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 #include <linux/of.h>
  17
  18 #include <linux/mfd/da9052/da9052.h>
  19 #include <linux/mfd/da9052/reg.h>
  20
  21
  22 /* I2C safe register check */
  23 static inline bool i2c_safe_reg(unsigned char reg)
  24 {
  25         switch (reg) {
  26         case DA9052_STATUS_A_REG:
  27         case DA9052_STATUS_B_REG:
  28         case DA9052_STATUS_C_REG:
  29         case DA9052_STATUS_D_REG:
  30         case DA9052_ADC_RES_L_REG:
  31         case DA9052_ADC_RES_H_REG:
  32         case DA9052_VDD_RES_REG:
  33         case DA9052_ICHG_AV_REG:
  34         case DA9052_TBAT_RES_REG:
  35         case DA9052_ADCIN4_RES_REG:
  36         case DA9052_ADCIN5_RES_REG:
  37         case DA9052_ADCIN6_RES_REG:
  38         case DA9052_TJUNC_RES_REG:
  39         case DA9052_TSI_X_MSB_REG:
  40         case DA9052_TSI_Y_MSB_REG:
  41         case DA9052_TSI_LSB_REG:
  42         case DA9052_TSI_Z_MSB_REG:
  43                 return true;
  44         default:
  45                 return false;
  46         }
  47 }
  48
  49 /*
  50  * There is an issue with DA9052 and DA9053_AA/BA/BB PMIC where the PMIC
  51  * gets lockup up or fails to respond following a system reset.
  52  * This fix is to follow any read or write with a dummy read to a safe
  53  * register.
  54  */
  55 static int da9052_i2c_fix(struct da9052 *da9052, unsigned char reg)
  56 {
  57         int val;
  58
  59         switch (da9052->chip_id) {
  60         case DA9052:
  61         case DA9053_AA:
  62         case DA9053_BA:
  63         case DA9053_BB:
  64                 /* A dummy read to a safe register address. */
  65                 if (!i2c_safe_reg(reg))
  66                         return regmap_read(da9052->regmap,
  67                                            DA9052_PARK_REGISTER,
  68                                            &val);
  69                 break;
  70         case DA9053_BC:
  71         default:
  72                 /*
  73                  * For other chips parking of I2C register
  74                  * to a safe place is not required.
  75                  */
  76                 break;
  77         }
  78
  79         return 0;
  80 }
  81
  82 /*
  83  * According to errata item 24, multiwrite mode should be avoided
  84  * in order to prevent register data corruption after power-down.
  85  */
  86 static int da9052_i2c_disable_multiwrite(struct da9052 *da9052)
  87 {
  88         int reg_val, ret;
  89
  90         ret = regmap_read(da9052->regmap, DA9052_CONTROL_B_REG, &reg_val);
  91         if (ret < 0)
  92                 return ret;
  93
  94         if (!(reg_val & DA9052_CONTROL_B_WRITEMODE)) {
  95                 reg_val |= DA9052_CONTROL_B_WRITEMODE;
  96                 ret = regmap_write(da9052->regmap, DA9052_CONTROL_B_REG,
  97                                    reg_val);
  98                 if (ret < 0)
  99                         return ret;
 100         }
 101
 102         return 0;
 103 }
 104
 105 static const struct i2c_device_id da9052_i2c_id[] = {
 106         {"da9052", DA9052},
 107         {"da9053-aa", DA9053_AA},
 108         {"da9053-ba", DA9053_BA},
 109         {"da9053-bb", DA9053_BB},
 110         {"da9053-bc", DA9053_BC},
 111         {}
 112 };
 113 MODULE_DEVICE_TABLE(i2c, da9052_i2c_id);
 114
 115 #ifdef CONFIG_OF
 116 static const struct of_device_id dialog_dt_ids[] = {
 117         { .compatible = "dlg,da9052", .data = &da9052_i2c_id[0] },
 118         { .compatible = "dlg,da9053-aa", .data = &da9052_i2c_id[1] },
 119         { .compatible = "dlg,da9053-ba", .data = &da9052_i2c_id[2] },
 120         { .compatible = "dlg,da9053-bb", .data = &da9052_i2c_id[3] },
 121         { .compatible = "dlg,da9053-bc", .data = &da9052_i2c_id[4] },
 122         { /* sentinel */ }
 123 };
 124 #endif
 125
 126 static int da9052_i2c_probe(struct i2c_client *client)
 127 {
 128         const struct i2c_device_id *id = i2c_client_get_device_id(client);
 129         struct da9052 *da9052;
 130         int ret;
 131
 132         da9052 = devm_kzalloc(&client->dev, sizeof(struct da9052), GFP_KERNEL);
 133         if (!da9052)
 134                 return -ENOMEM;
 135
 136         da9052->dev = &client->dev;
 137         da9052->chip_irq = client->irq;
 138         da9052->fix_io = da9052_i2c_fix;
 139
 140         i2c_set_clientdata(client, da9052);
 141
 142         da9052->regmap = devm_regmap_init_i2c(client, &da9052_regmap_config);
 143         if (IS_ERR(da9052->regmap)) {
 144                 ret = PTR_ERR(da9052->regmap);
 145                 dev_err(&client->dev, "Failed to allocate register map: %d\n",
 146                         ret);
 147                 return ret;
 148         }
 149
 150         ret = da9052_i2c_disable_multiwrite(da9052);
 151         if (ret < 0)
 152                 return ret;
 153
 154 #ifdef CONFIG_OF
 155         if (!id)
 156                 id = of_device_get_match_data(&client->dev);
 157 #endif
 158
 159         if (!id) {
 160                 ret = -ENODEV;
 161                 dev_err(&client->dev, "id is null.\n");
 162                 return ret;
 163         }
 164
 165         return da9052_device_init(da9052, id->driver_data);
 166 }
 167
 168 static void da9052_i2c_remove(struct i2c_client *client)
 169 {
 170         struct da9052 *da9052 = i2c_get_clientdata(client);
 171
 172         da9052_device_exit(da9052);
 173 }
 174
 175 static struct i2c_driver da9052_i2c_driver = {
 176         .probe = da9052_i2c_probe,
 177         .remove = da9052_i2c_remove,
 178         .id_table = da9052_i2c_id,
 179         .driver = {
 180                 .name = "da9052",
 181 #ifdef CONFIG_OF
 182                 .of_match_table = dialog_dt_ids,
 183 #endif
 184         },
 185 };
 186
 187 static int __init da9052_i2c_init(void)
 188 {
 189         int ret;
 190
 191         ret = i2c_add_driver(&da9052_i2c_driver);
 192         if (ret != 0) {
 193                 pr_err("DA9052 I2C registration failed %d\n", ret);
 194                 return ret;
 195         }
 196
 197         return 0;
 198 }
 199 subsys_initcall(da9052_i2c_init);
 200
 201 static void __exit da9052_i2c_exit(void)
 202 {
 203         i2c_del_driver(&da9052_i2c_driver);
 204 }
 205 module_exit(da9052_i2c_exit);
 206
 207 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
 208 MODULE_DESCRIPTION("I2C driver for Dialog DA9052 PMIC");