The I2C kernel device drivers provide access to the BCM2835 I2C interface.
In common with many other device drivers it makes 'files' available in the /dev/ folder of your system that you can write to and read from using ioctl commands.
The module HiPi::Device::I2C supports communication with i2c devices using the kernel device driver.
Note that you may also communicate with i2c devices using the userspace bcm2835 library wrapped in HiPi::BCM2835::I2C
The device drivers are configured and loaded at system startup as described in the Loading Device Drivers Topic.
Users who are members of the group 'i2c' can access the I2C devices. By default, user 'pi' is a member of the i2c group.
The Raspberry Pi GPIO provides access to the i2c devices Recent using the device files:
/dev/i2c-1 is the default device available for use. The /dev/i2c-0 is generally reserved for VideoCore and HAT EEPROM.
On early Model B revision 1 boards /dev/i2c-0 is the default device available on the GPIO PAD1 pins.