linux/drivers/misc/altera-stapl/altera-lpt.c

57 lines
1.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* altera-lpt.c
*
* altera FPGA driver
*
* Copyright (C) Altera Corporation 1998-2001
* Copyright (C) 2010 NetUP Inc.
* Copyright (C) 2010 Abylay Ospan <aospan@netup.ru>
*/
#include <linux/io.h>
#include <linux/kernel.h>
#include "altera-exprt.h"
static int lpt_hardware_initialized;
static void byteblaster_write(int port, int data)
{
outb((u8)data, (u16)(port + 0x378));
};
static int byteblaster_read(int port)
{
int data = 0;
data = inb((u16)(port + 0x378));
return data & 0xff;
};
int netup_jtag_io_lpt(void *device, int tms, int tdi, int read_tdo)
{
int data = 0;
int tdo = 0;
int initial_lpt_ctrl = 0;
if (!lpt_hardware_initialized) {
initial_lpt_ctrl = byteblaster_read(2);
byteblaster_write(2, (initial_lpt_ctrl | 0x02) & 0xdf);
lpt_hardware_initialized = 1;
}
data = ((tdi ? 0x40 : 0) | (tms ? 0x02 : 0));
byteblaster_write(0, data);
if (read_tdo) {
tdo = byteblaster_read(1);
tdo = ((tdo & 0x80) ? 0 : 1);
}
byteblaster_write(0, data | 0x01);
byteblaster_write(0, data);
return tdo;
}