forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
154 lines
3.3 KiB
154 lines
3.3 KiB
// SPDX-License-Identifier: GPL-2.0-only |
|
/* |
|
* w1_ds2406.c - w1 family 12 (DS2406) driver |
|
* based on w1_ds2413.c by Mariusz Bialonczyk <[email protected]> |
|
* |
|
* Copyright (c) 2014 Scott Alfter <[email protected]> |
|
*/ |
|
|
|
#include <linux/kernel.h> |
|
#include <linux/module.h> |
|
#include <linux/moduleparam.h> |
|
#include <linux/device.h> |
|
#include <linux/types.h> |
|
#include <linux/delay.h> |
|
#include <linux/slab.h> |
|
#include <linux/crc16.h> |
|
|
|
#include <linux/w1.h> |
|
|
|
#define W1_FAMILY_DS2406 0x12 |
|
|
|
#define W1_F12_FUNC_READ_STATUS 0xAA |
|
#define W1_F12_FUNC_WRITE_STATUS 0x55 |
|
|
|
static ssize_t w1_f12_read_state( |
|
struct file *filp, struct kobject *kobj, |
|
struct bin_attribute *bin_attr, |
|
char *buf, loff_t off, size_t count) |
|
{ |
|
u8 w1_buf[6]={W1_F12_FUNC_READ_STATUS, 7, 0, 0, 0, 0}; |
|
struct w1_slave *sl = kobj_to_w1_slave(kobj); |
|
u16 crc=0; |
|
int i; |
|
ssize_t rtnval=1; |
|
|
|
if (off != 0) |
|
return 0; |
|
if (!buf) |
|
return -EINVAL; |
|
|
|
mutex_lock(&sl->master->bus_mutex); |
|
|
|
if (w1_reset_select_slave(sl)) { |
|
mutex_unlock(&sl->master->bus_mutex); |
|
return -EIO; |
|
} |
|
|
|
w1_write_block(sl->master, w1_buf, 3); |
|
w1_read_block(sl->master, w1_buf+3, 3); |
|
for (i=0; i<6; i++) |
|
crc=crc16_byte(crc, w1_buf[i]); |
|
if (crc==0xb001) /* good read? */ |
|
*buf=((w1_buf[3]>>5)&3)|0x30; |
|
else |
|
rtnval=-EIO; |
|
|
|
mutex_unlock(&sl->master->bus_mutex); |
|
|
|
return rtnval; |
|
} |
|
|
|
static ssize_t w1_f12_write_output( |
|
struct file *filp, struct kobject *kobj, |
|
struct bin_attribute *bin_attr, |
|
char *buf, loff_t off, size_t count) |
|
{ |
|
struct w1_slave *sl = kobj_to_w1_slave(kobj); |
|
u8 w1_buf[6]={W1_F12_FUNC_WRITE_STATUS, 7, 0, 0, 0, 0}; |
|
u16 crc=0; |
|
int i; |
|
ssize_t rtnval=1; |
|
|
|
if (count != 1 || off != 0) |
|
return -EFAULT; |
|
|
|
mutex_lock(&sl->master->bus_mutex); |
|
|
|
if (w1_reset_select_slave(sl)) { |
|
mutex_unlock(&sl->master->bus_mutex); |
|
return -EIO; |
|
} |
|
|
|
w1_buf[3] = (((*buf)&3)<<5)|0x1F; |
|
w1_write_block(sl->master, w1_buf, 4); |
|
w1_read_block(sl->master, w1_buf+4, 2); |
|
for (i=0; i<6; i++) |
|
crc=crc16_byte(crc, w1_buf[i]); |
|
if (crc==0xb001) /* good read? */ |
|
w1_write_8(sl->master, 0xFF); |
|
else |
|
rtnval=-EIO; |
|
|
|
mutex_unlock(&sl->master->bus_mutex); |
|
return rtnval; |
|
} |
|
|
|
#define NB_SYSFS_BIN_FILES 2 |
|
static struct bin_attribute w1_f12_sysfs_bin_files[NB_SYSFS_BIN_FILES] = { |
|
{ |
|
.attr = { |
|
.name = "state", |
|
.mode = S_IRUGO, |
|
}, |
|
.size = 1, |
|
.read = w1_f12_read_state, |
|
}, |
|
{ |
|
.attr = { |
|
.name = "output", |
|
.mode = S_IRUGO | S_IWUSR | S_IWGRP, |
|
}, |
|
.size = 1, |
|
.write = w1_f12_write_output, |
|
} |
|
}; |
|
|
|
static int w1_f12_add_slave(struct w1_slave *sl) |
|
{ |
|
int err = 0; |
|
int i; |
|
|
|
for (i = 0; i < NB_SYSFS_BIN_FILES && !err; ++i) |
|
err = sysfs_create_bin_file( |
|
&sl->dev.kobj, |
|
&(w1_f12_sysfs_bin_files[i])); |
|
if (err) |
|
while (--i >= 0) |
|
sysfs_remove_bin_file(&sl->dev.kobj, |
|
&(w1_f12_sysfs_bin_files[i])); |
|
return err; |
|
} |
|
|
|
static void w1_f12_remove_slave(struct w1_slave *sl) |
|
{ |
|
int i; |
|
for (i = NB_SYSFS_BIN_FILES - 1; i >= 0; --i) |
|
sysfs_remove_bin_file(&sl->dev.kobj, |
|
&(w1_f12_sysfs_bin_files[i])); |
|
} |
|
|
|
static const struct w1_family_ops w1_f12_fops = { |
|
.add_slave = w1_f12_add_slave, |
|
.remove_slave = w1_f12_remove_slave, |
|
}; |
|
|
|
static struct w1_family w1_family_12 = { |
|
.fid = W1_FAMILY_DS2406, |
|
.fops = &w1_f12_fops, |
|
}; |
|
module_w1_family(w1_family_12); |
|
|
|
MODULE_AUTHOR("Scott Alfter <[email protected]>"); |
|
MODULE_DESCRIPTION("w1 family 12 driver for DS2406 2 Pin IO"); |
|
MODULE_LICENSE("GPL");
|
|
|