PCHG: Get SOC proactively when device is detected

This patch makes PCHG send CHG_CTRL_CHARGING_INFO_CMD when a stylus
is detected. This will allow the EC to report 'full' to the host
even if charging doesn't start (because the stylus is already
charged).

BUG=b:179390065,b:173235954
BRANCH=trogdor
TEST=CoachZ. Re-attach charged stylus and verify PCHG_STATE_FULL
is reported.

Change-Id: Id8578e2d3d21294fb08a21933f12ecee7f2bd062
Signed-off-by: Daisuke Nojiri <dnojiri@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2691729
Reviewed-by: Vincent Palatin <vpalatin@chromium.org>

3 files changed, 42 insertions, 5 deletions

diff --git a/common/peripheral_charger.c b/common/peripheral_charger.c
index 85910d4c76..cb9a6e1f3e 100644
--- a/common/peripheral_charger.c
+++ b/common/peripheral_charger.c
@@ -83,6 +83,9 @@ static enum pchg_state pchg_initialize(struct pchg *ctx, enum pchg_state state)
 		CPRINTS("ERR: Failed to initialize");
 	}
 
+	ctx->battery_percent = 0;
+	ctx->error = 0;
+
 	return state;
 }
 
@@ -159,6 +162,11 @@ static enum pchg_state pchg_state_enabled(struct pchg *ctx)
 		state = PCHG_STATE_INITIALIZED;
 		break;
 	case PCHG_EVENT_DEVICE_DETECTED:
+		/*
+		 * Proactively query SOC in case charging info won't be sent
+		 * because device is already charged.
+		 */
+		ctx->cfg->drv->get_soc(ctx);
 		state = PCHG_STATE_DETECTED;
 		break;
 	case PCHG_EVENT_CHARGE_STARTED:
@@ -195,6 +203,7 @@ static enum pchg_state pchg_state_detected(struct pchg *ctx)
 		state = PCHG_STATE_CHARGING;
 		break;
 	case PCHG_EVENT_DEVICE_LOST:
+		ctx->battery_percent = 0;
 		state = PCHG_STATE_ENABLED;
 		break;
 	case PCHG_EVENT_CHARGE_ERROR:
@@ -231,6 +240,7 @@ static enum pchg_state pchg_state_charging(struct pchg *ctx)
 		CPRINTS("Battery %d%%", ctx->battery_percent);
 		break;
 	case PCHG_EVENT_DEVICE_LOST:
+		ctx->battery_percent = 0;
 		state = PCHG_STATE_ENABLED;
 		break;
 	case PCHG_EVENT_CHARGE_ERROR:
@@ -444,8 +454,9 @@ static int cc_pchg(int argc, char **argv)
 	ctx = &pchgs[port];
 
 	if (argc == 2) {
-		ccprintf("P%d STATE_%s EVENT_%s\n", port,
-			 _text_state(ctx->state), _text_event(ctx->event));
+		ccprintf("P%d STATE_%s EVENT_%s SOC=%d%%\n", port,
+			 _text_state(ctx->state), _text_event(ctx->event),
+			 ctx->battery_percent);
 		return EC_SUCCESS;
 	}
 
diff --git a/driver/nfc/ctn730.c b/driver/nfc/ctn730.c
index c8be10d297..8e5dd2ea20 100644
--- a/driver/nfc/ctn730.c
+++ b/driver/nfc/ctn730.c
@@ -90,6 +90,8 @@ static const int _detection_interval_ms = 100;
 #define WLC_HOST_CTRL_DUMP_STATUS_CMD_SIZE	1
 
 /* WLC_CHG_CTRL_CHARGING_INFO constants */
+#define WLC_CHG_CTRL_CHARGING_INFO_CMD_SIZE	0
+#define WLC_CHG_CTRL_CHARGING_INFO_RSP_SIZE	2
 #define WLC_CHG_CTRL_CHARGING_INFO_EVT_SIZE	5
 
 /* Status Codes */
@@ -313,12 +315,13 @@ static int _process_payload_response(struct pchg *ctx, struct ctn730_msg *res)
 	if (IS_ENABLED(CTN730_DEBUG))
 		CPRINTS("Payload: %ph", HEX_BUF(buf, len));
 
+	ctx->event = PCHG_EVENT_NONE;
+
 	switch (res->instruction) {
 	case WLC_HOST_CTRL_RESET:
 		if (len != WLC_HOST_CTRL_RESET_RSP_SIZE
 				|| buf[0] != WLC_HOST_STATUS_OK)
 			return EC_ERROR_UNKNOWN;
-		ctx->event = PCHG_EVENT_NONE;
 		break;
 	case WLC_CHG_CTRL_ENABLE:
 		if (len != WLC_CHG_CTRL_ENABLE_RSP_SIZE
@@ -330,11 +333,15 @@ static int _process_payload_response(struct pchg *ctx, struct ctn730_msg *res)
 		if (len != WLC_CHG_CTRL_DISABLE_RSP_SIZE
 				|| buf[0] != WLC_HOST_STATUS_OK)
 			return EC_ERROR_UNKNOWN;
-		ctx->event = PCHG_EVENT_NONE;
+		break;
+	case WLC_CHG_CTRL_CHARGING_INFO:
+		if (len != WLC_CHG_CTRL_CHARGING_INFO_RSP_SIZE
+				|| buf[0] != WLC_HOST_STATUS_OK)
+			return EC_ERROR_UNKNOWN;
+		ctx->battery_percent = buf[1];
 		break;
 	default:
 		CPRINTS("Received unknown response (%d)", res->instruction);
-		ctx->event = PCHG_EVENT_NONE;
 		break;
 	}
 
@@ -453,6 +460,22 @@ static int ctn730_get_event(struct pchg *ctx)
 	return EC_ERROR_UNKNOWN;
 }
 
+static int ctn730_get_soc(struct pchg *ctx)
+{
+	struct ctn730_msg cmd;
+	int rv;
+
+	cmd.message_type = CTN730_MESSAGE_TYPE_COMMAND;
+	cmd.instruction = WLC_CHG_CTRL_CHARGING_INFO;
+	cmd.length = WLC_CHG_CTRL_CHARGING_INFO_CMD_SIZE;
+
+	rv = _send_command(ctx, &cmd);
+	if (rv)
+		return rv;
+
+	return EC_SUCCESS;
+}
+
 /**
  * Send command in blocking loop
  *
@@ -519,6 +542,7 @@ const struct pchg_drv ctn730_drv = {
 	.init = ctn730_init,
 	.enable = ctn730_enable,
 	.get_event = ctn730_get_event,
+	.get_soc = ctn730_get_soc,
 };
 
 static int cc_ctn730(int argc, char **argv)
diff --git a/include/peripheral_charger.h b/include/peripheral_charger.h
index 2ede2c6f2c..62b1b0ac01 100644
--- a/include/peripheral_charger.h
+++ b/include/peripheral_charger.h
@@ -146,6 +146,8 @@ struct pchg_drv {
 	int (*enable)(struct pchg *ctx, bool enable);
 	/* Get event info. */
 	int (*get_event)(struct pchg *ctx);
+	/* Get battery level. */
+	int (*get_soc)(struct pchg *ctx);
 };
 
 /**