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 21 static 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 37 static inline int max8925_write_device(struct i2c_client *i2c, 38 int reg, int bytes, void *src) 39 { 40 unsigned char buf[bytes + 1]; 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 52 int 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 } 67 EXPORT_SYMBOL(max8925_reg_read); 68 69 int 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 } 81 EXPORT_SYMBOL(max8925_reg_write); 82 83 int 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 } 95 EXPORT_SYMBOL(max8925_bulk_read); 96 97 int 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 } 109 EXPORT_SYMBOL(max8925_bulk_write); 110 111 int 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); 125 out: 126 mutex_unlock(&chip->io_lock); 127 return ret; 128 } 129 EXPORT_SYMBOL(max8925_set_bits); 130 131 132 static const struct i2c_device_id max8925_id_table[] = { 133 { "max8925", 0 }, 134 { }, 135 }; 136 MODULE_DEVICE_TABLE(i2c, max8925_id_table); 137 138 static 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 } 150 151 static 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 i2c_set_clientdata(chip->rtc, chip); 185 186 chip->adc = i2c_new_dummy(chip->i2c->adapter, ADC_I2C_ADDR); 187 i2c_set_clientdata(chip->adc, chip); 188 189 device_init_wakeup(&client->dev, 1); 190 191 max8925_device_init(chip, pdata); 192 193 return 0; 194 } 195 196 static int max8925_remove(struct i2c_client *client) 197 { 198 struct max8925_chip *chip = i2c_get_clientdata(client); 199 200 max8925_device_exit(chip); 201 i2c_unregister_device(chip->adc); 202 i2c_unregister_device(chip->rtc); 203 return 0; 204 } 205 206 #ifdef CONFIG_PM_SLEEP 207 static int max8925_suspend(struct device *dev) 208 { 209 struct i2c_client *client = container_of(dev, struct i2c_client, dev); 210 struct max8925_chip *chip = i2c_get_clientdata(client); 211 212 if (device_may_wakeup(dev) && chip->wakeup_flag) 213 enable_irq_wake(chip->core_irq); 214 return 0; 215 } 216 217 static int max8925_resume(struct device *dev) 218 { 219 struct i2c_client *client = container_of(dev, struct i2c_client, dev); 220 struct max8925_chip *chip = i2c_get_clientdata(client); 221 222 if (device_may_wakeup(dev) && chip->wakeup_flag) 223 disable_irq_wake(chip->core_irq); 224 return 0; 225 } 226 #endif 227 228 static SIMPLE_DEV_PM_OPS(max8925_pm_ops, max8925_suspend, max8925_resume); 229 230 static const struct of_device_id max8925_dt_ids[] = { 231 { .compatible = "maxim,max8925", }, 232 {}, 233 }; 234 MODULE_DEVICE_TABLE(of, max8925_dt_ids); 235 236 static struct i2c_driver max8925_driver = { 237 .driver = { 238 .name = "max8925", 239 .owner = THIS_MODULE, 240 .pm = &max8925_pm_ops, 241 .of_match_table = max8925_dt_ids, 242 }, 243 .probe = 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 ret = i2c_add_driver(&max8925_driver); 252 if (ret != 0) 253 pr_err("Failed to register MAX8925 I2C driver: %d\n", ret); 254 return ret; 255 } 256 subsys_initcall(max8925_i2c_init); 257 258 static void __exit max8925_i2c_exit(void) 259 { 260 i2c_del_driver(&max8925_driver); 261 } 262 module_exit(max8925_i2c_exit); 263 264 MODULE_DESCRIPTION("I2C Driver for Maxim 8925"); 265 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>"); 266 MODULE_LICENSE("GPL"); 267