1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * (c) 1998  Grant R. Guenther <grant@torque.net>
  4 *
  5 * ktti.c is a low-level protocol driver for the KT Technology
  6 * parallel port adapter.  This adapter is used in the "PHd"
  7 * portable hard-drives.  As far as I can tell, this device
  8 * supports 4-bit mode _only_.
  9*/
 10
 11#include <linux/module.h>
 12#include <linux/init.h>
 13#include <linux/delay.h>
 14#include <linux/kernel.h>
 15#include <linux/types.h>
 16#include <linux/wait.h>
 17#include <asm/io.h>
 18#include "pata_parport.h"
 19
 20#define j44(a, b)	(((a >> 4) & 0x0f) | (b & 0xf0))
 21
 22/*
 23 * cont = 0 - access the IDE register file
 24 * cont = 1 - access the IDE command set
 25 */
 26static int cont_map[2] = { 0x10, 0x08 };
 27
 28static void ktti_write_regr(struct pi_adapter *pi, int cont, int regr, int val)
 29{
 30	int r = regr + cont_map[cont];
 31
 32	w0(r); w2(0xb); w2(0xa); w2(3); w2(6);
 33	w0(val); w2(3); w0(0); w2(6); w2(0xb);
 34}
 35
 36static int ktti_read_regr(struct pi_adapter *pi, int cont, int regr)
 37{
 38	int a, b, r;
 39
 40        r = regr + cont_map[cont];
 41
 42	w0(r); w2(0xb); w2(0xa); w2(9); w2(0xc); w2(9);
 43	a = r1(); w2(0xc);  b = r1(); w2(9); w2(0xc); w2(9);
 44	return j44(a, b);
 45}
 46
 47static void ktti_read_block(struct pi_adapter *pi, char *buf, int count)
 48{
 49	int k, a, b;
 50
 51	for (k = 0; k < count / 2; k++) {
 52		w0(0x10); w2(0xb); w2(0xa); w2(9); w2(0xc); w2(9);
 53		a = r1(); w2(0xc); b = r1(); w2(9);
 54		buf[2*k] = j44(a, b);
 55		a = r1(); w2(0xc); b = r1(); w2(9);
 56		buf[2*k+1] = j44(a, b);
 57	}
 58}
 59
 60static void ktti_write_block(struct pi_adapter *pi, char *buf, int count)
 61{
 62	int k;
 63
 64	for (k = 0; k < count / 2; k++) {
 65		w0(0x10); w2(0xb); w2(0xa); w2(3); w2(6);
 66		w0(buf[2 * k]); w2(3);
 67		w0(buf[2 * k + 1]); w2(6);
 68		w2(0xb);
 69	}
 70}
 71
 72static void ktti_connect(struct pi_adapter *pi)
 73{
 74	pi->saved_r0 = r0();
 75	pi->saved_r2 = r2();
 76	w2(0xb); w2(0xa); w0(0); w2(3); w2(6);
 77}
 78
 79static void ktti_disconnect(struct pi_adapter *pi)
 80{
 81	w2(0xb); w2(0xa); w0(0xa0); w2(3); w2(4);
 82	w0(pi->saved_r0);
 83	w2(pi->saved_r2);
 84}
 85
 86static void ktti_log_adapter(struct pi_adapter *pi)
 87{
 88	dev_info(&pi->dev, "KT adapter at 0x%x, delay %d\n",
 89		 pi->port, pi->delay);
 90}
 91
 92static struct pi_protocol ktti = {
 93	.owner		= THIS_MODULE,
 94	.name		= "ktti",
 95	.max_mode	= 1,
 96	.epp_first	= 2,
 97	.default_delay	= 1,
 98	.max_units	= 1,
 99	.write_regr	= ktti_write_regr,
100	.read_regr	= ktti_read_regr,
101	.write_block	= ktti_write_block,
102	.read_block	= ktti_read_block,
103	.connect	= ktti_connect,
104	.disconnect	= ktti_disconnect,
105	.log_adapter	= ktti_log_adapter,
106};
107
108MODULE_LICENSE("GPL");
109MODULE_AUTHOR("Grant R. Guenther <grant@torque.net>");
110MODULE_DESCRIPTION("KT Technology parallel port IDE adapter protocol driver");
111module_pata_parport_driver(ktti);