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,
 };