/*
 *      w1.h
 *
 * Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
 *
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#ifndef __W1_H
#define __W1_H

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__

#include <linux/completion.h>
#include <linux/device.h>
#include <linux/mutex.h>

#include "w1_family.h"

#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_READ_SCRATCHPAD      0xBE
#define W1_READ_ROM             0x33
#define W1_READ_PSUPPLY         0xB4
#define W1_MATCH_ROM            0x55

#define W1_SLAVE_ACTIVE         0

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;
        u8                      rom[9];
        u32                     flags;
        int                     ttl;

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

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


/**
 * 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
{
        /** the first parameter in all the functions below */
        void            *data;

        /**
         * Sample the line level
         * @return the level read (0 or 1)
         */
        u8              (*read_bit)(void *);

        /** Sets the line level */
        void            (*write_bit)(void *, u8);

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

        /**
         * Reads a bytes. Same as 8 touch_bit(1) calls.
         * @return the byte read
         */
        u8              (*read_byte)(void *);

        /**
         * Writes a byte. Same as 8 touch_bit(x) calls.
         */
        void            (*write_byte)(void *, u8);

        /**
         * Same as a series of read_byte() calls
         * @return the number of bytes read
         */
        u8              (*read_block)(void *, u8 *, int);

        /** Same as a series of write_byte() calls */
        void            (*write_block)(void *, const u8 *, int);

        /**
         * Combines two reads and a smart write for ROM searches
         * @return bit0=Id bit1=comp_id bit2=dir_taken
         */
        u8              (*triplet)(void *, u8);

        /**
         * long write-0 with a read for the presence pulse detection
         * @return -1=Error, 0=Device present, 1=No device present
         */
        u8              (*reset_bus)(void *);

        /**
         * Put out a strong pull-up pulse of the specified duration.
         * @return -1=Error, 0=completed
         */
        u8              (*set_pullup)(void *, int);

        /** Really nice hardware can handles the different types of ROM search
         *  w1_master* is passed to the slave found callback.
         */
        void            (*search)(void *, struct w1_master *,
                u8, w1_slave_found_callback);
};

struct w1_master
{
        struct list_head        w1_master_entry;
        struct module           *owner;
        unsigned char           name[W1_MAXNAMELEN];
        struct list_head        slist;
        int                     max_slave_count, slave_count;
        unsigned long           attempts;
        int                     slave_ttl;
        int                     initialized;
        u32                     id;
        int                     search_count;

        atomic_t                refcnt;

        void                    *priv;
        int                     priv_size;

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

        struct task_struct      *thread;
        struct mutex            mutex;

        struct device_driver    *driver;
        struct device           dev;

        struct w1_bus_master    *bus_master;

        u32                     seq;
};

int w1_create_master_attributes(struct w1_master *);
void w1_destroy_master_attributes(struct w1_master *master);
void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb);
void w1_search_devices(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb);
struct w1_slave *w1_search_slave(struct w1_reg_num *id);
void w1_search_process(struct w1_master *dev, u8 search_type);
struct w1_master *w1_search_master_id(u32 id);

/* Disconnect and reconnect devices in the given family.  Used for finding
 * unclaimed devices after a family has been registered or releasing devices
 * after a family has been unregistered.  Set attach to 1 when a new family
 * has just been registered, to 0 when it has been unregistered.
 */
void w1_reconnect_slaves(struct w1_family *f, int attach);
void w1_slave_detach(struct w1_slave *sl);

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);
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);
}

extern struct device_driver w1_master_driver;
extern struct device w1_master_device;
extern int w1_max_slave_count;
extern int w1_max_slave_ttl;
extern struct list_head w1_masters;
extern struct mutex w1_mlock;

extern int w1_process(void *);

#endif /* __KERNEL__ */

#endif /* __W1_H */