HID: fix incorrect handling of devices with high button count

Button names for USB gamepads are currently assigned incorrectly, as the evdev
code assigned to buttons is "BTN_GAMEPAD + code", which on devices with more
then 16 buttons bleeds over into button names reserved for graphic tablets
(BTN_TOOL_PEN, etc.). This causes problems further down the line as the device
are now no longer detected as joystick. This patch fixes that by assigning
buttons outside the range to BTN_TRIGGER_HAPPY (as is already the case for USB
joysticks).

Furthermore this patch corrects the assignment to BTN_TRIGGER_HAPPY, as
currently the first button over 16 is assigned to BTN_TRIGGER_HAPPY17 (i.e.
BTN_TRIGGER_HAPPY+0x10) not BTN_TRIGGER_HAPPY.

Signed-off-by: Ingo Ruhnke <grumbel@gmail.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

1 files changed, 7 insertions, 2 deletions

diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
index d917c0d53685..10248cf548fc 100644
--- a/drivers/hid/hid-input.c
+++ b/drivers/hid/hid-input.c
@@ -502,9 +502,14 @@ static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_fiel
                                 if (code <= 0xf)
                                         code += BTN_JOYSTICK;
                                 else
-                                        code += BTN_TRIGGER_HAPPY;
+                                        code += BTN_TRIGGER_HAPPY - 0x10;
+                                break;
+                case HID_GD_GAMEPAD:
+                                if (code <= 0xf)
+                                        code += BTN_GAMEPAD;
+                                else
+                                        code += BTN_TRIGGER_HAPPY - 0x10;
                                 break;
-                case HID_GD_GAMEPAD:  code += BTN_GAMEPAD; break;
                 default:
                         switch (field->physical) {
                         case HID_GD_MOUSE: