1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ff-stream.c - a part of driver for RME Fireface series
4  *
5  * Copyright (c) 2015-2017 Takashi Sakamoto
6  */
7 
8 #include "ff.h"
9 
10 #define READY_TIMEOUT_MS	200
11 
snd_ff_stream_get_multiplier_mode(enum cip_sfc sfc,enum snd_ff_stream_mode * mode)12 int snd_ff_stream_get_multiplier_mode(enum cip_sfc sfc,
13 				      enum snd_ff_stream_mode *mode)
14 {
15 	static const enum snd_ff_stream_mode modes[] = {
16 		[CIP_SFC_32000] = SND_FF_STREAM_MODE_LOW,
17 		[CIP_SFC_44100] = SND_FF_STREAM_MODE_LOW,
18 		[CIP_SFC_48000] = SND_FF_STREAM_MODE_LOW,
19 		[CIP_SFC_88200] = SND_FF_STREAM_MODE_MID,
20 		[CIP_SFC_96000] = SND_FF_STREAM_MODE_MID,
21 		[CIP_SFC_176400] = SND_FF_STREAM_MODE_HIGH,
22 		[CIP_SFC_192000] = SND_FF_STREAM_MODE_HIGH,
23 	};
24 
25 	if (sfc >= CIP_SFC_COUNT)
26 		return -EINVAL;
27 
28 	*mode = modes[sfc];
29 
30 	return 0;
31 }
32 
finish_session(struct snd_ff * ff)33 static inline void finish_session(struct snd_ff *ff)
34 {
35 	ff->spec->protocol->finish_session(ff);
36 	ff->spec->protocol->switch_fetching_mode(ff, false);
37 }
38 
init_stream(struct snd_ff * ff,struct amdtp_stream * s)39 static int init_stream(struct snd_ff *ff, struct amdtp_stream *s)
40 {
41 	struct fw_iso_resources *resources;
42 	enum amdtp_stream_direction dir;
43 	int err;
44 
45 	if (s == &ff->tx_stream) {
46 		resources = &ff->tx_resources;
47 		dir = AMDTP_IN_STREAM;
48 	} else {
49 		resources = &ff->rx_resources;
50 		dir = AMDTP_OUT_STREAM;
51 	}
52 
53 	err = fw_iso_resources_init(resources, ff->unit);
54 	if (err < 0)
55 		return err;
56 
57 	err = amdtp_ff_init(s, ff->unit, dir);
58 	if (err < 0)
59 		fw_iso_resources_destroy(resources);
60 
61 	return err;
62 }
63 
destroy_stream(struct snd_ff * ff,struct amdtp_stream * s)64 static void destroy_stream(struct snd_ff *ff, struct amdtp_stream *s)
65 {
66 	amdtp_stream_destroy(s);
67 
68 	if (s == &ff->tx_stream)
69 		fw_iso_resources_destroy(&ff->tx_resources);
70 	else
71 		fw_iso_resources_destroy(&ff->rx_resources);
72 }
73 
snd_ff_stream_init_duplex(struct snd_ff * ff)74 int snd_ff_stream_init_duplex(struct snd_ff *ff)
75 {
76 	int err;
77 
78 	err = init_stream(ff, &ff->rx_stream);
79 	if (err < 0)
80 		return err;
81 
82 	err = init_stream(ff, &ff->tx_stream);
83 	if (err < 0) {
84 		destroy_stream(ff, &ff->rx_stream);
85 		return err;
86 	}
87 
88 	err = amdtp_domain_init(&ff->domain);
89 	if (err < 0) {
90 		destroy_stream(ff, &ff->rx_stream);
91 		destroy_stream(ff, &ff->tx_stream);
92 	}
93 
94 	return err;
95 }
96 
97 /*
98  * This function should be called before starting streams or after stopping
99  * streams.
100  */
snd_ff_stream_destroy_duplex(struct snd_ff * ff)101 void snd_ff_stream_destroy_duplex(struct snd_ff *ff)
102 {
103 	amdtp_domain_destroy(&ff->domain);
104 
105 	destroy_stream(ff, &ff->rx_stream);
106 	destroy_stream(ff, &ff->tx_stream);
107 }
108 
snd_ff_stream_reserve_duplex(struct snd_ff * ff,unsigned int rate,unsigned int frames_per_period,unsigned int frames_per_buffer)109 int snd_ff_stream_reserve_duplex(struct snd_ff *ff, unsigned int rate,
110 				 unsigned int frames_per_period,
111 				 unsigned int frames_per_buffer)
112 {
113 	unsigned int curr_rate;
114 	enum snd_ff_clock_src src;
115 	int err;
116 
117 	err = ff->spec->protocol->get_clock(ff, &curr_rate, &src);
118 	if (err < 0)
119 		return err;
120 
121 	if (ff->substreams_counter == 0 || curr_rate != rate) {
122 		enum snd_ff_stream_mode mode;
123 		int i;
124 
125 		amdtp_domain_stop(&ff->domain);
126 		finish_session(ff);
127 
128 		fw_iso_resources_free(&ff->tx_resources);
129 		fw_iso_resources_free(&ff->rx_resources);
130 
131 		for (i = 0; i < CIP_SFC_COUNT; ++i) {
132 			if (amdtp_rate_table[i] == rate)
133 				break;
134 		}
135 		if (i >= CIP_SFC_COUNT)
136 			return -EINVAL;
137 
138 		err = snd_ff_stream_get_multiplier_mode(i, &mode);
139 		if (err < 0)
140 			return err;
141 
142 		err = amdtp_ff_set_parameters(&ff->tx_stream, rate,
143 					ff->spec->pcm_capture_channels[mode]);
144 		if (err < 0)
145 			return err;
146 
147 		err = amdtp_ff_set_parameters(&ff->rx_stream, rate,
148 					ff->spec->pcm_playback_channels[mode]);
149 		if (err < 0)
150 			return err;
151 
152 		err = ff->spec->protocol->allocate_resources(ff, rate);
153 		if (err < 0)
154 			return err;
155 
156 		err = amdtp_domain_set_events_per_period(&ff->domain,
157 					frames_per_period, frames_per_buffer);
158 		if (err < 0) {
159 			fw_iso_resources_free(&ff->tx_resources);
160 			fw_iso_resources_free(&ff->rx_resources);
161 			return err;
162 		}
163 	}
164 
165 	return 0;
166 }
167 
snd_ff_stream_start_duplex(struct snd_ff * ff,unsigned int rate)168 int snd_ff_stream_start_duplex(struct snd_ff *ff, unsigned int rate)
169 {
170 	int err;
171 
172 	if (ff->substreams_counter == 0)
173 		return 0;
174 
175 	if (amdtp_streaming_error(&ff->tx_stream) ||
176 	    amdtp_streaming_error(&ff->rx_stream)) {
177 		amdtp_domain_stop(&ff->domain);
178 		finish_session(ff);
179 	}
180 
181 	/*
182 	 * Regardless of current source of clock signal, drivers transfer some
183 	 * packets. Then, the device transfers packets.
184 	 */
185 	if (!amdtp_stream_running(&ff->rx_stream)) {
186 		int spd = fw_parent_device(ff->unit)->max_speed;
187 
188 		err = ff->spec->protocol->begin_session(ff, rate);
189 		if (err < 0)
190 			goto error;
191 
192 		err = amdtp_domain_add_stream(&ff->domain, &ff->rx_stream,
193 					      ff->rx_resources.channel, spd);
194 		if (err < 0)
195 			goto error;
196 
197 		err = amdtp_domain_add_stream(&ff->domain, &ff->tx_stream,
198 					      ff->tx_resources.channel, spd);
199 		if (err < 0)
200 			goto error;
201 
202 		// NOTE: The device doesn't transfer packets unless receiving any packet. The
203 		// sequence of tx packets includes cycle skip corresponding to empty packet or
204 		// NODATA packet in IEC 61883-1/6. The sequence of the number of data blocks per
205 		// packet is important for media clock recovery.
206 		err = amdtp_domain_start(&ff->domain, 0, true, true);
207 		if (err < 0)
208 			goto error;
209 
210 		if (!amdtp_domain_wait_ready(&ff->domain, READY_TIMEOUT_MS)) {
211 			err = -ETIMEDOUT;
212 			goto error;
213 		}
214 
215 		err = ff->spec->protocol->switch_fetching_mode(ff, true);
216 		if (err < 0)
217 			goto error;
218 	}
219 
220 	return 0;
221 error:
222 	amdtp_domain_stop(&ff->domain);
223 	finish_session(ff);
224 
225 	return err;
226 }
227 
snd_ff_stream_stop_duplex(struct snd_ff * ff)228 void snd_ff_stream_stop_duplex(struct snd_ff *ff)
229 {
230 	if (ff->substreams_counter == 0) {
231 		amdtp_domain_stop(&ff->domain);
232 		finish_session(ff);
233 
234 		fw_iso_resources_free(&ff->tx_resources);
235 		fw_iso_resources_free(&ff->rx_resources);
236 	}
237 }
238 
snd_ff_stream_update_duplex(struct snd_ff * ff)239 void snd_ff_stream_update_duplex(struct snd_ff *ff)
240 {
241 	amdtp_domain_stop(&ff->domain);
242 
243 	// The device discontinue to transfer packets.
244 	amdtp_stream_pcm_abort(&ff->tx_stream);
245 	amdtp_stream_pcm_abort(&ff->rx_stream);
246 }
247 
snd_ff_stream_lock_changed(struct snd_ff * ff)248 void snd_ff_stream_lock_changed(struct snd_ff *ff)
249 {
250 	ff->dev_lock_changed = true;
251 	wake_up(&ff->hwdep_wait);
252 }
253 
snd_ff_stream_lock_try(struct snd_ff * ff)254 int snd_ff_stream_lock_try(struct snd_ff *ff)
255 {
256 	int err;
257 
258 	spin_lock_irq(&ff->lock);
259 
260 	/* user land lock this */
261 	if (ff->dev_lock_count < 0) {
262 		err = -EBUSY;
263 		goto end;
264 	}
265 
266 	/* this is the first time */
267 	if (ff->dev_lock_count++ == 0)
268 		snd_ff_stream_lock_changed(ff);
269 	err = 0;
270 end:
271 	spin_unlock_irq(&ff->lock);
272 	return err;
273 }
274 
snd_ff_stream_lock_release(struct snd_ff * ff)275 void snd_ff_stream_lock_release(struct snd_ff *ff)
276 {
277 	spin_lock_irq(&ff->lock);
278 
279 	if (WARN_ON(ff->dev_lock_count <= 0))
280 		goto end;
281 	if (--ff->dev_lock_count == 0)
282 		snd_ff_stream_lock_changed(ff);
283 end:
284 	spin_unlock_irq(&ff->lock);
285 }
286