[PATCH] add sysfs support for ide tape

I was recently given an old Travan tape drive and asked to do something
useful with it.  The ide-scsi + st (+serverworks ide controller) combo
results in a hard lockup of the machine which I have not had the energy to
debug, so I turned to ide-tape (which seems to work).  The system in
question debian stable, using udev to manage /dev.

The following patch to ide-tape.c allows udev to create the cdev nodes for
my drive.

Cc: Gadi Oxman <gadio@netvision.net.il>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 36 insertions, 2 deletions

diff --git a/drivers/ide/ide-tape.c b/drivers/ide/ide-tape.c
index ee38e6b143a4..95abe981530d 100644
--- a/drivers/ide/ide-tape.c
+++ b/drivers/ide/ide-tape.c
@@ -1013,6 +1013,8 @@ typedef struct ide_tape_obj {
 
 static DECLARE_MUTEX(idetape_ref_sem);
 
+static struct class *idetape_sysfs_class;
+
 #define to_ide_tape(obj) container_of(obj, struct ide_tape_obj, kref)
 
 #define ide_tape_g(disk) \
@@ -4704,6 +4706,10 @@ static void ide_tape_release(struct kref *kref)
 
         drive->dsc_overlap = 0;
         drive->driver_data = NULL;
+        class_device_destroy(idetape_sysfs_class,
+                        MKDEV(IDETAPE_MAJOR, tape->minor));
+        class_device_destroy(idetape_sysfs_class,
+                        MKDEV(IDETAPE_MAJOR, tape->minor + 128));
         devfs_remove("%s/mt", drive->devfs_name);
         devfs_remove("%s/mtn", drive->devfs_name);
         devfs_unregister_tape(g->number);
@@ -4878,6 +4884,11 @@ static int ide_tape_probe(struct device *dev)
 
         idetape_setup(drive, tape, minor);
 
+        class_device_create(idetape_sysfs_class,
+                        MKDEV(IDETAPE_MAJOR, minor), dev, "%s", tape->name);
+        class_device_create(idetape_sysfs_class,
+                        MKDEV(IDETAPE_MAJOR, minor + 128), dev, "n%s", tape->name);
+
         devfs_mk_cdev(MKDEV(HWIF(drive)->major, minor),
                         S_IFCHR | S_IRUGO | S_IWUGO,
                         "%s/mt", drive->devfs_name);
@@ -4903,6 +4914,7 @@ MODULE_LICENSE("GPL");
 static void __exit idetape_exit (void)
 {
         driver_unregister(&idetape_driver.gen_driver);
+        class_destroy(idetape_sysfs_class);
         unregister_chrdev(IDETAPE_MAJOR, "ht");
 }
 
@@ -4911,11 +4923,33 @@ static void __exit idetape_exit (void)
  */
 static int idetape_init (void)
 {
+        int error = 1;
+        idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape");
+        if (IS_ERR(idetape_sysfs_class)) {
+                idetape_sysfs_class = NULL;
+                printk(KERN_ERR "Unable to create sysfs class for ide tapes\n");
+                error = -EBUSY;
+                goto out;
+        }
+
         if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) {
                 printk(KERN_ERR "ide-tape: Failed to register character device interface\n");
-                return -EBUSY;
+                error = -EBUSY;
+                goto out_free_class;
         }
-        return driver_register(&idetape_driver.gen_driver);
+
+        error = driver_register(&idetape_driver.gen_driver);
+        if (error)
+                goto out_free_driver;
+
+        return 0;
+
+out_free_driver:
+        driver_unregister(&idetape_driver.gen_driver);
+out_free_class:
+        class_destroy(idetape_sysfs_class);
+out:
+        return error;
 }
 
 module_init(idetape_init);