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-rw-r--r--sound/core/info.c989
1 files changed, 989 insertions, 0 deletions
diff --git a/sound/core/info.c b/sound/core/info.c
new file mode 100644
index 00000000000..31faffe01cb
--- /dev/null
+++ b/sound/core/info.c
@@ -0,0 +1,989 @@
+/*
+ * Information interface for ALSA driver
+ * Copyright (c) by Jaroslav Kysela <perex@suse.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 <sound/driver.h>
+#include <linux/init.h>
+#include <linux/vmalloc.h>
+#include <linux/time.h>
+#include <linux/smp_lock.h>
+#include <sound/core.h>
+#include <sound/minors.h>
+#include <sound/info.h>
+#include <sound/version.h>
+#include <linux/proc_fs.h>
+#include <linux/devfs_fs_kernel.h>
+#include <stdarg.h>
+
+/*
+ *
+ */
+
+int snd_info_check_reserved_words(const char *str)
+{
+ static char *reserved[] =
+ {
+ "version",
+ "meminfo",
+ "memdebug",
+ "detect",
+ "devices",
+ "oss",
+ "cards",
+ "timers",
+ "synth",
+ "pcm",
+ "seq",
+ NULL
+ };
+ char **xstr = reserved;
+
+ while (*xstr) {
+ if (!strcmp(*xstr, str))
+ return 0;
+ xstr++;
+ }
+ if (!strncmp(str, "card", 4))
+ return 0;
+ return 1;
+}
+
+#ifdef CONFIG_PROC_FS
+
+static DECLARE_MUTEX(info_mutex);
+
+typedef struct _snd_info_private_data {
+ snd_info_buffer_t *rbuffer;
+ snd_info_buffer_t *wbuffer;
+ snd_info_entry_t *entry;
+ void *file_private_data;
+} snd_info_private_data_t;
+
+static int snd_info_version_init(void);
+static int snd_info_version_done(void);
+
+
+/**
+ * snd_iprintf - printf on the procfs buffer
+ * @buffer: the procfs buffer
+ * @fmt: the printf format
+ *
+ * Outputs the string on the procfs buffer just like printf().
+ *
+ * Returns the size of output string.
+ */
+int snd_iprintf(snd_info_buffer_t * buffer, char *fmt,...)
+{
+ va_list args;
+ int len, res;
+
+ if (buffer->stop || buffer->error)
+ return 0;
+ len = buffer->len - buffer->size;
+ va_start(args, fmt);
+ res = vsnprintf(buffer->curr, len, fmt, args);
+ va_end(args);
+ if (res >= len) {
+ buffer->stop = 1;
+ return 0;
+ }
+ buffer->curr += res;
+ buffer->size += res;
+ return res;
+}
+
+/*
+
+ */
+
+static struct proc_dir_entry *snd_proc_root = NULL;
+snd_info_entry_t *snd_seq_root = NULL;
+#ifdef CONFIG_SND_OSSEMUL
+snd_info_entry_t *snd_oss_root = NULL;
+#endif
+
+static inline void snd_info_entry_prepare(struct proc_dir_entry *de)
+{
+ de->owner = THIS_MODULE;
+}
+
+static void snd_remove_proc_entry(struct proc_dir_entry *parent,
+ struct proc_dir_entry *de)
+{
+ if (de)
+ remove_proc_entry(de->name, parent);
+}
+
+static loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig)
+{
+ snd_info_private_data_t *data;
+ struct snd_info_entry *entry;
+ loff_t ret;
+
+ data = file->private_data;
+ entry = data->entry;
+ lock_kernel();
+ switch (entry->content) {
+ case SNDRV_INFO_CONTENT_TEXT:
+ switch (orig) {
+ case 0: /* SEEK_SET */
+ file->f_pos = offset;
+ ret = file->f_pos;
+ goto out;
+ case 1: /* SEEK_CUR */
+ file->f_pos += offset;
+ ret = file->f_pos;
+ goto out;
+ case 2: /* SEEK_END */
+ default:
+ ret = -EINVAL;
+ goto out;
+ }
+ break;
+ case SNDRV_INFO_CONTENT_DATA:
+ if (entry->c.ops->llseek) {
+ ret = entry->c.ops->llseek(entry,
+ data->file_private_data,
+ file, offset, orig);
+ goto out;
+ }
+ break;
+ }
+ ret = -ENXIO;
+out:
+ unlock_kernel();
+ return ret;
+}
+
+static ssize_t snd_info_entry_read(struct file *file, char __user *buffer,
+ size_t count, loff_t * offset)
+{
+ snd_info_private_data_t *data;
+ struct snd_info_entry *entry;
+ snd_info_buffer_t *buf;
+ size_t size = 0;
+ loff_t pos;
+
+ data = file->private_data;
+ snd_assert(data != NULL, return -ENXIO);
+ pos = *offset;
+ if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
+ return -EIO;
+ if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
+ return -EIO;
+ entry = data->entry;
+ switch (entry->content) {
+ case SNDRV_INFO_CONTENT_TEXT:
+ buf = data->rbuffer;
+ if (buf == NULL)
+ return -EIO;
+ if (pos >= buf->size)
+ return 0;
+ size = buf->size - pos;
+ size = min(count, size);
+ if (copy_to_user(buffer, buf->buffer + pos, size))
+ return -EFAULT;
+ break;
+ case SNDRV_INFO_CONTENT_DATA:
+ if (entry->c.ops->read)
+ size = entry->c.ops->read(entry,
+ data->file_private_data,
+ file, buffer, count, pos);
+ break;
+ }
+ if ((ssize_t) size > 0)
+ *offset = pos + size;
+ return size;
+}
+
+static ssize_t snd_info_entry_write(struct file *file, const char __user *buffer,
+ size_t count, loff_t * offset)
+{
+ snd_info_private_data_t *data;
+ struct snd_info_entry *entry;
+ snd_info_buffer_t *buf;
+ size_t size = 0;
+ loff_t pos;
+
+ data = file->private_data;
+ snd_assert(data != NULL, return -ENXIO);
+ entry = data->entry;
+ pos = *offset;
+ if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
+ return -EIO;
+ if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
+ return -EIO;
+ switch (entry->content) {
+ case SNDRV_INFO_CONTENT_TEXT:
+ buf = data->wbuffer;
+ if (buf == NULL)
+ return -EIO;
+ if (pos >= buf->len)
+ return -ENOMEM;
+ size = buf->len - pos;
+ size = min(count, size);
+ if (copy_from_user(buf->buffer + pos, buffer, size))
+ return -EFAULT;
+ if ((long)buf->size < pos + size)
+ buf->size = pos + size;
+ break;
+ case SNDRV_INFO_CONTENT_DATA:
+ if (entry->c.ops->write)
+ size = entry->c.ops->write(entry,
+ data->file_private_data,
+ file, buffer, count, pos);
+ break;
+ }
+ if ((ssize_t) size > 0)
+ *offset = pos + size;
+ return size;
+}
+
+static int snd_info_entry_open(struct inode *inode, struct file *file)
+{
+ snd_info_entry_t *entry;
+ snd_info_private_data_t *data;
+ snd_info_buffer_t *buffer;
+ struct proc_dir_entry *p;
+ int mode, err;
+
+ down(&info_mutex);
+ p = PDE(inode);
+ entry = p == NULL ? NULL : (snd_info_entry_t *)p->data;
+ if (entry == NULL || entry->disconnected) {
+ up(&info_mutex);
+ return -ENODEV;
+ }
+ if (!try_module_get(entry->module)) {
+ err = -EFAULT;
+ goto __error1;
+ }
+ mode = file->f_flags & O_ACCMODE;
+ if (mode == O_RDONLY || mode == O_RDWR) {
+ if ((entry->content == SNDRV_INFO_CONTENT_TEXT &&
+ !entry->c.text.read_size) ||
+ (entry->content == SNDRV_INFO_CONTENT_DATA &&
+ entry->c.ops->read == NULL)) {
+ err = -ENODEV;
+ goto __error;
+ }
+ }
+ if (mode == O_WRONLY || mode == O_RDWR) {
+ if ((entry->content == SNDRV_INFO_CONTENT_TEXT &&
+ !entry->c.text.write_size) ||
+ (entry->content == SNDRV_INFO_CONTENT_DATA &&
+ entry->c.ops->write == NULL)) {
+ err = -ENODEV;
+ goto __error;
+ }
+ }
+ data = kcalloc(1, sizeof(*data), GFP_KERNEL);
+ if (data == NULL) {
+ err = -ENOMEM;
+ goto __error;
+ }
+ data->entry = entry;
+ switch (entry->content) {
+ case SNDRV_INFO_CONTENT_TEXT:
+ if (mode == O_RDONLY || mode == O_RDWR) {
+ buffer = kcalloc(1, sizeof(*buffer), GFP_KERNEL);
+ if (buffer == NULL) {
+ kfree(data);
+ err = -ENOMEM;
+ goto __error;
+ }
+ buffer->len = (entry->c.text.read_size +
+ (PAGE_SIZE - 1)) & ~(PAGE_SIZE - 1);
+ buffer->buffer = vmalloc(buffer->len);
+ if (buffer->buffer == NULL) {
+ kfree(buffer);
+ kfree(data);
+ err = -ENOMEM;
+ goto __error;
+ }
+ buffer->curr = buffer->buffer;
+ data->rbuffer = buffer;
+ }
+ if (mode == O_WRONLY || mode == O_RDWR) {
+ buffer = kcalloc(1, sizeof(*buffer), GFP_KERNEL);
+ if (buffer == NULL) {
+ if (mode == O_RDWR) {
+ vfree(data->rbuffer->buffer);
+ kfree(data->rbuffer);
+ }
+ kfree(data);
+ err = -ENOMEM;
+ goto __error;
+ }
+ buffer->len = (entry->c.text.write_size +
+ (PAGE_SIZE - 1)) & ~(PAGE_SIZE - 1);
+ buffer->buffer = vmalloc(buffer->len);
+ if (buffer->buffer == NULL) {
+ if (mode == O_RDWR) {
+ vfree(data->rbuffer->buffer);
+ kfree(data->rbuffer);
+ }
+ kfree(buffer);
+ kfree(data);
+ err = -ENOMEM;
+ goto __error;
+ }
+ buffer->curr = buffer->buffer;
+ data->wbuffer = buffer;
+ }
+ break;
+ case SNDRV_INFO_CONTENT_DATA: /* data */
+ if (entry->c.ops->open) {
+ if ((err = entry->c.ops->open(entry, mode,
+ &data->file_private_data)) < 0) {
+ kfree(data);
+ goto __error;
+ }
+ }
+ break;
+ }
+ file->private_data = data;
+ up(&info_mutex);
+ if (entry->content == SNDRV_INFO_CONTENT_TEXT &&
+ (mode == O_RDONLY || mode == O_RDWR)) {
+ if (entry->c.text.read) {
+ down(&entry->access);
+ entry->c.text.read(entry, data->rbuffer);
+ up(&entry->access);
+ }
+ }
+ return 0;
+
+ __error:
+ module_put(entry->module);
+ __error1:
+ up(&info_mutex);
+ return err;
+}
+
+static int snd_info_entry_release(struct inode *inode, struct file *file)
+{
+ snd_info_entry_t *entry;
+ snd_info_private_data_t *data;
+ int mode;
+
+ mode = file->f_flags & O_ACCMODE;
+ data = file->private_data;
+ entry = data->entry;
+ switch (entry->content) {
+ case SNDRV_INFO_CONTENT_TEXT:
+ if (mode == O_RDONLY || mode == O_RDWR) {
+ vfree(data->rbuffer->buffer);
+ kfree(data->rbuffer);
+ }
+ if (mode == O_WRONLY || mode == O_RDWR) {
+ if (entry->c.text.write) {
+ entry->c.text.write(entry, data->wbuffer);
+ if (data->wbuffer->error) {
+ snd_printk(KERN_WARNING "data write error to %s (%i)\n",
+ entry->name,
+ data->wbuffer->error);
+ }
+ }
+ vfree(data->wbuffer->buffer);
+ kfree(data->wbuffer);
+ }
+ break;
+ case SNDRV_INFO_CONTENT_DATA:
+ if (entry->c.ops->release)
+ entry->c.ops->release(entry, mode,
+ data->file_private_data);
+ break;
+ }
+ module_put(entry->module);
+ kfree(data);
+ return 0;
+}
+
+static unsigned int snd_info_entry_poll(struct file *file, poll_table * wait)
+{
+ snd_info_private_data_t *data;
+ struct snd_info_entry *entry;
+ unsigned int mask;
+
+ data = file->private_data;
+ if (data == NULL)
+ return 0;
+ entry = data->entry;
+ mask = 0;
+ switch (entry->content) {
+ case SNDRV_INFO_CONTENT_DATA:
+ if (entry->c.ops->poll)
+ return entry->c.ops->poll(entry,
+ data->file_private_data,
+ file, wait);
+ if (entry->c.ops->read)
+ mask |= POLLIN | POLLRDNORM;
+ if (entry->c.ops->write)
+ mask |= POLLOUT | POLLWRNORM;
+ break;
+ }
+ return mask;
+}
+
+static inline int _snd_info_entry_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ snd_info_private_data_t *data;
+ struct snd_info_entry *entry;
+
+ data = file->private_data;
+ if (data == NULL)
+ return 0;
+ entry = data->entry;
+ switch (entry->content) {
+ case SNDRV_INFO_CONTENT_DATA:
+ if (entry->c.ops->ioctl)
+ return entry->c.ops->ioctl(entry,
+ data->file_private_data,
+ file, cmd, arg);
+ break;
+ }
+ return -ENOTTY;
+}
+
+/* FIXME: need to unlock BKL to allow preemption */
+static int snd_info_entry_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ int err;
+ unlock_kernel();
+ err = _snd_info_entry_ioctl(inode, file, cmd, arg);
+ lock_kernel();
+ return err;
+}
+
+static int snd_info_entry_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct inode *inode = file->f_dentry->d_inode;
+ snd_info_private_data_t *data;
+ struct snd_info_entry *entry;
+
+ data = file->private_data;
+ if (data == NULL)
+ return 0;
+ entry = data->entry;
+ switch (entry->content) {
+ case SNDRV_INFO_CONTENT_DATA:
+ if (entry->c.ops->mmap)
+ return entry->c.ops->mmap(entry,
+ data->file_private_data,
+ inode, file, vma);
+ break;
+ }
+ return -ENXIO;
+}
+
+static struct file_operations snd_info_entry_operations =
+{
+ .owner = THIS_MODULE,
+ .llseek = snd_info_entry_llseek,
+ .read = snd_info_entry_read,
+ .write = snd_info_entry_write,
+ .poll = snd_info_entry_poll,
+ .ioctl = snd_info_entry_ioctl,
+ .mmap = snd_info_entry_mmap,
+ .open = snd_info_entry_open,
+ .release = snd_info_entry_release,
+};
+
+/**
+ * snd_create_proc_entry - create a procfs entry
+ * @name: the name of the proc file
+ * @mode: the file permission bits, S_Ixxx
+ * @parent: the parent proc-directory entry
+ *
+ * Creates a new proc file entry with the given name and permission
+ * on the given directory.
+ *
+ * Returns the pointer of new instance or NULL on failure.
+ */
+static struct proc_dir_entry *snd_create_proc_entry(const char *name, mode_t mode,
+ struct proc_dir_entry *parent)
+{
+ struct proc_dir_entry *p;
+ p = create_proc_entry(name, mode, parent);
+ if (p)
+ snd_info_entry_prepare(p);
+ return p;
+}
+
+int __init snd_info_init(void)
+{
+ struct proc_dir_entry *p;
+
+ p = snd_create_proc_entry("asound", S_IFDIR | S_IRUGO | S_IXUGO, &proc_root);
+ if (p == NULL)
+ return -ENOMEM;
+ snd_proc_root = p;
+#ifdef CONFIG_SND_OSSEMUL
+ {
+ snd_info_entry_t *entry;
+ if ((entry = snd_info_create_module_entry(THIS_MODULE, "oss", NULL)) == NULL)
+ return -ENOMEM;
+ entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
+ if (snd_info_register(entry) < 0) {
+ snd_info_free_entry(entry);
+ return -ENOMEM;
+ }
+ snd_oss_root = entry;
+ }
+#endif
+#if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
+ {
+ snd_info_entry_t *entry;
+ if ((entry = snd_info_create_module_entry(THIS_MODULE, "seq", NULL)) == NULL)
+ return -ENOMEM;
+ entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
+ if (snd_info_register(entry) < 0) {
+ snd_info_free_entry(entry);
+ return -ENOMEM;
+ }
+ snd_seq_root = entry;
+ }
+#endif
+ snd_info_version_init();
+ snd_memory_info_init();
+ snd_minor_info_init();
+ snd_minor_info_oss_init();
+ snd_card_info_init();
+ return 0;
+}
+
+int __exit snd_info_done(void)
+{
+ snd_card_info_done();
+ snd_minor_info_oss_done();
+ snd_minor_info_done();
+ snd_memory_info_done();
+ snd_info_version_done();
+ if (snd_proc_root) {
+#if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
+ if (snd_seq_root)
+ snd_info_unregister(snd_seq_root);
+#endif
+#ifdef CONFIG_SND_OSSEMUL
+ if (snd_oss_root)
+ snd_info_unregister(snd_oss_root);
+#endif
+ snd_remove_proc_entry(&proc_root, snd_proc_root);
+ }
+ return 0;
+}
+
+/*
+
+ */
+
+
+/*
+ * create a card proc file
+ * called from init.c
+ */
+int snd_info_card_create(snd_card_t * card)
+{
+ char str[8];
+ snd_info_entry_t *entry;
+
+ snd_assert(card != NULL, return -ENXIO);
+
+ sprintf(str, "card%i", card->number);
+ if ((entry = snd_info_create_module_entry(card->module, str, NULL)) == NULL)
+ return -ENOMEM;
+ entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
+ if (snd_info_register(entry) < 0) {
+ snd_info_free_entry(entry);
+ return -ENOMEM;
+ }
+ card->proc_root = entry;
+ return 0;
+}
+
+/*
+ * register the card proc file
+ * called from init.c
+ */
+int snd_info_card_register(snd_card_t * card)
+{
+ struct proc_dir_entry *p;
+
+ snd_assert(card != NULL, return -ENXIO);
+
+ if (!strcmp(card->id, card->proc_root->name))
+ return 0;
+
+ p = proc_symlink(card->id, snd_proc_root, card->proc_root->name);
+ if (p == NULL)
+ return -ENOMEM;
+ card->proc_root_link = p;
+ return 0;
+}
+
+/*
+ * de-register the card proc file
+ * called from init.c
+ */
+int snd_info_card_free(snd_card_t * card)
+{
+ snd_assert(card != NULL, return -ENXIO);
+ if (card->proc_root_link) {
+ snd_remove_proc_entry(snd_proc_root, card->proc_root_link);
+ card->proc_root_link = NULL;
+ }
+ if (card->proc_root) {
+ snd_info_unregister(card->proc_root);
+ card->proc_root = NULL;
+ }
+ return 0;
+}
+
+
+/**
+ * snd_info_get_line - read one line from the procfs buffer
+ * @buffer: the procfs buffer
+ * @line: the buffer to store
+ * @len: the max. buffer size - 1
+ *
+ * Reads one line from the buffer and stores the string.
+ *
+ * Returns zero if successful, or 1 if error or EOF.
+ */
+int snd_info_get_line(snd_info_buffer_t * buffer, char *line, int len)
+{
+ int c = -1;
+
+ if (len <= 0 || buffer->stop || buffer->error)
+ return 1;
+ while (--len > 0) {
+ c = *buffer->curr++;
+ if (c == '\n') {
+ if ((buffer->curr - buffer->buffer) >= (long)buffer->size) {
+ buffer->stop = 1;
+ }
+ break;
+ }
+ *line++ = c;
+ if ((buffer->curr - buffer->buffer) >= (long)buffer->size) {
+ buffer->stop = 1;
+ break;
+ }
+ }
+ while (c != '\n' && !buffer->stop) {
+ c = *buffer->curr++;
+ if ((buffer->curr - buffer->buffer) >= (long)buffer->size) {
+ buffer->stop = 1;
+ }
+ }
+ *line = '\0';
+ return 0;
+}
+
+/**
+ * snd_info_get_line - parse a string token
+ * @dest: the buffer to store the string token
+ * @src: the original string
+ * @len: the max. length of token - 1
+ *
+ * Parses the original string and copy a token to the given
+ * string buffer.
+ *
+ * Returns the updated pointer of the original string so that
+ * it can be used for the next call.
+ */
+char *snd_info_get_str(char *dest, char *src, int len)
+{
+ int c;
+
+ while (*src == ' ' || *src == '\t')
+ src++;
+ if (*src == '"' || *src == '\'') {
+ c = *src++;
+ while (--len > 0 && *src && *src != c) {
+ *dest++ = *src++;
+ }
+ if (*src == c)
+ src++;
+ } else {
+ while (--len > 0 && *src && *src != ' ' && *src != '\t') {
+ *dest++ = *src++;
+ }
+ }
+ *dest = 0;
+ while (*src == ' ' || *src == '\t')
+ src++;
+ return src;
+}
+
+/**
+ * snd_info_create_entry - create an info entry
+ * @name: the proc file name
+ *
+ * Creates an info entry with the given file name and initializes as
+ * the default state.
+ *
+ * Usually called from other functions such as
+ * snd_info_create_card_entry().
+ *
+ * Returns the pointer of the new instance, or NULL on failure.
+ */
+static snd_info_entry_t *snd_info_create_entry(const char *name)
+{
+ snd_info_entry_t *entry;
+ entry = kcalloc(1, sizeof(*entry), GFP_KERNEL);
+ if (entry == NULL)
+ return NULL;
+ entry->name = snd_kmalloc_strdup(name, GFP_KERNEL);
+ if (entry->name == NULL) {
+ kfree(entry);
+ return NULL;
+ }
+ entry->mode = S_IFREG | S_IRUGO;
+ entry->content = SNDRV_INFO_CONTENT_TEXT;
+ init_MUTEX(&entry->access);
+ return entry;
+}
+
+/**
+ * snd_info_create_module_entry - create an info entry for the given module
+ * @module: the module pointer
+ * @name: the file name
+ * @parent: the parent directory
+ *
+ * Creates a new info entry and assigns it to the given module.
+ *
+ * Returns the pointer of the new instance, or NULL on failure.
+ */
+snd_info_entry_t *snd_info_create_module_entry(struct module * module,
+ const char *name,
+ snd_info_entry_t *parent)
+{
+ snd_info_entry_t *entry = snd_info_create_entry(name);
+ if (entry) {
+ entry->module = module;
+ entry->parent = parent;
+ }
+ return entry;
+}
+
+/**
+ * snd_info_create_card_entry - create an info entry for the given card
+ * @card: the card instance
+ * @name: the file name
+ * @parent: the parent directory
+ *
+ * Creates a new info entry and assigns it to the given card.
+ *
+ * Returns the pointer of the new instance, or NULL on failure.
+ */
+snd_info_entry_t *snd_info_create_card_entry(snd_card_t * card,
+ const char *name,
+ snd_info_entry_t * parent)
+{
+ snd_info_entry_t *entry = snd_info_create_entry(name);
+ if (entry) {
+ entry->module = card->module;
+ entry->card = card;
+ entry->parent = parent;
+ }
+ return entry;
+}
+
+static int snd_info_dev_free_entry(snd_device_t *device)
+{
+ snd_info_entry_t *entry = device->device_data;
+ snd_info_free_entry(entry);
+ return 0;
+}
+
+static int snd_info_dev_register_entry(snd_device_t *device)
+{
+ snd_info_entry_t *entry = device->device_data;
+ return snd_info_register(entry);
+}
+
+static int snd_info_dev_disconnect_entry(snd_device_t *device)
+{
+ snd_info_entry_t *entry = device->device_data;
+ entry->disconnected = 1;
+ return 0;
+}
+
+static int snd_info_dev_unregister_entry(snd_device_t *device)
+{
+ snd_info_entry_t *entry = device->device_data;
+ return snd_info_unregister(entry);
+}
+
+/**
+ * snd_card_proc_new - create an info entry for the given card
+ * @card: the card instance
+ * @name: the file name
+ * @entryp: the pointer to store the new info entry
+ *
+ * Creates a new info entry and assigns it to the given card.
+ * Unlike snd_info_create_card_entry(), this function registers the
+ * info entry as an ALSA device component, so that it can be
+ * unregistered/released without explicit call.
+ * Also, you don't have to register this entry via snd_info_register(),
+ * since this will be registered by snd_card_register() automatically.
+ *
+ * The parent is assumed as card->proc_root.
+ *
+ * For releasing this entry, use snd_device_free() instead of
+ * snd_info_free_entry().
+ *
+ * Returns zero if successful, or a negative error code on failure.
+ */
+int snd_card_proc_new(snd_card_t *card, const char *name,
+ snd_info_entry_t **entryp)
+{
+ static snd_device_ops_t ops = {
+ .dev_free = snd_info_dev_free_entry,
+ .dev_register = snd_info_dev_register_entry,
+ .dev_disconnect = snd_info_dev_disconnect_entry,
+ .dev_unregister = snd_info_dev_unregister_entry
+ };
+ snd_info_entry_t *entry;
+ int err;
+
+ entry = snd_info_create_card_entry(card, name, card->proc_root);
+ if (! entry)
+ return -ENOMEM;
+ if ((err = snd_device_new(card, SNDRV_DEV_INFO, entry, &ops)) < 0) {
+ snd_info_free_entry(entry);
+ return err;
+ }
+ if (entryp)
+ *entryp = entry;
+ return 0;
+}
+
+/**
+ * snd_info_free_entry - release the info entry
+ * @entry: the info entry
+ *
+ * Releases the info entry. Don't call this after registered.
+ */
+void snd_info_free_entry(snd_info_entry_t * entry)
+{
+ if (entry == NULL)
+ return;
+ kfree(entry->name);
+ if (entry->private_free)
+ entry->private_free(entry);
+ kfree(entry);
+}
+
+/**
+ * snd_info_register - register the info entry
+ * @entry: the info entry
+ *
+ * Registers the proc info entry.
+ *
+ * Returns zero if successful, or a negative error code on failure.
+ */
+int snd_info_register(snd_info_entry_t * entry)
+{
+ struct proc_dir_entry *root, *p = NULL;
+
+ snd_assert(entry != NULL, return -ENXIO);
+ root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
+ down(&info_mutex);
+ p = snd_create_proc_entry(entry->name, entry->mode, root);
+ if (!p) {
+ up(&info_mutex);
+ return -ENOMEM;
+ }
+ p->owner = entry->module;
+ if (!S_ISDIR(entry->mode))
+ p->proc_fops = &snd_info_entry_operations;
+ p->size = entry->size;
+ p->data = entry;
+ entry->p = p;
+ up(&info_mutex);
+ return 0;
+}
+
+/**
+ * snd_info_unregister - de-register the info entry
+ * @entry: the info entry
+ *
+ * De-registers the info entry and releases the instance.
+ *
+ * Returns zero if successful, or a negative error code on failure.
+ */
+int snd_info_unregister(snd_info_entry_t * entry)
+{
+ struct proc_dir_entry *root;
+
+ snd_assert(entry != NULL && entry->p != NULL, return -ENXIO);
+ root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
+ snd_assert(root, return -ENXIO);
+ down(&info_mutex);
+ snd_remove_proc_entry(root, entry->p);
+ up(&info_mutex);
+ snd_info_free_entry(entry);
+ return 0;
+}
+
+/*
+
+ */
+
+static snd_info_entry_t *snd_info_version_entry = NULL;
+
+static void snd_info_version_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer)
+{
+ snd_iprintf(buffer,
+ "Advanced Linux Sound Architecture Driver Version "
+ CONFIG_SND_VERSION CONFIG_SND_DATE ".\n"
+ );
+}
+
+static int __init snd_info_version_init(void)
+{
+ snd_info_entry_t *entry;
+
+ entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL);
+ if (entry == NULL)
+ return -ENOMEM;
+ entry->c.text.read_size = 256;
+ entry->c.text.read = snd_info_version_read;
+ if (snd_info_register(entry) < 0) {
+ snd_info_free_entry(entry);
+ return -ENOMEM;
+ }
+ snd_info_version_entry = entry;
+ return 0;
+}
+
+static int __exit snd_info_version_done(void)
+{
+ if (snd_info_version_entry)
+ snd_info_unregister(snd_info_version_entry);
+ return 0;
+}
+
+#endif /* CONFIG_PROC_FS */