I2C Device Driver

Modules
	EEPROM Driver
	Driver for EEPROM device.
	GPIO NXP PCA9535 Driver
	Driver for NXP PCA9535 16-bit GPIO device.
	Switch NXP PCA9535 Driver
	Driver for NXP PCA9548A 8-channel switch device.
	Temperature Sensor LM75A Driver
	Driver for NXP or Texas Instruments LM75A temperature sensor.

Files
file	i2c-dev.c
	Inter-Integrated Circuit (I2C) Bus Implementation.

Data Structures
struct	i2c_dev
	I2C slave device control. More...

Macros
#define	I2C_DEV_IO_CONTROL   0x900
	Base number for device IO control commands.

Functions
int	i2c_dev_init (i2c_dev *dev, const char *bus_path, uint16_t address)
	Initializes a device control. More...
i2c_dev *	i2c_dev_alloc_and_init (size_t size, const char *bus_path, uint16_t address)
	Allocates a device control from the heap and initializes it. More...
void	i2c_dev_destroy (i2c_dev *dev)
	Destroys a device control. More...
void	i2c_dev_destroy_and_free (i2c_dev *dev)
	Destroys a device control and frees its memory. More...
int	i2c_dev_register (i2c_dev *dev, const char *dev_path)
	Registers a device control. More...

Detailed Description

Function Documentation

i2c_dev_alloc_and_init()

i2c_dev* i2c_dev_alloc_and_init	(	size_t	size,
		const char *	bus_path,
		uint16_t	address
	)

Allocates a device control from the heap and initializes it.

After a sucessful allocation and initialization the device control must be destroyed via i2c_dev_destroy_and_free(). A registered device control will be automatically destroyed in case the device file is unlinked. Make sure to call i2c_dev_destroy_and_free() in a custom destruction handler.

Parameters

[in]	size	The size of the device control. This enables the addition of device specific data to the base device control. The device control is zero initialized.
[in]	bus_path	The path to the bus device file.
[in]	address	The address of the device.

Return values

non-NULL	The new device control.
NULL	An error occurred. The errno is set to indicate the error.

See also

i2c_dev_register()

i2c_dev_destroy()

void i2c_dev_destroy

(

i2c_dev *

dev

)

Destroys a device control.

Parameters

[in]

dev

The device control.

i2c_dev_destroy_and_free()

void i2c_dev_destroy_and_free

(

i2c_dev *

dev

)

Destroys a device control and frees its memory.

Parameters

[in]

dev

The device control.

i2c_dev_init()

int i2c_dev_init	(	i2c_dev *	dev,
		const char *	bus_path,
		uint16_t	address
	)

Initializes a device control.

After a sucessful initialization the device control must be destroyed via i2c_dev_destroy(). A registered device control will be automatically destroyed in case the device file is unlinked. Make sure to call i2c_dev_destroy_and_free() in a custom destruction handler.

Parameters

[in]	device	The device control.
[in]	bus_path	The path to the bus device file.
[in]	address	The address of the device.

Return values

0	Successful operation.
-1	An error occurred. The errno is set to indicate the error.

See also

i2c_dev_register()

i2c_dev_register()

int i2c_dev_register	(	i2c_dev *	dev,
		const char *	dev_path
	)

Registers a device control.

This function claims ownership of the device control regardless if the registration is successful or not.

Parameters

[in]	dev	The dev control.
[in]	dev_path	The path to the device file of the device.

Return values

0	Successful operation.
-1	An error occurred. The errno is set to indicate the error.