diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/telephony/phonedev.c |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/telephony/phonedev.c')
-rw-r--r-- | drivers/telephony/phonedev.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/drivers/telephony/phonedev.c b/drivers/telephony/phonedev.c new file mode 100644 index 000000000000..3c987f49f6b4 --- /dev/null +++ b/drivers/telephony/phonedev.c @@ -0,0 +1,170 @@ +/* + * Telephony registration for Linux + * + * (c) Copyright 1999 Red Hat Software Inc. + * + * 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. + * + * Author: Alan Cox, <alan@redhat.com> + * + * Fixes: Mar 01 2000 Thomas Sparr, <thomas.l.sparr@telia.com> + * phone_register_device now works with unit!=PHONE_UNIT_ANY + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/fs.h> +#include <linux/mm.h> +#include <linux/string.h> +#include <linux/errno.h> +#include <linux/phonedev.h> +#include <linux/init.h> +#include <asm/uaccess.h> +#include <asm/system.h> + +#include <linux/kmod.h> +#include <linux/sem.h> +#include <linux/devfs_fs_kernel.h> + +#define PHONE_NUM_DEVICES 256 + +/* + * Active devices + */ + +static struct phone_device *phone_device[PHONE_NUM_DEVICES]; +static DECLARE_MUTEX(phone_lock); + +/* + * Open a phone device. + */ + +static int phone_open(struct inode *inode, struct file *file) +{ + unsigned int minor = iminor(inode); + int err = 0; + struct phone_device *p; + struct file_operations *old_fops, *new_fops = NULL; + + if (minor >= PHONE_NUM_DEVICES) + return -ENODEV; + + down(&phone_lock); + p = phone_device[minor]; + if (p) + new_fops = fops_get(p->f_op); + if (!new_fops) { + up(&phone_lock); + request_module("char-major-%d-%d", PHONE_MAJOR, minor); + down(&phone_lock); + p = phone_device[minor]; + if (p == NULL || (new_fops = fops_get(p->f_op)) == NULL) + { + err=-ENODEV; + goto end; + } + } + old_fops = file->f_op; + file->f_op = new_fops; + if (p->open) + err = p->open(p, file); /* Tell the device it is open */ + if (err) { + fops_put(file->f_op); + file->f_op = fops_get(old_fops); + } + fops_put(old_fops); +end: + up(&phone_lock); + return err; +} + +/* + * Telephony For Linux device drivers request registration here. + */ + +int phone_register_device(struct phone_device *p, int unit) +{ + int base; + int end; + int i; + + base = 0; + end = PHONE_NUM_DEVICES - 1; + + if (unit != PHONE_UNIT_ANY) { + base = unit; + end = unit + 1; /* enter the loop at least one time */ + } + + down(&phone_lock); + for (i = base; i < end; i++) { + if (phone_device[i] == NULL) { + phone_device[i] = p; + p->minor = i; + devfs_mk_cdev(MKDEV(PHONE_MAJOR,i), + S_IFCHR|S_IRUSR|S_IWUSR, "phone/%d", i); + up(&phone_lock); + return 0; + } + } + up(&phone_lock); + return -ENFILE; +} + +/* + * Unregister an unused Telephony for linux device + */ + +void phone_unregister_device(struct phone_device *pfd) +{ + down(&phone_lock); + if (phone_device[pfd->minor] != pfd) + panic("phone: bad unregister"); + devfs_remove("phone/%d", pfd->minor); + phone_device[pfd->minor] = NULL; + up(&phone_lock); +} + + +static struct file_operations phone_fops = +{ + .owner = THIS_MODULE, + .open = phone_open, +}; + +/* + * Board init functions + */ + + +/* + * Initialise Telephony for linux + */ + +static int __init telephony_init(void) +{ + printk(KERN_INFO "Linux telephony interface: v1.00\n"); + if (register_chrdev(PHONE_MAJOR, "telephony", &phone_fops)) { + printk("phonedev: unable to get major %d\n", PHONE_MAJOR); + return -EIO; + } + + return 0; +} + +static void __exit telephony_exit(void) +{ + unregister_chrdev(PHONE_MAJOR, "telephony"); +} + +module_init(telephony_init); +module_exit(telephony_exit); + +MODULE_LICENSE("GPL"); + +EXPORT_SYMBOL(phone_register_device); +EXPORT_SYMBOL(phone_unregister_device); |