1 /* 2 atxp1.c - kernel module for setting CPU VID and general purpose 3 I/Os using the Attansic ATXP1 chip. 4 5 This program is free software; you can redistribute it and/or modify 6 it under the terms of the GNU General Public License as published by 7 the Free Software Foundation; either version 2 of the License, or 8 (at your option) any later version. 9 10 This program is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 GNU General Public License for more details. 14 15 You should have received a copy of the GNU General Public License 16 along with this program; if not, write to the Free Software 17 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 18 19 */ 20 21 #include <linux/kernel.h> 22 #include <linux/init.h> 23 #include <linux/module.h> 24 #include <linux/jiffies.h> 25 #include <linux/i2c.h> 26 #include <linux/hwmon.h> 27 #include <linux/hwmon-vid.h> 28 #include <linux/err.h> 29 #include <linux/mutex.h> 30 #include <linux/sysfs.h> 31 32 MODULE_LICENSE("GPL"); 33 MODULE_DESCRIPTION("System voltages control via Attansic ATXP1"); 34 MODULE_VERSION("0.6.3"); 35 MODULE_AUTHOR("Sebastian Witt <se.witt@gmx.net>"); 36 37 #define ATXP1_VID 0x00 38 #define ATXP1_CVID 0x01 39 #define ATXP1_GPIO1 0x06 40 #define ATXP1_GPIO2 0x0a 41 #define ATXP1_VIDENA 0x20 42 #define ATXP1_VIDMASK 0x1f 43 #define ATXP1_GPIO1MASK 0x0f 44 45 static const unsigned short normal_i2c[] = { 0x37, 0x4e, I2C_CLIENT_END }; 46 47 static int atxp1_probe(struct i2c_client *client, 48 const struct i2c_device_id *id); 49 static int atxp1_remove(struct i2c_client *client); 50 static struct atxp1_data * atxp1_update_device(struct device *dev); 51 static int atxp1_detect(struct i2c_client *client, struct i2c_board_info *info); 52 53 static const struct i2c_device_id atxp1_id[] = { 54 { "atxp1", 0 }, 55 { } 56 }; 57 MODULE_DEVICE_TABLE(i2c, atxp1_id); 58 59 static struct i2c_driver atxp1_driver = { 60 .class = I2C_CLASS_HWMON, 61 .driver = { 62 .name = "atxp1", 63 }, 64 .probe = atxp1_probe, 65 .remove = atxp1_remove, 66 .id_table = atxp1_id, 67 .detect = atxp1_detect, 68 .address_list = normal_i2c, 69 }; 70 71 struct atxp1_data { 72 struct device *hwmon_dev; 73 struct mutex update_lock; 74 unsigned long last_updated; 75 u8 valid; 76 struct { 77 u8 vid; /* VID output register */ 78 u8 cpu_vid; /* VID input from CPU */ 79 u8 gpio1; /* General purpose I/O register 1 */ 80 u8 gpio2; /* General purpose I/O register 2 */ 81 } reg; 82 u8 vrm; /* Detected CPU VRM */ 83 }; 84 85 static struct atxp1_data * atxp1_update_device(struct device *dev) 86 { 87 struct i2c_client *client; 88 struct atxp1_data *data; 89 90 client = to_i2c_client(dev); 91 data = i2c_get_clientdata(client); 92 93 mutex_lock(&data->update_lock); 94 95 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) { 96 97 /* Update local register data */ 98 data->reg.vid = i2c_smbus_read_byte_data(client, ATXP1_VID); 99 data->reg.cpu_vid = i2c_smbus_read_byte_data(client, ATXP1_CVID); 100 data->reg.gpio1 = i2c_smbus_read_byte_data(client, ATXP1_GPIO1); 101 data->reg.gpio2 = i2c_smbus_read_byte_data(client, ATXP1_GPIO2); 102 103 data->valid = 1; 104 } 105 106 mutex_unlock(&data->update_lock); 107 108 return(data); 109 } 110 111 /* sys file functions for cpu0_vid */ 112 static ssize_t atxp1_showvcore(struct device *dev, struct device_attribute *attr, char *buf) 113 { 114 int size; 115 struct atxp1_data *data; 116 117 data = atxp1_update_device(dev); 118 119 size = sprintf(buf, "%d\n", vid_from_reg(data->reg.vid & ATXP1_VIDMASK, data->vrm)); 120 121 return size; 122 } 123 124 static ssize_t atxp1_storevcore(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) 125 { 126 struct atxp1_data *data; 127 struct i2c_client *client; 128 int vid, cvid; 129 unsigned int vcore; 130 131 client = to_i2c_client(dev); 132 data = atxp1_update_device(dev); 133 134 vcore = simple_strtoul(buf, NULL, 10); 135 vcore /= 25; 136 vcore *= 25; 137 138 /* Calculate VID */ 139 vid = vid_to_reg(vcore, data->vrm); 140 141 if (vid < 0) { 142 dev_err(dev, "VID calculation failed.\n"); 143 return -1; 144 } 145 146 /* If output enabled, use control register value. Otherwise original CPU VID */ 147 if (data->reg.vid & ATXP1_VIDENA) 148 cvid = data->reg.vid & ATXP1_VIDMASK; 149 else 150 cvid = data->reg.cpu_vid; 151 152 /* Nothing changed, aborting */ 153 if (vid == cvid) 154 return count; 155 156 dev_dbg(dev, "Setting VCore to %d mV (0x%02x)\n", vcore, vid); 157 158 /* Write every 25 mV step to increase stability */ 159 if (cvid > vid) { 160 for (; cvid >= vid; cvid--) { 161 i2c_smbus_write_byte_data(client, ATXP1_VID, cvid | ATXP1_VIDENA); 162 } 163 } 164 else { 165 for (; cvid <= vid; cvid++) { 166 i2c_smbus_write_byte_data(client, ATXP1_VID, cvid | ATXP1_VIDENA); 167 } 168 } 169 170 data->valid = 0; 171 172 return count; 173 } 174 175 /* CPU core reference voltage 176 unit: millivolt 177 */ 178 static DEVICE_ATTR(cpu0_vid, S_IRUGO | S_IWUSR, atxp1_showvcore, atxp1_storevcore); 179 180 /* sys file functions for GPIO1 */ 181 static ssize_t atxp1_showgpio1(struct device *dev, struct device_attribute *attr, char *buf) 182 { 183 int size; 184 struct atxp1_data *data; 185 186 data = atxp1_update_device(dev); 187 188 size = sprintf(buf, "0x%02x\n", data->reg.gpio1 & ATXP1_GPIO1MASK); 189 190 return size; 191 } 192 193 static ssize_t atxp1_storegpio1(struct device *dev, struct device_attribute *attr, const char*buf, size_t count) 194 { 195 struct atxp1_data *data; 196 struct i2c_client *client; 197 unsigned int value; 198 199 client = to_i2c_client(dev); 200 data = atxp1_update_device(dev); 201 202 value = simple_strtoul(buf, NULL, 16); 203 204 value &= ATXP1_GPIO1MASK; 205 206 if (value != (data->reg.gpio1 & ATXP1_GPIO1MASK)) { 207 dev_info(dev, "Writing 0x%x to GPIO1.\n", value); 208 209 i2c_smbus_write_byte_data(client, ATXP1_GPIO1, value); 210 211 data->valid = 0; 212 } 213 214 return count; 215 } 216 217 /* GPIO1 data register 218 unit: Four bit as hex (e.g. 0x0f) 219 */ 220 static DEVICE_ATTR(gpio1, S_IRUGO | S_IWUSR, atxp1_showgpio1, atxp1_storegpio1); 221 222 /* sys file functions for GPIO2 */ 223 static ssize_t atxp1_showgpio2(struct device *dev, struct device_attribute *attr, char *buf) 224 { 225 int size; 226 struct atxp1_data *data; 227 228 data = atxp1_update_device(dev); 229 230 size = sprintf(buf, "0x%02x\n", data->reg.gpio2); 231 232 return size; 233 } 234 235 static ssize_t atxp1_storegpio2(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) 236 { 237 struct atxp1_data *data; 238 struct i2c_client *client; 239 unsigned int value; 240 241 client = to_i2c_client(dev); 242 data = atxp1_update_device(dev); 243 244 value = simple_strtoul(buf, NULL, 16) & 0xff; 245 246 if (value != data->reg.gpio2) { 247 dev_info(dev, "Writing 0x%x to GPIO1.\n", value); 248 249 i2c_smbus_write_byte_data(client, ATXP1_GPIO2, value); 250 251 data->valid = 0; 252 } 253 254 return count; 255 } 256 257 /* GPIO2 data register 258 unit: Eight bit as hex (e.g. 0xff) 259 */ 260 static DEVICE_ATTR(gpio2, S_IRUGO | S_IWUSR, atxp1_showgpio2, atxp1_storegpio2); 261 262 static struct attribute *atxp1_attributes[] = { 263 &dev_attr_gpio1.attr, 264 &dev_attr_gpio2.attr, 265 &dev_attr_cpu0_vid.attr, 266 NULL 267 }; 268 269 static const struct attribute_group atxp1_group = { 270 .attrs = atxp1_attributes, 271 }; 272 273 274 /* Return 0 if detection is successful, -ENODEV otherwise */ 275 static int atxp1_detect(struct i2c_client *new_client, 276 struct i2c_board_info *info) 277 { 278 struct i2c_adapter *adapter = new_client->adapter; 279 280 u8 temp; 281 282 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 283 return -ENODEV; 284 285 /* Detect ATXP1, checking if vendor ID registers are all zero */ 286 if (!((i2c_smbus_read_byte_data(new_client, 0x3e) == 0) && 287 (i2c_smbus_read_byte_data(new_client, 0x3f) == 0) && 288 (i2c_smbus_read_byte_data(new_client, 0xfe) == 0) && 289 (i2c_smbus_read_byte_data(new_client, 0xff) == 0))) 290 return -ENODEV; 291 292 /* No vendor ID, now checking if registers 0x10,0x11 (non-existent) 293 * showing the same as register 0x00 */ 294 temp = i2c_smbus_read_byte_data(new_client, 0x00); 295 296 if (!((i2c_smbus_read_byte_data(new_client, 0x10) == temp) && 297 (i2c_smbus_read_byte_data(new_client, 0x11) == temp))) 298 return -ENODEV; 299 300 /* Get VRM */ 301 temp = vid_which_vrm(); 302 303 if ((temp != 90) && (temp != 91)) { 304 dev_err(&adapter->dev, "atxp1: Not supporting VRM %d.%d\n", 305 temp / 10, temp % 10); 306 return -ENODEV; 307 } 308 309 strlcpy(info->type, "atxp1", I2C_NAME_SIZE); 310 311 return 0; 312 } 313 314 static int atxp1_probe(struct i2c_client *new_client, 315 const struct i2c_device_id *id) 316 { 317 struct atxp1_data *data; 318 int err; 319 320 data = kzalloc(sizeof(struct atxp1_data), GFP_KERNEL); 321 if (!data) { 322 err = -ENOMEM; 323 goto exit; 324 } 325 326 /* Get VRM */ 327 data->vrm = vid_which_vrm(); 328 329 i2c_set_clientdata(new_client, data); 330 data->valid = 0; 331 332 mutex_init(&data->update_lock); 333 334 /* Register sysfs hooks */ 335 if ((err = sysfs_create_group(&new_client->dev.kobj, &atxp1_group))) 336 goto exit_free; 337 338 data->hwmon_dev = hwmon_device_register(&new_client->dev); 339 if (IS_ERR(data->hwmon_dev)) { 340 err = PTR_ERR(data->hwmon_dev); 341 goto exit_remove_files; 342 } 343 344 dev_info(&new_client->dev, "Using VRM: %d.%d\n", 345 data->vrm / 10, data->vrm % 10); 346 347 return 0; 348 349 exit_remove_files: 350 sysfs_remove_group(&new_client->dev.kobj, &atxp1_group); 351 exit_free: 352 kfree(data); 353 exit: 354 return err; 355 }; 356 357 static int atxp1_remove(struct i2c_client *client) 358 { 359 struct atxp1_data * data = i2c_get_clientdata(client); 360 361 hwmon_device_unregister(data->hwmon_dev); 362 sysfs_remove_group(&client->dev.kobj, &atxp1_group); 363 364 kfree(data); 365 366 return 0; 367 }; 368 369 static int __init atxp1_init(void) 370 { 371 return i2c_add_driver(&atxp1_driver); 372 }; 373 374 static void __exit atxp1_exit(void) 375 { 376 i2c_del_driver(&atxp1_driver); 377 }; 378 379 module_init(atxp1_init); 380 module_exit(atxp1_exit); 381