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 default: 79 /* 80 * For other chips parking of I2C register 81 * to a safe place is not required. 82 */ 83 break; 84 } 85 86 return 0; 87 } 88 89 /* 90 * According to errata item 24, multiwrite mode should be avoided 91 * in order to prevent register data corruption after power-down. 92 */ 93 static int da9052_i2c_disable_multiwrite(struct da9052 *da9052) 94 { 95 int reg_val, ret; 96 97 ret = regmap_read(da9052->regmap, DA9052_CONTROL_B_REG, ®_val); 98 if (ret < 0) 99 return ret; 100 101 if (!(reg_val & DA9052_CONTROL_B_WRITEMODE)) { 102 reg_val |= DA9052_CONTROL_B_WRITEMODE; 103 ret = regmap_write(da9052->regmap, DA9052_CONTROL_B_REG, 104 reg_val); 105 if (ret < 0) 106 return ret; 107 } 108 109 return 0; 110 } 111 112 static const struct i2c_device_id da9052_i2c_id[] = { 113 {"da9052", DA9052}, 114 {"da9053-aa", DA9053_AA}, 115 {"da9053-ba", DA9053_BA}, 116 {"da9053-bb", DA9053_BB}, 117 {} 118 }; 119 120 #ifdef CONFIG_OF 121 static const struct of_device_id dialog_dt_ids[] = { 122 { .compatible = "dlg,da9052", .data = &da9052_i2c_id[0] }, 123 { .compatible = "dlg,da9053-aa", .data = &da9052_i2c_id[1] }, 124 { .compatible = "dlg,da9053-ab", .data = &da9052_i2c_id[2] }, 125 { .compatible = "dlg,da9053-bb", .data = &da9052_i2c_id[3] }, 126 { /* sentinel */ } 127 }; 128 #endif 129 130 static int da9052_i2c_probe(struct i2c_client *client, 131 const struct i2c_device_id *id) 132 { 133 struct da9052 *da9052; 134 int ret; 135 136 da9052 = devm_kzalloc(&client->dev, sizeof(struct da9052), GFP_KERNEL); 137 if (!da9052) 138 return -ENOMEM; 139 140 if (!i2c_check_functionality(client->adapter, 141 I2C_FUNC_SMBUS_BYTE_DATA)) { 142 dev_info(&client->dev, "Error in %s:i2c_check_functionality\n", 143 __func__); 144 return -ENODEV; 145 } 146 147 da9052->dev = &client->dev; 148 da9052->chip_irq = client->irq; 149 da9052->fix_io = da9052_i2c_fix; 150 151 i2c_set_clientdata(client, da9052); 152 153 da9052->regmap = devm_regmap_init_i2c(client, &da9052_regmap_config); 154 if (IS_ERR(da9052->regmap)) { 155 ret = PTR_ERR(da9052->regmap); 156 dev_err(&client->dev, "Failed to allocate register map: %d\n", 157 ret); 158 return ret; 159 } 160 161 ret = da9052_i2c_disable_multiwrite(da9052); 162 if (ret < 0) 163 return ret; 164 165 #ifdef CONFIG_OF 166 if (!id) { 167 struct device_node *np = client->dev.of_node; 168 const struct of_device_id *deviceid; 169 170 deviceid = of_match_node(dialog_dt_ids, np); 171 id = deviceid->data; 172 } 173 #endif 174 175 if (!id) { 176 ret = -ENODEV; 177 dev_err(&client->dev, "id is null.\n"); 178 return ret; 179 } 180 181 ret = da9052_device_init(da9052, id->driver_data); 182 if (ret != 0) 183 return ret; 184 185 return 0; 186 } 187 188 static int da9052_i2c_remove(struct i2c_client *client) 189 { 190 struct da9052 *da9052 = i2c_get_clientdata(client); 191 192 da9052_device_exit(da9052); 193 return 0; 194 } 195 196 static struct i2c_driver da9052_i2c_driver = { 197 .probe = da9052_i2c_probe, 198 .remove = da9052_i2c_remove, 199 .id_table = da9052_i2c_id, 200 .driver = { 201 .name = "da9052", 202 .owner = THIS_MODULE, 203 #ifdef CONFIG_OF 204 .of_match_table = dialog_dt_ids, 205 #endif 206 }, 207 }; 208 209 static int __init da9052_i2c_init(void) 210 { 211 int ret; 212 213 ret = i2c_add_driver(&da9052_i2c_driver); 214 if (ret != 0) { 215 pr_err("DA9052 I2C registration failed %d\n", ret); 216 return ret; 217 } 218 219 return 0; 220 } 221 subsys_initcall(da9052_i2c_init); 222 223 static void __exit da9052_i2c_exit(void) 224 { 225 i2c_del_driver(&da9052_i2c_driver); 226 } 227 module_exit(da9052_i2c_exit); 228 229 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>"); 230 MODULE_DESCRIPTION("I2C driver for Dialog DA9052 PMIC"); 231 MODULE_LICENSE("GPL"); 232