/*-
 * Copyright (c) 2004 Nate Lawson (SDG)
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *	notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *	notice, this list of conditions and the following disclaimer in the
 *	documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/bio.h>
#include <sys/bus.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/proc.h>

#include "acpi.h"
#include <dev/acpica/acpivar.h>
#include <dev/fdc/fdcreg.h>
#include <dev/fdc/fdcvar.h>

static int		fdc_acpi_probe(device_t dev);
static int		fdc_acpi_attach(device_t dev);
static ACPI_STATUS	fdc_acpi_probe_child(ACPI_HANDLE h, device_t *dev,
			    int level, void *arg);
static void		fdctl_wr_acpi(fdc_p fdc, u_int8_t v);

/* Parameters for the tape drive (5th device). */
#define ACPI_TAPE_UNKNOWN	0
#define ACPI_TAPE_PRESENT	1
#define ACPI_TAPE_NEVER_PRESENT	2

/* Temporary buf length for evaluating _FDE and _FDI. */
#define ACPI_FDC_BUFLEN		1024

/* Context for walking FDC child devices. */
struct fdc_walk_ctx {
	uint32_t	fd_present[5];
	int		index;
	device_t	acpi_dev;
	device_t	dev;
};

static void
fdctl_wr_acpi(fdc_p fdc, u_int8_t v)
{
	bus_space_write_1(fdc->ctlt, fdc->ctlh, 0, v);
}

static int
fdc_acpi_probe(device_t dev)
{
	device_t bus;
	static char *fdc_ids[] = { "PNP0700", "PNP0701", NULL };

	bus = device_get_parent(dev);
	if (ACPI_ID_PROBE(bus, dev, fdc_ids) == NULL)
		return (ENXIO);

	if (ACPI_SUCCESS(ACPI_EVALUATE_OBJECT(bus, dev, "_FDE", NULL, NULL)))
		device_set_desc(dev, "floppy drive controller (FDE)");
	else
		device_set_desc(dev, "floppy drive controller");
	return (0);
}

static int
fdc_acpi_attach(device_t dev)
{
	struct fdc_walk_ctx *ctx;
	struct fdc_data *sc;
	ACPI_BUFFER buf;
	device_t bus;
	int error, ic_type;
	ACPI_HANDLE h;

	/* Get our softc and use the same accessor as ISA. */
	sc = device_get_softc(dev);
	sc->fdc_dev = dev;
	sc->fdctl_wr = fdctl_wr_acpi;
	sc->flags |= FDC_ISPNP;

	/* Initialize variables and get a temporary buffer for _FDE. */
	error = ENXIO;
	h = acpi_get_handle(dev);
	buf.Length = ACPI_FDC_BUFLEN;
	buf.Pointer = malloc(buf.Length, M_TEMP, M_NOWAIT | M_ZERO);
	if (buf.Pointer == NULL)
		goto out;

	/* Allocate resources the same as the ISA attachment. */
	error = fdc_isa_alloc_resources(dev, sc);
	if (error != 0)
		goto out;

	/* Call common attach code in fdc(4) first. */
	error = fdc_attach(dev);
	if (error != 0)
		goto out;

	/* Check that the controller is working and get its type. */
	error = fdc_initial_reset(sc);
	if (error)
		goto out;
	if (fd_cmd(sc, 1, NE7CMD_VERSION, 1, &ic_type) == 0) {
		ic_type = (u_char)ic_type;
		switch (ic_type) {
		case 0x80:
			sc->fdct = FDC_NE765;
			break;
		case 0x81:	/* not mentioned in any hardware doc */
		case 0x90:
			sc->fdct = FDC_ENHANCED;
			break;
		default:
			sc->fdct = FDC_UNKNOWN;
			break;
		}
	}

	/*
	 * Enumerate _FDE, which lists floppy drives that are present.  If
	 * this fails, fall back to the ISA hints-based probe method.
	 */
	bus = device_get_parent(dev);
	if (ACPI_SUCCESS(ACPI_EVALUATE_OBJECT(bus, dev, "_FDE", NULL, &buf))) {
		/* Setup the context and walk all child devices. */
		ctx = malloc(sizeof(struct fdc_walk_ctx), M_TEMP, M_NOWAIT);
		if (ctx == NULL) {
			device_printf(dev, "no memory for walking children\n");
			goto out;
		}
		bcopy(buf.Pointer, ctx->fd_present, sizeof(ctx->fd_present));
		ctx->index = 0;
		ctx->dev = dev;
		ctx->acpi_dev = bus;
		ACPI_SCAN_CHILDREN(ctx->acpi_dev, dev, 1, fdc_acpi_probe_child,
		    ctx);
		free(ctx, M_TEMP);

		/* Attach any children found during the probe. */
		error = bus_generic_attach(dev);
		if (error != 0)
			goto out;
	} else {
		error = fdc_hints_probe(dev);
		if (error != 0)
			goto out;
	}

out:
	if (buf.Pointer)
		free(buf.Pointer, M_TEMP);
	if (error != 0)
		fdc_release_resources(sc);

	return (error);
}

static ACPI_STATUS
fdc_acpi_probe_child(ACPI_HANDLE h, device_t *dev, int level, void *arg)
{
	struct fdc_walk_ctx *ctx;
	device_t child;
	ACPI_BUFFER buf;
	ACPI_OBJECT *pkg, *obj;
	ACPI_STATUS status;

	/*
	 * The first four ints are booleans that indicate whether fd0-3 are
	 * present or not.  The last is for a tape device, which we don't
	 * bother supporting for now.
	 */
	ctx = (struct fdc_walk_ctx *)arg;
	if (ctx->index > 3)
		return (AE_OK);

	/* Get temporary buffer for _FDI probe. */
	buf.Length = ACPI_FDC_BUFLEN;
	buf.Pointer = malloc(buf.Length, M_TEMP, M_NOWAIT | M_ZERO);
	if (buf.Pointer == NULL)
		goto out;

	/* This device is not present, move on to the next. */
	if (ctx->fd_present[ctx->index] == 0)
		goto out;

	/* Evaluate _FDI to get drive type to pass to the child. */
	status = ACPI_EVALUATE_OBJECT(ctx->acpi_dev, *dev, "_FDI", NULL, &buf);
	if (ACPI_FAILURE(status)) {
		device_printf(ctx->dev, "_FDI not available - %#x\n", status);
		goto out;
	}
	pkg = (ACPI_OBJECT *)buf.Pointer;
	if (!ACPI_PKG_VALID(pkg, 16)) {
		device_printf(ctx->dev, "invalid _FDI package\n");
		goto out;
	}
	obj = &pkg->Package.Elements[1];
	if (obj == NULL || obj->Type != ACPI_TYPE_INTEGER) {
		device_printf(ctx->dev, "invalid type object in _FDI\n");
		goto out;
	}

	/* Create a device for the child with the given index and set ivars. */
	child = fdc_add_child(ctx->dev, "fd", ctx->index);
	if (child == NULL)
		goto out;
	*dev = child;
	fdc_set_fdtype(child, obj->Integer.Value);

out:
	ctx->index++;
	if (buf.Pointer)
		free(buf.Pointer, M_TEMP);
	return (AE_OK);
}

static device_method_t fdc_acpi_methods[] = {
	/* Device interface */
	DEVMETHOD(device_probe,		fdc_acpi_probe),
	DEVMETHOD(device_attach,	fdc_acpi_attach),
	DEVMETHOD(device_detach,	fdc_detach),

	/* Bus interface */
	DEVMETHOD(bus_print_child,	fdc_print_child),
	DEVMETHOD(bus_read_ivar,	fdc_read_ivar),
	DEVMETHOD(bus_write_ivar,	fdc_write_ivar),

	{0, 0}
};

static driver_t fdc_acpi_driver = {
	"fdc",
	fdc_acpi_methods,
	sizeof(struct fdc_data)
};

DRIVER_MODULE(fdc, acpi, fdc_acpi_driver, fdc_devclass, 0, 0);