Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity
kernel-fxtec-pro1x/drivers/hwmon/smsc47b397.c
Guenter Roeck 48b31e8a02 hwmon: (smsc47b397) Use request_muxed_region for Super-IO accesses 
[ Upstream commit 8c0826756744c0ac1df600a5e4cca1a341b13101 ]

Super-IO accesses may fail on a system with no or unmapped LPC bus.

Also, other drivers may attempt to access the LPC bus at the same time,
resulting in undefined behavior.

Use request_muxed_region() to ensure that IO access on the requested
address space is supported, and to ensure that access by multiple drivers
is synchronized.

Fixes: 8d5d45fb14 ("I2C: Move hwmon drivers (2/3)")
Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reported-by: John Garry <john.garry@huawei.com>
Cc: John Garry <john.garry@huawei.com>
Acked-by: John Garry <john.garry@huawei.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31 06:46:22 -07:00

383 lines
8.9 KiB
C
Raw Blame History

/*
* 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 <jdelvare@suse.de>
*
* 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.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#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 <linux/acpi.h>
#include <linux/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 int superio_enter(void)
{
if (!request_muxed_region(REG, 2, DRVNAME))
return -EBUSY;
outb(0x55, REG);
return 0;
}
static inline void superio_exit(void)
{
outb(0xAA, REG);
release_region(REG, 2);
}
#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;
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 struct attribute *smsc47b397_attrs[] = {
&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,
NULL
};
ATTRIBUTE_GROUPS(smsc47b397);
static int smsc47b397_probe(struct platform_device *pdev);
static struct platform_driver smsc47b397_driver = {
.driver = {
.name = DRVNAME,
},
.probe = smsc47b397_probe,
};
static int smsc47b397_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct smsc47b397_data *data;
struct device *hwmon_dev;
struct resource *res;
res = platform_get_resource(pdev, IORESOURCE_IO, 0);
if (!devm_request_region(dev, 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;
}
data = devm_kzalloc(dev, sizeof(struct smsc47b397_data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->addr = res->start;
mutex_init(&data->lock);
mutex_init(&data->update_lock);
hwmon_dev = devm_hwmon_device_register_with_groups(dev, "smsc47b397",
data,
smsc47b397_groups);
return PTR_ERR_OR_ZERO(hwmon_dev);
}
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;
err = acpi_check_resource_conflict(&res);
if (err)
goto exit;
pdev = platform_device_alloc(DRVNAME, address);
if (!pdev) {
err = -ENOMEM;
pr_err("Device allocation failed\n");
goto exit;
}
err = platform_device_add_resources(pdev, &res, 1);
if (err) {
pr_err("Device resource addition failed (%d)\n", err);
goto exit_device_put;
}
err = platform_device_add(pdev);
if (err) {
pr_err("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(void)
{
u8 id, rev;
char *name;
unsigned short addr;
int err;
err = superio_enter();
if (err)
return err;
id = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);
switch (id) {
case 0x81:
name = "SCH5307-NS";
break;
case 0x6f:
name = "LPC47B397-NC";
break;
case 0x85:
case 0x8c:
name = "SCH5317";
break;
default:
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);
pr_info("found SMSC %s (base address 0x%04x, revision %u)\n",
name, addr, rev);
superio_exit();
return addr;
}
static int __init smsc47b397_init(void)
{
unsigned short address;
int ret;
ret = smsc47b397_find();
if (ret < 0)
return ret;
address = 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);
Reference in a new issue View git blame Copy permalink