]> git.karo-electronics.de Git - karo-tx-linux.git/blob - drivers/s390/char/tape_class.c
Merge tag 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
[karo-tx-linux.git] / drivers / s390 / char / tape_class.c
1 /*
2  * Copyright IBM Corp. 2004
3  *
4  * Tape class device support
5  *
6  * Author: Stefan Bader <shbader@de.ibm.com>
7  * Based on simple class device code by Greg K-H
8  */
9
10 #define KMSG_COMPONENT "tape"
11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12
13 #include <linux/slab.h>
14
15 #include "tape_class.h"
16
17 MODULE_AUTHOR("Stefan Bader <shbader@de.ibm.com>");
18 MODULE_DESCRIPTION(
19         "Copyright IBM Corp. 2004   All Rights Reserved.\n"
20         "tape_class.c"
21 );
22 MODULE_LICENSE("GPL");
23
24 static struct class *tape_class;
25
26 /*
27  * Register a tape device and return a pointer to the cdev structure.
28  *
29  * device
30  *      The pointer to the struct device of the physical (base) device.
31  * drivername
32  *      The pointer to the drivers name for it's character devices.
33  * dev
34  *      The intended major/minor number. The major number may be 0 to
35  *      get a dynamic major number.
36  * fops
37  *      The pointer to the drivers file operations for the tape device.
38  * devname
39  *      The pointer to the name of the character device.
40  */
41 struct tape_class_device *register_tape_dev(
42         struct device *         device,
43         dev_t                   dev,
44         const struct file_operations *fops,
45         char *                  device_name,
46         char *                  mode_name)
47 {
48         struct tape_class_device *      tcd;
49         int             rc;
50         char *          s;
51
52         tcd = kzalloc(sizeof(struct tape_class_device), GFP_KERNEL);
53         if (!tcd)
54                 return ERR_PTR(-ENOMEM);
55
56         strncpy(tcd->device_name, device_name, TAPECLASS_NAME_LEN);
57         for (s = strchr(tcd->device_name, '/'); s; s = strchr(s, '/'))
58                 *s = '!';
59         strncpy(tcd->mode_name, mode_name, TAPECLASS_NAME_LEN);
60         for (s = strchr(tcd->mode_name, '/'); s; s = strchr(s, '/'))
61                 *s = '!';
62
63         tcd->char_device = cdev_alloc();
64         if (!tcd->char_device) {
65                 rc = -ENOMEM;
66                 goto fail_with_tcd;
67         }
68
69         tcd->char_device->owner = fops->owner;
70         tcd->char_device->ops   = fops;
71         tcd->char_device->dev   = dev;
72
73         rc = cdev_add(tcd->char_device, tcd->char_device->dev, 1);
74         if (rc)
75                 goto fail_with_cdev;
76
77         tcd->class_device = device_create(tape_class, device,
78                                           tcd->char_device->dev, NULL,
79                                           "%s", tcd->device_name);
80         rc = IS_ERR(tcd->class_device) ? PTR_ERR(tcd->class_device) : 0;
81         if (rc)
82                 goto fail_with_cdev;
83         rc = sysfs_create_link(
84                 &device->kobj,
85                 &tcd->class_device->kobj,
86                 tcd->mode_name
87         );
88         if (rc)
89                 goto fail_with_class_device;
90
91         return tcd;
92
93 fail_with_class_device:
94         device_destroy(tape_class, tcd->char_device->dev);
95
96 fail_with_cdev:
97         cdev_del(tcd->char_device);
98
99 fail_with_tcd:
100         kfree(tcd);
101
102         return ERR_PTR(rc);
103 }
104 EXPORT_SYMBOL(register_tape_dev);
105
106 void unregister_tape_dev(struct device *device, struct tape_class_device *tcd)
107 {
108         if (tcd != NULL && !IS_ERR(tcd)) {
109                 sysfs_remove_link(&device->kobj, tcd->mode_name);
110                 device_destroy(tape_class, tcd->char_device->dev);
111                 cdev_del(tcd->char_device);
112                 kfree(tcd);
113         }
114 }
115 EXPORT_SYMBOL(unregister_tape_dev);
116
117
118 static int __init tape_init(void)
119 {
120         tape_class = class_create(THIS_MODULE, "tape390");
121
122         return 0;
123 }
124
125 static void __exit tape_exit(void)
126 {
127         class_destroy(tape_class);
128         tape_class = NULL;
129 }
130
131 postcore_initcall(tape_init);
132 module_exit(tape_exit);