drivers/mfd/as3711.c

   1 /*
   2  * AS3711 PMIC MFC driver
   3  *
   4  * Copyright (C) 2012 Renesas Electronics Corporation
   5  * Author: Guennadi Liakhovetski, <g.liakhovetski@gmx.de>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the version 2 of the GNU General Public License as
   9  * published by the Free Software Foundation
  10  */
  11
  12 #include <linux/device.h>
  13 #include <linux/err.h>
  14 #include <linux/i2c.h>
  15 #include <linux/init.h>
  16 #include <linux/kernel.h>
  17 #include <linux/mfd/as3711.h>
  18 #include <linux/mfd/core.h>
  19 #include <linux/module.h>
  20 #include <linux/of.h>
  21 #include <linux/regmap.h>
  22 #include <linux/slab.h>
  23
  24 enum {
  25         AS3711_REGULATOR,
  26         AS3711_BACKLIGHT,
  27 };
  28
  29 /*
  30  * Ok to have it static: it is only used during probing and multiple I2C devices
  31  * cannot be probed simultaneously. Just make sure to avoid stale data.
  32  */
  33 static struct mfd_cell as3711_subdevs[] = {
  34         [AS3711_REGULATOR] = {.name = "as3711-regulator",},
  35         [AS3711_BACKLIGHT] = {.name = "as3711-backlight",},
  36 };
  37
  38 static bool as3711_volatile_reg(struct device *dev, unsigned int reg)
  39 {
  40         switch (reg) {
  41         case AS3711_GPIO_SIGNAL_IN:
  42         case AS3711_INTERRUPT_STATUS_1:
  43         case AS3711_INTERRUPT_STATUS_2:
  44         case AS3711_INTERRUPT_STATUS_3:
  45         case AS3711_CHARGER_STATUS_1:
  46         case AS3711_CHARGER_STATUS_2:
  47         case AS3711_REG_STATUS:
  48                 return true;
  49         }
  50         return false;
  51 }
  52
  53 static bool as3711_precious_reg(struct device *dev, unsigned int reg)
  54 {
  55         switch (reg) {
  56         case AS3711_INTERRUPT_STATUS_1:
  57         case AS3711_INTERRUPT_STATUS_2:
  58         case AS3711_INTERRUPT_STATUS_3:
  59                 return true;
  60         }
  61         return false;
  62 }
  63
  64 static bool as3711_readable_reg(struct device *dev, unsigned int reg)
  65 {
  66         switch (reg) {
  67         case AS3711_SD_1_VOLTAGE:
  68         case AS3711_SD_2_VOLTAGE:
  69         case AS3711_SD_3_VOLTAGE:
  70         case AS3711_SD_4_VOLTAGE:
  71         case AS3711_LDO_1_VOLTAGE:
  72         case AS3711_LDO_2_VOLTAGE:
  73         case AS3711_LDO_3_VOLTAGE:
  74         case AS3711_LDO_4_VOLTAGE:
  75         case AS3711_LDO_5_VOLTAGE:
  76         case AS3711_LDO_6_VOLTAGE:
  77         case AS3711_LDO_7_VOLTAGE:
  78         case AS3711_LDO_8_VOLTAGE:
  79         case AS3711_SD_CONTROL:
  80         case AS3711_GPIO_SIGNAL_OUT:
  81         case AS3711_GPIO_SIGNAL_IN:
  82         case AS3711_SD_CONTROL_1:
  83         case AS3711_SD_CONTROL_2:
  84         case AS3711_CURR_CONTROL:
  85         case AS3711_CURR1_VALUE:
  86         case AS3711_CURR2_VALUE:
  87         case AS3711_CURR3_VALUE:
  88         case AS3711_STEPUP_CONTROL_1:
  89         case AS3711_STEPUP_CONTROL_2:
  90         case AS3711_STEPUP_CONTROL_4:
  91         case AS3711_STEPUP_CONTROL_5:
  92         case AS3711_REG_STATUS:
  93         case AS3711_INTERRUPT_STATUS_1:
  94         case AS3711_INTERRUPT_STATUS_2:
  95         case AS3711_INTERRUPT_STATUS_3:
  96         case AS3711_CHARGER_STATUS_1:
  97         case AS3711_CHARGER_STATUS_2:
  98         case AS3711_ASIC_ID_1:
  99         case AS3711_ASIC_ID_2:
 100                 return true;
 101         }
 102         return false;
 103 }
 104
 105 static const struct regmap_config as3711_regmap_config = {
 106         .reg_bits = 8,
 107         .val_bits = 8,
 108         .volatile_reg = as3711_volatile_reg,
 109         .readable_reg = as3711_readable_reg,
 110         .precious_reg = as3711_precious_reg,
 111         .max_register = AS3711_MAX_REG,
 112         .num_reg_defaults_raw = AS3711_NUM_REGS,
 113         .cache_type = REGCACHE_RBTREE,
 114 };
 115
 116 #ifdef CONFIG_OF
 117 static const struct of_device_id as3711_of_match[] = {
 118         {.compatible = "ams,as3711",},
 119         {}
 120 };
 121 MODULE_DEVICE_TABLE(of, as3711_of_match);
 122 #endif
 123
 124 static int as3711_i2c_probe(struct i2c_client *client,
 125                             const struct i2c_device_id *id)
 126 {
 127         struct as3711 *as3711;
 128         struct as3711_platform_data *pdata;
 129         unsigned int id1, id2;
 130         int ret;
 131
 132         if (!client->dev.of_node) {
 133                 pdata = dev_get_platdata(&client->dev);
 134                 if (!pdata)
 135                         dev_dbg(&client->dev, "Platform data not found\n");
 136         } else {
 137                 pdata = devm_kzalloc(&client->dev,
 138                                      sizeof(*pdata), GFP_KERNEL);
 139                 if (!pdata)
 140                         return -ENOMEM;
 141         }
 142
 143         as3711 = devm_kzalloc(&client->dev, sizeof(struct as3711), GFP_KERNEL);
 144         if (!as3711)
 145                 return -ENOMEM;
 146
 147         as3711->dev = &client->dev;
 148         i2c_set_clientdata(client, as3711);
 149
 150         if (client->irq)
 151                 dev_notice(&client->dev, "IRQ not supported yet\n");
 152
 153         as3711->regmap = devm_regmap_init_i2c(client, &as3711_regmap_config);
 154         if (IS_ERR(as3711->regmap)) {
 155                 ret = PTR_ERR(as3711->regmap);
 156                 dev_err(&client->dev,
 157                         "regmap initialization failed: %d\n", ret);
 158                 return ret;
 159         }
 160
 161         ret = regmap_read(as3711->regmap, AS3711_ASIC_ID_1, &id1);
 162         if (!ret)
 163                 ret = regmap_read(as3711->regmap, AS3711_ASIC_ID_2, &id2);
 164         if (ret < 0) {
 165                 dev_err(&client->dev, "regmap_read() failed: %d\n", ret);
 166                 return ret;
 167         }
 168         if (id1 != 0x8b)
 169                 return -ENODEV;
 170         dev_info(as3711->dev, "AS3711 detected: %x:%x\n", id1, id2);
 171
 172         /*
 173          * We can reuse as3711_subdevs[],
 174          * it will be copied in mfd_add_devices()
 175          */
 176         if (pdata) {
 177                 as3711_subdevs[AS3711_REGULATOR].platform_data =
 178                         &pdata->regulator;
 179                 as3711_subdevs[AS3711_REGULATOR].pdata_size =
 180                         sizeof(pdata->regulator);
 181                 as3711_subdevs[AS3711_BACKLIGHT].platform_data =
 182                         &pdata->backlight;
 183                 as3711_subdevs[AS3711_BACKLIGHT].pdata_size =
 184                         sizeof(pdata->backlight);
 185         } else {
 186                 as3711_subdevs[AS3711_REGULATOR].platform_data = NULL;
 187                 as3711_subdevs[AS3711_REGULATOR].pdata_size = 0;
 188                 as3711_subdevs[AS3711_BACKLIGHT].platform_data = NULL;
 189                 as3711_subdevs[AS3711_BACKLIGHT].pdata_size = 0;
 190         }
 191
 192         ret = devm_mfd_add_devices(as3711->dev, -1, as3711_subdevs,
 193                                    ARRAY_SIZE(as3711_subdevs), NULL, 0, NULL);
 194         if (ret < 0)
 195                 dev_err(&client->dev, "add mfd devices failed: %d\n", ret);
 196
 197         return ret;
 198 }
 199
 200 static const struct i2c_device_id as3711_i2c_id[] = {
 201         {.name = "as3711", .driver_data = 0},
 202         {}
 203 };
 204
 205 MODULE_DEVICE_TABLE(i2c, as3711_i2c_id);
 206
 207 static struct i2c_driver as3711_i2c_driver = {
 208         .driver = {
 209                    .name = "as3711",
 210                    .of_match_table = of_match_ptr(as3711_of_match),
 211         },
 212         .probe = as3711_i2c_probe,
 213         .id_table = as3711_i2c_id,
 214 };
 215
 216 static int __init as3711_i2c_init(void)
 217 {
 218         return i2c_add_driver(&as3711_i2c_driver);
 219 }
 220 /* Initialise early */
 221 subsys_initcall(as3711_i2c_init);
 222
 223 static void __exit as3711_i2c_exit(void)
 224 {
 225         i2c_del_driver(&as3711_i2c_driver);
 226 }
 227 module_exit(as3711_i2c_exit);
 228
 229 MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
 230 MODULE_DESCRIPTION("AS3711 PMIC driver");
 231 MODULE_LICENSE("GPL v2");