ALSA: usb-audio: parse clock topology of UAC2 devices
[safe/jmp/linux-2.6] / sound / usb / clock.c
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/list.h>
23 #include <linux/slab.h>
24 #include <linux/string.h>
25 #include <linux/usb.h>
26 #include <linux/moduleparam.h>
27 #include <linux/mutex.h>
28 #include <linux/usb/audio.h>
29 #include <linux/usb/audio-v2.h>
30
31 #include <sound/core.h>
32 #include <sound/info.h>
33 #include <sound/pcm.h>
34 #include <sound/pcm_params.h>
35 #include <sound/initval.h>
36
37 #include "usbaudio.h"
38 #include "card.h"
39 #include "midi.h"
40 #include "mixer.h"
41 #include "proc.h"
42 #include "quirks.h"
43 #include "endpoint.h"
44 #include "helper.h"
45 #include "debug.h"
46 #include "pcm.h"
47 #include "urb.h"
48 #include "format.h"
49
50 static struct uac_clock_source_descriptor *
51         snd_usb_find_clock_source(struct usb_host_interface *ctrl_iface,
52                                   int clock_id)
53 {
54         struct uac_clock_source_descriptor *cs = NULL;
55
56         while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
57                                              ctrl_iface->extralen,
58                                              cs, UAC2_CLOCK_SOURCE))) {
59                 if (cs->bClockID == clock_id)
60                         return cs;
61         }
62
63         return NULL;
64 }
65
66 static struct uac_clock_selector_descriptor *
67         snd_usb_find_clock_selector(struct usb_host_interface *ctrl_iface,
68                                     int clock_id)
69 {
70         struct uac_clock_selector_descriptor *cs = NULL;
71
72         while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
73                                              ctrl_iface->extralen,
74                                              cs, UAC2_CLOCK_SELECTOR))) {
75                 if (cs->bClockID == clock_id)
76                         return cs;
77         }
78
79         return NULL;
80 }
81
82 static struct uac_clock_multiplier_descriptor *
83         snd_usb_find_clock_multiplier(struct usb_host_interface *ctrl_iface,
84                                       int clock_id)
85 {
86         struct uac_clock_multiplier_descriptor *cs = NULL;
87
88         while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
89                                              ctrl_iface->extralen,
90                                              cs, UAC2_CLOCK_MULTIPLIER))) {
91                 if (cs->bClockID == clock_id)
92                         return cs;
93         }
94
95         return NULL;
96 }
97
98 static int uac_clock_selector_get_val(struct snd_usb_audio *chip, int selector_id)
99 {
100         unsigned char buf;
101         int ret;
102
103         ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
104                               UAC2_CS_CUR,
105                               USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
106                               UAC2_CX_CLOCK_SELECTOR << 8, selector_id << 8,
107                               &buf, sizeof(buf), 1000);
108
109         if (ret < 0)
110                 return ret;
111
112         return buf;
113 }
114
115 static bool uac_clock_source_is_valid(struct snd_usb_audio *chip, int source_id)
116 {
117         int err;
118         unsigned char data;
119         struct usb_device *dev = chip->dev;
120
121         err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
122                               USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
123                               UAC2_CS_CONTROL_CLOCK_VALID << 8, source_id << 8,
124                               &data, sizeof(data), 1000);
125
126         if (err < 0) {
127                 snd_printk(KERN_WARNING "%s(): cannot get clock validity for id %d\n",
128                            __func__, source_id);
129                 return err;
130         }
131
132         return !!data;
133 }
134
135 /* Try to find the clock source ID of a given clock entity */
136
137 static int __uac_clock_find_source(struct snd_usb_audio *chip,
138                                    struct usb_host_interface *host_iface,
139                                    int entity_id, unsigned long *visited)
140 {
141         struct uac_clock_source_descriptor *source;
142         struct uac_clock_selector_descriptor *selector;
143         struct uac_clock_multiplier_descriptor *multiplier;
144
145         entity_id &= 0xff;
146
147         if (test_and_set_bit(entity_id, visited)) {
148                 snd_printk(KERN_WARNING
149                         "%s(): recursive clock topology detected, id %d.\n",
150                         __func__, entity_id);
151                 return -EINVAL;
152         }
153
154         /* first, see if the ID we're looking for is a clock source already */
155         source = snd_usb_find_clock_source(host_iface, entity_id);
156         if (source)
157                 return source->bClockID;
158
159         selector = snd_usb_find_clock_selector(host_iface, entity_id);
160         if (selector) {
161                 int ret;
162
163                 /* the entity ID we are looking for is a selector.
164                  * find out what it currently selects */
165                 ret = uac_clock_selector_get_val(chip, selector->bClockID);
166                 if (ret < 0)
167                         return ret;
168
169                 if (ret > selector->bNrInPins || ret < 1) {
170                         printk(KERN_ERR
171                                 "%s(): selector reported illegal value, id %d, ret %d\n",
172                                 __func__, selector->bClockID, ret);
173
174                         return -EINVAL;
175                 }
176
177                 return __uac_clock_find_source(chip, host_iface,
178                                                selector->baCSourceID[ret-1],
179                                                visited);
180         }
181
182         /* FIXME: multipliers only act as pass-thru element for now */
183         multiplier = snd_usb_find_clock_multiplier(host_iface, entity_id);
184         if (multiplier)
185                 return __uac_clock_find_source(chip, host_iface,
186                                                multiplier->bCSourceID, visited);
187
188         return -EINVAL;
189 }
190
191 int snd_usb_clock_find_source(struct snd_usb_audio *chip,
192                               struct usb_host_interface *host_iface,
193                               int entity_id)
194 {
195         DECLARE_BITMAP(visited, 256);
196         memset(visited, 0, sizeof(visited));
197         return __uac_clock_find_source(chip, host_iface, entity_id, visited);
198 }
199
200 static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface,
201                               struct usb_host_interface *alts,
202                               struct audioformat *fmt, int rate)
203 {
204         struct usb_device *dev = chip->dev;
205         unsigned int ep;
206         unsigned char data[3];
207         int err, crate;
208
209         ep = get_endpoint(alts, 0)->bEndpointAddress;
210
211         /* if endpoint doesn't have sampling rate control, bail out */
212         if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE)) {
213                 snd_printk(KERN_WARNING "%d:%d:%d: endpoint lacks sample rate attribute bit, cannot set.\n",
214                                    dev->devnum, iface, fmt->altsetting);
215                 return 0;
216         }
217
218         data[0] = rate;
219         data[1] = rate >> 8;
220         data[2] = rate >> 16;
221         if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
222                                    USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
223                                    UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
224                                    data, sizeof(data), 1000)) < 0) {
225                 snd_printk(KERN_ERR "%d:%d:%d: cannot set freq %d to ep %#x\n",
226                            dev->devnum, iface, fmt->altsetting, rate, ep);
227                 return err;
228         }
229
230         if ((err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
231                                    USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
232                                    UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
233                                    data, sizeof(data), 1000)) < 0) {
234                 snd_printk(KERN_WARNING "%d:%d:%d: cannot get freq at ep %#x\n",
235                            dev->devnum, iface, fmt->altsetting, ep);
236                 return 0; /* some devices don't support reading */
237         }
238
239         crate = data[0] | (data[1] << 8) | (data[2] << 16);
240         if (crate != rate) {
241                 snd_printd(KERN_WARNING "current rate %d is different from the runtime rate %d\n", crate, rate);
242                 // runtime->rate = crate;
243         }
244
245         return 0;
246 }
247
248 static int set_sample_rate_v2(struct snd_usb_audio *chip, int iface,
249                               struct usb_host_interface *alts,
250                               struct audioformat *fmt, int rate)
251 {
252         struct usb_device *dev = chip->dev;
253         unsigned char data[4];
254         int err, crate;
255         int clock = snd_usb_clock_find_source(chip, chip->ctrl_intf, fmt->clock);
256
257         if (clock < 0)
258                 return clock;
259
260         if (!uac_clock_source_is_valid(chip, clock)) {
261                 snd_printk(KERN_ERR "%d:%d:%d: clock source %d is not valid, cannot use\n",
262                            dev->devnum, iface, fmt->altsetting, clock);
263                 return -ENXIO;
264         }
265
266         data[0] = rate;
267         data[1] = rate >> 8;
268         data[2] = rate >> 16;
269         data[3] = rate >> 24;
270         if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
271                                    USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
272                                    UAC2_CS_CONTROL_SAM_FREQ << 8, clock << 8,
273                                    data, sizeof(data), 1000)) < 0) {
274                 snd_printk(KERN_ERR "%d:%d:%d: cannot set freq %d (v2)\n",
275                            dev->devnum, iface, fmt->altsetting, rate);
276                 return err;
277         }
278
279         if ((err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
280                                    USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
281                                    UAC2_CS_CONTROL_SAM_FREQ << 8, clock << 8,
282                                    data, sizeof(data), 1000)) < 0) {
283                 snd_printk(KERN_WARNING "%d:%d:%d: cannot get freq (v2)\n",
284                            dev->devnum, iface, fmt->altsetting);
285                 return err;
286         }
287
288         crate = data[0] | (data[1] << 8) | (data[2] << 16) | (data[3] << 24);
289         if (crate != rate)
290                 snd_printd(KERN_WARNING "current rate %d is different from the runtime rate %d\n", crate, rate);
291
292         return 0;
293 }
294
295 int snd_usb_init_sample_rate(struct snd_usb_audio *chip, int iface,
296                              struct usb_host_interface *alts,
297                              struct audioformat *fmt, int rate)
298 {
299         struct usb_interface_descriptor *altsd = get_iface_desc(alts);
300
301         switch (altsd->bInterfaceProtocol) {
302         case UAC_VERSION_1:
303                 return set_sample_rate_v1(chip, iface, alts, fmt, rate);
304
305         case UAC_VERSION_2:
306                 return set_sample_rate_v2(chip, iface, alts, fmt, rate);
307         }
308
309         return -EINVAL;
310 }
311