Input: adbhid - fix capslock key state after suspend

If the adbhid module parameter restore_capslock_events is used,
sometimes capslock will get stuck down after resuming.

My fix is to remember the capslock state before suspend and then
ignore the first 'caps lock key down' message after resume if the
capslock LED was on before suspending.

Signed-off-by: Rodney Lorrimar <rodney@rodney.id.au>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

diff --git a/drivers/macintosh/adbhid.c b/drivers/macintosh/adbhid.c
index ef4c117ea35fde801a43eeea0d1dbf8aebc14190..6e9afe26db893dfdb98be43961177d43fbd96ae4 100644 (file)
--- a/drivers/macintosh/adbhid.c
+++ b/drivers/macintosh/adbhid.c
@@ -219,11 +219,12 @@ struct adbhid {
        int flags;
 };
 
-#define FLAG_FN_KEY_PRESSED    0x00000001
-#define FLAG_POWER_FROM_FN     0x00000002
-#define FLAG_EMU_FWDEL_DOWN    0x00000004
-#define FLAG_CAPSLOCK_TRANSLATE        0x00000008
-#define FLAG_CAPSLOCK_DOWN     0x00000010
+#define FLAG_FN_KEY_PRESSED            0x00000001
+#define FLAG_POWER_FROM_FN             0x00000002
+#define FLAG_EMU_FWDEL_DOWN            0x00000004
+#define FLAG_CAPSLOCK_TRANSLATE                0x00000008
+#define FLAG_CAPSLOCK_DOWN             0x00000010
+#define FLAG_CAPSLOCK_IGNORE_NEXT      0x00000020
 
 static struct adbhid *adbhid[16];
 
@@ -291,8 +292,15 @@ adbhid_input_keycode(int id, int scancode, int repeat)
                if (keycode == ADB_KEY_CAPSLOCK && !up_flag) {
                        /* Key pressed, turning on the CapsLock LED.
                         * The next 0xff will be interpreted as a release. */
-                       ahid->flags |= FLAG_CAPSLOCK_TRANSLATE
+                       if (ahid->flags & FLAG_CAPSLOCK_IGNORE_NEXT) {
+                               /* Throw away this key event if it happens
+                                * just after resume. */
+                               ahid->flags &= ~FLAG_CAPSLOCK_IGNORE_NEXT;
+                               return;
+                       } else {
+                               ahid->flags |= FLAG_CAPSLOCK_TRANSLATE
                                        | FLAG_CAPSLOCK_DOWN;
+                       }
                } else if (scancode == 0xff) {
                        /* Scancode 0xff usually signifies that the capslock
                         * key was either pressed or released. */
@@ -681,6 +689,21 @@ static int adbhid_kbd_event(struct input_dev *dev, unsigned int type, unsigned i
        return -1;
 }
 
+static void
+adbhid_kbd_capslock_remember(void)
+{
+       struct adbhid *ahid;
+       int i;
+
+       for (i = 1; i < 16; i++) {
+               ahid = adbhid[i];
+
+               if (ahid && ahid->id == ADB_KEYBOARD)
+                       if (ahid->flags & FLAG_CAPSLOCK_TRANSLATE)
+                               ahid->flags |= FLAG_CAPSLOCK_IGNORE_NEXT;
+       }
+}
+
 static int
 adb_message_handler(struct notifier_block *this, unsigned long code, void *x)
 {
@@ -697,8 +720,17 @@ adb_message_handler(struct notifier_block *this, unsigned long code, void *x)
                }
 
                /* Stop pending led requests */
-               while(leds_req_pending)
+               while (leds_req_pending)
                        adb_poll();
+
+               /* After resume, and if the capslock LED is on, the PMU will
+                * send a "capslock down" key event. This confuses the
+                * restore_capslock_events logic. Remember if the capslock
+                * LED was on before suspend so the unwanted key event can
+                * be ignored after resume. */
+               if (restore_capslock_events)
+                       adbhid_kbd_capslock_remember();
+
                break;
 
        case ADB_MSG_POST_RESET: