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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/s390/char/tape_class.c
Initial import
Diffstat (limited to 'drivers/s390/char/tape_class.c')
-rw-r--r--drivers/s390/char/tape_class.c132
1 files changed, 132 insertions, 0 deletions
diff --git a/drivers/s390/char/tape_class.c b/drivers/s390/char/tape_class.c
new file mode 100644
index 000000000..91c3c642c
--- /dev/null
+++ b/drivers/s390/char/tape_class.c
@@ -0,0 +1,132 @@
+/*
+ * 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);
+
+ strncpy(tcd->device_name, device_name, TAPECLASS_NAME_LEN);
+ for (s = strchr(tcd->device_name, '/'); s; s = strchr(s, '/'))
+ *s = '!';
+ strncpy(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;
+ tcd->char_device->dev = dev;
+
+ rc = cdev_add(tcd->char_device, 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_RET(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);