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
21 /*
22 Find a free URB and submit it.
23 must be called in line6pcm->in.lock context
24 */
submit_audio_in_urb(struct snd_line6_pcm * line6pcm)25 static int submit_audio_in_urb(struct snd_line6_pcm *line6pcm)
26 {
27 int index;
28 int i, urb_size;
29 int ret;
30 struct urb *urb_in;
31
32 index = find_first_zero_bit(&line6pcm->in.active_urbs,
33 line6pcm->line6->iso_buffers);
34
35 if (index < 0 || index >= line6pcm->line6->iso_buffers) {
36 dev_err(line6pcm->line6->ifcdev, "no free URB found\n");
37 return -EINVAL;
38 }
39
40 urb_in = line6pcm->in.urbs[index];
41 urb_size = 0;
42
43 for (i = 0; i < LINE6_ISO_PACKETS; ++i) {
44 struct usb_iso_packet_descriptor *fin =
45 &urb_in->iso_frame_desc[i];
46 fin->offset = urb_size;
47 fin->length = line6pcm->max_packet_size_in;
48 urb_size += line6pcm->max_packet_size_in;
49 }
50
51 urb_in->transfer_buffer =
52 line6pcm->in.buffer +
53 index * LINE6_ISO_PACKETS * line6pcm->max_packet_size_in;
54 urb_in->transfer_buffer_length = urb_size;
55 urb_in->context = line6pcm;
56
57 ret = usb_submit_urb(urb_in, GFP_ATOMIC);
58
59 if (ret == 0)
60 set_bit(index, &line6pcm->in.active_urbs);
61 else
62 dev_err(line6pcm->line6->ifcdev,
63 "URB in #%d submission failed (%d)\n", index, ret);
64
65 return 0;
66 }
67
68 /*
69 Submit all currently available capture URBs.
70 must be called in line6pcm->in.lock context
71 */
line6_submit_audio_in_all_urbs(struct snd_line6_pcm * line6pcm)72 int line6_submit_audio_in_all_urbs(struct snd_line6_pcm *line6pcm)
73 {
74 int ret = 0, i;
75
76 for (i = 0; i < line6pcm->line6->iso_buffers; ++i) {
77 ret = submit_audio_in_urb(line6pcm);
78 if (ret < 0)
79 break;
80 }
81
82 return ret;
83 }
84
85 /*
86 Copy data into ALSA capture buffer.
87 */
line6_capture_copy(struct snd_line6_pcm * line6pcm,char * fbuf,int fsize)88 void line6_capture_copy(struct snd_line6_pcm *line6pcm, char *fbuf, int fsize)
89 {
90 struct snd_pcm_substream *substream =
91 get_substream(line6pcm, SNDRV_PCM_STREAM_CAPTURE);
92 struct snd_pcm_runtime *runtime = substream->runtime;
93 const int bytes_per_frame =
94 line6pcm->properties->bytes_per_channel *
95 line6pcm->properties->capture_hw.channels_max;
96 int frames = fsize / bytes_per_frame;
97
98 if (runtime == NULL)
99 return;
100
101 if (line6pcm->in.pos_done + frames > runtime->buffer_size) {
102 /*
103 The transferred area goes over buffer boundary,
104 copy two separate chunks.
105 */
106 int len;
107
108 len = runtime->buffer_size - line6pcm->in.pos_done;
109
110 if (len > 0) {
111 memcpy(runtime->dma_area +
112 line6pcm->in.pos_done * bytes_per_frame, fbuf,
113 len * bytes_per_frame);
114 memcpy(runtime->dma_area, fbuf + len * bytes_per_frame,
115 (frames - len) * bytes_per_frame);
116 } else {
117 /* this is somewhat paranoid */
118 dev_err(line6pcm->line6->ifcdev,
119 "driver bug: len = %d\n", len);
120 }
121 } else {
122 /* copy single chunk */
123 memcpy(runtime->dma_area +
124 line6pcm->in.pos_done * bytes_per_frame, fbuf, fsize);
125 }
126
127 line6pcm->in.pos_done += frames;
128 if (line6pcm->in.pos_done >= runtime->buffer_size)
129 line6pcm->in.pos_done -= runtime->buffer_size;
130 }
131
line6_capture_check_period(struct snd_line6_pcm * line6pcm,int length)132 void line6_capture_check_period(struct snd_line6_pcm *line6pcm, int length)
133 {
134 struct snd_pcm_substream *substream =
135 get_substream(line6pcm, SNDRV_PCM_STREAM_CAPTURE);
136
137 line6pcm->in.bytes += length;
138 if (line6pcm->in.bytes >= line6pcm->in.period) {
139 line6pcm->in.bytes %= line6pcm->in.period;
140 spin_unlock(&line6pcm->in.lock);
141 snd_pcm_period_elapsed(substream);
142 spin_lock(&line6pcm->in.lock);
143 }
144 }
145
146 /*
147 * Callback for completed capture URB.
148 */
audio_in_callback(struct urb * urb)149 static void audio_in_callback(struct urb *urb)
150 {
151 int i, index, length = 0, shutdown = 0;
152 unsigned long flags;
153
154 struct snd_line6_pcm *line6pcm = (struct snd_line6_pcm *)urb->context;
155
156 line6pcm->in.last_frame = urb->start_frame;
157
158 /* find index of URB */
159 for (index = 0; index < line6pcm->line6->iso_buffers; ++index)
160 if (urb == line6pcm->in.urbs[index])
161 break;
162
163 spin_lock_irqsave(&line6pcm->in.lock, flags);
164
165 for (i = 0; i < LINE6_ISO_PACKETS; ++i) {
166 char *fbuf;
167 int fsize;
168 struct usb_iso_packet_descriptor *fin = &urb->iso_frame_desc[i];
169
170 if (fin->status == -EXDEV) {
171 shutdown = 1;
172 break;
173 }
174
175 fbuf = urb->transfer_buffer + fin->offset;
176 fsize = fin->actual_length;
177
178 if (fsize > line6pcm->max_packet_size_in) {
179 dev_err(line6pcm->line6->ifcdev,
180 "driver and/or device bug: packet too large (%d > %d)\n",
181 fsize, line6pcm->max_packet_size_in);
182 }
183
184 length += fsize;
185
186 BUILD_BUG_ON_MSG(LINE6_ISO_PACKETS != 1,
187 "The following code assumes LINE6_ISO_PACKETS == 1");
188 /* TODO:
189 * Also, if iso_buffers != 2, the prev frame is almost random at
190 * playback side.
191 * This needs to be redesigned. It should be "stable", but we may
192 * experience sync problems on such high-speed configs.
193 */
194
195 line6pcm->prev_fbuf = fbuf;
196 line6pcm->prev_fsize = fsize /
197 (line6pcm->properties->bytes_per_channel *
198 line6pcm->properties->capture_hw.channels_max);
199
200 if (!test_bit(LINE6_STREAM_IMPULSE, &line6pcm->in.running) &&
201 test_bit(LINE6_STREAM_PCM, &line6pcm->in.running) &&
202 fsize > 0)
203 line6_capture_copy(line6pcm, fbuf, fsize);
204 }
205
206 clear_bit(index, &line6pcm->in.active_urbs);
207
208 if (test_and_clear_bit(index, &line6pcm->in.unlink_urbs))
209 shutdown = 1;
210
211 if (!shutdown) {
212 submit_audio_in_urb(line6pcm);
213
214 if (!test_bit(LINE6_STREAM_IMPULSE, &line6pcm->in.running) &&
215 test_bit(LINE6_STREAM_PCM, &line6pcm->in.running))
216 line6_capture_check_period(line6pcm, length);
217 }
218
219 spin_unlock_irqrestore(&line6pcm->in.lock, flags);
220 }
221
222 /* open capture callback */
snd_line6_capture_open(struct snd_pcm_substream * substream)223 static int snd_line6_capture_open(struct snd_pcm_substream *substream)
224 {
225 int err;
226 struct snd_pcm_runtime *runtime = substream->runtime;
227 struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
228
229 err = snd_pcm_hw_constraint_ratdens(runtime, 0,
230 SNDRV_PCM_HW_PARAM_RATE,
231 &line6pcm->properties->rates);
232 if (err < 0)
233 return err;
234
235 line6_pcm_acquire(line6pcm, LINE6_STREAM_CAPTURE_HELPER, false);
236
237 runtime->hw = line6pcm->properties->capture_hw;
238 return 0;
239 }
240
241 /* close capture callback */
snd_line6_capture_close(struct snd_pcm_substream * substream)242 static int snd_line6_capture_close(struct snd_pcm_substream *substream)
243 {
244 struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
245
246 line6_pcm_release(line6pcm, LINE6_STREAM_CAPTURE_HELPER);
247 return 0;
248 }
249
250 /* capture operators */
251 struct snd_pcm_ops snd_line6_capture_ops = {
252 .open = snd_line6_capture_open,
253 .close = snd_line6_capture_close,
254 .ioctl = snd_pcm_lib_ioctl,
255 .hw_params = snd_line6_hw_params,
256 .hw_free = snd_line6_hw_free,
257 .prepare = snd_line6_prepare,
258 .trigger = snd_line6_trigger,
259 .pointer = snd_line6_pointer,
260 };
261
line6_create_audio_in_urbs(struct snd_line6_pcm * line6pcm)262 int line6_create_audio_in_urbs(struct snd_line6_pcm *line6pcm)
263 {
264 struct usb_line6 *line6 = line6pcm->line6;
265 int i;
266
267 line6pcm->in.urbs = kzalloc(
268 sizeof(struct urb *) * line6->iso_buffers, GFP_KERNEL);
269 if (line6pcm->in.urbs == NULL)
270 return -ENOMEM;
271
272 /* create audio URBs and fill in constant values: */
273 for (i = 0; i < line6->iso_buffers; ++i) {
274 struct urb *urb;
275
276 /* URB for audio in: */
277 urb = line6pcm->in.urbs[i] =
278 usb_alloc_urb(LINE6_ISO_PACKETS, GFP_KERNEL);
279
280 if (urb == NULL)
281 return -ENOMEM;
282
283 urb->dev = line6->usbdev;
284 urb->pipe =
285 usb_rcvisocpipe(line6->usbdev,
286 line6->properties->ep_audio_r &
287 USB_ENDPOINT_NUMBER_MASK);
288 urb->transfer_flags = URB_ISO_ASAP;
289 urb->start_frame = -1;
290 urb->number_of_packets = LINE6_ISO_PACKETS;
291 urb->interval = LINE6_ISO_INTERVAL;
292 urb->error_count = 0;
293 urb->complete = audio_in_callback;
294 }
295
296 return 0;
297 }
298