blob: 0a5702981f1d2d10fbf3d428c7a16bb9ca28b464 [file] [log] [blame]
/* Copyright 2017 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
/* Recovery button override module. */
#include "common.h"
#include "console.h"
#include "extension.h"
#include "registers.h"
#include "system.h"
#include "timer.h"
#include "u2f_impl.h"
#include "util.h"
/*
* The recovery button, on some systems only, is wired to KEY0 in rbox. For
* testing, we need to be able override the value. We'll have a vendor command
* such that the AP can query the state of the recovery button. However, the
* reported state can only be overridden with a console command given sufficient
* privileges.
*/
static uint8_t rec_btn_force_pressed;
/*
* Timestamp of the most recent recovery button press
*/
static timestamp_t last_press;
/* How long do we latch the last recovery button press */
#define RECOVERY_BUTTON_TIMEOUT (10 * SECOND)
void recovery_button_record(void)
{
last_press = get_time();
/*
* Pressing the power button causes the AP to shutdown, and typically
* the Cr50 will enter deep sleep very quickly. Delay deep sleep
* so the recovery button state is saved long enough for the AP to
* power on and read the recovery button state.
*/
delay_sleep_by(RECOVERY_BUTTON_TIMEOUT);
}
/*
* Read the recovery button latched state and unconditionally clear the state.
*
* Returns 1 iff the recovery button key combination was recorded within the
* last RECOVERY_BUTTON_TIMEOUT microseconds. Note that deep sleep also
* clears the recovery button state.
*/
static int pop_recovery_button_state(void)
{
int latched_state = 0;
if (last_press.val &&
((get_time().val - last_press.val) < RECOVERY_BUTTON_TIMEOUT))
latched_state = 1;
last_press.val = 0;
/* Latched recovery button state */
return latched_state;
}
static uint8_t is_rec_btn_pressed(void)
{
if (rec_btn_force_pressed)
return 1;
/*
* Platform has a defined recovery button combination and it
* the combination was pressed within a timeout
*/
if (board_uses_closed_source_set1() && pop_recovery_button_state())
return 1;
/*
* If not force pressed, check the actual state of button. Note,
* the value is inverted because the button is active low.
*/
return !GREAD_FIELD(RBOX, CHECK_INPUT, KEY0_IN);
}
static int command_recbtnforce(int argc, char **argv)
{
int val;
if (argc > 2)
return EC_ERROR_PARAM_COUNT;
if (argc == 2) {
/* Make sure we're allowed to override the recovery button. */
if (console_is_restricted())
return EC_ERROR_ACCESS_DENIED;
if (!parse_bool(argv[1], &val))
return EC_ERROR_PARAM1;
rec_btn_force_pressed = val;
}
ccprintf("RecBtn: %s pressed\n",
rec_btn_force_pressed ? "forced" :
is_rec_btn_pressed() ? "" : "not");
return EC_SUCCESS;
}
DECLARE_SAFE_CONSOLE_COMMAND(recbtnforce, command_recbtnforce,
"[enable | disable]",
"Force enable the reported recbtn state.");
static enum vendor_cmd_rc vc_get_rec_btn(enum vendor_cmd_cc code,
void *buf,
size_t input_size,
size_t *response_size)
{
*(uint8_t *)buf = is_rec_btn_pressed();
*response_size = 1;
ccprints("%s: state=%d", __func__, *(uint8_t *)buf);
return VENDOR_RC_SUCCESS;
}
DECLARE_VENDOR_COMMAND(VENDOR_CC_GET_REC_BTN, vc_get_rec_btn);