drivers/mfd/da9052-i2c.c

   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 MODULE_DEVICE_TABLE(i2c, da9052_i2c_id);
 117
 118 #ifdef CONFIG_OF
 119 static const struct of_device_id dialog_dt_ids[] = {
 120         { .compatible = "dlg,da9052", .data = &da9052_i2c_id[0] },
 121         { .compatible = "dlg,da9053-aa", .data = &da9052_i2c_id[1] },
 122         { .compatible = "dlg,da9053-ba", .data = &da9052_i2c_id[2] },
 123         { .compatible = "dlg,da9053-bb", .data = &da9052_i2c_id[3] },
 124         { .compatible = "dlg,da9053-bc", .data = &da9052_i2c_id[4] },
 125         { /* sentinel */ }
 126 };
 127 #endif
 128
 129 static int da9052_i2c_probe(struct i2c_client *client,
 130                                        const struct i2c_device_id *id)
 131 {
 132         struct da9052 *da9052;
 133         int ret;
 134
 135         da9052 = devm_kzalloc(&client->dev, sizeof(struct da9052), GFP_KERNEL);
 136         if (!da9052)
 137                 return -ENOMEM;
 138
 139         da9052->dev = &client->dev;
 140         da9052->chip_irq = client->irq;
 141         da9052->fix_io = da9052_i2c_fix;
 142
 143         i2c_set_clientdata(client, da9052);
 144
 145         da9052->regmap = devm_regmap_init_i2c(client, &da9052_regmap_config);
 146         if (IS_ERR(da9052->regmap)) {
 147                 ret = PTR_ERR(da9052->regmap);
 148                 dev_err(&client->dev, "Failed to allocate register map: %d\n",
 149                         ret);
 150                 return ret;
 151         }
 152
 153         ret = da9052_i2c_disable_multiwrite(da9052);
 154         if (ret < 0)
 155                 return ret;
 156
 157 #ifdef CONFIG_OF
 158         if (!id) {
 159                 struct device_node *np = client->dev.of_node;
 160                 const struct of_device_id *deviceid;
 161
 162                 deviceid = of_match_node(dialog_dt_ids, np);
 163                 id = deviceid->data;
 164         }
 165 #endif
 166
 167         if (!id) {
 168                 ret = -ENODEV;
 169                 dev_err(&client->dev, "id is null.\n");
 170                 return ret;
 171         }
 172
 173         return da9052_device_init(da9052, id->driver_data);
 174 }
 175
 176 static int da9052_i2c_remove(struct i2c_client *client)
 177 {
 178         struct da9052 *da9052 = i2c_get_clientdata(client);
 179
 180         da9052_device_exit(da9052);
 181         return 0;
 182 }
 183
 184 static struct i2c_driver da9052_i2c_driver = {
 185         .probe = da9052_i2c_probe,
 186         .remove = da9052_i2c_remove,
 187         .id_table = da9052_i2c_id,
 188         .driver = {
 189                 .name = "da9052",
 190 #ifdef CONFIG_OF
 191                 .of_match_table = dialog_dt_ids,
 192 #endif
 193         },
 194 };
 195
 196 static int __init da9052_i2c_init(void)
 197 {
 198         int ret;
 199
 200         ret = i2c_add_driver(&da9052_i2c_driver);
 201         if (ret != 0) {
 202                 pr_err("DA9052 I2C registration failed %d\n", ret);
 203                 return ret;
 204         }
 205
 206         return 0;
 207 }
 208 subsys_initcall(da9052_i2c_init);
 209
 210 static void __exit da9052_i2c_exit(void)
 211 {
 212         i2c_del_driver(&da9052_i2c_driver);
 213 }
 214 module_exit(da9052_i2c_exit);
 215
 216 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
 217 MODULE_DESCRIPTION("I2C driver for Dialog DA9052 PMIC");
 218 MODULE_LICENSE("GPL");