befs: Validate length of long symbolic links.
[linux-2.6/kvm.git] / drivers / hwmon / smsc47b397.c
blob9fb7516e6f451284419559fdf4faf3e8fffbeaf9
1 /*
2 smsc47b397.c - Part of lm_sensors, Linux kernel modules
3 for hardware monitoring
5 Supports the SMSC LPC47B397-NC Super-I/O chip.
7 Author/Maintainer: Mark M. Hoffman <mhoffman@lightlink.com>
8 Copyright (C) 2004 Utilitek Systems, Inc.
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>
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.
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.
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.
29 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
31 #include <linux/module.h>
32 #include <linux/slab.h>
33 #include <linux/ioport.h>
34 #include <linux/jiffies.h>
35 #include <linux/platform_device.h>
36 #include <linux/hwmon.h>
37 #include <linux/hwmon-sysfs.h>
38 #include <linux/err.h>
39 #include <linux/init.h>
40 #include <linux/mutex.h>
41 #include <linux/acpi.h>
42 #include <linux/io.h>
44 static unsigned short force_id;
45 module_param(force_id, ushort, 0);
46 MODULE_PARM_DESC(force_id, "Override the detected device ID");
48 static struct platform_device *pdev;
50 #define DRVNAME "smsc47b397"
52 /* Super-I/0 registers and commands */
54 #define REG 0x2e /* The register to read/write */
55 #define VAL 0x2f /* The value to read/write */
57 static inline void superio_outb(int reg, int val)
59 outb(reg, REG);
60 outb(val, VAL);
63 static inline int superio_inb(int reg)
65 outb(reg, REG);
66 return inb(VAL);
69 /* select superio logical device */
70 static inline void superio_select(int ld)
72 superio_outb(0x07, ld);
75 static inline void superio_enter(void)
77 outb(0x55, REG);
80 static inline void superio_exit(void)
82 outb(0xAA, REG);
85 #define SUPERIO_REG_DEVID 0x20
86 #define SUPERIO_REG_DEVREV 0x21
87 #define SUPERIO_REG_BASE_MSB 0x60
88 #define SUPERIO_REG_BASE_LSB 0x61
89 #define SUPERIO_REG_LD8 0x08
91 #define SMSC_EXTENT 0x02
93 /* 0 <= nr <= 3 */
94 static u8 smsc47b397_reg_temp[] = {0x25, 0x26, 0x27, 0x80};
95 #define SMSC47B397_REG_TEMP(nr) (smsc47b397_reg_temp[(nr)])
97 /* 0 <= nr <= 3 */
98 #define SMSC47B397_REG_FAN_LSB(nr) (0x28 + 2 * (nr))
99 #define SMSC47B397_REG_FAN_MSB(nr) (0x29 + 2 * (nr))
101 struct smsc47b397_data {
102 unsigned short addr;
103 const char *name;
104 struct device *hwmon_dev;
105 struct mutex lock;
107 struct mutex update_lock;
108 unsigned long last_updated; /* in jiffies */
109 int valid;
111 /* register values */
112 u16 fan[4];
113 u8 temp[4];
116 static int smsc47b397_read_value(struct smsc47b397_data* data, u8 reg)
118 int res;
120 mutex_lock(&data->lock);
121 outb(reg, data->addr);
122 res = inb_p(data->addr + 1);
123 mutex_unlock(&data->lock);
124 return res;
127 static struct smsc47b397_data *smsc47b397_update_device(struct device *dev)
129 struct smsc47b397_data *data = dev_get_drvdata(dev);
130 int i;
132 mutex_lock(&data->update_lock);
134 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
135 dev_dbg(dev, "starting device update...\n");
137 /* 4 temperature inputs, 4 fan inputs */
138 for (i = 0; i < 4; i++) {
139 data->temp[i] = smsc47b397_read_value(data,
140 SMSC47B397_REG_TEMP(i));
142 /* must read LSB first */
143 data->fan[i] = smsc47b397_read_value(data,
144 SMSC47B397_REG_FAN_LSB(i));
145 data->fan[i] |= smsc47b397_read_value(data,
146 SMSC47B397_REG_FAN_MSB(i)) << 8;
149 data->last_updated = jiffies;
150 data->valid = 1;
152 dev_dbg(dev, "... device update complete\n");
155 mutex_unlock(&data->update_lock);
157 return data;
160 /* TEMP: 0.001C/bit (-128C to +127C)
161 REG: 1C/bit, two's complement */
162 static int temp_from_reg(u8 reg)
164 return (s8)reg * 1000;
167 static ssize_t show_temp(struct device *dev, struct device_attribute
168 *devattr, char *buf)
170 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
171 struct smsc47b397_data *data = smsc47b397_update_device(dev);
172 return sprintf(buf, "%d\n", temp_from_reg(data->temp[attr->index]));
175 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
176 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
177 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
178 static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
180 /* FAN: 1 RPM/bit
181 REG: count of 90kHz pulses / revolution */
182 static int fan_from_reg(u16 reg)
184 if (reg == 0 || reg == 0xffff)
185 return 0;
186 return 90000 * 60 / reg;
189 static ssize_t show_fan(struct device *dev, struct device_attribute
190 *devattr, char *buf)
192 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
193 struct smsc47b397_data *data = smsc47b397_update_device(dev);
194 return sprintf(buf, "%d\n", fan_from_reg(data->fan[attr->index]));
196 static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, show_fan, NULL, 0);
197 static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, show_fan, NULL, 1);
198 static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, show_fan, NULL, 2);
199 static SENSOR_DEVICE_ATTR(fan4_input, S_IRUGO, show_fan, NULL, 3);
201 static ssize_t show_name(struct device *dev, struct device_attribute
202 *devattr, char *buf)
204 struct smsc47b397_data *data = dev_get_drvdata(dev);
205 return sprintf(buf, "%s\n", data->name);
207 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
209 static struct attribute *smsc47b397_attributes[] = {
210 &sensor_dev_attr_temp1_input.dev_attr.attr,
211 &sensor_dev_attr_temp2_input.dev_attr.attr,
212 &sensor_dev_attr_temp3_input.dev_attr.attr,
213 &sensor_dev_attr_temp4_input.dev_attr.attr,
214 &sensor_dev_attr_fan1_input.dev_attr.attr,
215 &sensor_dev_attr_fan2_input.dev_attr.attr,
216 &sensor_dev_attr_fan3_input.dev_attr.attr,
217 &sensor_dev_attr_fan4_input.dev_attr.attr,
219 &dev_attr_name.attr,
220 NULL
223 static const struct attribute_group smsc47b397_group = {
224 .attrs = smsc47b397_attributes,
227 static int __devexit smsc47b397_remove(struct platform_device *pdev)
229 struct smsc47b397_data *data = platform_get_drvdata(pdev);
230 struct resource *res;
232 hwmon_device_unregister(data->hwmon_dev);
233 sysfs_remove_group(&pdev->dev.kobj, &smsc47b397_group);
234 res = platform_get_resource(pdev, IORESOURCE_IO, 0);
235 release_region(res->start, SMSC_EXTENT);
236 kfree(data);
238 return 0;
241 static int smsc47b397_probe(struct platform_device *pdev);
243 static struct platform_driver smsc47b397_driver = {
244 .driver = {
245 .owner = THIS_MODULE,
246 .name = DRVNAME,
248 .probe = smsc47b397_probe,
249 .remove = __devexit_p(smsc47b397_remove),
252 static int __devinit smsc47b397_probe(struct platform_device *pdev)
254 struct device *dev = &pdev->dev;
255 struct smsc47b397_data *data;
256 struct resource *res;
257 int err = 0;
259 res = platform_get_resource(pdev, IORESOURCE_IO, 0);
260 if (!request_region(res->start, SMSC_EXTENT,
261 smsc47b397_driver.driver.name)) {
262 dev_err(dev, "Region 0x%lx-0x%lx already in use!\n",
263 (unsigned long)res->start,
264 (unsigned long)res->start + SMSC_EXTENT - 1);
265 return -EBUSY;
268 if (!(data = kzalloc(sizeof(struct smsc47b397_data), GFP_KERNEL))) {
269 err = -ENOMEM;
270 goto error_release;
273 data->addr = res->start;
274 data->name = "smsc47b397";
275 mutex_init(&data->lock);
276 mutex_init(&data->update_lock);
277 platform_set_drvdata(pdev, data);
279 if ((err = sysfs_create_group(&dev->kobj, &smsc47b397_group)))
280 goto error_free;
282 data->hwmon_dev = hwmon_device_register(dev);
283 if (IS_ERR(data->hwmon_dev)) {
284 err = PTR_ERR(data->hwmon_dev);
285 goto error_remove;
288 return 0;
290 error_remove:
291 sysfs_remove_group(&dev->kobj, &smsc47b397_group);
292 error_free:
293 kfree(data);
294 error_release:
295 release_region(res->start, SMSC_EXTENT);
296 return err;
299 static int __init smsc47b397_device_add(unsigned short address)
301 struct resource res = {
302 .start = address,
303 .end = address + SMSC_EXTENT - 1,
304 .name = DRVNAME,
305 .flags = IORESOURCE_IO,
307 int err;
309 err = acpi_check_resource_conflict(&res);
310 if (err)
311 goto exit;
313 pdev = platform_device_alloc(DRVNAME, address);
314 if (!pdev) {
315 err = -ENOMEM;
316 pr_err("Device allocation failed\n");
317 goto exit;
320 err = platform_device_add_resources(pdev, &res, 1);
321 if (err) {
322 pr_err("Device resource addition failed (%d)\n", err);
323 goto exit_device_put;
326 err = platform_device_add(pdev);
327 if (err) {
328 pr_err("Device addition failed (%d)\n", err);
329 goto exit_device_put;
332 return 0;
334 exit_device_put:
335 platform_device_put(pdev);
336 exit:
337 return err;
340 static int __init smsc47b397_find(unsigned short *addr)
342 u8 id, rev;
343 char *name;
345 superio_enter();
346 id = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);
348 switch(id) {
349 case 0x81:
350 name = "SCH5307-NS";
351 break;
352 case 0x6f:
353 name = "LPC47B397-NC";
354 break;
355 case 0x85:
356 case 0x8c:
357 name = "SCH5317";
358 break;
359 default:
360 superio_exit();
361 return -ENODEV;
364 rev = superio_inb(SUPERIO_REG_DEVREV);
366 superio_select(SUPERIO_REG_LD8);
367 *addr = (superio_inb(SUPERIO_REG_BASE_MSB) << 8)
368 | superio_inb(SUPERIO_REG_BASE_LSB);
370 pr_info("found SMSC %s (base address 0x%04x, revision %u)\n",
371 name, *addr, rev);
373 superio_exit();
374 return 0;
377 static int __init smsc47b397_init(void)
379 unsigned short address;
380 int ret;
382 if ((ret = smsc47b397_find(&address)))
383 return ret;
385 ret = platform_driver_register(&smsc47b397_driver);
386 if (ret)
387 goto exit;
389 /* Sets global pdev as a side effect */
390 ret = smsc47b397_device_add(address);
391 if (ret)
392 goto exit_driver;
394 return 0;
396 exit_driver:
397 platform_driver_unregister(&smsc47b397_driver);
398 exit:
399 return ret;
402 static void __exit smsc47b397_exit(void)
404 platform_device_unregister(pdev);
405 platform_driver_unregister(&smsc47b397_driver);
408 MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
409 MODULE_DESCRIPTION("SMSC LPC47B397 driver");
410 MODULE_LICENSE("GPL");
412 module_init(smsc47b397_init);
413 module_exit(smsc47b397_exit);