path: root/sys/dev/dpms/dpms.c

/*-
 * Copyright (c) 2008 Yahoo!, Inc.
 * All rights reserved.
 * Written by: John Baldwin <jhb@FreeBSD.org>
 *
 * 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.
 * 3. Neither the name of the author nor the names of any co-contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * 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.
 */

/*
 * Copyright (c) 2004 Benjamin Close <Benjamin.Close@clearchain.com>
 * 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.
 */

/*
 * Support for managing the display via DPMS for suspend/resume.
 */

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

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/libkern.h>
#include <sys/module.h>

#include <vm/vm.h>
#include <vm/pmap.h>

#include <contrib/x86emu/x86emu.h>
#include <contrib/x86emu/x86emu_regs.h>

/*
 * VESA DPMS States 
 */
#define DPMS_ON		0x00
#define DPMS_STANDBY	0x01
#define DPMS_SUSPEND	0x02
#define DPMS_OFF	0x04
#define DPMS_REDUCEDON	0x08

#define	VBE_DPMS_FUNCTION	0x4F10
#define	VBE_DPMS_GET_SUPPORTED_STATES 0x00
#define	VBE_DPMS_GET_STATE	0x02
#define	VBE_DPMS_SET_STATE	0x01
#define VBE_MAJORVERSION_MASK	0x0F
#define VBE_MINORVERSION_MASK	0xF0

struct dpms_softc {
	int	dpms_supported_states;
	int	dpms_initial_state;
};

static struct x86emu vesa_emu;
static unsigned char *emumem = NULL;

static int	dpms_attach(device_t);
static int	dpms_detach(device_t);
static int	dpms_get_supported_states(int *);
static int	dpms_get_current_state(int *);
static void	dpms_identify(driver_t *, device_t);
static int	dpms_probe(device_t);
static int	dpms_resume(device_t);
static int	dpms_set_state(int);
static int	dpms_suspend(device_t);

static device_method_t dpms_methods[] = {
	DEVMETHOD(device_identify,	dpms_identify),
	DEVMETHOD(device_probe,		dpms_probe),
	DEVMETHOD(device_attach,	dpms_attach),
	DEVMETHOD(device_detach,	dpms_detach),
	DEVMETHOD(device_suspend,	dpms_suspend),
	DEVMETHOD(device_resume,	dpms_resume),
	{ 0, 0 }
};

static driver_t dpms_driver = {
	"dpms",
	dpms_methods,
	sizeof(struct dpms_softc),
};

static devclass_t dpms_devclass;

DRIVER_MODULE(dpms, vgapci, dpms_driver, dpms_devclass, NULL, NULL);
MODULE_DEPEND(dpms, x86emu, 1, 1, 1);

static uint8_t
vm86_emu_inb(struct x86emu *emu, uint16_t port)
{
	if (port == 0xb2) /* APM scratch register */
		return 0;
	if (port >= 0x80 && port < 0x88) /* POST status register */
		return 0;
	return inb(port);
}

static uint16_t
vm86_emu_inw(struct x86emu *emu, uint16_t port)
{
	if (port >= 0x80 && port < 0x88) /* POST status register */
		return 0;
	return inw(port);
}

static uint32_t
vm86_emu_inl(struct x86emu *emu, uint16_t port)
{
	if (port >= 0x80 && port < 0x88) /* POST status register */
		return 0;
	return inl(port);
}

static void
vm86_emu_outb(struct x86emu *emu, uint16_t port, uint8_t val)
{
	if (port == 0xb2) /* APM scratch register */
		return;
	if (port >= 0x80 && port < 0x88) /* POST status register */
		return;
	outb(port, val);
}

static void
vm86_emu_outw(struct x86emu *emu, uint16_t port, uint16_t val)
{
	if (port >= 0x80 && port < 0x88) /* POST status register */
		return;
	outw(port, val);
}

static void
vm86_emu_outl(struct x86emu *emu, uint16_t port, uint32_t val)
{
	if (port >= 0x80 && port < 0x88) /* POST status register */
		return;
	outl(port, val);
}

static void
dpms_identify(driver_t *driver, device_t parent)
{

	/*
	 * XXX: The DPMS VBE only allows for manipulating a single
	 * monitor, but we don't know which one.  Just attach to the
	 * first vgapci(4) device we encounter and hope it is the
	 * right one.
	 */
	if (devclass_get_device(dpms_devclass, 0) == NULL)
		device_add_child(parent, "dpms", 0);

}

static int
dpms_probe(device_t dev)
{
	int error, states;

	emumem = pmap_mapbios(0x0, 0xc00000);

	memset(&vesa_emu, 0, sizeof(vesa_emu));
	x86emu_init_default(&vesa_emu);

	vesa_emu.emu_inb = vm86_emu_inb;
	vesa_emu.emu_inw = vm86_emu_inw;
	vesa_emu.emu_inl = vm86_emu_inl;
	vesa_emu.emu_outb = vm86_emu_outb;
	vesa_emu.emu_outw = vm86_emu_outw;
	vesa_emu.emu_outl = vm86_emu_outl;

	vesa_emu.mem_base = (char *)emumem;
	vesa_emu.mem_size = 1024 * 1024;

	error = dpms_get_supported_states(&states);
	if (error)
		return (error);
	device_set_desc(dev, "DPMS suspend/resume");
	device_quiet(dev);
	return (BUS_PROBE_DEFAULT);
}

static int
dpms_attach(device_t dev)
{
	struct dpms_softc *sc;
	int error;

	sc = device_get_softc(dev);
	error = dpms_get_supported_states(&sc->dpms_supported_states);
	if (error)
		return (error);
	error = dpms_get_current_state(&sc->dpms_initial_state);
	return (error);
}

static int
dpms_detach(device_t dev)
{
	if (emumem)
		pmap_unmapdev((vm_offset_t)emumem, 0xc00000);

	return (0);
}

static int
dpms_suspend(device_t dev)
{

	dpms_set_state(DPMS_OFF);
	return (0);
}

static int
dpms_resume(device_t dev)
{
	struct dpms_softc *sc;

	sc = device_get_softc(dev);
	dpms_set_state(sc->dpms_initial_state);
	return (0);
}

static int
dpms_call_bios(int subfunction, int *bh)
{
	vesa_emu.x86.R_AX = VBE_DPMS_FUNCTION;
	vesa_emu.x86.R_BL = subfunction;
	vesa_emu.x86.R_BH = *bh;
	vesa_emu.x86.R_ES = 0;
	vesa_emu.x86.R_DI = 0;
	x86emu_exec_intr(&vesa_emu, 0x10);

	if ((vesa_emu.x86.R_EAX & 0xffff) != 0x004f)
		return (ENXIO);

	*bh = vesa_emu.x86.R_BH;

	return (0);
}

static int
dpms_get_supported_states(int *states)
{

	*states = 0;
	return (dpms_call_bios(VBE_DPMS_GET_SUPPORTED_STATES, states));
}

static int
dpms_get_current_state(int *state)
{

	*state = 0;
	return (dpms_call_bios(VBE_DPMS_GET_STATE, state));
}

static int
dpms_set_state(int state)
{

	return (dpms_call_bios(VBE_DPMS_SET_STATE, &state));
}