Staging: line6: fix up NULL assignment mistakes
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / staging / line6 / playback.c
blob34cfbdbb15a231f13ac27c2da62de003bd289c79
1 /*
2 * Line6 Linux USB driver - 0.8.0
4 * Copyright (C) 2004-2009 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 "driver.h"
14 #include <sound/core.h>
15 #include <sound/pcm.h>
16 #include <sound/pcm_params.h>
18 #include "audio.h"
19 #include "pcm.h"
20 #include "pod.h"
21 #include "playback.h"
25 Software stereo volume control.
27 static void change_volume(struct urb *urb_out, int volume[], int bytes_per_frame)
29 int chn = 0;
31 if(volume[0] == 256 && volume[1] == 256)
32 return; /* maximum volume - no change */
34 if(bytes_per_frame == 4) {
35 short *p, *buf_end;
36 p = (short *)urb_out->transfer_buffer;
37 buf_end = p + urb_out->transfer_buffer_length / sizeof(*p);
39 for(; p < buf_end; ++p) {
40 *p = (*p * volume[chn & 1]) >> 8;
41 ++chn;
44 else if(bytes_per_frame == 6) {
45 unsigned char *p, *buf_end;
46 p = (unsigned char *)urb_out->transfer_buffer;
47 buf_end = p + urb_out->transfer_buffer_length;
49 for(; p < buf_end; p += 3) {
50 int val = p[0] + (p[1] << 8) + ((signed char)p[2] << 16);
51 val = (val * volume[chn & 1]) >> 8;
52 p[0] = val;
53 p[1] = val >> 8;
54 p[2] = val >> 16;
55 ++chn;
61 Find a free URB, prepare audio data, and submit URB.
63 static int submit_audio_out_urb(struct snd_pcm_substream *substream)
65 int index;
66 unsigned long flags;
67 int i, urb_size, urb_frames;
68 struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
69 const int bytes_per_frame = line6pcm->properties->bytes_per_frame;
70 const int frame_increment = line6pcm->properties->snd_line6_rates.rats[0].num_min;
71 const int frame_factor = line6pcm->properties->snd_line6_rates.rats[0].den * (USB_INTERVALS_PER_SECOND / LINE6_ISO_INTERVAL);
72 struct snd_pcm_runtime *runtime = substream->runtime;
73 struct urb *urb_out;
75 spin_lock_irqsave(&line6pcm->lock_audio_out, flags);
76 index = find_first_zero_bit(&line6pcm->active_urb_out, LINE6_ISO_BUFFERS);
78 if(index < 0 || index >= LINE6_ISO_BUFFERS) {
79 spin_unlock_irqrestore(&line6pcm->lock_audio_out, flags);
80 dev_err(s2m(substream), "no free URB found\n");
81 return -EINVAL;
84 urb_out = line6pcm->urb_audio_out[index];
85 urb_size = 0;
87 for(i = 0; i < LINE6_ISO_PACKETS; ++i) {
88 /* compute frame size for given sampling rate */
89 int n, fs;
90 struct usb_iso_packet_descriptor *fout = &urb_out->iso_frame_desc[i];
91 line6pcm->count_out += frame_increment;
92 n = line6pcm->count_out / frame_factor;
93 line6pcm->count_out -= n * frame_factor;
94 fs = n * bytes_per_frame;
95 fout->offset = urb_size;
96 fout->length = fs;
97 urb_size += fs;
100 urb_frames = urb_size / bytes_per_frame;
102 if(test_bit(BIT_PAUSE_PLAYBACK, &line6pcm->flags)) {
103 urb_out->transfer_buffer = line6pcm->wrap_out;
104 memset(line6pcm->wrap_out, 0, urb_size);
106 else {
107 if(line6pcm->pos_out + urb_frames > runtime->buffer_size) {
109 The transferred area goes over buffer boundary,
110 copy the data to the temp buffer.
112 int len;
113 len = runtime->buffer_size - line6pcm->pos_out;
114 urb_out->transfer_buffer = line6pcm->wrap_out;
116 if(len > 0) {
117 memcpy(line6pcm->wrap_out, runtime->dma_area + line6pcm->pos_out * bytes_per_frame, len * bytes_per_frame);
118 memcpy(line6pcm->wrap_out + len * bytes_per_frame, runtime->dma_area, (urb_frames - len) * bytes_per_frame);
120 else
121 dev_err(s2m(substream), "driver bug: len = %d\n", len); /* this is somewhat paranoid */
123 else {
124 /* set the buffer pointer */
125 urb_out->transfer_buffer = runtime->dma_area + line6pcm->pos_out * bytes_per_frame;
129 if((line6pcm->pos_out += urb_frames) >= runtime->buffer_size)
130 line6pcm->pos_out -= runtime->buffer_size;
132 urb_out->transfer_buffer_length = urb_size;
133 urb_out->context = substream;
134 change_volume(urb_out, line6pcm->volume, bytes_per_frame);
136 #if DO_DUMP_PCM_SEND
137 for(i = 0; i < LINE6_ISO_PACKETS; ++i) {
138 struct usb_iso_packet_descriptor *fout = &urb_out->iso_frame_desc[i];
139 line6_write_hexdump(line6pcm->line6, 'P', urb_out->transfer_buffer + fout->offset, fout->length);
141 #endif
143 if(usb_submit_urb(urb_out, GFP_ATOMIC) == 0)
144 set_bit(index, &line6pcm->active_urb_out);
145 else
146 dev_err(s2m(substream), "URB out #%d submission failed\n", index);
148 spin_unlock_irqrestore(&line6pcm->lock_audio_out, flags);
149 return 0;
153 Submit all currently available playback URBs.
155 static int submit_audio_out_all_urbs(struct snd_pcm_substream *substream)
157 int ret, i;
159 for(i = 0; i < LINE6_ISO_BUFFERS; ++i)
160 if((ret = submit_audio_out_urb(substream)) < 0)
161 return ret;
163 return 0;
167 Unlink all currently active playback URBs.
169 static void unlink_audio_out_urbs(struct snd_line6_pcm *line6pcm)
171 unsigned int i;
173 for(i = LINE6_ISO_BUFFERS; i--;) {
174 if(test_bit(i, &line6pcm->active_urb_out)) {
175 if(!test_and_set_bit(i, &line6pcm->unlink_urb_out)) {
176 struct urb *u = line6pcm->urb_audio_out[i];
177 usb_unlink_urb(u);
184 Wait until unlinking of all currently active playback URBs has been finished.
186 static void wait_clear_audio_out_urbs(struct snd_line6_pcm *line6pcm)
188 int timeout = HZ;
189 unsigned int i;
190 int alive;
192 do {
193 alive = 0;
194 for (i = LINE6_ISO_BUFFERS; i--;) {
195 if (test_bit(i, &line6pcm->active_urb_out))
196 alive++;
198 if (! alive)
199 break;
200 set_current_state(TASK_UNINTERRUPTIBLE);
201 schedule_timeout(1);
202 } while (--timeout > 0);
203 if (alive)
204 snd_printk(KERN_ERR "timeout: still %d active urbs..\n", alive);
206 line6pcm->active_urb_out = 0;
207 line6pcm->unlink_urb_out = 0;
211 Unlink all currently active playback URBs, and wait for finishing.
213 void unlink_wait_clear_audio_out_urbs(struct snd_line6_pcm *line6pcm)
215 unlink_audio_out_urbs(line6pcm);
216 wait_clear_audio_out_urbs(line6pcm);
220 Callback for completed playback URB.
222 static void audio_out_callback(struct urb *urb)
224 int i, index, length = 0, shutdown = 0;
225 unsigned long flags;
227 struct snd_pcm_substream *substream = (struct snd_pcm_substream *)urb->context;
228 struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
229 struct snd_pcm_runtime *runtime = substream->runtime;
231 /* find index of URB */
232 for(index = LINE6_ISO_BUFFERS; index--;)
233 if(urb == line6pcm->urb_audio_out[index])
234 break;
236 if(index < 0)
237 return; /* URB has been unlinked asynchronously */
239 for(i = LINE6_ISO_PACKETS; i--;)
240 length += urb->iso_frame_desc[i].length;
242 spin_lock_irqsave(&line6pcm->lock_audio_out, flags);
243 line6pcm->pos_out_done += length / line6pcm->properties->bytes_per_frame;
245 if(line6pcm->pos_out_done >= runtime->buffer_size)
246 line6pcm->pos_out_done -= runtime->buffer_size;
248 clear_bit(index, &line6pcm->active_urb_out);
250 for(i = LINE6_ISO_PACKETS; i--;)
251 if(urb->iso_frame_desc[i].status == -ESHUTDOWN) {
252 shutdown = 1;
253 break;
256 if(test_bit(index, &line6pcm->unlink_urb_out))
257 shutdown = 1;
259 spin_unlock_irqrestore(&line6pcm->lock_audio_out, flags);
261 if(!shutdown) {
262 submit_audio_out_urb(substream);
264 if((line6pcm->bytes_out += length) >= line6pcm->period_out) {
265 line6pcm->bytes_out -= line6pcm->period_out;
266 snd_pcm_period_elapsed(substream);
271 /* open playback callback */
272 static int snd_line6_playback_open(struct snd_pcm_substream *substream)
274 int err;
275 struct snd_pcm_runtime *runtime = substream->runtime;
276 struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
278 if((err = snd_pcm_hw_constraint_ratdens(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
279 (&line6pcm->properties->snd_line6_rates))) < 0)
280 return err;
282 runtime->hw = line6pcm->properties->snd_line6_playback_hw;
283 return 0;
286 /* close playback callback */
287 static int snd_line6_playback_close(struct snd_pcm_substream *substream)
289 return 0;
292 /* hw_params playback callback */
293 static int snd_line6_playback_hw_params(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *hw_params)
295 int ret;
296 struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
298 /* -- Florian Demski [FD] */
299 /* don't ask me why, but this fixes the bug on my machine */
300 if ( line6pcm == NULL ) {
301 if ( substream->pcm == NULL )
302 return -ENOMEM;
303 if ( substream->pcm->private_data == NULL )
304 return -ENOMEM;
305 substream->private_data = substream->pcm->private_data;
306 line6pcm = snd_pcm_substream_chip( substream );
308 /* -- [FD] end */
310 if((ret = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(hw_params))) < 0)
311 return ret;
313 line6pcm->period_out = params_period_bytes(hw_params);
314 line6pcm->wrap_out = kmalloc(2 * LINE6_ISO_PACKET_SIZE_MAX, GFP_KERNEL);
316 if(!line6pcm->wrap_out) {
317 dev_err(s2m(substream), "cannot malloc wrap_out\n");
318 return -ENOMEM;
321 return 0;
324 /* hw_free playback callback */
325 static int snd_line6_playback_hw_free(struct snd_pcm_substream *substream)
327 struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
328 unlink_wait_clear_audio_out_urbs(line6pcm);
330 if(line6pcm->wrap_out) {
331 kfree(line6pcm->wrap_out);
332 line6pcm->wrap_out = NULL;
335 return snd_pcm_lib_free_pages(substream);
338 /* trigger playback callback */
339 int snd_line6_playback_trigger(struct snd_pcm_substream *substream, int cmd)
341 struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
342 int err;
343 line6pcm->count_out = 0;
345 switch(cmd) {
346 case SNDRV_PCM_TRIGGER_START:
347 if(!test_and_set_bit(BIT_RUNNING_PLAYBACK, &line6pcm->flags)) {
348 err = submit_audio_out_all_urbs(substream);
350 if(err < 0) {
351 clear_bit(BIT_RUNNING_PLAYBACK, &line6pcm->flags);
352 return err;
356 break;
358 case SNDRV_PCM_TRIGGER_STOP:
359 if(test_and_clear_bit(BIT_RUNNING_PLAYBACK, &line6pcm->flags))
360 unlink_audio_out_urbs(line6pcm);
362 break;
364 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
365 set_bit(BIT_PAUSE_PLAYBACK, &line6pcm->flags);
366 break;
368 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
369 clear_bit(BIT_PAUSE_PLAYBACK, &line6pcm->flags);
370 break;
372 default:
373 return -EINVAL;
376 return 0;
379 /* playback pointer callback */
380 static snd_pcm_uframes_t
381 snd_line6_playback_pointer(struct snd_pcm_substream *substream)
383 struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
384 return line6pcm->pos_out_done;
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_playback_hw_params,
393 .hw_free = snd_line6_playback_hw_free,
394 .prepare = snd_line6_prepare,
395 .trigger = snd_line6_trigger,
396 .pointer = snd_line6_playback_pointer,
399 int create_audio_out_urbs(struct snd_line6_pcm *line6pcm)
401 int i;
403 /* create audio URBs and fill in constant values: */
404 for(i = 0; i < LINE6_ISO_BUFFERS; ++i) {
405 struct urb *urb;
407 /* URB for audio out: */
408 urb = line6pcm->urb_audio_out[i] = usb_alloc_urb(LINE6_ISO_PACKETS, GFP_KERNEL);
410 if(urb == NULL) {
411 dev_err(line6pcm->line6->ifcdev, "Out of memory\n");
412 return -ENOMEM;
415 urb->dev = line6pcm->line6->usbdev;
416 urb->pipe = usb_sndisocpipe(line6pcm->line6->usbdev, line6pcm->ep_audio_write & USB_ENDPOINT_NUMBER_MASK);
417 urb->transfer_flags = URB_ISO_ASAP;
418 urb->start_frame = -1;
419 urb->number_of_packets = LINE6_ISO_PACKETS;
420 urb->interval = LINE6_ISO_INTERVAL;
421 urb->error_count = 0;
422 urb->complete = audio_out_callback;
425 return 0;