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 <xen/xenbus.h>
12 
13 #include <xen/interface/io/sndif.h>
14 
15 #include "xen_snd_front.h"
16 #include "xen_snd_front_cfg.h"
17 
18 /* Maximum number of supported streams. */
19 #define VSND_MAX_STREAM		8
20 
21 struct cfg_hw_sample_rate {
22 	const char *name;
23 	unsigned int mask;
24 	unsigned int value;
25 };
26 
27 static const struct cfg_hw_sample_rate CFG_HW_SUPPORTED_RATES[] = {
28 	{ .name = "5512",   .mask = SNDRV_PCM_RATE_5512,   .value = 5512 },
29 	{ .name = "8000",   .mask = SNDRV_PCM_RATE_8000,   .value = 8000 },
30 	{ .name = "11025",  .mask = SNDRV_PCM_RATE_11025,  .value = 11025 },
31 	{ .name = "16000",  .mask = SNDRV_PCM_RATE_16000,  .value = 16000 },
32 	{ .name = "22050",  .mask = SNDRV_PCM_RATE_22050,  .value = 22050 },
33 	{ .name = "32000",  .mask = SNDRV_PCM_RATE_32000,  .value = 32000 },
34 	{ .name = "44100",  .mask = SNDRV_PCM_RATE_44100,  .value = 44100 },
35 	{ .name = "48000",  .mask = SNDRV_PCM_RATE_48000,  .value = 48000 },
36 	{ .name = "64000",  .mask = SNDRV_PCM_RATE_64000,  .value = 64000 },
37 	{ .name = "96000",  .mask = SNDRV_PCM_RATE_96000,  .value = 96000 },
38 	{ .name = "176400", .mask = SNDRV_PCM_RATE_176400, .value = 176400 },
39 	{ .name = "192000", .mask = SNDRV_PCM_RATE_192000, .value = 192000 },
40 };
41 
42 struct cfg_hw_sample_format {
43 	const char *name;
44 	u64 mask;
45 };
46 
47 static const struct cfg_hw_sample_format CFG_HW_SUPPORTED_FORMATS[] = {
48 	{
49 		.name = XENSND_PCM_FORMAT_U8_STR,
50 		.mask = SNDRV_PCM_FMTBIT_U8
51 	},
52 	{
53 		.name = XENSND_PCM_FORMAT_S8_STR,
54 		.mask = SNDRV_PCM_FMTBIT_S8
55 	},
56 	{
57 		.name = XENSND_PCM_FORMAT_U16_LE_STR,
58 		.mask = SNDRV_PCM_FMTBIT_U16_LE
59 	},
60 	{
61 		.name = XENSND_PCM_FORMAT_U16_BE_STR,
62 		.mask = SNDRV_PCM_FMTBIT_U16_BE
63 	},
64 	{
65 		.name = XENSND_PCM_FORMAT_S16_LE_STR,
66 		.mask = SNDRV_PCM_FMTBIT_S16_LE
67 	},
68 	{
69 		.name = XENSND_PCM_FORMAT_S16_BE_STR,
70 		.mask = SNDRV_PCM_FMTBIT_S16_BE
71 	},
72 	{
73 		.name = XENSND_PCM_FORMAT_U24_LE_STR,
74 		.mask = SNDRV_PCM_FMTBIT_U24_LE
75 	},
76 	{
77 		.name = XENSND_PCM_FORMAT_U24_BE_STR,
78 		.mask = SNDRV_PCM_FMTBIT_U24_BE
79 	},
80 	{
81 		.name = XENSND_PCM_FORMAT_S24_LE_STR,
82 		.mask = SNDRV_PCM_FMTBIT_S24_LE
83 	},
84 	{
85 		.name = XENSND_PCM_FORMAT_S24_BE_STR,
86 		.mask = SNDRV_PCM_FMTBIT_S24_BE
87 	},
88 	{
89 		.name = XENSND_PCM_FORMAT_U32_LE_STR,
90 		.mask = SNDRV_PCM_FMTBIT_U32_LE
91 	},
92 	{
93 		.name = XENSND_PCM_FORMAT_U32_BE_STR,
94 		.mask = SNDRV_PCM_FMTBIT_U32_BE
95 	},
96 	{
97 		.name = XENSND_PCM_FORMAT_S32_LE_STR,
98 		.mask = SNDRV_PCM_FMTBIT_S32_LE
99 	},
100 	{
101 		.name = XENSND_PCM_FORMAT_S32_BE_STR,
102 		.mask = SNDRV_PCM_FMTBIT_S32_BE
103 	},
104 	{
105 		.name = XENSND_PCM_FORMAT_A_LAW_STR,
106 		.mask = SNDRV_PCM_FMTBIT_A_LAW
107 	},
108 	{
109 		.name = XENSND_PCM_FORMAT_MU_LAW_STR,
110 		.mask = SNDRV_PCM_FMTBIT_MU_LAW
111 	},
112 	{
113 		.name = XENSND_PCM_FORMAT_F32_LE_STR,
114 		.mask = SNDRV_PCM_FMTBIT_FLOAT_LE
115 	},
116 	{
117 		.name = XENSND_PCM_FORMAT_F32_BE_STR,
118 		.mask = SNDRV_PCM_FMTBIT_FLOAT_BE
119 	},
120 	{
121 		.name = XENSND_PCM_FORMAT_F64_LE_STR,
122 		.mask = SNDRV_PCM_FMTBIT_FLOAT64_LE
123 	},
124 	{
125 		.name = XENSND_PCM_FORMAT_F64_BE_STR,
126 		.mask = SNDRV_PCM_FMTBIT_FLOAT64_BE
127 	},
128 	{
129 		.name = XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE_STR,
130 		.mask = SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE
131 	},
132 	{
133 		.name = XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE_STR,
134 		.mask = SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_BE
135 	},
136 	{
137 		.name = XENSND_PCM_FORMAT_IMA_ADPCM_STR,
138 		.mask = SNDRV_PCM_FMTBIT_IMA_ADPCM
139 	},
140 	{
141 		.name = XENSND_PCM_FORMAT_MPEG_STR,
142 		.mask = SNDRV_PCM_FMTBIT_MPEG
143 	},
144 	{
145 		.name = XENSND_PCM_FORMAT_GSM_STR,
146 		.mask = SNDRV_PCM_FMTBIT_GSM
147 	},
148 };
149 
cfg_hw_rates(char * list,unsigned int len,const char * path,struct snd_pcm_hardware * pcm_hw)150 static void cfg_hw_rates(char *list, unsigned int len,
151 			 const char *path, struct snd_pcm_hardware *pcm_hw)
152 {
153 	char *cur_rate;
154 	unsigned int cur_mask;
155 	unsigned int cur_value;
156 	unsigned int rates;
157 	unsigned int rate_min;
158 	unsigned int rate_max;
159 	int i;
160 
161 	rates = 0;
162 	rate_min = -1;
163 	rate_max = 0;
164 	while ((cur_rate = strsep(&list, XENSND_LIST_SEPARATOR))) {
165 		for (i = 0; i < ARRAY_SIZE(CFG_HW_SUPPORTED_RATES); i++)
166 			if (!strncasecmp(cur_rate,
167 					 CFG_HW_SUPPORTED_RATES[i].name,
168 					 XENSND_SAMPLE_RATE_MAX_LEN)) {
169 				cur_mask = CFG_HW_SUPPORTED_RATES[i].mask;
170 				cur_value = CFG_HW_SUPPORTED_RATES[i].value;
171 				rates |= cur_mask;
172 				if (rate_min > cur_value)
173 					rate_min = cur_value;
174 				if (rate_max < cur_value)
175 					rate_max = cur_value;
176 			}
177 	}
178 
179 	if (rates) {
180 		pcm_hw->rates = rates;
181 		pcm_hw->rate_min = rate_min;
182 		pcm_hw->rate_max = rate_max;
183 	}
184 }
185 
cfg_formats(char * list,unsigned int len,const char * path,struct snd_pcm_hardware * pcm_hw)186 static void cfg_formats(char *list, unsigned int len,
187 			const char *path, struct snd_pcm_hardware *pcm_hw)
188 {
189 	u64 formats;
190 	char *cur_format;
191 	int i;
192 
193 	formats = 0;
194 	while ((cur_format = strsep(&list, XENSND_LIST_SEPARATOR))) {
195 		for (i = 0; i < ARRAY_SIZE(CFG_HW_SUPPORTED_FORMATS); i++)
196 			if (!strncasecmp(cur_format,
197 					 CFG_HW_SUPPORTED_FORMATS[i].name,
198 					 XENSND_SAMPLE_FORMAT_MAX_LEN))
199 				formats |= CFG_HW_SUPPORTED_FORMATS[i].mask;
200 	}
201 
202 	if (formats)
203 		pcm_hw->formats = formats;
204 }
205 
206 #define MAX_BUFFER_SIZE		(64 * 1024)
207 #define MIN_PERIOD_SIZE		64
208 #define MAX_PERIOD_SIZE		MAX_BUFFER_SIZE
209 #define USE_FORMATS		(SNDRV_PCM_FMTBIT_U8 | \
210 				 SNDRV_PCM_FMTBIT_S16_LE)
211 #define USE_RATE		(SNDRV_PCM_RATE_CONTINUOUS | \
212 				 SNDRV_PCM_RATE_8000_48000)
213 #define USE_RATE_MIN		5512
214 #define USE_RATE_MAX		48000
215 #define USE_CHANNELS_MIN	1
216 #define USE_CHANNELS_MAX	2
217 #define USE_PERIODS_MIN		2
218 #define USE_PERIODS_MAX		(MAX_BUFFER_SIZE / MIN_PERIOD_SIZE)
219 
220 static const struct snd_pcm_hardware SND_DRV_PCM_HW_DEFAULT = {
221 	.info = (SNDRV_PCM_INFO_MMAP |
222 		 SNDRV_PCM_INFO_INTERLEAVED |
223 		 SNDRV_PCM_INFO_RESUME |
224 		 SNDRV_PCM_INFO_MMAP_VALID),
225 	.formats = USE_FORMATS,
226 	.rates = USE_RATE,
227 	.rate_min = USE_RATE_MIN,
228 	.rate_max = USE_RATE_MAX,
229 	.channels_min = USE_CHANNELS_MIN,
230 	.channels_max = USE_CHANNELS_MAX,
231 	.buffer_bytes_max = MAX_BUFFER_SIZE,
232 	.period_bytes_min = MIN_PERIOD_SIZE,
233 	.period_bytes_max = MAX_PERIOD_SIZE,
234 	.periods_min = USE_PERIODS_MIN,
235 	.periods_max = USE_PERIODS_MAX,
236 	.fifo_size = 0,
237 };
238 
cfg_read_pcm_hw(const char * path,struct snd_pcm_hardware * parent_pcm_hw,struct snd_pcm_hardware * pcm_hw)239 static void cfg_read_pcm_hw(const char *path,
240 			    struct snd_pcm_hardware *parent_pcm_hw,
241 			    struct snd_pcm_hardware *pcm_hw)
242 {
243 	char *list;
244 	int val;
245 	size_t buf_sz;
246 	unsigned int len;
247 
248 	/* Inherit parent's PCM HW and read overrides from XenStore. */
249 	if (parent_pcm_hw)
250 		*pcm_hw = *parent_pcm_hw;
251 	else
252 		*pcm_hw = SND_DRV_PCM_HW_DEFAULT;
253 
254 	val = xenbus_read_unsigned(path, XENSND_FIELD_CHANNELS_MIN, 0);
255 	if (val)
256 		pcm_hw->channels_min = val;
257 
258 	val = xenbus_read_unsigned(path, XENSND_FIELD_CHANNELS_MAX, 0);
259 	if (val)
260 		pcm_hw->channels_max = val;
261 
262 	list = xenbus_read(XBT_NIL, path, XENSND_FIELD_SAMPLE_RATES, &len);
263 	if (!IS_ERR(list)) {
264 		cfg_hw_rates(list, len, path, pcm_hw);
265 		kfree(list);
266 	}
267 
268 	list = xenbus_read(XBT_NIL, path, XENSND_FIELD_SAMPLE_FORMATS, &len);
269 	if (!IS_ERR(list)) {
270 		cfg_formats(list, len, path, pcm_hw);
271 		kfree(list);
272 	}
273 
274 	buf_sz = xenbus_read_unsigned(path, XENSND_FIELD_BUFFER_SIZE, 0);
275 	if (buf_sz)
276 		pcm_hw->buffer_bytes_max = buf_sz;
277 
278 	/* Update configuration to match new values. */
279 	if (pcm_hw->channels_min > pcm_hw->channels_max)
280 		pcm_hw->channels_min = pcm_hw->channels_max;
281 
282 	if (pcm_hw->rate_min > pcm_hw->rate_max)
283 		pcm_hw->rate_min = pcm_hw->rate_max;
284 
285 	pcm_hw->period_bytes_max = pcm_hw->buffer_bytes_max;
286 
287 	pcm_hw->periods_max = pcm_hw->period_bytes_max /
288 		pcm_hw->period_bytes_min;
289 }
290 
cfg_get_stream_type(const char * path,int index,int * num_pb,int * num_cap)291 static int cfg_get_stream_type(const char *path, int index,
292 			       int *num_pb, int *num_cap)
293 {
294 	char *str = NULL;
295 	char *stream_path;
296 	int ret;
297 
298 	*num_pb = 0;
299 	*num_cap = 0;
300 	stream_path = kasprintf(GFP_KERNEL, "%s/%d", path, index);
301 	if (!stream_path) {
302 		ret = -ENOMEM;
303 		goto fail;
304 	}
305 
306 	str = xenbus_read(XBT_NIL, stream_path, XENSND_FIELD_TYPE, NULL);
307 	if (IS_ERR(str)) {
308 		ret = PTR_ERR(str);
309 		str = NULL;
310 		goto fail;
311 	}
312 
313 	if (!strncasecmp(str, XENSND_STREAM_TYPE_PLAYBACK,
314 			 sizeof(XENSND_STREAM_TYPE_PLAYBACK))) {
315 		(*num_pb)++;
316 	} else if (!strncasecmp(str, XENSND_STREAM_TYPE_CAPTURE,
317 			      sizeof(XENSND_STREAM_TYPE_CAPTURE))) {
318 		(*num_cap)++;
319 	} else {
320 		ret = -EINVAL;
321 		goto fail;
322 	}
323 	ret = 0;
324 
325 fail:
326 	kfree(stream_path);
327 	kfree(str);
328 	return ret;
329 }
330 
cfg_stream(struct xen_snd_front_info * front_info,struct xen_front_cfg_pcm_instance * pcm_instance,const char * path,int index,int * cur_pb,int * cur_cap,int * stream_cnt)331 static int cfg_stream(struct xen_snd_front_info *front_info,
332 		      struct xen_front_cfg_pcm_instance *pcm_instance,
333 		      const char *path, int index, int *cur_pb, int *cur_cap,
334 		      int *stream_cnt)
335 {
336 	char *str = NULL;
337 	char *stream_path;
338 	struct xen_front_cfg_stream *stream;
339 	int ret;
340 
341 	stream_path = devm_kasprintf(&front_info->xb_dev->dev,
342 				     GFP_KERNEL, "%s/%d", path, index);
343 	if (!stream_path) {
344 		ret = -ENOMEM;
345 		goto fail;
346 	}
347 
348 	str = xenbus_read(XBT_NIL, stream_path, XENSND_FIELD_TYPE, NULL);
349 	if (IS_ERR(str)) {
350 		ret = PTR_ERR(str);
351 		str = NULL;
352 		goto fail;
353 	}
354 
355 	if (!strncasecmp(str, XENSND_STREAM_TYPE_PLAYBACK,
356 			 sizeof(XENSND_STREAM_TYPE_PLAYBACK))) {
357 		stream = &pcm_instance->streams_pb[(*cur_pb)++];
358 	} else if (!strncasecmp(str, XENSND_STREAM_TYPE_CAPTURE,
359 			      sizeof(XENSND_STREAM_TYPE_CAPTURE))) {
360 		stream = &pcm_instance->streams_cap[(*cur_cap)++];
361 	} else {
362 		ret = -EINVAL;
363 		goto fail;
364 	}
365 
366 	/* Get next stream index. */
367 	stream->index = (*stream_cnt)++;
368 	stream->xenstore_path = stream_path;
369 	/*
370 	 * Check XenStore if PCM HW configuration exists for this stream
371 	 * and update if so, e.g. we inherit all values from device's PCM HW,
372 	 * but can still override some of the values for the stream.
373 	 */
374 	cfg_read_pcm_hw(stream->xenstore_path,
375 			&pcm_instance->pcm_hw, &stream->pcm_hw);
376 	ret = 0;
377 
378 fail:
379 	kfree(str);
380 	return ret;
381 }
382 
cfg_device(struct xen_snd_front_info * front_info,struct xen_front_cfg_pcm_instance * pcm_instance,struct snd_pcm_hardware * parent_pcm_hw,const char * path,int node_index,int * stream_cnt)383 static int cfg_device(struct xen_snd_front_info *front_info,
384 		      struct xen_front_cfg_pcm_instance *pcm_instance,
385 		      struct snd_pcm_hardware *parent_pcm_hw,
386 		      const char *path, int node_index, int *stream_cnt)
387 {
388 	char *str;
389 	char *device_path;
390 	int ret, i, num_streams;
391 	int num_pb, num_cap;
392 	int cur_pb, cur_cap;
393 	char node[3];
394 
395 	device_path = kasprintf(GFP_KERNEL, "%s/%d", path, node_index);
396 	if (!device_path)
397 		return -ENOMEM;
398 
399 	str = xenbus_read(XBT_NIL, device_path, XENSND_FIELD_DEVICE_NAME, NULL);
400 	if (!IS_ERR(str)) {
401 		strlcpy(pcm_instance->name, str, sizeof(pcm_instance->name));
402 		kfree(str);
403 	}
404 
405 	pcm_instance->device_id = node_index;
406 
407 	/*
408 	 * Check XenStore if PCM HW configuration exists for this device
409 	 * and update if so, e.g. we inherit all values from card's PCM HW,
410 	 * but can still override some of the values for the device.
411 	 */
412 	cfg_read_pcm_hw(device_path, parent_pcm_hw, &pcm_instance->pcm_hw);
413 
414 	/* Find out how many streams were configured in Xen store. */
415 	num_streams = 0;
416 	do {
417 		snprintf(node, sizeof(node), "%d", num_streams);
418 		if (!xenbus_exists(XBT_NIL, device_path, node))
419 			break;
420 
421 		num_streams++;
422 	} while (num_streams < VSND_MAX_STREAM);
423 
424 	pcm_instance->num_streams_pb = 0;
425 	pcm_instance->num_streams_cap = 0;
426 	/* Get number of playback and capture streams. */
427 	for (i = 0; i < num_streams; i++) {
428 		ret = cfg_get_stream_type(device_path, i, &num_pb, &num_cap);
429 		if (ret < 0)
430 			goto fail;
431 
432 		pcm_instance->num_streams_pb += num_pb;
433 		pcm_instance->num_streams_cap += num_cap;
434 	}
435 
436 	if (pcm_instance->num_streams_pb) {
437 		pcm_instance->streams_pb =
438 				devm_kcalloc(&front_info->xb_dev->dev,
439 					     pcm_instance->num_streams_pb,
440 					     sizeof(struct xen_front_cfg_stream),
441 					     GFP_KERNEL);
442 		if (!pcm_instance->streams_pb) {
443 			ret = -ENOMEM;
444 			goto fail;
445 		}
446 	}
447 
448 	if (pcm_instance->num_streams_cap) {
449 		pcm_instance->streams_cap =
450 				devm_kcalloc(&front_info->xb_dev->dev,
451 					     pcm_instance->num_streams_cap,
452 					     sizeof(struct xen_front_cfg_stream),
453 					     GFP_KERNEL);
454 		if (!pcm_instance->streams_cap) {
455 			ret = -ENOMEM;
456 			goto fail;
457 		}
458 	}
459 
460 	cur_pb = 0;
461 	cur_cap = 0;
462 	for (i = 0; i < num_streams; i++) {
463 		ret = cfg_stream(front_info, pcm_instance, device_path, i,
464 				 &cur_pb, &cur_cap, stream_cnt);
465 		if (ret < 0)
466 			goto fail;
467 	}
468 	ret = 0;
469 
470 fail:
471 	kfree(device_path);
472 	return ret;
473 }
474 
xen_snd_front_cfg_card(struct xen_snd_front_info * front_info,int * stream_cnt)475 int xen_snd_front_cfg_card(struct xen_snd_front_info *front_info,
476 			   int *stream_cnt)
477 {
478 	struct xenbus_device *xb_dev = front_info->xb_dev;
479 	struct xen_front_cfg_card *cfg = &front_info->cfg;
480 	int ret, num_devices, i;
481 	char node[3];
482 
483 	*stream_cnt = 0;
484 	num_devices = 0;
485 	do {
486 		snprintf(node, sizeof(node), "%d", num_devices);
487 		if (!xenbus_exists(XBT_NIL, xb_dev->nodename, node))
488 			break;
489 
490 		num_devices++;
491 	} while (num_devices < SNDRV_PCM_DEVICES);
492 
493 	if (!num_devices) {
494 		dev_warn(&xb_dev->dev,
495 			 "No devices configured for sound card at %s\n",
496 			 xb_dev->nodename);
497 		return -ENODEV;
498 	}
499 
500 	/* Start from default PCM HW configuration for the card. */
501 	cfg_read_pcm_hw(xb_dev->nodename, NULL, &cfg->pcm_hw);
502 
503 	cfg->pcm_instances =
504 			devm_kcalloc(&front_info->xb_dev->dev, num_devices,
505 				     sizeof(struct xen_front_cfg_pcm_instance),
506 				     GFP_KERNEL);
507 	if (!cfg->pcm_instances)
508 		return -ENOMEM;
509 
510 	for (i = 0; i < num_devices; i++) {
511 		ret = cfg_device(front_info, &cfg->pcm_instances[i],
512 				 &cfg->pcm_hw, xb_dev->nodename, i, stream_cnt);
513 		if (ret < 0)
514 			return ret;
515 	}
516 	cfg->num_pcm_instances = num_devices;
517 	return 0;
518 }
519 
520