// SPDX-License-Identifier: GPL-2.0-or-later

  /*
   *   USB Audio Driver for ALSA
   *
   *   Quirks and vendor-specific extensions for mixer interfaces
   *
   *   Copyright (c) 2002 by Takashi Iwai <tiwai@suse.de>
   *
   *   Many codes borrowed from audio.c by
   *	    Alan Cox (alan@lxorguk.ukuu.org.uk)
   *	    Thomas Sailer (sailer@ife.ee.ethz.ch)
   *

   *   Audio Advantage Micro II support added by:
   *	    Przemek Rudy (prudy1@o2.pl)

   */

  #include <linux/hid.h>

  #include <linux/init.h>

  #include <linux/math64.h>

  #include <linux/slab.h>

  #include <linux/usb.h>
  #include <linux/usb/audio.h>

  #include <sound/asoundef.h>

  #include <sound/core.h>
  #include <sound/control.h>
  #include <sound/hwdep.h>
  #include <sound/info.h>

  #include <sound/tlv.h>

  
  #include "usbaudio.h"

  #include "mixer.h"

  #include "mixer_quirks.h"

  #include "mixer_scarlett.h"

  #include "mixer_scarlett_gen2.h"

  #include "mixer_us16x08.h"

  #include "helper.h"

  struct std_mono_table {
  	unsigned int unitid, control, cmask;
  	int val_type;
  	const char *name;
  	snd_kcontrol_tlv_rw_t *tlv_callback;
  };

  /* This function allows for the creation of standard UAC controls.
   * See the quirks for M-Audio FTUs or Ebox-44.
   * If you don't want to set a TLV callback pass NULL.
   *
   * Since there doesn't seem to be a devices that needs a multichannel
   * version, we keep it mono for simplicity.
   */

  static int snd_create_std_mono_ctl_offset(struct usb_mixer_interface *mixer,

  				unsigned int unitid,
  				unsigned int control,
  				unsigned int cmask,
  				int val_type,

  				unsigned int idx_off,

  				const char *name,
  				snd_kcontrol_tlv_rw_t *tlv_callback)
  {

  	struct usb_mixer_elem_info *cval;
  	struct snd_kcontrol *kctl;
  
  	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
  	if (!cval)
  		return -ENOMEM;

  	snd_usb_mixer_elem_init_std(&cval->head, mixer, unitid);

  	cval->val_type = val_type;
  	cval->channels = 1;
  	cval->control = control;
  	cval->cmask = cmask;

  	cval->idx_off = idx_off;

  	/* get_min_max() is called only for integer volumes later,
  	 * so provide a short-cut for booleans */

  	cval->min = 0;
  	cval->max = 1;
  	cval->res = 0;
  	cval->dBmin = 0;
  	cval->dBmax = 0;
  
  	/* Create control */
  	kctl = snd_ctl_new1(snd_usb_feature_unit_ctl, cval);
  	if (!kctl) {
  		kfree(cval);
  		return -ENOMEM;
  	}
  
  	/* Set name */
  	snprintf(kctl->id.name, sizeof(kctl->id.name), name);

  	kctl->private_free = snd_usb_mixer_elem_free;

  
  	/* set TLV */
  	if (tlv_callback) {
  		kctl->tlv.c = tlv_callback;
  		kctl->vd[0].access |=
  			SNDRV_CTL_ELEM_ACCESS_TLV_READ |
  			SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
  	}
  	/* Add control to mixer */

  	return snd_usb_mixer_add_control(&cval->head, kctl);

  }

  static int snd_create_std_mono_ctl(struct usb_mixer_interface *mixer,
  				unsigned int unitid,
  				unsigned int control,
  				unsigned int cmask,
  				int val_type,
  				const char *name,
  				snd_kcontrol_tlv_rw_t *tlv_callback)
  {
  	return snd_create_std_mono_ctl_offset(mixer, unitid, control, cmask,
  		val_type, 0 /* Offset */, name, tlv_callback);
  }

  /*

   * Create a set of standard UAC controls from a table
   */
  static int snd_create_std_mono_table(struct usb_mixer_interface *mixer,
  				struct std_mono_table *t)
  {
  	int err;
  
  	while (t->name != NULL) {
  		err = snd_create_std_mono_ctl(mixer, t->unitid, t->control,
  				t->cmask, t->val_type, t->name, t->tlv_callback);
  		if (err < 0)
  			return err;
  		t++;
  	}
  
  	return 0;
  }

  static int add_single_ctl_with_resume(struct usb_mixer_interface *mixer,
  				      int id,
  				      usb_mixer_elem_resume_func_t resume,
  				      const struct snd_kcontrol_new *knew,
  				      struct usb_mixer_elem_list **listp)
  {
  	struct usb_mixer_elem_list *list;
  	struct snd_kcontrol *kctl;
  
  	list = kzalloc(sizeof(*list), GFP_KERNEL);
  	if (!list)
  		return -ENOMEM;
  	if (listp)
  		*listp = list;
  	list->mixer = mixer;
  	list->id = id;
  	list->resume = resume;
  	kctl = snd_ctl_new1(knew, list);
  	if (!kctl) {
  		kfree(list);
  		return -ENOMEM;
  	}
  	kctl->private_free = snd_usb_mixer_elem_free;
  	return snd_usb_mixer_add_control(list, kctl);
  }

  /*

   * Sound Blaster remote control configuration
   *
   * format of remote control data:
   * Extigy:       xx 00
   * Audigy 2 NX:  06 80 xx 00 00 00
   * Live! 24-bit: 06 80 xx yy 22 83
   */
  static const struct rc_config {
  	u32 usb_id;
  	u8  offset;
  	u8  length;
  	u8  packet_length;
  	u8  min_packet_length; /* minimum accepted length of the URB result */
  	u8  mute_mixer_id;
  	u32 mute_code;
  } rc_configs[] = {
  	{ USB_ID(0x041e, 0x3000), 0, 1, 2, 1,  18, 0x0013 }, /* Extigy       */
  	{ USB_ID(0x041e, 0x3020), 2, 1, 6, 6,  18, 0x0013 }, /* Audigy 2 NX  */
  	{ USB_ID(0x041e, 0x3040), 2, 2, 6, 6,  2,  0x6e91 }, /* Live! 24-bit */

  	{ USB_ID(0x041e, 0x3042), 0, 1, 1, 1,  1,  0x000d }, /* Usb X-Fi S51 */

  	{ USB_ID(0x041e, 0x30df), 0, 1, 1, 1,  1,  0x000d }, /* Usb X-Fi S51 Pro */

  	{ USB_ID(0x041e, 0x3237), 0, 1, 1, 1,  1,  0x000d }, /* Usb X-Fi S51 Pro */

  	{ USB_ID(0x041e, 0x3048), 2, 2, 6, 6,  2,  0x6e91 }, /* Toshiba SB0500 */
  };
  
  static void snd_usb_soundblaster_remote_complete(struct urb *urb)
  {
  	struct usb_mixer_interface *mixer = urb->context;
  	const struct rc_config *rc = mixer->rc_cfg;
  	u32 code;
  
  	if (urb->status < 0 || urb->actual_length < rc->min_packet_length)
  		return;
  
  	code = mixer->rc_buffer[rc->offset];
  	if (rc->length == 2)
  		code |= mixer->rc_buffer[rc->offset + 1] << 8;
  
  	/* the Mute button actually changes the mixer control */
  	if (code == rc->mute_code)
  		snd_usb_mixer_notify_id(mixer, rc->mute_mixer_id);
  	mixer->rc_code = code;
  	wmb();
  	wake_up(&mixer->rc_waitq);
  }
  
  static long snd_usb_sbrc_hwdep_read(struct snd_hwdep *hw, char __user *buf,
  				     long count, loff_t *offset)
  {
  	struct usb_mixer_interface *mixer = hw->private_data;
  	int err;
  	u32 rc_code;
  
  	if (count != 1 && count != 4)
  		return -EINVAL;
  	err = wait_event_interruptible(mixer->rc_waitq,
  				       (rc_code = xchg(&mixer->rc_code, 0)) != 0);
  	if (err == 0) {
  		if (count == 1)
  			err = put_user(rc_code, buf);
  		else
  			err = put_user(rc_code, (u32 __user *)buf);
  	}
  	return err < 0 ? err : count;
  }

  static __poll_t snd_usb_sbrc_hwdep_poll(struct snd_hwdep *hw, struct file *file,

  					    poll_table *wait)
  {
  	struct usb_mixer_interface *mixer = hw->private_data;
  
  	poll_wait(file, &mixer->rc_waitq, wait);

  	return mixer->rc_code ? EPOLLIN | EPOLLRDNORM : 0;

  }
  
  static int snd_usb_soundblaster_remote_init(struct usb_mixer_interface *mixer)
  {
  	struct snd_hwdep *hwdep;
  	int err, len, i;
  
  	for (i = 0; i < ARRAY_SIZE(rc_configs); ++i)
  		if (rc_configs[i].usb_id == mixer->chip->usb_id)
  			break;
  	if (i >= ARRAY_SIZE(rc_configs))
  		return 0;
  	mixer->rc_cfg = &rc_configs[i];
  
  	len = mixer->rc_cfg->packet_length;
  
  	init_waitqueue_head(&mixer->rc_waitq);
  	err = snd_hwdep_new(mixer->chip->card, "SB remote control", 0, &hwdep);
  	if (err < 0)
  		return err;
  	snprintf(hwdep->name, sizeof(hwdep->name),
  		 "%s remote control", mixer->chip->card->shortname);
  	hwdep->iface = SNDRV_HWDEP_IFACE_SB_RC;
  	hwdep->private_data = mixer;
  	hwdep->ops.read = snd_usb_sbrc_hwdep_read;
  	hwdep->ops.poll = snd_usb_sbrc_hwdep_poll;
  	hwdep->exclusive = 1;
  
  	mixer->rc_urb = usb_alloc_urb(0, GFP_KERNEL);
  	if (!mixer->rc_urb)
  		return -ENOMEM;
  	mixer->rc_setup_packet = kmalloc(sizeof(*mixer->rc_setup_packet), GFP_KERNEL);
  	if (!mixer->rc_setup_packet) {
  		usb_free_urb(mixer->rc_urb);
  		mixer->rc_urb = NULL;
  		return -ENOMEM;
  	}
  	mixer->rc_setup_packet->bRequestType =
  		USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE;
  	mixer->rc_setup_packet->bRequest = UAC_GET_MEM;
  	mixer->rc_setup_packet->wValue = cpu_to_le16(0);
  	mixer->rc_setup_packet->wIndex = cpu_to_le16(0);
  	mixer->rc_setup_packet->wLength = cpu_to_le16(len);
  	usb_fill_control_urb(mixer->rc_urb, mixer->chip->dev,
  			     usb_rcvctrlpipe(mixer->chip->dev, 0),
  			     (u8*)mixer->rc_setup_packet, mixer->rc_buffer, len,
  			     snd_usb_soundblaster_remote_complete, mixer);
  	return 0;
  }
  
  #define snd_audigy2nx_led_info		snd_ctl_boolean_mono_info
  
  static int snd_audigy2nx_led_get(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
  {

  	ucontrol->value.integer.value[0] = kcontrol->private_value >> 8;

  	return 0;
  }

  static int snd_audigy2nx_led_update(struct usb_mixer_interface *mixer,
  				    int value, int index)

  {

  	struct snd_usb_audio *chip = mixer->chip;
  	int err;

  	err = snd_usb_lock_shutdown(chip);
  	if (err < 0)
  		return err;

  	if (chip->usb_id == USB_ID(0x041e, 0x3042))
  		err = snd_usb_ctl_msg(chip->dev,
  			      usb_sndctrlpipe(chip->dev, 0), 0x24,

  			      USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_OTHER,

  			      !value, 0, NULL, 0);

  	/* USB X-Fi S51 Pro */

  	if (chip->usb_id == USB_ID(0x041e, 0x30df))
  		err = snd_usb_ctl_msg(chip->dev,
  			      usb_sndctrlpipe(chip->dev, 0), 0x24,

  			      USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_OTHER,

  			      !value, 0, NULL, 0);

  	else

  		err = snd_usb_ctl_msg(chip->dev,
  			      usb_sndctrlpipe(chip->dev, 0), 0x24,

  			      USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_OTHER,

  			      value, index + 2, NULL, 0);

  	snd_usb_unlock_shutdown(chip);

  	return err;

  }

  static int snd_audigy2nx_led_put(struct snd_kcontrol *kcontrol,
  				 struct snd_ctl_elem_value *ucontrol)
  {
  	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kcontrol);
  	struct usb_mixer_interface *mixer = list->mixer;
  	int index = kcontrol->private_value & 0xff;

  	unsigned int value = ucontrol->value.integer.value[0];

  	int old_value = kcontrol->private_value >> 8;
  	int err;
  
  	if (value > 1)
  		return -EINVAL;
  	if (value == old_value)
  		return 0;
  	kcontrol->private_value = (value << 8) | index;
  	err = snd_audigy2nx_led_update(mixer, value, index);
  	return err < 0 ? err : 1;
  }
  
  static int snd_audigy2nx_led_resume(struct usb_mixer_elem_list *list)
  {
  	int priv_value = list->kctl->private_value;
  
  	return snd_audigy2nx_led_update(list->mixer, priv_value >> 8,
  					priv_value & 0xff);
  }
  
  /* name and private_value are set dynamically */

  static const struct snd_kcontrol_new snd_audigy2nx_control = {

  	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  	.info = snd_audigy2nx_led_info,
  	.get = snd_audigy2nx_led_get,
  	.put = snd_audigy2nx_led_put,
  };
  
  static const char * const snd_audigy2nx_led_names[] = {
  	"CMSS LED Switch",
  	"Power LED Switch",
  	"Dolby Digital LED Switch",

  };
  
  static int snd_audigy2nx_controls_create(struct usb_mixer_interface *mixer)
  {
  	int i, err;

  	for (i = 0; i < ARRAY_SIZE(snd_audigy2nx_led_names); ++i) {
  		struct snd_kcontrol_new knew;

  		/* USB X-Fi S51 doesn't have a CMSS LED */
  		if ((mixer->chip->usb_id == USB_ID(0x041e, 0x3042)) && i == 0)
  			continue;

  		/* USB X-Fi S51 Pro doesn't have one either */
  		if ((mixer->chip->usb_id == USB_ID(0x041e, 0x30df)) && i == 0)
  			continue;

  		if (i > 1 && /* Live24ext has 2 LEDs only */
  			(mixer->chip->usb_id == USB_ID(0x041e, 0x3040) ||

  			 mixer->chip->usb_id == USB_ID(0x041e, 0x3042) ||

  			 mixer->chip->usb_id == USB_ID(0x041e, 0x30df) ||

  			 mixer->chip->usb_id == USB_ID(0x041e, 0x3048)))
  			break; 

  
  		knew = snd_audigy2nx_control;
  		knew.name = snd_audigy2nx_led_names[i];
  		knew.private_value = (1 << 8) | i; /* LED on as default */
  		err = add_single_ctl_with_resume(mixer, 0,
  						 snd_audigy2nx_led_resume,
  						 &knew, NULL);

  		if (err < 0)
  			return err;
  	}

  	return 0;
  }
  
  static void snd_audigy2nx_proc_read(struct snd_info_entry *entry,
  				    struct snd_info_buffer *buffer)
  {
  	static const struct sb_jack {
  		int unitid;
  		const char *name;
  	}  jacks_audigy2nx[] = {
  		{4,  "dig in "},
  		{7,  "line in"},
  		{19, "spk out"},
  		{20, "hph out"},
  		{-1, NULL}
  	}, jacks_live24ext[] = {
  		{4,  "line in"}, /* &1=Line, &2=Mic*/
  		{3,  "hph out"}, /* headphones */
  		{0,  "RC     "}, /* last command, 6 bytes see rc_config above */
  		{-1, NULL}
  	};
  	const struct sb_jack *jacks;
  	struct usb_mixer_interface *mixer = entry->private_data;
  	int i, err;
  	u8 buf[3];
  
  	snd_iprintf(buffer, "%s jacks
  
  ", mixer->chip->card->shortname);
  	if (mixer->chip->usb_id == USB_ID(0x041e, 0x3020))
  		jacks = jacks_audigy2nx;
  	else if (mixer->chip->usb_id == USB_ID(0x041e, 0x3040) ||
  		 mixer->chip->usb_id == USB_ID(0x041e, 0x3048))
  		jacks = jacks_live24ext;
  	else
  		return;
  
  	for (i = 0; jacks[i].name; ++i) {
  		snd_iprintf(buffer, "%s: ", jacks[i].name);

  		err = snd_usb_lock_shutdown(mixer->chip);
  		if (err < 0)
  			return;
  		err = snd_usb_ctl_msg(mixer->chip->dev,

  				      usb_rcvctrlpipe(mixer->chip->dev, 0),
  				      UAC_GET_MEM, USB_DIR_IN | USB_TYPE_CLASS |
  				      USB_RECIP_INTERFACE, 0,

  				      jacks[i].unitid << 8, buf, 3);

  		snd_usb_unlock_shutdown(mixer->chip);

  		if (err == 3 && (buf[0] == 3 || buf[0] == 6))
  			snd_iprintf(buffer, "%02x %02x
  ", buf[1], buf[2]);
  		else
  			snd_iprintf(buffer, "?
  ");
  	}
  }

  /* EMU0204 */
  static int snd_emu0204_ch_switch_info(struct snd_kcontrol *kcontrol,
  				      struct snd_ctl_elem_info *uinfo)
  {

  	static const char * const texts[2] = {"1/2", "3/4"};

  	return snd_ctl_enum_info(uinfo, 1, ARRAY_SIZE(texts), texts);

  }
  
  static int snd_emu0204_ch_switch_get(struct snd_kcontrol *kcontrol,
  				     struct snd_ctl_elem_value *ucontrol)
  {
  	ucontrol->value.enumerated.item[0] = kcontrol->private_value;
  	return 0;
  }

  static int snd_emu0204_ch_switch_update(struct usb_mixer_interface *mixer,
  					int value)

  {

  	struct snd_usb_audio *chip = mixer->chip;
  	int err;

  	unsigned char buf[2];

  	err = snd_usb_lock_shutdown(chip);
  	if (err < 0)
  		return err;

  
  	buf[0] = 0x01;
  	buf[1] = value ? 0x02 : 0x01;
  	err = snd_usb_ctl_msg(chip->dev,
  		      usb_sndctrlpipe(chip->dev, 0), UAC_SET_CUR,

  		      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
  		      0x0400, 0x0e00, buf, 2);

  	snd_usb_unlock_shutdown(chip);

  	return err;
  }
  
  static int snd_emu0204_ch_switch_put(struct snd_kcontrol *kcontrol,
  				     struct snd_ctl_elem_value *ucontrol)
  {
  	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kcontrol);
  	struct usb_mixer_interface *mixer = list->mixer;
  	unsigned int value = ucontrol->value.enumerated.item[0];
  	int err;
  
  	if (value > 1)
  		return -EINVAL;
  
  	if (value == kcontrol->private_value)
  		return 0;

  	kcontrol->private_value = value;

  	err = snd_emu0204_ch_switch_update(mixer, value);
  	return err < 0 ? err : 1;

  }

  static int snd_emu0204_ch_switch_resume(struct usb_mixer_elem_list *list)
  {
  	return snd_emu0204_ch_switch_update(list->mixer,
  					    list->kctl->private_value);
  }

  static struct snd_kcontrol_new snd_emu0204_control = {
  	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  	.name = "Front Jack Channels",
  	.info = snd_emu0204_ch_switch_info,
  	.get = snd_emu0204_ch_switch_get,
  	.put = snd_emu0204_ch_switch_put,
  	.private_value = 0,

  };
  
  static int snd_emu0204_controls_create(struct usb_mixer_interface *mixer)
  {

  	return add_single_ctl_with_resume(mixer, 0,
  					  snd_emu0204_ch_switch_resume,
  					  &snd_emu0204_control, NULL);

  }

  /* ASUS Xonar U1 / U3 controls */

  static int snd_xonar_u1_switch_get(struct snd_kcontrol *kcontrol,
  				   struct snd_ctl_elem_value *ucontrol)
  {

  	ucontrol->value.integer.value[0] = !!(kcontrol->private_value & 0x02);

  	return 0;
  }

  static int snd_xonar_u1_switch_update(struct usb_mixer_interface *mixer,
  				      unsigned char status)
  {
  	struct snd_usb_audio *chip = mixer->chip;
  	int err;

  	err = snd_usb_lock_shutdown(chip);
  	if (err < 0)
  		return err;
  	err = snd_usb_ctl_msg(chip->dev,

  			      usb_sndctrlpipe(chip->dev, 0), 0x08,
  			      USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_OTHER,
  			      50, 0, &status, 1);

  	snd_usb_unlock_shutdown(chip);

  	return err;
  }

  static int snd_xonar_u1_switch_put(struct snd_kcontrol *kcontrol,
  				   struct snd_ctl_elem_value *ucontrol)
  {

  	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kcontrol);

  	u8 old_status, new_status;

  	int err;

  	old_status = kcontrol->private_value;

  	if (ucontrol->value.integer.value[0])
  		new_status = old_status | 0x02;
  	else
  		new_status = old_status & ~0x02;

  	if (new_status == old_status)
  		return 0;
  
  	kcontrol->private_value = new_status;
  	err = snd_xonar_u1_switch_update(list->mixer, new_status);
  	return err < 0 ? err : 1;
  }
  
  static int snd_xonar_u1_switch_resume(struct usb_mixer_elem_list *list)
  {
  	return snd_xonar_u1_switch_update(list->mixer,
  					  list->kctl->private_value);

  }
  
  static struct snd_kcontrol_new snd_xonar_u1_output_switch = {
  	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  	.name = "Digital Playback Switch",
  	.info = snd_ctl_boolean_mono_info,
  	.get = snd_xonar_u1_switch_get,
  	.put = snd_xonar_u1_switch_put,

  	.private_value = 0x05,

  };
  
  static int snd_xonar_u1_controls_create(struct usb_mixer_interface *mixer)
  {

  	return add_single_ctl_with_resume(mixer, 0,
  					  snd_xonar_u1_switch_resume,
  					  &snd_xonar_u1_output_switch, NULL);

  }

  /* Digidesign Mbox 1 clock source switch (internal/spdif) */
  
  static int snd_mbox1_switch_get(struct snd_kcontrol *kctl,
  				struct snd_ctl_elem_value *ucontrol)
  {
  	ucontrol->value.enumerated.item[0] = kctl->private_value;
  	return 0;
  }

  static int snd_mbox1_switch_update(struct usb_mixer_interface *mixer, int val)

  {

  	struct snd_usb_audio *chip = mixer->chip;

  	int err;

  	unsigned char buff[3];

  	err = snd_usb_lock_shutdown(chip);
  	if (err < 0)
  		return err;

  
  	/* Prepare for magic command to toggle clock source */
  	err = snd_usb_ctl_msg(chip->dev,
  				usb_rcvctrlpipe(chip->dev, 0), 0x81,
  				USB_DIR_IN |
  				USB_TYPE_CLASS |
  				USB_RECIP_INTERFACE, 0x00, 0x500, buff, 1);
  	if (err < 0)
  		goto err;
  	err = snd_usb_ctl_msg(chip->dev,
  				usb_rcvctrlpipe(chip->dev, 0), 0x81,
  				USB_DIR_IN |
  				USB_TYPE_CLASS |
  				USB_RECIP_ENDPOINT, 0x100, 0x81, buff, 3);
  	if (err < 0)
  		goto err;
  
  	/* 2 possibilities:	Internal    -> send sample rate
  	 *			S/PDIF sync -> send zeroes
  	 * NB: Sample rate locked to 48kHz on purpose to
  	 *     prevent user from resetting the sample rate
  	 *     while S/PDIF sync is enabled and confusing
  	 *     this configuration.
  	 */

  	if (val == 0) {

  		buff[0] = 0x80;
  		buff[1] = 0xbb;
  		buff[2] = 0x00;
  	} else {
  		buff[0] = buff[1] = buff[2] = 0x00;
  	}
  
  	/* Send the magic command to toggle the clock source */
  	err = snd_usb_ctl_msg(chip->dev,
  				usb_sndctrlpipe(chip->dev, 0), 0x1,
  				USB_TYPE_CLASS |
  				USB_RECIP_ENDPOINT, 0x100, 0x81, buff, 3);
  	if (err < 0)
  		goto err;
  	err = snd_usb_ctl_msg(chip->dev,
  				usb_rcvctrlpipe(chip->dev, 0), 0x81,
  				USB_DIR_IN |
  				USB_TYPE_CLASS |
  				USB_RECIP_ENDPOINT, 0x100, 0x81, buff, 3);
  	if (err < 0)
  		goto err;
  	err = snd_usb_ctl_msg(chip->dev,
  				usb_rcvctrlpipe(chip->dev, 0), 0x81,
  				USB_DIR_IN |
  				USB_TYPE_CLASS |
  				USB_RECIP_ENDPOINT, 0x100, 0x2, buff, 3);
  	if (err < 0)
  		goto err;

  
  err:

  	snd_usb_unlock_shutdown(chip);

  	return err;
  }
  
  static int snd_mbox1_switch_put(struct snd_kcontrol *kctl,
  				struct snd_ctl_elem_value *ucontrol)
  {
  	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kctl);
  	struct usb_mixer_interface *mixer = list->mixer;
  	int err;
  	bool cur_val, new_val;
  
  	cur_val = kctl->private_value;
  	new_val = ucontrol->value.enumerated.item[0];
  	if (cur_val == new_val)
  		return 0;
  
  	kctl->private_value = new_val;
  	err = snd_mbox1_switch_update(mixer, new_val);

  	return err < 0 ? err : 1;
  }
  
  static int snd_mbox1_switch_info(struct snd_kcontrol *kcontrol,
  				 struct snd_ctl_elem_info *uinfo)
  {
  	static const char *const texts[2] = {
  		"Internal",
  		"S/PDIF"
  	};
  
  	return snd_ctl_enum_info(uinfo, 1, ARRAY_SIZE(texts), texts);
  }

  static int snd_mbox1_switch_resume(struct usb_mixer_elem_list *list)
  {
  	return snd_mbox1_switch_update(list->mixer, list->kctl->private_value);
  }

  static struct snd_kcontrol_new snd_mbox1_switch = {
  	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  	.name = "Clock Source",
  	.index = 0,
  	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
  	.info = snd_mbox1_switch_info,
  	.get = snd_mbox1_switch_get,
  	.put = snd_mbox1_switch_put,
  	.private_value = 0
  };
  
  static int snd_mbox1_create_sync_switch(struct usb_mixer_interface *mixer)
  {

  	return add_single_ctl_with_resume(mixer, 0,
  					  snd_mbox1_switch_resume,
  					  &snd_mbox1_switch, NULL);

  }

  /* Native Instruments device quirks */
  
  #define _MAKE_NI_CONTROL(bRequest,wIndex) ((bRequest) << 16 | (wIndex))

  static int snd_ni_control_init_val(struct usb_mixer_interface *mixer,
  				   struct snd_kcontrol *kctl)

  {

  	struct usb_device *dev = mixer->chip->dev;

  	unsigned int pval = kctl->private_value;
  	u8 value;
  	int err;

  	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
  			      (pval >> 16) & 0xff,
  			      USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
  			      0, pval & 0xffff, &value, 1);
  	if (err < 0) {

  		dev_err(&dev->dev,

  			"unable to issue vendor read request (ret = %d)", err);
  		return err;

  	}

  	kctl->private_value |= ((unsigned int)value << 24);

  	return 0;
  }

  static int snd_nativeinstruments_control_get(struct snd_kcontrol *kcontrol,
  					     struct snd_ctl_elem_value *ucontrol)
  {
  	ucontrol->value.integer.value[0] = kcontrol->private_value >> 24;

  	return 0;
  }

  static int snd_ni_update_cur_val(struct usb_mixer_elem_list *list)
  {
  	struct snd_usb_audio *chip = list->mixer->chip;
  	unsigned int pval = list->kctl->private_value;
  	int err;

  	err = snd_usb_lock_shutdown(chip);
  	if (err < 0)
  		return err;
  	err = usb_control_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0),
  			      (pval >> 16) & 0xff,
  			      USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
  			      pval >> 24, pval & 0xffff, NULL, 0, 1000);
  	snd_usb_unlock_shutdown(chip);

  	return err;
  }

  static int snd_nativeinstruments_control_put(struct snd_kcontrol *kcontrol,
  					     struct snd_ctl_elem_value *ucontrol)
  {

  	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kcontrol);
  	u8 oldval = (kcontrol->private_value >> 24) & 0xff;
  	u8 newval = ucontrol->value.integer.value[0];
  	int err;

  	if (oldval == newval)
  		return 0;

  	kcontrol->private_value &= ~(0xff << 24);

  	kcontrol->private_value |= (unsigned int)newval << 24;

  	err = snd_ni_update_cur_val(list);
  	return err < 0 ? err : 1;

  }
  
  static struct snd_kcontrol_new snd_nativeinstruments_ta6_mixers[] = {
  	{
  		.name = "Direct Thru Channel A",
  		.private_value = _MAKE_NI_CONTROL(0x01, 0x03),
  	},
  	{
  		.name = "Direct Thru Channel B",
  		.private_value = _MAKE_NI_CONTROL(0x01, 0x05),
  	},
  	{
  		.name = "Phono Input Channel A",
  		.private_value = _MAKE_NI_CONTROL(0x02, 0x03),
  	},
  	{
  		.name = "Phono Input Channel B",
  		.private_value = _MAKE_NI_CONTROL(0x02, 0x05),
  	},
  };
  
  static struct snd_kcontrol_new snd_nativeinstruments_ta10_mixers[] = {
  	{
  		.name = "Direct Thru Channel A",
  		.private_value = _MAKE_NI_CONTROL(0x01, 0x03),
  	},
  	{
  		.name = "Direct Thru Channel B",
  		.private_value = _MAKE_NI_CONTROL(0x01, 0x05),
  	},
  	{
  		.name = "Direct Thru Channel C",
  		.private_value = _MAKE_NI_CONTROL(0x01, 0x07),
  	},
  	{
  		.name = "Direct Thru Channel D",
  		.private_value = _MAKE_NI_CONTROL(0x01, 0x09),
  	},
  	{
  		.name = "Phono Input Channel A",
  		.private_value = _MAKE_NI_CONTROL(0x02, 0x03),
  	},
  	{
  		.name = "Phono Input Channel B",
  		.private_value = _MAKE_NI_CONTROL(0x02, 0x05),
  	},
  	{
  		.name = "Phono Input Channel C",
  		.private_value = _MAKE_NI_CONTROL(0x02, 0x07),
  	},
  	{
  		.name = "Phono Input Channel D",
  		.private_value = _MAKE_NI_CONTROL(0x02, 0x09),
  	},
  };
  
  static int snd_nativeinstruments_create_mixer(struct usb_mixer_interface *mixer,
  					      const struct snd_kcontrol_new *kc,
  					      unsigned int count)
  {
  	int i, err = 0;
  	struct snd_kcontrol_new template = {
  		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
  		.get = snd_nativeinstruments_control_get,
  		.put = snd_nativeinstruments_control_put,
  		.info = snd_ctl_boolean_mono_info,
  	};
  
  	for (i = 0; i < count; i++) {

  		struct usb_mixer_elem_list *list;

  
  		template.name = kc[i].name;
  		template.private_value = kc[i].private_value;

  		err = add_single_ctl_with_resume(mixer, 0,
  						 snd_ni_update_cur_val,
  						 &template, &list);

  		if (err < 0)
  			break;

  		snd_ni_control_init_val(mixer, list->kctl);

  	}
  
  	return err;
  }

  /* M-Audio FastTrack Ultra quirks */

  /* FTU Effect switch (also used by C400/C600) */

  static int snd_ftu_eff_switch_info(struct snd_kcontrol *kcontrol,
  					struct snd_ctl_elem_info *uinfo)
  {

  	static const char *const texts[8] = {
  		"Room 1", "Room 2", "Room 3", "Hall 1",
  		"Hall 2", "Plate", "Delay", "Echo"

  	};

  	return snd_ctl_enum_info(uinfo, 1, ARRAY_SIZE(texts), texts);

  }

  static int snd_ftu_eff_switch_init(struct usb_mixer_interface *mixer,
  				   struct snd_kcontrol *kctl)

  {

  	struct usb_device *dev = mixer->chip->dev;
  	unsigned int pval = kctl->private_value;

  	int err;
  	unsigned char value[2];

  
  	value[0] = 0x00;
  	value[1] = 0x00;

  	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
  			      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
  			      pval & 0xff00,
  			      snd_usb_ctrl_intf(mixer->chip) | ((pval & 0xff) << 8),
  			      value, 2);
  	if (err < 0)
  		return err;

  	kctl->private_value |= (unsigned int)value[0] << 24;

  	return 0;
  }

  static int snd_ftu_eff_switch_get(struct snd_kcontrol *kctl,
  					struct snd_ctl_elem_value *ucontrol)
  {
  	ucontrol->value.enumerated.item[0] = kctl->private_value >> 24;
  	return 0;
  }

  static int snd_ftu_eff_switch_update(struct usb_mixer_elem_list *list)
  {
  	struct snd_usb_audio *chip = list->mixer->chip;
  	unsigned int pval = list->kctl->private_value;
  	unsigned char value[2];
  	int err;

  	value[0] = pval >> 24;
  	value[1] = 0;

  	err = snd_usb_lock_shutdown(chip);
  	if (err < 0)
  		return err;
  	err = snd_usb_ctl_msg(chip->dev,
  			      usb_sndctrlpipe(chip->dev, 0),
  			      UAC_SET_CUR,
  			      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
  			      pval & 0xff00,
  			      snd_usb_ctrl_intf(chip) | ((pval & 0xff) << 8),
  			      value, 2);
  	snd_usb_unlock_shutdown(chip);

  	return err;

  }
  
  static int snd_ftu_eff_switch_put(struct snd_kcontrol *kctl,
  					struct snd_ctl_elem_value *ucontrol)
  {

  	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kctl);
  	unsigned int pval = list->kctl->private_value;
  	int cur_val, err, new_val;

  	cur_val = pval >> 24;

  	new_val = ucontrol->value.enumerated.item[0];

  	if (cur_val == new_val)
  		return 0;

  	kctl->private_value &= ~(0xff << 24);
  	kctl->private_value |= new_val << 24;
  	err = snd_ftu_eff_switch_update(list);
  	return err < 0 ? err : 1;

  }

  static int snd_ftu_create_effect_switch(struct usb_mixer_interface *mixer,
  	int validx, int bUnitID)

  {
  	static struct snd_kcontrol_new template = {
  		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  		.name = "Effect Program Switch",
  		.index = 0,
  		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
  		.info = snd_ftu_eff_switch_info,
  		.get = snd_ftu_eff_switch_get,
  		.put = snd_ftu_eff_switch_put
  	};

  	struct usb_mixer_elem_list *list;

  	int err;

  	err = add_single_ctl_with_resume(mixer, bUnitID,
  					 snd_ftu_eff_switch_update,
  					 &template, &list);

  	if (err < 0)
  		return err;

  	list->kctl->private_value = (validx << 8) | bUnitID;
  	snd_ftu_eff_switch_init(mixer, list->kctl);

  	return 0;
  }

  /* Create volume controls for FTU devices*/
  static int snd_ftu_create_volume_ctls(struct usb_mixer_interface *mixer)

  {
  	char name[64];

  	unsigned int control, cmask;

  	int in, out, err;

  	const unsigned int id = 5;
  	const int val_type = USB_MIXER_S16;

  	for (out = 0; out < 8; out++) {

  		control = out + 1;

  		for (in = 0; in < 8; in++) {

  			cmask = 1 << in;

  			snprintf(name, sizeof(name),

  				"AIn%d - Out%d Capture Volume",
  				in  + 1, out + 1);
  			err = snd_create_std_mono_ctl(mixer, id, control,
  							cmask, val_type, name,

  							&snd_usb_mixer_vol_tlv);

  			if (err < 0)
  				return err;
  		}

  		for (in = 8; in < 16; in++) {

  			cmask = 1 << in;

  			snprintf(name, sizeof(name),

  				"DIn%d - Out%d Playback Volume",
  				in - 7, out + 1);
  			err = snd_create_std_mono_ctl(mixer, id, control,
  							cmask, val_type, name,

  							&snd_usb_mixer_vol_tlv);

  			if (err < 0)
  				return err;
  		}
  	}
  
  	return 0;
  }

  /* This control needs a volume quirk, see mixer.c */
  static int snd_ftu_create_effect_volume_ctl(struct usb_mixer_interface *mixer)
  {
  	static const char name[] = "Effect Volume";
  	const unsigned int id = 6;
  	const int val_type = USB_MIXER_U8;
  	const unsigned int control = 2;
  	const unsigned int cmask = 0;
  
  	return snd_create_std_mono_ctl(mixer, id, control, cmask, val_type,
  					name, snd_usb_mixer_vol_tlv);
  }
  
  /* This control needs a volume quirk, see mixer.c */
  static int snd_ftu_create_effect_duration_ctl(struct usb_mixer_interface *mixer)
  {
  	static const char name[] = "Effect Duration";
  	const unsigned int id = 6;
  	const int val_type = USB_MIXER_S16;
  	const unsigned int control = 3;
  	const unsigned int cmask = 0;
  
  	return snd_create_std_mono_ctl(mixer, id, control, cmask, val_type,
  					name, snd_usb_mixer_vol_tlv);
  }
  
  /* This control needs a volume quirk, see mixer.c */
  static int snd_ftu_create_effect_feedback_ctl(struct usb_mixer_interface *mixer)
  {
  	static const char name[] = "Effect Feedback Volume";
  	const unsigned int id = 6;
  	const int val_type = USB_MIXER_U8;
  	const unsigned int control = 4;
  	const unsigned int cmask = 0;
  
  	return snd_create_std_mono_ctl(mixer, id, control, cmask, val_type,
  					name, NULL);
  }
  
  static int snd_ftu_create_effect_return_ctls(struct usb_mixer_interface *mixer)
  {
  	unsigned int cmask;
  	int err, ch;
  	char name[48];
  
  	const unsigned int id = 7;
  	const int val_type = USB_MIXER_S16;
  	const unsigned int control = 7;
  
  	for (ch = 0; ch < 4; ++ch) {
  		cmask = 1 << ch;
  		snprintf(name, sizeof(name),
  			"Effect Return %d Volume", ch + 1);
  		err = snd_create_std_mono_ctl(mixer, id, control,
  						cmask, val_type, name,
  						snd_usb_mixer_vol_tlv);
  		if (err < 0)
  			return err;
  	}
  
  	return 0;
  }
  
  static int snd_ftu_create_effect_send_ctls(struct usb_mixer_interface *mixer)
  {
  	unsigned int  cmask;
  	int err, ch;
  	char name[48];
  
  	const unsigned int id = 5;
  	const int val_type = USB_MIXER_S16;
  	const unsigned int control = 9;
  
  	for (ch = 0; ch < 8; ++ch) {
  		cmask = 1 << ch;
  		snprintf(name, sizeof(name),
  			"Effect Send AIn%d Volume", ch + 1);
  		err = snd_create_std_mono_ctl(mixer, id, control, cmask,
  						val_type, name,
  						snd_usb_mixer_vol_tlv);
  		if (err < 0)
  			return err;
  	}
  	for (ch = 8; ch < 16; ++ch) {
  		cmask = 1 << ch;
  		snprintf(name, sizeof(name),
  			"Effect Send DIn%d Volume", ch - 7);
  		err = snd_create_std_mono_ctl(mixer, id, control, cmask,
  						val_type, name,
  						snd_usb_mixer_vol_tlv);
  		if (err < 0)
  			return err;
  	}
  	return 0;
  }

  static int snd_ftu_create_mixer(struct usb_mixer_interface *mixer)

  {

  	int err;

  	err = snd_ftu_create_volume_ctls(mixer);

  	if (err < 0)
  		return err;

  	err = snd_ftu_create_effect_switch(mixer, 1, 6);

  	if (err < 0)
  		return err;

  	err = snd_ftu_create_effect_volume_ctl(mixer);
  	if (err < 0)
  		return err;
  
  	err = snd_ftu_create_effect_duration_ctl(mixer);
  	if (err < 0)
  		return err;
  
  	err = snd_ftu_create_effect_feedback_ctl(mixer);
  	if (err < 0)
  		return err;
  
  	err = snd_ftu_create_effect_return_ctls(mixer);
  	if (err < 0)
  		return err;
  
  	err = snd_ftu_create_effect_send_ctls(mixer);
  	if (err < 0)
  		return err;

  	return 0;

  }

  void snd_emuusb_set_samplerate(struct snd_usb_audio *chip,
  			       unsigned char samplerate_id)
  {
  	struct usb_mixer_interface *mixer;
  	struct usb_mixer_elem_info *cval;

  	int unitid = 12; /* SampleRate ExtensionUnit ID */

  
  	list_for_each_entry(mixer, &chip->mixer_list, list) {

  		if (mixer->id_elems[unitid]) {
  			cval = mixer_elem_list_to_info(mixer->id_elems[unitid]);

  			snd_usb_mixer_set_ctl_value(cval, UAC_SET_CUR,
  						    cval->control << 8,
  						    samplerate_id);
  			snd_usb_mixer_notify_id(mixer, unitid);

  			break;

  		}

  	}
  }

  /* M-Audio Fast Track C400/C600 */
  /* C400/C600 volume controls, this control needs a volume quirk, see mixer.c */

  static int snd_c400_create_vol_ctls(struct usb_mixer_interface *mixer)
  {
  	char name[64];
  	unsigned int cmask, offset;
  	int out, chan, err;

  	int num_outs = 0;
  	int num_ins = 0;

  
  	const unsigned int id = 0x40;
  	const int val_type = USB_MIXER_S16;
  	const int control = 1;

  	switch (mixer->chip->usb_id) {
  	case USB_ID(0x0763, 0x2030):
  		num_outs = 6;
  		num_ins = 4;
  		break;
  	case USB_ID(0x0763, 0x2031):
  		num_outs = 8;
  		num_ins = 6;
  		break;
  	}
  
  	for (chan = 0; chan < num_outs + num_ins; chan++) {
  		for (out = 0; out < num_outs; out++) {
  			if (chan < num_outs) {

  				snprintf(name, sizeof(name),
  					"PCM%d-Out%d Playback Volume",
  					chan + 1, out + 1);
  			} else {
  				snprintf(name, sizeof(name),
  					"In%d-Out%d Playback Volume",

  					chan - num_outs + 1, out + 1);

  			}
  
  			cmask = (out == 0) ? 0 : 1 << (out - 1);

  			offset = chan * num_outs;

  			err = snd_create_std_mono_ctl_offset(mixer, id, control,
  						cmask, val_type, offset, name,
  						&snd_usb_mixer_vol_tlv);
  			if (err < 0)
  				return err;
  		}
  	}
  
  	return 0;
  }
  
  /* This control needs a volume quirk, see mixer.c */
  static int snd_c400_create_effect_volume_ctl(struct usb_mixer_interface *mixer)
  {
  	static const char name[] = "Effect Volume";
  	const unsigned int id = 0x43;
  	const int val_type = USB_MIXER_U8;
  	const unsigned int control = 3;
  	const unsigned int cmask = 0;
  
  	return snd_create_std_mono_ctl(mixer, id, control, cmask, val_type,
  					name, snd_usb_mixer_vol_tlv);
  }
  
  /* This control needs a volume quirk, see mixer.c */
  static int snd_c400_create_effect_duration_ctl(struct usb_mixer_interface *mixer)
  {
  	static const char name[] = "Effect Duration";
  	const unsigned int id = 0x43;
  	const int val_type = USB_MIXER_S16;
  	const unsigned int control = 4;
  	const unsigned int cmask = 0;
  
  	return snd_create_std_mono_ctl(mixer, id, control, cmask, val_type,
  					name, snd_usb_mixer_vol_tlv);
  }
  
  /* This control needs a volume quirk, see mixer.c */
  static int snd_c400_create_effect_feedback_ctl(struct usb_mixer_interface *mixer)
  {
  	static const char name[] = "Effect Feedback Volume";
  	const unsigned int id = 0x43;
  	const int val_type = USB_MIXER_U8;
  	const unsigned int control = 5;
  	const unsigned int cmask = 0;
  
  	return snd_create_std_mono_ctl(mixer, id, control, cmask, val_type,
  					name, NULL);
  }
  
  static int snd_c400_create_effect_vol_ctls(struct usb_mixer_interface *mixer)
  {
  	char name[64];
  	unsigned int cmask;
  	int chan, err;

  	int num_outs = 0;
  	int num_ins = 0;

  
  	const unsigned int id = 0x42;
  	const int val_type = USB_MIXER_S16;
  	const int control = 1;

  	switch (mixer->chip->usb_id) {
  	case USB_ID(0x0763, 0x2030):
  		num_outs = 6;
  		num_ins = 4;
  		break;
  	case USB_ID(0x0763, 0x2031):
  		num_outs = 8;
  		num_ins = 6;
  		break;
  	}
  
  	for (chan = 0; chan < num_outs + num_ins; chan++) {
  		if (chan < num_outs) {

  			snprintf(name, sizeof(name),
  				"Effect Send DOut%d",
  				chan + 1);
  		} else {
  			snprintf(name, sizeof(name),
  				"Effect Send AIn%d",

  				chan - num_outs + 1);

  		}
  
  		cmask = (chan == 0) ? 0 : 1 << (chan - 1);
  		err = snd_create_std_mono_ctl(mixer, id, control,
  						cmask, val_type, name,
  						&snd_usb_mixer_vol_tlv);
  		if (err < 0)
  			return err;
  	}
  
  	return 0;
  }
  
  static int snd_c400_create_effect_ret_vol_ctls(struct usb_mixer_interface *mixer)
  {
  	char name[64];
  	unsigned int cmask;
  	int chan, err;

  	int num_outs = 0;
  	int offset = 0;

  
  	const unsigned int id = 0x40;
  	const int val_type = USB_MIXER_S16;
  	const int control = 1;

  	switch (mixer->chip->usb_id) {
  	case USB_ID(0x0763, 0x2030):
  		num_outs = 6;
  		offset = 0x3c;
  		/* { 0x3c, 0x43, 0x3e, 0x45, 0x40, 0x47 } */
  		break;
  	case USB_ID(0x0763, 0x2031):
  		num_outs = 8;
  		offset = 0x70;
  		/* { 0x70, 0x79, 0x72, 0x7b, 0x74, 0x7d, 0x76, 0x7f } */
  		break;
  	}
  
  	for (chan = 0; chan < num_outs; chan++) {

  		snprintf(name, sizeof(name),
  			"Effect Return %d",
  			chan + 1);

  		cmask = (chan == 0) ? 0 :
  			1 << (chan + (chan % 2) * num_outs - 1);

  		err = snd_create_std_mono_ctl_offset(mixer, id, control,
  						cmask, val_type, offset, name,
  						&snd_usb_mixer_vol_tlv);
  		if (err < 0)
  			return err;
  	}
  
  	return 0;
  }
  
  static int snd_c400_create_mixer(struct usb_mixer_interface *mixer)
  {
  	int err;
  
  	err = snd_c400_create_vol_ctls(mixer);
  	if (err < 0)
  		return err;
  
  	err = snd_c400_create_effect_vol_ctls(mixer);
  	if (err < 0)
  		return err;
  
  	err = snd_c400_create_effect_ret_vol_ctls(mixer);
  	if (err < 0)
  		return err;
  
  	err = snd_ftu_create_effect_switch(mixer, 2, 0x43);
  	if (err < 0)
  		return err;
  
  	err = snd_c400_create_effect_volume_ctl(mixer);
  	if (err < 0)
  		return err;
  
  	err = snd_c400_create_effect_duration_ctl(mixer);
  	if (err < 0)
  		return err;
  
  	err = snd_c400_create_effect_feedback_ctl(mixer);
  	if (err < 0)
  		return err;
  
  	return 0;
  }

  /*
   * The mixer units for Ebox-44 are corrupt, and even where they
   * are valid they presents mono controls as L and R channels of
   * stereo. So we provide a good mixer here.
   */

  static struct std_mono_table ebox44_table[] = {

  	{
  		.unitid = 4,
  		.control = 1,
  		.cmask = 0x0,
  		.val_type = USB_MIXER_INV_BOOLEAN,
  		.name = "Headphone Playback Switch"
  	},
  	{
  		.unitid = 4,
  		.control = 2,
  		.cmask = 0x1,
  		.val_type = USB_MIXER_S16,
  		.name = "Headphone A Mix Playback Volume"
  	},
  	{
  		.unitid = 4,
  		.control = 2,
  		.cmask = 0x2,
  		.val_type = USB_MIXER_S16,
  		.name = "Headphone B Mix Playback Volume"
  	},

  	{
  		.unitid = 7,
  		.control = 1,
  		.cmask = 0x0,
  		.val_type = USB_MIXER_INV_BOOLEAN,
  		.name = "Output Playback Switch"
  	},
  	{
  		.unitid = 7,
  		.control = 2,
  		.cmask = 0x1,
  		.val_type = USB_MIXER_S16,
  		.name = "Output A Playback Volume"
  	},
  	{
  		.unitid = 7,
  		.control = 2,
  		.cmask = 0x2,
  		.val_type = USB_MIXER_S16,
  		.name = "Output B Playback Volume"
  	},

  	{
  		.unitid = 10,
  		.control = 1,
  		.cmask = 0x0,
  		.val_type = USB_MIXER_INV_BOOLEAN,
  		.name = "Input Capture Switch"
  	},
  	{
  		.unitid = 10,
  		.control = 2,
  		.cmask = 0x1,
  		.val_type = USB_MIXER_S16,
  		.name = "Input A Capture Volume"
  	},
  	{
  		.unitid = 10,
  		.control = 2,
  		.cmask = 0x2,
  		.val_type = USB_MIXER_S16,
  		.name = "Input B Capture Volume"
  	},

  	{}

  };

  /* Audio Advantage Micro II findings:
   *
   * Mapping spdif AES bits to vendor register.bit:
   * AES0: [0 0 0 0 2.3 2.2 2.1 2.0] - default 0x00
   * AES1: [3.3 3.2.3.1.3.0 2.7 2.6 2.5 2.4] - default: 0x01
   * AES2: [0 0 0 0 0 0 0 0]
   * AES3: [0 0 0 0 0 0 x 0] - 'x' bit is set basing on standard usb request
   *                           (UAC_EP_CS_ATTR_SAMPLE_RATE) for Audio Devices
   *
   * power on values:
   * r2: 0x10
   * r3: 0x20 (b7 is zeroed just before playback (except IEC61937) and set
   *           just after it to 0xa0, presumably it disables/mutes some analog
   *           parts when there is no audio.)
   * r9: 0x28
   *
   * Optical transmitter on/off:
   * vendor register.bit: 9.1
   * 0 - on (0x28 register value)
   * 1 - off (0x2a register value)
   *
   */
  static int snd_microii_spdif_info(struct snd_kcontrol *kcontrol,
  	struct snd_ctl_elem_info *uinfo)
  {
  	uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
  	uinfo->count = 1;
  	return 0;
  }
  
  static int snd_microii_spdif_default_get(struct snd_kcontrol *kcontrol,
  	struct snd_ctl_elem_value *ucontrol)
  {

  	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kcontrol);
  	struct snd_usb_audio *chip = list->mixer->chip;

  	int err;
  	struct usb_interface *iface;
  	struct usb_host_interface *alts;
  	unsigned int ep;
  	unsigned char data[3];
  	int rate;

  	err = snd_usb_lock_shutdown(chip);
  	if (err < 0)
  		return err;

  	ucontrol->value.iec958.status[0] = kcontrol->private_value & 0xff;
  	ucontrol->value.iec958.status[1] = (kcontrol->private_value >> 8) & 0xff;
  	ucontrol->value.iec958.status[2] = 0x00;
  
  	/* use known values for that card: interface#1 altsetting#1 */

  	iface = usb_ifnum_to_if(chip->dev, 1);

  	if (!iface || iface->num_altsetting < 2)
  		return -EINVAL;

  	alts = &iface->altsetting[1];

  	if (get_iface_desc(alts)->bNumEndpoints < 1)
  		return -EINVAL;

  	ep = get_endpoint(alts, 0)->bEndpointAddress;

  	err = snd_usb_ctl_msg(chip->dev,
  			usb_rcvctrlpipe(chip->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)
  		goto end;
  
  	rate = data[0] | (data[1] << 8) | (data[2] << 16);
  	ucontrol->value.iec958.status[3] = (rate == 48000) ?
  			IEC958_AES3_CON_FS_48000 : IEC958_AES3_CON_FS_44100;
  
  	err = 0;

   end:

  	snd_usb_unlock_shutdown(chip);

  	return err;
  }

  static int snd_microii_spdif_default_update(struct usb_mixer_elem_list *list)

  {

  	struct snd_usb_audio *chip = list->mixer->chip;
  	unsigned int pval = list->kctl->private_value;

  	u8 reg;

  	int err;

  	err = snd_usb_lock_shutdown(chip);
  	if (err < 0)
  		return err;

  	reg = ((pval >> 4) & 0xf0) | (pval & 0x0f);
  	err = snd_usb_ctl_msg(chip->dev,
  			usb_sndctrlpipe(chip->dev, 0),

  			UAC_SET_CUR,
  			USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_OTHER,
  			reg,
  			2,
  			NULL,
  			0);
  	if (err < 0)
  		goto end;

  	reg = (pval & IEC958_AES0_NONAUDIO) ? 0xa0 : 0x20;
  	reg |= (pval >> 12) & 0x0f;
  	err = snd_usb_ctl_msg(chip->dev,
  			usb_sndctrlpipe(chip->dev, 0),

  			UAC_SET_CUR,
  			USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_OTHER,
  			reg,
  			3,
  			NULL,
  			0);
  	if (err < 0)
  		goto end;

   end:

  	snd_usb_unlock_shutdown(chip);

  	return err;
  }
  
  static int snd_microii_spdif_default_put(struct snd_kcontrol *kcontrol,
  	struct snd_ctl_elem_value *ucontrol)
  {
  	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kcontrol);
  	unsigned int pval, pval_old;
  	int err;
  
  	pval = pval_old = kcontrol->private_value;
  	pval &= 0xfffff0f0;
  	pval |= (ucontrol->value.iec958.status[1] & 0x0f) << 8;
  	pval |= (ucontrol->value.iec958.status[0] & 0x0f);
  
  	pval &= 0xffff0fff;
  	pval |= (ucontrol->value.iec958.status[1] & 0xf0) << 8;

  
  	/* The frequency bits in AES3 cannot be set via register access. */
  
  	/* Silently ignore any bits from the request that cannot be set. */

  	if (pval == pval_old)
  		return 0;
  
  	kcontrol->private_value = pval;
  	err = snd_microii_spdif_default_update(list);
  	return err < 0 ? err : 1;

  }
  
  static int snd_microii_spdif_mask_get(struct snd_kcontrol *kcontrol,
  	struct snd_ctl_elem_value *ucontrol)
  {
  	ucontrol->value.iec958.status[0] = 0x0f;
  	ucontrol->value.iec958.status[1] = 0xff;
  	ucontrol->value.iec958.status[2] = 0x00;
  	ucontrol->value.iec958.status[3] = 0x00;
  
  	return 0;
  }
  
  static int snd_microii_spdif_switch_get(struct snd_kcontrol *kcontrol,
  	struct snd_ctl_elem_value *ucontrol)
  {
  	ucontrol->value.integer.value[0] = !(kcontrol->private_value & 0x02);
  
  	return 0;
  }

  static int snd_microii_spdif_switch_update(struct usb_mixer_elem_list *list)

  {

  	struct snd_usb_audio *chip = list->mixer->chip;
  	u8 reg = list->kctl->private_value;

  	int err;

  	err = snd_usb_lock_shutdown(chip);
  	if (err < 0)
  		return err;

  
  	err = snd_usb_ctl_msg(chip->dev,
  			usb_sndctrlpipe(chip->dev, 0),

  			UAC_SET_CUR,
  			USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_OTHER,
  			reg,
  			9,
  			NULL,
  			0);

  	snd_usb_unlock_shutdown(chip);

  	return err;
  }

  static int snd_microii_spdif_switch_put(struct snd_kcontrol *kcontrol,
  	struct snd_ctl_elem_value *ucontrol)
  {
  	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kcontrol);
  	u8 reg;
  	int err;
  
  	reg = ucontrol->value.integer.value[0] ? 0x28 : 0x2a;
  	if (reg != list->kctl->private_value)
  		return 0;
  
  	kcontrol->private_value = reg;
  	err = snd_microii_spdif_switch_update(list);
  	return err < 0 ? err : 1;
  }

  static struct snd_kcontrol_new snd_microii_mixer_spdif[] = {
  	{
  		.iface =    SNDRV_CTL_ELEM_IFACE_PCM,
  		.name =     SNDRV_CTL_NAME_IEC958("", PLAYBACK, DEFAULT),
  		.info =     snd_microii_spdif_info,
  		.get =      snd_microii_spdif_default_get,
  		.put =      snd_microii_spdif_default_put,
  		.private_value = 0x00000100UL,/* reset value */
  	},
  	{
  		.access =   SNDRV_CTL_ELEM_ACCESS_READ,
  		.iface =    SNDRV_CTL_ELEM_IFACE_PCM,
  		.name =     SNDRV_CTL_NAME_IEC958("", PLAYBACK, MASK),
  		.info =     snd_microii_spdif_info,
  		.get =      snd_microii_spdif_mask_get,
  	},
  	{
  		.iface =    SNDRV_CTL_ELEM_IFACE_MIXER,
  		.name =     SNDRV_CTL_NAME_IEC958("", PLAYBACK, SWITCH),
  		.info =     snd_ctl_boolean_mono_info,
  		.get =      snd_microii_spdif_switch_get,
  		.put =      snd_microii_spdif_switch_put,
  		.private_value = 0x00000028UL,/* reset value */
  	}
  };
  
  static int snd_microii_controls_create(struct usb_mixer_interface *mixer)
  {
  	int err, i;

  	static usb_mixer_elem_resume_func_t resume_funcs[] = {
  		snd_microii_spdif_default_update,
  		NULL,
  		snd_microii_spdif_switch_update
  	};

  
  	for (i = 0; i < ARRAY_SIZE(snd_microii_mixer_spdif); ++i) {

  		err = add_single_ctl_with_resume(mixer, 0,
  						 resume_funcs[i],
  						 &snd_microii_mixer_spdif[i],
  						 NULL);

  		if (err < 0)
  			return err;
  	}

  	return 0;

  }

  /* Creative Sound Blaster E1 */
  
  static int snd_soundblaster_e1_switch_get(struct snd_kcontrol *kcontrol,
  					  struct snd_ctl_elem_value *ucontrol)
  {
  	ucontrol->value.integer.value[0] = kcontrol->private_value;
  	return 0;
  }
  
  static int snd_soundblaster_e1_switch_update(struct usb_mixer_interface *mixer,
  					     unsigned char state)
  {
  	struct snd_usb_audio *chip = mixer->chip;
  	int err;
  	unsigned char buff[2];
  
  	buff[0] = 0x02;
  	buff[1] = state ? 0x02 : 0x00;
  
  	err = snd_usb_lock_shutdown(chip);
  	if (err < 0)
  		return err;
  	err = snd_usb_ctl_msg(chip->dev,
  			usb_sndctrlpipe(chip->dev, 0), HID_REQ_SET_REPORT,
  			USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
  			0x0202, 3, buff, 2);
  	snd_usb_unlock_shutdown(chip);
  	return err;
  }
  
  static int snd_soundblaster_e1_switch_put(struct snd_kcontrol *kcontrol,
  					  struct snd_ctl_elem_value *ucontrol)
  {
  	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kcontrol);
  	unsigned char value = !!ucontrol->value.integer.value[0];
  	int err;
  
  	if (kcontrol->private_value == value)
  		return 0;
  	kcontrol->private_value = value;
  	err = snd_soundblaster_e1_switch_update(list->mixer, value);
  	return err < 0 ? err : 1;
  }
  
  static int snd_soundblaster_e1_switch_resume(struct usb_mixer_elem_list *list)
  {
  	return snd_soundblaster_e1_switch_update(list->mixer,
  						 list->kctl->private_value);
  }
  
  static int snd_soundblaster_e1_switch_info(struct snd_kcontrol *kcontrol,
  					   struct snd_ctl_elem_info *uinfo)
  {
  	static const char *const texts[2] = {
  		"Mic", "Aux"
  	};
  
  	return snd_ctl_enum_info(uinfo, 1, ARRAY_SIZE(texts), texts);
  }
  
  static struct snd_kcontrol_new snd_soundblaster_e1_input_switch = {
  	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  	.name = "Input Source",
  	.info = snd_soundblaster_e1_switch_info,
  	.get = snd_soundblaster_e1_switch_get,
  	.put = snd_soundblaster_e1_switch_put,
  	.private_value = 0,
  };
  
  static int snd_soundblaster_e1_switch_create(struct usb_mixer_interface *mixer)
  {
  	return add_single_ctl_with_resume(mixer, 0,
  					  snd_soundblaster_e1_switch_resume,
  					  &snd_soundblaster_e1_input_switch,
  					  NULL);
  }

  static void dell_dock_init_vol(struct snd_usb_audio *chip, int ch, int id)
  {
  	u16 buf = 0;
  
  	snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0), UAC_SET_CUR,
  			USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
  			ch, snd_usb_ctrl_intf(chip) | (id << 8),
  			&buf, 2);
  }
  
  static int dell_dock_mixer_init(struct usb_mixer_interface *mixer)
  {
  	/* fix to 0dB playback volumes */
  	dell_dock_init_vol(mixer->chip, 1, 16);
  	dell_dock_init_vol(mixer->chip, 2, 16);
  	dell_dock_init_vol(mixer->chip, 1, 19);
  	dell_dock_init_vol(mixer->chip, 2, 19);
  	return 0;
  }

  /* RME Class Compliant device quirks */
  
  #define SND_RME_GET_STATUS1			23
  #define SND_RME_GET_CURRENT_FREQ		17
  #define SND_RME_CLK_SYSTEM_SHIFT		16
  #define SND_RME_CLK_SYSTEM_MASK			0x1f
  #define SND_RME_CLK_AES_SHIFT			8
  #define SND_RME_CLK_SPDIF_SHIFT			12
  #define SND_RME_CLK_AES_SPDIF_MASK		0xf
  #define SND_RME_CLK_SYNC_SHIFT			6
  #define SND_RME_CLK_SYNC_MASK			0x3
  #define SND_RME_CLK_FREQMUL_SHIFT		18
  #define SND_RME_CLK_FREQMUL_MASK		0x7
  #define SND_RME_CLK_SYSTEM(x) \
  	((x >> SND_RME_CLK_SYSTEM_SHIFT) & SND_RME_CLK_SYSTEM_MASK)
  #define SND_RME_CLK_AES(x) \
  	((x >> SND_RME_CLK_AES_SHIFT) & SND_RME_CLK_AES_SPDIF_MASK)
  #define SND_RME_CLK_SPDIF(x) \
  	((x >> SND_RME_CLK_SPDIF_SHIFT) & SND_RME_CLK_AES_SPDIF_MASK)
  #define SND_RME_CLK_SYNC(x) \
  	((x >> SND_RME_CLK_SYNC_SHIFT) & SND_RME_CLK_SYNC_MASK)
  #define SND_RME_CLK_FREQMUL(x) \
  	((x >> SND_RME_CLK_FREQMUL_SHIFT) & SND_RME_CLK_FREQMUL_MASK)
  #define SND_RME_CLK_AES_LOCK			0x1
  #define SND_RME_CLK_AES_SYNC			0x4
  #define SND_RME_CLK_SPDIF_LOCK			0x2
  #define SND_RME_CLK_SPDIF_SYNC			0x8
  #define SND_RME_SPDIF_IF_SHIFT			4
  #define SND_RME_SPDIF_FORMAT_SHIFT		5
  #define SND_RME_BINARY_MASK			0x1
  #define SND_RME_SPDIF_IF(x) \
  	((x >> SND_RME_SPDIF_IF_SHIFT) & SND_RME_BINARY_MASK)
  #define SND_RME_SPDIF_FORMAT(x) \
  	((x >> SND_RME_SPDIF_FORMAT_SHIFT) & SND_RME_BINARY_MASK)
  
  static const u32 snd_rme_rate_table[] = {
  	32000, 44100, 48000, 50000,
  	64000, 88200, 96000, 100000,
  	128000, 176400, 192000, 200000,
  	256000,	352800, 384000, 400000,
  	512000, 705600, 768000, 800000
  };
  /* maximum number of items for AES and S/PDIF rates for above table */
  #define SND_RME_RATE_IDX_AES_SPDIF_NUM		12
  
  enum snd_rme_domain {
  	SND_RME_DOMAIN_SYSTEM,
  	SND_RME_DOMAIN_AES,
  	SND_RME_DOMAIN_SPDIF
  };
  
  enum snd_rme_clock_status {
  	SND_RME_CLOCK_NOLOCK,
  	SND_RME_CLOCK_LOCK,
  	SND_RME_CLOCK_SYNC
  };
  
  static int snd_rme_read_value(struct snd_usb_audio *chip,
  			      unsigned int item,
  			      u32 *value)
  {
  	struct usb_device *dev = chip->dev;
  	int err;
  
  	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
  			      item,
  			      USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
  			      0, 0,
  			      value, sizeof(*value));
  	if (err < 0)
  		dev_err(&dev->dev,
  			"unable to issue vendor read request %d (ret = %d)",
  			item, err);
  	return err;
  }
  
  static int snd_rme_get_status1(struct snd_kcontrol *kcontrol,
  			       u32 *status1)
  {
  	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kcontrol);
  	struct snd_usb_audio *chip = list->mixer->chip;
  	int err;
  
  	err = snd_usb_lock_shutdown(chip);
  	if (err < 0)
  		return err;
  	err = snd_rme_read_value(chip, SND_RME_GET_STATUS1, status1);
  	snd_usb_unlock_shutdown(chip);
  	return err;
  }
  
  static int snd_rme_rate_get(struct snd_kcontrol *kcontrol,
  			    struct snd_ctl_elem_value *ucontrol)
  {
  	u32 status1;
  	u32 rate = 0;
  	int idx;
  	int err;
  
  	err = snd_rme_get_status1(kcontrol, &status1);
  	if (err < 0)
  		return err;
  	switch (kcontrol->private_value) {
  	case SND_RME_DOMAIN_SYSTEM:
  		idx = SND_RME_CLK_SYSTEM(status1);
  		if (idx < ARRAY_SIZE(snd_rme_rate_table))
  			rate = snd_rme_rate_table[idx];
  		break;
  	case SND_RME_DOMAIN_AES:
  		idx = SND_RME_CLK_AES(status1);
  		if (idx < SND_RME_RATE_IDX_AES_SPDIF_NUM)
  			rate = snd_rme_rate_table[idx];
  		break;
  	case SND_RME_DOMAIN_SPDIF:
  		idx = SND_RME_CLK_SPDIF(status1);
  		if (idx < SND_RME_RATE_IDX_AES_SPDIF_NUM)
  			rate = snd_rme_rate_table[idx];
  		break;
  	default:
  		return -EINVAL;
  	}
  	ucontrol->value.integer.value[0] = rate;
  	return 0;
  }
  
  static int snd_rme_sync_state_get(struct snd_kcontrol *kcontrol,
  				  struct snd_ctl_elem_value *ucontrol)
  {
  	u32 status1;
  	int idx = SND_RME_CLOCK_NOLOCK;
  	int err;
  
  	err = snd_rme_get_status1(kcontrol, &status1);
  	if (err < 0)
  		return err;
  	switch (kcontrol->private_value) {
  	case SND_RME_DOMAIN_AES:  /* AES */
  		if (status1 & SND_RME_CLK_AES_SYNC)
  			idx = SND_RME_CLOCK_SYNC;
  		else if (status1 & SND_RME_CLK_AES_LOCK)
  			idx = SND_RME_CLOCK_LOCK;
  		break;
  	case SND_RME_DOMAIN_SPDIF:  /* SPDIF */
  		if (status1 & SND_RME_CLK_SPDIF_SYNC)
  			idx = SND_RME_CLOCK_SYNC;
  		else if (status1 & SND_RME_CLK_SPDIF_LOCK)
  			idx = SND_RME_CLOCK_LOCK;
  		break;
  	default:
  		return -EINVAL;
  	}
  	ucontrol->value.enumerated.item[0] = idx;
  	return 0;
  }
  
  static int snd_rme_spdif_if_get(struct snd_kcontrol *kcontrol,
  				struct snd_ctl_elem_value *ucontrol)
  {
  	u32 status1;
  	int err;
  
  	err = snd_rme_get_status1(kcontrol, &status1);
  	if (err < 0)
  		return err;
  	ucontrol->value.enumerated.item[0] = SND_RME_SPDIF_IF(status1);
  	return 0;
  }
  
  static int snd_rme_spdif_format_get(struct snd_kcontrol *kcontrol,
  				    struct snd_ctl_elem_value *ucontrol)
  {
  	u32 status1;
  	int err;
  
  	err = snd_rme_get_status1(kcontrol, &status1);
  	if (err < 0)
  		return err;
  	ucontrol->value.enumerated.item[0] = SND_RME_SPDIF_FORMAT(status1);
  	return 0;
  }
  
  static int snd_rme_sync_source_get(struct snd_kcontrol *kcontrol,
  				   struct snd_ctl_elem_value *ucontrol)
  {
  	u32 status1;
  	int err;
  
  	err = snd_rme_get_status1(kcontrol, &status1);
  	if (err < 0)
  		return err;
  	ucontrol->value.enumerated.item[0] = SND_RME_CLK_SYNC(status1);
  	return 0;
  }
  
  static int snd_rme_current_freq_get(struct snd_kcontrol *kcontrol,
  				    struct snd_ctl_elem_value *ucontrol)
  {
  	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kcontrol);
  	struct snd_usb_audio *chip = list->mixer->chip;
  	u32 status1;
  	const u64 num = 104857600000000ULL;
  	u32 den;
  	unsigned int freq;
  	int err;
  
  	err = snd_usb_lock_shutdown(chip);
  	if (err < 0)
  		return err;
  	err = snd_rme_read_value(chip, SND_RME_GET_STATUS1, &status1);
  	if (err < 0)
  		goto end;
  	err = snd_rme_read_value(chip, SND_RME_GET_CURRENT_FREQ, &den);
  	if (err < 0)
  		goto end;
  	freq = (den == 0) ? 0 : div64_u64(num, den);
  	freq <<= SND_RME_CLK_FREQMUL(status1);
  	ucontrol->value.integer.value[0] = freq;
  
  end:
  	snd_usb_unlock_shutdown(chip);
  	return err;
  }
  
  static int snd_rme_rate_info(struct snd_kcontrol *kcontrol,
  			     struct snd_ctl_elem_info *uinfo)
  {
  	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
  	uinfo->count = 1;
  	switch (kcontrol->private_value) {
  	case SND_RME_DOMAIN_SYSTEM:
  		uinfo->value.integer.min = 32000;
  		uinfo->value.integer.max = 800000;
  		break;
  	case SND_RME_DOMAIN_AES:
  	case SND_RME_DOMAIN_SPDIF:
  	default:
  		uinfo->value.integer.min = 0;
  		uinfo->value.integer.max = 200000;
  	}
  	uinfo->value.integer.step = 0;
  	return 0;
  }
  
  static int snd_rme_sync_state_info(struct snd_kcontrol *kcontrol,
  				   struct snd_ctl_elem_info *uinfo)
  {
  	static const char *const sync_states[] = {
  		"No Lock", "Lock", "Sync"
  	};
  
  	return snd_ctl_enum_info(uinfo, 1,
  				 ARRAY_SIZE(sync_states), sync_states);
  }
  
  static int snd_rme_spdif_if_info(struct snd_kcontrol *kcontrol,
  				 struct snd_ctl_elem_info *uinfo)
  {
  	static const char *const spdif_if[] = {
  		"Coaxial", "Optical"
  	};
  
  	return snd_ctl_enum_info(uinfo, 1,
  				 ARRAY_SIZE(spdif_if), spdif_if);
  }
  
  static int snd_rme_spdif_format_info(struct snd_kcontrol *kcontrol,
  				     struct snd_ctl_elem_info *uinfo)
  {
  	static const char *const optical_type[] = {
  		"Consumer", "Professional"
  	};
  
  	return snd_ctl_enum_info(uinfo, 1,
  				 ARRAY_SIZE(optical_type), optical_type);
  }
  
  static int snd_rme_sync_source_info(struct snd_kcontrol *kcontrol,
  				    struct snd_ctl_elem_info *uinfo)
  {
  	static const char *const sync_sources[] = {
  		"Internal", "AES", "SPDIF", "Internal"
  	};
  
  	return snd_ctl_enum_info(uinfo, 1,
  				 ARRAY_SIZE(sync_sources), sync_sources);
  }
  
  static struct snd_kcontrol_new snd_rme_controls[] = {
  	{
  		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  		.name = "AES Rate",
  		.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
  		.info = snd_rme_rate_info,
  		.get = snd_rme_rate_get,
  		.private_value = SND_RME_DOMAIN_AES
  	},
  	{
  		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  		.name = "AES Sync",
  		.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
  		.info = snd_rme_sync_state_info,
  		.get = snd_rme_sync_state_get,
  		.private_value = SND_RME_DOMAIN_AES
  	},
  	{
  		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  		.name = "SPDIF Rate",
  		.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
  		.info = snd_rme_rate_info,
  		.get = snd_rme_rate_get,
  		.private_value = SND_RME_DOMAIN_SPDIF
  	},
  	{
  		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  		.name = "SPDIF Sync",
  		.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
  		.info = snd_rme_sync_state_info,
  		.get = snd_rme_sync_state_get,
  		.private_value = SND_RME_DOMAIN_SPDIF
  	},
  	{
  		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  		.name = "SPDIF Interface",
  		.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
  		.info = snd_rme_spdif_if_info,
  		.get = snd_rme_spdif_if_get,
  	},
  	{
  		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  		.name = "SPDIF Format",
  		.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
  		.info = snd_rme_spdif_format_info,
  		.get = snd_rme_spdif_format_get,
  	},
  	{
  		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  		.name = "Sync Source",
  		.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
  		.info = snd_rme_sync_source_info,
  		.get = snd_rme_sync_source_get
  	},
  	{
  		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  		.name = "System Rate",
  		.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
  		.info = snd_rme_rate_info,
  		.get = snd_rme_rate_get,
  		.private_value = SND_RME_DOMAIN_SYSTEM
  	},
  	{
  		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  		.name = "Current Frequency",
  		.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
  		.info = snd_rme_rate_info,
  		.get = snd_rme_current_freq_get
  	}
  };
  
  static int snd_rme_controls_create(struct usb_mixer_interface *mixer)
  {
  	int err, i;
  
  	for (i = 0; i < ARRAY_SIZE(snd_rme_controls); ++i) {
  		err = add_single_ctl_with_resume(mixer, 0,
  						 NULL,
  						 &snd_rme_controls[i],
  						 NULL);
  		if (err < 0)
  			return err;
  	}
  
  	return 0;
  }

  int snd_usb_mixer_apply_create_quirk(struct usb_mixer_interface *mixer)
  {

  	int err = 0;

  	err = snd_usb_soundblaster_remote_init(mixer);
  	if (err < 0)

  		return err;

  	switch (mixer->chip->usb_id) {

  	/* Tascam US-16x08 */
  	case USB_ID(0x0644, 0x8047):
  		err = snd_us16x08_controls_create(mixer);
  		break;

  	case USB_ID(0x041e, 0x3020):
  	case USB_ID(0x041e, 0x3040):
  	case USB_ID(0x041e, 0x3042):

  	case USB_ID(0x041e, 0x30df):

  	case USB_ID(0x041e, 0x3048):
  		err = snd_audigy2nx_controls_create(mixer);
  		if (err < 0)
  			break;

  		snd_card_ro_proc_new(mixer->chip->card, "audigy2nx",
  				     mixer, snd_audigy2nx_proc_read);

  		break;

  	/* EMU0204 */
  	case USB_ID(0x041e, 0x3f19):
  		err = snd_emu0204_controls_create(mixer);

  		break;

  	case USB_ID(0x0763, 0x2030): /* M-Audio Fast Track C400 */

  	case USB_ID(0x0763, 0x2031): /* M-Audio Fast Track C400 */

  		err = snd_c400_create_mixer(mixer);
  		break;

  	case USB_ID(0x0763, 0x2080): /* M-Audio Fast Track Ultra */
  	case USB_ID(0x0763, 0x2081): /* M-Audio Fast Track Ultra 8R */

  		err = snd_ftu_create_mixer(mixer);

  		break;

  	case USB_ID(0x0b05, 0x1739): /* ASUS Xonar U1 */
  	case USB_ID(0x0b05, 0x1743): /* ASUS Xonar U1 (2) */
  	case USB_ID(0x0b05, 0x17a0): /* ASUS Xonar U3 */

  		err = snd_xonar_u1_controls_create(mixer);

  		break;

  	case USB_ID(0x0d8c, 0x0103): /* Audio Advantage Micro II */
  		err = snd_microii_controls_create(mixer);
  		break;

  	case USB_ID(0x0dba, 0x1000): /* Digidesign Mbox 1 */
  		err = snd_mbox1_create_sync_switch(mixer);
  		break;

  	case USB_ID(0x17cc, 0x1011): /* Traktor Audio 6 */

  		err = snd_nativeinstruments_create_mixer(mixer,
  				snd_nativeinstruments_ta6_mixers,
  				ARRAY_SIZE(snd_nativeinstruments_ta6_mixers));

  		break;

  	case USB_ID(0x17cc, 0x1021): /* Traktor Audio 10 */

  		err = snd_nativeinstruments_create_mixer(mixer,
  				snd_nativeinstruments_ta10_mixers,
  				ARRAY_SIZE(snd_nativeinstruments_ta10_mixers));

  		break;

  
  	case USB_ID(0x200c, 0x1018): /* Electrix Ebox-44 */

  		/* detection is disabled in mixer_maps.c */
  		err = snd_create_std_mono_table(mixer, ebox44_table);

  		break;

  
  	case USB_ID(0x1235, 0x8012): /* Focusrite Scarlett 6i6 */
  	case USB_ID(0x1235, 0x8002): /* Focusrite Scarlett 8i6 */
  	case USB_ID(0x1235, 0x8004): /* Focusrite Scarlett 18i6 */
  	case USB_ID(0x1235, 0x8014): /* Focusrite Scarlett 18i8 */
  	case USB_ID(0x1235, 0x800c): /* Focusrite Scarlett 18i20 */
  		err = snd_scarlett_controls_create(mixer);
  		break;

  	case USB_ID(0x1235, 0x8203): /* Focusrite Scarlett 6i6 2nd Gen */
  	case USB_ID(0x1235, 0x8204): /* Focusrite Scarlett 18i8 2nd Gen */
  	case USB_ID(0x1235, 0x8201): /* Focusrite Scarlett 18i20 2nd Gen */
  		err = snd_scarlett_gen2_controls_create(mixer);
  		break;

  	case USB_ID(0x041e, 0x323b): /* Creative Sound Blaster E1 */
  		err = snd_soundblaster_e1_switch_create(mixer);
  		break;

  	case USB_ID(0x0bda, 0x4014): /* Dell WD15 dock */
  		err = dell_dock_mixer_init(mixer);
  		break;

  
  	case USB_ID(0x2a39, 0x3fd2): /* RME ADI-2 Pro */
  	case USB_ID(0x2a39, 0x3fd3): /* RME ADI-2 DAC */
  	case USB_ID(0x2a39, 0x3fd4): /* RME */
  		err = snd_rme_controls_create(mixer);
  		break;

  	}

  	return err;

  }

  #ifdef CONFIG_PM
  void snd_usb_mixer_resume_quirk(struct usb_mixer_interface *mixer)
  {
  	switch (mixer->chip->usb_id) {
  	case USB_ID(0x0bda, 0x4014): /* Dell WD15 dock */
  		dell_dock_mixer_init(mixer);
  		break;
  	}
  }
  #endif

  void snd_usb_mixer_rc_memory_change(struct usb_mixer_interface *mixer,
  				    int unitid)
  {
  	if (!mixer->rc_cfg)
  		return;
  	/* unit ids specific to Extigy/Audigy 2 NX: */
  	switch (unitid) {
  	case 0: /* remote control */
  		mixer->rc_urb->dev = mixer->chip->dev;
  		usb_submit_urb(mixer->rc_urb, GFP_ATOMIC);
  		break;
  	case 4: /* digital in jack */
  	case 7: /* line in jacks */
  	case 19: /* speaker out jacks */
  	case 20: /* headphones out jack */
  		break;
  	/* live24ext: 4 = line-in jack */
  	case 3:	/* hp-out jack (may actuate Mute) */
  		if (mixer->chip->usb_id == USB_ID(0x041e, 0x3040) ||
  		    mixer->chip->usb_id == USB_ID(0x041e, 0x3048))
  			snd_usb_mixer_notify_id(mixer, mixer->rc_cfg->mute_mixer_id);
  		break;
  	default:

  		usb_audio_dbg(mixer->chip, "memory change in unknown unit %d
  ", unitid);

  		break;
  	}
  }

  static void snd_dragonfly_quirk_db_scale(struct usb_mixer_interface *mixer,

  					 struct usb_mixer_elem_info *cval,

  					 struct snd_kcontrol *kctl)
  {
  	/* Approximation using 10 ranges based on output measurement on hw v1.2.
  	 * This seems close to the cubic mapping e.g. alsamixer uses. */
  	static const DECLARE_TLV_DB_RANGE(scale,
  		 0,  1, TLV_DB_MINMAX_ITEM(-5300, -4970),
  		 2,  5, TLV_DB_MINMAX_ITEM(-4710, -4160),
  		 6,  7, TLV_DB_MINMAX_ITEM(-3884, -3710),
  		 8, 14, TLV_DB_MINMAX_ITEM(-3443, -2560),
  		15, 16, TLV_DB_MINMAX_ITEM(-2475, -2324),
  		17, 19, TLV_DB_MINMAX_ITEM(-2228, -2031),
  		20, 26, TLV_DB_MINMAX_ITEM(-1910, -1393),
  		27, 31, TLV_DB_MINMAX_ITEM(-1322, -1032),
  		32, 40, TLV_DB_MINMAX_ITEM(-968, -490),
  		41, 50, TLV_DB_MINMAX_ITEM(-441, 0),
  	);

  	if (cval->min == 0 && cval->max == 50) {
  		usb_audio_info(mixer->chip, "applying DragonFly dB scale quirk (0-50 variant)
  ");
  		kctl->tlv.p = scale;
  		kctl->vd[0].access |= SNDRV_CTL_ELEM_ACCESS_TLV_READ;
  		kctl->vd[0].access &= ~SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
  
  	} else if (cval->min == 0 && cval->max <= 1000) {
  		/* Some other clearly broken DragonFly variant.
  		 * At least a 0..53 variant (hw v1.0) exists.
  		 */
  		usb_audio_info(mixer->chip, "ignoring too narrow dB range on a DragonFly device");
  		kctl->vd[0].access &= ~SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
  	}

  }
  
  void snd_usb_mixer_fu_apply_quirk(struct usb_mixer_interface *mixer,
  				  struct usb_mixer_elem_info *cval, int unitid,
  				  struct snd_kcontrol *kctl)
  {
  	switch (mixer->chip->usb_id) {
  	case USB_ID(0x21b4, 0x0081): /* AudioQuest DragonFly */

  		if (unitid == 7 && cval->control == UAC_FU_VOLUME)
  			snd_dragonfly_quirk_db_scale(mixer, cval, kctl);

  		break;

  	/* lowest playback value is muted on C-Media devices */
  	case USB_ID(0x0d8c, 0x000c):
  	case USB_ID(0x0d8c, 0x0014):
  		if (strstr(kctl->id.name, "Playback"))
  			cval->min_mute = 1;
  		break;

  	}
  }