1/*
  2 *	w1.h
  3 *
  4 * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net>
  5 *
  6 *
  7 * This program is free software; you can redistribute it and/or modify
  8 * it under the terms of the GNU General Public License as published by
  9 * the Free Software Foundation; either version 2 of the License, or
 10 * (at your option) any later version.
 11 *
 12 * This program is distributed in the hope that it will be useful,
 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 15 * GNU General Public License for more details.
 16 *
 17 * You should have received a copy of the GNU General Public License
 18 * along with this program; if not, write to the Free Software
 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 20 */
 21
 22#ifndef __W1_H
 23#define __W1_H
 24
 25struct w1_reg_num
 26{
 27#if defined(__LITTLE_ENDIAN_BITFIELD)
 28	__u64	family:8,
 29		id:48,
 30		crc:8;
 31#elif defined(__BIG_ENDIAN_BITFIELD)
 32	__u64	crc:8,
 33		id:48,
 34		family:8;
 35#else
 36#error "Please fix <asm/byteorder.h>"
 37#endif
 38};
 39
 40#ifdef __KERNEL__
 41
 42#include <linux/completion.h>
 43#include <linux/device.h>
 44#include <linux/mutex.h>
 45
 46#include "w1_family.h"
 47
 48#define W1_MAXNAMELEN		32
 49
 50#define W1_SEARCH		0xF0
 51#define W1_ALARM_SEARCH		0xEC
 52#define W1_CONVERT_TEMP		0x44
 53#define W1_SKIP_ROM		0xCC
 54#define W1_READ_SCRATCHPAD	0xBE
 55#define W1_READ_ROM		0x33
 56#define W1_READ_PSUPPLY		0xB4
 57#define W1_MATCH_ROM		0x55
 58#define W1_RESUME_CMD		0xA5
 59
 60#define W1_SLAVE_ACTIVE		0
 61
 62struct w1_slave
 63{
 64	struct module		*owner;
 65	unsigned char		name[W1_MAXNAMELEN];
 66	struct list_head	w1_slave_entry;
 67	struct w1_reg_num	reg_num;
 68	atomic_t		refcnt;
 69	u8			rom[9];
 70	u32			flags;
 71	int			ttl;
 72
 73	struct w1_master	*master;
 74	struct w1_family	*family;
 75	void			*family_data;
 76	struct device		dev;
 77	struct completion	released;
 78};
 79
 80typedef void (*w1_slave_found_callback)(struct w1_master *, u64);
 81
 82
 83/**
 84 * Note: read_bit and write_bit are very low level functions and should only
 85 * be used with hardware that doesn't really support 1-wire operations,
 86 * like a parallel/serial port.
 87 * Either define read_bit and write_bit OR define, at minimum, touch_bit and
 88 * reset_bus.
 89 */
 90struct w1_bus_master
 91{
 92	/** the first parameter in all the functions below */
 93	void		*data;
 94
 95	/**
 96	 * Sample the line level
 97	 * @return the level read (0 or 1)
 98	 */
 99	u8		(*read_bit)(void *);
100
101	/** Sets the line level */
102	void		(*write_bit)(void *, u8);
103
104	/**
105	 * touch_bit is the lowest-level function for devices that really
106	 * support the 1-wire protocol.
107	 * touch_bit(0) = write-0 cycle
108	 * touch_bit(1) = write-1 / read cycle
109	 * @return the bit read (0 or 1)
110	 */
111	u8		(*touch_bit)(void *, u8);
112
113	/**
114	 * Reads a bytes. Same as 8 touch_bit(1) calls.
115	 * @return the byte read
116	 */
117	u8		(*read_byte)(void *);
118
119	/**
120	 * Writes a byte. Same as 8 touch_bit(x) calls.
121	 */
122	void		(*write_byte)(void *, u8);
123
124	/**
125	 * Same as a series of read_byte() calls
126	 * @return the number of bytes read
127	 */
128	u8		(*read_block)(void *, u8 *, int);
129
130	/** Same as a series of write_byte() calls */
131	void		(*write_block)(void *, const u8 *, int);
132
133	/**
134	 * Combines two reads and a smart write for ROM searches
135	 * @return bit0=Id bit1=comp_id bit2=dir_taken
136	 */
137	u8		(*triplet)(void *, u8);
138
139	/**
140	 * long write-0 with a read for the presence pulse detection
141	 * @return -1=Error, 0=Device present, 1=No device present
142	 */
143	u8		(*reset_bus)(void *);
144
145	/**
146	 * Put out a strong pull-up pulse of the specified duration.
147	 * @return -1=Error, 0=completed
148	 */
149	u8		(*set_pullup)(void *, int);
150
151	/** Really nice hardware can handles the different types of ROM search
152	 *  w1_master* is passed to the slave found callback.
153	 */
154	void		(*search)(void *, struct w1_master *,
155		u8, w1_slave_found_callback);
156};
157
158struct w1_master
159{
160	struct list_head	w1_master_entry;
161	struct module		*owner;
162	unsigned char		name[W1_MAXNAMELEN];
163	struct list_head	slist;
164	int			max_slave_count, slave_count;
165	unsigned long		attempts;
166	int			slave_ttl;
167	int			initialized;
168	u32			id;
169	int			search_count;
170
171	atomic_t		refcnt;
172
173	void			*priv;
174	int			priv_size;
175
176	/** 5V strong pullup enabled flag, 1 enabled, zero disabled. */
177	int			enable_pullup;
178	/** 5V strong pullup duration in milliseconds, zero disabled. */
179	int			pullup_duration;
180
181	struct task_struct	*thread;
182	struct mutex		mutex;
183
184	struct device_driver	*driver;
185	struct device		dev;
186
187	struct w1_bus_master	*bus_master;
188
189	u32			seq;
190};
191
192int w1_create_master_attributes(struct w1_master *);
193void w1_destroy_master_attributes(struct w1_master *master);
194void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb);
195void w1_search_devices(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb);
196struct w1_slave *w1_search_slave(struct w1_reg_num *id);
197void w1_slave_found(struct w1_master *dev, u64 rn);
198void w1_search_process_cb(struct w1_master *dev, u8 search_type,
199	w1_slave_found_callback cb);
200struct w1_master *w1_search_master_id(u32 id);
201
202/* Disconnect and reconnect devices in the given family.  Used for finding
203 * unclaimed devices after a family has been registered or releasing devices
204 * after a family has been unregistered.  Set attach to 1 when a new family
205 * has just been registered, to 0 when it has been unregistered.
206 */
207void w1_reconnect_slaves(struct w1_family *f, int attach);
208void w1_slave_detach(struct w1_slave *sl);
209
210u8 w1_triplet(struct w1_master *dev, int bdir);
211void w1_write_8(struct w1_master *, u8);
212u8 w1_read_8(struct w1_master *);
213int w1_reset_bus(struct w1_master *);
214u8 w1_calc_crc8(u8 *, int);
215void w1_write_block(struct w1_master *, const u8 *, int);
216void w1_touch_block(struct w1_master *, u8 *, int);
217u8 w1_read_block(struct w1_master *, u8 *, int);
218int w1_reset_select_slave(struct w1_slave *sl);
219int w1_reset_resume_command(struct w1_master *);
220void w1_next_pullup(struct w1_master *, int);
221
222static inline struct w1_slave* dev_to_w1_slave(struct device *dev)
223{
224	return container_of(dev, struct w1_slave, dev);
225}
226
227static inline struct w1_slave* kobj_to_w1_slave(struct kobject *kobj)
228{
229	return dev_to_w1_slave(container_of(kobj, struct device, kobj));
230}
231
232static inline struct w1_master* dev_to_w1_master(struct device *dev)
233{
234	return container_of(dev, struct w1_master, dev);
235}
236
237extern struct device_driver w1_master_driver;
238extern struct device w1_master_device;
239extern int w1_max_slave_count;
240extern int w1_max_slave_ttl;
241extern struct list_head w1_masters;
242extern struct mutex w1_mlock;
243
244extern int w1_process(void *);
245
246#endif /* __KERNEL__ */
247
248#endif /* __W1_H */