linuxdebug/drivers/hwmon/adm9240.c

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2024-07-16 15:50:57 +02:00
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* adm9240.c Part of lm_sensors, Linux kernel modules for hardware
* monitoring
*
* Copyright (C) 1999 Frodo Looijaard <frodol@dds.nl>
* Philip Edelbrock <phil@netroedge.com>
* Copyright (C) 2003 Michiel Rook <michiel@grendelproject.nl>
* Copyright (C) 2005 Grant Coady <gcoady.lk@gmail.com> with valuable
* guidance from Jean Delvare
*
* Driver supports Analog Devices ADM9240
* Dallas Semiconductor DS1780
* National Semiconductor LM81
*
* ADM9240 is the reference, DS1780 and LM81 are register compatibles
*
* Voltage Six inputs are scaled by chip, VID also reported
* Temperature Chip temperature to 0.5'C, maximum and max_hysteris
* Fans 2 fans, low speed alarm, automatic fan clock divider
* Alarms 16-bit map of active alarms
* Analog Out 0..1250 mV output
*
* Chassis Intrusion: clear CI latch with 'echo 0 > intrusion0_alarm'
*
* Test hardware: Intel SE440BX-2 desktop motherboard --Grant
*
* LM81 extended temp reading not implemented
*/
#include <linux/bits.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/hwmon-sysfs.h>
#include <linux/hwmon.h>
#include <linux/hwmon-vid.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/regmap.h>
/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x2c, 0x2d, 0x2e, 0x2f,
I2C_CLIENT_END };
enum chips { adm9240, ds1780, lm81 };
/* ADM9240 registers */
#define ADM9240_REG_MAN_ID 0x3e
#define ADM9240_REG_DIE_REV 0x3f
#define ADM9240_REG_CONFIG 0x40
#define ADM9240_REG_IN(nr) (0x20 + (nr)) /* 0..5 */
#define ADM9240_REG_IN_MAX(nr) (0x2b + (nr) * 2)
#define ADM9240_REG_IN_MIN(nr) (0x2c + (nr) * 2)
#define ADM9240_REG_FAN(nr) (0x28 + (nr)) /* 0..1 */
#define ADM9240_REG_FAN_MIN(nr) (0x3b + (nr))
#define ADM9240_REG_INT(nr) (0x41 + (nr))
#define ADM9240_REG_INT_MASK(nr) (0x43 + (nr))
#define ADM9240_REG_TEMP 0x27
#define ADM9240_REG_TEMP_MAX(nr) (0x39 + (nr)) /* 0, 1 = high, hyst */
#define ADM9240_REG_ANALOG_OUT 0x19
#define ADM9240_REG_CHASSIS_CLEAR 0x46
#define ADM9240_REG_VID_FAN_DIV 0x47
#define ADM9240_REG_I2C_ADDR 0x48
#define ADM9240_REG_VID4 0x49
#define ADM9240_REG_TEMP_CONF 0x4b
/* generalised scaling with integer rounding */
static inline int SCALE(long val, int mul, int div)
{
if (val < 0)
return (val * mul - div / 2) / div;
else
return (val * mul + div / 2) / div;
}
/* adm9240 internally scales voltage measurements */
static const u16 nom_mv[] = { 2500, 2700, 3300, 5000, 12000, 2700 };
static inline unsigned int IN_FROM_REG(u8 reg, int n)
{
return SCALE(reg, nom_mv[n], 192);
}
static inline u8 IN_TO_REG(unsigned long val, int n)
{
val = clamp_val(val, 0, nom_mv[n] * 255 / 192);
return SCALE(val, 192, nom_mv[n]);
}
/* temperature range: -40..125, 127 disables temperature alarm */
static inline s8 TEMP_TO_REG(long val)
{
val = clamp_val(val, -40000, 127000);
return SCALE(val, 1, 1000);
}
/* two fans, each with low fan speed limit */
static inline unsigned int FAN_FROM_REG(u8 reg, u8 div)
{
if (!reg) /* error */
return -1;
if (reg == 255)
return 0;
return SCALE(1350000, 1, reg * div);
}
/* analog out 0..1250mV */
static inline u8 AOUT_TO_REG(unsigned long val)
{
val = clamp_val(val, 0, 1250);
return SCALE(val, 255, 1250);
}
static inline unsigned int AOUT_FROM_REG(u8 reg)
{
return SCALE(reg, 1250, 255);
}
/* per client data */
struct adm9240_data {
struct device *dev;
struct regmap *regmap;
struct mutex update_lock;
u8 fan_div[2]; /* rw fan1_div, read-only accessor */
u8 vrm; /* -- vrm set on startup, no accessor */
};
/* write new fan div, callers must hold data->update_lock */
static int adm9240_write_fan_div(struct adm9240_data *data, int channel, u8 fan_div)
{
unsigned int reg, old, shift = (channel + 2) * 2;
int err;
err = regmap_read(data->regmap, ADM9240_REG_VID_FAN_DIV, &reg);
if (err < 0)
return err;
old = (reg >> shift) & 3;
reg &= ~(3 << shift);
reg |= (fan_div << shift);
err = regmap_write(data->regmap, ADM9240_REG_VID_FAN_DIV, reg);
if (err < 0)
return err;
dev_dbg(data->dev,
"fan%d clock divider changed from %lu to %lu\n",
channel + 1, BIT(old), BIT(fan_div));
return 0;
}
/*
* set fan speed low limit:
*
* - value is zero: disable fan speed low limit alarm
*
* - value is below fan speed measurement range: enable fan speed low
* limit alarm to be asserted while fan speed too slow to measure
*
* - otherwise: select fan clock divider to suit fan speed low limit,
* measurement code may adjust registers to ensure fan speed reading
*/
static int adm9240_fan_min_write(struct adm9240_data *data, int channel, long val)
{
u8 new_div;
u8 fan_min;
int err;
mutex_lock(&data->update_lock);
if (!val) {
fan_min = 255;
new_div = data->fan_div[channel];
dev_dbg(data->dev, "fan%u low limit set disabled\n", channel + 1);
} else if (val < 1350000 / (8 * 254)) {
new_div = 3;
fan_min = 254;
dev_dbg(data->dev, "fan%u low limit set minimum %u\n",
channel + 1, FAN_FROM_REG(254, BIT(new_div)));
} else {
unsigned int new_min = 1350000 / val;
new_div = 0;
while (new_min > 192 && new_div < 3) {
new_div++;
new_min /= 2;
}
if (!new_min) /* keep > 0 */
new_min++;
fan_min = new_min;
dev_dbg(data->dev, "fan%u low limit set fan speed %u\n",
channel + 1, FAN_FROM_REG(new_min, BIT(new_div)));
}
if (new_div != data->fan_div[channel]) {
data->fan_div[channel] = new_div;
adm9240_write_fan_div(data, channel, new_div);
}
err = regmap_write(data->regmap, ADM9240_REG_FAN_MIN(channel), fan_min);
mutex_unlock(&data->update_lock);
return err;
}
static ssize_t cpu0_vid_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct adm9240_data *data = dev_get_drvdata(dev);
unsigned int regval;
int err;
u8 vid;
err = regmap_read(data->regmap, ADM9240_REG_VID_FAN_DIV, &regval);
if (err < 0)
return err;
vid = regval & 0x0f;
err = regmap_read(data->regmap, ADM9240_REG_VID4, &regval);
if (err < 0)
return err;
vid |= (regval & 1) << 4;
return sprintf(buf, "%d\n", vid_from_reg(vid, data->vrm));
}
static DEVICE_ATTR_RO(cpu0_vid);
static ssize_t aout_output_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct adm9240_data *data = dev_get_drvdata(dev);
unsigned int regval;
int err;
err = regmap_read(data->regmap, ADM9240_REG_ANALOG_OUT, &regval);
if (err)
return err;
return sprintf(buf, "%d\n", AOUT_FROM_REG(regval));
}
static ssize_t aout_output_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct adm9240_data *data = dev_get_drvdata(dev);
long val;
int err;
err = kstrtol(buf, 10, &val);
if (err)
return err;
err = regmap_write(data->regmap, ADM9240_REG_ANALOG_OUT, AOUT_TO_REG(val));
return err < 0 ? err : count;
}
static DEVICE_ATTR_RW(aout_output);
static struct attribute *adm9240_attrs[] = {
&dev_attr_aout_output.attr,
&dev_attr_cpu0_vid.attr,
NULL
};
ATTRIBUTE_GROUPS(adm9240);
/*** sensor chip detect and driver install ***/
/* Return 0 if detection is successful, -ENODEV otherwise */
static int adm9240_detect(struct i2c_client *new_client,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = new_client->adapter;
const char *name = "";
int address = new_client->addr;
u8 man_id, die_rev;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
/* verify chip: reg address should match i2c address */
if (i2c_smbus_read_byte_data(new_client, ADM9240_REG_I2C_ADDR) != address)
return -ENODEV;
/* check known chip manufacturer */
man_id = i2c_smbus_read_byte_data(new_client, ADM9240_REG_MAN_ID);
if (man_id == 0x23)
name = "adm9240";
else if (man_id == 0xda)
name = "ds1780";
else if (man_id == 0x01)
name = "lm81";
else
return -ENODEV;
/* successful detect, print chip info */
die_rev = i2c_smbus_read_byte_data(new_client, ADM9240_REG_DIE_REV);
dev_info(&adapter->dev, "found %s revision %u\n",
man_id == 0x23 ? "ADM9240" :
man_id == 0xda ? "DS1780" : "LM81", die_rev);
strscpy(info->type, name, I2C_NAME_SIZE);
return 0;
}
static int adm9240_init_client(struct adm9240_data *data)
{
unsigned int regval;
u8 conf, mode;
int err;
err = regmap_raw_read(data->regmap, ADM9240_REG_CONFIG, &conf, 1);
if (err < 0)
return err;
err = regmap_raw_read(data->regmap, ADM9240_REG_TEMP_CONF, &mode, 1);
if (err < 0)
return err;
mode &= 3;
data->vrm = vid_which_vrm(); /* need this to report vid as mV */
dev_info(data->dev, "Using VRM: %d.%d\n", data->vrm / 10,
data->vrm % 10);
if (conf & 1) { /* measurement cycle running: report state */
dev_info(data->dev, "status: config 0x%02x mode %u\n",
conf, mode);
} else { /* cold start: open limits before starting chip */
int i;
for (i = 0; i < 6; i++) {
err = regmap_write(data->regmap,
ADM9240_REG_IN_MIN(i), 0);
if (err < 0)
return err;
err = regmap_write(data->regmap,
ADM9240_REG_IN_MAX(i), 255);
if (err < 0)
return err;
}
for (i = 0; i < 2; i++) {
err = regmap_write(data->regmap,
ADM9240_REG_FAN_MIN(i), 255);
if (err < 0)
return err;
}
for (i = 0; i < 2; i++) {
err = regmap_write(data->regmap,
ADM9240_REG_TEMP_MAX(i), 127);
if (err < 0)
return err;
}
/* start measurement cycle */
err = regmap_write(data->regmap, ADM9240_REG_CONFIG, 1);
if (err < 0)
return err;
dev_info(data->dev,
"cold start: config was 0x%02x mode %u\n", conf, mode);
}
/* read fan divs */
err = regmap_read(data->regmap, ADM9240_REG_VID_FAN_DIV, &regval);
if (err < 0)
return err;
data->fan_div[0] = (regval >> 4) & 3;
data->fan_div[1] = (regval >> 6) & 3;
return 0;
}
static int adm9240_chip_read(struct device *dev, u32 attr, long *val)
{
struct adm9240_data *data = dev_get_drvdata(dev);
u8 regs[2];
int err;
switch (attr) {
case hwmon_chip_alarms:
err = regmap_bulk_read(data->regmap, ADM9240_REG_INT(0), &regs, 2);
if (err < 0)
return err;
*val = regs[0] | regs[1] << 8;
break;
default:
return -EOPNOTSUPP;
}
return 0;
}
static int adm9240_intrusion_read(struct device *dev, u32 attr, long *val)
{
struct adm9240_data *data = dev_get_drvdata(dev);
unsigned int regval;
int err;
switch (attr) {
case hwmon_intrusion_alarm:
err = regmap_read(data->regmap, ADM9240_REG_INT(1), &regval);
if (err < 0)
return err;
*val = !!(regval & BIT(4));
break;
default:
return -EOPNOTSUPP;
}
return 0;
}
static int adm9240_intrusion_write(struct device *dev, u32 attr, long val)
{
struct adm9240_data *data = dev_get_drvdata(dev);
int err;
switch (attr) {
case hwmon_intrusion_alarm:
if (val)
return -EINVAL;
err = regmap_write(data->regmap, ADM9240_REG_CHASSIS_CLEAR, 0x80);
if (err < 0)
return err;
dev_dbg(data->dev, "chassis intrusion latch cleared\n");
break;
default:
return -EOPNOTSUPP;
}
return 0;
}
static int adm9240_in_read(struct device *dev, u32 attr, int channel, long *val)
{
struct adm9240_data *data = dev_get_drvdata(dev);
unsigned int regval;
int reg;
int err;
switch (attr) {
case hwmon_in_input:
reg = ADM9240_REG_IN(channel);
break;
case hwmon_in_min:
reg = ADM9240_REG_IN_MIN(channel);
break;
case hwmon_in_max:
reg = ADM9240_REG_IN_MAX(channel);
break;
case hwmon_in_alarm:
if (channel < 4) {
reg = ADM9240_REG_INT(0);
} else {
reg = ADM9240_REG_INT(1);
channel -= 4;
}
err = regmap_read(data->regmap, reg, &regval);
if (err < 0)
return err;
*val = !!(regval & BIT(channel));
return 0;
default:
return -EOPNOTSUPP;
}
err = regmap_read(data->regmap, reg, &regval);
if (err < 0)
return err;
*val = IN_FROM_REG(regval, channel);
return 0;
}
static int adm9240_in_write(struct device *dev, u32 attr, int channel, long val)
{
struct adm9240_data *data = dev_get_drvdata(dev);
int reg;
switch (attr) {
case hwmon_in_min:
reg = ADM9240_REG_IN_MIN(channel);
break;
case hwmon_in_max:
reg = ADM9240_REG_IN_MAX(channel);
break;
default:
return -EOPNOTSUPP;
}
return regmap_write(data->regmap, reg, IN_TO_REG(val, channel));
}
static int adm9240_fan_read(struct device *dev, u32 attr, int channel, long *val)
{
struct adm9240_data *data = dev_get_drvdata(dev);
unsigned int regval;
int err;
switch (attr) {
case hwmon_fan_input:
mutex_lock(&data->update_lock);
err = regmap_read(data->regmap, ADM9240_REG_FAN(channel), &regval);
if (err < 0) {
mutex_unlock(&data->update_lock);
return err;
}
if (regval == 255 && data->fan_div[channel] < 3) {
/* adjust fan clock divider on overflow */
err = adm9240_write_fan_div(data, channel,
++data->fan_div[channel]);
if (err) {
mutex_unlock(&data->update_lock);
return err;
}
}
*val = FAN_FROM_REG(regval, BIT(data->fan_div[channel]));
mutex_unlock(&data->update_lock);
break;
case hwmon_fan_div:
*val = BIT(data->fan_div[channel]);
break;
case hwmon_fan_min:
err = regmap_read(data->regmap, ADM9240_REG_FAN_MIN(channel), &regval);
if (err < 0)
return err;
*val = FAN_FROM_REG(regval, BIT(data->fan_div[channel]));
break;
case hwmon_fan_alarm:
err = regmap_read(data->regmap, ADM9240_REG_INT(0), &regval);
if (err < 0)
return err;
*val = !!(regval & BIT(channel + 6));
break;
default:
return -EOPNOTSUPP;
}
return 0;
}
static int adm9240_fan_write(struct device *dev, u32 attr, int channel, long val)
{
struct adm9240_data *data = dev_get_drvdata(dev);
int err;
switch (attr) {
case hwmon_fan_min:
err = adm9240_fan_min_write(data, channel, val);
if (err < 0)
return err;
break;
default:
return -EOPNOTSUPP;
}
return 0;
}
static int adm9240_temp_read(struct device *dev, u32 attr, int channel, long *val)
{
struct adm9240_data *data = dev_get_drvdata(dev);
unsigned int regval;
int err, temp;
switch (attr) {
case hwmon_temp_input:
err = regmap_read(data->regmap, ADM9240_REG_TEMP, &regval);
if (err < 0)
return err;
temp = regval << 1;
err = regmap_read(data->regmap, ADM9240_REG_TEMP_CONF, &regval);
if (err < 0)
return err;
temp |= regval >> 7;
*val = sign_extend32(temp, 8) * 500;
break;
case hwmon_temp_max:
err = regmap_read(data->regmap, ADM9240_REG_TEMP_MAX(0), &regval);
if (err < 0)
return err;
*val = (s8)regval * 1000;
break;
case hwmon_temp_max_hyst:
err = regmap_read(data->regmap, ADM9240_REG_TEMP_MAX(1), &regval);
if (err < 0)
return err;
*val = (s8)regval * 1000;
break;
case hwmon_temp_alarm:
err = regmap_read(data->regmap, ADM9240_REG_INT(0), &regval);
if (err < 0)
return err;
*val = !!(regval & BIT(4));
break;
default:
return -EOPNOTSUPP;
}
return 0;
}
static int adm9240_temp_write(struct device *dev, u32 attr, int channel, long val)
{
struct adm9240_data *data = dev_get_drvdata(dev);
int reg;
switch (attr) {
case hwmon_temp_max:
reg = ADM9240_REG_TEMP_MAX(0);
break;
case hwmon_temp_max_hyst:
reg = ADM9240_REG_TEMP_MAX(1);
break;
default:
return -EOPNOTSUPP;
}
return regmap_write(data->regmap, reg, TEMP_TO_REG(val));
}
static int adm9240_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
int channel, long *val)
{
switch (type) {
case hwmon_chip:
return adm9240_chip_read(dev, attr, val);
case hwmon_intrusion:
return adm9240_intrusion_read(dev, attr, val);
case hwmon_in:
return adm9240_in_read(dev, attr, channel, val);
case hwmon_fan:
return adm9240_fan_read(dev, attr, channel, val);
case hwmon_temp:
return adm9240_temp_read(dev, attr, channel, val);
default:
return -EOPNOTSUPP;
}
}
static int adm9240_write(struct device *dev, enum hwmon_sensor_types type, u32 attr,
int channel, long val)
{
switch (type) {
case hwmon_intrusion:
return adm9240_intrusion_write(dev, attr, val);
case hwmon_in:
return adm9240_in_write(dev, attr, channel, val);
case hwmon_fan:
return adm9240_fan_write(dev, attr, channel, val);
case hwmon_temp:
return adm9240_temp_write(dev, attr, channel, val);
default:
return -EOPNOTSUPP;
}
}
static umode_t adm9240_is_visible(const void *_data, enum hwmon_sensor_types type,
u32 attr, int channel)
{
umode_t mode = 0;
switch (type) {
case hwmon_chip:
switch (attr) {
case hwmon_chip_alarms:
mode = 0444;
break;
default:
break;
}
break;
case hwmon_intrusion:
switch (attr) {
case hwmon_intrusion_alarm:
mode = 0644;
break;
default:
break;
}
break;
case hwmon_temp:
switch (attr) {
case hwmon_temp:
case hwmon_temp_alarm:
mode = 0444;
break;
case hwmon_temp_max:
case hwmon_temp_max_hyst:
mode = 0644;
break;
default:
break;
}
break;
case hwmon_fan:
switch (attr) {
case hwmon_fan_input:
case hwmon_fan_div:
case hwmon_fan_alarm:
mode = 0444;
break;
case hwmon_fan_min:
mode = 0644;
break;
default:
break;
}
break;
case hwmon_in:
switch (attr) {
case hwmon_in_input:
case hwmon_in_alarm:
mode = 0444;
break;
case hwmon_in_min:
case hwmon_in_max:
mode = 0644;
break;
default:
break;
}
break;
default:
break;
}
return mode;
}
static const struct hwmon_ops adm9240_hwmon_ops = {
.is_visible = adm9240_is_visible,
.read = adm9240_read,
.write = adm9240_write,
};
static const struct hwmon_channel_info *adm9240_info[] = {
HWMON_CHANNEL_INFO(chip, HWMON_C_ALARMS),
HWMON_CHANNEL_INFO(intrusion, HWMON_INTRUSION_ALARM),
HWMON_CHANNEL_INFO(temp,
HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST | HWMON_T_ALARM),
HWMON_CHANNEL_INFO(in,
HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM),
HWMON_CHANNEL_INFO(fan,
HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_DIV | HWMON_F_ALARM,
HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_DIV | HWMON_F_ALARM),
NULL
};
static const struct hwmon_chip_info adm9240_chip_info = {
.ops = &adm9240_hwmon_ops,
.info = adm9240_info,
};
static bool adm9240_volatile_reg(struct device *dev, unsigned int reg)
{
switch (reg) {
case ADM9240_REG_IN(0) ... ADM9240_REG_IN(5):
case ADM9240_REG_FAN(0) ... ADM9240_REG_FAN(1):
case ADM9240_REG_INT(0) ... ADM9240_REG_INT(1):
case ADM9240_REG_TEMP:
case ADM9240_REG_TEMP_CONF:
case ADM9240_REG_VID_FAN_DIV:
case ADM9240_REG_VID4:
case ADM9240_REG_ANALOG_OUT:
return true;
default:
return false;
}
}
static const struct regmap_config adm9240_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.use_single_read = true,
.use_single_write = true,
.volatile_reg = adm9240_volatile_reg,
};
static int adm9240_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
struct device *hwmon_dev;
struct adm9240_data *data;
int err;
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->dev = dev;
mutex_init(&data->update_lock);
data->regmap = devm_regmap_init_i2c(client, &adm9240_regmap_config);
if (IS_ERR(data->regmap))
return PTR_ERR(data->regmap);
err = adm9240_init_client(data);
if (err < 0)
return err;
hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, data,
&adm9240_chip_info,
adm9240_groups);
return PTR_ERR_OR_ZERO(hwmon_dev);
}
static const struct i2c_device_id adm9240_id[] = {
{ "adm9240", adm9240 },
{ "ds1780", ds1780 },
{ "lm81", lm81 },
{ }
};
MODULE_DEVICE_TABLE(i2c, adm9240_id);
static struct i2c_driver adm9240_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "adm9240",
},
.probe_new = adm9240_probe,
.id_table = adm9240_id,
.detect = adm9240_detect,
.address_list = normal_i2c,
};
module_i2c_driver(adm9240_driver);
MODULE_AUTHOR("Michiel Rook <michiel@grendelproject.nl>, "
"Grant Coady <gcoady.lk@gmail.com> and others");
MODULE_DESCRIPTION("ADM9240/DS1780/LM81 driver");
MODULE_LICENSE("GPL");