OMAP: DSS2: string parsing cleanups

Use strtobool and kstrto* functions when parsing sysfs inputs.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
diff --git a/drivers/video/omap2/dss/display.c b/drivers/video/omap2/dss/display.c
index 94495e4..2c6e2bc 100644
--- a/drivers/video/omap2/dss/display.c
+++ b/drivers/video/omap2/dss/display.c
@@ -45,14 +45,13 @@
 		const char *buf, size_t size)
 {
 	struct omap_dss_device *dssdev = to_dss_device(dev);
-	int r, enabled;
+	int r;
+	bool enabled;
 
-	r = kstrtoint(buf, 0, &enabled);
+	r = strtobool(buf, &enabled);
 	if (r)
 		return r;
 
-	enabled = !!enabled;
-
 	if (enabled != (dssdev->state != OMAP_DSS_DISPLAY_DISABLED)) {
 		if (enabled) {
 			r = dssdev->driver->enable(dssdev);
@@ -79,17 +78,16 @@
 		struct device_attribute *attr, const char *buf, size_t size)
 {
 	struct omap_dss_device *dssdev = to_dss_device(dev);
-	int te, r;
+	int r;
+	bool te;
 
 	if (!dssdev->driver->enable_te || !dssdev->driver->get_te)
 		return -ENOENT;
 
-	r = kstrtoint(buf, 0, &te);
+	r = strtobool(buf, &te);
 	if (r)
 		return r;
 
-	te = !!te;
-
 	r = dssdev->driver->enable_te(dssdev, te);
 	if (r)
 		return r;
@@ -195,17 +193,16 @@
 		struct device_attribute *attr, const char *buf, size_t size)
 {
 	struct omap_dss_device *dssdev = to_dss_device(dev);
-	int mirror, r;
+	int r;
+	bool mirror;
 
 	if (!dssdev->driver->set_mirror || !dssdev->driver->get_mirror)
 		return -ENOENT;
 
-	r = kstrtoint(buf, 0, &mirror);
+	r = strtobool(buf, &mirror);
 	if (r)
 		return r;
 
-	mirror = !!mirror;
-
 	r = dssdev->driver->set_mirror(dssdev, mirror);
 	if (r)
 		return r;