summaryrefslogtreecommitdiffstats
path: root/drivers/hwmon/atxp1.c
blob: 5cf77e67a2ed1c56a46d4c21d395212f96e6c8d1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
/*
    atxp1.c - kernel module for setting CPU VID and general purpose
                     I/Os using the Attansic ATXP1 chip.

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/i2c-vid.h>
#include <linux/hwmon.h>
#include <linux/err.h>

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("System voltages control via Attansic ATXP1");
MODULE_VERSION("0.6.2");
MODULE_AUTHOR("Sebastian Witt <se.witt@gmx.net>");

#define ATXP1_VID	0x00
#define ATXP1_CVID	0x01
#define ATXP1_GPIO1	0x06
#define ATXP1_GPIO2	0x0a
#define ATXP1_VIDENA	0x20
#define ATXP1_VIDMASK	0x1f
#define ATXP1_GPIO1MASK	0x0f

static unsigned short normal_i2c[] = { 0x37, 0x4e, I2C_CLIENT_END };

I2C_CLIENT_INSMOD_1(atxp1);

static int atxp1_attach_adapter(struct i2c_adapter * adapter);
static int atxp1_detach_client(struct i2c_client * client);
static struct atxp1_data * atxp1_update_device(struct device *dev);
static int atxp1_detect(struct i2c_adapter *adapter, int address, int kind);

static struct i2c_driver atxp1_driver = {
	.owner		= THIS_MODULE,
	.name		= "atxp1",
	.flags		= I2C_DF_NOTIFY,
	.attach_adapter = atxp1_attach_adapter,
	.detach_client	= atxp1_detach_client,
};

struct atxp1_data {
	struct i2c_client client;
	struct class_device *class_dev;
	struct semaphore update_lock;
	unsigned long last_updated;
	u8 valid;
	struct {
		u8 vid;		/* VID output register */
		u8 cpu_vid; /* VID input from CPU */
		u8 gpio1;   /* General purpose I/O register 1 */
		u8 gpio2;   /* General purpose I/O register 2 */
	} reg;
	u8 vrm;			/* Detected CPU VRM */
};

static struct atxp1_data * atxp1_update_device(struct device *dev)
{
	struct i2c_client *client;
	struct atxp1_data *data;

	client = to_i2c_client(dev);
	data = i2c_get_clientdata(client);

	down(&data->update_lock);

	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {

		/* Update local register data */
		data->reg.vid = i2c_smbus_read_byte_data(client, ATXP1_VID);
		data->reg.cpu_vid = i2c_smbus_read_byte_data(client, ATXP1_CVID);
		data->reg.gpio1 = i2c_smbus_read_byte_data(client, ATXP1_GPIO1);
		data->reg.gpio2 = i2c_smbus_read_byte_data(client, ATXP1_GPIO2);

		data->valid = 1;
	}

	up(&data->update_lock);

	return(data);
}

/* sys file functions for cpu0_vid */
static ssize_t atxp1_showvcore(struct device *dev, struct device_attribute *attr, char *buf)
{
	int size;
	struct atxp1_data *data;

	data = atxp1_update_device(dev);

	size = sprintf(buf, "%d\n", vid_from_reg(data->reg.vid & ATXP1_VIDMASK, data->vrm));

	return size;
}

static ssize_t atxp1_storevcore(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
	struct atxp1_data *data;
	struct i2c_client *client;
	char vid;
	char cvid;
	unsigned int vcore;

	client = to_i2c_client(dev);
	data = atxp1_update_device(dev);

	vcore = simple_strtoul(buf, NULL, 10);
	vcore /= 25;
	vcore *= 25;

	/* Calculate VID */
	vid = vid_to_reg(vcore, data->vrm);

	if (vid < 0) {
		dev_err(dev, "VID calculation failed.\n");
		return -1;
	}

	/* If output enabled, use control register value. Otherwise original CPU VID */
	if (data->reg.vid & ATXP1_VIDENA)
		cvid = data->reg.vid & ATXP1_VIDMASK;
	else
		cvid = data->reg.cpu_vid;

	/* Nothing changed, aborting */
	if (vid == cvid)
		return count;

	dev_dbg(dev, "Setting VCore to %d mV (0x%02x)\n", vcore, vid);

	/* Write every 25 mV step to increase stability */
	if (cvid > vid) {
		for (; cvid >= vid; cvid--) {
        		i2c_smbus_write_byte_data(client, ATXP1_VID, cvid | ATXP1_VIDENA);
		}
	}
	else {
		for (; cvid <= vid; cvid++) {
        		i2c_smbus_write_byte_data(client, ATXP1_VID, cvid | ATXP1_VIDENA);
		}
	}

	data->valid = 0;

	return count;
}

/* CPU core reference voltage
    unit: millivolt
*/
static DEVICE_ATTR(cpu0_vid, S_IRUGO | S_IWUSR, atxp1_showvcore, atxp1_storevcore);

/* sys file functions for GPIO1 */
static ssize_t atxp1_showgpio1(struct device *dev, struct device_attribute *attr, char *buf)
{
	int size;
	struct atxp1_data *data;

	data = atxp1_update_device(dev);

	size = sprintf(buf, "0x%02x\n", data->reg.gpio1 & ATXP1_GPIO1MASK);

	return size;
}

static ssize_t atxp1_storegpio1(struct device *dev, struct device_attribute *attr, const char*buf, size_t count)
{
	struct atxp1_data *data;
	struct i2c_client *client;
	unsigned int value;

	client = to_i2c_client(dev);
	data = atxp1_update_device(dev);

	value = simple_strtoul(buf, NULL, 16);

	value &= ATXP1_GPIO1MASK;

	if (value != (data->reg.gpio1 & ATXP1_GPIO1MASK)) {
		dev_info(dev, "Writing 0x%x to GPIO1.\n", value);

		i2c_smbus_write_byte_data(client, ATXP1_GPIO1, value);

		data->valid = 0;
	}

	return count;
}

/* GPIO1 data register
    unit: Four bit as hex (e.g. 0x0f)
*/
static DEVICE_ATTR(gpio1, S_IRUGO | S_IWUSR, atxp1_showgpio1, atxp1_storegpio1);

/* sys file functions for GPIO2 */
static ssize_t atxp1_showgpio2(struct device *dev, struct device_attribute *attr, char *buf)
{
	int size;
	struct atxp1_data *data;

	data = atxp1_update_device(dev);

	size = sprintf(buf, "0x%02x\n", data->reg.gpio2);

	return size;
}

static ssize_t atxp1_storegpio2(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
	struct atxp1_data *data;
	struct i2c_client *client;
	unsigned int value;

	client = to_i2c_client(dev);
	data = atxp1_update_device(dev);

	value = simple_strtoul(buf, NULL, 16) & 0xff;

	if (value != data->reg.gpio2) {
		dev_info(dev, "Writing 0x%x to GPIO1.\n", value);

		i2c_smbus_write_byte_data(client, ATXP1_GPIO2, value);

		data->valid = 0;
	}

	return count;
}

/* GPIO2 data register
    unit: Eight bit as hex (e.g. 0xff)
*/
static DEVICE_ATTR(gpio2, S_IRUGO | S_IWUSR, atxp1_showgpio2, atxp1_storegpio2);


static int atxp1_attach_adapter(struct i2c_adapter *adapter)
{
	return i2c_probe(adapter, &addr_data, &atxp1_detect);
};

static int atxp1_detect(struct i2c_adapter *adapter, int address, int kind)
{
	struct i2c_client * new_client;
	struct atxp1_data * data;
	int err = 0;
	u8 temp;

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
		goto exit;

	if (!(data = kmalloc(sizeof(struct atxp1_data), GFP_KERNEL))) {
		err = -ENOMEM;
		goto exit;
	}

	memset(data, 0, sizeof(struct atxp1_data));
	new_client = &data->client;
	i2c_set_clientdata(new_client, data);

	new_client->addr = address;
	new_client->adapter = adapter;
	new_client->driver = &atxp1_driver;
	new_client->flags = 0;

	/* Detect ATXP1, checking if vendor ID registers are all zero */
	if (!((i2c_smbus_read_byte_data(new_client, 0x3e) == 0) &&
	     (i2c_smbus_read_byte_data(new_client, 0x3f) == 0) &&
	     (i2c_smbus_read_byte_data(new_client, 0xfe) == 0) &&
	     (i2c_smbus_read_byte_data(new_client, 0xff) == 0) )) {

		/* No vendor ID, now checking if registers 0x10,0x11 (non-existent)
		 * showing the same as register 0x00 */
		temp = i2c_smbus_read_byte_data(new_client, 0x00);

		if (!((i2c_smbus_read_byte_data(new_client, 0x10) == temp) &&
			 (i2c_smbus_read_byte_data(new_client, 0x11) == temp) ))
			goto exit_free;
	}

	/* Get VRM */
	data->vrm = i2c_which_vrm();

	if ((data->vrm != 90) && (data->vrm != 91)) {
		dev_err(&new_client->dev, "Not supporting VRM %d.%d\n",
				data->vrm / 10, data->vrm % 10);
		goto exit_free;
	}

	strncpy(new_client->name, "atxp1", I2C_NAME_SIZE);

	data->valid = 0;

	init_MUTEX(&data->update_lock);

	err = i2c_attach_client(new_client);

	if (err)
	{
		dev_err(&new_client->dev, "Attach client error.\n");
		goto exit_free;
	}

	data->class_dev = hwmon_device_register(&new_client->dev);
	if (IS_ERR(data->class_dev)) {
		err = PTR_ERR(data->class_dev);
		goto exit_detach;
	}

	device_create_file(&new_client->dev, &dev_attr_gpio1);
	device_create_file(&new_client->dev, &dev_attr_gpio2);
	device_create_file(&new_client->dev, &dev_attr_cpu0_vid);

	dev_info(&new_client->dev, "Using VRM: %d.%d\n",
			 data->vrm / 10, data->vrm % 10);

	return 0;

exit_detach:
	i2c_detach_client(new_client);
exit_free:
	kfree(data);
exit:
	return err;
};

static int atxp1_detach_client(struct i2c_client * client)
{
	struct atxp1_data * data = i2c_get_clientdata(client);
	int err;

	hwmon_device_unregister(data->class_dev);

	err = i2c_detach_client(client);

	if (err)
		dev_err(&client->dev, "Failed to detach client.\n");
	else
		kfree(data);

	return err;
};

static int __init atxp1_init(void)
{
	return i2c_add_driver(&atxp1_driver);
};

static void __exit atxp1_exit(void)
{
	i2c_del_driver(&atxp1_driver);
};

module_init(atxp1_init);
module_exit(atxp1_exit);