Revision 3f0116c3238a96bc18ad4b4acefe4e7be32fa861 authored by Ingo Molnar on 10 October 2013, 08:16:30 UTC, committed by Ingo Molnar on 11 October 2013, 05:39:14 UTC
Fengguang Wu, Oleg Nesterov and Peter Zijlstra tracked down a kernel crash to a GCC bug: GCC miscompiles certain 'asm goto' constructs, as outlined here: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670 Implement a workaround suggested by Jakub Jelinek. Reported-and-tested-by: Fengguang Wu <fengguang.wu@intel.com> Reported-by: Oleg Nesterov <oleg@redhat.com> Reported-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Suggested-by: Jakub Jelinek <jakub@redhat.com> Reviewed-by: Richard Henderson <rth@twiddle.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: <stable@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
1 parent 2fe80d3
max1619.c
/*
* max1619.c - Part of lm_sensors, Linux kernel modules for hardware
* monitoring
* Copyright (C) 2003-2004 Oleksij Rempel <bug-track@fisher-privat.net>
* Jean Delvare <khali@linux-fr.org>
*
* Based on the lm90 driver. The MAX1619 is a sensor chip made by Maxim.
* It reports up to two temperatures (its own plus up to
* one external one). Complete datasheet can be
* obtained from Maxim's website at:
* http://pdfserv.maxim-ic.com/en/ds/MAX1619.pdf
*
* 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/init.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/sysfs.h>
static const unsigned short normal_i2c[] = {
0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
/*
* The MAX1619 registers
*/
#define MAX1619_REG_R_MAN_ID 0xFE
#define MAX1619_REG_R_CHIP_ID 0xFF
#define MAX1619_REG_R_CONFIG 0x03
#define MAX1619_REG_W_CONFIG 0x09
#define MAX1619_REG_R_CONVRATE 0x04
#define MAX1619_REG_W_CONVRATE 0x0A
#define MAX1619_REG_R_STATUS 0x02
#define MAX1619_REG_R_LOCAL_TEMP 0x00
#define MAX1619_REG_R_REMOTE_TEMP 0x01
#define MAX1619_REG_R_REMOTE_HIGH 0x07
#define MAX1619_REG_W_REMOTE_HIGH 0x0D
#define MAX1619_REG_R_REMOTE_LOW 0x08
#define MAX1619_REG_W_REMOTE_LOW 0x0E
#define MAX1619_REG_R_REMOTE_CRIT 0x10
#define MAX1619_REG_W_REMOTE_CRIT 0x12
#define MAX1619_REG_R_TCRIT_HYST 0x11
#define MAX1619_REG_W_TCRIT_HYST 0x13
/*
* Conversions
*/
static int temp_from_reg(int val)
{
return (val & 0x80 ? val-0x100 : val) * 1000;
}
static int temp_to_reg(int val)
{
return (val < 0 ? val+0x100*1000 : val) / 1000;
}
/*
* Functions declaration
*/
static int max1619_probe(struct i2c_client *client,
const struct i2c_device_id *id);
static int max1619_detect(struct i2c_client *client,
struct i2c_board_info *info);
static void max1619_init_client(struct i2c_client *client);
static int max1619_remove(struct i2c_client *client);
static struct max1619_data *max1619_update_device(struct device *dev);
/*
* Driver data (common to all clients)
*/
static const struct i2c_device_id max1619_id[] = {
{ "max1619", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, max1619_id);
static struct i2c_driver max1619_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "max1619",
},
.probe = max1619_probe,
.remove = max1619_remove,
.id_table = max1619_id,
.detect = max1619_detect,
.address_list = normal_i2c,
};
/*
* Client data (each client gets its own)
*/
struct max1619_data {
struct device *hwmon_dev;
struct mutex update_lock;
char valid; /* zero until following fields are valid */
unsigned long last_updated; /* in jiffies */
/* registers values */
u8 temp_input1; /* local */
u8 temp_input2, temp_low2, temp_high2; /* remote */
u8 temp_crit2;
u8 temp_hyst2;
u8 alarms;
};
/*
* Sysfs stuff
*/
#define show_temp(value) \
static ssize_t show_##value(struct device *dev, struct device_attribute *attr, \
char *buf) \
{ \
struct max1619_data *data = max1619_update_device(dev); \
return sprintf(buf, "%d\n", temp_from_reg(data->value)); \
}
show_temp(temp_input1);
show_temp(temp_input2);
show_temp(temp_low2);
show_temp(temp_high2);
show_temp(temp_crit2);
show_temp(temp_hyst2);
#define set_temp2(value, reg) \
static ssize_t set_##value(struct device *dev, struct device_attribute *attr, \
const char *buf, \
size_t count) \
{ \
struct i2c_client *client = to_i2c_client(dev); \
struct max1619_data *data = i2c_get_clientdata(client); \
long val; \
int err = kstrtol(buf, 10, &val); \
if (err) \
return err; \
\
mutex_lock(&data->update_lock); \
data->value = temp_to_reg(val); \
i2c_smbus_write_byte_data(client, reg, data->value); \
mutex_unlock(&data->update_lock); \
return count; \
}
set_temp2(temp_low2, MAX1619_REG_W_REMOTE_LOW);
set_temp2(temp_high2, MAX1619_REG_W_REMOTE_HIGH);
set_temp2(temp_crit2, MAX1619_REG_W_REMOTE_CRIT);
set_temp2(temp_hyst2, MAX1619_REG_W_TCRIT_HYST);
static ssize_t show_alarms(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct max1619_data *data = max1619_update_device(dev);
return sprintf(buf, "%d\n", data->alarms);
}
static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
char *buf)
{
int bitnr = to_sensor_dev_attr(attr)->index;
struct max1619_data *data = max1619_update_device(dev);
return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
}
static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
static DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input2, NULL);
static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_low2,
set_temp_low2);
static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_high2,
set_temp_high2);
static DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit2,
set_temp_crit2);
static DEVICE_ATTR(temp2_crit_hyst, S_IWUSR | S_IRUGO, show_temp_hyst2,
set_temp_hyst2);
static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 1);
static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 2);
static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_alarm, NULL, 3);
static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 4);
static struct attribute *max1619_attributes[] = {
&dev_attr_temp1_input.attr,
&dev_attr_temp2_input.attr,
&dev_attr_temp2_min.attr,
&dev_attr_temp2_max.attr,
&dev_attr_temp2_crit.attr,
&dev_attr_temp2_crit_hyst.attr,
&dev_attr_alarms.attr,
&sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
&sensor_dev_attr_temp2_fault.dev_attr.attr,
&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
NULL
};
static const struct attribute_group max1619_group = {
.attrs = max1619_attributes,
};
/*
* Real code
*/
/* Return 0 if detection is successful, -ENODEV otherwise */
static int max1619_detect(struct i2c_client *client,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = client->adapter;
u8 reg_config, reg_convrate, reg_status, man_id, chip_id;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
/* detection */
reg_config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
reg_convrate = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONVRATE);
reg_status = i2c_smbus_read_byte_data(client, MAX1619_REG_R_STATUS);
if ((reg_config & 0x03) != 0x00
|| reg_convrate > 0x07 || (reg_status & 0x61) != 0x00) {
dev_dbg(&adapter->dev, "MAX1619 detection failed at 0x%02x\n",
client->addr);
return -ENODEV;
}
/* identification */
man_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_MAN_ID);
chip_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CHIP_ID);
if (man_id != 0x4D || chip_id != 0x04) {
dev_info(&adapter->dev,
"Unsupported chip (man_id=0x%02X, chip_id=0x%02X).\n",
man_id, chip_id);
return -ENODEV;
}
strlcpy(info->type, "max1619", I2C_NAME_SIZE);
return 0;
}
static int max1619_probe(struct i2c_client *new_client,
const struct i2c_device_id *id)
{
struct max1619_data *data;
int err;
data = devm_kzalloc(&new_client->dev, sizeof(struct max1619_data),
GFP_KERNEL);
if (!data)
return -ENOMEM;
i2c_set_clientdata(new_client, data);
data->valid = 0;
mutex_init(&data->update_lock);
/* Initialize the MAX1619 chip */
max1619_init_client(new_client);
/* Register sysfs hooks */
err = sysfs_create_group(&new_client->dev.kobj, &max1619_group);
if (err)
return err;
data->hwmon_dev = hwmon_device_register(&new_client->dev);
if (IS_ERR(data->hwmon_dev)) {
err = PTR_ERR(data->hwmon_dev);
goto exit_remove_files;
}
return 0;
exit_remove_files:
sysfs_remove_group(&new_client->dev.kobj, &max1619_group);
return err;
}
static void max1619_init_client(struct i2c_client *client)
{
u8 config;
/*
* Start the conversions.
*/
i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONVRATE,
5); /* 2 Hz */
config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
if (config & 0x40)
i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONFIG,
config & 0xBF); /* run */
}
static int max1619_remove(struct i2c_client *client)
{
struct max1619_data *data = i2c_get_clientdata(client);
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&client->dev.kobj, &max1619_group);
return 0;
}
static struct max1619_data *max1619_update_device(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct max1619_data *data = i2c_get_clientdata(client);
mutex_lock(&data->update_lock);
if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
dev_dbg(&client->dev, "Updating max1619 data.\n");
data->temp_input1 = i2c_smbus_read_byte_data(client,
MAX1619_REG_R_LOCAL_TEMP);
data->temp_input2 = i2c_smbus_read_byte_data(client,
MAX1619_REG_R_REMOTE_TEMP);
data->temp_high2 = i2c_smbus_read_byte_data(client,
MAX1619_REG_R_REMOTE_HIGH);
data->temp_low2 = i2c_smbus_read_byte_data(client,
MAX1619_REG_R_REMOTE_LOW);
data->temp_crit2 = i2c_smbus_read_byte_data(client,
MAX1619_REG_R_REMOTE_CRIT);
data->temp_hyst2 = i2c_smbus_read_byte_data(client,
MAX1619_REG_R_TCRIT_HYST);
data->alarms = i2c_smbus_read_byte_data(client,
MAX1619_REG_R_STATUS);
data->last_updated = jiffies;
data->valid = 1;
}
mutex_unlock(&data->update_lock);
return data;
}
module_i2c_driver(max1619_driver);
MODULE_AUTHOR("Oleksij Rempel <bug-track@fisher-privat.net> and "
"Jean Delvare <khali@linux-fr.org>");
MODULE_DESCRIPTION("MAX1619 sensor driver");
MODULE_LICENSE("GPL");
![swh spinner](/static/img/swh-spinner.gif)
Computing file changes ...