diff options
author | Tejun Heo <tj@kernel.org> | 2009-08-06 18:13:23 +0900 |
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committer | Takashi Iwai <tiwai@suse.de> | 2009-08-10 13:59:12 +0200 |
commit | 1905b1bfc0de6f69a61dc03cac0d86a04b3216bd (patch) | |
tree | 2accb0cdfa03c279ac610438500d614fb10419eb /fs/char_dev.c | |
parent | ed680c4ad478d0fee9740f7d029087f181346564 (diff) | |
download | linux-stable-1905b1bfc0de6f69a61dc03cac0d86a04b3216bd.tar.gz linux-stable-1905b1bfc0de6f69a61dc03cac0d86a04b3216bd.tar.bz2 linux-stable-1905b1bfc0de6f69a61dc03cac0d86a04b3216bd.zip |
chrdev: implement __[un]register_chrdev()
[un]register_chrdev() assume minor range 0-255. This patch adds __
prefixed versions which take @minorbase and @count explicitly.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'fs/char_dev.c')
-rw-r--r-- | fs/char_dev.c | 39 |
1 files changed, 26 insertions, 13 deletions
diff --git a/fs/char_dev.c b/fs/char_dev.c index a173551e19d7..2f18c1e4e301 100644 --- a/fs/char_dev.c +++ b/fs/char_dev.c @@ -237,8 +237,10 @@ int alloc_chrdev_region(dev_t *dev, unsigned baseminor, unsigned count, } /** - * register_chrdev() - Register a major number for character devices. + * __register_chrdev() - create and register a cdev occupying a range of minors * @major: major device number or 0 for dynamic allocation + * @baseminor: first of the requested range of minor numbers + * @count: the number of minor numbers required * @name: name of this range of devices * @fops: file operations associated with this devices * @@ -254,19 +256,17 @@ int alloc_chrdev_region(dev_t *dev, unsigned baseminor, unsigned count, * /dev. It only helps to keep track of the different owners of devices. If * your module name has only one type of devices it's ok to use e.g. the name * of the module here. - * - * This function registers a range of 256 minor numbers. The first minor number - * is 0. */ -int register_chrdev(unsigned int major, const char *name, - const struct file_operations *fops) +int __register_chrdev(unsigned int major, unsigned int baseminor, + unsigned int count, const char *name, + const struct file_operations *fops) { struct char_device_struct *cd; struct cdev *cdev; char *s; int err = -ENOMEM; - cd = __register_chrdev_region(major, 0, 256, name); + cd = __register_chrdev_region(major, baseminor, count, name); if (IS_ERR(cd)) return PTR_ERR(cd); @@ -280,7 +280,7 @@ int register_chrdev(unsigned int major, const char *name, for (s = strchr(kobject_name(&cdev->kobj),'/'); s; s = strchr(s, '/')) *s = '!'; - err = cdev_add(cdev, MKDEV(cd->major, 0), 256); + err = cdev_add(cdev, MKDEV(cd->major, baseminor), count); if (err) goto out; @@ -290,7 +290,7 @@ int register_chrdev(unsigned int major, const char *name, out: kobject_put(&cdev->kobj); out2: - kfree(__unregister_chrdev_region(cd->major, 0, 256)); + kfree(__unregister_chrdev_region(cd->major, baseminor, count)); return err; } @@ -316,10 +316,23 @@ void unregister_chrdev_region(dev_t from, unsigned count) } } -void unregister_chrdev(unsigned int major, const char *name) +/** + * __unregister_chrdev - unregister and destroy a cdev + * @major: major device number + * @baseminor: first of the range of minor numbers + * @count: the number of minor numbers this cdev is occupying + * @name: name of this range of devices + * + * Unregister and destroy the cdev occupying the region described by + * @major, @baseminor and @count. This function undoes what + * __register_chrdev() did. + */ +void __unregister_chrdev(unsigned int major, unsigned int baseminor, + unsigned int count, const char *name) { struct char_device_struct *cd; - cd = __unregister_chrdev_region(major, 0, 256); + + cd = __unregister_chrdev_region(major, baseminor, count); if (cd && cd->cdev) cdev_del(cd->cdev); kfree(cd); @@ -568,6 +581,6 @@ EXPORT_SYMBOL(cdev_alloc); EXPORT_SYMBOL(cdev_del); EXPORT_SYMBOL(cdev_add); EXPORT_SYMBOL(cdev_index); -EXPORT_SYMBOL(register_chrdev); -EXPORT_SYMBOL(unregister_chrdev); +EXPORT_SYMBOL(__register_chrdev); +EXPORT_SYMBOL(__unregister_chrdev); EXPORT_SYMBOL(directly_mappable_cdev_bdi); |