Input: add driver for ADXL345/346 Digital Accelerometers

This is a driver for the ADXL345/346 Three-Axis Digital Accelerometers.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Chris Verges <chrisv@cyberswitching.com>
Signed-off-by: Luotao Fu <l.fu@pengutronix.de>
Signed-off-by: Barry Song <barry.song@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

1 files changed, 293 insertions, 0 deletions

diff --git a/include/linux/input/adxl34x.h b/include/linux/input/adxl34x.h
new file mode 100644
index 00000000000..71211823803
--- /dev/null
+++ b/include/linux/input/adxl34x.h
@@ -0,0 +1,293 @@
+/*
+ * include/linux/input/adxl34x.h
+ *
+ * Digital Accelerometer characteristics are highly application specific
+ * and may vary between boards and models. The platform_data for the
+ * device's "struct device" holds this information.
+ *
+ * Copyright 2009 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#ifndef __LINUX_INPUT_ADXL34X_H__
+#define __LINUX_INPUT_ADXL34X_H__
+
+struct adxl34x_platform_data {
+
+	/*
+	 * X,Y,Z Axis Offset:
+	 * offer user offset adjustments in twoscompliment
+	 * form with a scale factor of 15.6 mg/LSB (i.e. 0x7F = +2 g)
+	 */
+
+	s8 x_axis_offset;
+	s8 y_axis_offset;
+	s8 z_axis_offset;
+
+	/*
+	 * TAP_X/Y/Z Enable: Setting TAP_X, Y, or Z Enable enables X,
+	 * Y, or Z participation in Tap detection. A '0' excludes the
+	 * selected axis from participation in Tap detection.
+	 * Setting the SUPPRESS bit suppresses Double Tap detection if
+	 * acceleration greater than tap_threshold is present between
+	 * taps.
+	 */
+
+#define ADXL_SUPPRESS	(1 << 3)
+#define ADXL_TAP_X_EN	(1 << 2)
+#define ADXL_TAP_Y_EN	(1 << 1)
+#define ADXL_TAP_Z_EN	(1 << 0)
+
+	u8 tap_axis_control;
+
+	/*
+	 * tap_threshold:
+	 * holds the threshold value for tap detection/interrupts.
+	 * The data format is unsigned. The scale factor is 62.5 mg/LSB
+	 * (i.e. 0xFF = +16 g). A zero value may result in undesirable
+	 * behavior if Tap/Double Tap is enabled.
+	 */
+
+	u8 tap_threshold;
+
+	/*
+	 * tap_duration:
+	 * is an unsigned time value representing the maximum
+	 * time that an event must be above the tap_threshold threshold
+	 * to qualify as a tap event. The scale factor is 625 us/LSB. A zero
+	 * value will prevent Tap/Double Tap functions from working.
+	 */
+
+	u8 tap_duration;
+
+	/*
+	 * tap_latency:
+	 * is an unsigned time value representing the wait time
+	 * from the detection of a tap event to the opening of the time
+	 * window tap_window for a possible second tap event. The scale
+	 * factor is 1.25 ms/LSB. A zero value will disable the Double Tap
+	 * function.
+	 */
+
+	u8 tap_latency;
+
+	/*
+	 * tap_window:
+	 * is an unsigned time value representing the amount
+	 * of time after the expiration of tap_latency during which a second
+	 * tap can begin. The scale factor is 1.25 ms/LSB. A zero value will
+	 * disable the Double Tap function.
+	 */
+
+	u8 tap_window;
+
+	/*
+	 * act_axis_control:
+	 * X/Y/Z Enable: A '1' enables X, Y, or Z participation in activity
+	 * or inactivity detection. A '0' excludes the selected axis from
+	 * participation. If all of the axes are excluded, the function is
+	 * disabled.
+	 * AC/DC: A '0' = DC coupled operation and a '1' = AC coupled
+	 * operation. In DC coupled operation, the current acceleration is
+	 * compared with activity_threshold and inactivity_threshold directly
+	 * to determine whether activity or inactivity is detected. In AC
+	 * coupled operation for activity detection, the acceleration value
+	 * at the start of activity detection is taken as a reference value.
+	 * New samples of acceleration are then compared to this
+	 * reference value and if the magnitude of the difference exceeds
+	 * activity_threshold the device will trigger an activity interrupt. In
+	 * AC coupled operation for inactivity detection, a reference value
+	 * is used again for comparison and is updated whenever the
+	 * device exceeds the inactivity threshold. Once the reference
+	 * value is selected, the device compares the magnitude of the
+	 * difference between the reference value and the current
+	 * acceleration with inactivity_threshold. If the difference is below
+	 * inactivity_threshold for a total of inactivity_time, the device is
+	 * considered inactive and the inactivity interrupt is triggered.
+	 */
+
+#define ADXL_ACT_ACDC		(1 << 7)
+#define ADXL_ACT_X_EN		(1 << 6)
+#define ADXL_ACT_Y_EN		(1 << 5)
+#define ADXL_ACT_Z_EN		(1 << 4)
+#define ADXL_INACT_ACDC		(1 << 3)
+#define ADXL_INACT_X_EN		(1 << 2)
+#define ADXL_INACT_Y_EN		(1 << 1)
+#define ADXL_INACT_Z_EN		(1 << 0)
+
+	u8 act_axis_control;
+
+	/*
+	 * activity_threshold:
+	 * holds the threshold value for activity detection.
+	 * The data format is unsigned. The scale factor is
+	 * 62.5 mg/LSB. A zero value may result in undesirable behavior if
+	 * Activity interrupt is enabled.
+	 */
+
+	u8 activity_threshold;
+
+	/*
+	 * inactivity_threshold:
+	 * holds the threshold value for inactivity
+	 * detection. The data format is unsigned. The scale
+	 * factor is 62.5 mg/LSB. A zero value may result in undesirable
+	 * behavior if Inactivity interrupt is enabled.
+	 */
+
+	u8 inactivity_threshold;
+
+	/*
+	 * inactivity_time:
+	 * is an unsigned time value representing the
+	 * amount of time that acceleration must be below the value in
+	 * inactivity_threshold for inactivity to be declared. The scale factor
+	 * is 1 second/LSB. Unlike the other interrupt functions, which
+	 * operate on unfiltered data, the inactivity function operates on the
+	 * filtered output data. At least one output sample must be
+	 * generated for the inactivity interrupt to be triggered. This will
+	 * result in the function appearing un-responsive if the
+	 * inactivity_time register is set with a value less than the time
+	 * constant of the Output Data Rate. A zero value will result in an
+	 * interrupt when the output data is below inactivity_threshold.
+	 */
+
+	u8 inactivity_time;
+
+	/*
+	 * free_fall_threshold:
+	 * holds the threshold value for Free-Fall detection.
+	 * The data format is unsigned. The root-sum-square(RSS) value
+	 * of all axes is calculated and compared to the value in
+	 * free_fall_threshold to determine if a free fall event may be
+	 * occurring.  The scale factor is 62.5 mg/LSB. A zero value may
+	 * result in undesirable behavior if Free-Fall interrupt is
+	 * enabled. Values between 300 and 600 mg (0x05 to 0x09) are
+	 * recommended.
+	 */
+
+	u8 free_fall_threshold;
+
+	/*
+	 * free_fall_time:
+	 * is an unsigned time value representing the minimum
+	 * time that the RSS value of all axes must be less than
+	 * free_fall_threshold to generate a Free-Fall interrupt. The
+	 * scale factor is 5 ms/LSB. A zero value may result in
+	 * undesirable behavior if Free-Fall interrupt is enabled.
+	 * Values between 100 to 350 ms (0x14 to 0x46) are recommended.
+	 */
+
+	u8 free_fall_time;
+
+	/*
+	 * data_rate:
+	 * Selects device bandwidth and output data rate.
+	 * RATE = 3200 Hz / (2^(15 - x)). Default value is 0x0A, or 100 Hz
+	 * Output Data Rate. An Output Data Rate should be selected that
+	 * is appropriate for the communication protocol and frequency
+	 * selected. Selecting too high of an Output Data Rate with a low
+	 * communication speed will result in samples being discarded.
+	 */
+
+	u8 data_rate;
+
+	/*
+	 * data_range:
+	 * FULL_RES: When this bit is set with the device is
+	 * in Full-Resolution Mode, where the output resolution increases
+	 * with RANGE to maintain a 4 mg/LSB scale factor. When this
+	 * bit is cleared the device is in 10-bit Mode and RANGE determine the
+	 * maximum g-Range and scale factor.
+	 */
+
+#define ADXL_FULL_RES		(1 << 3)
+#define ADXL_RANGE_PM_2g	0
+#define ADXL_RANGE_PM_4g	1
+#define ADXL_RANGE_PM_8g	2
+#define ADXL_RANGE_PM_16g	3
+
+	u8 data_range;
+
+	/*
+	 * low_power_mode:
+	 * A '0' = Normal operation and a '1' = Reduced
+	 * power operation with somewhat higher noise.
+	 */
+
+	u8 low_power_mode;
+
+	/*
+	 * power_mode:
+	 * LINK: A '1' with both the activity and inactivity functions
+	 * enabled will delay the start of the activity function until
+	 * inactivity is detected. Once activity is detected, inactivity
+	 * detection will begin and prevent the detection of activity. This
+	 * bit serially links the activity and inactivity functions. When '0'
+	 * the inactivity and activity functions are concurrent. Additional
+	 * information can be found in the Application section under Link
+	 * Mode.
+	 * AUTO_SLEEP: A '1' sets the ADXL34x to switch to Sleep Mode
+	 * when inactivity (acceleration has been below inactivity_threshold
+	 * for at least inactivity_time) is detected and the LINK bit is set.
+	 * A '0' disables automatic switching to Sleep Mode. See SLEEP
+	 * for further description.
+	 */
+
+#define ADXL_LINK	(1 << 5)
+#define ADXL_AUTO_SLEEP	(1 << 4)
+
+	u8 power_mode;
+
+	/*
+	 * fifo_mode:
+	 * BYPASS The FIFO is bypassed
+	 * FIFO   FIFO collects up to 32 values then stops collecting data
+	 * STREAM FIFO holds the last 32 data values. Once full, the FIFO's
+	 *        oldest data is lost as it is replaced with newer data
+	 *
+	 * DEFAULT should be ADXL_FIFO_STREAM
+	 */
+
+#define ADXL_FIFO_BYPASS	0
+#define ADXL_FIFO_FIFO		1
+#define ADXL_FIFO_STREAM	2
+
+	u8 fifo_mode;
+
+	/*
+	 * watermark:
+	 * The Watermark feature can be used to reduce the interrupt load
+	 * of the system. The FIFO fills up to the value stored in watermark
+	 * [1..32] and then generates an interrupt.
+	 * A '0' disables the watermark feature.
+	 */
+
+	u8 watermark;
+
+	u32 ev_type;	/* EV_ABS or EV_REL */
+
+	u32 ev_code_x;	/* ABS_X,Y,Z or REL_X,Y,Z */
+	u32 ev_code_y;	/* ABS_X,Y,Z or REL_X,Y,Z */
+	u32 ev_code_z;	/* ABS_X,Y,Z or REL_X,Y,Z */
+
+	/*
+	 * A valid BTN or KEY Code; use tap_axis_control to disable
+	 * event reporting
+	 */
+
+	u32 ev_code_tap[3];	/* EV_KEY {X-Axis, Y-Axis, Z-Axis} */
+
+	/*
+	 * A valid BTN or KEY Code for Free-Fall or Activity enables
+	 * input event reporting. A '0' disables the Free-Fall or
+	 * Activity reporting.
+	 */
+
+	u32 ev_code_ff;	/* EV_KEY */
+	u32 ev_code_act_inactivity;	/* EV_KEY */
+
+	u8 use_int2;
+};
+#endif