133 lines
2.9 KiB
C
133 lines
2.9 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Copyright IBM Corp. 2004
|
|
*
|
|
* Tape class device support
|
|
*
|
|
* Author: Stefan Bader <shbader@de.ibm.com>
|
|
* Based on simple class device code by Greg K-H
|
|
*/
|
|
|
|
#define KMSG_COMPONENT "tape"
|
|
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
|
|
|
|
#include <linux/slab.h>
|
|
|
|
#include "tape_class.h"
|
|
|
|
MODULE_AUTHOR("Stefan Bader <shbader@de.ibm.com>");
|
|
MODULE_DESCRIPTION(
|
|
"Copyright IBM Corp. 2004 All Rights Reserved.\n"
|
|
"tape_class.c"
|
|
);
|
|
MODULE_LICENSE("GPL");
|
|
|
|
static struct class *tape_class;
|
|
|
|
/*
|
|
* Register a tape device and return a pointer to the cdev structure.
|
|
*
|
|
* device
|
|
* The pointer to the struct device of the physical (base) device.
|
|
* drivername
|
|
* The pointer to the drivers name for it's character devices.
|
|
* dev
|
|
* The intended major/minor number. The major number may be 0 to
|
|
* get a dynamic major number.
|
|
* fops
|
|
* The pointer to the drivers file operations for the tape device.
|
|
* devname
|
|
* The pointer to the name of the character device.
|
|
*/
|
|
struct tape_class_device *register_tape_dev(
|
|
struct device * device,
|
|
dev_t dev,
|
|
const struct file_operations *fops,
|
|
char * device_name,
|
|
char * mode_name)
|
|
{
|
|
struct tape_class_device * tcd;
|
|
int rc;
|
|
char * s;
|
|
|
|
tcd = kzalloc(sizeof(struct tape_class_device), GFP_KERNEL);
|
|
if (!tcd)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
strlcpy(tcd->device_name, device_name, TAPECLASS_NAME_LEN);
|
|
for (s = strchr(tcd->device_name, '/'); s; s = strchr(s, '/'))
|
|
*s = '!';
|
|
strlcpy(tcd->mode_name, mode_name, TAPECLASS_NAME_LEN);
|
|
for (s = strchr(tcd->mode_name, '/'); s; s = strchr(s, '/'))
|
|
*s = '!';
|
|
|
|
tcd->char_device = cdev_alloc();
|
|
if (!tcd->char_device) {
|
|
rc = -ENOMEM;
|
|
goto fail_with_tcd;
|
|
}
|
|
|
|
tcd->char_device->owner = fops->owner;
|
|
tcd->char_device->ops = fops;
|
|
|
|
rc = cdev_add(tcd->char_device, dev, 1);
|
|
if (rc)
|
|
goto fail_with_cdev;
|
|
|
|
tcd->class_device = device_create(tape_class, device,
|
|
tcd->char_device->dev, NULL,
|
|
"%s", tcd->device_name);
|
|
rc = PTR_ERR_OR_ZERO(tcd->class_device);
|
|
if (rc)
|
|
goto fail_with_cdev;
|
|
rc = sysfs_create_link(
|
|
&device->kobj,
|
|
&tcd->class_device->kobj,
|
|
tcd->mode_name
|
|
);
|
|
if (rc)
|
|
goto fail_with_class_device;
|
|
|
|
return tcd;
|
|
|
|
fail_with_class_device:
|
|
device_destroy(tape_class, tcd->char_device->dev);
|
|
|
|
fail_with_cdev:
|
|
cdev_del(tcd->char_device);
|
|
|
|
fail_with_tcd:
|
|
kfree(tcd);
|
|
|
|
return ERR_PTR(rc);
|
|
}
|
|
EXPORT_SYMBOL(register_tape_dev);
|
|
|
|
void unregister_tape_dev(struct device *device, struct tape_class_device *tcd)
|
|
{
|
|
if (tcd != NULL && !IS_ERR(tcd)) {
|
|
sysfs_remove_link(&device->kobj, tcd->mode_name);
|
|
device_destroy(tape_class, tcd->char_device->dev);
|
|
cdev_del(tcd->char_device);
|
|
kfree(tcd);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(unregister_tape_dev);
|
|
|
|
|
|
static int __init tape_init(void)
|
|
{
|
|
tape_class = class_create(THIS_MODULE, "tape390");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void __exit tape_exit(void)
|
|
{
|
|
class_destroy(tape_class);
|
|
tape_class = NULL;
|
|
}
|
|
|
|
postcore_initcall(tape_init);
|
|
module_exit(tape_exit);
|