kernel

linux-6.8.1/sound/firewire/digi00x/digi00x-hwdep.c

@@ -0,0 +1,198 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * digi00x-hwdep.c - a part of driver for Digidesign Digi 002/003 family
+ *
+ * Copyright (c) 2014-2015 Takashi Sakamoto
+ */
+
+/*
+ * This codes give three functionality.
+ *
+ * 1.get firewire node information
+ * 2.get notification about starting/stopping stream
+ * 3.lock/unlock stream
+ * 4.get asynchronous messaging
+ */
+
+#include "digi00x.h"
+
+static long hwdep_read(struct snd_hwdep *hwdep, char __user *buf,  long count,
+		       loff_t *offset)
+{
+	struct snd_dg00x *dg00x = hwdep->private_data;
+	DEFINE_WAIT(wait);
+	union snd_firewire_event event;
+
+	spin_lock_irq(&dg00x->lock);
+
+	while (!dg00x->dev_lock_changed && dg00x->msg == 0) {
+		prepare_to_wait(&dg00x->hwdep_wait, &wait, TASK_INTERRUPTIBLE);
+		spin_unlock_irq(&dg00x->lock);
+		schedule();
+		finish_wait(&dg00x->hwdep_wait, &wait);
+		if (signal_pending(current))
+			return -ERESTARTSYS;
+		spin_lock_irq(&dg00x->lock);
+	}
+
+	memset(&event, 0, sizeof(event));
+	if (dg00x->dev_lock_changed) {
+		event.lock_status.type = SNDRV_FIREWIRE_EVENT_LOCK_STATUS;
+		event.lock_status.status = (dg00x->dev_lock_count > 0);
+		dg00x->dev_lock_changed = false;
+
+		count = min_t(long, count, sizeof(event.lock_status));
+	} else {
+		event.digi00x_message.type =
+					SNDRV_FIREWIRE_EVENT_DIGI00X_MESSAGE;
+		event.digi00x_message.message = dg00x->msg;
+		dg00x->msg = 0;
+
+		count = min_t(long, count, sizeof(event.digi00x_message));
+	}
+
+	spin_unlock_irq(&dg00x->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_dg00x *dg00x = hwdep->private_data;
+	__poll_t events;
+
+	poll_wait(file, &dg00x->hwdep_wait, wait);
+
+	spin_lock_irq(&dg00x->lock);
+	if (dg00x->dev_lock_changed || dg00x->msg)
+		events = EPOLLIN | EPOLLRDNORM;
+	else
+		events = 0;
+	spin_unlock_irq(&dg00x->lock);
+
+	return events;
+}
+
+static int hwdep_get_info(struct snd_dg00x *dg00x, void __user *arg)
+{
+	struct fw_device *dev = fw_parent_device(dg00x->unit);
+	struct snd_firewire_get_info info;
+
+	memset(&info, 0, sizeof(info));
+	info.type = SNDRV_FIREWIRE_TYPE_DIGI00X;
+	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]);
+	strscpy(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_dg00x *dg00x)
+{
+	int err;
+
+	spin_lock_irq(&dg00x->lock);
+
+	if (dg00x->dev_lock_count == 0) {
+		dg00x->dev_lock_count = -1;
+		err = 0;
+	} else {
+		err = -EBUSY;
+	}
+
+	spin_unlock_irq(&dg00x->lock);
+
+	return err;
+}
+
+static int hwdep_unlock(struct snd_dg00x *dg00x)
+{
+	int err;
+
+	spin_lock_irq(&dg00x->lock);
+
+	if (dg00x->dev_lock_count == -1) {
+		dg00x->dev_lock_count = 0;
+		err = 0;
+	} else {
+		err = -EBADFD;
+	}
+
+	spin_unlock_irq(&dg00x->lock);
+
+	return err;
+}
+
+static int hwdep_release(struct snd_hwdep *hwdep, struct file *file)
+{
+	struct snd_dg00x *dg00x = hwdep->private_data;
+
+	spin_lock_irq(&dg00x->lock);
+	if (dg00x->dev_lock_count == -1)
+		dg00x->dev_lock_count = 0;
+	spin_unlock_irq(&dg00x->lock);
+
+	return 0;
+}
+
+static int hwdep_ioctl(struct snd_hwdep *hwdep, struct file *file,
+	    unsigned int cmd, unsigned long arg)
+{
+	struct snd_dg00x *dg00x = hwdep->private_data;
+
+	switch (cmd) {
+	case SNDRV_FIREWIRE_IOCTL_GET_INFO:
+		return hwdep_get_info(dg00x, (void __user *)arg);
+	case SNDRV_FIREWIRE_IOCTL_LOCK:
+		return hwdep_lock(dg00x);
+	case SNDRV_FIREWIRE_IOCTL_UNLOCK:
+		return hwdep_unlock(dg00x);
+	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_dg00x_create_hwdep_device(struct snd_dg00x *dg00x)
+{
+	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(dg00x->card, "Digi00x", 0, &hwdep);
+	if (err < 0)
+		return err;
+
+	strcpy(hwdep->name, "Digi00x");
+	hwdep->iface = SNDRV_HWDEP_IFACE_FW_DIGI00X;
+	hwdep->ops = ops;
+	hwdep->private_data = dg00x;
+	hwdep->exclusive = true;
+
+	return err;
+}