rambi: Add motion sense task to track motion

Added motion sense task to Clapper and Glimmer. This task samples
the accelerometers and calculate a lid angle. Note that as
the machine is rotated towards the hinge angle aligning
with gravity, the lid calculation becomes less trustworthy.

Added a math_util file to hold various mathematical functions
useful for calculating lid angle that may be helpful in other
places.

For each board with accelerometers we need to define some
orientation specific data in board.c. There is a calibration
procedure through the EC console that can be enabled by
defining CONFIG_ACCEL_CALIBRATE. The calibration procedure can
help determine the orientation data required.

For debugging purposes there is a console command to regularly
print to the EC console the accelerometer data and derived lid
angle. The console command can be enabled by defining
CONFIG_CMD_LID_ANGLE.

BUG=none
Original-BUG=chrome-os-partner:24703
BRANCH=rambi
TEST=Ran the calibration procedure on a Glimmer unit, and then
rotated the machine in space. Verified that the lid angle
calculated roughly matched actual lid angle.

Original-Change-Id: I63a5e384b7f6b628b4ea01de49843355fb8d6ebe
Signed-off-by: Alec Berg <alecaberg@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/184783
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Signed-off-by: Alec Berg <alecaberg@chromium.org>
(cherry picked from commit efb07945a5159fa0e7a746c666b2519ebdca9c22)

Conflicts:
	board/clapper/board.c
	board/clapper/ec.tasklist
	board/glimmer/board.c
	board/glimmer/ec.tasklist

Change-Id: Ibc492ef5c11e7084e87f01338c4d7775f9a08c18
Signed-off-by: Alec Berg <alecaberg@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/187433
Reviewed-by: Randall Spangler <rspangler@chromium.org>

1 files changed, 71 insertions, 0 deletions

diff --git a/include/motion_sense.h b/include/motion_sense.h
new file mode 100644
index 0000000000..a6aa79b5bf
--- /dev/null
+++ b/include/motion_sense.h
@@ -0,0 +1,71 @@
+/* Copyright (c) 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.
+ */
+
+/* Header for motion_sense.c */
+
+#ifndef __CROS_EC_MOTION_SENSE_H
+#define __CROS_EC_MOTION_SENSE_H
+
+#include "math_util.h"
+
+/**
+ * This structure defines all of the data needed to specify the orientation
+ * of the base and lid accelerometers in order to calculate the lid angle.
+ */
+struct accel_orientation {
+	/*
+	 * Rotation matrix to rotate the lid sensor into the same reference
+	 * frame as the base sensor.
+	 */
+	matrix_3x3_t rot_align;
+
+	/* Rotation matrix to rotate positive 90 degrees around the hinge. */
+	matrix_3x3_t rot_hinge_90;
+
+	/*
+	 * Rotation matrix to rotate 180 degrees around the hinge. The value
+	 * here should be rot_hinge_90 ^ 2.
+	 */
+	matrix_3x3_t rot_hinge_180;
+
+	/* Vector pointing along hinge axis. */
+	vector_3_t hinge_axis;
+};
+
+/* Link global structure for orientation. This must be defined in board.c. */
+extern
+#ifndef CONFIG_ACCEL_CALIBRATE
+const
+#endif
+struct accel_orientation acc_orient;
+
+
+/**
+ * Get last calculated lid angle.
+ *
+ * @return lid angle in degrees in range [-180, 180].
+ */
+int motion_get_lid_angle(void);
+
+
+#ifdef CONFIG_ACCEL_CALIBRATE
+/**
+ * Get the last measured lid acceleration vector.
+ *
+ * @param v Pointer to location to store vector.
+ * @param adjusted If false use the raw vector, if true use the adjusted vector.
+ */
+void motion_get_accel_lid(vector_3_t *v, int adjusted);
+
+/**
+ * Get the last measured base acceleration vector.
+ *
+ * @param v Pointer to location to store vector.
+ */
+void motion_get_accel_base(vector_3_t *v);
+#endif
+
+
+#endif /* __CROS_EC_MOTION_SENSE_H */