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
25 struct 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
62 struct 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
80 typedef 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 */
90 struct 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
158 struct 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
192 int w1_create_master_attributes(struct w1_master *);
193 void w1_destroy_master_attributes(struct w1_master *master);
194 void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb);
195 void w1_search_devices(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb);
196 struct w1_slave *w1_search_slave(struct w1_reg_num *id);
197 void w1_slave_found(struct w1_master *dev, u64 rn);
198 void w1_search_process_cb(struct w1_master *dev, u8 search_type,
199 w1_slave_found_callback cb);
200 struct 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 */
207 void w1_reconnect_slaves(struct w1_family *f, int attach);
208 void w1_slave_detach(struct w1_slave *sl);
209
210 u8 w1_triplet(struct w1_master *dev, int bdir);
211 void w1_write_8(struct w1_master *, u8);
212 u8 w1_read_8(struct w1_master *);
213 int w1_reset_bus(struct w1_master *);
214 u8 w1_calc_crc8(u8 *, int);
215 void w1_write_block(struct w1_master *, const u8 *, int);
216 void w1_touch_block(struct w1_master *, u8 *, int);
217 u8 w1_read_block(struct w1_master *, u8 *, int);
218 int w1_reset_select_slave(struct w1_slave *sl);
219 int w1_reset_resume_command(struct w1_master *);
220 void w1_next_pullup(struct w1_master *, int);
221
dev_to_w1_slave(struct device * dev)222 static inline struct w1_slave* dev_to_w1_slave(struct device *dev)
223 {
224 return container_of(dev, struct w1_slave, dev);
225 }
226
kobj_to_w1_slave(struct kobject * kobj)227 static 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
dev_to_w1_master(struct device * dev)232 static inline struct w1_master* dev_to_w1_master(struct device *dev)
233 {
234 return container_of(dev, struct w1_master, dev);
235 }
236
237 extern struct device_driver w1_master_driver;
238 extern struct device w1_master_device;
239 extern int w1_max_slave_count;
240 extern int w1_max_slave_ttl;
241 extern struct list_head w1_masters;
242 extern struct mutex w1_mlock;
243
244 extern int w1_process(void *);
245
246 #endif /* __KERNEL__ */
247
248 #endif /* __W1_H */
249