Quackingstick: Detect pen input and charge it

Use PEN_DETECT to detect if the pen input and
pull PEN_PWR_EN to charge/discharge the pen.

BUG=b:205163599
BRANCH=trogdor
TEST="make BOARD=quackingstick" pass

Signed-off-by: Sue Chen <sue.chen@quanta.corp-partner.google.com>
Change-Id: I5a3392c8f88ad372fc8e043fb24eb5cac3adaa86
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3351428
Reviewed-by: Bob Moragues <moragues@chromium.org>
Reviewed-by: Jack Rosenthal <jrosenth@chromium.org>

3 files changed, 34 insertions, 2 deletions

diff --git a/board/quackingstick/board.c b/board/quackingstick/board.c
index 856578db82..d0552b9f05 100644
--- a/board/quackingstick/board.c
+++ b/board/quackingstick/board.c
@@ -412,6 +412,10 @@ static void board_init(void)
 	 */
 	gpio_enable_interrupt(GPIO_CCD_MODE_ODL);
 
+	/* Enable pen input detect interrupt */
+	if (system_get_board_version() >= 2)
+		gpio_enable_interrupt(GPIO_EC_PEN_PDCT_L);
+
 	/* Set the backlight duty cycle to 0. AP will override it later. */
 	pwm_set_duty(PWM_CH_DISPLIGHT, 0);
 }
@@ -626,6 +630,33 @@ void board_set_charge_limit(int port, int supplier, int charge_ma,
 				       charge_mv);
 }
 
+/**
+ * Handle debounced pen input changing state.
+ */
+static void pen_input_deferred(void)
+{
+	bool pen_charge_enable = !gpio_get_level(GPIO_EC_PEN_PDCT_L) &&
+			!chipset_in_state(CHIPSET_STATE_ANY_OFF);
+
+	gpio_set_level(GPIO_PEN_PWR_EN, pen_charge_enable);
+
+	CPRINTS("Pen charge %sable", pen_charge_enable ? "en" : "dis");
+}
+DECLARE_DEFERRED(pen_input_deferred);
+
+void pen_input_interrupt(enum gpio_signal signal)
+{
+	/* pen input debounce time */
+	hook_call_deferred(&pen_input_deferred_data, (100 * MSEC));
+}
+
+static void pen_charge_check(void)
+{
+	hook_call_deferred(&pen_input_deferred_data, (100 * MSEC));
+}
+DECLARE_HOOK(HOOK_CHIPSET_STARTUP, pen_charge_check, HOOK_PRIO_LAST);
+DECLARE_HOOK(HOOK_CHIPSET_SHUTDOWN, pen_charge_check, HOOK_PRIO_LAST);
+
 uint16_t tcpc_get_alert_status(void)
 {
 	uint16_t status = 0;
diff --git a/board/quackingstick/board.h b/board/quackingstick/board.h
index 7ad8cd227c..0d412246ec 100644
--- a/board/quackingstick/board.h
+++ b/board/quackingstick/board.h
@@ -116,6 +116,7 @@ void board_set_tcpc_power_mode(int port, int mode);
 void base_detect_interrupt(enum gpio_signal signal);
 /* motion sensor interrupt */
 void motion_interrupt(enum gpio_signal signal);
+void pen_input_interrupt(enum gpio_signal signal);
 
 #endif /* !defined(__ASSEMBLER__) */
 
diff --git a/board/quackingstick/gpio.inc b/board/quackingstick/gpio.inc
index 09983989d2..c126b59977 100644
--- a/board/quackingstick/gpio.inc
+++ b/board/quackingstick/gpio.inc
@@ -39,6 +39,7 @@ GPIO_INT(BASE_DET_L,        PIN(3, 7), GPIO_INT_BOTH, base_detect_interrupt)  /*
 
 /* Sensor interrupts */
 GPIO_INT(ACCEL_GYRO_INT_L,  PIN(A, 0), GPIO_INT_FALLING, motion_interrupt)  /* Accelerometer/gyro interrupt */
+GPIO_INT(EC_PEN_PDCT_L,     PIN(5, 0), GPIO_INT_BOTH, pen_input_interrupt)  /* Pen input detect */
 
 /*
  * EC_RST_ODL acts as a wake source from hibernate mode. However, it does not
@@ -62,6 +63,7 @@ GPIO(EC_BL_DISABLE_L,       PIN(B, 6), GPIO_OUT_LOW)   /* Backlight disable sign
 
 /* Base detection */
 GPIO(EN_BASE,               PIN(0, 4), GPIO_OUT_LOW)   /* Enable power to detachable base */
+GPIO(PEN_PWR_EN,            PIN(8, 2), GPIO_OUT_LOW)   /* Pen input charge */
 
 /* USB-C */
 GPIO(USB_C0_PD_RST_L,       PIN(F, 1), GPIO_ODR_HIGH)  /* Port-0 TCPC chip reset, actaully Open-Drain */
@@ -122,12 +124,10 @@ GPIO(ARM_X86,               PIN(6, 6), GPIO_OUT_LOW)  /* NC, low for power savin
 /* Unused GPIOs, NC. Apply PU for power saving */
 UNUSED(PIN(F, 5))
 UNUSED(PIN(4, 0))
-UNUSED(PIN(8, 2))
 UNUSED(PIN(7, 4))
 UNUSED(PIN(7, 3))
 UNUSED(PIN(D, 7))
 UNUSED(PIN(6, 0))
-UNUSED(PIN(5, 0))
 UNUSED(PIN(C, 5))
 UNUSED(PIN(3, 0))
 UNUSED(PIN(E, 4))