Home Home > GIT Browse
summaryrefslogtreecommitdiff
blob: 5b2972946dda5f9ad415f1eaeaab67743a5cc0f0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
/*
 * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms 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.
 */

#ifndef __LINUX_W1_H
#define __LINUX_W1_H

#include <linux/device.h>

/**
 * struct w1_reg_num - broken out slave device id
 *
 * @family: identifies the type of device
 * @id: along with family is the unique device id
 * @crc: checksum of the other bytes
 */
struct w1_reg_num {
#if defined(__LITTLE_ENDIAN_BITFIELD)
	__u64	family:8,
		id:48,
		crc:8;
#elif defined(__BIG_ENDIAN_BITFIELD)
	__u64	crc:8,
		id:48,
		family:8;
#else
#error "Please fix <asm/byteorder.h>"
#endif
};

#ifdef __KERNEL__

#define W1_MAXNAMELEN		32

#define W1_SEARCH		0xF0
#define W1_ALARM_SEARCH		0xEC
#define W1_CONVERT_TEMP		0x44
#define W1_SKIP_ROM		0xCC
#define W1_COPY_SCRATCHPAD	0x48
#define W1_WRITE_SCRATCHPAD	0x4E
#define W1_READ_SCRATCHPAD	0xBE
#define W1_READ_ROM		0x33
#define W1_READ_PSUPPLY		0xB4
#define W1_MATCH_ROM		0x55
#define W1_RESUME_CMD		0xA5

/**
 * struct w1_slave - holds a single slave device on the bus
 *
 * @owner: Points to the one wire "wire" kernel module.
 * @name: Device id is ascii.
 * @w1_slave_entry: data for the linked list
 * @reg_num: the slave id in binary
 * @refcnt: reference count, delete when 0
 * @flags: bit flags for W1_SLAVE_ACTIVE W1_SLAVE_DETACH
 * @ttl: decrement per search this slave isn't found, deatch at 0
 * @master: bus which this slave is on
 * @family: module for device family type
 * @family_data: pointer for use by the family module
 * @dev: kernel device identifier
 * @hwmon: pointer to hwmon device
 *
 */
struct w1_slave {
	struct module		*owner;
	unsigned char		name[W1_MAXNAMELEN];
	struct list_head	w1_slave_entry;
	struct w1_reg_num	reg_num;
	atomic_t		refcnt;
	int			ttl;
	unsigned long		flags;

	struct w1_master	*master;
	struct w1_family	*family;
	void			*family_data;
	struct device		dev;
	struct device		*hwmon;
};

typedef void (*w1_slave_found_callback)(struct w1_master *, u64);

/**
 * struct w1_bus_master - operations available on a bus master
 *
 * @data: the first parameter in all the functions below
 *
 * @read_bit: Sample the line level @return the level read (0 or 1)
 *
 * @write_bit: Sets the line level
 *
 * @touch_bit: the lowest-level function for devices that really support the
 * 1-wire protocol.
 * touch_bit(0) = write-0 cycle
 * touch_bit(1) = write-1 / read cycle
 * @return the bit read (0 or 1)
 *
 * @read_byte: Reads a bytes. Same as 8 touch_bit(1) calls.
 * @return the byte read
 *
 * @write_byte: Writes a byte. Same as 8 touch_bit(x) calls.
 *
 * @read_block: Same as a series of read_byte() calls
 * @return the number of bytes read
 *
 * @write_block: Same as a series of write_byte() calls
 *
 * @triplet: Combines two reads and a smart write for ROM searches
 * @return bit0=Id bit1=comp_id bit2=dir_taken
 *
 * @reset_bus: long write-0 with a read for the presence pulse detection
 * @return -1=Error, 0=Device present, 1=No device present
 *
 * @set_pullup: Put out a strong pull-up pulse of the specified duration.
 * @return -1=Error, 0=completed
 *
 * @search: Really nice hardware can handles the different types of ROM search
 * w1_master* is passed to the slave found callback.
 * u8 is search_type, W1_SEARCH or W1_ALARM_SEARCH
 *
 * Note: read_bit and write_bit are very low level functions and should only
 * be used with hardware that doesn't really support 1-wire operations,
 * like a parallel/serial port.
 * Either define read_bit and write_bit OR define, at minimum, touch_bit and
 * reset_bus.
 *
 */
struct w1_bus_master {
	void		*data;

	u8		(*read_bit)(void *);

	void		(*write_bit)(void *, u8);

	u8		(*touch_bit)(void *, u8);

	u8		(*read_byte)(void *);

	void		(*write_byte)(void *, u8);

	u8		(*read_block)(void *, u8 *, int);

	void		(*write_block)(void *, const u8 *, int);

	u8		(*triplet)(void *, u8);

	u8		(*reset_bus)(void *);

	u8		(*set_pullup)(void *, int);

	void		(*search)(void *, struct w1_master *,
		u8, w1_slave_found_callback);
};

/**
 * enum w1_master_flags - bitfields used in w1_master.flags
 * @W1_ABORT_SEARCH: abort searching early on shutdown
 * @W1_WARN_MAX_COUNT: limit warning when the maximum count is reached
 */
enum w1_master_flags {
	W1_ABORT_SEARCH = 0,
	W1_WARN_MAX_COUNT = 1,
};

/**
 * struct w1_master - one per bus master
 * @w1_master_entry:	master linked list
 * @owner:		module owner
 * @name:		dynamically allocate bus name
 * @list_mutex:		protect slist and async_list
 * @slist:		linked list of slaves
 * @async_list:		linked list of netlink commands to execute
 * @max_slave_count:	maximum number of slaves to search for at a time
 * @slave_count:	current number of slaves known
 * @attempts:		number of searches ran
 * @slave_ttl:		number of searches before a slave is timed out
 * @initialized:	prevent init/removal race conditions
 * @id:			w1 bus number
 * @search_count:	number of automatic searches to run, -1 unlimited
 * @search_id:		allows continuing a search
 * @refcnt:		reference count
 * @priv:		private data storage
 * @enable_pullup:	allows a strong pullup
 * @pullup_duration:	time for the next strong pullup
 * @flags:		one of w1_master_flags
 * @thread:		thread for bus search and netlink commands
 * @mutex:		protect most of w1_master
 * @bus_mutex:		pretect concurrent bus access
 * @driver:		sysfs driver
 * @dev:		sysfs device
 * @bus_master:		io operations available
 * @seq:		sequence number used for netlink broadcasts
 */
struct w1_master {
	struct list_head	w1_master_entry;
	struct module		*owner;
	unsigned char		name[W1_MAXNAMELEN];
	/* list_mutex protects just slist and async_list so slaves can be
	 * searched for and async commands added while the master has
	 * w1_master.mutex locked and is operating on the bus.
	 * lock order w1_mlock, w1_master.mutex, w1_master.list_mutex
	 */
	struct mutex		list_mutex;
	struct list_head	slist;
	struct list_head	async_list;
	int			max_slave_count, slave_count;
	unsigned long		attempts;
	int			slave_ttl;
	int			initialized;
	u32			id;
	int			search_count;
	/* id to start searching on, to continue a search or 0 to restart */
	u64			search_id;

	atomic_t		refcnt;

	void			*priv;

	/** 5V strong pullup enabled flag, 1 enabled, zero disabled. */
	int			enable_pullup;
	/** 5V strong pullup duration in milliseconds, zero disabled. */
	int			pullup_duration;

	long			flags;

	struct task_struct	*thread;
	struct mutex		mutex;
	struct mutex		bus_mutex;

	struct device_driver	*driver;
	struct device		dev;

	struct w1_bus_master	*bus_master;

	u32			seq;
};

int w1_add_master_device(struct w1_bus_master *master);
void w1_remove_master_device(struct w1_bus_master *master);

/**
 * struct w1_family_ops - operations for a family type
 * @add_slave: add_slave
 * @remove_slave: remove_slave
 * @groups: sysfs group
 * @chip_info: pointer to struct hwmon_chip_info
 */
struct w1_family_ops {
	int  (*add_slave)(struct w1_slave *sl);
	void (*remove_slave)(struct w1_slave *sl);
	const struct attribute_group **groups;
	const struct hwmon_chip_info *chip_info;
};

/**
 * struct w1_family - reference counted family structure.
 * @family_entry:	family linked list
 * @fid:		8 bit family identifier
 * @fops:		operations for this family
 * @refcnt:		reference counter
 */
struct w1_family {
	struct list_head	family_entry;
	u8			fid;

	struct w1_family_ops	*fops;

	atomic_t		refcnt;
};

int w1_register_family(struct w1_family *family);
void w1_unregister_family(struct w1_family *family);

/**
 * module_w1_driver() - Helper macro for registering a 1-Wire families
 * @__w1_family: w1_family struct
 *
 * Helper macro for 1-Wire families which do not do anything special in module
 * init/exit. This eliminates a lot of boilerplate. Each module may only
 * use this macro once, and calling it replaces module_init() and module_exit()
 */
#define module_w1_family(__w1_family) \
	module_driver(__w1_family, w1_register_family, \
			w1_unregister_family)

u8 w1_triplet(struct w1_master *dev, int bdir);
void w1_write_8(struct w1_master *, u8);
u8 w1_read_8(struct w1_master *);
int w1_reset_bus(struct w1_master *);
u8 w1_calc_crc8(u8 *, int);
void w1_write_block(struct w1_master *, const u8 *, int);
void w1_touch_block(struct w1_master *, u8 *, int);
u8 w1_read_block(struct w1_master *, u8 *, int);
int w1_reset_select_slave(struct w1_slave *sl);
int w1_reset_resume_command(struct w1_master *);
void w1_next_pullup(struct w1_master *, int);

static inline struct w1_slave* dev_to_w1_slave(struct device *dev)
{
	return container_of(dev, struct w1_slave, dev);
}

static inline struct w1_slave* kobj_to_w1_slave(struct kobject *kobj)
{
	return dev_to_w1_slave(container_of(kobj, struct device, kobj));
}

static inline struct w1_master* dev_to_w1_master(struct device *dev)
{
	return container_of(dev, struct w1_master, dev);
}

#endif /* __KERNEL__ */

#endif /* __LINUX_W1_H */