Subversion Repositories Kolibri OS

Rev

Rev 1408 | Rev 1631 | Go to most recent revision | Blame | Compare with Previous | Last modification | View Log | Download | RSS feed

  1. /* ------------------------------------------------------------------------- */
  2. /*                                                                           */
  3. /* i2c.h - definitions for the i2c-bus interface                             */
  4. /*                                                                           */
  5. /* ------------------------------------------------------------------------- */
  6. /*   Copyright (C) 1995-2000 Simon G. Vogl
  7.  
  8.     This program is free software; you can redistribute it and/or modify
  9.     it under the terms of the GNU General Public License as published by
  10.     the Free Software Foundation; either version 2 of the License, or
  11.     (at your option) any later version.
  12.  
  13.     This program is distributed in the hope that it will be useful,
  14.     but WITHOUT ANY WARRANTY; without even the implied warranty of
  15.     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16.     GNU General Public License for more details.
  17.  
  18.     You should have received a copy of the GNU General Public License
  19.     along with this program; if not, write to the Free Software
  20.     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.                */
  21. /* ------------------------------------------------------------------------- */
  22.  
  23. /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and
  24.    Frodo Looijaard <frodol@dds.nl> */
  25.  
  26. #ifndef _LINUX_I2C_H
  27. #define _LINUX_I2C_H
  28.  
  29. #include <types.h>
  30. #include <list.h>
  31. #include <linux/module.h>
  32. #include <linux/i2c-id.h>
  33.  
  34.  
  35. #define I2C_NAME_SIZE   20
  36.  
  37. struct i2c_msg;
  38. struct i2c_algorithm;
  39. struct i2c_adapter;
  40. struct i2c_client;
  41. union i2c_smbus_data;
  42.  
  43.  
  44. /* Transfer num messages.
  45.  */
  46. extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
  47.                         int num);
  48.  
  49. /**
  50.  * struct i2c_driver - represent an I2C device driver
  51.  * @class: What kind of i2c device we instantiate (for detect)
  52.  * @attach_adapter: Callback for bus addition (for legacy drivers)
  53.  * @detach_adapter: Callback for bus removal (for legacy drivers)
  54.  * @probe: Callback for device binding
  55.  * @remove: Callback for device unbinding
  56.  * @shutdown: Callback for device shutdown
  57.  * @suspend: Callback for device suspend
  58.  * @resume: Callback for device resume
  59.  * @command: Callback for bus-wide signaling (optional)
  60.  * @driver: Device driver model driver
  61.  * @id_table: List of I2C devices supported by this driver
  62.  * @detect: Callback for device detection
  63.  * @address_list: The I2C addresses to probe (for detect)
  64.  * @clients: List of detected clients we created (for i2c-core use only)
  65.  *
  66.  * The driver.owner field should be set to the module owner of this driver.
  67.  * The driver.name field should be set to the name of this driver.
  68.  *
  69.  * For automatic device detection, both @detect and @address_data must
  70.  * be defined. @class should also be set, otherwise only devices forced
  71.  * with module parameters will be created. The detect function must
  72.  * fill at least the name field of the i2c_board_info structure it is
  73.  * handed upon successful detection, and possibly also the flags field.
  74.  *
  75.  * If @detect is missing, the driver will still work fine for enumerated
  76.  * devices. Detected devices simply won't be supported. This is expected
  77.  * for the many I2C/SMBus devices which can't be detected reliably, and
  78.  * the ones which can always be enumerated in practice.
  79.  *
  80.  * The i2c_client structure which is handed to the @detect callback is
  81.  * not a real i2c_client. It is initialized just enough so that you can
  82.  * call i2c_smbus_read_byte_data and friends on it. Don't do anything
  83.  * else with it. In particular, calling dev_dbg and friends on it is
  84.  * not allowed.
  85.  */
  86. struct i2c_driver {
  87.         unsigned int class;
  88.  
  89.         /* Notifies the driver that a new bus has appeared or is about to be
  90.          * removed. You should avoid using this if you can, it will probably
  91.          * be removed in a near future.
  92.          */
  93.         int (*attach_adapter)(struct i2c_adapter *);
  94.         int (*detach_adapter)(struct i2c_adapter *);
  95.  
  96.         /* Standard driver model interfaces */
  97.         int (*probe)(struct i2c_client *, const struct i2c_device_id *);
  98.         int (*remove)(struct i2c_client *);
  99.  
  100.         /* driver model interfaces that don't relate to enumeration  */
  101.         void (*shutdown)(struct i2c_client *);
  102. //      int (*suspend)(struct i2c_client *, pm_message_t mesg);
  103.         int (*resume)(struct i2c_client *);
  104.  
  105.         /* Alert callback, for example for the SMBus alert protocol.
  106.          * The format and meaning of the data value depends on the protocol.
  107.          * For the SMBus alert protocol, there is a single bit of data passed
  108.          * as the alert response's low bit ("event flag").
  109.          */
  110.         void (*alert)(struct i2c_client *, unsigned int data);
  111.  
  112.         /* a ioctl like command that can be used to perform specific functions
  113.          * with the device.
  114.          */
  115.         int (*command)(struct i2c_client *client, unsigned int cmd, void *arg);
  116.  
  117. //      struct device_driver driver;
  118.         const struct i2c_device_id *id_table;
  119.  
  120.         /* Device detection callback for automatic device creation */
  121. //      int (*detect)(struct i2c_client *, struct i2c_board_info *);
  122.         const unsigned short *address_list;
  123.         struct list_head clients;
  124. };
  125. #define to_i2c_driver(d) container_of(d, struct i2c_driver, driver)
  126.  
  127. /**
  128.  * struct i2c_client - represent an I2C slave device
  129.  * @flags: I2C_CLIENT_TEN indicates the device uses a ten bit chip address;
  130.  *      I2C_CLIENT_PEC indicates it uses SMBus Packet Error Checking
  131.  * @addr: Address used on the I2C bus connected to the parent adapter.
  132.  * @name: Indicates the type of the device, usually a chip name that's
  133.  *      generic enough to hide second-sourcing and compatible revisions.
  134.  * @adapter: manages the bus segment hosting this I2C device
  135.  * @driver: device's driver, hence pointer to access routines
  136.  * @dev: Driver model device node for the slave.
  137.  * @irq: indicates the IRQ generated by this device (if any)
  138.  * @detected: member of an i2c_driver.clients list or i2c-core's
  139.  *      userspace_devices list
  140.  *
  141.  * An i2c_client identifies a single device (i.e. chip) connected to an
  142.  * i2c bus. The behaviour exposed to Linux is defined by the driver
  143.  * managing the device.
  144.  */
  145. struct i2c_client {
  146.         unsigned short flags;           /* div., see below              */
  147.         unsigned short addr;            /* chip address - NOTE: 7bit    */
  148.                                         /* addresses are stored in the  */
  149.                                         /* _LOWER_ 7 bits               */
  150.         char name[I2C_NAME_SIZE];
  151.         struct i2c_adapter *adapter;    /* the adapter we sit on        */
  152.     struct i2c_driver *driver;      /* and our access routines      */
  153. //        struct device dev;              /* the device structure         */
  154.     int irq;                        /* irq issued by device (or -1) */
  155.         struct list_head detected;
  156. };
  157. #define to_i2c_client(d) container_of(d, struct i2c_client, dev)
  158.  
  159. extern struct i2c_client *i2c_verify_client(struct device *dev);
  160.  
  161. /*
  162.  * The following structs are for those who like to implement new bus drivers:
  163.  * i2c_algorithm is the interface to a class of hardware solutions which can
  164.  * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584
  165.  * to name two of the most common.
  166.  */
  167. struct i2c_algorithm {
  168.         /* If an adapter algorithm can't do I2C-level access, set master_xfer
  169.            to NULL. If an adapter algorithm can do SMBus access, set
  170.            smbus_xfer. If set to NULL, the SMBus protocol is simulated
  171.            using common I2C messages */
  172.         /* master_xfer should return the number of messages successfully
  173.            processed, or a negative value on error */
  174.         int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs,
  175.                            int num);
  176.         int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr,
  177.                            unsigned short flags, char read_write,
  178.                            u8 command, int size, union i2c_smbus_data *data);
  179.  
  180.         /* To determine what the adapter supports */
  181.         u32 (*functionality) (struct i2c_adapter *);
  182. };
  183.  
  184. /*
  185.  * i2c_adapter is the structure used to identify a physical i2c bus along
  186.  * with the access algorithms necessary to access it.
  187.  */
  188. struct i2c_adapter {
  189.         unsigned int id;
  190.         unsigned int class;               /* classes to allow probing for */
  191.         const struct i2c_algorithm *algo; /* the algorithm to access the bus */
  192.         void *algo_data;
  193.  
  194.         /* data fields that are valid for all devices   */
  195. //      struct rt_mutex bus_lock;
  196.  
  197.         int timeout;                    /* in jiffies */
  198.     int retries;
  199.     struct device dev;      /* the adapter device */
  200.  
  201.     int nr;
  202.     char name[48];
  203. };
  204. #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
  205.  
  206. static inline void *i2c_get_adapdata(const struct i2c_adapter *dev)
  207. {
  208.         return dev_get_drvdata(&dev->dev);
  209. }
  210.  
  211. static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data)
  212. {
  213.         dev_set_drvdata(&dev->dev, data);
  214. }
  215.  
  216. /*flags for the client struct: */
  217. #define I2C_CLIENT_PEC  0x04            /* Use Packet Error Checking */
  218. #define I2C_CLIENT_TEN  0x10            /* we have a ten bit chip address */
  219.                                         /* Must equal I2C_M_TEN below */
  220. #define I2C_CLIENT_WAKE 0x80            /* for board_info; true iff can wake */
  221.  
  222. /* i2c adapter classes (bitmask) */
  223. #define I2C_CLASS_HWMON         (1<<0)  /* lm_sensors, ... */
  224. #define I2C_CLASS_TV_ANALOG     (1<<1)  /* bttv + friends */
  225. #define I2C_CLASS_TV_DIGITAL    (1<<2)  /* dvb cards */
  226. #define I2C_CLASS_DDC           (1<<3)  /* DDC bus on graphics adapters */
  227. #define I2C_CLASS_SPD           (1<<7)  /* SPD EEPROMs and similar */
  228.  
  229. /* Internal numbers to terminate lists */
  230. #define I2C_CLIENT_END          0xfffeU
  231.  
  232. /* The numbers to use to set I2C bus address */
  233. #define ANY_I2C_BUS             0xffff
  234.  
  235. /* Construct an I2C_CLIENT_END-terminated array of i2c addresses */
  236. #define I2C_ADDRS(addr, addrs...) \
  237.         ((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END })
  238.  
  239.  
  240. /**
  241.  * struct i2c_msg - an I2C transaction segment beginning with START
  242.  * @addr: Slave address, either seven or ten bits.  When this is a ten
  243.  *      bit address, I2C_M_TEN must be set in @flags and the adapter
  244.  *      must support I2C_FUNC_10BIT_ADDR.
  245.  * @flags: I2C_M_RD is handled by all adapters.  No other flags may be
  246.  *      provided unless the adapter exported the relevant I2C_FUNC_*
  247.  *      flags through i2c_check_functionality().
  248.  * @len: Number of data bytes in @buf being read from or written to the
  249.  *      I2C slave address.  For read transactions where I2C_M_RECV_LEN
  250.  *      is set, the caller guarantees that this buffer can hold up to
  251.  *      32 bytes in addition to the initial length byte sent by the
  252.  *      slave (plus, if used, the SMBus PEC); and this value will be
  253.  *      incremented by the number of block data bytes received.
  254.  * @buf: The buffer into which data is read, or from which it's written.
  255.  *
  256.  * An i2c_msg is the low level representation of one segment of an I2C
  257.  * transaction.  It is visible to drivers in the @i2c_transfer() procedure,
  258.  * to userspace from i2c-dev, and to I2C adapter drivers through the
  259.  * @i2c_adapter.@master_xfer() method.
  260.  *
  261.  * Except when I2C "protocol mangling" is used, all I2C adapters implement
  262.  * the standard rules for I2C transactions.  Each transaction begins with a
  263.  * START.  That is followed by the slave address, and a bit encoding read
  264.  * versus write.  Then follow all the data bytes, possibly including a byte
  265.  * with SMBus PEC.  The transfer terminates with a NAK, or when all those
  266.  * bytes have been transferred and ACKed.  If this is the last message in a
  267.  * group, it is followed by a STOP.  Otherwise it is followed by the next
  268.  * @i2c_msg transaction segment, beginning with a (repeated) START.
  269.  *
  270.  * Alternatively, when the adapter supports I2C_FUNC_PROTOCOL_MANGLING then
  271.  * passing certain @flags may have changed those standard protocol behaviors.
  272.  * Those flags are only for use with broken/nonconforming slaves, and with
  273.  * adapters which are known to support the specific mangling options they
  274.  * need (one or more of IGNORE_NAK, NO_RD_ACK, NOSTART, and REV_DIR_ADDR).
  275.  */
  276. struct i2c_msg {
  277.         u16 addr;     /* slave address                        */
  278.         u16 flags;
  279. #define I2C_M_TEN               0x0010  /* this is a ten bit chip address */
  280. #define I2C_M_RD                0x0001  /* read data, from slave to master */
  281. #define I2C_M_NOSTART           0x4000  /* if I2C_FUNC_PROTOCOL_MANGLING */
  282. #define I2C_M_REV_DIR_ADDR      0x2000  /* if I2C_FUNC_PROTOCOL_MANGLING */
  283. #define I2C_M_IGNORE_NAK        0x1000  /* if I2C_FUNC_PROTOCOL_MANGLING */
  284. #define I2C_M_NO_RD_ACK         0x0800  /* if I2C_FUNC_PROTOCOL_MANGLING */
  285. #define I2C_M_RECV_LEN          0x0400  /* length will be first received byte */
  286.         u16 len;              /* msg length                           */
  287.         u8 *buf;              /* pointer to msg data                  */
  288. };
  289.  
  290. /* To determine what functionality is present */
  291.  
  292. #define I2C_FUNC_I2C                    0x00000001
  293. #define I2C_FUNC_10BIT_ADDR             0x00000002
  294. #define I2C_FUNC_PROTOCOL_MANGLING      0x00000004 /* I2C_M_NOSTART etc. */
  295. #define I2C_FUNC_SMBUS_PEC              0x00000008
  296. #define I2C_FUNC_SMBUS_BLOCK_PROC_CALL  0x00008000 /* SMBus 2.0 */
  297. #define I2C_FUNC_SMBUS_QUICK            0x00010000
  298. #define I2C_FUNC_SMBUS_READ_BYTE        0x00020000
  299. #define I2C_FUNC_SMBUS_WRITE_BYTE       0x00040000
  300. #define I2C_FUNC_SMBUS_READ_BYTE_DATA   0x00080000
  301. #define I2C_FUNC_SMBUS_WRITE_BYTE_DATA  0x00100000
  302. #define I2C_FUNC_SMBUS_READ_WORD_DATA   0x00200000
  303. #define I2C_FUNC_SMBUS_WRITE_WORD_DATA  0x00400000
  304. #define I2C_FUNC_SMBUS_PROC_CALL        0x00800000
  305. #define I2C_FUNC_SMBUS_READ_BLOCK_DATA  0x01000000
  306. #define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
  307. #define I2C_FUNC_SMBUS_READ_I2C_BLOCK   0x04000000 /* I2C-like block xfer  */
  308. #define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK  0x08000000 /* w/ 1-byte reg. addr. */
  309.  
  310. #define I2C_FUNC_SMBUS_BYTE             (I2C_FUNC_SMBUS_READ_BYTE | \
  311.                                          I2C_FUNC_SMBUS_WRITE_BYTE)
  312. #define I2C_FUNC_SMBUS_BYTE_DATA        (I2C_FUNC_SMBUS_READ_BYTE_DATA | \
  313.                                          I2C_FUNC_SMBUS_WRITE_BYTE_DATA)
  314. #define I2C_FUNC_SMBUS_WORD_DATA        (I2C_FUNC_SMBUS_READ_WORD_DATA | \
  315.                                          I2C_FUNC_SMBUS_WRITE_WORD_DATA)
  316. #define I2C_FUNC_SMBUS_BLOCK_DATA       (I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
  317.                                          I2C_FUNC_SMBUS_WRITE_BLOCK_DATA)
  318. #define I2C_FUNC_SMBUS_I2C_BLOCK        (I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
  319.                                          I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)
  320.  
  321. #define I2C_FUNC_SMBUS_EMUL             (I2C_FUNC_SMBUS_QUICK | \
  322.                                          I2C_FUNC_SMBUS_BYTE | \
  323.                                          I2C_FUNC_SMBUS_BYTE_DATA | \
  324.                                          I2C_FUNC_SMBUS_WORD_DATA | \
  325.                                          I2C_FUNC_SMBUS_PROC_CALL | \
  326.                                          I2C_FUNC_SMBUS_WRITE_BLOCK_DATA | \
  327.                                          I2C_FUNC_SMBUS_I2C_BLOCK | \
  328.                                          I2C_FUNC_SMBUS_PEC)
  329.  
  330. /*
  331.  * Data for SMBus Messages
  332.  */
  333. #define I2C_SMBUS_BLOCK_MAX     32      /* As specified in SMBus standard */
  334. union i2c_smbus_data {
  335.         __u8 byte;
  336.         __u16 word;
  337.         __u8 block[I2C_SMBUS_BLOCK_MAX + 2]; /* block[0] is used for length */
  338.                                /* and one more for user-space compatibility */
  339. };
  340.  
  341. /* i2c_smbus_xfer read or write markers */
  342. #define I2C_SMBUS_READ  1
  343. #define I2C_SMBUS_WRITE 0
  344.  
  345. /* SMBus transaction types (size parameter in the above functions)
  346.    Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
  347. #define I2C_SMBUS_QUICK             0
  348. #define I2C_SMBUS_BYTE              1
  349. #define I2C_SMBUS_BYTE_DATA         2
  350. #define I2C_SMBUS_WORD_DATA         3
  351. #define I2C_SMBUS_PROC_CALL         4
  352. #define I2C_SMBUS_BLOCK_DATA        5
  353. #define I2C_SMBUS_I2C_BLOCK_BROKEN  6
  354. #define I2C_SMBUS_BLOCK_PROC_CALL   7           /* SMBus 2.0 */
  355. #define I2C_SMBUS_I2C_BLOCK_DATA    8
  356.  
  357. #endif /* _LINUX_I2C_H */
  358.