/* Test if the peripheral is IEEE 1284 compliant.
* return values are:
* 0 - handshake failed; peripheral is not compliant (or none present)
* 1 - handshake OK; IEEE1284 peripheral present but no data available
* 2 - handshake OK; IEEE1284 peripheral and data available
*/
int parport_ieee1284_nibble_mode_ok(struct parport *port, unsigned char mode)
{
/* make sure it's a valid state, set nStrobe & nAutoFeed high */
parport_write_control(port, (parport_read_control(port) \
& ~1 ) & ~2);
udelay(1);
parport_write_data(port, mode);
udelay(1);
/* nSelectIn high, nAutoFd low */
parport_write_control(port, (parport_read_control(port) & ~8) | 2);
if (parport_wait_peripheral(port, 0x78, 0x38)) {
parport_write_control(port,
(parport_read_control(port) & ~2) | 8);
return 0;
}
/* nStrobe low */
parport_write_control(port, parport_read_control(port) | 1);
udelay(1); /* Strobe wait */
/* nStrobe high, nAutoFeed low, last step before transferring
* reverse data */
parport_write_control(port, (parport_read_control(port) \
& ~1) & ~2);
udelay(1);
/* Data available? */
return (parport_wait_peripheral(port, 0x20, 0))?1:2;
}
static void bit_lp_setscl(void *data, int state)
{
/*be cautious about state of the control register -
touch only the one bit needed*/
if (state) {
parport_write_control((struct parport *) data,
parport_read_control((struct parport *) data)|I2C_SCL);
} else {
parport_write_control((struct parport *) data,
parport_read_control((struct parport *) data)&I2C_CMASK);
}
}
static unsigned int in(int offset)
{
switch (offset) {
case LIRC_LP_BASE:
return parport_read_data(pport);
case LIRC_LP_STATUS:
return parport_read_status(pport);
case LIRC_LP_CONTROL:
return parport_read_control(pport);
}
return 0; /* make compiler happy */
}
static unsigned char port_read_control(struct parport *p)
{
return parport_read_control(p);
}
