watchdog: WatchDog Timer Driver Core - Add basic ioctl functionality

This part add's the basic ioctl functionality to the
WatchDog Timer Driver Core framework. The supported
ioctl call's are:
	WDIOC_GETSUPPORT
	WDIOC_GETSTATUS
	WDIOC_GETBOOTSTATUS

Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>

1 files changed, 32 insertions, 0 deletions

diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
index 366f49ce69b8..00a611293065 100644
--- a/drivers/watchdog/watchdog_dev.c
+++ b/drivers/watchdog/watchdog_dev.c
@@ -95,6 +95,37 @@ static ssize_t watchdog_write(struct file *file, const char __user *data,
 }
 
 /*
+ *      watchdog_ioctl: handle the different ioctl's for the watchdog device.
+ *      @file: file handle to the device
+ *      @cmd: watchdog command
+ *      @arg: argument pointer
+ *
+ *      The watchdog API defines a common set of functions for all watchdogs
+ *      according to their available features.
+ */
+
+static long watchdog_ioctl(struct file *file, unsigned int cmd,
+                                                        unsigned long arg)
+{
+        void __user *argp = (void __user *)arg;
+        int __user *p = argp;
+        unsigned int val;
+
+        switch (cmd) {
+        case WDIOC_GETSUPPORT:
+                return copy_to_user(argp, wdd->info,
+                        sizeof(struct watchdog_info)) ? -EFAULT : 0;
+        case WDIOC_GETSTATUS:
+                val = wdd->ops->status ? wdd->ops->status(wdd) : 0;
+                return put_user(val, p);
+        case WDIOC_GETBOOTSTATUS:
+                return put_user(wdd->bootstatus, p);
+        default:
+                return -ENOTTY;
+        }
+}
+
+/*
  *      watchdog_open: open the /dev/watchdog device.
  *      @inode: inode of device
  *      @file: file handle to device
@@ -163,6 +194,7 @@ static int watchdog_release(struct inode *inode, struct file *file)
 static const struct file_operations watchdog_fops = {
         .owner          = THIS_MODULE,
         .write          = watchdog_write,
+        .unlocked_ioctl = watchdog_ioctl,
         .open           = watchdog_open,
         .release        = watchdog_release,
 };