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-rw-r--r--sound/core/info.c920
1 files changed, 920 insertions, 0 deletions
diff --git a/sound/core/info.c b/sound/core/info.c
new file mode 100644
index 000000000..e2f302e55
--- /dev/null
+++ b/sound/core/info.c
@@ -0,0 +1,920 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Information interface for ALSA driver
+ * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
+ */
+
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/module.h>
+#include <sound/core.h>
+#include <sound/minors.h>
+#include <sound/info.h>
+#include <linux/utsname.h>
+#include <linux/proc_fs.h>
+#include <linux/mutex.h>
+
+int snd_info_check_reserved_words(const char *str)
+{
+ static const char * const reserved[] =
+ {
+ "version",
+ "meminfo",
+ "memdebug",
+ "detect",
+ "devices",
+ "oss",
+ "cards",
+ "timers",
+ "synth",
+ "pcm",
+ "seq",
+ NULL
+ };
+ const char * const *xstr = reserved;
+
+ while (*xstr) {
+ if (!strcmp(*xstr, str))
+ return 0;
+ xstr++;
+ }
+ if (!strncmp(str, "card", 4))
+ return 0;
+ return 1;
+}
+
+static DEFINE_MUTEX(info_mutex);
+
+struct snd_info_private_data {
+ struct snd_info_buffer *rbuffer;
+ struct snd_info_buffer *wbuffer;
+ struct snd_info_entry *entry;
+ void *file_private_data;
+};
+
+static int snd_info_version_init(void);
+static void snd_info_clear_entries(struct snd_info_entry *entry);
+
+/*
+
+ */
+
+static struct snd_info_entry *snd_proc_root;
+struct snd_info_entry *snd_seq_root;
+EXPORT_SYMBOL(snd_seq_root);
+
+#ifdef CONFIG_SND_OSSEMUL
+struct snd_info_entry *snd_oss_root;
+#endif
+
+static int alloc_info_private(struct snd_info_entry *entry,
+ struct snd_info_private_data **ret)
+{
+ struct snd_info_private_data *data;
+
+ if (!entry || !entry->p)
+ return -ENODEV;
+ if (!try_module_get(entry->module))
+ return -EFAULT;
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data) {
+ module_put(entry->module);
+ return -ENOMEM;
+ }
+ data->entry = entry;
+ *ret = data;
+ return 0;
+}
+
+static bool valid_pos(loff_t pos, size_t count)
+{
+ if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
+ return false;
+ if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
+ return false;
+ return true;
+}
+
+/*
+ * file ops for binary proc files
+ */
+static loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig)
+{
+ struct snd_info_private_data *data;
+ struct snd_info_entry *entry;
+ loff_t ret = -EINVAL, size;
+
+ data = file->private_data;
+ entry = data->entry;
+ mutex_lock(&entry->access);
+ if (entry->c.ops->llseek) {
+ ret = entry->c.ops->llseek(entry,
+ data->file_private_data,
+ file, offset, orig);
+ goto out;
+ }
+
+ size = entry->size;
+ switch (orig) {
+ case SEEK_SET:
+ break;
+ case SEEK_CUR:
+ offset += file->f_pos;
+ break;
+ case SEEK_END:
+ if (!size)
+ goto out;
+ offset += size;
+ break;
+ default:
+ goto out;
+ }
+ if (offset < 0)
+ goto out;
+ if (size && offset > size)
+ offset = size;
+ file->f_pos = offset;
+ ret = offset;
+ out:
+ mutex_unlock(&entry->access);
+ return ret;
+}
+
+static ssize_t snd_info_entry_read(struct file *file, char __user *buffer,
+ size_t count, loff_t * offset)
+{
+ struct snd_info_private_data *data = file->private_data;
+ struct snd_info_entry *entry = data->entry;
+ size_t size;
+ loff_t pos;
+
+ pos = *offset;
+ if (!valid_pos(pos, count))
+ return -EIO;
+ if (pos >= entry->size)
+ return 0;
+ size = entry->size - pos;
+ size = min(count, size);
+ size = entry->c.ops->read(entry, data->file_private_data,
+ file, buffer, size, pos);
+ 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)
+{
+ struct snd_info_private_data *data = file->private_data;
+ struct snd_info_entry *entry = data->entry;
+ ssize_t size = 0;
+ loff_t pos;
+
+ pos = *offset;
+ if (!valid_pos(pos, count))
+ return -EIO;
+ if (count > 0) {
+ size_t maxsize = entry->size - pos;
+ count = min(count, maxsize);
+ size = entry->c.ops->write(entry, data->file_private_data,
+ file, buffer, count, pos);
+ }
+ if (size > 0)
+ *offset = pos + size;
+ return size;
+}
+
+static __poll_t snd_info_entry_poll(struct file *file, poll_table *wait)
+{
+ struct snd_info_private_data *data = file->private_data;
+ struct snd_info_entry *entry = data->entry;
+ __poll_t mask = 0;
+
+ if (entry->c.ops->poll)
+ return entry->c.ops->poll(entry,
+ data->file_private_data,
+ file, wait);
+ if (entry->c.ops->read)
+ mask |= EPOLLIN | EPOLLRDNORM;
+ if (entry->c.ops->write)
+ mask |= EPOLLOUT | EPOLLWRNORM;
+ return mask;
+}
+
+static long snd_info_entry_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ struct snd_info_private_data *data = file->private_data;
+ struct snd_info_entry *entry = data->entry;
+
+ if (!entry->c.ops->ioctl)
+ return -ENOTTY;
+ return entry->c.ops->ioctl(entry, data->file_private_data,
+ file, cmd, arg);
+}
+
+static int snd_info_entry_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct inode *inode = file_inode(file);
+ struct snd_info_private_data *data;
+ struct snd_info_entry *entry;
+
+ data = file->private_data;
+ if (data == NULL)
+ return 0;
+ entry = data->entry;
+ if (!entry->c.ops->mmap)
+ return -ENXIO;
+ return entry->c.ops->mmap(entry, data->file_private_data,
+ inode, file, vma);
+}
+
+static int snd_info_entry_open(struct inode *inode, struct file *file)
+{
+ struct snd_info_entry *entry = pde_data(inode);
+ struct snd_info_private_data *data;
+ int mode, err;
+
+ mutex_lock(&info_mutex);
+ err = alloc_info_private(entry, &data);
+ if (err < 0)
+ goto unlock;
+
+ mode = file->f_flags & O_ACCMODE;
+ if (((mode == O_RDONLY || mode == O_RDWR) && !entry->c.ops->read) ||
+ ((mode == O_WRONLY || mode == O_RDWR) && !entry->c.ops->write)) {
+ err = -ENODEV;
+ goto error;
+ }
+
+ if (entry->c.ops->open) {
+ err = entry->c.ops->open(entry, mode, &data->file_private_data);
+ if (err < 0)
+ goto error;
+ }
+
+ file->private_data = data;
+ mutex_unlock(&info_mutex);
+ return 0;
+
+ error:
+ kfree(data);
+ module_put(entry->module);
+ unlock:
+ mutex_unlock(&info_mutex);
+ return err;
+}
+
+static int snd_info_entry_release(struct inode *inode, struct file *file)
+{
+ struct snd_info_private_data *data = file->private_data;
+ struct snd_info_entry *entry = data->entry;
+
+ if (entry->c.ops->release)
+ entry->c.ops->release(entry, file->f_flags & O_ACCMODE,
+ data->file_private_data);
+ module_put(entry->module);
+ kfree(data);
+ return 0;
+}
+
+static const struct proc_ops snd_info_entry_operations =
+{
+ .proc_lseek = snd_info_entry_llseek,
+ .proc_read = snd_info_entry_read,
+ .proc_write = snd_info_entry_write,
+ .proc_poll = snd_info_entry_poll,
+ .proc_ioctl = snd_info_entry_ioctl,
+ .proc_mmap = snd_info_entry_mmap,
+ .proc_open = snd_info_entry_open,
+ .proc_release = snd_info_entry_release,
+};
+
+/*
+ * file ops for text proc files
+ */
+static ssize_t snd_info_text_entry_write(struct file *file,
+ const char __user *buffer,
+ size_t count, loff_t *offset)
+{
+ struct seq_file *m = file->private_data;
+ struct snd_info_private_data *data = m->private;
+ struct snd_info_entry *entry = data->entry;
+ struct snd_info_buffer *buf;
+ loff_t pos;
+ size_t next;
+ int err = 0;
+
+ if (!entry->c.text.write)
+ return -EIO;
+ pos = *offset;
+ if (!valid_pos(pos, count))
+ return -EIO;
+ next = pos + count;
+ /* don't handle too large text inputs */
+ if (next > 16 * 1024)
+ return -EIO;
+ mutex_lock(&entry->access);
+ buf = data->wbuffer;
+ if (!buf) {
+ data->wbuffer = buf = kzalloc(sizeof(*buf), GFP_KERNEL);
+ if (!buf) {
+ err = -ENOMEM;
+ goto error;
+ }
+ }
+ if (next > buf->len) {
+ char *nbuf = kvzalloc(PAGE_ALIGN(next), GFP_KERNEL);
+ if (!nbuf) {
+ err = -ENOMEM;
+ goto error;
+ }
+ kvfree(buf->buffer);
+ buf->buffer = nbuf;
+ buf->len = PAGE_ALIGN(next);
+ }
+ if (copy_from_user(buf->buffer + pos, buffer, count)) {
+ err = -EFAULT;
+ goto error;
+ }
+ buf->size = next;
+ error:
+ mutex_unlock(&entry->access);
+ if (err < 0)
+ return err;
+ *offset = next;
+ return count;
+}
+
+static int snd_info_seq_show(struct seq_file *seq, void *p)
+{
+ struct snd_info_private_data *data = seq->private;
+ struct snd_info_entry *entry = data->entry;
+
+ if (!entry->c.text.read) {
+ return -EIO;
+ } else {
+ data->rbuffer->buffer = (char *)seq; /* XXX hack! */
+ entry->c.text.read(entry, data->rbuffer);
+ }
+ return 0;
+}
+
+static int snd_info_text_entry_open(struct inode *inode, struct file *file)
+{
+ struct snd_info_entry *entry = pde_data(inode);
+ struct snd_info_private_data *data;
+ int err;
+
+ mutex_lock(&info_mutex);
+ err = alloc_info_private(entry, &data);
+ if (err < 0)
+ goto unlock;
+
+ data->rbuffer = kzalloc(sizeof(*data->rbuffer), GFP_KERNEL);
+ if (!data->rbuffer) {
+ err = -ENOMEM;
+ goto error;
+ }
+ if (entry->size)
+ err = single_open_size(file, snd_info_seq_show, data,
+ entry->size);
+ else
+ err = single_open(file, snd_info_seq_show, data);
+ if (err < 0)
+ goto error;
+ mutex_unlock(&info_mutex);
+ return 0;
+
+ error:
+ kfree(data->rbuffer);
+ kfree(data);
+ module_put(entry->module);
+ unlock:
+ mutex_unlock(&info_mutex);
+ return err;
+}
+
+static int snd_info_text_entry_release(struct inode *inode, struct file *file)
+{
+ struct seq_file *m = file->private_data;
+ struct snd_info_private_data *data = m->private;
+ struct snd_info_entry *entry = data->entry;
+
+ if (data->wbuffer && entry->c.text.write)
+ entry->c.text.write(entry, data->wbuffer);
+
+ single_release(inode, file);
+ kfree(data->rbuffer);
+ if (data->wbuffer) {
+ kvfree(data->wbuffer->buffer);
+ kfree(data->wbuffer);
+ }
+
+ module_put(entry->module);
+ kfree(data);
+ return 0;
+}
+
+static const struct proc_ops snd_info_text_entry_ops =
+{
+ .proc_open = snd_info_text_entry_open,
+ .proc_release = snd_info_text_entry_release,
+ .proc_write = snd_info_text_entry_write,
+ .proc_lseek = seq_lseek,
+ .proc_read = seq_read,
+};
+
+static struct snd_info_entry *create_subdir(struct module *mod,
+ const char *name)
+{
+ struct snd_info_entry *entry;
+
+ entry = snd_info_create_module_entry(mod, name, NULL);
+ if (!entry)
+ return NULL;
+ entry->mode = S_IFDIR | 0555;
+ if (snd_info_register(entry) < 0) {
+ snd_info_free_entry(entry);
+ return NULL;
+ }
+ return entry;
+}
+
+static struct snd_info_entry *
+snd_info_create_entry(const char *name, struct snd_info_entry *parent,
+ struct module *module);
+
+int __init snd_info_init(void)
+{
+ snd_proc_root = snd_info_create_entry("asound", NULL, THIS_MODULE);
+ if (!snd_proc_root)
+ return -ENOMEM;
+ snd_proc_root->mode = S_IFDIR | 0555;
+ snd_proc_root->p = proc_mkdir("asound", NULL);
+ if (!snd_proc_root->p)
+ goto error;
+#ifdef CONFIG_SND_OSSEMUL
+ snd_oss_root = create_subdir(THIS_MODULE, "oss");
+ if (!snd_oss_root)
+ goto error;
+#endif
+#if IS_ENABLED(CONFIG_SND_SEQUENCER)
+ snd_seq_root = create_subdir(THIS_MODULE, "seq");
+ if (!snd_seq_root)
+ goto error;
+#endif
+ if (snd_info_version_init() < 0 ||
+ snd_minor_info_init() < 0 ||
+ snd_minor_info_oss_init() < 0 ||
+ snd_card_info_init() < 0 ||
+ snd_info_minor_register() < 0)
+ goto error;
+ return 0;
+
+ error:
+ snd_info_free_entry(snd_proc_root);
+ return -ENOMEM;
+}
+
+int __exit snd_info_done(void)
+{
+ snd_info_free_entry(snd_proc_root);
+ return 0;
+}
+
+static void snd_card_id_read(struct snd_info_entry *entry,
+ struct snd_info_buffer *buffer)
+{
+ struct snd_card *card = entry->private_data;
+
+ snd_iprintf(buffer, "%s\n", card->id);
+}
+
+/*
+ * create a card proc file
+ * called from init.c
+ */
+int snd_info_card_create(struct snd_card *card)
+{
+ char str[8];
+ struct snd_info_entry *entry;
+
+ if (snd_BUG_ON(!card))
+ return -ENXIO;
+
+ sprintf(str, "card%i", card->number);
+ entry = create_subdir(card->module, str);
+ if (!entry)
+ return -ENOMEM;
+ card->proc_root = entry;
+
+ return snd_card_ro_proc_new(card, "id", card, snd_card_id_read);
+}
+
+/*
+ * register the card proc file
+ * called from init.c
+ * can be called multiple times for reinitialization
+ */
+int snd_info_card_register(struct snd_card *card)
+{
+ struct proc_dir_entry *p;
+ int err;
+
+ if (snd_BUG_ON(!card))
+ return -ENXIO;
+
+ err = snd_info_register(card->proc_root);
+ if (err < 0)
+ return err;
+
+ if (!strcmp(card->id, card->proc_root->name))
+ return 0;
+
+ if (card->proc_root_link)
+ return 0;
+ p = proc_symlink(card->id, snd_proc_root->p, card->proc_root->name);
+ if (!p)
+ return -ENOMEM;
+ card->proc_root_link = p;
+ return 0;
+}
+
+/*
+ * called on card->id change
+ */
+void snd_info_card_id_change(struct snd_card *card)
+{
+ mutex_lock(&info_mutex);
+ if (card->proc_root_link) {
+ proc_remove(card->proc_root_link);
+ card->proc_root_link = NULL;
+ }
+ if (strcmp(card->id, card->proc_root->name))
+ card->proc_root_link = proc_symlink(card->id,
+ snd_proc_root->p,
+ card->proc_root->name);
+ mutex_unlock(&info_mutex);
+}
+
+/*
+ * de-register the card proc file
+ * called from init.c
+ */
+void snd_info_card_disconnect(struct snd_card *card)
+{
+ if (!card)
+ return;
+
+ proc_remove(card->proc_root_link);
+ if (card->proc_root)
+ proc_remove(card->proc_root->p);
+
+ mutex_lock(&info_mutex);
+ if (card->proc_root)
+ snd_info_clear_entries(card->proc_root);
+ card->proc_root_link = NULL;
+ card->proc_root = NULL;
+ mutex_unlock(&info_mutex);
+}
+
+/*
+ * release the card proc file resources
+ * called from init.c
+ */
+int snd_info_card_free(struct snd_card *card)
+{
+ if (!card)
+ return 0;
+ snd_info_free_entry(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
+ *
+ * Reads one line from the buffer and stores the string.
+ *
+ * Return: Zero if successful, or 1 if error or EOF.
+ */
+int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len)
+{
+ int c;
+
+ if (snd_BUG_ON(!buffer))
+ return 1;
+ if (!buffer->buffer)
+ return 1;
+ if (len <= 0 || buffer->stop || buffer->error)
+ return 1;
+ while (!buffer->stop) {
+ c = buffer->buffer[buffer->curr++];
+ if (buffer->curr >= buffer->size)
+ buffer->stop = 1;
+ if (c == '\n')
+ break;
+ if (len > 1) {
+ len--;
+ *line++ = c;
+ }
+ }
+ *line = '\0';
+ return 0;
+}
+EXPORT_SYMBOL(snd_info_get_line);
+
+/**
+ * snd_info_get_str - 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.
+ *
+ * Return: The updated pointer of the original string so that
+ * it can be used for the next call.
+ */
+const char *snd_info_get_str(char *dest, const 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;
+}
+EXPORT_SYMBOL(snd_info_get_str);
+
+/*
+ * snd_info_create_entry - create an info entry
+ * @name: the proc file name
+ * @parent: the parent directory
+ *
+ * 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().
+ *
+ * Return: The pointer of the new instance, or %NULL on failure.
+ */
+static struct snd_info_entry *
+snd_info_create_entry(const char *name, struct snd_info_entry *parent,
+ struct module *module)
+{
+ struct snd_info_entry *entry;
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ if (entry == NULL)
+ return NULL;
+ entry->name = kstrdup(name, GFP_KERNEL);
+ if (entry->name == NULL) {
+ kfree(entry);
+ return NULL;
+ }
+ entry->mode = S_IFREG | 0444;
+ entry->content = SNDRV_INFO_CONTENT_TEXT;
+ mutex_init(&entry->access);
+ INIT_LIST_HEAD(&entry->children);
+ INIT_LIST_HEAD(&entry->list);
+ entry->parent = parent;
+ entry->module = module;
+ if (parent) {
+ mutex_lock(&parent->access);
+ list_add_tail(&entry->list, &parent->children);
+ mutex_unlock(&parent->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.
+ *
+ * Return: The pointer of the new instance, or %NULL on failure.
+ */
+struct snd_info_entry *snd_info_create_module_entry(struct module * module,
+ const char *name,
+ struct snd_info_entry *parent)
+{
+ if (!parent)
+ parent = snd_proc_root;
+ return snd_info_create_entry(name, parent, module);
+}
+EXPORT_SYMBOL(snd_info_create_module_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.
+ *
+ * Return: The pointer of the new instance, or %NULL on failure.
+ */
+struct snd_info_entry *snd_info_create_card_entry(struct snd_card *card,
+ const char *name,
+ struct snd_info_entry * parent)
+{
+ if (!parent)
+ parent = card->proc_root;
+ return snd_info_create_entry(name, parent, card->module);
+}
+EXPORT_SYMBOL(snd_info_create_card_entry);
+
+static void snd_info_clear_entries(struct snd_info_entry *entry)
+{
+ struct snd_info_entry *p;
+
+ if (!entry->p)
+ return;
+ list_for_each_entry(p, &entry->children, list)
+ snd_info_clear_entries(p);
+ entry->p = NULL;
+}
+
+/**
+ * snd_info_free_entry - release the info entry
+ * @entry: the info entry
+ *
+ * Releases the info entry.
+ */
+void snd_info_free_entry(struct snd_info_entry * entry)
+{
+ struct snd_info_entry *p, *n;
+
+ if (!entry)
+ return;
+ if (entry->p) {
+ proc_remove(entry->p);
+ mutex_lock(&info_mutex);
+ snd_info_clear_entries(entry);
+ mutex_unlock(&info_mutex);
+ }
+
+ /* free all children at first */
+ list_for_each_entry_safe(p, n, &entry->children, list)
+ snd_info_free_entry(p);
+
+ p = entry->parent;
+ if (p) {
+ mutex_lock(&p->access);
+ list_del(&entry->list);
+ mutex_unlock(&p->access);
+ }
+ kfree(entry->name);
+ if (entry->private_free)
+ entry->private_free(entry);
+ kfree(entry);
+}
+EXPORT_SYMBOL(snd_info_free_entry);
+
+static int __snd_info_register(struct snd_info_entry *entry)
+{
+ struct proc_dir_entry *root, *p = NULL;
+
+ if (snd_BUG_ON(!entry))
+ return -ENXIO;
+ root = entry->parent == NULL ? snd_proc_root->p : entry->parent->p;
+ mutex_lock(&info_mutex);
+ if (entry->p || !root)
+ goto unlock;
+ if (S_ISDIR(entry->mode)) {
+ p = proc_mkdir_mode(entry->name, entry->mode, root);
+ if (!p) {
+ mutex_unlock(&info_mutex);
+ return -ENOMEM;
+ }
+ } else {
+ const struct proc_ops *ops;
+ if (entry->content == SNDRV_INFO_CONTENT_DATA)
+ ops = &snd_info_entry_operations;
+ else
+ ops = &snd_info_text_entry_ops;
+ p = proc_create_data(entry->name, entry->mode, root,
+ ops, entry);
+ if (!p) {
+ mutex_unlock(&info_mutex);
+ return -ENOMEM;
+ }
+ proc_set_size(p, entry->size);
+ }
+ entry->p = p;
+ unlock:
+ mutex_unlock(&info_mutex);
+ return 0;
+}
+
+/**
+ * snd_info_register - register the info entry
+ * @entry: the info entry
+ *
+ * Registers the proc info entry.
+ * The all children entries are registered recursively.
+ *
+ * Return: Zero if successful, or a negative error code on failure.
+ */
+int snd_info_register(struct snd_info_entry *entry)
+{
+ struct snd_info_entry *p;
+ int err;
+
+ if (!entry->p) {
+ err = __snd_info_register(entry);
+ if (err < 0)
+ return err;
+ }
+
+ list_for_each_entry(p, &entry->children, list) {
+ err = snd_info_register(p);
+ if (err < 0)
+ return err;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(snd_info_register);
+
+/**
+ * snd_card_rw_proc_new - Create a read/write text proc file entry for the card
+ * @card: the card instance
+ * @name: the file name
+ * @private_data: the arbitrary private data
+ * @read: the read callback
+ * @write: the write callback, NULL for read-only
+ *
+ * This proc file entry will be registered via snd_card_register() call, and
+ * it will be removed automatically at the card removal, too.
+ *
+ * Return: zero if successful, or a negative error code
+ */
+int snd_card_rw_proc_new(struct snd_card *card, const char *name,
+ void *private_data,
+ void (*read)(struct snd_info_entry *,
+ struct snd_info_buffer *),
+ void (*write)(struct snd_info_entry *entry,
+ struct snd_info_buffer *buffer))
+{
+ struct snd_info_entry *entry;
+
+ entry = snd_info_create_card_entry(card, name, card->proc_root);
+ if (!entry)
+ return -ENOMEM;
+ snd_info_set_text_ops(entry, private_data, read);
+ if (write) {
+ entry->mode |= 0200;
+ entry->c.text.write = write;
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(snd_card_rw_proc_new);
+
+/*
+
+ */
+
+static void snd_info_version_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
+{
+ snd_iprintf(buffer,
+ "Advanced Linux Sound Architecture Driver Version k%s.\n",
+ init_utsname()->release);
+}
+
+static int __init snd_info_version_init(void)
+{
+ struct snd_info_entry *entry;
+
+ entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL);
+ if (entry == NULL)
+ return -ENOMEM;
+ entry->c.text.read = snd_info_version_read;
+ return snd_info_register(entry); /* freed in error path */
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-02 12:19:25 +0000