Remove "Sticky" recovery mode on Daisy

Previously, if you used Esc + Reload + Power to reboot into recovery
mode, you would be stuck in it until you manually rebooted the EC with
"Reload + Power."  This was because the button combo set a switch that
was never un-set.  To fix it, the keyboard_scan function now sets a host
event, that is serviced once, and then cleared.  As a result, the next
time you reboot after triggering recovery mode, it should boot as before
you triggered recovery mode.

BUG=chrome-os-partner:10889
TEST=Boot device in normal mode.  Press Esc + Reload + Power, and boot
from usb.  Power off the device and remove the usb media.  Power on the
device again, and there should be no recovery screens during the boot
process.  Next, repeat these same steps, but from starting in developer
mode.  After recovery, when you reboot, the device should return to
developer mode.

Change-Id: Idcb8dde6f8ba5f680f4d34e61ae0d12992281cbb
Signed-off-by: Charlie Mooney <charliemooney@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/28710
Reviewed-by: Randall Spangler <rspangler@chromium.org>

1 files changed, 4 insertions, 7 deletions

diff --git a/chip/stm32/keyboard_scan.c b/chip/stm32/keyboard_scan.c
index b7cad467c4..350439ef1e 100644
--- a/chip/stm32/keyboard_scan.c
+++ b/chip/stm32/keyboard_scan.c
@@ -44,9 +44,6 @@ static struct mutex scanning_enabled;
 /* The keyboard state from the last read */
 static uint8_t raw_state[KB_OUTPUTS];
 
-/* status of keyboard related switches */
-static uint8_t switches;
-
 /* Mask with 1 bits only for keys that actually exist */
 static const uint8_t *actual_key_mask;
 
@@ -356,8 +353,7 @@ int keyboard_scan_init(void)
 	check_keys_changed();
 
 	/* is recovery key pressed on cold startup ? */
-	switches |= check_recovery_key() ?
-			EC_SWITCH_KEYBOARD_RECOVERY : 0;
+	check_recovery_key();
 
 	return EC_SUCCESS;
 }
@@ -432,7 +428,8 @@ void keyboard_put_char(uint8_t chr, int send_irq)
 
 int keyboard_scan_recovery_pressed(void)
 {
-	return switches & EC_SWITCH_KEYBOARD_RECOVERY;
+	return host_get_events() &
+	EC_HOST_EVENT_MASK(EC_HOST_EVENT_KEYBOARD_RECOVERY);
 }
 
 static int keyboard_get_scan(struct host_cmd_handler_args *args)
@@ -455,7 +452,7 @@ static int keyboard_get_info(struct host_cmd_handler_args *args)
 
 	r->rows = 8;
 	r->cols = KB_OUTPUTS;
-	r->switches = switches;
+	r->switches = 0;
 
 	args->response_size = sizeof(*r);