ad525x_dpot-spi.c

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/*
 * Driver for the Analog Devices digital potentiometers (SPI bus)
 *
 * Copyright (C) 2010-2011 Michael Hennerich, Analog Devices Inc.
 *
 * Licensed under the GPL-2 or later.
 */

#include <linux/spi/spi.h>
#include <linux/module.h>

#include "ad525x_dpot.h"

/* SPI bus functions */
static int write8(void *client, u8 val)
{
    u8 data = val;
    return spi_write(client, &data, 1);
}

static int write16(void *client, u8 reg, u8 val)
{
    u8 data[2] = {reg, val};
    return spi_write(client, data, 2);
}

static int write24(void *client, u8 reg, u16 val)
{
    u8 data[3] = {reg, val >> 8, val};
    return spi_write(client, data, 3);
}

static int read8(void *client)
{
    int ret;
    u8 data;
    ret = spi_read(client, &data, 1);
    if (ret < 0)
        return ret;

    return data;
}

static int read16(void *client, u8 reg)
{
    int ret;
    u8 buf_rx[2];

    write16(client, reg, 0);
    ret = spi_read(client, buf_rx, 2);
    if (ret < 0)
        return ret;

    return (buf_rx[0] << 8) |  buf_rx[1];
}

static int read24(void *client, u8 reg)
{
    int ret;
    u8 buf_rx[3];

    write24(client, reg, 0);
    ret = spi_read(client, buf_rx, 3);
    if (ret < 0)
        return ret;

    return (buf_rx[1] << 8) |  buf_rx[2];
}

static const struct ad_dpot_bus_ops bops = {
    .read_d8    = read8,
    .read_r8d8  = read16,
    .read_r8d16 = read24,
    .write_d8   = write8,
    .write_r8d8 = write16,
    .write_r8d16    = write24,
};
static int __devinit ad_dpot_spi_probe(struct spi_device *spi)
{
    struct ad_dpot_bus_data bdata = {
        .client = spi,
        .bops = &bops,
    };

    return ad_dpot_probe(&spi->dev, &bdata,
                 spi_get_device_id(spi)->driver_data,
                 spi_get_device_id(spi)->name);
}

static int __devexit ad_dpot_spi_remove(struct spi_device *spi)
{
    return ad_dpot_remove(&spi->dev);
}

static const struct spi_device_id ad_dpot_spi_id[] = {
    {"ad5160", AD5160_ID},
    {"ad5161", AD5161_ID},
    {"ad5162", AD5162_ID},
    {"ad5165", AD5165_ID},
    {"ad5200", AD5200_ID},
    {"ad5201", AD5201_ID},
    {"ad5203", AD5203_ID},
    {"ad5204", AD5204_ID},
    {"ad5206", AD5206_ID},
    {"ad5207", AD5207_ID},
    {"ad5231", AD5231_ID},
    {"ad5232", AD5232_ID},
    {"ad5233", AD5233_ID},
    {"ad5235", AD5235_ID},
    {"ad5260", AD5260_ID},
    {"ad5262", AD5262_ID},
    {"ad5263", AD5263_ID},
    {"ad5290", AD5290_ID},
    {"ad5291", AD5291_ID},
    {"ad5292", AD5292_ID},
    {"ad5293", AD5293_ID},
    {"ad7376", AD7376_ID},
    {"ad8400", AD8400_ID},
    {"ad8402", AD8402_ID},
    {"ad8403", AD8403_ID},
    {"adn2850", ADN2850_ID},
    {"ad5270", AD5270_ID},
    {"ad5271", AD5271_ID},
    {}
};
MODULE_DEVICE_TABLE(spi, ad_dpot_spi_id);

static struct spi_driver ad_dpot_spi_driver = {
    .driver = {
        .name   = "ad_dpot",
        .owner  = THIS_MODULE,
    },
    .probe      = ad_dpot_spi_probe,
    .remove     = __devexit_p(ad_dpot_spi_remove),
    .id_table   = ad_dpot_spi_id,
};

module_spi_driver(ad_dpot_spi_driver);

MODULE_AUTHOR("Michael Hennerich <[email protected]>");
MODULE_DESCRIPTION("digital potentiometer SPI bus driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("spi:ad_dpot");