[PATCH 2/3] Add Audient EVO4 mixer quirks
From: Christian Ruppert
Date: Sat Sep 19 2026 - 11:20:10 EST
The controls enumerated by the Audient EVO4 are incomplete. Add missing
controls for
* channel muting
* the cross-fader
* the recording mixer
* phantom power
The driver is structured so that it should be trivial to extend it to the
EVO8 (and potentially other Audient devices) but we need a kind soul who
has access to that hardware to correctly map the control names and test
everything.
Signed-off-by: Christian Ruppert <arc@xxxxxx>
---
MAINTAINERS | 7 +
sound/usb/Makefile | 1 +
sound/usb/mixer_evo.c | 505 +++++++++++++++++++++++++++++++++++++++
sound/usb/mixer_evo.h | 12 +
sound/usb/mixer_quirks.c | 5 +
5 files changed, 530 insertions(+)
create mode 100644 sound/usb/mixer_evo.c
create mode 100644 sound/usb/mixer_evo.h
diff --git a/MAINTAINERS b/MAINTAINERS
index c2414447892c..5f8df442b1a5 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4346,6 +4346,13 @@ F: drivers/net/ieee802154/at86rf230.h
F: drivers/net/ieee802154/atusb.c
F: drivers/net/ieee802154/atusb.h
+AUDIENT EVO MIXER DRIVER
+M: Christian Ruppert <arc@xxxxxx>
+L: linux-sound@xxxxxxxxxxxxxxx
+S: Maintained
+F: sound/usb/mixer_evo.c
+F: sound/usb/mixer_evo.h
+
AUDIT SUBSYSTEM
M: Paul Moore <paul@xxxxxxxxxxxxxx>
M: Eric Paris <eparis@xxxxxxxxxx>
diff --git a/sound/usb/Makefile b/sound/usb/Makefile
index e62794a87e73..2e842dcc73de 100644
--- a/sound/usb/Makefile
+++ b/sound/usb/Makefile
@@ -11,6 +11,7 @@ snd-usb-audio-y := card.o \
helper.o \
implicit.o \
mixer.o \
+ mixer_evo.o \
mixer_quirks.o \
mixer_scarlett.o \
mixer_scarlett2.o \
diff --git a/sound/usb/mixer_evo.c b/sound/usb/mixer_evo.c
new file mode 100644
index 000000000000..c327b82c8d2d
--- /dev/null
+++ b/sound/usb/mixer_evo.c
@@ -0,0 +1,505 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Audient EVO driver for ALSA
+ * Copyright (C) 2026 Christian Ruppert <arc@xxxxxx>
+ *
+ * Based on the work of Ivan Hazucha for audient-evo-py.
+ * https://github.com/vanzaho/audient-evo-py/
+ */
+
+
+#include <asm/byteorder.h>
+#include <linux/usb.h>
+#include <linux/usb/audio-v2.h>
+#include <linux/slab.h>
+#include <sound/core.h>
+#include <sound/control.h>
+
+#include "usbaudio.h"
+#include "mixer.h"
+#include "mixer_quirks.h"
+#include "helper.h"
+#include "mixer_evo.h"
+
+
+enum snd_evo_type {
+ SND_EVO_TYPE_MONITOR = 0,
+ SND_EVO_TYPE_PHANTOM,
+ SND_EVO_TYPE_MUTE,
+ SND_EVO_TYPE_MUTE_OUT,
+ SND_EVO_TYPE_MIXER,
+ SND_EVO_TYPE_NCTYPES
+};
+
+static const struct snd_evo_ctrl_type {
+ snd_ctl_elem_type_t type;
+ bool invert;
+ union {
+ int integer;
+ } min;
+ union {
+ int integer;
+ } max;
+ u16 wValue;
+ u16 wIndex;
+} snd_evo_ctypes[SND_EVO_TYPE_NCTYPES] = {
+ [SND_EVO_TYPE_MONITOR] = {
+ .type = SNDRV_CTL_ELEM_TYPE_INTEGER,
+ .min.integer = 0,
+ .max.integer = 127,
+ .wValue = 0x0000,
+ .wIndex = 0x3800,
+ },
+ [SND_EVO_TYPE_PHANTOM] = {
+ .type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
+ .invert = false,
+ .min.integer = 0,
+ .max.integer = 1,
+ .wValue = 0x0000,
+ .wIndex = 0x3A00,
+ },
+ [SND_EVO_TYPE_MUTE] = {
+ .type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
+ .invert = true,
+ .min.integer = 0,
+ .max.integer = 1,
+ .wValue = 0x0200,
+ .wIndex = 0x3A00,
+ },
+ [SND_EVO_TYPE_MUTE_OUT] = {
+ .type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
+ .invert = true,
+ .min.integer = 0,
+ .max.integer = 1,
+ .wValue = 0x0100,
+ .wIndex = 0x3B00,
+ },
+ [SND_EVO_TYPE_MIXER] = {
+ .type = SNDRV_CTL_ELEM_TYPE_INTEGER,
+ .min.integer = -128 * 256,
+ .max.integer = 6 * 256,
+ .wValue = 0x0100,
+ .wIndex = 0x3C00,
+ },
+};
+
+#define SND_EVO_FLAGS_DIRECTION (1L<<0)
+#define SND_EVO_FLAGS_CAPTURE (1L<<0)
+#define SND_EVO_FLAGS_PLAYBACK (0L<<0)
+
+struct snd_evo_ctrl {
+ char *basename;
+ enum snd_evo_type type;
+ unsigned int channels;
+ unsigned int hwchannels;
+ unsigned int val_offs;
+ unsigned long flags;
+};
+
+static const struct snd_evo_ctrl evo4_controls[] = {
+ {
+ .basename = "Master",
+ .type = SND_EVO_TYPE_MUTE_OUT,
+ .channels = 1,
+ .hwchannels = 1,
+ .val_offs = 0,
+ .flags = SND_EVO_FLAGS_PLAYBACK,
+ },
+ {
+ .basename = "Mic",
+ .type = SND_EVO_TYPE_MUTE,
+ .channels = 4,
+ .hwchannels = 2,
+ .val_offs = 0,
+ .flags = SND_EVO_FLAGS_PLAYBACK,
+ },
+ {
+ .basename = "Monitor",
+ .type = SND_EVO_TYPE_MONITOR,
+ .channels = 1,
+ .hwchannels = 1,
+ .val_offs = 0,
+ .flags = SND_EVO_FLAGS_PLAYBACK,
+ },
+ {
+ .basename = "Mic 1",
+ .type = SND_EVO_TYPE_MIXER,
+ .channels = 2,
+ .hwchannels = 2,
+ .val_offs = 0,
+ .flags = SND_EVO_FLAGS_CAPTURE,
+ },
+ {
+ .basename = "Mic 2",
+ .type = SND_EVO_TYPE_MIXER,
+ .channels = 2,
+ .hwchannels = 2,
+ .val_offs = 2,
+ .flags = SND_EVO_FLAGS_CAPTURE,
+ },
+ {
+ .basename = "Master Left",
+ .type = SND_EVO_TYPE_MIXER,
+ .channels = 2,
+ .hwchannels = 2,
+ .val_offs = 4,
+ .flags = SND_EVO_FLAGS_CAPTURE,
+ },
+ {
+ .basename = "Master Right",
+ .type = SND_EVO_TYPE_MIXER,
+ .channels = 2,
+ .hwchannels = 2,
+ .val_offs = 6,
+ .flags = SND_EVO_FLAGS_CAPTURE,
+ },
+ {
+ .basename = "Loopback Left",
+ .type = SND_EVO_TYPE_MIXER,
+ .channels = 2,
+ .hwchannels = 2,
+ .val_offs = 8,
+ .flags = SND_EVO_FLAGS_CAPTURE,
+ },
+ {
+ .basename = "Loopback Right",
+ .type = SND_EVO_TYPE_MIXER,
+ .channels = 2,
+ .hwchannels = 2,
+ .val_offs = 10,
+ .flags = SND_EVO_FLAGS_CAPTURE,
+ },
+ {
+ .basename = "Mic 1 Phantom",
+ .type = SND_EVO_TYPE_PHANTOM,
+ .channels = 1,
+ .hwchannels = 1,
+ .val_offs = 0,
+ .flags = SND_EVO_FLAGS_CAPTURE,
+ },
+ {
+ .basename = "Mic 2 Phantom",
+ .type = SND_EVO_TYPE_PHANTOM,
+ .channels = 1,
+ .hwchannels = 1,
+ .val_offs = 1,
+ .flags = SND_EVO_FLAGS_CAPTURE,
+ },
+ { 0 }, /* sentinel */
+};
+
+static const struct evo_devinfo {
+ u32 usb_id;
+ const struct snd_evo_ctrl *controls;
+} evo_devinfo[] = {
+ {
+ .usb_id = USB_ID(USB_AUDIENT_VID, USB_EVO4_PID),
+ .controls = evo4_controls,
+ },
+ {
+ .usb_id = USB_ID(USB_AUDIENT_VID, USB_EVO4_PID),
+ .controls = NULL,
+ },
+ { 0 } /* sentinel */
+};
+
+
+static inline unsigned long snd_evo_kctl_priv(enum snd_evo_type type,
+ u8 valoffs, u8 hwchannels)
+{
+ unsigned long type_l = type & 0xFF;
+ unsigned long valoffs_l = valoffs & 0xFF;
+ unsigned long hwchannels_l = hwchannels & 0xFF;
+
+ return (hwchannels_l << 16) | (valoffs_l << 8) | type_l;
+}
+
+static __always_inline
+const struct snd_evo_ctrl_type *snd_evo_kctl_type(struct snd_kcontrol *kctl)
+{
+ return &snd_evo_ctypes[kctl->private_value & 0xFF];
+}
+
+static __always_inline u16 snd_evo_kctl_valoffs(struct snd_kcontrol *kctl)
+{
+ return (kctl->private_value >> 8) & 0xFF;
+}
+
+static __always_inline u16 snd_evo_kctl_hwchannels(struct snd_kcontrol *kctl)
+{
+ return (kctl->private_value >> 16) & 0xFF;
+}
+
+static inline u16 snd_evo_kctl_channels(struct snd_kcontrol *kctl)
+{
+ struct usb_mixer_elem_info *info = kctl->private_data;
+
+ return info->channels;
+}
+
+
+#define EVO_REQ_CUR (0x01)
+#define EVO_REQTYPE_SET (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE)
+#define EVO_REQTYPE_GET (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE)
+
+static inline int snd_evo_get_cur(struct usb_mixer_interface *mixer,
+ u16 value, u16 index,
+ void *buf, size_t len)
+{
+ struct usb_device *const dev = mixer->chip->dev;
+
+ return snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
+ EVO_REQ_CUR, EVO_REQTYPE_GET,
+ value, index, buf, len);
+}
+
+static inline int snd_evo_set_cur(struct usb_mixer_interface *mixer,
+ u16 value, u16 index,
+ void *buf, size_t len)
+{
+ struct usb_device *const dev = mixer->chip->dev;
+
+ return snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0),
+ EVO_REQ_CUR, EVO_REQTYPE_SET,
+ value, index, buf, len);
+}
+
+
+static int snd_ctl_evo_boolean_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ctl_val)
+{
+ struct usb_mixer_elem_list *const list = snd_kcontrol_chip(kctl);
+ struct usb_mixer_interface *const mixer = list->mixer;
+
+ const unsigned int nchan = snd_evo_kctl_channels(kctl);
+ const unsigned int hwchan = snd_evo_kctl_hwchannels(kctl);
+ const struct snd_evo_ctrl_type *const ctype = snd_evo_kctl_type(kctl);
+ const u16 value = ctype->wValue + snd_evo_kctl_valoffs(kctl);
+ const u16 index = ctype->wIndex;
+
+ int i;
+
+ for (i = 0; i < hwchan; i++) {
+ u32 buf;
+ int ret;
+
+ ret = snd_evo_get_cur(mixer, value + i, index,
+ &buf, sizeof(buf));
+ if (ret < 0)
+ return ret;
+
+ ctl_val->value.integer.value[i] = le32_to_cpu(buf) ? 1 : 0;
+
+ if (ctype->invert)
+ ctl_val->value.integer.value[i] ^= 0x1;
+ }
+
+ for (; i < nchan; i++)
+ ctl_val->value.integer.value[i] = ctype->invert
+ ? ctype->max.integer
+ : ctype->min.integer;
+
+ return 0;
+}
+
+static int snd_ctl_evo_boolean_set(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ctl_val)
+{
+ struct usb_mixer_elem_list *list = snd_kcontrol_chip(kctl);
+ struct usb_mixer_interface *mixer = list->mixer;
+
+ const unsigned int hwchan = snd_evo_kctl_hwchannels(kctl);
+ const struct snd_evo_ctrl_type *const ctype = snd_evo_kctl_type(kctl);
+ const u16 value = ctype->wValue + snd_evo_kctl_valoffs(kctl);
+ const u16 index = ctype->wIndex;
+
+ int changed = 0;
+ int i;
+
+ for (i = 0; i < hwchan; i++) {
+ u32 rbuf;
+ u32 buf = cpu_to_le32(ctl_val->value.integer.value[i] ? 1 : 0);
+ int ret;
+
+ if (ctype->invert)
+ buf ^= 0x1;
+
+ ret = snd_evo_get_cur(mixer, value + i, index,
+ &rbuf, sizeof(rbuf));
+ if (ret < 0)
+ return ret;
+
+ if (rbuf != buf) {
+ changed = 1;
+
+ ret = snd_evo_set_cur(mixer, value + i, index,
+ &buf, sizeof(buf));
+ if (ret < 0)
+ return ret;
+ }
+ }
+
+ return changed;
+}
+
+static int snd_ctl_evo_integer_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ctl_val)
+{
+ struct usb_mixer_elem_list *const list = snd_kcontrol_chip(kctl);
+ struct usb_mixer_interface *const mixer = list->mixer;
+
+ const unsigned int nchan = snd_evo_kctl_channels(kctl);
+ const unsigned int hwchan = snd_evo_kctl_hwchannels(kctl);
+ const struct snd_evo_ctrl_type *const ctype = snd_evo_kctl_type(kctl);
+ const u16 value = ctype->wValue + snd_evo_kctl_valoffs(kctl);
+ const u16 index = ctype->wIndex;
+
+ int i;
+
+ for (i = 0; i < hwchan; i++) {
+ u16 buf;
+ s16 val;
+ int ret;
+
+ ret = snd_evo_get_cur(mixer, value + i, index,
+ &buf, sizeof(buf));
+ if (ret < 0)
+ return ret;
+
+ val = le16_to_cpu(buf);
+ ctl_val->value.integer.value[i] = val;
+ }
+
+ for (; i < nchan; i++)
+ ctl_val->value.integer.value[i] = ctype->min.integer;
+
+ return 0;
+}
+
+static int snd_ctl_evo_integer_set(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ctl_val)
+{
+ struct usb_mixer_elem_list *list = snd_kcontrol_chip(kctl);
+ struct usb_mixer_interface *mixer = list->mixer;
+
+ const unsigned int hwchan = snd_evo_kctl_hwchannels(kctl);
+ const struct snd_evo_ctrl_type *const ctype = snd_evo_kctl_type(kctl);
+ const u16 value = ctype->wValue + snd_evo_kctl_valoffs(kctl);
+ const u16 index = ctype->wIndex;
+
+ int changed = 0;
+ int i;
+
+ for (i = 0; i < hwchan; i++) {
+ s16 rbuf;
+ s16 buf = cpu_to_le16(ctl_val->value.integer.value[i]);
+ int ret;
+
+ ret = snd_evo_get_cur(mixer, value + i, index,
+ &rbuf, sizeof(rbuf));
+ if (ret < 0)
+ return ret;
+
+ if (rbuf != buf) {
+ changed = 1;
+
+ ret = snd_evo_set_cur(mixer, value + i, index,
+ &buf, sizeof(buf));
+ if (ret < 0)
+ return ret;
+ }
+ }
+
+ return changed;
+}
+
+static int snd_ctl_evo_info(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_info *uinfo)
+{
+ const struct snd_evo_ctrl_type *const ctype = snd_evo_kctl_type(kctl);
+
+ uinfo->type = ctype->type;
+ uinfo->access = SNDRV_CTL_ELEM_ACCESS_READWRITE
+ | SNDRV_CTL_ELEM_ACCESS_VOLATILE;
+ uinfo->count = snd_evo_kctl_channels(kctl);
+ uinfo->value.integer.min = ctype->min.integer;
+ uinfo->value.integer.max = ctype->max.integer;
+ return 0;
+}
+
+
+static int snd_evo_add_ctrl(struct usb_mixer_interface *mixer,
+ const struct snd_evo_ctrl *ctrl)
+{
+ const struct snd_evo_ctrl_type *ctype = &snd_evo_ctypes[ctrl->type];
+ char name[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
+ struct snd_kcontrol_new knew = { 0 };
+ struct snd_kcontrol *kctl;
+ struct usb_mixer_elem_info *elem;
+
+ knew.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
+ knew.name = name;
+ knew.info = snd_ctl_evo_info;
+ knew.private_value = snd_evo_kctl_priv(ctrl->type, ctrl->val_offs,
+ ctrl->hwchannels);
+
+ switch (ctype->type) {
+ case SNDRV_CTL_ELEM_TYPE_INTEGER:
+ knew.get = snd_ctl_evo_integer_get;
+ knew.put = snd_ctl_evo_integer_set;
+ break;
+ case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
+ knew.get = snd_ctl_evo_boolean_get;
+ knew.put = snd_ctl_evo_boolean_set;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ snprintf(name, sizeof(name), "%s %s %s", ctrl->basename,
+ ((ctrl->flags & SND_EVO_FLAGS_DIRECTION)
+ == SND_EVO_FLAGS_CAPTURE) ? "Capture" : "Playback",
+ (ctype->type == SNDRV_CTL_ELEM_TYPE_BOOLEAN)
+ ? "Switch" : "Volume");
+
+ elem = kzalloc_obj(*elem);
+ if (!elem)
+ return -ENOMEM;
+
+ elem->head.mixer = mixer;
+ elem->channels = ctrl->channels;
+
+ kctl = snd_ctl_new1(&knew, elem);
+ if (!kctl) {
+ kfree(elem);
+ return -ENOMEM;
+ }
+
+ kctl->private_free = snd_usb_mixer_elem_free;
+
+ return snd_usb_mixer_add_control(&elem->head, kctl);
+}
+
+
+/* called from mixer_quirks.c */
+int snd_evo_controls_create(struct usb_mixer_interface *mixer)
+{
+ const struct evo_devinfo *info;
+ const struct snd_evo_ctrl *ctrl;
+
+ for (info = evo_devinfo; info->controls; info++)
+ if (info->usb_id == mixer->chip->usb_id)
+ break;
+
+ if (!info->controls)
+ return -ENODEV;
+
+ for (ctrl = info->controls; ctrl->basename; ctrl++) {
+ const int ret = snd_evo_add_ctrl(mixer, ctrl);
+
+ if (ret < 0)
+ return ret;
+ }
+
+ return 0;
+}
diff --git a/sound/usb/mixer_evo.h b/sound/usb/mixer_evo.h
new file mode 100644
index 000000000000..7fe7e197185c
--- /dev/null
+++ b/sound/usb/mixer_evo.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __USB_MIXER_EVO_H
+#define __USB_MIXER_EVO_H
+
+#include "mixer.h"
+
+#define USB_AUDIENT_VID (0x2708)
+#define USB_EVO4_PID (0x0006)
+
+int snd_evo_controls_create(struct usb_mixer_interface *mixer);
+
+#endif /* __USB_MIXER_EVO_H */
diff --git a/sound/usb/mixer_quirks.c b/sound/usb/mixer_quirks.c
index fc622eb95dc5..1e266fdbbb8e 100644
--- a/sound/usb/mixer_quirks.c
+++ b/sound/usb/mixer_quirks.c
@@ -38,6 +38,7 @@
#include "mixer_scarlett2.h"
#include "mixer_us16x08.h"
#include "mixer_s1810c.h"
+#include "mixer_evo.h"
#include "helper.h"
#include "fcp.h"
@@ -4539,6 +4540,10 @@ int snd_usb_mixer_apply_create_quirk(struct usb_mixer_interface *mixer)
err = snd_fcp_init(mixer);
break;
+ case USB_ID(USB_AUDIENT_VID, USB_EVO4_PID): /* Audient EVO 4 */
+ err = snd_evo_controls_create(mixer);
+ break;
+
case USB_ID(0x041e, 0x323b): /* Creative Sound Blaster E1 */
err = snd_soundblaster_e1_switch_create(mixer);
break;
--
2.55.0