Trogdor: Add the interrupt for USB-A overcurrent

The USB-A VBUS is through a load switch. The FAULT_L pin of
the load switch requires an external pull-up. Apply the pull-up
on EC side.

Add the interrupt of the FAULT_L pin. Route to the function
board_overcurrent_event(), which currently prints an error
message.

BRANCH=Trogdor
BUG=b:173154219
TEST=Plugged a USB load >1.5A to the USB-A port and checked
the error message was printed:
[73.738372 p2: overcurrent!]

Change-Id: I5f5f82de942eaf26a33051ad17f14b90d8024b89
Signed-off-by: Wai-Hong Tam <waihong@google.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2547190
Reviewed-by: Alexandru M Stan <amstan@chromium.org>

2 files changed, 21 insertions, 2 deletions

diff --git a/board/trogdor/board.c b/board/trogdor/board.c
index a17e961f60..9cf26f3e6a 100644
--- a/board/trogdor/board.c
+++ b/board/trogdor/board.c
@@ -31,6 +31,7 @@
 #include "shi_chip.h"
 #include "switch.h"
 #include "task.h"
+#include "usbc_ocp.h"
 #include "usbc_ppc.h"
 
 #define CPRINTS(format, args...) cprints(CC_USBCHARGE, format, ## args)
@@ -40,6 +41,7 @@
 static void tcpc_alert_event(enum gpio_signal signal);
 static void usb0_evt(enum gpio_signal signal);
 static void usb1_evt(enum gpio_signal signal);
+static void usba_oc_interrupt(enum gpio_signal signal);
 static void ppc_interrupt(enum gpio_signal signal);
 static void board_connect_c0_sbu(enum gpio_signal s);
 
@@ -74,6 +76,19 @@ static void usb1_evt(enum gpio_signal signal)
 	task_set_event(TASK_ID_USB_CHG_P1, USB_CHG_EVENT_BC12, 0);
 }
 
+static void usba_oc_deferred(void)
+{
+	/* Use next number after all USB-C ports to indicate the USB-A port */
+	board_overcurrent_event(CONFIG_USB_PD_PORT_MAX_COUNT,
+				!gpio_get_level(GPIO_USB_A0_OC_ODL));
+}
+DECLARE_DEFERRED(usba_oc_deferred);
+
+static void usba_oc_interrupt(enum gpio_signal signal)
+{
+	hook_call_deferred(&usba_oc_deferred_data, 0);
+}
+
 static void ppc_interrupt(enum gpio_signal signal)
 {
 	switch (signal) {
@@ -274,6 +289,9 @@ static void board_init(void)
 	gpio_enable_interrupt(GPIO_USB_C0_BC12_INT_L);
 	gpio_enable_interrupt(GPIO_USB_C1_BC12_INT_L);
 
+	/* Enable USB-A overcurrent interrupt */
+	gpio_enable_interrupt(GPIO_USB_A0_OC_ODL);
+
 	/* Enable interrupt for BMI160 sensor */
 	gpio_enable_interrupt(GPIO_ACCEL_GYRO_INT_L);
 
diff --git a/board/trogdor/gpio.inc b/board/trogdor/gpio.inc
index 4d6ea0fcf2..8534e001f8 100644
--- a/board/trogdor/gpio.inc
+++ b/board/trogdor/gpio.inc
@@ -8,7 +8,7 @@
 /* Declare symbolic names for all the GPIOs that we care about.
  * Note: Those with interrupt handlers must be declared first. */
 
-/* USB-C interrupts */
+/* USB interrupts */
 GPIO_INT(USB_C0_PD_INT_ODL,    PIN(E, 0), GPIO_INT_FALLING, tcpc_alert_event)  /* Interrupt from port-0 TCPC */
 GPIO_INT(USB_C1_PD_INT_ODL,    PIN(F, 5), GPIO_INT_FALLING, tcpc_alert_event)  /* Interrupt from port-1 TCPC */
 GPIO_INT(USB_C0_SWCTL_INT_ODL, PIN(0, 3), GPIO_INT_FALLING, ppc_interrupt)  /* Interrupt from port-0 PPC */
@@ -20,6 +20,8 @@ GPIO_INT(USB_C1_BC12_INT_L,    PIN(8, 2), GPIO_INT_FALLING | GPIO_PULL_UP, usb1_
 GPIO_INT(USB_C0_BC12_INT_L,    PIN(6, 1), GPIO_INT_FALLING, usb0_evt)  /* Interrupt from port-0 BC1.2 */
 GPIO_INT(USB_C1_BC12_INT_L,    PIN(8, 2), GPIO_INT_FALLING, usb1_evt)  /* Interrupt from port-1 BC1.2 */
 #endif /* BOARD_REV */
+GPIO_INT(USB_A0_OC_ODL,        PIN(D, 1), GPIO_INT_BOTH | GPIO_PULL_UP, usba_oc_interrupt)
+
 /* System interrupts */
 GPIO_INT(ACOK_OD,           PIN(0, 0), GPIO_INT_BOTH, extpower_interrupt)  /* ACOK */
 GPIO_INT(CCD_MODE_ODL,      PIN(E, 3), GPIO_INT_FALLING, board_connect_c0_sbu)  /* Case Closed Debug Mode */
@@ -89,7 +91,6 @@ GPIO(USB_C1_VBUS_DET_L,     PIN(8, 3), GPIO_INPUT)     /* Deprecated BC1.2 VBUS
 /* USB-A */
 GPIO(EN_USB_A_5V,           PIN(8, 6), GPIO_OUT_LOW)
 GPIO(USB_A_CDP_ILIM_EN_L,   PIN(7, 5), GPIO_OUT_HIGH)  /* H:CDP, L:SDP. Only one USB-A port, always CDP */
-GPIO(USB_A0_OC_ODL,         PIN(D, 1), GPIO_ODR_HIGH)
 
 /* LEDs */
 GPIO(EC_CHG_LED_Y_C0,       PIN(C, 3), GPIO_OUT_LOW)