Исследование драйвера ядра Linux для шины I2C

  244     struct list_head clients;

  245     struct list_head list;

  246     char name[I2C_NAME_SIZE];

  247     struct completion dev_released;

  248     struct completion class_dev_released;

  249 };

  250 #define dev_to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)

  251 #define class_dev_to_i2c_adapter(d) container_of(d, struct i2c_adapter,

  252                                  class_dev)

  253

  254 static inline void *i2c_get_adapdata (struct i2c_adapter *dev)

  255 {

  256     return dev_get_drvdata (&dev->dev);

  257 }

  258

  259 static inline void i2c_set_adapdata (struct i2c_adapter *dev, void *data)

  260 {

  261     dev_set_drvdata (&dev->dev, data);

  262 }

  263

  264 /*flags for the driver struct: */

  265 #define I2C_DF_NOTIFY   0x01        /* notify on bus (de/a)ttaches  */

  266 #if 0

  267 /* this flag is gone -- there is a (optional) driver->detach_adapter

  268 * callback now which can be used instead */

  269 # define I2C_DF_DUMMY   0x02

  270 #endif

  271

  272 /*flags for the client struct: */

  273 #define I2C_CLIENT_ALLOW_USE        0x01    /* Client allows access */

  274 #define I2C_CLIENT_ALLOW_MULTIPLE_USE   0x02    /* Allow multiple access-

  275 locks */

  276                         /* on an i2c_client */

  277 #define I2C_CLIENT_PEC  0x04            /* Use Packet Error Checking */

  278 #define I2C_CLIENT_TEN  0x10            /* we have a ten bit chip address

  279 */

  280                         /* Must equal I2C_M_TEN below */

  281

  282 /* i2c adapter classes (bitmask) */

  283 #define I2C_CLASS_HWMON     (1<<0)  /* lm_sensors, ... */

  284 #define I2C_CLASS_TV_ANALOG (1<<1)  /* bttv + friends */

  285 #define I2C_CLASS_TV_DIGITAL    (1<<2)  /* dvb cards */

  286 #define I2C_CLASS_DDC       (1<<3)  /* i2c-matroxfb ? */

  287 #define I2C_CLASS_CAM_ANALOG    (1<<4)  /* camera with analog CCD */

  288 #define I2C_CLASS_CAM_DIGITAL   (1<<5)  /* most webcams */

  289 #define I2C_CLASS_SOUND     (1<<6)  /* sound devices */

  290 #define I2C_CLASS_ALL       (UINT_MAX) /* all of the above */

  291

  292 /* i2c_client_address_data is the struct for holding default client

  293 * addresses for a driver and for the parameters supplied on the

  294 * command line

  295 */

  296 struct i2c_client_address_data {

  297     unsigned short *normal_i2c;

  298     unsigned short *probe;

  299     unsigned short *ignore;

  300     unsigned short **forces;

  301 };

  302

  303 /* Internal numbers to terminate lists */

  304 #define I2C_CLIENT_END      0xfffeU

  305

  306 /* The numbers to use to set I2C bus address */

  307 #define ANY_I2C_BUS     0xffff

  308 #define ANY_I2C_ISA_BUS     9191

  309

  310

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

  312

  313 /* administration...

  314 */

  315 extern int i2c_add_adapter(struct i2c_adapter *);

  316 extern int i2c_del_adapter(struct i2c_adapter *);

  317

  318 extern int i2c_add_driver(struct i2c_driver *);

  319 extern int i2c_del_driver(struct i2c_driver *);

  320

  321 extern int i2c_attach_client(struct i2c_client *);

  322 extern int i2c_detach_client(struct i2c_client *);

  323

  324 /* New function: This is to get an i2c_client-struct for controlling the

  325    client either by using i2c_control-function or having the

  326    client-module export functions that can be used with the i2c_client

  327    -struct. */

  328 extern struct i2c_client *i2c_get_client(int driver_id, int adapter_id,

  329                     struct i2c_client *prev);

  330

  331 /* Should be used with new function

  332    extern struct i2c_client *i2c_get_client(int,int,struct i2c_client *);

  333    to make sure that client-struct is valid and that it is okay to access

  334    the i2c-client.

  335    returns -EACCES if client doesn't allow use (default)

  336    returns -EBUSY if client doesn't allow multiple use (default) and

  337    usage_count >0 */

  338 extern int i2c_use_client(struct i2c_client *);

  339 extern int i2c_release_client(struct i2c_client *);

  340

  341 /* call the i2c_client->command() of all attached clients with

  342 * the given arguments */

  343 extern void i2c_clients_command(struct i2c_adapter *adap,

  344                 unsigned int cmd, void *arg);

  345

  346 /* returns -EBUSY if address has been taken, 0 if not. Note that the only

  347    other place at which this is called is within i2c_attach_client; so

  348    you can cheat by simply not registering. Not recommended, of course! */

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

  350

  351 /* Detect function. It iterates over all possible addresses itself.

  352 * It will only call found_proc if some client is connected at the

  353 * specific address (unless a 'force' matched);

  354 */

  355 extern int i2c_probe(struct i2c_adapter *adapter,

  356         struct i2c_client_address_data *address_data,

  357         int (*found_proc) (struct i2c_adapter *, int, int));

  358

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

  360 */

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

  362

  363 extern struct i2c_adapter* i2c_get_adapter(int id);

  364 extern void i2c_put_adapter(struct i2c_adapter *adap);

  365

  366

  367 /* Return the functionality mask */

  368 static inline u32 i2c_get_functionality(struct i2c_adapter *adap)

  369 {

  370     return adap->algo->functionality(adap);

  371 }

  372

  373 /* Return 1 if adapter supports everything we need, 0 if not. */

  374 static inline int i2c_check_functionality(struct i2c_adapter *adap, u32

  375                                           func)

  376 {

  377     return (func & i2c_get_functionality(adap)) == func;

  378 }

  379

  380 /* Return id number for a specific adapter */

  381 static inline int i2c_adapter_id(struct i2c_adapter *adap)

  382 {

  383     return adap->nr;

  384 }

  385

  386 /*

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

  388 */

  389 struct i2c_msg {

  390     __u16 addr; /* slave address            */

  391     __u16 flags;

  392 #define I2C_M_TEN   0x10    /* we have a ten bit chip address   */

  393 #define I2C_M_RD    0x01