drivers/mfd/88pm860x-i2c.c

   1 /*
   2  * I2C driver for Marvell 88PM860x
   3  *
   4  * Copyright (C) 2009 Marvell International Ltd.
   5  *      Haojian Zhuang <haojian.zhuang@marvell.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/i2c.h>
  15 #include <linux/mfd/88pm860x.h>
  16 #include <linux/slab.h>
  17
  18 static inline int pm860x_read_device(struct i2c_client *i2c,
  19                                      int reg, int bytes, void *dest)
  20 {
  21         unsigned char data;
  22         int ret;
  23
  24         data = (unsigned char)reg;
  25         ret = i2c_master_send(i2c, &data, 1);
  26         if (ret < 0)
  27                 return ret;
  28
  29         ret = i2c_master_recv(i2c, dest, bytes);
  30         if (ret < 0)
  31                 return ret;
  32         return 0;
  33 }
  34
  35 static inline int pm860x_write_device(struct i2c_client *i2c,
  36                                       int reg, int bytes, void *src)
  37 {
  38         unsigned char buf[bytes + 1];
  39         int ret;
  40
  41         buf[0] = (unsigned char)reg;
  42         memcpy(&buf[1], src, bytes);
  43
  44         ret = i2c_master_send(i2c, buf, bytes + 1);
  45         if (ret < 0)
  46                 return ret;
  47         return 0;
  48 }
  49
  50 int pm860x_reg_read(struct i2c_client *i2c, int reg)
  51 {
  52         struct pm860x_chip *chip = i2c_get_clientdata(i2c);
  53         unsigned char data;
  54         int ret;
  55
  56         mutex_lock(&chip->io_lock);
  57         ret = pm860x_read_device(i2c, reg, 1, &data);
  58         mutex_unlock(&chip->io_lock);
  59
  60         if (ret < 0)
  61                 return ret;
  62         else
  63                 return (int)data;
  64 }
  65 EXPORT_SYMBOL(pm860x_reg_read);
  66
  67 int pm860x_reg_write(struct i2c_client *i2c, int reg,
  68                      unsigned char data)
  69 {
  70         struct pm860x_chip *chip = i2c_get_clientdata(i2c);
  71         int ret;
  72
  73         mutex_lock(&chip->io_lock);
  74         ret = pm860x_write_device(i2c, reg, 1, &data);
  75         mutex_unlock(&chip->io_lock);
  76
  77         return ret;
  78 }
  79 EXPORT_SYMBOL(pm860x_reg_write);
  80
  81 int pm860x_bulk_read(struct i2c_client *i2c, int reg,
  82                      int count, unsigned char *buf)
  83 {
  84         struct pm860x_chip *chip = i2c_get_clientdata(i2c);
  85         int ret;
  86
  87         mutex_lock(&chip->io_lock);
  88         ret = pm860x_read_device(i2c, reg, count, buf);
  89         mutex_unlock(&chip->io_lock);
  90
  91         return ret;
  92 }
  93 EXPORT_SYMBOL(pm860x_bulk_read);
  94
  95 int pm860x_bulk_write(struct i2c_client *i2c, int reg,
  96                       int count, unsigned char *buf)
  97 {
  98         struct pm860x_chip *chip = i2c_get_clientdata(i2c);
  99         int ret;
 100
 101         mutex_lock(&chip->io_lock);
 102         ret = pm860x_write_device(i2c, reg, count, buf);
 103         mutex_unlock(&chip->io_lock);
 104
 105         return ret;
 106 }
 107 EXPORT_SYMBOL(pm860x_bulk_write);
 108
 109 int pm860x_set_bits(struct i2c_client *i2c, int reg,
 110                     unsigned char mask, unsigned char data)
 111 {
 112         struct pm860x_chip *chip = i2c_get_clientdata(i2c);
 113         unsigned char value;
 114         int ret;
 115
 116         mutex_lock(&chip->io_lock);
 117         ret = pm860x_read_device(i2c, reg, 1, &value);
 118         if (ret < 0)
 119                 goto out;
 120         value &= ~mask;
 121         value |= data;
 122         ret = pm860x_write_device(i2c, reg, 1, &value);
 123 out:
 124         mutex_unlock(&chip->io_lock);
 125         return ret;
 126 }
 127 EXPORT_SYMBOL(pm860x_set_bits);
 128
 129 int pm860x_page_reg_read(struct i2c_client *i2c, int reg)
 130 {
 131         struct pm860x_chip *chip = i2c_get_clientdata(i2c);
 132         unsigned char zero = 0;
 133         unsigned char data;
 134         int ret;
 135
 136         mutex_lock(&chip->io_lock);
 137         pm860x_write_device(i2c, 0xFA, 0, &zero);
 138         pm860x_write_device(i2c, 0xFB, 0, &zero);
 139         pm860x_write_device(i2c, 0xFF, 0, &zero);
 140         ret = pm860x_read_device(i2c, reg, 1, &data);
 141         if (ret >= 0)
 142                 ret = (int)data;
 143         pm860x_write_device(i2c, 0xFE, 0, &zero);
 144         pm860x_write_device(i2c, 0xFC, 0, &zero);
 145         mutex_unlock(&chip->io_lock);
 146         return ret;
 147 }
 148 EXPORT_SYMBOL(pm860x_page_reg_read);
 149
 150 int pm860x_page_reg_write(struct i2c_client *i2c, int reg,
 151                           unsigned char data)
 152 {
 153         struct pm860x_chip *chip = i2c_get_clientdata(i2c);
 154         unsigned char zero;
 155         int ret;
 156
 157         mutex_lock(&chip->io_lock);
 158         pm860x_write_device(i2c, 0xFA, 0, &zero);
 159         pm860x_write_device(i2c, 0xFB, 0, &zero);
 160         pm860x_write_device(i2c, 0xFF, 0, &zero);
 161         ret = pm860x_write_device(i2c, reg, 1, &data);
 162         pm860x_write_device(i2c, 0xFE, 0, &zero);
 163         pm860x_write_device(i2c, 0xFC, 0, &zero);
 164         mutex_unlock(&chip->io_lock);
 165         return ret;
 166 }
 167 EXPORT_SYMBOL(pm860x_page_reg_write);
 168
 169 int pm860x_page_bulk_read(struct i2c_client *i2c, int reg,
 170                           int count, unsigned char *buf)
 171 {
 172         struct pm860x_chip *chip = i2c_get_clientdata(i2c);
 173         unsigned char zero = 0;
 174         int ret;
 175
 176         mutex_lock(&chip->io_lock);
 177         pm860x_write_device(i2c, 0xFA, 0, &zero);
 178         pm860x_write_device(i2c, 0xFB, 0, &zero);
 179         pm860x_write_device(i2c, 0xFF, 0, &zero);
 180         ret = pm860x_read_device(i2c, reg, count, buf);
 181         pm860x_write_device(i2c, 0xFE, 0, &zero);
 182         pm860x_write_device(i2c, 0xFC, 0, &zero);
 183         mutex_unlock(&chip->io_lock);
 184         return ret;
 185 }
 186 EXPORT_SYMBOL(pm860x_page_bulk_read);
 187
 188 int pm860x_page_bulk_write(struct i2c_client *i2c, int reg,
 189                            int count, unsigned char *buf)
 190 {
 191         struct pm860x_chip *chip = i2c_get_clientdata(i2c);
 192         unsigned char zero = 0;
 193         int ret;
 194
 195         mutex_lock(&chip->io_lock);
 196         pm860x_write_device(i2c, 0xFA, 0, &zero);
 197         pm860x_write_device(i2c, 0xFB, 0, &zero);
 198         pm860x_write_device(i2c, 0xFF, 0, &zero);
 199         ret = pm860x_write_device(i2c, reg, count, buf);
 200         pm860x_write_device(i2c, 0xFE, 0, &zero);
 201         pm860x_write_device(i2c, 0xFC, 0, &zero);
 202         mutex_unlock(&chip->io_lock);
 203         return ret;
 204 }
 205 EXPORT_SYMBOL(pm860x_page_bulk_write);
 206
 207 int pm860x_page_set_bits(struct i2c_client *i2c, int reg,
 208                          unsigned char mask, unsigned char data)
 209 {
 210         struct pm860x_chip *chip = i2c_get_clientdata(i2c);
 211         unsigned char zero;
 212         unsigned char value;
 213         int ret;
 214
 215         mutex_lock(&chip->io_lock);
 216         pm860x_write_device(i2c, 0xFA, 0, &zero);
 217         pm860x_write_device(i2c, 0xFB, 0, &zero);
 218         pm860x_write_device(i2c, 0xFF, 0, &zero);
 219         ret = pm860x_read_device(i2c, reg, 1, &value);
 220         if (ret < 0)
 221                 goto out;
 222         value &= ~mask;
 223         value |= data;
 224         ret = pm860x_write_device(i2c, reg, 1, &value);
 225 out:
 226         pm860x_write_device(i2c, 0xFE, 0, &zero);
 227         pm860x_write_device(i2c, 0xFC, 0, &zero);
 228         mutex_unlock(&chip->io_lock);
 229         return ret;
 230 }
 231 EXPORT_SYMBOL(pm860x_page_set_bits);
 232
 233 static const struct i2c_device_id pm860x_id_table[] = {
 234         { "88PM860x", 0 },
 235         {}
 236 };
 237 MODULE_DEVICE_TABLE(i2c, pm860x_id_table);
 238
 239 static int verify_addr(struct i2c_client *i2c)
 240 {
 241         unsigned short addr_8607[] = {0x30, 0x34};
 242         unsigned short addr_8606[] = {0x10, 0x11};
 243         int size, i;
 244
 245         if (i2c == NULL)
 246                 return 0;
 247         size = ARRAY_SIZE(addr_8606);
 248         for (i = 0; i < size; i++) {
 249                 if (i2c->addr == *(addr_8606 + i))
 250                         return CHIP_PM8606;
 251         }
 252         size = ARRAY_SIZE(addr_8607);
 253         for (i = 0; i < size; i++) {
 254                 if (i2c->addr == *(addr_8607 + i))
 255                         return CHIP_PM8607;
 256         }
 257         return 0;
 258 }
 259
 260 static int __devinit pm860x_probe(struct i2c_client *client,
 261                                   const struct i2c_device_id *id)
 262 {
 263         struct pm860x_platform_data *pdata = client->dev.platform_data;
 264         struct pm860x_chip *chip;
 265
 266         if (!pdata) {
 267                 pr_info("No platform data in %s!\n", __func__);
 268                 return -EINVAL;
 269         }
 270
 271         chip = kzalloc(sizeof(struct pm860x_chip), GFP_KERNEL);
 272         if (chip == NULL)
 273                 return -ENOMEM;
 274
 275         chip->id = verify_addr(client);
 276         chip->client = client;
 277         i2c_set_clientdata(client, chip);
 278         chip->dev = &client->dev;
 279         mutex_init(&chip->io_lock);
 280         dev_set_drvdata(chip->dev, chip);
 281
 282         /*
 283          * Both client and companion client shares same platform driver.
 284          * Driver distinguishes them by pdata->companion_addr.
 285          * pdata->companion_addr is only assigned if companion chip exists.
 286          * At the same time, the companion_addr shouldn't equal to client
 287          * address.
 288          */
 289         if (pdata->companion_addr && (pdata->companion_addr != client->addr)) {
 290                 chip->companion_addr = pdata->companion_addr;
 291                 chip->companion = i2c_new_dummy(chip->client->adapter,
 292                                                 chip->companion_addr);
 293                 i2c_set_clientdata(chip->companion, chip);
 294         }
 295
 296         pm860x_device_init(chip, pdata);
 297         return 0;
 298 }
 299
 300 static int __devexit pm860x_remove(struct i2c_client *client)
 301 {
 302         struct pm860x_chip *chip = i2c_get_clientdata(client);
 303
 304         pm860x_device_exit(chip);
 305         i2c_unregister_device(chip->companion);
 306         kfree(chip);
 307         return 0;
 308 }
 309
 310 static struct i2c_driver pm860x_driver = {
 311         .driver = {
 312                 .name   = "88PM860x",
 313                 .owner  = THIS_MODULE,
 314         },
 315         .probe          = pm860x_probe,
 316         .remove         = __devexit_p(pm860x_remove),
 317         .id_table       = pm860x_id_table,
 318 };
 319
 320 static int __init pm860x_i2c_init(void)
 321 {
 322         int ret;
 323         ret = i2c_add_driver(&pm860x_driver);
 324         if (ret != 0)
 325                 pr_err("Failed to register 88PM860x I2C driver: %d\n", ret);
 326         return ret;
 327 }
 328 subsys_initcall(pm860x_i2c_init);
 329
 330 static void __exit pm860x_i2c_exit(void)
 331 {
 332         i2c_del_driver(&pm860x_driver);
 333 }
 334 module_exit(pm860x_i2c_exit);
 335
 336 MODULE_DESCRIPTION("I2C Driver for Marvell 88PM860x");
 337 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
 338 MODULE_LICENSE("GPL");