1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * I2C driver for Maxim MAX8925 4 * 5 * Copyright (C) 2009 Marvell International Ltd. 6 * Haojian Zhuang <haojian.zhuang@marvell.com> 7 */ 8 #include <linux/kernel.h> 9 #include <linux/init.h> 10 #include <linux/platform_device.h> 11 #include <linux/i2c.h> 12 #include <linux/mfd/max8925.h> 13 #include <linux/slab.h> 14 15 #define RTC_I2C_ADDR 0x68 16 #define ADC_I2C_ADDR 0x47 17 18 static inline int max8925_read_device(struct i2c_client *i2c, 19 int reg, int bytes, void *dest) 20 { 21 int ret; 22 23 if (bytes > 1) 24 ret = i2c_smbus_read_i2c_block_data(i2c, reg, bytes, dest); 25 else { 26 ret = i2c_smbus_read_byte_data(i2c, reg); 27 if (ret < 0) 28 return ret; 29 *(unsigned char *)dest = (unsigned char)ret; 30 } 31 return ret; 32 } 33 34 static inline int max8925_write_device(struct i2c_client *i2c, 35 int reg, int bytes, void *src) 36 { 37 unsigned char buf[9]; 38 int ret; 39 40 buf[0] = (unsigned char)reg; 41 memcpy(&buf[1], src, bytes); 42 43 ret = i2c_master_send(i2c, buf, bytes + 1); 44 if (ret < 0) 45 return ret; 46 return 0; 47 } 48 49 int max8925_reg_read(struct i2c_client *i2c, int reg) 50 { 51 struct max8925_chip *chip = i2c_get_clientdata(i2c); 52 unsigned char data = 0; 53 int ret; 54 55 mutex_lock(&chip->io_lock); 56 ret = max8925_read_device(i2c, reg, 1, &data); 57 mutex_unlock(&chip->io_lock); 58 59 if (ret < 0) 60 return ret; 61 else 62 return (int)data; 63 } 64 EXPORT_SYMBOL(max8925_reg_read); 65 66 int max8925_reg_write(struct i2c_client *i2c, int reg, 67 unsigned char data) 68 { 69 struct max8925_chip *chip = i2c_get_clientdata(i2c); 70 int ret; 71 72 mutex_lock(&chip->io_lock); 73 ret = max8925_write_device(i2c, reg, 1, &data); 74 mutex_unlock(&chip->io_lock); 75 76 return ret; 77 } 78 EXPORT_SYMBOL(max8925_reg_write); 79 80 int max8925_bulk_read(struct i2c_client *i2c, int reg, 81 int count, unsigned char *buf) 82 { 83 struct max8925_chip *chip = i2c_get_clientdata(i2c); 84 int ret; 85 86 mutex_lock(&chip->io_lock); 87 ret = max8925_read_device(i2c, reg, count, buf); 88 mutex_unlock(&chip->io_lock); 89 90 return ret; 91 } 92 EXPORT_SYMBOL(max8925_bulk_read); 93 94 int max8925_bulk_write(struct i2c_client *i2c, int reg, 95 int count, unsigned char *buf) 96 { 97 struct max8925_chip *chip = i2c_get_clientdata(i2c); 98 int ret; 99 100 mutex_lock(&chip->io_lock); 101 ret = max8925_write_device(i2c, reg, count, buf); 102 mutex_unlock(&chip->io_lock); 103 104 return ret; 105 } 106 EXPORT_SYMBOL(max8925_bulk_write); 107 108 int max8925_set_bits(struct i2c_client *i2c, int reg, 109 unsigned char mask, unsigned char data) 110 { 111 struct max8925_chip *chip = i2c_get_clientdata(i2c); 112 unsigned char value; 113 int ret; 114 115 mutex_lock(&chip->io_lock); 116 ret = max8925_read_device(i2c, reg, 1, &value); 117 if (ret < 0) 118 goto out; 119 value &= ~mask; 120 value |= data; 121 ret = max8925_write_device(i2c, reg, 1, &value); 122 out: 123 mutex_unlock(&chip->io_lock); 124 return ret; 125 } 126 EXPORT_SYMBOL(max8925_set_bits); 127 128 129 static const struct i2c_device_id max8925_id_table[] = { 130 { "max8925", 0 }, 131 { }, 132 }; 133 134 static int max8925_dt_init(struct device_node *np, struct device *dev, 135 struct max8925_platform_data *pdata) 136 { 137 int ret; 138 139 ret = of_property_read_u32(np, "maxim,tsc-irq", &pdata->tsc_irq); 140 if (ret) { 141 dev_err(dev, "Not found maxim,tsc-irq property\n"); 142 return -EINVAL; 143 } 144 return 0; 145 } 146 147 static int max8925_probe(struct i2c_client *client) 148 { 149 struct max8925_platform_data *pdata = dev_get_platdata(&client->dev); 150 struct max8925_chip *chip; 151 struct device_node *node = client->dev.of_node; 152 153 if (node && !pdata) { 154 /* parse DT to get platform data */ 155 pdata = devm_kzalloc(&client->dev, 156 sizeof(struct max8925_platform_data), 157 GFP_KERNEL); 158 if (!pdata) 159 return -ENOMEM; 160 161 if (max8925_dt_init(node, &client->dev, pdata)) 162 return -EINVAL; 163 } else if (!pdata) { 164 pr_info("%s: platform data is missing\n", __func__); 165 return -EINVAL; 166 } 167 168 chip = devm_kzalloc(&client->dev, 169 sizeof(struct max8925_chip), GFP_KERNEL); 170 if (chip == NULL) 171 return -ENOMEM; 172 chip->i2c = client; 173 chip->dev = &client->dev; 174 i2c_set_clientdata(client, chip); 175 dev_set_drvdata(chip->dev, chip); 176 mutex_init(&chip->io_lock); 177 178 chip->rtc = i2c_new_dummy_device(chip->i2c->adapter, RTC_I2C_ADDR); 179 if (IS_ERR(chip->rtc)) { 180 dev_err(chip->dev, "Failed to allocate I2C device for RTC\n"); 181 return PTR_ERR(chip->rtc); 182 } 183 i2c_set_clientdata(chip->rtc, chip); 184 185 chip->adc = i2c_new_dummy_device(chip->i2c->adapter, ADC_I2C_ADDR); 186 if (IS_ERR(chip->adc)) { 187 dev_err(chip->dev, "Failed to allocate I2C device for ADC\n"); 188 i2c_unregister_device(chip->rtc); 189 return PTR_ERR(chip->adc); 190 } 191 i2c_set_clientdata(chip->adc, chip); 192 193 device_init_wakeup(&client->dev, 1); 194 195 max8925_device_init(chip, pdata); 196 197 return 0; 198 } 199 200 static void max8925_remove(struct i2c_client *client) 201 { 202 struct max8925_chip *chip = i2c_get_clientdata(client); 203 204 max8925_device_exit(chip); 205 i2c_unregister_device(chip->adc); 206 i2c_unregister_device(chip->rtc); 207 } 208 209 static int max8925_suspend(struct device *dev) 210 { 211 struct i2c_client *client = to_i2c_client(dev); 212 struct max8925_chip *chip = i2c_get_clientdata(client); 213 214 if (device_may_wakeup(dev) && chip->wakeup_flag) 215 enable_irq_wake(chip->core_irq); 216 return 0; 217 } 218 219 static int max8925_resume(struct device *dev) 220 { 221 struct i2c_client *client = to_i2c_client(dev); 222 struct max8925_chip *chip = i2c_get_clientdata(client); 223 224 if (device_may_wakeup(dev) && chip->wakeup_flag) 225 disable_irq_wake(chip->core_irq); 226 return 0; 227 } 228 229 static DEFINE_SIMPLE_DEV_PM_OPS(max8925_pm_ops, 230 max8925_suspend, max8925_resume); 231 232 static const struct of_device_id max8925_dt_ids[] = { 233 { .compatible = "maxim,max8925", }, 234 {}, 235 }; 236 237 static struct i2c_driver max8925_driver = { 238 .driver = { 239 .name = "max8925", 240 .pm = pm_sleep_ptr(&max8925_pm_ops), 241 .of_match_table = max8925_dt_ids, 242 }, 243 .probe_new = max8925_probe, 244 .remove = max8925_remove, 245 .id_table = max8925_id_table, 246 }; 247 248 static int __init max8925_i2c_init(void) 249 { 250 int ret; 251 252 ret = i2c_add_driver(&max8925_driver); 253 if (ret != 0) 254 pr_err("Failed to register MAX8925 I2C driver: %d\n", ret); 255 256 return ret; 257 } 258 subsys_initcall(max8925_i2c_init); 259