[deliverable/linux.git] / drivers / platform / x86 / apple-gmux.c

/*
 *  Gmux driver for Apple laptops
 *
 *  Copyright (C) Canonical Ltd. <seth.forshee@canonical.com>
 *  Copyright (C) 2010-2012 Andreas Heider <andreas@meetr.de>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/backlight.h>
#include <linux/acpi.h>
#include <linux/pnp.h>
#include <linux/apple_bl.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/pci.h>
#include <linux/vga_switcheroo.h>
#include <acpi/video.h>
#include <asm/io.h>

struct apple_gmux_data {
	unsigned long iostart;
	unsigned long iolen;
	bool indexed;
	struct mutex index_lock;

	struct backlight_device *bdev;

	/* switcheroo data */
	acpi_handle dhandle;
	int gpe;
	enum vga_switcheroo_client_id resume_client_id;
	enum vga_switcheroo_state power_state;
	struct completion powerchange_done;
};

static struct apple_gmux_data *apple_gmux_data;

/*
 * gmux port offsets. Many of these are not yet used, but may be in the
 * future, and it's useful to have them documented here anyhow.
 */
#define GMUX_PORT_VERSION_MAJOR		0x04
#define GMUX_PORT_VERSION_MINOR		0x05
#define GMUX_PORT_VERSION_RELEASE	0x06
#define GMUX_PORT_SWITCH_DISPLAY	0x10
#define GMUX_PORT_SWITCH_GET_DISPLAY	0x11
#define GMUX_PORT_INTERRUPT_ENABLE	0x14
#define GMUX_PORT_INTERRUPT_STATUS	0x16
#define GMUX_PORT_SWITCH_DDC		0x28
#define GMUX_PORT_SWITCH_EXTERNAL	0x40
#define GMUX_PORT_SWITCH_GET_EXTERNAL	0x41
#define GMUX_PORT_DISCRETE_POWER	0x50
#define GMUX_PORT_MAX_BRIGHTNESS	0x70
#define GMUX_PORT_BRIGHTNESS		0x74
#define GMUX_PORT_VALUE			0xc2
#define GMUX_PORT_READ			0xd0
#define GMUX_PORT_WRITE			0xd4

#define GMUX_MIN_IO_LEN			(GMUX_PORT_BRIGHTNESS + 4)

#define GMUX_INTERRUPT_ENABLE		0xff
#define GMUX_INTERRUPT_DISABLE		0x00

#define GMUX_INTERRUPT_STATUS_ACTIVE	0
#define GMUX_INTERRUPT_STATUS_DISPLAY	(1 << 0)
#define GMUX_INTERRUPT_STATUS_POWER	(1 << 2)
#define GMUX_INTERRUPT_STATUS_HOTPLUG	(1 << 3)

#define GMUX_BRIGHTNESS_MASK		0x00ffffff
#define GMUX_MAX_BRIGHTNESS		GMUX_BRIGHTNESS_MASK

static u8 gmux_pio_read8(struct apple_gmux_data *gmux_data, int port)
{
	return inb(gmux_data->iostart + port);
}

static void gmux_pio_write8(struct apple_gmux_data *gmux_data, int port,
			       u8 val)
{
	outb(val, gmux_data->iostart + port);
}

static u32 gmux_pio_read32(struct apple_gmux_data *gmux_data, int port)
{
	return inl(gmux_data->iostart + port);
}

static void gmux_pio_write32(struct apple_gmux_data *gmux_data, int port,
			     u32 val)
{
	int i;
	u8 tmpval;

	for (i = 0; i < 4; i++) {
		tmpval = (val >> (i * 8)) & 0xff;
		outb(tmpval, port + i);
	}
}

static int gmux_index_wait_ready(struct apple_gmux_data *gmux_data)
{
	int i = 200;
	u8 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);

	while (i && (gwr & 0x01)) {
		inb(gmux_data->iostart + GMUX_PORT_READ);
		gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
		udelay(100);
		i--;
	}

	return !!i;
}

static int gmux_index_wait_complete(struct apple_gmux_data *gmux_data)
{
	int i = 200;
	u8 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);

	while (i && !(gwr & 0x01)) {
		gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
		udelay(100);
		i--;
	}

	if (gwr & 0x01)
		inb(gmux_data->iostart + GMUX_PORT_READ);

	return !!i;
}

static u8 gmux_index_read8(struct apple_gmux_data *gmux_data, int port)
{
	u8 val;

	mutex_lock(&gmux_data->index_lock);
	outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ);
	gmux_index_wait_ready(gmux_data);
	val = inb(gmux_data->iostart + GMUX_PORT_VALUE);
	mutex_unlock(&gmux_data->index_lock);

	return val;
}

static void gmux_index_write8(struct apple_gmux_data *gmux_data, int port,
			      u8 val)
{
	mutex_lock(&gmux_data->index_lock);
	outb(val, gmux_data->iostart + GMUX_PORT_VALUE);
	gmux_index_wait_ready(gmux_data);
	outb(port & 0xff, gmux_data->iostart + GMUX_PORT_WRITE);
	gmux_index_wait_complete(gmux_data);
	mutex_unlock(&gmux_data->index_lock);
}

static u32 gmux_index_read32(struct apple_gmux_data *gmux_data, int port)
{
	u32 val;

	mutex_lock(&gmux_data->index_lock);
	outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ);
	gmux_index_wait_ready(gmux_data);
	val = inl(gmux_data->iostart + GMUX_PORT_VALUE);
	mutex_unlock(&gmux_data->index_lock);

	return val;
}

static void gmux_index_write32(struct apple_gmux_data *gmux_data, int port,
			       u32 val)
{
	int i;
	u8 tmpval;

	mutex_lock(&gmux_data->index_lock);

	for (i = 0; i < 4; i++) {
		tmpval = (val >> (i * 8)) & 0xff;
		outb(tmpval, gmux_data->iostart + GMUX_PORT_VALUE + i);
	}

	gmux_index_wait_ready(gmux_data);
	outb(port & 0xff, gmux_data->iostart + GMUX_PORT_WRITE);
	gmux_index_wait_complete(gmux_data);
	mutex_unlock(&gmux_data->index_lock);
}

static u8 gmux_read8(struct apple_gmux_data *gmux_data, int port)
{
	if (gmux_data->indexed)
		return gmux_index_read8(gmux_data, port);
	else
		return gmux_pio_read8(gmux_data, port);
}

static void gmux_write8(struct apple_gmux_data *gmux_data, int port, u8 val)
{
	if (gmux_data->indexed)
		gmux_index_write8(gmux_data, port, val);
	else
		gmux_pio_write8(gmux_data, port, val);
}

static u32 gmux_read32(struct apple_gmux_data *gmux_data, int port)
{
	if (gmux_data->indexed)
		return gmux_index_read32(gmux_data, port);
	else
		return gmux_pio_read32(gmux_data, port);
}

static void gmux_write32(struct apple_gmux_data *gmux_data, int port,
			     u32 val)
{
	if (gmux_data->indexed)
		gmux_index_write32(gmux_data, port, val);
	else
		gmux_pio_write32(gmux_data, port, val);
}

static bool gmux_is_indexed(struct apple_gmux_data *gmux_data)
{
	u16 val;

	outb(0xaa, gmux_data->iostart + 0xcc);
	outb(0x55, gmux_data->iostart + 0xcd);
	outb(0x00, gmux_data->iostart + 0xce);

	val = inb(gmux_data->iostart + 0xcc) |
		(inb(gmux_data->iostart + 0xcd) << 8);

	if (val == 0x55aa)
		return true;

	return false;
}

static int gmux_get_brightness(struct backlight_device *bd)
{
	struct apple_gmux_data *gmux_data = bl_get_data(bd);
	return gmux_read32(gmux_data, GMUX_PORT_BRIGHTNESS) &
	       GMUX_BRIGHTNESS_MASK;
}

static int gmux_update_status(struct backlight_device *bd)
{
	struct apple_gmux_data *gmux_data = bl_get_data(bd);
	u32 brightness = bd->props.brightness;

	if (bd->props.state & BL_CORE_SUSPENDED)
		return 0;

	gmux_write32(gmux_data, GMUX_PORT_BRIGHTNESS, brightness);

	return 0;
}

static const struct backlight_ops gmux_bl_ops = {
	.options = BL_CORE_SUSPENDRESUME,
	.get_brightness = gmux_get_brightness,
	.update_status = gmux_update_status,
};

static int gmux_switchto(enum vga_switcheroo_client_id id)
{
	if (id == VGA_SWITCHEROO_IGD) {
		gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DDC, 1);
		gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DISPLAY, 2);
		gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_EXTERNAL, 2);
	} else {
		gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DDC, 2);
		gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DISPLAY, 3);
		gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_EXTERNAL, 3);
	}

	return 0;
}

static int gmux_set_discrete_state(struct apple_gmux_data *gmux_data,
				   enum vga_switcheroo_state state)
{
	INIT_COMPLETION(gmux_data->powerchange_done);

	if (state == VGA_SWITCHEROO_ON) {
		gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 1);
		gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 3);
		pr_debug("Discrete card powered up\n");
	} else {
		gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 1);
		gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 0);
		pr_debug("Discrete card powered down\n");
	}

	gmux_data->power_state = state;

	if (gmux_data->gpe >= 0 &&
	    !wait_for_completion_interruptible_timeout(&gmux_data->powerchange_done,
						       msecs_to_jiffies(200)))
		pr_warn("Timeout waiting for gmux switch to complete\n");

	return 0;
}

static int gmux_set_power_state(enum vga_switcheroo_client_id id,
				enum vga_switcheroo_state state)
{
	if (id == VGA_SWITCHEROO_IGD)
		return 0;

	return gmux_set_discrete_state(apple_gmux_data, state);
}

static int gmux_get_client_id(struct pci_dev *pdev)
{
	/*
	 * Early Macbook Pros with switchable graphics use nvidia
	 * integrated graphics. Hardcode that the 9400M is integrated.
	 */
	if (pdev->vendor == PCI_VENDOR_ID_INTEL)
		return VGA_SWITCHEROO_IGD;
	else if (pdev->vendor == PCI_VENDOR_ID_NVIDIA &&
		 pdev->device == 0x0863)
		return VGA_SWITCHEROO_IGD;
	else
		return VGA_SWITCHEROO_DIS;
}

static enum vga_switcheroo_client_id
gmux_active_client(struct apple_gmux_data *gmux_data)
{
	if (gmux_read8(gmux_data, GMUX_PORT_SWITCH_DISPLAY) == 2)
		return VGA_SWITCHEROO_IGD;

	return VGA_SWITCHEROO_DIS;
}

static struct vga_switcheroo_handler gmux_handler = {
	.switchto = gmux_switchto,
	.power_state = gmux_set_power_state,
	.get_client_id = gmux_get_client_id,
};

static inline void gmux_disable_interrupts(struct apple_gmux_data *gmux_data)
{
	gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_ENABLE,
		    GMUX_INTERRUPT_DISABLE);
}

static inline void gmux_enable_interrupts(struct apple_gmux_data *gmux_data)
{
	gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_ENABLE,
		    GMUX_INTERRUPT_ENABLE);
}

static inline u8 gmux_interrupt_get_status(struct apple_gmux_data *gmux_data)
{
	return gmux_read8(gmux_data, GMUX_PORT_INTERRUPT_STATUS);
}

static void gmux_clear_interrupts(struct apple_gmux_data *gmux_data)
{
	u8 status;

	/* to clear interrupts write back current status */
	status = gmux_interrupt_get_status(gmux_data);
	gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_STATUS, status);
}

static void gmux_notify_handler(acpi_handle device, u32 value, void *context)
{
	u8 status;
	struct pnp_dev *pnp = (struct pnp_dev *)context;
	struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);

	status = gmux_interrupt_get_status(gmux_data);
	gmux_disable_interrupts(gmux_data);
	pr_debug("Notify handler called: status %d\n", status);

	gmux_clear_interrupts(gmux_data);
	gmux_enable_interrupts(gmux_data);

	if (status & GMUX_INTERRUPT_STATUS_POWER)
		complete(&gmux_data->powerchange_done);
}

static int gmux_suspend(struct pnp_dev *pnp, pm_message_t state)
{
	struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
	gmux_data->resume_client_id = gmux_active_client(gmux_data);
	gmux_disable_interrupts(gmux_data);
	return 0;
}

static int gmux_resume(struct pnp_dev *pnp)
{
	struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
	gmux_enable_interrupts(gmux_data);
	gmux_switchto(gmux_data->resume_client_id);
	if (gmux_data->power_state == VGA_SWITCHEROO_OFF)
		gmux_set_discrete_state(gmux_data, gmux_data->power_state);
	return 0;
}

static int __devinit gmux_probe(struct pnp_dev *pnp,
				const struct pnp_device_id *id)
{
	struct apple_gmux_data *gmux_data;
	struct resource *res;
	struct backlight_properties props;
	struct backlight_device *bdev;
	u8 ver_major, ver_minor, ver_release;
	int ret = -ENXIO;
	acpi_status status;
	unsigned long long gpe;

	if (apple_gmux_data)
		return -EBUSY;

	gmux_data = kzalloc(sizeof(*gmux_data), GFP_KERNEL);
	if (!gmux_data)
		return -ENOMEM;
	pnp_set_drvdata(pnp, gmux_data);

	res = pnp_get_resource(pnp, IORESOURCE_IO, 0);
	if (!res) {
		pr_err("Failed to find gmux I/O resource\n");
		goto err_free;
	}

	gmux_data->iostart = res->start;
	gmux_data->iolen = res->end - res->start;

	if (gmux_data->iolen < GMUX_MIN_IO_LEN) {
		pr_err("gmux I/O region too small (%lu < %u)\n",
		       gmux_data->iolen, GMUX_MIN_IO_LEN);
		goto err_free;
	}

	if (!request_region(gmux_data->iostart, gmux_data->iolen,
			    "Apple gmux")) {
		pr_err("gmux I/O already in use\n");
		goto err_free;
	}

	/*
	 * Invalid version information may indicate either that the gmux
	 * device isn't present or that it's a new one that uses indexed
	 * io
	 */

	ver_major = gmux_read8(gmux_data, GMUX_PORT_VERSION_MAJOR);
	ver_minor = gmux_read8(gmux_data, GMUX_PORT_VERSION_MINOR);
	ver_release = gmux_read8(gmux_data, GMUX_PORT_VERSION_RELEASE);
	if (ver_major == 0xff && ver_minor == 0xff && ver_release == 0xff) {
		if (gmux_is_indexed(gmux_data)) {
			mutex_init(&gmux_data->index_lock);
			gmux_data->indexed = true;
		} else {
			pr_info("gmux device not present\n");
			ret = -ENODEV;
			goto err_release;
		}
		pr_info("Found indexed gmux\n");
	} else {
		pr_info("Found gmux version %d.%d.%d\n", ver_major, ver_minor,
			ver_release);
	}

	memset(&props, 0, sizeof(props));
	props.type = BACKLIGHT_PLATFORM;
	props.max_brightness = gmux_read32(gmux_data, GMUX_PORT_MAX_BRIGHTNESS);

	/*
	 * Currently it's assumed that the maximum brightness is less than
	 * 2^24 for compatibility with old gmux versions. Cap the max
	 * brightness at this value, but print a warning if the hardware
	 * reports something higher so that it can be fixed.
	 */
	if (WARN_ON(props.max_brightness > GMUX_MAX_BRIGHTNESS))
		props.max_brightness = GMUX_MAX_BRIGHTNESS;

	bdev = backlight_device_register("gmux_backlight", &pnp->dev,
					 gmux_data, &gmux_bl_ops, &props);
	if (IS_ERR(bdev)) {
		ret = PTR_ERR(bdev);
		goto err_release;
	}

	gmux_data->bdev = bdev;
	bdev->props.brightness = gmux_get_brightness(bdev);
	backlight_update_status(bdev);

	/*
	 * The backlight situation on Macs is complicated. If the gmux is
	 * present it's the best choice, because it always works for
	 * backlight control and supports more levels than other options.
	 * Disable the other backlight choices.
	 */
	acpi_video_dmi_promote_vendor();
#if defined (CONFIG_ACPI_VIDEO) || defined (CONFIG_ACPI_VIDEO_MODULE)
	acpi_video_unregister();
#endif
	apple_bl_unregister();

	gmux_data->power_state = VGA_SWITCHEROO_ON;

	gmux_data->dhandle = DEVICE_ACPI_HANDLE(&pnp->dev);
	if (!gmux_data->dhandle) {
		pr_err("Cannot find acpi handle for pnp device %s\n",
		       dev_name(&pnp->dev));
		ret = -ENODEV;
		goto err_notify;
	}

	status = acpi_evaluate_integer(gmux_data->dhandle, "GMGP", NULL, &gpe);
	if (ACPI_SUCCESS(status)) {
		gmux_data->gpe = (int)gpe;

		status = acpi_install_notify_handler(gmux_data->dhandle,
						     ACPI_DEVICE_NOTIFY,
						     &gmux_notify_handler, pnp);
		if (ACPI_FAILURE(status)) {
			pr_err("Install notify handler failed: %s\n",
			       acpi_format_exception(status));
			ret = -ENODEV;
			goto err_notify;
		}

		status = acpi_enable_gpe(NULL, gmux_data->gpe);
		if (ACPI_FAILURE(status)) {
			pr_err("Cannot enable gpe: %s\n",
			       acpi_format_exception(status));
			goto err_enable_gpe;
		}
	} else {
		pr_warn("No GPE found for gmux\n");
		gmux_data->gpe = -1;
	}

	if (vga_switcheroo_register_handler(&gmux_handler)) {
		ret = -ENODEV;
		goto err_register_handler;
	}

	init_completion(&gmux_data->powerchange_done);
	apple_gmux_data = gmux_data;
	gmux_enable_interrupts(gmux_data);

	return 0;

err_register_handler:
	if (gmux_data->gpe >= 0)
		acpi_disable_gpe(NULL, gmux_data->gpe);
err_enable_gpe:
	if (gmux_data->gpe >= 0)
		acpi_remove_notify_handler(gmux_data->dhandle,
					   ACPI_DEVICE_NOTIFY,
					   &gmux_notify_handler);
err_notify:
	backlight_device_unregister(bdev);
err_release:
	release_region(gmux_data->iostart, gmux_data->iolen);
err_free:
	kfree(gmux_data);
	return ret;
}

static void __devexit gmux_remove(struct pnp_dev *pnp)
{
	struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);

	vga_switcheroo_unregister_handler();
	gmux_disable_interrupts(gmux_data);
	if (gmux_data->gpe >= 0) {
		acpi_disable_gpe(NULL, gmux_data->gpe);
		acpi_remove_notify_handler(gmux_data->dhandle,
					   ACPI_DEVICE_NOTIFY,
					   &gmux_notify_handler);
	}

	backlight_device_unregister(gmux_data->bdev);

	release_region(gmux_data->iostart, gmux_data->iolen);
	apple_gmux_data = NULL;
	kfree(gmux_data);

	acpi_video_dmi_demote_vendor();
#if defined (CONFIG_ACPI_VIDEO) || defined (CONFIG_ACPI_VIDEO_MODULE)
	acpi_video_register();
#endif
	apple_bl_register();
}

static const struct pnp_device_id gmux_device_ids[] = {
	{"APP000B", 0},
	{"", 0}
};

static struct pnp_driver gmux_pnp_driver = {
	.name		= "apple-gmux",
	.probe		= gmux_probe,
	.remove		= __devexit_p(gmux_remove),
	.id_table	= gmux_device_ids,
	.suspend	= gmux_suspend,
	.resume		= gmux_resume
};

static int __init apple_gmux_init(void)
{
	return pnp_register_driver(&gmux_pnp_driver);
}

static void __exit apple_gmux_exit(void)
{
	pnp_unregister_driver(&gmux_pnp_driver);
}

module_init(apple_gmux_init);
module_exit(apple_gmux_exit);

MODULE_AUTHOR("Seth Forshee <seth.forshee@canonical.com>");
MODULE_DESCRIPTION("Apple Gmux Driver");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pnp, gmux_device_ids);
Commit	Line	Data
917ee75a SF	1	/*
	2	* Gmux driver for Apple laptops
	3	*
	4	* Copyright (C) Canonical Ltd. <seth.forshee@canonical.com>
76b487dd	5	* Copyright (C) 2010-2012 Andreas Heider <andreas@meetr.de>
917ee75a SF	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*/
	11
	12	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	13
	14	#include <linux/module.h>
	15	#include <linux/kernel.h>
	16	#include <linux/init.h>
	17	#include <linux/backlight.h>
	18	#include <linux/acpi.h>
	19	#include <linux/pnp.h>
	20	#include <linux/apple_bl.h>
	21	#include <linux/slab.h>
96ff7056	22	#include <linux/delay.h>
76b487dd AH	23	#include <linux/pci.h>
76b487dd AH	24	#include <linux/vga_switcheroo.h>
917ee75a SF	25	#include <acpi/video.h>
	26	#include <asm/io.h>
	27
	28	struct apple_gmux_data {
	29	unsigned long iostart;
	30	unsigned long iolen;
96ff7056 MG	31	bool indexed;
96ff7056 MG	32	struct mutex index_lock;
917ee75a SF	33
917ee75a SF	34	struct backlight_device *bdev;
76b487dd AH	35
	36	/* switcheroo data */
	37	acpi_handle dhandle;
	38	int gpe;
	39	enum vga_switcheroo_client_id resume_client_id;
	40	enum vga_switcheroo_state power_state;
	41	struct completion powerchange_done;
917ee75a SF	42	};
917ee75a SF	43
76b487dd AH	44	static struct apple_gmux_data *apple_gmux_data;
76b487dd AH	45
917ee75a SF	46	/*
	47	* gmux port offsets. Many of these are not yet used, but may be in the
	48	* future, and it's useful to have them documented here anyhow.
	49	*/
	50	#define GMUX_PORT_VERSION_MAJOR 0x04
	51	#define GMUX_PORT_VERSION_MINOR 0x05
	52	#define GMUX_PORT_VERSION_RELEASE 0x06
	53	#define GMUX_PORT_SWITCH_DISPLAY 0x10
	54	#define GMUX_PORT_SWITCH_GET_DISPLAY 0x11
	55	#define GMUX_PORT_INTERRUPT_ENABLE 0x14
	56	#define GMUX_PORT_INTERRUPT_STATUS 0x16
	57	#define GMUX_PORT_SWITCH_DDC 0x28
	58	#define GMUX_PORT_SWITCH_EXTERNAL 0x40
	59	#define GMUX_PORT_SWITCH_GET_EXTERNAL 0x41
	60	#define GMUX_PORT_DISCRETE_POWER 0x50
	61	#define GMUX_PORT_MAX_BRIGHTNESS 0x70
	62	#define GMUX_PORT_BRIGHTNESS 0x74
96ff7056 MG	63	#define GMUX_PORT_VALUE 0xc2
	64	#define GMUX_PORT_READ 0xd0
	65	#define GMUX_PORT_WRITE 0xd4
917ee75a SF	66
	67	#define GMUX_MIN_IO_LEN (GMUX_PORT_BRIGHTNESS + 4)
	68
	69	#define GMUX_INTERRUPT_ENABLE 0xff
	70	#define GMUX_INTERRUPT_DISABLE 0x00
	71
	72	#define GMUX_INTERRUPT_STATUS_ACTIVE 0
	73	#define GMUX_INTERRUPT_STATUS_DISPLAY (1 << 0)
	74	#define GMUX_INTERRUPT_STATUS_POWER (1 << 2)
	75	#define GMUX_INTERRUPT_STATUS_HOTPLUG (1 << 3)
	76
	77	#define GMUX_BRIGHTNESS_MASK 0x00ffffff
	78	#define GMUX_MAX_BRIGHTNESS GMUX_BRIGHTNESS_MASK
	79
96ff7056	80	static u8 gmux_pio_read8(struct apple_gmux_data *gmux_data, int port)
917ee75a SF	81	{
	82	return inb(gmux_data->iostart + port);
	83	}
	84
96ff7056	85	static void gmux_pio_write8(struct apple_gmux_data *gmux_data, int port,
917ee75a SF	86	u8 val)
	87	{
	88	outb(val, gmux_data->iostart + port);
	89	}
	90
96ff7056	91	static u32 gmux_pio_read32(struct apple_gmux_data *gmux_data, int port)
917ee75a SF	92	{
	93	return inl(gmux_data->iostart + port);
	94	}
	95
96ff7056 MG	96	static void gmux_pio_write32(struct apple_gmux_data *gmux_data, int port,
96ff7056 MG	97	u32 val)
7e30ed6b MG	98	{
	99	int i;
	100	u8 tmpval;
	101
	102	for (i = 0; i < 4; i++) {
	103	tmpval = (val >> (i * 8)) & 0xff;
	104	outb(tmpval, port + i);
	105	}
	106	}
	107
96ff7056 MG	108	static int gmux_index_wait_ready(struct apple_gmux_data *gmux_data)
	109	{
	110	int i = 200;
	111	u8 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
	112
	113	while (i && (gwr & 0x01)) {
	114	inb(gmux_data->iostart + GMUX_PORT_READ);
	115	gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
	116	udelay(100);
	117	i--;
	118	}
	119
	120	return !!i;
	121	}
	122
	123	static int gmux_index_wait_complete(struct apple_gmux_data *gmux_data)
	124	{
	125	int i = 200;
	126	u8 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
	127
	128	while (i && !(gwr & 0x01)) {
	129	gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
	130	udelay(100);
	131	i--;
	132	}
	133
	134	if (gwr & 0x01)
	135	inb(gmux_data->iostart + GMUX_PORT_READ);
	136
	137	return !!i;
	138	}
	139
	140	static u8 gmux_index_read8(struct apple_gmux_data *gmux_data, int port)
	141	{
	142	u8 val;
	143
	144	mutex_lock(&gmux_data->index_lock);
	145	outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ);
	146	gmux_index_wait_ready(gmux_data);
	147	val = inb(gmux_data->iostart + GMUX_PORT_VALUE);
	148	mutex_unlock(&gmux_data->index_lock);
	149
	150	return val;
	151	}
	152
	153	static void gmux_index_write8(struct apple_gmux_data *gmux_data, int port,
	154	u8 val)
	155	{
	156	mutex_lock(&gmux_data->index_lock);
	157	outb(val, gmux_data->iostart + GMUX_PORT_VALUE);
	158	gmux_index_wait_ready(gmux_data);
	159	outb(port & 0xff, gmux_data->iostart + GMUX_PORT_WRITE);
	160	gmux_index_wait_complete(gmux_data);
	161	mutex_unlock(&gmux_data->index_lock);
	162	}
	163
	164	static u32 gmux_index_read32(struct apple_gmux_data *gmux_data, int port)
	165	{
	166	u32 val;
	167
	168	mutex_lock(&gmux_data->index_lock);
	169	outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ);
	170	gmux_index_wait_ready(gmux_data);
	171	val = inl(gmux_data->iostart + GMUX_PORT_VALUE);
172	mutex_unlock(&gmux_data->index_lock);
173
174	return val;
175	}
176
177	static void gmux_index_write32(struct apple_gmux_data *gmux_data, int port,
178	u32 val)
179	{
180	int i;
181	u8 tmpval;
182
183	mutex_lock(&gmux_data->index_lock);
184
185	for (i = 0; i < 4; i++) {
186	tmpval = (val >> (i * 8)) & 0xff;
187	outb(tmpval, gmux_data->iostart + GMUX_PORT_VALUE + i);
188	}
189
190	gmux_index_wait_ready(gmux_data);
191	outb(port & 0xff, gmux_data->iostart + GMUX_PORT_WRITE);
192	gmux_index_wait_complete(gmux_data);
193	mutex_unlock(&gmux_data->index_lock);
194	}
195
196	static u8 gmux_read8(struct apple_gmux_data *gmux_data, int port)
197	{
198	if (gmux_data->indexed)
199	return gmux_index_read8(gmux_data, port);
200	else
201	return gmux_pio_read8(gmux_data, port);
202	}
203
204	static void gmux_write8(struct apple_gmux_data *gmux_data, int port, u8 val)
205	{
206	if (gmux_data->indexed)
207	gmux_index_write8(gmux_data, port, val);
208	else
209	gmux_pio_write8(gmux_data, port, val);
210	}
211
212	static u32 gmux_read32(struct apple_gmux_data *gmux_data, int port)
213	{
214	if (gmux_data->indexed)
215	return gmux_index_read32(gmux_data, port);
216	else
217	return gmux_pio_read32(gmux_data, port);
218	}
219
220	static void gmux_write32(struct apple_gmux_data *gmux_data, int port,
221	u32 val)
222	{
223	if (gmux_data->indexed)
224	gmux_index_write32(gmux_data, port, val);
225	else
226	gmux_pio_write32(gmux_data, port, val);
227	}
228
229	static bool gmux_is_indexed(struct apple_gmux_data *gmux_data)
230	{
231	u16 val;
232
233	outb(0xaa, gmux_data->iostart + 0xcc);
234	outb(0x55, gmux_data->iostart + 0xcd);
235	outb(0x00, gmux_data->iostart + 0xce);
236
237	val = inb(gmux_data->iostart + 0xcc) \|
238	(inb(gmux_data->iostart + 0xcd) << 8);
239
240	if (val == 0x55aa)
241	return true;
242
243	return false;
244	}
245
917ee75a SF	246	static int gmux_get_brightness(struct backlight_device *bd)
	247	{
	248	struct apple_gmux_data *gmux_data = bl_get_data(bd);
	249	return gmux_read32(gmux_data, GMUX_PORT_BRIGHTNESS) &
	250	GMUX_BRIGHTNESS_MASK;
	251	}
	252
	253	static int gmux_update_status(struct backlight_device *bd)
	254	{
	255	struct apple_gmux_data *gmux_data = bl_get_data(bd);
	256	u32 brightness = bd->props.brightness;
	257
96960880	258	if (bd->props.state & BL_CORE_SUSPENDED)
a2f01a89	259	return 0;
96960880	260
7e30ed6b	261	gmux_write32(gmux_data, GMUX_PORT_BRIGHTNESS, brightness);
917ee75a SF	262
	263	return 0;
	264	}
	265
	266	static const struct backlight_ops gmux_bl_ops = {
96960880	267	.options = BL_CORE_SUSPENDRESUME,
917ee75a SF	268	.get_brightness = gmux_get_brightness,
	269	.update_status = gmux_update_status,
	270	};
	271
76b487dd AH	272	static int gmux_switchto(enum vga_switcheroo_client_id id)
	273	{
	274	if (id == VGA_SWITCHEROO_IGD) {
	275	gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DDC, 1);
	276	gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DISPLAY, 2);
	277	gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_EXTERNAL, 2);
	278	} else {
	279	gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DDC, 2);
	280	gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DISPLAY, 3);
	281	gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_EXTERNAL, 3);
	282	}
	283
	284	return 0;
	285	}
	286
	287	static int gmux_set_discrete_state(struct apple_gmux_data *gmux_data,
	288	enum vga_switcheroo_state state)
	289	{
	290	INIT_COMPLETION(gmux_data->powerchange_done);
	291
	292	if (state == VGA_SWITCHEROO_ON) {
	293	gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 1);
	294	gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 3);
	295	pr_debug("Discrete card powered up\n");
	296	} else {
	297	gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 1);
	298	gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 0);
	299	pr_debug("Discrete card powered down\n");
	300	}
	301
	302	gmux_data->power_state = state;
	303
	304	if (gmux_data->gpe >= 0 &&
	305	!wait_for_completion_interruptible_timeout(&gmux_data->powerchange_done,
	306	msecs_to_jiffies(200)))
	307	pr_warn("Timeout waiting for gmux switch to complete\n");
	308
	309	return 0;
	310	}
	311
	312	static int gmux_set_power_state(enum vga_switcheroo_client_id id,
	313	enum vga_switcheroo_state state)
	314	{
	315	if (id == VGA_SWITCHEROO_IGD)
	316	return 0;
	317
	318	return gmux_set_discrete_state(apple_gmux_data, state);
	319	}
	320
	321	static int gmux_get_client_id(struct pci_dev *pdev)
	322	{
	323	/*
	324	* Early Macbook Pros with switchable graphics use nvidia
	325	* integrated graphics. Hardcode that the 9400M is integrated.
	326	*/
	327	if (pdev->vendor == PCI_VENDOR_ID_INTEL)
	328	return VGA_SWITCHEROO_IGD;
	329	else if (pdev->vendor == PCI_VENDOR_ID_NVIDIA &&
	330	pdev->device == 0x0863)
	331	return VGA_SWITCHEROO_IGD;
	332	else
	333	return VGA_SWITCHEROO_DIS;
	334	}
	335
336	static enum vga_switcheroo_client_id
337	gmux_active_client(struct apple_gmux_data *gmux_data)
338	{
339	if (gmux_read8(gmux_data, GMUX_PORT_SWITCH_DISPLAY) == 2)
340	return VGA_SWITCHEROO_IGD;
341
342	return VGA_SWITCHEROO_DIS;
343	}
344
345	static struct vga_switcheroo_handler gmux_handler = {
346	.switchto = gmux_switchto,
347	.power_state = gmux_set_power_state,
348	.get_client_id = gmux_get_client_id,
349	};
350
351	static inline void gmux_disable_interrupts(struct apple_gmux_data *gmux_data)
352	{
353	gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_ENABLE,
354	GMUX_INTERRUPT_DISABLE);
355	}
356
357	static inline void gmux_enable_interrupts(struct apple_gmux_data *gmux_data)
358	{
359	gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_ENABLE,
360	GMUX_INTERRUPT_ENABLE);
361	}
362
363	static inline u8 gmux_interrupt_get_status(struct apple_gmux_data *gmux_data)
364	{
365	return gmux_read8(gmux_data, GMUX_PORT_INTERRUPT_STATUS);
366	}
367
368	static void gmux_clear_interrupts(struct apple_gmux_data *gmux_data)
369	{
370	u8 status;
371
372	/* to clear interrupts write back current status */
373	status = gmux_interrupt_get_status(gmux_data);
374	gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_STATUS, status);
375	}
376
377	static void gmux_notify_handler(acpi_handle device, u32 value, void *context)
378	{
379	u8 status;
380	struct pnp_dev pnp = (struct pnp_dev )context;
381	struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
382
383	status = gmux_interrupt_get_status(gmux_data);
384	gmux_disable_interrupts(gmux_data);
385	pr_debug("Notify handler called: status %d\n", status);
386
387	gmux_clear_interrupts(gmux_data);
388	gmux_enable_interrupts(gmux_data);
389
390	if (status & GMUX_INTERRUPT_STATUS_POWER)
391	complete(&gmux_data->powerchange_done);
392	}
393
394	static int gmux_suspend(struct pnp_dev *pnp, pm_message_t state)
395	{
396	struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
397	gmux_data->resume_client_id = gmux_active_client(gmux_data);
398	gmux_disable_interrupts(gmux_data);
399	return 0;
400	}
401
402	static int gmux_resume(struct pnp_dev *pnp)
403	{
404	struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
405	gmux_enable_interrupts(gmux_data);
406	gmux_switchto(gmux_data->resume_client_id);
407	if (gmux_data->power_state == VGA_SWITCHEROO_OFF)
408	gmux_set_discrete_state(gmux_data, gmux_data->power_state);
409	return 0;
410	}
411
917ee75a SF	412	static int __devinit gmux_probe(struct pnp_dev *pnp,
	413	const struct pnp_device_id *id)
	414	{
	415	struct apple_gmux_data *gmux_data;
	416	struct resource *res;
	417	struct backlight_properties props;
	418	struct backlight_device *bdev;
	419	u8 ver_major, ver_minor, ver_release;
	420	int ret = -ENXIO;
76b487dd AH	421	acpi_status status;
	422	unsigned long long gpe;
	423
	424	if (apple_gmux_data)
	425	return -EBUSY;
917ee75a SF	426
	427	gmux_data = kzalloc(sizeof(*gmux_data), GFP_KERNEL);
	428	if (!gmux_data)
	429	return -ENOMEM;
	430	pnp_set_drvdata(pnp, gmux_data);
	431
	432	res = pnp_get_resource(pnp, IORESOURCE_IO, 0);
	433	if (!res) {
	434	pr_err("Failed to find gmux I/O resource\n");
	435	goto err_free;
	436	}
	437
	438	gmux_data->iostart = res->start;
	439	gmux_data->iolen = res->end - res->start;
	440
	441	if (gmux_data->iolen < GMUX_MIN_IO_LEN) {
	442	pr_err("gmux I/O region too small (%lu < %u)\n",
	443	gmux_data->iolen, GMUX_MIN_IO_LEN);
	444	goto err_free;
	445	}
	446
	447	if (!request_region(gmux_data->iostart, gmux_data->iolen,
	448	"Apple gmux")) {
	449	pr_err("gmux I/O already in use\n");
	450	goto err_free;
	451	}
	452
	453	/*
96ff7056 MG	454	* Invalid version information may indicate either that the gmux
	455	* device isn't present or that it's a new one that uses indexed
	456	* io
917ee75a	457	*/
96ff7056	458
917ee75a SF	459	ver_major = gmux_read8(gmux_data, GMUX_PORT_VERSION_MAJOR);
	460	ver_minor = gmux_read8(gmux_data, GMUX_PORT_VERSION_MINOR);
	461	ver_release = gmux_read8(gmux_data, GMUX_PORT_VERSION_RELEASE);
	462	if (ver_major == 0xff && ver_minor == 0xff && ver_release == 0xff) {
96ff7056 MG	463	if (gmux_is_indexed(gmux_data)) {
	464	mutex_init(&gmux_data->index_lock);
	465	gmux_data->indexed = true;
	466	} else {
	467	pr_info("gmux device not present\n");
	468	ret = -ENODEV;
	469	goto err_release;
	470	}
	471	pr_info("Found indexed gmux\n");
	472	} else {
	473	pr_info("Found gmux version %d.%d.%d\n", ver_major, ver_minor,
	474	ver_release);
917ee75a SF	475	}
917ee75a SF	476
917ee75a SF	477	memset(&props, 0, sizeof(props));
	478	props.type = BACKLIGHT_PLATFORM;
	479	props.max_brightness = gmux_read32(gmux_data, GMUX_PORT_MAX_BRIGHTNESS);
	480
	481	/*
	482	* Currently it's assumed that the maximum brightness is less than
	483	* 2^24 for compatibility with old gmux versions. Cap the max
	484	* brightness at this value, but print a warning if the hardware
	485	* reports something higher so that it can be fixed.
	486	*/
	487	if (WARN_ON(props.max_brightness > GMUX_MAX_BRIGHTNESS))
	488	props.max_brightness = GMUX_MAX_BRIGHTNESS;
	489
	490	bdev = backlight_device_register("gmux_backlight", &pnp->dev,
	491	gmux_data, &gmux_bl_ops, &props);
	492	if (IS_ERR(bdev)) {
	493	ret = PTR_ERR(bdev);
	494	goto err_release;
	495	}
	496
	497	gmux_data->bdev = bdev;
	498	bdev->props.brightness = gmux_get_brightness(bdev);
	499	backlight_update_status(bdev);
	500
	501	/*
	502	* The backlight situation on Macs is complicated. If the gmux is
	503	* present it's the best choice, because it always works for
	504	* backlight control and supports more levels than other options.
	505	* Disable the other backlight choices.
	506	*/
a60b2176	507	acpi_video_dmi_promote_vendor();
9f6f955a	508	#if defined (CONFIG_ACPI_VIDEO) \|\| defined (CONFIG_ACPI_VIDEO_MODULE)
917ee75a	509	acpi_video_unregister();
a60b2176	510	#endif
917ee75a SF	511	apple_bl_unregister();
917ee75a SF	512
76b487dd AH	513	gmux_data->power_state = VGA_SWITCHEROO_ON;
	514
	515	gmux_data->dhandle = DEVICE_ACPI_HANDLE(&pnp->dev);
	516	if (!gmux_data->dhandle) {
	517	pr_err("Cannot find acpi handle for pnp device %s\n",
	518	dev_name(&pnp->dev));
	519	ret = -ENODEV;
	520	goto err_notify;
	521	}
	522
	523	status = acpi_evaluate_integer(gmux_data->dhandle, "GMGP", NULL, &gpe);
	524	if (ACPI_SUCCESS(status)) {
	525	gmux_data->gpe = (int)gpe;
	526
	527	status = acpi_install_notify_handler(gmux_data->dhandle,
	528	ACPI_DEVICE_NOTIFY,
	529	&gmux_notify_handler, pnp);
	530	if (ACPI_FAILURE(status)) {
	531	pr_err("Install notify handler failed: %s\n",
	532	acpi_format_exception(status));
	533	ret = -ENODEV;
	534	goto err_notify;
	535	}
	536
	537	status = acpi_enable_gpe(NULL, gmux_data->gpe);
	538	if (ACPI_FAILURE(status)) {
	539	pr_err("Cannot enable gpe: %s\n",
	540	acpi_format_exception(status));
	541	goto err_enable_gpe;
	542	}
	543	} else {
	544	pr_warn("No GPE found for gmux\n");
	545	gmux_data->gpe = -1;
	546	}
	547
	548	if (vga_switcheroo_register_handler(&gmux_handler)) {
	549	ret = -ENODEV;
	550	goto err_register_handler;
	551	}
	552
	553	init_completion(&gmux_data->powerchange_done);
	554	apple_gmux_data = gmux_data;
	555	gmux_enable_interrupts(gmux_data);
	556
917ee75a SF	557	return 0;
917ee75a SF	558
76b487dd AH	559	err_register_handler:
	560	if (gmux_data->gpe >= 0)
	561	acpi_disable_gpe(NULL, gmux_data->gpe);
	562	err_enable_gpe:
	563	if (gmux_data->gpe >= 0)
	564	acpi_remove_notify_handler(gmux_data->dhandle,
	565	ACPI_DEVICE_NOTIFY,
	566	&gmux_notify_handler);
	567	err_notify:
	568	backlight_device_unregister(bdev);
917ee75a SF	569	err_release:
	570	release_region(gmux_data->iostart, gmux_data->iolen);
	571	err_free:
	572	kfree(gmux_data);
	573	return ret;
	574	}
	575
	576	static void __devexit gmux_remove(struct pnp_dev *pnp)
	577	{
	578	struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
	579
76b487dd AH	580	vga_switcheroo_unregister_handler();
	581	gmux_disable_interrupts(gmux_data);
	582	if (gmux_data->gpe >= 0) {
	583	acpi_disable_gpe(NULL, gmux_data->gpe);
	584	acpi_remove_notify_handler(gmux_data->dhandle,
	585	ACPI_DEVICE_NOTIFY,
	586	&gmux_notify_handler);
	587	}
	588
917ee75a	589	backlight_device_unregister(gmux_data->bdev);
76b487dd	590
917ee75a	591	release_region(gmux_data->iostart, gmux_data->iolen);
76b487dd	592	apple_gmux_data = NULL;
917ee75a SF	593	kfree(gmux_data);
917ee75a SF	594
a60b2176	595	acpi_video_dmi_demote_vendor();
9f6f955a	596	#if defined (CONFIG_ACPI_VIDEO) \|\| defined (CONFIG_ACPI_VIDEO_MODULE)
917ee75a	597	acpi_video_register();
a60b2176	598	#endif
917ee75a SF	599	apple_bl_register();
	600	}
	601
	602	static const struct pnp_device_id gmux_device_ids[] = {
	603	{"APP000B", 0},
	604	{"", 0}
	605	};
	606
	607	static struct pnp_driver gmux_pnp_driver = {
	608	.name = "apple-gmux",
	609	.probe = gmux_probe,
	610	.remove = __devexit_p(gmux_remove),
	611	.id_table = gmux_device_ids,
76b487dd AH	612	.suspend = gmux_suspend,
76b487dd AH	613	.resume = gmux_resume
917ee75a SF	614	};
	615
	616	static int __init apple_gmux_init(void)
	617	{
	618	return pnp_register_driver(&gmux_pnp_driver);
	619	}
	620
	621	static void __exit apple_gmux_exit(void)
	622	{
	623	pnp_unregister_driver(&gmux_pnp_driver);
	624	}
	625
	626	module_init(apple_gmux_init);
	627	module_exit(apple_gmux_exit);
	628
	629	MODULE_AUTHOR("Seth Forshee <seth.forshee@canonical.com>");
	630	MODULE_DESCRIPTION("Apple Gmux Driver");
	631	MODULE_LICENSE("GPL");
	632	MODULE_DEVICE_TABLE(pnp, gmux_device_ids);