sound/usb/line6/capture.c

   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
  17 /*
  18         Find a free URB and submit it.
  19         must be called in line6pcm->in.lock context
  20 */
  21 static int submit_audio_in_urb(struct snd_line6_pcm *line6pcm)
  22 {
  23         int index;
  24         int i, urb_size;
  25         int ret;
  26         struct urb *urb_in;
  27
  28         index = find_first_zero_bit(&line6pcm->in.active_urbs,
  29                                     line6pcm->line6->iso_buffers);
  30
  31         if (index < 0 || index >= line6pcm->line6->iso_buffers) {
  32                 dev_err(line6pcm->line6->ifcdev, "no free URB found\n");
  33                 return -EINVAL;
  34         }
  35
  36         urb_in = line6pcm->in.urbs[index];
  37         urb_size = 0;
  38
  39         for (i = 0; i < LINE6_ISO_PACKETS; ++i) {
  40                 struct usb_iso_packet_descriptor *fin =
  41                     &urb_in->iso_frame_desc[i];
  42                 fin->offset = urb_size;
  43                 fin->length = line6pcm->max_packet_size_in;
  44                 urb_size += line6pcm->max_packet_size_in;
  45         }
  46
  47         urb_in->transfer_buffer =
  48             line6pcm->in.buffer +
  49             index * LINE6_ISO_PACKETS * line6pcm->max_packet_size_in;
  50         urb_in->transfer_buffer_length = urb_size;
  51         urb_in->context = line6pcm;
  52
  53         ret = usb_submit_urb(urb_in, GFP_ATOMIC);
  54
  55         if (ret == 0)
  56                 set_bit(index, &line6pcm->in.active_urbs);
  57         else
  58                 dev_err(line6pcm->line6->ifcdev,
  59                         "URB in #%d submission failed (%d)\n", index, ret);
  60
  61         return 0;
  62 }
  63
  64 /*
  65         Submit all currently available capture URBs.
  66         must be called in line6pcm->in.lock context
  67 */
  68 int line6_submit_audio_in_all_urbs(struct snd_line6_pcm *line6pcm)
  69 {
  70         int ret = 0, i;
  71
  72         for (i = 0; i < line6pcm->line6->iso_buffers; ++i) {
  73                 ret = submit_audio_in_urb(line6pcm);
  74                 if (ret < 0)
  75                         break;
  76         }
  77
  78         return ret;
  79 }
  80
  81 /*
  82         Copy data into ALSA capture buffer.
  83 */
  84 void line6_capture_copy(struct snd_line6_pcm *line6pcm, char *fbuf, int fsize)
  85 {
  86         struct snd_pcm_substream *substream =
  87             get_substream(line6pcm, SNDRV_PCM_STREAM_CAPTURE);
  88         struct snd_pcm_runtime *runtime = substream->runtime;
  89         const int bytes_per_frame =
  90                 line6pcm->properties->bytes_per_channel *
  91                 line6pcm->properties->capture_hw.channels_max;
  92         int frames = fsize / bytes_per_frame;
  93
  94         if (runtime == NULL)
  95                 return;
  96
  97         if (line6pcm->in.pos_done + frames > runtime->buffer_size) {
  98                 /*
  99                    The transferred area goes over buffer boundary,
 100                    copy two separate chunks.
 101                  */
 102                 int len;
 103
 104                 len = runtime->buffer_size - line6pcm->in.pos_done;
 105
 106                 if (len > 0) {
 107                         memcpy(runtime->dma_area +
 108                                line6pcm->in.pos_done * bytes_per_frame, fbuf,
 109                                len * bytes_per_frame);
 110                         memcpy(runtime->dma_area, fbuf + len * bytes_per_frame,
 111                                (frames - len) * bytes_per_frame);
 112                 } else {
 113                         /* this is somewhat paranoid */
 114                         dev_err(line6pcm->line6->ifcdev,
 115                                 "driver bug: len = %d\n", len);
 116                 }
 117         } else {
 118                 /* copy single chunk */
 119                 memcpy(runtime->dma_area +
 120                        line6pcm->in.pos_done * bytes_per_frame, fbuf, fsize);
 121         }
 122
 123         line6pcm->in.pos_done += frames;
 124         if (line6pcm->in.pos_done >= runtime->buffer_size)
 125                 line6pcm->in.pos_done -= runtime->buffer_size;
 126 }
 127
 128 void line6_capture_check_period(struct snd_line6_pcm *line6pcm, int length)
 129 {
 130         struct snd_pcm_substream *substream =
 131             get_substream(line6pcm, SNDRV_PCM_STREAM_CAPTURE);
 132
 133         line6pcm->in.bytes += length;
 134         if (line6pcm->in.bytes >= line6pcm->in.period) {
 135                 line6pcm->in.bytes %= line6pcm->in.period;
 136                 spin_unlock(&line6pcm->in.lock);
 137                 snd_pcm_period_elapsed(substream);
 138                 spin_lock(&line6pcm->in.lock);
 139         }
 140 }
 141
 142 /*
 143  * Callback for completed capture URB.
 144  */
 145 static void audio_in_callback(struct urb *urb)
 146 {
 147         int i, index, length = 0, shutdown = 0;
 148         unsigned long flags;
 149
 150         struct snd_line6_pcm *line6pcm = (struct snd_line6_pcm *)urb->context;
 151
 152         line6pcm->in.last_frame = urb->start_frame;
 153
 154         /* find index of URB */
 155         for (index = 0; index < line6pcm->line6->iso_buffers; ++index)
 156                 if (urb == line6pcm->in.urbs[index])
 157                         break;
 158
 159         spin_lock_irqsave(&line6pcm->in.lock, flags);
 160
 161         for (i = 0; i < LINE6_ISO_PACKETS; ++i) {
 162                 char *fbuf;
 163                 int fsize;
 164                 struct usb_iso_packet_descriptor *fin = &urb->iso_frame_desc[i];
 165
 166                 if (fin->status == -EXDEV) {
 167                         shutdown = 1;
 168                         break;
 169                 }
 170
 171                 fbuf = urb->transfer_buffer + fin->offset;
 172                 fsize = fin->actual_length;
 173
 174                 if (fsize > line6pcm->max_packet_size_in) {
 175                         dev_err(line6pcm->line6->ifcdev,
 176                                 "driver and/or device bug: packet too large (%d > %d)\n",
 177                                 fsize, line6pcm->max_packet_size_in);
 178                 }
 179
 180                 length += fsize;
 181
 182                 BUILD_BUG_ON_MSG(LINE6_ISO_PACKETS != 1,
 183                         "The following code assumes LINE6_ISO_PACKETS == 1");
 184                 /* TODO:
 185                  * Also, if iso_buffers != 2, the prev frame is almost random at
 186                  * playback side.
 187                  * This needs to be redesigned. It should be "stable", but we may
 188                  * experience sync problems on such high-speed configs.
 189                  */
 190
 191                 line6pcm->prev_fbuf = fbuf;
 192                 line6pcm->prev_fsize = fsize /
 193                         (line6pcm->properties->bytes_per_channel *
 194                         line6pcm->properties->capture_hw.channels_max);
 195
 196                 if (!test_bit(LINE6_STREAM_IMPULSE, &line6pcm->in.running) &&
 197                     test_bit(LINE6_STREAM_PCM, &line6pcm->in.running) &&
 198                     fsize > 0)
 199                         line6_capture_copy(line6pcm, fbuf, fsize);
 200         }
 201
 202         clear_bit(index, &line6pcm->in.active_urbs);
 203
 204         if (test_and_clear_bit(index, &line6pcm->in.unlink_urbs))
 205                 shutdown = 1;
 206
 207         if (!shutdown) {
 208                 submit_audio_in_urb(line6pcm);
 209
 210                 if (!test_bit(LINE6_STREAM_IMPULSE, &line6pcm->in.running) &&
 211                     test_bit(LINE6_STREAM_PCM, &line6pcm->in.running))
 212                         line6_capture_check_period(line6pcm, length);
 213         }
 214
 215         spin_unlock_irqrestore(&line6pcm->in.lock, flags);
 216 }
 217
 218 /* open capture callback */
 219 static int snd_line6_capture_open(struct snd_pcm_substream *substream)
 220 {
 221         int err;
 222         struct snd_pcm_runtime *runtime = substream->runtime;
 223         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
 224
 225         err = snd_pcm_hw_constraint_ratdens(runtime, 0,
 226                                             SNDRV_PCM_HW_PARAM_RATE,
 227                                             &line6pcm->properties->rates);
 228         if (err < 0)
 229                 return err;
 230
 231         line6_pcm_acquire(line6pcm, LINE6_STREAM_CAPTURE_HELPER, false);
 232
 233         runtime->hw = line6pcm->properties->capture_hw;
 234         return 0;
 235 }
 236
 237 /* close capture callback */
 238 static int snd_line6_capture_close(struct snd_pcm_substream *substream)
 239 {
 240         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
 241
 242         line6_pcm_release(line6pcm, LINE6_STREAM_CAPTURE_HELPER);
 243         return 0;
 244 }
 245
 246 /* capture operators */
 247 const struct snd_pcm_ops snd_line6_capture_ops = {
 248         .open = snd_line6_capture_open,
 249         .close = snd_line6_capture_close,
 250         .hw_params = snd_line6_hw_params,
 251         .hw_free = snd_line6_hw_free,
 252         .prepare = snd_line6_prepare,
 253         .trigger = snd_line6_trigger,
 254         .pointer = snd_line6_pointer,
 255 };
 256
 257 int line6_create_audio_in_urbs(struct snd_line6_pcm *line6pcm)
 258 {
 259         struct usb_line6 *line6 = line6pcm->line6;
 260         int i;
 261
 262         line6pcm->in.urbs = kcalloc(line6->iso_buffers, sizeof(struct urb *),
 263                                     GFP_KERNEL);
 264         if (line6pcm->in.urbs == NULL)
 265                 return -ENOMEM;
 266
 267         /* create audio URBs and fill in constant values: */
 268         for (i = 0; i < line6->iso_buffers; ++i) {
 269                 struct urb *urb;
 270
 271                 /* URB for audio in: */
 272                 urb = line6pcm->in.urbs[i] =
 273                     usb_alloc_urb(LINE6_ISO_PACKETS, GFP_KERNEL);
 274
 275                 if (urb == NULL)
 276                         return -ENOMEM;
 277
 278                 urb->dev = line6->usbdev;
 279                 urb->pipe =
 280                     usb_rcvisocpipe(line6->usbdev,
 281                                     line6->properties->ep_audio_r &
 282                                     USB_ENDPOINT_NUMBER_MASK);
 283                 urb->transfer_flags = URB_ISO_ASAP;
 284                 urb->start_frame = -1;
 285                 urb->number_of_packets = LINE6_ISO_PACKETS;
 286                 urb->interval = LINE6_ISO_INTERVAL;
 287                 urb->error_count = 0;
 288                 urb->complete = audio_in_callback;
 289                 if (usb_urb_ep_type_check(urb))
 290                         return -EINVAL;
 291         }
 292
 293         return 0;
 294 }