MKBP event signalling implementation

This implements a new API for EC modules to define MKBP event sources
and send MKBP event to the AP. Also, a new host command
EC_CMD_GET_NEXT_EVENT is added for the AP to query the pending MKBP
events. Each event type may have custom event data sent along with the
event.

BRANCH=None
BUG=chrome-os-partner:33194
TEST=Enable MKBP event on Ryu. Set a host event from EC console, run
'ectool nextevent', and see MKBP event 0x01 (HOST_EVENT) and the set
host event.

Signed-off-by: Vic Yang <victoryang@chromium.org>
Change-Id: I28a1b7e826bcc102bbe39016c9bb3e37d125664c
Reviewed-on: https://chromium-review.googlesource.com/224905
Reviewed-by: Randall Spangler <rspangler@chromium.org>

1 files changed, 37 insertions, 0 deletions

diff --git a/include/mkbp_event.h b/include/mkbp_event.h
new file mode 100644
index 0000000000..8da19fc02d
--- /dev/null
+++ b/include/mkbp_event.h
@@ -0,0 +1,37 @@
+/* Copyright 2014 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ * Event handling in MKBP keyboard protocol
+ */
+
+#ifndef __CROS_EC_MKBP_EVENT_H
+#define __CROS_EC_MKBP_EVENT_H
+
+/*
+ * Sends an event to the AP.
+ *
+ * When this is called, the event data must be ready for query.  Otherwise,
+ * when the AP queries the event, an error is returned and the event is lost.
+ *
+ * @param event_type  One of EC_MKBP_EVENT_*.
+ */
+void mkbp_send_event(uint8_t event_type);
+
+/*
+ * The struct to store the event source definition.  The get_data routine is
+ * responsible for returning the event data when queried by the AP.  The
+ * parameter 'data' points to where the event data needs to be stored, and
+ * the size of the event data should be returned.
+ */
+struct mkbp_event_source {
+	uint8_t event_type;
+	int (*get_data)(uint8_t *data);
+};
+
+#define DECLARE_EVENT_SOURCE(type, func)                   \
+	const struct mkbp_event_source __evt_src_##type \
+	__attribute__((section(".rodata.evtsrcs")))        \
+		 = {type, func}
+
+#endif  /* __CROS_EC_MKBP_EVENT_H */