amdtp-tascam.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * amdtp-tascam.c - a part of driver for TASCAM FireWire series
  4 *
  5 * Copyright (c) 2015 Takashi Sakamoto
  6 */
  7
  8#include <sound/pcm.h>
  9#include "tascam.h"
 10
 11#define AMDTP_FMT_TSCM_TX	0x1e
 12#define AMDTP_FMT_TSCM_RX	0x3e
 13
 14struct amdtp_tscm {
 15	unsigned int pcm_channels;
 16};
 17
 18int amdtp_tscm_set_parameters(struct amdtp_stream *s, unsigned int rate)
 19{
 20	struct amdtp_tscm *p = s->protocol;
 21	unsigned int data_channels;
 22
 23	if (amdtp_stream_running(s))
 24		return -EBUSY;
 25
 26	data_channels = p->pcm_channels;
 27
 28	/* Packets in in-stream have extra 2 data channels. */
 29	if (s->direction == AMDTP_IN_STREAM)
 30		data_channels += 2;
 31
 32	return amdtp_stream_set_parameters(s, rate, data_channels, 1);
 33}
 34
 35static void write_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
 36			  __be32 *buffer, unsigned int frames,
 37			  unsigned int pcm_frames)
 38{
 39	struct amdtp_tscm *p = s->protocol;
 40	unsigned int channels = p->pcm_channels;
 41	struct snd_pcm_runtime *runtime = pcm->runtime;
 42	unsigned int pcm_buffer_pointer;
 43	int remaining_frames;
 44	const u32 *src;
 45	int i, c;
 46
 47	pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
 48	pcm_buffer_pointer %= runtime->buffer_size;
 49
 50	src = (void *)runtime->dma_area +
 51				frames_to_bytes(runtime, pcm_buffer_pointer);
 52	remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
 53
 54	for (i = 0; i < frames; ++i) {
 55		for (c = 0; c < channels; ++c) {
 56			buffer[c] = cpu_to_be32(*src);
 57			src++;
 58		}
 59		buffer += s->data_block_quadlets;
 60		if (--remaining_frames == 0)
 61			src = (void *)runtime->dma_area;
 62	}
 63}
 64
 65static void read_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
 66			 __be32 *buffer, unsigned int frames,
 67			 unsigned int pcm_frames)
 68{
 69	struct amdtp_tscm *p = s->protocol;
 70	unsigned int channels = p->pcm_channels;
 71	struct snd_pcm_runtime *runtime = pcm->runtime;
 72	unsigned int pcm_buffer_pointer;
 73	int remaining_frames;
 74	u32 *dst;
 75	int i, c;
 76
 77	pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
 78	pcm_buffer_pointer %= runtime->buffer_size;
 79
 80	dst  = (void *)runtime->dma_area +
 81				frames_to_bytes(runtime, pcm_buffer_pointer);
 82	remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
 83
 84	/* The first data channel is for event counter. */
 85	buffer += 1;
 86
 87	for (i = 0; i < frames; ++i) {
 88		for (c = 0; c < channels; ++c) {
 89			*dst = be32_to_cpu(buffer[c]);
 90			dst++;
 91		}
 92		buffer += s->data_block_quadlets;
 93		if (--remaining_frames == 0)
 94			dst = (void *)runtime->dma_area;
 95	}
 96}
 97
 98static void write_pcm_silence(struct amdtp_stream *s, __be32 *buffer,
 99			      unsigned int data_blocks)
100{
101	struct amdtp_tscm *p = s->protocol;
102	unsigned int channels, i, c;
103
104	channels = p->pcm_channels;
105
106	for (i = 0; i < data_blocks; ++i) {
107		for (c = 0; c < channels; ++c)
108			buffer[c] = 0x00000000;
109		buffer += s->data_block_quadlets;
110	}
111}
112
113int amdtp_tscm_add_pcm_hw_constraints(struct amdtp_stream *s,
114				      struct snd_pcm_runtime *runtime)
115{
116	int err;
117
118	/*
119	 * Our implementation allows this protocol to deliver 24 bit sample in
120	 * 32bit data channel.
121	 */
122	err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);
123	if (err < 0)
124		return err;
125
126	return amdtp_stream_add_pcm_hw_constraints(s, runtime);
127}
128
129static void read_status_messages(struct amdtp_stream *s,
130				 __be32 *buffer, unsigned int data_blocks)
131{
132	struct snd_tscm *tscm = container_of(s, struct snd_tscm, tx_stream);
133	bool used = READ_ONCE(tscm->hwdep->used);
134	int i;
135
136	for (i = 0; i < data_blocks; i++) {
137		unsigned int index;
138		__be32 before;
139		__be32 after;
140
141		index = be32_to_cpu(buffer[0]) % SNDRV_FIREWIRE_TASCAM_STATE_COUNT;
142		before = tscm->state[index];
143		after = buffer[s->data_block_quadlets - 1];
144
145		if (used && index > 4 && index < 16) {
146			__be32 mask;
147
148			if (index == 5)
149				mask = cpu_to_be32(~0x0000ffff);
150			else if (index == 6)
151				mask = cpu_to_be32(~0x0000ffff);
152			else if (index == 8)
153				mask = cpu_to_be32(~0x000f0f00);
154			else
155				mask = cpu_to_be32(~0x00000000);
156
157			if ((before ^ after) & mask) {
158				struct snd_firewire_tascam_change *entry =
159						&tscm->queue[tscm->push_pos];
160
161				scoped_guard(spinlock_irqsave, &tscm->lock) {
162					entry->index = index;
163					entry->before = before;
164					entry->after = after;
165					if (++tscm->push_pos >= SND_TSCM_QUEUE_COUNT)
166						tscm->push_pos = 0;
167				}
168
169				wake_up(&tscm->hwdep_wait);
170			}
171		}
172
173		tscm->state[index] = after;
174		buffer += s->data_block_quadlets;
175	}
176}
177
178static void process_ir_ctx_payloads(struct amdtp_stream *s, const struct pkt_desc *desc,
179				    unsigned int count, struct snd_pcm_substream *pcm)
180{
181	unsigned int pcm_frames = 0;
182	int i;
183
184	for (i = 0; i < count; ++i) {
185		__be32 *buf = desc->ctx_payload;
186		unsigned int data_blocks = desc->data_blocks;
187
188		if (pcm) {
189			read_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
190			pcm_frames += data_blocks;
191		}
192
193		read_status_messages(s, buf, data_blocks);
194
195		desc = amdtp_stream_next_packet_desc(s, desc);
196	}
197}
198
199static void process_it_ctx_payloads(struct amdtp_stream *s, const struct pkt_desc *desc,
200				    unsigned int count, struct snd_pcm_substream *pcm)
201{
202	unsigned int pcm_frames = 0;
203	int i;
204
205	for (i = 0; i < count; ++i) {
206		__be32 *buf = desc->ctx_payload;
207		unsigned int data_blocks = desc->data_blocks;
208
209		if (pcm) {
210			write_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
211			pcm_frames += data_blocks;
212		} else {
213			write_pcm_silence(s, buf, data_blocks);
214		}
215
216		desc = amdtp_stream_next_packet_desc(s, desc);
217	}
218}
219
220int amdtp_tscm_init(struct amdtp_stream *s, struct fw_unit *unit,
221		    enum amdtp_stream_direction dir, unsigned int pcm_channels)
222{
223	amdtp_stream_process_ctx_payloads_t process_ctx_payloads;
224	unsigned int flags = CIP_NONBLOCKING | CIP_SKIP_DBC_ZERO_CHECK | CIP_UNAWARE_SYT;
225	struct amdtp_tscm *p;
226	unsigned int fmt;
227	int err;
228
229	if (dir == AMDTP_IN_STREAM) {
230		fmt = AMDTP_FMT_TSCM_TX;
231		process_ctx_payloads = process_ir_ctx_payloads;
232	} else {
233		fmt = AMDTP_FMT_TSCM_RX;
234		process_ctx_payloads = process_it_ctx_payloads;
235	}
236
237	err = amdtp_stream_init(s, unit, dir, flags, fmt,
238			process_ctx_payloads, sizeof(struct amdtp_tscm));
239	if (err < 0)
240		return err;
241
242	if (dir == AMDTP_OUT_STREAM) {
243		// Use fixed value for FDF field.
244		s->ctx_data.rx.fdf = 0x00;
245	}
246
247	/* This protocol uses fixed number of data channels for PCM samples. */
248	p = s->protocol;
249	p->pcm_channels = pcm_channels;
250
251	return 0;
252}