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 30 MODULE_LICENSE("GPL"); 31 MODULE_DESCRIPTION("System voltages control via Attansic ATXP1"); 32 MODULE_VERSION("0.6.2"); 33 MODULE_AUTHOR("Sebastian Witt <se.witt@gmx.net>"); 34 35 #define ATXP1_VID 0x00 36 #define ATXP1_CVID 0x01 37 #define ATXP1_GPIO1 0x06 38 #define ATXP1_GPIO2 0x0a 39 #define ATXP1_VIDENA 0x20 40 #define ATXP1_VIDMASK 0x1f 41 #define ATXP1_GPIO1MASK 0x0f 42 43 static unsigned short normal_i2c[] = { 0x37, 0x4e, I2C_CLIENT_END }; 44 45 I2C_CLIENT_INSMOD_1(atxp1); 46 47 static int atxp1_attach_adapter(struct i2c_adapter * adapter); 48 static int atxp1_detach_client(struct i2c_client * client); 49 static struct atxp1_data * atxp1_update_device(struct device *dev); 50 static int atxp1_detect(struct i2c_adapter *adapter, int address, int kind); 51 52 static struct i2c_driver atxp1_driver = { 53 .driver = { 54 .name = "atxp1", 55 }, 56 .attach_adapter = atxp1_attach_adapter, 57 .detach_client = atxp1_detach_client, 58 }; 59 60 struct atxp1_data { 61 struct i2c_client client; 62 struct class_device *class_dev; 63 struct semaphore update_lock; 64 unsigned long last_updated; 65 u8 valid; 66 struct { 67 u8 vid; /* VID output register */ 68 u8 cpu_vid; /* VID input from CPU */ 69 u8 gpio1; /* General purpose I/O register 1 */ 70 u8 gpio2; /* General purpose I/O register 2 */ 71 } reg; 72 u8 vrm; /* Detected CPU VRM */ 73 }; 74 75 static struct atxp1_data * atxp1_update_device(struct device *dev) 76 { 77 struct i2c_client *client; 78 struct atxp1_data *data; 79 80 client = to_i2c_client(dev); 81 data = i2c_get_clientdata(client); 82 83 down(&data->update_lock); 84 85 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) { 86 87 /* Update local register data */ 88 data->reg.vid = i2c_smbus_read_byte_data(client, ATXP1_VID); 89 data->reg.cpu_vid = i2c_smbus_read_byte_data(client, ATXP1_CVID); 90 data->reg.gpio1 = i2c_smbus_read_byte_data(client, ATXP1_GPIO1); 91 data->reg.gpio2 = i2c_smbus_read_byte_data(client, ATXP1_GPIO2); 92 93 data->valid = 1; 94 } 95 96 up(&data->update_lock); 97 98 return(data); 99 } 100 101 /* sys file functions for cpu0_vid */ 102 static ssize_t atxp1_showvcore(struct device *dev, struct device_attribute *attr, char *buf) 103 { 104 int size; 105 struct atxp1_data *data; 106 107 data = atxp1_update_device(dev); 108 109 size = sprintf(buf, "%d\n", vid_from_reg(data->reg.vid & ATXP1_VIDMASK, data->vrm)); 110 111 return size; 112 } 113 114 static ssize_t atxp1_storevcore(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) 115 { 116 struct atxp1_data *data; 117 struct i2c_client *client; 118 char vid; 119 char cvid; 120 unsigned int vcore; 121 122 client = to_i2c_client(dev); 123 data = atxp1_update_device(dev); 124 125 vcore = simple_strtoul(buf, NULL, 10); 126 vcore /= 25; 127 vcore *= 25; 128 129 /* Calculate VID */ 130 vid = vid_to_reg(vcore, data->vrm); 131 132 if (vid < 0) { 133 dev_err(dev, "VID calculation failed.\n"); 134 return -1; 135 } 136 137 /* If output enabled, use control register value. Otherwise original CPU VID */ 138 if (data->reg.vid & ATXP1_VIDENA) 139 cvid = data->reg.vid & ATXP1_VIDMASK; 140 else 141 cvid = data->reg.cpu_vid; 142 143 /* Nothing changed, aborting */ 144 if (vid == cvid) 145 return count; 146 147 dev_dbg(dev, "Setting VCore to %d mV (0x%02x)\n", vcore, vid); 148 149 /* Write every 25 mV step to increase stability */ 150 if (cvid > vid) { 151 for (; cvid >= vid; cvid--) { 152 i2c_smbus_write_byte_data(client, ATXP1_VID, cvid | ATXP1_VIDENA); 153 } 154 } 155 else { 156 for (; cvid <= vid; cvid++) { 157 i2c_smbus_write_byte_data(client, ATXP1_VID, cvid | ATXP1_VIDENA); 158 } 159 } 160 161 data->valid = 0; 162 163 return count; 164 } 165 166 /* CPU core reference voltage 167 unit: millivolt 168 */ 169 static DEVICE_ATTR(cpu0_vid, S_IRUGO | S_IWUSR, atxp1_showvcore, atxp1_storevcore); 170 171 /* sys file functions for GPIO1 */ 172 static ssize_t atxp1_showgpio1(struct device *dev, struct device_attribute *attr, char *buf) 173 { 174 int size; 175 struct atxp1_data *data; 176 177 data = atxp1_update_device(dev); 178 179 size = sprintf(buf, "0x%02x\n", data->reg.gpio1 & ATXP1_GPIO1MASK); 180 181 return size; 182 } 183 184 static ssize_t atxp1_storegpio1(struct device *dev, struct device_attribute *attr, const char*buf, size_t count) 185 { 186 struct atxp1_data *data; 187 struct i2c_client *client; 188 unsigned int value; 189 190 client = to_i2c_client(dev); 191 data = atxp1_update_device(dev); 192 193 value = simple_strtoul(buf, NULL, 16); 194 195 value &= ATXP1_GPIO1MASK; 196 197 if (value != (data->reg.gpio1 & ATXP1_GPIO1MASK)) { 198 dev_info(dev, "Writing 0x%x to GPIO1.\n", value); 199 200 i2c_smbus_write_byte_data(client, ATXP1_GPIO1, value); 201 202 data->valid = 0; 203 } 204 205 return count; 206 } 207 208 /* GPIO1 data register 209 unit: Four bit as hex (e.g. 0x0f) 210 */ 211 static DEVICE_ATTR(gpio1, S_IRUGO | S_IWUSR, atxp1_showgpio1, atxp1_storegpio1); 212 213 /* sys file functions for GPIO2 */ 214 static ssize_t atxp1_showgpio2(struct device *dev, struct device_attribute *attr, char *buf) 215 { 216 int size; 217 struct atxp1_data *data; 218 219 data = atxp1_update_device(dev); 220 221 size = sprintf(buf, "0x%02x\n", data->reg.gpio2); 222 223 return size; 224 } 225 226 static ssize_t atxp1_storegpio2(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) 227 { 228 struct atxp1_data *data; 229 struct i2c_client *client; 230 unsigned int value; 231 232 client = to_i2c_client(dev); 233 data = atxp1_update_device(dev); 234 235 value = simple_strtoul(buf, NULL, 16) & 0xff; 236 237 if (value != data->reg.gpio2) { 238 dev_info(dev, "Writing 0x%x to GPIO1.\n", value); 239 240 i2c_smbus_write_byte_data(client, ATXP1_GPIO2, value); 241 242 data->valid = 0; 243 } 244 245 return count; 246 } 247 248 /* GPIO2 data register 249 unit: Eight bit as hex (e.g. 0xff) 250 */ 251 static DEVICE_ATTR(gpio2, S_IRUGO | S_IWUSR, atxp1_showgpio2, atxp1_storegpio2); 252 253 254 static int atxp1_attach_adapter(struct i2c_adapter *adapter) 255 { 256 if (!(adapter->class & I2C_CLASS_HWMON)) 257 return 0; 258 return i2c_probe(adapter, &addr_data, &atxp1_detect); 259 }; 260 261 static int atxp1_detect(struct i2c_adapter *adapter, int address, int kind) 262 { 263 struct i2c_client * new_client; 264 struct atxp1_data * data; 265 int err = 0; 266 u8 temp; 267 268 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 269 goto exit; 270 271 if (!(data = kzalloc(sizeof(struct atxp1_data), GFP_KERNEL))) { 272 err = -ENOMEM; 273 goto exit; 274 } 275 276 new_client = &data->client; 277 i2c_set_clientdata(new_client, data); 278 279 new_client->addr = address; 280 new_client->adapter = adapter; 281 new_client->driver = &atxp1_driver; 282 new_client->flags = 0; 283 284 /* Detect ATXP1, checking if vendor ID registers are all zero */ 285 if (!((i2c_smbus_read_byte_data(new_client, 0x3e) == 0) && 286 (i2c_smbus_read_byte_data(new_client, 0x3f) == 0) && 287 (i2c_smbus_read_byte_data(new_client, 0xfe) == 0) && 288 (i2c_smbus_read_byte_data(new_client, 0xff) == 0) )) { 289 290 /* No vendor ID, now checking if registers 0x10,0x11 (non-existent) 291 * showing the same as register 0x00 */ 292 temp = i2c_smbus_read_byte_data(new_client, 0x00); 293 294 if (!((i2c_smbus_read_byte_data(new_client, 0x10) == temp) && 295 (i2c_smbus_read_byte_data(new_client, 0x11) == temp) )) 296 goto exit_free; 297 } 298 299 /* Get VRM */ 300 data->vrm = vid_which_vrm(); 301 302 if ((data->vrm != 90) && (data->vrm != 91)) { 303 dev_err(&new_client->dev, "Not supporting VRM %d.%d\n", 304 data->vrm / 10, data->vrm % 10); 305 goto exit_free; 306 } 307 308 strncpy(new_client->name, "atxp1", I2C_NAME_SIZE); 309 310 data->valid = 0; 311 312 init_MUTEX(&data->update_lock); 313 314 err = i2c_attach_client(new_client); 315 316 if (err) 317 { 318 dev_err(&new_client->dev, "Attach client error.\n"); 319 goto exit_free; 320 } 321 322 data->class_dev = hwmon_device_register(&new_client->dev); 323 if (IS_ERR(data->class_dev)) { 324 err = PTR_ERR(data->class_dev); 325 goto exit_detach; 326 } 327 328 device_create_file(&new_client->dev, &dev_attr_gpio1); 329 device_create_file(&new_client->dev, &dev_attr_gpio2); 330 device_create_file(&new_client->dev, &dev_attr_cpu0_vid); 331 332 dev_info(&new_client->dev, "Using VRM: %d.%d\n", 333 data->vrm / 10, data->vrm % 10); 334 335 return 0; 336 337 exit_detach: 338 i2c_detach_client(new_client); 339 exit_free: 340 kfree(data); 341 exit: 342 return err; 343 }; 344 345 static int atxp1_detach_client(struct i2c_client * client) 346 { 347 struct atxp1_data * data = i2c_get_clientdata(client); 348 int err; 349 350 hwmon_device_unregister(data->class_dev); 351 352 err = i2c_detach_client(client); 353 354 if (err) 355 dev_err(&client->dev, "Failed to detach client.\n"); 356 else 357 kfree(data); 358 359 return err; 360 }; 361 362 static int __init atxp1_init(void) 363 { 364 return i2c_add_driver(&atxp1_driver); 365 }; 366 367 static void __exit atxp1_exit(void) 368 { 369 i2c_del_driver(&atxp1_driver); 370 }; 371 372 module_init(atxp1_init); 373 module_exit(atxp1_exit); 374