grunt: Improve battery presence checks

Use CONFIG_BATTERY_HW_PRESENT_CUSTOM and
CONFIG_BATTERY_PRESENT_CUSTOM to make Grunt closer
to Coral and Eve.

This gets auto-power-on-with-no-battery closer
to working, because charge_prevent_power_on uses
battery_hw_present for its factory override check:

"Factory override: Always allow power on if WP is disabled,
 except when auto-power-on at EC startup and the battery
 is physically present."

BUG=b:72645441
BRANCH=none
TEST=cold reset Grunt with battery connected and disconnected

Change-Id: I2b158bedcad7dffc340992dc020145a4c6e60802
Signed-off-by: Edward Hill <ecgh@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/900048
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Duncan Laurie <dlaurie@google.com>

3 files changed, 97 insertions, 2 deletions

diff --git a/board/grunt/battery.c b/board/grunt/battery.c
index 49e943165d..d3a10e75f5 100644
--- a/board/grunt/battery.c
+++ b/board/grunt/battery.c
@@ -6,12 +6,22 @@
  */
 #include "battery.h"
 #include "battery_smart.h"
+#include "console.h"
 #include "extpower.h"
 #include "gpio.h"
+#include "hooks.h"
+#include "timer.h"
+
+#define CPRINTS(format, args...) cprints(CC_CHARGER, format, ## args)
 
 /* Shutdown mode parameter to write to manufacturer access register */
 #define SB_SHUTDOWN_DATA	0x0010
 
+static enum battery_present batt_pres_prev = BP_NOT_SURE;
+
+/* Battery may delay reporting battery present */
+static int battery_report_present = 1;
+
 static const struct battery_info info = {
 	.voltage_max = 13200, /* mV */
 	.voltage_normal = 11550,
@@ -24,10 +34,12 @@ static const struct battery_info info = {
 	.discharging_min_c = -20,
 	.discharging_max_c = 75,
 };
+
 const struct battery_info *battery_get_info(void)
 {
 	return &info;
 }
+
 int board_cut_off_battery(void)
 {
 	int rv;
@@ -37,3 +49,77 @@ int board_cut_off_battery(void)
 		return rv;
 	return sb_write(SB_MANUFACTURER_ACCESS, SB_SHUTDOWN_DATA);
 }
+
+enum battery_present battery_hw_present(void)
+{
+	/* The GPIO is low when the battery is physically present */
+	return gpio_get_level(GPIO_EC_BATT_PRES_ODL) ? BP_NO : BP_YES;
+}
+
+static int battery_init(void)
+{
+	int batt_status;
+
+	return battery_status(&batt_status) ? 0 :
+		!!(batt_status & STATUS_INITIALIZED);
+}
+
+/* Allow booting now that the battery has woke up */
+static void battery_now_present(void)
+{
+	CPRINTS("battery will now report present");
+	battery_report_present = 1;
+}
+DECLARE_DEFERRED(battery_now_present);
+
+static int battery_check_disconnect(void)
+{
+	/* TODO(ecgh): Read the status of charge/discharge FETs */
+	return BATTERY_NOT_DISCONNECTED;
+}
+
+enum battery_present battery_is_present(void)
+{
+	enum battery_present batt_pres;
+	static int battery_report_present_timer_started;
+
+	/* Get the physical hardware status */
+	batt_pres = battery_hw_present();
+
+	/*
+	 * Make sure battery status is implemented, I2C transactions are
+	 * success & the battery status is Initialized to find out if it
+	 * is a working battery and it is not in the cut-off mode.
+	 */
+	if (batt_pres == BP_YES && batt_pres_prev != batt_pres &&
+	    (battery_is_cut_off() != BATTERY_CUTOFF_STATE_NORMAL ||
+	     battery_check_disconnect() != BATTERY_NOT_DISCONNECTED ||
+	     battery_init() == 0)) {
+		battery_report_present = 0;
+		/*
+		 * When this path is taken, the _timer_started flag must be
+		 * reset so the 'else if' path will be entered and the
+		 * battery_report_present flag can be set by the deferred
+		 * call. This handles the case of the battery being disconected
+		 * and reconnected while running or if battery_init() returns an
+		 * error due to a failed sb_read.
+		 */
+		battery_report_present_timer_started = 0;
+	}  else if (batt_pres == BP_YES && batt_pres_prev == BP_NO &&
+		   !battery_report_present_timer_started) {
+		/*
+		 * Wait 1/2 second before reporting present if it was
+		 * previously reported as not present
+		 */
+		battery_report_present_timer_started = 1;
+		battery_report_present = 0;
+		hook_call_deferred(&battery_now_present_data, 500 * MSEC);
+	}
+
+	if (!battery_report_present)
+		batt_pres = BP_NO;
+
+	batt_pres_prev = batt_pres;
+
+	return batt_pres;
+}
diff --git a/board/grunt/board.c b/board/grunt/board.c
index 597ff0fa10..1257a74a88 100644
--- a/board/grunt/board.c
+++ b/board/grunt/board.c
@@ -324,9 +324,17 @@ void board_reset_pd_mcu(void)
 
 void board_tcpc_init(void)
 {
+	int count = 0;
 	int port;
 
-	/* TODO(ecgh): need to wait for disconnected battery? */
+	/* Wait for disconnected battery to wake up */
+	while (battery_hw_present() == BP_YES &&
+	       battery_is_present() == BP_NO) {
+		usleep(100 * MSEC);
+		/* Give up waiting after 1 second */
+		if (++count > 10)
+			break;
+	}
 
 	/* Only reset TCPC if not sysjump */
 	if (!system_jumped_to_this_image())
diff --git a/board/grunt/board.h b/board/grunt/board.h
index f656c73b9c..824e7d7714 100644
--- a/board/grunt/board.h
+++ b/board/grunt/board.h
@@ -45,7 +45,8 @@
 #define CONFIG_VOLUME_BUTTONS
 
 #define CONFIG_BATTERY_CUT_OFF
-#define CONFIG_BATTERY_PRESENT_GPIO GPIO_EC_BATT_PRES_ODL
+#define CONFIG_BATTERY_HW_PRESENT_CUSTOM
+#define CONFIG_BATTERY_PRESENT_CUSTOM
 #define CONFIG_BATTERY_SMART
 
 #define CONFIG_BC12_DETECT_BQ24392