[mirror_ubuntu-zesty-kernel.git] / drivers / w1 / slaves / w1_ds2413.c

/*
 * w1_ds2413.c - w1 family 3a (DS2413) driver
 * based on w1_ds2408.c by Jean-Francois Dagenais <dagenaisj@sonatest.com>
 *
 * Copyright (c) 2013 Mariusz Bialonczyk <manio@skyboo.net>
 *
 * This source code is licensed under the GNU General Public License,
 * Version 2. See the file COPYING for more details.
 */

#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 "../w1.h"
#include "../w1_int.h"
#include "../w1_family.h"

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Mariusz Bialonczyk <manio@skyboo.net>");
MODULE_DESCRIPTION("w1 family 3a driver for DS2413 2 Pin IO");
MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_DS2413));

#define W1_F3A_RETRIES                     3
#define W1_F3A_FUNC_PIO_ACCESS_READ        0xF5
#define W1_F3A_FUNC_PIO_ACCESS_WRITE       0x5A
#define W1_F3A_SUCCESS_CONFIRM_BYTE        0xAA

static ssize_t state_read(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);
	dev_dbg(&sl->dev,
		"Reading %s kobj: %p, off: %0#10x, count: %zu, buff addr: %p",
		bin_attr->attr.name, kobj, (unsigned int)off, count, buf);

	if (off != 0)
		return 0;
	if (!buf)
		return -EINVAL;

	mutex_lock(&sl->master->bus_mutex);
	dev_dbg(&sl->dev, "mutex locked");

	if (w1_reset_select_slave(sl)) {
		mutex_unlock(&sl->master->bus_mutex);
		return -EIO;
	}

	w1_write_8(sl->master, W1_F3A_FUNC_PIO_ACCESS_READ);
	*buf = w1_read_8(sl->master);

	mutex_unlock(&sl->master->bus_mutex);
	dev_dbg(&sl->dev, "mutex unlocked");

	/* check for correct complement */
	if ((*buf & 0x0F) != ((~*buf >> 4) & 0x0F))
		return -EIO;
	else
		return 1;
}

static BIN_ATTR_RO(state, 1);

static ssize_t output_write(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[3];
	unsigned int retries = W1_F3A_RETRIES;

	if (count != 1 || off != 0)
		return -EFAULT;

	dev_dbg(&sl->dev, "locking mutex for write_output");
	mutex_lock(&sl->master->bus_mutex);
	dev_dbg(&sl->dev, "mutex locked");

	if (w1_reset_select_slave(sl))
		goto error;

	/* according to the DS2413 datasheet the most significant 6 bits
	   should be set to "1"s, so do it now */
	*buf = *buf | 0xFC;

	while (retries--) {
		w1_buf[0] = W1_F3A_FUNC_PIO_ACCESS_WRITE;
		w1_buf[1] = *buf;
		w1_buf[2] = ~(*buf);
		w1_write_block(sl->master, w1_buf, 3);

		if (w1_read_8(sl->master) == W1_F3A_SUCCESS_CONFIRM_BYTE) {
			mutex_unlock(&sl->master->bus_mutex);
			dev_dbg(&sl->dev, "mutex unlocked, retries:%d", retries);
			return 1;
		}
		if (w1_reset_resume_command(sl->master))
			goto error;
	}

error:
	mutex_unlock(&sl->master->bus_mutex);
	dev_dbg(&sl->dev, "mutex unlocked in error, retries:%d", retries);
	return -EIO;
}

static BIN_ATTR(output, S_IRUGO | S_IWUSR | S_IWGRP, NULL, output_write, 1);

static struct bin_attribute *w1_f3a_bin_attrs[] = {
	&bin_attr_state,
	&bin_attr_output,
	NULL,
};

static const struct attribute_group w1_f3a_group = {
	.bin_attrs = w1_f3a_bin_attrs,
};

static const struct attribute_group *w1_f3a_groups[] = {
	&w1_f3a_group,
	NULL,
};

static struct w1_family_ops w1_f3a_fops = {
	.groups		= w1_f3a_groups,
};

static struct w1_family w1_family_3a = {
	.fid = W1_FAMILY_DS2413,
	.fops = &w1_f3a_fops,
};

static int __init w1_f3a_init(void)
{
	return w1_register_family(&w1_family_3a);
}

static void __exit w1_f3a_exit(void)
{
	w1_unregister_family(&w1_family_3a);
}

module_init(w1_f3a_init);
module_exit(w1_f3a_exit);
Commit	Line	Data
31b4ca3e MB	1	/*
	2	* w1_ds2413.c - w1 family 3a (DS2413) driver
	3	* based on w1_ds2408.c by Jean-Francois Dagenais <dagenaisj@sonatest.com>
	4	*
	5	* Copyright (c) 2013 Mariusz Bialonczyk <manio@skyboo.net>
	6	*
	7	* This source code is licensed under the GNU General Public License,
	8	* Version 2. See the file COPYING for more details.
	9	*/
	10
	11	#include <linux/kernel.h>
	12	#include <linux/module.h>
	13	#include <linux/moduleparam.h>
	14	#include <linux/device.h>
	15	#include <linux/types.h>
	16	#include <linux/delay.h>
	17	#include <linux/slab.h>
	18
	19	#include "../w1.h"
	20	#include "../w1_int.h"
	21	#include "../w1_family.h"
	22
	23	MODULE_LICENSE("GPL");
	24	MODULE_AUTHOR("Mariusz Bialonczyk <manio@skyboo.net>");
	25	MODULE_DESCRIPTION("w1 family 3a driver for DS2413 2 Pin IO");
8d7bda51	26	MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_DS2413));
31b4ca3e MB	27
	28	#define W1_F3A_RETRIES 3
	29	#define W1_F3A_FUNC_PIO_ACCESS_READ 0xF5
	30	#define W1_F3A_FUNC_PIO_ACCESS_WRITE 0x5A
	31	#define W1_F3A_SUCCESS_CONFIRM_BYTE 0xAA
	32
729fb9d3 GKH	33	static ssize_t state_read(struct file filp, struct kobject kobj,
	34	struct bin_attribute bin_attr, char buf, loff_t off,
	35	size_t count)
31b4ca3e MB	36	{
	37	struct w1_slave *sl = kobj_to_w1_slave(kobj);
	38	dev_dbg(&sl->dev,
	39	"Reading %s kobj: %p, off: %0#10x, count: %zu, buff addr: %p",
	40	bin_attr->attr.name, kobj, (unsigned int)off, count, buf);
	41
	42	if (off != 0)
	43	return 0;
	44	if (!buf)
	45	return -EINVAL;
	46
	47	mutex_lock(&sl->master->bus_mutex);
	48	dev_dbg(&sl->dev, "mutex locked");
	49
	50	if (w1_reset_select_slave(sl)) {
	51	mutex_unlock(&sl->master->bus_mutex);
	52	return -EIO;
	53	}
	54
	55	w1_write_8(sl->master, W1_F3A_FUNC_PIO_ACCESS_READ);
	56	*buf = w1_read_8(sl->master);
	57
	58	mutex_unlock(&sl->master->bus_mutex);
	59	dev_dbg(&sl->dev, "mutex unlocked");
	60
	61	/* check for correct complement */
	62	if ((buf & 0x0F) != ((~buf >> 4) & 0x0F))
	63	return -EIO;
	64	else
	65	return 1;
	66	}
	67
729fb9d3 GKH	68	static BIN_ATTR_RO(state, 1);
	69
	70	static ssize_t output_write(struct file filp, struct kobject kobj,
	71	struct bin_attribute bin_attr, char buf,
	72	loff_t off, size_t count)
31b4ca3e MB	73	{
	74	struct w1_slave *sl = kobj_to_w1_slave(kobj);
	75	u8 w1_buf[3];
	76	unsigned int retries = W1_F3A_RETRIES;
	77
	78	if (count != 1 \|\| off != 0)
	79	return -EFAULT;
	80
	81	dev_dbg(&sl->dev, "locking mutex for write_output");
	82	mutex_lock(&sl->master->bus_mutex);
	83	dev_dbg(&sl->dev, "mutex locked");
	84
	85	if (w1_reset_select_slave(sl))
	86	goto error;
	87
	88	/* according to the DS2413 datasheet the most significant 6 bits
	89	should be set to "1"s, so do it now */
	90	buf = buf \| 0xFC;
	91
	92	while (retries--) {
	93	w1_buf[0] = W1_F3A_FUNC_PIO_ACCESS_WRITE;
	94	w1_buf[1] = *buf;
	95	w1_buf[2] = ~(*buf);
	96	w1_write_block(sl->master, w1_buf, 3);
	97
	98	if (w1_read_8(sl->master) == W1_F3A_SUCCESS_CONFIRM_BYTE) {
	99	mutex_unlock(&sl->master->bus_mutex);
	100	dev_dbg(&sl->dev, "mutex unlocked, retries:%d", retries);
	101	return 1;
	102	}
	103	if (w1_reset_resume_command(sl->master))
	104	goto error;
	105	}
	106
	107	error:
	108	mutex_unlock(&sl->master->bus_mutex);
	109	dev_dbg(&sl->dev, "mutex unlocked in error, retries:%d", retries);
	110	return -EIO;
	111	}
	112
729fb9d3 GKH	113	static BIN_ATTR(output, S_IRUGO \| S_IWUSR \| S_IWGRP, NULL, output_write, 1);
	114
	115	static struct bin_attribute *w1_f3a_bin_attrs[] = {
	116	&bin_attr_state,
	117	&bin_attr_output,
	118	NULL,
31b4ca3e MB	119	};
31b4ca3e MB	120
729fb9d3 GKH	121	static const struct attribute_group w1_f3a_group = {
	122	.bin_attrs = w1_f3a_bin_attrs,
	123	};
31b4ca3e	124
729fb9d3 GKH	125	static const struct attribute_group *w1_f3a_groups[] = {
	126	&w1_f3a_group,
	127	NULL,
	128	};
31b4ca3e MB	129
31b4ca3e MB	130	static struct w1_family_ops w1_f3a_fops = {
729fb9d3	131	.groups = w1_f3a_groups,
31b4ca3e MB	132	};
	133
	134	static struct w1_family w1_family_3a = {
	135	.fid = W1_FAMILY_DS2413,
	136	.fops = &w1_f3a_fops,
	137	};
	138
	139	static int __init w1_f3a_init(void)
	140	{
	141	return w1_register_family(&w1_family_3a);
	142	}
	143
	144	static void __exit w1_f3a_exit(void)
	145	{
	146	w1_unregister_family(&w1_family_3a);
	147	}
	148
	149	module_init(w1_f3a_init);
	150	module_exit(w1_f3a_exit);