drivers/mfd/tps65217.c

   1 /*
   2  * tps65217.c
   3  *
   4  * TPS65217 chip family multi-function driver
   5  *
   6  * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation version 2.
  11  *
  12  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
  13  * kind, whether express or implied; without even the implied warranty
  14  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  */
  17
  18 #include <linux/kernel.h>
  19 #include <linux/device.h>
  20 #include <linux/module.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/init.h>
  23 #include <linux/i2c.h>
  24 #include <linux/slab.h>
  25 #include <linux/regmap.h>
  26 #include <linux/err.h>
  27 #include <linux/of.h>
  28 #include <linux/of_device.h>
  29
  30 #include <linux/mfd/core.h>
  31 #include <linux/mfd/tps65217.h>
  32
  33 static struct mfd_cell tps65217s[] = {
  34         {
  35                 .name = "tps65217-pmic",
  36         },
  37 };
  38
  39 /**
  40  * tps65217_reg_read: Read a single tps65217 register.
  41  *
  42  * @tps: Device to read from.
  43  * @reg: Register to read.
  44  * @val: Contians the value
  45  */
  46 int tps65217_reg_read(struct tps65217 *tps, unsigned int reg,
  47                         unsigned int *val)
  48 {
  49         return regmap_read(tps->regmap, reg, val);
  50 }
  51 EXPORT_SYMBOL_GPL(tps65217_reg_read);
  52
  53 /**
  54  * tps65217_reg_write: Write a single tps65217 register.
  55  *
  56  * @tps65217: Device to write to.
  57  * @reg: Register to write to.
  58  * @val: Value to write.
  59  * @level: Password protected level
  60  */
  61 int tps65217_reg_write(struct tps65217 *tps, unsigned int reg,
  62                         unsigned int val, unsigned int level)
  63 {
  64         int ret;
  65         unsigned int xor_reg_val;
  66
  67         switch (level) {
  68         case TPS65217_PROTECT_NONE:
  69                 return regmap_write(tps->regmap, reg, val);
  70         case TPS65217_PROTECT_L1:
  71                 xor_reg_val = reg ^ TPS65217_PASSWORD_REGS_UNLOCK;
  72                 ret = regmap_write(tps->regmap, TPS65217_REG_PASSWORD,
  73                                                         xor_reg_val);
  74                 if (ret < 0)
  75                         return ret;
  76
  77                 return regmap_write(tps->regmap, reg, val);
  78         case TPS65217_PROTECT_L2:
  79                 xor_reg_val = reg ^ TPS65217_PASSWORD_REGS_UNLOCK;
  80                 ret = regmap_write(tps->regmap, TPS65217_REG_PASSWORD,
  81                                                         xor_reg_val);
  82                 if (ret < 0)
  83                         return ret;
  84                 ret = regmap_write(tps->regmap, reg, val);
  85                 if (ret < 0)
  86                         return ret;
  87                 ret = regmap_write(tps->regmap, TPS65217_REG_PASSWORD,
  88                                                         xor_reg_val);
  89                 if (ret < 0)
  90                         return ret;
  91                 return regmap_write(tps->regmap, reg, val);
  92         default:
  93                 return -EINVAL;
  94         }
  95 }
  96 EXPORT_SYMBOL_GPL(tps65217_reg_write);
  97
  98 /**
  99  * tps65217_update_bits: Modify bits w.r.t mask, val and level.
 100  *
 101  * @tps65217: Device to write to.
 102  * @reg: Register to read-write to.
 103  * @mask: Mask.
 104  * @val: Value to write.
 105  * @level: Password protected level
 106  */
 107 static int tps65217_update_bits(struct tps65217 *tps, unsigned int reg,
 108                 unsigned int mask, unsigned int val, unsigned int level)
 109 {
 110         int ret;
 111         unsigned int data;
 112
 113         ret = tps65217_reg_read(tps, reg, &data);
 114         if (ret) {
 115                 dev_err(tps->dev, "Read from reg 0x%x failed\n", reg);
 116                 return ret;
 117         }
 118
 119         data &= ~mask;
 120         data |= val & mask;
 121
 122         ret = tps65217_reg_write(tps, reg, data, level);
 123         if (ret)
 124                 dev_err(tps->dev, "Write for reg 0x%x failed\n", reg);
 125
 126         return ret;
 127 }
 128
 129 int tps65217_set_bits(struct tps65217 *tps, unsigned int reg,
 130                 unsigned int mask, unsigned int val, unsigned int level)
 131 {
 132         return tps65217_update_bits(tps, reg, mask, val, level);
 133 }
 134 EXPORT_SYMBOL_GPL(tps65217_set_bits);
 135
 136 int tps65217_clear_bits(struct tps65217 *tps, unsigned int reg,
 137                 unsigned int mask, unsigned int level)
 138 {
 139         return tps65217_update_bits(tps, reg, mask, 0, level);
 140 }
 141 EXPORT_SYMBOL_GPL(tps65217_clear_bits);
 142
 143 static struct regmap_config tps65217_regmap_config = {
 144         .reg_bits = 8,
 145         .val_bits = 8,
 146 };
 147
 148 static const struct of_device_id tps65217_of_match[] = {
 149         { .compatible = "ti,tps65217", .data = (void *)TPS65217 },
 150         { /* sentinel */ },
 151 };
 152
 153 static int __devinit tps65217_probe(struct i2c_client *client,
 154                                 const struct i2c_device_id *ids)
 155 {
 156         struct tps65217 *tps;
 157         unsigned int version;
 158         unsigned int chip_id = ids->driver_data;
 159         const struct of_device_id *match;
 160         int ret;
 161
 162         if (client->dev.of_node) {
 163                 match = of_match_device(tps65217_of_match, &client->dev);
 164                 if (!match) {
 165                         dev_err(&client->dev,
 166                                 "Failed to find matching dt id\n");
 167                         return -EINVAL;
 168                 }
 169                 chip_id = (unsigned int)match->data;
 170         }
 171
 172         if (!chip_id) {
 173                 dev_err(&client->dev, "id is null.\n");
 174                 return -ENODEV;
 175         }
 176
 177         tps = devm_kzalloc(&client->dev, sizeof(*tps), GFP_KERNEL);
 178         if (!tps)
 179                 return -ENOMEM;
 180
 181         i2c_set_clientdata(client, tps);
 182         tps->dev = &client->dev;
 183         tps->id = chip_id;
 184
 185         tps->regmap = devm_regmap_init_i2c(client, &tps65217_regmap_config);
 186         if (IS_ERR(tps->regmap)) {
 187                 ret = PTR_ERR(tps->regmap);
 188                 dev_err(tps->dev, "Failed to allocate register map: %d\n",
 189                         ret);
 190                 return ret;
 191         }
 192
 193         ret = mfd_add_devices(tps->dev, -1, tps65217s,
 194                               ARRAY_SIZE(tps65217s), NULL, 0, NULL);
 195         if (ret < 0) {
 196                 dev_err(tps->dev, "mfd_add_devices failed: %d\n", ret);
 197                 return ret;
 198         }
 199
 200         ret = tps65217_reg_read(tps, TPS65217_REG_CHIPID, &version);
 201         if (ret < 0) {
 202                 dev_err(tps->dev, "Failed to read revision register: %d\n",
 203                         ret);
 204                 return ret;
 205         }
 206
 207         dev_info(tps->dev, "TPS65217 ID %#x version 1.%d\n",
 208                         (version & TPS65217_CHIPID_CHIP_MASK) >> 4,
 209                         version & TPS65217_CHIPID_REV_MASK);
 210
 211         return 0;
 212 }
 213
 214 static int __devexit tps65217_remove(struct i2c_client *client)
 215 {
 216         struct tps65217 *tps = i2c_get_clientdata(client);
 217
 218         mfd_remove_devices(tps->dev);
 219
 220         return 0;
 221 }
 222
 223 static const struct i2c_device_id tps65217_id_table[] = {
 224         {"tps65217", TPS65217},
 225         { /* sentinel */ }
 226 };
 227 MODULE_DEVICE_TABLE(i2c, tps65217_id_table);
 228
 229 static struct i2c_driver tps65217_driver = {
 230         .driver         = {
 231                 .name   = "tps65217",
 232                 .owner  = THIS_MODULE,
 233                 .of_match_table = of_match_ptr(tps65217_of_match),
 234         },
 235         .id_table       = tps65217_id_table,
 236         .probe          = tps65217_probe,
 237         .remove         = __devexit_p(tps65217_remove),
 238 };
 239
 240 static int __init tps65217_init(void)
 241 {
 242         return i2c_add_driver(&tps65217_driver);
 243 }
 244 subsys_initcall(tps65217_init);
 245
 246 static void __exit tps65217_exit(void)
 247 {
 248         i2c_del_driver(&tps65217_driver);
 249 }
 250 module_exit(tps65217_exit);
 251
 252 MODULE_AUTHOR("AnilKumar Ch <anilkumar@ti.com>");
 253 MODULE_DESCRIPTION("TPS65217 chip family multi-function driver");
 254 MODULE_LICENSE("GPL v2");