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/init.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[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 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 }; 136 137 static int max8925_dt_init(struct device_node *np, struct device *dev, 138 struct max8925_platform_data *pdata) 139 { 140 int ret; 141 142 ret = of_property_read_u32(np, "maxim,tsc-irq", &pdata->tsc_irq); 143 if (ret) { 144 dev_err(dev, "Not found maxim,tsc-irq property\n"); 145 return -EINVAL; 146 } 147 return 0; 148 } 149 150 static int max8925_probe(struct i2c_client *client, 151 const struct i2c_device_id *id) 152 { 153 struct max8925_platform_data *pdata = dev_get_platdata(&client->dev); 154 struct max8925_chip *chip; 155 struct device_node *node = client->dev.of_node; 156 157 if (node && !pdata) { 158 /* parse DT to get platform data */ 159 pdata = devm_kzalloc(&client->dev, 160 sizeof(struct max8925_platform_data), 161 GFP_KERNEL); 162 if (!pdata) 163 return -ENOMEM; 164 165 if (max8925_dt_init(node, &client->dev, pdata)) 166 return -EINVAL; 167 } else if (!pdata) { 168 pr_info("%s: platform data is missing\n", __func__); 169 return -EINVAL; 170 } 171 172 chip = devm_kzalloc(&client->dev, 173 sizeof(struct max8925_chip), GFP_KERNEL); 174 if (chip == NULL) 175 return -ENOMEM; 176 chip->i2c = client; 177 chip->dev = &client->dev; 178 i2c_set_clientdata(client, chip); 179 dev_set_drvdata(chip->dev, chip); 180 mutex_init(&chip->io_lock); 181 182 chip->rtc = i2c_new_dummy(chip->i2c->adapter, RTC_I2C_ADDR); 183 if (!chip->rtc) { 184 dev_err(chip->dev, "Failed to allocate I2C device for RTC\n"); 185 return -ENODEV; 186 } 187 i2c_set_clientdata(chip->rtc, chip); 188 189 chip->adc = i2c_new_dummy(chip->i2c->adapter, ADC_I2C_ADDR); 190 if (!chip->adc) { 191 dev_err(chip->dev, "Failed to allocate I2C device for ADC\n"); 192 i2c_unregister_device(chip->rtc); 193 return -ENODEV; 194 } 195 i2c_set_clientdata(chip->adc, chip); 196 197 device_init_wakeup(&client->dev, 1); 198 199 max8925_device_init(chip, pdata); 200 201 return 0; 202 } 203 204 static int max8925_remove(struct i2c_client *client) 205 { 206 struct max8925_chip *chip = i2c_get_clientdata(client); 207 208 max8925_device_exit(chip); 209 i2c_unregister_device(chip->adc); 210 i2c_unregister_device(chip->rtc); 211 return 0; 212 } 213 214 #ifdef CONFIG_PM_SLEEP 215 static int max8925_suspend(struct device *dev) 216 { 217 struct i2c_client *client = to_i2c_client(dev); 218 struct max8925_chip *chip = i2c_get_clientdata(client); 219 220 if (device_may_wakeup(dev) && chip->wakeup_flag) 221 enable_irq_wake(chip->core_irq); 222 return 0; 223 } 224 225 static int max8925_resume(struct device *dev) 226 { 227 struct i2c_client *client = to_i2c_client(dev); 228 struct max8925_chip *chip = i2c_get_clientdata(client); 229 230 if (device_may_wakeup(dev) && chip->wakeup_flag) 231 disable_irq_wake(chip->core_irq); 232 return 0; 233 } 234 #endif 235 236 static SIMPLE_DEV_PM_OPS(max8925_pm_ops, max8925_suspend, max8925_resume); 237 238 static const struct of_device_id max8925_dt_ids[] = { 239 { .compatible = "maxim,max8925", }, 240 {}, 241 }; 242 243 static struct i2c_driver max8925_driver = { 244 .driver = { 245 .name = "max8925", 246 .pm = &max8925_pm_ops, 247 .of_match_table = max8925_dt_ids, 248 }, 249 .probe = max8925_probe, 250 .remove = max8925_remove, 251 .id_table = max8925_id_table, 252 }; 253 254 static int __init max8925_i2c_init(void) 255 { 256 int ret; 257 258 ret = i2c_add_driver(&max8925_driver); 259 if (ret != 0) 260 pr_err("Failed to register MAX8925 I2C driver: %d\n", ret); 261 262 return ret; 263 } 264 subsys_initcall(max8925_i2c_init); 265