LXR linux/drivers/w1/slaves/w1

   1/*
   2 * 1-Wire implementation for the ds2780 chip
   3 *
   4 * Copyright (C) 2010 Indesign, LLC
   5 *
   6 * Author: Clifton Barnes <cabarnes@indesign-llc.com>
   7 *
   8 * Based on w1-ds2760 driver
   9 *
  10 * This program is free software; you can redistribute it and/or modify
  11 * it under the terms of the GNU General Public License version 2 as
  12 * published by the Free Software Foundation.
  13 *
  14 */
  15
  16#include <linux/kernel.h>
  17#include <linux/module.h>
  18#include <linux/device.h>
  19#include <linux/types.h>
  20#include <linux/platform_device.h>
  21#include <linux/mutex.h>
  22#include <linux/idr.h>
  23
  24#include "../w1.h"
  25#include "../w1_int.h"
  26#include "../w1_family.h"
  27#include "w1_ds2780.h"
  28
  29static int w1_ds2780_do_io(struct device *dev, char *buf, int addr,
  30                        size_t count, int io)
  31{
  32        struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
  33
  34        if (addr > DS2780_DATA_SIZE || addr < 0)
  35                return 0;
  36
  37        count = min_t(int, count, DS2780_DATA_SIZE - addr);
  38
  39        if (w1_reset_select_slave(sl) == 0) {
  40                if (io) {
  41                        w1_write_8(sl->master, W1_DS2780_WRITE_DATA);
  42                        w1_write_8(sl->master, addr);
  43                        w1_write_block(sl->master, buf, count);
  44                } else {
  45                        w1_write_8(sl->master, W1_DS2780_READ_DATA);
  46                        w1_write_8(sl->master, addr);
  47                        count = w1_read_block(sl->master, buf, count);
  48                }
  49        }
  50
  51        return count;
  52}
  53
  54int w1_ds2780_io(struct device *dev, char *buf, int addr, size_t count,
  55                        int io)
  56{
  57        struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
  58        int ret;
  59
  60        if (!dev)
  61                return -ENODEV;
  62
  63        mutex_lock(&sl->master->bus_mutex);
  64
  65        ret = w1_ds2780_do_io(dev, buf, addr, count, io);
  66
  67        mutex_unlock(&sl->master->bus_mutex);
  68
  69        return ret;
  70}
  71EXPORT_SYMBOL(w1_ds2780_io);
  72
  73int w1_ds2780_eeprom_cmd(struct device *dev, int addr, int cmd)
  74{
  75        struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
  76
  77        if (!dev)
  78                return -EINVAL;
  79
  80        mutex_lock(&sl->master->bus_mutex);
  81
  82        if (w1_reset_select_slave(sl) == 0) {
  83                w1_write_8(sl->master, cmd);
  84                w1_write_8(sl->master, addr);
  85        }
  86
  87        mutex_unlock(&sl->master->bus_mutex);
  88        return 0;
  89}
  90EXPORT_SYMBOL(w1_ds2780_eeprom_cmd);
  91
  92static ssize_t w1_slave_read(struct file *filp, struct kobject *kobj,
  93                             struct bin_attribute *bin_attr, char *buf,
  94                             loff_t off, size_t count)
  95{
  96        struct device *dev = container_of(kobj, struct device, kobj);
  97        return w1_ds2780_io(dev, buf, off, count, 0);
  98}
  99
 100static BIN_ATTR_RO(w1_slave, DS2780_DATA_SIZE);
 101
 102static struct bin_attribute *w1_ds2780_bin_attrs[] = {
 103        &bin_attr_w1_slave,
 104        NULL,
 105};
 106
 107static const struct attribute_group w1_ds2780_group = {
 108        .bin_attrs = w1_ds2780_bin_attrs,
 109};
 110
 111static const struct attribute_group *w1_ds2780_groups[] = {
 112        &w1_ds2780_group,
 113        NULL,
 114};
 115
 116static int w1_ds2780_add_slave(struct w1_slave *sl)
 117{
 118        int ret;
 119        struct platform_device *pdev;
 120
 121        pdev = platform_device_alloc("ds2780-battery", PLATFORM_DEVID_AUTO);
 122        if (!pdev)
 123                return -ENOMEM;
 124        pdev->dev.parent = &sl->dev;
 125
 126        ret = platform_device_add(pdev);
 127        if (ret)
 128                goto pdev_add_failed;
 129
 130        dev_set_drvdata(&sl->dev, pdev);
 131
 132        return 0;
 133
 134pdev_add_failed:
 135        platform_device_put(pdev);
 136
 137        return ret;
 138}
 139
 140static void w1_ds2780_remove_slave(struct w1_slave *sl)
 141{
 142        struct platform_device *pdev = dev_get_drvdata(&sl->dev);
 143
 144        platform_device_unregister(pdev);
 145}
 146
 147static struct w1_family_ops w1_ds2780_fops = {
 148        .add_slave    = w1_ds2780_add_slave,
 149        .remove_slave = w1_ds2780_remove_slave,
 150        .groups       = w1_ds2780_groups,
 151};
 152
 153static struct w1_family w1_ds2780_family = {
 154        .fid = W1_FAMILY_DS2780,
 155        .fops = &w1_ds2780_fops,
 156};
 157module_w1_family(w1_ds2780_family);
 158
 159MODULE_LICENSE("GPL");
 160MODULE_AUTHOR("Clifton Barnes <cabarnes@indesign-llc.com>");
 161MODULE_DESCRIPTION("1-wire Driver for Maxim/Dallas DS2780 Stand-Alone Fuel Gauge IC");
 162MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_DS2780));
 163