led_pwm: Add CONFIG_LED_PWM_ACTIVE_CHARGE_PORT_ONLY.

This commit adds support for a feature for the common PWM controlled LED
behaviour to only show the charge state instead of including chipset
state and low battery state as well.  Additionally, this feature will
only illuminate the LED of the active charge port.

BUG=b:69138917
BRANCH=None
TEST=Enable option on nocturne and verify behavior is as expected.

Change-Id: Ie6a767084c9102ff9b7bdad9288fcebf2ed9706f
Signed-off-by: Aseda Aboagye <aaboagye@google.com>
Reviewed-on: https://chromium-review.googlesource.com/1109032
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Tested-by: Aseda Aboagye <aaboagye@chromium.org>
Reviewed-by: Furquan Shaikh <furquan@chromium.org>

2 files changed, 99 insertions, 26 deletions

diff --git a/common/led_pwm.c b/common/led_pwm.c
index 6c1a190df9..17201fb03e 100644
--- a/common/led_pwm.c
+++ b/common/led_pwm.c
@@ -12,6 +12,7 @@
  */
 
 #include "battery.h"
+#include "charge_manager.h"
 #include "charge_state.h"
 #include "chipset.h"
 #include "common.h"
@@ -30,6 +31,27 @@
 
 #define PULSE_TICK (250 * MSEC)
 
+static uint8_t led_is_pulsing;
+
+static int ignore_set_led_color(enum pwm_led_id id, int color)
+{
+#ifdef CONFIG_LED_PWM_ACTIVE_CHARGE_PORT_ONLY
+	int active_chg_port = charge_manager_get_active_charge_port();
+
+	/* We should always be able to turn off a LED.*/
+	if (color == -1)
+		return 0;
+
+	if (led_is_pulsing)
+		return 0;
+
+	if ((int)id != active_chg_port)
+		return 1;
+#endif /* CONFIG_LED_PWM_ACTIVE_CHARGE_PORT_ONLY */
+
+	return 0;
+}
+
 void set_pwm_led_color(enum pwm_led_id id, int color)
 {
 	struct pwm_led duty = { 0 };
@@ -60,18 +82,27 @@ static void set_led_color(int color)
 	 */
 	if ((led_auto_control_is_enabled(EC_LED_ID_POWER_LED)) ||
 	    (led_auto_control_is_enabled(EC_LED_ID_LEFT_LED)))
-		set_pwm_led_color(PWM_LED0, color);
+		if (!ignore_set_led_color(PWM_LED0, color))
+			set_pwm_led_color(PWM_LED0, color);
 
 #if CONFIG_LED_PWM_COUNT >= 2
 	if (led_auto_control_is_enabled(EC_LED_ID_RIGHT_LED))
-		set_pwm_led_color(PWM_LED1, color);
+		if (!ignore_set_led_color(PWM_LED1, color))
+			set_pwm_led_color(PWM_LED1, color);
 #endif /* CONFIG_LED_PWM_COUNT >= 2 */
 }
 
-static uint8_t led_is_pulsing;
+static void init_leds_off(void)
+{
+	/* Turn off LEDs such that they are in a known state. */
+	set_led_color(-1);
+}
+DECLARE_HOOK(HOOK_INIT, init_leds_off, HOOK_PRIO_INIT_PWM + 1);
+
 static uint8_t pulse_period;
 static uint8_t pulse_ontime;
 static enum ec_led_colors pulse_color;
+static void update_leds(void);
 static void pulse_leds_deferred(void);
 DECLARE_DEFERRED(pulse_leds_deferred);
 static void pulse_leds_deferred(void)
@@ -80,6 +111,7 @@ static void pulse_leds_deferred(void)
 
 	if (!led_is_pulsing) {
 		tick_count = 0;
+		update_leds();
 		return;
 	}
 
@@ -101,21 +133,16 @@ static void pulse_leds(enum ec_led_colors color, int ontime, int period)
 	pulse_leds_deferred();
 }
 
-static void update_leds(void)
+static int show_charge_state(void)
 {
 	enum charge_state chg_st = charge_get_state();
-	int batt_percentage = charge_get_percent();
 
 	/*
-	 * Reflecting the charge state is the highest priority.
-	 *
 	 * The colors listed below are the default, but can be overridden.
 	 *
 	 * Solid Amber == Charging
 	 * Solid Green == Charging (near full)
 	 * Fast Flash Red == Charging error or battery not present
-	 * Slow Flash Amber == Low Battery
-	 * Fast Flash Amber == Critical Battery
 	 */
 	if (chg_st == PWR_STATE_CHARGE) {
 		led_is_pulsing = 0;
@@ -127,35 +154,72 @@ static void update_leds(void)
 		   (chg_st == PWR_STATE_ERROR)) {
 		/* 500 ms period, 50% duty cycle. */
 		pulse_leds(CONFIG_LED_PWM_CHARGE_ERROR_COLOR, 1, 2);
-	} else if (batt_percentage < CRITICAL_LOW_BATTERY_PERCENTAGE) {
+	} else {
+		/* Discharging or not charging. */
+		return 0;
+	}
+	return 1;
+}
+
+#ifndef CONFIG_LED_PWM_ACTIVE_CHARGE_PORT_ONLY
+static int show_battery_state(void)
+{
+	int batt_percentage = charge_get_percent();
+
+	/*
+	 * The colors listed below are the default, but can be overridden.
+	 *
+	 * Fast Flash Amber == Critical Battery
+	 * Slow Flash Amber == Low Battery
+	 */
+	if (batt_percentage < CRITICAL_LOW_BATTERY_PERCENTAGE) {
 		/* Flash amber faster (1 second period, 50% duty cycle) */
 		pulse_leds(CONFIG_LED_PWM_LOW_BATT_COLOR, 2, 4);
 	} else if (batt_percentage < LOW_BATTERY_PERCENTAGE) {
 		/* Flash amber (4 second period, 50% duty cycle) */
 		pulse_leds(CONFIG_LED_PWM_LOW_BATT_COLOR, 8, 16);
 	} else {
-		/* Discharging or not charging. Reflect the SoC state. */
-		led_is_pulsing = 0;
-		if (chipset_in_state(CHIPSET_STATE_ON)) {
-			/* The LED must be on in the Active state. */
-			set_led_color(CONFIG_LED_PWM_SOC_ON_COLOR);
-		} else if (chipset_in_state(CHIPSET_STATE_ANY_SUSPEND)) {
-			/* The power LED must pulse in the suspend state. */
-			pulse_leds(CONFIG_LED_PWM_SOC_SUSPEND_COLOR, 4, 16);
-		} else if (chipset_in_state(CHIPSET_STATE_ANY_OFF)) {
-			/* The LED must be off in the Deep Sleep state. */
-			set_led_color(-1);
-		}
+		/* Sufficient charge, no need to show anything for this. */
+		return 0;
 	}
+	return 1;
 }
-DECLARE_HOOK(HOOK_TICK, update_leds, HOOK_PRIO_DEFAULT);
 
-static void init_leds_off(void)
+static int show_chipset_state(void)
 {
-	/* Turn off LEDs such that they are in a known state. */
+	/* Reflect the SoC state. */
+	led_is_pulsing = 0;
+	if (chipset_in_state(CHIPSET_STATE_ON)) {
+		/* The LED must be on in the Active state. */
+		set_led_color(CONFIG_LED_PWM_SOC_ON_COLOR);
+	} else if (chipset_in_state(CHIPSET_STATE_ANY_SUSPEND)) {
+		/* The power LED must pulse in the suspend state. */
+		pulse_leds(CONFIG_LED_PWM_SOC_SUSPEND_COLOR, 4, 16);
+	} else {
+		/* Chipset is off, no need to show anything for this. */
+		return 0;
+	}
+	return 1;
+}
+#endif /* CONFIG_LED_PWM_ACTIVE_CHARGE_PORT_ONLY */
+
+static void update_leds(void)
+{
+	/* Reflecting the charge state is the highest priority. */
+	if (show_charge_state())
+		return;
+
+#ifndef CONFIG_LED_PWM_ACTIVE_CHARGE_PORT_ONLY
+	if (show_battery_state())
+		return;
+
+	if (show_chipset_state())
+		return;
+#endif /* CONFIG_LED_PWM_ACTIVE_CHARGE_PORT_ONLY */
+
 	set_led_color(-1);
 }
-DECLARE_HOOK(HOOK_INIT, init_leds_off, HOOK_PRIO_INIT_PWM + 1);
+DECLARE_HOOK(HOOK_TICK, update_leds, HOOK_PRIO_DEFAULT);
 
 #ifdef CONFIG_CMD_LEDTEST
 int command_ledtest(int argc, char **argv)
diff --git a/include/config.h b/include/config.h
index 7e4c2168d0..42cbe178ec 100644
--- a/include/config.h
+++ b/include/config.h
@@ -2018,6 +2018,15 @@
 #define CONFIG_LED_PWM_LOW_BATT_COLOR EC_LED_COLOR_AMBER
 
 /*
+ * By default the PWM LED behaviour is reflected on both LEDs and includes the
+ * chipset state, battery state, as well as the charging state.  However, enable
+ * this CONFIG_* option to only allow the charging state to be reflected on the
+ * LEDs.  Additionally, only the active charge port will indicate the charge
+ * state.
+ */
+#undef CONFIG_LED_PWM_ACTIVE_CHARGE_PORT_ONLY
+
+/*
  * How many PWM LEDs does the system have that will be controlled by the common
  * PWM LED policy?  Currently, this may be at most 2.
  */