bitbash.c File Reference

Bit-bashing interfaces. More...

#include <ipxe/bitbash.h>

Go to the source code of this file.

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
	FILE_SECBOOT (PERMITTED)
void	write_bit (struct bit_basher *basher, unsigned int bit_id, unsigned long data)
	Set/clear output bit.
int	read_bit (struct bit_basher *basher, unsigned int bit_id)
	Read input bit.

Detailed Description

Bit-bashing interfaces.

Definition in file bitbash.c.

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

FILE_SECBOOT()

FILE_SECBOOT

(

PERMITTED

)

write_bit()

void write_bit	(	struct bit_basher *	basher,
		unsigned int	bit_id,
		unsigned long	data )

Set/clear output bit.

Parameters

basher	Bit-bashing interface
bit_id	Bit number
data	Value to write

If data is 0, a logic 0 will be written. If data is non-zero, a logic 1 will be written.

Definition at line 45 of file bitbash.c.

                                      {
        basher->op->write ( basher, bit_id, ( data ? -1UL : 0 ) );
}

References data, bit_basher::op, and bit_basher_operations::write.

Referenced by mii_bit_rw(), mii_bit_xfer(), setscl(), setsda(), spi_bit_rw(), spi_bit_set_slave_select(), and spi_bit_transfer().

read_bit()

int read_bit	(	struct bit_basher *	basher,
		unsigned int	bit_id )

Read input bit.

Parameters

basher	Bit-bashing interface
bit_id	Bit number

Return values

data	Value read

data will always be either 0 or -1UL. The idea is that the caller can simply binary-AND the returned value with whatever mask it needs to apply.

Definition at line 61 of file bitbash.c.

                                                                {
        return ( basher->op->read ( basher, bit_id ) ? -1UL : 0 );
}

References bit_basher::op, and bit_basher_operations::read.

Referenced by getsda(), mii_bit_xfer(), and spi_bit_transfer().