| 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 | struct atxp1_data { |
| 49 | struct i2c_client *client; |
| 50 | struct mutex update_lock; |
| 51 | unsigned long last_updated; |
| 52 | u8 valid; |
| 53 | struct { |
| 54 | u8 vid; /* VID output register */ |
| 55 | u8 cpu_vid; /* VID input from CPU */ |
| 56 | u8 gpio1; /* General purpose I/O register 1 */ |
| 57 | u8 gpio2; /* General purpose I/O register 2 */ |
| 58 | } reg; |
| 59 | u8 vrm; /* Detected CPU VRM */ |
| 60 | }; |
| 61 | |
| 62 | static struct atxp1_data *atxp1_update_device(struct device *dev) |
| 63 | { |
| 64 | struct atxp1_data *data = dev_get_drvdata(dev); |
| 65 | struct i2c_client *client = data->client; |
| 66 | |
| 67 | mutex_lock(&data->update_lock); |
| 68 | |
| 69 | if (time_after(jiffies, data->last_updated + HZ) || !data->valid) { |
| 70 | |
| 71 | /* Update local register data */ |
| 72 | data->reg.vid = i2c_smbus_read_byte_data(client, ATXP1_VID); |
| 73 | data->reg.cpu_vid = i2c_smbus_read_byte_data(client, |
| 74 | ATXP1_CVID); |
| 75 | data->reg.gpio1 = i2c_smbus_read_byte_data(client, ATXP1_GPIO1); |
| 76 | data->reg.gpio2 = i2c_smbus_read_byte_data(client, ATXP1_GPIO2); |
| 77 | |
| 78 | data->valid = 1; |
| 79 | } |
| 80 | |
| 81 | mutex_unlock(&data->update_lock); |
| 82 | |
| 83 | return data; |
| 84 | } |
| 85 | |
| 86 | /* sys file functions for cpu0_vid */ |
| 87 | static ssize_t atxp1_showvcore(struct device *dev, |
| 88 | struct device_attribute *attr, char *buf) |
| 89 | { |
| 90 | int size; |
| 91 | struct atxp1_data *data; |
| 92 | |
| 93 | data = atxp1_update_device(dev); |
| 94 | |
| 95 | size = sprintf(buf, "%d\n", vid_from_reg(data->reg.vid & ATXP1_VIDMASK, |
| 96 | data->vrm)); |
| 97 | |
| 98 | return size; |
| 99 | } |
| 100 | |
| 101 | static ssize_t atxp1_storevcore(struct device *dev, |
| 102 | struct device_attribute *attr, |
| 103 | const char *buf, size_t count) |
| 104 | { |
| 105 | struct atxp1_data *data = atxp1_update_device(dev); |
| 106 | struct i2c_client *client = data->client; |
| 107 | int vid, cvid; |
| 108 | unsigned long vcore; |
| 109 | int err; |
| 110 | |
| 111 | err = kstrtoul(buf, 10, &vcore); |
| 112 | if (err) |
| 113 | return err; |
| 114 | |
| 115 | vcore /= 25; |
| 116 | vcore *= 25; |
| 117 | |
| 118 | /* Calculate VID */ |
| 119 | vid = vid_to_reg(vcore, data->vrm); |
| 120 | if (vid < 0) { |
| 121 | dev_err(dev, "VID calculation failed.\n"); |
| 122 | return vid; |
| 123 | } |
| 124 | |
| 125 | /* |
| 126 | * If output enabled, use control register value. |
| 127 | * Otherwise original CPU VID |
| 128 | */ |
| 129 | if (data->reg.vid & ATXP1_VIDENA) |
| 130 | cvid = data->reg.vid & ATXP1_VIDMASK; |
| 131 | else |
| 132 | cvid = data->reg.cpu_vid; |
| 133 | |
| 134 | /* Nothing changed, aborting */ |
| 135 | if (vid == cvid) |
| 136 | return count; |
| 137 | |
| 138 | dev_dbg(dev, "Setting VCore to %d mV (0x%02x)\n", (int)vcore, vid); |
| 139 | |
| 140 | /* Write every 25 mV step to increase stability */ |
| 141 | if (cvid > vid) { |
| 142 | for (; cvid >= vid; cvid--) |
| 143 | i2c_smbus_write_byte_data(client, |
| 144 | ATXP1_VID, cvid | ATXP1_VIDENA); |
| 145 | } else { |
| 146 | for (; cvid <= vid; cvid++) |
| 147 | i2c_smbus_write_byte_data(client, |
| 148 | ATXP1_VID, cvid | ATXP1_VIDENA); |
| 149 | } |
| 150 | |
| 151 | data->valid = 0; |
| 152 | |
| 153 | return count; |
| 154 | } |
| 155 | |
| 156 | /* |
| 157 | * CPU core reference voltage |
| 158 | * unit: millivolt |
| 159 | */ |
| 160 | static DEVICE_ATTR(cpu0_vid, S_IRUGO | S_IWUSR, atxp1_showvcore, |
| 161 | atxp1_storevcore); |
| 162 | |
| 163 | /* sys file functions for GPIO1 */ |
| 164 | static ssize_t atxp1_showgpio1(struct device *dev, |
| 165 | struct device_attribute *attr, char *buf) |
| 166 | { |
| 167 | int size; |
| 168 | struct atxp1_data *data; |
| 169 | |
| 170 | data = atxp1_update_device(dev); |
| 171 | |
| 172 | size = sprintf(buf, "0x%02x\n", data->reg.gpio1 & ATXP1_GPIO1MASK); |
| 173 | |
| 174 | return size; |
| 175 | } |
| 176 | |
| 177 | static ssize_t atxp1_storegpio1(struct device *dev, |
| 178 | struct device_attribute *attr, const char *buf, |
| 179 | size_t count) |
| 180 | { |
| 181 | struct atxp1_data *data = atxp1_update_device(dev); |
| 182 | struct i2c_client *client = data->client; |
| 183 | unsigned long value; |
| 184 | int err; |
| 185 | |
| 186 | err = kstrtoul(buf, 16, &value); |
| 187 | if (err) |
| 188 | return err; |
| 189 | |
| 190 | value &= ATXP1_GPIO1MASK; |
| 191 | |
| 192 | if (value != (data->reg.gpio1 & ATXP1_GPIO1MASK)) { |
| 193 | dev_info(dev, "Writing 0x%x to GPIO1.\n", (unsigned int)value); |
| 194 | |
| 195 | i2c_smbus_write_byte_data(client, ATXP1_GPIO1, value); |
| 196 | |
| 197 | data->valid = 0; |
| 198 | } |
| 199 | |
| 200 | return count; |
| 201 | } |
| 202 | |
| 203 | /* |
| 204 | * GPIO1 data register |
| 205 | * unit: Four bit as hex (e.g. 0x0f) |
| 206 | */ |
| 207 | static DEVICE_ATTR(gpio1, S_IRUGO | S_IWUSR, atxp1_showgpio1, atxp1_storegpio1); |
| 208 | |
| 209 | /* sys file functions for GPIO2 */ |
| 210 | static ssize_t atxp1_showgpio2(struct device *dev, |
| 211 | struct device_attribute *attr, char *buf) |
| 212 | { |
| 213 | int size; |
| 214 | struct atxp1_data *data; |
| 215 | |
| 216 | data = atxp1_update_device(dev); |
| 217 | |
| 218 | size = sprintf(buf, "0x%02x\n", data->reg.gpio2); |
| 219 | |
| 220 | return size; |
| 221 | } |
| 222 | |
| 223 | static ssize_t atxp1_storegpio2(struct device *dev, |
| 224 | struct device_attribute *attr, |
| 225 | const char *buf, size_t count) |
| 226 | { |
| 227 | struct atxp1_data *data = atxp1_update_device(dev); |
| 228 | struct i2c_client *client = data->client; |
| 229 | unsigned long value; |
| 230 | int err; |
| 231 | |
| 232 | err = kstrtoul(buf, 16, &value); |
| 233 | if (err) |
| 234 | return err; |
| 235 | value &= 0xff; |
| 236 | |
| 237 | if (value != data->reg.gpio2) { |
| 238 | dev_info(dev, "Writing 0x%x to GPIO1.\n", (unsigned int)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 | /* |
| 249 | * GPIO2 data register |
| 250 | * unit: Eight bit as hex (e.g. 0xff) |
| 251 | */ |
| 252 | static DEVICE_ATTR(gpio2, S_IRUGO | S_IWUSR, atxp1_showgpio2, atxp1_storegpio2); |
| 253 | |
| 254 | static struct attribute *atxp1_attrs[] = { |
| 255 | &dev_attr_gpio1.attr, |
| 256 | &dev_attr_gpio2.attr, |
| 257 | &dev_attr_cpu0_vid.attr, |
| 258 | NULL |
| 259 | }; |
| 260 | ATTRIBUTE_GROUPS(atxp1); |
| 261 | |
| 262 | /* Return 0 if detection is successful, -ENODEV otherwise */ |
| 263 | static int atxp1_detect(struct i2c_client *new_client, |
| 264 | struct i2c_board_info *info) |
| 265 | { |
| 266 | struct i2c_adapter *adapter = new_client->adapter; |
| 267 | |
| 268 | u8 temp; |
| 269 | |
| 270 | if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) |
| 271 | return -ENODEV; |
| 272 | |
| 273 | /* Detect ATXP1, checking if vendor ID registers are all zero */ |
| 274 | if (!((i2c_smbus_read_byte_data(new_client, 0x3e) == 0) && |
| 275 | (i2c_smbus_read_byte_data(new_client, 0x3f) == 0) && |
| 276 | (i2c_smbus_read_byte_data(new_client, 0xfe) == 0) && |
| 277 | (i2c_smbus_read_byte_data(new_client, 0xff) == 0))) |
| 278 | return -ENODEV; |
| 279 | |
| 280 | /* |
| 281 | * No vendor ID, now checking if registers 0x10,0x11 (non-existent) |
| 282 | * showing the same as register 0x00 |
| 283 | */ |
| 284 | temp = i2c_smbus_read_byte_data(new_client, 0x00); |
| 285 | |
| 286 | if (!((i2c_smbus_read_byte_data(new_client, 0x10) == temp) && |
| 287 | (i2c_smbus_read_byte_data(new_client, 0x11) == temp))) |
| 288 | return -ENODEV; |
| 289 | |
| 290 | /* Get VRM */ |
| 291 | temp = vid_which_vrm(); |
| 292 | |
| 293 | if ((temp != 90) && (temp != 91)) { |
| 294 | dev_err(&adapter->dev, "atxp1: Not supporting VRM %d.%d\n", |
| 295 | temp / 10, temp % 10); |
| 296 | return -ENODEV; |
| 297 | } |
| 298 | |
| 299 | strlcpy(info->type, "atxp1", I2C_NAME_SIZE); |
| 300 | |
| 301 | return 0; |
| 302 | } |
| 303 | |
| 304 | static int atxp1_probe(struct i2c_client *client, |
| 305 | const struct i2c_device_id *id) |
| 306 | { |
| 307 | struct device *dev = &client->dev; |
| 308 | struct atxp1_data *data; |
| 309 | struct device *hwmon_dev; |
| 310 | |
| 311 | data = devm_kzalloc(dev, sizeof(struct atxp1_data), GFP_KERNEL); |
| 312 | if (!data) |
| 313 | return -ENOMEM; |
| 314 | |
| 315 | /* Get VRM */ |
| 316 | data->vrm = vid_which_vrm(); |
| 317 | |
| 318 | data->client = client; |
| 319 | mutex_init(&data->update_lock); |
| 320 | |
| 321 | hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, |
| 322 | data, |
| 323 | atxp1_groups); |
| 324 | if (IS_ERR(hwmon_dev)) |
| 325 | return PTR_ERR(hwmon_dev); |
| 326 | |
| 327 | dev_info(dev, "Using VRM: %d.%d\n", data->vrm / 10, data->vrm % 10); |
| 328 | |
| 329 | return 0; |
| 330 | }; |
| 331 | |
| 332 | static const struct i2c_device_id atxp1_id[] = { |
| 333 | { "atxp1", 0 }, |
| 334 | { } |
| 335 | }; |
| 336 | MODULE_DEVICE_TABLE(i2c, atxp1_id); |
| 337 | |
| 338 | static struct i2c_driver atxp1_driver = { |
| 339 | .class = I2C_CLASS_HWMON, |
| 340 | .driver = { |
| 341 | .name = "atxp1", |
| 342 | }, |
| 343 | .probe = atxp1_probe, |
| 344 | .id_table = atxp1_id, |
| 345 | .detect = atxp1_detect, |
| 346 | .address_list = normal_i2c, |
| 347 | }; |
| 348 | |
| 349 | module_i2c_driver(atxp1_driver); |