linux/sound/usb/clock.c
Takashi Iwai 3753fcc229 ALSA: usb-audio: Optimize TEAC clock quirk
Maris found out that the quirk for TEAC devices to work around the
clock setup is needed to apply only when the base clock is changed,
e.g. from 48000-based clocks (48000, 96000, 192000, 384000) to
44100-based clocks (44100, 88200, 176400, 352800), or vice versa,
while switching to another clock with the same base clock doesn't need
the (forcible) interface setup.

This patch implements the optimization for the TEAC clock quirk to
avoid the unnecessary interface re-setup.

Fixes: 5ce0b06ae5 ("ALSA: usb-audio: Workaround for clock setup on TEAC devices")
Reported-by: Maris Abele <maris7abele@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220531130749.30357-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2022-05-31 15:09:05 +02:00

617 lines
16 KiB
C

// 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, int proto) \
{ \
return find_uac_clock_desc(chip->ctrl_intf, id, validator, \
proto == UAC_VERSION_3 ? (type3) : (type2), \
proto); \
}
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)
{
unsigned char buf;
int ret;
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(chip) | (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 ret;
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(chip) | (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);
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;
cs_desc = snd_usb_find_clock_source(chip, source_id, fmt->protocol);
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(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 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;
cs_desc = snd_usb_find_clock_source(chip, source_id, fmt->protocol);
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(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 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;
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, proto);
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, proto);
if (selector) {
pins = GET_VAL(selector, proto, bNrInPins);
clock_id = GET_VAL(selector, proto, bClockID);
sources = GET_VAL(selector, proto, baCSourceID);
cur = 0;
if (pins == 1) {
ret = 1;
goto find_source;
}
/* 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);
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)
return ret;
err = uac_clock_selector_set_val(chip, entity_id, cur);
if (err < 0)
return err;
}
if (!validate || ret > 0 || !chip->autoclock)
return ret;
find_others:
/* 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);
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, proto);
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;
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(chip) | (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;
cs_desc = snd_usb_find_clock_source(chip, clock, fmt->protocol);
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(chip) | (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);
}
}