Messages in this thread Patch in this message | | | Date | Thu, 28 Oct 2010 22:52:53 +0200 | From | Maciej Szmigiero <> | Subject | [W1] a driver for DS2405 chip |
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[W1] a driver for DS2405 chip
This is a driver for DS2405 1-wire single-channel addressable switch / PIO. DS2405 can also work as single-channel binary remote sensor.
Signed-off-by: Maciej Szmigiero <mhej@o2.pl>
--- a/drivers/w1/w1_family.h 2009-06-10 05:05:27.000000000 +0200 +++ b/drivers/w1/w1_family.h 2009-12-13 22:23:32.994770399 +0100 @@ -28,6 +28,7 @@ #define W1_FAMILY_DEFAULT 0 #define W1_FAMILY_SMEM_01 0x01 +#define W1_FAMILY_DS2405 0x05 #define W1_FAMILY_SMEM_81 0x81 #define W1_THERM_DS18S20 0x10 #define W1_THERM_DS1822 0x22 --- a/drivers/w1/w1_io.c 2009-06-10 05:05:27.000000000 +0200 +++ b/drivers/w1/w1_io.c 2009-12-15 22:32:48.362801835 +0100 @@ -210,6 +210,7 @@ return retval; } } +EXPORT_SYMBOL_GPL(w1_triplet); /** * Reads 8 bits. --- /dev/null 2010-10-28 22:18:50.899999998 +0200 +++ b/drivers/w1/slaves/w1_ds2405.c 2010-10-28 22:42:13.000000000 +0200 @@ -0,0 +1,251 @@ +/* + * w1_ds2405.c + * + * Copyright (c) 2009 Maciej Szmigiero <mhej@o2.pl> + * Based on w1_therm.c copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru> + * + * + * This program is free software; you can redistribute it and/or modify + * it under the therms 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/sched.h> +#include <linux/device.h> +#include <linux/types.h> +#include <linux/delay.h> + +#include "../w1.h" +#include "../w1_int.h" +#include "../w1_family.h" + +static int w1_ds2405_select(struct w1_slave *sl, int only_active) +{ + struct w1_master *dev = sl->master; + int ret; + + if (w1_reset_bus(dev) != 0) + return 0; + + /* We cannot use normal Match ROM command */ + /* since doing so would toggle PIO state */ + w1_write_8(dev, only_active ? W1_ALARM_SEARCH : W1_SEARCH); + + do { + u64 dev_addr = cpu_to_le64(((u64)sl->reg_num.crc<<(8+48)) + | ((u64)sl->reg_num.id<<8) + | sl->reg_num.family); + u8 bit_ctr; + + for (bit_ctr = 0; bit_ctr < 64; bit_ctr++) { + int bit2send = !!(dev_addr & 1LL<<bit_ctr); + ret = w1_triplet(dev, bit2send); + + if ((ret & 3) == 3) /* no devices found */ + return 0; + + if ((!!(ret & 4)) != bit2send) + /* wrong direction taken - no such device */ + return 0; + } + } while (0); + + return 1; +} + +static int w1_ds2405_read_pio(struct w1_slave *sl) +{ + if (w1_ds2405_select(sl, 1)) + return 0; /* "active" means PIO is low */ + + if (w1_ds2405_select(sl, 0)) + return 1; + else + return -ENODEV; +} + +static ssize_t w1_ds2405_read_sensed_file(struct device *device, + struct device_attribute *attr, char *buf) +{ + struct w1_slave *sl = dev_to_w1_slave(device); + struct w1_master *dev = sl->master; + + int ret; + ssize_t f_retval; + u8 state; + + ret = mutex_lock_interruptible(&dev->mutex); + if (ret) + return ret; + + if (!w1_ds2405_select(sl, 0)) { + f_retval = -ENODEV; + goto out_unlock; + } + + state = w1_read_8(dev); + + f_retval = snprintf(buf, PAGE_SIZE, "%u\n", !!(state)); + +out_unlock: + w1_reset_bus(dev); + mutex_unlock(&dev->mutex); + + return f_retval; +} + +static ssize_t w1_ds2405_read_pio_file(struct device *device, + struct device_attribute *attr, char *buf) +{ + struct w1_slave *sl = dev_to_w1_slave(device); + struct w1_master *dev = sl->master; + + int ret; + ssize_t f_retval; + + ret = mutex_lock_interruptible(&dev->mutex); + if (ret) + return ret; + + ret = w1_ds2405_read_pio(sl); + if (ret < 0) { + f_retval = ret; + goto out_unlock; + } + + f_retval = snprintf(buf, PAGE_SIZE, "%d\n", ret); + +out_unlock: + w1_reset_bus(dev); + mutex_unlock(&dev->mutex); + + return f_retval; +} + +static ssize_t w1_ds2405_write_pio_file(struct device *device, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct w1_slave *sl = dev_to_w1_slave(device); + struct w1_master *dev = sl->master; + + int ret, current_pio; + unsigned int val; + ssize_t f_retval; + + if (count < 1) + return -EINVAL; + + /* fill_write_buffer() in fs/sysfs/file.c */ + /* keeps the buffer null-terminated */ + if (sscanf(buf, " %u%n", &val, &ret) < 1) + return -EINVAL; + + if ((val != 0) && (val != 1)) + return -EINVAL; + + f_retval = ret; + + ret = mutex_lock_interruptible(&dev->mutex); + if (ret) + return ret; + + current_pio = w1_ds2405_read_pio(sl); + if (current_pio < 0) { + f_retval = current_pio; + goto out_unlock; + } + + if (current_pio == val) + goto out_unlock; + + if (w1_reset_bus(dev) != 0) { + f_retval = -ENODEV; + goto out_unlock; + } + + do { + u64 dev_addr = cpu_to_le64(((u64)sl->reg_num.crc<<(8+48)) + | ((u64)sl->reg_num.id<<8) | sl->reg_num.family); + + w1_write_8(dev, W1_MATCH_ROM); + w1_write_block(dev, (u8 *)&dev_addr, 8); + } while (0); + +out_unlock: + w1_reset_bus(dev); + mutex_unlock(&dev->mutex); + + return f_retval; +} + +static DEVICE_ATTR(sensed, S_IRUSR | S_IRGRP, w1_ds2405_read_sensed_file, NULL); +static DEVICE_ATTR(PIO, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP, + w1_ds2405_read_pio_file, w1_ds2405_write_pio_file); + +static int w1_ds2405_add_slave(struct w1_slave *sl) +{ + int err; + + err = device_create_file(&sl->dev, &dev_attr_sensed); + if (err) + return err; + + err = device_create_file(&sl->dev, &dev_attr_PIO); + if (err) { + device_remove_file(&sl->dev, &dev_attr_sensed); + return err; + } + + return 0; +} + +static void w1_ds2405_remove_slave(struct w1_slave *sl) +{ + device_remove_file(&sl->dev, &dev_attr_sensed); + device_remove_file(&sl->dev, &dev_attr_PIO); +} + + +static struct w1_family_ops w1_ds2405_fops = { + .add_slave = w1_ds2405_add_slave, + .remove_slave = w1_ds2405_remove_slave, +}; + + +static struct w1_family w1_family_ds2405 = { + .fid = W1_FAMILY_DS2405, + .fops = &w1_ds2405_fops, +}; + +static int __init w1_ds2405_init(void) +{ + return w1_register_family(&w1_family_ds2405); +} + +static void __exit w1_ds2405_fini(void) +{ + + w1_unregister_family(&w1_family_ds2405); +} + +module_init(w1_ds2405_init); +module_exit(w1_ds2405_fini); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Maciej Szmigiero <mhej@o2.pl>"); +MODULE_DESCRIPTION("Driver for 1-wire Dallas DS2405 PIO"); --- a/drivers/w1/slaves/Makefile 2010-08-02 00:11:14.000000000 +0200 +++ b/drivers/w1/slaves/Makefile 2010-10-28 22:39:13.000000000 +0200 @@ -4,6 +4,7 @@ obj-$(CONFIG_W1_SLAVE_THERM) += w1_therm.o obj-$(CONFIG_W1_SLAVE_SMEM) += w1_smem.o +obj-$(CONFIG_W1_SLAVE_DS2405) += w1_ds2405.o obj-$(CONFIG_W1_SLAVE_DS2431) += w1_ds2431.o obj-$(CONFIG_W1_SLAVE_DS2433) += w1_ds2433.o obj-$(CONFIG_W1_SLAVE_DS2760) += w1_ds2760.o --- a/drivers/w1/slaves/Kconfig 2010-08-02 00:11:14.000000000 +0200 +++ b/drivers/w1/slaves/Kconfig 2010-10-28 22:37:55.000000000 +0200 @@ -16,6 +16,14 @@ Say Y here if you want to connect 1-wire simple 64bit memory rom(ds2401/ds2411/ds1990*) to your wire. +config W1_SLAVE_DS2405 + tristate "DS2405 Addressable Switch / PIO" + help + Say Y here if you want to build driver for 1-wire + single-channel addressable switch / PIO. + This device can also work as single-channel + binary remote sensor. + config W1_SLAVE_DS2431 tristate "1kb EEPROM family support (DS2431)" help
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