HID: uhid: allocate static minor

udev has this nice feature of creating "dead" /dev/<node> device-nodes if
it finds a devnode:<node> modalias. Once the node is accessed, the kernel
automatically loads the module that provides the node. However, this
requires udev to know the major:minor code to use for the node. This
feature was introduced by:

  commit 578454ff7e
  Author: Kay Sievers <kay.sievers@vrfy.org>
  Date:   Thu May 20 18:07:20 2010 +0200

      driver core: add devname module aliases to allow module on-demand auto-loading

However, uhid uses dynamic minor numbers so this doesn't actually work. We
need to load uhid to know which minor it's going to use.

Hence, allocate a static minor (just like uinput does) and we're good
to go.

Reported-by: Tom Gundersen <teg@jklm.no>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This commit is contained in:
David Herrmann 2013-09-09 18:33:54 +02:00 committed by Jiri Kosina
parent 84fca9f38c
commit 19872d20c8
2 changed files with 3 additions and 1 deletions

View File

@ -615,7 +615,7 @@ static const struct file_operations uhid_fops = {
static struct miscdevice uhid_misc = {
.fops = &uhid_fops,
.minor = MISC_DYNAMIC_MINOR,
.minor = UHID_MINOR,
.name = UHID_NAME,
};
@ -634,4 +634,5 @@ module_exit(uhid_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("David Herrmann <dh.herrmann@gmail.com>");
MODULE_DESCRIPTION("User-space I/O driver support for HID subsystem");
MODULE_ALIAS_MISCDEV(UHID_MINOR);
MODULE_ALIAS("devname:" UHID_NAME);

View File

@ -45,6 +45,7 @@
#define MAPPER_CTRL_MINOR 236
#define LOOP_CTRL_MINOR 237
#define VHOST_NET_MINOR 238
#define UHID_MINOR 239
#define MISC_DYNAMIC_MINOR 255
struct device;