sound/usb/6fire/control.c - kernel/msm-4.9 - Gitiles

 /*
  * Linux driver for TerraTec DMX 6Fire USB
  *
  * Mixer control
  *
  * Author:	Torsten Schenk <torsten.schenk@zoho.com>
  * Created:	Jan 01, 2011
  * Copyright:	(C) Torsten Schenk
  *
  * Thanks to:
  * - Holger Ruckdeschel: he found out how to control individual channel
  *   volumes and introduced mute switch
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  */

 #include <linux/interrupt.h>
 #include <sound/control.h>
 #include <sound/tlv.h>

 #include "control.h"
 #include "comm.h"
 #include "chip.h"

 static char *opt_coax_texts[2] = { "Optical", "Coax" };
 static char *line_phono_texts[2] = { "Line", "Phono" };

 /*
  * data that needs to be sent to device. sets up card internal stuff.
  * values dumped from windows driver and filtered by trial'n'error.
  */
 static const struct {
 	u8 type;
 	u8 reg;
 	u8 value;
 }
 init_data[] = {
 	{ 0x22, 0x00, 0x00 }, { 0x20, 0x00, 0x08 }, { 0x22, 0x01, 0x01 },
 	{ 0x20, 0x01, 0x08 }, { 0x22, 0x02, 0x00 }, { 0x20, 0x02, 0x08 },
 	{ 0x22, 0x03, 0x00 }, { 0x20, 0x03, 0x08 }, { 0x22, 0x04, 0x00 },
 	{ 0x20, 0x04, 0x08 }, { 0x22, 0x05, 0x01 }, { 0x20, 0x05, 0x08 },
 	{ 0x22, 0x04, 0x01 }, { 0x12, 0x04, 0x00 }, { 0x12, 0x05, 0x00 },
 	{ 0x12, 0x0d, 0x38 }, { 0x12, 0x21, 0x82 }, { 0x12, 0x22, 0x80 },
 	{ 0x12, 0x23, 0x00 }, { 0x12, 0x06, 0x02 }, { 0x12, 0x03, 0x00 },
 	{ 0x12, 0x02, 0x00 }, { 0x22, 0x03, 0x01 },
 	{ 0 } /* TERMINATING ENTRY */
 };

 static const int rates_altsetting[] = { 1, 1, 2, 2, 3, 3 };
 /* values to write to soundcard register for all samplerates */
 static const u16 rates_6fire_vl[] = {0x00, 0x01, 0x00, 0x01, 0x00, 0x01};
 static const u16 rates_6fire_vh[] = {0x11, 0x11, 0x10, 0x10, 0x00, 0x00};

 static DECLARE_TLV_DB_MINMAX(tlv_output, -9000, 0);
 static DECLARE_TLV_DB_MINMAX(tlv_input, -1500, 1500);

 enum {
 	DIGITAL_THRU_ONLY_SAMPLERATE = 3
 };

 static void usb6fire_control_output_vol_update(struct control_runtime *rt)
 {
 	struct comm_runtime *comm_rt = rt->chip->comm;
 	int i;

 	if (comm_rt)
 		for (i = 0; i < 6; i++)
 			if (!(rt->ovol_updated & (1 << i))) {
 				comm_rt->write8(comm_rt, 0x12, 0x0f + i,
 					180 - rt->output_vol[i]);
 				rt->ovol_updated |= 1 << i;
 			}
 }

 static void usb6fire_control_output_mute_update(struct control_runtime *rt)
 {
 	struct comm_runtime *comm_rt = rt->chip->comm;

 	if (comm_rt)
 		comm_rt->write8(comm_rt, 0x12, 0x0e, ~rt->output_mute);
 }

 static void usb6fire_control_input_vol_update(struct control_runtime *rt)
 {
 	struct comm_runtime *comm_rt = rt->chip->comm;
 	int i;

 	if (comm_rt)
 		for (i = 0; i < 2; i++)
 			if (!(rt->ivol_updated & (1 << i))) {
 				comm_rt->write8(comm_rt, 0x12, 0x1c + i,
 					rt->input_vol[i] & 0x3f);
 				rt->ivol_updated |= 1 << i;
 			}
 }

 static void usb6fire_control_line_phono_update(struct control_runtime *rt)
 {
 	struct comm_runtime *comm_rt = rt->chip->comm;
 	if (comm_rt) {
 		comm_rt->write8(comm_rt, 0x22, 0x02, rt->line_phono_switch);
 		comm_rt->write8(comm_rt, 0x21, 0x02, rt->line_phono_switch);
 	}
 }

 static void usb6fire_control_opt_coax_update(struct control_runtime *rt)
 {
 	struct comm_runtime *comm_rt = rt->chip->comm;
 	if (comm_rt) {
 		comm_rt->write8(comm_rt, 0x22, 0x00, rt->opt_coax_switch);
 		comm_rt->write8(comm_rt, 0x21, 0x00, rt->opt_coax_switch);
 	}
 }

 static int usb6fire_control_set_rate(struct control_runtime *rt, int rate)
 {
 	int ret;
 	struct usb_device *device = rt->chip->dev;
 	struct comm_runtime *comm_rt = rt->chip->comm;

 	if (rate < 0 || rate >= CONTROL_N_RATES)
 		return -EINVAL;

 	ret = usb_set_interface(device, 1, rates_altsetting[rate]);
 	if (ret < 0)
 		return ret;

 	/* set soundcard clock */
 	ret = comm_rt->write16(comm_rt, 0x02, 0x01, rates_6fire_vl[rate],
 			rates_6fire_vh[rate]);
 	if (ret < 0)
 		return ret;

 	return 0;
 }

 static int usb6fire_control_set_channels(
 	struct control_runtime *rt, int n_analog_out,
 	int n_analog_in, bool spdif_out, bool spdif_in)
 {
 	int ret;
 	struct comm_runtime *comm_rt = rt->chip->comm;

 	/* enable analog inputs and outputs
 	 * (one bit per stereo-channel) */
 	ret = comm_rt->write16(comm_rt, 0x02, 0x02,
 			(1 << (n_analog_out / 2)) - 1,
 			(1 << (n_analog_in / 2)) - 1);
 	if (ret < 0)
 		return ret;

 	/* disable digital inputs and outputs */
 	/* TODO: use spdif_x to enable/disable digital channels */
 	ret = comm_rt->write16(comm_rt, 0x02, 0x03, 0x00, 0x00);
 	if (ret < 0)
 		return ret;

 	return 0;
 }

 static int usb6fire_control_streaming_update(struct control_runtime *rt)
 {
 	struct comm_runtime *comm_rt = rt->chip->comm;

 	if (comm_rt) {
 		if (!rt->usb_streaming && rt->digital_thru_switch)
 			usb6fire_control_set_rate(rt,
 				DIGITAL_THRU_ONLY_SAMPLERATE);
 		return comm_rt->write16(comm_rt, 0x02, 0x00, 0x00,
 			(rt->usb_streaming ? 0x01 : 0x00) |
 			(rt->digital_thru_switch ? 0x08 : 0x00));
 	}
 	return -EINVAL;
 }

 static int usb6fire_control_output_vol_info(struct snd_kcontrol *kcontrol,
 		struct snd_ctl_elem_info *uinfo)
 {
 	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 	uinfo->count = 2;
 	uinfo->value.integer.min = 0;
 	uinfo->value.integer.max = 180;
 	return 0;
 }

 static int usb6fire_control_output_vol_put(struct snd_kcontrol *kcontrol,
 		struct snd_ctl_elem_value *ucontrol)
 {
 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
 	unsigned int ch = kcontrol->private_value;
 	int changed = 0;

 	if (ch > 4) {
 		snd_printk(KERN_ERR PREFIX "Invalid channel in volume control.");
 		return -EINVAL;
 	}

 	if (rt->output_vol[ch] != ucontrol->value.integer.value[0]) {
 		rt->output_vol[ch] = ucontrol->value.integer.value[0];
 		rt->ovol_updated &= ~(1 << ch);
 		changed = 1;
 	}
 	if (rt->output_vol[ch + 1] != ucontrol->value.integer.value[1]) {
 		rt->output_vol[ch + 1] = ucontrol->value.integer.value[1];
 		rt->ovol_updated &= ~(2 << ch);
 		changed = 1;
 	}

 	if (changed)
 		usb6fire_control_output_vol_update(rt);

 	return changed;
 }

 static int usb6fire_control_output_vol_get(struct snd_kcontrol *kcontrol,
 		struct snd_ctl_elem_value *ucontrol)
 {
 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
 	unsigned int ch = kcontrol->private_value;

 	if (ch > 4) {
 		snd_printk(KERN_ERR PREFIX "Invalid channel in volume control.");
 		return -EINVAL;
 	}

 	ucontrol->value.integer.value[0] = rt->output_vol[ch];
 	ucontrol->value.integer.value[1] = rt->output_vol[ch + 1];
 	return 0;
 }

 static int usb6fire_control_output_mute_put(struct snd_kcontrol *kcontrol,
 	struct snd_ctl_elem_value *ucontrol)
 {
 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
 	unsigned int ch = kcontrol->private_value;
 	u8 old = rt->output_mute;
 	u8 value = 0;

 	if (ch > 4) {
 		snd_printk(KERN_ERR PREFIX "Invalid channel in volume control.");
 		return -EINVAL;
 	}

 	rt->output_mute &= ~(3 << ch);
 	if (ucontrol->value.integer.value[0])
 		value |= 1;
 	if (ucontrol->value.integer.value[1])
 		value |= 2;
 	rt->output_mute |= value << ch;

 	if (rt->output_mute != old)
 		usb6fire_control_output_mute_update(rt);

 	return rt->output_mute != old;
 }

 static int usb6fire_control_output_mute_get(struct snd_kcontrol *kcontrol,
 	struct snd_ctl_elem_value *ucontrol)
 {
 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
 	unsigned int ch = kcontrol->private_value;
 	u8 value = rt->output_mute >> ch;

 	if (ch > 4) {
 		snd_printk(KERN_ERR PREFIX "Invalid channel in volume control.");
 		return -EINVAL;
 	}

 	ucontrol->value.integer.value[0] = 1 & value;
 	value >>= 1;
 	ucontrol->value.integer.value[1] = 1 & value;

 	return 0;
 }

 static int usb6fire_control_input_vol_info(struct snd_kcontrol *kcontrol,
 		struct snd_ctl_elem_info *uinfo)
 {
 	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 	uinfo->count = 2;
 	uinfo->value.integer.min = 0;
 	uinfo->value.integer.max = 30;
 	return 0;
 }

 static int usb6fire_control_input_vol_put(struct snd_kcontrol *kcontrol,
 		struct snd_ctl_elem_value *ucontrol)
 {
 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
 	int changed = 0;

 	if (rt->input_vol[0] != ucontrol->value.integer.value[0]) {
 		rt->input_vol[0] = ucontrol->value.integer.value[0] - 15;
 		rt->ivol_updated &= ~(1 << 0);
 		changed = 1;
 	}
 	if (rt->input_vol[1] != ucontrol->value.integer.value[1]) {
 		rt->input_vol[1] = ucontrol->value.integer.value[1] - 15;
 		rt->ivol_updated &= ~(1 << 1);
 		changed = 1;
 	}

 	if (changed)
 		usb6fire_control_input_vol_update(rt);

 	return changed;
 }

 static int usb6fire_control_input_vol_get(struct snd_kcontrol *kcontrol,
 		struct snd_ctl_elem_value *ucontrol)
 {
 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);

 	ucontrol->value.integer.value[0] = rt->input_vol[0] + 15;
 	ucontrol->value.integer.value[1] = rt->input_vol[1] + 15;

 	return 0;
 }

 static int usb6fire_control_line_phono_info(struct snd_kcontrol *kcontrol,
 		struct snd_ctl_elem_info *uinfo)
 {
 	uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
 	uinfo->count = 1;
 	uinfo->value.enumerated.items = 2;
 	if (uinfo->value.enumerated.item > 1)
 		uinfo->value.enumerated.item = 1;
 	strcpy(uinfo->value.enumerated.name,
 			line_phono_texts[uinfo->value.enumerated.item]);
 	return 0;
 }

 static int usb6fire_control_line_phono_put(struct snd_kcontrol *kcontrol,
 		struct snd_ctl_elem_value *ucontrol)
 {
 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
 	int changed = 0;
 	if (rt->line_phono_switch != ucontrol->value.integer.value[0]) {
 		rt->line_phono_switch = ucontrol->value.integer.value[0];
 		usb6fire_control_line_phono_update(rt);
 		changed = 1;
 	}
 	return changed;
 }

 static int usb6fire_control_line_phono_get(struct snd_kcontrol *kcontrol,
 		struct snd_ctl_elem_value *ucontrol)
 {
 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
 	ucontrol->value.integer.value[0] = rt->line_phono_switch;
 	return 0;
 }

 static int usb6fire_control_opt_coax_info(struct snd_kcontrol *kcontrol,
 		struct snd_ctl_elem_info *uinfo)
 {
 	uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
 	uinfo->count = 1;
 	uinfo->value.enumerated.items = 2;
 	if (uinfo->value.enumerated.item > 1)
 		uinfo->value.enumerated.item = 1;
 	strcpy(uinfo->value.enumerated.name,
 			opt_coax_texts[uinfo->value.enumerated.item]);
 	return 0;
 }

 static int usb6fire_control_opt_coax_put(struct snd_kcontrol *kcontrol,
 		struct snd_ctl_elem_value *ucontrol)
 {
 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
 	int changed = 0;

 	if (rt->opt_coax_switch != ucontrol->value.enumerated.item[0]) {
 		rt->opt_coax_switch = ucontrol->value.enumerated.item[0];
 		usb6fire_control_opt_coax_update(rt);
 		changed = 1;
 	}
 	return changed;
 }

 static int usb6fire_control_opt_coax_get(struct snd_kcontrol *kcontrol,
 		struct snd_ctl_elem_value *ucontrol)
 {
 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
 	ucontrol->value.enumerated.item[0] = rt->opt_coax_switch;
 	return 0;
 }

 static int usb6fire_control_digital_thru_put(struct snd_kcontrol *kcontrol,
 		struct snd_ctl_elem_value *ucontrol)
 {
 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
 	int changed = 0;

 	if (rt->digital_thru_switch != ucontrol->value.integer.value[0]) {
 		rt->digital_thru_switch = ucontrol->value.integer.value[0];
 		usb6fire_control_streaming_update(rt);
 		changed = 1;
 	}
 	return changed;
 }

 static int usb6fire_control_digital_thru_get(struct snd_kcontrol *kcontrol,
 		struct snd_ctl_elem_value *ucontrol)
 {
 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
 	ucontrol->value.integer.value[0] = rt->digital_thru_switch;
 	return 0;
 }

 static struct __devinitdata snd_kcontrol_new vol_elements[] = {
 	{
 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 		.name = "Analog Playback Volume",
 		.index = 0,
 		.private_value = 0,
 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
 			SNDRV_CTL_ELEM_ACCESS_TLV_READ,
 		.info = usb6fire_control_output_vol_info,
 		.get = usb6fire_control_output_vol_get,
 		.put = usb6fire_control_output_vol_put,
 		.tlv = { .p = tlv_output }
 	},
 	{
 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 		.name = "Analog Playback Volume",
 		.index = 1,
 		.private_value = 2,
 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
 			SNDRV_CTL_ELEM_ACCESS_TLV_READ,
 		.info = usb6fire_control_output_vol_info,
 		.get = usb6fire_control_output_vol_get,
 		.put = usb6fire_control_output_vol_put,
 		.tlv = { .p = tlv_output }
 	},
 	{
 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 		.name = "Analog Playback Volume",
 		.index = 2,
 		.private_value = 4,
 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
 			SNDRV_CTL_ELEM_ACCESS_TLV_READ,
 		.info = usb6fire_control_output_vol_info,
 		.get = usb6fire_control_output_vol_get,
 		.put = usb6fire_control_output_vol_put,
 		.tlv = { .p = tlv_output }
 	},
 	{}
 };

 static struct __devinitdata snd_kcontrol_new mute_elements[] = {
 	{
 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 		.name = "Analog Playback Switch",
 		.index = 0,
 		.private_value = 0,
 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
 		.info = snd_ctl_boolean_stereo_info,
 		.get = usb6fire_control_output_mute_get,
 		.put = usb6fire_control_output_mute_put,
 	},
 	{
 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 		.name = "Analog Playback Switch",
 		.index = 1,
 		.private_value = 2,
 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
 		.info = snd_ctl_boolean_stereo_info,
 		.get = usb6fire_control_output_mute_get,
 		.put = usb6fire_control_output_mute_put,
 	},
 	{
 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 		.name = "Analog Playback Switch",
 		.index = 2,
 		.private_value = 4,
 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
 		.info = snd_ctl_boolean_stereo_info,
 		.get = usb6fire_control_output_mute_get,
 		.put = usb6fire_control_output_mute_put,
 	},
 	{}
 };

 static struct __devinitdata snd_kcontrol_new elements[] = {
 	{
 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 		.name = "Line/Phono Capture Route",
 		.index = 0,
 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
 		.info = usb6fire_control_line_phono_info,
 		.get = usb6fire_control_line_phono_get,
 		.put = usb6fire_control_line_phono_put
 	},
 	{
 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 		.name = "Opt/Coax Capture Route",
 		.index = 0,
 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
 		.info = usb6fire_control_opt_coax_info,
 		.get = usb6fire_control_opt_coax_get,
 		.put = usb6fire_control_opt_coax_put
 	},
 	{
 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 		.name = "Digital Thru Playback Route",
 		.index = 0,
 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
 		.info = snd_ctl_boolean_mono_info,
 		.get = usb6fire_control_digital_thru_get,
 		.put = usb6fire_control_digital_thru_put
 	},
 	{
 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 		.name = "Analog Capture Volume",
 		.index = 0,
 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
 			SNDRV_CTL_ELEM_ACCESS_TLV_READ,
 		.info = usb6fire_control_input_vol_info,
 		.get = usb6fire_control_input_vol_get,
 		.put = usb6fire_control_input_vol_put,
 		.tlv = { .p = tlv_input }
 	},
 	{}
 };

 static int usb6fire_control_add_virtual(
 	struct control_runtime *rt,
 	struct snd_card *card,
 	char *name,
 	struct snd_kcontrol_new *elems)
 {
 	int ret;
 	int i;
 	struct snd_kcontrol *vmaster =
 		snd_ctl_make_virtual_master(name, tlv_output);
 	struct snd_kcontrol *control;

 	if (!vmaster)
 		return -ENOMEM;
 	ret = snd_ctl_add(card, vmaster);
 	if (ret < 0)
 		return ret;

 	i = 0;
 	while (elems[i].name) {
 		control = snd_ctl_new1(&elems[i], rt);
 		if (!control)
 			return -ENOMEM;
 		ret = snd_ctl_add(card, control);
 		if (ret < 0)
 			return ret;
 		ret = snd_ctl_add_slave(vmaster, control);
 		if (ret < 0)
 			return ret;
 		i++;
 	}
 	return 0;
 }

 int __devinit usb6fire_control_init(struct sfire_chip *chip)
 {
 	int i;
 	int ret;
 	struct control_runtime *rt = kzalloc(sizeof(struct control_runtime),
 			GFP_KERNEL);
 	struct comm_runtime *comm_rt = chip->comm;

 	if (!rt)
 		return -ENOMEM;

 	rt->chip = chip;
 	rt->update_streaming = usb6fire_control_streaming_update;
 	rt->set_rate = usb6fire_control_set_rate;
 	rt->set_channels = usb6fire_control_set_channels;

 	i = 0;
 	while (init_data[i].type) {
 		comm_rt->write8(comm_rt, init_data[i].type, init_data[i].reg,
 				init_data[i].value);
 		i++;
 	}

 	usb6fire_control_opt_coax_update(rt);
 	usb6fire_control_line_phono_update(rt);
 	usb6fire_control_output_vol_update(rt);
 	usb6fire_control_output_mute_update(rt);
 	usb6fire_control_input_vol_update(rt);
 	usb6fire_control_streaming_update(rt);

 	ret = usb6fire_control_add_virtual(rt, chip->card,
 		"Master Playback Volume", vol_elements);
 	if (ret) {
 		snd_printk(KERN_ERR PREFIX "cannot add control.\n");
 		kfree(rt);
 		return ret;
 	}
 	ret = usb6fire_control_add_virtual(rt, chip->card,
 		"Master Playback Switch", mute_elements);
 	if (ret) {
 		snd_printk(KERN_ERR PREFIX "cannot add control.\n");
 		kfree(rt);
 		return ret;
 	}

 	i = 0;
 	while (elements[i].name) {
 		ret = snd_ctl_add(chip->card, snd_ctl_new1(&elements[i], rt));
 		if (ret < 0) {
 			kfree(rt);
 			snd_printk(KERN_ERR PREFIX "cannot add control.\n");
 			return ret;
 		}
 		i++;
 	}

 	chip->control = rt;
 	return 0;
 }

 void usb6fire_control_abort(struct sfire_chip *chip)
 {}

 void usb6fire_control_destroy(struct sfire_chip *chip)
 {
 	kfree(chip->control);
 	chip->control = NULL;
 }
	/*
	* Linux driver for TerraTec DMX 6Fire USB
	*
	* Mixer control
	*
	* Author: Torsten Schenk <torsten.schenk@zoho.com>
	* Created: Jan 01, 2011
	* Copyright: (C) Torsten Schenk
	*
	* Thanks to:
	* - Holger Ruckdeschel: he found out how to control individual channel
	* volumes and introduced mute switch
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*/

	#include <linux/interrupt.h>
	#include <sound/control.h>
	#include <sound/tlv.h>

	#include "control.h"
	#include "comm.h"
	#include "chip.h"

	static char *opt_coax_texts[2] = { "Optical", "Coax" };
	static char *line_phono_texts[2] = { "Line", "Phono" };

	/*
	* data that needs to be sent to device. sets up card internal stuff.
	* values dumped from windows driver and filtered by trial'n'error.
	*/
	static const struct {
	u8 type;
	u8 reg;
	u8 value;
	}
	init_data[] = {
	{ 0x22, 0x00, 0x00 }, { 0x20, 0x00, 0x08 }, { 0x22, 0x01, 0x01 },
	{ 0x20, 0x01, 0x08 }, { 0x22, 0x02, 0x00 }, { 0x20, 0x02, 0x08 },
	{ 0x22, 0x03, 0x00 }, { 0x20, 0x03, 0x08 }, { 0x22, 0x04, 0x00 },
	{ 0x20, 0x04, 0x08 }, { 0x22, 0x05, 0x01 }, { 0x20, 0x05, 0x08 },
	{ 0x22, 0x04, 0x01 }, { 0x12, 0x04, 0x00 }, { 0x12, 0x05, 0x00 },
	{ 0x12, 0x0d, 0x38 }, { 0x12, 0x21, 0x82 }, { 0x12, 0x22, 0x80 },
	{ 0x12, 0x23, 0x00 }, { 0x12, 0x06, 0x02 }, { 0x12, 0x03, 0x00 },
	{ 0x12, 0x02, 0x00 }, { 0x22, 0x03, 0x01 },
	{ 0 } /* TERMINATING ENTRY */
	};

	static const int rates_altsetting[] = { 1, 1, 2, 2, 3, 3 };
	/* values to write to soundcard register for all samplerates */
	static const u16 rates_6fire_vl[] = {0x00, 0x01, 0x00, 0x01, 0x00, 0x01};
	static const u16 rates_6fire_vh[] = {0x11, 0x11, 0x10, 0x10, 0x00, 0x00};

	static DECLARE_TLV_DB_MINMAX(tlv_output, -9000, 0);
	static DECLARE_TLV_DB_MINMAX(tlv_input, -1500, 1500);

	enum {
	DIGITAL_THRU_ONLY_SAMPLERATE = 3
	};

	static void usb6fire_control_output_vol_update(struct control_runtime *rt)
	{
	struct comm_runtime *comm_rt = rt->chip->comm;
	int i;

	if (comm_rt)
	for (i = 0; i < 6; i++)
	if (!(rt->ovol_updated & (1 << i))) {
	comm_rt->write8(comm_rt, 0x12, 0x0f + i,
	180 - rt->output_vol[i]);
	rt->ovol_updated \|= 1 << i;
	}
	}

	static void usb6fire_control_output_mute_update(struct control_runtime *rt)
	{
	struct comm_runtime *comm_rt = rt->chip->comm;

	if (comm_rt)
	comm_rt->write8(comm_rt, 0x12, 0x0e, ~rt->output_mute);
	}

	static void usb6fire_control_input_vol_update(struct control_runtime *rt)
	{
	struct comm_runtime *comm_rt = rt->chip->comm;
	int i;

	if (comm_rt)
	for (i = 0; i < 2; i++)
	if (!(rt->ivol_updated & (1 << i))) {
	comm_rt->write8(comm_rt, 0x12, 0x1c + i,
	rt->input_vol[i] & 0x3f);
	rt->ivol_updated \|= 1 << i;
	}
	}

	static void usb6fire_control_line_phono_update(struct control_runtime *rt)
	{
	struct comm_runtime *comm_rt = rt->chip->comm;
	if (comm_rt) {
	comm_rt->write8(comm_rt, 0x22, 0x02, rt->line_phono_switch);
	comm_rt->write8(comm_rt, 0x21, 0x02, rt->line_phono_switch);
	}
	}

	static void usb6fire_control_opt_coax_update(struct control_runtime *rt)
	{
	struct comm_runtime *comm_rt = rt->chip->comm;
	if (comm_rt) {
	comm_rt->write8(comm_rt, 0x22, 0x00, rt->opt_coax_switch);
	comm_rt->write8(comm_rt, 0x21, 0x00, rt->opt_coax_switch);
	}
	}

	static int usb6fire_control_set_rate(struct control_runtime *rt, int rate)
	{
	int ret;
	struct usb_device *device = rt->chip->dev;
	struct comm_runtime *comm_rt = rt->chip->comm;

	if (rate < 0 \|\| rate >= CONTROL_N_RATES)
	return -EINVAL;

	ret = usb_set_interface(device, 1, rates_altsetting[rate]);
	if (ret < 0)
	return ret;

	/* set soundcard clock */
	ret = comm_rt->write16(comm_rt, 0x02, 0x01, rates_6fire_vl[rate],
	rates_6fire_vh[rate]);
	if (ret < 0)
	return ret;

	return 0;
	}

	static int usb6fire_control_set_channels(
	struct control_runtime *rt, int n_analog_out,
	int n_analog_in, bool spdif_out, bool spdif_in)
	{
	int ret;
	struct comm_runtime *comm_rt = rt->chip->comm;

	/* enable analog inputs and outputs
	* (one bit per stereo-channel) */
	ret = comm_rt->write16(comm_rt, 0x02, 0x02,
	(1 << (n_analog_out / 2)) - 1,
	(1 << (n_analog_in / 2)) - 1);
	if (ret < 0)
	return ret;

	/* disable digital inputs and outputs */
	/* TODO: use spdif_x to enable/disable digital channels */
	ret = comm_rt->write16(comm_rt, 0x02, 0x03, 0x00, 0x00);
	if (ret < 0)
	return ret;

	return 0;
	}

	static int usb6fire_control_streaming_update(struct control_runtime *rt)
	{
	struct comm_runtime *comm_rt = rt->chip->comm;

	if (comm_rt) {
	if (!rt->usb_streaming && rt->digital_thru_switch)
	usb6fire_control_set_rate(rt,
	DIGITAL_THRU_ONLY_SAMPLERATE);
	return comm_rt->write16(comm_rt, 0x02, 0x00, 0x00,
	(rt->usb_streaming ? 0x01 : 0x00) \|
	(rt->digital_thru_switch ? 0x08 : 0x00));
	}
	return -EINVAL;
	}

	static int usb6fire_control_output_vol_info(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_info *uinfo)
	{
	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
	uinfo->count = 2;
	uinfo->value.integer.min = 0;
	uinfo->value.integer.max = 180;
	return 0;
	}

	static int usb6fire_control_output_vol_put(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_value *ucontrol)
	{
	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
	unsigned int ch = kcontrol->private_value;
	int changed = 0;

	if (ch > 4) {
	snd_printk(KERN_ERR PREFIX "Invalid channel in volume control.");
	return -EINVAL;
	}

	if (rt->output_vol[ch] != ucontrol->value.integer.value[0]) {
	rt->output_vol[ch] = ucontrol->value.integer.value[0];
	rt->ovol_updated &= ~(1 << ch);
	changed = 1;
	}
	if (rt->output_vol[ch + 1] != ucontrol->value.integer.value[1]) {
	rt->output_vol[ch + 1] = ucontrol->value.integer.value[1];
	rt->ovol_updated &= ~(2 << ch);
	changed = 1;
	}

	if (changed)
	usb6fire_control_output_vol_update(rt);

	return changed;
	}

	static int usb6fire_control_output_vol_get(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_value *ucontrol)
	{
	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
	unsigned int ch = kcontrol->private_value;

	if (ch > 4) {
	snd_printk(KERN_ERR PREFIX "Invalid channel in volume control.");
	return -EINVAL;
	}

	ucontrol->value.integer.value[0] = rt->output_vol[ch];
	ucontrol->value.integer.value[1] = rt->output_vol[ch + 1];
	return 0;
	}

	static int usb6fire_control_output_mute_put(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_value *ucontrol)
	{
	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
	unsigned int ch = kcontrol->private_value;
	u8 old = rt->output_mute;
	u8 value = 0;

	if (ch > 4) {
	snd_printk(KERN_ERR PREFIX "Invalid channel in volume control.");
	return -EINVAL;
	}

	rt->output_mute &= ~(3 << ch);
	if (ucontrol->value.integer.value[0])
	value \|= 1;
	if (ucontrol->value.integer.value[1])
	value \|= 2;
	rt->output_mute \|= value << ch;

	if (rt->output_mute != old)
	usb6fire_control_output_mute_update(rt);

	return rt->output_mute != old;
	}

	static int usb6fire_control_output_mute_get(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_value *ucontrol)
	{
	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
	unsigned int ch = kcontrol->private_value;
	u8 value = rt->output_mute >> ch;

	if (ch > 4) {
	snd_printk(KERN_ERR PREFIX "Invalid channel in volume control.");
	return -EINVAL;
	}

	ucontrol->value.integer.value[0] = 1 & value;
	value >>= 1;
	ucontrol->value.integer.value[1] = 1 & value;

	return 0;
	}

	static int usb6fire_control_input_vol_info(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_info *uinfo)
	{
	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
	uinfo->count = 2;
	uinfo->value.integer.min = 0;
	uinfo->value.integer.max = 30;
	return 0;
	}

	static int usb6fire_control_input_vol_put(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_value *ucontrol)
	{
	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
	int changed = 0;

	if (rt->input_vol[0] != ucontrol->value.integer.value[0]) {
	rt->input_vol[0] = ucontrol->value.integer.value[0] - 15;
	rt->ivol_updated &= ~(1 << 0);
	changed = 1;
	}
	if (rt->input_vol[1] != ucontrol->value.integer.value[1]) {
	rt->input_vol[1] = ucontrol->value.integer.value[1] - 15;
	rt->ivol_updated &= ~(1 << 1);
	changed = 1;
	}

	if (changed)
	usb6fire_control_input_vol_update(rt);

	return changed;
	}

	static int usb6fire_control_input_vol_get(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_value *ucontrol)
	{
	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);

	ucontrol->value.integer.value[0] = rt->input_vol[0] + 15;
	ucontrol->value.integer.value[1] = rt->input_vol[1] + 15;

	return 0;
	}

	static int usb6fire_control_line_phono_info(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_info *uinfo)
	{
	uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
	uinfo->count = 1;
	uinfo->value.enumerated.items = 2;
	if (uinfo->value.enumerated.item > 1)
	uinfo->value.enumerated.item = 1;
	strcpy(uinfo->value.enumerated.name,
	line_phono_texts[uinfo->value.enumerated.item]);
	return 0;
	}

	static int usb6fire_control_line_phono_put(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_value *ucontrol)
	{
	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
	int changed = 0;
	if (rt->line_phono_switch != ucontrol->value.integer.value[0]) {
	rt->line_phono_switch = ucontrol->value.integer.value[0];
	usb6fire_control_line_phono_update(rt);
	changed = 1;
	}
	return changed;
	}

	static int usb6fire_control_line_phono_get(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_value *ucontrol)
	{
	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
	ucontrol->value.integer.value[0] = rt->line_phono_switch;
	return 0;
	}

	static int usb6fire_control_opt_coax_info(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_info *uinfo)
	{
	uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
	uinfo->count = 1;
	uinfo->value.enumerated.items = 2;
	if (uinfo->value.enumerated.item > 1)
	uinfo->value.enumerated.item = 1;
	strcpy(uinfo->value.enumerated.name,
	opt_coax_texts[uinfo->value.enumerated.item]);
	return 0;
	}

	static int usb6fire_control_opt_coax_put(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_value *ucontrol)
	{
	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
	int changed = 0;

	if (rt->opt_coax_switch != ucontrol->value.enumerated.item[0]) {
	rt->opt_coax_switch = ucontrol->value.enumerated.item[0];
	usb6fire_control_opt_coax_update(rt);
	changed = 1;
	}
	return changed;
	}

	static int usb6fire_control_opt_coax_get(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_value *ucontrol)
	{
	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
	ucontrol->value.enumerated.item[0] = rt->opt_coax_switch;
	return 0;
	}

	static int usb6fire_control_digital_thru_put(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_value *ucontrol)
	{
	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
	int changed = 0;

	if (rt->digital_thru_switch != ucontrol->value.integer.value[0]) {
	rt->digital_thru_switch = ucontrol->value.integer.value[0];
	usb6fire_control_streaming_update(rt);
	changed = 1;
	}
	return changed;
	}

	static int usb6fire_control_digital_thru_get(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_value *ucontrol)
	{
	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
	ucontrol->value.integer.value[0] = rt->digital_thru_switch;
	return 0;
	}

	static struct __devinitdata snd_kcontrol_new vol_elements[] = {
	{
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "Analog Playback Volume",
	.index = 0,
	.private_value = 0,
	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE \|
	SNDRV_CTL_ELEM_ACCESS_TLV_READ,
	.info = usb6fire_control_output_vol_info,
	.get = usb6fire_control_output_vol_get,
	.put = usb6fire_control_output_vol_put,
	.tlv = { .p = tlv_output }
	},
	{
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "Analog Playback Volume",
	.index = 1,
	.private_value = 2,
	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE \|
	SNDRV_CTL_ELEM_ACCESS_TLV_READ,
	.info = usb6fire_control_output_vol_info,
	.get = usb6fire_control_output_vol_get,
	.put = usb6fire_control_output_vol_put,
	.tlv = { .p = tlv_output }
	},
	{
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "Analog Playback Volume",
	.index = 2,
	.private_value = 4,
	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE \|
	SNDRV_CTL_ELEM_ACCESS_TLV_READ,
	.info = usb6fire_control_output_vol_info,
	.get = usb6fire_control_output_vol_get,
	.put = usb6fire_control_output_vol_put,
	.tlv = { .p = tlv_output }
	},
	{}
	};

	static struct __devinitdata snd_kcontrol_new mute_elements[] = {
	{
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "Analog Playback Switch",
	.index = 0,
	.private_value = 0,
	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
	.info = snd_ctl_boolean_stereo_info,
	.get = usb6fire_control_output_mute_get,
	.put = usb6fire_control_output_mute_put,
	},
	{
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "Analog Playback Switch",
	.index = 1,
	.private_value = 2,
	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
	.info = snd_ctl_boolean_stereo_info,
	.get = usb6fire_control_output_mute_get,
	.put = usb6fire_control_output_mute_put,
	},
	{
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "Analog Playback Switch",
	.index = 2,
	.private_value = 4,
	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
	.info = snd_ctl_boolean_stereo_info,
	.get = usb6fire_control_output_mute_get,
	.put = usb6fire_control_output_mute_put,
	},
	{}
	};

	static struct __devinitdata snd_kcontrol_new elements[] = {
	{
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "Line/Phono Capture Route",
	.index = 0,
	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
	.info = usb6fire_control_line_phono_info,
	.get = usb6fire_control_line_phono_get,
	.put = usb6fire_control_line_phono_put
	},
	{
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "Opt/Coax Capture Route",
	.index = 0,
	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
	.info = usb6fire_control_opt_coax_info,
	.get = usb6fire_control_opt_coax_get,
	.put = usb6fire_control_opt_coax_put
	},
	{
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "Digital Thru Playback Route",
	.index = 0,
	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
	.info = snd_ctl_boolean_mono_info,
	.get = usb6fire_control_digital_thru_get,
	.put = usb6fire_control_digital_thru_put
	},
	{
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "Analog Capture Volume",
	.index = 0,
	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE \|
	SNDRV_CTL_ELEM_ACCESS_TLV_READ,
	.info = usb6fire_control_input_vol_info,
	.get = usb6fire_control_input_vol_get,
	.put = usb6fire_control_input_vol_put,
	.tlv = { .p = tlv_input }
	},
	{}
	};

	static int usb6fire_control_add_virtual(
	struct control_runtime *rt,
	struct snd_card *card,
	char *name,
	struct snd_kcontrol_new *elems)
	{
	int ret;
	int i;
	struct snd_kcontrol *vmaster =
	snd_ctl_make_virtual_master(name, tlv_output);
	struct snd_kcontrol *control;

	if (!vmaster)
	return -ENOMEM;
	ret = snd_ctl_add(card, vmaster);
	if (ret < 0)
	return ret;

	i = 0;
	while (elems[i].name) {
	control = snd_ctl_new1(&elems[i], rt);
	if (!control)
	return -ENOMEM;
	ret = snd_ctl_add(card, control);
	if (ret < 0)
	return ret;
	ret = snd_ctl_add_slave(vmaster, control);
	if (ret < 0)
	return ret;
	i++;
	}
	return 0;
	}

	int __devinit usb6fire_control_init(struct sfire_chip *chip)
	{
	int i;
	int ret;
	struct control_runtime *rt = kzalloc(sizeof(struct control_runtime),
	GFP_KERNEL);
	struct comm_runtime *comm_rt = chip->comm;

	if (!rt)
	return -ENOMEM;

	rt->chip = chip;
	rt->update_streaming = usb6fire_control_streaming_update;
	rt->set_rate = usb6fire_control_set_rate;
	rt->set_channels = usb6fire_control_set_channels;

	i = 0;
	while (init_data[i].type) {
	comm_rt->write8(comm_rt, init_data[i].type, init_data[i].reg,
	init_data[i].value);
	i++;
	}

	usb6fire_control_opt_coax_update(rt);
	usb6fire_control_line_phono_update(rt);
	usb6fire_control_output_vol_update(rt);
	usb6fire_control_output_mute_update(rt);
	usb6fire_control_input_vol_update(rt);
	usb6fire_control_streaming_update(rt);

	ret = usb6fire_control_add_virtual(rt, chip->card,
	"Master Playback Volume", vol_elements);
	if (ret) {
	snd_printk(KERN_ERR PREFIX "cannot add control.\n");
	kfree(rt);
	return ret;
	}
	ret = usb6fire_control_add_virtual(rt, chip->card,
	"Master Playback Switch", mute_elements);
	if (ret) {
	snd_printk(KERN_ERR PREFIX "cannot add control.\n");
	kfree(rt);
	return ret;
	}

	i = 0;
	while (elements[i].name) {
	ret = snd_ctl_add(chip->card, snd_ctl_new1(&elements[i], rt));
	if (ret < 0) {
	kfree(rt);
	snd_printk(KERN_ERR PREFIX "cannot add control.\n");
	return ret;
	}
	i++;
	}

	chip->control = rt;
	return 0;
	}

	void usb6fire_control_abort(struct sfire_chip *chip)
	{}

	void usb6fire_control_destroy(struct sfire_chip *chip)
	{
	kfree(chip->control);
	chip->control = NULL;
	}