR_PCM) ||
+           WARN_ON(midi_channels > AM824_MAX_CHANNELS_FOR_MIDI))
+               return -EINVAL;
+
+       err = amdtp_stream_set_parameters(s, rate,
+                                         pcm_channels + midi_channels);
        if (err < 0)
                return err;
 
        s->fdf = AMDTP_FDF_AM824 | s->sfc;
 
+       p->pcm_channels = pcm_channels;
+       p->midi_ports = midi_ports;
+
        /*
         * In IEC 61883-6, one data block represents one event. In ALSA, one
         * event equals to one PCM frame. But Dice has a quirk at higher
         * sampling rate to transfer two PCM frames in one data block.
         */
        if (double_pcm_frames)
-               s->frame_multiplier = 2;
+               p->frame_multiplier = 2;
        else
-               s->frame_multiplier = 1;
+               p->frame_multiplier = 1;
+
+       /* init the position map for PCM and MIDI channels */
+       for (i = 0; i < pcm_channels; i++)
+               p->pcm_positions[i] = i;
+       p->midi_position = p->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().)
+        */
+       p->midi_fifo_limit = rate - MIDI_BYTES_PER_SECOND * s->syt_interval + 1;
 
        return 0;
 }
@@ -62,8 +129,10 @@ EXPORT_SYMBOL_GPL(amdtp_am824_set_parameters);
 void amdtp_am824_set_pcm_position(struct amdtp_stream *s, unsigned int index,
                                 unsigned int position)
 {
-       if (index < s->pcm_channels)
-               s->pcm_positions[index] = position;
+       struct amdtp_am824 *p = s->protocol;
+
+       if (index < p->pcm_channels)
+               p->pcm_positions[index] = position;
 }
 EXPORT_SYMBOL_GPL(amdtp_am824_set_pcm_position);
 
@@ -76,10 +145,139 @@ EXPORT_SYMBOL_GPL(amdtp_am824_set_pcm_position);
 void amdtp_am824_set_midi_position(struct amdtp_stream *s,
                                   unsigned int position)
 {
-       s->midi_position = position;
+       struct amdtp_am824 *p = s->protocol;
+
+       p->midi_position = position;
 }
 EXPORT_SYMBOL_GPL(amdtp_am824_set_midi_position);
 
+static void write_pcm_s32(struct amdtp_stream *s,
+                         struct snd_pcm_substream *pcm,
+                         __be32 *buffer, unsigned int frames)
+{
+       struct amdtp_am824 *p = s->protocol;
+       struct snd_pcm_runtime *runtime = pcm->runtime;
+       unsigned int channels, remaining_frames, i, c;
+       const u32 *src;
+
+       channels = p->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[p->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 write_pcm_s16(struct amdtp_stream *s,
+                         struct snd_pcm_substream *pcm,
+                         __be32 *buffer, unsigned int frames)
+{
+       struct amdtp_am824 *p = s->protocol;
+       struct snd_pcm_runtime *runtime = pcm->runtime;
+       unsigned int channels, remaining_frames, i, c;
+       const u16 *src;
+
+       channels = p->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[p->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 read_pcm_s32(struct amdtp_stream *s,
+                        struct snd_pcm_substream *pcm,
+                        __be32 *buffer, unsigned int frames)
+{
+       struct amdtp_am824 *p = s->protocol;
+       struct snd_pcm_runtime *runtime = pcm->runtime;
+       unsigned int channels, remaining_frames, i, c;
+       u32 *dst;
+
+       channels = p->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[p->pcm_positions[c]]) << 8;
+                       dst++;
+               }
+               buffer += s->data_block_quadlets;
+               if (--remaining_frames == 0)
+                       dst = (void *)runtime->dma_area;
+       }
+}
+
+static void write_pcm_silence(struct amdtp_stream *s,
+                             __be32 *buffer, unsigned int frames)
+{
+       struct amdtp_am824 *p = s->protocol;
+       unsigned int i, c, channels = p->pcm_channels;
+
+       for (i = 0; i < frames; ++i) {
+               for (c = 0; c < channels; ++c)
+                       buffer[p->pcm_positions[c]] = cpu_to_be32(0x40000000);
+               buffer += s->data_block_quadlets;
+       }
+}
+
+/**
+ * amdtp_am824_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_am824_set_pcm_format(struct amdtp_stream *s, snd_pcm_format_t format)
+{
+       struct amdtp_am824 *p = s->protocol;
+
+       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) {
+                       p->transfer_samples = write_pcm_s16;
+                       break;
+               }
+               WARN_ON(1);
+               /* fall through */
+       case SNDRV_PCM_FORMAT_S32:
+               if (s->direction == AMDTP_OUT_STREAM)
+                       p->transfer_samples = write_pcm_s32;
+               else
+                       p->transfer_samples = read_pcm_s32;
+               break;
+       }
+}
+EXPORT_SYMBOL_GPL(amdtp_am824_set_pcm_format);
+
 /**
  * amdtp_am824_add_pcm_hw_constraints - add hw constraints for PCM substream
  * @s:         the AMDTP stream for AM824 data block, must be initialized.
@@ -113,11 +311,135 @@ EXPORT_SYMBOL_GPL(amdtp_am824_add_pcm_hw_constraints);
 void amdtp_am824_midi_trigger(struct amdtp_stream *s, unsigned int port,
                              struct snd_rawmidi_substream *midi)
 {
-       if (port < s->midi_ports)
-               ACCESS_ONCE(s->midi[port]) = midi;
+       struct amdtp_am824 *p = s->protocol;
+
+       if (port < p->midi_ports)
+               ACCESS_ONCE(p->midi[port]) = midi;
 }
 EXPORT_SYMBOL_GPL(amdtp_am824_midi_trigger);
 
+/*
+ * 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)
+{
+       struct amdtp_am824 *p = s->protocol;
+       int used;
+
+       used = p->midi_fifo_used[port];
+       if (used == 0) /* common shortcut */
+               return true;
+
+       used -= MIDI_BYTES_PER_SECOND * s->syt_interval;
+       used = max(used, 0);
+       p->midi_fifo_used[port] = used;
+
+       return used < p->midi_fifo_limit;
+}
+
+static void midi_rate_use_one_byte(struct amdtp_stream *s, unsigned int port)
+{
+       struct amdtp_am824 *p = s->protocol;
+
+       p->midi_fifo_used[port] += amdtp_rate_table[s->sfc];
+}
+
+static void write_midi_messages(struct amdtp_stream *s, __be32 *buffer,
+                               unsigned int frames)
+{
+       struct amdtp_am824 *p = s->protocol;
+       unsigned int f, port;
+       u8 *b;
+
+       for (f = 0; f < frames; f++) {
+               b = (u8 *)&buffer[p->midi_position];
+
+               port = (s->data_block_counter + f) % 8;
+               if (f < MAX_MIDI_RX_BLOCKS &&
+                   midi_ratelimit_per_packet(s, port) &&
+                   p->midi[port] != NULL &&
+                   snd_rawmidi_transmit(p->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 read_midi_messages(struct amdtp_stream *s,
+                              __be32 *buffer, unsigned int frames)
+{
+       struct amdtp_am824 *p = s->protocol;
+       unsigned int f, port;
+       int len;
+       u8 *b;
+
+       for (f = 0; f < frames; f++) {
+               port = (s->data_block_counter + f) % 8;
+               b = (u8 *)&buffer[p->midi_position];
+
+               len = b[0] - 0x80;
+               if ((1 <= len) &&  (len <= 3) && (p->midi[port]))
+                       snd_rawmidi_receive(p->midi[port], b + 1, len);
+
+               buffer += s->data_block_quadlets;
+       }
+}
+
+unsigned int process_rx_data_blocks(struct amdtp_stream *s, __be32 *buffer,
+                                   unsigned int data_blocks, unsigned int *syt)
+{
+       struct amdtp_am824 *p = s->protocol;
+       struct snd_pcm_substream *pcm = ACCESS_ONCE(s->pcm);
+       unsigned int pcm_frames;
+
+       if (pcm) {
+               p->transfer_samples(s, pcm, buffer, data_blocks);
+               pcm_frames = data_blocks * p->frame_multiplier;
+       } else {
+               write_pcm_silence(s, buffer, data_blocks);
+               pcm_frames = 0;
+       }
+
+       if (p->midi_ports)
+               write_midi_messages(s, buffer, data_blocks);
+
+       return pcm_frames;
+}
+
+unsigned int process_tx_data_blocks(struct amdtp_stream *s, __be32 *buffer,
+                                   unsigned int data_blocks, unsigned int *syt)
+{
+       struct amdtp_am824 *p = s->protocol;
+       struct snd_pcm_substream *pcm = ACCESS_ONCE(s->pcm);
+       unsigned int pcm_frames;
+
+       if (pcm) {
+               p->transfer_samples(s, pcm, buffer, data_blocks);
+               pcm_frames = data_blocks * p->frame_multiplier;
+       } else {
+               pcm_frames = 0;
+       }
+
+       if (p->midi_ports)
+               read_midi_messages(s, buffer, data_blocks);
+
+       return pcm_frames;
+}
+
 /**
  * amdtp_am824_init - initialize an AMDTP stream structure to handle AM824
  *                   data block
@@ -129,6 +451,15 @@ EXPORT_SYMBOL_GPL(amdtp_am824_midi_trigger);
 int amdtp_am824_init(struct amdtp_stream *s, struct fw_unit *unit,
                     enum amdtp_stream_direction dir, enum cip_flags flags)
 {
-       return amdtp_stream_init(s, unit, dir, flags, CIP_FMT_AM);
+       amdtp_stream_process_data_blocks_t process_data_blocks;
+
+       if (dir == AMDTP_IN_STREAM)
+               process_data_blocks = process_tx_data_blocks;
+       else
+               process_data_blocks = process_rx_data_blocks;
+
+       return amdtp_stream_init(s, unit, dir, flags, CIP_FMT_AM,
+                                process_data_blocks,
+                                sizeof(struct amdtp_am824));
 }
 EXPORT_SYMBOL_GPL(amdtp_am824_init);
index 65e6093..73b07b3 100644 (file)
@@ -6,6 +6,27 @@
 
 #include "amdtp-stream.h"
 
+#define AM824_IN_PCM_FORMAT_BITS       SNDRV_PCM_FMTBIT_S32
+
+#define AM824_OUT_PCM_FORMAT_BITS      (SNDRV_PCM_FMTBIT_S16 | \
+                                        SNDRV_PCM_FMTBIT_S32)
+
+/*
+ * This module supports maximum 64 PCM channels for one PCM stream
+ * This is for our convenience.
+ */
+#define AM824_MAX_CHANNELS_FOR_PCM     64
+
+/*
+ * AMDTP packet can include channels for MIDI conformant data.
+ * Each MIDI conformant data channel includes 8 MPX-MIDI data stream.
+ * Each MPX-MIDI data stream includes one data stream from/to MIDI ports.
+ *
+ * This module supports maximum 1 MIDI conformant data channels.
+ * Then this AMDTP packets can transfer maximum 8 MIDI data streams.
+ */
+#define AM824_MAX_CHANNELS_FOR_MIDI    1
+
 int amdtp_am824_set_parameters(struct amdtp_stream *s, unsigned int rate,
                               unsigned int pcm_channels,
                               unsigned int midi_ports,
@@ -20,6 +41,9 @@ void amdtp_am824_set_midi_position(struct amdtp_stream *s,
 int amdtp_am824_add_pcm_hw_constraints(struct amdtp_stream *s,
                                       struct snd_pcm_runtime *runtime);
 
+void amdtp_am824_set_pcm_format(struct amdtp_stream *s,
+                               snd_pcm_format_t format);
+
 void amdtp_am824_midi_trigger(struct amdtp_stream *s, unsigned int port,
                              struct snd_rawmidi_substream *midi);
 
index c61e0ec..fa10b58 100644 (file)
 #include <linux/slab.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
-#include <sound/rawmidi.h>
 #include "amdtp-stream.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 */
@@ -74,11 +61,22 @@ static void pcm_period_tasklet(unsigned long data);
  * @dir: the direction of stream
  * @flags: the packet transmission method to use
  * @fmt: the value of fmt field in CIP header
+ * @process_data_blocks: callback handler to process data blocks
+ * @protocol_size: the size to allocate newly for protocol
  */
 int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
                      enum amdtp_stream_direction dir, enum cip_flags flags,
-                     unsigned int fmt)
+                     unsigned int fmt,
+                     amdtp_stream_process_data_blocks_t process_data_blocks,
+                     unsigned int protocol_size)
 {
+       if (process_data_blocks == NULL)
+               return -EINVAL;
+
+       s->protocol = kzalloc(protocol_size, GFP_KERNEL);
+       if (!s->protocol)
+               return -ENOMEM;
+
        s->unit = unit;
        s->direction = dir;
        s->flags = flags;
@@ -92,6 +90,7 @@ int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
        s->sync_slave = NULL;
 
        s->fmt = fmt;
+       s->process_data_blocks = process_data_blocks;
 
        return 0;
 }
@@ -104,6 +103,7 @@ EXPORT_SYMBOL(amdtp_stream_init);
 void amdtp_stream_destroy(struct amdtp_stream *s)
 {
        WARN_ON(amdtp_stream_running(s));
+       kfree(s->protocol);
        mutex_destroy(&s->mutex);
 }
 EXPORT_SYMBOL(amdtp_stream_destroy);
@@ -184,27 +184,15 @@ 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)
- * @double_pcm_frames: one data block transfers two PCM frames
+ * @data_block_quadlets: the size of a data block in quadlet unit
  *
  * The parameters must be set before the stream is started, and must not be
  * changed while the stream is running.
  */
-int amdtp_stream_set_parameters(struct amdtp_stream *s,
-                               unsigned int rate,
-                               unsigned int pcm_channels,
-                               unsigned int midi_ports)
+int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
+                               unsigned int data_block_quadlets)
 {
-       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 > AM824_MAX_CHANNELS_FOR_PCM) ||
-           WARN_ON(midi_channels > AM824_MAX_CHANNELS_FOR_MIDI))
-               return -EINVAL;
+       unsigned int sfc;
 
        for (sfc = 0; sfc < ARRAY_SIZE(amdtp_rate_table); ++sfc) {
                if (amdtp_rate_table[sfc] == rate)
@@ -213,11 +201,8 @@ int amdtp_stream_set_parameters(struct amdtp_stream *s,
        if (sfc == ARRAY_SIZE(amdtp_rate_table))
                return -EINVAL;
 
-       s->pcm_channels = pcm_channels;
        s->sfc = sfc;
-       s->data_block_quadlets = s->pcm_channels + midi_channels;
-       s->midi_ports = midi_ports;
-
+       s->data_block_quadlets = data_block_quadlets;
        s->syt_interval = amdtp_syt_intervals[sfc];
 
        /* default buffering in the device */
@@ -226,19 +211,6 @@ int amdtp_stream_set_parameters(struct amdtp_stream *s,
                /* 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;
-
        return 0;
 }
 EXPORT_SYMBOL(amdtp_stream_set_parameters);
@@ -261,51 +233,6 @@ unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s)
 }
 EXPORT_SYMBOL(amdtp_stream_get_max_payload);
 
-static void write_pcm_s16(struct amdtp_stream *s,
-                         struct snd_pcm_substream *pcm,
-                         __be32 *buffer, unsigned int frames);
-static void write_pcm_s32(struct amdtp_stream *s,
-                         struct snd_pcm_substream *pcm,
-                         __be32 *buffer, unsigned int frames);
-static void read_pcm_s32(struct amdtp_stream *s,
-                        struct snd_pcm_substream *pcm,
-                        __be32 *buffer, unsigned int frames);
-
-/**
- * amdtp_am824_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_am824_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 = write_pcm_s16;
-                       break;
-               }
-               WARN_ON(1);
-               /* fall through */
-       case SNDRV_PCM_FORMAT_S32:
-               if (s->direction == AMDTP_OUT_STREAM)
-                       s->transfer_samples = write_pcm_s32;
-               else
-                       s->transfer_samples = read_pcm_s32;
-               break;
-       }
-}
-EXPORT_SYMBOL_GPL(amdtp_am824_set_pcm_format);
-
 /**
  * amdtp_stream_pcm_prepare - prepare PCM device for running
  * @s: the AMDTP stream
@@ -408,168 +335,6 @@ static unsigned int calculate_syt(struct amdtp_stream *s,
        }
 }
 
-static void write_pcm_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 write_pcm_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 read_pcm_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 write_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 write_midi_messages(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 read_midi_messages(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)
@@ -639,26 +404,6 @@ static inline int queue_in_packet(struct amdtp_stream *s)
                            amdtp_stream_get_max_payload(s), false);
 }
 
-unsigned int process_rx_data_blocks(struct amdtp_stream *s, __be32 *buffer,
-                                   unsigned int data_blocks, unsigned int *syt)
-{
-       struct snd_pcm_substream *pcm = ACCESS_ONCE(s->pcm);
-       unsigned int pcm_frames;
-
-       if (pcm) {
-               s->transfer_samples(s, pcm, buffer, data_blocks);
-               pcm_frames = data_blocks * s->frame_multiplier;
-       } else {
-               write_pcm_silence(s, buffer, data_blocks);
-               pcm_frames = 0;
-       }
-
-       if (s->midi_ports)
-               write_midi_messages(s, buffer, data_blocks);
-
-       return pcm_frames;
-}
-
 static int handle_out_packet(struct amdtp_stream *s, unsigned int data_blocks,
                             unsigned int syt)
 {
@@ -668,7 +413,7 @@ static int handle_out_packet(struct amdtp_stream *s, unsigned int data_blocks,
        struct snd_pcm_substream *pcm;
 
        buffer = s->buffer.packets[s->packet_index].buffer;
-       pcm_frames = process_rx_data_blocks(s, buffer + 2, data_blocks, &syt);
+       pcm_frames = s->process_data_blocks(s, buffer + 2, data_blocks, &syt);
 
        buffer[0] = cpu_to_be32(ACCESS_ONCE(s->source_node_id_field) |
                                (s->data_block_quadlets << CIP_DBS_SHIFT) |
@@ -692,25 +437,6 @@ static int handle_out_packet(struct amdtp_stream *s, unsigned int data_blocks,
        return 0;
 }
 
-unsigned int process_tx_data_blocks(struct amdtp_stream *s, __be32 *buffer,
-                                   unsigned int data_blocks, unsigned int *syt)
-{
-       struct snd_pcm_substream *pcm = ACCESS_ONCE(s->pcm);
-       unsigned int pcm_frames;
-
-       if (pcm) {
-               s->transfer_samples(s, pcm, buffer, data_blocks);
-               pcm_frames = data_blocks * s->frame_multiplier;
-       } else {
-               pcm_frames = 0;
-       }
-
-       if (s->midi_ports)
-               read_midi_messages(s, buffer, data_blocks);
-
-       return pcm_frames;
-}
-
 static int handle_in_packet(struct amdtp_stream *s,
                            unsigned int payload_quadlets, __be32 *buffer,
                            unsigned int *data_blocks, unsigned int syt)
@@ -798,7 +524,7 @@ static int handle_in_packet(struct amdtp_stream *s,
                return -EIO;
        }
 
-       pcm_frames = process_tx_data_blocks(s, buffer + 2, *data_blocks, &syt);
+       pcm_frames = s->process_data_blocks(s, buffer + 2, *data_blocks, &syt);
 
        if (s->flags & CIP_DBC_IS_END_EVENT)
                s->data_block_counter = data_block_counter;
index 71f4f75..8775704 100644 (file)
@@ -81,39 +81,22 @@ enum cip_sfc {
        CIP_SFC_COUNT
 };
 
-#define AM824_IN_PCM_FORMAT_BITS       SNDRV_PCM_FMTBIT_S32
-
-#define AM824_OUT_PCM_FORMAT_BITS      (SNDRV_PCM_FMTBIT_S16 | \
-                                        SNDRV_PCM_FMTBIT_S32)
-
-
-/*
- * This module supports maximum 64 PCM channels for one PCM stream
- * This is for our convenience.
- */
-#define AM824_MAX_CHANNELS_FOR_PCM     64
-
-/*
- * AMDTP packet can include channels for MIDI conformant data.
- * Each MIDI conformant data channel includes 8 MPX-MIDI data stream.
- * Each MPX-MIDI data stream includes one data stream from/to MIDI ports.
- *
- * This module supports maximum 1 MIDI conformant data channels.
- * Then this AMDTP packets can transfer maximum 8 MIDI data streams.
- */
-#define AM824_MAX_CHANNELS_FOR_MIDI    1
-
 struct fw_unit;
 struct fw_iso_context;
 struct snd_pcm_substream;
 struct snd_pcm_runtime;
-struct snd_rawmidi_substream;
 
 enum amdtp_stream_direction {
        AMDTP_OUT_STREAM = 0,
        AMDTP_IN_STREAM
 };
 
+struct amdtp_stream;
+typedef unsigned int (*amdtp_stream_process_data_blocks_t)(
+                                               struct amdtp_stream *s,
+                                               __be32 *buffer,
+                                               unsigned int data_blocks,
+                                               unsigned int *syt);
 struct amdtp_stream {
        struct fw_unit *unit;
        enum cip_flags flags;
@@ -156,32 +139,20 @@ struct amdtp_stream {
        wait_queue_head_t callback_wait;
        struct amdtp_stream *sync_slave;
 
-       /* For AM824 processing. */
-       struct snd_rawmidi_substream *midi[AM824_MAX_CHANNELS_FOR_MIDI * 8];
-       int midi_fifo_limit;
-       int midi_fifo_used[AM824_MAX_CHANNELS_FOR_MIDI * 8];
-       unsigned int pcm_channels;
-       unsigned int midi_ports;
-
-       u8 pcm_positions[AM824_MAX_CHANNELS_FOR_PCM];
-       u8 midi_position;
-
-       void (*transfer_samples)(struct amdtp_stream *s,
-                                struct snd_pcm_substream *pcm,
-                                __be32 *buffer, unsigned int frames);
-
-       unsigned int frame_multiplier;
+       /* For backends to process data blocks. */
+       void *protocol;
+       amdtp_stream_process_data_blocks_t process_data_blocks;
 };
 
 int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
-                     enum amdtp_stream_direction dir,
-                     enum cip_flags flags, unsigned int fmt);
+                     enum amdtp_stream_direction dir, enum cip_flags flags,
+                     unsigned int fmt,
+                     amdtp_stream_process_data_blocks_t process_data_blocks,
+                     unsigned int protocol_size);
 void amdtp_stream_destroy(struct amdtp_stream *s);
 
-int amdtp_stream_set_parameters(struct amdtp_stream *s,
-                               unsigned int rate,
-                               unsigned int pcm_channels,
-                               unsigned int midi_ports);
+int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
+                               unsigned int data_block_quadlets);
 unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
 
 int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed);
@@ -190,8 +161,7 @@ void amdtp_stream_stop(struct amdtp_stream *s);
 
 int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
                                        struct snd_pcm_runtime *runtime);
-void amdtp_am824_set_pcm_format(struct amdtp_stream *s,
-                               snd_pcm_format_t format);
+
 void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
 unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream *s);
 void amdtp_stream_pcm_abort(struct amdtp_stream *s);