From 8985f4ac1c42bd25799f294f4e87fa73064673c7 Mon Sep 17 00:00:00 2001 From: Takashi Sakamoto Date: Tue, 9 Dec 2014 00:10:49 +0900 Subject: ALSA: oxfw: Add hwdep interface This interface is designed for mixer/control application. 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 Acked-by: Clemens Ladisch Signed-off-by: Takashi Iwai --- sound/firewire/oxfw/oxfw-hwdep.c | 190 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 190 insertions(+) create mode 100644 sound/firewire/oxfw/oxfw-hwdep.c (limited to 'sound/firewire/oxfw/oxfw-hwdep.c') diff --git a/sound/firewire/oxfw/oxfw-hwdep.c b/sound/firewire/oxfw/oxfw-hwdep.c new file mode 100644 index 000000000000..ff2687ad0460 --- /dev/null +++ b/sound/firewire/oxfw/oxfw-hwdep.c @@ -0,0 +1,190 @@ +/* + * oxfw_hwdep.c - a part of driver for OXFW970/971 based devices + * + * Copyright (c) 2014 Takashi Sakamoto + * + * Licensed under the terms of the GNU General Public License, version 2. + */ + +/* + * This codes give three functionality. + * + * 1.get firewire node information + * 2.get notification about starting/stopping stream + * 3.lock/unlock stream + */ + +#include "oxfw.h" + +static long hwdep_read(struct snd_hwdep *hwdep, char __user *buf, long count, + loff_t *offset) +{ + struct snd_oxfw *oxfw = hwdep->private_data; + DEFINE_WAIT(wait); + union snd_firewire_event event; + + spin_lock_irq(&oxfw->lock); + + while (!oxfw->dev_lock_changed) { + prepare_to_wait(&oxfw->hwdep_wait, &wait, TASK_INTERRUPTIBLE); + spin_unlock_irq(&oxfw->lock); + schedule(); + finish_wait(&oxfw->hwdep_wait, &wait); + if (signal_pending(current)) + return -ERESTARTSYS; + spin_lock_irq(&oxfw->lock); + } + + memset(&event, 0, sizeof(event)); + if (oxfw->dev_lock_changed) { + event.lock_status.type = SNDRV_FIREWIRE_EVENT_LOCK_STATUS; + event.lock_status.status = (oxfw->dev_lock_count > 0); + oxfw->dev_lock_changed = false; + + count = min_t(long, count, sizeof(event.lock_status)); + } + + spin_unlock_irq(&oxfw->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_oxfw *oxfw = hwdep->private_data; + unsigned int events; + + poll_wait(file, &oxfw->hwdep_wait, wait); + + spin_lock_irq(&oxfw->lock); + if (oxfw->dev_lock_changed) + events = POLLIN | POLLRDNORM; + else + events = 0; + spin_unlock_irq(&oxfw->lock); + + return events; +} + +static int hwdep_get_info(struct snd_oxfw *oxfw, void __user *arg) +{ + struct fw_device *dev = fw_parent_device(oxfw->unit); + struct snd_firewire_get_info info; + + memset(&info, 0, sizeof(info)); + info.type = SNDRV_FIREWIRE_TYPE_OXFW; + 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_oxfw *oxfw) +{ + int err; + + spin_lock_irq(&oxfw->lock); + + if (oxfw->dev_lock_count == 0) { + oxfw->dev_lock_count = -1; + err = 0; + } else { + err = -EBUSY; + } + + spin_unlock_irq(&oxfw->lock); + + return err; +} + +static int hwdep_unlock(struct snd_oxfw *oxfw) +{ + int err; + + spin_lock_irq(&oxfw->lock); + + if (oxfw->dev_lock_count == -1) { + oxfw->dev_lock_count = 0; + err = 0; + } else { + err = -EBADFD; + } + + spin_unlock_irq(&oxfw->lock); + + return err; +} + +static int hwdep_release(struct snd_hwdep *hwdep, struct file *file) +{ + struct snd_oxfw *oxfw = hwdep->private_data; + + spin_lock_irq(&oxfw->lock); + if (oxfw->dev_lock_count == -1) + oxfw->dev_lock_count = 0; + spin_unlock_irq(&oxfw->lock); + + return 0; +} + +static int hwdep_ioctl(struct snd_hwdep *hwdep, struct file *file, + unsigned int cmd, unsigned long arg) +{ + struct snd_oxfw *oxfw = hwdep->private_data; + + switch (cmd) { + case SNDRV_FIREWIRE_IOCTL_GET_INFO: + return hwdep_get_info(oxfw, (void __user *)arg); + case SNDRV_FIREWIRE_IOCTL_LOCK: + return hwdep_lock(oxfw); + case SNDRV_FIREWIRE_IOCTL_UNLOCK: + return hwdep_unlock(oxfw); + 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_oxfw_create_hwdep(struct snd_oxfw *oxfw) +{ + static const struct snd_hwdep_ops hwdep_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(oxfw->card, oxfw->card->driver, 0, &hwdep); + if (err < 0) + goto end; + strcpy(hwdep->name, oxfw->card->driver); + hwdep->iface = SNDRV_HWDEP_IFACE_FW_OXFW; + hwdep->ops = hwdep_ops; + hwdep->private_data = oxfw; + hwdep->exclusive = true; +end: + return err; +} -- cgit