// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Clock domain and sample rate management functions
*/
#include <linux/bitops.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/usb.h>
#include <linux/usb/audio.h>
#include <linux/usb/audio-v2.h>
#include <linux/usb/audio-v3.h>
#include <sound/core.h>
#include <sound/info.h>
#include <sound/pcm.h>
#include "usbaudio.h"
#include "card.h"
#include "helper.h"
#include "clock.h"
#include "quirks.h"
union uac23_clock_source_desc {
struct uac_clock_source_descriptor v2;
struct uac3_clock_source_descriptor v3;
};
union uac23_clock_selector_desc {
struct uac_clock_selector_descriptor v2;
struct uac3_clock_selector_descriptor v3;
};
union uac23_clock_multiplier_desc {
struct uac_clock_multiplier_descriptor v2;
struct uac_clock_multiplier_descriptor v3;
};
#define GET_VAL(p, proto, field) \
((proto) == UAC_VERSION_3 ? (p)->v3.field : (p)->v2.field)
static void *find_uac_clock_desc(struct usb_host_interface *iface, int id,
bool (*validator)(void *, int, int),
u8 type, int proto)
{
void *cs = NULL;
while ((cs = snd_usb_find_csint_desc(iface->extra, iface->extralen,
cs, type))) {
if (validator(cs, id, proto))
return cs;
}
return NULL;
}
static bool validate_clock_source(void *p, int id, int proto)
{
union uac23_clock_source_desc *cs = p;
return GET_VAL(cs, proto, bClockID) == id;
}
static bool validate_clock_selector(void *p, int id, int proto)
{
union uac23_clock_selector_desc *cs = p;
return GET_VAL(cs, proto, bClockID) == id;
}
static bool validate_clock_multiplier(void *p, int id, int proto)
{
union uac23_clock_multiplier_desc *cs = p;
return GET_VAL(cs, proto, bClockID) == id;
}
#define DEFINE_FIND_HELPER(name, obj, validator, type2, type3) \
static obj *name(struct snd_usb_audio *chip, int id, \
const struct audioformat *fmt) \
{ \
struct usb_host_interface *ctrl_intf = \
snd_usb_find_ctrl_interface(chip, fmt->iface); \
return find_uac_clock_desc(ctrl_intf, id, validator, \
fmt->protocol == UAC_VERSION_3 ? (type3) : (type2), \
fmt->protocol); \
}
DEFINE_FIND_HELPER(snd_usb_find_clock_source,
union uac23_clock_source_desc, validate_clock_source,
UAC2_CLOCK_SOURCE, UAC3_CLOCK_SOURCE);
DEFINE_FIND_HELPER(snd_usb_find_clock_selector,
union uac23_clock_selector_desc, validate_clock_selector,
UAC2_CLOCK_SELECTOR, UAC3_CLOCK_SELECTOR);
DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier,
union uac23_clock_multiplier_desc, validate_clock_multiplier,
UAC2_CLOCK_MULTIPLIER, UAC3_CLOCK_MULTIPLIER);
static int uac_clock_selector_get_val(struct snd_usb_audio *chip,
int selector_id, int iface_no)
{
struct usb_host_interface *ctrl_intf;
unsigned char buf;
int ret;
ctrl_intf = snd_usb_find_ctrl_interface(chip, iface_no);
ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
UAC2_CS_CUR,
USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
UAC2_CX_CLOCK_SELECTOR << 8,
snd_usb_ctrl_intf(ctrl_intf) | (selector_id << 8),
&buf, sizeof(buf));
if (ret < 0)
return ret;
return buf;
}
static int uac_clock_selector_set_val(struct snd_usb_audio *chip,
int selector_id, unsigned char pin, int iface_no)
{
struct usb_host_interface *ctrl_intf;
int ret;
ctrl_intf = snd_usb_find_ctrl_interface(chip, iface_no);
ret = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0),
UAC2_CS_CUR,
USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
UAC2_CX_CLOCK_SELECTOR << 8,
snd_usb_ctrl_intf(ctrl_intf) | (selector_id << 8),
&pin, sizeof(pin));
if (ret < 0)
return ret;
if (ret != sizeof(pin)) {
usb_audio_err(chip,
"setting selector (id %d) unexpected length %d\n",
selector_id, ret);
return -EINVAL;
}
ret = uac_clock_selector_get_val(chip, selector_id, iface_no);
if (ret < 0)
return ret;
if (ret != pin) {
usb_audio_err(chip,
"setting selector (id %d) to %x failed (current: %d)\n",
selector_id, pin, ret);
return -EINVAL;
}
return ret;
}
static bool uac_clock_source_is_valid_quirk(struct snd_usb_audio *chip,
const struct audioformat *fmt,
int source_id)
{
bool ret = false;
int count;
unsigned char data;
struct usb_device *dev = chip->dev;
union uac23_clock_source_desc *cs_desc;
struct usb_host_interface *ctrl_intf;
ctrl_intf = snd_usb_find_ctrl_interface(chip, fmt->iface);
cs_desc = snd_usb_find_clock_source(chip, source_id, fmt);
if (!cs_desc)
return false;
if (fmt->protocol == UAC_VERSION_2) {
/*
* Assume the clock is valid if clock source supports only one
* single sample rate, the terminal is connected directly to it
* (there is no clock selector) and clock type is internal.
* This is to deal with some Denon DJ controllers that always
* reports that clock is invalid.
*/
if (fmt->nr_rates == 1 &&
(fmt->clock & 0xff) == cs_desc->v2.bClockID &&
(cs_desc->v2.bmAttributes & 0x3) !=
UAC_CLOCK_SOURCE_TYPE_EXT)
return true;
}
/*
* MOTU MicroBook IIc
* Sample rate changes takes more than 2 seconds for this device. Clock
* validity request returns false during that period.
*/
if (chip->usb_id == USB_ID(0x07fd, 0x0004)) {
count = 0;
while ((!ret) && (count < 50)) {
int err;
msleep(100);
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(ctrl_intf) | (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 false;
}
ret = !!data;
count++;
}
}
return ret;
}
static bool uac_clock_source_is_valid(struct snd_usb_audio *chip,
const struct audioformat *fmt,
int source_id)
{
int err;
unsigned char data;
struct usb_device *dev = chip->dev;
u32 bmControls;
union uac23_clock_source_desc *cs_desc;
struct usb_host_interface *ctrl_intf;
ctrl_intf = snd_usb_find_ctrl_interface(chip, fmt->iface);
cs_desc = snd_usb_find_clock_source(chip, source_id, fmt);
if (!cs_desc)
return false;
if (fmt->protocol == UAC_VERSION_3)
bmControls = le32_to_cpu(cs_desc->v3.bmControls);
else
bmControls = cs_desc->v2.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 true;
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(ctrl_intf) | (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 false;
}
if (data)
return true;
else
return uac_clock_source_is_valid_quirk(chip, fmt, source_id);
}
static int __uac_clock_find_source(struct snd_usb_audio *chip,
const struct audioformat *fmt, int entity_id,
unsigned long *visited, bool validate)
{
union uac23_clock_source_desc *source;
union uac23_clock_selector_desc *selector;
union uac23_clock_multiplier_desc *multiplier;
int ret, i, cur, err, pins, clock_id;
const u8 *sources;
int proto = fmt->protocol;
bool readable, writeable;
u32 bmControls;
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 at is a clock source already */
source = snd_usb_find_clock_source(chip, entity_id, fmt);
if (source) {
entity_id = GET_VAL(source, proto, bClockID);
if (validate && !uac_clock_source_is_valid(chip, fmt,
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, entity_id, fmt);
if (selector) {
pins = GET_VAL(selector, proto, bNrInPins);
clock_id = GET_VAL(selector, proto, bClockID);
sources = GET_VAL(selector, proto, baCSourceID);
cur = 0;
if (proto == UAC_VERSION_3)
bmControls = le32_to_cpu(*(__le32 *)(&selector->v3.baCSourceID[0] + pins));
else
bmControls = *(__u8 *)(&selector->v2.baCSourceID[0] + pins);
readable = uac_v2v3_control_is_readable(bmControls,
UAC2_CX_CLOCK_SELECTOR);
writeable = uac_v2v3_control_is_writeable(bmControls,
UAC2_CX_CLOCK_SELECTOR);
if (pins == 1) {
ret = 1;
goto find_source;
}
/* for now just warn about buggy device */
if (!readable)
usb_audio_warn(chip,
"%s(): clock selector control is not readable, id %d\n",
__func__, clock_id);
/* the entity ID we are looking at is a selector.
* find out what it currently selects */
ret = uac_clock_selector_get_val(chip, clock_id, fmt->iface);
if (ret < 0) {
if (!chip->autoclock)
return ret;
goto find_others;
}
/* Selector values are one-based */
if (ret > pins || ret < 1) {
usb_audio_err(chip,
"%s(): selector reported illegal value, id %d, ret %d\n",
__func__, clock_id, ret);
if (!chip->autoclock)
return -EINVAL;
goto find_others;
}
find_source:
cur = ret;
ret = __uac_clock_find_source(chip, fmt,
sources[ret - 1],
visited, validate);
if (ret > 0) {
/* Skip setting clock selector again for some devices */
if (chip->quirk_flags & QUIRK_FLAG_SKIP_CLOCK_SELECTOR ||
!writeable)
return ret;
err = uac_clock_selector_set_val(chip, entity_id, cur, fmt->iface);
if (err < 0) {
if (pins == 1) {
usb_audio_dbg(chip,
"%s(): selector returned an error, "
"assuming a firmware bug, id %d, ret %d\n",
__func__, clock_id, err);
return ret;
}
return err;
}
}
if (!validate || ret > 0 || !chip->autoclock)
return ret;
find_others:
if (!writeable)
return -ENXIO;
/* The current clock source is invalid, try others. */
for (i = 1; i <= pins; i++) {
if (i == cur)
continue;
ret = __uac_clock_find_source(chip, fmt,
sources[i - 1],
visited, true);
if (ret < 0)
continue;
err = uac_clock_selector_set_val(chip, entity_id, i, fmt->iface);
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, entity_id, fmt);
if (multiplier)
return __uac_clock_find_source(chip, fmt,
GET_VAL(multiplier, proto, bCSourceID),
visited, validate);
return -EINVAL;
}
/*
* For all kinds of sample rate settings and other device queries,
* the clock source (end-leaf) must be used. However, clock selectors,
* clock multipliers and sample rate converters may be specified as
* clock source input to terminal. This functions walks the clock path
* to its end and tries to find the source.
*
* The 'visited' bitfield is used internally to detect recursive loops.
*
* Returns the clock source UnitID (>=0) on success, or an error.
*/
int snd_usb_clock_find_source(struct snd_usb_audio *chip,
const struct audioformat *fmt, bool validate)
{
DECLARE_BITMAP(visited, 256);
memset(visited, 0, sizeof(visited));
switch (fmt->protocol) {
case UAC_VERSION_2:
case UAC_VERSION_3:
return __uac_clock_find_source(chip, fmt, fmt->clock, visited,
validate);
default:
return -EINVAL;
}
}
static int set_sample_rate_v1(struct snd_usb_audio *chip,
const struct audioformat *fmt, int rate)
{
struct usb_device *dev = chip->dev;
unsigned char data[3];
int err, crate;
/* if endpoint doesn't have sampling rate control, bail out */
if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
return 0;
data[0] = rate;
data[1] = rate >> 8;
data[2] = rate >> 16;
err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
UAC_EP_CS_ATTR_SAMPLE_RATE << 8,
fmt->endpoint, data, sizeof(data));
if (err < 0) {
dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
fmt->iface, fmt->altsetting, rate, fmt->endpoint);
return err;
}
/* Don't check the sample rate for devices which we know don't
* support reading */
if (chip->quirk_flags & QUIRK_FLAG_GET_SAMPLE_RATE)
return 0;
/* the firmware is likely buggy, don't repeat to fail too many times */
if (chip->sample_rate_read_error > 2)
return 0;
err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
UAC_EP_CS_ATTR_SAMPLE_RATE << 8,
fmt->endpoint, data, sizeof(data));
if (err < 0) {
dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
fmt->iface, fmt->altsetting, fmt->endpoint);
chip->sample_rate_read_error++;
return 0; /* some devices don't support reading */
}
crate = data[0] | (data[1] << 8) | (data[2] << 16);
if (!crate) {
dev_info(&dev->dev, "failed to read current rate; disabling the check\n");
chip->sample_rate_read_error = 3; /* three strikes, see above */
return 0;
}
if (crate != rate) {
dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
// runtime->rate = crate;
}
return 0;
}
static int get_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
int altsetting, int clock)
{
struct usb_device *dev = chip->dev;
__le32 data;
int err;
struct usb_host_interface *ctrl_intf;
ctrl_intf = snd_usb_find_ctrl_interface(chip, iface);
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_SAM_FREQ << 8,
snd_usb_ctrl_intf(ctrl_intf) | (clock << 8),
&data, sizeof(data));
if (err < 0) {
dev_warn(&dev->dev, "%d:%d: cannot get freq (v2/v3): err %d\n",
iface, altsetting, err);
return 0;
}
return le32_to_cpu(data);
}
/*
* Try to set the given sample rate:
*
* Return 0 if the clock source is read-only, the actual rate on success,
* or a negative error code.
*
* This function gets called from format.c to validate each sample rate, too.
* Hence no message is shown upon error
*/
int snd_usb_set_sample_rate_v2v3(struct snd_usb_audio *chip,
const struct audioformat *fmt,
int clock, int rate)
{
bool writeable;
u32 bmControls;
__le32 data;
int err;
union uac23_clock_source_desc *cs_desc;
struct usb_host_interface *ctrl_intf;
ctrl_intf = snd_usb_find_ctrl_interface(chip, fmt->iface);
cs_desc = snd_usb_find_clock_source(chip, clock, fmt);
if (!cs_desc)
return 0;
if (fmt->protocol == UAC_VERSION_3)
bmControls = le32_to_cpu(cs_desc->v3.bmControls);
else
bmControls = cs_desc->v2.bmControls;
writeable = uac_v2v3_control_is_writeable(bmControls,
UAC2_CS_CONTROL_SAM_FREQ);
if (!writeable)
return 0;
data = cpu_to_le32(rate);
err = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0), UAC2_CS_CUR,
USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
UAC2_CS_CONTROL_SAM_FREQ << 8,
snd_usb_ctrl_intf(ctrl_intf) | (clock << 8),
&data, sizeof(data));
if (err < 0)
return err;
return get_sample_rate_v2v3(chip, fmt->iface, fmt->altsetting, clock);
}
static int set_sample_rate_v2v3(struct snd_usb_audio *chip,
const struct audioformat *fmt, int rate)
{
int cur_rate, prev_rate;
int clock;
/* 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, 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, false);
/* Hardcoded sample rates */
if (chip->quirk_flags & QUIRK_FLAG_IGNORE_CLOCK_SOURCE)
return 0;
if (clock < 0)
return clock;
}
prev_rate = get_sample_rate_v2v3(chip, fmt->iface, fmt->altsetting, clock);
if (prev_rate == rate)
goto validation;
cur_rate = snd_usb_set_sample_rate_v2v3(chip, fmt, clock, rate);
if (cur_rate < 0) {
usb_audio_err(chip,
"%d:%d: cannot set freq %d (v2/v3): err %d\n",
fmt->iface, fmt->altsetting, rate, cur_rate);
return cur_rate;
}
if (!cur_rate)
cur_rate = prev_rate;
if (cur_rate != rate) {
usb_audio_dbg(chip,
"%d:%d: freq mismatch: req %d, clock runs @%d\n",
fmt->iface, fmt->altsetting, rate, cur_rate);
/* continue processing */
}
/* FIXME - TEAC devices require the immediate interface setup */
if (USB_ID_VENDOR(chip->usb_id) == 0x0644) {
bool cur_base_48k = (rate % 48000 == 0);
bool prev_base_48k = (prev_rate % 48000 == 0);
if (cur_base_48k != prev_base_48k) {
usb_set_interface(chip->dev, fmt->iface, fmt->altsetting);
if (chip->quirk_flags & QUIRK_FLAG_IFACE_DELAY)
msleep(50);
}
}
validation:
/* validate clock after rate change */
if (!uac_clock_source_is_valid(chip, fmt, clock))
return -ENXIO;
return 0;
}
int snd_usb_init_sample_rate(struct snd_usb_audio *chip,
const struct audioformat *fmt, int rate)
{
usb_audio_dbg(chip, "%d:%d Set sample rate %d, clock %d\n",
fmt->iface, fmt->altsetting, rate, fmt->clock);
switch (fmt->protocol) {
case UAC_VERSION_1:
default:
return set_sample_rate_v1(chip, fmt, rate);
case UAC_VERSION_3:
if (chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) {
if (rate != UAC3_BADD_SAMPLING_RATE)
return -ENXIO;
else
return 0;
}
fallthrough;
case UAC_VERSION_2:
return set_sample_rate_v2v3(chip, fmt, rate);
}
}
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