1 /* 2 * I2C access for DA9052 PMICs. 3 * 4 * Copyright(c) 2011 Dialog Semiconductor Ltd. 5 * 6 * Author: David Dajun Chen <dchen@diasemi.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 * 13 */ 14 15 #include <linux/device.h> 16 #include <linux/module.h> 17 #include <linux/input.h> 18 #include <linux/mfd/core.h> 19 #include <linux/i2c.h> 20 #include <linux/err.h> 21 22 #include <linux/mfd/da9052/da9052.h> 23 #include <linux/mfd/da9052/reg.h> 24 25 #ifdef CONFIG_OF 26 #include <linux/of.h> 27 #include <linux/of_device.h> 28 #endif 29 30 /* I2C safe register check */ 31 static inline bool i2c_safe_reg(unsigned char reg) 32 { 33 switch (reg) { 34 case DA9052_STATUS_A_REG: 35 case DA9052_STATUS_B_REG: 36 case DA9052_STATUS_C_REG: 37 case DA9052_STATUS_D_REG: 38 case DA9052_ADC_RES_L_REG: 39 case DA9052_ADC_RES_H_REG: 40 case DA9052_VDD_RES_REG: 41 case DA9052_ICHG_AV_REG: 42 case DA9052_TBAT_RES_REG: 43 case DA9052_ADCIN4_RES_REG: 44 case DA9052_ADCIN5_RES_REG: 45 case DA9052_ADCIN6_RES_REG: 46 case DA9052_TJUNC_RES_REG: 47 case DA9052_TSI_X_MSB_REG: 48 case DA9052_TSI_Y_MSB_REG: 49 case DA9052_TSI_LSB_REG: 50 case DA9052_TSI_Z_MSB_REG: 51 return true; 52 default: 53 return false; 54 } 55 } 56 57 /* 58 * There is an issue with DA9052 and DA9053_AA/BA/BB PMIC where the PMIC 59 * gets lockup up or fails to respond following a system reset. 60 * This fix is to follow any read or write with a dummy read to a safe 61 * register. 62 */ 63 static int da9052_i2c_fix(struct da9052 *da9052, unsigned char reg) 64 { 65 int val; 66 67 switch (da9052->chip_id) { 68 case DA9052: 69 case DA9053_AA: 70 case DA9053_BA: 71 case DA9053_BB: 72 /* A dummy read to a safe register address. */ 73 if (!i2c_safe_reg(reg)) 74 return regmap_read(da9052->regmap, 75 DA9052_PARK_REGISTER, 76 &val); 77 break; 78 case DA9053_BC: 79 default: 80 /* 81 * For other chips parking of I2C register 82 * to a safe place is not required. 83 */ 84 break; 85 } 86 87 return 0; 88 } 89 90 /* 91 * According to errata item 24, multiwrite mode should be avoided 92 * in order to prevent register data corruption after power-down. 93 */ 94 static int da9052_i2c_disable_multiwrite(struct da9052 *da9052) 95 { 96 int reg_val, ret; 97 98 ret = regmap_read(da9052->regmap, DA9052_CONTROL_B_REG, ®_val); 99 if (ret < 0) 100 return ret; 101 102 if (!(reg_val & DA9052_CONTROL_B_WRITEMODE)) { 103 reg_val |= DA9052_CONTROL_B_WRITEMODE; 104 ret = regmap_write(da9052->regmap, DA9052_CONTROL_B_REG, 105 reg_val); 106 if (ret < 0) 107 return ret; 108 } 109 110 return 0; 111 } 112 113 static const struct i2c_device_id da9052_i2c_id[] = { 114 {"da9052", DA9052}, 115 {"da9053-aa", DA9053_AA}, 116 {"da9053-ba", DA9053_BA}, 117 {"da9053-bb", DA9053_BB}, 118 {"da9053-bc", DA9053_BC}, 119 {} 120 }; 121 122 #ifdef CONFIG_OF 123 static const struct of_device_id dialog_dt_ids[] = { 124 { .compatible = "dlg,da9052", .data = &da9052_i2c_id[0] }, 125 { .compatible = "dlg,da9053-aa", .data = &da9052_i2c_id[1] }, 126 { .compatible = "dlg,da9053-ba", .data = &da9052_i2c_id[2] }, 127 { .compatible = "dlg,da9053-bb", .data = &da9052_i2c_id[3] }, 128 { .compatible = "dlg,da9053-bc", .data = &da9052_i2c_id[4] }, 129 { /* sentinel */ } 130 }; 131 #endif 132 133 static int da9052_i2c_probe(struct i2c_client *client, 134 const struct i2c_device_id *id) 135 { 136 struct da9052 *da9052; 137 int ret; 138 139 da9052 = devm_kzalloc(&client->dev, sizeof(struct da9052), GFP_KERNEL); 140 if (!da9052) 141 return -ENOMEM; 142 143 da9052->dev = &client->dev; 144 da9052->chip_irq = client->irq; 145 da9052->fix_io = da9052_i2c_fix; 146 147 i2c_set_clientdata(client, da9052); 148 149 da9052->regmap = devm_regmap_init_i2c(client, &da9052_regmap_config); 150 if (IS_ERR(da9052->regmap)) { 151 ret = PTR_ERR(da9052->regmap); 152 dev_err(&client->dev, "Failed to allocate register map: %d\n", 153 ret); 154 return ret; 155 } 156 157 ret = da9052_i2c_disable_multiwrite(da9052); 158 if (ret < 0) 159 return ret; 160 161 #ifdef CONFIG_OF 162 if (!id) { 163 struct device_node *np = client->dev.of_node; 164 const struct of_device_id *deviceid; 165 166 deviceid = of_match_node(dialog_dt_ids, np); 167 id = deviceid->data; 168 } 169 #endif 170 171 if (!id) { 172 ret = -ENODEV; 173 dev_err(&client->dev, "id is null.\n"); 174 return ret; 175 } 176 177 ret = da9052_device_init(da9052, id->driver_data); 178 if (ret != 0) 179 return ret; 180 181 return 0; 182 } 183 184 static int da9052_i2c_remove(struct i2c_client *client) 185 { 186 struct da9052 *da9052 = i2c_get_clientdata(client); 187 188 da9052_device_exit(da9052); 189 return 0; 190 } 191 192 static struct i2c_driver da9052_i2c_driver = { 193 .probe = da9052_i2c_probe, 194 .remove = da9052_i2c_remove, 195 .id_table = da9052_i2c_id, 196 .driver = { 197 .name = "da9052", 198 .owner = THIS_MODULE, 199 #ifdef CONFIG_OF 200 .of_match_table = dialog_dt_ids, 201 #endif 202 }, 203 }; 204 205 static int __init da9052_i2c_init(void) 206 { 207 int ret; 208 209 ret = i2c_add_driver(&da9052_i2c_driver); 210 if (ret != 0) { 211 pr_err("DA9052 I2C registration failed %d\n", ret); 212 return ret; 213 } 214 215 return 0; 216 } 217 subsys_initcall(da9052_i2c_init); 218 219 static void __exit da9052_i2c_exit(void) 220 { 221 i2c_del_driver(&da9052_i2c_driver); 222 } 223 module_exit(da9052_i2c_exit); 224 225 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>"); 226 MODULE_DESCRIPTION("I2C driver for Dialog DA9052 PMIC"); 227 MODULE_LICENSE("GPL"); 228