1 files changed, 260 insertions, 0 deletions
diff --git a/board/constitution/led.c b/board/constitution/led.c
new file mode 100644
index 0000000000..a8c725258b
--- /dev/null
+++ b/board/constitution/led.c
@@ -0,0 +1,260 @@
+/* Copyright 2023 The ChromiumOS Authors
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ * Power LED control for Brask.
+ * Solid green - active power
+ * Green flashing - suspended
+ * Red flashing - alert
+ * Solid red - critical
+ */
+
+#include "chipset.h"
+#include "console.h"
+#include "ec_commands.h"
+#include "gpio.h"
+#include "hooks.h"
+#include "led_common.h"
+#include "pwm.h"
+#include "timer.h"
+#include "util.h"
+
+#define CPRINTS(format, args...) cprints(CC_GPIO, format, ##args)
+
+/*
+ * Due to the CSME-Lite processing, upon startup the CPU transitions through
+ * S0->S3->S5->S3->S0, causing the LED to turn on/off/on, so
+ * delay turning off the LED during suspend/shutdown.
+ */
+#define LED_CPU_DELAY_MS (2000 * MSEC)
+
+const enum ec_led_id supported_led_ids[] = { EC_LED_ID_POWER_LED };
+const int supported_led_ids_count = ARRAY_SIZE(supported_led_ids);
+
+enum led_color {
+	LED_OFF = 0,
+	LED_RED,
+	LED_GREEN,
+
+	/* Number of colors, not a color itself */
+	LED_COLOR_COUNT
+};
+
+static int set_color_power(enum led_color color, int duty)
+{
+	int green = 0;
+	int red = 0;
+
+	if (duty < 0 || 100 < duty)
+		return EC_ERROR_UNKNOWN;
+
+	switch (color) {
+	case LED_OFF:
+		break;
+	case LED_GREEN:
+		green = 1;
+		break;
+	case LED_RED:
+		red = 1;
+		break;
+	default:
+		return EC_ERROR_UNKNOWN;
+	}
+
+	if (red)
+		pwm_set_duty(PWM_CH_LED_RED, duty);
+	else
+		pwm_set_duty(PWM_CH_LED_RED, 0);
+
+	if (green)
+		pwm_set_duty(PWM_CH_LED_GREEN, duty);
+	else
+		pwm_set_duty(PWM_CH_LED_GREEN, 0);
+
+	return EC_SUCCESS;
+}
+
+static int set_color(enum ec_led_id id, enum led_color color, int duty)
+{
+	switch (id) {
+	case EC_LED_ID_POWER_LED:
+		return set_color_power(color, duty);
+	default:
+		return EC_ERROR_UNKNOWN;
+	}
+}
+
+#define LED_PULSE_US (2 * SECOND)
+/* 40 msec for nice and smooth transition. */
+#define LED_PULSE_TICK_US (40 * MSEC)
+
+/*
+ * When pulsing is enabled, brightness is incremented by <duty_inc> every
+ * <interval> usec from 0 to 100% in LED_PULSE_US usec. Then it's decremented
+ * likewise in LED_PULSE_US usec.
+ */
+static struct {
+	uint32_t interval;
+	int duty_inc;
+	enum led_color color;
+	int duty;
+} led_pulse;
+
+#define CONFIG_TICK(interval, color) \
+	config_tick((interval), 100 / (LED_PULSE_US / (interval)), (color))
+
+static void config_tick(uint32_t interval, int duty_inc, enum led_color color)
+{
+	led_pulse.interval = interval;
+	led_pulse.duty_inc = duty_inc;
+	led_pulse.color = color;
+	led_pulse.duty = 0;
+}
+
+static void pulse_power_led(enum led_color color)
+{
+	set_color(EC_LED_ID_POWER_LED, color, led_pulse.duty);
+	if (led_pulse.duty + led_pulse.duty_inc > 100)
+		led_pulse.duty_inc = led_pulse.duty_inc * -1;
+	else if (led_pulse.duty + led_pulse.duty_inc < 0)
+		led_pulse.duty_inc = led_pulse.duty_inc * -1;
+	led_pulse.duty += led_pulse.duty_inc;
+}
+
+static void led_tick(void);
+DECLARE_DEFERRED(led_tick);
+static void led_tick(void)
+{
+	uint32_t elapsed;
+	uint32_t next = 0;
+	uint32_t start = get_time().le.lo;
+
+	if (led_auto_control_is_enabled(EC_LED_ID_POWER_LED))
+		pulse_power_led(led_pulse.color);
+	elapsed = get_time().le.lo - start;
+	next = led_pulse.interval > elapsed ? led_pulse.interval - elapsed : 0;
+	hook_call_deferred(&led_tick_data, next);
+}
+
+static void led_suspend(void)
+{
+	CONFIG_TICK(LED_PULSE_TICK_US, LED_GREEN);
+	led_tick();
+}
+DECLARE_DEFERRED(led_suspend);
+
+static void led_shutdown(void)
+{
+	if (led_auto_control_is_enabled(EC_LED_ID_POWER_LED))
+		set_color(EC_LED_ID_POWER_LED, LED_OFF, 0);
+}
+DECLARE_DEFERRED(led_shutdown);
+
+static void led_shutdown_hook(void)
+{
+	hook_call_deferred(&led_tick_data, -1);
+	hook_call_deferred(&led_suspend_data, -1);
+	hook_call_deferred(&led_shutdown_data, LED_CPU_DELAY_MS);
+}
+DECLARE_HOOK(HOOK_CHIPSET_SHUTDOWN, led_shutdown_hook, HOOK_PRIO_DEFAULT);
+
+static void led_suspend_hook(void)
+{
+	hook_call_deferred(&led_shutdown_data, -1);
+	hook_call_deferred(&led_suspend_data, LED_CPU_DELAY_MS);
+}
+DECLARE_HOOK(HOOK_CHIPSET_SUSPEND, led_suspend_hook, HOOK_PRIO_DEFAULT);
+
+static void led_resume(void)
+{
+	/*
+	 * Assume there is no race condition with led_tick, which also
+	 * runs in hook_task.
+	 */
+	hook_call_deferred(&led_tick_data, -1);
+	/*
+	 * Avoid invoking the suspend/shutdown delayed hooks.
+	 */
+	hook_call_deferred(&led_suspend_data, -1);
+	hook_call_deferred(&led_shutdown_data, -1);
+	if (led_auto_control_is_enabled(EC_LED_ID_POWER_LED))
+		set_color(EC_LED_ID_POWER_LED, LED_GREEN, 100);
+}
+DECLARE_HOOK(HOOK_CHIPSET_RESUME, led_resume, HOOK_PRIO_DEFAULT);
+
+void led_alert(int enable)
+{
+	if (enable) {
+		/* Overwrite the current signal */
+		config_tick(1 * SECOND, 100, LED_RED);
+		led_tick();
+	} else {
+		/* Restore the previous signal */
+		if (chipset_in_state(CHIPSET_STATE_ON))
+			led_resume();
+		else if (chipset_in_state(CHIPSET_STATE_SUSPEND))
+			led_suspend_hook();
+		else if (chipset_in_state(CHIPSET_STATE_ANY_OFF))
+			led_shutdown_hook();
+	}
+}
+
+void show_critical_error(void)
+{
+	hook_call_deferred(&led_tick_data, -1);
+	if (led_auto_control_is_enabled(EC_LED_ID_POWER_LED))
+		set_color(EC_LED_ID_POWER_LED, LED_RED, 100);
+}
+
+static int command_led(int argc, const char **argv)
+{
+	enum ec_led_id id = EC_LED_ID_POWER_LED;
+
+	if (argc < 2)
+		return EC_ERROR_PARAM_COUNT;
+
+	if (!strcasecmp(argv[1], "debug")) {
+		led_auto_control(id, !led_auto_control_is_enabled(id));
+		ccprintf("o%s\n", led_auto_control_is_enabled(id) ? "ff" : "n");
+	} else if (!strcasecmp(argv[1], "off")) {
+		set_color(id, LED_OFF, 0);
+	} else if (!strcasecmp(argv[1], "red")) {
+		set_color(id, LED_RED, 100);
+	} else if (!strcasecmp(argv[1], "green")) {
+		set_color(id, LED_GREEN, 100);
+	} else if (!strcasecmp(argv[1], "alert")) {
+		led_alert(1);
+	} else if (!strcasecmp(argv[1], "crit")) {
+		show_critical_error();
+	} else {
+		return EC_ERROR_PARAM1;
+	}
+	return EC_SUCCESS;
+}
+DECLARE_CONSOLE_COMMAND(led, command_led, "[debug|red|green|off|alert|crit]",
+			"Turn on/off LED.");
+
+void led_get_brightness_range(enum ec_led_id led_id, uint8_t *brightness_range)
+{
+	brightness_range[EC_LED_COLOR_RED] = 100;
+	brightness_range[EC_LED_COLOR_GREEN] = 100;
+}
+
+int led_set_brightness(enum ec_led_id id, const uint8_t *brightness)
+{
+	if (brightness[EC_LED_COLOR_RED])
+		return set_color(id, LED_RED, brightness[EC_LED_COLOR_RED]);
+	else if (brightness[EC_LED_COLOR_GREEN])
+		return set_color(id, LED_GREEN, brightness[EC_LED_COLOR_GREEN]);
+	else
+		return set_color(id, LED_OFF, 0);
+}
+__override void board_set_charge_limit(int port, int supplier, int charge_ma,
+				       int max_ma, int charge_mv)
+{
+	/* Blink alert if insufficient power per system_can_boot_ap(). */
+	int insufficient_power =
+		(charge_ma * charge_mv) <
+		(CONFIG_CHARGER_MIN_POWER_MW_FOR_POWER_ON * 1000);
+	led_alert(insufficient_power);
+}