Add a control to disable the Gen 3 MSD mode so that the full
functionality of the device is available. Don't create the other
controls until MSD mode is disabled.
Signed-off-by: Geoffrey D. Bennett <g@xxxxx>
---
sound/usb/mixer_scarlett_gen2.c | 120 +++++++++++++++++++++++++++++++-
1 file changed, 117 insertions(+), 3 deletions(-)
diff --git a/sound/usb/mixer_scarlett_gen2.c b/sound/usb/mixer_scarlett_gen2.c
index a4f92291b74f..6995d692c6b2 100644
--- a/sound/usb/mixer_scarlett_gen2.c
+++ b/sound/usb/mixer_scarlett_gen2.c
@@ -44,12 +44,13 @@
* interface during driver initialisation added in May 2021 (thanks to
* Vladimir Sadovnikov for figuring out how).
*
- * This ALSA mixer gives access to:
+ * This ALSA mixer gives access to (model-dependent):
* - input, output, mixer-matrix muxes
* - mixer-matrix gain stages
* - gain/volume/mute controls
* - level meters
* - line/inst level and pad controls
+ * - disable/enable MSD mode
*
* <ditaa>
* /--------------\ 18chn 20chn /--------------\
@@ -102,6 +103,14 @@
* \--------------/
* </ditaa>
*
+ * Gen 3 devices have a Mass Storage Device (MSD) mode where a small
+ * disk with registration and driver download information is presented
+ * to the host. To access the full functionality of the device without
+ * proprietary software, MSD mode can be disabled by:
+ * - holding down the 48V button for five seconds while powering on
+ * the device, or
+ * - using this driver and alsamixer to change the "MSD Mode" setting
+ * to Off and power-cycling the device
*/
#include <linux/slab.h>
@@ -120,6 +129,9 @@
/* device_setup value to enable */
#define SCARLETT2_ENABLE 0x01
+/* device_setup value to allow turning MSD mode back on */
+#define SCARLETT2_MSD_ENABLE 0x02
+
/* some gui mixers can't handle negative ctl values */
#define SCARLETT2_VOLUME_BIAS 127
@@ -279,6 +291,12 @@ struct scarlett2_mux_entry {
struct scarlett2_device_info {
u32 usb_id; /* USB device identifier */
+ /* Gen 3 devices have an internal MSD mode switch that needs
+ * to be disabled in order to access the full functionality of
+ * the device.
+ */
+ u8 has_msd_mode;
+
/* line out hw volume is sw controlled */
u8 line_out_hw_vol;
@@ -327,6 +345,7 @@ struct scarlett2_data {
u8 level_switch[SCARLETT2_LEVEL_SWITCH_MAX];
u8 pad_switch[SCARLETT2_PAD_SWITCH_MAX];
u8 dim_mute[SCARLETT2_DIM_MUTE_COUNT];
+ u8 msd_switch;
struct snd_kcontrol *sync_ctl;
struct snd_kcontrol *master_vol_ctl;
struct snd_kcontrol *vol_ctls[SCARLETT2_ANALOGUE_MAX];
@@ -489,6 +508,7 @@ static const struct scarlett2_device_info s18i20_gen2_info = {
static const struct scarlett2_device_info s4i4_gen3_info = {
.usb_id = USB_ID(0x1235, 0x8212),
+ .has_msd_mode = 1,
.level_input_count = 2,
.pad_input_count = 2,
@@ -530,6 +550,7 @@ static const struct scarlett2_device_info s4i4_gen3_info = {
static const struct scarlett2_device_info s8i6_gen3_info = {
.usb_id = USB_ID(0x1235, 0x8213),
+ .has_msd_mode = 1,
.level_input_count = 2,
.pad_input_count = 2,
@@ -578,6 +599,7 @@ static const struct scarlett2_device_info s8i6_gen3_info = {
static const struct scarlett2_device_info s18i8_gen3_info = {
.usb_id = USB_ID(0x1235, 0x8214),
+ .has_msd_mode = 1,
.line_out_hw_vol = 1,
.level_input_count = 2,
.pad_input_count = 2,
@@ -639,6 +661,7 @@ static const struct scarlett2_device_info s18i8_gen3_info = {
static const struct scarlett2_device_info s18i20_gen3_info = {
.usb_id = USB_ID(0x1235, 0x8215),
+ .has_msd_mode = 1,
.line_out_hw_vol = 1,
.level_input_count = 2,
.pad_input_count = 8,
@@ -786,7 +809,8 @@ enum {
SCARLETT2_CONFIG_SW_HW_SWITCH = 3,
SCARLETT2_CONFIG_LEVEL_SWITCH = 4,
SCARLETT2_CONFIG_PAD_SWITCH = 5,
- SCARLETT2_CONFIG_COUNT = 6
+ SCARLETT2_CONFIG_MSD_SWITCH = 6,
+ SCARLETT2_CONFIG_COUNT = 7
};
/* Location, size, and activation command number for the configuration
@@ -817,6 +841,9 @@ static const struct scarlett2_config
[SCARLETT2_CONFIG_PAD_SWITCH] = {
.offset = 0x84, .size = 1, .activate = 8 },
+
+ [SCARLETT2_CONFIG_MSD_SWITCH] = {
+ .offset = 0x9d, .size = 1, .activate = 6 },
};
/* proprietary request/response format */
@@ -1016,7 +1043,8 @@ static int scarlett2_usb_set_config(
return err;
/* Schedule the change to be written to NVRAM */
- schedule_delayed_work(&private->work, msecs_to_jiffies(2000));
+ if (config_item->activate != SCARLETT2_USB_CONFIG_SAVE)
+ schedule_delayed_work(&private->work, msecs_to_jiffies(2000));
return 0;
}
@@ -2346,6 +2374,71 @@ static int scarlett2_add_meter_ctl(struct usb_mixer_interface *mixer)
"Level Meter", NULL);
}
+/*** MSD Controls ***/
+
+static int scarlett2_msd_ctl_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct usb_mixer_elem_info *elem = kctl->private_data;
+ struct scarlett2_data *private = elem->head.mixer->private_data;
+
+ ucontrol->value.integer.value[0] = private->msd_switch;
+ return 0;
+}
+
+static int scarlett2_msd_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 oval, val, err = 0;
+
+ mutex_lock(&private->data_mutex);
+
+ oval = private->msd_switch;
+ val = !!ucontrol->value.integer.value[0];
+
+ if (oval == val)
+ goto unlock;
+
+ private->msd_switch = val;
+
+ /* Send switch change to the device */
+ err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_MSD_SWITCH,
+ 0, val);
+
+unlock:
+ mutex_unlock(&private->data_mutex);
+ return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_msd_ctl = {
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "",
+ .info = snd_ctl_boolean_mono_info,
+ .get = scarlett2_msd_ctl_get,
+ .put = scarlett2_msd_ctl_put,
+};
+
+static int scarlett2_add_msd_ctl(struct usb_mixer_interface *mixer)
+{
+ struct scarlett2_data *private = mixer->private_data;
+ const struct scarlett2_device_info *info = private->info;
+
+ if (!info->has_msd_mode)
+ return 0;
+
+ /* If MSD mode is off, hide the switch by default */
+ if (!private->msd_switch && !(mixer->chip->setup & SCARLETT2_MSD_ENABLE))
+ return 0;
+
+ /* Add MSD control */
+ return scarlett2_add_new_ctl(mixer, &scarlett2_msd_ctl,
+ 0, 1, "MSD Mode", NULL);
+}
+
/*** Cleanup/Suspend Callbacks ***/
static void scarlett2_private_free(struct usb_mixer_interface *mixer)
@@ -2483,6 +2576,18 @@ static int scarlett2_read_configs(struct usb_mixer_interface *mixer)
struct scarlett2_usb_volume_status volume_status;
int err, i;
+ if (info->has_msd_mode) {
+ err = scarlett2_usb_get_config(
+ mixer, SCARLETT2_CONFIG_MSD_SWITCH,
+ 1, &private->msd_switch);
+ if (err < 0)
+ return err;
+
+ /* no other controls are created if MSD mode is on */
+ if (private->msd_switch)
+ return 0;
+ }
+
err = scarlett2_update_input_other(mixer);
if (err < 0)
return err;
@@ -2705,6 +2810,15 @@ static int snd_scarlett_gen2_controls_create(struct usb_mixer_interface *mixer)
if (err < 0)
return err;
+ /* Create the MSD control */
+ err = scarlett2_add_msd_ctl(mixer);
+ if (err < 0)
+ return err;
+
+ /* If MSD mode is enabled, don't create any other controls */
+ if (((struct scarlett2_data *)mixer->private_data)->msd_switch)
+ return 0;
+
/* Create the analogue output controls */
err = scarlett2_add_line_out_ctls(mixer);
if (err < 0)
--
2.31.1
