Re: [PATCH v2] hwmon: LM95245 driver

Guenter Roeck
2011-06-27T20:23:34Z

Hi Alexander,

On Mon, Jun 27, 2011 at 11:49:09AM -0400, Alexander Stein wrote:
> An hwmon driver for the National Semiconductor LM95245 dual temperature
> sensors chip.
>
> Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>

Now for a real review ...

Please make sure the driver does not generate any checkpatch errors or warnings.

> ---
> Changes in v2:
> * The diode mode isn't overwritten upon probe
> * Added crit, crit_hyst, alarm, fault
> * Added i2c address 0x29
>
> I didn't change the signed/unsigned part. I also didn't include offset support.
> Strangely enough the alarmfor remote (temp2) is set everytime I tested it,
> where temp is at +47.4 C and crit is 110 C with hyst at 10 C. I don't have any
> explanation for that.
>
Bug in your code - see below.

> drivers/hwmon/Kconfig | 9 +
> drivers/hwmon/Makefile | 1 +
> drivers/hwmon/lm95245.c | 532 +++++++++++++++++++++++++++++++++++++++++++++++

Please provide Documentation/hwmon/lm95245.

> 3 files changed, 542 insertions(+), 0 deletions(-)
> create mode 100644 drivers/hwmon/lm95245.c
>
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index 16db83c..4c2400b 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -702,6 +702,15 @@ config SENSORS_LM95241
> This driver can also be built as a module. If so, the module
> will be called lm95241.
>
> +config SENSORS_LM95245
> + tristate "National Semiconductor LM95245 sensor chip"
> + depends on I2C

&& EXPERIMENTAL

> + help
> + If you say yes here you get support for LM95245 sensor chip.
> +
> + This driver can also be built as a module. If so, the module
> + will be called lm95245.
> +
> config SENSORS_MAX1111
> tristate "Maxim MAX1111 Multichannel, Serial 8-bit ADC chip"
> depends on SPI_MASTER
> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
> index 28061cf..5598712 100644
> --- a/drivers/hwmon/Makefile
> +++ b/drivers/hwmon/Makefile
> @@ -80,6 +80,7 @@ obj-$(CONFIG_SENSORS_LM90) += lm90.o
> obj-$(CONFIG_SENSORS_LM92) += lm92.o
> obj-$(CONFIG_SENSORS_LM93) += lm93.o
> obj-$(CONFIG_SENSORS_LM95241) += lm95241.o
> +obj-$(CONFIG_SENSORS_LM95245) += lm95245.o
> obj-$(CONFIG_SENSORS_LTC4151) += ltc4151.o
> obj-$(CONFIG_SENSORS_LTC4215) += ltc4215.o
> obj-$(CONFIG_SENSORS_LTC4245) += ltc4245.o
> diff --git a/drivers/hwmon/lm95245.c b/drivers/hwmon/lm95245.c
> new file mode 100644
> index 0000000..1d93086
> --- /dev/null
> +++ b/drivers/hwmon/lm95245.c
> @@ -0,0 +1,532 @@
> +/*
> + * Copyright (C) 2011 Alexander Stein <alexander.stein@systec-electronic.com>
> + *
> + * The LM95245 is a sensor chip made by National Semiconductors.
> + * It reports up to two temperatures (its own plus an external one).
> + * Complete datasheet can be obtained from National's website at:
> + * http://www.national.com/ds.cgi/LM/LM95245.pdf
> + *
> + * This driver is based on lm95241.c
> + *
> + * 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>
> +
> +#define DEVNAME "lm95245"
> +
> +static const unsigned short normal_i2c[] = {
> + 0x18, 0x19, 0x29, 0x4c, 0x4d, I2C_CLIENT_END };
> +
> +/* LM95245 registers */
> +/* general registers */
> +#define LM95245_REG_RW_CONFIG1 0x03
> +#define LM95245_REG_RW_CONVERS_RATE 0x04
> +#define LM95245_REG_W_ONE_SHOT 0x0F
> +
> +/* diode configuration */
> +#define LM95245_REG_RW_CONFIG2 0xBF
> +#define LM95245_REG_RW_REMOTE_OFFH 0x11
> +#define LM95245_REG_RW_REMOTE_OFFL 0x12
> +
> +/* status registers */
> +#define LM95245_REG_R_STATUS1 0x02
> +#define LM95245_REG_R_STATUS2 0x33
> +
> +/* limit registers */
> +#define LM95245_REG_RW_REMOTE_OS_LIMIT 0x07
> +#define LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT 0x20
> +#define LM95245_REG_RW_REMOTE_TCRIT_LIMIT 0x19
> +#define LM95245_REG_RW_COMMON_HYSTERESIS 0x21
> +
> +/* temperature signed */
> +#define LM95245_REG_R_LOCAL_TEMPH_S 0x00
> +#define LM95245_REG_R_LOCAL_TEMPL_S 0x30
> +#define LM95245_REG_R_REMOTE_TEMPH_S 0x01
> +#define LM95245_REG_R_REMOTE_TEMPL_S 0x10
> +/* temperature unsigned */
> +#define LM95245_REG_R_REMOTE_TEMPH_U 0x31
> +#define LM95245_REG_R_REMOTE_TEMPL_U 0x32
> +
> +/* id registers */
> +#define LM95245_REG_R_MAN_ID 0xFE
> +#define LM95245_REG_R_CHIP_ID 0xFF
> +
> +/* LM95245 specific bitfields */
> +#define CFG_STOP 0x40
> +#define CFG_REMOTE_TCRIT_MASK 0x10
> +#define CFG_REMOTE_OS_MASK 0x08
> +#define CFG_LOCAL_TCRIT_MASK 0x04
> +#define CFG_LOCAL_OS_MASK 0x02
> +
> +#define CFG2_OS_A0 0x40
> +#define CFG2_DIODE_FAULT_OS 0x20
> +#define CFG2_DIODE_FAULT_TCRIT 0x10
> +#define CFG2_REMOTE_TT 0x08
> +#define CFG2_REMOTE_FILTER_DIS 0x00
> +#define CFG2_REMOTE_FILTER_EN 0x06
> +
> +/* conversation rate in ms */
> +#define RATE_CR0063 0x00
> +#define RATE_CR0364 0x01
> +#define RATE_CR1000 0x02
> +#define RATE_CR2500 0x03
> +
Please use tabs for alignment.

> +#define STATUS1_BUSY 0x80
> +#define STATUS1_ROS 0x10

Unless you plan to use the above OS and BUSY related defines, might as well drop it.

Would it make sense to support the "OS" limits, possibly as "max" limits ?

I don't really understand the logic in the datasheet, though,
since the OS limits seem to be intended for "shutdown", yet
the "critical" limit is higher by default.

> +#define STATUS1_DIODE_FAULT 0x04
> +#define STATUS1_RTCRIT 0x02
> +#define STATUS1_LOC 0x01
> +
> +#define MANUFACTURER_ID 0x01
> +#define DEFAULT_REVISION 0xB3
> +
Please use tabs for alignment.

> +static const u8 lm95245_reg_address[] = {
> + LM95245_REG_R_LOCAL_TEMPH_S,
> + LM95245_REG_R_LOCAL_TEMPL_S,
> + LM95245_REG_R_REMOTE_TEMPH_S,
> + LM95245_REG_R_REMOTE_TEMPL_S,
> + LM95245_REG_R_REMOTE_TEMPH_U,
> + LM95245_REG_R_REMOTE_TEMPL_U,
> + LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT,
> + LM95245_REG_RW_REMOTE_TCRIT_LIMIT,
> + LM95245_REG_RW_COMMON_HYSTERESIS,
> + LM95245_REG_R_STATUS1,
> +};
> +
> +/* Client data (each client gets its own) */
> +struct lm95245_data {
> + struct device *hwmon_dev;
> + struct mutex update_lock;
> + unsigned long last_updated; /* in jiffies */
> + unsigned long interval; /* in msecs */
> + char valid; /* zero until following fields are valid */
> + /* registers values */
> + u8 temp[ARRAY_SIZE(lm95245_reg_address)];

A better name for the array might be regs[] or similar, since you use it
for values other than temperatures.

> + u8 config1, config2;
> +};
> +
> +/* Conversions */
> +static int TempFromRegUnsigned(u8 val_h, u8 val_l)
> +{
> + return val_h * 1000 + val_l * 1000 / 256;
> +}
> +
> +static int TempFromRegSigned(u8 val_h, u8 val_l)
> +{
> + if (val_h & 0x80)
> + return val_h - 0x100;

Should this be (val_h - 0x100) * 1000 ?

> + return TempFromRegUnsigned(val_h, val_l);
> +}
> +
> +static struct lm95245_data *lm95245_update_device(struct device *dev)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + struct lm95245_data *data = i2c_get_clientdata(client);
> +
> + mutex_lock(&data->update_lock);
> +
> + if (time_after(jiffies, data->last_updated + msecs_to_jiffies(data->interval)) ||
> + !data->valid) {
> + int i;
> +
> + dev_dbg(&client->dev, "Updating lm95245 data.\n");
> + for (i = 0; i < ARRAY_SIZE(lm95245_reg_address); i++)
> + data->temp[i]
> + = i2c_smbus_read_byte_data(client,
> + lm95245_reg_address[i]);
> + data->last_updated = jiffies;
> + data->valid = 1;
> + }
> +
> + mutex_unlock(&data->update_lock);
> +
> + return data;
> +}
> +
> +static unsigned long lm95245_set_conversation_rate(struct i2c_client *client, unsigned long interval)
> +{

Longer than 80 columns (for which you get a checkpatch warning),
and maybe consider renaming the function to lm95245_set_conversion_rate ?

> + int rate;
> +
> + if (interval < 63) {
> + interval = 63;
> + rate = RATE_CR0063;
> + } else if (interval < 364) {
> + interval = 364;
> + rate = RATE_CR0364;
> + } else if (interval < 1000) {
> + interval = 1000;
> + rate = RATE_CR1000;
> + } else {
> + interval = 2500;
> + rate = RATE_CR2500;
> + }
> +
> + i2c_smbus_write_byte_data(client, LM95245_REG_RW_CONVERS_RATE, rate);
> +
> + return interval;
> +}
> +
> +/* Sysfs stuff */
> +static ssize_t show_input(struct device *dev, struct device_attribute *attr,
> + char *buf)
> +{
> + struct lm95245_data *data = lm95245_update_device(dev);
> + int temp;
> + int index = to_sensor_dev_attr(attr)->index;
> +
> + /*
> + * Index 0 (Local temp) is always signed
> + * Index 2 (Remote temp) has both signed and unsigned data
> + * use signed calculation for remote if signed bit is set
> + */
> + if (index == 0 || data->temp[index] & 0x80)
> + temp = TempFromRegSigned(data->temp[index],
> + data->temp[index + 1]);
> + else
> + temp = TempFromRegUnsigned(data->temp[index + 2],
> + data->temp[index + 3]);
> +
> + return snprintf(buf, PAGE_SIZE - 1, "%d\n", temp);
> +}
> +
> +static ssize_t show_crit(struct device *dev, struct device_attribute *attr,
> + char *buf)
> +{
> + struct lm95245_data *data = lm95245_update_device(dev);
> + int index = to_sensor_dev_attr(attr)->index;
> + int crit;
> +
> + crit = TempFromRegUnsigned(data->temp[index], 0);
> +
> + return snprintf(buf, PAGE_SIZE - 1, "%d\n", crit);

return snprintf(buf, PAGE_SIZE - 1, "%d\n",
data->temp[index] * 1000);

would be less complex and accomplish the same.

> +}

Empty line between functions, please.

> +static ssize_t set_crit(struct device *dev, struct device_attribute *attr,
> + const char *buf, size_t count)
> +{

set_limit and show_limit might be better names here, since you use the functions for
more than "crit" temperatures.

> + struct i2c_client *client = to_i2c_client(dev);
> + struct lm95245_data *data = i2c_get_clientdata(client);
> + int index = to_sensor_dev_attr(attr)->index;
> + unsigned long val;
> +
> + if (strict_strtoul(buf, 10, &val) < 0)
> + return -EINVAL;
> +
> + val /= 1000;
> +
> + val = SENSORS_LIMIT(val, 0, (index == 6 ? 127 : 256));
> +
256 -> 255

> + mutex_lock(&data->update_lock);
> +
> + data->valid = 0;
> +
> + if (index == 6)
> + /* local crit */
> + i2c_smbus_write_byte_data(client,
> + LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT, val);
> + else if (index == 7)
> + /* remote crit */
> + i2c_smbus_write_byte_data(client,
> + LM95245_REG_RW_REMOTE_TCRIT_LIMIT, val);
> + else
> + return -EINVAL;
> +
You can simplify this code to
i2c_smbus_write_byte_data(client, lm95245_reg_address[index], val);

> + mutex_unlock(&data->update_lock);
> +
> + return count;
> +}

Empty line between functions, please.

> +static ssize_t set_crit_hyst(struct device *dev, struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + struct lm95245_data *data = i2c_get_clientdata(client);
> + unsigned long val;
> +
> + if (strict_strtoul(buf, 10, &val) < 0)
> + return -EINVAL;
> +
> + val /= 1000;
> +
> + val = SENSORS_LIMIT(val, 0, 31);
> +
> + mutex_lock(&data->update_lock);
> +
> + data->valid = 0;
> +
> + /* shared crit hysteresis */
> + i2c_smbus_write_byte_data(client, LM95245_REG_RW_COMMON_HYSTERESIS, val);
> +
> + mutex_unlock(&data->update_lock);
> +
> + return count;
> +}
> +
> +static ssize_t show_type(struct device *dev, struct device_attribute *attr,
> + char *buf)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + struct lm95245_data *data = i2c_get_clientdata(client);
> +
> + return snprintf(buf, PAGE_SIZE - 1,
> + data->config2 & CFG2_REMOTE_TT ? "1\n" : "2\n");
> +}

Empty line between functions, please.

> +static ssize_t set_type(struct device *dev, struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + struct lm95245_data *data = i2c_get_clientdata(client);
> + unsigned long val;
> +
> + if (strict_strtoul(buf, 10, &val) < 0)
> + return -EINVAL;
> + if (val != 1 && val != 2)
> + return -EINVAL;
> +
> + mutex_lock(&data->update_lock);
> +
> + if (val == 1)
> + data->config2 |= CFG2_REMOTE_TT;
> + else
> + data->config2 &= ~CFG2_REMOTE_TT;
> +
> + data->valid = 0;
> +
> + i2c_smbus_write_byte_data(client, LM95245_REG_RW_CONFIG2,
> + data->config2);
> +
> + mutex_unlock(&data->update_lock);
> +
> + return count;
> +}
> +
> +static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
> + char *buf)
> +{
> + struct lm95245_data *data = lm95245_update_device(dev);
> + int index = to_sensor_dev_attr(attr)->index;
> + bool alarm;
> +
> + mutex_lock(&data->update_lock);
> +
> + alarm = lm95245_reg_address[9] & index;
> +

That may explain your problem with the always-on alarm... you are using
the register address, not the register value. You might want to try
alarm = data->temp[9] & index;
for better results.

> + mutex_unlock(&data->update_lock);
> +
> + return snprintf(buf, PAGE_SIZE - 1, "%d\n", !!alarm);

Locks are not needed here. Also,

return snprintf(buf, PAGE_SIZE - 1, "%d\n",
!!(data->temp[9] & index));

would accomplish the same.

If you want to keep the alarm variable, you don't need !!alarm,
since the assignment to bool alarm already converts the numeric value to {0, 1}.

> +}
> +
> +static ssize_t show_interval(struct device *dev, struct device_attribute *attr,
> + char *buf)
> +{
> + struct lm95245_data *data = lm95245_update_device(dev);
> +
> + return snprintf(buf, PAGE_SIZE - 1, "%lu\n", data->interval);
> +}
> +
> +static ssize_t set_interval(struct device *dev, struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + struct lm95245_data *data = i2c_get_clientdata(client);
> + unsigned long val;
> +
> + if (strict_strtoul(buf, 10, &val) < 0)
> + return -EINVAL;
> +
> + mutex_lock(&data->update_lock);
> +
> + data->interval = lm95245_set_conversation_rate(client, val);
> +
> + mutex_unlock(&data->update_lock);
> +
> + return count;
> +}
> +
> +static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_input, NULL, 0);
> +static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_crit, set_crit, 6);
> +static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, show_crit,
> + set_crit_hyst, 8);
> +static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, show_alarm, NULL, STATUS1_LOC);
> +
This should be temp1_crit_alarm, since you use "crit" for the limits as well.

> +static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_input, NULL, 2);
> +static SENSOR_DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_crit, set_crit, 7);
> +static SENSOR_DEVICE_ATTR(temp2_crit_hyst, S_IWUSR | S_IRUGO, show_crit,
> + set_crit_hyst, 8);
> +static SENSOR_DEVICE_ATTR(temp2_type, S_IWUSR | S_IRUGO, show_type,
> + set_type, 0);
> +static SENSOR_DEVICE_ATTR(temp2_alarm, S_IRUGO, show_alarm, NULL, STATUS1_RTCRIT);

temp2_crit_alarm

> +static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, STATUS1_DIODE_FAULT);
> +
> +static DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO, show_interval,
> + set_interval);
> +
> +static struct attribute *lm95245_attributes[] = {
> + &sensor_dev_attr_temp1_input.dev_attr.attr,
> + &sensor_dev_attr_temp1_crit.dev_attr.attr,
> + &sensor_dev_attr_temp1_crit_hyst.dev_attr.attr,
> + &sensor_dev_attr_temp1_alarm.dev_attr.attr,
> + &sensor_dev_attr_temp2_input.dev_attr.attr,
> + &sensor_dev_attr_temp2_crit.dev_attr.attr,
> + &sensor_dev_attr_temp2_crit_hyst.dev_attr.attr,
> + &sensor_dev_attr_temp2_type.dev_attr.attr,
> + &sensor_dev_attr_temp2_alarm.dev_attr.attr,
> + &sensor_dev_attr_temp2_fault.dev_attr.attr,
> + &dev_attr_update_interval.attr,
> + NULL
> +};
> +
> +static const struct attribute_group lm95245_group = {
> + .attrs = lm95245_attributes,
> +};
> +
> +/* Return 0 if detection is successful, -ENODEV otherwise */
> +static int lm95245_detect(struct i2c_client *new_client,
> + struct i2c_board_info *info)
> +{
> + struct i2c_adapter *adapter = new_client->adapter;
> + int address = new_client->addr;
> + const char *name;
> +
> + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
> + return -ENODEV;
> +
> + if ((i2c_smbus_read_byte_data(new_client, LM95245_REG_R_MAN_ID)
> + == MANUFACTURER_ID)
> + && (i2c_smbus_read_byte_data(new_client, LM95245_REG_R_CHIP_ID)
> + >= DEFAULT_REVISION)) {

This should be ==. We'll also have to change that for the LM95241 driver,
which accepts the LM95245 since it uses >= as well. Also, there is an unnecessary
set of ().

> + name = DEVNAME;
> + } else {
> + dev_dbg(&adapter->dev, "LM95245 detection failed at 0x%02x\n",
> + address);

There should be no message here, even debugging. Otherwise there is lot of
debugging noise for each supported address (and each chip failing to be detected
on it). Again something to change for the LM95241 driver.

Also,
if (i2c_smbus_read_byte_data(new_client, LM95245_REG_R_MAN_ID)
!= MANUFACTURER_ID
|| i2c_smbus_read_byte_data(new_client, LM95245_REG_R_CHIP_ID)
!= DEFAULT_REVISION) {
return -ENODEV;

strlcpy(info->type, DEVNAME, I2C_NAME_SIZE);

would be much simpler.

> + return -ENODEV;
> + }
> +
> + /* Fill the i2c board info */

This comment does not really provide any value.

> + strlcpy(info->type, name, I2C_NAME_SIZE);
> + return 0;
> +}
> +
> +static void lm95245_init_client(struct i2c_client *client)
> +{
> + struct lm95245_data *data = i2c_get_clientdata(client);
> +
> + data->interval = 1000; /* 1 sec default */
> + data->valid = 0;
> + data->config1 = 0;
> +
config1 defaults to 0 after poweron, so if it is different this was
set on purpose by BIOS/ROMMON. I don't think you should override that,
except for clearing bit 6 to enable the chip if it was disabled.

> + data->config2 = i2c_smbus_read_byte_data(client, data->config2);
> +
> + /* Do not set diode model in ervery case */
> + data->config2 |= CFG2_DIODE_FAULT_TCRIT | CFG2_REMOTE_FILTER_EN;
> +

Both bit masks are already set after chip reset, so if they are disabled it
was done on purpose by the BIOS/ROMMON. I don't think you should override that.

> + i2c_smbus_write_byte_data(client, LM95245_REG_RW_CONFIG1, data->config1);
> + i2c_smbus_write_byte_data(client, LM95245_REG_RW_CONFIG2, data->config2);
> + lm95245_set_conversation_rate(client, data->interval);
> +}
> +
> +static int lm95245_probe(struct i2c_client *new_client,
> + const struct i2c_device_id *id)
> +{
> + struct lm95245_data *data;
> + int err;
> +
> + data = kzalloc(sizeof(struct lm95245_data), GFP_KERNEL);
> + if (!data) {
> + err = -ENOMEM;
> + goto exit;
> + }
> +
> + i2c_set_clientdata(new_client, data);
> + mutex_init(&data->update_lock);
> +
> + /* Initialize the LM95245 chip */
> + lm95245_init_client(new_client);
> +
> + /* Register sysfs hooks */
> + err = sysfs_create_group(&new_client->dev.kobj, &lm95245_group);
> + if (err)
> + goto exit_free;
> +
> + 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, &lm95245_group);
> +exit_free:
> + kfree(data);
> +exit:
> + return err;
> +}
> +
> +static int lm95245_remove(struct i2c_client *client)
> +{
> + struct lm95245_data *data = i2c_get_clientdata(client);
> +
> + hwmon_device_unregister(data->hwmon_dev);
> + sysfs_remove_group(&client->dev.kobj, &lm95245_group);
> +
> + kfree(data);
> + return 0;
> +}
> +
> +/* Driver data (common to all clients) */
> +static const struct i2c_device_id lm95245_id[] = {
> + { DEVNAME, 0 },
> + { }
> +};
> +MODULE_DEVICE_TABLE(i2c, lm95245_id);
> +
> +static struct i2c_driver lm95245_driver = {
> + .class = I2C_CLASS_HWMON,
> + .driver = {
> + .name = DEVNAME,
> + },
> + .probe = lm95245_probe,
> + .remove = lm95245_remove,
> + .id_table = lm95245_id,
> + .detect = lm95245_detect,
> + .address_list = normal_i2c,
> +};
> +
> +static int __init sensors_lm95245_init(void)
> +{
> + return i2c_add_driver(&lm95245_driver);
> +}
> +
> +static void __exit sensors_lm95245_exit(void)
> +{
> + i2c_del_driver(&lm95245_driver);
> +}
> +
> +MODULE_AUTHOR("Alexander Stein <alexander.stein@systec-electronic.com>");
> +MODULE_DESCRIPTION("LM95245 sensor driver");
> +MODULE_LICENSE("GPL");
> +
> +module_init(sensors_lm95245_init);
> +module_exit(sensors_lm95245_exit);
> --
> 1.7.3.4
>