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Sourcecode: alsa-driver version File versions

hwdep.c

/*
 *  Hardware dependent layer
 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
 *
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

#include <linux/major.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/mutex.h>
#include <sound/core.h>
#include <sound/control.h>
#include <sound/minors.h>
#include <sound/hwdep.h>
#include <sound/info.h>

MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
MODULE_DESCRIPTION("Hardware dependent layer");
MODULE_LICENSE("GPL");

static LIST_HEAD(snd_hwdep_devices);
static DEFINE_MUTEX(register_mutex);

static int snd_hwdep_free(struct snd_hwdep *hwdep);
static int snd_hwdep_dev_free(struct snd_device *device);
static int snd_hwdep_dev_register(struct snd_device *device);
static int snd_hwdep_dev_disconnect(struct snd_device *device);


static struct snd_hwdep *snd_hwdep_search(struct snd_card *card, int device)
{
      struct snd_hwdep *hwdep;

      list_for_each_entry(hwdep, &snd_hwdep_devices, list)
            if (hwdep->card == card && hwdep->device == device)
                  return hwdep;
      return NULL;
}

static loff_t snd_hwdep_llseek(struct file * file, loff_t offset, int orig)
{
      struct snd_hwdep *hw = file->private_data;
      if (hw->ops.llseek)
            return hw->ops.llseek(hw, file, offset, orig);
      return -ENXIO;
}

static ssize_t snd_hwdep_read(struct file * file, char __user *buf,
                        size_t count, loff_t *offset)
{
      struct snd_hwdep *hw = file->private_data;
      if (hw->ops.read)
            return hw->ops.read(hw, buf, count, offset);
      return -ENXIO;    
}

static ssize_t snd_hwdep_write(struct file * file, const char __user *buf,
                         size_t count, loff_t *offset)
{
      struct snd_hwdep *hw = file->private_data;
      if (hw->ops.write)
            return hw->ops.write(hw, buf, count, offset);
      return -ENXIO;    
}

static int snd_hwdep_open(struct inode *inode, struct file * file)
{
      int major = imajor(inode);
      struct snd_hwdep *hw;
      int err;
      wait_queue_t wait;

      if (major == snd_major) {
            hw = snd_lookup_minor_data(iminor(inode),
                                 SNDRV_DEVICE_TYPE_HWDEP);
#ifdef CONFIG_SND_OSSEMUL
      } else if (major == SOUND_MAJOR) {
            hw = snd_lookup_oss_minor_data(iminor(inode),
                                     SNDRV_OSS_DEVICE_TYPE_DMFM);
#endif
      } else
            return -ENXIO;
      if (hw == NULL)
            return -ENODEV;

      if (!hw->ops.open)
            return -ENXIO;

      if (!try_module_get(hw->card->module))
            return -EFAULT;

      init_waitqueue_entry(&wait, current);
      add_wait_queue(&hw->open_wait, &wait);
      mutex_lock(&hw->open_mutex);
      while (1) {
            if (hw->exclusive && hw->used > 0) {
                  err = -EBUSY;
                  break;
            }
            err = hw->ops.open(hw, file);
            if (err >= 0)
                  break;
            if (err == -EAGAIN) {
                  if (file->f_flags & O_NONBLOCK) {
                        err = -EBUSY;
                        break;
                  }
            } else
                  break;
            set_current_state(TASK_INTERRUPTIBLE);
            mutex_unlock(&hw->open_mutex);
            schedule();
            mutex_lock(&hw->open_mutex);
            if (signal_pending(current)) {
                  err = -ERESTARTSYS;
                  break;
            }
      }
      remove_wait_queue(&hw->open_wait, &wait);
      if (err >= 0) {
            err = snd_card_file_add(hw->card, file);
            if (err >= 0) {
                  file->private_data = hw;
                  hw->used++;
            } else {
                  if (hw->ops.release)
                        hw->ops.release(hw, file);
            }
      }
      mutex_unlock(&hw->open_mutex);
      if (err < 0)
            module_put(hw->card->module);
      return err;
}

static int snd_hwdep_release(struct inode *inode, struct file * file)
{
      int err = -ENXIO;
      struct snd_hwdep *hw = file->private_data;
      struct module *mod = hw->card->module;

      mutex_lock(&hw->open_mutex);
      if (hw->ops.release)
            err = hw->ops.release(hw, file);
      if (hw->used > 0)
            hw->used--;
      mutex_unlock(&hw->open_mutex);
      wake_up(&hw->open_wait);

      snd_card_file_remove(hw->card, file);
      module_put(mod);
      return err;
}

static unsigned int snd_hwdep_poll(struct file * file, poll_table * wait)
{
      struct snd_hwdep *hw = file->private_data;
      if (hw->ops.poll)
            return hw->ops.poll(hw, file, wait);
      return 0;
}

static int snd_hwdep_info(struct snd_hwdep *hw,
                    struct snd_hwdep_info __user *_info)
{
      struct snd_hwdep_info info;
      
      memset(&info, 0, sizeof(info));
      info.card = hw->card->number;
      strlcpy(info.id, hw->id, sizeof(info.id));      
      strlcpy(info.name, hw->name, sizeof(info.name));
      info.iface = hw->iface;
      if (copy_to_user(_info, &info, sizeof(info)))
            return -EFAULT;
      return 0;
}

static int snd_hwdep_dsp_status(struct snd_hwdep *hw,
                        struct snd_hwdep_dsp_status __user *_info)
{
      struct snd_hwdep_dsp_status info;
      int err;
      
      if (! hw->ops.dsp_status)
            return -ENXIO;
      memset(&info, 0, sizeof(info));
      info.dsp_loaded = hw->dsp_loaded;
      if ((err = hw->ops.dsp_status(hw, &info)) < 0)
            return err;
      if (copy_to_user(_info, &info, sizeof(info)))
            return -EFAULT;
      return 0;
}

static int snd_hwdep_dsp_load(struct snd_hwdep *hw,
                        struct snd_hwdep_dsp_image __user *_info)
{
      struct snd_hwdep_dsp_image info;
      int err;
      
      if (! hw->ops.dsp_load)
            return -ENXIO;
      memset(&info, 0, sizeof(info));
      if (copy_from_user(&info, _info, sizeof(info)))
            return -EFAULT;
      /* check whether the dsp was already loaded */
      if (hw->dsp_loaded & (1 << info.index))
            return -EBUSY;
      if (!access_ok(VERIFY_READ, info.image, info.length))
            return -EFAULT;
      err = hw->ops.dsp_load(hw, &info);
      if (err < 0)
            return err;
      hw->dsp_loaded |= (1 << info.index);
      return 0;
}

static long snd_hwdep_ioctl(struct file * file, unsigned int cmd,
                      unsigned long arg)
{
      struct snd_hwdep *hw = file->private_data;
      void __user *argp = (void __user *)arg;
      switch (cmd) {
      case SNDRV_HWDEP_IOCTL_PVERSION:
            return put_user(SNDRV_HWDEP_VERSION, (int __user *)argp);
      case SNDRV_HWDEP_IOCTL_INFO:
            return snd_hwdep_info(hw, argp);
      case SNDRV_HWDEP_IOCTL_DSP_STATUS:
            return snd_hwdep_dsp_status(hw, argp);
      case SNDRV_HWDEP_IOCTL_DSP_LOAD:
            return snd_hwdep_dsp_load(hw, argp);
      }
      if (hw->ops.ioctl)
            return hw->ops.ioctl(hw, file, cmd, arg);
      return -ENOTTY;
}

static int snd_hwdep_mmap(struct file * file, struct vm_area_struct * vma)
{
      struct snd_hwdep *hw = file->private_data;
      if (hw->ops.mmap)
            return hw->ops.mmap(hw, file, vma);
      return -ENXIO;
}

static int snd_hwdep_control_ioctl(struct snd_card *card,
                           struct snd_ctl_file * control,
                           unsigned int cmd, unsigned long arg)
{
      switch (cmd) {
      case SNDRV_CTL_IOCTL_HWDEP_NEXT_DEVICE:
            {
                  int device;

                  if (get_user(device, (int __user *)arg))
                        return -EFAULT;
                  mutex_lock(&register_mutex);
                  device = device < 0 ? 0 : device + 1;
                  while (device < SNDRV_MINOR_HWDEPS) {
                        if (snd_hwdep_search(card, device))
                              break;
                        device++;
                  }
                  if (device >= SNDRV_MINOR_HWDEPS)
                        device = -1;
                  mutex_unlock(&register_mutex);
                  if (put_user(device, (int __user *)arg))
                        return -EFAULT;
                  return 0;
            }
      case SNDRV_CTL_IOCTL_HWDEP_INFO:
            {
                  struct snd_hwdep_info __user *info = (struct snd_hwdep_info __user *)arg;
                  int device, err;
                  struct snd_hwdep *hwdep;

                  if (get_user(device, &info->device))
                        return -EFAULT;
                  mutex_lock(&register_mutex);
                  hwdep = snd_hwdep_search(card, device);
                  if (hwdep)
                        err = snd_hwdep_info(hwdep, info);
                  else
                        err = -ENXIO;
                  mutex_unlock(&register_mutex);
                  return err;
            }
      }
      return -ENOIOCTLCMD;
}

#ifdef CONFIG_COMPAT
#include "hwdep_compat.c"
#else
#define snd_hwdep_ioctl_compat      NULL
#endif

/*

 */

static const struct file_operations snd_hwdep_f_ops =
{
      .owner =    THIS_MODULE,
      .llseek =   snd_hwdep_llseek,
      .read =     snd_hwdep_read,
      .write =    snd_hwdep_write,
      .open =           snd_hwdep_open,
      .release =  snd_hwdep_release,
      .poll =           snd_hwdep_poll,
      .unlocked_ioctl = snd_hwdep_ioctl,
      .compat_ioctl =   snd_hwdep_ioctl_compat,
      .mmap =           snd_hwdep_mmap,
};

/**
 * snd_hwdep_new - create a new hwdep instance
 * @card: the card instance
 * @id: the id string
 * @device: the device index (zero-based)
 * @rhwdep: the pointer to store the new hwdep instance
 *
 * Creates a new hwdep instance with the given index on the card.
 * The callbacks (hwdep->ops) must be set on the returned instance
 * after this call manually by the caller.
 *
 * Returns zero if successful, or a negative error code on failure.
 */
int snd_hwdep_new(struct snd_card *card, char *id, int device,
              struct snd_hwdep **rhwdep)
{
      struct snd_hwdep *hwdep;
      int err;
      static struct snd_device_ops ops = {
            .dev_free = snd_hwdep_dev_free,
            .dev_register = snd_hwdep_dev_register,
            .dev_disconnect = snd_hwdep_dev_disconnect,
      };

      if (snd_BUG_ON(!card))
            return -ENXIO;
      if (rhwdep)
            *rhwdep = NULL;
      hwdep = kzalloc(sizeof(*hwdep), GFP_KERNEL);
      if (hwdep == NULL) {
            snd_printk(KERN_ERR "hwdep: cannot allocate\n");
            return -ENOMEM;
      }
      hwdep->card = card;
      hwdep->device = device;
      if (id)
            strlcpy(hwdep->id, id, sizeof(hwdep->id));
#ifdef CONFIG_SND_OSSEMUL
      hwdep->oss_type = -1;
#endif
      if ((err = snd_device_new(card, SNDRV_DEV_HWDEP, hwdep, &ops)) < 0) {
            snd_hwdep_free(hwdep);
            return err;
      }
      init_waitqueue_head(&hwdep->open_wait);
      mutex_init(&hwdep->open_mutex);
      if (rhwdep)
            *rhwdep = hwdep;
      return 0;
}

static int snd_hwdep_free(struct snd_hwdep *hwdep)
{
      if (!hwdep)
            return 0;
      if (hwdep->private_free)
            hwdep->private_free(hwdep);
      kfree(hwdep);
      return 0;
}

static int snd_hwdep_dev_free(struct snd_device *device)
{
      struct snd_hwdep *hwdep = device->device_data;
      return snd_hwdep_free(hwdep);
}

static int snd_hwdep_dev_register(struct snd_device *device)
{
      struct snd_hwdep *hwdep = device->device_data;
      int err;
      char name[32];

      mutex_lock(&register_mutex);
      if (snd_hwdep_search(hwdep->card, hwdep->device)) {
            mutex_unlock(&register_mutex);
            return -EBUSY;
      }
      list_add_tail(&hwdep->list, &snd_hwdep_devices);
      sprintf(name, "hwC%iD%i", hwdep->card->number, hwdep->device);
      if ((err = snd_register_device(SNDRV_DEVICE_TYPE_HWDEP,
                               hwdep->card, hwdep->device,
                               &snd_hwdep_f_ops, hwdep, name)) < 0) {
            snd_printk(KERN_ERR "unable to register hardware dependent device %i:%i\n",
                     hwdep->card->number, hwdep->device);
            list_del(&hwdep->list);
            mutex_unlock(&register_mutex);
            return err;
      }
#ifdef CONFIG_SND_OSSEMUL
      hwdep->ossreg = 0;
      if (hwdep->oss_type >= 0) {
            if ((hwdep->oss_type == SNDRV_OSS_DEVICE_TYPE_DMFM) && (hwdep->device != 0)) {
                  snd_printk (KERN_WARNING "only hwdep device 0 can be registered as OSS direct FM device!\n");
            } else {
                  if (snd_register_oss_device(hwdep->oss_type,
                                        hwdep->card, hwdep->device,
                                        &snd_hwdep_f_ops, hwdep,
                                        hwdep->oss_dev) < 0) {
                        snd_printk(KERN_ERR "unable to register OSS compatibility device %i:%i\n",
                                 hwdep->card->number, hwdep->device);
                  } else
                        hwdep->ossreg = 1;
            }
      }
#endif
      mutex_unlock(&register_mutex);
      return 0;
}

static int snd_hwdep_dev_disconnect(struct snd_device *device)
{
      struct snd_hwdep *hwdep = device->device_data;

      if (snd_BUG_ON(!hwdep))
            return -ENXIO;
      mutex_lock(&register_mutex);
      if (snd_hwdep_search(hwdep->card, hwdep->device) != hwdep) {
            mutex_unlock(&register_mutex);
            return -EINVAL;
      }
#ifdef CONFIG_SND_OSSEMUL
      if (hwdep->ossreg)
            snd_unregister_oss_device(hwdep->oss_type, hwdep->card, hwdep->device);
#endif
      snd_unregister_device(SNDRV_DEVICE_TYPE_HWDEP, hwdep->card, hwdep->device);
      list_del_init(&hwdep->list);
      mutex_unlock(&register_mutex);
      return 0;
}

#ifdef CONFIG_PROC_FS
/*
 *  Info interface
 */

static void snd_hwdep_proc_read(struct snd_info_entry *entry,
                        struct snd_info_buffer *buffer)
{
      struct snd_hwdep *hwdep;

      mutex_lock(&register_mutex);
      list_for_each_entry(hwdep, &snd_hwdep_devices, list)
            snd_iprintf(buffer, "%02i-%02i: %s\n",
                      hwdep->card->number, hwdep->device, hwdep->name);
      mutex_unlock(&register_mutex);
}

static struct snd_info_entry *snd_hwdep_proc_entry;

static void __init snd_hwdep_proc_init(void)
{
      struct snd_info_entry *entry;

      if ((entry = snd_info_create_module_entry(THIS_MODULE, "hwdep", NULL)) != NULL) {
            entry->c.text.read = snd_hwdep_proc_read;
            if (snd_info_register(entry) < 0) {
                  snd_info_free_entry(entry);
                  entry = NULL;
            }
      }
      snd_hwdep_proc_entry = entry;
}

static void __exit snd_hwdep_proc_done(void)
{
      snd_info_free_entry(snd_hwdep_proc_entry);
}
#else /* !CONFIG_PROC_FS */
#define snd_hwdep_proc_init()
#define snd_hwdep_proc_done()
#endif /* CONFIG_PROC_FS */


/*
 *  ENTRY functions
 */

static int __init alsa_hwdep_init(void)
{
      snd_hwdep_proc_init();
      snd_ctl_register_ioctl(snd_hwdep_control_ioctl);
      snd_ctl_register_ioctl_compat(snd_hwdep_control_ioctl);
      return 0;
}

static void __exit alsa_hwdep_exit(void)
{
      snd_ctl_unregister_ioctl(snd_hwdep_control_ioctl);
      snd_ctl_unregister_ioctl_compat(snd_hwdep_control_ioctl);
      snd_hwdep_proc_done();
}

module_init(alsa_hwdep_init)
module_exit(alsa_hwdep_exit)

EXPORT_SYMBOL(snd_hwdep_new);

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