Merge tag 'pwm/for-5.2-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git...
[sfrench/cifs-2.6.git] / sound / xen / xen_snd_front_alsa.c
1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2
3 /*
4  * Xen para-virtual sound device
5  *
6  * Copyright (C) 2016-2018 EPAM Systems Inc.
7  *
8  * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
9  */
10
11 #include <linux/platform_device.h>
12
13 #include <sound/core.h>
14 #include <sound/pcm.h>
15 #include <sound/pcm_params.h>
16
17 #include <xen/xenbus.h>
18 #include <xen/xen-front-pgdir-shbuf.h>
19
20 #include "xen_snd_front.h"
21 #include "xen_snd_front_alsa.h"
22 #include "xen_snd_front_cfg.h"
23 #include "xen_snd_front_evtchnl.h"
24
25 struct xen_snd_front_pcm_stream_info {
26         struct xen_snd_front_info *front_info;
27         struct xen_snd_front_evtchnl_pair *evt_pair;
28
29         /* This is the shared buffer with its backing storage. */
30         struct xen_front_pgdir_shbuf shbuf;
31         u8 *buffer;
32         size_t buffer_sz;
33         int num_pages;
34         struct page **pages;
35
36         int index;
37
38         bool is_open;
39         struct snd_pcm_hardware pcm_hw;
40
41         /* Number of processed frames as reported by the backend. */
42         snd_pcm_uframes_t be_cur_frame;
43         /* Current HW pointer to be reported via .period callback. */
44         atomic_t hw_ptr;
45         /* Modulo of the number of processed frames - for period detection. */
46         u32 out_frames;
47 };
48
49 struct xen_snd_front_pcm_instance_info {
50         struct xen_snd_front_card_info *card_info;
51         struct snd_pcm *pcm;
52         struct snd_pcm_hardware pcm_hw;
53         int num_pcm_streams_pb;
54         struct xen_snd_front_pcm_stream_info *streams_pb;
55         int num_pcm_streams_cap;
56         struct xen_snd_front_pcm_stream_info *streams_cap;
57 };
58
59 struct xen_snd_front_card_info {
60         struct xen_snd_front_info *front_info;
61         struct snd_card *card;
62         struct snd_pcm_hardware pcm_hw;
63         int num_pcm_instances;
64         struct xen_snd_front_pcm_instance_info *pcm_instances;
65 };
66
67 struct alsa_sndif_sample_format {
68         u8 sndif;
69         snd_pcm_format_t alsa;
70 };
71
72 struct alsa_sndif_hw_param {
73         u8 sndif;
74         snd_pcm_hw_param_t alsa;
75 };
76
77 static const struct alsa_sndif_sample_format ALSA_SNDIF_FORMATS[] = {
78         {
79                 .sndif = XENSND_PCM_FORMAT_U8,
80                 .alsa = SNDRV_PCM_FORMAT_U8
81         },
82         {
83                 .sndif = XENSND_PCM_FORMAT_S8,
84                 .alsa = SNDRV_PCM_FORMAT_S8
85         },
86         {
87                 .sndif = XENSND_PCM_FORMAT_U16_LE,
88                 .alsa = SNDRV_PCM_FORMAT_U16_LE
89         },
90         {
91                 .sndif = XENSND_PCM_FORMAT_U16_BE,
92                 .alsa = SNDRV_PCM_FORMAT_U16_BE
93         },
94         {
95                 .sndif = XENSND_PCM_FORMAT_S16_LE,
96                 .alsa = SNDRV_PCM_FORMAT_S16_LE
97         },
98         {
99                 .sndif = XENSND_PCM_FORMAT_S16_BE,
100                 .alsa = SNDRV_PCM_FORMAT_S16_BE
101         },
102         {
103                 .sndif = XENSND_PCM_FORMAT_U24_LE,
104                 .alsa = SNDRV_PCM_FORMAT_U24_LE
105         },
106         {
107                 .sndif = XENSND_PCM_FORMAT_U24_BE,
108                 .alsa = SNDRV_PCM_FORMAT_U24_BE
109         },
110         {
111                 .sndif = XENSND_PCM_FORMAT_S24_LE,
112                 .alsa = SNDRV_PCM_FORMAT_S24_LE
113         },
114         {
115                 .sndif = XENSND_PCM_FORMAT_S24_BE,
116                 .alsa = SNDRV_PCM_FORMAT_S24_BE
117         },
118         {
119                 .sndif = XENSND_PCM_FORMAT_U32_LE,
120                 .alsa = SNDRV_PCM_FORMAT_U32_LE
121         },
122         {
123                 .sndif = XENSND_PCM_FORMAT_U32_BE,
124                 .alsa = SNDRV_PCM_FORMAT_U32_BE
125         },
126         {
127                 .sndif = XENSND_PCM_FORMAT_S32_LE,
128                 .alsa = SNDRV_PCM_FORMAT_S32_LE
129         },
130         {
131                 .sndif = XENSND_PCM_FORMAT_S32_BE,
132                 .alsa = SNDRV_PCM_FORMAT_S32_BE
133         },
134         {
135                 .sndif = XENSND_PCM_FORMAT_A_LAW,
136                 .alsa = SNDRV_PCM_FORMAT_A_LAW
137         },
138         {
139                 .sndif = XENSND_PCM_FORMAT_MU_LAW,
140                 .alsa = SNDRV_PCM_FORMAT_MU_LAW
141         },
142         {
143                 .sndif = XENSND_PCM_FORMAT_F32_LE,
144                 .alsa = SNDRV_PCM_FORMAT_FLOAT_LE
145         },
146         {
147                 .sndif = XENSND_PCM_FORMAT_F32_BE,
148                 .alsa = SNDRV_PCM_FORMAT_FLOAT_BE
149         },
150         {
151                 .sndif = XENSND_PCM_FORMAT_F64_LE,
152                 .alsa = SNDRV_PCM_FORMAT_FLOAT64_LE
153         },
154         {
155                 .sndif = XENSND_PCM_FORMAT_F64_BE,
156                 .alsa = SNDRV_PCM_FORMAT_FLOAT64_BE
157         },
158         {
159                 .sndif = XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE,
160                 .alsa = SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE
161         },
162         {
163                 .sndif = XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE,
164                 .alsa = SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE
165         },
166         {
167                 .sndif = XENSND_PCM_FORMAT_IMA_ADPCM,
168                 .alsa = SNDRV_PCM_FORMAT_IMA_ADPCM
169         },
170         {
171                 .sndif = XENSND_PCM_FORMAT_MPEG,
172                 .alsa = SNDRV_PCM_FORMAT_MPEG
173         },
174         {
175                 .sndif = XENSND_PCM_FORMAT_GSM,
176                 .alsa = SNDRV_PCM_FORMAT_GSM
177         },
178 };
179
180 static int to_sndif_format(snd_pcm_format_t format)
181 {
182         int i;
183
184         for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
185                 if (ALSA_SNDIF_FORMATS[i].alsa == format)
186                         return ALSA_SNDIF_FORMATS[i].sndif;
187
188         return -EINVAL;
189 }
190
191 static u64 to_sndif_formats_mask(u64 alsa_formats)
192 {
193         u64 mask;
194         int i;
195
196         mask = 0;
197         for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
198                 if (pcm_format_to_bits(ALSA_SNDIF_FORMATS[i].alsa) & alsa_formats)
199                         mask |= 1 << ALSA_SNDIF_FORMATS[i].sndif;
200
201         return mask;
202 }
203
204 static u64 to_alsa_formats_mask(u64 sndif_formats)
205 {
206         u64 mask;
207         int i;
208
209         mask = 0;
210         for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
211                 if (1 << ALSA_SNDIF_FORMATS[i].sndif & sndif_formats)
212                         mask |= pcm_format_to_bits(ALSA_SNDIF_FORMATS[i].alsa);
213
214         return mask;
215 }
216
217 static void stream_clear(struct xen_snd_front_pcm_stream_info *stream)
218 {
219         stream->is_open = false;
220         stream->be_cur_frame = 0;
221         stream->out_frames = 0;
222         atomic_set(&stream->hw_ptr, 0);
223         xen_snd_front_evtchnl_pair_clear(stream->evt_pair);
224         memset(&stream->shbuf, 0, sizeof(stream->shbuf));
225         stream->buffer = NULL;
226         stream->buffer_sz = 0;
227         stream->pages = NULL;
228         stream->num_pages = 0;
229 }
230
231 static void stream_free(struct xen_snd_front_pcm_stream_info *stream)
232 {
233         xen_front_pgdir_shbuf_unmap(&stream->shbuf);
234         xen_front_pgdir_shbuf_free(&stream->shbuf);
235         if (stream->buffer)
236                 free_pages_exact(stream->buffer, stream->buffer_sz);
237         kfree(stream->pages);
238         stream_clear(stream);
239 }
240
241 static struct xen_snd_front_pcm_stream_info *
242 stream_get(struct snd_pcm_substream *substream)
243 {
244         struct xen_snd_front_pcm_instance_info *pcm_instance =
245                         snd_pcm_substream_chip(substream);
246         struct xen_snd_front_pcm_stream_info *stream;
247
248         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
249                 stream = &pcm_instance->streams_pb[substream->number];
250         else
251                 stream = &pcm_instance->streams_cap[substream->number];
252
253         return stream;
254 }
255
256 static int alsa_hw_rule(struct snd_pcm_hw_params *params,
257                         struct snd_pcm_hw_rule *rule)
258 {
259         struct xen_snd_front_pcm_stream_info *stream = rule->private;
260         struct device *dev = &stream->front_info->xb_dev->dev;
261         struct snd_mask *formats =
262                         hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
263         struct snd_interval *rates =
264                         hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
265         struct snd_interval *channels =
266                         hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
267         struct snd_interval *period =
268                         hw_param_interval(params,
269                                           SNDRV_PCM_HW_PARAM_PERIOD_SIZE);
270         struct snd_interval *buffer =
271                         hw_param_interval(params,
272                                           SNDRV_PCM_HW_PARAM_BUFFER_SIZE);
273         struct xensnd_query_hw_param req;
274         struct xensnd_query_hw_param resp;
275         struct snd_interval interval;
276         struct snd_mask mask;
277         u64 sndif_formats;
278         int changed, ret;
279
280         /* Collect all the values we need for the query. */
281
282         req.formats = to_sndif_formats_mask((u64)formats->bits[0] |
283                                             (u64)(formats->bits[1]) << 32);
284
285         req.rates.min = rates->min;
286         req.rates.max = rates->max;
287
288         req.channels.min = channels->min;
289         req.channels.max = channels->max;
290
291         req.buffer.min = buffer->min;
292         req.buffer.max = buffer->max;
293
294         req.period.min = period->min;
295         req.period.max = period->max;
296
297         ret = xen_snd_front_stream_query_hw_param(&stream->evt_pair->req,
298                                                   &req, &resp);
299         if (ret < 0) {
300                 /* Check if this is due to backend communication error. */
301                 if (ret == -EIO || ret == -ETIMEDOUT)
302                         dev_err(dev, "Failed to query ALSA HW parameters\n");
303                 return ret;
304         }
305
306         /* Refine HW parameters after the query. */
307         changed  = 0;
308
309         sndif_formats = to_alsa_formats_mask(resp.formats);
310         snd_mask_none(&mask);
311         mask.bits[0] = (u32)sndif_formats;
312         mask.bits[1] = (u32)(sndif_formats >> 32);
313         ret = snd_mask_refine(formats, &mask);
314         if (ret < 0)
315                 return ret;
316         changed |= ret;
317
318         interval.openmin = 0;
319         interval.openmax = 0;
320         interval.integer = 1;
321
322         interval.min = resp.rates.min;
323         interval.max = resp.rates.max;
324         ret = snd_interval_refine(rates, &interval);
325         if (ret < 0)
326                 return ret;
327         changed |= ret;
328
329         interval.min = resp.channels.min;
330         interval.max = resp.channels.max;
331         ret = snd_interval_refine(channels, &interval);
332         if (ret < 0)
333                 return ret;
334         changed |= ret;
335
336         interval.min = resp.buffer.min;
337         interval.max = resp.buffer.max;
338         ret = snd_interval_refine(buffer, &interval);
339         if (ret < 0)
340                 return ret;
341         changed |= ret;
342
343         interval.min = resp.period.min;
344         interval.max = resp.period.max;
345         ret = snd_interval_refine(period, &interval);
346         if (ret < 0)
347                 return ret;
348         changed |= ret;
349
350         return changed;
351 }
352
353 static int alsa_open(struct snd_pcm_substream *substream)
354 {
355         struct xen_snd_front_pcm_instance_info *pcm_instance =
356                         snd_pcm_substream_chip(substream);
357         struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
358         struct snd_pcm_runtime *runtime = substream->runtime;
359         struct xen_snd_front_info *front_info =
360                         pcm_instance->card_info->front_info;
361         struct device *dev = &front_info->xb_dev->dev;
362         int ret;
363
364         /*
365          * Return our HW properties: override defaults with those configured
366          * via XenStore.
367          */
368         runtime->hw = stream->pcm_hw;
369         runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP |
370                               SNDRV_PCM_INFO_MMAP_VALID |
371                               SNDRV_PCM_INFO_DOUBLE |
372                               SNDRV_PCM_INFO_BATCH |
373                               SNDRV_PCM_INFO_NONINTERLEAVED |
374                               SNDRV_PCM_INFO_RESUME |
375                               SNDRV_PCM_INFO_PAUSE);
376         runtime->hw.info |= SNDRV_PCM_INFO_INTERLEAVED;
377
378         stream->evt_pair = &front_info->evt_pairs[stream->index];
379
380         stream->front_info = front_info;
381
382         stream->evt_pair->evt.u.evt.substream = substream;
383
384         stream_clear(stream);
385
386         xen_snd_front_evtchnl_pair_set_connected(stream->evt_pair, true);
387
388         ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
389                                   alsa_hw_rule, stream,
390                                   SNDRV_PCM_HW_PARAM_FORMAT, -1);
391         if (ret) {
392                 dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_FORMAT\n");
393                 return ret;
394         }
395
396         ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
397                                   alsa_hw_rule, stream,
398                                   SNDRV_PCM_HW_PARAM_RATE, -1);
399         if (ret) {
400                 dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_RATE\n");
401                 return ret;
402         }
403
404         ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
405                                   alsa_hw_rule, stream,
406                                   SNDRV_PCM_HW_PARAM_CHANNELS, -1);
407         if (ret) {
408                 dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_CHANNELS\n");
409                 return ret;
410         }
411
412         ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
413                                   alsa_hw_rule, stream,
414                                   SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
415         if (ret) {
416                 dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_PERIOD_SIZE\n");
417                 return ret;
418         }
419
420         ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
421                                   alsa_hw_rule, stream,
422                                   SNDRV_PCM_HW_PARAM_BUFFER_SIZE, -1);
423         if (ret) {
424                 dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_BUFFER_SIZE\n");
425                 return ret;
426         }
427
428         return 0;
429 }
430
431 static int alsa_close(struct snd_pcm_substream *substream)
432 {
433         struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
434
435         xen_snd_front_evtchnl_pair_set_connected(stream->evt_pair, false);
436         return 0;
437 }
438
439 static int shbuf_setup_backstore(struct xen_snd_front_pcm_stream_info *stream,
440                                  size_t buffer_sz)
441 {
442         int i;
443
444         stream->buffer = alloc_pages_exact(buffer_sz, GFP_KERNEL);
445         if (!stream->buffer)
446                 return -ENOMEM;
447
448         stream->buffer_sz = buffer_sz;
449         stream->num_pages = DIV_ROUND_UP(stream->buffer_sz, PAGE_SIZE);
450         stream->pages = kcalloc(stream->num_pages, sizeof(struct page *),
451                                 GFP_KERNEL);
452         if (!stream->pages)
453                 return -ENOMEM;
454
455         for (i = 0; i < stream->num_pages; i++)
456                 stream->pages[i] = virt_to_page(stream->buffer + i * PAGE_SIZE);
457
458         return 0;
459 }
460
461 static int alsa_hw_params(struct snd_pcm_substream *substream,
462                           struct snd_pcm_hw_params *params)
463 {
464         struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
465         struct xen_snd_front_info *front_info = stream->front_info;
466         struct xen_front_pgdir_shbuf_cfg buf_cfg;
467         int ret;
468
469         /*
470          * This callback may be called multiple times,
471          * so free the previously allocated shared buffer if any.
472          */
473         stream_free(stream);
474         ret = shbuf_setup_backstore(stream, params_buffer_bytes(params));
475         if (ret < 0)
476                 goto fail;
477
478         memset(&buf_cfg, 0, sizeof(buf_cfg));
479         buf_cfg.xb_dev = front_info->xb_dev;
480         buf_cfg.pgdir = &stream->shbuf;
481         buf_cfg.num_pages = stream->num_pages;
482         buf_cfg.pages = stream->pages;
483
484         ret = xen_front_pgdir_shbuf_alloc(&buf_cfg);
485         if (ret < 0)
486                 goto fail;
487
488         ret = xen_front_pgdir_shbuf_map(&stream->shbuf);
489         if (ret < 0)
490                 goto fail;
491
492         return 0;
493
494 fail:
495         stream_free(stream);
496         dev_err(&front_info->xb_dev->dev,
497                 "Failed to allocate buffers for stream with index %d\n",
498                 stream->index);
499         return ret;
500 }
501
502 static int alsa_hw_free(struct snd_pcm_substream *substream)
503 {
504         struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
505         int ret;
506
507         ret = xen_snd_front_stream_close(&stream->evt_pair->req);
508         stream_free(stream);
509         return ret;
510 }
511
512 static int alsa_prepare(struct snd_pcm_substream *substream)
513 {
514         struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
515
516         if (!stream->is_open) {
517                 struct snd_pcm_runtime *runtime = substream->runtime;
518                 u8 sndif_format;
519                 int ret;
520
521                 ret = to_sndif_format(runtime->format);
522                 if (ret < 0) {
523                         dev_err(&stream->front_info->xb_dev->dev,
524                                 "Unsupported sample format: %d\n",
525                                 runtime->format);
526                         return ret;
527                 }
528                 sndif_format = ret;
529
530                 ret = xen_snd_front_stream_prepare(&stream->evt_pair->req,
531                                                    &stream->shbuf,
532                                                    sndif_format,
533                                                    runtime->channels,
534                                                    runtime->rate,
535                                                    snd_pcm_lib_buffer_bytes(substream),
536                                                    snd_pcm_lib_period_bytes(substream));
537                 if (ret < 0)
538                         return ret;
539
540                 stream->is_open = true;
541         }
542
543         return 0;
544 }
545
546 static int alsa_trigger(struct snd_pcm_substream *substream, int cmd)
547 {
548         struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
549         int type;
550
551         switch (cmd) {
552         case SNDRV_PCM_TRIGGER_START:
553                 type = XENSND_OP_TRIGGER_START;
554                 break;
555
556         case SNDRV_PCM_TRIGGER_RESUME:
557                 type = XENSND_OP_TRIGGER_RESUME;
558                 break;
559
560         case SNDRV_PCM_TRIGGER_STOP:
561                 type = XENSND_OP_TRIGGER_STOP;
562                 break;
563
564         case SNDRV_PCM_TRIGGER_SUSPEND:
565                 type = XENSND_OP_TRIGGER_PAUSE;
566                 break;
567
568         default:
569                 return -EINVAL;
570         }
571
572         return xen_snd_front_stream_trigger(&stream->evt_pair->req, type);
573 }
574
575 void xen_snd_front_alsa_handle_cur_pos(struct xen_snd_front_evtchnl *evtchnl,
576                                        u64 pos_bytes)
577 {
578         struct snd_pcm_substream *substream = evtchnl->u.evt.substream;
579         struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
580         snd_pcm_uframes_t delta, new_hw_ptr, cur_frame;
581
582         cur_frame = bytes_to_frames(substream->runtime, pos_bytes);
583
584         delta = cur_frame - stream->be_cur_frame;
585         stream->be_cur_frame = cur_frame;
586
587         new_hw_ptr = (snd_pcm_uframes_t)atomic_read(&stream->hw_ptr);
588         new_hw_ptr = (new_hw_ptr + delta) % substream->runtime->buffer_size;
589         atomic_set(&stream->hw_ptr, (int)new_hw_ptr);
590
591         stream->out_frames += delta;
592         if (stream->out_frames > substream->runtime->period_size) {
593                 stream->out_frames %= substream->runtime->period_size;
594                 snd_pcm_period_elapsed(substream);
595         }
596 }
597
598 static snd_pcm_uframes_t alsa_pointer(struct snd_pcm_substream *substream)
599 {
600         struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
601
602         return (snd_pcm_uframes_t)atomic_read(&stream->hw_ptr);
603 }
604
605 static int alsa_pb_copy_user(struct snd_pcm_substream *substream,
606                              int channel, unsigned long pos, void __user *src,
607                              unsigned long count)
608 {
609         struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
610
611         if (unlikely(pos + count > stream->buffer_sz))
612                 return -EINVAL;
613
614         if (copy_from_user(stream->buffer + pos, src, count))
615                 return -EFAULT;
616
617         return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
618 }
619
620 static int alsa_pb_copy_kernel(struct snd_pcm_substream *substream,
621                                int channel, unsigned long pos, void *src,
622                                unsigned long count)
623 {
624         struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
625
626         if (unlikely(pos + count > stream->buffer_sz))
627                 return -EINVAL;
628
629         memcpy(stream->buffer + pos, src, count);
630
631         return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
632 }
633
634 static int alsa_cap_copy_user(struct snd_pcm_substream *substream,
635                               int channel, unsigned long pos, void __user *dst,
636                               unsigned long count)
637 {
638         struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
639         int ret;
640
641         if (unlikely(pos + count > stream->buffer_sz))
642                 return -EINVAL;
643
644         ret = xen_snd_front_stream_read(&stream->evt_pair->req, pos, count);
645         if (ret < 0)
646                 return ret;
647
648         return copy_to_user(dst, stream->buffer + pos, count) ?
649                 -EFAULT : 0;
650 }
651
652 static int alsa_cap_copy_kernel(struct snd_pcm_substream *substream,
653                                 int channel, unsigned long pos, void *dst,
654                                 unsigned long count)
655 {
656         struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
657         int ret;
658
659         if (unlikely(pos + count > stream->buffer_sz))
660                 return -EINVAL;
661
662         ret = xen_snd_front_stream_read(&stream->evt_pair->req, pos, count);
663         if (ret < 0)
664                 return ret;
665
666         memcpy(dst, stream->buffer + pos, count);
667
668         return 0;
669 }
670
671 static int alsa_pb_fill_silence(struct snd_pcm_substream *substream,
672                                 int channel, unsigned long pos,
673                                 unsigned long count)
674 {
675         struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
676
677         if (unlikely(pos + count > stream->buffer_sz))
678                 return -EINVAL;
679
680         memset(stream->buffer + pos, 0, count);
681
682         return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
683 }
684
685 /*
686  * FIXME: The mmaped data transfer is asynchronous and there is no
687  * ack signal from user-space when it is done. This is the
688  * reason it is not implemented in the PV driver as we do need
689  * to know when the buffer can be transferred to the backend.
690  */
691
692 static const struct snd_pcm_ops snd_drv_alsa_playback_ops = {
693         .open           = alsa_open,
694         .close          = alsa_close,
695         .ioctl          = snd_pcm_lib_ioctl,
696         .hw_params      = alsa_hw_params,
697         .hw_free        = alsa_hw_free,
698         .prepare        = alsa_prepare,
699         .trigger        = alsa_trigger,
700         .pointer        = alsa_pointer,
701         .copy_user      = alsa_pb_copy_user,
702         .copy_kernel    = alsa_pb_copy_kernel,
703         .fill_silence   = alsa_pb_fill_silence,
704 };
705
706 static const struct snd_pcm_ops snd_drv_alsa_capture_ops = {
707         .open           = alsa_open,
708         .close          = alsa_close,
709         .ioctl          = snd_pcm_lib_ioctl,
710         .hw_params      = alsa_hw_params,
711         .hw_free        = alsa_hw_free,
712         .prepare        = alsa_prepare,
713         .trigger        = alsa_trigger,
714         .pointer        = alsa_pointer,
715         .copy_user      = alsa_cap_copy_user,
716         .copy_kernel    = alsa_cap_copy_kernel,
717 };
718
719 static int new_pcm_instance(struct xen_snd_front_card_info *card_info,
720                             struct xen_front_cfg_pcm_instance *instance_cfg,
721                             struct xen_snd_front_pcm_instance_info *pcm_instance_info)
722 {
723         struct snd_pcm *pcm;
724         int ret, i;
725
726         dev_dbg(&card_info->front_info->xb_dev->dev,
727                 "New PCM device \"%s\" with id %d playback %d capture %d",
728                 instance_cfg->name,
729                 instance_cfg->device_id,
730                 instance_cfg->num_streams_pb,
731                 instance_cfg->num_streams_cap);
732
733         pcm_instance_info->card_info = card_info;
734
735         pcm_instance_info->pcm_hw = instance_cfg->pcm_hw;
736
737         if (instance_cfg->num_streams_pb) {
738                 pcm_instance_info->streams_pb =
739                                 devm_kcalloc(&card_info->card->card_dev,
740                                              instance_cfg->num_streams_pb,
741                                              sizeof(struct xen_snd_front_pcm_stream_info),
742                                              GFP_KERNEL);
743                 if (!pcm_instance_info->streams_pb)
744                         return -ENOMEM;
745         }
746
747         if (instance_cfg->num_streams_cap) {
748                 pcm_instance_info->streams_cap =
749                                 devm_kcalloc(&card_info->card->card_dev,
750                                              instance_cfg->num_streams_cap,
751                                              sizeof(struct xen_snd_front_pcm_stream_info),
752                                              GFP_KERNEL);
753                 if (!pcm_instance_info->streams_cap)
754                         return -ENOMEM;
755         }
756
757         pcm_instance_info->num_pcm_streams_pb =
758                         instance_cfg->num_streams_pb;
759         pcm_instance_info->num_pcm_streams_cap =
760                         instance_cfg->num_streams_cap;
761
762         for (i = 0; i < pcm_instance_info->num_pcm_streams_pb; i++) {
763                 pcm_instance_info->streams_pb[i].pcm_hw =
764                         instance_cfg->streams_pb[i].pcm_hw;
765                 pcm_instance_info->streams_pb[i].index =
766                         instance_cfg->streams_pb[i].index;
767         }
768
769         for (i = 0; i < pcm_instance_info->num_pcm_streams_cap; i++) {
770                 pcm_instance_info->streams_cap[i].pcm_hw =
771                         instance_cfg->streams_cap[i].pcm_hw;
772                 pcm_instance_info->streams_cap[i].index =
773                         instance_cfg->streams_cap[i].index;
774         }
775
776         ret = snd_pcm_new(card_info->card, instance_cfg->name,
777                           instance_cfg->device_id,
778                           instance_cfg->num_streams_pb,
779                           instance_cfg->num_streams_cap,
780                           &pcm);
781         if (ret < 0)
782                 return ret;
783
784         pcm->private_data = pcm_instance_info;
785         pcm->info_flags = 0;
786         /* we want to handle all PCM operations in non-atomic context */
787         pcm->nonatomic = true;
788         strncpy(pcm->name, "Virtual card PCM", sizeof(pcm->name));
789
790         if (instance_cfg->num_streams_pb)
791                 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,
792                                 &snd_drv_alsa_playback_ops);
793
794         if (instance_cfg->num_streams_cap)
795                 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE,
796                                 &snd_drv_alsa_capture_ops);
797
798         pcm_instance_info->pcm = pcm;
799         return 0;
800 }
801
802 int xen_snd_front_alsa_init(struct xen_snd_front_info *front_info)
803 {
804         struct device *dev = &front_info->xb_dev->dev;
805         struct xen_front_cfg_card *cfg = &front_info->cfg;
806         struct xen_snd_front_card_info *card_info;
807         struct snd_card *card;
808         int ret, i;
809
810         dev_dbg(dev, "Creating virtual sound card\n");
811
812         ret = snd_card_new(dev, 0, XENSND_DRIVER_NAME, THIS_MODULE,
813                            sizeof(struct xen_snd_front_card_info), &card);
814         if (ret < 0)
815                 return ret;
816
817         card_info = card->private_data;
818         card_info->front_info = front_info;
819         front_info->card_info = card_info;
820         card_info->card = card;
821         card_info->pcm_instances =
822                         devm_kcalloc(dev, cfg->num_pcm_instances,
823                                      sizeof(struct xen_snd_front_pcm_instance_info),
824                                      GFP_KERNEL);
825         if (!card_info->pcm_instances) {
826                 ret = -ENOMEM;
827                 goto fail;
828         }
829
830         card_info->num_pcm_instances = cfg->num_pcm_instances;
831         card_info->pcm_hw = cfg->pcm_hw;
832
833         for (i = 0; i < cfg->num_pcm_instances; i++) {
834                 ret = new_pcm_instance(card_info, &cfg->pcm_instances[i],
835                                        &card_info->pcm_instances[i]);
836                 if (ret < 0)
837                         goto fail;
838         }
839
840         strncpy(card->driver, XENSND_DRIVER_NAME, sizeof(card->driver));
841         strncpy(card->shortname, cfg->name_short, sizeof(card->shortname));
842         strncpy(card->longname, cfg->name_long, sizeof(card->longname));
843
844         ret = snd_card_register(card);
845         if (ret < 0)
846                 goto fail;
847
848         return 0;
849
850 fail:
851         snd_card_free(card);
852         return ret;
853 }
854
855 void xen_snd_front_alsa_fini(struct xen_snd_front_info *front_info)
856 {
857         struct xen_snd_front_card_info *card_info;
858         struct snd_card *card;
859
860         card_info = front_info->card_info;
861         if (!card_info)
862                 return;
863
864         card = card_info->card;
865         if (!card)
866                 return;
867
868         dev_dbg(&front_info->xb_dev->dev, "Removing virtual sound card %d\n",
869                 card->number);
870         snd_card_free(card);
871
872         /* Card_info will be freed when destroying front_info->xb_dev->dev. */
873         card_info->card = NULL;
874 }