[PATCH 10/17] ALSA: usb-audio: scarlett2: Add direct monitor support
Geoffrey D. Bennett
g at b4.vu
Tue Jun 22 19:03:08 CEST 2021
The Solo and 2i2 devices don't have a mixer but they do have a "direct
monitor" switch. Add support for getting and setting the state of this
switch.
Co-developed-by: Vladimir Sadovnikov <sadko4u at gmail.com>
Signed-off-by: Vladimir Sadovnikov <sadko4u at gmail.com>
Signed-off-by: Geoffrey D. Bennett <g at b4.vu>
---
sound/usb/mixer_scarlett_gen2.c | 161 ++++++++++++++++++++++++++++++--
1 file changed, 154 insertions(+), 7 deletions(-)
diff --git a/sound/usb/mixer_scarlett_gen2.c b/sound/usb/mixer_scarlett_gen2.c
index bc4f29cfb2f3..2912854f64c1 100644
--- a/sound/usb/mixer_scarlett_gen2.c
+++ b/sound/usb/mixer_scarlett_gen2.c
@@ -48,7 +48,8 @@
* Support for Solo/2i2 Gen 3 added in May 2021 (thanks to Alexander
* Vorona for 2i2 protocol traces).
*
- * Support for phantom power added in May 2021.
+ * Support for phantom power and direct monitoring added in May-June
+ * 2021.
*
* This ALSA mixer gives access to (model-dependent):
* - input, output, mixer-matrix muxes
@@ -56,7 +57,7 @@
* - gain/volume/mute controls
* - level meters
* - line/inst level, pad, and air controls
- * - phantom power controls
+ * - phantom power and direct monitor controls
* - disable/enable MSD mode
*
* <ditaa>
@@ -338,6 +339,11 @@ struct scarlett2_device_info {
/* the number of inputs each phantom switch controls */
u8 inputs_per_phantom;
+ /* the number of direct monitor options
+ * (0 = none, 1 = mono only, 2 = mono/stereo)
+ */
+ u8 direct_monitor;
+
/* additional description for the line out volume controls */
const char * const line_out_descrs[SCARLETT2_ANALOGUE_MAX];
@@ -365,6 +371,7 @@ struct scarlett2_data {
u8 sync_updated;
u8 vol_updated;
u8 input_other_updated;
+ u8 monitor_other_updated;
u8 sync;
u8 master_vol;
u8 vol[SCARLETT2_ANALOGUE_MAX];
@@ -376,6 +383,7 @@ struct scarlett2_data {
u8 air_switch[SCARLETT2_AIR_SWITCH_MAX];
u8 phantom_switch[SCARLETT2_PHANTOM_SWITCH_MAX];
u8 phantom_persistence;
+ u8 direct_monitor_switch;
u8 msd_switch;
struct snd_kcontrol *sync_ctl;
struct snd_kcontrol *master_vol_ctl;
@@ -386,6 +394,7 @@ struct scarlett2_data {
struct snd_kcontrol *pad_ctls[SCARLETT2_PAD_SWITCH_MAX];
struct snd_kcontrol *air_ctls[SCARLETT2_AIR_SWITCH_MAX];
struct snd_kcontrol *phantom_ctls[SCARLETT2_PHANTOM_SWITCH_MAX];
+ struct snd_kcontrol *direct_monitor_ctl;
u8 mux[SCARLETT2_MUX_MAX];
u8 mix[SCARLETT2_INPUT_MIX_MAX * SCARLETT2_OUTPUT_MIX_MAX];
};
@@ -550,6 +559,7 @@ static const struct scarlett2_device_info solo_gen3_info = {
.air_input_count = 1,
.phantom_count = 1,
.inputs_per_phantom = 1,
+ .direct_monitor = 1,
};
static const struct scarlett2_device_info s2i2_gen3_info = {
@@ -560,6 +570,7 @@ static const struct scarlett2_device_info s2i2_gen3_info = {
.air_input_count = 2,
.phantom_count = 1,
.inputs_per_phantom = 2,
+ .direct_monitor = 2,
};
static const struct scarlett2_device_info s4i4_gen3_info = {
@@ -824,10 +835,11 @@ static int scarlett2_get_port_start_num(
/*** USB Interactions ***/
/* Notifications from the interface */
-#define SCARLETT2_USB_NOTIFY_SYNC 0x00000008
-#define SCARLETT2_USB_NOTIFY_DIM_MUTE 0x00200000
-#define SCARLETT2_USB_NOTIFY_MONITOR 0x00400000
-#define SCARLETT2_USB_NOTIFY_INPUT_OTHER 0x00800000
+#define SCARLETT2_USB_NOTIFY_SYNC 0x00000008
+#define SCARLETT2_USB_NOTIFY_DIM_MUTE 0x00200000
+#define SCARLETT2_USB_NOTIFY_MONITOR 0x00400000
+#define SCARLETT2_USB_NOTIFY_INPUT_OTHER 0x00800000
+#define SCARLETT2_USB_NOTIFY_MONITOR_OTHER 0x01000000
/* Commands for sending/receiving requests/responses */
#define SCARLETT2_USB_CMD_INIT 0
@@ -888,7 +900,8 @@ enum {
SCARLETT2_CONFIG_AIR_SWITCH = 7,
SCARLETT2_CONFIG_PHANTOM_SWITCH = 8,
SCARLETT2_CONFIG_PHANTOM_PERSISTENCE = 9,
- SCARLETT2_CONFIG_COUNT = 10
+ SCARLETT2_CONFIG_DIRECT_MONITOR = 10,
+ SCARLETT2_CONFIG_COUNT = 11
};
/* Location, size, and activation command number for the configuration
@@ -917,6 +930,9 @@ static const struct scarlett2_config
[SCARLETT2_CONFIG_PHANTOM_SWITCH] = {
.offset = 0x06, .size = 8, .activate = 3 },
+ [SCARLETT2_CONFIG_DIRECT_MONITOR] = {
+ .offset = 0x07, .size = 8, .activate = 4 },
+
[SCARLETT2_CONFIG_LEVEL_SWITCH] = {
.offset = 0x08, .size = 1, .activate = 7 },
@@ -2270,6 +2286,112 @@ static const struct snd_kcontrol_new scarlett2_phantom_persistence_ctl = {
.put = scarlett2_phantom_persistence_ctl_put,
};
+/*** Direct Monitor Control ***/
+
+static int scarlett2_update_monitor_other(struct usb_mixer_interface *mixer)
+{
+ struct scarlett2_data *private = mixer->private_data;
+ const struct scarlett2_device_info *info = private->info;
+
+ private->monitor_other_updated = 0;
+
+ if (info->direct_monitor)
+ return scarlett2_usb_get_config(
+ mixer, SCARLETT2_CONFIG_DIRECT_MONITOR,
+ 1, &private->direct_monitor_switch);
+
+ return 0;
+}
+
+static int scarlett2_direct_monitor_ctl_get(
+ struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
+{
+ struct usb_mixer_elem_info *elem = kctl->private_data;
+ struct usb_mixer_interface *mixer = elem->head.mixer;
+ struct scarlett2_data *private = elem->head.mixer->private_data;
+
+ mutex_lock(&private->data_mutex);
+ if (private->monitor_other_updated)
+ scarlett2_update_monitor_other(mixer);
+ ucontrol->value.enumerated.item[0] = private->direct_monitor_switch;
+ mutex_unlock(&private->data_mutex);
+
+ return 0;
+}
+
+static int scarlett2_direct_monitor_ctl_put(
+ struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
+{
+ struct usb_mixer_elem_info *elem = kctl->private_data;
+ struct usb_mixer_interface *mixer = elem->head.mixer;
+ struct scarlett2_data *private = mixer->private_data;
+
+ int index = elem->control;
+ int oval, val, err = 0;
+
+ mutex_lock(&private->data_mutex);
+
+ oval = private->direct_monitor_switch;
+ val = min(ucontrol->value.enumerated.item[0], 2U);
+
+ if (oval == val)
+ goto unlock;
+
+ private->direct_monitor_switch = val;
+
+ /* Send switch change to the device */
+ err = scarlett2_usb_set_config(
+ mixer, SCARLETT2_CONFIG_DIRECT_MONITOR, index, val);
+
+unlock:
+ mutex_unlock(&private->data_mutex);
+ return err;
+}
+
+static int scarlett2_direct_monitor_stereo_enum_ctl_info(
+ struct snd_kcontrol *kctl, struct snd_ctl_elem_info *uinfo)
+{
+ static const char *const values[3] = {
+ "Off", "Mono", "Stereo"
+ };
+
+ return snd_ctl_enum_info(uinfo, 1, 3, values);
+}
+
+/* Direct Monitor for Solo is mono-only and only needs a boolean control
+ * Direct Monitor for 2i2 is selectable between Off/Mono/Stereo
+ */
+static const struct snd_kcontrol_new scarlett2_direct_monitor_ctl[2] = {
+ {
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "",
+ .info = snd_ctl_boolean_mono_info,
+ .get = scarlett2_direct_monitor_ctl_get,
+ .put = scarlett2_direct_monitor_ctl_put,
+ },
+ {
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "",
+ .info = scarlett2_direct_monitor_stereo_enum_ctl_info,
+ .get = scarlett2_direct_monitor_ctl_get,
+ .put = scarlett2_direct_monitor_ctl_put,
+ }
+};
+
+static int scarlett2_add_direct_monitor_ctl(struct usb_mixer_interface *mixer)
+{
+ struct scarlett2_data *private = mixer->private_data;
+ const struct scarlett2_device_info *info = private->info;
+
+ if (!info->direct_monitor)
+ return 0;
+
+ return scarlett2_add_new_ctl(
+ mixer, &scarlett2_direct_monitor_ctl[info->direct_monitor - 1],
+ 0, 1, "Direct Monitor Playback Switch",
+ &private->direct_monitor_ctl);
+}
+
/*** Dim/Mute Controls ***/
static int scarlett2_dim_mute_ctl_get(struct snd_kcontrol *kctl,
@@ -2988,6 +3110,10 @@ static int scarlett2_read_configs(struct usb_mixer_interface *mixer)
if (err < 0)
return err;
+ err = scarlett2_update_monitor_other(mixer);
+ if (err < 0)
+ return err;
+
/* the rest of the configuration is for devices with a mixer */
if (!info->has_mixer)
return 0;
@@ -3129,6 +3255,20 @@ static void scarlett2_notify_input_other(
&private->phantom_ctls[i]->id);
}
+/* Notify on "monitor other" change (direct monitor) */
+static void scarlett2_notify_monitor_other(
+ struct usb_mixer_interface *mixer)
+{
+ struct scarlett2_data *private = mixer->private_data;
+ struct snd_card *card = mixer->chip->card;
+
+ private->monitor_other_updated = 1;
+
+ if (private->info->direct_monitor)
+ snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
+ &private->direct_monitor_ctl->id);
+}
+
/* Interrupt callback */
static void scarlett2_notify(struct urb *urb)
{
@@ -3149,6 +3289,8 @@ static void scarlett2_notify(struct urb *urb)
scarlett2_notify_dim_mute(mixer);
if (data & SCARLETT2_USB_NOTIFY_INPUT_OTHER)
scarlett2_notify_input_other(mixer);
+ if (data & SCARLETT2_USB_NOTIFY_MONITOR_OTHER)
+ scarlett2_notify_monitor_other(mixer);
requeue:
if (ustatus != -ENOENT &&
@@ -3255,6 +3397,11 @@ static int snd_scarlett_gen2_controls_create(struct usb_mixer_interface *mixer)
if (err < 0)
return err;
+ /* Create the direct monitor control */
+ err = scarlett2_add_direct_monitor_ctl(mixer);
+ if (err < 0)
+ return err;
+
/* Set up the interrupt polling */
err = scarlett2_init_notify(mixer);
if (err < 0)
--
2.31.1
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