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[v5] add support for Freescale's MMA8653FC 10 bit accelerometer

Message ID 1426936150-2439-1-git-send-email-martink@posteo.de (mailing list archive)
State New, archived
Headers show

Commit Message

Martin Kepplinger-Novakovic March 21, 2015, 11:09 a.m. UTC
From: Martin Kepplinger <martin.kepplinger@theobroma-systems.com>

The MMA8653FC is a low-power, three-axis, capacitive micromachined
accelerometer with 10 bits of resolution with flexible user-programmable
options.

Embedded interrupt functions enable overall power savings, by relieving the
host processor from continuously polling data, for example using the poll()
system call.

The device can be configured to generate wake-up interrupt signals from any
combination of the configurable embedded functions, enabling the MMA8653FC
to monitor events while remaining in a low-power mode during periods of
inactivity.

This driver provides devicetree properties to program the device's behaviour
and a simple, tested and documented sysfs interface. The data sheet and more
information is available on Freescale's website.

Signed-off-by: Martin Kepplinger <martin.kepplinger@theobroma-systems.com>
Signed-off-by: Christoph Muellner <christoph.muellner@theobroma-systems.com>
---

Sorry, I forgot the Kconfig integration into drivers/staging.
This applies and builds.

 drivers/staging/Kconfig               |   2 +
 drivers/staging/mma8653fc/Kconfig     |  10 +
 drivers/staging/mma8653fc/Makefile    |   1 +
 drivers/staging/mma8653fc/TODO        | 146 ++++++
 drivers/staging/mma8653fc/mma8653fc.c | 864 ++++++++++++++++++++++++++++++++++
 5 files changed, 1023 insertions(+)
 create mode 100644 drivers/staging/mma8653fc/Kconfig
 create mode 100644 drivers/staging/mma8653fc/Makefile
 create mode 100644 drivers/staging/mma8653fc/TODO
 create mode 100644 drivers/staging/mma8653fc/mma8653fc.c
diff mbox

Patch

diff --git a/drivers/staging/Kconfig b/drivers/staging/Kconfig
index bfacf69..834d949 100644
--- a/drivers/staging/Kconfig
+++ b/drivers/staging/Kconfig
@@ -112,4 +112,6 @@  source "drivers/staging/i2o/Kconfig"
 
 source "drivers/staging/fsl-mc/Kconfig"
 
+source "drivers/staging/mma8653fc/Kconfig"
+
 endif # STAGING
diff --git a/drivers/staging/mma8653fc/Kconfig b/drivers/staging/mma8653fc/Kconfig
new file mode 100644
index 0000000..988451b
--- /dev/null
+++ b/drivers/staging/mma8653fc/Kconfig
@@ -0,0 +1,10 @@ 
+config MMA8653FC
+        tristate "MMA8653FC - Freescale's 3-Axis, 10-bit Digital Accelerometer"
+        depends on I2C
+        default n
+        help
+          Say Y here if you want to support Freescale's MMA8653FC Accelerometer
+          through I2C interface.
+
+          To compile this driver as a module, choose M here: the
+          module will be called mma8653fc.
diff --git a/drivers/staging/mma8653fc/Makefile b/drivers/staging/mma8653fc/Makefile
new file mode 100644
index 0000000..9a245a3
--- /dev/null
+++ b/drivers/staging/mma8653fc/Makefile
@@ -0,0 +1 @@ 
+obj-$(CONFIG_MMA8653FC)         += mma8653fc.o
diff --git a/drivers/staging/mma8653fc/TODO b/drivers/staging/mma8653fc/TODO
new file mode 100644
index 0000000..0a31225
--- /dev/null
+++ b/drivers/staging/mma8653fc/TODO
@@ -0,0 +1,146 @@ 
+- move to IIO device API. The current DT/sysfs interface is documented below
+
+Documentation/ABI/testing/...
+-----------------------------
+What:		/sys/bus/i2c/drivers/mma8653fc/*/standby
+Date:		March 2015
+Contact:	Martin Kepplinger <martin.kepplinger@theobroma-systems.com>
+Description:
+		Write 0 to this in order to turn on the device, and 1 to turn
+		it off. Read to see if it is turned on or off.
+
+
+What:		/sys/bus/i2c/drivers/mma8653fc/*/currentmode
+Date:		March 2015
+Contact:	Martin Kepplinger <martin.kepplinger@theobroma-systems.com>
+Description:
+		Reading this provides the current state of the device, read
+		directly from a register. This can be "standby", "wake" or
+		"sleep".
+
+
+What:		/sys/bus/i2c/drivers/mma8653fc/*/position
+Date:		March 2015
+Contact:	Martin Kepplinger <martin.kepplinger@theobroma-systems.com>
+Description:
+		Read only. Without interrupts enabled gets current position
+		values by reading. Poll "position" with interrupt conditions
+		set, to get notified; see Documentation/.../fsl,mma8653fc.txt
+
+		position file format:
+		"x y z [landscape/portrait status] [front/back status]"
+
+		x y z values:
+			in mg
+		landscape/portrait status char:
+			r	landscape right
+			d	portrait down
+			u	portrait up
+			l	landscape left
+		front/back status char:
+			f	front facing
+			b	back facing
+
+
+Documentation/devicetree/bindings/...
+-------------------------------------
+Required properties:
+- compatible
+	"fsl,mma8653fc"
+- reg
+	I2C address
+
+Optional properties:
+
+- interrupt-parent
+	a phandle for the interrupt controller (see
+	Documentation/devicetree/bindings/interrupt-controller/interrupts.txt)
+- interrupts
+	interrupt line to which the chip is connected (active low)
+- int1
+	set to use interrupt line 1, default is line 2
+	the interrupt sources can be routed to one of the two lines
+- ir-freefall-motion-x
+	activate freefall/motion interrupts on x axis
+- ir-freefall-motion-y
+	activate freefall/motion interrupts on y axis
+- ir-freefall-motion-z
+	activate freefall/motion interrupts on z axis
+- irq-threshold
+	0 < value < 8000: threshold for motion interrupts in mg
+- ir-landscape-portrait
+	activate landscape/portrait interrupts
+- ir-auto-wake
+	activate wake/sleep change interrupts
+- ir-data-ready:
+	activate data-ready interrupts
+	Interrupt events can be activated in any combination.
+- dynamic-range
+	2, 4, or 8: dynamic measurement range in g, default: 2
+	In ±2 g mode, sensitivity = 256 counts/g.
+	In ±4 g mode, sensitivity = 128 counts/g.
+	In ±8 g mode, sensitivity = 64 counts/g.
+- auto-wake-sleep
+	auto sleep mode (lower frequency)
+- motion-mode
+	use motion mode instead of freefall mode (trigger if >threshold).
+	per default an interrupt occurs if motion values fall below the
+	value set in "threshold" and therefore can detect free fall on the
+	vertical axis (depending on the position of the device).
+	Setting this values inverts the behaviour and an interrupt occurs
+	above the threshold value, so usually activate horizontal axis in
+	this case.
+
+- x-offset
+	0 < value < 500: calibration offset in mg
+	The offset correction values are used to realign the Zero-g position
+	of the X, Y, and Z-axis after the device is mounted on a board.
+	this value has an offset of 250 itself:
+	0 is -250mg, 250 is 0 mg, 500 is 250mg
+- y-offset
+	see x-offset
+- z-offset
+	see x-offset
+
+Example 1:
+for a device laying on flat ground to recognize acceleration over 100mg.
+x-axis is calibrated to +10mg. Adapt interrupt line to your device.
+
+mma8653fc@1d {
+		compatible = "fsl,mma8653fc";
+		interrupt-parent = <&gpio1>;
+		interrupts = <5 0>;
+		reg = <0x1d>;
+
+		dynamic-range = <2>;
+		motion-mode;
+		ir-freefall-motion-x;
+		ir-freefall-motion-y;
+		irq-threshold = <100>;
+		x-offset = <160>;
+};
+
+Example 2:
+for a device mounted on a wall with y being the vertical axis. This recognizes
+y-acceleration below 800mg, so free fall or changing the orientation of the
+device (y not being the vertical axis and having ~1000mg anymore).
+
+mma8653fc@1d {
+		compatible = "fsl,mma8653fc";
+		interrupt-parent = <&gpio1>;
+		interrupts = <5 0>;
+		reg = <0x1d>;
+
+		dynamic-range = <2>;
+		ir-freefall-motion-y;
+		irq-threshold = <800>;
+};
+
+Example 3:
+minimal example. lets users read current acceleration values. No polling
+is available.
+
+mma8653fc@1d {
+		compatible = "fsl,mma8653fc";
+		reg = <0x1d>;
+};
diff --git a/drivers/staging/mma8653fc/mma8653fc.c b/drivers/staging/mma8653fc/mma8653fc.c
new file mode 100644
index 0000000..4bd7f99
--- /dev/null
+++ b/drivers/staging/mma8653fc/mma8653fc.c
@@ -0,0 +1,864 @@ 
+/*
+ * mma8653fc.c - Support for Freescale MMA8653FC 3-axis 10-bit accelerometer
+ *
+ * Copyright (c) 2014 Theobroma Systems Design and Consulting GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/types.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+
+#define DRV_NAME	"mma8653fc"
+#define MMA8653FC_DEVICE_ID	0x5a
+
+#define MMA8653FC_STATUS	0x00
+
+#define ZYXOW_MASK	0x80
+#define ZYXDR		0x08
+
+#define MMA8653FC_WHO_AM_I	0x0d
+
+#define MMA8653FC_SYSMOD	0x0b
+#define STATE_STANDBY	0x00
+#define STATE_WAKE	0x01
+#define STATE_SLEEP	0x02
+
+#define MMA8450_STATUS_ZXYDR	0x08
+
+/*
+ * 10 bit output data registers
+ * MSB: 7:0 bits 9:2 of data word
+ * LSB: 7:6 bits 1:0 of data word
+ */
+#define MMA8653FC_OUT_X_MSB	0x01
+#define MMA8653FC_OUT_X_LSB	0x02
+#define MMA8653FC_OUT_Y_MSB	0x03
+#define MMA8653FC_OUT_Y_LSB	0x04
+#define MMA8653FC_OUT_Z_MSB	0x05
+#define MMA8653FC_OUT_Z_LSB	0x06
+
+/*
+ * Portrait/Landscape Status
+ */
+#define MMA8653FC_PL_STATUS	0x10
+
+#define NEWLP		0x80
+#define LAPO_HIGH	0x04
+#define LAPO_LOW	0x02
+#define BAFRO		0x01
+
+/*
+ * Portrait/Landscape Configuration
+ */
+#define MMA8653FC_PL_CFG	0x11
+
+#define PL_EN		(1 << 6)
+
+/*
+ * Data calibration registers
+ */
+#define MMA8653FC_OFF_X		0x2f
+#define MMA8653FC_OFF_Y		0x30
+#define MMA8653FC_OFF_Z		0x31
+
+/* 0 to 500 for dts, but -250 to 250 in mg */
+#define DEFAULT_OFF	250
+
+/*
+ * bits 1:0 dynamic range
+ * 00 +/- 2g
+ * 01 +/- 4g
+ * 10 +/- 8g
+ *
+ * HPF_Out bit 4 - data high pass or low pass filtered
+ */
+#define MMA8653FC_XYZ_DATA_CFG	0x0e
+
+#define RANGE_MASK	0x03
+#define RANGE2G		0x00
+#define RANGE4G		0x01
+#define RANGE8G		0x02
+/* values for calculation */
+#define SHIFT_2G	8
+#define INCR_2G		128
+#define SHIFT_4G	7
+#define INCR_4G		64
+#define SHIFT_8G	6
+#define INCR_8G		32
+#define DYN_RANGE_2G	2
+#define DYN_RANGE_4G	4
+#define DYN_RANGE_8G	8
+
+/*
+ * System Control Reg 1
+ */
+#define MMA8653FC_CTRL_REG1	0x2a
+
+#define ACTIVE_BIT	(1 << 0)
+#define ODR_MASK	0x38
+#define ODR_DEFAULT	0x20 /* 50 Hz */
+#define ASLP_RATE_MASK	0xc0
+#define ASLP_RATE_DEFAULT 0x80 /* 6.25 Hz */
+
+/*
+ * Sys Control Reg 2
+ *
+ * auto-sleep enable, software reset
+ */
+#define MMA8653FC_CTRL_REG2	0x2b
+
+#define SLPE		(1 << 2)
+#define SELFTEST	(1 << 7)
+#define SOFT_RESET	(1 << 6)
+
+/*
+ * Interrupt Source
+ */
+#define MMA8653FC_INT_SOURCE	0x0c
+
+#define SRC_ASLP	(1 << 7)
+#define SRC_LNDPRT	(1 << 4)
+#define SRC_FF_MT	(1 << 2)
+#define SRC_DRDY	(1 << 0)
+
+/*
+ * Interrupt Control Register
+ *
+ * default: active low
+ * default push-pull, not open-drain
+ */
+#define MMA8653FC_CTRL_REG3	0x2c
+
+#define WAKE_LNDPRT	(1 << 5)
+#define WAKE_FF_MT	(1 << 3)
+#define IPOL		(1 << 1)
+#define PP_OD		(1 << 0)
+
+/*
+ * Interrupt Enable Register
+ */
+#define MMA8653FC_CTRL_REG4	0x2d
+
+#define INT_EN_ASLP	(1 << 7)
+#define INT_EN_LNDPRT	(1 << 4)
+#define INT_EN_FF_MT	(1 << 2)
+#define INT_EN_DRDY	(1 << 0)
+
+/*
+ * Interrupt Configuration Register
+ * bit value 0 ... INT2 (default)
+ * bit value 1 ... INT1
+ */
+#define MMA8653FC_CTRL_REG5	0x2e
+
+#define INT_CFG_ASLP	(1 << 7)
+#define INT_CFG_LNDPRT	(1 << 4)
+#define INT_CFG_FF_MT	(1 << 2)
+#define INT_CFG_DRDY	(1 << 0)
+
+/*
+ * Freefall / Motion Configuration Register
+ *
+ * Event Latch enable/disable, motion or freefall mode
+ * and event flag enable per axis
+ */
+#define MMA8653FC_FF_MT_CFG	0x15
+
+#define FF_MT_CFG_ELE	(1 << 7)
+#define FF_MT_CFG_OAE	(1 << 6)
+#define FF_MT_CFG_ZEFE	(1 << 5)
+#define FF_MT_CFG_YEFE	(1 << 4)
+#define FF_MT_CFG_XEFE	(1 << 3)
+
+/*
+ * Freefall / Motion Source Register
+ */
+#define MMA8653FC_FF_MT_SRC	0x16
+
+/*
+ * Freefall / Motion Threshold Register
+ *
+ * define motion threshold
+ * 0.063 g/LSB, 127 counts(0x7f) (7 bit from LSB)
+ * range: 0.063g - 8g
+ */
+#define MMA8653FC_FF_MT_THS	0x17
+
+struct axis_triple {
+	s16 x;
+	s16 y;
+	s16 z;
+};
+
+struct mma8653fc_pdata {
+	s8 x_axis_offset;
+	s8 y_axis_offset;
+	s8 z_axis_offset;
+	bool auto_wake_sleep;
+	u32 range;
+	bool int1;
+	bool motion_mode;
+	u8 freefall_motion_thr;
+	bool int_src_data_ready;
+	bool int_src_ff_mt_x;
+	bool int_src_ff_mt_y;
+	bool int_src_ff_mt_z;
+	bool int_src_lndprt;
+	bool int_src_aslp;
+};
+
+struct mma8653fc {
+	struct i2c_client *client;
+	struct mutex mutex;
+	struct mma8653fc_pdata pdata;
+	struct axis_triple saved;
+	char orientation;
+	char bafro;
+	bool standby;
+	int irq;
+	unsigned int_mask;
+	u8 (*read)(struct mma8653fc *, unsigned char);
+	void (*write)(struct mma8653fc *, unsigned char, unsigned char);
+};
+
+/* defaults */
+static const struct mma8653fc_pdata mma8653fc_default_init = {
+	.range = 2,
+	.x_axis_offset = DEFAULT_OFF,
+	.y_axis_offset = DEFAULT_OFF,
+	.z_axis_offset = DEFAULT_OFF,
+	.auto_wake_sleep = false,
+	.int1 = false,
+	.motion_mode = false,
+	.freefall_motion_thr = 5,
+	.int_src_data_ready = false,
+	.int_src_ff_mt_x = false,
+	.int_src_ff_mt_y = false,
+	.int_src_ff_mt_z = false,
+	.int_src_lndprt = false,
+	.int_src_aslp = false,
+};
+
+static void mma8653fc_get_triple(struct mma8653fc *mma)
+{
+	u8 buf[6];
+	u8 status;
+
+	buf[0] = 0;
+
+	status = mma->read(mma, MMA8653FC_STATUS);
+	if (status & ZYXOW_MASK)
+		dev_dbg(&mma->client->dev, "previous read not completed\n");
+
+	buf[0] = mma->read(mma, MMA8653FC_OUT_X_MSB);
+	buf[1] = mma->read(mma, MMA8653FC_OUT_X_LSB);
+	buf[2] = mma->read(mma, MMA8653FC_OUT_Y_MSB);
+	buf[3] = mma->read(mma, MMA8653FC_OUT_Y_LSB);
+	buf[4] = mma->read(mma, MMA8653FC_OUT_Z_MSB);
+	buf[5] = mma->read(mma, MMA8653FC_OUT_Z_LSB);
+
+	mutex_lock(&mma->mutex);
+	/* move from registers to s16 */
+	mma->saved.x = (buf[1] | (buf[0] << 8)) >> 6;
+	mma->saved.y = (buf[3] | (buf[2] << 8)) >> 6;
+	mma->saved.z = (buf[5] | (buf[4] << 8)) >> 6;
+	mma->saved.x = sign_extend32(mma->saved.x, 9);
+	mma->saved.y = sign_extend32(mma->saved.y, 9);
+	mma->saved.z = sign_extend32(mma->saved.z, 9);
+
+	/* calc g, see data sheet and application note */
+	switch (mma->pdata.range) {
+	case DYN_RANGE_2G:
+		mma->saved.x = le16_to_cpu((1000 * mma->saved.x +
+					    INCR_2G) >> SHIFT_2G);
+		mma->saved.y = le16_to_cpu((1000 * mma->saved.y +
+					   INCR_2G) >> SHIFT_2G);
+		mma->saved.z = le16_to_cpu((1000 * mma->saved.z +
+					   INCR_2G) >> SHIFT_2G);
+		break;
+	case DYN_RANGE_4G:
+		mma->saved.x = le16_to_cpu((1000 * mma->saved.x +
+					   INCR_4G) >> SHIFT_4G);
+		mma->saved.y = le16_to_cpu((1000 * mma->saved.y +
+					   INCR_4G) >> SHIFT_4G);
+		mma->saved.z = le16_to_cpu((1000 * mma->saved.z +
+					   INCR_4G) >> SHIFT_4G);
+		break;
+	case DYN_RANGE_8G:
+		mma->saved.x = le16_to_cpu((1000 * mma->saved.x +
+					   INCR_8G) >> SHIFT_8G);
+		mma->saved.y = le16_to_cpu((1000 * mma->saved.y +
+					   INCR_8G) >> SHIFT_8G);
+		mma->saved.z = le16_to_cpu((1000 * mma->saved.z +
+					   INCR_8G) >> SHIFT_8G);
+		break;
+	default:
+		dev_err(&mma->client->dev, "internal data corrupt\n");
+	}
+	mutex_unlock(&mma->mutex);
+}
+
+static void mma8653fc_get_orientation(struct mma8653fc *mma, u8 byte)
+{
+	if ((byte & LAPO_HIGH) && !(LAPO_LOW))
+		mma->orientation = 'r'; /* landscape right */
+	if (!(byte & LAPO_HIGH) && (byte & LAPO_LOW))
+		mma->orientation = 'd'; /* portrait down */
+	if (!(byte & LAPO_HIGH) && !(byte & LAPO_LOW))
+		mma->orientation = 'u'; /* portrait up */
+	if ((byte & LAPO_HIGH) && (byte & LAPO_LOW))
+		mma->orientation = 'l'; /* landscape left */
+
+	if (byte & BAFRO)
+		mma->bafro = 'b'; /* back facing */
+	else
+		mma->bafro = 'f'; /* front facing */
+}
+
+static irqreturn_t mma8653fc_irq(int irq, void *handle)
+{
+	struct mma8653fc *mma = handle;
+	u8 int_src;
+	u8 byte;
+
+	int_src = mma->read(mma, MMA8653FC_INT_SOURCE);
+	if (int_src & SRC_DRDY)
+		/* data ready handle */
+	if (int_src & SRC_FF_MT) {
+		/* freefall/motion change handle */
+		dev_dbg(&mma->client->dev,
+			"freefall or motion change\n");
+		byte = mma->read(mma, MMA8653FC_FF_MT_SRC);
+	}
+	if (int_src & SRC_LNDPRT) {
+		/* landscape/portrait change handle */
+		dev_dbg(&mma->client->dev,
+			"landscape / portrait change\n");
+		byte = mma->read(mma, MMA8653FC_PL_STATUS);
+		mma8653fc_get_orientation(mma, byte);
+	}
+	if (int_src & SRC_ASLP)
+		/* autosleep change handle */
+	mma8653fc_get_triple(mma);
+
+	sysfs_notify(&mma->client->dev.kobj, NULL, "position");
+
+	return IRQ_HANDLED;
+}
+
+static void __mma8653fc_enable(struct mma8653fc *mma)
+{
+	u8 byte;
+
+	byte = mma->read(mma, MMA8653FC_CTRL_REG1);
+	mma->write(mma, MMA8653FC_CTRL_REG1, byte | ACTIVE_BIT);
+}
+
+static void __mma8653fc_disable(struct mma8653fc *mma)
+{
+	u8 byte;
+
+	byte = mma->read(mma, MMA8653FC_CTRL_REG1);
+	mma->write(mma, MMA8653FC_CTRL_REG1, byte & ~ACTIVE_BIT);
+}
+
+static ssize_t mma8653fc_standby_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct mma8653fc *mma = i2c_get_clientdata(client);
+
+	return scnprintf(buf, PAGE_SIZE, "%u\n", mma->standby);
+}
+
+static ssize_t mma8653fc_standby_store(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf, size_t count)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct mma8653fc *mma = i2c_get_clientdata(client);
+	unsigned int val;
+	int error;
+
+	error = kstrtouint(buf, 10, &val);
+	if (error)
+		return error;
+
+	mutex_lock(&mma->mutex);
+
+	if (val) {
+		if (!mma->standby)
+			__mma8653fc_disable(mma);
+	} else {
+		if (mma->standby)
+			__mma8653fc_enable(mma);
+	}
+
+	mma->standby = !!val;
+
+	mutex_unlock(&mma->mutex);
+
+	return count;
+}
+
+static DEVICE_ATTR(standby, 0664, mma8653fc_standby_show,
+				  mma8653fc_standby_store);
+
+static ssize_t mma8653fc_currentmode_show(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct mma8653fc *mma = i2c_get_clientdata(client);
+	ssize_t count;
+	u8 byte;
+
+	byte = mma->read(mma, MMA8653FC_SYSMOD);
+	if (byte < 0)
+		return byte;
+
+	switch (byte) {
+	case STATE_STANDBY:
+		count = scnprintf(buf, PAGE_SIZE, "standby\n");
+		break;
+	case STATE_WAKE:
+		count = scnprintf(buf, PAGE_SIZE, "wake\n");
+		break;
+	case STATE_SLEEP:
+		count = scnprintf(buf, PAGE_SIZE, "sleep\n");
+		break;
+	default:
+		count = scnprintf(buf, PAGE_SIZE, "unknown\n");
+	}
+	return count;
+}
+static DEVICE_ATTR(currentmode, S_IRUGO, mma8653fc_currentmode_show, NULL);
+
+static ssize_t mma8653fc_position_show(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct mma8653fc *mma = i2c_get_clientdata(client);
+	ssize_t count;
+	u8 byte;
+
+	if (!mma->irq) {
+		byte = mma->read(mma, MMA8653FC_PL_STATUS);
+		if (byte & NEWLP)
+			mma8653fc_get_orientation(mma, byte);
+
+		byte = mma->read(mma, MMA8653FC_STATUS);
+		if (byte & ZYXDR)
+			mma8653fc_get_triple(mma);
+
+		msleep(20);
+		dev_dbg(&client->dev, "data polled\n");
+	}
+	mutex_lock(&mma->mutex);
+	count = scnprintf(buf, PAGE_SIZE, "%d %d %d %c %c\n",
+			mma->saved.x, mma->saved.y, mma->saved.z,
+			mma->orientation, mma->bafro);
+	mutex_unlock(&mma->mutex);
+
+	return count;
+}
+static DEVICE_ATTR(position, S_IRUGO, mma8653fc_position_show, NULL);
+
+static struct attribute *mma8653fc_attributes[] = {
+	&dev_attr_position.attr,
+	&dev_attr_standby.attr,
+	&dev_attr_currentmode.attr,
+	NULL,
+};
+
+static const struct attribute_group mma8653fc_attr_group = {
+	.attrs = mma8653fc_attributes,
+};
+
+static u8 mma8653fc_read(struct mma8653fc *mma, unsigned char reg)
+{
+	u8 val;
+
+	val = i2c_smbus_read_byte_data(mma->client, reg);
+	if (val < 0) {
+		dev_err(&mma->client->dev,
+			"failed to read %x register\n", reg);
+	}
+	return val;
+}
+
+static void mma8653fc_write(struct mma8653fc *mma, unsigned char reg,
+			   unsigned char val)
+{
+	int ret;
+
+	ret = i2c_smbus_write_byte_data(mma->client, reg, val);
+	if (ret) {
+		dev_err(&mma->client->dev,
+			"failed to write %x register\n", reg);
+	}
+}
+
+static const struct of_device_id mma8653fc_dt_ids[] = {
+	{ .compatible = "fsl,mma8653fc", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, mma8653fc_dt_ids);
+
+static const struct mma8653fc_pdata *mma8653fc_probe_dt(struct device *dev)
+{
+	struct mma8653fc_pdata *pdata;
+	struct device_node *node = dev->of_node;
+	const struct of_device_id *match;
+	u32 testu32;
+	s32 tests32;
+
+	if (!node) {
+		dev_err(dev, "no associated DT data\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	match = of_match_device(mma8653fc_dt_ids, dev);
+	if (!match) {
+		dev_err(dev, "unknown device model\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata)
+		return ERR_PTR(-ENOMEM);
+
+	*pdata = mma8653fc_default_init;
+
+	/* overwrite from dts */
+	testu32 = pdata->x_axis_offset;
+	tests32 = 0;
+	of_property_read_u32(node, "x-offset", &testu32);
+	tests32 = testu32 - DEFAULT_OFF;
+	if ((tests32) && (tests32 <= DEFAULT_OFF) &&
+	    (tests32 >= -DEFAULT_OFF)) {
+		dev_info(dev, "use %dmg offset on X axis\n", tests32);
+		/* calc register value, resolution: 1.96mg */
+		pdata->x_axis_offset = (s8) (tests32 / 2);
+	}
+	testu32 = pdata->y_axis_offset;
+	tests32 = 0;
+	of_property_read_u32(node, "y-offset", &testu32);
+	tests32 = testu32 - DEFAULT_OFF;
+	if ((tests32) && (tests32 <= DEFAULT_OFF) &&
+	    (tests32 >= -DEFAULT_OFF)) {
+		dev_info(dev, "use %dmg offset on Y axis\n", tests32);
+		pdata->y_axis_offset = (s8) (tests32 / 2);
+	}
+	testu32 = pdata->z_axis_offset;
+	tests32 = 0;
+	of_property_read_u32(node, "z-offset", &testu32);
+	tests32 = testu32 - DEFAULT_OFF;
+	if ((tests32) && (tests32 <= DEFAULT_OFF) &&
+	    (tests32 >= -DEFAULT_OFF)) {
+		dev_info(dev, "use %dmg offset on Z axis\n", tests32);
+		pdata->z_axis_offset = (s8) (tests32 / 2);
+	}
+
+	testu32 = 0;
+	of_property_read_u32(node, "dynamic-range", &testu32);
+	if ((testu32) && (testu32 != 2) && (testu32 != 4) && (testu32 != 8)) {
+		dev_warn(dev, "wrong value for full scale range in dtb\n");
+	} else {
+		if (testu32)
+			pdata->range = testu32;
+	}
+
+	if (of_property_read_bool(node, "auto-wake-sleep"))
+		pdata->auto_wake_sleep = true;
+
+	if (of_property_read_bool(node, "int1"))
+		pdata->int1 = true;
+
+	if (of_property_read_bool(node, "motion-mode"))
+		pdata->motion_mode = true;
+
+	if (of_property_read_bool(node, "ir-data-ready"))
+		pdata->int_src_data_ready = true;
+
+	if (of_property_read_bool(node, "ir-freefall-motion-x"))
+		pdata->int_src_ff_mt_x = true;
+
+	if (of_property_read_bool(node, "ir-freefall-motion-y"))
+		pdata->int_src_ff_mt_y = true;
+
+	if (of_property_read_bool(node, "ir-freefall-motion-z"))
+		pdata->int_src_ff_mt_z = true;
+
+	if (of_property_read_bool(node, "ir-auto-wake"))
+		pdata->int_src_aslp = true;
+
+	if (of_property_read_bool(node, "ir-landscape-portrait"))
+		pdata->int_src_lndprt = true;
+
+	testu32 = 0;
+	of_property_read_u32(node, "irq-threshold", &testu32);
+	/* always uses maximum range +/- 8000g, resolution 63mg */
+	if ((testu32 <= 8000) && (testu32 > 0)) {
+		dev_dbg(dev, "use freefall / motion threshold %dmg\n",
+			 testu32);
+		/* calculate register value from mg */
+		pdata->freefall_motion_thr = (testu32 / 63) + 1;
+	}
+
+	return pdata;
+}
+static int mma8653fc_i2c_probe(struct i2c_client *client,
+				       const struct i2c_device_id *id)
+{
+	struct mma8653fc *mma;
+	const struct mma8653fc_pdata *pdata;
+	int err;
+	u8 byte;
+
+	err = i2c_check_functionality(client->adapter,
+			I2C_FUNC_SMBUS_BYTE_DATA);
+	if (!err) {
+		dev_err(&client->dev, "SMBUS Byte Data not Supported\n");
+		return -EIO;
+	}
+
+	mma = devm_kzalloc(&client->dev, sizeof(*mma), GFP_KERNEL);
+	if (!mma)
+		err = -ENOMEM;
+
+	pdata = dev_get_platdata(&client->dev);
+	if (!pdata) {
+		pdata = mma8653fc_probe_dt(&client->dev);
+		if (IS_ERR(pdata)) {
+			err = PTR_ERR(pdata);
+			dev_err(&client->dev, "pdata from DT failed\n");
+			return err;
+		}
+	}
+	mma->pdata = *pdata;
+	pdata = &mma->pdata;
+	mma->client = client;
+	mma->read = &mma8653fc_read;
+	mma->write = &mma8653fc_write;
+
+	mutex_init(&mma->mutex);
+
+	i2c_set_clientdata(client, mma);
+
+	err = sysfs_create_group(&client->dev.kobj, &mma8653fc_attr_group);
+	if (err)
+		return err;
+
+	byte = mma->read(mma, MMA8653FC_WHO_AM_I);
+	if (byte != MMA8653FC_DEVICE_ID) {
+		dev_err(&client->dev, "wrong device for driver\n");
+		return -ENODEV;
+	}
+	dev_info(&client->dev, "loading driver for device id %x\n", byte);
+
+	mma->irq = irq_of_parse_and_map(client->dev.of_node, 0);
+	if (!mma->irq) {
+		dev_err(&client->dev, "Unable to parse or map IRQ\n");
+		goto no_irq;
+	}
+
+	err = irq_set_irq_type(mma->irq, IRQ_TYPE_EDGE_FALLING);
+	if (err) {
+		dev_err(&client->dev, "set_irq_type failed\n");
+		return err;
+	}
+
+	err = devm_request_threaded_irq(&client->dev, mma->irq, NULL,
+					mma8653fc_irq, IRQF_ONESHOT,
+					dev_name(&mma->client->dev), mma);
+	if (err) {
+		dev_err(&client->dev, "irq %d busy?\n", mma->irq);
+		return err;
+	}
+
+	mma->write(mma, MMA8653FC_CTRL_REG2, SOFT_RESET);
+
+	__mma8653fc_disable(mma);
+	mma->standby = true;
+
+	/* enable desired interrupts */
+	mma->orientation = '\0';
+	mma->bafro = '\0';
+	byte = 0;
+	if (pdata->int_src_data_ready) {
+		byte |= INT_EN_DRDY;
+		dev_dbg(&client->dev, "DATA READY interrupt source enabled\n");
+	}
+	if (pdata->int_src_ff_mt_x || pdata->int_src_ff_mt_y ||
+	    pdata->int_src_ff_mt_z) {
+		byte |= INT_EN_FF_MT;
+		dev_dbg(&client->dev, "FF MT interrupt source enabled\n");
+	}
+	if (pdata->int_src_lndprt) {
+		mma->write(mma, MMA8653FC_PL_CFG, PL_EN);
+		byte |= INT_EN_LNDPRT;
+		dev_dbg(&client->dev, "LNDPRT interrupt source enabled\n");
+	}
+	if (pdata->int_src_aslp) {
+		byte |= INT_EN_ASLP;
+		dev_dbg(&client->dev, "ASLP interrupt source enabled\n");
+	}
+	mma->write(mma, MMA8653FC_CTRL_REG4, byte);
+
+	/* force everything to line 1 */
+	if (pdata->int1) {
+		mma->write(mma, MMA8653FC_CTRL_REG5,
+			   (INT_CFG_ASLP | INT_CFG_LNDPRT |
+			   INT_CFG_FF_MT | INT_CFG_DRDY));
+		dev_dbg(&client->dev, "using interrupt line 1\n");
+	}
+no_irq:
+	/* range mode */
+	byte = mma->read(mma, MMA8653FC_XYZ_DATA_CFG);
+	byte &= ~RANGE_MASK;
+	switch (pdata->range) {
+	case DYN_RANGE_2G:
+		byte |= RANGE2G;
+		dev_dbg(&client->dev, "use 2g range\n");
+		break;
+	case DYN_RANGE_4G:
+		byte |= RANGE4G;
+		dev_dbg(&client->dev, "use 4g range\n");
+		break;
+	case DYN_RANGE_8G:
+		byte |= RANGE8G;
+		dev_dbg(&client->dev, "use 8g range\n");
+		break;
+	default:
+		dev_err(&client->dev, "wrong range mode value\n");
+		return -EINVAL;
+	}
+	mma->write(mma, MMA8653FC_XYZ_DATA_CFG, byte);
+
+	/* data calibration offsets */
+	if (pdata->x_axis_offset)
+		mma->write(mma, MMA8653FC_OFF_X, pdata->x_axis_offset);
+	if (pdata->y_axis_offset)
+		mma->write(mma, MMA8653FC_OFF_Y, pdata->y_axis_offset);
+	if (pdata->z_axis_offset)
+		mma->write(mma, MMA8653FC_OFF_Z, pdata->z_axis_offset);
+
+	/* if autosleep, wake on both landscape and motion changes */
+	if (pdata->auto_wake_sleep) {
+		byte = 0;
+		byte |= WAKE_LNDPRT;
+		byte |= WAKE_FF_MT;
+		mma->write(mma, MMA8653FC_CTRL_REG3, byte);
+		mma->write(mma, MMA8653FC_CTRL_REG2, SLPE);
+		dev_dbg(&client->dev, "auto sleep enabled\n");
+	}
+
+	/* data rates */
+	byte = 0;
+	byte = mma->read(mma, MMA8653FC_CTRL_REG1);
+	byte &= ~ODR_MASK;
+	byte |= ODR_DEFAULT;
+	byte &= ~ASLP_RATE_MASK;
+	byte |= ASLP_RATE_DEFAULT;
+	mma->write(mma, MMA8653FC_CTRL_REG1, byte);
+
+	/* freefall / motion config */
+	byte = 0;
+	if (pdata->motion_mode) {
+		byte |= FF_MT_CFG_OAE;
+		dev_dbg(&client->dev, "detect motion instead of freefall\n");
+	}
+	byte |= FF_MT_CFG_ELE;
+	if (pdata->int_src_ff_mt_x)
+		byte |= FF_MT_CFG_XEFE;
+	if (pdata->int_src_ff_mt_y)
+		byte |= FF_MT_CFG_YEFE;
+	if (pdata->int_src_ff_mt_z)
+		byte |= FF_MT_CFG_ZEFE;
+	mma->write(mma, MMA8653FC_FF_MT_CFG, byte);
+
+	if (pdata->freefall_motion_thr) {
+		mma->write(mma, MMA8653FC_FF_MT_THS,
+			   pdata->freefall_motion_thr);
+		/* calculate back to mg */
+		dev_dbg(&client->dev, "threshold set to %dmg\n",
+			 (63 * pdata->freefall_motion_thr) - 1);
+	}
+
+	return 0;
+}
+
+static int mma8653fc_remove(struct i2c_client *client)
+{
+	dev_dbg(&client->dev, "unregistered accelerometer\n");
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int mma8653fc_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct mma8653fc *mma = i2c_get_clientdata(client);
+
+	__mma8653fc_disable(mma);
+
+	return 0;
+}
+
+static int mma8653fc_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct mma8653fc *mma = i2c_get_clientdata(client);
+
+	__mma8653fc_enable(mma);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(mma8653fc_pm_ops, mma8653fc_suspend, mma8653fc_resume);
+#define MMA8653FC_PM_OPS (&mma8653fc_pm_ops)
+#else
+#define MMA8653FC_PM_OPS NULL
+#endif
+
+static const struct i2c_device_id mma8653fc_id[] = {
+	{ DRV_NAME, 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, mma8653fc_id);
+
+static struct i2c_driver mma8653fc_driver = {
+	.driver = {
+		.name = DRV_NAME,
+		.owner = THIS_MODULE,
+		.of_match_table = mma8653fc_dt_ids,
+		.pm = MMA8653FC_PM_OPS,
+	},
+	.probe    = mma8653fc_i2c_probe,
+	.remove   = mma8653fc_remove,
+	.id_table = mma8653fc_id,
+};
+
+module_i2c_driver(mma8653fc_driver);
+
+MODULE_AUTHOR("Martin Kepplinger <martin.kepplinger@theobroma-systems.com");
+MODULE_DESCRIPTION("Freescale's MMA8653FC Three-Axis Accelerometer I2C Driver");
+MODULE_LICENSE("GPL");