/*
 *  ide_pc9800.c
 *
 *  Copyright (C) 1997-2000  Linux/98 project,
 *			     Kyoto University Microcomputer Club.
 */

#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/ioport.h>
#include <linux/ide.h>
#include <linux/init.h>

#include <asm/io.h>
#include <asm/pc9800.h>

#define PC9800_IDE_BANKSELECT	0x432

#undef PC9800_IDE_DEBUG

static void pc9800_select(ide_drive_t *drive)
{
#ifdef PC9800_IDE_DEBUG
	byte old;

	/* Too noisy: */
	/* printk(KERN_DEBUG "pc9800_select(%s)\n", drive->name); */

	outb(0x80, PC9800_IDE_BANKSELECT);
	old = inb(PC9800_IDE_BANKSELECT);
	if (old != HWIF(drive)->index)
		printk(KERN_DEBUG "ide-pc9800: switching bank #%d -> #%d\n",
			old, HWIF(drive)->index);
#endif
	outb(HWIF(drive)->index, PC9800_IDE_BANKSELECT);
}

void __init ide_probe_for_pc9800(void)
{
	u8 saved_bank;

	if (!PC9800_9821_P() /* || !PC9821_IDEIF_DOUBLE_P() */)
		return;

	if (!request_region(PC9800_IDE_BANKSELECT, 1, "ide0/1 bank")) {
		printk(KERN_ERR
			"ide: bank select port (%#x) is already occupied!\n",
			PC9800_IDE_BANKSELECT);
		return;
	}

	/* Do actual probing. */
	if ((saved_bank = inb(PC9800_IDE_BANKSELECT)) == (u8) ~0
	    || (outb(saved_bank ^ 1, PC9800_IDE_BANKSELECT),
		/* Next outb is dummy for reading status. */
		outb(0x80, PC9800_IDE_BANKSELECT),
		inb(PC9800_IDE_BANKSELECT) != (saved_bank ^ 1))) {
		printk(KERN_INFO
			"ide: pc9800 type bank selecting port not found\n");
		release_region(PC9800_IDE_BANKSELECT, 1);
		return;
	}

	/* Restore original value, just in case. */
	outb(saved_bank, PC9800_IDE_BANKSELECT);

	/* These ports are reseved by IDE I/F.  */
	if (!request_region(0x430, 1, "ide") ||
	    !request_region(0x435, 1, "ide")) {
		printk(KERN_WARNING
			"ide: IO port 0x430 and 0x435 are reserved for IDE"
			" the card using these ports may not work\n");
	}

	if (ide_hwifs[0].io_ports[IDE_DATA_OFFSET] == HD_DATA &&
	    ide_hwifs[1].io_ports[IDE_DATA_OFFSET] == HD_DATA) {
		ide_hwifs[0].chipset = ide_pc9800;
		ide_hwifs[0].mate = &ide_hwifs[1];
		ide_hwifs[0].selectproc = pc9800_select;
		ide_hwifs[1].chipset = ide_pc9800;
		ide_hwifs[1].mate = &ide_hwifs[0];
		ide_hwifs[1].selectproc = pc9800_select;
	}
}