[linux-block.git] / drivers / w1 / slaves / w1_ds2406.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * w1_ds2406.c - w1 family 12 (DS2406) driver
 * based on w1_ds2413.c by Mariusz Bialonczyk <manio@skyboo.net>
 *
 * Copyright (c) 2014 Scott Alfter <scott@alfter.us>
 */

#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 = 0444,
		},
		.size = 1,
		.read = w1_f12_read_state,
	},
	{
		.attr = {
			.name = "output",
			.mode = 0664,
		},
		.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 <scott@alfter.us>");
MODULE_DESCRIPTION("w1 family 12 driver for DS2406 2 Pin IO");
MODULE_LICENSE("GPL");
Commit	Line	Data
40b0b3f8	1	// SPDX-License-Identifier: GPL-2.0-only
94859308 SA	2	/*
	3	* w1_ds2406.c - w1 family 12 (DS2406) driver
	4	* based on w1_ds2413.c by Mariusz Bialonczyk <manio@skyboo.net>
	5	*
	6	* Copyright (c) 2014 Scott Alfter <scott@alfter.us>
94859308 SA	7	*/
	8
	9	#include <linux/kernel.h>
	10	#include <linux/module.h>
	11	#include <linux/moduleparam.h>
	12	#include <linux/device.h>
	13	#include <linux/types.h>
	14	#include <linux/delay.h>
	15	#include <linux/slab.h>
	16	#include <linux/crc16.h>
	17
de0d6dbd AD	18	#include <linux/w1.h>
	19
	20	#define W1_FAMILY_DS2406 0x12
94859308	21
94859308 SA	22	#define W1_F12_FUNC_READ_STATUS 0xAA
	23	#define W1_F12_FUNC_WRITE_STATUS 0x55
	24
	25	static ssize_t w1_f12_read_state(
	26	struct file filp, struct kobject kobj,
	27	struct bin_attribute *bin_attr,
	28	char *buf, loff_t off, size_t count)
	29	{
ad9c36be	30	u8 w1_buf[6] = {W1_F12_FUNC_READ_STATUS, 7, 0, 0, 0, 0};
94859308	31	struct w1_slave *sl = kobj_to_w1_slave(kobj);
ad9c36be	32	u16 crc = 0;
94859308	33	int i;
ad9c36be	34	ssize_t rtnval = 1;
94859308 SA	35
	36	if (off != 0)
	37	return 0;
	38	if (!buf)
	39	return -EINVAL;
	40
	41	mutex_lock(&sl->master->bus_mutex);
	42
	43	if (w1_reset_select_slave(sl)) {
	44	mutex_unlock(&sl->master->bus_mutex);
	45	return -EIO;
	46	}
	47
	48	w1_write_block(sl->master, w1_buf, 3);
	49	w1_read_block(sl->master, w1_buf+3, 3);
ad9c36be KK	50	for (i = 0; i < 6; i++)
	51	crc = crc16_byte(crc, w1_buf[i]);
	52	if (crc == 0xb001) /* good read? */
	53	*buf = ((w1_buf[3]>>5)&3)\|0x30;
94859308	54	else
ad9c36be	55	rtnval = -EIO;
94859308 SA	56
	57	mutex_unlock(&sl->master->bus_mutex);
	58
	59	return rtnval;
	60	}
	61
	62	static ssize_t w1_f12_write_output(
	63	struct file filp, struct kobject kobj,
	64	struct bin_attribute *bin_attr,
	65	char *buf, loff_t off, size_t count)
	66	{
	67	struct w1_slave *sl = kobj_to_w1_slave(kobj);
ad9c36be KK	68	u8 w1_buf[6] = {W1_F12_FUNC_WRITE_STATUS, 7, 0, 0, 0, 0};
ad9c36be KK	69	u16 crc = 0;
94859308	70	int i;
ad9c36be	71	ssize_t rtnval = 1;
94859308 SA	72
	73	if (count != 1 \|\| off != 0)
	74	return -EFAULT;
	75
	76	mutex_lock(&sl->master->bus_mutex);
	77
	78	if (w1_reset_select_slave(sl)) {
	79	mutex_unlock(&sl->master->bus_mutex);
	80	return -EIO;
	81	}
	82
	83	w1_buf[3] = (((*buf)&3)<<5)\|0x1F;
	84	w1_write_block(sl->master, w1_buf, 4);
	85	w1_read_block(sl->master, w1_buf+4, 2);
ad9c36be KK	86	for (i = 0; i < 6; i++)
	87	crc = crc16_byte(crc, w1_buf[i]);
	88	if (crc == 0xb001) /* good read? */
94859308 SA	89	w1_write_8(sl->master, 0xFF);
94859308 SA	90	else
ad9c36be	91	rtnval = -EIO;
94859308 SA	92
	93	mutex_unlock(&sl->master->bus_mutex);
	94	return rtnval;
	95	}
	96
	97	#define NB_SYSFS_BIN_FILES 2
	98	static struct bin_attribute w1_f12_sysfs_bin_files[NB_SYSFS_BIN_FILES] = {
	99	{
	100	.attr = {
	101	.name = "state",
921e0f2f	102	.mode = 0444,
94859308 SA	103	},
	104	.size = 1,
	105	.read = w1_f12_read_state,
	106	},
	107	{
	108	.attr = {
	109	.name = "output",
921e0f2f	110	.mode = 0664,
94859308 SA	111	},
	112	.size = 1,
	113	.write = w1_f12_write_output,
	114	}
	115	};
	116
	117	static int w1_f12_add_slave(struct w1_slave *sl)
	118	{
	119	int err = 0;
	120	int i;
	121
	122	for (i = 0; i < NB_SYSFS_BIN_FILES && !err; ++i)
	123	err = sysfs_create_bin_file(
	124	&sl->dev.kobj,
	125	&(w1_f12_sysfs_bin_files[i]));
	126	if (err)
	127	while (--i >= 0)
	128	sysfs_remove_bin_file(&sl->dev.kobj,
	129	&(w1_f12_sysfs_bin_files[i]));
	130	return err;
	131	}
	132
	133	static void w1_f12_remove_slave(struct w1_slave *sl)
	134	{
	135	int i;
ad9c36be	136
94859308 SA	137	for (i = NB_SYSFS_BIN_FILES - 1; i >= 0; --i)
	138	sysfs_remove_bin_file(&sl->dev.kobj,
	139	&(w1_f12_sysfs_bin_files[i]));
	140	}
	141
57de2dfc	142	static const struct w1_family_ops w1_f12_fops = {
94859308 SA	143	.add_slave = w1_f12_add_slave,
	144	.remove_slave = w1_f12_remove_slave,
	145	};
	146
	147	static struct w1_family w1_family_12 = {
	148	.fid = W1_FAMILY_DS2406,
	149	.fops = &w1_f12_fops,
	150	};
939fc832	151	module_w1_family(w1_family_12);
50fa2951 AD	152
	153	MODULE_AUTHOR("Scott Alfter <scott@alfter.us>");
	154	MODULE_DESCRIPTION("w1 family 12 driver for DS2406 2 Pin IO");
	155	MODULE_LICENSE("GPL");