Add console command to fake battery state of charge

The new 'battfake' command is really handy for testing low-battery
shutdown logic.

BUG=chrome-os-partner:17124
BRANCH=link
TEST=from EC console:
	  reboot
	  battfake -> using real battery level
	  power on system -> lightbar should be blue
	  battfake 5
	  lightbar turns red after a few seconds
	  UI shows battery is very low
	     (shows <5% due to different kernel math)
	  'ectool battery' from root shell shows present capacity ~5% of
	  	  design capacity
	  remove AC power
	  battfake 4
	  UI shows low-battery screen and shuts down (may take a minute)
	  battfake 50
	  power on system
	  UI shows battery at 45-55%
	  battfake 2 -> system shuts down immediately
	  battfake -1
	  power on system
	  UI shows actual battery level

Original-Change-Id: I3180e321241c0f586f3baad2150fb6a2b2d2e242
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/43151
Reviewed-by: Bill Richardson <wfrichar@chromium.org>
(cherry picked from commit 695289cfe6724ad349a96d1f36ddf036b3df5daa)

Conflicts:
	common/charge_state.c

Change-Id: I95b020d1a747bafed0351d982eac1d314ea22301
Reviewed-on: https://gerrit.chromium.org/gerrit/44688
Commit-Queue: Randall Spangler <rspangler@chromium.org>
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Tested-by: Randall Spangler <rspangler@chromium.org>

2 files changed, 60 insertions, 21 deletions

diff --git a/common/charge_state.c b/common/charge_state.c
index ddf11f6c7e..da5f19c6ed 100644
--- a/common/charge_state.c
+++ b/common/charge_state.c
@@ -41,6 +41,8 @@ static int state_machine_force_idle = 0;
 
 static unsigned user_current_limit = -1U;
 
+static int fake_state_of_charge = -1;
+
 /* Current power state context */
 static struct power_state_context task_ctx;
 
@@ -217,16 +219,15 @@ static int state_common(struct power_state_context *ctx)
 	*ctx->memmap_batt_rate = batt->current < 0 ?
 		-batt->current : batt->current;
 
-	rv = battery_desired_voltage(&batt->desired_voltage);
-	if (rv)
+	if (battery_desired_voltage(&batt->desired_voltage))
 		curr->error |= F_DESIRED_VOLTAGE;
 
-	rv = battery_desired_current(&batt->desired_current);
-	if (rv)
+	if (battery_desired_current(&batt->desired_current))
 		curr->error |= F_DESIRED_CURRENT;
 
-	rv = battery_state_of_charge(&batt->state_of_charge);
-	if (rv)
+	if (fake_state_of_charge >= 0)
+		batt->state_of_charge = fake_state_of_charge;
+	else if (battery_state_of_charge(&batt->state_of_charge))
 		curr->error |= F_BATTERY_STATE_OF_CHARGE;
 
 	if (batt->state_of_charge != prev->batt.state_of_charge) {
@@ -281,22 +282,21 @@ static int state_common(struct power_state_context *ctx)
 	if (batt->desired_current > user_current_limit)
 		batt->desired_current = user_current_limit;
 
-	rv = battery_get_battery_mode(&d);
-	if (rv) {
+	if (battery_get_battery_mode(&d)) {
 		curr->error |= F_BATTERY_MODE;
-	} else {
-		if (d & MODE_CAPACITY) {
-			/* Battery capacity mode was set to mW
-			 * reset it back to mAh
-			 */
-			d &= ~MODE_CAPACITY;
-			rv = battery_set_battery_mode(d);
-			if (rv)
-				ctx->curr.error |= F_BATTERY_MODE;
-		}
+	} else if (d & MODE_CAPACITY) {
+		/* Battery capacity mode was set to mW reset it back to mAh */
+		d &= ~MODE_CAPACITY;
+		rv = battery_set_battery_mode(d);
+		if (rv)
+			ctx->curr.error |= F_BATTERY_MODE;
 	}
-	rv = battery_remaining_capacity(&d);
-	if (rv)
+
+	if (fake_state_of_charge >= 0)
+		*ctx->memmap_batt_cap =
+			fake_state_of_charge *
+			*(int *)host_get_memmap(EC_MEMMAP_BATT_LFCC) / 100;
+	else if (battery_remaining_capacity(&d))
 		ctx->curr.error |= F_BATTERY_CAPACITY;
 	else
 		*ctx->memmap_batt_cap = d;
@@ -568,6 +568,12 @@ int charge_get_percent(void)
 	return task_ctx.curr.batt.state_of_charge;
 }
 
+int charge_want_shutdown(void)
+{
+	return (charge_get_state() == PWR_STATE_DISCHARGE) &&
+		charge_get_percent() < BATTERY_LEVEL_SHUTDOWN;
+}
+
 static int enter_force_idle_mode(void)
 {
 	if (!power_ac_present())
@@ -860,3 +866,31 @@ static int charge_command_current_limit(struct host_cmd_handler_args *args)
 }
 DECLARE_HOST_COMMAND(EC_CMD_CHARGE_CURRENT_LIMIT, charge_command_current_limit,
 		     EC_VER_MASK(0));
+
+/*****************************************************************************/
+/* Console commands */
+
+static int command_battfake(int argc, char **argv)
+{
+	char *e;
+	int v;
+
+	if (argc == 2) {
+		v = strtoi(argv[1], &e, 0);
+		if (*e || v < -1 || v > 100)
+			return EC_ERROR_PARAM1;
+
+		fake_state_of_charge = v;
+	}
+
+	if (fake_state_of_charge < 0)
+		ccprintf("Reporting real battery level\n");
+	else
+		ccprintf("Reporting fake battery level %d%%\n",
+			 fake_state_of_charge);
+	return EC_SUCCESS;
+}
+DECLARE_CONSOLE_COMMAND(battfake, command_battfake,
+			"percent (-1 = use real level)",
+			"Set fake battery level",
+			NULL);
diff --git a/include/charge_state.h b/include/charge_state.h
index eda78abfd9..455426f1ed 100644
--- a/include/charge_state.h
+++ b/include/charge_state.h
@@ -1,4 +1,4 @@
-/* Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
+/* 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.
  *
@@ -134,5 +134,10 @@ enum power_state charge_get_state(void);
  */
 int charge_get_percent(void);
 
+/**
+ * Return non-zero if discharging and battery so low we should shut down.
+ */
+int charge_want_shutdown(void);
+
 #endif /* __CROS_EC_CHARGE_STATE_H */