diff options
Diffstat (limited to 'sound/firewire/amdtp.c')
| -rw-r--r-- | sound/firewire/amdtp.c | 1007 | 
1 files changed, 1007 insertions, 0 deletions
diff --git a/sound/firewire/amdtp.c b/sound/firewire/amdtp.c new file mode 100644 index 00000000000..f96bf4c7c23 --- /dev/null +++ b/sound/firewire/amdtp.c @@ -0,0 +1,1007 @@ +/* + * 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) + +#define TRANSFER_DELAY_TICKS	0x2e00 /* 479.17 µs */ + +/* 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 = fw_unit_get(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; + +	s->rx_blocks_for_midi = UINT_MAX; + +	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); +	fw_unit_put(s->unit); +} +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 aligh period/buffer sizes to current SYT_INTERVAL. +	 * +	 * TODO: These constraints can be improved with propper rules. +	 * Currently apply LCM of SYT_INTEVALs. +	 */ +	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; +} +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 paramters (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; +	} +} + +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++) { +		buffer[s->midi_position] = 0; +		b = (u8 *)&buffer[s->midi_position]; + +		port = (s->data_block_counter + f) % 8; +		if ((f >= s->rx_blocks_for_midi) || +		    (s->midi[port] == NULL) || +		    (snd_rawmidi_transmit(s->midi[port], b + 1, 1) <= 0)) +			b[0] = 0x80; +		else +			b[0] = 0x81; + +		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; + +	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_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_stream_pcm_abort);  | 
