xref: /openbmc/linux/drivers/hwmon/smsc47b397.c (revision 87c2ce3b)
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 <asm/io.h>
39 
40 /* Address is autodetected, there is no default value */
41 static unsigned short address;
42 
43 /* Super-I/0 registers and commands */
44 
45 #define	REG	0x2e	/* The register to read/write */
46 #define	VAL	0x2f	/* The value to read/write */
47 
48 static inline void superio_outb(int reg, int val)
49 {
50 	outb(reg, REG);
51 	outb(val, VAL);
52 }
53 
54 static inline int superio_inb(int reg)
55 {
56 	outb(reg, REG);
57 	return inb(VAL);
58 }
59 
60 /* select superio logical device */
61 static inline void superio_select(int ld)
62 {
63 	superio_outb(0x07, ld);
64 }
65 
66 static inline void superio_enter(void)
67 {
68 	outb(0x55, REG);
69 }
70 
71 static inline void superio_exit(void)
72 {
73 	outb(0xAA, REG);
74 }
75 
76 #define SUPERIO_REG_DEVID	0x20
77 #define SUPERIO_REG_DEVREV	0x21
78 #define SUPERIO_REG_BASE_MSB	0x60
79 #define SUPERIO_REG_BASE_LSB	0x61
80 #define SUPERIO_REG_LD8		0x08
81 
82 #define SMSC_EXTENT		0x02
83 
84 /* 0 <= nr <= 3 */
85 static u8 smsc47b397_reg_temp[] = {0x25, 0x26, 0x27, 0x80};
86 #define SMSC47B397_REG_TEMP(nr)	(smsc47b397_reg_temp[(nr)])
87 
88 /* 0 <= nr <= 3 */
89 #define SMSC47B397_REG_FAN_LSB(nr) (0x28 + 2 * (nr))
90 #define SMSC47B397_REG_FAN_MSB(nr) (0x29 + 2 * (nr))
91 
92 struct smsc47b397_data {
93 	struct i2c_client client;
94 	struct class_device *class_dev;
95 	struct semaphore lock;
96 
97 	struct semaphore update_lock;
98 	unsigned long last_updated; /* in jiffies */
99 	int valid;
100 
101 	/* register values */
102 	u16 fan[4];
103 	u8 temp[4];
104 };
105 
106 static int smsc47b397_read_value(struct i2c_client *client, u8 reg)
107 {
108 	struct smsc47b397_data *data = i2c_get_clientdata(client);
109 	int res;
110 
111 	down(&data->lock);
112 	outb(reg, client->addr);
113 	res = inb_p(client->addr + 1);
114 	up(&data->lock);
115 	return res;
116 }
117 
118 static struct smsc47b397_data *smsc47b397_update_device(struct device *dev)
119 {
120  	struct i2c_client *client = to_i2c_client(dev);
121 	struct smsc47b397_data *data = i2c_get_clientdata(client);
122 	int i;
123 
124 	down(&data->update_lock);
125 
126 	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
127 		dev_dbg(&client->dev, "starting device update...\n");
128 
129 		/* 4 temperature inputs, 4 fan inputs */
130 		for (i = 0; i < 4; i++) {
131 			data->temp[i] = smsc47b397_read_value(client,
132 					SMSC47B397_REG_TEMP(i));
133 
134 			/* must read LSB first */
135 			data->fan[i]  = smsc47b397_read_value(client,
136 					SMSC47B397_REG_FAN_LSB(i));
137 			data->fan[i] |= smsc47b397_read_value(client,
138 					SMSC47B397_REG_FAN_MSB(i)) << 8;
139 		}
140 
141 		data->last_updated = jiffies;
142 		data->valid = 1;
143 
144 		dev_dbg(&client->dev, "... device update complete\n");
145 	}
146 
147 	up(&data->update_lock);
148 
149 	return data;
150 }
151 
152 /* TEMP: 0.001C/bit (-128C to +127C)
153    REG: 1C/bit, two's complement */
154 static int temp_from_reg(u8 reg)
155 {
156 	return (s8)reg * 1000;
157 }
158 
159 /* 0 <= nr <= 3 */
160 static ssize_t show_temp(struct device *dev, char *buf, int nr)
161 {
162 	struct smsc47b397_data *data = smsc47b397_update_device(dev);
163 	return sprintf(buf, "%d\n", temp_from_reg(data->temp[nr]));
164 }
165 
166 #define sysfs_temp(num) \
167 static ssize_t show_temp##num(struct device *dev, struct device_attribute *attr, char *buf) \
168 { \
169 	return show_temp(dev, buf, num-1); \
170 } \
171 static DEVICE_ATTR(temp##num##_input, S_IRUGO, show_temp##num, NULL)
172 
173 sysfs_temp(1);
174 sysfs_temp(2);
175 sysfs_temp(3);
176 sysfs_temp(4);
177 
178 #define device_create_file_temp(client, num) \
179 	device_create_file(&client->dev, &dev_attr_temp##num##_input)
180 
181 /* FAN: 1 RPM/bit
182    REG: count of 90kHz pulses / revolution */
183 static int fan_from_reg(u16 reg)
184 {
185 	return 90000 * 60 / reg;
186 }
187 
188 /* 0 <= nr <= 3 */
189 static ssize_t show_fan(struct device *dev, char *buf, int nr)
190 {
191         struct smsc47b397_data *data = smsc47b397_update_device(dev);
192         return sprintf(buf, "%d\n", fan_from_reg(data->fan[nr]));
193 }
194 
195 #define sysfs_fan(num) \
196 static ssize_t show_fan##num(struct device *dev, struct device_attribute *attr, char *buf) \
197 { \
198 	return show_fan(dev, buf, num-1); \
199 } \
200 static DEVICE_ATTR(fan##num##_input, S_IRUGO, show_fan##num, NULL)
201 
202 sysfs_fan(1);
203 sysfs_fan(2);
204 sysfs_fan(3);
205 sysfs_fan(4);
206 
207 #define device_create_file_fan(client, num) \
208 	device_create_file(&client->dev, &dev_attr_fan##num##_input)
209 
210 static int smsc47b397_detach_client(struct i2c_client *client)
211 {
212 	struct smsc47b397_data *data = i2c_get_clientdata(client);
213 	int err;
214 
215 	hwmon_device_unregister(data->class_dev);
216 
217 	if ((err = i2c_detach_client(client)))
218 		return err;
219 
220 	release_region(client->addr, SMSC_EXTENT);
221 	kfree(data);
222 
223 	return 0;
224 }
225 
226 static int smsc47b397_detect(struct i2c_adapter *adapter);
227 
228 static struct i2c_driver smsc47b397_driver = {
229 	.driver = {
230 		.name	= "smsc47b397",
231 	},
232 	.attach_adapter	= smsc47b397_detect,
233 	.detach_client	= smsc47b397_detach_client,
234 };
235 
236 static int smsc47b397_detect(struct i2c_adapter *adapter)
237 {
238 	struct i2c_client *new_client;
239 	struct smsc47b397_data *data;
240 	int err = 0;
241 
242 	if (!request_region(address, SMSC_EXTENT,
243 			    smsc47b397_driver.driver.name)) {
244 		dev_err(&adapter->dev, "Region 0x%x already in use!\n",
245 			address);
246 		return -EBUSY;
247 	}
248 
249 	if (!(data = kzalloc(sizeof(struct smsc47b397_data), GFP_KERNEL))) {
250 		err = -ENOMEM;
251 		goto error_release;
252 	}
253 
254 	new_client = &data->client;
255 	i2c_set_clientdata(new_client, data);
256 	new_client->addr = address;
257 	init_MUTEX(&data->lock);
258 	new_client->adapter = adapter;
259 	new_client->driver = &smsc47b397_driver;
260 	new_client->flags = 0;
261 
262 	strlcpy(new_client->name, "smsc47b397", I2C_NAME_SIZE);
263 
264 	init_MUTEX(&data->update_lock);
265 
266 	if ((err = i2c_attach_client(new_client)))
267 		goto error_free;
268 
269 	data->class_dev = hwmon_device_register(&new_client->dev);
270 	if (IS_ERR(data->class_dev)) {
271 		err = PTR_ERR(data->class_dev);
272 		goto error_detach;
273 	}
274 
275 	device_create_file_temp(new_client, 1);
276 	device_create_file_temp(new_client, 2);
277 	device_create_file_temp(new_client, 3);
278 	device_create_file_temp(new_client, 4);
279 
280 	device_create_file_fan(new_client, 1);
281 	device_create_file_fan(new_client, 2);
282 	device_create_file_fan(new_client, 3);
283 	device_create_file_fan(new_client, 4);
284 
285 	return 0;
286 
287 error_detach:
288 	i2c_detach_client(new_client);
289 error_free:
290 	kfree(data);
291 error_release:
292 	release_region(address, SMSC_EXTENT);
293 	return err;
294 }
295 
296 static int __init smsc47b397_find(unsigned short *addr)
297 {
298 	u8 id, rev;
299 
300 	superio_enter();
301 	id = superio_inb(SUPERIO_REG_DEVID);
302 
303 	if ((id != 0x6f) && (id != 0x81)) {
304 		superio_exit();
305 		return -ENODEV;
306 	}
307 
308 	rev = superio_inb(SUPERIO_REG_DEVREV);
309 
310 	superio_select(SUPERIO_REG_LD8);
311 	*addr = (superio_inb(SUPERIO_REG_BASE_MSB) << 8)
312 		 |  superio_inb(SUPERIO_REG_BASE_LSB);
313 
314 	printk(KERN_INFO "smsc47b397: found SMSC %s "
315 		"(base address 0x%04x, revision %u)\n",
316 		id == 0x81 ? "SCH5307-NS" : "LPC47B397-NC", *addr, rev);
317 
318 	superio_exit();
319 	return 0;
320 }
321 
322 static int __init smsc47b397_init(void)
323 {
324 	int ret;
325 
326 	if ((ret = smsc47b397_find(&address)))
327 		return ret;
328 
329 	return i2c_isa_add_driver(&smsc47b397_driver);
330 }
331 
332 static void __exit smsc47b397_exit(void)
333 {
334 	i2c_isa_del_driver(&smsc47b397_driver);
335 }
336 
337 MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
338 MODULE_DESCRIPTION("SMSC LPC47B397 driver");
339 MODULE_LICENSE("GPL");
340 
341 module_init(smsc47b397_init);
342 module_exit(smsc47b397_exit);
343