1 /* 2 * Line 6 Linux USB driver 3 * 4 * Copyright (C) 2004-2010 Markus Grabner (grabner@icg.tugraz.at) 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License as 8 * published by the Free Software Foundation, version 2. 9 * 10 */ 11 12 #include <linux/slab.h> 13 #include <sound/core.h> 14 #include <sound/pcm.h> 15 #include <sound/pcm_params.h> 16 17 #include "capture.h" 18 #include "driver.h" 19 #include "pcm.h" 20 #include "playback.h" 21 22 /* 23 Software stereo volume control. 24 */ 25 static void change_volume(struct urb *urb_out, int volume[], 26 int bytes_per_frame) 27 { 28 int chn = 0; 29 30 if (volume[0] == 256 && volume[1] == 256) 31 return; /* maximum volume - no change */ 32 33 if (bytes_per_frame == 4) { 34 short *p, *buf_end; 35 36 p = (short *)urb_out->transfer_buffer; 37 buf_end = p + urb_out->transfer_buffer_length / sizeof(*p); 38 39 for (; p < buf_end; ++p) { 40 int val = (*p * volume[chn & 1]) >> 8; 41 *p = clamp(val, 0x7fff, -0x8000); 42 ++chn; 43 } 44 } else if (bytes_per_frame == 6) { 45 unsigned char *p, *buf_end; 46 47 p = (unsigned char *)urb_out->transfer_buffer; 48 buf_end = p + urb_out->transfer_buffer_length; 49 50 for (; p < buf_end; p += 3) { 51 int val; 52 53 val = p[0] + (p[1] << 8) + ((signed char)p[2] << 16); 54 val = (val * volume[chn & 1]) >> 8; 55 val = clamp(val, 0x7fffff, -0x800000); 56 p[0] = val; 57 p[1] = val >> 8; 58 p[2] = val >> 16; 59 ++chn; 60 } 61 } 62 } 63 64 /* 65 Create signal for impulse response test. 66 */ 67 static void create_impulse_test_signal(struct snd_line6_pcm *line6pcm, 68 struct urb *urb_out, int bytes_per_frame) 69 { 70 int frames = urb_out->transfer_buffer_length / bytes_per_frame; 71 72 if (bytes_per_frame == 4) { 73 int i; 74 short *pi = (short *)line6pcm->prev_fbuf; 75 short *po = (short *)urb_out->transfer_buffer; 76 77 for (i = 0; i < frames; ++i) { 78 po[0] = pi[0]; 79 po[1] = 0; 80 pi += 2; 81 po += 2; 82 } 83 } else if (bytes_per_frame == 6) { 84 int i, j; 85 unsigned char *pi = line6pcm->prev_fbuf; 86 unsigned char *po = urb_out->transfer_buffer; 87 88 for (i = 0; i < frames; ++i) { 89 for (j = 0; j < bytes_per_frame / 2; ++j) 90 po[j] = pi[j]; 91 92 for (; j < bytes_per_frame; ++j) 93 po[j] = 0; 94 95 pi += bytes_per_frame; 96 po += bytes_per_frame; 97 } 98 } 99 if (--line6pcm->impulse_count <= 0) { 100 ((unsigned char *)(urb_out->transfer_buffer))[bytes_per_frame - 101 1] = 102 line6pcm->impulse_volume; 103 line6pcm->impulse_count = line6pcm->impulse_period; 104 } 105 } 106 107 /* 108 Add signal to buffer for software monitoring. 109 */ 110 static void add_monitor_signal(struct urb *urb_out, unsigned char *signal, 111 int volume, int bytes_per_frame) 112 { 113 if (volume == 0) 114 return; /* zero volume - no change */ 115 116 if (bytes_per_frame == 4) { 117 short *pi, *po, *buf_end; 118 119 pi = (short *)signal; 120 po = (short *)urb_out->transfer_buffer; 121 buf_end = po + urb_out->transfer_buffer_length / sizeof(*po); 122 123 for (; po < buf_end; ++pi, ++po) { 124 int val = *po + ((*pi * volume) >> 8); 125 *po = clamp(val, 0x7fff, -0x8000); 126 } 127 } 128 129 /* 130 We don't need to handle devices with 6 bytes per frame here 131 since they all support hardware monitoring. 132 */ 133 } 134 135 /* 136 Find a free URB, prepare audio data, and submit URB. 137 must be called in line6pcm->out.lock context 138 */ 139 static int submit_audio_out_urb(struct snd_line6_pcm *line6pcm) 140 { 141 int index; 142 int i, urb_size, urb_frames; 143 int ret; 144 const int bytes_per_frame = line6pcm->properties->bytes_per_frame; 145 const int frame_increment = 146 line6pcm->properties->snd_line6_rates.rats[0].num_min; 147 const int frame_factor = 148 line6pcm->properties->snd_line6_rates.rats[0].den * 149 (USB_INTERVALS_PER_SECOND / LINE6_ISO_INTERVAL); 150 struct urb *urb_out; 151 152 index = 153 find_first_zero_bit(&line6pcm->out.active_urbs, LINE6_ISO_BUFFERS); 154 155 if (index < 0 || index >= LINE6_ISO_BUFFERS) { 156 dev_err(line6pcm->line6->ifcdev, "no free URB found\n"); 157 return -EINVAL; 158 } 159 160 urb_out = line6pcm->out.urbs[index]; 161 urb_size = 0; 162 163 for (i = 0; i < LINE6_ISO_PACKETS; ++i) { 164 /* compute frame size for given sampling rate */ 165 int fsize = 0; 166 struct usb_iso_packet_descriptor *fout = 167 &urb_out->iso_frame_desc[i]; 168 169 fsize = line6pcm->prev_fsize; 170 if (fsize == 0) { 171 int n; 172 173 line6pcm->out.count += frame_increment; 174 n = line6pcm->out.count / frame_factor; 175 line6pcm->out.count -= n * frame_factor; 176 fsize = n * bytes_per_frame; 177 } 178 179 fout->offset = urb_size; 180 fout->length = fsize; 181 urb_size += fsize; 182 } 183 184 if (urb_size == 0) { 185 /* can't determine URB size */ 186 dev_err(line6pcm->line6->ifcdev, "driver bug: urb_size = 0\n"); 187 return -EINVAL; 188 } 189 190 urb_frames = urb_size / bytes_per_frame; 191 urb_out->transfer_buffer = 192 line6pcm->out.buffer + 193 index * LINE6_ISO_PACKETS * line6pcm->max_packet_size; 194 urb_out->transfer_buffer_length = urb_size; 195 urb_out->context = line6pcm; 196 197 if (test_bit(LINE6_STREAM_PCM, &line6pcm->out.running) && 198 !test_bit(LINE6_FLAG_PAUSE_PLAYBACK, &line6pcm->flags)) { 199 struct snd_pcm_runtime *runtime = 200 get_substream(line6pcm, SNDRV_PCM_STREAM_PLAYBACK)->runtime; 201 202 if (line6pcm->out.pos + urb_frames > runtime->buffer_size) { 203 /* 204 The transferred area goes over buffer boundary, 205 copy the data to the temp buffer. 206 */ 207 int len; 208 209 len = runtime->buffer_size - line6pcm->out.pos; 210 211 if (len > 0) { 212 memcpy(urb_out->transfer_buffer, 213 runtime->dma_area + 214 line6pcm->out.pos * bytes_per_frame, 215 len * bytes_per_frame); 216 memcpy(urb_out->transfer_buffer + 217 len * bytes_per_frame, runtime->dma_area, 218 (urb_frames - len) * bytes_per_frame); 219 } else 220 dev_err(line6pcm->line6->ifcdev, "driver bug: len = %d\n", 221 len); 222 } else { 223 memcpy(urb_out->transfer_buffer, 224 runtime->dma_area + 225 line6pcm->out.pos * bytes_per_frame, 226 urb_out->transfer_buffer_length); 227 } 228 229 line6pcm->out.pos += urb_frames; 230 if (line6pcm->out.pos >= runtime->buffer_size) 231 line6pcm->out.pos -= runtime->buffer_size; 232 233 change_volume(urb_out, line6pcm->volume_playback, 234 bytes_per_frame); 235 } else { 236 memset(urb_out->transfer_buffer, 0, 237 urb_out->transfer_buffer_length); 238 } 239 240 spin_lock_nested(&line6pcm->in.lock, SINGLE_DEPTH_NESTING); 241 if (line6pcm->prev_fbuf) { 242 if (test_bit(LINE6_STREAM_IMPULSE, &line6pcm->out.running)) { 243 create_impulse_test_signal(line6pcm, urb_out, 244 bytes_per_frame); 245 if (test_bit(LINE6_STREAM_PCM, &line6pcm->in.running)) { 246 line6_capture_copy(line6pcm, 247 urb_out->transfer_buffer, 248 urb_out-> 249 transfer_buffer_length); 250 line6_capture_check_period(line6pcm, 251 urb_out->transfer_buffer_length); 252 } 253 } else { 254 if (!(line6pcm->line6->properties->capabilities & LINE6_CAP_HWMON) 255 && line6pcm->out.running && line6pcm->in.running) 256 add_monitor_signal(urb_out, line6pcm->prev_fbuf, 257 line6pcm->volume_monitor, 258 bytes_per_frame); 259 } 260 line6pcm->prev_fbuf = NULL; 261 line6pcm->prev_fsize = 0; 262 } 263 spin_unlock(&line6pcm->in.lock); 264 265 ret = usb_submit_urb(urb_out, GFP_ATOMIC); 266 267 if (ret == 0) 268 set_bit(index, &line6pcm->out.active_urbs); 269 else 270 dev_err(line6pcm->line6->ifcdev, 271 "URB out #%d submission failed (%d)\n", index, ret); 272 273 return 0; 274 } 275 276 /* 277 Submit all currently available playback URBs. 278 must be called in line6pcm->out.lock context 279 */ 280 int line6_submit_audio_out_all_urbs(struct snd_line6_pcm *line6pcm) 281 { 282 int ret = 0, i; 283 284 for (i = 0; i < LINE6_ISO_BUFFERS; ++i) { 285 ret = submit_audio_out_urb(line6pcm); 286 if (ret < 0) 287 break; 288 } 289 290 return ret; 291 } 292 293 /* 294 Callback for completed playback URB. 295 */ 296 static void audio_out_callback(struct urb *urb) 297 { 298 int i, index, length = 0, shutdown = 0; 299 unsigned long flags; 300 struct snd_line6_pcm *line6pcm = (struct snd_line6_pcm *)urb->context; 301 struct snd_pcm_substream *substream = 302 get_substream(line6pcm, SNDRV_PCM_STREAM_PLAYBACK); 303 304 #if USE_CLEAR_BUFFER_WORKAROUND 305 memset(urb->transfer_buffer, 0, urb->transfer_buffer_length); 306 #endif 307 308 line6pcm->out.last_frame = urb->start_frame; 309 310 /* find index of URB */ 311 for (index = 0; index < LINE6_ISO_BUFFERS; index++) 312 if (urb == line6pcm->out.urbs[index]) 313 break; 314 315 if (index >= LINE6_ISO_BUFFERS) 316 return; /* URB has been unlinked asynchronously */ 317 318 for (i = 0; i < LINE6_ISO_PACKETS; i++) 319 length += urb->iso_frame_desc[i].length; 320 321 spin_lock_irqsave(&line6pcm->out.lock, flags); 322 323 if (test_bit(LINE6_STREAM_PCM, &line6pcm->out.running)) { 324 struct snd_pcm_runtime *runtime = substream->runtime; 325 326 line6pcm->out.pos_done += 327 length / line6pcm->properties->bytes_per_frame; 328 329 if (line6pcm->out.pos_done >= runtime->buffer_size) 330 line6pcm->out.pos_done -= runtime->buffer_size; 331 } 332 333 clear_bit(index, &line6pcm->out.active_urbs); 334 335 for (i = 0; i < LINE6_ISO_PACKETS; i++) 336 if (urb->iso_frame_desc[i].status == -EXDEV) { 337 shutdown = 1; 338 break; 339 } 340 341 if (test_and_clear_bit(index, &line6pcm->out.unlink_urbs)) 342 shutdown = 1; 343 344 if (!shutdown) { 345 submit_audio_out_urb(line6pcm); 346 347 if (test_bit(LINE6_STREAM_PCM, &line6pcm->out.running)) { 348 line6pcm->out.bytes += length; 349 if (line6pcm->out.bytes >= line6pcm->out.period) { 350 line6pcm->out.bytes %= line6pcm->out.period; 351 spin_unlock(&line6pcm->out.lock); 352 snd_pcm_period_elapsed(substream); 353 spin_lock(&line6pcm->out.lock); 354 } 355 } 356 } 357 spin_unlock_irqrestore(&line6pcm->out.lock, flags); 358 } 359 360 /* open playback callback */ 361 static int snd_line6_playback_open(struct snd_pcm_substream *substream) 362 { 363 int err; 364 struct snd_pcm_runtime *runtime = substream->runtime; 365 struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream); 366 367 err = snd_pcm_hw_constraint_ratdens(runtime, 0, SNDRV_PCM_HW_PARAM_RATE, 368 (&line6pcm-> 369 properties->snd_line6_rates)); 370 if (err < 0) 371 return err; 372 373 runtime->hw = line6pcm->properties->snd_line6_playback_hw; 374 return 0; 375 } 376 377 /* close playback callback */ 378 static int snd_line6_playback_close(struct snd_pcm_substream *substream) 379 { 380 return 0; 381 } 382 383 /* playback operators */ 384 struct snd_pcm_ops snd_line6_playback_ops = { 385 .open = snd_line6_playback_open, 386 .close = snd_line6_playback_close, 387 .ioctl = snd_pcm_lib_ioctl, 388 .hw_params = snd_line6_hw_params, 389 .hw_free = snd_line6_hw_free, 390 .prepare = snd_line6_prepare, 391 .trigger = snd_line6_trigger, 392 .pointer = snd_line6_pointer, 393 }; 394 395 int line6_create_audio_out_urbs(struct snd_line6_pcm *line6pcm) 396 { 397 struct usb_line6 *line6 = line6pcm->line6; 398 int i; 399 400 /* create audio URBs and fill in constant values: */ 401 for (i = 0; i < LINE6_ISO_BUFFERS; ++i) { 402 struct urb *urb; 403 404 /* URB for audio out: */ 405 urb = line6pcm->out.urbs[i] = 406 usb_alloc_urb(LINE6_ISO_PACKETS, GFP_KERNEL); 407 408 if (urb == NULL) 409 return -ENOMEM; 410 411 urb->dev = line6->usbdev; 412 urb->pipe = 413 usb_sndisocpipe(line6->usbdev, 414 line6->properties->ep_audio_w & 415 USB_ENDPOINT_NUMBER_MASK); 416 urb->transfer_flags = URB_ISO_ASAP; 417 urb->start_frame = -1; 418 urb->number_of_packets = LINE6_ISO_PACKETS; 419 urb->interval = LINE6_ISO_INTERVAL; 420 urb->error_count = 0; 421 urb->complete = audio_out_callback; 422 } 423 424 return 0; 425 } 426