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/i2c-sensor.h>
27 #include <linux/i2c-vid.h>
29 MODULE_LICENSE("GPL");
30 MODULE_DESCRIPTION("System voltages control via Attansic ATXP1");
31 MODULE_VERSION("0.6.2");
32 MODULE_AUTHOR("Sebastian Witt <se.witt@gmx.net>");
34 #define ATXP1_VID 0x00
35 #define ATXP1_CVID 0x01
36 #define ATXP1_GPIO1 0x06
37 #define ATXP1_GPIO2 0x0a
38 #define ATXP1_VIDENA 0x20
39 #define ATXP1_VIDMASK 0x1f
40 #define ATXP1_GPIO1MASK 0x0f
42 static unsigned short normal_i2c[] = { 0x37, 0x4e, I2C_CLIENT_END };
43 static unsigned int normal_isa[] = { I2C_CLIENT_ISA_END };
45 SENSORS_INSMOD_1(atxp1);
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);
52 static struct i2c_driver atxp1_driver = {
55 .flags = I2C_DF_NOTIFY,
56 .attach_adapter = atxp1_attach_adapter,
57 .detach_client = atxp1_detach_client,
61 struct i2c_client client;
62 struct semaphore update_lock;
63 unsigned long last_updated;
66 u8 vid; /* VID output register */
67 u8 cpu_vid; /* VID input from CPU */
68 u8 gpio1; /* General purpose I/O register 1 */
69 u8 gpio2; /* General purpose I/O register 2 */
71 u8 vrm; /* Detected CPU VRM */
74 static struct atxp1_data * atxp1_update_device(struct device *dev)
76 struct i2c_client *client;
77 struct atxp1_data *data;
79 client = to_i2c_client(dev);
80 data = i2c_get_clientdata(client);
82 down(&data->update_lock);
84 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
86 /* Update local register data */
87 data->reg.vid = i2c_smbus_read_byte_data(client, ATXP1_VID);
88 data->reg.cpu_vid = i2c_smbus_read_byte_data(client, ATXP1_CVID);
89 data->reg.gpio1 = i2c_smbus_read_byte_data(client, ATXP1_GPIO1);
90 data->reg.gpio2 = i2c_smbus_read_byte_data(client, ATXP1_GPIO2);
95 up(&data->update_lock);
100 /* sys file functions for cpu0_vid */
101 static ssize_t atxp1_showvcore(struct device *dev, struct device_attribute *attr, char *buf)
104 struct atxp1_data *data;
106 data = atxp1_update_device(dev);
108 size = sprintf(buf, "%d\n", vid_from_reg(data->reg.vid & ATXP1_VIDMASK, data->vrm));
113 static ssize_t atxp1_storevcore(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
115 struct atxp1_data *data;
116 struct i2c_client *client;
121 client = to_i2c_client(dev);
122 data = atxp1_update_device(dev);
124 vcore = simple_strtoul(buf, NULL, 10);
129 vid = vid_to_reg(vcore, data->vrm);
132 dev_err(dev, "VID calculation failed.\n");
136 /* If output enabled, use control register value. Otherwise original CPU VID */
137 if (data->reg.vid & ATXP1_VIDENA)
138 cvid = data->reg.vid & ATXP1_VIDMASK;
140 cvid = data->reg.cpu_vid;
142 /* Nothing changed, aborting */
146 dev_dbg(dev, "Setting VCore to %d mV (0x%02x)\n", vcore, vid);
148 /* Write every 25 mV step to increase stability */
150 for (; cvid >= vid; cvid--) {
151 i2c_smbus_write_byte_data(client, ATXP1_VID, cvid | ATXP1_VIDENA);
155 for (; cvid <= vid; cvid++) {
156 i2c_smbus_write_byte_data(client, ATXP1_VID, cvid | ATXP1_VIDENA);
165 /* CPU core reference voltage
168 static DEVICE_ATTR(cpu0_vid, S_IRUGO | S_IWUSR, atxp1_showvcore, atxp1_storevcore);
170 /* sys file functions for GPIO1 */
171 static ssize_t atxp1_showgpio1(struct device *dev, 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, struct device_attribute *attr, const char*buf, size_t count)
185 struct atxp1_data *data;
186 struct i2c_client *client;
189 client = to_i2c_client(dev);
190 data = atxp1_update_device(dev);
192 value = simple_strtoul(buf, NULL, 16);
194 value &= ATXP1_GPIO1MASK;
196 if (value != (data->reg.gpio1 & ATXP1_GPIO1MASK)) {
197 dev_info(dev, "Writing 0x%x to GPIO1.\n", value);
199 i2c_smbus_write_byte_data(client, ATXP1_GPIO1, value);
207 /* GPIO1 data register
208 unit: Four bit as hex (e.g. 0x0f)
210 static DEVICE_ATTR(gpio1, S_IRUGO | S_IWUSR, atxp1_showgpio1, atxp1_storegpio1);
212 /* sys file functions for GPIO2 */
213 static ssize_t atxp1_showgpio2(struct device *dev, struct device_attribute *attr, char *buf)
216 struct atxp1_data *data;
218 data = atxp1_update_device(dev);
220 size = sprintf(buf, "0x%02x\n", data->reg.gpio2);
225 static ssize_t atxp1_storegpio2(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
227 struct atxp1_data *data;
228 struct i2c_client *client;
231 client = to_i2c_client(dev);
232 data = atxp1_update_device(dev);
234 value = simple_strtoul(buf, NULL, 16) & 0xff;
236 if (value != data->reg.gpio2) {
237 dev_info(dev, "Writing 0x%x to GPIO1.\n", value);
239 i2c_smbus_write_byte_data(client, ATXP1_GPIO2, value);
247 /* GPIO2 data register
248 unit: Eight bit as hex (e.g. 0xff)
250 static DEVICE_ATTR(gpio2, S_IRUGO | S_IWUSR, atxp1_showgpio2, atxp1_storegpio2);
253 static int atxp1_attach_adapter(struct i2c_adapter *adapter)
255 return i2c_detect(adapter, &addr_data, &atxp1_detect);
258 static int atxp1_detect(struct i2c_adapter *adapter, int address, int kind)
260 struct i2c_client * new_client;
261 struct atxp1_data * data;
265 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
268 if (!(data = kmalloc(sizeof(struct atxp1_data), GFP_KERNEL))) {
273 memset(data, 0, sizeof(struct atxp1_data));
274 new_client = &data->client;
275 i2c_set_clientdata(new_client, data);
277 new_client->addr = address;
278 new_client->adapter = adapter;
279 new_client->driver = &atxp1_driver;
280 new_client->flags = 0;
282 /* Detect ATXP1, checking if vendor ID registers are all zero */
283 if (!((i2c_smbus_read_byte_data(new_client, 0x3e) == 0) &&
284 (i2c_smbus_read_byte_data(new_client, 0x3f) == 0) &&
285 (i2c_smbus_read_byte_data(new_client, 0xfe) == 0) &&
286 (i2c_smbus_read_byte_data(new_client, 0xff) == 0) )) {
288 /* No vendor ID, now checking if registers 0x10,0x11 (non-existent)
289 * showing the same as register 0x00 */
290 temp = i2c_smbus_read_byte_data(new_client, 0x00);
292 if (!((i2c_smbus_read_byte_data(new_client, 0x10) == temp) &&
293 (i2c_smbus_read_byte_data(new_client, 0x11) == temp) ))
298 data->vrm = i2c_which_vrm();
300 if ((data->vrm != 90) && (data->vrm != 91)) {
301 dev_err(&new_client->dev, "Not supporting VRM %d.%d\n",
302 data->vrm / 10, data->vrm % 10);
306 strncpy(new_client->name, "atxp1", I2C_NAME_SIZE);
310 init_MUTEX(&data->update_lock);
312 err = i2c_attach_client(new_client);
316 dev_err(&new_client->dev, "Attach client error.\n");
320 device_create_file(&new_client->dev, &dev_attr_gpio1);
321 device_create_file(&new_client->dev, &dev_attr_gpio2);
322 device_create_file(&new_client->dev, &dev_attr_cpu0_vid);
324 dev_info(&new_client->dev, "Using VRM: %d.%d\n",
325 data->vrm / 10, data->vrm % 10);
335 static int atxp1_detach_client(struct i2c_client * client)
339 err = i2c_detach_client(client);
342 dev_err(&client->dev, "Failed to detach client.\n");
344 kfree(i2c_get_clientdata(client));
349 static int __init atxp1_init(void)
351 return i2c_add_driver(&atxp1_driver);
354 static void __exit atxp1_exit(void)
356 i2c_del_driver(&atxp1_driver);
359 module_init(atxp1_init);
360 module_exit(atxp1_exit);