hwmon: add support for GMT G760A fan speed PWM controller
This controller can be found on the D-Link DNS-323 for instance, where it is to be configured via static i2c_board_info in the board-specific mach-orion/dns323-setup.c; this driver supports only the new-style driver model. Tested-by: Martin Michlmayr <tbm@cyrius.com> Signed-off-by: Herbert Valerio Riedel <hvr@gnu.org> Signed-off-by: Matthew Palmer <mpalmer@debian.org> Signed-off-by: Laurie Bradshaw <bradshaw.laurie@googlemail.com> Signed-off-by: Martin Michlmayr <tbm@cyrius.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Herbert Valerio Riedel
Linus Torvalds
parent
6260a4b052
commit
3bcfa9e47a
|
|
@ -0,0 +1,36 @@
|
|||
Kernel driver g760a
|
||||
===================
|
||||
|
||||
Supported chips:
|
||||
* Global Mixed-mode Technology Inc. G760A
|
||||
Prefix: 'g760a'
|
||||
Datasheet: Publicly available at the GMT website
|
||||
http://www.gmt.com.tw/datasheet/g760a.pdf
|
||||
|
||||
Author: Herbert Valerio Riedel <hvr@gnu.org>
|
||||
|
||||
Description
|
||||
-----------
|
||||
|
||||
The GMT G760A Fan Speed PWM Controller is connected directly to a fan
|
||||
and performs closed-loop control of the fan speed.
|
||||
|
||||
The fan speed is programmed by setting the period via 'pwm1' of two
|
||||
consecutive speed pulses. The period is defined in terms of clock
|
||||
cycle counts of an assumed 32kHz clock source.
|
||||
|
||||
Setting a period of 0 stops the fan; setting the period to 255 sets
|
||||
fan to maximum speed.
|
||||
|
||||
The measured fan rotation speed returned via 'fan1_input' is derived
|
||||
from the measured speed pulse period by assuming again a 32kHz clock
|
||||
source and a 2 pulse-per-revolution fan.
|
||||
|
||||
The 'alarms' file provides access to the two alarm bits provided by
|
||||
the G760A chip's status register: Bit 0 is set when the actual fan
|
||||
speed differs more than 20% with respect to the programmed fan speed;
|
||||
bit 1 is set when fan speed is below 1920 RPM.
|
||||
|
||||
The g760a driver will not update its values more frequently than every
|
||||
other second; reading them more often will do no harm, but will return
|
||||
'old' values.
|
||||
|
|
@ -358,6 +358,16 @@ config SENSORS_FSCHMD
|
|||
This driver can also be built as a module. If so, the module
|
||||
will be called fschmd.
|
||||
|
||||
config SENSORS_G760A
|
||||
tristate "GMT G760A"
|
||||
depends on I2C
|
||||
help
|
||||
If you say yes here you get support for Global Mixed-mode
|
||||
Technology Inc G760A fan speed PWM controller chips.
|
||||
|
||||
This driver can also be built as a module. If so, the module
|
||||
will be called g760a.
|
||||
|
||||
config SENSORS_GL518SM
|
||||
tristate "Genesys Logic GL518SM"
|
||||
depends on I2C
|
||||
|
|
|
|||
|
|
@ -42,6 +42,7 @@ obj-$(CONFIG_SENSORS_F75375S) += f75375s.o
|
|||
obj-$(CONFIG_SENSORS_FSCHER) += fscher.o
|
||||
obj-$(CONFIG_SENSORS_FSCHMD) += fschmd.o
|
||||
obj-$(CONFIG_SENSORS_FSCPOS) += fscpos.o
|
||||
obj-$(CONFIG_SENSORS_G760A) += g760a.o
|
||||
obj-$(CONFIG_SENSORS_GL518SM) += gl518sm.o
|
||||
obj-$(CONFIG_SENSORS_GL520SM) += gl520sm.o
|
||||
obj-$(CONFIG_SENSORS_ULTRA45) += ultra45_env.o
|
||||
|
|
|
|||
|
|
@ -0,0 +1,272 @@
|
|||
/*
|
||||
g760a - Driver for the Global Mixed-mode Technology Inc. G760A
|
||||
fan speed PWM controller chip
|
||||
|
||||
Copyright (C) 2007 Herbert Valerio Riedel <hvr@gnu.org>
|
||||
|
||||
Complete datasheet is available at GMT's website:
|
||||
http://www.gmt.com.tw/datasheet/g760a.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.
|
||||
*/
|
||||
|
||||
#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 struct i2c_device_id g760a_id[] = {
|
||||
{ "g760a", 0 },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(i2c, g760a_id);
|
||||
|
||||
enum g760a_regs {
|
||||
G760A_REG_SET_CNT = 0x00,
|
||||
G760A_REG_ACT_CNT = 0x01,
|
||||
G760A_REG_FAN_STA = 0x02
|
||||
};
|
||||
|
||||
#define G760A_REG_FAN_STA_RPM_OFF 0x1 /* +/-20% off */
|
||||
#define G760A_REG_FAN_STA_RPM_LOW 0x2 /* below 1920rpm */
|
||||
|
||||
/* register data is read (and cached) at most once per second */
|
||||
#define G760A_UPDATE_INTERVAL (HZ)
|
||||
|
||||
struct g760a_data {
|
||||
struct i2c_client *client;
|
||||
struct device *hwmon_dev;
|
||||
struct mutex update_lock;
|
||||
|
||||
/* board specific parameters */
|
||||
u32 clk; /* default 32kHz */
|
||||
u16 fan_div; /* default P=2 */
|
||||
|
||||
/* g760a register cache */
|
||||
unsigned int valid:1;
|
||||
unsigned long last_updated; /* In jiffies */
|
||||
|
||||
u8 set_cnt; /* PWM (period) count number; 0xff stops fan */
|
||||
u8 act_cnt; /* formula: cnt = (CLK * 30)/(rpm * P) */
|
||||
u8 fan_sta; /* bit 0: set when actual fan speed more than 20%
|
||||
* outside requested fan speed
|
||||
* bit 1: set when fan speed below 1920 rpm */
|
||||
};
|
||||
|
||||
#define G760A_DEFAULT_CLK 32768
|
||||
#define G760A_DEFAULT_FAN_DIV 2
|
||||
|
||||
#define PWM_FROM_CNT(cnt) (0xff-(cnt))
|
||||
#define PWM_TO_CNT(pwm) (0xff-(pwm))
|
||||
|
||||
unsigned int rpm_from_cnt(u8 val, u32 clk, u16 div)
|
||||
{
|
||||
return ((val == 0x00) ? 0 : ((clk*30)/(val*div)));
|
||||
}
|
||||
|
||||
/* new-style driver model */
|
||||
static int g760a_probe(struct i2c_client *client,
|
||||
const struct i2c_device_id *id);
|
||||
static int g760a_remove(struct i2c_client *client);
|
||||
|
||||
static struct i2c_driver g760a_driver = {
|
||||
.driver = {
|
||||
.name = "g760a",
|
||||
},
|
||||
.probe = g760a_probe,
|
||||
.remove = g760a_remove,
|
||||
.id_table = g760a_id,
|
||||
};
|
||||
|
||||
/* read/write wrappers */
|
||||
static int g760a_read_value(struct i2c_client *client, enum g760a_regs reg)
|
||||
{
|
||||
return i2c_smbus_read_byte_data(client, reg);
|
||||
}
|
||||
|
||||
static int g760a_write_value(struct i2c_client *client, enum g760a_regs reg,
|
||||
u16 value)
|
||||
{
|
||||
return i2c_smbus_write_byte_data(client, reg, value);
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* sysfs attributes
|
||||
*/
|
||||
|
||||
static struct g760a_data *g760a_update_client(struct device *dev)
|
||||
{
|
||||
struct i2c_client *client = to_i2c_client(dev);
|
||||
struct g760a_data *data = i2c_get_clientdata(client);
|
||||
|
||||
mutex_lock(&data->update_lock);
|
||||
|
||||
if (time_after(jiffies, data->last_updated + G760A_UPDATE_INTERVAL)
|
||||
|| !data->valid) {
|
||||
dev_dbg(&client->dev, "Starting g760a update\n");
|
||||
|
||||
data->set_cnt = g760a_read_value(client, G760A_REG_SET_CNT);
|
||||
data->act_cnt = g760a_read_value(client, G760A_REG_ACT_CNT);
|
||||
data->fan_sta = g760a_read_value(client, G760A_REG_FAN_STA);
|
||||
|
||||
data->last_updated = jiffies;
|
||||
data->valid = 1;
|
||||
}
|
||||
|
||||
mutex_unlock(&data->update_lock);
|
||||
|
||||
return data;
|
||||
}
|
||||
|
||||
static ssize_t show_fan(struct device *dev, struct device_attribute *da,
|
||||
char *buf)
|
||||
{
|
||||
struct g760a_data *data = g760a_update_client(dev);
|
||||
unsigned int rpm = 0;
|
||||
|
||||
mutex_lock(&data->update_lock);
|
||||
if (!(data->fan_sta & G760A_REG_FAN_STA_RPM_LOW))
|
||||
rpm = rpm_from_cnt(data->act_cnt, data->clk, data->fan_div);
|
||||
mutex_unlock(&data->update_lock);
|
||||
|
||||
return sprintf(buf, "%d\n", rpm);
|
||||
}
|
||||
|
||||
static ssize_t show_fan_alarm(struct device *dev, struct device_attribute *da,
|
||||
char *buf)
|
||||
{
|
||||
struct g760a_data *data = g760a_update_client(dev);
|
||||
|
||||
int fan_alarm = (data->fan_sta & G760A_REG_FAN_STA_RPM_OFF) ? 1 : 0;
|
||||
|
||||
return sprintf(buf, "%d\n", fan_alarm);
|
||||
}
|
||||
|
||||
static ssize_t get_pwm(struct device *dev, struct device_attribute *da,
|
||||
char *buf)
|
||||
{
|
||||
struct g760a_data *data = g760a_update_client(dev);
|
||||
|
||||
return sprintf(buf, "%d\n", PWM_FROM_CNT(data->set_cnt));
|
||||
}
|
||||
|
||||
static ssize_t set_pwm(struct device *dev, struct device_attribute *da,
|
||||
const char *buf, size_t count)
|
||||
{
|
||||
struct i2c_client *client = to_i2c_client(dev);
|
||||
struct g760a_data *data = g760a_update_client(dev);
|
||||
unsigned long val;
|
||||
|
||||
if (strict_strtoul(buf, 10, &val))
|
||||
return -EINVAL;
|
||||
|
||||
mutex_lock(&data->update_lock);
|
||||
data->set_cnt = PWM_TO_CNT(SENSORS_LIMIT(val, 0, 255));
|
||||
g760a_write_value(client, G760A_REG_SET_CNT, data->set_cnt);
|
||||
mutex_unlock(&data->update_lock);
|
||||
|
||||
return count;
|
||||
}
|
||||
|
||||
static DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, get_pwm, set_pwm);
|
||||
static DEVICE_ATTR(fan1_input, S_IRUGO, show_fan, NULL);
|
||||
static DEVICE_ATTR(fan1_alarm, S_IRUGO, show_fan_alarm, NULL);
|
||||
|
||||
static struct attribute *g760a_attributes[] = {
|
||||
&dev_attr_pwm1.attr,
|
||||
&dev_attr_fan1_input.attr,
|
||||
&dev_attr_fan1_alarm.attr,
|
||||
NULL
|
||||
};
|
||||
|
||||
static const struct attribute_group g760a_group = {
|
||||
.attrs = g760a_attributes,
|
||||
};
|
||||
|
||||
/****************************************************************************
|
||||
* new-style driver model code
|
||||
*/
|
||||
|
||||
static int g760a_probe(struct i2c_client *client,
|
||||
const struct i2c_device_id *id)
|
||||
{
|
||||
struct g760a_data *data;
|
||||
int err;
|
||||
|
||||
if (!i2c_check_functionality(client->adapter,
|
||||
I2C_FUNC_SMBUS_BYTE_DATA))
|
||||
return -EIO;
|
||||
|
||||
data = kzalloc(sizeof(struct g760a_data), GFP_KERNEL);
|
||||
if (!data)
|
||||
return -ENOMEM;
|
||||
|
||||
i2c_set_clientdata(client, data);
|
||||
|
||||
data->client = client;
|
||||
mutex_init(&data->update_lock);
|
||||
|
||||
/* setup default configuration for now */
|
||||
data->fan_div = G760A_DEFAULT_FAN_DIV;
|
||||
data->clk = G760A_DEFAULT_CLK;
|
||||
|
||||
/* Register sysfs hooks */
|
||||
err = sysfs_create_group(&client->dev.kobj, &g760a_group);
|
||||
if (err)
|
||||
goto error_sysfs_create_group;
|
||||
|
||||
data->hwmon_dev = hwmon_device_register(&client->dev);
|
||||
if (IS_ERR(data->hwmon_dev)) {
|
||||
err = PTR_ERR(data->hwmon_dev);
|
||||
goto error_hwmon_device_register;
|
||||
}
|
||||
|
||||
return 0;
|
||||
|
||||
error_hwmon_device_register:
|
||||
sysfs_remove_group(&client->dev.kobj, &g760a_group);
|
||||
error_sysfs_create_group:
|
||||
kfree(data);
|
||||
i2c_set_clientdata(client, NULL);
|
||||
|
||||
return err;
|
||||
}
|
||||
|
||||
static int g760a_remove(struct i2c_client *client)
|
||||
{
|
||||
struct g760a_data *data = i2c_get_clientdata(client);
|
||||
hwmon_device_unregister(data->hwmon_dev);
|
||||
sysfs_remove_group(&client->dev.kobj, &g760a_group);
|
||||
kfree(data);
|
||||
i2c_set_clientdata(client, NULL);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* module management */
|
||||
|
||||
static int __init g760a_init(void)
|
||||
{
|
||||
return i2c_add_driver(&g760a_driver);
|
||||
}
|
||||
|
||||
static void __exit g760a_exit(void)
|
||||
{
|
||||
i2c_del_driver(&g760a_driver);
|
||||
}
|
||||
|
||||
MODULE_AUTHOR("Herbert Valerio Riedel <hvr@gnu.org>");
|
||||
MODULE_DESCRIPTION("GMT G760A driver");
|
||||
MODULE_LICENSE("GPL");
|
||||
|
||||
module_init(g760a_init);
|
||||
module_exit(g760a_exit);
|
||||
Loading…
Reference in New Issue