drivers/w1/w1.h

   1 /*
   2  *      w1.h
   3  *
   4  * Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
   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
  59 #define W1_SLAVE_ACTIVE         0
  60
  61 struct w1_slave
  62 {
  63         struct module           *owner;
  64         unsigned char           name[W1_MAXNAMELEN];
  65         struct list_head        w1_slave_entry;
  66         struct w1_reg_num       reg_num;
  67         atomic_t                refcnt;
  68         u8                      rom[9];
  69         u32                     flags;
  70         int                     ttl;
  71
  72         struct w1_master        *master;
  73         struct w1_family        *family;
  74         void                    *family_data;
  75         struct device           dev;
  76         struct completion       released;
  77 };
  78
  79 typedef void (*w1_slave_found_callback)(struct w1_master *, u64);
  80
  81
  82 /**
  83  * Note: read_bit and write_bit are very low level functions and should only
  84  * be used with hardware that doesn't really support 1-wire operations,
  85  * like a parallel/serial port.
  86  * Either define read_bit and write_bit OR define, at minimum, touch_bit and
  87  * reset_bus.
  88  */
  89 struct w1_bus_master
  90 {
  91         /** the first parameter in all the functions below */
  92         void            *data;
  93
  94         /**
  95          * Sample the line level
  96          * @return the level read (0 or 1)
  97          */
  98         u8              (*read_bit)(void *);
  99
 100         /** Sets the line level */
 101         void            (*write_bit)(void *, u8);
 102
 103         /**
 104          * touch_bit is the lowest-level function for devices that really
 105          * support the 1-wire protocol.
 106          * touch_bit(0) = write-0 cycle
 107          * touch_bit(1) = write-1 / read cycle
 108          * @return the bit read (0 or 1)
 109          */
 110         u8              (*touch_bit)(void *, u8);
 111
 112         /**
 113          * Reads a bytes. Same as 8 touch_bit(1) calls.
 114          * @return the byte read
 115          */
 116         u8              (*read_byte)(void *);
 117
 118         /**
 119          * Writes a byte. Same as 8 touch_bit(x) calls.
 120          */
 121         void            (*write_byte)(void *, u8);
 122
 123         /**
 124          * Same as a series of read_byte() calls
 125          * @return the number of bytes read
 126          */
 127         u8              (*read_block)(void *, u8 *, int);
 128
 129         /** Same as a series of write_byte() calls */
 130         void            (*write_block)(void *, const u8 *, int);
 131
 132         /**
 133          * Combines two reads and a smart write for ROM searches
 134          * @return bit0=Id bit1=comp_id bit2=dir_taken
 135          */
 136         u8              (*triplet)(void *, u8);
 137
 138         /**
 139          * long write-0 with a read for the presence pulse detection
 140          * @return -1=Error, 0=Device present, 1=No device present
 141          */
 142         u8              (*reset_bus)(void *);
 143
 144         /**
 145          * Put out a strong pull-up pulse of the specified duration.
 146          * @return -1=Error, 0=completed
 147          */
 148         u8              (*set_pullup)(void *, int);
 149
 150         /** Really nice hardware can handles the different types of ROM search
 151          *  w1_master* is passed to the slave found callback.
 152          */
 153         void            (*search)(void *, struct w1_master *,
 154                 u8, w1_slave_found_callback);
 155 };
 156
 157 struct w1_master
 158 {
 159         struct list_head        w1_master_entry;
 160         struct module           *owner;
 161         unsigned char           name[W1_MAXNAMELEN];
 162         struct list_head        slist;
 163         int                     max_slave_count, slave_count;
 164         unsigned long           attempts;
 165         int                     slave_ttl;
 166         int                     initialized;
 167         u32                     id;
 168         int                     search_count;
 169
 170         atomic_t                refcnt;
 171
 172         void                    *priv;
 173         int                     priv_size;
 174
 175         /** 5V strong pullup enabled flag, 1 enabled, zero disabled. */
 176         int                     enable_pullup;
 177         /** 5V strong pullup duration in milliseconds, zero disabled. */
 178         int                     pullup_duration;
 179
 180         struct task_struct      *thread;
 181         struct mutex            mutex;
 182
 183         struct device_driver    *driver;
 184         struct device           dev;
 185
 186         struct w1_bus_master    *bus_master;
 187
 188         u32                     seq;
 189 };
 190
 191 int w1_create_master_attributes(struct w1_master *);
 192 void w1_destroy_master_attributes(struct w1_master *master);
 193 void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb);
 194 void w1_search_devices(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb);
 195 struct w1_slave *w1_search_slave(struct w1_reg_num *id);
 196 void w1_search_process(struct w1_master *dev, u8 search_type);
 197 struct w1_master *w1_search_master_id(u32 id);
 198
 199 /* Disconnect and reconnect devices in the given family.  Used for finding
 200  * unclaimed devices after a family has been registered or releasing devices
 201  * after a family has been unregistered.  Set attach to 1 when a new family
 202  * has just been registered, to 0 when it has been unregistered.
 203  */
 204 void w1_reconnect_slaves(struct w1_family *f, int attach);
 205 void w1_slave_detach(struct w1_slave *sl);
 206
 207 u8 w1_triplet(struct w1_master *dev, int bdir);
 208 void w1_write_8(struct w1_master *, u8);
 209 u8 w1_read_8(struct w1_master *);
 210 int w1_reset_bus(struct w1_master *);
 211 u8 w1_calc_crc8(u8 *, int);
 212 void w1_write_block(struct w1_master *, const u8 *, int);
 213 void w1_touch_block(struct w1_master *, u8 *, int);
 214 u8 w1_read_block(struct w1_master *, u8 *, int);
 215 int w1_reset_select_slave(struct w1_slave *sl);
 216 void w1_next_pullup(struct w1_master *, int);
 217
 218 static inline struct w1_slave* dev_to_w1_slave(struct device *dev)
 219 {
 220         return container_of(dev, struct w1_slave, dev);
 221 }
 222
 223 static inline struct w1_slave* kobj_to_w1_slave(struct kobject *kobj)
 224 {
 225         return dev_to_w1_slave(container_of(kobj, struct device, kobj));
 226 }
 227
 228 static inline struct w1_master* dev_to_w1_master(struct device *dev)
 229 {
 230         return container_of(dev, struct w1_master, dev);
 231 }
 232
 233 extern struct device_driver w1_master_driver;
 234 extern struct device w1_master_device;
 235 extern int w1_max_slave_count;
 236 extern int w1_max_slave_ttl;
 237 extern struct list_head w1_masters;
 238 extern struct mutex w1_mlock;
 239
 240 extern int w1_process(void *);
 241
 242 #endif /* __KERNEL__ */
 243
 244 #endif /* __W1_H */