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 } 311 312