2 * Line 6 Linux USB driver
4 * Copyright (C) 2004-2010 Markus Grabner (grabner@icg.tugraz.at)
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.
12 #include <linux/slab.h>
13 #include <sound/core.h>
14 #include <sound/pcm.h>
15 #include <sound/pcm_params.h>
23 Software stereo volume control.
25 static void change_volume(struct urb
*urb_out
, int volume
[],
30 if (volume
[0] == 256 && volume
[1] == 256)
31 return; /* maximum volume - no change */
33 if (bytes_per_frame
== 4) {
36 p
= (__le16
*)urb_out
->transfer_buffer
;
37 buf_end
= p
+ urb_out
->transfer_buffer_length
/ sizeof(*p
);
39 for (; p
< buf_end
; ++p
) {
40 short pv
= le16_to_cpu(*p
);
41 int val
= (pv
* volume
[chn
& 1]) >> 8;
42 pv
= clamp(val
, -0x8000, 0x7fff);
46 } else if (bytes_per_frame
== 6) {
47 unsigned char *p
, *buf_end
;
49 p
= (unsigned char *)urb_out
->transfer_buffer
;
50 buf_end
= p
+ urb_out
->transfer_buffer_length
;
52 for (; p
< buf_end
; p
+= 3) {
55 val
= p
[0] + (p
[1] << 8) + ((signed char)p
[2] << 16);
56 val
= (val
* volume
[chn
& 1]) >> 8;
57 val
= clamp(val
, -0x800000, 0x7fffff);
67 Create signal for impulse response test.
69 static void create_impulse_test_signal(struct snd_line6_pcm
*line6pcm
,
70 struct urb
*urb_out
, int bytes_per_frame
)
72 int frames
= urb_out
->transfer_buffer_length
/ bytes_per_frame
;
74 if (bytes_per_frame
== 4) {
76 short *pi
= (short *)line6pcm
->prev_fbuf
;
77 short *po
= (short *)urb_out
->transfer_buffer
;
79 for (i
= 0; i
< frames
; ++i
) {
85 } else if (bytes_per_frame
== 6) {
87 unsigned char *pi
= line6pcm
->prev_fbuf
;
88 unsigned char *po
= urb_out
->transfer_buffer
;
90 for (i
= 0; i
< frames
; ++i
) {
91 for (j
= 0; j
< bytes_per_frame
/ 2; ++j
)
94 for (; j
< bytes_per_frame
; ++j
)
97 pi
+= bytes_per_frame
;
98 po
+= bytes_per_frame
;
101 if (--line6pcm
->impulse_count
<= 0) {
102 ((unsigned char *)(urb_out
->transfer_buffer
))[bytes_per_frame
-
104 line6pcm
->impulse_volume
;
105 line6pcm
->impulse_count
= line6pcm
->impulse_period
;
110 Add signal to buffer for software monitoring.
112 static void add_monitor_signal(struct urb
*urb_out
, unsigned char *signal
,
113 int volume
, int bytes_per_frame
)
116 return; /* zero volume - no change */
118 if (bytes_per_frame
== 4) {
119 __le16
*pi
, *po
, *buf_end
;
121 pi
= (__le16
*)signal
;
122 po
= (__le16
*)urb_out
->transfer_buffer
;
123 buf_end
= po
+ urb_out
->transfer_buffer_length
/ sizeof(*po
);
125 for (; po
< buf_end
; ++pi
, ++po
) {
126 short pov
= le16_to_cpu(*po
);
127 short piv
= le16_to_cpu(*pi
);
128 int val
= pov
+ ((piv
* volume
) >> 8);
129 pov
= clamp(val
, -0x8000, 0x7fff);
130 *po
= cpu_to_le16(pov
);
135 We don't need to handle devices with 6 bytes per frame here
136 since they all support hardware monitoring.
141 Find a free URB, prepare audio data, and submit URB.
142 must be called in line6pcm->out.lock context
144 static int submit_audio_out_urb(struct snd_line6_pcm
*line6pcm
)
147 int i
, urb_size
, urb_frames
;
149 const int bytes_per_frame
= line6pcm
->properties
->bytes_per_frame
;
150 const int frame_increment
=
151 line6pcm
->properties
->rates
.rats
[0].num_min
;
152 const int frame_factor
=
153 line6pcm
->properties
->rates
.rats
[0].den
*
154 (USB_INTERVALS_PER_SECOND
/ LINE6_ISO_INTERVAL
);
158 find_first_zero_bit(&line6pcm
->out
.active_urbs
, LINE6_ISO_BUFFERS
);
160 if (index
< 0 || index
>= LINE6_ISO_BUFFERS
) {
161 dev_err(line6pcm
->line6
->ifcdev
, "no free URB found\n");
165 urb_out
= line6pcm
->out
.urbs
[index
];
168 for (i
= 0; i
< LINE6_ISO_PACKETS
; ++i
) {
169 /* compute frame size for given sampling rate */
171 struct usb_iso_packet_descriptor
*fout
=
172 &urb_out
->iso_frame_desc
[i
];
174 fsize
= line6pcm
->prev_fsize
;
178 line6pcm
->out
.count
+= frame_increment
;
179 n
= line6pcm
->out
.count
/ frame_factor
;
180 line6pcm
->out
.count
-= n
* frame_factor
;
181 fsize
= n
* bytes_per_frame
;
184 fout
->offset
= urb_size
;
185 fout
->length
= fsize
;
190 /* can't determine URB size */
191 dev_err(line6pcm
->line6
->ifcdev
, "driver bug: urb_size = 0\n");
195 urb_frames
= urb_size
/ bytes_per_frame
;
196 urb_out
->transfer_buffer
=
197 line6pcm
->out
.buffer
+
198 index
* LINE6_ISO_PACKETS
* line6pcm
->max_packet_size
;
199 urb_out
->transfer_buffer_length
= urb_size
;
200 urb_out
->context
= line6pcm
;
202 if (test_bit(LINE6_STREAM_PCM
, &line6pcm
->out
.running
) &&
203 !test_bit(LINE6_FLAG_PAUSE_PLAYBACK
, &line6pcm
->flags
)) {
204 struct snd_pcm_runtime
*runtime
=
205 get_substream(line6pcm
, SNDRV_PCM_STREAM_PLAYBACK
)->runtime
;
207 if (line6pcm
->out
.pos
+ urb_frames
> runtime
->buffer_size
) {
209 The transferred area goes over buffer boundary,
210 copy the data to the temp buffer.
214 len
= runtime
->buffer_size
- line6pcm
->out
.pos
;
217 memcpy(urb_out
->transfer_buffer
,
219 line6pcm
->out
.pos
* bytes_per_frame
,
220 len
* bytes_per_frame
);
221 memcpy(urb_out
->transfer_buffer
+
222 len
* bytes_per_frame
, runtime
->dma_area
,
223 (urb_frames
- len
) * bytes_per_frame
);
225 dev_err(line6pcm
->line6
->ifcdev
, "driver bug: len = %d\n",
228 memcpy(urb_out
->transfer_buffer
,
230 line6pcm
->out
.pos
* bytes_per_frame
,
231 urb_out
->transfer_buffer_length
);
234 line6pcm
->out
.pos
+= urb_frames
;
235 if (line6pcm
->out
.pos
>= runtime
->buffer_size
)
236 line6pcm
->out
.pos
-= runtime
->buffer_size
;
238 change_volume(urb_out
, line6pcm
->volume_playback
,
241 memset(urb_out
->transfer_buffer
, 0,
242 urb_out
->transfer_buffer_length
);
245 spin_lock_nested(&line6pcm
->in
.lock
, SINGLE_DEPTH_NESTING
);
246 if (line6pcm
->prev_fbuf
) {
247 if (test_bit(LINE6_STREAM_IMPULSE
, &line6pcm
->out
.running
)) {
248 create_impulse_test_signal(line6pcm
, urb_out
,
250 if (test_bit(LINE6_STREAM_PCM
, &line6pcm
->in
.running
)) {
251 line6_capture_copy(line6pcm
,
252 urb_out
->transfer_buffer
,
254 transfer_buffer_length
);
255 line6_capture_check_period(line6pcm
,
256 urb_out
->transfer_buffer_length
);
259 if (!(line6pcm
->line6
->properties
->capabilities
& LINE6_CAP_HWMON
)
260 && line6pcm
->out
.running
&& line6pcm
->in
.running
)
261 add_monitor_signal(urb_out
, line6pcm
->prev_fbuf
,
262 line6pcm
->volume_monitor
,
265 line6pcm
->prev_fbuf
= NULL
;
266 line6pcm
->prev_fsize
= 0;
268 spin_unlock(&line6pcm
->in
.lock
);
270 ret
= usb_submit_urb(urb_out
, GFP_ATOMIC
);
273 set_bit(index
, &line6pcm
->out
.active_urbs
);
275 dev_err(line6pcm
->line6
->ifcdev
,
276 "URB out #%d submission failed (%d)\n", index
, ret
);
282 Submit all currently available playback URBs.
283 must be called in line6pcm->out.lock context
285 int line6_submit_audio_out_all_urbs(struct snd_line6_pcm
*line6pcm
)
289 for (i
= 0; i
< LINE6_ISO_BUFFERS
; ++i
) {
290 ret
= submit_audio_out_urb(line6pcm
);
299 Callback for completed playback URB.
301 static void audio_out_callback(struct urb
*urb
)
303 int i
, index
, length
= 0, shutdown
= 0;
305 struct snd_line6_pcm
*line6pcm
= (struct snd_line6_pcm
*)urb
->context
;
306 struct snd_pcm_substream
*substream
=
307 get_substream(line6pcm
, SNDRV_PCM_STREAM_PLAYBACK
);
309 #if USE_CLEAR_BUFFER_WORKAROUND
310 memset(urb
->transfer_buffer
, 0, urb
->transfer_buffer_length
);
313 line6pcm
->out
.last_frame
= urb
->start_frame
;
315 /* find index of URB */
316 for (index
= 0; index
< LINE6_ISO_BUFFERS
; index
++)
317 if (urb
== line6pcm
->out
.urbs
[index
])
320 if (index
>= LINE6_ISO_BUFFERS
)
321 return; /* URB has been unlinked asynchronously */
323 for (i
= 0; i
< LINE6_ISO_PACKETS
; i
++)
324 length
+= urb
->iso_frame_desc
[i
].length
;
326 spin_lock_irqsave(&line6pcm
->out
.lock
, flags
);
328 if (test_bit(LINE6_STREAM_PCM
, &line6pcm
->out
.running
)) {
329 struct snd_pcm_runtime
*runtime
= substream
->runtime
;
331 line6pcm
->out
.pos_done
+=
332 length
/ line6pcm
->properties
->bytes_per_frame
;
334 if (line6pcm
->out
.pos_done
>= runtime
->buffer_size
)
335 line6pcm
->out
.pos_done
-= runtime
->buffer_size
;
338 clear_bit(index
, &line6pcm
->out
.active_urbs
);
340 for (i
= 0; i
< LINE6_ISO_PACKETS
; i
++)
341 if (urb
->iso_frame_desc
[i
].status
== -EXDEV
) {
346 if (test_and_clear_bit(index
, &line6pcm
->out
.unlink_urbs
))
350 submit_audio_out_urb(line6pcm
);
352 if (test_bit(LINE6_STREAM_PCM
, &line6pcm
->out
.running
)) {
353 line6pcm
->out
.bytes
+= length
;
354 if (line6pcm
->out
.bytes
>= line6pcm
->out
.period
) {
355 line6pcm
->out
.bytes
%= line6pcm
->out
.period
;
356 spin_unlock(&line6pcm
->out
.lock
);
357 snd_pcm_period_elapsed(substream
);
358 spin_lock(&line6pcm
->out
.lock
);
362 spin_unlock_irqrestore(&line6pcm
->out
.lock
, flags
);
365 /* open playback callback */
366 static int snd_line6_playback_open(struct snd_pcm_substream
*substream
)
369 struct snd_pcm_runtime
*runtime
= substream
->runtime
;
370 struct snd_line6_pcm
*line6pcm
= snd_pcm_substream_chip(substream
);
372 err
= snd_pcm_hw_constraint_ratdens(runtime
, 0, SNDRV_PCM_HW_PARAM_RATE
,
373 &line6pcm
->properties
->rates
);
377 runtime
->hw
= line6pcm
->properties
->playback_hw
;
381 /* close playback callback */
382 static int snd_line6_playback_close(struct snd_pcm_substream
*substream
)
387 /* playback operators */
388 struct snd_pcm_ops snd_line6_playback_ops
= {
389 .open
= snd_line6_playback_open
,
390 .close
= snd_line6_playback_close
,
391 .ioctl
= snd_pcm_lib_ioctl
,
392 .hw_params
= snd_line6_hw_params
,
393 .hw_free
= snd_line6_hw_free
,
394 .prepare
= snd_line6_prepare
,
395 .trigger
= snd_line6_trigger
,
396 .pointer
= snd_line6_pointer
,
399 int line6_create_audio_out_urbs(struct snd_line6_pcm
*line6pcm
)
401 struct usb_line6
*line6
= line6pcm
->line6
;
404 /* create audio URBs and fill in constant values: */
405 for (i
= 0; i
< LINE6_ISO_BUFFERS
; ++i
) {
408 /* URB for audio out: */
409 urb
= line6pcm
->out
.urbs
[i
] =
410 usb_alloc_urb(LINE6_ISO_PACKETS
, GFP_KERNEL
);
415 urb
->dev
= line6
->usbdev
;
417 usb_sndisocpipe(line6
->usbdev
,
418 line6
->properties
->ep_audio_w
&
419 USB_ENDPOINT_NUMBER_MASK
);
420 urb
->transfer_flags
= URB_ISO_ASAP
;
421 urb
->start_frame
= -1;
422 urb
->number_of_packets
= LINE6_ISO_PACKETS
;
423 urb
->interval
= LINE6_ISO_INTERVAL
;
424 urb
->error_count
= 0;
425 urb
->complete
= audio_out_callback
;