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("0.6.2"); 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 I2C_CLIENT_INSMOD_1(atxp1); 48 49 static int atxp1_probe(struct i2c_client *client, 50 const struct i2c_device_id *id); 51 static int atxp1_remove(struct i2c_client *client); 52 static struct atxp1_data * atxp1_update_device(struct device *dev); 53 static int atxp1_detect(struct i2c_client *client, int kind, 54 struct i2c_board_info *info); 55 56 static const struct i2c_device_id atxp1_id[] = { 57 { "atxp1", atxp1 }, 58 { } 59 }; 60 MODULE_DEVICE_TABLE(i2c, atxp1_id); 61 62 static struct i2c_driver atxp1_driver = { 63 .class = I2C_CLASS_HWMON, 64 .driver = { 65 .name = "atxp1", 66 }, 67 .probe = atxp1_probe, 68 .remove = atxp1_remove, 69 .id_table = atxp1_id, 70 .detect = atxp1_detect, 71 .address_data = &addr_data, 72 }; 73 74 struct atxp1_data { 75 struct device *hwmon_dev; 76 struct mutex update_lock; 77 unsigned long last_updated; 78 u8 valid; 79 struct { 80 u8 vid; /* VID output register */ 81 u8 cpu_vid; /* VID input from CPU */ 82 u8 gpio1; /* General purpose I/O register 1 */ 83 u8 gpio2; /* General purpose I/O register 2 */ 84 } reg; 85 u8 vrm; /* Detected CPU VRM */ 86 }; 87 88 static struct atxp1_data * atxp1_update_device(struct device *dev) 89 { 90 struct i2c_client *client; 91 struct atxp1_data *data; 92 93 client = to_i2c_client(dev); 94 data = i2c_get_clientdata(client); 95 96 mutex_lock(&data->update_lock); 97 98 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) { 99 100 /* Update local register data */ 101 data->reg.vid = i2c_smbus_read_byte_data(client, ATXP1_VID); 102 data->reg.cpu_vid = i2c_smbus_read_byte_data(client, ATXP1_CVID); 103 data->reg.gpio1 = i2c_smbus_read_byte_data(client, ATXP1_GPIO1); 104 data->reg.gpio2 = i2c_smbus_read_byte_data(client, ATXP1_GPIO2); 105 106 data->valid = 1; 107 } 108 109 mutex_unlock(&data->update_lock); 110 111 return(data); 112 } 113 114 /* sys file functions for cpu0_vid */ 115 static ssize_t atxp1_showvcore(struct device *dev, struct device_attribute *attr, char *buf) 116 { 117 int size; 118 struct atxp1_data *data; 119 120 data = atxp1_update_device(dev); 121 122 size = sprintf(buf, "%d\n", vid_from_reg(data->reg.vid & ATXP1_VIDMASK, data->vrm)); 123 124 return size; 125 } 126 127 static ssize_t atxp1_storevcore(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) 128 { 129 struct atxp1_data *data; 130 struct i2c_client *client; 131 int vid, cvid; 132 unsigned int vcore; 133 134 client = to_i2c_client(dev); 135 data = atxp1_update_device(dev); 136 137 vcore = simple_strtoul(buf, NULL, 10); 138 vcore /= 25; 139 vcore *= 25; 140 141 /* Calculate VID */ 142 vid = vid_to_reg(vcore, data->vrm); 143 144 if (vid < 0) { 145 dev_err(dev, "VID calculation failed.\n"); 146 return -1; 147 } 148 149 /* If output enabled, use control register value. Otherwise original CPU VID */ 150 if (data->reg.vid & ATXP1_VIDENA) 151 cvid = data->reg.vid & ATXP1_VIDMASK; 152 else 153 cvid = data->reg.cpu_vid; 154 155 /* Nothing changed, aborting */ 156 if (vid == cvid) 157 return count; 158 159 dev_dbg(dev, "Setting VCore to %d mV (0x%02x)\n", vcore, vid); 160 161 /* Write every 25 mV step to increase stability */ 162 if (cvid > vid) { 163 for (; cvid >= vid; cvid--) { 164 i2c_smbus_write_byte_data(client, ATXP1_VID, cvid | ATXP1_VIDENA); 165 } 166 } 167 else { 168 for (; cvid <= vid; cvid++) { 169 i2c_smbus_write_byte_data(client, ATXP1_VID, cvid | ATXP1_VIDENA); 170 } 171 } 172 173 data->valid = 0; 174 175 return count; 176 } 177 178 /* CPU core reference voltage 179 unit: millivolt 180 */ 181 static DEVICE_ATTR(cpu0_vid, S_IRUGO | S_IWUSR, atxp1_showvcore, atxp1_storevcore); 182 183 /* sys file functions for GPIO1 */ 184 static ssize_t atxp1_showgpio1(struct device *dev, struct device_attribute *attr, char *buf) 185 { 186 int size; 187 struct atxp1_data *data; 188 189 data = atxp1_update_device(dev); 190 191 size = sprintf(buf, "0x%02x\n", data->reg.gpio1 & ATXP1_GPIO1MASK); 192 193 return size; 194 } 195 196 static ssize_t atxp1_storegpio1(struct device *dev, struct device_attribute *attr, const char*buf, size_t count) 197 { 198 struct atxp1_data *data; 199 struct i2c_client *client; 200 unsigned int value; 201 202 client = to_i2c_client(dev); 203 data = atxp1_update_device(dev); 204 205 value = simple_strtoul(buf, NULL, 16); 206 207 value &= ATXP1_GPIO1MASK; 208 209 if (value != (data->reg.gpio1 & ATXP1_GPIO1MASK)) { 210 dev_info(dev, "Writing 0x%x to GPIO1.\n", value); 211 212 i2c_smbus_write_byte_data(client, ATXP1_GPIO1, value); 213 214 data->valid = 0; 215 } 216 217 return count; 218 } 219 220 /* GPIO1 data register 221 unit: Four bit as hex (e.g. 0x0f) 222 */ 223 static DEVICE_ATTR(gpio1, S_IRUGO | S_IWUSR, atxp1_showgpio1, atxp1_storegpio1); 224 225 /* sys file functions for GPIO2 */ 226 static ssize_t atxp1_showgpio2(struct device *dev, struct device_attribute *attr, char *buf) 227 { 228 int size; 229 struct atxp1_data *data; 230 231 data = atxp1_update_device(dev); 232 233 size = sprintf(buf, "0x%02x\n", data->reg.gpio2); 234 235 return size; 236 } 237 238 static ssize_t atxp1_storegpio2(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) 239 { 240 struct atxp1_data *data; 241 struct i2c_client *client; 242 unsigned int value; 243 244 client = to_i2c_client(dev); 245 data = atxp1_update_device(dev); 246 247 value = simple_strtoul(buf, NULL, 16) & 0xff; 248 249 if (value != data->reg.gpio2) { 250 dev_info(dev, "Writing 0x%x to GPIO1.\n", value); 251 252 i2c_smbus_write_byte_data(client, ATXP1_GPIO2, value); 253 254 data->valid = 0; 255 } 256 257 return count; 258 } 259 260 /* GPIO2 data register 261 unit: Eight bit as hex (e.g. 0xff) 262 */ 263 static DEVICE_ATTR(gpio2, S_IRUGO | S_IWUSR, atxp1_showgpio2, atxp1_storegpio2); 264 265 static struct attribute *atxp1_attributes[] = { 266 &dev_attr_gpio1.attr, 267 &dev_attr_gpio2.attr, 268 &dev_attr_cpu0_vid.attr, 269 NULL 270 }; 271 272 static const struct attribute_group atxp1_group = { 273 .attrs = atxp1_attributes, 274 }; 275 276 277 /* Return 0 if detection is successful, -ENODEV otherwise */ 278 static int atxp1_detect(struct i2c_client *new_client, int kind, 279 struct i2c_board_info *info) 280 { 281 struct i2c_adapter *adapter = new_client->adapter; 282 283 u8 temp; 284 285 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 286 return -ENODEV; 287 288 /* Detect ATXP1, checking if vendor ID registers are all zero */ 289 if (!((i2c_smbus_read_byte_data(new_client, 0x3e) == 0) && 290 (i2c_smbus_read_byte_data(new_client, 0x3f) == 0) && 291 (i2c_smbus_read_byte_data(new_client, 0xfe) == 0) && 292 (i2c_smbus_read_byte_data(new_client, 0xff) == 0) )) { 293 294 /* No vendor ID, now checking if registers 0x10,0x11 (non-existent) 295 * showing the same as register 0x00 */ 296 temp = i2c_smbus_read_byte_data(new_client, 0x00); 297 298 if (!((i2c_smbus_read_byte_data(new_client, 0x10) == temp) && 299 (i2c_smbus_read_byte_data(new_client, 0x11) == temp) )) 300 return -ENODEV; 301 } 302 303 /* Get VRM */ 304 temp = vid_which_vrm(); 305 306 if ((temp != 90) && (temp != 91)) { 307 dev_err(&adapter->dev, "atxp1: Not supporting VRM %d.%d\n", 308 temp / 10, temp % 10); 309 return -ENODEV; 310 } 311 312 strlcpy(info->type, "atxp1", I2C_NAME_SIZE); 313 314 return 0; 315 } 316 317 static int atxp1_probe(struct i2c_client *new_client, 318 const struct i2c_device_id *id) 319 { 320 struct atxp1_data *data; 321 int err; 322 323 data = kzalloc(sizeof(struct atxp1_data), GFP_KERNEL); 324 if (!data) { 325 err = -ENOMEM; 326 goto exit; 327 } 328 329 /* Get VRM */ 330 data->vrm = vid_which_vrm(); 331 332 i2c_set_clientdata(new_client, data); 333 data->valid = 0; 334 335 mutex_init(&data->update_lock); 336 337 /* Register sysfs hooks */ 338 if ((err = sysfs_create_group(&new_client->dev.kobj, &atxp1_group))) 339 goto exit_free; 340 341 data->hwmon_dev = hwmon_device_register(&new_client->dev); 342 if (IS_ERR(data->hwmon_dev)) { 343 err = PTR_ERR(data->hwmon_dev); 344 goto exit_remove_files; 345 } 346 347 dev_info(&new_client->dev, "Using VRM: %d.%d\n", 348 data->vrm / 10, data->vrm % 10); 349 350 return 0; 351 352 exit_remove_files: 353 sysfs_remove_group(&new_client->dev.kobj, &atxp1_group); 354 exit_free: 355 kfree(data); 356 exit: 357 return err; 358 }; 359 360 static int atxp1_remove(struct i2c_client *client) 361 { 362 struct atxp1_data * data = i2c_get_clientdata(client); 363 364 hwmon_device_unregister(data->hwmon_dev); 365 sysfs_remove_group(&client->dev.kobj, &atxp1_group); 366 367 kfree(data); 368 369 return 0; 370 }; 371 372 static int __init atxp1_init(void) 373 { 374 return i2c_add_driver(&atxp1_driver); 375 }; 376 377 static void __exit atxp1_exit(void) 378 { 379 i2c_del_driver(&atxp1_driver); 380 }; 381 382 module_init(atxp1_init); 383 module_exit(atxp1_exit); 384