WSL2-Linux-Kernel/include/linux/i2c.h

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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> */
#ifndef _LINUX_I2C_H
#define _LINUX_I2C_H
#include <linux/types.h>
#ifdef __KERNEL__
#include <linux/module.h>
#include <linux/i2c-id.h>
#include <linux/mod_devicetable.h>
#include <linux/device.h> /* for struct device */
#include <linux/sched.h> /* for completion */
#include <linux/mutex.h>
extern struct bus_type i2c_bus_type;
/* --- General options ------------------------------------------------ */
struct i2c_msg;
struct i2c_algorithm;
struct i2c_adapter;
struct i2c_client;
struct i2c_driver;
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 *msgs, int num);
/* 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);
/* 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,
const u8 *values);
/* Returns the number of read bytes */
extern s32 i2c_smbus_read_i2c_block_data(struct i2c_client * client,
u8 command, u8 *values);
extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client * client,
u8 command, u8 length,
const 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.
*
* The driver.owner field should be set to the module owner of this driver.
* The driver.name field should be set to the name of this driver.
*/
struct i2c_driver {
int id;
unsigned int class;
/* 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. (LEGACY I2C DRIVERS ONLY)
*/
int (*attach_adapter)(struct i2c_adapter *);
int (*detach_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. (LEGACY I2C DRIVERS ONLY)
*/
int (*detach_client)(struct i2c_client *);
/* Standard driver model interfaces, for "new style" i2c drivers.
* With the driver model, device enumeration is NEVER done by drivers;
* it's done by infrastructure. (NEW STYLE DRIVERS ONLY)
*/
int (*probe)(struct i2c_client *);
int (*remove)(struct i2c_client *);
/* driver model interfaces that don't relate to enumeration */
void (*shutdown)(struct i2c_client *);
int (*suspend)(struct i2c_client *, pm_message_t mesg);
int (*resume)(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);
struct device_driver driver;
struct list_head list;
};
#define to_i2c_driver(d) container_of(d, struct i2c_driver, driver)
#define I2C_NAME_SIZE 20
/**
* struct i2c_client - represent an I2C slave device
* @addr: Address used on the I2C bus connected to the parent adapter.
* @name: Indicates the type of the device, usually a chip name that's
* generic enough to hide second-sourcing and compatible revisions.
* @dev: Driver model device node for the slave.
* @driver_name: Identifies new-style driver used with this device; also
* used as the module name for hotplug/coldplug modprobe support.
*
* An i2c_client identifies a single device (i.e. chip) connected to an
* i2c bus. The behaviour is defined by the routines of the driver.
*/
struct i2c_client {
unsigned short flags; /* div., see below */
unsigned short addr; /* chip address - NOTE: 7bit */
/* addresses are stored in the */
/* _LOWER_ 7 bits */
char name[I2C_NAME_SIZE];
struct i2c_adapter *adapter; /* the adapter we sit on */
struct i2c_driver *driver; /* and our access routines */
int usage_count; /* How many accesses currently */
/* to the client */
struct device dev; /* the device structure */
i2c: Add i2c_board_info and i2c_new_device() This provides partial support for new-style I2C driver binding. It builds on "struct i2c_board_info" declarations that identify I2C devices on a given board. This is needed on systems with I2C devices that can't be fully probed and/or autoconfigured, such as many embedded Linux configurations where the way a given I2C device is wired may affect how it must be used. There are two models for declaring such devices: * LATE -- using a public function i2c_new_device(). This lets modules declare I2C devices found *AFTER* a given I2C adapter becomes available. For example, a PCI card could create adapters giving access to utility chips on that card, and this would be used to associate those chips with those adapters. * EARLY -- from arch_initcall() level code, using a non-exported function i2c_register_board_info(). This copies the declarations *BEFORE* such an i2c_adapter becomes available, arranging that i2c_new_device() will be called later when i2c-core registers the relevant i2c_adapter. For example, arch/.../.../board-*.c files would declare the I2C devices along with their platform data, and I2C devices would behave much like PNPACPI devices. (That is, both enumerate from board-specific tables.) To match the exported i2c_new_device(), the previously-private function i2c_unregister_device() is now exported. Pending later patches using these new APIs, this is effectively a NOP. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-05-02 01:26:31 +04:00
int irq; /* irq issued by device (or -1) */
char driver_name[KOBJ_NAME_LEN];
struct list_head list;
struct completion released;
};
#define to_i2c_client(d) container_of(d, struct i2c_client, dev)
static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj)
{
return to_i2c_client(container_of(kobj, struct device, kobj));
}
static inline void *i2c_get_clientdata (struct i2c_client *dev)
{
return dev_get_drvdata (&dev->dev);
}
static inline void i2c_set_clientdata (struct i2c_client *dev, void *data)
{
dev_set_drvdata (&dev->dev, data);
}
i2c: Add i2c_board_info and i2c_new_device() This provides partial support for new-style I2C driver binding. It builds on "struct i2c_board_info" declarations that identify I2C devices on a given board. This is needed on systems with I2C devices that can't be fully probed and/or autoconfigured, such as many embedded Linux configurations where the way a given I2C device is wired may affect how it must be used. There are two models for declaring such devices: * LATE -- using a public function i2c_new_device(). This lets modules declare I2C devices found *AFTER* a given I2C adapter becomes available. For example, a PCI card could create adapters giving access to utility chips on that card, and this would be used to associate those chips with those adapters. * EARLY -- from arch_initcall() level code, using a non-exported function i2c_register_board_info(). This copies the declarations *BEFORE* such an i2c_adapter becomes available, arranging that i2c_new_device() will be called later when i2c-core registers the relevant i2c_adapter. For example, arch/.../.../board-*.c files would declare the I2C devices along with their platform data, and I2C devices would behave much like PNPACPI devices. (That is, both enumerate from board-specific tables.) To match the exported i2c_new_device(), the previously-private function i2c_unregister_device() is now exported. Pending later patches using these new APIs, this is effectively a NOP. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-05-02 01:26:31 +04:00
/**
* struct i2c_board_info - template for device creation
* @driver_name: identifies the driver to be bound to the device
* @type: optional chip type information, to initialize i2c_client.name
* @flags: to initialize i2c_client.flags
* @addr: stored in i2c_client.addr
* @platform_data: stored in i2c_client.dev.platform_data
* @irq: stored in i2c_client.irq
* I2C doesn't actually support hardware probing, although controllers and
* devices may be able to use I2C_SMBUS_QUICK to tell whether or not there's
* a device at a given address. Drivers commonly need more information than
* that, such as chip type, configuration, associated IRQ, and so on.
*
* i2c_board_info is used to build tables of information listing I2C devices
* that are present. This information is used to grow the driver model tree
* for "new style" I2C drivers. For mainboards this is done statically using
* i2c_register_board_info(), where @bus_num represents an adapter that isn't
* yet available. For add-on boards, i2c_new_device() does this dynamically
* with the adapter already known.
*/
struct i2c_board_info {
char driver_name[KOBJ_NAME_LEN];
char type[I2C_NAME_SIZE];
unsigned short flags;
unsigned short addr;
void *platform_data;
int irq;
};
/**
* I2C_BOARD_INFO - macro used to list an i2c device and its driver
* @driver: identifies the driver to use with the device
* @dev_addr: the device's address on the bus.
*
* This macro initializes essential fields of a struct i2c_board_info,
* declaring what has been provided on a particular board. Optional
* fields (such as the chip type, its associated irq, or device-specific
* platform_data) are provided using conventional syntax.
*/
#define I2C_BOARD_INFO(driver,dev_addr) \
.driver_name = (driver), .addr = (dev_addr)
/* Add-on boards should register/unregister their devices; e.g. a board
* with integrated I2C, a config eeprom, sensors, and a codec that's
* used in conjunction with the primary hardware.
*/
extern struct i2c_client *
i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info);
/* If you don't know the exact address of an I2C device, use this variant
* instead, which can probe for device presence in a list of possible
* addresses.
*/
extern struct i2c_client *
i2c_new_probed_device(struct i2c_adapter *adap,
struct i2c_board_info *info,
unsigned short const *addr_list);
i2c: Add i2c_board_info and i2c_new_device() This provides partial support for new-style I2C driver binding. It builds on "struct i2c_board_info" declarations that identify I2C devices on a given board. This is needed on systems with I2C devices that can't be fully probed and/or autoconfigured, such as many embedded Linux configurations where the way a given I2C device is wired may affect how it must be used. There are two models for declaring such devices: * LATE -- using a public function i2c_new_device(). This lets modules declare I2C devices found *AFTER* a given I2C adapter becomes available. For example, a PCI card could create adapters giving access to utility chips on that card, and this would be used to associate those chips with those adapters. * EARLY -- from arch_initcall() level code, using a non-exported function i2c_register_board_info(). This copies the declarations *BEFORE* such an i2c_adapter becomes available, arranging that i2c_new_device() will be called later when i2c-core registers the relevant i2c_adapter. For example, arch/.../.../board-*.c files would declare the I2C devices along with their platform data, and I2C devices would behave much like PNPACPI devices. (That is, both enumerate from board-specific tables.) To match the exported i2c_new_device(), the previously-private function i2c_unregister_device() is now exported. Pending later patches using these new APIs, this is effectively a NOP. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-05-02 01:26:31 +04:00
extern void i2c_unregister_device(struct i2c_client *);
/* Mainboard arch_initcall() code should register all its I2C devices.
* This is done at arch_initcall time, before declaring any i2c adapters.
* Modules for add-on boards must use other calls.
*/
extern int
i2c_register_board_info(int busnum, struct i2c_board_info const *info, unsigned n);
/*
* 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 {
/* If an adapter algorithm can't do 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 */
/* master_xfer should return the number of messages successfully
processed, or a negative value on error */
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);
/* --- 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 {
struct module *owner;
unsigned int id;
unsigned int class;
const struct i2c_algorithm *algo; /* the algorithm to access the bus */
void *algo_data;
/* --- administration stuff. */
int (*client_register)(struct i2c_client *);
int (*client_unregister)(struct i2c_client *);
/* data fields that are valid for all devices */
u8 level; /* nesting level for lockdep */
struct mutex bus_lock;
struct mutex clist_lock;
int timeout;
int retries;
struct device dev; /* the adapter device */
int nr;
struct list_head clients;
struct list_head list;
char name[48];
struct completion dev_released;
};
#define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
static inline void *i2c_get_adapdata (struct i2c_adapter *dev)
{
return dev_get_drvdata (&dev->dev);
}
static inline void i2c_set_adapdata (struct i2c_adapter *dev, void *data)
{
dev_set_drvdata (&dev->dev, data);
}
/*flags for the client struct: */
#define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */
#define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */
/* Must equal I2C_M_TEN below */
/* i2c adapter classes (bitmask) */
#define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */
#define I2C_CLASS_TV_ANALOG (1<<1) /* bttv + friends */
#define I2C_CLASS_TV_DIGITAL (1<<2) /* dvb cards */
#define I2C_CLASS_DDC (1<<3) /* i2c-matroxfb ? */
#define I2C_CLASS_CAM_ANALOG (1<<4) /* camera with analog CCD */
#define I2C_CLASS_CAM_DIGITAL (1<<5) /* most webcams */
#define I2C_CLASS_SOUND (1<<6) /* sound devices */
#define I2C_CLASS_ALL (UINT_MAX) /* all of the above */
/* 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 *probe;
unsigned short *ignore;
unsigned short **forces;
};
/* Internal numbers to terminate lists */
#define I2C_CLIENT_END 0xfffeU
/* The numbers to use to set I2C bus address */
#define ANY_I2C_BUS 0xffff
#define ANY_I2C_ISA_BUS 9191
/* ----- 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_numbered_adapter(struct i2c_adapter *);
extern int i2c_register_driver(struct module *, struct i2c_driver *);
extern void i2c_del_driver(struct i2c_driver *);
static inline int i2c_add_driver(struct i2c_driver *driver)
{
return i2c_register_driver(THIS_MODULE, driver);
}
extern int i2c_attach_client(struct i2c_client *);
extern int i2c_detach_client(struct i2c_client *);
/* Should be used to make sure that client-struct is valid and that it
is okay to access the i2c-client.
returns -ENODEV if client has gone in the meantime */
extern int i2c_use_client(struct i2c_client *);
extern int i2c_release_client(struct i2c_client *);
/* call the i2c_client->command() of all attached clients with
* the given arguments */
extern void i2c_clients_command(struct i2c_adapter *adap,
unsigned int cmd, void *arg);
/* 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);
*/
extern int i2c_probe(struct i2c_adapter *adapter,
struct i2c_client_address_data *address_data,
int (*found_proc) (struct i2c_adapter *, int, int));
/* An ioctl like call to set div. parameters of the adapter.
*/
extern int i2c_control(struct i2c_client *,unsigned int, unsigned long);
extern struct i2c_adapter* i2c_get_adapter(int id);
extern void i2c_put_adapter(struct i2c_adapter *adap);
/* Return the functionality mask */
static inline u32 i2c_get_functionality(struct i2c_adapter *adap)
{
return adap->algo->functionality(adap);
}
/* Return 1 if adapter supports everything we need, 0 if not. */
static inline int i2c_check_functionality(struct i2c_adapter *adap, u32 func)
{
return (func & i2c_get_functionality(adap)) == func;
}
/* Return id number for a specific adapter */
static inline int i2c_adapter_id(struct i2c_adapter *adap)
{
return adap->nr;
}
#endif /* __KERNEL__ */
/*
* I2C Message - used for pure i2c transaction, also from /dev interface
*/
struct i2c_msg {
__u16 addr; /* slave address */
__u16 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
#define I2C_M_IGNORE_NAK 0x1000
#define I2C_M_NO_RD_ACK 0x0800
#define I2C_M_RECV_LEN 0x0400 /* length will be first received byte */
__u16 len; /* msg length */
__u8 *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_HWPEC_CALC 0x00000008 /* SMBus 2.0 */
#define I2C_FUNC_SMBUS_BLOCK_PROC_CALL 0x00008000 /* SMBus 2.0 */
#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 /* I2C-like block xfer */
#define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* w/ 1-byte reg. addr. */
#define I2C_FUNC_SMBUS_READ_I2C_BLOCK_2 0x10000000 /* I2C-like block xfer */
#define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK_2 0x20000000 /* w/ 2-byte reg. addr. */
#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_I2C_BLOCK_2 (I2C_FUNC_SMBUS_READ_I2C_BLOCK_2 | \
I2C_FUNC_SMBUS_WRITE_I2C_BLOCK_2)
#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 | \
I2C_FUNC_SMBUS_I2C_BLOCK)
/*
* Data for SMBus Messages
*/
#define I2C_SMBUS_BLOCK_MAX 32 /* As specified in SMBus standard */
union i2c_smbus_data {
__u8 byte;
__u16 word;
__u8 block[I2C_SMBUS_BLOCK_MAX + 2]; /* block[0] is used for length */
[PATCH] i2c: SMBus PEC support rewrite, 2 of 3 This is my rewrite of the SMBus PEC support. The original implementation was known to have bugs (credits go to Hideki Iwamoto for reporting many of them recently), and was incomplete due to a conceptual limitation. The rewrite affects only software PEC. Hardware PEC needs very little code and is mostly untouched. Technically, both implementations differ in that the original one was emulating PEC in software by modifying the contents of an i2c_smbus_data union (changing the transaction to a different type), while the new one works one level lower, on i2c_msg structures (working on message contents). Due to the definition of the i2c_smbus_data union, not all SMBus transactions could be handled (at least not without changing the definition of this union, which would break user-space compatibility), and those which could had to be implemented individually. At the opposite, adding PEC to an i2c_msg structure can be done on any SMBus transaction with common code. Advantages of the new implementation: * It's about twice as small (from ~136 lines before to ~70 now, only counting i2c-core, including blank and comment lines). The memory used by i2c-core is down by ~640 bytes (~3.5%). * Easier to validate, less tricky code. The code being common to all transactions by design, the risk that a bug can stay uncovered is lower. * All SMBus transactions have PEC support in I2C emulation mode (providing the non-PEC transaction is also implemented). Transactions which have no emulation code right now will get PEC support for free when they finally get implemented. * Allows for code simplifications in header files and bus drivers (patch follows). Drawbacks (I guess there had to be at least one): * PEC emulation for non-PEC capable non-I2C SMBus masters was dropped. It was based on SMBus tricks and doesn't quite fit in the new design. I don't think it's really a problem, as the benefit was certainly not worth the additional complexity, but it's only fair that I at least mention it. Lastly, let's note that the new implementation does slightly affect compatibility (both in kernel and user-space), but doesn't actually break it. Some defines will be dropped, but the code can always be changed in a way that will work with both the old and the new implementations. It shouldn't be a problem as there doesn't seem to be many users of SMBus PEC to date anyway. Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-10-26 23:28:55 +04:00
/* and one more for user-space compatibility */
};
/* 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
#define I2C_SMBUS_BLOCK_PROC_CALL 7 /* SMBus 2.0 */
/* ----- 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)*/
#define I2C_PEC 0x0708 /* != 0 for SMBus PEC */
#define I2C_SMBUS 0x0720 /* SMBus-level access */
/* ----- I2C-DEV: char device interface stuff ------------------------- */
#ifdef __KERNEL__
#define I2C_MAJOR 89 /* Device major number */
/* These defines are used for probing i2c client addresses */
/* The length of the option lists */
#define I2C_CLIENT_MAX_OPTS 48
/* 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}
/* 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; \
static unsigned int var##_num; \
module_param_array(var, short, &var##_num, 0); \
MODULE_PARM_DESC(var,desc)
#define I2C_CLIENT_MODULE_PARM_FORCE(name) \
I2C_CLIENT_MODULE_PARM(force_##name, \
"List of adapter,address pairs which are " \
"unquestionably assumed to contain a `" \
# name "' chip")
#define I2C_CLIENT_INSMOD_COMMON \
I2C_CLIENT_MODULE_PARM(probe, "List of adapter,address pairs to scan " \
"additionally"); \
I2C_CLIENT_MODULE_PARM(ignore, "List of adapter,address pairs not to " \
"scan"); \
static struct i2c_client_address_data addr_data = { \
.normal_i2c = normal_i2c, \
.probe = probe, \
.ignore = ignore, \
.forces = forces, \
}
/* These are the ones you want to use in your own drivers. Pick the one
which matches the number of devices the driver differenciates between. */
#define I2C_CLIENT_INSMOD \
I2C_CLIENT_MODULE_PARM(force, \
"List of adapter,address pairs to boldly assume " \
"to be present"); \
static unsigned short *forces[] = { \
force, \
NULL \
}; \
I2C_CLIENT_INSMOD_COMMON
#define I2C_CLIENT_INSMOD_1(chip1) \
enum chips { any_chip, chip1 }; \
I2C_CLIENT_MODULE_PARM(force, "List of adapter,address pairs to " \
"boldly assume to be present"); \
I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
static unsigned short *forces[] = { force, force_##chip1, NULL }; \
I2C_CLIENT_INSMOD_COMMON
#define I2C_CLIENT_INSMOD_2(chip1, chip2) \
enum chips { any_chip, chip1, chip2 }; \
I2C_CLIENT_MODULE_PARM(force, "List of adapter,address pairs to " \
"boldly assume to be present"); \
I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
static unsigned short *forces[] = { force, force_##chip1, \
force_##chip2, NULL }; \
I2C_CLIENT_INSMOD_COMMON
#define I2C_CLIENT_INSMOD_3(chip1, chip2, chip3) \
enum chips { any_chip, chip1, chip2, chip3 }; \
I2C_CLIENT_MODULE_PARM(force, "List of adapter,address pairs to " \
"boldly assume to be present"); \
I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
static unsigned short *forces[] = { force, force_##chip1, \
force_##chip2, force_##chip3, \
NULL }; \
I2C_CLIENT_INSMOD_COMMON
#define I2C_CLIENT_INSMOD_4(chip1, chip2, chip3, chip4) \
enum chips { any_chip, chip1, chip2, chip3, chip4 }; \
I2C_CLIENT_MODULE_PARM(force, "List of adapter,address pairs to " \
"boldly assume to be present"); \
I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
I2C_CLIENT_MODULE_PARM_FORCE(chip4); \
static unsigned short *forces[] = { force, force_##chip1, \
force_##chip2, force_##chip3, \
force_##chip4, NULL}; \
I2C_CLIENT_INSMOD_COMMON
#define I2C_CLIENT_INSMOD_5(chip1, chip2, chip3, chip4, chip5) \
enum chips { any_chip, chip1, chip2, chip3, chip4, chip5 }; \
I2C_CLIENT_MODULE_PARM(force, "List of adapter,address pairs to " \
"boldly assume to be present"); \
I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
I2C_CLIENT_MODULE_PARM_FORCE(chip4); \
I2C_CLIENT_MODULE_PARM_FORCE(chip5); \
static unsigned short *forces[] = { force, force_##chip1, \
force_##chip2, force_##chip3, \
force_##chip4, force_##chip5, \
NULL }; \
I2C_CLIENT_INSMOD_COMMON
#define I2C_CLIENT_INSMOD_6(chip1, chip2, chip3, chip4, chip5, chip6) \
enum chips { any_chip, chip1, chip2, chip3, chip4, chip5, chip6 }; \
I2C_CLIENT_MODULE_PARM(force, "List of adapter,address pairs to " \
"boldly assume to be present"); \
I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
I2C_CLIENT_MODULE_PARM_FORCE(chip4); \
I2C_CLIENT_MODULE_PARM_FORCE(chip5); \
I2C_CLIENT_MODULE_PARM_FORCE(chip6); \
static unsigned short *forces[] = { force, force_##chip1, \
force_##chip2, force_##chip3, \
force_##chip4, force_##chip5, \
force_##chip6, NULL }; \
I2C_CLIENT_INSMOD_COMMON
#define I2C_CLIENT_INSMOD_7(chip1, chip2, chip3, chip4, chip5, chip6, chip7) \
enum chips { any_chip, chip1, chip2, chip3, chip4, chip5, chip6, \
chip7 }; \
I2C_CLIENT_MODULE_PARM(force, "List of adapter,address pairs to " \
"boldly assume to be present"); \
I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
I2C_CLIENT_MODULE_PARM_FORCE(chip4); \
I2C_CLIENT_MODULE_PARM_FORCE(chip5); \
I2C_CLIENT_MODULE_PARM_FORCE(chip6); \
I2C_CLIENT_MODULE_PARM_FORCE(chip7); \
static unsigned short *forces[] = { force, force_##chip1, \
force_##chip2, force_##chip3, \
force_##chip4, force_##chip5, \
force_##chip6, force_##chip7, \
NULL }; \
I2C_CLIENT_INSMOD_COMMON
#define I2C_CLIENT_INSMOD_8(chip1, chip2, chip3, chip4, chip5, chip6, chip7, chip8) \
enum chips { any_chip, chip1, chip2, chip3, chip4, chip5, chip6, \
chip7, chip8 }; \
I2C_CLIENT_MODULE_PARM(force, "List of adapter,address pairs to " \
"boldly assume to be present"); \
I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
I2C_CLIENT_MODULE_PARM_FORCE(chip4); \
I2C_CLIENT_MODULE_PARM_FORCE(chip5); \
I2C_CLIENT_MODULE_PARM_FORCE(chip6); \
I2C_CLIENT_MODULE_PARM_FORCE(chip7); \
I2C_CLIENT_MODULE_PARM_FORCE(chip8); \
static unsigned short *forces[] = { force, force_##chip1, \
force_##chip2, force_##chip3, \
force_##chip4, force_##chip5, \
force_##chip6, force_##chip7, \
force_##chip8, NULL }; \
I2C_CLIENT_INSMOD_COMMON
#endif /* __KERNEL__ */
#endif /* _LINUX_I2C_H */