samus: add ability for PD MCU to send host event to AP

Add host event for PD up to AP. The PD toggles a gpio line to
EC causing an interrupt on EC. The EC then sends host command
down to PD MCU to get its status. There is a new status bit for
PD host event, so when EC see's the PD host event status bit,
it sends a PD host event to the AP.

There is currently only one host event for PD to AP.

BUG=chrome-os-partner:31361
BRANCH=none
TEST=added PD console command pdevent, which initiates the host
event. when sent, verified on EC that it sets the correct host
event bit using hostevent console command

Change-Id: If1a59a3232e2f9a49f272c6dee5319254d87b9a9
Signed-off-by: Alec Berg <alecaberg@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/213371
Reviewed-by: Randall Spangler <rspangler@chromium.org>

3 files changed, 25 insertions, 1 deletions

diff --git a/board/samus_pd/usb_pd_policy.c b/board/samus_pd/usb_pd_policy.c
index 867a020dd6..7b56d12435 100644
--- a/board/samus_pd/usb_pd_policy.c
+++ b/board/samus_pd/usb_pd_policy.c
@@ -3,6 +3,7 @@
  * found in the LICENSE file.
  */
 
+#include "atomic.h"
 #include "common.h"
 #include "console.h"
 #include "gpio.h"
@@ -194,6 +195,18 @@ DECLARE_CONSOLE_COMMAND(ecint, command_ec_int,
 			"Toggle EC interrupt line",
 			NULL);
 
+static int command_pd_host_event(int argc, char **argv)
+{
+	atomic_or(&(pd_status.status), PD_STATUS_HOST_EVENT);
+	pd_send_ec_int();
+
+	return EC_SUCCESS;
+}
+DECLARE_CONSOLE_COMMAND(pdevent, command_pd_host_event,
+			"",
+			"Send PD host event",
+			NULL);
+
 /****************************************************************************/
 /* Host commands */
 static int ec_status_host_cmd(struct host_cmd_handler_args *args)
@@ -205,6 +218,9 @@ static int ec_status_host_cmd(struct host_cmd_handler_args *args)
 
 	*r = pd_status;
 
+	/* Clear host event */
+	atomic_clear(&(pd_status.status), PD_STATUS_HOST_EVENT);
+
 	args->response_size = sizeof(*r);
 
 	return EC_RES_SUCCESS;
diff --git a/common/host_command_pd.c b/common/host_command_pd.c
index 5f57c83305..467dc07dd7 100644
--- a/common/host_command_pd.c
+++ b/common/host_command_pd.c
@@ -54,6 +54,10 @@ static void pd_exchange_status(void)
 					CONFIG_CHARGER_INPUT_CURRENT));
 	if (rv < 0)
 		CPRINTS("Failed to set input current limit from PD MCU");
+
+	/* If PD is signalling host event, then pass it up to AP */
+	if (pd_status.status | PD_STATUS_HOST_EVENT)
+		host_set_single_event(EC_HOST_EVENT_PD_MCU);
 }
 
 void pd_command_task(void)
diff --git a/include/ec_commands.h b/include/ec_commands.h
index 83bca00c84..6b065accdc 100644
--- a/include/ec_commands.h
+++ b/include/ec_commands.h
@@ -271,6 +271,9 @@ enum host_event_code {
 	/* Hang detect logic detected a hang and warm rebooted the AP */
 	EC_HOST_EVENT_HANG_REBOOT = 21,
 
+	/* PD MCU triggering host event */
+	EC_HOST_EVENT_PD_MCU = 22,
+
 	/*
 	 * The high bit of the event mask is not used as a host event code.  If
 	 * it reads back as set, then the entire event mask should be
@@ -2497,8 +2500,9 @@ struct ec_params_pd_status {
 } __packed;
 
 /* Status of PD being sent back to EC */
+#define PD_STATUS_HOST_EVENT (1 << 0)
 struct ec_response_pd_status {
-	int8_t status;        /* PD MCU status */
+	uint32_t status;      /* PD MCU status */
 	uint32_t curr_lim_ma; /* input current limit */
 } __packed;