diff --git a/clients/clickdot.c b/clients/clickdot.c
index 3b7210e3b..1930dfe6e 100644
--- a/clients/clickdot.c
+++ b/clients/clickdot.c
@@ -110,7 +110,7 @@ key_handler(struct window *window, struct input *input, uint32_t time,
 static void
 button_handler(struct widget *widget,
 	       struct input *input, uint32_t time,
-	       int button, int state, void *data)
+	       int button, uint32_t state, void *data)
 {
 	struct clickdot *clickdot = data;
 
diff --git a/clients/desktop-shell.c b/clients/desktop-shell.c
index df4494ed9..0a6341a19 100644
--- a/clients/desktop-shell.c
+++ b/clients/desktop-shell.c
@@ -256,7 +256,7 @@ panel_launcher_leave_handler(struct widget *widget,
 static void
 panel_launcher_button_handler(struct widget *widget,
 			      struct input *input, uint32_t time,
-			      int button, int state, void *data)
+			      int button, uint32_t state, void *data)
 {
 	struct panel_launcher *launcher;
 
@@ -269,7 +269,7 @@ panel_launcher_button_handler(struct widget *widget,
 static void
 panel_button_handler(struct widget *widget,
 		     struct input *input, uint32_t time,
-		     int button, int state, void *data)
+		     int button, uint32_t state, void *data)
 {
 	struct panel *panel = data;
 
@@ -481,7 +481,7 @@ unlock_dialog_redraw_handler(struct widget *widget, void *data)
 static void
 unlock_dialog_button_handler(struct widget *widget,
 			     struct input *input, uint32_t time,
-			     int button, int state, void *data)
+			     int button, uint32_t state, void *data)
 {
 	struct unlock_dialog *dialog = data;
 	struct desktop *desktop = dialog->desktop;
diff --git a/clients/dnd.c b/clients/dnd.c
index a7ac66faf..1d1f592df 100644
--- a/clients/dnd.c
+++ b/clients/dnd.c
@@ -361,7 +361,7 @@ create_drag_cursor(struct dnd_drag *dnd_drag,
 static void
 dnd_button_handler(struct widget *widget,
 		   struct input *input, uint32_t time,
-		   int button, int state, void *data)
+		   int button, uint32_t state, void *data)
 {
 	struct dnd *dnd = data;
 	int32_t x, y;
diff --git a/clients/eventdemo.c b/clients/eventdemo.c
index 0848fc8ee..bda963001 100644
--- a/clients/eventdemo.c
+++ b/clients/eventdemo.c
@@ -211,7 +211,7 @@ key_handler(struct window *window, struct input *input, uint32_t time,
  */
 static void
 button_handler(struct widget *widget, struct input *input, uint32_t time,
-	       int button, int state, void *data)
+	       int button, uint32_t state, void *data)
 {
 	int32_t x, y;
 
diff --git a/clients/flower.c b/clients/flower.c
index 2d13f9e86..7e8cba758 100644
--- a/clients/flower.c
+++ b/clients/flower.c
@@ -142,7 +142,7 @@ motion_handler(struct widget *widget, struct input *input,
 static void
 button_handler(struct widget *widget,
 	       struct input *input, uint32_t time,
-	       int button, int state, void *data)
+	       int button, uint32_t state, void *data)
 {
 	struct flower *flower = data;
 
diff --git a/clients/gears.c b/clients/gears.c
index c432bc584..4dea8f2f4 100644
--- a/clients/gears.c
+++ b/clients/gears.c
@@ -251,7 +251,7 @@ motion_handler(struct widget *widget, struct input *input,
 
 static void
 button_handler(struct widget *widget, struct input *input,
-		uint32_t time, int button, int state, void *data)
+		uint32_t time, int button, uint32_t state, void *data)
 {
 	struct gears *gears = data;
 
diff --git a/clients/resizor.c b/clients/resizor.c
index 67d4899dc..37c400bec 100644
--- a/clients/resizor.c
+++ b/clients/resizor.c
@@ -178,7 +178,7 @@ show_menu(struct resizor *resizor, struct input *input, uint32_t time)
 static void
 button_handler(struct widget *widget,
 	       struct input *input, uint32_t time,
-	       int button, int state, void *data)
+	       int button, uint32_t state, void *data)
 {
 	struct resizor *resizor = data;
 
diff --git a/clients/tablet-shell.c b/clients/tablet-shell.c
index 4f4eec54b..9ba9701cc 100644
--- a/clients/tablet-shell.c
+++ b/clients/tablet-shell.c
@@ -217,7 +217,7 @@ lockscreen_draw(struct widget *widget, void *data)
 static void
 lockscreen_button_handler(struct widget *widget,
 			  struct input *input, uint32_t time,
-			  int button, int state, void *data)
+			  int button, uint32_t state, void *data)
 {
 	struct lockscreen *lockscreen = data;
 
diff --git a/clients/terminal.c b/clients/terminal.c
index 106e3d1db..659763fc4 100644
--- a/clients/terminal.c
+++ b/clients/terminal.c
@@ -2213,7 +2213,7 @@ keyboard_focus_handler(struct window *window,
 static void
 button_handler(struct widget *widget,
 	       struct input *input, uint32_t time,
-	       int button, int state, void *data)
+	       int button, uint32_t state, void *data)
 {
 	struct terminal *terminal = data;
 
diff --git a/clients/view.c b/clients/view.c
index 1264207f7..c17bb1234 100644
--- a/clients/view.c
+++ b/clients/view.c
@@ -138,7 +138,7 @@ view_page_down(struct view *view)
 
 static void
 button_handler(struct widget *widget, struct input *input, uint32_t time,
-               int button, int state, void *data)
+               int button, uint32_t state, void *data)
 {
         struct view *view = data;
 
diff --git a/clients/window.c b/clients/window.c
index 2dcf421fc..ce67e691b 100644
--- a/clients/window.c
+++ b/clients/window.c
@@ -1220,7 +1220,7 @@ frame_motion_handler(struct widget *widget,
 static void
 frame_button_handler(struct widget *widget,
 		     struct input *input, uint32_t time,
-		     int button, int state, void *data)
+		     int button, uint32_t state, void *data)
 
 {
 	struct frame *frame = data;
@@ -2363,7 +2363,7 @@ menu_leave_handler(struct widget *widget, struct input *input, void *data)
 static void
 menu_button_handler(struct widget *widget,
 		    struct input *input, uint32_t time,
-		    int button, int state, void *data)
+		    int button, uint32_t state, void *data)
 
 {
 	struct menu *menu = data;
diff --git a/clients/window.h b/clients/window.h
index a2a788064..d2abb3d3a 100644
--- a/clients/window.h
+++ b/clients/window.h
@@ -190,7 +190,8 @@ typedef int (*widget_motion_handler_t)(struct widget *widget,
 				       int32_t x, int32_t y, void *data);
 typedef void (*widget_button_handler_t)(struct widget *widget,
 					struct input *input, uint32_t time,
-					int button, int state, void *data);
+					int button, uint32_t state,
+					void *data);
 
 struct window *
 window_create(struct display *display);
diff --git a/src/compositor.c b/src/compositor.c
index 235b4a2bf..f5087459b 100644
--- a/src/compositor.c
+++ b/src/compositor.c
@@ -1604,7 +1604,7 @@ weston_surface_activate(struct weston_surface *surface,
 
 WL_EXPORT void
 notify_button(struct wl_input_device *device,
-	      uint32_t time, int32_t button, int32_t state)
+	      uint32_t time, int32_t button, uint32_t state)
 {
 	struct weston_input_device *wd = (struct weston_input_device *) device;
 	struct weston_compositor *compositor = wd->compositor;
diff --git a/src/compositor.h b/src/compositor.h
index 3722d32f5..fac07c787 100644
--- a/src/compositor.h
+++ b/src/compositor.h
@@ -416,7 +416,7 @@ notify_motion(struct wl_input_device *device,
 	      uint32_t time, int x, int y);
 void
 notify_button(struct wl_input_device *device,
-	      uint32_t time, int32_t button, int32_t state);
+	      uint32_t time, int32_t button, uint32_t state);
 void
 notify_axis(struct wl_input_device *device,
 	      uint32_t time, uint32_t axis, int32_t value);
diff --git a/src/shell.c b/src/shell.c
index 8c35ae899..738f6c8d5 100644
--- a/src/shell.c
+++ b/src/shell.c
@@ -327,7 +327,7 @@ move_grab_motion(struct wl_pointer_grab *grab,
 
 static void
 move_grab_button(struct wl_pointer_grab *grab,
-		 uint32_t time, uint32_t button, int32_t state)
+		 uint32_t time, uint32_t button, uint32_t state)
 {
 	struct shell_grab *shell_grab = container_of(grab, struct shell_grab,
 						    grab);
@@ -587,7 +587,7 @@ resize_grab_motion(struct wl_pointer_grab *grab,
 
 static void
 resize_grab_button(struct wl_pointer_grab *grab,
-		   uint32_t time, uint32_t button, int32_t state)
+		   uint32_t time, uint32_t button, uint32_t state)
 {
 	struct weston_resize_grab *resize = (struct weston_resize_grab *) grab;
 	struct wl_input_device *device = grab->input_device;
@@ -1062,7 +1062,7 @@ popup_grab_motion(struct wl_pointer_grab *grab,
 
 static void
 popup_grab_button(struct wl_pointer_grab *grab,
-		  uint32_t time, uint32_t button, int32_t state)
+		  uint32_t time, uint32_t button, uint32_t state)
 {
 	struct wl_resource *resource;
 	struct shell_surface *shsurf =
@@ -1711,7 +1711,7 @@ rotate_grab_motion(struct wl_pointer_grab *grab,
 
 static void
 rotate_grab_button(struct wl_pointer_grab *grab,
-		 uint32_t time, uint32_t button, int32_t state)
+		 uint32_t time, uint32_t button, uint32_t state)
 {
 	struct rotate_grab *rotate =
 		container_of(grab, struct rotate_grab, base.grab);
@@ -2403,7 +2403,7 @@ switcher_destroy(struct switcher *switcher, uint32_t time)
 
 static void
 switcher_key(struct wl_keyboard_grab *grab,
-	     uint32_t time, uint32_t key, int32_t state)
+	     uint32_t time, uint32_t key, uint32_t state)
 {
 	struct switcher *switcher = container_of(grab, struct switcher, grab);
 	struct weston_input_device *device =
diff --git a/src/util.c b/src/util.c
index 99438202e..78f698016 100644
--- a/src/util.c
+++ b/src/util.c
@@ -249,7 +249,7 @@ struct binding_keyboard_grab {
 
 static void
 binding_key(struct wl_keyboard_grab *grab,
-	    uint32_t time, uint32_t key, int32_t state)
+	    uint32_t time, uint32_t key, uint32_t state)
 {
 	struct binding_keyboard_grab *b =
 		container_of(grab, struct binding_keyboard_grab, grab);