drivers/staging/line6/pcm.h

   1 /*
   2  * Line6 Linux USB driver - 0.9.1beta
   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 /*
  13         PCM interface to POD series devices.
  14 */
  15
  16 #ifndef PCM_H
  17 #define PCM_H
  18
  19 #include <sound/pcm.h>
  20
  21 #include "driver.h"
  22 #include "usbdefs.h"
  23
  24 /* number of URBs */
  25 #define LINE6_ISO_BUFFERS       2
  26
  27 /*
  28         number of USB frames per URB
  29         The Line6 Windows driver always transmits two frames per packet, but
  30         the Linux driver performs significantly better (i.e., lower latency)
  31         with only one frame per packet.
  32 */
  33 #define LINE6_ISO_PACKETS       1
  34
  35 /* in a "full speed" device (such as the PODxt Pro) this means 1ms */
  36 #define LINE6_ISO_INTERVAL      1
  37
  38 #ifdef CONFIG_LINE6_USB_IMPULSE_RESPONSE
  39 #define LINE6_IMPULSE_DEFAULT_PERIOD 100
  40 #endif
  41
  42 /*
  43         Get substream from Line6 PCM data structure
  44 */
  45 #define get_substream(line6pcm, stream) \
  46                 (line6pcm->pcm->streams[stream].substream)
  47
  48 /*
  49         PCM mode bits and masks.
  50         "ALSA": operations triggered by applications via ALSA
  51         "MONITOR": software monitoring
  52         "IMPULSE": optional impulse response operation
  53 */
  54 enum {
  55         /* individual bits: */
  56         BIT_PCM_ALSA_PLAYBACK,
  57         BIT_PCM_ALSA_CAPTURE,
  58         BIT_PCM_MONITOR_PLAYBACK,
  59         BIT_PCM_MONITOR_CAPTURE,
  60 #ifdef CONFIG_LINE6_USB_IMPULSE_RESPONSE
  61         BIT_PCM_IMPULSE_PLAYBACK,
  62         BIT_PCM_IMPULSE_CAPTURE,
  63 #endif
  64         BIT_PAUSE_PLAYBACK,
  65         BIT_PREPARED,
  66
  67         /* individual masks: */
  68 /* *INDENT-OFF* */
  69         MASK_PCM_ALSA_PLAYBACK    = 1 << BIT_PCM_ALSA_PLAYBACK,
  70         MASK_PCM_ALSA_CAPTURE     = 1 << BIT_PCM_ALSA_CAPTURE,
  71         MASK_PCM_MONITOR_PLAYBACK = 1 << BIT_PCM_MONITOR_PLAYBACK,
  72         MASK_PCM_MONITOR_CAPTURE  = 1 << BIT_PCM_MONITOR_CAPTURE,
  73 #ifdef CONFIG_LINE6_USB_IMPULSE_RESPONSE
  74         MASK_PCM_IMPULSE_PLAYBACK = 1 << BIT_PCM_IMPULSE_PLAYBACK,
  75         MASK_PCM_IMPULSE_CAPTURE  = 1 << BIT_PCM_IMPULSE_CAPTURE,
  76 #endif
  77         MASK_PAUSE_PLAYBACK       = 1 << BIT_PAUSE_PLAYBACK,
  78         MASK_PREPARED             = 1 << BIT_PREPARED,
  79 /* *INDENT-ON* */
  80
  81         /* combined masks (by operation): */
  82         MASK_PCM_ALSA = MASK_PCM_ALSA_PLAYBACK | MASK_PCM_ALSA_CAPTURE,
  83         MASK_PCM_MONITOR = MASK_PCM_MONITOR_PLAYBACK | MASK_PCM_MONITOR_CAPTURE,
  84 #ifdef CONFIG_LINE6_USB_IMPULSE_RESPONSE
  85         MASK_PCM_IMPULSE = MASK_PCM_IMPULSE_PLAYBACK | MASK_PCM_IMPULSE_CAPTURE,
  86 #endif
  87
  88         /* combined masks (by direction): */
  89 #ifdef CONFIG_LINE6_USB_IMPULSE_RESPONSE
  90         MASK_PLAYBACK =
  91             MASK_PCM_ALSA_PLAYBACK | MASK_PCM_MONITOR_PLAYBACK |
  92             MASK_PCM_IMPULSE_PLAYBACK,
  93         MASK_CAPTURE =
  94             MASK_PCM_ALSA_CAPTURE | MASK_PCM_MONITOR_CAPTURE |
  95             MASK_PCM_IMPULSE_CAPTURE
  96 #else
  97         MASK_PLAYBACK = MASK_PCM_ALSA_PLAYBACK | MASK_PCM_MONITOR_PLAYBACK,
  98         MASK_CAPTURE = MASK_PCM_ALSA_CAPTURE | MASK_PCM_MONITOR_CAPTURE
  99 #endif
 100 };
 101
 102 struct line6_pcm_properties {
 103         struct snd_pcm_hardware snd_line6_playback_hw, snd_line6_capture_hw;
 104         struct snd_pcm_hw_constraint_ratdens snd_line6_rates;
 105         int bytes_per_frame;
 106 };
 107
 108 struct snd_line6_pcm {
 109         /**
 110                  Pointer back to the Line6 driver data structure.
 111         */
 112         struct usb_line6 *line6;
 113
 114         /**
 115                  Properties.
 116         */
 117         struct line6_pcm_properties *properties;
 118
 119         /**
 120                  ALSA pcm stream
 121         */
 122         struct snd_pcm *pcm;
 123
 124         /**
 125                  URBs for audio playback.
 126         */
 127         struct urb *urb_audio_out[LINE6_ISO_BUFFERS];
 128
 129         /**
 130                  URBs for audio capture.
 131         */
 132         struct urb *urb_audio_in[LINE6_ISO_BUFFERS];
 133
 134         /**
 135                  Temporary buffer for playback.
 136                  Since the packet size is not known in advance, this buffer is
 137                  large enough to store maximum size packets.
 138         */
 139         unsigned char *buffer_out;
 140
 141         /**
 142                  Temporary buffer for capture.
 143                  Since the packet size is not known in advance, this buffer is
 144                  large enough to store maximum size packets.
 145         */
 146         unsigned char *buffer_in;
 147
 148         /**
 149                  Previously captured frame (for software monitoring).
 150         */
 151         unsigned char *prev_fbuf;
 152
 153         /**
 154                  Size of previously captured frame (for software monitoring).
 155         */
 156         int prev_fsize;
 157
 158         /**
 159                  Free frame position in the playback buffer.
 160         */
 161         snd_pcm_uframes_t pos_out;
 162
 163         /**
 164                  Count processed bytes for playback.
 165                  This is modulo period size (to determine when a period is
 166                  finished).
 167         */
 168         unsigned bytes_out;
 169
 170         /**
 171                  Counter to create desired playback sample rate.
 172         */
 173         unsigned count_out;
 174
 175         /**
 176                  Playback period size in bytes
 177         */
 178         unsigned period_out;
 179
 180         /**
 181                  Processed frame position in the playback buffer.
 182                  The contents of the output ring buffer have been consumed by
 183                  the USB subsystem (i.e., sent to the USB device) up to this
 184                  position.
 185         */
 186         snd_pcm_uframes_t pos_out_done;
 187
 188         /**
 189                  Count processed bytes for capture.
 190                  This is modulo period size (to determine when a period is
 191                  finished).
 192         */
 193         unsigned bytes_in;
 194
 195         /**
 196                  Counter to create desired capture sample rate.
 197         */
 198         unsigned count_in;
 199
 200         /**
 201                  Capture period size in bytes
 202         */
 203         unsigned period_in;
 204
 205         /**
 206                  Processed frame position in the capture buffer.
 207                  The contents of the output ring buffer have been consumed by
 208                  the USB subsystem (i.e., sent to the USB device) up to this
 209                  position.
 210         */
 211         snd_pcm_uframes_t pos_in_done;
 212
 213         /**
 214                  Bit mask of active playback URBs.
 215         */
 216         unsigned long active_urb_out;
 217
 218         /**
 219                  Maximum size of USB packet.
 220         */
 221         int max_packet_size;
 222
 223         /**
 224                  USB endpoint for listening to audio data.
 225         */
 226         int ep_audio_read;
 227
 228         /**
 229                  USB endpoint for writing audio data.
 230         */
 231         int ep_audio_write;
 232
 233         /**
 234                  Bit mask of active capture URBs.
 235         */
 236         unsigned long active_urb_in;
 237
 238         /**
 239                  Bit mask of playback URBs currently being unlinked.
 240         */
 241         unsigned long unlink_urb_out;
 242
 243         /**
 244                  Bit mask of capture URBs currently being unlinked.
 245         */
 246         unsigned long unlink_urb_in;
 247
 248         /**
 249                  Spin lock to protect updates of the playback buffer positions (not
 250                  contents!)
 251         */
 252         spinlock_t lock_audio_out;
 253
 254         /**
 255                  Spin lock to protect updates of the capture buffer positions (not
 256                  contents!)
 257         */
 258         spinlock_t lock_audio_in;
 259
 260         /**
 261                  Spin lock to protect trigger.
 262         */
 263         spinlock_t lock_trigger;
 264
 265         /**
 266                  PCM playback volume (left and right).
 267         */
 268         int volume_playback[2];
 269
 270         /**
 271                  PCM monitor volume.
 272         */
 273         int volume_monitor;
 274
 275 #ifdef CONFIG_LINE6_USB_IMPULSE_RESPONSE
 276         /**
 277                  Volume of impulse response test signal (if zero, test is disabled).
 278         */
 279         int impulse_volume;
 280
 281         /**
 282                  Period of impulse response test signal.
 283         */
 284         int impulse_period;
 285
 286         /**
 287                  Counter for impulse response test signal.
 288         */
 289         int impulse_count;
 290 #endif
 291
 292         /**
 293                  Several status bits (see BIT_*).
 294         */
 295         unsigned long flags;
 296
 297         int last_frame_in, last_frame_out;
 298 };
 299
 300 extern int line6_init_pcm(struct usb_line6 *line6,
 301                           struct line6_pcm_properties *properties);
 302 extern int snd_line6_trigger(struct snd_pcm_substream *substream, int cmd);
 303 extern int snd_line6_prepare(struct snd_pcm_substream *substream);
 304 extern void line6_pcm_disconnect(struct snd_line6_pcm *line6pcm);
 305 extern int line6_pcm_start(struct snd_line6_pcm *line6pcm, int channels);
 306 extern int line6_pcm_stop(struct snd_line6_pcm *line6pcm, int channels);
 307
 308 #define PRINT_FRAME_DIFF(op) {                                          \
 309         static int diff_prev = 1000;                                    \
 310         int diff = line6pcm->last_frame_out - line6pcm->last_frame_in;  \
 311         if ((diff != diff_prev) && (abs(diff) < 100)) {                 \
 312                 printk(KERN_INFO "%s frame diff = %d\n", op, diff);     \
 313                 diff_prev = diff;                                       \
 314         }                                                               \
 315 }
 316
 317 #endif