Zephyr: adlrvp: Implement custom LED behavior

Implemented custom LED behavior for Intel RVP using PWM.

BUG=none
BRANCH=None
TEST=zmake build adlrvp_npcx
     Observed LED behviour

Signed-off-by: Rajesh Kumar <rajesh3.kumar@intel.com>
Change-Id: Ieb391dfe0c23e7b27211f23485f2720f7ac40a73
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3654481
Reviewed-by: Sam Hurst <shurst@google.com>
Reviewed-by: Vijay P Hiremath <vijay.p.hiremath@intel.com>

6 files changed, 274 insertions, 2 deletions

diff --git a/zephyr/projects/intelrvp/BUILD.py b/zephyr/projects/intelrvp/BUILD.py
index 20fc331b46..97956b9e2d 100644
--- a/zephyr/projects/intelrvp/BUILD.py
+++ b/zephyr/projects/intelrvp/BUILD.py
@@ -51,6 +51,7 @@ register_intelrvp_project(
         here / "adlrvp/adlrvp_npcx/keyboard.dts",
         here / "adlrvp/adlrvp_npcx/temp_sensor.dts",
         here / "adlrvp/adlrvp_npcx/usbc.dts",
+        here / "adlrvp/adlrvp_npcx/pwm_leds.dts",
     ],
     extra_kconfig_files=[
         here / "legacy_ec_pwrseq.conf",
diff --git a/zephyr/projects/intelrvp/CMakeLists.txt b/zephyr/projects/intelrvp/CMakeLists.txt
index 43a5877cd3..f8a76be55d 100644
--- a/zephyr/projects/intelrvp/CMakeLists.txt
+++ b/zephyr/projects/intelrvp/CMakeLists.txt
@@ -20,8 +20,7 @@ if(DEFINED CONFIG_BOARD_ADLRVP_NPCX)
   zephyr_library_sources_ifdef(CONFIG_PLATFORM_EC_USBC "${PLATFORM_EC}/baseboard/intelrvp/usb_pd_policy_mecc_1_0.c")
   zephyr_library_sources_ifdef(CONFIG_PLATFORM_EC_USBC "${PLATFORM_EC}/baseboard/intelrvp/chg_usb_pd_mecc_1_0.c")
   zephyr_library_sources_ifdef(CONFIG_PLATFORM_EC_USBC "${PLATFORM_EC}/baseboard/intelrvp/chg_usb_pd.c")
-  zephyr_library_sources_ifdef(CONFIG_PLATFORM_EC_LED_COMMON "${PLATFORM_EC}/baseboard/intelrvp/led.c")
-  zephyr_library_sources_ifdef(CONFIG_PLATFORM_EC_LED_COMMON "${PLATFORM_EC}/baseboard/intelrvp/led_states.c")
+  zephyr_library_sources_ifdef(CONFIG_PLATFORM_EC_LED_PWM "src/intel_rvp_led.c")
 endif()
 
 if(DEFINED CONFIG_BOARD_MTLRVP_NPCX)
diff --git a/zephyr/projects/intelrvp/adlrvp/adlrvp_npcx/pwm_leds.dts b/zephyr/projects/intelrvp/adlrvp/adlrvp_npcx/pwm_leds.dts
new file mode 100644
index 0000000000..50a08a300e
--- /dev/null
+++ b/zephyr/projects/intelrvp/adlrvp/adlrvp_npcx/pwm_leds.dts
@@ -0,0 +1,58 @@
+/* Copyright 2022 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.
+ */
+
+/ {
+	pwmleds {
+		compatible = "pwm-leds";
+		pwm_led0: pwm_led_0 {
+			pwms = <&pwm4 0 0 PWM_POLARITY_INVERTED>;
+		};
+		pwm_led1: pwm_led_1 {
+			pwms = <&pwm5 0 0 PWM_POLARITY_INVERTED>;
+		};
+	};
+
+	cros-pwmleds {
+		compatible = "cros-ec,pwm-leds";
+
+		leds = <&pwm_led0 &pwm_led1>;
+		frequency = <4800>;
+
+		color-map-green  = <100>;
+
+		/* brightness-range = <red green blue yellow white amber> */
+		brightness-range = <0 100 0 0 0 0>;
+
+
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		pwm_led_0@0 {
+			reg = <0>;
+			ec-led-name = "EC_LED_ID_BATTERY_LED";
+		};
+
+		pwm_led_1@1 {
+			reg = <1>;
+			ec-led-name = "EC_LED_ID_POWER_LED";
+		};
+	};
+};
+
+/* LED1 */
+&pwm4 {
+	status = "okay";
+	clock-bus = "NPCX_CLOCK_BUS_LFCLK";
+	pinctrl-0 = <&pwm4_gpb6>;
+	pinctrl-names = "default";
+};
+
+/* LED2 */
+&pwm5 {
+	status = "okay";
+	clock-bus = "NPCX_CLOCK_BUS_LFCLK";
+	pinctrl-0 = <&pwm5_gpb7>;
+	pinctrl-names = "default";
+};
diff --git a/zephyr/projects/intelrvp/adlrvp/prj.conf b/zephyr/projects/intelrvp/adlrvp/prj.conf
index 5b1a47ebf0..357b0bee66 100644
--- a/zephyr/projects/intelrvp/adlrvp/prj.conf
+++ b/zephyr/projects/intelrvp/adlrvp/prj.conf
@@ -35,6 +35,8 @@ CONFIG_PLATFORM_EC_CHARGER_RUNTIME_CONFIG=y
 
 # LED
 CONFIG_PLATFORM_EC_LED_COMMON=y
+CONFIG_PLATFORM_EC_LED_PWM=y
+CONFIG_PLATFORM_EC_LED_PWM_TASK_DISABLED=y
 
 # Temperature sensors
 CONFIG_PLATFORM_EC_TEMP_SENSOR=y
diff --git a/zephyr/projects/intelrvp/led.md b/zephyr/projects/intelrvp/led.md
new file mode 100644
index 0000000000..c36bc6b36c
--- /dev/null
+++ b/zephyr/projects/intelrvp/led.md
@@ -0,0 +1,44 @@
+## LED behavior on Intel RVP
+
+There are two LEDs on RVP, they represent battery and charger status
+respectively.
+
+LED         | Description
+------------|------------------------
+CHARGER_LED | Represent charger state
+BATTERY_LED | Represent battery state
+
+LEDs on RVP emit a single color (green). Rather than just using the on and off
+state of the LED, PWM is used to blink the LED to represent multiple states and
+the below table represents the multiple LED states.
+
+LED State      | Description
+---------------|------------------------------
+LED_ON         | Switch On using gpio/pwmduty
+LED_OFF        | Switch Off using gpio/pwmduty
+LED_FLASH_SLOW | Flashing with 2 sec period
+LED_FLASH_FAST | Flashing with 250ms period
+
+### LED Behavior : Charger
+
+CHARGER_LED is dedicated to represent Charger status and the below table
+represents the LED states for the Charger.
+
+Charger Status       | LED States
+---------------------|---------------
+Charging             | LED_ON
+Discharging          | LED_FLASH_SLOW
+Charging error       | LED_FLASH_FAST
+No Charger Connected | LED_OFF
+
+### LED Behavior : Battery
+
+BATTERY_LED is dedicated to represent Battery status and the below table
+represents the LED states for the Battery.
+
+Battery Status              | LED States
+----------------------------|---------------
+Battery Low (<10%)          | LED_FLASH_FAST
+Battery Normal (10% to 90%) | LED_FLASH_SLOW
+Battery Full (>90%)         | LED_ON
+Battery Not Present         | LED_OFF
diff --git a/zephyr/projects/intelrvp/src/intel_rvp_led.c b/zephyr/projects/intelrvp/src/intel_rvp_led.c
new file mode 100644
index 0000000000..b382dcc485
--- /dev/null
+++ b/zephyr/projects/intelrvp/src/intel_rvp_led.c
@@ -0,0 +1,168 @@
+/* Copyright 2022 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.
+ */
+
+#include "battery.h"
+#include "charge_manager.h"
+#include "charge_state.h"
+#include "chipset.h"
+#include "common.h"
+#include "console.h"
+#include "ec_commands.h"
+#include "extpower.h"
+#include "hooks.h"
+#include "led_common.h"
+#include "led_pwm.h"
+#include "pwm.h"
+#include "timer.h"
+#include "util.h"
+
+/* Battery percentage thresholds to blink at different rates. */
+#define LOW_BATTERY_PERCENTAGE 10
+#define NORMAL_BATTERY_PERCENTAGE 90
+
+#define LED_OFF -1
+
+#define LED_PULSE_TICK (125 * MSEC)
+
+#define LED_FAST_PULSE_PERIOD  (250 / 125)		/* 250 ms */
+#define LED_SLOW_PULSE_PERIOD  ((2 * MSEC) / 125)	/* 2 sec  */
+
+struct led_pulse_data {
+	bool led_is_pulsing;
+	uint8_t led_pulse_period;
+	uint8_t led_tick_count;
+};
+
+static struct led_pulse_data rvp_led[CONFIG_LED_PWM_COUNT];
+
+static void pulse_led_deferred(void);
+DECLARE_DEFERRED(pulse_led_deferred);
+
+static void pulse_led_deferred(void)
+{
+	int i = 0;
+	bool call_deferred = false;
+
+	for (i = 0; i < CONFIG_LED_PWM_COUNT; i++) {
+		if (!rvp_led[i].led_is_pulsing) {
+			rvp_led[i].led_tick_count = 0;
+			continue;
+		}
+
+		/*
+		 * LED will be in ON state first half of the pulse period
+		 * and in OFF state in second half of the pulse period.
+		 */
+		if (rvp_led[i].led_tick_count <
+					(rvp_led[i].led_pulse_period >> 1))
+			set_pwm_led_color(i, EC_LED_COLOR_GREEN);
+		else
+			set_pwm_led_color(i, LED_OFF);
+
+		rvp_led[i].led_tick_count = (rvp_led[i].led_tick_count + 1) %
+						rvp_led[i].led_pulse_period;
+		call_deferred = true;
+	}
+
+	if (call_deferred)
+		hook_call_deferred(&pulse_led_deferred_data, LED_PULSE_TICK);
+}
+
+static void pulse_leds(enum pwm_led_id id, int period)
+{
+	rvp_led[id].led_pulse_period = period;
+	rvp_led[id].led_is_pulsing   = true;
+
+	pulse_led_deferred();
+}
+
+static void update_charger_led(enum pwm_led_id id)
+{
+	enum charge_state chg_st = charge_get_state();
+
+	/*
+	 * The colors listed below are the default, but can be overridden.
+	 *
+	 * Fast Flash = Charging error
+	 * Slow Flash = Discharging
+	 * LED on     = Charging
+	 * LED off    = No Charger connected
+	 */
+	if (chg_st == PWR_STATE_CHARGE ||
+	    chg_st == PWR_STATE_CHARGE_NEAR_FULL) {
+		/* Charging: LED ON */
+		rvp_led[id].led_is_pulsing = false;
+		set_pwm_led_color(id, EC_LED_COLOR_GREEN);
+	} else if (chg_st == PWR_STATE_DISCHARGE ||
+		  chg_st == PWR_STATE_DISCHARGE_FULL) {
+		if (extpower_is_present()) {
+			/* Discharging:
+			 * Flash slower (2 second period, 100% duty cycle)
+			 */
+			pulse_leds(id, LED_SLOW_PULSE_PERIOD);
+		} else {
+			/* No Charger connected: LED OFF */
+			rvp_led[id].led_is_pulsing = false;
+			set_pwm_led_color(id, LED_OFF);
+		}
+	} else if (chg_st == PWR_STATE_ERROR) {
+		/* Charging error:
+		 * Flash faster (250 ms period, 100% duty cycle)
+		 */
+		pulse_leds(id, LED_FAST_PULSE_PERIOD);
+	} else {
+		/* LED OFF */
+		rvp_led[id].led_is_pulsing = false;
+		set_pwm_led_color(id, LED_OFF);
+	}
+}
+
+static void update_battery_led(enum pwm_led_id id)
+{
+	/*
+	 * Fast Flash = Low Battery
+	 * Slow Flash = Normal Battery
+	 * LED on     = Full Battery
+	 * LED off    = No Battery
+	 */
+	if (battery_is_present() == BP_YES) {
+		int batt_percentage = charge_get_percent();
+
+		if (batt_percentage < LOW_BATTERY_PERCENTAGE) {
+			/* Low Battery:
+			 * Flash faster (250 ms period, 100% duty cycle)
+			 */
+			pulse_leds(id, LED_FAST_PULSE_PERIOD);
+		} else if (batt_percentage < NORMAL_BATTERY_PERCENTAGE) {
+			/* Normal Battery:
+			 * Flash slower (2 second period, 100% duty cycle)
+			 */
+			pulse_leds(id, LED_SLOW_PULSE_PERIOD);
+		} else {
+			/* Full Battery: LED ON */
+			rvp_led[id].led_is_pulsing = false;
+			set_pwm_led_color(id, EC_LED_COLOR_GREEN);
+		}
+	} else {
+		/* No Battery: LED OFF */
+		rvp_led[id].led_is_pulsing = false;
+		set_pwm_led_color(id, LED_OFF);
+	}
+}
+
+static void init_rvp_leds_off(void)
+{
+	/* Turn off LEDs such that they are in a known state with zero duty. */
+	set_pwm_led_color(PWM_LED0, LED_OFF);
+	set_pwm_led_color(PWM_LED1, LED_OFF);
+}
+DECLARE_HOOK(HOOK_INIT, init_rvp_leds_off, HOOK_PRIO_POST_PWM);
+
+static void update_led(void)
+{
+	update_battery_led(PWM_LED0);
+	update_charger_led(PWM_LED1);
+}
+DECLARE_HOOK(HOOK_SECOND, update_led, HOOK_PRIO_DEFAULT);