linux-imx

// SPDX-License-Identifier: GPL-2.0

/*

 * PNI RM3100 3-axis geomagnetic sensor driver core.

 *

 * Copyright (C) 2018 Song Qiang <songqiang1304521@gmail.com>

 *

 * User Manual available at

 * <https://www.pnicorp.com/download/rm3100-user-manual/>

 *

 * TODO: event generation, pm.

 */

​

#include <linux/delay.h>

#include <linux/interrupt.h>

#include <linux/module.h>

#include <linux/slab.h>

​

#include <linux/iio/buffer.h>

#include <linux/iio/iio.h>

#include <linux/iio/sysfs.h>

#include <linux/iio/trigger.h>

#include <linux/iio/triggered_buffer.h>

#include <linux/iio/trigger_consumer.h>

​

#include "rm3100.h"

​

/* Cycle Count Registers. */

#define RM3100_REG_CC_X         0x05

#define RM3100_REG_CC_Y         0x07

#define RM3100_REG_CC_Z         0x09

​

/* Poll Measurement Mode register. */

#define RM3100_REG_POLL         0x00

#define     RM3100_POLL_X       BIT(4)

#define     RM3100_POLL_Y       BIT(5)

#define     RM3100_POLL_Z       BIT(6)

​

/* Continuous Measurement Mode register. */

#define RM3100_REG_CMM          0x01

#define     RM3100_CMM_START    BIT(0)

#define     RM3100_CMM_X        BIT(4)

#define     RM3100_CMM_Y        BIT(5)

#define     RM3100_CMM_Z        BIT(6)

​

/* TiMe Rate Configuration register. */

#define RM3100_REG_TMRC         0x0B

#define RM3100_TMRC_OFFSET      0x92

​

/* Result Status register. */

#define RM3100_REG_STATUS       0x34

#define     RM3100_STATUS_DRDY  BIT(7)

​

/* Measurement result registers. */

#define RM3100_REG_MX2          0x24

#define RM3100_REG_MY2          0x27

#define RM3100_REG_MZ2          0x2a

​

#define RM3100_W_REG_START      RM3100_REG_POLL

#define RM3100_W_REG_END        RM3100_REG_TMRC

#define RM3100_R_REG_START      RM3100_REG_POLL

#define RM3100_R_REG_END        RM3100_REG_STATUS

#define RM3100_V_REG_START      RM3100_REG_POLL

#define RM3100_V_REG_END        RM3100_REG_STATUS

​

/*

 * This is computed by hand, is the sum of channel storage bits and padding

 * bits, which is 4+4+4+12=24 in here.

 */

#define RM3100_SCAN_BYTES       24

​

#define RM3100_CMM_AXIS_SHIFT       4

​

struct rm3100_data {

    struct regmap *regmap;

    struct completion measuring_done;

    bool use_interrupt;

    int conversion_time;

    int scale;

    u8 buffer[RM3100_SCAN_BYTES];

    struct iio_trigger *drdy_trig;

​

    /*

     * This lock is for protecting the consistency of series of i2c

     * operations, that is, to make sure a measurement process will

     * not be interrupted by a set frequency operation, which should

     * be taken where a series of i2c operation starts, released where

     * the operation ends.

     */

    struct mutex lock;

};

​

static const struct regmap_range rm3100_readable_ranges[] = {