v4.19.13 snapshot.
diff --git a/sound/firewire/dice/dice-hwdep.c b/sound/firewire/dice/dice-hwdep.c
new file mode 100644
index 0000000..6498bf6
--- /dev/null
+++ b/sound/firewire/dice/dice-hwdep.c
@@ -0,0 +1,190 @@
+/*
+ * dice_hwdep.c - a part of driver for DICE based devices
+ *
+ * Copyright (c) Clemens Ladisch <clemens@ladisch.de>
+ * Copyright (c) 2014 Takashi Sakamoto <o-takashi@sakamocchi.jp>
+ *
+ * Licensed under the terms of the GNU General Public License, version 2.
+ */
+
+#include "dice.h"
+
+static long hwdep_read(struct snd_hwdep *hwdep, char __user *buf,
+ long count, loff_t *offset)
+{
+ struct snd_dice *dice = hwdep->private_data;
+ DEFINE_WAIT(wait);
+ union snd_firewire_event event;
+
+ spin_lock_irq(&dice->lock);
+
+ while (!dice->dev_lock_changed && dice->notification_bits == 0) {
+ prepare_to_wait(&dice->hwdep_wait, &wait, TASK_INTERRUPTIBLE);
+ spin_unlock_irq(&dice->lock);
+ schedule();
+ finish_wait(&dice->hwdep_wait, &wait);
+ if (signal_pending(current))
+ return -ERESTARTSYS;
+ spin_lock_irq(&dice->lock);
+ }
+
+ memset(&event, 0, sizeof(event));
+ if (dice->dev_lock_changed) {
+ event.lock_status.type = SNDRV_FIREWIRE_EVENT_LOCK_STATUS;
+ event.lock_status.status = dice->dev_lock_count > 0;
+ dice->dev_lock_changed = false;
+
+ count = min_t(long, count, sizeof(event.lock_status));
+ } else {
+ event.dice_notification.type =
+ SNDRV_FIREWIRE_EVENT_DICE_NOTIFICATION;
+ event.dice_notification.notification = dice->notification_bits;
+ dice->notification_bits = 0;
+
+ count = min_t(long, count, sizeof(event.dice_notification));
+ }
+
+ spin_unlock_irq(&dice->lock);
+
+ if (copy_to_user(buf, &event, count))
+ return -EFAULT;
+
+ return count;
+}
+
+static __poll_t hwdep_poll(struct snd_hwdep *hwdep, struct file *file,
+ poll_table *wait)
+{
+ struct snd_dice *dice = hwdep->private_data;
+ __poll_t events;
+
+ poll_wait(file, &dice->hwdep_wait, wait);
+
+ spin_lock_irq(&dice->lock);
+ if (dice->dev_lock_changed || dice->notification_bits != 0)
+ events = EPOLLIN | EPOLLRDNORM;
+ else
+ events = 0;
+ spin_unlock_irq(&dice->lock);
+
+ return events;
+}
+
+static int hwdep_get_info(struct snd_dice *dice, void __user *arg)
+{
+ struct fw_device *dev = fw_parent_device(dice->unit);
+ struct snd_firewire_get_info info;
+
+ memset(&info, 0, sizeof(info));
+ info.type = SNDRV_FIREWIRE_TYPE_DICE;
+ info.card = dev->card->index;
+ *(__be32 *)&info.guid[0] = cpu_to_be32(dev->config_rom[3]);
+ *(__be32 *)&info.guid[4] = cpu_to_be32(dev->config_rom[4]);
+ strlcpy(info.device_name, dev_name(&dev->device),
+ sizeof(info.device_name));
+
+ if (copy_to_user(arg, &info, sizeof(info)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static int hwdep_lock(struct snd_dice *dice)
+{
+ int err;
+
+ spin_lock_irq(&dice->lock);
+
+ if (dice->dev_lock_count == 0) {
+ dice->dev_lock_count = -1;
+ err = 0;
+ } else {
+ err = -EBUSY;
+ }
+
+ spin_unlock_irq(&dice->lock);
+
+ return err;
+}
+
+static int hwdep_unlock(struct snd_dice *dice)
+{
+ int err;
+
+ spin_lock_irq(&dice->lock);
+
+ if (dice->dev_lock_count == -1) {
+ dice->dev_lock_count = 0;
+ err = 0;
+ } else {
+ err = -EBADFD;
+ }
+
+ spin_unlock_irq(&dice->lock);
+
+ return err;
+}
+
+static int hwdep_release(struct snd_hwdep *hwdep, struct file *file)
+{
+ struct snd_dice *dice = hwdep->private_data;
+
+ spin_lock_irq(&dice->lock);
+ if (dice->dev_lock_count == -1)
+ dice->dev_lock_count = 0;
+ spin_unlock_irq(&dice->lock);
+
+ return 0;
+}
+
+static int hwdep_ioctl(struct snd_hwdep *hwdep, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ struct snd_dice *dice = hwdep->private_data;
+
+ switch (cmd) {
+ case SNDRV_FIREWIRE_IOCTL_GET_INFO:
+ return hwdep_get_info(dice, (void __user *)arg);
+ case SNDRV_FIREWIRE_IOCTL_LOCK:
+ return hwdep_lock(dice);
+ case SNDRV_FIREWIRE_IOCTL_UNLOCK:
+ return hwdep_unlock(dice);
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+
+#ifdef CONFIG_COMPAT
+static int hwdep_compat_ioctl(struct snd_hwdep *hwdep, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ return hwdep_ioctl(hwdep, file, cmd,
+ (unsigned long)compat_ptr(arg));
+}
+#else
+#define hwdep_compat_ioctl NULL
+#endif
+
+int snd_dice_create_hwdep(struct snd_dice *dice)
+{
+ static const struct snd_hwdep_ops ops = {
+ .read = hwdep_read,
+ .release = hwdep_release,
+ .poll = hwdep_poll,
+ .ioctl = hwdep_ioctl,
+ .ioctl_compat = hwdep_compat_ioctl,
+ };
+ struct snd_hwdep *hwdep;
+ int err;
+
+ err = snd_hwdep_new(dice->card, "DICE", 0, &hwdep);
+ if (err < 0)
+ return err;
+ strcpy(hwdep->name, "DICE");
+ hwdep->iface = SNDRV_HWDEP_IFACE_FW_DICE;
+ hwdep->ops = ops;
+ hwdep->private_data = dice;
+ hwdep->exclusive = true;
+
+ return 0;
+}