rambi: Accelerometer driver for kxcj9.

Added accelerometer driver for kxcj9 accelerometers. Currently
the accelerometers aren't being used by anything, but there are
console commands, accelwrite and accelread, to perform transactions.

BUG=none
BRANCH=rambi
TEST=Used EC console commands to test that accelerometers respond
and data looks reasonable.

Original-Change-Id: I6ddcf04ec278adeacb148c19b10c3c296b467954
Signed-off-by: Alec Berg <alecaberg@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/184693
Reviewed-by: Randall Spangler <rspangler@chromium.org>
(cherry picked from commit 5e1d2052b034b2400b98b2126243e01397a2ce56)

Conflicts:
	board/clapper/board.c
	board/clapper/board.h
	board/glimmer/board.c
	board/glimmer/board.h

Change-Id: If8744ddc3273fc08e29830adfd068dc302dd120a
Signed-off-by: Alec Berg <alecaberg@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/187432
Reviewed-by: Randall Spangler <rspangler@chromium.org>

5 files changed, 424 insertions, 0 deletions

diff --git a/driver/accel_kxcj9.c b/driver/accel_kxcj9.c
new file mode 100644
index 0000000000..83967eb873
--- /dev/null
+++ b/driver/accel_kxcj9.c
@@ -0,0 +1,249 @@
+/* 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.
+ */
+
+/* KXCJ9 gsensor module for Chrome EC */
+
+#include "accelerometer.h"
+#include "common.h"
+#include "console.h"
+#include "driver/accel_kxcj9.h"
+#include "gpio.h"
+#include "i2c.h"
+#include "util.h"
+
+/* Range of the accelerometers: 2G, 4G, or 8G. */
+static int sensor_range[ACCEL_COUNT] = {KXCJ9_GSEL_2G, KXCJ9_GSEL_2G};
+
+/* Resolution: KXCJ9_RES_12BIT or KXCJ9_RES_12BIT. */
+static int sensor_resolution[ACCEL_COUNT] = {KXCJ9_RES_12BIT, KXCJ9_RES_12BIT};
+
+/* Output data rate: KXCJ9_OSA_* ranges from 0.781Hz to 1600Hz. */
+static int sensor_datarate[ACCEL_COUNT] = {KXCJ9_OSA_12_50HZ,
+						KXCJ9_OSA_12_50HZ};
+
+#ifdef CONFIG_CMD_ACCELS
+/**
+ * Read register from accelerometer.
+ */
+static int raw_read8(const int addr, const int reg, int *data_ptr)
+{
+	return i2c_read8(I2C_PORT_ACCEL, addr, reg, data_ptr);
+}
+#endif /* CONFIG_CMD_ACCELS */
+
+/**
+ * Write register from accelerometer.
+ */
+static int raw_write8(const int addr, const int reg, int data)
+{
+	return i2c_write8(I2C_PORT_ACCEL, addr, reg, data);
+}
+
+
+int accel_write_range(const enum accel_id id, const int range)
+{
+	int ret;
+
+	/* Check for valid id. */
+	if (id < 0 || id >= ACCEL_COUNT)
+		return EC_ERROR_INVAL;
+
+	/*
+	 * Verify that the input range is valid. Note that we currently
+	 * don't support the 8G with 14-bit resolution mode.
+	 */
+	if (range != KXCJ9_GSEL_2G && range != KXCJ9_GSEL_4G &&
+		range != KXCJ9_GSEL_8G)
+		return EC_ERROR_INVAL;
+
+	ret = raw_write8(accel_addr[id],  KXCJ9_CTRL1,
+			KXCJ9_CTRL1_PC1 | sensor_resolution[id] | range);
+
+	/* If successfully written, then save the range. */
+	if (ret == EC_SUCCESS)
+		sensor_range[id] = range;
+
+	return ret;
+}
+
+int accel_write_resolution(const enum accel_id id, const int res)
+{
+	int ret;
+
+	/* Check for valid id. */
+	if (id < 0 || id >= ACCEL_COUNT)
+		return EC_ERROR_INVAL;
+
+	/* Check that resolution input is valid. */
+	if (res != KXCJ9_RES_12BIT && res != KXCJ9_RES_8BIT)
+		return EC_ERROR_INVAL;
+
+	ret = raw_write8(accel_addr[id],  KXCJ9_CTRL1,
+			KXCJ9_CTRL1_PC1 | res | sensor_range[id]);
+
+	/* If successfully written, then save the range. */
+	if (ret == EC_SUCCESS)
+		sensor_resolution[id] = res;
+
+	return ret;
+}
+
+int accel_write_datarate(const enum accel_id id, const int rate)
+{
+	int ret;
+
+	/* Check for valid id. */
+	if (id < 0 || id >= ACCEL_COUNT)
+		return EC_ERROR_INVAL;
+
+	/* Check that rate input is valid. */
+	if (rate < KXCJ9_OSA_12_50HZ || rate > KXCJ9_OSA_6_250HZ)
+		return EC_ERROR_INVAL;
+
+	/* Set output data rate. */
+	ret = raw_write8(accel_addr[id],  KXCJ9_DATA_CTRL, rate);
+
+	/* If successfully written, then save the range. */
+	if (ret == EC_SUCCESS)
+		sensor_datarate[id] = rate;
+
+	return ret;
+}
+
+int accel_read(enum accel_id id, int *x_acc, int *y_acc, int *z_acc)
+{
+	uint8_t acc[6];
+	uint8_t reg = KXCJ9_XOUT_L;
+	int ret, multiplier;
+
+	/* Check for valid id. */
+	if (id < 0 || id >= ACCEL_COUNT)
+		return EC_ERROR_INVAL;
+
+	/* Read 6 bytes starting at KXCJ9_XOUT_L. */
+	ret = i2c_xfer(I2C_PORT_ACCEL, accel_addr[id], &reg, 1, acc, 6,
+			I2C_XFER_SINGLE);
+
+	if (ret != EC_SUCCESS)
+		return ret;
+
+	/* Determine multiplier based on stored range. */
+	switch (sensor_range[id]) {
+	case KXCJ9_GSEL_2G:
+		multiplier = 1;
+		break;
+	case KXCJ9_GSEL_4G:
+		multiplier = 2;
+		break;
+	case KXCJ9_GSEL_8G:
+		multiplier = 4;
+		break;
+	default:
+		return EC_ERROR_UNKNOWN;
+	}
+
+	/*
+	 * Convert acceleration to a signed 12-bit number. Note, based on
+	 * the order of the registers:
+	 *
+	 * acc[0] = KXCJ9_XOUT_L
+	 * acc[1] = KXCJ9_XOUT_H
+	 * acc[2] = KXCJ9_YOUT_L
+	 * acc[3] = KXCJ9_YOUT_H
+	 * acc[4] = KXCJ9_ZOUT_L
+	 * acc[5] = KXCJ9_ZOUT_H
+	 */
+	*x_acc = multiplier * (((int8_t)acc[1]) << 4) | (acc[0] >> 4);
+	*y_acc = multiplier * (((int8_t)acc[3]) << 4) | (acc[2] >> 4);
+	*z_acc = multiplier * (((int8_t)acc[5]) << 4) | (acc[4] >> 4);
+
+	return EC_SUCCESS;
+}
+
+int accel_init(enum accel_id id)
+{
+	int ret = EC_SUCCESS;
+
+	/* Check for valid id. */
+	if (id < 0 || id >= ACCEL_COUNT)
+		return EC_ERROR_INVAL;
+
+	/* Enable accelerometer, 12-bit resolution mode, +/- 2G range.*/
+	ret |= raw_write8(accel_addr[id],  KXCJ9_CTRL1,
+			KXCJ9_CTRL1_PC1 | sensor_resolution[id] |
+			sensor_range[id]);
+
+	/* Set output data rate. */
+	ret |= raw_write8(accel_addr[id],  KXCJ9_DATA_CTRL,
+			sensor_datarate[id]);
+
+	return ret;
+}
+
+
+
+/*****************************************************************************/
+/* Console commands */
+
+#ifdef CONFIG_CMD_ACCELS
+static int command_read_accelerometer(int argc, char **argv)
+{
+	char *e;
+	int addr, reg, data;
+
+	if (argc != 3)
+		return EC_ERROR_PARAM_COUNT;
+
+	/* First argument is address. */
+	addr = strtoi(argv[1], &e, 0);
+	if (*e)
+		return EC_ERROR_PARAM1;
+
+	/* Second argument is register offset. */
+	reg = strtoi(argv[2], &e, 0);
+	if (*e)
+		return EC_ERROR_PARAM2;
+
+	raw_read8(addr, reg, &data);
+
+	ccprintf("0x%02x\n", data);
+
+	return EC_SUCCESS;
+}
+DECLARE_CONSOLE_COMMAND(accelread, command_read_accelerometer,
+	"addr reg",
+	"Read from accelerometer at slave address addr", NULL);
+
+static int command_write_accelerometer(int argc, char **argv)
+{
+	char *e;
+	int addr, reg, data;
+
+	if (argc != 4)
+		return EC_ERROR_PARAM_COUNT;
+
+	/* First argument is address. */
+	addr = strtoi(argv[1], &e, 0);
+	if (*e)
+		return EC_ERROR_PARAM1;
+
+	/* Second argument is register offset. */
+	reg = strtoi(argv[2], &e, 0);
+	if (*e)
+		return EC_ERROR_PARAM2;
+
+	/* Third argument is data. */
+	data = strtoi(argv[3], &e, 0);
+	if (*e)
+		return EC_ERROR_PARAM3;
+
+	raw_write8(addr, reg, data);
+
+	return EC_SUCCESS;
+}
+DECLARE_CONSOLE_COMMAND(accelwrite, command_write_accelerometer,
+	"addr reg data",
+	"Write to accelerometer at slave address addr", NULL);
+#endif /* CONFIG_CMD_ACCELS */
diff --git a/driver/accel_kxcj9.h b/driver/accel_kxcj9.h
new file mode 100644
index 0000000000..9451421be5
--- /dev/null
+++ b/driver/accel_kxcj9.h
@@ -0,0 +1,132 @@
+/* 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.
+ */
+
+/* KXCJ9 gsensor module for Chrome EC */
+
+#ifndef __CROS_EC_ACCEL_KXCJ9_H
+#define __CROS_EC_ACCEL_KXCJ9_H
+
+/*
+ * 7-bit address is 000111Xb. Where 'X' is determined
+ * by the voltage on the ADDR pin.
+ */
+#define KXCJ9_ADDR0		0x1c
+#define KXCJ9_ADDR1		0x1e
+
+/* Chip-specific registers */
+#define KXCJ9_XOUT_L		0x06
+#define KXCJ9_XOUT_H		0x07
+#define KXCJ9_YOUT_L		0x08
+#define KXCJ9_YOUT_H		0x09
+#define KXCJ9_ZOUT_L		0x0a
+#define KXCJ9_ZOUT_H		0x0b
+#define KXCJ9_DCST_RESP		0x0c
+#define KXCJ9_WHOAMI		0x0f
+#define KXCJ9_INT_SRC1		0x16
+#define KXCJ9_INT_SRC2		0x17
+#define KXCJ9_STATUS		0x18
+#define KXCJ9_INT_REL		0x1a
+#define KXCJ9_CTRL1		0x1b
+#define KXCJ9_CTRL2		0x1d
+#define KXCJ9_INT_CTRL1		0x1e
+#define KXCJ9_INT_CTRL2		0x1f
+#define KXCJ9_DATA_CTRL		0x21
+#define KXCJ9_WAKEUP_TIMER	0x29
+#define KXCJ9_SELF_TEST		0x3a
+#define KXCJ9_WAKEUP_THRESHOLD	0x6a
+
+#define KXCJ9_INT_SRC1_WUFS	(1 << 1)
+#define KXCJ9_INT_SRC1_DRDY	(1 << 4)
+
+#define KXCJ9_INT_SRC2_ZPWU	(1 << 0)
+#define KXCJ9_INT_SRC2_ZNWU	(1 << 1)
+#define KXCJ9_INT_SRC2_YPWU	(1 << 2)
+#define KXCJ9_INT_SRC2_YNWU	(1 << 3)
+#define KXCJ9_INT_SRC2_XPWU	(1 << 4)
+#define KXCJ9_INT_SRC2_XNWU	(1 << 5)
+
+#define KXCJ9_STATUS_INT	(1 << 4)
+
+#define KXCJ9_CTRL1_WUFE	(1 << 1)
+#define KXCJ9_CTRL1_DRDYE	(1 << 5)
+#define KXCJ9_CTRL1_PC1		(1 << 7)
+
+#define KXCJ9_GSEL_2G		(0 << 3)
+#define KXCJ9_GSEL_4G		(1 << 3)
+#define KXCJ9_GSEL_8G		(2 << 3)
+#define KXCJ9_GSEL_8G_14BIT	(3 << 3)
+
+#define KXCJ9_RES_8BIT		(0 << 6)
+#define KXCJ9_RES_12BIT		(1 << 6)
+
+#define KXCJ9_CTRL2_OWUF	(7 << 0)
+#define KXCJ9_CTRL2_DCST	(1 << 4)
+#define KXCJ9_CTRL2_SRST	(1 << 7)
+
+#define KXCJ9_OWUF_0_781HZ	0
+#define KXCJ9_OWUF_1_563HZ	1
+#define KXCJ9_OWUF_3_125HZ	2
+#define KXCJ9_OWUF_6_250HZ	3
+#define KXCJ9_OWUF_12_50HZ	4
+#define KXCJ9_OWUF_25_00HZ	5
+#define KXCJ9_OWUF_50_00HZ	6
+#define KXCJ9_OWUF_100_0HZ	7
+
+#define KXCJ9_INT_CTRL1_IEL		(1 << 3)
+#define KXCJ9_INT_CTRL1_IEA		(1 << 4)
+#define KXCJ9_INT_CTRL1_IEN		(1 << 5)
+
+#define KXCJ9_INT_CTRL2_ZPWUE		(1 << 0)
+#define KXCJ9_INT_CTRL2_ZNWUE		(1 << 1)
+#define KXCJ9_INT_CTRL2_YPWUE		(1 << 2)
+#define KXCJ9_INT_CTRL2_YNWUE		(1 << 3)
+#define KXCJ9_INT_CTRL2_XPWUE		(1 << 4)
+#define KXCJ9_INT_CTRL2_XNWUE		(1 << 5)
+
+#define KXCJ9_OSA_0_781HZ	8
+#define KXCJ9_OSA_1_563HZ	9
+#define KXCJ9_OSA_3_125HZ	0xa
+#define KXCJ9_OSA_6_250HZ	0xb
+#define KXCJ9_OSA_12_50HZ	0
+#define KXCJ9_OSA_25_00HZ	1
+#define KXCJ9_OSA_50_00HZ	2
+#define KXCJ9_OSA_100_0HZ	3
+#define KXCJ9_OSA_200_0HZ	4
+#define KXCJ9_OSA_400_0HZ	5
+#define KXCJ9_OSA_800_0HZ	6
+#define KXCJ9_OSA_1600_HZ	7
+
+
+/**
+ * Write the accelerometer range.
+ *
+ * @param id Target accelerometer
+ * @param range Range (KXCJ9_GSEL_*).
+ *
+ * @return EC_SUCCESS if successful, non-zero if error.
+ */
+int accel_write_range(const enum accel_id id, const int range);
+
+/**
+ * Write the accelerometer resolution.
+ *
+ * @param id Target accelerometer
+ * @param range Resolution (KXCJ9_RES_*).
+ *
+ * @return EC_SUCCESS if successful, non-zero if error.
+ */
+int accel_write_resolution(const enum accel_id id, const int res);
+
+/**
+ * Write the accelerometer data rate.
+ *
+ * @param id Target accelerometer
+ * @param range Data rate (KXCJ9_OSA_*).
+ *
+ * @return EC_SUCCESS if successful, non-zero if error.
+ */
+int accel_write_datarate(const enum accel_id id, const int rate);
+
+#endif /* __CROS_EC_ACCEL_KXCJ9_H */
diff --git a/driver/build.mk b/driver/build.mk
index f981b6942c..f9c31b143b 100644
--- a/driver/build.mk
+++ b/driver/build.mk
@@ -6,6 +6,9 @@
 # Drivers for off-chip devices
 #
 
+# Accelerometers
+driver-$(CONFIG_ACCEL_KXCJ9)+=accel_kxcj9.o
+
 # ALS drivers
 driver-$(CONFIG_ALS_ISL29035)+=als_isl29035.o
 
diff --git a/include/accelerometer.h b/include/accelerometer.h
new file mode 100644
index 0000000000..48d61ac3ab
--- /dev/null
+++ b/include/accelerometer.h
@@ -0,0 +1,36 @@
+/* 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.
+ */
+
+/* This array must be defined in board.c. */
+extern const int accel_addr[];
+
+/* This enum must be defined in board.h. */
+enum accel_id;
+
+/* Number of counts from accelerometer that represents 1G acceleration. */
+#define ACCEL_G  1024
+
+/**
+ * Read all three accelerations of an accelerometer. Note that all three
+ * accelerations come back in counts, where ACCEL_G can be used to convert
+ * counts to engineering units.
+ *
+ * @param id Target accelerometer
+ * @param x_acc Pointer to store X-axis acceleration (in counts).
+ * @param y_acc Pointer to store Y-axis acceleration (in counts).
+ * @param z_acc Pointer to store Z-axis acceleration (in counts).
+ *
+ * @return EC_SUCCESS if successful, non-zero if error.
+ */
+int accel_read(enum accel_id id, int *x_acc, int *y_acc, int *z_acc);
+
+/**
+ * Initiailze accelerometers.
+ *
+ * @param id Target accelerometer
+ *
+ * @return EC_SUCCESS if successful, non-zero if error.
+ */
+int accel_init(enum accel_id id);
diff --git a/include/config.h b/include/config.h
index 479a68e61a..114e6e982f 100644
--- a/include/config.h
+++ b/include/config.h
@@ -36,6 +36,9 @@
  * BOARD_*, CHIP_*, and CHIP_FAMILY_*.
  */
 
+/* Specify type of accelerometers attached. */
+#undef CONFIG_ACCEL_KXCJ9
+
 /* Compile chip support for analog-to-digital convertor */
 #undef CONFIG_ADC
 
@@ -234,6 +237,7 @@
  * console.
  */
 
+#undef CONFIG_CMD_ACCELS
 #undef CONFIG_CMD_BATDEBUG
 #undef CONFIG_CMD_CLOCKGATES
 #undef CONFIG_CMD_COMXTEST