drivers/w1/w1.h

   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         struct mutex            mutex;
  79 };
  80
  81 typedef void (*w1_slave_found_callback)(struct w1_master *, u64);
  82
  83
  84 /**
  85  * Note: read_bit and write_bit are very low level functions and should only
  86  * be used with hardware that doesn't really support 1-wire operations,
  87  * like a parallel/serial port.
  88  * Either define read_bit and write_bit OR define, at minimum, touch_bit and
  89  * reset_bus.
  90  */
  91 struct w1_bus_master
  92 {
  93         /** the first parameter in all the functions below */
  94         void            *data;
  95
  96         /**
  97          * Sample the line level
  98          * @return the level read (0 or 1)
  99          */
 100         u8              (*read_bit)(void *);
 101
 102         /** Sets the line level */
 103         void            (*write_bit)(void *, u8);
 104
 105         /**
 106          * touch_bit is the lowest-level function for devices that really
 107          * support the 1-wire protocol.
 108          * touch_bit(0) = write-0 cycle
 109          * touch_bit(1) = write-1 / read cycle
 110          * @return the bit read (0 or 1)
 111          */
 112         u8              (*touch_bit)(void *, u8);
 113
 114         /**
 115          * Reads a bytes. Same as 8 touch_bit(1) calls.
 116          * @return the byte read
 117          */
 118         u8              (*read_byte)(void *);
 119
 120         /**
 121          * Writes a byte. Same as 8 touch_bit(x) calls.
 122          */
 123         void            (*write_byte)(void *, u8);
 124
 125         /**
 126          * Same as a series of read_byte() calls
 127          * @return the number of bytes read
 128          */
 129         u8              (*read_block)(void *, u8 *, int);
 130
 131         /** Same as a series of write_byte() calls */
 132         void            (*write_block)(void *, const u8 *, int);
 133
 134         /**
 135          * Combines two reads and a smart write for ROM searches
 136          * @return bit0=Id bit1=comp_id bit2=dir_taken
 137          */
 138         u8              (*triplet)(void *, u8);
 139
 140         /**
 141          * long write-0 with a read for the presence pulse detection
 142          * @return -1=Error, 0=Device present, 1=No device present
 143          */
 144         u8              (*reset_bus)(void *);
 145
 146         /**
 147          * Put out a strong pull-up pulse of the specified duration.
 148          * @return -1=Error, 0=completed
 149          */
 150         u8              (*set_pullup)(void *, int);
 151
 152         /** Really nice hardware can handles the different types of ROM search
 153          *  w1_master* is passed to the slave found callback.
 154          */
 155         void            (*search)(void *, struct w1_master *,
 156                 u8, w1_slave_found_callback);
 157 };
 158
 159 struct w1_master
 160 {
 161         struct list_head        w1_master_entry;
 162         struct module           *owner;
 163         unsigned char           name[W1_MAXNAMELEN];
 164         struct list_head        slist;
 165         int                     max_slave_count, slave_count;
 166         unsigned long           attempts;
 167         int                     slave_ttl;
 168         int                     initialized;
 169         u32                     id;
 170         int                     search_count;
 171
 172         atomic_t                refcnt;
 173
 174         void                    *priv;
 175         int                     priv_size;
 176
 177         /** 5V strong pullup enabled flag, 1 enabled, zero disabled. */
 178         int                     enable_pullup;
 179         /** 5V strong pullup duration in milliseconds, zero disabled. */
 180         int                     pullup_duration;
 181
 182         struct task_struct      *thread;
 183         struct mutex            mutex;
 184
 185         struct device_driver    *driver;
 186         struct device           dev;
 187
 188         struct w1_bus_master    *bus_master;
 189
 190         u32                     seq;
 191 };
 192
 193 int w1_create_master_attributes(struct w1_master *);
 194 void w1_destroy_master_attributes(struct w1_master *master);
 195 void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb);
 196 void w1_search_devices(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb);
 197 struct w1_slave *w1_search_slave(struct w1_reg_num *id);
 198 void w1_slave_found(struct w1_master *dev, u64 rn);
 199 void w1_search_process_cb(struct w1_master *dev, u8 search_type,
 200         w1_slave_found_callback cb);
 201 struct w1_master *w1_search_master_id(u32 id);
 202
 203 /* Disconnect and reconnect devices in the given family.  Used for finding
 204  * unclaimed devices after a family has been registered or releasing devices
 205  * after a family has been unregistered.  Set attach to 1 when a new family
 206  * has just been registered, to 0 when it has been unregistered.
 207  */
 208 void w1_reconnect_slaves(struct w1_family *f, int attach);
 209 void w1_slave_detach(struct w1_slave *sl);
 210
 211 u8 w1_triplet(struct w1_master *dev, int bdir);
 212 void w1_write_8(struct w1_master *, u8);
 213 u8 w1_read_8(struct w1_master *);
 214 int w1_reset_bus(struct w1_master *);
 215 u8 w1_calc_crc8(u8 *, int);
 216 void w1_write_block(struct w1_master *, const u8 *, int);
 217 void w1_touch_block(struct w1_master *, u8 *, int);
 218 u8 w1_read_block(struct w1_master *, u8 *, int);
 219 int w1_reset_select_slave(struct w1_slave *sl);
 220 int w1_reset_resume_command(struct w1_master *);
 221 void w1_next_pullup(struct w1_master *, int);
 222
 223 static inline struct w1_slave* dev_to_w1_slave(struct device *dev)
 224 {
 225         return container_of(dev, struct w1_slave, dev);
 226 }
 227
 228 static inline struct w1_slave* kobj_to_w1_slave(struct kobject *kobj)
 229 {
 230         return dev_to_w1_slave(container_of(kobj, struct device, kobj));
 231 }
 232
 233 static inline struct w1_master* dev_to_w1_master(struct device *dev)
 234 {
 235         return container_of(dev, struct w1_master, dev);
 236 }
 237
 238 extern struct device_driver w1_master_driver;
 239 extern struct device w1_master_device;
 240 extern int w1_max_slave_count;
 241 extern int w1_max_slave_ttl;
 242 extern struct list_head w1_masters;
 243 extern struct mutex w1_mlock;
 244
 245 extern int w1_process(void *);
 246
 247 #endif /* __KERNEL__ */
 248
 249 #endif /* __W1_H */