root/drivers/iio/pressure/mprls0025pa.h
/* SPDX-License-Identifier: GPL-2.0 */
/*
 * MPRLS0025PA - Honeywell MicroPressure pressure sensor series driver
 *
 * Copyright (c) Andreas Klinger <ak@it-klinger.de>
 *
 * Data sheet:
 *  https://prod-edam.honeywell.com/content/dam/honeywell-edam/sps/siot/en-us/products/sensors/pressure-sensors/board-mount-pressure-sensors/micropressure-mpr-series/documents/sps-siot-mpr-series-datasheet-32332628-ciid-172626.pdf
 */

#ifndef _MPRLS0025PA_H
#define _MPRLS0025PA_H

#include <linux/completion.h>
#include <linux/mutex.h>
#include <linux/types.h>

#include <linux/iio/iio.h>

#define MPR_MEASUREMENT_RD_SIZE 4
#define MPR_CMD_NOP      0xf0
#define MPR_CMD_SYNC     0xaa
#define MPR_PKT_NOP_LEN  MPR_MEASUREMENT_RD_SIZE
#define MPR_PKT_SYNC_LEN 3

struct device;

struct mpr_data;
struct mpr_ops;

enum mpr_func_id {
        MPR_FUNCTION_A,
        MPR_FUNCTION_B,
        MPR_FUNCTION_C,
};

/**
 * struct mpr_data
 * @dev: current device structure
 * @ops: functions that implement the sensor reads/writes, bus init
 * @lock: access to device during read
 * @pmin: minimal pressure in pascal
 * @pmax: maximal pressure in pascal
 * @function: transfer function
 * @outmin: minimum raw pressure in counts (based on transfer function)
 * @outmax: maximum raw pressure in counts (based on transfer function)
 * @scale: pressure scale
 * @scale2: pressure scale, decimal number
 * @offset: pressure offset
 * @gpiod_reset: reset
 * @irq: end of conversion irq. used to distinguish between irq mode and
 *       reading in a loop until data is ready
 * @completion: handshake from irq to read
 * @chan: channel values for buffered mode
 * @chan.pres: pressure value
 * @chan.ts: timestamp
 * @rx_buf: raw conversion data
 * @tx_buf: output buffer
 */
struct mpr_data {
        struct device           *dev;
        const struct mpr_ops    *ops;
        struct mutex            lock;
        u32                     pmin;
        u32                     pmax;
        enum mpr_func_id        function;
        u32                     outmin;
        u32                     outmax;
        int                     scale;
        int                     scale2;
        int                     offset;
        struct gpio_desc        *gpiod_reset;
        int                     irq;
        struct completion       completion;
        struct {
                s32 pres;
                aligned_s64 ts;
        } chan;
        u8 rx_buf[MPR_MEASUREMENT_RD_SIZE] __aligned(IIO_DMA_MINALIGN);
        u8 tx_buf[MPR_MEASUREMENT_RD_SIZE];
};

struct mpr_ops {
        int (*read)(struct mpr_data *data, const u8 cmd, const u8 cnt);
        int (*write)(struct mpr_data *data, const u8 cmd, const u8 cnt);
};

int mpr_common_probe(struct device *dev, const struct mpr_ops *ops, int irq);

#endif