[linux-2.6-block.git] / sound / usb / clock.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"

static void *find_uac_clock_desc(struct usb_host_interface *iface, int id,
				 bool (*validator)(void *, int), u8 type)
{
	void *cs = NULL;

	while ((cs = snd_usb_find_csint_desc(iface->extra, iface->extralen,
					     cs, type))) {
		if (validator(cs, id))
			return cs;
	}

	return NULL;
}

static bool validate_clock_source_v2(void *p, int id)
{
	struct uac_clock_source_descriptor *cs = p;
	return cs->bLength == sizeof(*cs) && cs->bClockID == id;
}

static bool validate_clock_source_v3(void *p, int id)
{
	struct uac3_clock_source_descriptor *cs = p;
	return cs->bLength == sizeof(*cs) && cs->bClockID == id;
}

static bool validate_clock_selector_v2(void *p, int id)
{
	struct uac_clock_selector_descriptor *cs = p;
	return cs->bLength >= sizeof(*cs) && cs->bClockID == id &&
		cs->bLength == 7 + cs->bNrInPins;
}

static bool validate_clock_selector_v3(void *p, int id)
{
	struct uac3_clock_selector_descriptor *cs = p;
	return cs->bLength >= sizeof(*cs) && cs->bClockID == id &&
		cs->bLength == 11 + cs->bNrInPins;
}

static bool validate_clock_multiplier_v2(void *p, int id)
{
	struct uac_clock_multiplier_descriptor *cs = p;
	return cs->bLength == sizeof(*cs) && cs->bClockID == id;
}

static bool validate_clock_multiplier_v3(void *p, int id)
{
	struct uac3_clock_multiplier_descriptor *cs = p;
	return cs->bLength == sizeof(*cs) && cs->bClockID == id;
}

#define DEFINE_FIND_HELPER(name, obj, validator, type)		\
static obj *name(struct usb_host_interface *iface, int id)	\
{								\
	return find_uac_clock_desc(iface, id, validator, type);	\
}

DEFINE_FIND_HELPER(snd_usb_find_clock_source,
		   struct uac_clock_source_descriptor,
		   validate_clock_source_v2, UAC2_CLOCK_SOURCE);
DEFINE_FIND_HELPER(snd_usb_find_clock_source_v3,
		   struct uac3_clock_source_descriptor,
		   validate_clock_source_v3, UAC3_CLOCK_SOURCE);

DEFINE_FIND_HELPER(snd_usb_find_clock_selector,
		   struct uac_clock_selector_descriptor,
		   validate_clock_selector_v2, UAC2_CLOCK_SELECTOR);
DEFINE_FIND_HELPER(snd_usb_find_clock_selector_v3,
		   struct uac3_clock_selector_descriptor,
		   validate_clock_selector_v3, UAC3_CLOCK_SELECTOR);

DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier,
		   struct uac_clock_multiplier_descriptor,
		   validate_clock_multiplier_v2, UAC2_CLOCK_MULTIPLIER);
DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier_v3,
		   struct uac3_clock_multiplier_descriptor,
		   validate_clock_multiplier_v3, 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(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 __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;
}

static int __uac3_clock_find_source(struct snd_usb_audio *chip, int entity_id,
				   unsigned long *visited, bool validate)
{
	struct uac3_clock_source_descriptor *source;
	struct uac3_clock_selector_descriptor *selector;
	struct uac3_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_v3(chip->ctrl_intf, entity_id);
	if (source) {
		entity_id = source->bClockID;
		if (validate && !uac_clock_source_is_valid(chip, UAC_VERSION_3,
								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_v3(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 = __uac3_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 = __uac3_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_v3(chip->ctrl_intf,
						      entity_id);
	if (multiplier)
		return __uac3_clock_find_source(chip, multiplier->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, int protocol,
			      int entity_id, bool validate)
{
	DECLARE_BITMAP(visited, 256);
	memset(visited, 0, sizeof(visited));

	switch (protocol) {
	case UAC_VERSION_2:
		return __uac_clock_find_source(chip, entity_id, visited,
					       validate);
	case UAC_VERSION_3:
		return __uac3_clock_find_source(chip, entity_id, visited,
					       validate);
	default:
		return -EINVAL;
	}
}

static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface,
			      struct usb_host_interface *alts,
			      struct audioformat *fmt, int rate)
{
	struct usb_device *dev = chip->dev;
	unsigned int ep;
	unsigned char data[3];
	int err, crate;

	if (get_iface_desc(alts)->bNumEndpoints < 1)
		return -EINVAL;
	ep = get_endpoint(alts, 0)->bEndpointAddress;

	/* 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, ep,
			      data, sizeof(data));
	if (err < 0) {
		dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
			iface, fmt->altsetting, rate, ep);
		return err;
	}

	/* Don't check the sample rate for devices which we know don't
	 * support reading */
	if (snd_usb_get_sample_rate_quirk(chip))
		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, ep,
			      data, sizeof(data));
	if (err < 0) {
		dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
			iface, fmt->altsetting, ep);
		chip->sample_rate_read_error++;
		return 0; /* some devices don't support reading */
	}

	crate = data[0] | (data[1] << 8) | (data[2] << 16);
	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);
}

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;
}

int snd_usb_init_sample_rate(struct snd_usb_audio *chip, int iface,
			     struct usb_host_interface *alts,
			     struct audioformat *fmt, int rate)
{
	switch (fmt->protocol) {
	case UAC_VERSION_1:
	default:
		return set_sample_rate_v1(chip, iface, alts, 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;
		}
	/* fall through */
	case UAC_VERSION_2:
		return set_sample_rate_v2v3(chip, iface, alts, fmt, rate);
	}
}
Commit	Line	Data
1a59d1b8	1	// SPDX-License-Identifier: GPL-2.0-or-later
79f920fb DM	2	/*
79f920fb DM	3	* Clock domain and sample rate management functions
79f920fb DM	4	*/
	5
	6	#include <linux/bitops.h>
	7	#include <linux/init.h>
79f920fb DM	8	#include <linux/string.h>
79f920fb DM	9	#include <linux/usb.h>
79f920fb DM	10	#include <linux/usb/audio.h>
79f920fb DM	11	#include <linux/usb/audio-v2.h>
9a2fe9b8	12	#include <linux/usb/audio-v3.h>
79f920fb DM	13
	14	#include <sound/core.h>
	15	#include <sound/info.h>
	16	#include <sound/pcm.h>
79f920fb DM	17
	18	#include "usbaudio.h"
	19	#include "card.h"
79f920fb	20	#include "helper.h"
f22aa949	21	#include "clock.h"
21bb5aaf	22	#include "quirks.h"
79f920fb	23
f7645bd6 TI	24	static void find_uac_clock_desc(struct usb_host_interface iface, int id,
f7645bd6 TI	25	bool (validator)(void , int), u8 type)
79f920fb	26	{
f7645bd6	27	void *cs = NULL;
79f920fb	28
f7645bd6 TI	29	while ((cs = snd_usb_find_csint_desc(iface->extra, iface->extralen,
	30	cs, type))) {
	31	if (validator(cs, id))
79f920fb DM	32	return cs;
	33	}
	34
	35	return NULL;
	36	}
	37
f7645bd6	38	static bool validate_clock_source_v2(void *p, int id)
9a2fe9b8	39	{
f7645bd6	40	struct uac_clock_source_descriptor *cs = p;
f5d76e9c	41	return cs->bLength == sizeof(*cs) && cs->bClockID == id;
9a2fe9b8 RB	42	}
9a2fe9b8 RB	43
f7645bd6	44	static bool validate_clock_source_v3(void *p, int id)
79f920fb	45	{
f7645bd6	46	struct uac3_clock_source_descriptor *cs = p;
b580fbff	47	return cs->bLength == sizeof(*cs) && cs->bClockID == id;
79f920fb DM	48	}
79f920fb DM	49
f7645bd6	50	static bool validate_clock_selector_v2(void *p, int id)
9a2fe9b8	51	{
f7645bd6 TI	52	struct uac_clock_selector_descriptor *cs = p;
f7645bd6 TI	53	return cs->bLength >= sizeof(*cs) && cs->bClockID == id &&
f5d76e9c	54	cs->bLength == 7 + cs->bNrInPins;
9a2fe9b8 RB	55	}
9a2fe9b8 RB	56
f7645bd6	57	static bool validate_clock_selector_v3(void *p, int id)
79f920fb	58	{
f7645bd6	59	struct uac3_clock_selector_descriptor *cs = p;
b580fbff TI	60	return cs->bLength >= sizeof(*cs) && cs->bClockID == id &&
b580fbff TI	61	cs->bLength == 11 + cs->bNrInPins;
79f920fb DM	62	}
79f920fb DM	63
f7645bd6	64	static bool validate_clock_multiplier_v2(void *p, int id)
9a2fe9b8	65	{
f7645bd6	66	struct uac_clock_multiplier_descriptor *cs = p;
f5d76e9c	67	return cs->bLength == sizeof(*cs) && cs->bClockID == id;
f7645bd6	68	}
9a2fe9b8	69
f7645bd6 TI	70	static bool validate_clock_multiplier_v3(void *p, int id)
	71	{
	72	struct uac3_clock_multiplier_descriptor *cs = p;
b580fbff	73	return cs->bLength == sizeof(*cs) && cs->bClockID == id;
f7645bd6	74	}
9a2fe9b8	75
f7645bd6 TI	76	#define DEFINE_FIND_HELPER(name, obj, validator, type) \
	77	static obj name(struct usb_host_interface iface, int id) \
	78	{ \
	79	return find_uac_clock_desc(iface, id, validator, type); \
9a2fe9b8 RB	80	}
9a2fe9b8 RB	81
f7645bd6 TI	82	DEFINE_FIND_HELPER(snd_usb_find_clock_source,
	83	struct uac_clock_source_descriptor,
	84	validate_clock_source_v2, UAC2_CLOCK_SOURCE);
	85	DEFINE_FIND_HELPER(snd_usb_find_clock_source_v3,
	86	struct uac3_clock_source_descriptor,
	87	validate_clock_source_v3, UAC3_CLOCK_SOURCE);
	88
	89	DEFINE_FIND_HELPER(snd_usb_find_clock_selector,
	90	struct uac_clock_selector_descriptor,
	91	validate_clock_selector_v2, UAC2_CLOCK_SELECTOR);
	92	DEFINE_FIND_HELPER(snd_usb_find_clock_selector_v3,
	93	struct uac3_clock_selector_descriptor,
	94	validate_clock_selector_v3, UAC3_CLOCK_SELECTOR);
	95
	96	DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier,
	97	struct uac_clock_multiplier_descriptor,
	98	validate_clock_multiplier_v2, UAC2_CLOCK_MULTIPLIER);
	99	DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier_v3,
	100	struct uac3_clock_multiplier_descriptor,
	101	validate_clock_multiplier_v3, UAC3_CLOCK_MULTIPLIER);
	102
79f920fb DM	103	static int uac_clock_selector_get_val(struct snd_usb_audio *chip, int selector_id)
	104	{
	105	unsigned char buf;
	106	int ret;
	107
	108	ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
	109	UAC2_CS_CUR,
	110	USB_RECIP_INTERFACE \| USB_TYPE_CLASS \| USB_DIR_IN,
11bcbc44 DM	111	UAC2_CX_CLOCK_SELECTOR << 8,
11bcbc44 DM	112	snd_usb_ctrl_intf(chip) \| (selector_id << 8),
17d900c4	113	&buf, sizeof(buf));
79f920fb DM	114
	115	if (ret < 0)
	116	return ret;
	117
	118	return buf;
	119	}
	120
8c55af3f EZ	121	static int uac_clock_selector_set_val(struct snd_usb_audio *chip, int selector_id,
	122	unsigned char pin)
	123	{
	124	int ret;
	125
	126	ret = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0),
	127	UAC2_CS_CUR,
	128	USB_RECIP_INTERFACE \| USB_TYPE_CLASS \| USB_DIR_OUT,
	129	UAC2_CX_CLOCK_SELECTOR << 8,
	130	snd_usb_ctrl_intf(chip) \| (selector_id << 8),
	131	&pin, sizeof(pin));
	132	if (ret < 0)
	133	return ret;
	134
	135	if (ret != sizeof(pin)) {
0ba41d91 TI	136	usb_audio_err(chip,
	137	"setting selector (id %d) unexpected length %d\n",
	138	selector_id, ret);
8c55af3f EZ	139	return -EINVAL;
	140	}
	141
	142	ret = uac_clock_selector_get_val(chip, selector_id);
	143	if (ret < 0)
	144	return ret;
	145
	146	if (ret != pin) {
0ba41d91 TI	147	usb_audio_err(chip,
	148	"setting selector (id %d) to %x failed (current: %d)\n",
	149	selector_id, pin, ret);
8c55af3f EZ	150	return -EINVAL;
	151	}
	152
	153	return ret;
	154	}
	155
9a2fe9b8 RB	156	static bool uac_clock_source_is_valid(struct snd_usb_audio *chip,
	157	int protocol,
	158	int source_id)
79f920fb DM	159	{
	160	int err;
	161	unsigned char data;
	162	struct usb_device *dev = chip->dev;
9a2fe9b8 RB	163	u32 bmControls;
	164
	165	if (protocol == UAC_VERSION_3) {
	166	struct uac3_clock_source_descriptor *cs_desc =
	167	snd_usb_find_clock_source_v3(chip->ctrl_intf, source_id);
	168
	169	if (!cs_desc)
	170	return 0;
	171	bmControls = le32_to_cpu(cs_desc->bmControls);
	172	} else { /* UAC_VERSION_1/2 */
	173	struct uac_clock_source_descriptor *cs_desc =
	174	snd_usb_find_clock_source(chip->ctrl_intf, source_id);
	175
	176	if (!cs_desc)
	177	return 0;
	178	bmControls = cs_desc->bmControls;
	179	}
3bc6fbc7 DM	180
3bc6fbc7 DM	181	/* If a clock source can't tell us whether it's valid, we assume it is */
9a2fe9b8	182	if (!uac_v2v3_control_is_readable(bmControls,
21e9b3e9	183	UAC2_CS_CONTROL_CLOCK_VALID))
3bc6fbc7	184	return 1;
79f920fb DM	185
	186	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
	187	USB_TYPE_CLASS \| USB_RECIP_INTERFACE \| USB_DIR_IN,
11bcbc44 DM	188	UAC2_CS_CONTROL_CLOCK_VALID << 8,
11bcbc44 DM	189	snd_usb_ctrl_intf(chip) \| (source_id << 8),
17d900c4	190	&data, sizeof(data));
79f920fb DM	191
79f920fb DM	192	if (err < 0) {
0ba41d91 TI	193	dev_warn(&dev->dev,
0ba41d91 TI	194	"%s(): cannot get clock validity for id %d\n",
79f920fb	195	__func__, source_id);
3bc6fbc7	196	return 0;
79f920fb DM	197	}
	198
	199	return !!data;
	200	}
	201
9a2fe9b8 RB	202	static int __uac_clock_find_source(struct snd_usb_audio *chip, int entity_id,
9a2fe9b8 RB	203	unsigned long *visited, bool validate)
79f920fb DM	204	{
	205	struct uac_clock_source_descriptor *source;
	206	struct uac_clock_selector_descriptor *selector;
	207	struct uac_clock_multiplier_descriptor *multiplier;
	208
	209	entity_id &= 0xff;
	210
	211	if (test_and_set_bit(entity_id, visited)) {
0ba41d91 TI	212	usb_audio_warn(chip,
	213	"%s(): recursive clock topology detected, id %d.\n",
	214	__func__, entity_id);
79f920fb DM	215	return -EINVAL;
	216	}
	217
	218	/* first, see if the ID we're looking for is a clock source already */
3d8d4dcf	219	source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id);
06ffc1eb EZ	220	if (source) {
06ffc1eb EZ	221	entity_id = source->bClockID;
9a2fe9b8 RB	222	if (validate && !uac_clock_source_is_valid(chip, UAC_VERSION_2,
9a2fe9b8 RB	223	entity_id)) {
0ba41d91 TI	224	usb_audio_err(chip,
	225	"clock source %d is not valid, cannot use\n",
	226	entity_id);
06ffc1eb EZ	227	return -ENXIO;
	228	}
	229	return entity_id;
	230	}
79f920fb	231
3d8d4dcf	232	selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
79f920fb	233	if (selector) {
8c55af3f	234	int ret, i, cur;
79f920fb DM	235
	236	/* the entity ID we are looking for is a selector.
	237	* find out what it currently selects */
	238	ret = uac_clock_selector_get_val(chip, selector->bClockID);
	239	if (ret < 0)
	240	return ret;
	241
157a57b6 DM	242	/* Selector values are one-based */
157a57b6 DM	243
79f920fb	244	if (ret > selector->bNrInPins \|\| ret < 1) {
0ba41d91	245	usb_audio_err(chip,
79f920fb DM	246	"%s(): selector reported illegal value, id %d, ret %d\n",
	247	__func__, selector->bClockID, ret);
	248
	249	return -EINVAL;
	250	}
	251
8c55af3f EZ	252	cur = ret;
8c55af3f EZ	253	ret = __uac_clock_find_source(chip, selector->baCSourceID[ret - 1],
06ffc1eb	254	visited, validate);
ef02e29b	255	if (!validate \|\| ret > 0 \|\| !chip->autoclock)
8c55af3f EZ	256	return ret;
	257
	258	/* The current clock source is invalid, try others. */
	259	for (i = 1; i <= selector->bNrInPins; i++) {
	260	int err;
	261
	262	if (i == cur)
	263	continue;
	264
	265	ret = __uac_clock_find_source(chip, selector->baCSourceID[i - 1],
	266	visited, true);
	267	if (ret < 0)
	268	continue;
	269
	270	err = uac_clock_selector_set_val(chip, entity_id, i);
	271	if (err < 0)
	272	continue;
	273
0ba41d91 TI	274	usb_audio_info(chip,
	275	"found and selected valid clock source %d\n",
	276	ret);
8c55af3f EZ	277	return ret;
	278	}
	279
	280	return -ENXIO;
79f920fb DM	281	}
	282
	283	/* FIXME: multipliers only act as pass-thru element for now */
3d8d4dcf	284	multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id);
79f920fb	285	if (multiplier)
3d8d4dcf	286	return __uac_clock_find_source(chip, multiplier->bCSourceID,
06ffc1eb	287	visited, validate);
79f920fb DM	288
	289	return -EINVAL;
	290	}
	291
9a2fe9b8 RB	292	static int __uac3_clock_find_source(struct snd_usb_audio *chip, int entity_id,
	293	unsigned long *visited, bool validate)
	294	{
	295	struct uac3_clock_source_descriptor *source;
	296	struct uac3_clock_selector_descriptor *selector;
	297	struct uac3_clock_multiplier_descriptor *multiplier;
	298
	299	entity_id &= 0xff;
	300
	301	if (test_and_set_bit(entity_id, visited)) {
	302	usb_audio_warn(chip,
	303	"%s(): recursive clock topology detected, id %d.\n",
	304	__func__, entity_id);
	305	return -EINVAL;
	306	}
	307
	308	/* first, see if the ID we're looking for is a clock source already */
	309	source = snd_usb_find_clock_source_v3(chip->ctrl_intf, entity_id);
	310	if (source) {
	311	entity_id = source->bClockID;
	312	if (validate && !uac_clock_source_is_valid(chip, UAC_VERSION_3,
	313	entity_id)) {
	314	usb_audio_err(chip,
	315	"clock source %d is not valid, cannot use\n",
	316	entity_id);
	317	return -ENXIO;
	318	}
	319	return entity_id;
	320	}
	321
	322	selector = snd_usb_find_clock_selector_v3(chip->ctrl_intf, entity_id);
	323	if (selector) {
	324	int ret, i, cur;
	325
	326	/* the entity ID we are looking for is a selector.
	327	* find out what it currently selects */
	328	ret = uac_clock_selector_get_val(chip, selector->bClockID);
	329	if (ret < 0)
	330	return ret;
	331
	332	/* Selector values are one-based */
	333
	334	if (ret > selector->bNrInPins \|\| ret < 1) {
	335	usb_audio_err(chip,
	336	"%s(): selector reported illegal value, id %d, ret %d\n",
	337	__func__, selector->bClockID, ret);
	338
	339	return -EINVAL;
	340	}
	341
	342	cur = ret;
	343	ret = __uac3_clock_find_source(chip, selector->baCSourceID[ret - 1],
	344	visited, validate);
	345	if (!validate \|\| ret > 0 \|\| !chip->autoclock)
	346	return ret;
	347
	348	/* The current clock source is invalid, try others. */
	349	for (i = 1; i <= selector->bNrInPins; i++) {
	350	int err;
	351
	352	if (i == cur)
	353	continue;
	354
	355	ret = __uac3_clock_find_source(chip, selector->baCSourceID[i - 1],
356	visited, true);
357	if (ret < 0)
358	continue;
359
360	err = uac_clock_selector_set_val(chip, entity_id, i);
361	if (err < 0)
362	continue;
363
364	usb_audio_info(chip,
365	"found and selected valid clock source %d\n",
366	ret);
367	return ret;
368	}
369
370	return -ENXIO;
371	}
372
373	/* FIXME: multipliers only act as pass-thru element for now */
374	multiplier = snd_usb_find_clock_multiplier_v3(chip->ctrl_intf,
375	entity_id);
376	if (multiplier)
377	return __uac3_clock_find_source(chip, multiplier->bCSourceID,
378	visited, validate);
379
380	return -EINVAL;
381	}
382
157a57b6 DM	383	/*
	384	* For all kinds of sample rate settings and other device queries,
	385	* the clock source (end-leaf) must be used. However, clock selectors,
	386	* clock multipliers and sample rate converters may be specified as
	387	* clock source input to terminal. This functions walks the clock path
	388	* to its end and tries to find the source.
	389	*
	390	* The 'visited' bitfield is used internally to detect recursive loops.
	391	*
	392	* Returns the clock source UnitID (>=0) on success, or an error.
	393	*/
9a2fe9b8 RB	394	int snd_usb_clock_find_source(struct snd_usb_audio *chip, int protocol,
9a2fe9b8 RB	395	int entity_id, bool validate)
79f920fb DM	396	{
	397	DECLARE_BITMAP(visited, 256);
	398	memset(visited, 0, sizeof(visited));
9a2fe9b8 RB	399
	400	switch (protocol) {
	401	case UAC_VERSION_2:
	402	return __uac_clock_find_source(chip, entity_id, visited,
	403	validate);
	404	case UAC_VERSION_3:
	405	return __uac3_clock_find_source(chip, entity_id, visited,
	406	validate);
	407	default:
	408	return -EINVAL;
	409	}
79f920fb DM	410	}
	411
	412	static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface,
	413	struct usb_host_interface *alts,
	414	struct audioformat *fmt, int rate)
	415	{
	416	struct usb_device *dev = chip->dev;
	417	unsigned int ep;
	418	unsigned char data[3];
	419	int err, crate;
	420
447d6275 TI	421	if (get_iface_desc(alts)->bNumEndpoints < 1)
447d6275 TI	422	return -EINVAL;
79f920fb DM	423	ep = get_endpoint(alts, 0)->bEndpointAddress;
	424
	425	/* if endpoint doesn't have sampling rate control, bail out */
d32d552e	426	if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
79f920fb	427	return 0;
79f920fb DM	428
	429	data[0] = rate;
	430	data[1] = rate >> 8;
	431	data[2] = rate >> 16;
f25ecf8f TI	432	err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
	433	USB_TYPE_CLASS \| USB_RECIP_ENDPOINT \| USB_DIR_OUT,
	434	UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
	435	data, sizeof(data));
	436	if (err < 0) {
0ba41d91 TI	437	dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
0ba41d91 TI	438	iface, fmt->altsetting, rate, ep);
79f920fb DM	439	return err;
	440	}
	441
b62b9980 JT	442	/* Don't check the sample rate for devices which we know don't
	443	* support reading */
	444	if (snd_usb_get_sample_rate_quirk(chip))
	445	return 0;
57dd5414 TI	446	/* the firmware is likely buggy, don't repeat to fail too many times */
	447	if (chip->sample_rate_read_error > 2)
	448	return 0;
b62b9980	449
f25ecf8f TI	450	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
	451	USB_TYPE_CLASS \| USB_RECIP_ENDPOINT \| USB_DIR_IN,
	452	UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
	453	data, sizeof(data));
	454	if (err < 0) {
0ba41d91 TI	455	dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
0ba41d91 TI	456	iface, fmt->altsetting, ep);
57dd5414	457	chip->sample_rate_read_error++;
79f920fb DM	458	return 0; /* some devices don't support reading */
	459	}
	460
	461	crate = data[0] \| (data[1] << 8) \| (data[2] << 16);
	462	if (crate != rate) {
0ba41d91	463	dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
79f920fb DM	464	// runtime->rate = crate;
	465	}
	466
	467	return 0;
	468	}
	469
9a2fe9b8	470	static int get_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
7c517465 TI	471	int altsetting, int clock)
	472	{
	473	struct usb_device *dev = chip->dev;
f6a8bc70	474	__le32 data;
7c517465 TI	475	int err;
	476
	477	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
	478	USB_TYPE_CLASS \| USB_RECIP_INTERFACE \| USB_DIR_IN,
	479	UAC2_CS_CONTROL_SAM_FREQ << 8,
	480	snd_usb_ctrl_intf(chip) \| (clock << 8),
f6a8bc70	481	&data, sizeof(data));
7c517465	482	if (err < 0) {
9a2fe9b8	483	dev_warn(&dev->dev, "%d:%d: cannot get freq (v2/v3): err %d\n",
0ba41d91	484	iface, altsetting, err);
7c517465 TI	485	return 0;
	486	}
	487
f6a8bc70	488	return le32_to_cpu(data);
7c517465 TI	489	}
7c517465 TI	490
9a2fe9b8	491	static int set_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
79f920fb DM	492	struct usb_host_interface *alts,
	493	struct audioformat *fmt, int rate)
	494	{
	495	struct usb_device *dev = chip->dev;
f6a8bc70	496	__le32 data;
690a863f	497	int err, cur_rate, prev_rate;
8c55af3f	498	int clock;
1dc669fe	499	bool writeable;
9a2fe9b8	500	u32 bmControls;
79f920fb	501
58cabe87 AG	502	/* First, try to find a valid clock. This may trigger
	503	* automatic clock selection if the current clock is not
	504	* valid.
	505	*/
9a2fe9b8 RB	506	clock = snd_usb_clock_find_source(chip, fmt->protocol,
9a2fe9b8 RB	507	fmt->clock, true);
58cabe87 AG	508	if (clock < 0) {
	509	/* We did not find a valid clock, but that might be
	510	* because the current sample rate does not match an
	511	* external clock source. Try again without validation
	512	* and we will do another validation after setting the
	513	* rate.
	514	*/
	515	clock = snd_usb_clock_find_source(chip, fmt->protocol,
	516	fmt->clock, false);
	517	if (clock < 0)
	518	return clock;
	519	}
79f920fb	520
9a2fe9b8	521	prev_rate = get_sample_rate_v2v3(chip, iface, fmt->altsetting, clock);
fa92dd77	522	if (prev_rate == rate)
58cabe87	523	goto validation;
690a863f	524
9a2fe9b8 RB	525	if (fmt->protocol == UAC_VERSION_3) {
	526	struct uac3_clock_source_descriptor *cs_desc;
	527
	528	cs_desc = snd_usb_find_clock_source_v3(chip->ctrl_intf, clock);
	529	bmControls = le32_to_cpu(cs_desc->bmControls);
	530	} else {
	531	struct uac_clock_source_descriptor *cs_desc;
	532
	533	cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, clock);
	534	bmControls = cs_desc->bmControls;
	535	}
	536
21e9b3e9 AC	537	writeable = uac_v2v3_control_is_writeable(bmControls,
21e9b3e9 AC	538	UAC2_CS_CONTROL_SAM_FREQ);
1dc669fe EZ	539	if (writeable) {
	540	data = cpu_to_le32(rate);
	541	err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
	542	USB_TYPE_CLASS \| USB_RECIP_INTERFACE \| USB_DIR_OUT,
	543	UAC2_CS_CONTROL_SAM_FREQ << 8,
	544	snd_usb_ctrl_intf(chip) \| (clock << 8),
	545	&data, sizeof(data));
	546	if (err < 0) {
0ba41d91	547	usb_audio_err(chip,
9a2fe9b8	548	"%d:%d: cannot set freq %d (v2/v3): err %d\n",
0ba41d91	549	iface, fmt->altsetting, rate, err);
1dc669fe EZ	550	return err;
1dc669fe EZ	551	}
79f920fb	552
9a2fe9b8 RB	553	cur_rate = get_sample_rate_v2v3(chip, iface,
9a2fe9b8 RB	554	fmt->altsetting, clock);
1dc669fe EZ	555	} else {
	556	cur_rate = prev_rate;
	557	}
79f920fb	558
690a863f	559	if (cur_rate != rate) {
1dc669fe	560	if (!writeable) {
0ba41d91 TI	561	usb_audio_warn(chip,
	562	"%d:%d: freq mismatch (RO clock): req %d, clock runs @%d\n",
	563	iface, fmt->altsetting, rate, cur_rate);
1dc669fe EZ	564	return -ENXIO;
1dc669fe EZ	565	}
0ba41d91 TI	566	usb_audio_dbg(chip,
	567	"current rate %d is different from the runtime rate %d\n",
	568	cur_rate, rate);
690a863f TH	569	}
	570
	571	/* Some devices doesn't respond to sample rate changes while the
	572	* interface is active. */
	573	if (rate != prev_rate) {
	574	usb_set_interface(dev, iface, 0);
21bb5aaf	575	snd_usb_set_interface_quirk(dev);
690a863f	576	usb_set_interface(dev, iface, fmt->altsetting);
21bb5aaf	577	snd_usb_set_interface_quirk(dev);
690a863f	578	}
79f920fb	579
58cabe87 AG	580	validation:
	581	/* validate clock after rate change */
	582	if (!uac_clock_source_is_valid(chip, fmt->protocol, clock))
	583	return -ENXIO;
79f920fb DM	584	return 0;
	585	}
	586
	587	int snd_usb_init_sample_rate(struct snd_usb_audio *chip, int iface,
	588	struct usb_host_interface *alts,
	589	struct audioformat *fmt, int rate)
	590	{
8f898e92	591	switch (fmt->protocol) {
79f920fb	592	case UAC_VERSION_1:
a2acad82	593	default:
79f920fb DM	594	return set_sample_rate_v1(chip, iface, alts, fmt, rate);
79f920fb DM	595
9a2fe9b8	596	case UAC_VERSION_3:
17156f23 RB	597	if (chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) {
	598	if (rate != UAC3_BADD_SAMPLING_RATE)
	599	return -ENXIO;
	600	else
	601	return 0;
	602	}
	603	/* fall through */
	604	case UAC_VERSION_2:
9a2fe9b8	605	return set_sample_rate_v2v3(chip, iface, alts, fmt, rate);
79f920fb	606	}
79f920fb DM	607	}
79f920fb DM	608