1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
2 | /* |
3 | * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net> |
4 | */ |
5 | |
6 | #ifndef __LINUX_W1_H |
7 | #define __LINUX_W1_H |
8 | |
9 | #include <linux/device.h> |
10 | |
11 | /** |
12 | * struct w1_reg_num - broken out slave device id |
13 | * |
14 | * @family: identifies the type of device |
15 | * @id: along with family is the unique device id |
16 | * @crc: checksum of the other bytes |
17 | */ |
18 | struct w1_reg_num { |
19 | #if defined(__LITTLE_ENDIAN_BITFIELD) |
20 | __u64 family:8, |
21 | id:48, |
22 | crc:8; |
23 | #elif defined(__BIG_ENDIAN_BITFIELD) |
24 | __u64 crc:8, |
25 | id:48, |
26 | family:8; |
27 | #else |
28 | #error "Please fix <asm/byteorder.h>" |
29 | #endif |
30 | }; |
31 | |
32 | #ifdef __KERNEL__ |
33 | |
34 | #define W1_MAXNAMELEN 32 |
35 | |
36 | #define W1_SEARCH 0xF0 |
37 | #define W1_ALARM_SEARCH 0xEC |
38 | #define W1_CONVERT_TEMP 0x44 |
39 | #define W1_SKIP_ROM 0xCC |
40 | #define W1_COPY_SCRATCHPAD 0x48 |
41 | #define W1_WRITE_SCRATCHPAD 0x4E |
42 | #define W1_READ_SCRATCHPAD 0xBE |
43 | #define W1_READ_ROM 0x33 |
44 | #define W1_READ_PSUPPLY 0xB4 |
45 | #define W1_MATCH_ROM 0x55 |
46 | #define W1_RESUME_CMD 0xA5 |
47 | |
48 | /** |
49 | * struct w1_slave - holds a single slave device on the bus |
50 | * |
51 | * @owner: Points to the one wire "wire" kernel module. |
52 | * @name: Device id is ascii. |
53 | * @w1_slave_entry: data for the linked list |
54 | * @reg_num: the slave id in binary |
55 | * @refcnt: reference count, delete when 0 |
56 | * @flags: bit flags for W1_SLAVE_ACTIVE W1_SLAVE_DETACH |
57 | * @ttl: decrement per search this slave isn't found, deatch at 0 |
58 | * @master: bus which this slave is on |
59 | * @family: module for device family type |
60 | * @family_data: pointer for use by the family module |
61 | * @dev: kernel device identifier |
62 | * @hwmon: pointer to hwmon device |
63 | * |
64 | */ |
65 | struct w1_slave { |
66 | struct module *owner; |
67 | unsigned char name[W1_MAXNAMELEN]; |
68 | struct list_head w1_slave_entry; |
69 | struct w1_reg_num reg_num; |
70 | atomic_t refcnt; |
71 | int ttl; |
72 | unsigned long flags; |
73 | |
74 | struct w1_master *master; |
75 | struct w1_family *family; |
76 | void *family_data; |
77 | struct device dev; |
78 | struct device *hwmon; |
79 | }; |
80 | |
81 | typedef void (*w1_slave_found_callback)(struct w1_master *, u64); |
82 | |
83 | /** |
84 | * struct w1_bus_master - operations available on a bus master |
85 | * |
86 | * @data: the first parameter in all the functions below |
87 | * |
88 | * @read_bit: Sample the line level @return the level read (0 or 1) |
89 | * |
90 | * @write_bit: Sets the line level |
91 | * |
92 | * @touch_bit: the lowest-level function for devices that really support the |
93 | * 1-wire protocol. |
94 | * touch_bit(0) = write-0 cycle |
95 | * touch_bit(1) = write-1 / read cycle |
96 | * @return the bit read (0 or 1) |
97 | * |
98 | * @read_byte: Reads a bytes. Same as 8 touch_bit(1) calls. |
99 | * @return the byte read |
100 | * |
101 | * @write_byte: Writes a byte. Same as 8 touch_bit(x) calls. |
102 | * |
103 | * @read_block: Same as a series of read_byte() calls |
104 | * @return the number of bytes read |
105 | * |
106 | * @write_block: Same as a series of write_byte() calls |
107 | * |
108 | * @triplet: Combines two reads and a smart write for ROM searches |
109 | * @return bit0=Id bit1=comp_id bit2=dir_taken |
110 | * |
111 | * @reset_bus: long write-0 with a read for the presence pulse detection |
112 | * @return -1=Error, 0=Device present, 1=No device present |
113 | * |
114 | * @set_pullup: Put out a strong pull-up pulse of the specified duration. |
115 | * @return -1=Error, 0=completed |
116 | * |
117 | * @search: Really nice hardware can handles the different types of ROM search |
118 | * w1_master* is passed to the slave found callback. |
119 | * u8 is search_type, W1_SEARCH or W1_ALARM_SEARCH |
120 | * |
121 | * @dev_id: Optional device id string, which w1 slaves could use for |
122 | * creating names, which then give a connection to the w1 master |
123 | * |
124 | * Note: read_bit and write_bit are very low level functions and should only |
125 | * be used with hardware that doesn't really support 1-wire operations, |
126 | * like a parallel/serial port. |
127 | * Either define read_bit and write_bit OR define, at minimum, touch_bit and |
128 | * reset_bus. |
129 | * |
130 | */ |
131 | struct w1_bus_master { |
132 | void *data; |
133 | |
134 | u8 (*read_bit)(void *); |
135 | |
136 | void (*write_bit)(void *, u8); |
137 | |
138 | u8 (*touch_bit)(void *, u8); |
139 | |
140 | u8 (*read_byte)(void *); |
141 | |
142 | void (*write_byte)(void *, u8); |
143 | |
144 | u8 (*read_block)(void *, u8 *, int); |
145 | |
146 | void (*write_block)(void *, const u8 *, int); |
147 | |
148 | u8 (*triplet)(void *, u8); |
149 | |
150 | u8 (*reset_bus)(void *); |
151 | |
152 | u8 (*set_pullup)(void *, int); |
153 | |
154 | void (*search)(void *, struct w1_master *, |
155 | u8, w1_slave_found_callback); |
156 | |
157 | char *dev_id; |
158 | }; |
159 | |
160 | /** |
161 | * enum w1_master_flags - bitfields used in w1_master.flags |
162 | * @W1_ABORT_SEARCH: abort searching early on shutdown |
163 | * @W1_WARN_MAX_COUNT: limit warning when the maximum count is reached |
164 | */ |
165 | enum w1_master_flags { |
166 | W1_ABORT_SEARCH = 0, |
167 | W1_WARN_MAX_COUNT = 1, |
168 | }; |
169 | |
170 | /** |
171 | * struct w1_master - one per bus master |
172 | * @w1_master_entry: master linked list |
173 | * @owner: module owner |
174 | * @name: dynamically allocate bus name |
175 | * @list_mutex: protect slist and async_list |
176 | * @slist: linked list of slaves |
177 | * @async_list: linked list of netlink commands to execute |
178 | * @max_slave_count: maximum number of slaves to search for at a time |
179 | * @slave_count: current number of slaves known |
180 | * @attempts: number of searches ran |
181 | * @slave_ttl: number of searches before a slave is timed out |
182 | * @initialized: prevent init/removal race conditions |
183 | * @id: w1 bus number |
184 | * @search_count: number of automatic searches to run, -1 unlimited |
185 | * @search_id: allows continuing a search |
186 | * @refcnt: reference count |
187 | * @priv: private data storage |
188 | * @enable_pullup: allows a strong pullup |
189 | * @pullup_duration: time for the next strong pullup |
190 | * @flags: one of w1_master_flags |
191 | * @thread: thread for bus search and netlink commands |
192 | * @mutex: protect most of w1_master |
193 | * @bus_mutex: pretect concurrent bus access |
194 | * @driver: sysfs driver |
195 | * @dev: sysfs device |
196 | * @bus_master: io operations available |
197 | * @seq: sequence number used for netlink broadcasts |
198 | */ |
199 | struct w1_master { |
200 | struct list_head w1_master_entry; |
201 | struct module *owner; |
202 | unsigned char name[W1_MAXNAMELEN]; |
203 | /* list_mutex protects just slist and async_list so slaves can be |
204 | * searched for and async commands added while the master has |
205 | * w1_master.mutex locked and is operating on the bus. |
206 | * lock order w1_mlock, w1_master.mutex, w1_master.list_mutex |
207 | */ |
208 | struct mutex list_mutex; |
209 | struct list_head slist; |
210 | struct list_head async_list; |
211 | int max_slave_count, slave_count; |
212 | unsigned long attempts; |
213 | int slave_ttl; |
214 | int initialized; |
215 | u32 id; |
216 | int search_count; |
217 | /* id to start searching on, to continue a search or 0 to restart */ |
218 | u64 search_id; |
219 | |
220 | atomic_t refcnt; |
221 | |
222 | void *priv; |
223 | |
224 | /** 5V strong pullup enabled flag, 1 enabled, zero disabled. */ |
225 | int enable_pullup; |
226 | /** 5V strong pullup duration in milliseconds, zero disabled. */ |
227 | int pullup_duration; |
228 | |
229 | long flags; |
230 | |
231 | struct task_struct *thread; |
232 | struct mutex mutex; |
233 | struct mutex bus_mutex; |
234 | |
235 | struct device_driver *driver; |
236 | struct device dev; |
237 | |
238 | struct w1_bus_master *bus_master; |
239 | |
240 | u32 seq; |
241 | }; |
242 | |
243 | int w1_add_master_device(struct w1_bus_master *master); |
244 | void w1_remove_master_device(struct w1_bus_master *master); |
245 | |
246 | /** |
247 | * struct w1_family_ops - operations for a family type |
248 | * @add_slave: add_slave |
249 | * @remove_slave: remove_slave |
250 | * @groups: sysfs group |
251 | * @chip_info: pointer to struct hwmon_chip_info |
252 | */ |
253 | struct w1_family_ops { |
254 | int (*add_slave)(struct w1_slave *sl); |
255 | void (*remove_slave)(struct w1_slave *sl); |
256 | const struct attribute_group **groups; |
257 | const struct hwmon_chip_info *chip_info; |
258 | }; |
259 | |
260 | /** |
261 | * struct w1_family - reference counted family structure. |
262 | * @family_entry: family linked list |
263 | * @fid: 8 bit family identifier |
264 | * @fops: operations for this family |
265 | * @of_match_table: open firmware match table |
266 | * @refcnt: reference counter |
267 | */ |
268 | struct w1_family { |
269 | struct list_head family_entry; |
270 | u8 fid; |
271 | |
272 | const struct w1_family_ops *fops; |
273 | |
274 | const struct of_device_id *of_match_table; |
275 | |
276 | atomic_t refcnt; |
277 | }; |
278 | |
279 | int w1_register_family(struct w1_family *family); |
280 | void w1_unregister_family(struct w1_family *family); |
281 | |
282 | /** |
283 | * module_w1_family() - Helper macro for registering a 1-Wire families |
284 | * @__w1_family: w1_family struct |
285 | * |
286 | * Helper macro for 1-Wire families which do not do anything special in module |
287 | * init/exit. This eliminates a lot of boilerplate. Each module may only |
288 | * use this macro once, and calling it replaces module_init() and module_exit() |
289 | */ |
290 | #define module_w1_family(__w1_family) \ |
291 | module_driver(__w1_family, w1_register_family, \ |
292 | w1_unregister_family) |
293 | |
294 | u8 w1_triplet(struct w1_master *dev, int bdir); |
295 | u8 w1_touch_bit(struct w1_master *dev, int bit); |
296 | void w1_write_8(struct w1_master *, u8); |
297 | u8 w1_read_8(struct w1_master *); |
298 | int w1_reset_bus(struct w1_master *); |
299 | u8 w1_calc_crc8(u8 *, int); |
300 | void w1_write_block(struct w1_master *, const u8 *, int); |
301 | void w1_touch_block(struct w1_master *, u8 *, int); |
302 | u8 w1_read_block(struct w1_master *, u8 *, int); |
303 | int w1_reset_select_slave(struct w1_slave *sl); |
304 | int w1_reset_resume_command(struct w1_master *); |
305 | void w1_next_pullup(struct w1_master *, int); |
306 | |
307 | static inline struct w1_slave* dev_to_w1_slave(struct device *dev) |
308 | { |
309 | return container_of(dev, struct w1_slave, dev); |
310 | } |
311 | |
312 | static inline struct w1_slave* kobj_to_w1_slave(struct kobject *kobj) |
313 | { |
314 | return dev_to_w1_slave(container_of(kobj, struct device, kobj)); |
315 | } |
316 | |
317 | static inline struct w1_master* dev_to_w1_master(struct device *dev) |
318 | { |
319 | return container_of(dev, struct w1_master, dev); |
320 | } |
321 | |
322 | #endif /* __KERNEL__ */ |
323 | |
324 | #endif /* __LINUX_W1_H */ |
325 | |