parport_read — read a block of data from a parallel port
ssize_t parport_read ( | struct parport * | port, |
| void * | buffer, | |
| size_t | len); |
portport to read from
bufferdata buffer (in kernel space)
lennumber of bytes of data to transfer
This will read up to len bytes of buffer to the port
specified, using the IEEE 1284 transfer mode most recently
negotiated to (using parport_negotiate), as long as that
mode supports reverse transfers (peripheral to host).
It is the caller's responsibility to ensure that the first
len bytes of buffer are available to write to.
This function returns the number of bytes transferred (if zero or positive), or else an error code.