| 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 | #include <linux/slab.h> |
| 32 | |
| 33 | MODULE_LICENSE("GPL"); |
| 34 | MODULE_DESCRIPTION("System voltages control via Attansic ATXP1"); |
| 35 | MODULE_VERSION("0.6.3"); |
| 36 | MODULE_AUTHOR("Sebastian Witt <se.witt@gmx.net>"); |
| 37 | |
| 38 | #define ATXP1_VID 0x00 |
| 39 | #define ATXP1_CVID 0x01 |
| 40 | #define ATXP1_GPIO1 0x06 |
| 41 | #define ATXP1_GPIO2 0x0a |
| 42 | #define ATXP1_VIDENA 0x20 |
| 43 | #define ATXP1_VIDMASK 0x1f |
| 44 | #define ATXP1_GPIO1MASK 0x0f |
| 45 | |
| 46 | static const unsigned short normal_i2c[] = { 0x37, 0x4e, I2C_CLIENT_END }; |
| 47 | |
| 48 | static int atxp1_probe(struct i2c_client *client, |
| 49 | const struct i2c_device_id *id); |
| 50 | static int atxp1_remove(struct i2c_client *client); |
| 51 | static struct atxp1_data *atxp1_update_device(struct device *dev); |
| 52 | static int atxp1_detect(struct i2c_client *client, struct i2c_board_info *info); |
| 53 | |
| 54 | static const struct i2c_device_id atxp1_id[] = { |
| 55 | { "atxp1", 0 }, |
| 56 | { } |
| 57 | }; |
| 58 | MODULE_DEVICE_TABLE(i2c, atxp1_id); |
| 59 | |
| 60 | static struct i2c_driver atxp1_driver = { |
| 61 | .class = I2C_CLASS_HWMON, |
| 62 | .driver = { |
| 63 | .name = "atxp1", |
| 64 | }, |
| 65 | .probe = atxp1_probe, |
| 66 | .remove = atxp1_remove, |
| 67 | .id_table = atxp1_id, |
| 68 | .detect = atxp1_detect, |
| 69 | .address_list = normal_i2c, |
| 70 | }; |
| 71 | |
| 72 | struct atxp1_data { |
| 73 | struct device *hwmon_dev; |
| 74 | struct mutex update_lock; |
| 75 | unsigned long last_updated; |
| 76 | u8 valid; |
| 77 | struct { |
| 78 | u8 vid; /* VID output register */ |
| 79 | u8 cpu_vid; /* VID input from CPU */ |
| 80 | u8 gpio1; /* General purpose I/O register 1 */ |
| 81 | u8 gpio2; /* General purpose I/O register 2 */ |
| 82 | } reg; |
| 83 | u8 vrm; /* Detected CPU VRM */ |
| 84 | }; |
| 85 | |
| 86 | static struct atxp1_data *atxp1_update_device(struct device *dev) |
| 87 | { |
| 88 | struct i2c_client *client; |
| 89 | struct atxp1_data *data; |
| 90 | |
| 91 | client = to_i2c_client(dev); |
| 92 | data = i2c_get_clientdata(client); |
| 93 | |
| 94 | mutex_lock(&data->update_lock); |
| 95 | |
| 96 | if (time_after(jiffies, data->last_updated + HZ) || !data->valid) { |
| 97 | |
| 98 | /* Update local register data */ |
| 99 | data->reg.vid = i2c_smbus_read_byte_data(client, ATXP1_VID); |
| 100 | data->reg.cpu_vid = i2c_smbus_read_byte_data(client, |
| 101 | ATXP1_CVID); |
| 102 | data->reg.gpio1 = i2c_smbus_read_byte_data(client, ATXP1_GPIO1); |
| 103 | data->reg.gpio2 = i2c_smbus_read_byte_data(client, ATXP1_GPIO2); |
| 104 | |
| 105 | data->valid = 1; |
| 106 | } |
| 107 | |
| 108 | mutex_unlock(&data->update_lock); |
| 109 | |
| 110 | return data; |
| 111 | } |
| 112 | |
| 113 | /* sys file functions for cpu0_vid */ |
| 114 | static ssize_t atxp1_showvcore(struct device *dev, |
| 115 | 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, |
| 123 | data->vrm)); |
| 124 | |
| 125 | return size; |
| 126 | } |
| 127 | |
| 128 | static ssize_t atxp1_storevcore(struct device *dev, |
| 129 | struct device_attribute *attr, |
| 130 | const char *buf, size_t count) |
| 131 | { |
| 132 | struct atxp1_data *data; |
| 133 | struct i2c_client *client; |
| 134 | int vid, cvid; |
| 135 | unsigned long vcore; |
| 136 | int err; |
| 137 | |
| 138 | client = to_i2c_client(dev); |
| 139 | data = atxp1_update_device(dev); |
| 140 | |
| 141 | err = kstrtoul(buf, 10, &vcore); |
| 142 | if (err) |
| 143 | return err; |
| 144 | |
| 145 | vcore /= 25; |
| 146 | vcore *= 25; |
| 147 | |
| 148 | /* Calculate VID */ |
| 149 | vid = vid_to_reg(vcore, data->vrm); |
| 150 | |
| 151 | if (vid < 0) { |
| 152 | dev_err(dev, "VID calculation failed.\n"); |
| 153 | return -1; |
| 154 | } |
| 155 | |
| 156 | /* |
| 157 | * If output enabled, use control register value. |
| 158 | * Otherwise original CPU VID |
| 159 | */ |
| 160 | if (data->reg.vid & ATXP1_VIDENA) |
| 161 | cvid = data->reg.vid & ATXP1_VIDMASK; |
| 162 | else |
| 163 | cvid = data->reg.cpu_vid; |
| 164 | |
| 165 | /* Nothing changed, aborting */ |
| 166 | if (vid == cvid) |
| 167 | return count; |
| 168 | |
| 169 | dev_dbg(dev, "Setting VCore to %d mV (0x%02x)\n", (int)vcore, vid); |
| 170 | |
| 171 | /* Write every 25 mV step to increase stability */ |
| 172 | if (cvid > vid) { |
| 173 | for (; cvid >= vid; cvid--) |
| 174 | i2c_smbus_write_byte_data(client, |
| 175 | ATXP1_VID, cvid | ATXP1_VIDENA); |
| 176 | } else { |
| 177 | for (; cvid <= vid; cvid++) |
| 178 | i2c_smbus_write_byte_data(client, |
| 179 | ATXP1_VID, cvid | ATXP1_VIDENA); |
| 180 | } |
| 181 | |
| 182 | data->valid = 0; |
| 183 | |
| 184 | return count; |
| 185 | } |
| 186 | |
| 187 | /* |
| 188 | * CPU core reference voltage |
| 189 | * unit: millivolt |
| 190 | */ |
| 191 | static DEVICE_ATTR(cpu0_vid, S_IRUGO | S_IWUSR, atxp1_showvcore, |
| 192 | atxp1_storevcore); |
| 193 | |
| 194 | /* sys file functions for GPIO1 */ |
| 195 | static ssize_t atxp1_showgpio1(struct device *dev, |
| 196 | struct device_attribute *attr, char *buf) |
| 197 | { |
| 198 | int size; |
| 199 | struct atxp1_data *data; |
| 200 | |
| 201 | data = atxp1_update_device(dev); |
| 202 | |
| 203 | size = sprintf(buf, "0x%02x\n", data->reg.gpio1 & ATXP1_GPIO1MASK); |
| 204 | |
| 205 | return size; |
| 206 | } |
| 207 | |
| 208 | static ssize_t atxp1_storegpio1(struct device *dev, |
| 209 | struct device_attribute *attr, const char *buf, |
| 210 | size_t count) |
| 211 | { |
| 212 | struct atxp1_data *data; |
| 213 | struct i2c_client *client; |
| 214 | unsigned long value; |
| 215 | int err; |
| 216 | |
| 217 | client = to_i2c_client(dev); |
| 218 | data = atxp1_update_device(dev); |
| 219 | |
| 220 | err = kstrtoul(buf, 16, &value); |
| 221 | if (err) |
| 222 | return err; |
| 223 | |
| 224 | value &= ATXP1_GPIO1MASK; |
| 225 | |
| 226 | if (value != (data->reg.gpio1 & ATXP1_GPIO1MASK)) { |
| 227 | dev_info(dev, "Writing 0x%x to GPIO1.\n", (unsigned int)value); |
| 228 | |
| 229 | i2c_smbus_write_byte_data(client, ATXP1_GPIO1, value); |
| 230 | |
| 231 | data->valid = 0; |
| 232 | } |
| 233 | |
| 234 | return count; |
| 235 | } |
| 236 | |
| 237 | /* |
| 238 | * GPIO1 data register |
| 239 | * unit: Four bit as hex (e.g. 0x0f) |
| 240 | */ |
| 241 | static DEVICE_ATTR(gpio1, S_IRUGO | S_IWUSR, atxp1_showgpio1, atxp1_storegpio1); |
| 242 | |
| 243 | /* sys file functions for GPIO2 */ |
| 244 | static ssize_t atxp1_showgpio2(struct device *dev, |
| 245 | struct device_attribute *attr, char *buf) |
| 246 | { |
| 247 | int size; |
| 248 | struct atxp1_data *data; |
| 249 | |
| 250 | data = atxp1_update_device(dev); |
| 251 | |
| 252 | size = sprintf(buf, "0x%02x\n", data->reg.gpio2); |
| 253 | |
| 254 | return size; |
| 255 | } |
| 256 | |
| 257 | static ssize_t atxp1_storegpio2(struct device *dev, |
| 258 | struct device_attribute *attr, |
| 259 | const char *buf, size_t count) |
| 260 | { |
| 261 | struct atxp1_data *data = atxp1_update_device(dev); |
| 262 | struct i2c_client *client = to_i2c_client(dev); |
| 263 | unsigned long value; |
| 264 | int err; |
| 265 | |
| 266 | err = kstrtoul(buf, 16, &value); |
| 267 | if (err) |
| 268 | return err; |
| 269 | value &= 0xff; |
| 270 | |
| 271 | if (value != data->reg.gpio2) { |
| 272 | dev_info(dev, "Writing 0x%x to GPIO1.\n", (unsigned int)value); |
| 273 | |
| 274 | i2c_smbus_write_byte_data(client, ATXP1_GPIO2, value); |
| 275 | |
| 276 | data->valid = 0; |
| 277 | } |
| 278 | |
| 279 | return count; |
| 280 | } |
| 281 | |
| 282 | /* |
| 283 | * GPIO2 data register |
| 284 | * unit: Eight bit as hex (e.g. 0xff) |
| 285 | */ |
| 286 | static DEVICE_ATTR(gpio2, S_IRUGO | S_IWUSR, atxp1_showgpio2, atxp1_storegpio2); |
| 287 | |
| 288 | static struct attribute *atxp1_attributes[] = { |
| 289 | &dev_attr_gpio1.attr, |
| 290 | &dev_attr_gpio2.attr, |
| 291 | &dev_attr_cpu0_vid.attr, |
| 292 | NULL |
| 293 | }; |
| 294 | |
| 295 | static const struct attribute_group atxp1_group = { |
| 296 | .attrs = atxp1_attributes, |
| 297 | }; |
| 298 | |
| 299 | |
| 300 | /* Return 0 if detection is successful, -ENODEV otherwise */ |
| 301 | static int atxp1_detect(struct i2c_client *new_client, |
| 302 | struct i2c_board_info *info) |
| 303 | { |
| 304 | struct i2c_adapter *adapter = new_client->adapter; |
| 305 | |
| 306 | u8 temp; |
| 307 | |
| 308 | if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) |
| 309 | return -ENODEV; |
| 310 | |
| 311 | /* Detect ATXP1, checking if vendor ID registers are all zero */ |
| 312 | if (!((i2c_smbus_read_byte_data(new_client, 0x3e) == 0) && |
| 313 | (i2c_smbus_read_byte_data(new_client, 0x3f) == 0) && |
| 314 | (i2c_smbus_read_byte_data(new_client, 0xfe) == 0) && |
| 315 | (i2c_smbus_read_byte_data(new_client, 0xff) == 0))) |
| 316 | return -ENODEV; |
| 317 | |
| 318 | /* |
| 319 | * No vendor ID, now checking if registers 0x10,0x11 (non-existent) |
| 320 | * showing the same as register 0x00 |
| 321 | */ |
| 322 | temp = i2c_smbus_read_byte_data(new_client, 0x00); |
| 323 | |
| 324 | if (!((i2c_smbus_read_byte_data(new_client, 0x10) == temp) && |
| 325 | (i2c_smbus_read_byte_data(new_client, 0x11) == temp))) |
| 326 | return -ENODEV; |
| 327 | |
| 328 | /* Get VRM */ |
| 329 | temp = vid_which_vrm(); |
| 330 | |
| 331 | if ((temp != 90) && (temp != 91)) { |
| 332 | dev_err(&adapter->dev, "atxp1: Not supporting VRM %d.%d\n", |
| 333 | temp / 10, temp % 10); |
| 334 | return -ENODEV; |
| 335 | } |
| 336 | |
| 337 | strlcpy(info->type, "atxp1", I2C_NAME_SIZE); |
| 338 | |
| 339 | return 0; |
| 340 | } |
| 341 | |
| 342 | static int atxp1_probe(struct i2c_client *new_client, |
| 343 | const struct i2c_device_id *id) |
| 344 | { |
| 345 | struct atxp1_data *data; |
| 346 | int err; |
| 347 | |
| 348 | data = devm_kzalloc(&new_client->dev, sizeof(struct atxp1_data), |
| 349 | GFP_KERNEL); |
| 350 | if (!data) |
| 351 | return -ENOMEM; |
| 352 | |
| 353 | /* Get VRM */ |
| 354 | data->vrm = vid_which_vrm(); |
| 355 | |
| 356 | i2c_set_clientdata(new_client, data); |
| 357 | data->valid = 0; |
| 358 | |
| 359 | mutex_init(&data->update_lock); |
| 360 | |
| 361 | /* Register sysfs hooks */ |
| 362 | err = sysfs_create_group(&new_client->dev.kobj, &atxp1_group); |
| 363 | if (err) |
| 364 | return err; |
| 365 | |
| 366 | data->hwmon_dev = hwmon_device_register(&new_client->dev); |
| 367 | if (IS_ERR(data->hwmon_dev)) { |
| 368 | err = PTR_ERR(data->hwmon_dev); |
| 369 | goto exit_remove_files; |
| 370 | } |
| 371 | |
| 372 | dev_info(&new_client->dev, "Using VRM: %d.%d\n", |
| 373 | data->vrm / 10, data->vrm % 10); |
| 374 | |
| 375 | return 0; |
| 376 | |
| 377 | exit_remove_files: |
| 378 | sysfs_remove_group(&new_client->dev.kobj, &atxp1_group); |
| 379 | return err; |
| 380 | }; |
| 381 | |
| 382 | static int atxp1_remove(struct i2c_client *client) |
| 383 | { |
| 384 | struct atxp1_data *data = i2c_get_clientdata(client); |
| 385 | |
| 386 | hwmon_device_unregister(data->hwmon_dev); |
| 387 | sysfs_remove_group(&client->dev.kobj, &atxp1_group); |
| 388 | |
| 389 | return 0; |
| 390 | }; |
| 391 | |
| 392 | module_i2c_driver(atxp1_driver); |