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