xref: /linux/drivers/hwmon/smsc47b397.c (revision c537b994505099b7197e7d3125b942ecbcc51eb6)
1 /*
2     smsc47b397.c - Part of lm_sensors, Linux kernel modules
3 			for hardware monitoring
4 
5     Supports the SMSC LPC47B397-NC Super-I/O chip.
6 
7     Author/Maintainer: Mark M. Hoffman <mhoffman@lightlink.com>
8 	Copyright (C) 2004 Utilitek Systems, Inc.
9 
10     derived in part from smsc47m1.c:
11 	Copyright (C) 2002 Mark D. Studebaker <mdsxyz123@yahoo.com>
12 	Copyright (C) 2004 Jean Delvare <khali@linux-fr.org>
13 
14     This program is free software; you can redistribute it and/or modify
15     it under the terms of the GNU General Public License as published by
16     the Free Software Foundation; either version 2 of the License, or
17     (at your option) any later version.
18 
19     This program is distributed in the hope that it will be useful,
20     but WITHOUT ANY WARRANTY; without even the implied warranty of
21     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22     GNU General Public License for more details.
23 
24     You should have received a copy of the GNU General Public License
25     along with this program; if not, write to the Free Software
26     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
27 */
28 
29 #include <linux/module.h>
30 #include <linux/slab.h>
31 #include <linux/ioport.h>
32 #include <linux/jiffies.h>
33 #include <linux/i2c.h>
34 #include <linux/i2c-isa.h>
35 #include <linux/hwmon.h>
36 #include <linux/err.h>
37 #include <linux/init.h>
38 #include <linux/mutex.h>
39 #include <asm/io.h>
40 
41 /* Address is autodetected, there is no default value */
42 static unsigned short address;
43 
44 /* Super-I/0 registers and commands */
45 
46 #define	REG	0x2e	/* The register to read/write */
47 #define	VAL	0x2f	/* The value to read/write */
48 
49 static inline void superio_outb(int reg, int val)
50 {
51 	outb(reg, REG);
52 	outb(val, VAL);
53 }
54 
55 static inline int superio_inb(int reg)
56 {
57 	outb(reg, REG);
58 	return inb(VAL);
59 }
60 
61 /* select superio logical device */
62 static inline void superio_select(int ld)
63 {
64 	superio_outb(0x07, ld);
65 }
66 
67 static inline void superio_enter(void)
68 {
69 	outb(0x55, REG);
70 }
71 
72 static inline void superio_exit(void)
73 {
74 	outb(0xAA, REG);
75 }
76 
77 #define SUPERIO_REG_DEVID	0x20
78 #define SUPERIO_REG_DEVREV	0x21
79 #define SUPERIO_REG_BASE_MSB	0x60
80 #define SUPERIO_REG_BASE_LSB	0x61
81 #define SUPERIO_REG_LD8		0x08
82 
83 #define SMSC_EXTENT		0x02
84 
85 /* 0 <= nr <= 3 */
86 static u8 smsc47b397_reg_temp[] = {0x25, 0x26, 0x27, 0x80};
87 #define SMSC47B397_REG_TEMP(nr)	(smsc47b397_reg_temp[(nr)])
88 
89 /* 0 <= nr <= 3 */
90 #define SMSC47B397_REG_FAN_LSB(nr) (0x28 + 2 * (nr))
91 #define SMSC47B397_REG_FAN_MSB(nr) (0x29 + 2 * (nr))
92 
93 struct smsc47b397_data {
94 	struct i2c_client client;
95 	struct class_device *class_dev;
96 	struct mutex lock;
97 
98 	struct mutex update_lock;
99 	unsigned long last_updated; /* in jiffies */
100 	int valid;
101 
102 	/* register values */
103 	u16 fan[4];
104 	u8 temp[4];
105 };
106 
107 static int smsc47b397_read_value(struct i2c_client *client, u8 reg)
108 {
109 	struct smsc47b397_data *data = i2c_get_clientdata(client);
110 	int res;
111 
112 	mutex_lock(&data->lock);
113 	outb(reg, client->addr);
114 	res = inb_p(client->addr + 1);
115 	mutex_unlock(&data->lock);
116 	return res;
117 }
118 
119 static struct smsc47b397_data *smsc47b397_update_device(struct device *dev)
120 {
121  	struct i2c_client *client = to_i2c_client(dev);
122 	struct smsc47b397_data *data = i2c_get_clientdata(client);
123 	int i;
124 
125 	mutex_lock(&data->update_lock);
126 
127 	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
128 		dev_dbg(&client->dev, "starting device update...\n");
129 
130 		/* 4 temperature inputs, 4 fan inputs */
131 		for (i = 0; i < 4; i++) {
132 			data->temp[i] = smsc47b397_read_value(client,
133 					SMSC47B397_REG_TEMP(i));
134 
135 			/* must read LSB first */
136 			data->fan[i]  = smsc47b397_read_value(client,
137 					SMSC47B397_REG_FAN_LSB(i));
138 			data->fan[i] |= smsc47b397_read_value(client,
139 					SMSC47B397_REG_FAN_MSB(i)) << 8;
140 		}
141 
142 		data->last_updated = jiffies;
143 		data->valid = 1;
144 
145 		dev_dbg(&client->dev, "... device update complete\n");
146 	}
147 
148 	mutex_unlock(&data->update_lock);
149 
150 	return data;
151 }
152 
153 /* TEMP: 0.001C/bit (-128C to +127C)
154    REG: 1C/bit, two's complement */
155 static int temp_from_reg(u8 reg)
156 {
157 	return (s8)reg * 1000;
158 }
159 
160 /* 0 <= nr <= 3 */
161 static ssize_t show_temp(struct device *dev, char *buf, int nr)
162 {
163 	struct smsc47b397_data *data = smsc47b397_update_device(dev);
164 	return sprintf(buf, "%d\n", temp_from_reg(data->temp[nr]));
165 }
166 
167 #define sysfs_temp(num) \
168 static ssize_t show_temp##num(struct device *dev, struct device_attribute *attr, char *buf) \
169 { \
170 	return show_temp(dev, buf, num-1); \
171 } \
172 static DEVICE_ATTR(temp##num##_input, S_IRUGO, show_temp##num, NULL)
173 
174 sysfs_temp(1);
175 sysfs_temp(2);
176 sysfs_temp(3);
177 sysfs_temp(4);
178 
179 /* FAN: 1 RPM/bit
180    REG: count of 90kHz pulses / revolution */
181 static int fan_from_reg(u16 reg)
182 {
183 	return 90000 * 60 / reg;
184 }
185 
186 /* 0 <= nr <= 3 */
187 static ssize_t show_fan(struct device *dev, char *buf, int nr)
188 {
189         struct smsc47b397_data *data = smsc47b397_update_device(dev);
190         return sprintf(buf, "%d\n", fan_from_reg(data->fan[nr]));
191 }
192 
193 #define sysfs_fan(num) \
194 static ssize_t show_fan##num(struct device *dev, struct device_attribute *attr, char *buf) \
195 { \
196 	return show_fan(dev, buf, num-1); \
197 } \
198 static DEVICE_ATTR(fan##num##_input, S_IRUGO, show_fan##num, NULL)
199 
200 sysfs_fan(1);
201 sysfs_fan(2);
202 sysfs_fan(3);
203 sysfs_fan(4);
204 
205 static struct attribute *smsc47b397_attributes[] = {
206 	&dev_attr_temp1_input.attr,
207 	&dev_attr_temp2_input.attr,
208 	&dev_attr_temp3_input.attr,
209 	&dev_attr_temp4_input.attr,
210 	&dev_attr_fan1_input.attr,
211 	&dev_attr_fan2_input.attr,
212 	&dev_attr_fan3_input.attr,
213 	&dev_attr_fan4_input.attr,
214 
215 	NULL
216 };
217 
218 static const struct attribute_group smsc47b397_group = {
219 	.attrs = smsc47b397_attributes,
220 };
221 
222 static int smsc47b397_detach_client(struct i2c_client *client)
223 {
224 	struct smsc47b397_data *data = i2c_get_clientdata(client);
225 	int err;
226 
227 	hwmon_device_unregister(data->class_dev);
228 	sysfs_remove_group(&client->dev.kobj, &smsc47b397_group);
229 
230 	if ((err = i2c_detach_client(client)))
231 		return err;
232 
233 	release_region(client->addr, SMSC_EXTENT);
234 	kfree(data);
235 
236 	return 0;
237 }
238 
239 static int smsc47b397_detect(struct i2c_adapter *adapter);
240 
241 static struct i2c_driver smsc47b397_driver = {
242 	.driver = {
243 		.owner	= THIS_MODULE,
244 		.name	= "smsc47b397",
245 	},
246 	.attach_adapter	= smsc47b397_detect,
247 	.detach_client	= smsc47b397_detach_client,
248 };
249 
250 static int smsc47b397_detect(struct i2c_adapter *adapter)
251 {
252 	struct i2c_client *new_client;
253 	struct smsc47b397_data *data;
254 	int err = 0;
255 
256 	if (!request_region(address, SMSC_EXTENT,
257 			    smsc47b397_driver.driver.name)) {
258 		dev_err(&adapter->dev, "Region 0x%x already in use!\n",
259 			address);
260 		return -EBUSY;
261 	}
262 
263 	if (!(data = kzalloc(sizeof(struct smsc47b397_data), GFP_KERNEL))) {
264 		err = -ENOMEM;
265 		goto error_release;
266 	}
267 
268 	new_client = &data->client;
269 	i2c_set_clientdata(new_client, data);
270 	new_client->addr = address;
271 	mutex_init(&data->lock);
272 	new_client->adapter = adapter;
273 	new_client->driver = &smsc47b397_driver;
274 	new_client->flags = 0;
275 
276 	strlcpy(new_client->name, "smsc47b397", I2C_NAME_SIZE);
277 
278 	mutex_init(&data->update_lock);
279 
280 	if ((err = i2c_attach_client(new_client)))
281 		goto error_free;
282 
283 	if ((err = sysfs_create_group(&new_client->dev.kobj, &smsc47b397_group)))
284 		goto error_detach;
285 
286 	data->class_dev = hwmon_device_register(&new_client->dev);
287 	if (IS_ERR(data->class_dev)) {
288 		err = PTR_ERR(data->class_dev);
289 		goto error_remove;
290 	}
291 
292 	return 0;
293 
294 error_remove:
295 	sysfs_remove_group(&new_client->dev.kobj, &smsc47b397_group);
296 error_detach:
297 	i2c_detach_client(new_client);
298 error_free:
299 	kfree(data);
300 error_release:
301 	release_region(address, SMSC_EXTENT);
302 	return err;
303 }
304 
305 static int __init smsc47b397_find(unsigned short *addr)
306 {
307 	u8 id, rev;
308 
309 	superio_enter();
310 	id = superio_inb(SUPERIO_REG_DEVID);
311 
312 	if ((id != 0x6f) && (id != 0x81)) {
313 		superio_exit();
314 		return -ENODEV;
315 	}
316 
317 	rev = superio_inb(SUPERIO_REG_DEVREV);
318 
319 	superio_select(SUPERIO_REG_LD8);
320 	*addr = (superio_inb(SUPERIO_REG_BASE_MSB) << 8)
321 		 |  superio_inb(SUPERIO_REG_BASE_LSB);
322 
323 	printk(KERN_INFO "smsc47b397: found SMSC %s "
324 		"(base address 0x%04x, revision %u)\n",
325 		id == 0x81 ? "SCH5307-NS" : "LPC47B397-NC", *addr, rev);
326 
327 	superio_exit();
328 	return 0;
329 }
330 
331 static int __init smsc47b397_init(void)
332 {
333 	int ret;
334 
335 	if ((ret = smsc47b397_find(&address)))
336 		return ret;
337 
338 	return i2c_isa_add_driver(&smsc47b397_driver);
339 }
340 
341 static void __exit smsc47b397_exit(void)
342 {
343 	i2c_isa_del_driver(&smsc47b397_driver);
344 }
345 
346 MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
347 MODULE_DESCRIPTION("SMSC LPC47B397 driver");
348 MODULE_LICENSE("GPL");
349 
350 module_init(smsc47b397_init);
351 module_exit(smsc47b397_exit);
352