2 * atxp1.c - kernel module for setting CPU VID and general purpose
3 * I/Os using the Attansic ATXP1 chip.
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.
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.
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.
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>
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>");
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
46 static const unsigned short normal_i2c[] = { 0x37, 0x4e, I2C_CLIENT_END };
49 struct device *hwmon_dev;
50 struct mutex update_lock;
51 unsigned long last_updated;
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 */
59 u8 vrm; /* Detected CPU VRM */
62 static struct atxp1_data *atxp1_update_device(struct device *dev)
64 struct i2c_client *client;
65 struct atxp1_data *data;
67 client = to_i2c_client(dev);
68 data = i2c_get_clientdata(client);
70 mutex_lock(&data->update_lock);
72 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
74 /* Update local register data */
75 data->reg.vid = i2c_smbus_read_byte_data(client, ATXP1_VID);
76 data->reg.cpu_vid = i2c_smbus_read_byte_data(client,
78 data->reg.gpio1 = i2c_smbus_read_byte_data(client, ATXP1_GPIO1);
79 data->reg.gpio2 = i2c_smbus_read_byte_data(client, ATXP1_GPIO2);
84 mutex_unlock(&data->update_lock);
89 /* sys file functions for cpu0_vid */
90 static ssize_t atxp1_showvcore(struct device *dev,
91 struct device_attribute *attr, char *buf)
94 struct atxp1_data *data;
96 data = atxp1_update_device(dev);
98 size = sprintf(buf, "%d\n", vid_from_reg(data->reg.vid & ATXP1_VIDMASK,
104 static ssize_t atxp1_storevcore(struct device *dev,
105 struct device_attribute *attr,
106 const char *buf, size_t count)
108 struct atxp1_data *data;
109 struct i2c_client *client;
114 client = to_i2c_client(dev);
115 data = atxp1_update_device(dev);
117 err = kstrtoul(buf, 10, &vcore);
125 vid = vid_to_reg(vcore, data->vrm);
127 dev_err(dev, "VID calculation failed.\n");
132 * If output enabled, use control register value.
133 * Otherwise original CPU VID
135 if (data->reg.vid & ATXP1_VIDENA)
136 cvid = data->reg.vid & ATXP1_VIDMASK;
138 cvid = data->reg.cpu_vid;
140 /* Nothing changed, aborting */
144 dev_dbg(dev, "Setting VCore to %d mV (0x%02x)\n", (int)vcore, vid);
146 /* Write every 25 mV step to increase stability */
148 for (; cvid >= vid; cvid--)
149 i2c_smbus_write_byte_data(client,
150 ATXP1_VID, cvid | ATXP1_VIDENA);
152 for (; cvid <= vid; cvid++)
153 i2c_smbus_write_byte_data(client,
154 ATXP1_VID, cvid | ATXP1_VIDENA);
163 * CPU core reference voltage
166 static DEVICE_ATTR(cpu0_vid, S_IRUGO | S_IWUSR, atxp1_showvcore,
169 /* sys file functions for GPIO1 */
170 static ssize_t atxp1_showgpio1(struct device *dev,
171 struct device_attribute *attr, char *buf)
174 struct atxp1_data *data;
176 data = atxp1_update_device(dev);
178 size = sprintf(buf, "0x%02x\n", data->reg.gpio1 & ATXP1_GPIO1MASK);
183 static ssize_t atxp1_storegpio1(struct device *dev,
184 struct device_attribute *attr, const char *buf,
187 struct atxp1_data *data;
188 struct i2c_client *client;
192 client = to_i2c_client(dev);
193 data = atxp1_update_device(dev);
195 err = kstrtoul(buf, 16, &value);
199 value &= ATXP1_GPIO1MASK;
201 if (value != (data->reg.gpio1 & ATXP1_GPIO1MASK)) {
202 dev_info(dev, "Writing 0x%x to GPIO1.\n", (unsigned int)value);
204 i2c_smbus_write_byte_data(client, ATXP1_GPIO1, value);
213 * GPIO1 data register
214 * unit: Four bit as hex (e.g. 0x0f)
216 static DEVICE_ATTR(gpio1, S_IRUGO | S_IWUSR, atxp1_showgpio1, atxp1_storegpio1);
218 /* sys file functions for GPIO2 */
219 static ssize_t atxp1_showgpio2(struct device *dev,
220 struct device_attribute *attr, char *buf)
223 struct atxp1_data *data;
225 data = atxp1_update_device(dev);
227 size = sprintf(buf, "0x%02x\n", data->reg.gpio2);
232 static ssize_t atxp1_storegpio2(struct device *dev,
233 struct device_attribute *attr,
234 const char *buf, size_t count)
236 struct atxp1_data *data = atxp1_update_device(dev);
237 struct i2c_client *client = to_i2c_client(dev);
241 err = kstrtoul(buf, 16, &value);
246 if (value != data->reg.gpio2) {
247 dev_info(dev, "Writing 0x%x to GPIO1.\n", (unsigned int)value);
249 i2c_smbus_write_byte_data(client, ATXP1_GPIO2, value);
258 * GPIO2 data register
259 * unit: Eight bit as hex (e.g. 0xff)
261 static DEVICE_ATTR(gpio2, S_IRUGO | S_IWUSR, atxp1_showgpio2, atxp1_storegpio2);
263 static struct attribute *atxp1_attributes[] = {
264 &dev_attr_gpio1.attr,
265 &dev_attr_gpio2.attr,
266 &dev_attr_cpu0_vid.attr,
270 static const struct attribute_group atxp1_group = {
271 .attrs = atxp1_attributes,
275 /* Return 0 if detection is successful, -ENODEV otherwise */
276 static int atxp1_detect(struct i2c_client *new_client,
277 struct i2c_board_info *info)
279 struct i2c_adapter *adapter = new_client->adapter;
283 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
286 /* Detect ATXP1, checking if vendor ID registers are all zero */
287 if (!((i2c_smbus_read_byte_data(new_client, 0x3e) == 0) &&
288 (i2c_smbus_read_byte_data(new_client, 0x3f) == 0) &&
289 (i2c_smbus_read_byte_data(new_client, 0xfe) == 0) &&
290 (i2c_smbus_read_byte_data(new_client, 0xff) == 0)))
294 * No vendor ID, now checking if registers 0x10,0x11 (non-existent)
295 * showing the same as register 0x00
297 temp = i2c_smbus_read_byte_data(new_client, 0x00);
299 if (!((i2c_smbus_read_byte_data(new_client, 0x10) == temp) &&
300 (i2c_smbus_read_byte_data(new_client, 0x11) == temp)))
304 temp = vid_which_vrm();
306 if ((temp != 90) && (temp != 91)) {
307 dev_err(&adapter->dev, "atxp1: Not supporting VRM %d.%d\n",
308 temp / 10, temp % 10);
312 strlcpy(info->type, "atxp1", I2C_NAME_SIZE);
317 static int atxp1_probe(struct i2c_client *new_client,
318 const struct i2c_device_id *id)
320 struct atxp1_data *data;
323 data = devm_kzalloc(&new_client->dev, sizeof(struct atxp1_data),
329 data->vrm = vid_which_vrm();
331 i2c_set_clientdata(new_client, data);
332 mutex_init(&data->update_lock);
334 /* Register sysfs hooks */
335 err = sysfs_create_group(&new_client->dev.kobj, &atxp1_group);
339 data->hwmon_dev = hwmon_device_register(&new_client->dev);
340 if (IS_ERR(data->hwmon_dev)) {
341 err = PTR_ERR(data->hwmon_dev);
342 goto exit_remove_files;
345 dev_info(&new_client->dev, "Using VRM: %d.%d\n",
346 data->vrm / 10, data->vrm % 10);
351 sysfs_remove_group(&new_client->dev.kobj, &atxp1_group);
355 static int atxp1_remove(struct i2c_client *client)
357 struct atxp1_data *data = i2c_get_clientdata(client);
359 hwmon_device_unregister(data->hwmon_dev);
360 sysfs_remove_group(&client->dev.kobj, &atxp1_group);
365 static const struct i2c_device_id atxp1_id[] = {
369 MODULE_DEVICE_TABLE(i2c, atxp1_id);
371 static struct i2c_driver atxp1_driver = {
372 .class = I2C_CLASS_HWMON,
376 .probe = atxp1_probe,
377 .remove = atxp1_remove,
378 .id_table = atxp1_id,
379 .detect = atxp1_detect,
380 .address_list = normal_i2c,
383 module_i2c_driver(atxp1_driver);