cr50: Add physical presence state machine

This will be used as part of case closed debugging configuration.
Currently, this only adds the state machine, and a test command which
is available when CR50_DEV=1.  It also adds a new sleep mask flag for
physical presence detect, instead of oveloading FORCE_NO_DSLEEP.

The physical presence state machine supports both short (tap 5 times
in 15 seconds) and long (short, followed by 4 more taps 1-5 minutes
apart) sequences.  It will call a callback function at the end of the
sequence, so that multiple things can each request physical presence
in turn.  This will be used by ccdopen / ccdunlock / testlab commands
for CCD V1.

Eventually, CCD config will replace the unlock sequence handling in
wp.c.  But for now, we don't touch that.

See go/cr50-ccd-wp for more information.

BUG=b:62537474
BRANCH=none
TEST=manual
	Short sequence:
		pp short
		pp
		pp
		pp # See "Physical presence good"
	Timeout
		pp short
		pp # 15 sec later, get timeout error
	Long sequence:
		pp long
		pp
		pp
		pp
		(wait 2 sec)
		pp
		(wait 2 sec)
		pp # See "PP good"
	Long sequence, presses too fast:
		pp long
		pp
		pp
		pp
		pp # See "PP L too soon"
		(wait 2 sec)
		pp
		(wait 2 sec)
		pp # See "Physical presence good"
	Abort:
		pp short
		pp abort # See "Physical presence aborted"

Change-Id: I09da81ad11d328e7d7740c3fe838a5f67d7b8708
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/568796
Reviewed-by: Aseda Aboagye <aaboagye@chromium.org>
Reviewed-by: Vadim Bendebury <vbendeb@chromium.org>
Reviewed-by: Mary Ruthven <mruthven@chromium.org>

2 files changed, 24 insertions, 4 deletions

diff --git a/board/cr50/board.h b/board/cr50/board.h
index 9d0ebbce43..b6ebedd7b0 100644
--- a/board/cr50/board.h
+++ b/board/cr50/board.h
@@ -102,6 +102,12 @@
 
 /* Enable Case Closed Debugging */
 #define CONFIG_CASE_CLOSED_DEBUG
+#define CONFIG_PHYSICAL_PRESENCE
+
+#ifdef CR50_DEV
+/* Enable unsafe dev features for physical presence in dev builds */
+#define CONFIG_PHYSICAL_PRESENCE_DEBUG_UNSAFE
+#endif
 
 #define CONFIG_USB_PID 0x5014
 #define CONFIG_USB_SELF_POWERED
diff --git a/board/cr50/wp.c b/board/cr50/wp.c
index 3c25036647..4d074d9cbd 100644
--- a/board/cr50/wp.c
+++ b/board/cr50/wp.c
@@ -11,6 +11,7 @@
 #include "hooks.h"
 #include "nvmem.h"
 #include "nvmem_vars.h"
+#include "physical_presence.h"
 #include "registers.h"
 #include "scratch_reg1.h"
 #include "system.h"
@@ -377,7 +378,7 @@ static void unlock_sequence_is_over(void)
 	unlock_in_progress = 0;
 
 	/* Allow sleeping again */
-	enable_sleep(SLEEP_MASK_FORCE_NO_DSLEEP);
+	enable_sleep(SLEEP_MASK_PHYSICAL_PRESENCE);
 }
 DECLARE_DEFERRED(unlock_sequence_is_over);
 
@@ -397,12 +398,16 @@ static void power_button_poked(void)
 
 static void power_button_handler(void)
 {
-	if (unlock_in_progress)
+	CPRINTS("power button pressed");
+	if (physical_detect_press() == EC_SUCCESS) {
+		/* Consumed by physical detect */
+	} else if (unlock_in_progress) {
 		power_button_poked();
 #ifdef CONFIG_U2F
-	else
+	} else {
 		power_button_record();
 #endif
+	}
 
 	GWRITE_FIELD(RBOX, INT_STATE, INTR_PWRB_IN_FED, 1);
 }
@@ -420,7 +425,7 @@ static void start_unlock_process(int total_poking_time, int max_poke_interval)
 	unlock_deadline.val += total_poking_time;
 
 	/* Stay awake while we're doing this, just in case. */
-	disable_sleep(SLEEP_MASK_FORCE_NO_DSLEEP);
+	disable_sleep(SLEEP_MASK_PHYSICAL_PRESENCE);
 
 	/* Check progress after waiting long enough for one button press */
 	hook_call_deferred(&unlock_sequence_is_over_data, unlock_beat);
@@ -437,6 +442,15 @@ static void power_button_init(void)
 }
 DECLARE_HOOK(HOOK_INIT, power_button_init, HOOK_PRIO_DEFAULT);
 
+void board_physical_presence_enable(int enable)
+{
+	/* Stay awake while we're doing this, just in case. */
+	if (enable)
+		disable_sleep(SLEEP_MASK_PHYSICAL_PRESENCE);
+	else
+		enable_sleep(SLEEP_MASK_PHYSICAL_PRESENCE);
+}
+
 /****************************************************************************/
 /* TPM vendor-specific commands */