// SPDX-License-Identifier: GPL-2.0-only
/*
* dice_hwdep.c - a part of driver for DICE based devices
*
* Copyright (c) Clemens Ladisch <[email protected]>
* Copyright (c) 2014 Takashi Sakamoto <[email protected]>
*/
#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]);
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_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;
}