xref: /linux/sound/firewire/motu/motu-stream.c (revision c316cf670491def52a396d3bdc5a63ad01f7fefa)
1 /*
2  * motu-stream.c - a part of driver for MOTU FireWire series
3  *
4  * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
5  *
6  * Licensed under the terms of the GNU General Public License, version 2.
7  */
8 
9 #include "motu.h"
10 
11 #define	CALLBACK_TIMEOUT	200
12 
13 #define ISOC_COMM_CONTROL_OFFSET		0x0b00
14 #define  ISOC_COMM_CONTROL_MASK			0xffff0000
15 #define  CHANGE_RX_ISOC_COMM_STATE		0x80000000
16 #define  RX_ISOC_COMM_IS_ACTIVATED		0x40000000
17 #define  RX_ISOC_COMM_CHANNEL_MASK		0x3f000000
18 #define  RX_ISOC_COMM_CHANNEL_SHIFT		24
19 #define  CHANGE_TX_ISOC_COMM_STATE		0x00800000
20 #define  TX_ISOC_COMM_IS_ACTIVATED		0x00400000
21 #define  TX_ISOC_COMM_CHANNEL_MASK		0x003f0000
22 #define  TX_ISOC_COMM_CHANNEL_SHIFT		16
23 
24 #define PACKET_FORMAT_OFFSET			0x0b10
25 #define  TX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS	0x00000080
26 #define  RX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS	0x00000040
27 #define  TX_PACKET_TRANSMISSION_SPEED_MASK	0x0000000f
28 
29 static int start_both_streams(struct snd_motu *motu, unsigned int rate)
30 {
31 	unsigned int midi_ports = 0;
32 	__be32 reg;
33 	u32 data;
34 	int err;
35 
36 	if (motu->spec->flags & SND_MOTU_SPEC_HAS_MIDI)
37 		midi_ports = 1;
38 
39 	/* Set packet formation to our packet streaming engine. */
40 	err = amdtp_motu_set_parameters(&motu->rx_stream, rate, midi_ports,
41 					&motu->rx_packet_formats);
42 	if (err < 0)
43 		return err;
44 
45 	err = amdtp_motu_set_parameters(&motu->tx_stream, rate, midi_ports,
46 					&motu->tx_packet_formats);
47 	if (err < 0)
48 		return err;
49 
50 	/* Get isochronous resources on the bus. */
51 	err = fw_iso_resources_allocate(&motu->rx_resources,
52 				amdtp_stream_get_max_payload(&motu->rx_stream),
53 				fw_parent_device(motu->unit)->max_speed);
54 	if (err < 0)
55 		return err;
56 
57 	err = fw_iso_resources_allocate(&motu->tx_resources,
58 				amdtp_stream_get_max_payload(&motu->tx_stream),
59 				fw_parent_device(motu->unit)->max_speed);
60 	if (err < 0)
61 		return err;
62 
63 	/* Configure the unit to start isochronous communication. */
64 	err = snd_motu_transaction_read(motu, ISOC_COMM_CONTROL_OFFSET, &reg,
65 					sizeof(reg));
66 	if (err < 0)
67 		return err;
68 	data = be32_to_cpu(reg) & ~ISOC_COMM_CONTROL_MASK;
69 
70 	data |= CHANGE_RX_ISOC_COMM_STATE | RX_ISOC_COMM_IS_ACTIVATED |
71 		(motu->rx_resources.channel << RX_ISOC_COMM_CHANNEL_SHIFT) |
72 		CHANGE_TX_ISOC_COMM_STATE | TX_ISOC_COMM_IS_ACTIVATED |
73 		(motu->tx_resources.channel << TX_ISOC_COMM_CHANNEL_SHIFT);
74 
75 	reg = cpu_to_be32(data);
76 	return snd_motu_transaction_write(motu, ISOC_COMM_CONTROL_OFFSET, &reg,
77 					  sizeof(reg));
78 }
79 
80 static void stop_both_streams(struct snd_motu *motu)
81 {
82 	__be32 reg;
83 	u32 data;
84 	int err;
85 
86 	err = motu->spec->protocol->switch_fetching_mode(motu, false);
87 	if (err < 0)
88 		return;
89 
90 	err = snd_motu_transaction_read(motu, ISOC_COMM_CONTROL_OFFSET, &reg,
91 					sizeof(reg));
92 	if (err < 0)
93 		return;
94 	data = be32_to_cpu(reg);
95 
96 	data &= ~(RX_ISOC_COMM_IS_ACTIVATED | TX_ISOC_COMM_IS_ACTIVATED);
97 	data |= CHANGE_RX_ISOC_COMM_STATE | CHANGE_TX_ISOC_COMM_STATE;
98 
99 	reg = cpu_to_be32(data);
100 	snd_motu_transaction_write(motu, ISOC_COMM_CONTROL_OFFSET, &reg,
101 				   sizeof(reg));
102 
103 	fw_iso_resources_free(&motu->tx_resources);
104 	fw_iso_resources_free(&motu->rx_resources);
105 }
106 
107 static int start_isoc_ctx(struct snd_motu *motu, struct amdtp_stream *stream)
108 {
109 	struct fw_iso_resources *resources;
110 	int err;
111 
112 	if (stream == &motu->rx_stream)
113 		resources = &motu->rx_resources;
114 	else
115 		resources = &motu->tx_resources;
116 
117 	err = amdtp_stream_start(stream, resources->channel,
118 				 fw_parent_device(motu->unit)->max_speed);
119 	if (err < 0)
120 		return err;
121 
122 	if (!amdtp_stream_wait_callback(stream, CALLBACK_TIMEOUT)) {
123 		amdtp_stream_stop(stream);
124 		fw_iso_resources_free(resources);
125 		return -ETIMEDOUT;
126 	}
127 
128 	return 0;
129 }
130 
131 static void stop_isoc_ctx(struct snd_motu *motu, struct amdtp_stream *stream)
132 {
133 	struct fw_iso_resources *resources;
134 
135 	if (stream == &motu->rx_stream)
136 		resources = &motu->rx_resources;
137 	else
138 		resources = &motu->tx_resources;
139 
140 	amdtp_stream_stop(stream);
141 	fw_iso_resources_free(resources);
142 }
143 
144 static int ensure_packet_formats(struct snd_motu *motu)
145 {
146 	__be32 reg;
147 	u32 data;
148 	int err;
149 
150 	err = snd_motu_transaction_read(motu, PACKET_FORMAT_OFFSET, &reg,
151 					sizeof(reg));
152 	if (err < 0)
153 		return err;
154 	data = be32_to_cpu(reg);
155 
156 	data &= ~(TX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS |
157 		  RX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS|
158 		  TX_PACKET_TRANSMISSION_SPEED_MASK);
159 	if (motu->tx_packet_formats.differed_part_pcm_chunks[0] == 0)
160 		data |= TX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS;
161 	if (motu->rx_packet_formats.differed_part_pcm_chunks[0] == 0)
162 		data |= RX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS;
163 	data |= fw_parent_device(motu->unit)->max_speed;
164 
165 	reg = cpu_to_be32(data);
166 	return snd_motu_transaction_write(motu, PACKET_FORMAT_OFFSET, &reg,
167 					  sizeof(reg));
168 }
169 
170 int snd_motu_stream_start_duplex(struct snd_motu *motu, unsigned int rate)
171 {
172 	const struct snd_motu_protocol *protocol = motu->spec->protocol;
173 	unsigned int curr_rate;
174 	int err = 0;
175 
176 	if (motu->capture_substreams == 0 && motu->playback_substreams == 0)
177 		return 0;
178 
179 	/* Some packet queueing errors. */
180 	if (amdtp_streaming_error(&motu->rx_stream) ||
181 	    amdtp_streaming_error(&motu->tx_stream)) {
182 		amdtp_stream_stop(&motu->rx_stream);
183 		amdtp_stream_stop(&motu->tx_stream);
184 		stop_both_streams(motu);
185 	}
186 
187 	err = protocol->cache_packet_formats(motu);
188 	if (err < 0)
189 		return err;
190 
191 	/* Stop stream if rate is different. */
192 	err = protocol->get_clock_rate(motu, &curr_rate);
193 	if (err < 0) {
194 		dev_err(&motu->unit->device,
195 			"fail to get sampling rate: %d\n", err);
196 		return err;
197 	}
198 	if (rate == 0)
199 		rate = curr_rate;
200 	if (rate != curr_rate) {
201 		amdtp_stream_stop(&motu->rx_stream);
202 		amdtp_stream_stop(&motu->tx_stream);
203 		stop_both_streams(motu);
204 	}
205 
206 	if (!amdtp_stream_running(&motu->rx_stream)) {
207 		err = protocol->set_clock_rate(motu, rate);
208 		if (err < 0) {
209 			dev_err(&motu->unit->device,
210 				"fail to set sampling rate: %d\n", err);
211 			return err;
212 		}
213 
214 		err = ensure_packet_formats(motu);
215 		if (err < 0)
216 			return err;
217 
218 		err = start_both_streams(motu, rate);
219 		if (err < 0) {
220 			dev_err(&motu->unit->device,
221 				"fail to start isochronous comm: %d\n", err);
222 			stop_both_streams(motu);
223 			return err;
224 		}
225 
226 		err = start_isoc_ctx(motu, &motu->rx_stream);
227 		if (err < 0) {
228 			dev_err(&motu->unit->device,
229 				"fail to start IT context: %d\n", err);
230 			stop_both_streams(motu);
231 			return err;
232 		}
233 
234 		err = protocol->switch_fetching_mode(motu, true);
235 		if (err < 0) {
236 			dev_err(&motu->unit->device,
237 				"fail to enable frame fetching: %d\n", err);
238 			stop_both_streams(motu);
239 			return err;
240 		}
241 	}
242 
243 	if (!amdtp_stream_running(&motu->tx_stream) &&
244 	    motu->capture_substreams > 0) {
245 		err = start_isoc_ctx(motu, &motu->tx_stream);
246 		if (err < 0) {
247 			dev_err(&motu->unit->device,
248 				"fail to start IR context: %d", err);
249 			amdtp_stream_stop(&motu->rx_stream);
250 			stop_both_streams(motu);
251 			return err;
252 		}
253 	}
254 
255 	return 0;
256 }
257 
258 void snd_motu_stream_stop_duplex(struct snd_motu *motu)
259 {
260 	if (motu->capture_substreams == 0) {
261 		if (amdtp_stream_running(&motu->tx_stream))
262 			stop_isoc_ctx(motu, &motu->tx_stream);
263 
264 		if (motu->playback_substreams == 0) {
265 			if (amdtp_stream_running(&motu->rx_stream))
266 				stop_isoc_ctx(motu, &motu->rx_stream);
267 			stop_both_streams(motu);
268 		}
269 	}
270 }
271 
272 static int init_stream(struct snd_motu *motu, enum amdtp_stream_direction dir)
273 {
274 	int err;
275 	struct amdtp_stream *stream;
276 	struct fw_iso_resources *resources;
277 
278 	if (dir == AMDTP_IN_STREAM) {
279 		stream = &motu->tx_stream;
280 		resources = &motu->tx_resources;
281 	} else {
282 		stream = &motu->rx_stream;
283 		resources = &motu->rx_resources;
284 	}
285 
286 	err = fw_iso_resources_init(resources, motu->unit);
287 	if (err < 0)
288 		return err;
289 
290 	err = amdtp_motu_init(stream, motu->unit, dir, motu->spec->protocol);
291 	if (err < 0) {
292 		amdtp_stream_destroy(stream);
293 		fw_iso_resources_destroy(resources);
294 	}
295 
296 	return err;
297 }
298 
299 static void destroy_stream(struct snd_motu *motu,
300 			   enum amdtp_stream_direction dir)
301 {
302 	struct amdtp_stream *stream;
303 	struct fw_iso_resources *resources;
304 
305 	if (dir == AMDTP_IN_STREAM) {
306 		stream = &motu->tx_stream;
307 		resources = &motu->tx_resources;
308 	} else {
309 		stream = &motu->rx_stream;
310 		resources = &motu->rx_resources;
311 	}
312 
313 	amdtp_stream_destroy(stream);
314 	fw_iso_resources_free(resources);
315 }
316 
317 int snd_motu_stream_init_duplex(struct snd_motu *motu)
318 {
319 	int err;
320 
321 	err = init_stream(motu, AMDTP_IN_STREAM);
322 	if (err < 0)
323 		return err;
324 
325 	err = init_stream(motu, AMDTP_OUT_STREAM);
326 	if (err < 0)
327 		destroy_stream(motu, AMDTP_IN_STREAM);
328 
329 	return err;
330 }
331 
332 /*
333  * This function should be called before starting streams or after stopping
334  * streams.
335  */
336 void snd_motu_stream_destroy_duplex(struct snd_motu *motu)
337 {
338 	destroy_stream(motu, AMDTP_IN_STREAM);
339 	destroy_stream(motu, AMDTP_OUT_STREAM);
340 
341 	motu->playback_substreams = 0;
342 	motu->capture_substreams = 0;
343 }
344 
345 static void motu_lock_changed(struct snd_motu *motu)
346 {
347 	motu->dev_lock_changed = true;
348 	wake_up(&motu->hwdep_wait);
349 }
350 
351 int snd_motu_stream_lock_try(struct snd_motu *motu)
352 {
353 	int err;
354 
355 	spin_lock_irq(&motu->lock);
356 
357 	if (motu->dev_lock_count < 0) {
358 		err = -EBUSY;
359 		goto out;
360 	}
361 
362 	if (motu->dev_lock_count++ == 0)
363 		motu_lock_changed(motu);
364 	err = 0;
365 out:
366 	spin_unlock_irq(&motu->lock);
367 	return err;
368 }
369 
370 void snd_motu_stream_lock_release(struct snd_motu *motu)
371 {
372 	spin_lock_irq(&motu->lock);
373 
374 	if (WARN_ON(motu->dev_lock_count <= 0))
375 		goto out;
376 
377 	if (--motu->dev_lock_count == 0)
378 		motu_lock_changed(motu);
379 out:
380 	spin_unlock_irq(&motu->lock);
381 }
382