ec/google/wilco: Add mailbox helper functions

Add helper functions that make it more convenient to send and receive
the most common types of commands to the Wilco embedded controller.

Change-Id: I9cee1a3b2f9d507f6ecdfae9f4a34ba59056cb91
Signed-off-by: Duncan Laurie <dlaurie@google.com>
Reviewed-on: https://review.coreboot.org/29114
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/ec/google/wilco/ec.h

@@ -44,4 +44,77 @@ int wilco_ec_mailbox(enum wilco_ec_msg_type type, uint8_t command,
 		     const void *request_data, size_t request_size,
 		     void *response_data, size_t response_size);
 
+/**
+ * wilco_ec_send
+ *
+ * Send a basic EC command with a one byte parameter with no
+ * returned data;
+ *
+ * @command: Command to execute
+ * @param:   Command parameter to send
+ *
+ * @return negative error code on failure
+ */
+static inline int wilco_ec_send(uint8_t command, uint8_t param)
+{
+	return wilco_ec_mailbox(WILCO_EC_MSG_DEFAULT, command,
+				&param, sizeof(param), NULL, 0);
+}
+
+/**
+ * wilco_ec_send_noargs
+ *
+ * Send a basic EC command with no parameters and no returned data.
+ *
+ * @command: Command to execute
+ *
+ * @return negative error code on failure
+ */
+static inline int wilco_ec_send_noargs(uint8_t command)
+{
+	return wilco_ec_mailbox(WILCO_EC_MSG_DEFAULT, command,
+				NULL, 0, NULL, 0);
+}
+
+/**
+ * wilco_ec_sendrecv
+ *
+ * Send a basic EC command with a one byte parameter, ignoring the
+ * first byte of returned data to match the common behavior.
+ * The maximum response size is 31 due to the ignored byte.
+ *
+ * @command: Command to execute
+ * @param:   Command parameter to send
+ * @data:    Response data buffer
+ * @size:    Number of bytes in response data buffer (max 31)
+ *
+ * @return number of bytes received, negative error code on failure
+ */
+static inline int wilco_ec_sendrecv(uint8_t command, uint8_t param,
+				    void *data, size_t size)
+{
+	return wilco_ec_mailbox(WILCO_EC_MSG_DEFAULT, command,
+				&param, sizeof(param), data, size);
+}
+
+/**
+ * wilco_ec_sendrecv_noargs
+ *
+ * Send a basic EC command with no parameters, ignoring the
+ * first byte of returned data to match the common behavior.
+ * The maximum response size is 31 due to the ignored byte.
+ *
+ * @command: Command to execute
+ * @data:    Response data buffer
+ * @size:    Number of bytes in response data buffer (max 31)
+ *
+ * @return number of bytes received, negative error code on failure
+ */
+static inline int wilco_ec_sendrecv_noargs(uint8_t command,
+					   void *data, size_t size)
+{
+	return wilco_ec_mailbox(WILCO_EC_MSG_DEFAULT, command,
+				NULL, 0, data, size);
+}
+
 #endif /* EC_GOOGLE_WILCO_EC_H */