1 // SPDX-License-Identifier: GPL-2.0-or-later
2 //
3 // Special handling for implicit feedback mode
4 //
5 
6 #include <linux/init.h>
7 #include <linux/usb.h>
8 #include <linux/usb/audio.h>
9 #include <linux/usb/audio-v2.h>
10 
11 #include <sound/core.h>
12 #include <sound/pcm.h>
13 #include <sound/pcm_params.h>
14 
15 #include "usbaudio.h"
16 #include "card.h"
17 #include "helper.h"
18 #include "pcm.h"
19 #include "implicit.h"
20 
21 enum {
22 	IMPLICIT_FB_NONE,
23 	IMPLICIT_FB_GENERIC,
24 	IMPLICIT_FB_FIXED,
25 	IMPLICIT_FB_BOTH,	/* generic playback + capture (for BOSS) */
26 };
27 
28 struct snd_usb_implicit_fb_match {
29 	unsigned int id;
30 	unsigned int iface_class;
31 	unsigned int ep_num;
32 	unsigned int iface;
33 	int type;
34 };
35 
36 #define IMPLICIT_FB_GENERIC_DEV(vend, prod) \
37 	{ .id = USB_ID(vend, prod), .type = IMPLICIT_FB_GENERIC }
38 #define IMPLICIT_FB_FIXED_DEV(vend, prod, ep, ifnum) \
39 	{ .id = USB_ID(vend, prod), .type = IMPLICIT_FB_FIXED, .ep_num = (ep),\
40 	    .iface = (ifnum) }
41 #define IMPLICIT_FB_BOTH_DEV(vend, prod, ep, ifnum) \
42 	{ .id = USB_ID(vend, prod), .type = IMPLICIT_FB_BOTH, .ep_num = (ep),\
43 	    .iface = (ifnum) }
44 #define IMPLICIT_FB_SKIP_DEV(vend, prod) \
45 	{ .id = USB_ID(vend, prod), .type = IMPLICIT_FB_NONE }
46 
47 /* Implicit feedback quirk table for playback */
48 static const struct snd_usb_implicit_fb_match playback_implicit_fb_quirks[] = {
49 	/* Fixed EP */
50 	/* FIXME: check the availability of generic matching */
51 	IMPLICIT_FB_FIXED_DEV(0x0763, 0x2030, 0x81, 3), /* M-Audio Fast Track C400 */
52 	IMPLICIT_FB_FIXED_DEV(0x0763, 0x2031, 0x81, 3), /* M-Audio Fast Track C600 */
53 	IMPLICIT_FB_FIXED_DEV(0x0763, 0x2080, 0x81, 2), /* M-Audio FastTrack Ultra */
54 	IMPLICIT_FB_FIXED_DEV(0x0763, 0x2081, 0x81, 2), /* M-Audio FastTrack Ultra */
55 	IMPLICIT_FB_FIXED_DEV(0x2466, 0x8010, 0x81, 2), /* Fractal Audio Axe-Fx III */
56 	IMPLICIT_FB_FIXED_DEV(0x31e9, 0x0001, 0x81, 2), /* Solid State Logic SSL2 */
57 	IMPLICIT_FB_FIXED_DEV(0x31e9, 0x0002, 0x81, 2), /* Solid State Logic SSL2+ */
58 	IMPLICIT_FB_FIXED_DEV(0x0499, 0x172f, 0x81, 2), /* Steinberg UR22C */
59 	IMPLICIT_FB_FIXED_DEV(0x0d9a, 0x00df, 0x81, 2), /* RTX6001 */
60 	IMPLICIT_FB_FIXED_DEV(0x22f0, 0x0006, 0x81, 3), /* Allen&Heath Qu-16 */
61 	IMPLICIT_FB_FIXED_DEV(0x1686, 0xf029, 0x82, 2), /* Zoom UAC-2 */
62 	IMPLICIT_FB_FIXED_DEV(0x2466, 0x8003, 0x86, 2), /* Fractal Audio Axe-Fx II */
63 	IMPLICIT_FB_FIXED_DEV(0x0499, 0x172a, 0x86, 2), /* Yamaha MODX */
64 
65 	/* Special matching */
66 	{ .id = USB_ID(0x07fd, 0x0004), .iface_class = USB_CLASS_AUDIO,
67 	  .type = IMPLICIT_FB_NONE },		/* MicroBook IIc */
68 	/* ep = 0x84, ifnum = 0 */
69 	{ .id = USB_ID(0x07fd, 0x0004), .iface_class = USB_CLASS_VENDOR_SPEC,
70 	  .type = IMPLICIT_FB_FIXED,
71 	  .ep_num = 0x84, .iface = 0 },		/* MOTU MicroBook II */
72 
73 	{} /* terminator */
74 };
75 
76 /* Implicit feedback quirk table for capture: only FIXED type */
77 static const struct snd_usb_implicit_fb_match capture_implicit_fb_quirks[] = {
78 	{} /* terminator */
79 };
80 
81 /* set up sync EP information on the audioformat */
add_implicit_fb_sync_ep(struct snd_usb_audio * chip,struct audioformat * fmt,int ep,int ep_idx,int ifnum,const struct usb_host_interface * alts)82 static int add_implicit_fb_sync_ep(struct snd_usb_audio *chip,
83 				   struct audioformat *fmt,
84 				   int ep, int ep_idx, int ifnum,
85 				   const struct usb_host_interface *alts)
86 {
87 	struct usb_interface *iface;
88 
89 	if (!alts) {
90 		iface = usb_ifnum_to_if(chip->dev, ifnum);
91 		if (!iface || iface->num_altsetting < 2)
92 			return 0;
93 		alts = &iface->altsetting[1];
94 	}
95 
96 	fmt->sync_ep = ep;
97 	fmt->sync_iface = ifnum;
98 	fmt->sync_altsetting = alts->desc.bAlternateSetting;
99 	fmt->sync_ep_idx = ep_idx;
100 	fmt->implicit_fb = 1;
101 	usb_audio_dbg(chip,
102 		      "%d:%d: added %s implicit_fb sync_ep %x, iface %d:%d\n",
103 		      fmt->iface, fmt->altsetting,
104 		      (ep & USB_DIR_IN) ? "playback" : "capture",
105 		      fmt->sync_ep, fmt->sync_iface, fmt->sync_altsetting);
106 	return 1;
107 }
108 
109 /* Check whether the given UAC2 iface:altset points to an implicit fb source */
add_generic_uac2_implicit_fb(struct snd_usb_audio * chip,struct audioformat * fmt,unsigned int ifnum,unsigned int altsetting)110 static int add_generic_uac2_implicit_fb(struct snd_usb_audio *chip,
111 					struct audioformat *fmt,
112 					unsigned int ifnum,
113 					unsigned int altsetting)
114 {
115 	struct usb_host_interface *alts;
116 	struct usb_endpoint_descriptor *epd;
117 
118 	alts = snd_usb_get_host_interface(chip, ifnum, altsetting);
119 	if (!alts)
120 		return 0;
121 	if (alts->desc.bInterfaceClass != USB_CLASS_AUDIO ||
122 	    alts->desc.bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING ||
123 	    alts->desc.bInterfaceProtocol != UAC_VERSION_2 ||
124 	    alts->desc.bNumEndpoints < 1)
125 		return 0;
126 	epd = get_endpoint(alts, 0);
127 	if (!usb_endpoint_is_isoc_in(epd) ||
128 	    (epd->bmAttributes & USB_ENDPOINT_USAGE_MASK) !=
129 					USB_ENDPOINT_USAGE_IMPLICIT_FB)
130 		return 0;
131 	return add_implicit_fb_sync_ep(chip, fmt, epd->bEndpointAddress, 0,
132 				       ifnum, alts);
133 }
134 
roland_sanity_check_iface(struct usb_host_interface * alts)135 static bool roland_sanity_check_iface(struct usb_host_interface *alts)
136 {
137 	if (alts->desc.bInterfaceClass != USB_CLASS_VENDOR_SPEC ||
138 	    (alts->desc.bInterfaceSubClass != 2 &&
139 	     alts->desc.bInterfaceProtocol != 2) ||
140 	    alts->desc.bNumEndpoints < 1)
141 		return false;
142 	return true;
143 }
144 
145 /* Like the UAC2 case above, but specific to Roland with vendor class and hack */
add_roland_implicit_fb(struct snd_usb_audio * chip,struct audioformat * fmt,struct usb_host_interface * alts)146 static int add_roland_implicit_fb(struct snd_usb_audio *chip,
147 				  struct audioformat *fmt,
148 				  struct usb_host_interface *alts)
149 {
150 	struct usb_endpoint_descriptor *epd;
151 
152 	if (!roland_sanity_check_iface(alts))
153 		return 0;
154 	/* only when both streams are with ASYNC type */
155 	epd = get_endpoint(alts, 0);
156 	if (!usb_endpoint_is_isoc_out(epd) ||
157 	    (epd->bmAttributes & USB_ENDPOINT_SYNCTYPE) != USB_ENDPOINT_SYNC_ASYNC)
158 		return 0;
159 
160 	/* check capture EP */
161 	alts = snd_usb_get_host_interface(chip,
162 					  alts->desc.bInterfaceNumber + 1,
163 					  alts->desc.bAlternateSetting);
164 	if (!alts || !roland_sanity_check_iface(alts))
165 		return 0;
166 	epd = get_endpoint(alts, 0);
167 	if (!usb_endpoint_is_isoc_in(epd) ||
168 	    (epd->bmAttributes & USB_ENDPOINT_SYNCTYPE) != USB_ENDPOINT_SYNC_ASYNC)
169 		return 0;
170 	chip->quirk_flags |= QUIRK_FLAG_PLAYBACK_FIRST;
171 	return add_implicit_fb_sync_ep(chip, fmt, epd->bEndpointAddress, 0,
172 				       alts->desc.bInterfaceNumber, alts);
173 }
174 
175 /* capture quirk for Roland device; always full-duplex */
add_roland_capture_quirk(struct snd_usb_audio * chip,struct audioformat * fmt,struct usb_host_interface * alts)176 static int add_roland_capture_quirk(struct snd_usb_audio *chip,
177 				    struct audioformat *fmt,
178 				    struct usb_host_interface *alts)
179 {
180 	struct usb_endpoint_descriptor *epd;
181 
182 	if (!roland_sanity_check_iface(alts))
183 		return 0;
184 	epd = get_endpoint(alts, 0);
185 	if (!usb_endpoint_is_isoc_in(epd) ||
186 	    (epd->bmAttributes & USB_ENDPOINT_SYNCTYPE) != USB_ENDPOINT_SYNC_ASYNC)
187 		return 0;
188 
189 	alts = snd_usb_get_host_interface(chip,
190 					  alts->desc.bInterfaceNumber - 1,
191 					  alts->desc.bAlternateSetting);
192 	if (!alts || !roland_sanity_check_iface(alts))
193 		return 0;
194 	epd = get_endpoint(alts, 0);
195 	if (!usb_endpoint_is_isoc_out(epd))
196 		return 0;
197 	return add_implicit_fb_sync_ep(chip, fmt, epd->bEndpointAddress, 0,
198 				       alts->desc.bInterfaceNumber, alts);
199 }
200 
201 /* Playback and capture EPs on Pioneer devices share the same iface/altset
202  * for the implicit feedback operation
203  */
is_pioneer_implicit_fb(struct snd_usb_audio * chip,struct usb_host_interface * alts)204 static bool is_pioneer_implicit_fb(struct snd_usb_audio *chip,
205 				   struct usb_host_interface *alts)
206 
207 {
208 	struct usb_endpoint_descriptor *epd;
209 
210 	if (USB_ID_VENDOR(chip->usb_id) != 0x2b73 &&
211 	    USB_ID_VENDOR(chip->usb_id) != 0x08e4)
212 		return false;
213 	if (alts->desc.bInterfaceClass != USB_CLASS_VENDOR_SPEC)
214 		return false;
215 	if (alts->desc.bNumEndpoints != 2)
216 		return false;
217 
218 	epd = get_endpoint(alts, 0);
219 	if (!usb_endpoint_is_isoc_out(epd) ||
220 	    (epd->bmAttributes & USB_ENDPOINT_SYNCTYPE) != USB_ENDPOINT_SYNC_ASYNC)
221 		return false;
222 
223 	epd = get_endpoint(alts, 1);
224 	if (!usb_endpoint_is_isoc_in(epd) ||
225 	    (epd->bmAttributes & USB_ENDPOINT_SYNCTYPE) != USB_ENDPOINT_SYNC_ASYNC ||
226 	    ((epd->bmAttributes & USB_ENDPOINT_USAGE_MASK) !=
227 	     USB_ENDPOINT_USAGE_DATA &&
228 	     (epd->bmAttributes & USB_ENDPOINT_USAGE_MASK) !=
229 	     USB_ENDPOINT_USAGE_IMPLICIT_FB))
230 		return false;
231 
232 	return true;
233 }
234 
__add_generic_implicit_fb(struct snd_usb_audio * chip,struct audioformat * fmt,int iface,int altset)235 static int __add_generic_implicit_fb(struct snd_usb_audio *chip,
236 				     struct audioformat *fmt,
237 				     int iface, int altset)
238 {
239 	struct usb_host_interface *alts;
240 	struct usb_endpoint_descriptor *epd;
241 
242 	alts = snd_usb_get_host_interface(chip, iface, altset);
243 	if (!alts)
244 		return 0;
245 
246 	if ((alts->desc.bInterfaceClass != USB_CLASS_VENDOR_SPEC &&
247 	     alts->desc.bInterfaceClass != USB_CLASS_AUDIO) ||
248 	    alts->desc.bNumEndpoints < 1)
249 		return 0;
250 	epd = get_endpoint(alts, 0);
251 	if (!usb_endpoint_is_isoc_in(epd) ||
252 	    (epd->bmAttributes & USB_ENDPOINT_SYNCTYPE) != USB_ENDPOINT_SYNC_ASYNC)
253 		return 0;
254 	return add_implicit_fb_sync_ep(chip, fmt, epd->bEndpointAddress, 0,
255 				       iface, alts);
256 }
257 
258 /* More generic quirk: look for the sync EP next to the data EP */
add_generic_implicit_fb(struct snd_usb_audio * chip,struct audioformat * fmt,struct usb_host_interface * alts)259 static int add_generic_implicit_fb(struct snd_usb_audio *chip,
260 				   struct audioformat *fmt,
261 				   struct usb_host_interface *alts)
262 {
263 	if ((fmt->ep_attr & USB_ENDPOINT_SYNCTYPE) != USB_ENDPOINT_SYNC_ASYNC)
264 		return 0;
265 
266 	if (__add_generic_implicit_fb(chip, fmt,
267 				      alts->desc.bInterfaceNumber + 1,
268 				      alts->desc.bAlternateSetting))
269 		return 1;
270 	return __add_generic_implicit_fb(chip, fmt,
271 					 alts->desc.bInterfaceNumber - 1,
272 					 alts->desc.bAlternateSetting);
273 }
274 
275 static const struct snd_usb_implicit_fb_match *
find_implicit_fb_entry(struct snd_usb_audio * chip,const struct snd_usb_implicit_fb_match * match,const struct usb_host_interface * alts)276 find_implicit_fb_entry(struct snd_usb_audio *chip,
277 		       const struct snd_usb_implicit_fb_match *match,
278 		       const struct usb_host_interface *alts)
279 {
280 	for (; match->id; match++)
281 		if (match->id == chip->usb_id &&
282 		    (!match->iface_class ||
283 		     (alts->desc.bInterfaceClass == match->iface_class)))
284 			return match;
285 
286 	return NULL;
287 }
288 
289 /* Setup an implicit feedback endpoint from a quirk. Returns 0 if no quirk
290  * applies. Returns 1 if a quirk was found.
291  */
audioformat_implicit_fb_quirk(struct snd_usb_audio * chip,struct audioformat * fmt,struct usb_host_interface * alts)292 static int audioformat_implicit_fb_quirk(struct snd_usb_audio *chip,
293 					 struct audioformat *fmt,
294 					 struct usb_host_interface *alts)
295 {
296 	const struct snd_usb_implicit_fb_match *p;
297 	unsigned int attr = fmt->ep_attr & USB_ENDPOINT_SYNCTYPE;
298 
299 	p = find_implicit_fb_entry(chip, playback_implicit_fb_quirks, alts);
300 	if (p) {
301 		switch (p->type) {
302 		case IMPLICIT_FB_GENERIC:
303 			return add_generic_implicit_fb(chip, fmt, alts);
304 		case IMPLICIT_FB_NONE:
305 			return 0; /* No quirk */
306 		case IMPLICIT_FB_FIXED:
307 			return add_implicit_fb_sync_ep(chip, fmt, p->ep_num, 0,
308 						       p->iface, NULL);
309 		}
310 	}
311 
312 	/* Special handling for devices with capture quirks */
313 	p = find_implicit_fb_entry(chip, capture_implicit_fb_quirks, alts);
314 	if (p) {
315 		switch (p->type) {
316 		case IMPLICIT_FB_FIXED:
317 			return 0; /* no quirk */
318 		case IMPLICIT_FB_BOTH:
319 			chip->quirk_flags |= QUIRK_FLAG_PLAYBACK_FIRST;
320 			return add_generic_implicit_fb(chip, fmt, alts);
321 		}
322 	}
323 
324 	/* Generic UAC2 implicit feedback */
325 	if (attr == USB_ENDPOINT_SYNC_ASYNC &&
326 	    alts->desc.bInterfaceClass == USB_CLASS_AUDIO &&
327 	    alts->desc.bInterfaceProtocol == UAC_VERSION_2 &&
328 	    alts->desc.bNumEndpoints == 1) {
329 		if (add_generic_uac2_implicit_fb(chip, fmt,
330 						 alts->desc.bInterfaceNumber + 1,
331 						 alts->desc.bAlternateSetting))
332 			return 1;
333 	}
334 
335 	/* Roland/BOSS implicit feedback with vendor spec class */
336 	if (USB_ID_VENDOR(chip->usb_id) == 0x0582) {
337 		if (add_roland_implicit_fb(chip, fmt, alts) > 0)
338 			return 1;
339 	}
340 
341 	/* Pioneer devices with vendor spec class */
342 	if (is_pioneer_implicit_fb(chip, alts)) {
343 		chip->quirk_flags |= QUIRK_FLAG_PLAYBACK_FIRST;
344 		return add_implicit_fb_sync_ep(chip, fmt,
345 					       get_endpoint(alts, 1)->bEndpointAddress,
346 					       1, alts->desc.bInterfaceNumber,
347 					       alts);
348 	}
349 
350 	/* Try the generic implicit fb if available */
351 	if (chip->generic_implicit_fb ||
352 	    (chip->quirk_flags & QUIRK_FLAG_GENERIC_IMPLICIT_FB))
353 		return add_generic_implicit_fb(chip, fmt, alts);
354 
355 	/* No quirk */
356 	return 0;
357 }
358 
359 /* same for capture, but only handling FIXED entry */
audioformat_capture_quirk(struct snd_usb_audio * chip,struct audioformat * fmt,struct usb_host_interface * alts)360 static int audioformat_capture_quirk(struct snd_usb_audio *chip,
361 				     struct audioformat *fmt,
362 				     struct usb_host_interface *alts)
363 {
364 	const struct snd_usb_implicit_fb_match *p;
365 
366 	p = find_implicit_fb_entry(chip, capture_implicit_fb_quirks, alts);
367 	if (p && (p->type == IMPLICIT_FB_FIXED || p->type == IMPLICIT_FB_BOTH))
368 		return add_implicit_fb_sync_ep(chip, fmt, p->ep_num, 0,
369 					       p->iface, NULL);
370 
371 	/* Roland/BOSS need full-duplex streams */
372 	if (USB_ID_VENDOR(chip->usb_id) == 0x0582) {
373 		if (add_roland_capture_quirk(chip, fmt, alts) > 0)
374 			return 1;
375 	}
376 
377 	if (is_pioneer_implicit_fb(chip, alts))
378 		return 1; /* skip the quirk, also don't handle generic sync EP */
379 	return 0;
380 }
381 
382 /*
383  * Parse altset and set up implicit feedback endpoint on the audioformat
384  */
snd_usb_parse_implicit_fb_quirk(struct snd_usb_audio * chip,struct audioformat * fmt,struct usb_host_interface * alts)385 int snd_usb_parse_implicit_fb_quirk(struct snd_usb_audio *chip,
386 				    struct audioformat *fmt,
387 				    struct usb_host_interface *alts)
388 {
389 	if (chip->quirk_flags & QUIRK_FLAG_SKIP_IMPLICIT_FB)
390 		return 0;
391 	if (fmt->endpoint & USB_DIR_IN)
392 		return audioformat_capture_quirk(chip, fmt, alts);
393 	else
394 		return audioformat_implicit_fb_quirk(chip, fmt, alts);
395 }
396 
397 /*
398  * Return the score of matching two audioformats.
399  * Veto the audioformat if:
400  * - It has no channels for some reason.
401  * - Requested PCM format is not supported.
402  * - Requested sample rate is not supported.
403  */
match_endpoint_audioformats(struct snd_usb_substream * subs,const struct audioformat * fp,int rate,int channels,snd_pcm_format_t pcm_format)404 static int match_endpoint_audioformats(struct snd_usb_substream *subs,
405 				       const struct audioformat *fp,
406 				       int rate, int channels,
407 				       snd_pcm_format_t pcm_format)
408 {
409 	int i, score;
410 
411 	if (fp->channels < 1)
412 		return 0;
413 
414 	if (!(fp->formats & pcm_format_to_bits(pcm_format)))
415 		return 0;
416 
417 	if (fp->rates & SNDRV_PCM_RATE_CONTINUOUS) {
418 		if (rate < fp->rate_min || rate > fp->rate_max)
419 			return 0;
420 	} else {
421 		for (i = 0; i < fp->nr_rates; i++) {
422 			if (fp->rate_table[i] == rate)
423 				break;
424 		}
425 		if (i >= fp->nr_rates)
426 			return 0;
427 	}
428 
429 	score = 1;
430 	if (fp->channels == channels)
431 		score++;
432 
433 	return score;
434 }
435 
436 static struct snd_usb_substream *
find_matching_substream(struct snd_usb_audio * chip,int stream,int ep_num,int fmt_type)437 find_matching_substream(struct snd_usb_audio *chip, int stream, int ep_num,
438 			int fmt_type)
439 {
440 	struct snd_usb_stream *as;
441 	struct snd_usb_substream *subs;
442 
443 	list_for_each_entry(as, &chip->pcm_list, list) {
444 		subs = &as->substream[stream];
445 		if (as->fmt_type == fmt_type && subs->ep_num == ep_num)
446 			return subs;
447 	}
448 
449 	return NULL;
450 }
451 
452 /*
453  * Return the audioformat that is suitable for the implicit fb
454  */
455 const struct audioformat *
snd_usb_find_implicit_fb_sync_format(struct snd_usb_audio * chip,const struct audioformat * target,const struct snd_pcm_hw_params * params,int stream,bool * fixed_rate)456 snd_usb_find_implicit_fb_sync_format(struct snd_usb_audio *chip,
457 				     const struct audioformat *target,
458 				     const struct snd_pcm_hw_params *params,
459 				     int stream,
460 				     bool *fixed_rate)
461 {
462 	struct snd_usb_substream *subs;
463 	const struct audioformat *fp, *sync_fmt = NULL;
464 	int score, high_score;
465 
466 	/* Use the original audioformat as fallback for the shared altset */
467 	if (target->iface == target->sync_iface &&
468 	    target->altsetting == target->sync_altsetting)
469 		sync_fmt = target;
470 
471 	subs = find_matching_substream(chip, stream, target->sync_ep,
472 				       target->fmt_type);
473 	if (!subs)
474 		goto end;
475 
476 	high_score = 0;
477 	list_for_each_entry(fp, &subs->fmt_list, list) {
478 		score = match_endpoint_audioformats(subs, fp,
479 						    params_rate(params),
480 						    params_channels(params),
481 						    params_format(params));
482 		if (score > high_score) {
483 			sync_fmt = fp;
484 			high_score = score;
485 		}
486 	}
487 
488  end:
489 	if (fixed_rate)
490 		*fixed_rate = snd_usb_pcm_has_fixed_rate(subs);
491 	return sync_fmt;
492 }
493 
494