1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Line 6 Linux USB driver
4 *
5 * Copyright (C) 2004-2010 Markus Grabner (grabner@icg.tugraz.at)
6 */
7
8 #include <linux/slab.h>
9 #include <sound/core.h>
10 #include <sound/pcm.h>
11 #include <sound/pcm_params.h>
12
13 #include "capture.h"
14 #include "driver.h"
15 #include "pcm.h"
16 #include "playback.h"
17
18 /*
19 Software stereo volume control.
20 */
21 static void change_volume(struct urb *urb_out, int volume[],
22 int bytes_per_frame)
23 {
24 int chn = 0;
25
26 if (volume[0] == 256 && volume[1] == 256)
27 return; /* maximum volume - no change */
28
29 if (bytes_per_frame == 4) {
30 __le16 *p, *buf_end;
31
32 p = (__le16 *)urb_out->transfer_buffer;
33 buf_end = p + urb_out->transfer_buffer_length / sizeof(*p);
34
35 for (; p < buf_end; ++p) {
36 short pv = le16_to_cpu(*p);
37 int val = (pv * volume[chn & 1]) >> 8;
38 pv = clamp(val, -0x8000, 0x7fff);
39 *p = cpu_to_le16(pv);
40 ++chn;
41 }
42 } else if (bytes_per_frame == 6) {
43 unsigned char *p, *buf_end;
44
45 p = (unsigned char *)urb_out->transfer_buffer;
46 buf_end = p + urb_out->transfer_buffer_length;
47
48 for (; p < buf_end; p += 3) {
49 int val;
50
51 val = p[0] + (p[1] << 8) + ((signed char)p[2] << 16);
52 val = (val * volume[chn & 1]) >> 8;
53 val = clamp(val, -0x800000, 0x7fffff);
54 p[0] = val;
55 p[1] = val >> 8;
56 p[2] = val >> 16;
57 ++chn;
58 }
59 }
60 }
61
62 /*
63 Create signal for impulse response test.
64 */
65 static void create_impulse_test_signal(struct snd_line6_pcm *line6pcm,
66 struct urb *urb_out, int bytes_per_frame)
67 {
68 int frames = urb_out->transfer_buffer_length / bytes_per_frame;
69
70 if (bytes_per_frame == 4) {
71 int i;
72 short *pi = (short *)line6pcm->prev_fbuf;
73 short *po = (short *)urb_out->transfer_buffer;
74
75 for (i = 0; i < frames; ++i) {
76 po[0] = pi[0];
77 po[1] = 0;
78 pi += 2;
79 po += 2;
80 }
81 } else if (bytes_per_frame == 6) {
82 int i, j;
83 unsigned char *pi = line6pcm->prev_fbuf;
84 unsigned char *po = urb_out->transfer_buffer;
85
86 for (i = 0; i < frames; ++i) {
87 for (j = 0; j < bytes_per_frame / 2; ++j)
88 po[j] = pi[j];
89
90 for (; j < bytes_per_frame; ++j)
91 po[j] = 0;
92
93 pi += bytes_per_frame;
94 po += bytes_per_frame;
95 }
96 }
97 if (--line6pcm->impulse_count <= 0) {
98 ((unsigned char *)(urb_out->transfer_buffer))[bytes_per_frame -
99 1] =
100 line6pcm->impulse_volume;
101 line6pcm->impulse_count = line6pcm->impulse_period;
102 }
103 }
104
105 /*
106 Add signal to buffer for software monitoring.
107 */
108 static void add_monitor_signal(struct urb *urb_out, unsigned char *signal,
109 int volume, int bytes_per_frame)
110 {
111 if (volume == 0)
112 return; /* zero volume - no change */
113
114 if (bytes_per_frame == 4) {
115 __le16 *pi, *po, *buf_end;
116
117 pi = (__le16 *)signal;
118 po = (__le16 *)urb_out->transfer_buffer;
119 buf_end = po + urb_out->transfer_buffer_length / sizeof(*po);
120
121 for (; po < buf_end; ++pi, ++po) {
122 short pov = le16_to_cpu(*po);
123 short piv = le16_to_cpu(*pi);
124 int val = pov + ((piv * volume) >> 8);
125 pov = clamp(val, -0x8000, 0x7fff);
126 *po = cpu_to_le16(pov);
127 }
128 }
129
130 /*
131 We don't need to handle devices with 6 bytes per frame here
132 since they all support hardware monitoring.
133 */
134 }
135
136 /*
137 Find a free URB, prepare audio data, and submit URB.
138 must be called in line6pcm->out.lock context
139 */
140 static int submit_audio_out_urb(struct snd_line6_pcm *line6pcm)
141 {
142 int index;
143 int i, urb_size, urb_frames;
144 int ret;
145 const int bytes_per_frame =
146 line6pcm->properties->bytes_per_channel *
147 line6pcm->properties->playback_hw.channels_max;
148 const int frame_increment =
149 line6pcm->properties->rates.rats[0].num_min;
150 const int frame_factor =
151 line6pcm->properties->rates.rats[0].den *
152 (line6pcm->line6->intervals_per_second / LINE6_ISO_INTERVAL);
153 struct urb *urb_out;
154
155 index = find_first_zero_bit(&line6pcm->out.active_urbs,
156 line6pcm->line6->iso_buffers);
157
158 if (index < 0 || index >= line6pcm->line6->iso_buffers) {
159 dev_err(line6pcm->line6->ifcdev, "no free URB found\n");
160 return -EINVAL;
161 }
162
163 urb_out = line6pcm->out.urbs[index];
164 urb_size = 0;
165
166 /* TODO: this may not work for LINE6_ISO_PACKETS != 1 */
167 for (i = 0; i < LINE6_ISO_PACKETS; ++i) {
168 /* compute frame size for given sampling rate */
169 int fsize = 0;
170 struct usb_iso_packet_descriptor *fout =
171 &urb_out->iso_frame_desc[i];
172
173 fsize = line6pcm->prev_fsize;
174 if (fsize == 0) {
175 int n;
176
177 line6pcm->out.count += frame_increment;
178 n = line6pcm->out.count / frame_factor;
179 line6pcm->out.count -= n * frame_factor;
180 fsize = n;
181 }
182
183 fsize *= bytes_per_frame;
184
185 fout->offset = urb_size;
186 fout->length = fsize;
187 urb_size += fsize;
188 }
189
190 if (urb_size == 0) {
191 /* can't determine URB size */
192 dev_err(line6pcm->line6->ifcdev, "driver bug: urb_size = 0\n");
193 return -EINVAL;
194 }
195
196 urb_frames = urb_size / bytes_per_frame;
197 urb_out->transfer_buffer =
198 line6pcm->out.buffer +
199 index * LINE6_ISO_PACKETS * line6pcm->max_packet_size_out;
200 urb_out->transfer_buffer_length = urb_size;
201 urb_out->context = line6pcm;
202
203 if (test_bit(LINE6_STREAM_PCM, &line6pcm->out.running) &&
204 !test_bit(LINE6_FLAG_PAUSE_PLAYBACK, &line6pcm->flags)) {
205 struct snd_pcm_runtime *runtime =
206 get_substream(line6pcm, SNDRV_PCM_STREAM_PLAYBACK)->runtime;
207
208 if (line6pcm->out.pos + urb_frames > runtime->buffer_size) {
209 /*
210 The transferred area goes over buffer boundary,
211 copy the data to the temp buffer.
212 */
213 int len;
214
215 len = runtime->buffer_size - line6pcm->out.pos;
216
217 if (len > 0) {
218 memcpy(urb_out->transfer_buffer,
219 runtime->dma_area +
220 line6pcm->out.pos * bytes_per_frame,
221 len * bytes_per_frame);
222 memcpy(urb_out->transfer_buffer +
223 len * bytes_per_frame, runtime->dma_area,
224 (urb_frames - len) * bytes_per_frame);
225 } else
226 dev_err(line6pcm->line6->ifcdev, "driver bug: len = %d\n",
227 len);
228 } else {
229 memcpy(urb_out->transfer_buffer,
230 runtime->dma_area +
231 line6pcm->out.pos * bytes_per_frame,
232 urb_out->transfer_buffer_length);
233 }
234
235 line6pcm->out.pos += urb_frames;
236 if (line6pcm->out.pos >= runtime->buffer_size)
237 line6pcm->out.pos -= runtime->buffer_size;
238
239 change_volume(urb_out, line6pcm->volume_playback,
240 bytes_per_frame);
241 } else {
242 memset(urb_out->transfer_buffer, 0,
243 urb_out->transfer_buffer_length);
244 }
245
246 spin_lock_nested(&line6pcm->in.lock, SINGLE_DEPTH_NESTING);
247 if (line6pcm->prev_fbuf) {
248 if (test_bit(LINE6_STREAM_IMPULSE, &line6pcm->out.running)) {
249 create_impulse_test_signal(line6pcm, urb_out,
250 bytes_per_frame);
251 if (test_bit(LINE6_STREAM_PCM, &line6pcm->in.running)) {
252 line6_capture_copy(line6pcm,
253 urb_out->transfer_buffer,
254 urb_out->
255 transfer_buffer_length);
256 line6_capture_check_period(line6pcm,
257 urb_out->transfer_buffer_length);
258 }
259 } else {
260 if (!(line6pcm->line6->properties->capabilities & LINE6_CAP_HWMON)
261 && line6pcm->out.running && line6pcm->in.running)
262 add_monitor_signal(urb_out, line6pcm->prev_fbuf,
263 line6pcm->volume_monitor,
264 bytes_per_frame);
265 }
266 line6pcm->prev_fbuf = NULL;
267 line6pcm->prev_fsize = 0;
268 }
269 spin_unlock(&line6pcm->in.lock);
270
271 ret = usb_submit_urb(urb_out, GFP_ATOMIC);
272
273 if (ret == 0)
274 set_bit(index, &line6pcm->out.active_urbs);
275 else
276 dev_err(line6pcm->line6->ifcdev,
277 "URB out #%d submission failed (%d)\n", index, ret);
278
279 return 0;
280 }
281
282 /*
283 Submit all currently available playback URBs.
284 must be called in line6pcm->out.lock context
285 */
286 int line6_submit_audio_out_all_urbs(struct snd_line6_pcm *line6pcm)
287 {
288 int ret = 0, i;
289
290 for (i = 0; i < line6pcm->line6->iso_buffers; ++i) {
291 ret = submit_audio_out_urb(line6pcm);
292 if (ret < 0)
293 break;
294 }
295
296 return ret;
297 }
298
299 /*
300 Callback for completed playback URB.
301 */
302 static void audio_out_callback(struct urb *urb)
303 {
304 int i, index, length = 0, shutdown = 0;
305 unsigned long flags;
306 struct snd_line6_pcm *line6pcm = (struct snd_line6_pcm *)urb->context;
307 struct snd_pcm_substream *substream =
308 get_substream(line6pcm, SNDRV_PCM_STREAM_PLAYBACK);
309 const int bytes_per_frame =
310 line6pcm->properties->bytes_per_channel *
311 line6pcm->properties->playback_hw.channels_max;
312
313 #if USE_CLEAR_BUFFER_WORKAROUND
314 memset(urb->transfer_buffer, 0, urb->transfer_buffer_length);
315 #endif
316
317 line6pcm->out.last_frame = urb->start_frame;
318
319 /* find index of URB */
320 for (index = 0; index < line6pcm->line6->iso_buffers; index++)
321 if (urb == line6pcm->out.urbs[index])
322 break;
323
324 if (index >= line6pcm->line6->iso_buffers)
325 return; /* URB has been unlinked asynchronously */
326
327 for (i = 0; i < LINE6_ISO_PACKETS; i++)
328 length += urb->iso_frame_desc[i].length;
329
330 spin_lock_irqsave(&line6pcm->out.lock, flags);
331
332 if (test_bit(LINE6_STREAM_PCM, &line6pcm->out.running)) {
333 struct snd_pcm_runtime *runtime = substream->runtime;
334
335 line6pcm->out.pos_done +=
336 length / bytes_per_frame;
337
338 if (line6pcm->out.pos_done >= runtime->buffer_size)
339 line6pcm->out.pos_done -= runtime->buffer_size;
340 }
341
342 clear_bit(index, &line6pcm->out.active_urbs);
343
344 for (i = 0; i < LINE6_ISO_PACKETS; i++)
345 if (urb->iso_frame_desc[i].status == -EXDEV) {
346 shutdown = 1;
347 break;
348 }
349
350 if (test_and_clear_bit(index, &line6pcm->out.unlink_urbs))
351 shutdown = 1;
352
353 if (!shutdown) {
354 submit_audio_out_urb(line6pcm);
355
356 if (test_bit(LINE6_STREAM_PCM, &line6pcm->out.running)) {
357 line6pcm->out.bytes += length;
358 if (line6pcm->out.bytes >= line6pcm->out.period) {
359 line6pcm->out.bytes %= line6pcm->out.period;
360 spin_unlock(&line6pcm->out.lock);
361 snd_pcm_period_elapsed(substream);
362 spin_lock(&line6pcm->out.lock);
363 }
364 }
365 }
366 spin_unlock_irqrestore(&line6pcm->out.lock, flags);
367 }
368
369 /* open playback callback */
370 static int snd_line6_playback_open(struct snd_pcm_substream *substream)
371 {
372 int err;
373 struct snd_pcm_runtime *runtime = substream->runtime;
374 struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
375
376 err = snd_pcm_hw_constraint_ratdens(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
377 &line6pcm->properties->rates);
378 if (err < 0)
379 return err;
380
381 runtime->hw = line6pcm->properties->playback_hw;
382 return 0;
383 }
384
385 /* close playback callback */
386 static int snd_line6_playback_close(struct snd_pcm_substream *substream)
387 {
388 return 0;
389 }
390
391 /* playback operators */
392 const struct snd_pcm_ops snd_line6_playback_ops = {
393 .open = snd_line6_playback_open,
394 .close = snd_line6_playback_close,
395 .hw_params = snd_line6_hw_params,
396 .hw_free = snd_line6_hw_free,
397 .prepare = snd_line6_prepare,
398 .trigger = snd_line6_trigger,
399 .pointer = snd_line6_pointer,
400 };
401
402 int line6_create_audio_out_urbs(struct snd_line6_pcm *line6pcm)
403 {
404 struct usb_line6 *line6 = line6pcm->line6;
405 int i;
406
407 line6pcm->out.urbs = kcalloc(line6->iso_buffers, sizeof(struct urb *),
408 GFP_KERNEL);
409 if (line6pcm->out.urbs == NULL)
410 return -ENOMEM;
411
412 /* create audio URBs and fill in constant values: */
413 for (i = 0; i < line6->iso_buffers; ++i) {
414 struct urb *urb;
415
416 /* URB for audio out: */
417 urb = line6pcm->out.urbs[i] =
418 usb_alloc_urb(LINE6_ISO_PACKETS, GFP_KERNEL);
419
420 if (urb == NULL)
421 return -ENOMEM;
422
423 urb->dev = line6->usbdev;
424 urb->pipe =
425 usb_sndisocpipe(line6->usbdev,
426 line6->properties->ep_audio_w &
427 USB_ENDPOINT_NUMBER_MASK);
428 urb->transfer_flags = URB_ISO_ASAP;
429 urb->start_frame = -1;
430 urb->number_of_packets = LINE6_ISO_PACKETS;
431 urb->interval = LINE6_ISO_INTERVAL;
432 urb->error_count = 0;
433 urb->complete = audio_out_callback;
434 if (usb_urb_ep_type_check(urb))
435 return -EINVAL;
436 }
437
438 return 0;
439 }
440
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