static bool uac_clock_source_is_valid(struct snd_usb_audio *chip, int source_id)
{
int err;
unsigned char data;
struct usb_device *dev = chip->dev;
struct uac_clock_source_descriptor *cs_desc =
snd_usb_find_clock_source(chip->ctrl_intf, source_id);
if (!cs_desc)
return 0;
/* If a clock source can't tell us whether it's valid, we assume it is */
if (!uac2_control_is_readable(cs_desc->bmControls, UAC2_CS_CONTROL_CLOCK_VALID))
return 1;
err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
UAC2_CS_CONTROL_CLOCK_VALID << 8,
snd_usb_ctrl_intf(chip) | (source_id << 8),
&data, sizeof(data), 1000);
if (err < 0) {
snd_printk(KERN_WARNING "%s(): cannot get clock validity for id %d\n",
__func__, source_id);
return 0;
}
return !!data;
}
static int __uac_clock_find_source(struct snd_usb_audio *chip,
int entity_id, unsigned long *visited)
{
struct uac_clock_source_descriptor *source;
struct uac_clock_selector_descriptor *selector;
struct uac_clock_multiplier_descriptor *multiplier;
entity_id &= 0xff;
if (test_and_set_bit(entity_id, visited)) {
#ifdef CONFIG_DEBUG_PRINTK
snd_printk(KERN_WARNING
"%s(): recursive clock topology detected, id %d.\n",
__func__, entity_id);
#else
;
#endif
return -EINVAL;
}
/* first, see if the ID we're looking for is a clock source already */
source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id);
if (source)
return source->bClockID;
selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
if (selector) {
int ret;
/* the entity ID we are looking for is a selector.
* find out what it currently selects */
ret = uac_clock_selector_get_val(chip, selector->bClockID);
if (ret < 0)
return ret;
/* Selector values are one-based */
if (ret > selector->bNrInPins || ret < 1) {
printk(KERN_ERR
"%s(): selector reported illegal value, id %d, ret %d\n",
__func__, selector->bClockID, ret);
return -EINVAL;
}
return __uac_clock_find_source(chip, selector->baCSourceID[ret-1],
visited);
}
/* FIXME: multipliers only act as pass-thru element for now */
multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id);
if (multiplier)
return __uac_clock_find_source(chip, multiplier->bCSourceID,
visited);
return -EINVAL;
}
static int __uac_clock_find_source(struct snd_usb_audio *chip,
int entity_id, unsigned long *visited)
{
struct uac_clock_source_descriptor *source;
struct uac_clock_selector_descriptor *selector;
struct uac_clock_multiplier_descriptor *multiplier;
entity_id &= 0xff;
if (test_and_set_bit(entity_id, visited)) {
snd_printk(KERN_WARNING
"%s(): recursive clock topology detected, id %d.\n",
__func__, entity_id);
return -EINVAL;
}
source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id);
if (source)
return source->bClockID;
selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
if (selector) {
int ret;
ret = uac_clock_selector_get_val(chip, selector->bClockID);
if (ret < 0)
return ret;
if (ret > selector->bNrInPins || ret < 1) {
printk(KERN_ERR
"%s(): selector reported illegal value, id %d, ret %d\n",
__func__, selector->bClockID, ret);
return -EINVAL;
}
return __uac_clock_find_source(chip, selector->baCSourceID[ret-1],
visited);
}
multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id);
if (multiplier)
return __uac_clock_find_source(chip, multiplier->bCSourceID,
visited);
return -EINVAL;
}
static bool uac_clock_source_is_valid(struct snd_usb_audio *chip,
int protocol,
int source_id)
{
int err;
unsigned char data;
struct usb_device *dev = chip->dev;
u32 bmControls;
if (protocol == UAC_VERSION_3) {
struct uac3_clock_source_descriptor *cs_desc =
snd_usb_find_clock_source_v3(chip->ctrl_intf, source_id);
if (!cs_desc)
return 0;
bmControls = le32_to_cpu(cs_desc->bmControls);
} else { /* UAC_VERSION_1/2 */
struct uac_clock_source_descriptor *cs_desc =
snd_usb_find_clock_source(chip->ctrl_intf, source_id);
if (!cs_desc)
return 0;
bmControls = cs_desc->bmControls;
}
/* If a clock source can't tell us whether it's valid, we assume it is */
if (!uac_v2v3_control_is_readable(bmControls,
UAC2_CS_CONTROL_CLOCK_VALID))
return 1;
err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
UAC2_CS_CONTROL_CLOCK_VALID << 8,
snd_usb_ctrl_intf(chip) | (source_id << 8),
&data, sizeof(data));
if (err < 0) {
dev_warn(&dev->dev,
"%s(): cannot get clock validity for id %d\n",
__func__, source_id);
return 0;
}
return !!data;
}
static int set_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
struct usb_host_interface *alts,
struct audioformat *fmt, int rate)
{
struct usb_device *dev = chip->dev;
__le32 data;
int err, cur_rate, prev_rate;
int clock;
bool writeable;
u32 bmControls;
/* First, try to find a valid clock. This may trigger
* automatic clock selection if the current clock is not
* valid.
*/
clock = snd_usb_clock_find_source(chip, fmt->protocol,
fmt->clock, true);
if (clock < 0) {
/* We did not find a valid clock, but that might be
* because the current sample rate does not match an
* external clock source. Try again without validation
* and we will do another validation after setting the
* rate.
*/
clock = snd_usb_clock_find_source(chip, fmt->protocol,
fmt->clock, false);
if (clock < 0)
return clock;
}
prev_rate = get_sample_rate_v2v3(chip, iface, fmt->altsetting, clock);
if (prev_rate == rate)
goto validation;
if (fmt->protocol == UAC_VERSION_3) {
struct uac3_clock_source_descriptor *cs_desc;
cs_desc = snd_usb_find_clock_source_v3(chip->ctrl_intf, clock);
bmControls = le32_to_cpu(cs_desc->bmControls);
} else {
struct uac_clock_source_descriptor *cs_desc;
cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, clock);
bmControls = cs_desc->bmControls;
}
writeable = uac_v2v3_control_is_writeable(bmControls,
UAC2_CS_CONTROL_SAM_FREQ);
if (writeable) {
data = cpu_to_le32(rate);
err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
UAC2_CS_CONTROL_SAM_FREQ << 8,
snd_usb_ctrl_intf(chip) | (clock << 8),
&data, sizeof(data));
if (err < 0) {
usb_audio_err(chip,
"%d:%d: cannot set freq %d (v2/v3): err %d\n",
iface, fmt->altsetting, rate, err);
return err;
}
cur_rate = get_sample_rate_v2v3(chip, iface,
fmt->altsetting, clock);
} else {
cur_rate = prev_rate;
}
if (cur_rate != rate) {
if (!writeable) {
usb_audio_warn(chip,
"%d:%d: freq mismatch (RO clock): req %d, clock runs @%d\n",
iface, fmt->altsetting, rate, cur_rate);
return -ENXIO;
}
usb_audio_dbg(chip,
"current rate %d is different from the runtime rate %d\n",
cur_rate, rate);
}
/* Some devices doesn't respond to sample rate changes while the
* interface is active. */
if (rate != prev_rate) {
usb_set_interface(dev, iface, 0);
snd_usb_set_interface_quirk(dev);
usb_set_interface(dev, iface, fmt->altsetting);
snd_usb_set_interface_quirk(dev);
}
validation:
/* validate clock after rate change */
if (!uac_clock_source_is_valid(chip, fmt->protocol, clock))
return -ENXIO;
return 0;
}
static int __uac_clock_find_source(struct snd_usb_audio *chip, int entity_id,
unsigned long *visited, bool validate)
{
struct uac_clock_source_descriptor *source;
struct uac_clock_selector_descriptor *selector;
struct uac_clock_multiplier_descriptor *multiplier;
entity_id &= 0xff;
if (test_and_set_bit(entity_id, visited)) {
usb_audio_warn(chip,
"%s(): recursive clock topology detected, id %d.\n",
__func__, entity_id);
return -EINVAL;
}
/* first, see if the ID we're looking for is a clock source already */
source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id);
if (source) {
entity_id = source->bClockID;
if (validate && !uac_clock_source_is_valid(chip, UAC_VERSION_2,
entity_id)) {
usb_audio_err(chip,
"clock source %d is not valid, cannot use\n",
entity_id);
return -ENXIO;
}
return entity_id;
}
selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
if (selector) {
int ret, i, cur;
/* the entity ID we are looking for is a selector.
* find out what it currently selects */
ret = uac_clock_selector_get_val(chip, selector->bClockID);
if (ret < 0)
return ret;
/* Selector values are one-based */
if (ret > selector->bNrInPins || ret < 1) {
usb_audio_err(chip,
"%s(): selector reported illegal value, id %d, ret %d\n",
__func__, selector->bClockID, ret);
return -EINVAL;
}
cur = ret;
ret = __uac_clock_find_source(chip, selector->baCSourceID[ret - 1],
visited, validate);
if (!validate || ret > 0 || !chip->autoclock)
return ret;
/* The current clock source is invalid, try others. */
for (i = 1; i <= selector->bNrInPins; i++) {
int err;
if (i == cur)
continue;
ret = __uac_clock_find_source(chip, selector->baCSourceID[i - 1],
visited, true);
if (ret < 0)
continue;
err = uac_clock_selector_set_val(chip, entity_id, i);
if (err < 0)
continue;
usb_audio_info(chip,
"found and selected valid clock source %d\n",
ret);
return ret;
}
return -ENXIO;
}
/* FIXME: multipliers only act as pass-thru element for now */
multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id);
if (multiplier)
return __uac_clock_find_source(chip, multiplier->bCSourceID,
visited, validate);
return -EINVAL;
}
