Fennel: Modify it8801 keyboard backlight driver and Enable keyboard backlight

1.Modify it8801 keyboard backlight driver code
2.Enable keyboard backlight setting with it8801 keyboard backlight driver

BUG=b:162902808
BRANCH=firmware-kukui-12573.B
TEST=Manual.
   Build and flash BIOS&EC on fennel board.
   Verify the keyboard backlight function.

Signed-off-by: Mike Lee <mike5@huaqin.corp-partner.google.com>
Change-Id: I73dd7ffc7b6ee80ed7ca39ac4d05afe65f666181
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2425988
Reviewed-by: Zhuohao Lee <zhuohao@chromium.org>
Commit-Queue: Zhuohao Lee <zhuohao@chromium.org>

5 files changed, 98 insertions, 9 deletions

diff --git a/board/fennel/board.c b/board/fennel/board.c
index 335a1bb486..0499be2585 100644
--- a/board/fennel/board.c
+++ b/board/fennel/board.c
@@ -30,6 +30,7 @@
 #include "i2c_bitbang.h"
 #include "it8801.h"
 #include "keyboard_scan.h"
+#include "keyboard_backlight.h"
 #include "lid_switch.h"
 #include "power.h"
 #include "power_button.h"
@@ -409,6 +410,38 @@ struct motion_sensor_t motion_sensors[] = {
 };
 const unsigned int motion_sensor_count = ARRAY_SIZE(motion_sensors);
 
+const struct it8801_pwm_t it8801_pwm_channels[] = {
+	[IT8801_PWM_CH_KBLIGHT] = {.index = 4},
+};
+
+void board_kblight_init(void)
+{
+	kblight_register(&kblight_it8801);
+}
+
+bool board_has_kb_backlight(void)
+{
+	/* Default enable keyboard backlight */
+	return true;
+}
+
+/* Called on AP S0iX -> S0 transition */
+static void board_chipset_resume(void)
+{
+	if (board_has_kb_backlight())
+		ioex_set_level(IOEX_KB_BL_EN, 1);
+}
+DECLARE_HOOK(HOOK_CHIPSET_RESUME, board_chipset_resume, HOOK_PRIO_DEFAULT);
+DECLARE_HOOK(HOOK_INIT, board_chipset_resume, HOOK_PRIO_DEFAULT);
+
+/* Called on AP S0 -> S0iX transition */
+static void board_chipset_suspend(void)
+{
+	if (board_has_kb_backlight())
+		ioex_set_level(IOEX_KB_BL_EN, 0);
+}
+DECLARE_HOOK(HOOK_CHIPSET_SUSPEND, board_chipset_suspend, HOOK_PRIO_DEFAULT);
+
 #endif /* !VARIANT_KUKUI_NO_SENSORS */
 
 /* Called on AP S5 -> S3 transition */
diff --git a/board/fennel/board.h b/board/fennel/board.h
index e0f013dc0d..ab036dc476 100644
--- a/board/fennel/board.h
+++ b/board/fennel/board.h
@@ -61,6 +61,9 @@
 
 #define CONFIG_ACCEL_FORCE_MODE_MASK BIT(LID_ACCEL)
 
+#define CONFIG_IO_EXPANDER_IT8801_PWM
+#define CONFIG_KEYBOARD_BACKLIGHT
+
 #endif /* VARIANT_KUKUI_NO_SENSORS */
 
 /* I2C ports */
@@ -123,6 +126,10 @@ enum battery_type {
 	BATTERY_TYPE_COUNT,
 };
 
+enum pwm_channel {
+	IT8801_PWM_CH_KBLIGHT = 0,
+};
+
 #include "gpio_signal.h"
 #include "registers.h"
 
diff --git a/board/fennel/gpio.inc b/board/fennel/gpio.inc
index 6f531634a1..7aed6abfc2 100644
--- a/board/fennel/gpio.inc
+++ b/board/fennel/gpio.inc
@@ -87,6 +87,7 @@ GPIO(USB_C0_DISCHARGE,     PIN(B, 6),  GPIO_OUT_LOW)
 IOEX(LED_BLUE,             EXPIN(0, 1, 4), GPIO_OUT_HIGH)      /* LED BLUE */
 IOEX(LED_GREEN,            EXPIN(0, 1, 3), GPIO_OUT_HIGH)      /* LED GREEN */
 IOEX(LED_ORANGE,           EXPIN(0, 1, 2), GPIO_OUT_HIGH)      /* LED ORANGE */
+IOEX(KB_BL_EN,             EXPIN(0, 0, 7), GPIO_OUT_LOW)
 
 /*
  * TODO(b:138352732): On IT88801 expander, To be readded once IT8801 driver and
diff --git a/driver/ioexpander/it8801.c b/driver/ioexpander/it8801.c
index 2f560a4468..df6ea3e76e 100644
--- a/driver/ioexpander/it8801.c
+++ b/driver/ioexpander/it8801.c
@@ -14,6 +14,7 @@
 #include "registers.h"
 #include "task.h"
 #include "util.h"
+#include "keyboard_backlight.h"
 
 #define CPRINTS(format, args...) cprints(CC_KEYSCAN, format, ## args)
 
@@ -430,16 +431,17 @@ DECLARE_CONSOLE_COMMAND(it8801_dump, it8801_dump, "NULL",
 struct it8801_pwm_gpio_map {
 	int port;
 	int mask;
+	int pushpull_en;
 };
 
 const static struct it8801_pwm_gpio_map it8801_pwm_gpio_map[] = {
-	[1] = {.port = 1, .mask = BIT(2)},
-	[2] = {.port = 1, .mask = BIT(3)},
-	[3] = {.port = 1, .mask = BIT(4)},
-	[4] = {.port = 1, .mask = BIT(5)},
-	[7] = {.port = 2, .mask = BIT(0)},
-	[8] = {.port = 2, .mask = BIT(3)},
-	[9] = {.port = 2, .mask = BIT(2)},
+	[1] = {.port = 1, .mask = BIT(2), .pushpull_en = BIT(0)},
+	[2] = {.port = 1, .mask = BIT(3), .pushpull_en = BIT(1)},
+	[3] = {.port = 1, .mask = BIT(4), .pushpull_en = BIT(2)},
+	[4] = {.port = 1, .mask = BIT(5), .pushpull_en = BIT(3)},
+	[7] = {.port = 2, .mask = BIT(0), .pushpull_en = BIT(4)},
+	[8] = {.port = 2, .mask = BIT(3), .pushpull_en = BIT(5)},
+	[9] = {.port = 2, .mask = BIT(2), .pushpull_en = BIT(6)},
 };
 
 void it8801_pwm_enable(enum pwm_channel ch, int enabled)
@@ -470,9 +472,19 @@ void it8801_pwm_enable(enum pwm_channel ch, int enabled)
 	if (enabled)
 		val |= IT8801_PWMMCR_MCR_BLINKING;
 	it8801_write(IT8801_REG_PWMMCR(it8801_pwm_channels[ch].index), val);
+
+	/*
+	 * 1: enable push pull function
+	 */
+	it8801_read(IT8801_REG_PWMODDSR, &val);
+	val &= ~it8801_pwm_gpio_map[index].pushpull_en;
+	if (enabled)
+		val |= it8801_pwm_gpio_map[index].pushpull_en;
+	it8801_write(IT8801_REG_PWMODDSR, val);
+
 }
 
-int it88801_pwm_get_enabled(enum pwm_channel ch)
+int it8801_pwm_get_enabled(enum pwm_channel ch)
 {
 	int val;
 
@@ -507,4 +519,38 @@ int it8801_pwm_get_duty(enum pwm_channel ch)
 	return 100 - it8801_pwm_get_raw_duty(ch) * 100 / 255;
 }
 
+#if defined(SECTION_IS_RW) && defined(CONFIG_KEYBOARD_BACKLIGHT)
+const enum pwm_channel it8801_kblight_pwm_ch = IT8801_PWM_CH_KBLIGHT;
+
+static int it8801_kblight_enable(int enable)
+{
+	it8801_pwm_enable(it8801_kblight_pwm_ch, enable);
+	return EC_SUCCESS;
+}
+
+static int it8801_kblight_set_brightness(int percent)
+{
+	it8801_pwm_set_duty(it8801_kblight_pwm_ch, percent);
+	return EC_SUCCESS;
+}
+
+static int it8801_kblight_get_brightness(void)
+{
+	return it8801_pwm_get_duty(it8801_kblight_pwm_ch);
+}
+
+static int it8801_kblight_init(void)
+{
+	it8801_pwm_set_duty(it8801_kblight_pwm_ch, 0);
+	it8801_pwm_enable(it8801_kblight_pwm_ch, 1);
+	return EC_SUCCESS;
+}
+
+const struct kblight_drv kblight_it8801 = {
+	.init = it8801_kblight_init,
+	.set = it8801_kblight_set_brightness,
+	.get = it8801_kblight_get_brightness,
+	.enable = it8801_kblight_enable,
+};
+#endif
 #endif  /* CONFIG_IO_EXPANDER_IT8801_PWM */
diff --git a/driver/ioexpander/it8801.h b/driver/ioexpander/it8801.h
index 016412ca22..25a82fe617 100644
--- a/driver/ioexpander/it8801.h
+++ b/driver/ioexpander/it8801.h
@@ -95,15 +95,17 @@ struct it8801_pwm_t {
 };
 
 extern const struct it8801_pwm_t it8801_pwm_channels[];
+extern const struct kblight_drv kblight_it8801;
 
 /* standard pwm interface as defined in pwm.h */
 void it8801_pwm_enable(enum pwm_channel ch, int enabled);
-int it88801_pwm_get_enabled(enum pwm_channel ch);
+int it8801_pwm_get_enabled(enum pwm_channel ch);
 void it8801_pwm_set_raw_duty(enum pwm_channel ch, uint16_t duty);
 uint16_t it8801_pwm_get_raw_duty(enum pwm_channel ch);
 void it8801_pwm_set_duty(enum pwm_channel ch, int percent);
 int it8801_pwm_get_duty(enum pwm_channel ch);
 
+#define IT8801_REG_PWMODDSR                            0x5F
 #define IT8801_REG_PWMMCR(n)            (0x60 + ((n) - 1) * 8)
 #define IT8801_REG_PWMDCR(n)            (0x64 + ((n) - 1) * 8)
 #define IT8801_REG_PWMPRSL(n)           (0x66 + ((n) - 1) * 8)