drivers/mfd/da9052-i2c.c

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This source file includes following definitions.
i2c_safe_reg
da9052_i2c_fix
da9052_i2c_disable_multiwrite
da9052_i2c_probe
da9052_i2c_remove
da9052_i2c_init
da9052_i2c_exit
   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * I2C access for DA9052 PMICs.
   4  *
   5  * Copyright(c) 2011 Dialog Semiconductor Ltd.
   6  *
   7  * Author: David Dajun Chen <dchen@diasemi.com>
   8  */
   9 
  10 #include <linux/device.h>
  11 #include <linux/module.h>
  12 #include <linux/input.h>
  13 #include <linux/mfd/core.h>
  14 #include <linux/i2c.h>
  15 #include <linux/err.h>
  16 
  17 #include <linux/mfd/da9052/da9052.h>
  18 #include <linux/mfd/da9052/reg.h>
  19 
  20 #ifdef CONFIG_OF
  21 #include <linux/of.h>
  22 #include <linux/of_device.h>
  23 #endif
  24 
  25 /* I2C safe register check */
  26 static inline bool i2c_safe_reg(unsigned char reg)
  27 {
  28         switch (reg) {
  29         case DA9052_STATUS_A_REG:
  30         case DA9052_STATUS_B_REG:
  31         case DA9052_STATUS_C_REG:
  32         case DA9052_STATUS_D_REG:
  33         case DA9052_ADC_RES_L_REG:
  34         case DA9052_ADC_RES_H_REG:
  35         case DA9052_VDD_RES_REG:
  36         case DA9052_ICHG_AV_REG:
  37         case DA9052_TBAT_RES_REG:
  38         case DA9052_ADCIN4_RES_REG:
  39         case DA9052_ADCIN5_RES_REG:
  40         case DA9052_ADCIN6_RES_REG:
  41         case DA9052_TJUNC_RES_REG:
  42         case DA9052_TSI_X_MSB_REG:
  43         case DA9052_TSI_Y_MSB_REG:
  44         case DA9052_TSI_LSB_REG:
  45         case DA9052_TSI_Z_MSB_REG:
  46                 return true;
  47         default:
  48                 return false;
  49         }
  50 }
  51 
  52 /*
  53  * There is an issue with DA9052 and DA9053_AA/BA/BB PMIC where the PMIC
  54  * gets lockup up or fails to respond following a system reset.
  55  * This fix is to follow any read or write with a dummy read to a safe
  56  * register.
  57  */
  58 static int da9052_i2c_fix(struct da9052 *da9052, unsigned char reg)
  59 {
  60         int val;
  61 
  62         switch (da9052->chip_id) {
  63         case DA9052:
  64         case DA9053_AA:
  65         case DA9053_BA:
  66         case DA9053_BB:
  67                 /* A dummy read to a safe register address. */
  68                 if (!i2c_safe_reg(reg))
  69                         return regmap_read(da9052->regmap,
  70                                            DA9052_PARK_REGISTER,
  71                                            &val);
  72                 break;
  73         case DA9053_BC:
  74         default:
  75                 /*
  76                  * For other chips parking of I2C register
  77                  * to a safe place is not required.
  78                  */
  79                 break;
  80         }
  81 
  82         return 0;
  83 }
  84 
  85 /*
  86  * According to errata item 24, multiwrite mode should be avoided
  87  * in order to prevent register data corruption after power-down.
  88  */
  89 static int da9052_i2c_disable_multiwrite(struct da9052 *da9052)
  90 {
  91         int reg_val, ret;
  92 
  93         ret = regmap_read(da9052->regmap, DA9052_CONTROL_B_REG, &reg_val);
  94         if (ret < 0)
  95                 return ret;
  96 
  97         if (!(reg_val & DA9052_CONTROL_B_WRITEMODE)) {
  98                 reg_val |= DA9052_CONTROL_B_WRITEMODE;
  99                 ret = regmap_write(da9052->regmap, DA9052_CONTROL_B_REG,
 100                                    reg_val);
 101                 if (ret < 0)
 102                         return ret;
 103         }
 104 
 105         return 0;
 106 }
 107 
 108 static const struct i2c_device_id da9052_i2c_id[] = {
 109         {"da9052", DA9052},
 110         {"da9053-aa", DA9053_AA},
 111         {"da9053-ba", DA9053_BA},
 112         {"da9053-bb", DA9053_BB},
 113         {"da9053-bc", DA9053_BC},
 114         {}
 115 };
 116 
 117 #ifdef CONFIG_OF
 118 static const struct of_device_id dialog_dt_ids[] = {
 119         { .compatible = "dlg,da9052", .data = &da9052_i2c_id[0] },
 120         { .compatible = "dlg,da9053-aa", .data = &da9052_i2c_id[1] },
 121         { .compatible = "dlg,da9053-ba", .data = &da9052_i2c_id[2] },
 122         { .compatible = "dlg,da9053-bb", .data = &da9052_i2c_id[3] },
 123         { .compatible = "dlg,da9053-bc", .data = &da9052_i2c_id[4] },
 124         { /* sentinel */ }
 125 };
 126 #endif
 127 
 128 static int da9052_i2c_probe(struct i2c_client *client,
 129                                        const struct i2c_device_id *id)
 130 {
 131         struct da9052 *da9052;
 132         int ret;
 133 
 134         da9052 = devm_kzalloc(&client->dev, sizeof(struct da9052), GFP_KERNEL);
 135         if (!da9052)
 136                 return -ENOMEM;
 137 
 138         da9052->dev = &client->dev;
 139         da9052->chip_irq = client->irq;
 140         da9052->fix_io = da9052_i2c_fix;
 141 
 142         i2c_set_clientdata(client, da9052);
 143 
 144         da9052->regmap = devm_regmap_init_i2c(client, &da9052_regmap_config);
 145         if (IS_ERR(da9052->regmap)) {
 146                 ret = PTR_ERR(da9052->regmap);
 147                 dev_err(&client->dev, "Failed to allocate register map: %d\n",
 148                         ret);
 149                 return ret;
 150         }
 151 
 152         ret = da9052_i2c_disable_multiwrite(da9052);
 153         if (ret < 0)
 154                 return ret;
 155 
 156 #ifdef CONFIG_OF
 157         if (!id) {
 158                 struct device_node *np = client->dev.of_node;
 159                 const struct of_device_id *deviceid;
 160 
 161                 deviceid = of_match_node(dialog_dt_ids, np);
 162                 id = deviceid->data;
 163         }
 164 #endif
 165 
 166         if (!id) {
 167                 ret = -ENODEV;
 168                 dev_err(&client->dev, "id is null.\n");
 169                 return ret;
 170         }
 171 
 172         return da9052_device_init(da9052, id->driver_data);
 173 }
 174 
 175 static int da9052_i2c_remove(struct i2c_client *client)
 176 {
 177         struct da9052 *da9052 = i2c_get_clientdata(client);
 178 
 179         da9052_device_exit(da9052);
 180         return 0;
 181 }
 182 
 183 static struct i2c_driver da9052_i2c_driver = {
 184         .probe = da9052_i2c_probe,
 185         .remove = da9052_i2c_remove,
 186         .id_table = da9052_i2c_id,
 187         .driver = {
 188                 .name = "da9052",
 189 #ifdef CONFIG_OF
 190                 .of_match_table = dialog_dt_ids,
 191 #endif
 192         },
 193 };
 194 
 195 static int __init da9052_i2c_init(void)
 196 {
 197         int ret;
 198 
 199         ret = i2c_add_driver(&da9052_i2c_driver);
 200         if (ret != 0) {
 201                 pr_err("DA9052 I2C registration failed %d\n", ret);
 202                 return ret;
 203         }
 204 
 205         return 0;
 206 }
 207 subsys_initcall(da9052_i2c_init);
 208 
 209 static void __exit da9052_i2c_exit(void)
 210 {
 211         i2c_del_driver(&da9052_i2c_driver);
 212 }
 213 module_exit(da9052_i2c_exit);
 214 
 215 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
 216 MODULE_DESCRIPTION("I2C driver for Dialog DA9052 PMIC");
 217 MODULE_LICENSE("GPL");
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/mfd/da9052-i2c.c

DEFINITIONS
