path: root/Documentation/parport-lowlevel.txt
diff options
authorMikulas Patocka <>2007-11-22 21:26:01 +0100
committerLinus Torvalds <>2007-11-26 19:39:01 -0800
commitcdb32706f6948238ed6d1d85473c64c27366e9e9 (patch)
treebc8b267a0b861bbafae9c384cf80a03e14db8bbd /Documentation/parport-lowlevel.txt
parentf6ce5cca74b8681fdf1d7307edc66a7213b43f6f (diff)
plip: fix parport_register_device name parameter
Plip passes a string "name" that is allocated on stack to parport_register_device. parport_register_device holds the pointer to "name" and when the registering function exits, it points nowhere. On some machine, this bug causes bad names to appear in /proc, such as /proc/sys/dev/parport/parport0/devices/T^/�X^/�, on others, the plip proc node is completely missing. The patch also fixes documentation to note this requirement. Signed-off-by: Mikulas Patocka <> Signed-off-by: Linus Torvalds <>
Diffstat (limited to 'Documentation/parport-lowlevel.txt')
1 files changed, 4 insertions, 0 deletions
diff --git a/Documentation/parport-lowlevel.txt b/Documentation/parport-lowlevel.txt
index 265fcdcb8e5f..120eb20dbb09 100644
--- a/Documentation/parport-lowlevel.txt
+++ b/Documentation/parport-lowlevel.txt
@@ -339,6 +339,10 @@ Use this function to register your device driver on a parallel port
('port'). Once you have done that, you will be able to use
parport_claim and parport_release in order to use the port.
+The ('name') argument is the name of the device that appears in /proc
+filesystem. The string must be valid for the whole lifetime of the
+device (until parport_unregister_device is called).
This function will register three callbacks into your driver:
'preempt', 'wakeup' and 'irq'. Each of these may be NULL in order to
indicate that you do not want a callback.