diff options
Diffstat (limited to 'drivers/uio/uio.c')
| -rw-r--r-- | drivers/uio/uio.c | 43 |
1 files changed, 37 insertions, 6 deletions
diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c index 0fd2cda..3d4d65b 100644 --- a/drivers/uio/uio.c +++ b/drivers/uio/uio.c @@ -23,9 +23,10 @@ #include <linux/sched.h> #include <linux/string.h> #include <linux/kobject.h> +#include <linux/cdev.h> #include <linux/uio_driver.h> -#define UIO_MAX_DEVICES 255 +#define UIO_MAX_DEVICES (1U << MINORBITS) struct uio_device { struct module *owner; @@ -41,6 +42,7 @@ struct uio_device { }; static int uio_major; +static struct cdev *uio_cdev; static DEFINE_IDR(uio_idr); static const struct file_operations uio_fops; @@ -731,15 +733,44 @@ static const struct file_operations uio_fops = { static int uio_major_init(void) { - uio_major = register_chrdev(0, "uio", &uio_fops); - if (uio_major < 0) - return uio_major; - return 0; + static const char name[] = "uio"; + struct cdev *cdev = NULL; + dev_t uio_dev = 0; + int result; + + result = alloc_chrdev_region(&uio_dev, 0, UIO_MAX_DEVICES, name); + if (result) + goto out; + + result = -ENOMEM; + cdev = cdev_alloc(); + if (!cdev) + goto out_unregister; + + cdev->owner = THIS_MODULE; + cdev->ops = &uio_fops; + kobject_set_name(&cdev->kobj, "%s", name); + + result = cdev_add(cdev, uio_dev, UIO_MAX_DEVICES); + if (result) + goto out_put; + + uio_major = MAJOR(uio_dev); + uio_cdev = cdev; + result = 0; +out: + return result; +out_put: + kobject_put(&cdev->kobj); +out_unregister: + unregister_chrdev_region(uio_dev, UIO_MAX_DEVICES); + goto out; } static void uio_major_cleanup(void) { - unregister_chrdev(uio_major, "uio"); + unregister_chrdev_region(MKDEV(uio_major, 0), UIO_MAX_DEVICES); + cdev_del(uio_cdev); } static int init_uio_class(void) |