Input: keyboard - add locking around event handling

Keyboard input handler is multiplexing events form all keyboard-like
devices in the system. Because of that per-device lock provided by
input core is not enough to prevent clashes in ked_event() and we
need our own lock to ensure that only one thread at a time executing
kbd_event().

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
This commit is contained in:
Dmitry Torokhov 2009-11-29 23:40:58 -08:00
parent dbe1420b4b
commit 21cea58e49

View File

@ -132,6 +132,7 @@ int shift_state = 0;
*/
static struct input_handler kbd_handler;
static DEFINE_SPINLOCK(kbd_event_lock);
static unsigned long key_down[BITS_TO_LONGS(KEY_CNT)]; /* keyboard key bitmap */
static unsigned char shift_down[NR_SHIFT]; /* shift state counters.. */
static int dead_key_next;
@ -1296,10 +1297,16 @@ static void kbd_keycode(unsigned int keycode, int down, int hw_raw)
static void kbd_event(struct input_handle *handle, unsigned int event_type,
unsigned int event_code, int value)
{
/* We are called with interrupts disabled, just take the lock */
spin_lock(&kbd_event_lock);
if (event_type == EV_MSC && event_code == MSC_RAW && HW_RAW(handle->dev))
kbd_rawcode(value);
if (event_type == EV_KEY)
kbd_keycode(event_code, value, HW_RAW(handle->dev));
spin_unlock(&kbd_event_lock);
tasklet_schedule(&keyboard_tasklet);
do_poke_blanked_console = 1;
schedule_console_callback();