Loading...
1/*
2 * Clock domain and sample rate management functions
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17 *
18 */
19
20#include <linux/bitops.h>
21#include <linux/init.h>
22#include <linux/string.h>
23#include <linux/usb.h>
24#include <linux/usb/audio.h>
25#include <linux/usb/audio-v2.h>
26
27#include <sound/core.h>
28#include <sound/info.h>
29#include <sound/pcm.h>
30
31#include "usbaudio.h"
32#include "card.h"
33#include "helper.h"
34#include "clock.h"
35#include "quirks.h"
36
37static struct uac_clock_source_descriptor *
38 snd_usb_find_clock_source(struct usb_host_interface *ctrl_iface,
39 int clock_id)
40{
41 struct uac_clock_source_descriptor *cs = NULL;
42
43 while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
44 ctrl_iface->extralen,
45 cs, UAC2_CLOCK_SOURCE))) {
46 if (cs->bClockID == clock_id)
47 return cs;
48 }
49
50 return NULL;
51}
52
53static struct uac_clock_selector_descriptor *
54 snd_usb_find_clock_selector(struct usb_host_interface *ctrl_iface,
55 int clock_id)
56{
57 struct uac_clock_selector_descriptor *cs = NULL;
58
59 while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
60 ctrl_iface->extralen,
61 cs, UAC2_CLOCK_SELECTOR))) {
62 if (cs->bClockID == clock_id)
63 return cs;
64 }
65
66 return NULL;
67}
68
69static struct uac_clock_multiplier_descriptor *
70 snd_usb_find_clock_multiplier(struct usb_host_interface *ctrl_iface,
71 int clock_id)
72{
73 struct uac_clock_multiplier_descriptor *cs = NULL;
74
75 while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
76 ctrl_iface->extralen,
77 cs, UAC2_CLOCK_MULTIPLIER))) {
78 if (cs->bClockID == clock_id)
79 return cs;
80 }
81
82 return NULL;
83}
84
85static int uac_clock_selector_get_val(struct snd_usb_audio *chip, int selector_id)
86{
87 unsigned char buf;
88 int ret;
89
90 ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
91 UAC2_CS_CUR,
92 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
93 UAC2_CX_CLOCK_SELECTOR << 8,
94 snd_usb_ctrl_intf(chip) | (selector_id << 8),
95 &buf, sizeof(buf));
96
97 if (ret < 0)
98 return ret;
99
100 return buf;
101}
102
103static int uac_clock_selector_set_val(struct snd_usb_audio *chip, int selector_id,
104 unsigned char pin)
105{
106 int ret;
107
108 ret = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0),
109 UAC2_CS_CUR,
110 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
111 UAC2_CX_CLOCK_SELECTOR << 8,
112 snd_usb_ctrl_intf(chip) | (selector_id << 8),
113 &pin, sizeof(pin));
114 if (ret < 0)
115 return ret;
116
117 if (ret != sizeof(pin)) {
118 usb_audio_err(chip,
119 "setting selector (id %d) unexpected length %d\n",
120 selector_id, ret);
121 return -EINVAL;
122 }
123
124 ret = uac_clock_selector_get_val(chip, selector_id);
125 if (ret < 0)
126 return ret;
127
128 if (ret != pin) {
129 usb_audio_err(chip,
130 "setting selector (id %d) to %x failed (current: %d)\n",
131 selector_id, pin, ret);
132 return -EINVAL;
133 }
134
135 return ret;
136}
137
138static bool uac_clock_source_is_valid(struct snd_usb_audio *chip, int source_id)
139{
140 int err;
141 unsigned char data;
142 struct usb_device *dev = chip->dev;
143 struct uac_clock_source_descriptor *cs_desc =
144 snd_usb_find_clock_source(chip->ctrl_intf, source_id);
145
146 if (!cs_desc)
147 return 0;
148
149 /* If a clock source can't tell us whether it's valid, we assume it is */
150 if (!uac2_control_is_readable(cs_desc->bmControls,
151 UAC2_CS_CONTROL_CLOCK_VALID - 1))
152 return 1;
153
154 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
155 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
156 UAC2_CS_CONTROL_CLOCK_VALID << 8,
157 snd_usb_ctrl_intf(chip) | (source_id << 8),
158 &data, sizeof(data));
159
160 if (err < 0) {
161 dev_warn(&dev->dev,
162 "%s(): cannot get clock validity for id %d\n",
163 __func__, source_id);
164 return 0;
165 }
166
167 return !!data;
168}
169
170static int __uac_clock_find_source(struct snd_usb_audio *chip,
171 int entity_id, unsigned long *visited,
172 bool validate)
173{
174 struct uac_clock_source_descriptor *source;
175 struct uac_clock_selector_descriptor *selector;
176 struct uac_clock_multiplier_descriptor *multiplier;
177
178 entity_id &= 0xff;
179
180 if (test_and_set_bit(entity_id, visited)) {
181 usb_audio_warn(chip,
182 "%s(): recursive clock topology detected, id %d.\n",
183 __func__, entity_id);
184 return -EINVAL;
185 }
186
187 /* first, see if the ID we're looking for is a clock source already */
188 source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id);
189 if (source) {
190 entity_id = source->bClockID;
191 if (validate && !uac_clock_source_is_valid(chip, entity_id)) {
192 usb_audio_err(chip,
193 "clock source %d is not valid, cannot use\n",
194 entity_id);
195 return -ENXIO;
196 }
197 return entity_id;
198 }
199
200 selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
201 if (selector) {
202 int ret, i, cur;
203
204 /* the entity ID we are looking for is a selector.
205 * find out what it currently selects */
206 ret = uac_clock_selector_get_val(chip, selector->bClockID);
207 if (ret < 0)
208 return ret;
209
210 /* Selector values are one-based */
211
212 if (ret > selector->bNrInPins || ret < 1) {
213 usb_audio_err(chip,
214 "%s(): selector reported illegal value, id %d, ret %d\n",
215 __func__, selector->bClockID, ret);
216
217 return -EINVAL;
218 }
219
220 cur = ret;
221 ret = __uac_clock_find_source(chip, selector->baCSourceID[ret - 1],
222 visited, validate);
223 if (!validate || ret > 0 || !chip->autoclock)
224 return ret;
225
226 /* The current clock source is invalid, try others. */
227 for (i = 1; i <= selector->bNrInPins; i++) {
228 int err;
229
230 if (i == cur)
231 continue;
232
233 ret = __uac_clock_find_source(chip, selector->baCSourceID[i - 1],
234 visited, true);
235 if (ret < 0)
236 continue;
237
238 err = uac_clock_selector_set_val(chip, entity_id, i);
239 if (err < 0)
240 continue;
241
242 usb_audio_info(chip,
243 "found and selected valid clock source %d\n",
244 ret);
245 return ret;
246 }
247
248 return -ENXIO;
249 }
250
251 /* FIXME: multipliers only act as pass-thru element for now */
252 multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id);
253 if (multiplier)
254 return __uac_clock_find_source(chip, multiplier->bCSourceID,
255 visited, validate);
256
257 return -EINVAL;
258}
259
260/*
261 * For all kinds of sample rate settings and other device queries,
262 * the clock source (end-leaf) must be used. However, clock selectors,
263 * clock multipliers and sample rate converters may be specified as
264 * clock source input to terminal. This functions walks the clock path
265 * to its end and tries to find the source.
266 *
267 * The 'visited' bitfield is used internally to detect recursive loops.
268 *
269 * Returns the clock source UnitID (>=0) on success, or an error.
270 */
271int snd_usb_clock_find_source(struct snd_usb_audio *chip, int entity_id,
272 bool validate)
273{
274 DECLARE_BITMAP(visited, 256);
275 memset(visited, 0, sizeof(visited));
276 return __uac_clock_find_source(chip, entity_id, visited, validate);
277}
278
279static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface,
280 struct usb_host_interface *alts,
281 struct audioformat *fmt, int rate)
282{
283 struct usb_device *dev = chip->dev;
284 unsigned int ep;
285 unsigned char data[3];
286 int err, crate;
287
288 ep = get_endpoint(alts, 0)->bEndpointAddress;
289
290 /* if endpoint doesn't have sampling rate control, bail out */
291 if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
292 return 0;
293
294 data[0] = rate;
295 data[1] = rate >> 8;
296 data[2] = rate >> 16;
297 if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
298 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
299 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
300 data, sizeof(data))) < 0) {
301 dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
302 iface, fmt->altsetting, rate, ep);
303 return err;
304 }
305
306 if ((err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
307 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
308 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
309 data, sizeof(data))) < 0) {
310 dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
311 iface, fmt->altsetting, ep);
312 return 0; /* some devices don't support reading */
313 }
314
315 crate = data[0] | (data[1] << 8) | (data[2] << 16);
316 if (crate != rate) {
317 dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
318 // runtime->rate = crate;
319 }
320
321 return 0;
322}
323
324static int get_sample_rate_v2(struct snd_usb_audio *chip, int iface,
325 int altsetting, int clock)
326{
327 struct usb_device *dev = chip->dev;
328 __le32 data;
329 int err;
330
331 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
332 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
333 UAC2_CS_CONTROL_SAM_FREQ << 8,
334 snd_usb_ctrl_intf(chip) | (clock << 8),
335 &data, sizeof(data));
336 if (err < 0) {
337 dev_warn(&dev->dev, "%d:%d: cannot get freq (v2): err %d\n",
338 iface, altsetting, err);
339 return 0;
340 }
341
342 return le32_to_cpu(data);
343}
344
345static int set_sample_rate_v2(struct snd_usb_audio *chip, int iface,
346 struct usb_host_interface *alts,
347 struct audioformat *fmt, int rate)
348{
349 struct usb_device *dev = chip->dev;
350 __le32 data;
351 int err, cur_rate, prev_rate;
352 int clock;
353 bool writeable;
354 struct uac_clock_source_descriptor *cs_desc;
355
356 clock = snd_usb_clock_find_source(chip, fmt->clock, true);
357 if (clock < 0)
358 return clock;
359
360 prev_rate = get_sample_rate_v2(chip, iface, fmt->altsetting, clock);
361 if (prev_rate == rate)
362 return 0;
363
364 cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, clock);
365 writeable = uac2_control_is_writeable(cs_desc->bmControls, UAC2_CS_CONTROL_SAM_FREQ - 1);
366 if (writeable) {
367 data = cpu_to_le32(rate);
368 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
369 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
370 UAC2_CS_CONTROL_SAM_FREQ << 8,
371 snd_usb_ctrl_intf(chip) | (clock << 8),
372 &data, sizeof(data));
373 if (err < 0) {
374 usb_audio_err(chip,
375 "%d:%d: cannot set freq %d (v2): err %d\n",
376 iface, fmt->altsetting, rate, err);
377 return err;
378 }
379
380 cur_rate = get_sample_rate_v2(chip, iface, fmt->altsetting, clock);
381 } else {
382 cur_rate = prev_rate;
383 }
384
385 if (cur_rate != rate) {
386 if (!writeable) {
387 usb_audio_warn(chip,
388 "%d:%d: freq mismatch (RO clock): req %d, clock runs @%d\n",
389 iface, fmt->altsetting, rate, cur_rate);
390 return -ENXIO;
391 }
392 usb_audio_dbg(chip,
393 "current rate %d is different from the runtime rate %d\n",
394 cur_rate, rate);
395 }
396
397 /* Some devices doesn't respond to sample rate changes while the
398 * interface is active. */
399 if (rate != prev_rate) {
400 usb_set_interface(dev, iface, 0);
401 snd_usb_set_interface_quirk(dev);
402 usb_set_interface(dev, iface, fmt->altsetting);
403 snd_usb_set_interface_quirk(dev);
404 }
405
406 return 0;
407}
408
409int snd_usb_init_sample_rate(struct snd_usb_audio *chip, int iface,
410 struct usb_host_interface *alts,
411 struct audioformat *fmt, int rate)
412{
413 switch (fmt->protocol) {
414 case UAC_VERSION_1:
415 default:
416 return set_sample_rate_v1(chip, iface, alts, fmt, rate);
417
418 case UAC_VERSION_2:
419 return set_sample_rate_v2(chip, iface, alts, fmt, rate);
420 }
421}
422
1/*
2 * Clock domain and sample rate management functions
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17 *
18 */
19
20#include <linux/bitops.h>
21#include <linux/init.h>
22#include <linux/string.h>
23#include <linux/usb.h>
24#include <linux/usb/audio.h>
25#include <linux/usb/audio-v2.h>
26
27#include <sound/core.h>
28#include <sound/info.h>
29#include <sound/pcm.h>
30
31#include "usbaudio.h"
32#include "card.h"
33#include "helper.h"
34#include "clock.h"
35#include "quirks.h"
36
37static struct uac_clock_source_descriptor *
38 snd_usb_find_clock_source(struct usb_host_interface *ctrl_iface,
39 int clock_id)
40{
41 struct uac_clock_source_descriptor *cs = NULL;
42
43 while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
44 ctrl_iface->extralen,
45 cs, UAC2_CLOCK_SOURCE))) {
46 if (cs->bClockID == clock_id)
47 return cs;
48 }
49
50 return NULL;
51}
52
53static struct uac_clock_selector_descriptor *
54 snd_usb_find_clock_selector(struct usb_host_interface *ctrl_iface,
55 int clock_id)
56{
57 struct uac_clock_selector_descriptor *cs = NULL;
58
59 while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
60 ctrl_iface->extralen,
61 cs, UAC2_CLOCK_SELECTOR))) {
62 if (cs->bClockID == clock_id)
63 return cs;
64 }
65
66 return NULL;
67}
68
69static struct uac_clock_multiplier_descriptor *
70 snd_usb_find_clock_multiplier(struct usb_host_interface *ctrl_iface,
71 int clock_id)
72{
73 struct uac_clock_multiplier_descriptor *cs = NULL;
74
75 while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
76 ctrl_iface->extralen,
77 cs, UAC2_CLOCK_MULTIPLIER))) {
78 if (cs->bClockID == clock_id)
79 return cs;
80 }
81
82 return NULL;
83}
84
85static int uac_clock_selector_get_val(struct snd_usb_audio *chip, int selector_id)
86{
87 unsigned char buf;
88 int ret;
89
90 ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
91 UAC2_CS_CUR,
92 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
93 UAC2_CX_CLOCK_SELECTOR << 8,
94 snd_usb_ctrl_intf(chip) | (selector_id << 8),
95 &buf, sizeof(buf));
96
97 if (ret < 0)
98 return ret;
99
100 return buf;
101}
102
103static int uac_clock_selector_set_val(struct snd_usb_audio *chip, int selector_id,
104 unsigned char pin)
105{
106 int ret;
107
108 ret = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0),
109 UAC2_CS_CUR,
110 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
111 UAC2_CX_CLOCK_SELECTOR << 8,
112 snd_usb_ctrl_intf(chip) | (selector_id << 8),
113 &pin, sizeof(pin));
114 if (ret < 0)
115 return ret;
116
117 if (ret != sizeof(pin)) {
118 usb_audio_err(chip,
119 "setting selector (id %d) unexpected length %d\n",
120 selector_id, ret);
121 return -EINVAL;
122 }
123
124 ret = uac_clock_selector_get_val(chip, selector_id);
125 if (ret < 0)
126 return ret;
127
128 if (ret != pin) {
129 usb_audio_err(chip,
130 "setting selector (id %d) to %x failed (current: %d)\n",
131 selector_id, pin, ret);
132 return -EINVAL;
133 }
134
135 return ret;
136}
137
138static bool uac_clock_source_is_valid(struct snd_usb_audio *chip, int source_id)
139{
140 int err;
141 unsigned char data;
142 struct usb_device *dev = chip->dev;
143 struct uac_clock_source_descriptor *cs_desc =
144 snd_usb_find_clock_source(chip->ctrl_intf, source_id);
145
146 if (!cs_desc)
147 return 0;
148
149 /* If a clock source can't tell us whether it's valid, we assume it is */
150 if (!uac2_control_is_readable(cs_desc->bmControls,
151 UAC2_CS_CONTROL_CLOCK_VALID - 1))
152 return 1;
153
154 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
155 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
156 UAC2_CS_CONTROL_CLOCK_VALID << 8,
157 snd_usb_ctrl_intf(chip) | (source_id << 8),
158 &data, sizeof(data));
159
160 if (err < 0) {
161 dev_warn(&dev->dev,
162 "%s(): cannot get clock validity for id %d\n",
163 __func__, source_id);
164 return 0;
165 }
166
167 return !!data;
168}
169
170static int __uac_clock_find_source(struct snd_usb_audio *chip,
171 int entity_id, unsigned long *visited,
172 bool validate)
173{
174 struct uac_clock_source_descriptor *source;
175 struct uac_clock_selector_descriptor *selector;
176 struct uac_clock_multiplier_descriptor *multiplier;
177
178 entity_id &= 0xff;
179
180 if (test_and_set_bit(entity_id, visited)) {
181 usb_audio_warn(chip,
182 "%s(): recursive clock topology detected, id %d.\n",
183 __func__, entity_id);
184 return -EINVAL;
185 }
186
187 /* first, see if the ID we're looking for is a clock source already */
188 source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id);
189 if (source) {
190 entity_id = source->bClockID;
191 if (validate && !uac_clock_source_is_valid(chip, entity_id)) {
192 usb_audio_err(chip,
193 "clock source %d is not valid, cannot use\n",
194 entity_id);
195 return -ENXIO;
196 }
197 return entity_id;
198 }
199
200 selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
201 if (selector) {
202 int ret, i, cur;
203
204 /* the entity ID we are looking for is a selector.
205 * find out what it currently selects */
206 ret = uac_clock_selector_get_val(chip, selector->bClockID);
207 if (ret < 0)
208 return ret;
209
210 /* Selector values are one-based */
211
212 if (ret > selector->bNrInPins || ret < 1) {
213 usb_audio_err(chip,
214 "%s(): selector reported illegal value, id %d, ret %d\n",
215 __func__, selector->bClockID, ret);
216
217 return -EINVAL;
218 }
219
220 cur = ret;
221 ret = __uac_clock_find_source(chip, selector->baCSourceID[ret - 1],
222 visited, validate);
223 if (!validate || ret > 0 || !chip->autoclock)
224 return ret;
225
226 /* The current clock source is invalid, try others. */
227 for (i = 1; i <= selector->bNrInPins; i++) {
228 int err;
229
230 if (i == cur)
231 continue;
232
233 ret = __uac_clock_find_source(chip, selector->baCSourceID[i - 1],
234 visited, true);
235 if (ret < 0)
236 continue;
237
238 err = uac_clock_selector_set_val(chip, entity_id, i);
239 if (err < 0)
240 continue;
241
242 usb_audio_info(chip,
243 "found and selected valid clock source %d\n",
244 ret);
245 return ret;
246 }
247
248 return -ENXIO;
249 }
250
251 /* FIXME: multipliers only act as pass-thru element for now */
252 multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id);
253 if (multiplier)
254 return __uac_clock_find_source(chip, multiplier->bCSourceID,
255 visited, validate);
256
257 return -EINVAL;
258}
259
260/*
261 * For all kinds of sample rate settings and other device queries,
262 * the clock source (end-leaf) must be used. However, clock selectors,
263 * clock multipliers and sample rate converters may be specified as
264 * clock source input to terminal. This functions walks the clock path
265 * to its end and tries to find the source.
266 *
267 * The 'visited' bitfield is used internally to detect recursive loops.
268 *
269 * Returns the clock source UnitID (>=0) on success, or an error.
270 */
271int snd_usb_clock_find_source(struct snd_usb_audio *chip, int entity_id,
272 bool validate)
273{
274 DECLARE_BITMAP(visited, 256);
275 memset(visited, 0, sizeof(visited));
276 return __uac_clock_find_source(chip, entity_id, visited, validate);
277}
278
279static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface,
280 struct usb_host_interface *alts,
281 struct audioformat *fmt, int rate)
282{
283 struct usb_device *dev = chip->dev;
284 unsigned int ep;
285 unsigned char data[3];
286 int err, crate;
287
288 if (get_iface_desc(alts)->bNumEndpoints < 1)
289 return -EINVAL;
290 ep = get_endpoint(alts, 0)->bEndpointAddress;
291
292 /* if endpoint doesn't have sampling rate control, bail out */
293 if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
294 return 0;
295
296 data[0] = rate;
297 data[1] = rate >> 8;
298 data[2] = rate >> 16;
299 if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
300 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
301 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
302 data, sizeof(data))) < 0) {
303 dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
304 iface, fmt->altsetting, rate, ep);
305 return err;
306 }
307
308 /* Don't check the sample rate for devices which we know don't
309 * support reading */
310 if (snd_usb_get_sample_rate_quirk(chip))
311 return 0;
312 /* the firmware is likely buggy, don't repeat to fail too many times */
313 if (chip->sample_rate_read_error > 2)
314 return 0;
315
316 if ((err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
317 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
318 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
319 data, sizeof(data))) < 0) {
320 dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
321 iface, fmt->altsetting, ep);
322 chip->sample_rate_read_error++;
323 return 0; /* some devices don't support reading */
324 }
325
326 crate = data[0] | (data[1] << 8) | (data[2] << 16);
327 if (crate != rate) {
328 dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
329 // runtime->rate = crate;
330 }
331
332 return 0;
333}
334
335static int get_sample_rate_v2(struct snd_usb_audio *chip, int iface,
336 int altsetting, int clock)
337{
338 struct usb_device *dev = chip->dev;
339 __le32 data;
340 int err;
341
342 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
343 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
344 UAC2_CS_CONTROL_SAM_FREQ << 8,
345 snd_usb_ctrl_intf(chip) | (clock << 8),
346 &data, sizeof(data));
347 if (err < 0) {
348 dev_warn(&dev->dev, "%d:%d: cannot get freq (v2): err %d\n",
349 iface, altsetting, err);
350 return 0;
351 }
352
353 return le32_to_cpu(data);
354}
355
356static int set_sample_rate_v2(struct snd_usb_audio *chip, int iface,
357 struct usb_host_interface *alts,
358 struct audioformat *fmt, int rate)
359{
360 struct usb_device *dev = chip->dev;
361 __le32 data;
362 int err, cur_rate, prev_rate;
363 int clock;
364 bool writeable;
365 struct uac_clock_source_descriptor *cs_desc;
366
367 clock = snd_usb_clock_find_source(chip, fmt->clock, true);
368 if (clock < 0)
369 return clock;
370
371 prev_rate = get_sample_rate_v2(chip, iface, fmt->altsetting, clock);
372 if (prev_rate == rate)
373 return 0;
374
375 cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, clock);
376 writeable = uac2_control_is_writeable(cs_desc->bmControls, UAC2_CS_CONTROL_SAM_FREQ - 1);
377 if (writeable) {
378 data = cpu_to_le32(rate);
379 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
380 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
381 UAC2_CS_CONTROL_SAM_FREQ << 8,
382 snd_usb_ctrl_intf(chip) | (clock << 8),
383 &data, sizeof(data));
384 if (err < 0) {
385 usb_audio_err(chip,
386 "%d:%d: cannot set freq %d (v2): err %d\n",
387 iface, fmt->altsetting, rate, err);
388 return err;
389 }
390
391 cur_rate = get_sample_rate_v2(chip, iface, fmt->altsetting, clock);
392 } else {
393 cur_rate = prev_rate;
394 }
395
396 if (cur_rate != rate) {
397 if (!writeable) {
398 usb_audio_warn(chip,
399 "%d:%d: freq mismatch (RO clock): req %d, clock runs @%d\n",
400 iface, fmt->altsetting, rate, cur_rate);
401 return -ENXIO;
402 }
403 usb_audio_dbg(chip,
404 "current rate %d is different from the runtime rate %d\n",
405 cur_rate, rate);
406 }
407
408 /* Some devices doesn't respond to sample rate changes while the
409 * interface is active. */
410 if (rate != prev_rate) {
411 usb_set_interface(dev, iface, 0);
412 snd_usb_set_interface_quirk(dev);
413 usb_set_interface(dev, iface, fmt->altsetting);
414 snd_usb_set_interface_quirk(dev);
415 }
416
417 return 0;
418}
419
420int snd_usb_init_sample_rate(struct snd_usb_audio *chip, int iface,
421 struct usb_host_interface *alts,
422 struct audioformat *fmt, int rate)
423{
424 switch (fmt->protocol) {
425 case UAC_VERSION_1:
426 default:
427 return set_sample_rate_v1(chip, iface, alts, fmt, rate);
428
429 case UAC_VERSION_2:
430 return set_sample_rate_v2(chip, iface, alts, fmt, rate);
431 }
432}
433