Commit dd6478d6 authored by Maciej S. Szmigiero's avatar Maciej S. Szmigiero Committed by Greg Kroah-Hartman
Browse files

w1: add DS2405 addressable switch driver 



This adds a driver for a DS2405 1-wire single-channel addressable switch.
The DS2405 can also work as a single-channel binary remote sensor.

This driver supports two attributes: "state" and "output" which are the
same attribute names as supported by existing DS2406, DS2408 and DS2413
drivers.

Signed-off-by: default avatarMaciej S. Szmigiero <mail@maciej.szmigiero.name>
Acked-by: default avatarEvgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 61cd1b4c

drivers/w1/slaves/Kconfig

+8 −0
Original line number Diff line number Diff line
@@ -16,6 +16,14 @@ config W1_SLAVE_SMEM 
	  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"

	help

	  Say Y or M here if you want to use a DS2405 1-wire

	  single-channel addressable switch.

	  This device can also work as a single-channel

	  binary remote sensor.



config W1_SLAVE_DS2408

	tristate "8-Channel Addressable Switch (IO Expander) 0x29 family support (DS2408)"

	help

drivers/w1/slaves/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -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_DS2408)	+= w1_ds2408.o

obj-$(CONFIG_W1_SLAVE_DS2413)	+= w1_ds2413.o

obj-$(CONFIG_W1_SLAVE_DS2406)	+= w1_ds2406.o

drivers/w1/slaves/w1_ds2405.c

0 → 100644
+238 −0
Original line number Diff line number Diff line 
/*

 *	w1_ds2405.c

 *

 * Copyright (c) 2017 Maciej S. Szmigiero <mail@maciej.szmigiero.name>

 * Based on w1_therm.c copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net>

 *

 *

 * 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.

 */



#include <linux/device.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/moduleparam.h>

#include <linux/mutex.h>

#include <linux/string.h>

#include <linux/types.h>



#include "../w1.h"

#include "../w1_family.h"



MODULE_LICENSE("GPL");

MODULE_AUTHOR("Maciej S. Szmigiero <mail@maciej.szmigiero.name>");

MODULE_DESCRIPTION("Driver for 1-wire Dallas DS2405 PIO.");

MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_DS2405));



static int w1_ds2405_select(struct w1_slave *sl, bool only_active)

{

	struct w1_master *dev = sl->master;



	u64 dev_addr = le64_to_cpu(*(u64 *)&sl->reg_num);

	unsigned int bit_ctr;



	if (w1_reset_bus(dev) != 0)

		return 0;



	/*

	 * We cannot use a normal Match ROM command

	 * since doing so would toggle PIO state

	 */

	w1_write_8(dev, only_active ? W1_ALARM_SEARCH : W1_SEARCH);



	for (bit_ctr = 0; bit_ctr < 64; bit_ctr++) {

		int bit2send = !!(dev_addr & BIT(bit_ctr));

		u8 ret;



		ret = w1_triplet(dev, bit2send);



		if ((ret & (BIT(0) | BIT(1))) ==

		    (BIT(0) | BIT(1))) /* no devices found */

			return 0;



		if (!!(ret & BIT(2)) != bit2send)

			/* wrong direction taken - no such device */

			return 0;

	}



	return 1;

}



static int w1_ds2405_read_pio(struct w1_slave *sl)

{

	if (w1_ds2405_select(sl, true))

		return 0; /* "active" means PIO is low */



	if (w1_ds2405_select(sl, false))

		return 1;



	return -ENODEV;

}



static ssize_t state_show(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->bus_mutex);

	if (ret)

		return ret;



	if (!w1_ds2405_select(sl, false)) {

		f_retval = -ENODEV;

		goto out_unlock;

	}



	state = w1_read_8(dev);

	if (state != 0 &&

	    state != 0xff) {

		dev_err(device, "non-consistent state %x\n", state);

		f_retval = -EIO;

		goto out_unlock;

	}



	*buf = state ? '1' : '0';

	f_retval = 1;



out_unlock:

	w1_reset_bus(dev);

	mutex_unlock(&dev->bus_mutex);



	return f_retval;

}



static ssize_t output_show(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->bus_mutex);

	if (ret)

		return ret;



	ret = w1_ds2405_read_pio(sl);

	if (ret < 0) {

		f_retval = ret;

		goto out_unlock;

	}



	*buf = ret ? '1' : '0';

	f_retval = 1;



out_unlock:

	w1_reset_bus(dev);

	mutex_unlock(&dev->bus_mutex);



	return f_retval;

}



static ssize_t output_store(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;



	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->bus_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;

	}



	/*

	 * can't use w1_reset_select_slave() here since it uses Skip ROM if

	 * there is only one device on bus

	 */

	do {

		u64 dev_addr = le64_to_cpu(*(u64 *)&sl->reg_num);

		u8 cmd[9];



		cmd[0] = W1_MATCH_ROM;

		memcpy(&cmd[1], &dev_addr, sizeof(dev_addr));



		w1_write_block(dev, cmd, sizeof(cmd));

	} while (0);



out_unlock:

	w1_reset_bus(dev);

	mutex_unlock(&dev->bus_mutex);



	return f_retval;

}



static DEVICE_ATTR_RO(state);

static DEVICE_ATTR_RW(output);



static struct attribute *w1_ds2405_attrs[] = {

	&dev_attr_state.attr,

	&dev_attr_output.attr,

	NULL

};



ATTRIBUTE_GROUPS(w1_ds2405);



static struct w1_family_ops w1_ds2405_fops = {

	.groups = w1_ds2405_groups

};



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);

drivers/w1/w1_family.h

+1 −0
Original line number Diff line number Diff line
@@ -30,6 +30,7 @@ 
#define W1_FAMILY_BQ27000	0x01

#define W1_FAMILY_SMEM_01	0x01

#define W1_FAMILY_SMEM_81	0x81

#define W1_FAMILY_DS2405	0x05

#define W1_THERM_DS18S20 	0x10

#define W1_FAMILY_DS28E04	0x1C

#define W1_COUNTER_DS2423	0x1D

drivers/w1/w1_io.c

+1 −0
Original line number Diff line number Diff line
@@ -233,6 +233,7 @@ u8 w1_triplet(struct w1_master *dev, int bdir) 
		return retval;

	}

}

EXPORT_SYMBOL_GPL(w1_triplet);



/**

 * w1_read_8() - Reads 8 bits.

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