path: root/drivers/pnp/isapnp/core.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  ISA Plug & Play support
 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
 *
 *  Changelog:
 *  2000-01-01	Added quirks handling for buggy hardware
 *		Peter Denison <peterd@pnd-pc.demon.co.uk>
 *  2000-06-14	Added isapnp_probe_devs() and isapnp_activate_dev()
 *		Christoph Hellwig <hch@infradead.org>
 *  2001-06-03  Added release_region calls to correspond with
 *		request_region calls when a failure occurs.  Also
 *		added KERN_* constants to printk() calls.
 *  2001-11-07  Added isapnp_{,un}register_driver calls along the lines
 *              of the pci driver interface
 *              Kai Germaschewski <kai.germaschewski@gmx.de>
 *  2002-06-06  Made the use of dma channel 0 configurable
 *              Gerald Teschl <gerald.teschl@univie.ac.at>
 *  2002-10-06  Ported to PnP Layer - Adam Belay <ambx1@neo.rr.com>
 *  2003-08-11	Resource Management Updates - Adam Belay <ambx1@neo.rr.com>
 */

#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/isapnp.h>
#include <linux/mutex.h>
#include <asm/io.h>

#include "../base.h"

#if 0
#define ISAPNP_REGION_OK
#endif

int isapnp_disable;		/* Disable ISA PnP */
static int isapnp_rdp;		/* Read Data Port */
static int isapnp_reset = 1;	/* reset all PnP cards (deactivate) */
static int isapnp_verbose = 1;	/* verbose mode */

module_param(isapnp_disable, int, 0);
MODULE_PARM_DESC(isapnp_disable, "ISA Plug & Play disable");
module_param(isapnp_rdp, int, 0);
MODULE_PARM_DESC(isapnp_rdp, "ISA Plug & Play read data port");
module_param(isapnp_reset, int, 0);
MODULE_PARM_DESC(isapnp_reset, "ISA Plug & Play reset all cards");
module_param(isapnp_verbose, int, 0);
MODULE_PARM_DESC(isapnp_verbose, "ISA Plug & Play verbose mode");

#define _PIDXR		0x279
#define _PNPWRP		0xa79

/* short tags */
#define _STAG_PNPVERNO		0x01
#define _STAG_LOGDEVID		0x02
#define _STAG_COMPATDEVID	0x03
#define _STAG_IRQ		0x04
#define _STAG_DMA		0x05
#define _STAG_STARTDEP		0x06
#define _STAG_ENDDEP		0x07
#define _STAG_IOPORT		0x08
#define _STAG_FIXEDIO		0x09
#define _STAG_VENDOR		0x0e
#define _STAG_END		0x0f
/* long tags */
#define _LTAG_MEMRANGE		0x81
#define _LTAG_ANSISTR		0x82
#define _LTAG_UNICODESTR	0x83
#define _LTAG_VENDOR		0x84
#define _LTAG_MEM32RANGE	0x85
#define _LTAG_FIXEDMEM32RANGE	0x86

/* Logical device control and configuration registers */

#define ISAPNP_CFG_ACTIVATE	0x30	/* byte */
#define ISAPNP_CFG_MEM		0x40	/* 4 * dword */
#define ISAPNP_CFG_PORT		0x60	/* 8 * word */
#define ISAPNP_CFG_IRQ		0x70	/* 2 * word */
#define ISAPNP_CFG_DMA		0x74	/* 2 * byte */

/*
 * Sizes of ISAPNP logical device configuration register sets.
 * See PNP-ISA-v1.0a.pdf, Appendix A.
 */
#define ISAPNP_MAX_MEM		4
#define ISAPNP_MAX_PORT		8
#define ISAPNP_MAX_IRQ		2
#define ISAPNP_MAX_DMA		2

static unsigned char isapnp_checksum_value;
static DEFINE_MUTEX(isapnp_cfg_mutex);
static int isapnp_csn_count;

/* some prototypes */

static inline void write_data(unsigned char x)
{
	outb(x, _PNPWRP);
}

static inline void write_address(unsigned char x)
{
	outb(x, _PIDXR);
	udelay(20);
}

static inline unsigned char read_data(void)
{
	unsigned char val = inb(isapnp_rdp);
	return val;
}

unsigned char isapnp_read_byte(unsigned char idx)
{
	write_address(idx);
	return read_data();
}

static unsigned short isapnp_read_word(unsigned char idx)
{
	unsigned short val;

	val = isapnp_read_byte(idx);
	val = (val << 8) + isapnp_read_byte(idx + 1);
	return val;
}

void isapnp_write_byte(unsigned char idx, unsigned char val)
{
	write_address(idx);
	write_data(val);
}

static void isapnp_write_word(unsigned char idx, unsigned short val)
{
	isapnp_write_byte(idx, val >> 8);
	isapnp_write_byte(idx + 1, val);
}

static void isapnp_key(void)
{
	unsigned char code = 0x6a, msb;
	int i;

	mdelay(1);
	write_address(0x00);
	write_address(0x00);

	write_address(code);

	for (i = 1; i < 32; i++) {
		msb = ((code & 0x01) ^ ((code & 0x02) >> 1)) << 7;
		code = (code >> 1) | msb;
		write_address(code);
	}
}

/* place all pnp cards in wait-for-key state */
static void isapnp_wait(void)
{
	isapnp_write_byte(0x02, 0x02);
}

static void isapnp_wake(unsigned char csn)
{
	isapnp_write_byte(0x03, csn);
}

static void isapnp_device(unsigned char logdev)
{
	isapnp_write_byte(0x07, logdev);
}

static void isapnp_activate(unsigned char logdev)
{
	isapnp_device(logdev);
	isapnp_write_byte(ISAPNP_CFG_ACTIVATE, 1);
	udelay(250);
}

static void isapnp_deactivate(unsigned char logdev)
{
	isapnp_device(logdev);
	isapnp_write_byte(ISAPNP_CFG_ACTIVATE, 0);
	udelay(500);
}

static void __init isapnp_peek(unsigned char *data, int bytes)
{
	int i, j;
	unsigned char d = 0;

	for (i = 1; i <= bytes; i++) {
		for (j = 0; j < 20; j++) {
			d = isapnp_read_byte(0x05);
			if (d & 1)
				break;
			udelay(100);
		}
		if (!(d & 1)) {
			if (data != NULL)
				*data++ = 0xff;
			continue;
		}
		d