[PATCH v2 15/15] platform/chrome: cros_ec_proto: return 0 on getting wake mask success

[Tzung-Bi Shih <tzungbi@kernel.org>]

cros_ec_get_host_event_wake_mask() used to return value from
send_command() which is number of bytes for input payload on success
(i.e. sizeof(struct ec_response_host_event_mask)).

However, the callers don't need to know how many bytes are available.

- Fix cros_ec_get_host_event_wake_mask() to return 0 on success;
  negative integers on error.

- Add a Kunit test for guarding if send_command() returns 0 in
  get_host_event_wake_mask().

Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
---
Changes from v1:
- Return 0 on success; otherwise, negative intergers.

 drivers/platform/chrome/cros_ec_proto.c      |  23 ++--
 drivers/platform/chrome/cros_ec_proto_test.c | 128 +++++++++++++++++++
 2 files changed, 142 insertions(+), 9 deletions(-)

diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c
index 9d96ed16244f..04c852aa790b 100644
--- a/drivers/platform/chrome/cros_ec_proto.c
+++ b/drivers/platform/chrome/cros_ec_proto.c
@@ -256,18 +256,23 @@ static int cros_ec_get_host_event_wake_mask(struct cros_ec_device *ec_dev, uint3
 	msg->insize = sizeof(*r);
 
 	ret = send_command(ec_dev, msg);
-	if (ret >= 0) {
-		mapped = cros_ec_map_error(msg->result);
-		if (mapped) {
-			ret = mapped;
-			goto exit;
-		}
+	if (ret < 0)
+		goto exit;
+
+	mapped = cros_ec_map_error(msg->result);
+	if (mapped) {
+		ret = mapped;
+		goto exit;
 	}
-	if (ret > 0) {
-		r = (struct ec_response_host_event_mask *)msg->data;
-		*mask = r->mask;
+
+	if (ret == 0) {
+		ret = -EPROTO;
+		goto exit;
 	}
 
+	r = (struct ec_response_host_event_mask *)msg->data;
+	*mask = r->mask;
+	ret = 0;
 exit:
 	kfree(msg);
 	return ret;
diff --git a/drivers/platform/chrome/cros_ec_proto_test.c b/drivers/platform/chrome/cros_ec_proto_test.c
index af69410f2978..3ee0de337d53 100644
--- a/drivers/platform/chrome/cros_ec_proto_test.c
+++ b/drivers/platform/chrome/cros_ec_proto_test.c
@@ -1406,6 +1406,133 @@ static void cros_ec_proto_test_query_all_default_wake_mask_return_error(struct k
 	}
 }
 
+static void cros_ec_proto_test_query_all_default_wake_mask_return0(struct kunit *test)
+{
+	struct cros_ec_proto_test_priv *priv = test->priv;
+	struct cros_ec_device *ec_dev = &priv->ec_dev;
+	struct ec_xfer_mock *mock;
+	int ret;
+
+	/* Set some garbage bytes. */
+	ec_dev->host_event_wake_mask = U32_MAX;
+
+	/* For cros_ec_get_proto_info() without passthru. */
+	{
+		struct ec_response_get_protocol_info *data;
+
+		mock = cros_kunit_ec_xfer_mock_add(test, sizeof(*data));
+		KUNIT_ASSERT_PTR_NE(test, mock, NULL);
+
+		/*
+		 * Although it doesn't check the value, provides valid sizes so that
+		 * cros_ec_query_all() allocates din and dout correctly.
+		 */
+		data = (struct ec_response_get_protocol_info *)mock->o_data;
+		data->max_request_packet_size = 0xbe;
+		data->max_response_packet_size = 0xef;
+	}
+
+	/* For cros_ec_get_proto_info() with passthru. */
+	{
+		mock = cros_kunit_ec_xfer_mock_addx(test, 0, EC_RES_INVALID_COMMAND, 0);
+		KUNIT_ASSERT_PTR_NE(test, mock, NULL);
+	}
+
+	/* For cros_ec_get_host_command_version_mask() for MKBP. */
+	{
+		mock = cros_kunit_ec_xfer_mock_add(test, 0);
+		KUNIT_ASSERT_PTR_NE(test, mock, NULL);
+	}
+
+	/* For cros_ec_get_host_command_version_mask() for host sleep v1. */
+	{
+		mock = cros_kunit_ec_xfer_mock_add(test, 0);
+		KUNIT_ASSERT_PTR_NE(test, mock, NULL);
+	}
+
+	/* For get_host_event_wake_mask(). */
+	{
+		mock = cros_kunit_ec_xfer_mock_add(test, 0);
+		KUNIT_ASSERT_PTR_NE(test, mock, NULL);
+	}
+
+	cros_ec_proto_test_query_all_pretest(test);
+	ret = cros_ec_query_all(ec_dev);
+	KUNIT_EXPECT_EQ(test, ret, 0);
+
+	/* For cros_ec_get_proto_info() without passthru. */
+	{
+		mock = cros_kunit_ec_xfer_mock_next();
+		KUNIT_EXPECT_PTR_NE(test, mock, NULL);
+
+		KUNIT_EXPECT_EQ(test, mock->msg.version, 0);
+		KUNIT_EXPECT_EQ(test, mock->msg.command, EC_CMD_GET_PROTOCOL_INFO);
+		KUNIT_EXPECT_EQ(test, mock->msg.insize,
+				sizeof(struct ec_response_get_protocol_info));
+		KUNIT_EXPECT_EQ(test, mock->msg.outsize, 0);
+	}
+
+	/* For cros_ec_get_proto_info() with passthru. */
+	{
+		mock = cros_kunit_ec_xfer_mock_next();
+		KUNIT_EXPECT_PTR_NE(test, mock, NULL);
+
+		KUNIT_EXPECT_EQ(test, mock->msg.version, 0);
+		KUNIT_EXPECT_EQ(test, mock->msg.command,
+				EC_CMD_PASSTHRU_OFFSET(CROS_EC_DEV_PD_INDEX) |
+				EC_CMD_GET_PROTOCOL_INFO);
+		KUNIT_EXPECT_EQ(test, mock->msg.insize,
+				sizeof(struct ec_response_get_protocol_info));
+		KUNIT_EXPECT_EQ(test, mock->msg.outsize, 0);
+	}
+
+	/* For cros_ec_get_host_command_version_mask() for MKBP. */
+	{
+		mock = cros_kunit_ec_xfer_mock_next();
+		KUNIT_EXPECT_PTR_NE(test, mock, NULL);
+
+		KUNIT_EXPECT_EQ(test, mock->msg.version, 0);
+		KUNIT_EXPECT_EQ(test, mock->msg.command, EC_CMD_GET_CMD_VERSIONS);
+		KUNIT_EXPECT_EQ(test, mock->msg.insize,
+				sizeof(struct ec_response_get_cmd_versions));
+		KUNIT_EXPECT_EQ(test, mock->msg.outsize, sizeof(struct ec_params_get_cmd_versions));
+	}
+
+	/* For cros_ec_get_host_command_version_mask() for host sleep v1. */
+	{
+		mock = cros_kunit_ec_xfer_mock_next();
+		KUNIT_EXPECT_PTR_NE(test, mock, NULL);
+
+		KUNIT_EXPECT_EQ(test, mock->msg.version, 0);
+		KUNIT_EXPECT_EQ(test, mock->msg.command, EC_CMD_GET_CMD_VERSIONS);
+		KUNIT_EXPECT_EQ(test, mock->msg.insize,
+				sizeof(struct ec_response_get_cmd_versions));
+		KUNIT_EXPECT_EQ(test, mock->msg.outsize, sizeof(struct ec_params_get_cmd_versions));
+	}
+
+	/* For get_host_event_wake_mask(). */
+	{
+		u32 mask;
+
+		mock = cros_kunit_ec_xfer_mock_next();
+		KUNIT_EXPECT_PTR_NE(test, mock, NULL);
+
+		KUNIT_EXPECT_EQ(test, mock->msg.version, 0);
+		KUNIT_EXPECT_EQ(test, mock->msg.command, EC_CMD_HOST_EVENT_GET_WAKE_MASK);
+		KUNIT_EXPECT_EQ(test, mock->msg.insize, sizeof(struct ec_response_host_event_mask));
+		KUNIT_EXPECT_EQ(test, mock->msg.outsize, 0);
+
+		mask = ec_dev->host_event_wake_mask;
+		KUNIT_EXPECT_EQ(test, mask & EC_HOST_EVENT_MASK(EC_HOST_EVENT_LID_CLOSED), 0);
+		KUNIT_EXPECT_EQ(test, mask & EC_HOST_EVENT_MASK(EC_HOST_EVENT_AC_DISCONNECTED), 0);
+		KUNIT_EXPECT_EQ(test, mask & EC_HOST_EVENT_MASK(EC_HOST_EVENT_BATTERY_LOW), 0);
+		KUNIT_EXPECT_EQ(test, mask & EC_HOST_EVENT_MASK(EC_HOST_EVENT_BATTERY_CRITICAL), 0);
+		KUNIT_EXPECT_EQ(test, mask & EC_HOST_EVENT_MASK(EC_HOST_EVENT_BATTERY), 0);
+		KUNIT_EXPECT_EQ(test, mask & EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU), 0);
+		KUNIT_EXPECT_EQ(test, mask & EC_HOST_EVENT_MASK(EC_HOST_EVENT_BATTERY_STATUS), 0);
+	}
+}
+
 static void cros_ec_proto_test_release(struct device *dev)
 {
 }
@@ -1471,6 +1598,7 @@ static struct kunit_case cros_ec_proto_test_cases[] = {
 	KUNIT_CASE(cros_ec_proto_test_query_all_no_host_sleep),
 	KUNIT_CASE(cros_ec_proto_test_query_all_no_host_sleep_return0),
 	KUNIT_CASE(cros_ec_proto_test_query_all_default_wake_mask_return_error),
+	KUNIT_CASE(cros_ec_proto_test_query_all_default_wake_mask_return0),
 	{}
 };
 
-- 
2.36.1.255.ge46751e96f-goog