adxl34x.h

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/*
 * 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 during the
     * tap_latency period, i.e. after the first tap but before the
     * opening of the second tap window.
     */

#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 ADXL34x datasheet's 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 the
     * Sleep Bit section of the ADXL34x datasheet for more information.
     */

#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;

    /*
     * When acceleration measurements are received from the ADXL34x
     * events are sent to the event subsystem. The following settings
     * select the event type and event code for new x, y and z axis data
     * respectively.
     */
    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 */

    /*
     * Use ADXL34x INT2 pin instead of INT1 pin for interrupt output
     */
    u8 use_int2;

    /*
     * ADXL346 only ORIENTATION SENSING feature
     * The orientation function of the ADXL346 reports both 2-D and
     * 3-D orientation concurrently.
     */

#define ADXL_EN_ORIENTATION_2D      1
#define ADXL_EN_ORIENTATION_3D      2
#define ADXL_EN_ORIENTATION_2D_3D   3

    u8 orientation_enable;

    /*
     * The width of the deadzone region between two or more
     * orientation positions is determined by setting the Deadzone
     * value. The deadzone region size can be specified with a
     * resolution of 3.6deg. The deadzone angle represents the total
     * angle where the orientation is considered invalid.
     */

#define ADXL_DEADZONE_ANGLE_0p0     0   /* !!!0.0 [deg] */
#define ADXL_DEADZONE_ANGLE_3p6     1   /* 3.6 [deg] */
#define ADXL_DEADZONE_ANGLE_7p2     2   /* 7.2 [deg] */
#define ADXL_DEADZONE_ANGLE_10p8    3   /* 10.8 [deg] */
#define ADXL_DEADZONE_ANGLE_14p4    4   /* 14.4 [deg] */
#define ADXL_DEADZONE_ANGLE_18p0    5   /* 18.0 [deg] */
#define ADXL_DEADZONE_ANGLE_21p6    6   /* 21.6 [deg] */
#define ADXL_DEADZONE_ANGLE_25p2    7   /* 25.2 [deg] */

    u8 deadzone_angle;

    /*
     * To eliminate most human motion such as walking or shaking,
     * a Divisor value should be selected to effectively limit the
     * orientation bandwidth. Set the depth of the filter used to
     * low-pass filter the measured acceleration for stable
     * orientation sensing
     */

#define ADXL_LP_FILTER_DIVISOR_2    0
#define ADXL_LP_FILTER_DIVISOR_4    1
#define ADXL_LP_FILTER_DIVISOR_8    2
#define ADXL_LP_FILTER_DIVISOR_16   3
#define ADXL_LP_FILTER_DIVISOR_32   4
#define ADXL_LP_FILTER_DIVISOR_64   5
#define ADXL_LP_FILTER_DIVISOR_128  6
#define ADXL_LP_FILTER_DIVISOR_256  7

    u8 divisor_length;

    u32 ev_codes_orient_2d[4];  /* EV_KEY {+X, -X, +Y, -Y} */
    u32 ev_codes_orient_3d[6];  /* EV_KEY {+Z, +Y, +X, -X, -Y, -Z} */
};
#endif