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/* ------------------------------------------------------------------------- */
/*                                                                           */
/* i2c.h - definitions for the i2c-bus interface                             */
/*                                                                           */
/* ------------------------------------------------------------------------- */
/*   Copyright (C) 1995-2000 Simon G. Vogl

    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., 675 Mass Ave, Cambridge, MA 02139, USA.                */

/* ------------------------------------------------------------------------- */

/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and
   Frodo Looijaard <frodol@dds.nl> */


/* $Id: i2c.h,v 1.1 2003-05-22 10:25:25 giacomo Exp $ */

#ifndef I2C_H
#define I2C_H

#define I2C_DATE "20010830"
#define I2C_VERSION "2.6.1"

#include "drivers/i2c-id.h"     /* id values of adapters et. al.        */
#include <sys/types.h>
#include "drivers/compbttv.h"

struct i2c_msg;

/* --- General options ------------------------------------------------ */

#define I2C_ALGO_MAX    4               /* control memory consumption   */
#define I2C_ADAP_MAX    16
#define I2C_DRIVER_MAX  16
#define I2C_CLIENT_MAX  32
#define I2C_DUMMY_MAX 4

struct i2c_algorithm;
struct i2c_adapter;
struct i2c_client;
struct i2c_driver;
struct i2c_client_address_data;
union i2c_smbus_data;


/*
 * The master routines are the ones normally used to transmit data to devices
 * on a bus (or read from them). Apart from two basic transfer functions to
 * transmit one message at a time, a more complex version can be used to
 * transmit an arbitrary number of messages without interruption.
 */

extern int i2c_master_send(struct i2c_client *,const char* ,int);
extern int i2c_master_recv(struct i2c_client *,char* ,int);

/* Transfer num messages.
 */

extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg msg[],int num);

/*
 * Some adapter types (i.e. PCF 8584 based ones) may support slave behaviuor.
 * This is not tested/implemented yet and will change in the future.
 */

extern int i2c_slave_send(struct i2c_client *,char*,int);
extern int i2c_slave_recv(struct i2c_client *,char*,int);



/* This is the very generalized SMBus access routine. You probably do not
   want to use this, though; one of the functions below may be much easier,
   and probably just as fast.
   Note that we use i2c_adapter here, because you do not need a specific
   smbus adapter to call this function. */

extern __s32 i2c_smbus_xfer (struct i2c_adapter * adapter, __u16 addr,
                           unsigned short flags,
                           char read_write, __u8 command, int size,
                           union i2c_smbus_data * data);

/* Now follow the 'nice' access routines. These also document the calling
   conventions of smbus_access. */


extern __s32 i2c_smbus_write_quick(struct i2c_client * client, __u8 value);
extern __s32 i2c_smbus_read_byte(struct i2c_client * client);
extern __s32 i2c_smbus_write_byte(struct i2c_client * client, __u8 value);
extern __s32 i2c_smbus_read_byte_data(struct i2c_client * client, __u8 command);
extern __s32 i2c_smbus_write_byte_data(struct i2c_client * client,
                                     __u8 command, __u8 value);
extern __s32 i2c_smbus_read_word_data(struct i2c_client * client, __u8 command);
extern __s32 i2c_smbus_write_word_data(struct i2c_client * client,
                                     __u8 command, __u16 value);
extern __s32 i2c_smbus_process_call(struct i2c_client * client,
                                  __u8 command, __u16 value);
/* Returns the number of read bytes */
extern __s32 i2c_smbus_read_block_data(struct i2c_client * client,
                                     __u8 command, __u8 *values);
extern __s32 i2c_smbus_write_block_data(struct i2c_client * client,
                                      __u8 command, __u8 length,
                                      __u8 *values);
extern __s32 i2c_smbus_write_i2c_block_data(struct i2c_client * client,
                                          __u8 command, __u8 length,
                                          __u8 *values);


/*
 * A driver is capable of handling one or more physical devices present on
 * I2C adapters. This information is used to inform the driver of adapter
 * events.
 */


struct i2c_driver {
        char name[32];
        int id;
        unsigned int flags;             /* div., see below              */

        /* Notifies the driver that a new bus has appeared. This routine
         * can be used by the driver to test if the bus meets its conditions
         * & seek for the presence of the chip(s) it supports. If found, it
         * registers the client(s) that are on the bus to the i2c admin. via
         * i2c_attach_client.
         */

        int (*attach_adapter)(struct i2c_adapter *);

        /* tells the driver that a client is about to be deleted & gives it
         * the chance to remove its private data. Also, if the client struct
         * has been dynamically allocated by the driver in the function above,
         * it must be freed here.
         */

        int (*detach_client)(struct i2c_client *);
       
        /* a ioctl like command that can be used to perform specific functions
         * with the device.
         */

        int (*command)(struct i2c_client *client,unsigned int cmd, void *arg);
       
        /* These two are mainly used for bookkeeping & dynamic unloading of
         * kernel modules. inc_use tells the driver that a client is being  
         * used by another module & that it should increase its ref. counter.
         * dec_use is the inverse operation.
         * NB: Make sure you have no circular dependencies, or else you get a
         * deadlock when trying to unload the modules.
        * You should use the i2c_{inc,dec}_use_client functions instead of
        * calling this function directly.
         */

        void (*inc_use)(struct i2c_client *client);
        void (*dec_use)(struct i2c_client *client);
};

/*
 * i2c_client identifies a single device (i.e. chip) that is connected to an
 * i2c bus. The behaviour is defined by the routines of the driver. This
 * function is mainly used for lookup & other admin. functions.
 */

struct i2c_client {
        char name[32];
        int id;
        unsigned int flags;             /* div., see below              */
        unsigned int addr;              /* chip address - NOTE: 7bit    */
                                        /* addresses are stored in the  */
                                        /* _LOWER_ 7 bits of this char  */
        /* addr: unsigned int to make lm_sensors i2c-isa adapter work
          more cleanly. It does not take any more memory space, due to
          alignment considerations */

        struct i2c_adapter *adapter;    /* the adapter we sit on        */
        struct i2c_driver *driver;      /* and our access routines      */
        void *data;                     /* for the clients              */
        int usage_count;                /* How many accesses currently  */
                                        /* to the client                */
};


/*
 * The following structs are for those who like to implement new bus drivers:
 * i2c_algorithm is the interface to a class of hardware solutions which can
 * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584
 * to name two of the most common.
 */

struct i2c_algorithm {
        char name[32];                          /* textual description  */
        unsigned int id;

        /* If an adapter algorithm can't to I2C-level access, set master_xfer
           to NULL. If an adapter algorithm can do SMBus access, set
           smbus_xfer. If set to NULL, the SMBus protocol is simulated
           using common I2C messages */

        int (*master_xfer)(struct i2c_adapter *adap,struct i2c_msg msgs[],
                           int num);
        int (*smbus_xfer) (struct i2c_adapter *adap, __u16 addr,
                           unsigned short flags, char read_write,
                           __u8 command, int size, union i2c_smbus_data * data);

        /* --- these optional/future use for some adapter types.*/
        int (*slave_send)(struct i2c_adapter *,char*,int);
        int (*slave_recv)(struct i2c_adapter *,char*,int);

        /* --- ioctl like call to set div. parameters. */
        int (*algo_control)(struct i2c_adapter *, unsigned int, unsigned long);

        /* To determine what the adapter supports */
        __u32 (*functionality) (struct i2c_adapter *);
};

/*
 * i2c_adapter is the structure used to identify a physical i2c bus along
 * with the access algorithms necessary to access it.
 */

struct i2c_adapter {
        char name[32];  /* some useful name to identify the adapter     */
        unsigned int id;/* == is algo->id | hwdep.struct->id,           */
                        /* for registered values see below              */
        struct i2c_algorithm *algo;/* the algorithm to access the bus   */
        void *algo_data;

        /* --- These may be NULL, but should increase the module use count */
        void (*inc_use)(struct i2c_adapter *);
        void (*dec_use)(struct i2c_adapter *);

        /* --- administration stuff. */
        int (*client_register)(struct i2c_client *);
        int (*client_unregister)(struct i2c_client *);

        void *data;     /* private data for the adapter                 */
                        /* some data fields that are used by all types  */
                        /* these data fields are readonly to the public */
                        /* and can be set via the i2c_ioctl call        */

                        /* data fields that are valid for all devices   */
        unsigned int flags;/* flags specifying div. data                */

        struct i2c_client *clients[I2C_CLIENT_MAX];
        int client_count;

        int timeout;
        int retries;

};

/*flags for the driver struct: */
#define I2C_DF_NOTIFY   0x01            /* notify on bus (de/a)ttaches  */
#define I2C_DF_DUMMY    0x02            /* do not connect any clients */

/*flags for the client struct: */
#define I2C_CLIENT_ALLOW_USE            0x01    /* Client allows access */
#define I2C_CLIENT_ALLOW_MULTIPLE_USE   0x02    /* Allow multiple access-locks */
                                                /* on an i2c_client */

/* i2c_client_address_data is the struct for holding default client
 * addresses for a driver and for the parameters supplied on the
 * command line
 */

struct i2c_client_address_data {
        unsigned short *normal_i2c;
        unsigned short *normal_i2c_range;
        unsigned short *probe;
        unsigned short *probe_range;
        unsigned short *ignore;
        unsigned short *ignore_range;
        unsigned short *force;
};

/* Internal numbers to terminate lists */
#define I2C_CLIENT_END 0xfffe

/* The numbers to use to set I2C bus address */
#define ANY_I2C_BUS 0xffff

/* The length of the option lists */
#define I2C_CLIENT_MAX_OPTS 48


/* ----- functions exported by i2c.o */

/* administration...
 */

extern int i2c_add_adapter(struct i2c_adapter *);
extern int i2c_del_adapter(struct i2c_adapter *);

extern int i2c_add_driver(struct i2c_driver *);
extern int i2c_del_driver(struct i2c_driver *);

extern int i2c_attach_client(struct i2c_client *);
extern int i2c_detach_client(struct i2c_client *);

/* Only call these if you grab a resource that makes unloading the
   client and the adapter it is on completely impossible. Like when a
   /proc directory is entered. */

extern void i2c_inc_use_client(struct i2c_client *);
extern void i2c_dec_use_client(struct i2c_client *);

/* New function: This is to get an i2c_client-struct for controlling the
   client either by using i2c_control-function or having the
   client-module export functions that can be used with the i2c_client
   -struct. */

extern struct i2c_client *i2c_get_client(int driver_id, int adapter_id,
                                        struct i2c_client *prev);

/* Should be used with new function
   extern struct i2c_client *i2c_get_client(int,int,struct i2c_client *);
   to make sure that client-struct is valid and that it is okay to access
   the i2c-client.
   returns -EACCES if client doesn't allow use (default)
   returns -EBUSY if client doesn't allow multiple use (default) and
   usage_count >0 */

extern int i2c_use_client(struct i2c_client *);
extern int i2c_release_client(struct i2c_client *);

/* returns -EBUSY if address has been taken, 0 if not. Note that the only
   other place at which this is called is within i2c_attach_client; so
   you can cheat by simply not registering. Not recommended, of course! */

extern int i2c_check_addr (struct i2c_adapter *adapter, int addr);

/* Detect function. It iterates over all possible addresses itself.
 * It will only call found_proc if some client is connected at the
 * specific address (unless a 'force' matched);
 */

typedef int i2c_client_found_addr_proc (struct i2c_adapter *adapter,
                                     int addr, unsigned short flags,int kind);

extern int i2c_probe(struct i2c_adapter *adapter,
                struct i2c_client_address_data *address_data,
                i2c_client_found_addr_proc *found_proc);

/* An ioctl like call to set div. parameters of the adapter.
 */

extern int i2c_control(struct i2c_client *,unsigned int, unsigned long);

/* This call returns a unique low identifier for each registered adapter,
 * or -1 if the adapter was not registered.
 */

extern int i2c_adapter_id(struct i2c_adapter *adap);



/* Return the functionality mask */
extern __u32 i2c_get_functionality (struct i2c_adapter *adap);

/* Return 1 if adapter supports everything we need, 0 if not. */
extern int i2c_check_functionality (struct i2c_adapter *adap, __u32 func);

/*
 * I2C Message - used for pure i2c transaction, also from /dev interface
 */

struct i2c_msg {
        __u16 addr;     /* slave address                        */
        unsigned short flags;          
#define I2C_M_TEN       0x10    /* we have a ten bit chip address       */
#define I2C_M_RD        0x01
#define I2C_M_NOSTART   0x4000
#define I2C_M_REV_DIR_ADDR      0x2000
        short len;              /* msg length                           */
        char *buf;              /* pointer to msg data                  */
};

/* To determine what functionality is present */

#define I2C_FUNC_I2C                    0x00000001
#define I2C_FUNC_10BIT_ADDR             0x00000002
#define I2C_FUNC_PROTOCOL_MANGLING      0x00000004 /* I2C_M_{REV_DIR_ADDR,NOSTART} */
#define I2C_FUNC_SMBUS_QUICK            0x00010000
#define I2C_FUNC_SMBUS_READ_BYTE        0x00020000
#define I2C_FUNC_SMBUS_WRITE_BYTE       0x00040000
#define I2C_FUNC_SMBUS_READ_BYTE_DATA   0x00080000
#define I2C_FUNC_SMBUS_WRITE_BYTE_DATA  0x00100000
#define I2C_FUNC_SMBUS_READ_WORD_DATA   0x00200000
#define I2C_FUNC_SMBUS_WRITE_WORD_DATA  0x00400000
#define I2C_FUNC_SMBUS_PROC_CALL        0x00800000
#define I2C_FUNC_SMBUS_READ_BLOCK_DATA  0x01000000
#define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
#define I2C_FUNC_SMBUS_READ_I2C_BLOCK   0x04000000 /* New I2C-like block */
#define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK  0x08000000 /* transfer */

#define I2C_FUNC_SMBUS_BYTE I2C_FUNC_SMBUS_READ_BYTE | \
                            I2C_FUNC_SMBUS_WRITE_BYTE

#define I2C_FUNC_SMBUS_BYTE_DATA I2C_FUNC_SMBUS_READ_BYTE_DATA | \
                                 I2C_FUNC_SMBUS_WRITE_BYTE_DATA

#define I2C_FUNC_SMBUS_WORD_DATA I2C_FUNC_SMBUS_READ_WORD_DATA | \
                                 I2C_FUNC_SMBUS_WRITE_WORD_DATA

#define I2C_FUNC_SMBUS_BLOCK_DATA I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
                                  I2C_FUNC_SMBUS_WRITE_BLOCK_DATA

#define I2C_FUNC_SMBUS_I2C_BLOCK I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
                                  I2C_FUNC_SMBUS_WRITE_I2C_BLOCK


#define I2C_FUNC_SMBUS_EMUL I2C_FUNC_SMBUS_QUICK | \
                            I2C_FUNC_SMBUS_BYTE | \
                            I2C_FUNC_SMBUS_BYTE_DATA | \
                            I2C_FUNC_SMBUS_WORD_DATA | \
                            I2C_FUNC_SMBUS_PROC_CALL | \
                            I2C_FUNC_SMBUS_WRITE_BLOCK_DATA


/*
 * Data for SMBus Messages
 */

union i2c_smbus_data {
        __u8 byte;
        __u16 word;
        __u8 block[33]; /* block[0] is used for length */
};

/* smbus_access read or write markers */
#define I2C_SMBUS_READ  1
#define I2C_SMBUS_WRITE 0

/* SMBus transaction types (size parameter in the above functions)
   Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */

#define I2C_SMBUS_QUICK             0
#define I2C_SMBUS_BYTE              1
#define I2C_SMBUS_BYTE_DATA         2
#define I2C_SMBUS_WORD_DATA         3
#define I2C_SMBUS_PROC_CALL         4
#define I2C_SMBUS_BLOCK_DATA        5
#define I2C_SMBUS_I2C_BLOCK_DATA    6


/* ----- commands for the ioctl like i2c_command call:
 * note that additional calls are defined in the algorithm and hw
 *      dependent layers - these can be listed here, or see the
 *      corresponding header files.
 */

                                /* -> bit-adapter specific ioctls       */
#define I2C_RETRIES     0x0701  /* number of times a device address      */
                                /* should be polled when not            */
                                /* acknowledging                        */
#define I2C_TIMEOUT     0x0702  /* set timeout - call with int          */


/* this is for i2c-dev.c        */
#define I2C_SLAVE       0x0703  /* Change slave address                 */
                                /* Attn.: Slave address is 7 or 10 bits */
#define I2C_SLAVE_FORCE 0x0706  /* Change slave address                 */
                                /* Attn.: Slave address is 7 or 10 bits */
                                /* This changes the address, even if it */
                                /* is already taken!                    */
#define I2C_TENBIT      0x0704  /* 0 for 7 bit addrs, != 0 for 10 bit   */

#define I2C_FUNCS       0x0705  /* Get the adapter functionality */
#define I2C_RDWR        0x0707  /* Combined R/W transfer (one stop only)*/
#if 0
#define I2C_ACK_TEST    0x0710  /* See if a slave is at a specific address */
#endif

#define I2C_SMBUS       0x0720  /* SMBus-level access */

/* ... algo-bit.c recognizes */
#define I2C_UDELAY      0x0705  /* set delay in microsecs between each  */
                                /* written byte (except address)        */
#define I2C_MDELAY      0x0706  /* millisec delay between written bytes */

/* ----- I2C-DEV: char device interface stuff ------------------------- */

#define I2C_MAJOR       89              /* Device major number          */

#  ifndef NULL
#    define NULL ( (void *) 0 )
#  endif

#  ifndef ENODEV
#    include <asm/errno.h>
#  endif

/* These defines are used for probing i2c client addresses */
/* Default fill of many variables */
#define I2C_CLIENT_DEFAULTS {I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
                          I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
                          I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
                          I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
                          I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
                          I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
                          I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
                          I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
                          I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
                          I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
                          I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
                          I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
                          I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
                          I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
                          I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
                          I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END}


/* This is ugly. We need to evaluate I2C_CLIENT_MAX_OPTS before it is
   stringified */

#define I2C_CLIENT_MODPARM_AUX1(x) "1-" #x "h"
#define I2C_CLIENT_MODPARM_AUX(x) I2C_CLIENT_MODPARM_AUX1(x)
#define I2C_CLIENT_MODPARM I2C_CLIENT_MODPARM_AUX(I2C_CLIENT_MAX_OPTS)

/* I2C_CLIENT_MODULE_PARM creates a module parameter, and puts it in the
   module header */


#define I2C_CLIENT_MODULE_PARM(var,desc) \
  static unsigned short var[I2C_CLIENT_MAX_OPTS] = I2C_CLIENT_DEFAULTS; \
  MODULE_PARM(var,I2C_CLIENT_MODPARM); \
  MODULE_PARM_DESC(var,desc)


/* This is the one you want to use in your own modules */
#define I2C_CLIENT_INSMOD \
  I2C_CLIENT_MODULE_PARM(probe, \
                      "List of adapter,address pairs to scan additionally"); \
  I2C_CLIENT_MODULE_PARM(probe_range, \
                      "List of adapter,start-addr,end-addr triples to scan " \
                      "additionally"); \
  I2C_CLIENT_MODULE_PARM(ignore, \
                      "List of adapter,address pairs not to scan"); \
  I2C_CLIENT_MODULE_PARM(ignore_range, \
                      "List of adapter,start-addr,end-addr triples not to " \
                      "scan"); \
  I2C_CLIENT_MODULE_PARM(force, \
                      "List of adapter,address pairs to boldly assume " \
                      "to be present"); \
  static struct i2c_client_address_data addr_data = \
                                       {normal_i2c, normal_i2c_range, \
                                        probe, probe_range, \
                                        ignore, ignore_range, \
                                        force}


/* Detect whether we are on the isa bus. If this returns true, all i2c
   access will fail! */

#define i2c_is_isa_client(clientptr) \
        ((clientptr)->adapter->algo->id == I2C_ALGO_ISA)

#define i2c_is_isa_adapter(adapptr) \
        ((adapptr)->algo->id == I2C_ALGO_ISA)


#endif /* I2C_H */