mirror of https://gitee.com/openkylin/linux.git
311 lines
9.0 KiB
C
311 lines
9.0 KiB
C
/*
|
|
pcf8591.c - Part of lm_sensors, Linux kernel modules for hardware
|
|
monitoring
|
|
Copyright (C) 2001-2004 Aurelien Jarno <aurelien@aurel32.net>
|
|
Ported to Linux 2.6 by Aurelien Jarno <aurelien@aurel32.net> with
|
|
the help of Jean Delvare <khali@linux-fr.org>
|
|
|
|
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/i2c.h>
|
|
|
|
/* Addresses to scan */
|
|
static unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
|
|
0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
|
|
|
|
/* Insmod parameters */
|
|
I2C_CLIENT_INSMOD_1(pcf8591);
|
|
|
|
static int input_mode;
|
|
module_param(input_mode, int, 0);
|
|
MODULE_PARM_DESC(input_mode,
|
|
"Analog input mode:\n"
|
|
" 0 = four single ended inputs\n"
|
|
" 1 = three differential inputs\n"
|
|
" 2 = single ended and differential mixed\n"
|
|
" 3 = two differential inputs\n");
|
|
|
|
/* The PCF8591 control byte
|
|
7 6 5 4 3 2 1 0
|
|
| 0 |AOEF| AIP | 0 |AINC| AICH | */
|
|
|
|
/* Analog Output Enable Flag (analog output active if 1) */
|
|
#define PCF8591_CONTROL_AOEF 0x40
|
|
|
|
/* Analog Input Programming
|
|
0x00 = four single ended inputs
|
|
0x10 = three differential inputs
|
|
0x20 = single ended and differential mixed
|
|
0x30 = two differential inputs */
|
|
#define PCF8591_CONTROL_AIP_MASK 0x30
|
|
|
|
/* Autoincrement Flag (switch on if 1) */
|
|
#define PCF8591_CONTROL_AINC 0x04
|
|
|
|
/* Channel selection
|
|
0x00 = channel 0
|
|
0x01 = channel 1
|
|
0x02 = channel 2
|
|
0x03 = channel 3 */
|
|
#define PCF8591_CONTROL_AICH_MASK 0x03
|
|
|
|
/* Initial values */
|
|
#define PCF8591_INIT_CONTROL ((input_mode << 4) | PCF8591_CONTROL_AOEF)
|
|
#define PCF8591_INIT_AOUT 0 /* DAC out = 0 */
|
|
|
|
/* Conversions */
|
|
#define REG_TO_SIGNED(reg) (((reg) & 0x80)?((reg) - 256):(reg))
|
|
|
|
struct pcf8591_data {
|
|
struct i2c_client client;
|
|
struct semaphore update_lock;
|
|
|
|
u8 control;
|
|
u8 aout;
|
|
};
|
|
|
|
static int pcf8591_attach_adapter(struct i2c_adapter *adapter);
|
|
static int pcf8591_detect(struct i2c_adapter *adapter, int address, int kind);
|
|
static int pcf8591_detach_client(struct i2c_client *client);
|
|
static void pcf8591_init_client(struct i2c_client *client);
|
|
static int pcf8591_read_channel(struct device *dev, int channel);
|
|
|
|
/* This is the driver that will be inserted */
|
|
static struct i2c_driver pcf8591_driver = {
|
|
.driver = {
|
|
.name = "pcf8591",
|
|
},
|
|
.id = I2C_DRIVERID_PCF8591,
|
|
.attach_adapter = pcf8591_attach_adapter,
|
|
.detach_client = pcf8591_detach_client,
|
|
};
|
|
|
|
/* following are the sysfs callback functions */
|
|
#define show_in_channel(channel) \
|
|
static ssize_t show_in##channel##_input(struct device *dev, struct device_attribute *attr, char *buf) \
|
|
{ \
|
|
return sprintf(buf, "%d\n", pcf8591_read_channel(dev, channel));\
|
|
} \
|
|
static DEVICE_ATTR(in##channel##_input, S_IRUGO, \
|
|
show_in##channel##_input, NULL);
|
|
|
|
show_in_channel(0);
|
|
show_in_channel(1);
|
|
show_in_channel(2);
|
|
show_in_channel(3);
|
|
|
|
static ssize_t show_out0_ouput(struct device *dev, struct device_attribute *attr, char *buf)
|
|
{
|
|
struct pcf8591_data *data = i2c_get_clientdata(to_i2c_client(dev));
|
|
return sprintf(buf, "%d\n", data->aout * 10);
|
|
}
|
|
|
|
static ssize_t set_out0_output(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
|
|
{
|
|
unsigned int value;
|
|
struct i2c_client *client = to_i2c_client(dev);
|
|
struct pcf8591_data *data = i2c_get_clientdata(client);
|
|
if ((value = (simple_strtoul(buf, NULL, 10) + 5) / 10) <= 255) {
|
|
data->aout = value;
|
|
i2c_smbus_write_byte_data(client, data->control, data->aout);
|
|
return count;
|
|
}
|
|
return -EINVAL;
|
|
}
|
|
|
|
static DEVICE_ATTR(out0_output, S_IWUSR | S_IRUGO,
|
|
show_out0_ouput, set_out0_output);
|
|
|
|
static ssize_t show_out0_enable(struct device *dev, struct device_attribute *attr, char *buf)
|
|
{
|
|
struct pcf8591_data *data = i2c_get_clientdata(to_i2c_client(dev));
|
|
return sprintf(buf, "%u\n", !(!(data->control & PCF8591_CONTROL_AOEF)));
|
|
}
|
|
|
|
static ssize_t set_out0_enable(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
|
|
{
|
|
struct i2c_client *client = to_i2c_client(dev);
|
|
struct pcf8591_data *data = i2c_get_clientdata(client);
|
|
unsigned long val = simple_strtoul(buf, NULL, 10);
|
|
|
|
down(&data->update_lock);
|
|
if (val)
|
|
data->control |= PCF8591_CONTROL_AOEF;
|
|
else
|
|
data->control &= ~PCF8591_CONTROL_AOEF;
|
|
i2c_smbus_write_byte(client, data->control);
|
|
up(&data->update_lock);
|
|
return count;
|
|
}
|
|
|
|
static DEVICE_ATTR(out0_enable, S_IWUSR | S_IRUGO,
|
|
show_out0_enable, set_out0_enable);
|
|
|
|
/*
|
|
* Real code
|
|
*/
|
|
static int pcf8591_attach_adapter(struct i2c_adapter *adapter)
|
|
{
|
|
return i2c_probe(adapter, &addr_data, pcf8591_detect);
|
|
}
|
|
|
|
/* This function is called by i2c_probe */
|
|
static int pcf8591_detect(struct i2c_adapter *adapter, int address, int kind)
|
|
{
|
|
struct i2c_client *new_client;
|
|
struct pcf8591_data *data;
|
|
int err = 0;
|
|
|
|
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE
|
|
| I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
|
|
goto exit;
|
|
|
|
/* OK. For now, we presume we have a valid client. We now create the
|
|
client structure, even though we cannot fill it completely yet. */
|
|
if (!(data = kzalloc(sizeof(struct pcf8591_data), GFP_KERNEL))) {
|
|
err = -ENOMEM;
|
|
goto exit;
|
|
}
|
|
|
|
new_client = &data->client;
|
|
i2c_set_clientdata(new_client, data);
|
|
new_client->addr = address;
|
|
new_client->adapter = adapter;
|
|
new_client->driver = &pcf8591_driver;
|
|
new_client->flags = 0;
|
|
|
|
/* Now, we would do the remaining detection. But the PCF8591 is plainly
|
|
impossible to detect! Stupid chip. */
|
|
|
|
/* Determine the chip type - only one kind supported! */
|
|
if (kind <= 0)
|
|
kind = pcf8591;
|
|
|
|
/* Fill in the remaining client fields and put it into the global
|
|
list */
|
|
strlcpy(new_client->name, "pcf8591", I2C_NAME_SIZE);
|
|
init_MUTEX(&data->update_lock);
|
|
|
|
/* Tell the I2C layer a new client has arrived */
|
|
if ((err = i2c_attach_client(new_client)))
|
|
goto exit_kfree;
|
|
|
|
/* Initialize the PCF8591 chip */
|
|
pcf8591_init_client(new_client);
|
|
|
|
/* Register sysfs hooks */
|
|
device_create_file(&new_client->dev, &dev_attr_out0_enable);
|
|
device_create_file(&new_client->dev, &dev_attr_out0_output);
|
|
device_create_file(&new_client->dev, &dev_attr_in0_input);
|
|
device_create_file(&new_client->dev, &dev_attr_in1_input);
|
|
|
|
/* Register input2 if not in "two differential inputs" mode */
|
|
if (input_mode != 3 )
|
|
device_create_file(&new_client->dev, &dev_attr_in2_input);
|
|
|
|
/* Register input3 only in "four single ended inputs" mode */
|
|
if (input_mode == 0)
|
|
device_create_file(&new_client->dev, &dev_attr_in3_input);
|
|
|
|
return 0;
|
|
|
|
/* OK, this is not exactly good programming practice, usually. But it is
|
|
very code-efficient in this case. */
|
|
|
|
exit_kfree:
|
|
kfree(data);
|
|
exit:
|
|
return err;
|
|
}
|
|
|
|
static int pcf8591_detach_client(struct i2c_client *client)
|
|
{
|
|
int err;
|
|
|
|
if ((err = i2c_detach_client(client)))
|
|
return err;
|
|
|
|
kfree(i2c_get_clientdata(client));
|
|
return 0;
|
|
}
|
|
|
|
/* Called when we have found a new PCF8591. */
|
|
static void pcf8591_init_client(struct i2c_client *client)
|
|
{
|
|
struct pcf8591_data *data = i2c_get_clientdata(client);
|
|
data->control = PCF8591_INIT_CONTROL;
|
|
data->aout = PCF8591_INIT_AOUT;
|
|
|
|
i2c_smbus_write_byte_data(client, data->control, data->aout);
|
|
|
|
/* The first byte transmitted contains the conversion code of the
|
|
previous read cycle. FLUSH IT! */
|
|
i2c_smbus_read_byte(client);
|
|
}
|
|
|
|
static int pcf8591_read_channel(struct device *dev, int channel)
|
|
{
|
|
u8 value;
|
|
struct i2c_client *client = to_i2c_client(dev);
|
|
struct pcf8591_data *data = i2c_get_clientdata(client);
|
|
|
|
down(&data->update_lock);
|
|
|
|
if ((data->control & PCF8591_CONTROL_AICH_MASK) != channel) {
|
|
data->control = (data->control & ~PCF8591_CONTROL_AICH_MASK)
|
|
| channel;
|
|
i2c_smbus_write_byte(client, data->control);
|
|
|
|
/* The first byte transmitted contains the conversion code of
|
|
the previous read cycle. FLUSH IT! */
|
|
i2c_smbus_read_byte(client);
|
|
}
|
|
value = i2c_smbus_read_byte(client);
|
|
|
|
up(&data->update_lock);
|
|
|
|
if ((channel == 2 && input_mode == 2) ||
|
|
(channel != 3 && (input_mode == 1 || input_mode == 3)))
|
|
return (10 * REG_TO_SIGNED(value));
|
|
else
|
|
return (10 * value);
|
|
}
|
|
|
|
static int __init pcf8591_init(void)
|
|
{
|
|
if (input_mode < 0 || input_mode > 3) {
|
|
printk(KERN_WARNING "pcf8591: invalid input_mode (%d)\n",
|
|
input_mode);
|
|
input_mode = 0;
|
|
}
|
|
return i2c_add_driver(&pcf8591_driver);
|
|
}
|
|
|
|
static void __exit pcf8591_exit(void)
|
|
{
|
|
i2c_del_driver(&pcf8591_driver);
|
|
}
|
|
|
|
MODULE_AUTHOR("Aurelien Jarno <aurelien@aurel32.net>");
|
|
MODULE_DESCRIPTION("PCF8591 driver");
|
|
MODULE_LICENSE("GPL");
|
|
|
|
module_init(pcf8591_init);
|
|
module_exit(pcf8591_exit);
|