coral: Add support for power LED for Robo devices

Robo devices have a power button LED. For these devices the desried
power button LED behavior is:
S0 -> always on
S3 -> charging, then 500 mSec off, 3 seconds on
S3 -> not charging, always off
S5 -> always off

Because the hook tick runs at 200 msec, using 600 msec for the off
period when blinking in S3.

BUG=b:64015212
BRANCH=None
TEST=Manual
This LED is not connected on EVT, so added a wire on GPIO02 and used a
scope. Verifed that in S0 the signal level is low, and in S3 that it
control signal toggles 600 mSec high/3 sec low. Verifed than in S5
control signal is high.

Change-Id: I72438a009a507fcddaae5a673bf3bc83988f2dd5
Signed-off-by: Scott Collyer <scollyer@google.com>
Reviewed-on: https://chromium-review.googlesource.com/717183
Commit-Ready: Scott Collyer <scollyer@chromium.org>
Tested-by: Scott Collyer <scollyer@chromium.org>
Reviewed-by: Patrick Georgi <pgeorgi@chromium.org>

2 files changed, 48 insertions, 6 deletions

diff --git a/board/coral/gpio.inc b/board/coral/gpio.inc
index f0a49f387e..642e1fb8d4 100644
--- a/board/coral/gpio.inc
+++ b/board/coral/gpio.inc
@@ -75,7 +75,6 @@ GPIO(PCH_SLP_S0_L,              PIN(7, 5), GPIO_INPUT)				/* SLP_S0_L */
 GPIO(EC_BRD_ID_EN,		PIN(3, 5), GPIO_INPUT)
 
 GPIO(CCD_MODE_ODL,		PIN(6, 3), GPIO_INPUT)
-GPIO(EC_HAVEN_RESET_ODL,	PIN(0, 2), GPIO_ODR_HIGH)
 GPIO(ENTERING_RW,		PIN(7, 6), GPIO_OUTPUT)			/* EC_ENTERING_RW */
 
 GPIO(PCH_RSMRST_L,		PIN(7, 0), GPIO_OUT_LOW)
@@ -131,8 +130,9 @@ GPIO(USB_C1_PD_RST_ODL,		PIN(7, 4), GPIO_ODR_LOW)
 GPIO(USB_C0_5V_EN,		PIN(D, 3), GPIO_OUT_LOW | GPIO_PULL_UP)	/* EN_USB_C0_5V_OUT, Enable C0 */
 GPIO(USB_C1_5V_EN,		PIN(D, 2), GPIO_OUT_LOW | GPIO_PULL_UP)	/* EN_USB_C1_5V_OUT, Enable C1 */
 
-GPIO(BAT_LED_BLUE,		PIN(8,  0), GPIO_OUT_HIGH)
-GPIO(BAT_LED_AMBER,		PIN(C,  4), GPIO_OUT_HIGH)
+GPIO(BAT_LED_BLUE,		PIN(8, 0), GPIO_OUT_HIGH)
+GPIO(BAT_LED_AMBER,		PIN(C, 4), GPIO_OUT_HIGH)
+GPIO(POWER_LED,			PIN(0, 2), GPIO_OUT_HIGH)
 
 
 /*
diff --git a/board/coral/led.c b/board/coral/led.c
index 671b02f228..6e26177522 100644
--- a/board/coral/led.c
+++ b/board/coral/led.c
@@ -23,6 +23,10 @@
 #define LED_ONE_SEC (1000 / HOOK_TICK_INTERVAL_MS)
 #define LED_CHARGE_LEVEL_1_DEFAULT 100
 #define LED_CHARGE_LEVEL_1_ROBO 5
+#define LED_POWER_BLINK_ON_MSEC 3000
+#define LED_POWER_BLINK_OFF_MSEC 600
+#define LED_POWER_ON_TICKS (LED_POWER_BLINK_ON_MSEC / HOOK_TICK_INTERVAL_MS)
+#define LED_POWER_OFF_TICKS (LED_POWER_BLINK_OFF_MSEC / HOOK_TICK_INTERVAL_MS)
 
 const enum ec_led_id supported_led_ids[] = {
 			EC_LED_ID_BATTERY_LED};
@@ -130,6 +134,11 @@ static int led_set_color_battery(enum led_color color)
 	return EC_SUCCESS;
 }
 
+static void led_set_color_power(int level)
+{
+	gpio_set_level(GPIO_POWER_LED, level);
+}
+
 void led_get_brightness_range(enum ec_led_id led_id, uint8_t *brightness_range)
 {
 	brightness_range[EC_LED_COLOR_BLUE] = 1;
@@ -241,12 +250,45 @@ static void led_update_battery(void)
 	ticks++;
 }
 
-/* Called by hook task every 1 sec */
+static void led_robo_update_power(void)
+{
+	int level;
+	static int ticks;
+
+	if (chipset_in_state(CHIPSET_STATE_ON)) {
+		/* In S0 power LED is always on */
+		level = LED_ON_LVL;
+		ticks = 0;
+	} else if ((chipset_in_state(CHIPSET_STATE_SUSPEND) |
+		   chipset_in_state(CHIPSET_STATE_STANDBY)) &&
+		   led.state <= STATE_CHARGING_LVL_3) {
+		int period;
+
+		/*
+		 * If in suspend/standby and the device is charging, then the
+		 * power LED is off for 600 msec, on for 3 seconds.
+		 */
+		period = LED_POWER_ON_TICKS + LED_POWER_OFF_TICKS;
+		level = ticks % period < LED_POWER_OFF_TICKS ?
+			LED_OFF_LVL : LED_ON_LVL;
+		ticks++;
+	} else {
+		level = LED_OFF_LVL;
+		ticks = 0;
+	}
+
+	led_set_color_power(level);
+}
+
+/* Called by hook task every hook tick (200 msec) */
 static void led_update(void)
 {
 	/* Update battery LED */
-	if (led_auto_control_is_enabled(EC_LED_ID_BATTERY_LED))
+	if (led_auto_control_is_enabled(EC_LED_ID_BATTERY_LED)) {
 		led_update_battery();
+		if (led.update_power != NULL)
+			(*led.update_power)();
+	}
 }
 DECLARE_HOOK(HOOK_TICK, led_update, HOOK_PRIO_DEFAULT);
 
@@ -258,7 +300,7 @@ static void led_init(void)
 	    (sku >= 144 && sku <= 145)) {
 		led.charge_lvl_1 = LED_CHARGE_LEVEL_1_ROBO;
 		led.state_table = led_robo_state_table;
-		led.update_power = NULL;
+		led.update_power = led_robo_update_power;
 	} else {
 		led.charge_lvl_1 = LED_CHARGE_LEVEL_1_DEFAULT;
 		led.state_table = led_default_state_table;