[Qemu-devel] [PATCH v2] ps2: add support for mice with extra/side buttons

[Fabian Lesniak]

This patch introduces the SIDE and EXTRA mouse buttons and implements
appropriate event generation for gtk and input-linux input methods.
The naming was borrowed from evdev since it is more descriptive than
BUTTON4/5.

Note that the guest has to switch the ps2 mouse into IMEX mode, otherwise
events of the extra buttons are ignored. For example on a Windows guest one
needs to manually select the "Microsoft PS/2 Mouse" driver.

Signed-off-by: Fabian Lesniak <fab...@lesniak-it.de>
---
 hw/input/ps2.c   | 6 ++++++
 qapi-schema.json | 7 ++++++-
 ui/gtk.c         | 4 ++++
 ui/input-linux.c | 6 ++++++
 4 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/hw/input/ps2.c b/hw/input/ps2.c
index 0d14de0..7347da5 100644
--- a/hw/input/ps2.c
+++ b/hw/input/ps2.c
@@ -870,10 +870,16 @@ static void ps2_mouse_send_packet(PS2MouseState *s)
 static void ps2_mouse_event(DeviceState *dev, QemuConsole *src,
                             InputEvent *evt)
 {
+    /* the definition of MOUSE_EVENT_WHEELUP/MOUSE_EVENT_WHEELDN
+     * is ambiguous since ps2_mouse_send_packet expects the bits
+     * for buttons 4 and 5 at s->mouse_buttons & 0x18 which
+     * matches MOUSE_EVENT_WHEELUP/MOUSE_EVENT_WHEELDN */
     static const int bmap[INPUT_BUTTON__MAX] = {
         [INPUT_BUTTON_LEFT]   = MOUSE_EVENT_LBUTTON,
         [INPUT_BUTTON_MIDDLE] = MOUSE_EVENT_MBUTTON,
         [INPUT_BUTTON_RIGHT]  = MOUSE_EVENT_RBUTTON,
+        [INPUT_BUTTON_SIDE]   = MOUSE_EVENT_WHEELUP,
+        [INPUT_BUTTON_EXTRA]  = MOUSE_EVENT_WHEELDN,
     };
     PS2MouseState *s = (PS2MouseState *)dev;
     InputMoveEvent *move;
diff --git a/qapi-schema.json b/qapi-schema.json
index f3e9bfc..7f3272f 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -4277,10 +4277,15 @@
 #
 # Button of a pointer input device (mouse, tablet).
 #
+# @side: front side button of a 5-button mouse (since 2.9)
+#
+# @extra: rear side button of a 5-button mouse (since 2.9)
+#
 # Since: 2.0
 ##
 { 'enum'  : 'InputButton',
-  'data'  : [ 'left', 'middle', 'right', 'wheel-up', 'wheel-down' ] }
+  'data'  : [ 'left', 'middle', 'right', 'wheel-up', 'wheel-down', 'side',
+  'extra' ] }

 ##
 # @InputAxis
diff --git a/ui/gtk.c b/ui/gtk.c
index e816428..9cdce83 100644
--- a/ui/gtk.c
+++ b/ui/gtk.c
@@ -995,6 +995,10 @@ static gboolean gd_button_event(GtkWidget *widget, 
GdkEventButton *button,
         btn = INPUT_BUTTON_MIDDLE;
     } else if (button->button == 3) {
         btn = INPUT_BUTTON_RIGHT;
+    } else if (button->button == 8) {
+        btn = INPUT_BUTTON_SIDE;
+    } else if (button->button == 9) {
+        btn = INPUT_BUTTON_EXTRA;
     } else {
         return TRUE;
     }
diff --git a/ui/input-linux.c b/ui/input-linux.c
index f345317..ac31f47 100644
--- a/ui/input-linux.c
+++ b/ui/input-linux.c
@@ -291,6 +291,12 @@ static void input_linux_handle_mouse(InputLinux 
*il, struct input_event *event)
             qemu_input_queue_btn(NULL, INPUT_BUTTON_WHEEL_DOWN,
                                  event->value);
             break;
+        case BTN_SIDE:
+            qemu_input_queue_btn(NULL, INPUT_BUTTON_SIDE, event->value);
+            break;
+        case BTN_EXTRA:
+            qemu_input_queue_btn(NULL, INPUT_BUTTON_EXTRA, event->value);
+            break;
         };
         break;
     case EV_REL:
--
2.10.2