]> nv-tegra.nvidia Code Review - linux-2.6.git/blobdiff - sound/core/sound.c
[ALSA] dynamic minors (4/6): dynamic minor number allocation
[linux-2.6.git] / sound / core / sound.c
index b57519a3e3d90058135dc2781cbf72e14a36acd9..5e22283078fc38fb64a59df64df6b9d822772fff 100644 (file)
@@ -32,7 +32,6 @@
 #include <sound/initval.h>
 #include <linux/kmod.h>
 #include <linux/devfs_fs_kernel.h>
-#include <linux/device.h>
 
 #define SNDRV_OS_MINORS 256
 
@@ -60,8 +59,7 @@ MODULE_ALIAS_CHARDEV_MAJOR(CONFIG_SND_MAJOR);
  */
 int snd_ecards_limit;
 
-static struct list_head snd_minors_hash[SNDRV_CARDS];
-
+static struct snd_minor *snd_minors[SNDRV_OS_MINORS];
 static DECLARE_MUTEX(sound_mutex);
 
 extern struct class *sound_class;
@@ -108,44 +106,61 @@ static void snd_request_other(int minor)
 
 #endif                         /* request_module support */
 
-static snd_minor_t *snd_minor_search(int minor)
+/**
+ * snd_lookup_minor_data - get user data of a registered device
+ * @minor: the minor number
+ * @type: device type (SNDRV_DEVICE_TYPE_XXX)
+ *
+ * Checks that a minor device with the specified type is registered, and returns
+ * its user data pointer.
+ */
+void *snd_lookup_minor_data(unsigned int minor, int type)
 {
-       struct list_head *list;
-       snd_minor_t *mptr;
+       struct snd_minor *mreg;
+       void *private_data;
 
-       list_for_each(list, &snd_minors_hash[SNDRV_MINOR_CARD(minor)]) {
-               mptr = list_entry(list, snd_minor_t, list);
-               if (mptr->number == minor)
-                       return mptr;
-       }
-       return NULL;
+       if (minor > ARRAY_SIZE(snd_minors))
+               return NULL;
+       down(&sound_mutex);
+       mreg = snd_minors[minor];
+       if (mreg && mreg->type == type)
+               private_data = mreg->private_data;
+       else
+               private_data = NULL;
+       up(&sound_mutex);
+       return private_data;
 }
 
 static int snd_open(struct inode *inode, struct file *file)
 {
-       int minor = iminor(inode);
-       int card = SNDRV_MINOR_CARD(minor);
-       int dev = SNDRV_MINOR_DEVICE(minor);
-       snd_minor_t *mptr = NULL;
+       unsigned int minor = iminor(inode);
+       struct snd_minor *mptr = NULL;
        struct file_operations *old_fops;
        int err = 0;
 
-       if (dev != SNDRV_MINOR_SEQUENCER && dev != SNDRV_MINOR_TIMER) {
-               if (snd_cards[card] == NULL) {
+       if (minor > ARRAY_SIZE(snd_minors))
+               return -ENODEV;
+       mptr = snd_minors[minor];
+       if (mptr == NULL) {
 #ifdef CONFIG_KMOD
-                       snd_request_card(card);
+               int dev = SNDRV_MINOR_DEVICE(minor);
+               if (dev == SNDRV_MINOR_CONTROL) {
+                       /* /dev/aloadC? */
+                       int card = SNDRV_MINOR_CARD(minor);
                        if (snd_cards[card] == NULL)
-#endif
-                               return -ENODEV;
-               }
-       } else {
-#ifdef CONFIG_KMOD
-               if ((mptr = snd_minor_search(minor)) == NULL)
+                               snd_request_card(card);
+               } else if (dev == SNDRV_MINOR_GLOBAL) {
+                       /* /dev/aloadSEQ */
                        snd_request_other(minor);
+               }
+#ifndef CONFIG_SND_DYNAMIC_MINORS
+               /* /dev/snd/{controlC?,seq} */
+               mptr = snd_minors[minor];
+               if (mptr == NULL)
+#endif
 #endif
+                       return -ENODEV;
        }
-       if (mptr == NULL && (mptr = snd_minor_search(minor)) == NULL)
-               return -ENODEV;
        old_fops = file->f_op;
        file->f_op = fops_get(mptr->f_ops);
        if (file->f_op->open)
@@ -164,7 +179,23 @@ static struct file_operations snd_fops =
        .open =         snd_open
 };
 
-static int snd_kernel_minor(int type, snd_card_t * card, int dev)
+#ifdef CONFIG_SND_DYNAMIC_MINORS
+static int snd_find_free_minor(void)
+{
+       int minor;
+
+       for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor) {
+               /* skip minors still used statically for autoloading devices */
+               if (SNDRV_MINOR_DEVICE(minor) == SNDRV_MINOR_CONTROL ||
+                   minor == SNDRV_MINOR_SEQUENCER)
+                       continue;
+               if (!snd_minors[minor])
+                       return minor;
+       }
+       return -EBUSY;
+}
+#else
+static int snd_kernel_minor(int type, struct snd_card *card, int dev)
 {
        int minor;
 
@@ -190,13 +221,15 @@ static int snd_kernel_minor(int type, snd_card_t * card, int dev)
        snd_assert(minor >= 0 && minor < SNDRV_OS_MINORS, return -EINVAL);
        return minor;
 }
+#endif
 
 /**
  * snd_register_device - Register the ALSA device file for the card
  * @type: the device type, SNDRV_DEVICE_TYPE_XXX
  * @card: the card instance
  * @dev: the device index
- * @reg: the snd_minor_t record
+ * @f_ops: the file operations
+ * @private_data: user pointer for f_ops->open()
  * @name: the device file name
  *
  * Registers an ALSA device file for the given card.
@@ -204,30 +237,39 @@ static int snd_kernel_minor(int type, snd_card_t * card, int dev)
  *
  * Retrurns zero if successful, or a negative error code on failure.
  */
-int snd_register_device(int type, snd_card_t * card, int dev, snd_minor_t * reg, const char *name)
+int snd_register_device(int type, struct snd_card *card, int dev,
+                       struct file_operations *f_ops, void *private_data,
+                       const char *name)
 {
-       int minor = snd_kernel_minor(type, card, dev);
-       snd_minor_t *preg;
+       int minor;
+       struct snd_minor *preg;
        struct device *device = NULL;
 
-       if (minor < 0)
-               return minor;
        snd_assert(name, return -EINVAL);
-       preg = (snd_minor_t *)kmalloc(sizeof(snd_minor_t) + strlen(name) + 1, GFP_KERNEL);
+       preg = kmalloc(sizeof(struct snd_minor) + strlen(name) + 1, GFP_KERNEL);
        if (preg == NULL)
                return -ENOMEM;
-       *preg = *reg;
-       preg->number = minor;
+       preg->type = type;
+       preg->card = card ? card->number : -1;
        preg->device = dev;
+       preg->f_ops = f_ops;
+       preg->private_data = private_data;
        strcpy(preg->name, name);
        down(&sound_mutex);
-       if (snd_minor_search(minor)) {
+#ifdef CONFIG_SND_DYNAMIC_MINORS
+       minor = snd_find_free_minor();
+#else
+       minor = snd_kernel_minor(type, card, dev);
+       if (minor >= 0 && snd_minors[minor])
+               minor = -EBUSY;
+#endif
+       if (minor < 0) {
                up(&sound_mutex);
                kfree(preg);
-               return -EBUSY;
+               return minor;
        }
-       list_add_tail(&preg->list, &snd_minors_hash[SNDRV_MINOR_CARD(minor)]);
-       if (strncmp(name, "controlC", 8) || card->number >= cards_limit)
+       snd_minors[minor] = preg;
+       if (type != SNDRV_DEVICE_TYPE_CONTROL || preg->card >= cards_limit)
                devfs_mk_cdev(MKDEV(major, minor), S_IFCHR | device_mode, "snd/%s", name);
        if (card)
                device = card->dev;
@@ -248,24 +290,30 @@ int snd_register_device(int type, snd_card_t * card, int dev, snd_minor_t * reg,
  *
  * Returns zero if sucecessful, or a negative error code on failure
  */
-int snd_unregister_device(int type, snd_card_t * card, int dev)
+int snd_unregister_device(int type, struct snd_card *card, int dev)
 {
-       int minor = snd_kernel_minor(type, card, dev);
-       snd_minor_t *mptr;
+       int cardnum, minor;
+       struct snd_minor *mptr;
 
-       if (minor < 0)
-               return minor;
+       cardnum = card ? card->number : -1;
        down(&sound_mutex);
-       if ((mptr = snd_minor_search(minor)) == NULL) {
+       for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor)
+               if ((mptr = snd_minors[minor]) != NULL &&
+                   mptr->type == type &&
+                   mptr->card == cardnum &&
+                   mptr->device == dev)
+                       break;
+       if (minor == ARRAY_SIZE(snd_minors)) {
                up(&sound_mutex);
                return -EINVAL;
        }
 
-       if (strncmp(mptr->name, "controlC", 8) || card->number >= cards_limit) /* created in sound.c */
+       if (mptr->type != SNDRV_DEVICE_TYPE_CONTROL ||
+           mptr->card >= cards_limit)                  /* created in sound.c */
                devfs_remove("snd/%s", mptr->name);
        class_device_destroy(sound_class, MKDEV(major, minor));
 
-       list_del(&mptr->list);
+       snd_minors[minor] = NULL;
        up(&sound_mutex);
        kfree(mptr);
        return 0;
@@ -275,34 +323,58 @@ int snd_unregister_device(int type, snd_card_t * card, int dev)
  *  INFO PART
  */
 
-static snd_info_entry_t *snd_minor_info_entry = NULL;
+static struct snd_info_entry *snd_minor_info_entry = NULL;
 
-static void snd_minor_info_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer)
+static const char *snd_device_type_name(int type)
 {
-       int card, device;
-       struct list_head *list;
-       snd_minor_t *mptr;
+       switch (type) {
+       case SNDRV_DEVICE_TYPE_CONTROL:
+               return "control";
+       case SNDRV_DEVICE_TYPE_HWDEP:
+               return "hardware dependent";
+       case SNDRV_DEVICE_TYPE_RAWMIDI:
+               return "raw midi";
+       case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
+               return "digital audio playback";
+       case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
+               return "digital audio capture";
+       case SNDRV_DEVICE_TYPE_SEQUENCER:
+               return "sequencer";
+       case SNDRV_DEVICE_TYPE_TIMER:
+               return "timer";
+       default:
+               return "?";
+       }
+}
+
+static void snd_minor_info_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
+{
+       int minor;
+       struct snd_minor *mptr;
 
        down(&sound_mutex);
-       for (card = 0; card < SNDRV_CARDS; card++) {
-               list_for_each(list, &snd_minors_hash[card]) {
-                       mptr = list_entry(list, snd_minor_t, list);
-                       if (SNDRV_MINOR_DEVICE(mptr->number) != SNDRV_MINOR_SEQUENCER) {
-                               if ((device = mptr->device) >= 0)
-                                       snd_iprintf(buffer, "%3i: [%i-%2i]: %s\n", mptr->number, card, device, mptr->comment);
-                               else
-                                       snd_iprintf(buffer, "%3i: [%i]   : %s\n", mptr->number, card, mptr->comment);
-                       } else {
-                               snd_iprintf(buffer, "%3i:       : %s\n", mptr->number, mptr->comment);
-                       }
-               }
+       for (minor = 0; minor < SNDRV_OS_MINORS; ++minor) {
+               if (!(mptr = snd_minors[minor]))
+                       continue;
+               if (mptr->card >= 0) {
+                       if (mptr->device >= 0)
+                               snd_iprintf(buffer, "%3i: [%i-%2i]: %s\n",
+                                           minor, mptr->card, mptr->device,
+                                           snd_device_type_name(mptr->type));
+                       else
+                               snd_iprintf(buffer, "%3i: [%i]   : %s\n",
+                                           minor, mptr->card,
+                                           snd_device_type_name(mptr->type));
+               } else
+                       snd_iprintf(buffer, "%3i:       : %s\n", minor,
+                                   snd_device_type_name(mptr->type));
        }
        up(&sound_mutex);
 }
 
 int __init snd_minor_info_init(void)
 {
-       snd_info_entry_t *entry;
+       struct snd_info_entry *entry;
 
        entry = snd_info_create_module_entry(THIS_MODULE, "devices", NULL);
        if (entry) {
@@ -328,39 +400,24 @@ int __exit snd_minor_info_done(void)
  *  INIT PART
  */
 
-#ifdef CONFIG_SND_GENERIC_DRIVER
-extern struct device_driver snd_generic_driver;
-#endif
-
 static int __init alsa_sound_init(void)
 {
        short controlnum;
-       int err;
-       int card;
 
        snd_major = major;
        snd_ecards_limit = cards_limit;
-       for (card = 0; card < SNDRV_CARDS; card++)
-               INIT_LIST_HEAD(&snd_minors_hash[card]);
-       if ((err = snd_oss_init_module()) < 0)
-               return err;
        devfs_mk_dir("snd");
        if (register_chrdev(major, "alsa", &snd_fops)) {
                snd_printk(KERN_ERR "unable to register native major device number %d\n", major);
                devfs_remove("snd");
                return -EIO;
        }
-       snd_memory_init();
        if (snd_info_init() < 0) {
-               snd_memory_done();
                unregister_chrdev(major, "alsa");
                devfs_remove("snd");
                return -ENOMEM;
        }
        snd_info_minor_register();
-#ifdef CONFIG_SND_GENERIC_DRIVER
-       driver_register(&snd_generic_driver);
-#endif
        for (controlnum = 0; controlnum < cards_limit; controlnum++)
                devfs_mk_cdev(MKDEV(major, controlnum<<5), S_IFCHR | device_mode, "snd/controlC%d", controlnum);
 #ifndef MODULE
@@ -376,12 +433,8 @@ static void __exit alsa_sound_exit(void)
        for (controlnum = 0; controlnum < cards_limit; controlnum++)
                devfs_remove("snd/controlC%d", controlnum);
 
-#ifdef CONFIG_SND_GENERIC_DRIVER
-       driver_unregister(&snd_generic_driver);
-#endif
        snd_info_minor_unregister();
        snd_info_done();
-       snd_memory_done();
        if (unregister_chrdev(major, "alsa") != 0)
                snd_printk(KERN_ERR "unable to unregister major device number %d\n", major);
        devfs_remove("snd");
@@ -398,19 +451,13 @@ EXPORT_SYMBOL(snd_request_card);
 #endif
 EXPORT_SYMBOL(snd_register_device);
 EXPORT_SYMBOL(snd_unregister_device);
+EXPORT_SYMBOL(snd_lookup_minor_data);
 #if defined(CONFIG_SND_OSSEMUL)
 EXPORT_SYMBOL(snd_register_oss_device);
 EXPORT_SYMBOL(snd_unregister_oss_device);
+EXPORT_SYMBOL(snd_lookup_oss_minor_data);
 #endif
   /* memory.c */
-#ifdef CONFIG_SND_DEBUG_MEMORY
-EXPORT_SYMBOL(snd_hidden_kmalloc);
-EXPORT_SYMBOL(snd_hidden_kcalloc);
-EXPORT_SYMBOL(snd_hidden_kfree);
-EXPORT_SYMBOL(snd_hidden_vmalloc);
-EXPORT_SYMBOL(snd_hidden_vfree);
-EXPORT_SYMBOL(snd_hidden_kstrdup);
-#endif
 EXPORT_SYMBOL(copy_to_user_fromio);
 EXPORT_SYMBOL(copy_from_user_toio);
   /* init.c */
@@ -426,19 +473,8 @@ EXPORT_SYMBOL(snd_card_register);
 EXPORT_SYMBOL(snd_component_add);
 EXPORT_SYMBOL(snd_card_file_add);
 EXPORT_SYMBOL(snd_card_file_remove);
-#ifdef CONFIG_SND_GENERIC_DRIVER
-EXPORT_SYMBOL(snd_card_set_generic_dev);
-#endif
 #ifdef CONFIG_PM
 EXPORT_SYMBOL(snd_power_wait);
-EXPORT_SYMBOL(snd_card_set_pm_callback);
-#ifdef CONFIG_SND_GENERIC_DRIVER
-EXPORT_SYMBOL(snd_card_set_generic_pm_callback);
-#endif
-#ifdef CONFIG_PCI
-EXPORT_SYMBOL(snd_card_pci_suspend);
-EXPORT_SYMBOL(snd_card_pci_resume);
-#endif
 #endif
   /* device.c */
 EXPORT_SYMBOL(snd_device_new);
@@ -487,17 +523,10 @@ EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat);
 EXPORT_SYMBOL(snd_ctl_elem_read);
 EXPORT_SYMBOL(snd_ctl_elem_write);
   /* misc.c */
-EXPORT_SYMBOL(snd_task_name);
+EXPORT_SYMBOL(release_and_free_resource);
 #ifdef CONFIG_SND_VERBOSE_PRINTK
 EXPORT_SYMBOL(snd_verbose_printk);
 #endif
 #if defined(CONFIG_SND_DEBUG) && defined(CONFIG_SND_VERBOSE_PRINTK)
 EXPORT_SYMBOL(snd_verbose_printd);
-#endif
-  /* wrappers */
-#ifdef CONFIG_SND_DEBUG_MEMORY
-EXPORT_SYMBOL(snd_wrapper_kmalloc);
-EXPORT_SYMBOL(snd_wrapper_kfree);
-EXPORT_SYMBOL(snd_wrapper_vmalloc);
-EXPORT_SYMBOL(snd_wrapper_vfree);
 #endif