kernel-ark/drivers/hwmon/smsc47b397.c
Jean Delvare 67b671bceb hwmon: Let the user override the detected Super-I/O device ID
While it is possible to force SMBus-based hardware monitoring chip
drivers to drive a not officially supported device, we do not have this
possibility for Super-I/O-based drivers. That's unfortunate because
sometimes newer chips are fully compatible and just forcing the driver
to load would work. Instead of that we have to tell the users to
recompile the kernel driver, which isn't an easy task for everyone.

So, I propose that we add a module parameter to all Super-I/O based
hardware monitoring drivers, letting advanced users force the driver
to load on their machine. The user has to provide the device ID of a
supposedly compatible device. This requires looking at the source code or
a datasheet, so I am confident that users can't randomly force a driver
without knowing what they are doing. Thus this should be relatively safe.

As you can see from the code, the implementation is pretty simple and
unintrusive.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Hans de Goede <j.w.r.degoede@hhs.nl>
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>
2008-02-07 20:39:42 -05:00

399 lines
9.7 KiB
C

/*
smsc47b397.c - Part of lm_sensors, Linux kernel modules
for hardware monitoring
Supports the SMSC LPC47B397-NC Super-I/O chip.
Author/Maintainer: Mark M. Hoffman <mhoffman@lightlink.com>
Copyright (C) 2004 Utilitek Systems, Inc.
derived in part from smsc47m1.c:
Copyright (C) 2002 Mark D. Studebaker <mdsxyz123@yahoo.com>
Copyright (C) 2004 Jean Delvare <khali@linux-fr.org>
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/module.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/jiffies.h>
#include <linux/platform_device.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/mutex.h>
#include <asm/io.h>
static unsigned short force_id;
module_param(force_id, ushort, 0);
MODULE_PARM_DESC(force_id, "Override the detected device ID");
static struct platform_device *pdev;
#define DRVNAME "smsc47b397"
/* Super-I/0 registers and commands */
#define REG 0x2e /* The register to read/write */
#define VAL 0x2f /* The value to read/write */
static inline void superio_outb(int reg, int val)
{
outb(reg, REG);
outb(val, VAL);
}
static inline int superio_inb(int reg)
{
outb(reg, REG);
return inb(VAL);
}
/* select superio logical device */
static inline void superio_select(int ld)
{
superio_outb(0x07, ld);
}
static inline void superio_enter(void)
{
outb(0x55, REG);
}
static inline void superio_exit(void)
{
outb(0xAA, REG);
}
#define SUPERIO_REG_DEVID 0x20
#define SUPERIO_REG_DEVREV 0x21
#define SUPERIO_REG_BASE_MSB 0x60
#define SUPERIO_REG_BASE_LSB 0x61
#define SUPERIO_REG_LD8 0x08
#define SMSC_EXTENT 0x02
/* 0 <= nr <= 3 */
static u8 smsc47b397_reg_temp[] = {0x25, 0x26, 0x27, 0x80};
#define SMSC47B397_REG_TEMP(nr) (smsc47b397_reg_temp[(nr)])
/* 0 <= nr <= 3 */
#define SMSC47B397_REG_FAN_LSB(nr) (0x28 + 2 * (nr))
#define SMSC47B397_REG_FAN_MSB(nr) (0x29 + 2 * (nr))
struct smsc47b397_data {
unsigned short addr;
const char *name;
struct device *hwmon_dev;
struct mutex lock;
struct mutex update_lock;
unsigned long last_updated; /* in jiffies */
int valid;
/* register values */
u16 fan[4];
u8 temp[4];
};
static int smsc47b397_read_value(struct smsc47b397_data* data, u8 reg)
{
int res;
mutex_lock(&data->lock);
outb(reg, data->addr);
res = inb_p(data->addr + 1);
mutex_unlock(&data->lock);
return res;
}
static struct smsc47b397_data *smsc47b397_update_device(struct device *dev)
{
struct smsc47b397_data *data = dev_get_drvdata(dev);
int i;
mutex_lock(&data->update_lock);
if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
dev_dbg(dev, "starting device update...\n");
/* 4 temperature inputs, 4 fan inputs */
for (i = 0; i < 4; i++) {
data->temp[i] = smsc47b397_read_value(data,
SMSC47B397_REG_TEMP(i));
/* must read LSB first */
data->fan[i] = smsc47b397_read_value(data,
SMSC47B397_REG_FAN_LSB(i));
data->fan[i] |= smsc47b397_read_value(data,
SMSC47B397_REG_FAN_MSB(i)) << 8;
}
data->last_updated = jiffies;
data->valid = 1;
dev_dbg(dev, "... device update complete\n");
}
mutex_unlock(&data->update_lock);
return data;
}
/* TEMP: 0.001C/bit (-128C to +127C)
REG: 1C/bit, two's complement */
static int temp_from_reg(u8 reg)
{
return (s8)reg * 1000;
}
static ssize_t show_temp(struct device *dev, struct device_attribute
*devattr, char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct smsc47b397_data *data = smsc47b397_update_device(dev);
return sprintf(buf, "%d\n", temp_from_reg(data->temp[attr->index]));
}
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
/* FAN: 1 RPM/bit
REG: count of 90kHz pulses / revolution */
static int fan_from_reg(u16 reg)
{
if (reg == 0 || reg == 0xffff)
return 0;
return 90000 * 60 / reg;
}
static ssize_t show_fan(struct device *dev, struct device_attribute
*devattr, char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct smsc47b397_data *data = smsc47b397_update_device(dev);
return sprintf(buf, "%d\n", fan_from_reg(data->fan[attr->index]));
}
static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, show_fan, NULL, 0);
static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, show_fan, NULL, 1);
static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, show_fan, NULL, 2);
static SENSOR_DEVICE_ATTR(fan4_input, S_IRUGO, show_fan, NULL, 3);
static ssize_t show_name(struct device *dev, struct device_attribute
*devattr, char *buf)
{
struct smsc47b397_data *data = dev_get_drvdata(dev);
return sprintf(buf, "%s\n", data->name);
}
static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
static struct attribute *smsc47b397_attributes[] = {
&sensor_dev_attr_temp1_input.dev_attr.attr,
&sensor_dev_attr_temp2_input.dev_attr.attr,
&sensor_dev_attr_temp3_input.dev_attr.attr,
&sensor_dev_attr_temp4_input.dev_attr.attr,
&sensor_dev_attr_fan1_input.dev_attr.attr,
&sensor_dev_attr_fan2_input.dev_attr.attr,
&sensor_dev_attr_fan3_input.dev_attr.attr,
&sensor_dev_attr_fan4_input.dev_attr.attr,
&dev_attr_name.attr,
NULL
};
static const struct attribute_group smsc47b397_group = {
.attrs = smsc47b397_attributes,
};
static int __devexit smsc47b397_remove(struct platform_device *pdev)
{
struct smsc47b397_data *data = platform_get_drvdata(pdev);
struct resource *res;
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&pdev->dev.kobj, &smsc47b397_group);
res = platform_get_resource(pdev, IORESOURCE_IO, 0);
release_region(res->start, SMSC_EXTENT);
kfree(data);
return 0;
}
static int smsc47b397_probe(struct platform_device *pdev);
static struct platform_driver smsc47b397_driver = {
.driver = {
.owner = THIS_MODULE,
.name = DRVNAME,
},
.probe = smsc47b397_probe,
.remove = __devexit_p(smsc47b397_remove),
};
static int __devinit smsc47b397_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct smsc47b397_data *data;
struct resource *res;
int err = 0;
res = platform_get_resource(pdev, IORESOURCE_IO, 0);
if (!request_region(res->start, SMSC_EXTENT,
smsc47b397_driver.driver.name)) {
dev_err(dev, "Region 0x%lx-0x%lx already in use!\n",
(unsigned long)res->start,
(unsigned long)res->start + SMSC_EXTENT - 1);
return -EBUSY;
}
if (!(data = kzalloc(sizeof(struct smsc47b397_data), GFP_KERNEL))) {
err = -ENOMEM;
goto error_release;
}
data->addr = res->start;
data->name = "smsc47b397";
mutex_init(&data->lock);
mutex_init(&data->update_lock);
platform_set_drvdata(pdev, data);
if ((err = sysfs_create_group(&dev->kobj, &smsc47b397_group)))
goto error_free;
data->hwmon_dev = hwmon_device_register(dev);
if (IS_ERR(data->hwmon_dev)) {
err = PTR_ERR(data->hwmon_dev);
goto error_remove;
}
return 0;
error_remove:
sysfs_remove_group(&dev->kobj, &smsc47b397_group);
error_free:
kfree(data);
error_release:
release_region(res->start, SMSC_EXTENT);
return err;
}
static int __init smsc47b397_device_add(unsigned short address)
{
struct resource res = {
.start = address,
.end = address + SMSC_EXTENT - 1,
.name = DRVNAME,
.flags = IORESOURCE_IO,
};
int err;
pdev = platform_device_alloc(DRVNAME, address);
if (!pdev) {
err = -ENOMEM;
printk(KERN_ERR DRVNAME ": Device allocation failed\n");
goto exit;
}
err = platform_device_add_resources(pdev, &res, 1);
if (err) {
printk(KERN_ERR DRVNAME ": Device resource addition failed "
"(%d)\n", err);
goto exit_device_put;
}
err = platform_device_add(pdev);
if (err) {
printk(KERN_ERR DRVNAME ": Device addition failed (%d)\n",
err);
goto exit_device_put;
}
return 0;
exit_device_put:
platform_device_put(pdev);
exit:
return err;
}
static int __init smsc47b397_find(unsigned short *addr)
{
u8 id, rev;
superio_enter();
id = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);
if ((id != 0x6f) && (id != 0x81) && (id != 0x85)) {
superio_exit();
return -ENODEV;
}
rev = superio_inb(SUPERIO_REG_DEVREV);
superio_select(SUPERIO_REG_LD8);
*addr = (superio_inb(SUPERIO_REG_BASE_MSB) << 8)
| superio_inb(SUPERIO_REG_BASE_LSB);
printk(KERN_INFO DRVNAME ": found SMSC %s "
"(base address 0x%04x, revision %u)\n",
id == 0x81 ? "SCH5307-NS" : id == 0x85 ? "SCH5317" :
"LPC47B397-NC", *addr, rev);
superio_exit();
return 0;
}
static int __init smsc47b397_init(void)
{
unsigned short address;
int ret;
if ((ret = smsc47b397_find(&address)))
return ret;
ret = platform_driver_register(&smsc47b397_driver);
if (ret)
goto exit;
/* Sets global pdev as a side effect */
ret = smsc47b397_device_add(address);
if (ret)
goto exit_driver;
return 0;
exit_driver:
platform_driver_unregister(&smsc47b397_driver);
exit:
return ret;
}
static void __exit smsc47b397_exit(void)
{
platform_device_unregister(pdev);
platform_driver_unregister(&smsc47b397_driver);
}
MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
MODULE_DESCRIPTION("SMSC LPC47B397 driver");
MODULE_LICENSE("GPL");
module_init(smsc47b397_init);
module_exit(smsc47b397_exit);