Add AP hang detection

BUG=chrome-os-partner:24558
BRANCH=none
TEST=see procedure in bug

Change-Id: I42614a1da5f24c93b6267d81339ff9d721bf0d8f
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/180080
Reviewed-by: Bill Richardson <wfrichar@chromium.org>

include/ap_hang_detect.h

@@ -0,0 +1,20 @@
+/* Copyright (c) 2013 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.
+ */
+
+/* Power button API for Chrome EC */
+
+#ifndef __CROS_EC_AP_HANG_DETECT_H
+#define __CROS_EC_AP_HANG_DETECT_H
+
+#include "common.h"
+
+/**
+ * If the hang detect timers were started and can be stopped by any host
+ * command, stop them.  This is intended to be called by the the host command
+ * module.
+ */
+void hang_detect_stop_on_host_command(void);
+
+#endif  /* __CROS_EC_AP_HANG_DETECT_H */

include/config.h

@@ -52,6 +52,9 @@
 #undef CONFIG_ALS
 #undef CONFIG_ALS_ISL29035
 
+/* Support AP hang detection host command and state machine */
+#undef CONFIG_AP_HANG_DETECT
+
 /*
  * Support controlling the display backlight based on the state of the lid
  * switch.  The EC will disable the backlight when the lid is closed.

include/ec_commands.h

@@ -249,6 +249,11 @@ enum host_event_code {
 	/* Suggest that the AP resume normal speed */
 	EC_HOST_EVENT_THROTTLE_STOP = 19,
 
+	/* Hang detect logic detected a hang and host event timeout expired */
+	EC_HOST_EVENT_HANG_DETECT = 20,
+	/* Hang detect logic detected a hang and warm rebooted the AP */
+	EC_HOST_EVENT_HANG_REBOOT = 21,
+
 	/*
 	 * The high bit of the event mask is not used as a host event code.  If
 	 * it reads back as set, then the entire event mask should be
@@ -1707,6 +1712,60 @@ struct ec_response_i2c_passthru {
 	uint8_t data[];		/* Data read by messages concatenated here */
 } __packed;
 
+/*****************************************************************************/
+/* Power button hang detect */
+
+#define EC_CMD_HANG_DETECT 0x9f
+
+/* Reasons to start hang detection timer */
+/* Power button pressed */
+#define EC_HANG_START_ON_POWER_PRESS  (1 << 0)
+
+/* Lid closed */
+#define EC_HANG_START_ON_LID_CLOSE    (1 << 1)
+
+ /* Lid opened */
+#define EC_HANG_START_ON_LID_OPEN     (1 << 2)
+
+/* Start of AP S3->S0 transition (booting or resuming from suspend) */
+#define EC_HANG_START_ON_RESUME       (1 << 3)
+
+/* Reasons to cancel hang detection */
+
+/* Power button released */
+#define EC_HANG_STOP_ON_POWER_RELEASE (1 << 8)
+
+/* Any host command from AP received */
+#define EC_HANG_STOP_ON_HOST_COMMAND  (1 << 9)
+
+/* Stop on end of AP S0->S3 transition (suspending or shutting down) */
+#define EC_HANG_STOP_ON_SUSPEND       (1 << 10)
+
+/*
+ * If this flag is set, all the other fields are ignored, and the hang detect
+ * timer is started.  This provides the AP a way to start the hang timer
+ * without reconfiguring any of the other hang detect settings.  Note that
+ * you must previously have configured the timeouts.
+ */
+#define EC_HANG_START_NOW             (1 << 30)
+
+/*
+ * If this flag is set, all the other fields are ignored (including
+ * EC_HANG_START_NOW).  This provides the AP a way to stop the hang timer
+ * without reconfiguring any of the other hang detect settings.
+ */
+#define EC_HANG_STOP_NOW              (1 << 31)
+
+struct ec_params_hang_detect {
+	/* Flags; see EC_HANG_* */
+	uint32_t flags;
+
+	/* Timeout in msec before generating host event, if enabled */
+	uint16_t host_event_timeout_msec;
+
+	/* Timeout in msec before generating warm reboot, if enabled */
+	uint16_t warm_reboot_timeout_msec;
+} __packed;
 
 /*****************************************************************************/
 /* Debug commands for battery charging */