[PATCH 10/11] ALSA: scarlett2: Add ioctl commands to erase flash segments

["Geoffrey D. Bennett" <g@b4.vu>]

Add ioctls:
- SCARLETT2_IOCTL_SELECT_FLASH_SEGMENT
- SCARLETT2_IOCTL_ERASE_FLASH_SEGMENT
- SCARLETT2_IOCTL_GET_ERASE_PROGRESS

The settings or the firmware flash segment can be selected and then
erased (asynchronous operation), and the erase progress can be
monitored.

If the erase progress is not monitored, then subsequent hwdep
operations will block until the erase is complete.

Once the erase is started, ALSA controls that communicate with the
device will all return -EBUSY, and the device must be rebooted.

Signed-off-by: Geoffrey D. Bennett <g@b4.vu>
---
 include/uapi/sound/scarlett2.h |  20 ++
 sound/usb/mixer_scarlett2.c    | 428 ++++++++++++++++++++++++++++++++-
 2 files changed, 442 insertions(+), 6 deletions(-)

diff --git a/include/uapi/sound/scarlett2.h b/include/uapi/sound/scarlett2.h
index ec0b7da335ff..d0ff38ffa154 100644
--- a/include/uapi/sound/scarlett2.h
+++ b/include/uapi/sound/scarlett2.h
@@ -31,4 +31,24 @@
 /* Reboot */
 #define SCARLETT2_IOCTL_REBOOT _IO('S', 0x61)
 
+/* Select flash segment */
+#define SCARLETT2_SEGMENT_ID_SETTINGS 0
+#define SCARLETT2_SEGMENT_ID_FIRMWARE 1
+#define SCARLETT2_SEGMENT_ID_COUNT 2
+
+#define SCARLETT2_IOCTL_SELECT_FLASH_SEGMENT _IOW('S', 0x62, int)
+
+/* Erase selected flash segment */
+#define SCARLETT2_IOCTL_ERASE_FLASH_SEGMENT _IO('S', 0x63)
+
+/* Get selected flash segment erase progress
+ * 1 through to num_blocks, or 255 for complete
+ */
+struct scarlett2_flash_segment_erase_progress {
+	unsigned char progress;
+	unsigned char num_blocks;
+};
+#define SCARLETT2_IOCTL_GET_ERASE_PROGRESS \
+	_IOR('S', 0x64, struct scarlett2_flash_segment_erase_progress)
+
 #endif /* __UAPI_SOUND_SCARLETT2_H */
diff --git a/sound/usb/mixer_scarlett2.c b/sound/usb/mixer_scarlett2.c
index c0c96d7c19fb..ca09d0cd0cae 100644
--- a/sound/usb/mixer_scarlett2.c
+++ b/sound/usb/mixer_scarlett2.c
@@ -193,11 +193,6 @@ static const u16 scarlett2_mixer_values[SCARLETT2_MIXER_VALUE_COUNT] = {
 	16345
 };
 
-/* Flash segments that we may manipulate */
-#define SCARLETT2_SEGMENT_ID_SETTINGS 0
-#define SCARLETT2_SEGMENT_ID_FIRMWARE 1
-#define SCARLETT2_SEGMENT_ID_COUNT 2
-
 /* Maximum number of analogue outputs */
 #define SCARLETT2_ANALOGUE_MAX 10
 
@@ -267,6 +262,13 @@ enum {
 	SCARLETT2_DIM_MUTE_COUNT = 2,
 };
 
+/* Flash Write State */
+enum {
+	SCARLETT2_FLASH_WRITE_STATE_IDLE = 0,
+	SCARLETT2_FLASH_WRITE_STATE_SELECTED = 1,
+	SCARLETT2_FLASH_WRITE_STATE_ERASING = 2
+};
+
 static const char *const scarlett2_dim_mute_names[SCARLETT2_DIM_MUTE_COUNT] = {
 	"Mute Playback Switch", "Dim Playback Switch"
 };
@@ -427,6 +429,9 @@ struct scarlett2_data {
 	struct usb_mixer_interface *mixer;
 	struct mutex usb_mutex; /* prevent sending concurrent USB requests */
 	struct mutex data_mutex; /* lock access to this data */
+	u8 hwdep_in_use;
+	u8 selected_flash_segment_id;
+	u8 flash_write_state;
 	struct delayed_work work;
 	const struct scarlett2_device_info *info;
 	const char *series_name;
@@ -2137,6 +2142,11 @@ static int scarlett2_sync_ctl_get(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	if (private->sync_updated) {
 		err = scarlett2_update_sync(mixer);
 		if (err < 0)
@@ -2233,6 +2243,11 @@ static int scarlett2_master_volume_ctl_get(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	if (private->vol_updated) {
 		err = scarlett2_update_volumes(mixer);
 		if (err < 0)
@@ -2272,6 +2287,11 @@ static int scarlett2_volume_ctl_get(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	if (private->vol_updated) {
 		err = scarlett2_update_volumes(mixer);
 		if (err < 0)
@@ -2295,6 +2315,11 @@ static int scarlett2_volume_ctl_put(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	oval = private->vol[index];
 	val = ucontrol->value.integer.value[0];
 
@@ -2352,6 +2377,11 @@ static int scarlett2_mute_ctl_get(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	if (private->vol_updated) {
 		err = scarlett2_update_volumes(mixer);
 		if (err < 0)
@@ -2375,6 +2405,11 @@ static int scarlett2_mute_ctl_put(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	oval = private->mute_switch[index];
 	val = !!ucontrol->value.integer.value[0];
 
@@ -2514,6 +2549,11 @@ static int scarlett2_sw_hw_enum_ctl_put(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	oval = private->vol_sw_hw_switch[index];
 	val = !!ucontrol->value.enumerated.item[0];
 
@@ -2611,6 +2651,11 @@ static int scarlett2_level_enum_ctl_get(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	if (private->input_other_updated) {
 		err = scarlett2_update_input_other(mixer);
 		if (err < 0)
@@ -2636,6 +2681,11 @@ static int scarlett2_level_enum_ctl_put(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	oval = private->level_switch[index];
 	val = !!ucontrol->value.enumerated.item[0];
 
@@ -2675,6 +2725,11 @@ static int scarlett2_pad_ctl_get(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	if (private->input_other_updated) {
 		err = scarlett2_update_input_other(mixer);
 		if (err < 0)
@@ -2700,6 +2755,11 @@ static int scarlett2_pad_ctl_put(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	oval = private->pad_switch[index];
 	val = !!ucontrol->value.integer.value[0];
 
@@ -2739,6 +2799,11 @@ static int scarlett2_air_ctl_get(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	if (private->input_other_updated) {
 		err = scarlett2_update_input_other(mixer);
 		if (err < 0)
@@ -2763,6 +2828,11 @@ static int scarlett2_air_ctl_put(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	oval = private->air_switch[index];
 	val = !!ucontrol->value.integer.value[0];
 
@@ -2802,6 +2872,11 @@ static int scarlett2_phantom_ctl_get(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	if (private->input_other_updated) {
 		err = scarlett2_update_input_other(mixer);
 		if (err < 0)
@@ -2827,6 +2902,11 @@ static int scarlett2_phantom_ctl_put(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	oval = private->phantom_switch[index];
 	val = !!ucontrol->value.integer.value[0];
 
@@ -2878,6 +2958,11 @@ static int scarlett2_phantom_persistence_ctl_put(
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	oval = private->phantom_persistence;
 	val = !!ucontrol->value.integer.value[0];
 
@@ -2988,6 +3073,11 @@ static int scarlett2_direct_monitor_ctl_get(
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	if (private->monitor_other_updated) {
 		err = scarlett2_update_monitor_other(mixer);
 		if (err < 0)
@@ -3012,6 +3102,11 @@ static int scarlett2_direct_monitor_ctl_put(
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	oval = private->direct_monitor_switch;
 	val = min(ucontrol->value.enumerated.item[0], 2U);
 
@@ -3101,6 +3196,11 @@ static int scarlett2_speaker_switch_enum_ctl_get(
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	if (private->monitor_other_updated) {
 		err = scarlett2_update_monitor_other(mixer);
 		if (err < 0)
@@ -3181,6 +3281,11 @@ static int scarlett2_speaker_switch_enum_ctl_put(
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	oval = private->speaker_switching_switch;
 	val = min(ucontrol->value.enumerated.item[0], 2U);
 
@@ -3262,6 +3367,11 @@ static int scarlett2_talkback_enum_ctl_get(
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	if (private->monitor_other_updated) {
 		err = scarlett2_update_monitor_other(mixer);
 		if (err < 0)
@@ -3285,6 +3395,11 @@ static int scarlett2_talkback_enum_ctl_put(
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	oval = private->talkback_switch;
 	val = min(ucontrol->value.enumerated.item[0], 2U);
 
@@ -3349,6 +3464,11 @@ static int scarlett2_talkback_map_ctl_put(
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	oval = private->talkback_map[index];
 	val = !!ucontrol->value.integer.value[0];
 
@@ -3423,6 +3543,11 @@ static int scarlett2_dim_mute_ctl_get(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	if (private->vol_updated) {
 		err = scarlett2_update_volumes(mixer);
 		if (err < 0)
@@ -3451,6 +3576,11 @@ static int scarlett2_dim_mute_ctl_put(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	oval = private->dim_mute[index];
 	val = !!ucontrol->value.integer.value[0];
 
@@ -3695,6 +3825,11 @@ static int scarlett2_mixer_ctl_put(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	oval = private->mix[index];
 	val = clamp(ucontrol->value.integer.value[0],
 		    0L, (long)SCARLETT2_MIXER_MAX_VALUE);
@@ -3808,6 +3943,11 @@ static int scarlett2_mux_src_enum_ctl_get(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	if (private->mux_updated) {
 		err = scarlett2_usb_get_mux(mixer);
 		if (err < 0)
@@ -3831,6 +3971,11 @@ static int scarlett2_mux_src_enum_ctl_put(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	oval = private->mux[index];
 	val = min(ucontrol->value.enumerated.item[0],
 		  private->num_mux_srcs - 1U);
@@ -3915,6 +4060,11 @@ static int scarlett2_meter_ctl_get(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	err = scarlett2_usb_get_meter_levels(elem->head.mixer, elem->channels,
 					     meter_levels);
 	if (err < 0)
@@ -3983,6 +4133,11 @@ static int scarlett2_msd_ctl_put(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	oval = private->msd_switch;
 	val = !!ucontrol->value.integer.value[0];
 
@@ -4050,6 +4205,11 @@ static int scarlett2_standalone_ctl_put(struct snd_kcontrol *kctl,
 
 	mutex_lock(&private->data_mutex);
 
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
 	oval = private->standalone_switch;
 	val = !!ucontrol->value.integer.value[0];
 
@@ -4712,12 +4872,241 @@ static int snd_scarlett2_controls_create(
 
 /*** hwdep interface ***/
 
-/* Reboot the device. */
+/* Set private->hwdep_in_use; prevents access to the ALSA controls
+ * while doing a config erase/firmware upgrade.
+ */
+static void scarlett2_lock(struct scarlett2_data *private)
+{
+	mutex_lock(&private->data_mutex);
+	private->hwdep_in_use = 1;
+	mutex_unlock(&private->data_mutex);
+}
+
+/* Call SCARLETT2_USB_GET_ERASE to get the erase progress */
+static int scarlett2_get_erase_progress(struct usb_mixer_interface *mixer)
+{
+	struct scarlett2_data *private = mixer->private_data;
+	int segment_id, segment_num, err;
+	u8 erase_resp;
+
+	struct {
+		__le32 segment_num;
+		__le32 pad;
+	} __packed erase_req;
+
+	segment_id = private->selected_flash_segment_id;
+	segment_num = private->flash_segment_nums[segment_id];
+
+	if (segment_num < SCARLETT2_SEGMENT_NUM_MIN ||
+	    segment_num > SCARLETT2_SEGMENT_NUM_MAX)
+		return -EFAULT;
+
+	/* Send the erase progress request */
+	erase_req.segment_num = cpu_to_le32(segment_num);
+	erase_req.pad = 0;
+
+	err = scarlett2_usb(mixer, SCARLETT2_USB_GET_ERASE,
+			    &erase_req, sizeof(erase_req),
+			    &erase_resp, sizeof(erase_resp));
+	if (err < 0)
+		return err;
+
+	return erase_resp;
+}
+
+/* Repeatedly call scarlett2_get_erase_progress() until it returns
+ * 0xff (erase complete) or we've waited 10 seconds (it usually takes
+ * <3 seconds).
+ */
+static int scarlett2_wait_for_erase(struct usb_mixer_interface *mixer)
+{
+	int i, err;
+
+	for (i = 0; i < 100; i++) {
+		err = scarlett2_get_erase_progress(mixer);
+		if (err < 0)
+			return err;
+
+		if (err == 0xff)
+			return 0;
+
+		msleep(100);
+	}
+
+	return -ETIMEDOUT;
+}
+
+/* Reboot the device; wait for the erase to complete if one is in
+ * progress.
+ */
 static int scarlett2_reboot(struct usb_mixer_interface *mixer)
 {
+	struct scarlett2_data *private = mixer->private_data;
+
+	if (private->flash_write_state ==
+	      SCARLETT2_FLASH_WRITE_STATE_ERASING) {
+		int err = scarlett2_wait_for_erase(mixer);
+
+		if (err < 0)
+			return err;
+	}
+
 	return scarlett2_usb(mixer, SCARLETT2_USB_REBOOT, NULL, 0, NULL, 0);
 }
 
+/* Select a flash segment for erasing (and possibly writing to) */
+static int scarlett2_ioctl_select_flash_segment(
+	struct usb_mixer_interface *mixer,
+	unsigned long arg)
+{
+	struct scarlett2_data *private = mixer->private_data;
+	int segment_id, segment_num;
+
+	if (get_user(segment_id, (int __user *)arg))
+		return -EFAULT;
+
+	/* Check the segment ID and segment number */
+	if (segment_id < 0 || segment_id >= SCARLETT2_SEGMENT_ID_COUNT)
+		return -EINVAL;
+
+	segment_num = private->flash_segment_nums[segment_id];
+	if (segment_num < SCARLETT2_SEGMENT_NUM_MIN ||
+	    segment_num > SCARLETT2_SEGMENT_NUM_MAX) {
+		usb_audio_err(mixer->chip,
+			      "%s: invalid segment number %d\n",
+			      __func__, segment_id);
+		return -EFAULT;
+	}
+
+	/* If erasing, wait for it to complete */
+	if (private->flash_write_state == SCARLETT2_FLASH_WRITE_STATE_ERASING) {
+		int err = scarlett2_wait_for_erase(mixer);
+
+		if (err < 0)
+			return err;
+	}
+
+	/* Save the selected segment ID and set the state to SELECTED */
+	private->selected_flash_segment_id = segment_id;
+	private->flash_write_state = SCARLETT2_FLASH_WRITE_STATE_SELECTED;
+
+	return 0;
+}
+
+/* Erase the previously-selected flash segment */
+static int scarlett2_ioctl_erase_flash_segment(
+	struct usb_mixer_interface *mixer)
+{
+	struct scarlett2_data *private = mixer->private_data;
+	int segment_id, segment_num, err;
+
+	struct {
+		__le32 segment_num;
+		__le32 pad;
+	} __packed erase_req;
+
+	if (private->flash_write_state != SCARLETT2_FLASH_WRITE_STATE_SELECTED)
+		return -EINVAL;
+
+	segment_id = private->selected_flash_segment_id;
+	segment_num = private->flash_segment_nums[segment_id];
+
+	if (segment_num < SCARLETT2_SEGMENT_NUM_MIN ||
+	    segment_num > SCARLETT2_SEGMENT_NUM_MAX)
+		return -EFAULT;
+
+	/* Prevent access to ALSA controls that access the device from
+	 * here on
+	 */
+	scarlett2_lock(private);
+
+	/* Send the erase request */
+	erase_req.segment_num = cpu_to_le32(segment_num);
+	erase_req.pad = 0;
+
+	err = scarlett2_usb(mixer, SCARLETT2_USB_ERASE_SEGMENT,
+			    &erase_req, sizeof(erase_req),
+			    NULL, 0);
+	if (err < 0)
+		return err;
+
+	/* On success, change the state from SELECTED to ERASING */
+	private->flash_write_state = SCARLETT2_FLASH_WRITE_STATE_ERASING;
+
+	return 0;
+}
+
+/* Get the erase progress from the device */
+static int scarlett2_ioctl_get_erase_progress(
+	struct usb_mixer_interface *mixer,
+	unsigned long arg)
+{
+	struct scarlett2_data *private = mixer->private_data;
+	struct scarlett2_flash_segment_erase_progress progress;
+	int segment_id, segment_num, err;
+	u8 erase_resp;
+
+	struct {
+		__le32 segment_num;
+		__le32 pad;
+	} __packed erase_req;
+
+	/* Check that we're erasing */
+	if (private->flash_write_state != SCARLETT2_FLASH_WRITE_STATE_ERASING)
+		return -EINVAL;
+
+	segment_id = private->selected_flash_segment_id;
+	segment_num = private->flash_segment_nums[segment_id];
+
+	if (segment_num < SCARLETT2_SEGMENT_NUM_MIN ||
+	    segment_num > SCARLETT2_SEGMENT_NUM_MAX)
+		return -EFAULT;
+
+	/* Send the erase progress request */
+	erase_req.segment_num = cpu_to_le32(segment_num);
+	erase_req.pad = 0;
+
+	err = scarlett2_usb(mixer, SCARLETT2_USB_GET_ERASE,
+			    &erase_req, sizeof(erase_req),
+			    &erase_resp, sizeof(erase_resp));
+	if (err < 0)
+		return err;
+
+	progress.progress = erase_resp;
+	progress.num_blocks = private->flash_segment_blocks[segment_id];
+
+	if (copy_to_user((void __user *)arg, &progress, sizeof(progress)))
+		return -EFAULT;
+
+	/* If the erase is complete, change the state from ERASING to
+	 * IDLE.
+	 */
+	if (progress.progress == 0xff)
+		private->flash_write_state = SCARLETT2_FLASH_WRITE_STATE_IDLE;
+
+	return 0;
+}
+
+static int scarlett2_hwdep_open(struct snd_hwdep *hw, struct file *file)
+{
+	struct usb_mixer_interface *mixer = hw->private_data;
+	struct scarlett2_data *private = mixer->private_data;
+
+	/* If erasing, wait for it to complete */
+	if (private->flash_write_state ==
+	      SCARLETT2_FLASH_WRITE_STATE_ERASING) {
+		int err = scarlett2_wait_for_erase(mixer);
+
+		if (err < 0)
+			return err;
+	}
+
+	/* Set the state to IDLE */
+	private->flash_write_state = SCARLETT2_FLASH_WRITE_STATE_IDLE;
+
+	return 0;
+}
+
 static int scarlett2_hwdep_ioctl(struct snd_hwdep *hw, struct file *file,
 				 unsigned int cmd, unsigned long arg)
 {
@@ -4732,11 +5121,36 @@ static int scarlett2_hwdep_ioctl(struct snd_hwdep *hw, struct file *file,
 	case SCARLETT2_IOCTL_REBOOT:
 		return scarlett2_reboot(mixer);
 
+	case SCARLETT2_IOCTL_SELECT_FLASH_SEGMENT:
+		return scarlett2_ioctl_select_flash_segment(mixer, arg);
+
+	case SCARLETT2_IOCTL_ERASE_FLASH_SEGMENT:
+		return scarlett2_ioctl_erase_flash_segment(mixer);
+
+	case SCARLETT2_IOCTL_GET_ERASE_PROGRESS:
+		return scarlett2_ioctl_get_erase_progress(mixer, arg);
+
 	default:
 		return -ENOIOCTLCMD;
 	}
 }
 
+static int scarlett2_hwdep_release(struct snd_hwdep *hw, struct file *file)
+{
+	struct usb_mixer_interface *mixer = hw->private_data;
+	struct scarlett2_data *private = mixer->private_data;
+
+	/* Return from the SELECTED or WRITE state to IDLE.
+	 * The ERASING state is left as-is, and checked on next open.
+	 */
+	if (private &&
+	    private->hwdep_in_use &&
+	    private->flash_write_state != SCARLETT2_FLASH_WRITE_STATE_ERASING)
+		private->flash_write_state = SCARLETT2_FLASH_WRITE_STATE_IDLE;
+
+	return 0;
+}
+
 static int scarlett2_hwdep_init(struct usb_mixer_interface *mixer)
 {
 	struct snd_hwdep *hw;
@@ -4748,7 +5162,9 @@ static int scarlett2_hwdep_init(struct usb_mixer_interface *mixer)
 
 	hw->private_data = mixer;
 	hw->exclusive = 1;
+	hw->ops.open = scarlett2_hwdep_open;
 	hw->ops.ioctl = scarlett2_hwdep_ioctl;
+	hw->ops.release = scarlett2_hwdep_release;
 
 	return 0;
 }
-- 
2.43.0