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 18static 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 34static 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 49int 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} 64EXPORT_SYMBOL(max8925_reg_read); 65 66int 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} 78EXPORT_SYMBOL(max8925_reg_write); 79 80int 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} 92EXPORT_SYMBOL(max8925_bulk_read); 93 94int 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} 106EXPORT_SYMBOL(max8925_bulk_write); 107 108int 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); 122out: 123 mutex_unlock(&chip->io_lock); 124 return ret; 125} 126EXPORT_SYMBOL(max8925_set_bits); 127 128 129static const struct i2c_device_id max8925_id_table[] = { 130 { "max8925", 0 }, 131 { }, 132}; 133 134static 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 147static 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 mutex_init(&chip->io_lock); 176 177 chip->rtc = i2c_new_dummy_device(chip->i2c->adapter, RTC_I2C_ADDR); 178 if (IS_ERR(chip->rtc)) { 179 dev_err(chip->dev, "Failed to allocate I2C device for RTC\n"); 180 return PTR_ERR(chip->rtc); 181 } 182 i2c_set_clientdata(chip->rtc, chip); 183 184 chip->adc = i2c_new_dummy_device(chip->i2c->adapter, ADC_I2C_ADDR); 185 if (IS_ERR(chip->adc)) { 186 dev_err(chip->dev, "Failed to allocate I2C device for ADC\n"); 187 i2c_unregister_device(chip->rtc); 188 return PTR_ERR(chip->adc); 189 } 190 i2c_set_clientdata(chip->adc, chip); 191 192 device_init_wakeup(&client->dev, 1); 193 194 max8925_device_init(chip, pdata); 195 196 return 0; 197} 198 199static void max8925_remove(struct i2c_client *client) 200{ 201 struct max8925_chip *chip = i2c_get_clientdata(client); 202 203 max8925_device_exit(chip); 204 i2c_unregister_device(chip->adc); 205 i2c_unregister_device(chip->rtc); 206} 207 208static int max8925_suspend(struct device *dev) 209{ 210 struct i2c_client *client = to_i2c_client(dev); 211 struct max8925_chip *chip = i2c_get_clientdata(client); 212 213 if (device_may_wakeup(dev) && chip->wakeup_flag) 214 enable_irq_wake(chip->core_irq); 215 return 0; 216} 217 218static int max8925_resume(struct device *dev) 219{ 220 struct i2c_client *client = to_i2c_client(dev); 221 struct max8925_chip *chip = i2c_get_clientdata(client); 222 223 if (device_may_wakeup(dev) && chip->wakeup_flag) 224 disable_irq_wake(chip->core_irq); 225 return 0; 226} 227 228static DEFINE_SIMPLE_DEV_PM_OPS(max8925_pm_ops, 229 max8925_suspend, max8925_resume); 230 231static const struct of_device_id max8925_dt_ids[] = { 232 { .compatible = "maxim,max8925", }, 233 {}, 234}; 235 236static struct i2c_driver max8925_driver = { 237 .driver = { 238 .name = "max8925", 239 .pm = pm_sleep_ptr(&max8925_pm_ops), 240 .of_match_table = max8925_dt_ids, 241 }, 242 .probe = max8925_probe, 243 .remove = max8925_remove, 244 .id_table = max8925_id_table, 245}; 246 247static int __init max8925_i2c_init(void) 248{ 249 int ret; 250 251 ret = i2c_add_driver(&max8925_driver); 252 if (ret != 0) 253 pr_err("Failed to register MAX8925 I2C driver: %d\n", ret); 254 255 return ret; 256} 257subsys_initcall(max8925_i2c_init); 258