LXR linux/drivers/misc/ad525x

   1/*
   2 * Driver for the Analog Devices digital potentiometers (SPI bus)
   3 *
   4 * Copyright (C) 2010-2011 Michael Hennerich, Analog Devices Inc.
   5 *
   6 * Licensed under the GPL-2 or later.
   7 */
   8
   9#include <linux/spi/spi.h>
  10#include <linux/module.h>
  11
  12#include "ad525x_dpot.h"
  13
  14/* SPI bus functions */
  15static int write8(void *client, u8 val)
  16{
  17        u8 data = val;
  18
  19        return spi_write(client, &data, 1);
  20}
  21
  22static int write16(void *client, u8 reg, u8 val)
  23{
  24        u8 data[2] = {reg, val};
  25
  26        return spi_write(client, data, 2);
  27}
  28
  29static int write24(void *client, u8 reg, u16 val)
  30{
  31        u8 data[3] = {reg, val >> 8, val};
  32
  33        return spi_write(client, data, 3);
  34}
  35
  36static int read8(void *client)
  37{
  38        int ret;
  39        u8 data;
  40
  41        ret = spi_read(client, &data, 1);
  42        if (ret < 0)
  43                return ret;
  44
  45        return data;
  46}
  47
  48static int read16(void *client, u8 reg)
  49{
  50        int ret;
  51        u8 buf_rx[2];
  52
  53        write16(client, reg, 0);
  54        ret = spi_read(client, buf_rx, 2);
  55        if (ret < 0)
  56                return ret;
  57
  58        return (buf_rx[0] << 8) |  buf_rx[1];
  59}
  60
  61static int read24(void *client, u8 reg)
  62{
  63        int ret;
  64        u8 buf_rx[3];
  65
  66        write24(client, reg, 0);
  67        ret = spi_read(client, buf_rx, 3);
  68        if (ret < 0)
  69                return ret;
  70
  71        return (buf_rx[1] << 8) |  buf_rx[2];
  72}
  73
  74static const struct ad_dpot_bus_ops bops = {
  75        .read_d8        = read8,
  76        .read_r8d8      = read16,
  77        .read_r8d16     = read24,
  78        .write_d8       = write8,
  79        .write_r8d8     = write16,
  80        .write_r8d16    = write24,
  81};
  82static int ad_dpot_spi_probe(struct spi_device *spi)
  83{
  84        struct ad_dpot_bus_data bdata = {
  85                .client = spi,
  86                .bops = &bops,
  87        };
  88
  89        return ad_dpot_probe(&spi->dev, &bdata,
  90                             spi_get_device_id(spi)->driver_data,
  91                             spi_get_device_id(spi)->name);
  92}
  93
  94static int ad_dpot_spi_remove(struct spi_device *spi)
  95{
  96        return ad_dpot_remove(&spi->dev);
  97}
  98
  99static const struct spi_device_id ad_dpot_spi_id[] = {
 100        {"ad5160", AD5160_ID},
 101        {"ad5161", AD5161_ID},
 102        {"ad5162", AD5162_ID},
 103        {"ad5165", AD5165_ID},
 104        {"ad5200", AD5200_ID},
 105        {"ad5201", AD5201_ID},
 106        {"ad5203", AD5203_ID},
 107        {"ad5204", AD5204_ID},
 108        {"ad5206", AD5206_ID},
 109        {"ad5207", AD5207_ID},
 110        {"ad5231", AD5231_ID},
 111        {"ad5232", AD5232_ID},
 112        {"ad5233", AD5233_ID},
 113        {"ad5235", AD5235_ID},
 114        {"ad5260", AD5260_ID},
 115        {"ad5262", AD5262_ID},
 116        {"ad5263", AD5263_ID},
 117        {"ad5290", AD5290_ID},
 118        {"ad5291", AD5291_ID},
 119        {"ad5292", AD5292_ID},
 120        {"ad5293", AD5293_ID},
 121        {"ad7376", AD7376_ID},
 122        {"ad8400", AD8400_ID},
 123        {"ad8402", AD8402_ID},
 124        {"ad8403", AD8403_ID},
 125        {"adn2850", ADN2850_ID},
 126        {"ad5270", AD5270_ID},
 127        {"ad5271", AD5271_ID},
 128        {}
 129};
 130MODULE_DEVICE_TABLE(spi, ad_dpot_spi_id);
 131
 132static struct spi_driver ad_dpot_spi_driver = {
 133        .driver = {
 134                .name   = "ad_dpot",
 135        },
 136        .probe          = ad_dpot_spi_probe,
 137        .remove         = ad_dpot_spi_remove,
 138        .id_table       = ad_dpot_spi_id,
 139};
 140
 141module_spi_driver(ad_dpot_spi_driver);
 142
 143MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
 144MODULE_DESCRIPTION("digital potentiometer SPI bus driver");
 145MODULE_LICENSE("GPL");
 146MODULE_ALIAS("spi:ad_dpot");
 147