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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * altera-lpt.c4 *5 * altera FPGA driver6 *7 * Copyright (C) Altera Corporation 1998-20018 * Copyright (C) 2010 NetUP Inc.9 * Copyright (C) 2010 Abylay Ospan <aospan@netup.ru>10 */11 12#include <linux/io.h>13#include <linux/kernel.h>14#include "altera-exprt.h"15 16static int lpt_hardware_initialized;17 18static void byteblaster_write(int port, int data)19{20 outb((u8)data, (u16)(port + 0x378));21};22 23static int byteblaster_read(int port)24{25 int data = 0;26 data = inb((u16)(port + 0x378));27 return data & 0xff;28};29 30int netup_jtag_io_lpt(void *device, int tms, int tdi, int read_tdo)31{32 int data = 0;33 int tdo = 0;34 int initial_lpt_ctrl = 0;35 36 if (!lpt_hardware_initialized) {37 initial_lpt_ctrl = byteblaster_read(2);38 byteblaster_write(2, (initial_lpt_ctrl | 0x02) & 0xdf);39 lpt_hardware_initialized = 1;40 }41 42 data = ((tdi ? 0x40 : 0) | (tms ? 0x02 : 0));43 44 byteblaster_write(0, data);45 46 if (read_tdo) {47 tdo = byteblaster_read(1);48 tdo = ((tdo & 0x80) ? 0 : 1);49 }50 51 byteblaster_write(0, data | 0x01);52 53 byteblaster_write(0, data);54 55 return tdo;56}57