mfd: cros_ec: Add MKBP event support

Newer revisions of the ChromeOS EC add more events besides the keyboard
ones. So handle interrupts in the MFD driver and let consumers register
for notifications for the events they might care.

To keep backward compatibility, if the EC doesn't support MKBP event, we
fall back to the old MKBP key matrix host command.

Cc: Randall Spangler <rspangler@chromium.org>
Cc: Vincent Palatin <vpalatin@chromium.org>
Cc: Benson Leung <bleung@chromium.org>
Signed-off-by: Vic Yang <victoryang@google.com>
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Tested-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

1 files changed, 34 insertions, 0 deletions

diff --git a/include/linux/mfd/cros_ec_commands.h b/include/linux/mfd/cros_ec_commands.h
index 7e7a8d4b4551..76728ff37d01 100644
--- a/include/linux/mfd/cros_ec_commands.h
+++ b/include/linux/mfd/cros_ec_commands.h
@@ -1793,6 +1793,40 @@ struct ec_result_keyscan_seq_ctrl {
 	};
 } __packed;
 
+/*
+ * Command for retrieving the next pending MKBP event from the EC device
+ *
+ * The device replies with UNAVAILABLE if there aren't any pending events.
+ */
+#define EC_CMD_GET_NEXT_EVENT 0x67
+
+enum ec_mkbp_event {
+	/* Keyboard matrix changed. The event data is the new matrix state. */
+	EC_MKBP_EVENT_KEY_MATRIX = 0,
+
+	/* New host event. The event data is 4 bytes of host event flags. */
+	EC_MKBP_EVENT_HOST_EVENT = 1,
+
+	/* New Sensor FIFO data. The event data is fifo_info structure. */
+	EC_MKBP_EVENT_SENSOR_FIFO = 2,
+
+	/* Number of MKBP events */
+	EC_MKBP_EVENT_COUNT,
+};
+
+union ec_response_get_next_data {
+	uint8_t   key_matrix[13];
+
+	/* Unaligned */
+	uint32_t  host_event;
+} __packed;
+
+struct ec_response_get_next_event {
+	uint8_t event_type;
+	/* Followed by event data if any */
+	union ec_response_get_next_data data;
+} __packed;
+
 /*****************************************************************************/
 /* Temperature sensor commands */