C180_oyster_driver/gsensor.h

/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Memsic MXC400xXC Gsensor driver for screen orientation
 * 
 */

#ifndef __GSENSOR_H
#define __GSENSOR_H

#include <linux/types.h>
#include <linux/iio/iio.h>
#include <linux/i2c.h>
#include <linux/iio/trigger.h>
#include <linux/iio/triggered_buffer.h>

/* Gsensor orientation values (hex per API spec) */
enum gsensor_orientation_hex
{
    GSENSOR_ORIENT_UNKNOWN_HEX        = 0x00,
    GSENSOR_ORIENT_PORTRAIT_HEX       = 0x14,
    GSENSOR_ORIENT_LANDSCAPE_HEX      = 0x15,
    GSENSOR_ORIENT_PORTRAIT_FLIP_HEX  = 0x16,
    GSENSOR_ORIENT_LANDSCAPE_FLIP_HEX = 0x17,
};

/* Gsensor orientation strings */
#define GSENSOR_ORIENT_PORTRAIT_STR       "portrait"
#define GSENSOR_ORIENT_LANDSCAPE_STR      "landscape"
#define GSENSOR_ORIENT_PORTRAIT_FLIP_STR  "portrait_flip"
#define GSENSOR_ORIENT_LANDSCAPE_FLIP_STR "landscape_flip"

/* Gsensor mode bits (per API spec) */
#define GSENSOR_MODE_SOFT_RESET           BIT(2) /* EC17: soft reset */
#define GSENSOR_MODE_INITIALIZED          BIT(1) /* EC16: 0=not init, 1=init */
#define GSENSOR_MODE_INTERRUPT            BIT(0) /* 0=poll, 1=interrupt */

/* Memsic MXC400xXC Register Definitions */
#define MXC400X_REG_WHO_AM_I              0x00
#define MXC400X_WHO_AM_I_VALUE            0x20

#define MXC400X_REG_XOUT_U                0x04
#define MXC400X_REG_XOUT_L                0x05
#define MXC400X_REG_YOUT_U                0x06
#define MXC400X_REG_YOUT_L                0x07
#define MXC400X_REG_ZOUT_U                0x08
#define MXC400X_REG_ZOUT_L                0x09

#define MXC400X_REG_CONTROL               0x0A
#define MXC400X_CONTROL_MODE_MASK         0x03
#define MXC400X_CONTROL_MODE_STANDBY      0x00
#define MXC400X_CONTROL_MODE_ACTIVE       0x01
#define MXC400X_CONTROL_MODE_RESET        0x02

#define MXC400X_REG_INT_ENABLE            0x0B
#define MXC400X_INT_ENABLE_DRDY           BIT(0)

#define MXC400X_REG_INT_STATUS            0x0C


/* ST LIS2DH12 / SC7A20 register */
#define ST_ACCEL_WHO_AM_I_ADDR         0x0F
#define ST_ACCEL_WHO_AM_I_VALUE        0x33  /* LIS2DH12 / SC7A20 */
#define ST_ACCEL_CTRL_REG1_ADDR        0x20
#define ST_ACCEL_CTRL_REG4_ADDR        0x23
#define ST_ACCEL_OUT_X_L_ADDR          0x28
#define ST_ACCEL_OUT_X_H_ADDR          0x29
#define ST_ACCEL_OUT_Y_L_ADDR          0x2A
#define ST_ACCEL_OUT_Y_H_ADDR          0x2B
#define ST_ACCEL_OUT_Z_L_ADDR          0x2C
#define ST_ACCEL_OUT_Z_H_ADDR          0x2D
#define ST_ACCEL_STATUS_REG_ADDR       0x27
#define ST_ACCEL_STATUS_DRDY           0x07

/* Driver Constants */
#define GSENSOR_NUMBER_DATA_CHANNELS      3
#define GSENSOR_DEBOUNCE_MS               100
#define MXC400X_SCALE_FACTOR              1000 /* mg per count at 2g range */

/* Default I2C address */
#define MXC400X_DEFAULT_I2C_ADDR          0x15

/* Sensor Settings Structure */
struct gsensor_fs_avl
{
    unsigned int num;   /* Full scale value in g */
    unsigned int value; /* Register value */
    unsigned int gain;  /* Gain in micro g per LSB */
};

struct gsensor_odr_avl
{
    unsigned int hz;    /* Output data rate in Hz */
    unsigned int value; /* Register value */
};

struct gsensor_settings
{
    u8 wai;                         /* WHO_AM_I expected value */
    u8 wai_addr;                    /* WHO_AM_I register address */
    const char **sensors_supported; /* Supported device names */

    /* Channel configuration */
    const struct iio_chan_spec *ch;
    int num_channels;

    /* ODR configuration */
    struct
    {
        u8 addr;
        u8 mask;
        const struct gsensor_odr_avl *odr_avl;
        int num_odr;
    } odr;

    /* Power mode configuration */
    struct
    {
        u8 addr;
        u8 mask;
        u8 value_on;
        u8 value_off;
    } pw;

    /* Full scale configuration */
    struct
    {
        u8 addr;
        u8 mask;
        const struct gsensor_fs_avl *fs_avl;
        int num_fs;
    } fs;

    /* Block Data Update */
    struct
    {
        u8 addr;
        u8 mask;
    } bdu;

    /* Data ready interrupt */
    struct
    {
        struct
        {
            u8 addr;
            u8 mask;
        } int1;
        u8 addr_ihl;
        u8 mask_ihl;
        struct
        {
            u8 addr;
            u8 mask;
        } stat_drdy;
    } drdy_irq;

    /* SPI/I2C interface mode */
    struct
    {
        u8 addr;
        u8 value;
    } sim;

    bool multi_read_bit;
    unsigned int bootime;
};

/* Driver Data Structure */
struct gsensor_data
{
    struct i2c_client *client;
    struct device *dev;
    struct mutex lock; /* Protects data access */

    /* Sensor settings */
    const struct gsensor_settings *sensor_settings;

    /* Current configuration */
    const struct gsensor_fs_avl *current_fullscale;
    unsigned int odr;

    /* Orientation data */
    enum gsensor_orientation_hex orientation_hex;
    char orientation_str[32];
    struct delayed_work debounce_work;
    enum gsensor_orientation_hex pending_orientation;
    unsigned long last_change_jiffies;

    /* State */
    bool enabled;
    bool initialized;
    bool interrupt_mode;
    bool irq_enabled;

    /* IIO related */
    struct iio_dev *indio_dev;

    /* Verifone sysfs */
    struct kobject *verifone_kobj;

    /* Regulators (optional) */
    struct regulator *vdd;
    struct regulator *vdd_io;
};

/* Core functions */
int gsensor_common_probe(struct iio_dev *indio_dev);
void gsensor_common_remove(struct iio_dev *indio_dev);
const struct gsensor_settings *gsensor_get_settings(const char *name);

/* Buffer functions */
int gsensor_allocate_ring(struct iio_dev *indio_dev);
int gsensor_trig_set_state(struct iio_trigger *trig, bool state);

int gsensor_allocate_trigger(struct iio_dev *indio_dev);
extern const struct iio_trigger_ops gsensor_trigger_ops;

/* Power management */
int gsensor_power_enable(struct iio_dev *indio_dev);
int gsensor_power_disable(struct iio_dev *indio_dev);

/* I2C functions */
int gsensor_i2c_read(struct device *dev, u8 reg, u8 *data, size_t len);
int gsensor_i2c_write(struct device *dev, u8 reg, u8 value);
int gsensor_init_main(void);
void gsensor_exit_main(void);

int gsensor_read_raw_data(struct gsensor_data *gs, int *x, int *y, int *z);
int gsensor_set_enable(struct gsensor_data *gs, bool enable);
int gsensor_set_dataready_irq(struct gsensor_data *gs, bool enable);

/* Helper macros */
#define GSENSOR_DEV_ATTR_SAMP_FREQ_AVAIL()                                     \
    IIO_DEV_ATTR_SAMP_FREQ_AVAIL(gsensor_show_available_odr)

#define GSENSOR_DEV_ATTR_SCALE_AVAIL()                                         \
    IIO_DEVICE_ATTR(in_accel_scale_available, 0444,                            \
                    gsensor_show_available_scale, NULL, 0)

#endif /* __GSENSOR_H */