LXR linux/drivers/mfd/tps6507x.c

   1/*
   2 * tps6507x.c  --  TPS6507x chip family multi-function driver
   3 *
   4 *  Copyright (c) 2010 RidgeRun (todd.fischer@ridgerun.com)
   5 *
   6 * Author: Todd Fischer
   7 *         todd.fischer@ridgerun.com
   8 *
   9 * Credits:
  10 *
  11 *    Using code from wm831x-*.c, wm8400-core, Wolfson Microelectronics PLC.
  12 *
  13 * For licencing details see kernel-base/COPYING
  14 *
  15 */
  16
  17#include <linux/module.h>
  18#include <linux/moduleparam.h>
  19#include <linux/init.h>
  20#include <linux/slab.h>
  21#include <linux/i2c.h>
  22#include <linux/of_device.h>
  23#include <linux/mfd/core.h>
  24#include <linux/mfd/tps6507x.h>
  25
  26static struct mfd_cell tps6507x_devs[] = {
  27        {
  28                .name = "tps6507x-pmic",
  29        },
  30        {
  31                .name = "tps6507x-ts",
  32        },
  33};
  34
  35
  36static int tps6507x_i2c_read_device(struct tps6507x_dev *tps6507x, char reg,
  37                                  int bytes, void *dest)
  38{
  39        struct i2c_client *i2c = tps6507x->i2c_client;
  40        struct i2c_msg xfer[2];
  41        int ret;
  42
  43        /* Write register */
  44        xfer[0].addr = i2c->addr;
  45        xfer[0].flags = 0;
  46        xfer[0].len = 1;
  47        xfer[0].buf = &reg;
  48
  49        /* Read data */
  50        xfer[1].addr = i2c->addr;
  51        xfer[1].flags = I2C_M_RD;
  52        xfer[1].len = bytes;
  53        xfer[1].buf = dest;
  54
  55        ret = i2c_transfer(i2c->adapter, xfer, 2);
  56        if (ret == 2)
  57                ret = 0;
  58        else if (ret >= 0)
  59                ret = -EIO;
  60
  61        return ret;
  62}
  63
  64static int tps6507x_i2c_write_device(struct tps6507x_dev *tps6507x, char reg,
  65                                   int bytes, void *src)
  66{
  67        struct i2c_client *i2c = tps6507x->i2c_client;
  68        /* we add 1 byte for device register */
  69        u8 msg[TPS6507X_MAX_REGISTER + 1];
  70        int ret;
  71
  72        if (bytes > TPS6507X_MAX_REGISTER)
  73                return -EINVAL;
  74
  75        msg[0] = reg;
  76        memcpy(&msg[1], src, bytes);
  77
  78        ret = i2c_master_send(i2c, msg, bytes + 1);
  79        if (ret < 0)
  80                return ret;
  81        if (ret != bytes + 1)
  82                return -EIO;
  83        return 0;
  84}
  85
  86static int tps6507x_i2c_probe(struct i2c_client *i2c,
  87                            const struct i2c_device_id *id)
  88{
  89        struct tps6507x_dev *tps6507x;
  90
  91        tps6507x = devm_kzalloc(&i2c->dev, sizeof(struct tps6507x_dev),
  92                                GFP_KERNEL);
  93        if (tps6507x == NULL)
  94                return -ENOMEM;
  95
  96        i2c_set_clientdata(i2c, tps6507x);
  97        tps6507x->dev = &i2c->dev;
  98        tps6507x->i2c_client = i2c;
  99        tps6507x->read_dev = tps6507x_i2c_read_device;
 100        tps6507x->write_dev = tps6507x_i2c_write_device;
 101
 102        return mfd_add_devices(tps6507x->dev, -1, tps6507x_devs,
 103                               ARRAY_SIZE(tps6507x_devs), NULL, 0, NULL);
 104}
 105
 106static int tps6507x_i2c_remove(struct i2c_client *i2c)
 107{
 108        struct tps6507x_dev *tps6507x = i2c_get_clientdata(i2c);
 109
 110        mfd_remove_devices(tps6507x->dev);
 111        return 0;
 112}
 113
 114static const struct i2c_device_id tps6507x_i2c_id[] = {
 115       { "tps6507x", 0 },
 116       { }
 117};
 118MODULE_DEVICE_TABLE(i2c, tps6507x_i2c_id);
 119
 120#ifdef CONFIG_OF
 121static struct of_device_id tps6507x_of_match[] = {
 122        {.compatible = "ti,tps6507x", },
 123        {},
 124};
 125MODULE_DEVICE_TABLE(of, tps6507x_of_match);
 126#endif
 127
 128static struct i2c_driver tps6507x_i2c_driver = {
 129        .driver = {
 130                   .name = "tps6507x",
 131                   .owner = THIS_MODULE,
 132                   .of_match_table = of_match_ptr(tps6507x_of_match),
 133        },
 134        .probe = tps6507x_i2c_probe,
 135        .remove = tps6507x_i2c_remove,
 136        .id_table = tps6507x_i2c_id,
 137};
 138
 139static int __init tps6507x_i2c_init(void)
 140{
 141        return i2c_add_driver(&tps6507x_i2c_driver);
 142}
 143/* init early so consumer devices can complete system boot */
 144subsys_initcall(tps6507x_i2c_init);
 145
 146static void __exit tps6507x_i2c_exit(void)
 147{
 148        i2c_del_driver(&tps6507x_i2c_driver);
 149}
 150module_exit(tps6507x_i2c_exit);
 151
 152MODULE_DESCRIPTION("TPS6507x chip family multi-function driver");
 153MODULE_LICENSE("GPL");
 154