From 71c3797779d3cd8378767f5b2d8cfd3b2f88c5c1 Mon Sep 17 00:00:00 2001 From: Takashi Sakamoto Date: Wed, 22 Mar 2017 21:30:24 +0900 Subject: ALSA: firewire-motu: add hwdep interface This commit adds hwdep interface so as the other sound drivers for units on IEEE 1394 bus have. This interface is designed for mixer/control applications. By using this interface, an application can get information about firewire node, can lock/unlock kernel streaming and can get notification at starting/stopping kernel streaming. Signed-off-by: Takashi Sakamoto Signed-off-by: Takashi Iwai --- sound/firewire/motu/motu-hwdep.c | 192 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 192 insertions(+) create mode 100644 sound/firewire/motu/motu-hwdep.c (limited to 'sound/firewire/motu/motu-hwdep.c') diff --git a/sound/firewire/motu/motu-hwdep.c b/sound/firewire/motu/motu-hwdep.c new file mode 100644 index 000000000000..e795a5219a21 --- /dev/null +++ b/sound/firewire/motu/motu-hwdep.c @@ -0,0 +1,192 @@ +/* + * motu-hwdep.c - a part of driver for MOTU FireWire series + * + * Copyright (c) 2015-2017 Takashi Sakamoto + * + * Licensed under the terms of the GNU General Public License, version 2. + */ + +/* + * This codes have five functionalities. + * + * 1.get information about firewire node + * 2.get notification about starting/stopping stream + * 3.lock/unlock streaming + * + */ + +#include "motu.h" + +static long hwdep_read(struct snd_hwdep *hwdep, char __user *buf, long count, + loff_t *offset) +{ + struct snd_motu *motu = hwdep->private_data; + DEFINE_WAIT(wait); + union snd_firewire_event event; + + spin_lock_irq(&motu->lock); + + while (!motu->dev_lock_changed) { + prepare_to_wait(&motu->hwdep_wait, &wait, TASK_INTERRUPTIBLE); + spin_unlock_irq(&motu->lock); + schedule(); + finish_wait(&motu->hwdep_wait, &wait); + if (signal_pending(current)) + return -ERESTARTSYS; + spin_lock_irq(&motu->lock); + } + + memset(&event, 0, sizeof(event)); + if (motu->dev_lock_changed) { + event.lock_status.type = SNDRV_FIREWIRE_EVENT_LOCK_STATUS; + event.lock_status.status = (motu->dev_lock_count > 0); + motu->dev_lock_changed = false; + + count = min_t(long, count, sizeof(event.lock_status)); + } + + spin_unlock_irq(&motu->lock); + + if (copy_to_user(buf, &event, count)) + return -EFAULT; + + return count; +} + +static unsigned int hwdep_poll(struct snd_hwdep *hwdep, struct file *file, + poll_table *wait) +{ + struct snd_motu *motu = hwdep->private_data; + unsigned int events; + + poll_wait(file, &motu->hwdep_wait, wait); + + spin_lock_irq(&motu->lock); + if (motu->dev_lock_changed) + events = POLLIN | POLLRDNORM; + else + events = 0; + spin_unlock_irq(&motu->lock); + + return events | POLLOUT; +} + +static int hwdep_get_info(struct snd_motu *motu, void __user *arg) +{ + struct fw_device *dev = fw_parent_device(motu->unit); + struct snd_firewire_get_info info; + + memset(&info, 0, sizeof(info)); + info.type = SNDRV_FIREWIRE_TYPE_MOTU; + 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_motu *motu) +{ + int err; + + spin_lock_irq(&motu->lock); + + if (motu->dev_lock_count == 0) { + motu->dev_lock_count = -1; + err = 0; + } else { + err = -EBUSY; + } + + spin_unlock_irq(&motu->lock); + + return err; +} + +static int hwdep_unlock(struct snd_motu *motu) +{ + int err; + + spin_lock_irq(&motu->lock); + + if (motu->dev_lock_count == -1) { + motu->dev_lock_count = 0; + err = 0; + } else { + err = -EBADFD; + } + + spin_unlock_irq(&motu->lock); + + return err; +} + +static int hwdep_release(struct snd_hwdep *hwdep, struct file *file) +{ + struct snd_motu *motu = hwdep->private_data; + + spin_lock_irq(&motu->lock); + if (motu->dev_lock_count == -1) + motu->dev_lock_count = 0; + spin_unlock_irq(&motu->lock); + + return 0; +} + +static int hwdep_ioctl(struct snd_hwdep *hwdep, struct file *file, + unsigned int cmd, unsigned long arg) +{ + struct snd_motu *motu = hwdep->private_data; + + switch (cmd) { + case SNDRV_FIREWIRE_IOCTL_GET_INFO: + return hwdep_get_info(motu, (void __user *)arg); + case SNDRV_FIREWIRE_IOCTL_LOCK: + return hwdep_lock(motu); + case SNDRV_FIREWIRE_IOCTL_UNLOCK: + return hwdep_unlock(motu); + 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_motu_create_hwdep_device(struct snd_motu *motu) +{ + 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(motu->card, motu->card->driver, 0, &hwdep); + if (err < 0) + return err; + + strcpy(hwdep->name, "MOTU"); + hwdep->iface = SNDRV_HWDEP_IFACE_FW_MOTU; + hwdep->ops = ops; + hwdep->private_data = motu; + hwdep->exclusive = true; + + return 0; +} -- cgit