1/* 2 * I2C driver for Maxim MAX8925 3 * 4 * Copyright (C) 2009 Marvell International Ltd. 5 * Haojian Zhuang <haojian.zhuang@marvell.com> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 */ 11#include <linux/kernel.h> 12#include <linux/module.h> 13#include <linux/platform_device.h> 14#include <linux/i2c.h> 15#include <linux/mfd/max8925.h> 16#include <linux/slab.h> 17 18#define RTC_I2C_ADDR 0x68 19#define ADC_I2C_ADDR 0x47 20 21static inline int max8925_read_device(struct i2c_client *i2c, 22 int reg, int bytes, void *dest) 23{ 24 int ret; 25 26 if (bytes > 1) 27 ret = i2c_smbus_read_i2c_block_data(i2c, reg, bytes, dest); 28 else { 29 ret = i2c_smbus_read_byte_data(i2c, reg); 30 if (ret < 0) 31 return ret; 32 *(unsigned char *)dest = (unsigned char)ret; 33 } 34 return ret; 35} 36 37static inline int max8925_write_device(struct i2c_client *i2c, 38 int reg, int bytes, void *src) 39{ 40 unsigned char buf[9]; 41 int ret; 42 43 buf[0] = (unsigned char)reg; 44 memcpy(&buf[1], src, bytes); 45 46 ret = i2c_master_send(i2c, buf, bytes + 1); 47 if (ret < 0) 48 return ret; 49 return 0; 50} 51 52int max8925_reg_read(struct i2c_client *i2c, int reg) 53{ 54 struct max8925_chip *chip = i2c_get_clientdata(i2c); 55 unsigned char data = 0; 56 int ret; 57 58 mutex_lock(&chip->io_lock); 59 ret = max8925_read_device(i2c, reg, 1, &data); 60 mutex_unlock(&chip->io_lock); 61 62 if (ret < 0) 63 return ret; 64 else 65 return (int)data; 66} 67EXPORT_SYMBOL(max8925_reg_read); 68 69int max8925_reg_write(struct i2c_client *i2c, int reg, 70 unsigned char data) 71{ 72 struct max8925_chip *chip = i2c_get_clientdata(i2c); 73 int ret; 74 75 mutex_lock(&chip->io_lock); 76 ret = max8925_write_device(i2c, reg, 1, &data); 77 mutex_unlock(&chip->io_lock); 78 79 return ret; 80} 81EXPORT_SYMBOL(max8925_reg_write); 82 83int max8925_bulk_read(struct i2c_client *i2c, int reg, 84 int count, unsigned char *buf) 85{ 86 struct max8925_chip *chip = i2c_get_clientdata(i2c); 87 int ret; 88 89 mutex_lock(&chip->io_lock); 90 ret = max8925_read_device(i2c, reg, count, buf); 91 mutex_unlock(&chip->io_lock); 92 93 return ret; 94} 95EXPORT_SYMBOL(max8925_bulk_read); 96 97int max8925_bulk_write(struct i2c_client *i2c, int reg, 98 int count, unsigned char *buf) 99{ 100 struct max8925_chip *chip = i2c_get_clientdata(i2c); 101 int ret; 102 103 mutex_lock(&chip->io_lock); 104 ret = max8925_write_device(i2c, reg, count, buf); 105 mutex_unlock(&chip->io_lock); 106 107 return ret; 108} 109EXPORT_SYMBOL(max8925_bulk_write); 110 111int max8925_set_bits(struct i2c_client *i2c, int reg, 112 unsigned char mask, unsigned char data) 113{ 114 struct max8925_chip *chip = i2c_get_clientdata(i2c); 115 unsigned char value; 116 int ret; 117 118 mutex_lock(&chip->io_lock); 119 ret = max8925_read_device(i2c, reg, 1, &value); 120 if (ret < 0) 121 goto out; 122 value &= ~mask; 123 value |= data; 124 ret = max8925_write_device(i2c, reg, 1, &value); 125out: 126 mutex_unlock(&chip->io_lock); 127 return ret; 128} 129EXPORT_SYMBOL(max8925_set_bits); 130 131 132static const struct i2c_device_id max8925_id_table[] = { 133 { "max8925", 0 }, 134 { }, 135}; 136MODULE_DEVICE_TABLE(i2c, max8925_id_table); 137 138static int max8925_dt_init(struct device_node *np, struct device *dev, 139 struct max8925_platform_data *pdata) 140{ 141 int ret; 142 143 ret = of_property_read_u32(np, "maxim,tsc-irq", &pdata->tsc_irq); 144 if (ret) { 145 dev_err(dev, "Not found maxim,tsc-irq property\n"); 146 return -EINVAL; 147 } 148 return 0; 149} 150 151static int max8925_probe(struct i2c_client *client, 152 const struct i2c_device_id *id) 153{ 154 struct max8925_platform_data *pdata = dev_get_platdata(&client->dev); 155 static struct max8925_chip *chip; 156 struct device_node *node = client->dev.of_node; 157 158 if (node && !pdata) { 159 /* parse DT to get platform data */ 160 pdata = devm_kzalloc(&client->dev, 161 sizeof(struct max8925_platform_data), 162 GFP_KERNEL); 163 if (!pdata) 164 return -ENOMEM; 165 166 if (max8925_dt_init(node, &client->dev, pdata)) 167 return -EINVAL; 168 } else if (!pdata) { 169 pr_info("%s: platform data is missing\n", __func__); 170 return -EINVAL; 171 } 172 173 chip = devm_kzalloc(&client->dev, 174 sizeof(struct max8925_chip), GFP_KERNEL); 175 if (chip == NULL) 176 return -ENOMEM; 177 chip->i2c = client; 178 chip->dev = &client->dev; 179 i2c_set_clientdata(client, chip); 180 dev_set_drvdata(chip->dev, chip); 181 mutex_init(&chip->io_lock); 182 183 chip->rtc = i2c_new_dummy(chip->i2c->adapter, RTC_I2C_ADDR); 184 if (!chip->rtc) { 185 dev_err(chip->dev, "Failed to allocate I2C device for RTC\n"); 186 return -ENODEV; 187 } 188 i2c_set_clientdata(chip->rtc, chip); 189 190 chip->adc = i2c_new_dummy(chip->i2c->adapter, ADC_I2C_ADDR); 191 if (!chip->adc) { 192 dev_err(chip->dev, "Failed to allocate I2C device for ADC\n"); 193 i2c_unregister_device(chip->rtc); 194 return -ENODEV; 195 } 196 i2c_set_clientdata(chip->adc, chip); 197 198 device_init_wakeup(&client->dev, 1); 199 200 max8925_device_init(chip, pdata); 201 202 return 0; 203} 204 205static int max8925_remove(struct i2c_client *client) 206{ 207 struct max8925_chip *chip = i2c_get_clientdata(client); 208 209 max8925_device_exit(chip); 210 i2c_unregister_device(chip->adc); 211 i2c_unregister_device(chip->rtc); 212 return 0; 213} 214 215#ifdef CONFIG_PM_SLEEP 216static int max8925_suspend(struct device *dev) 217{ 218 struct i2c_client *client = container_of(dev, struct i2c_client, dev); 219 struct max8925_chip *chip = i2c_get_clientdata(client); 220 221 if (device_may_wakeup(dev) && chip->wakeup_flag) 222 enable_irq_wake(chip->core_irq); 223 return 0; 224} 225 226static int max8925_resume(struct device *dev) 227{ 228 struct i2c_client *client = container_of(dev, struct i2c_client, dev); 229 struct max8925_chip *chip = i2c_get_clientdata(client); 230 231 if (device_may_wakeup(dev) && chip->wakeup_flag) 232 disable_irq_wake(chip->core_irq); 233 return 0; 234} 235#endif 236 237static SIMPLE_DEV_PM_OPS(max8925_pm_ops, max8925_suspend, max8925_resume); 238 239static const struct of_device_id max8925_dt_ids[] = { 240 { .compatible = "maxim,max8925", }, 241 {}, 242}; 243MODULE_DEVICE_TABLE(of, max8925_dt_ids); 244 245static struct i2c_driver max8925_driver = { 246 .driver = { 247 .name = "max8925", 248 .owner = THIS_MODULE, 249 .pm = &max8925_pm_ops, 250 .of_match_table = max8925_dt_ids, 251 }, 252 .probe = max8925_probe, 253 .remove = max8925_remove, 254 .id_table = max8925_id_table, 255}; 256 257static int __init max8925_i2c_init(void) 258{ 259 int ret; 260 261 ret = i2c_add_driver(&max8925_driver); 262 if (ret != 0) 263 pr_err("Failed to register MAX8925 I2C driver: %d\n", ret); 264 265 return ret; 266} 267subsys_initcall(max8925_i2c_init); 268 269static void __exit max8925_i2c_exit(void) 270{ 271 i2c_del_driver(&max8925_driver); 272} 273module_exit(max8925_i2c_exit); 274 275MODULE_DESCRIPTION("I2C Driver for Maxim 8925"); 276MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>"); 277MODULE_LICENSE("GPL"); 278