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

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * altera-lpt.c
   4 *
   5 * altera FPGA driver
   6 *
   7 * Copyright (C) Altera Corporation 1998-2001
   8 * 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