path: root/Documentation
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authorAlan Cox <alan@linux.intel.com>2012-05-10 21:48:59 +0200
committerWim Van Sebroeck <wim@iguana.be>2012-05-30 07:54:25 +0200
commit45f5fed30a6460ec58f159ff297a2974153a97de (patch)
treed173b2d22ed1187fb7ed2cb85015ddf5c545da05 /Documentation
parentwatchdog: watchdog_core.h: make functions extern (diff)
watchdog: Add multiple device support
We keep the old /dev/watchdog interface file for the first watchdog via miscdev. This is basically a cut and paste of the relevant interface code from the rtc driver layer tweaked for watchdog. Revised to fix problems noted by Hans de Goede Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Diffstat (limited to 'Documentation')
1 files changed, 9 insertions, 1 deletions
diff --git a/Documentation/watchdog/watchdog-kernel-api.txt b/Documentation/watchdog/watchdog-kernel-api.txt
index 25fe4304f2fc..3c85fc7dc1f1 100644
--- a/Documentation/watchdog/watchdog-kernel-api.txt
+++ b/Documentation/watchdog/watchdog-kernel-api.txt
@@ -1,6 +1,6 @@
The Linux WatchDog Timer Driver Core kernel API.
-Last reviewed: 16-Mar-2012
+Last reviewed: 21-May-2012
Wim Van Sebroeck <wim@iguana.be>
@@ -39,6 +39,8 @@ watchdog_device structure.
The watchdog device structure looks like this:
struct watchdog_device {
+ int id;
+ struct cdev cdev;
const struct watchdog_info *info;
const struct watchdog_ops *ops;
unsigned int bootstatus;
@@ -50,6 +52,12 @@ struct watchdog_device {
It contains following fields:
+* id: set by watchdog_register_device, id 0 is special. It has both a
+ /dev/watchdog0 cdev (dynamic major, minor 0) as well as the old
+ /dev/watchdog miscdev. The id is set automatically when calling
+ watchdog_register_device.
+* cdev: cdev for the dynamic /dev/watchdog<id> device nodes. This
+ field is also populated by watchdog_register_device.
* info: a pointer to a watchdog_info structure. This structure gives some
additional information about the watchdog timer itself. (Like it's unique name)
* ops: a pointer to the list of watchdog operations that the watchdog supports.