[GitHub/mt8127/android_kernel_alcatel_ttab.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, gmux_data->iostart + 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);
	gmux_index_wait_ready(gmux_data);
	outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ);
	gmux_index_wait_complete(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);
	gmux_index_wait_ready(gmux_data);
	outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ);
	gmux_index_wait_complete(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 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)) {
			u32 version;
			mutex_init(&gmux_data->index_lock);
			gmux_data->indexed = true;
			version = gmux_read32(gmux_data,
				GMUX_PORT_VERSION_MAJOR);
			ver_major = (version >> 24) & 0xff;
			ver_minor = (version >> 16) & 0xff;
			ver_release = (version >> 8) & 0xff;
		} else {
			pr_info("gmux device not present\n");
			ret = -ENODEV;
			goto err_release;
		}
	}
	pr_info("Found gmux version %d.%d.%d [%s]\n", ver_major, ver_minor,
		ver_release, (gmux_data->indexed ? "indexed" : "classic"));

	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();
	acpi_video_unregister();
	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 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();
	acpi_video_register();
	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		= 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;
e6d9d3d5	104	outb(tmpval, gmux_data->iostart + port + i);
7e30ed6b MG	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);
96ff7056	145	gmux_index_wait_ready(gmux_data);
c5a50529 BF	146	outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ);
c5a50529 BF	147	gmux_index_wait_complete(gmux_data);
96ff7056 MG	148	val = inb(gmux_data->iostart + GMUX_PORT_VALUE);
	149	mutex_unlock(&gmux_data->index_lock);
	150
	151	return val;
	152	}
	153
	154	static void gmux_index_write8(struct apple_gmux_data *gmux_data, int port,
	155	u8 val)
	156	{
	157	mutex_lock(&gmux_data->index_lock);
	158	outb(val, gmux_data->iostart + GMUX_PORT_VALUE);
	159	gmux_index_wait_ready(gmux_data);
	160	outb(port & 0xff, gmux_data->iostart + GMUX_PORT_WRITE);
	161	gmux_index_wait_complete(gmux_data);
	162	mutex_unlock(&gmux_data->index_lock);
	163	}
	164
	165	static u32 gmux_index_read32(struct apple_gmux_data *gmux_data, int port)
	166	{
	167	u32 val;
	168
	169	mutex_lock(&gmux_data->index_lock);
96ff7056	170	gmux_index_wait_ready(gmux_data);
c5a50529 BF	171	outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ);
c5a50529 BF	172	gmux_index_wait_complete(gmux_data);
96ff7056 MG	173	val = inl(gmux_data->iostart + GMUX_PORT_VALUE);
	174	mutex_unlock(&gmux_data->index_lock);
	175
	176	return val;
	177	}
	178
	179	static void gmux_index_write32(struct apple_gmux_data *gmux_data, int port,
	180	u32 val)
	181	{
	182	int i;
	183	u8 tmpval;
	184
	185	mutex_lock(&gmux_data->index_lock);
	186
	187	for (i = 0; i < 4; i++) {
	188	tmpval = (val >> (i * 8)) & 0xff;
	189	outb(tmpval, gmux_data->iostart + GMUX_PORT_VALUE + i);
	190	}
	191
	192	gmux_index_wait_ready(gmux_data);
	193	outb(port & 0xff, gmux_data->iostart + GMUX_PORT_WRITE);
	194	gmux_index_wait_complete(gmux_data);
	195	mutex_unlock(&gmux_data->index_lock);
	196	}
	197
	198	static u8 gmux_read8(struct apple_gmux_data *gmux_data, int port)
	199	{
	200	if (gmux_data->indexed)
	201	return gmux_index_read8(gmux_data, port);
	202	else
	203	return gmux_pio_read8(gmux_data, port);
	204	}
	205
	206	static void gmux_write8(struct apple_gmux_data *gmux_data, int port, u8 val)
	207	{
	208	if (gmux_data->indexed)
	209	gmux_index_write8(gmux_data, port, val);
	210	else
	211	gmux_pio_write8(gmux_data, port, val);
	212	}
	213
	214	static u32 gmux_read32(struct apple_gmux_data *gmux_data, int port)
	215	{
	216	if (gmux_data->indexed)
	217	return gmux_index_read32(gmux_data, port);
	218	else
	219	return gmux_pio_read32(gmux_data, port);
	220	}
	221
	222	static void gmux_write32(struct apple_gmux_data *gmux_data, int port,
	223	u32 val)
	224	{
	225	if (gmux_data->indexed)
	226	gmux_index_write32(gmux_data, port, val);
	227	else
	228	gmux_pio_write32(gmux_data, port, val);
	229	}
	230
	231	static bool gmux_is_indexed(struct apple_gmux_data *gmux_data)
	232	{
	233	u16 val;
	234
	235	outb(0xaa, gmux_data->iostart + 0xcc);
	236	outb(0x55, gmux_data->iostart + 0xcd);
237	outb(0x00, gmux_data->iostart + 0xce);
238
239	val = inb(gmux_data->iostart + 0xcc) \|
240	(inb(gmux_data->iostart + 0xcd) << 8);
241
242	if (val == 0x55aa)
243	return true;
244
245	return false;
246	}
247
917ee75a SF	248	static int gmux_get_brightness(struct backlight_device *bd)
	249	{
	250	struct apple_gmux_data *gmux_data = bl_get_data(bd);
	251	return gmux_read32(gmux_data, GMUX_PORT_BRIGHTNESS) &
	252	GMUX_BRIGHTNESS_MASK;
	253	}
	254
	255	static int gmux_update_status(struct backlight_device *bd)
	256	{
	257	struct apple_gmux_data *gmux_data = bl_get_data(bd);
	258	u32 brightness = bd->props.brightness;
	259
96960880	260	if (bd->props.state & BL_CORE_SUSPENDED)
a2f01a89	261	return 0;
96960880	262
7e30ed6b	263	gmux_write32(gmux_data, GMUX_PORT_BRIGHTNESS, brightness);
917ee75a SF	264
	265	return 0;
	266	}
	267
	268	static const struct backlight_ops gmux_bl_ops = {
96960880	269	.options = BL_CORE_SUSPENDRESUME,
917ee75a SF	270	.get_brightness = gmux_get_brightness,
	271	.update_status = gmux_update_status,
	272	};
	273
76b487dd AH	274	static int gmux_switchto(enum vga_switcheroo_client_id id)
	275	{
	276	if (id == VGA_SWITCHEROO_IGD) {
	277	gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DDC, 1);
	278	gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DISPLAY, 2);
	279	gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_EXTERNAL, 2);
	280	} else {
	281	gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DDC, 2);
	282	gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DISPLAY, 3);
	283	gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_EXTERNAL, 3);
	284	}
	285
	286	return 0;
	287	}
	288
	289	static int gmux_set_discrete_state(struct apple_gmux_data *gmux_data,
	290	enum vga_switcheroo_state state)
	291	{
	292	INIT_COMPLETION(gmux_data->powerchange_done);
	293
	294	if (state == VGA_SWITCHEROO_ON) {
	295	gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 1);
	296	gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 3);
	297	pr_debug("Discrete card powered up\n");
	298	} else {
	299	gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 1);
	300	gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 0);
	301	pr_debug("Discrete card powered down\n");
	302	}
	303
	304	gmux_data->power_state = state;
	305
	306	if (gmux_data->gpe >= 0 &&
	307	!wait_for_completion_interruptible_timeout(&gmux_data->powerchange_done,
	308	msecs_to_jiffies(200)))
	309	pr_warn("Timeout waiting for gmux switch to complete\n");
	310
	311	return 0;
	312	}
	313
	314	static int gmux_set_power_state(enum vga_switcheroo_client_id id,
	315	enum vga_switcheroo_state state)
	316	{
	317	if (id == VGA_SWITCHEROO_IGD)
	318	return 0;
	319
	320	return gmux_set_discrete_state(apple_gmux_data, state);
	321	}
	322
	323	static int gmux_get_client_id(struct pci_dev *pdev)
	324	{
	325	/*
	326	* Early Macbook Pros with switchable graphics use nvidia
	327	* integrated graphics. Hardcode that the 9400M is integrated.
	328	*/
	329	if (pdev->vendor == PCI_VENDOR_ID_INTEL)
	330	return VGA_SWITCHEROO_IGD;
	331	else if (pdev->vendor == PCI_VENDOR_ID_NVIDIA &&
	332	pdev->device == 0x0863)
	333	return VGA_SWITCHEROO_IGD;
	334	else
	335	return VGA_SWITCHEROO_DIS;
	336	}
	337
338	static enum vga_switcheroo_client_id
339	gmux_active_client(struct apple_gmux_data *gmux_data)
340	{
341	if (gmux_read8(gmux_data, GMUX_PORT_SWITCH_DISPLAY) == 2)
342	return VGA_SWITCHEROO_IGD;
343
344	return VGA_SWITCHEROO_DIS;
345	}
346
347	static struct vga_switcheroo_handler gmux_handler = {
348	.switchto = gmux_switchto,
349	.power_state = gmux_set_power_state,
350	.get_client_id = gmux_get_client_id,
351	};
352
353	static inline void gmux_disable_interrupts(struct apple_gmux_data *gmux_data)
354	{
355	gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_ENABLE,
356	GMUX_INTERRUPT_DISABLE);
357	}
358
359	static inline void gmux_enable_interrupts(struct apple_gmux_data *gmux_data)
360	{
361	gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_ENABLE,
362	GMUX_INTERRUPT_ENABLE);
363	}
364
365	static inline u8 gmux_interrupt_get_status(struct apple_gmux_data *gmux_data)
366	{
367	return gmux_read8(gmux_data, GMUX_PORT_INTERRUPT_STATUS);
368	}
369
370	static void gmux_clear_interrupts(struct apple_gmux_data *gmux_data)
371	{
372	u8 status;
373
374	/* to clear interrupts write back current status */
375	status = gmux_interrupt_get_status(gmux_data);
376	gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_STATUS, status);
377	}
378
379	static void gmux_notify_handler(acpi_handle device, u32 value, void *context)
380	{
381	u8 status;
382	struct pnp_dev pnp = (struct pnp_dev )context;
383	struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
384
385	status = gmux_interrupt_get_status(gmux_data);
386	gmux_disable_interrupts(gmux_data);
387	pr_debug("Notify handler called: status %d\n", status);
388
389	gmux_clear_interrupts(gmux_data);
390	gmux_enable_interrupts(gmux_data);
391
392	if (status & GMUX_INTERRUPT_STATUS_POWER)
393	complete(&gmux_data->powerchange_done);
394	}
395
396	static int gmux_suspend(struct pnp_dev *pnp, pm_message_t state)
397	{
398	struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
399	gmux_data->resume_client_id = gmux_active_client(gmux_data);
400	gmux_disable_interrupts(gmux_data);
401	return 0;
402	}
403
404	static int gmux_resume(struct pnp_dev *pnp)
405	{
406	struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
407	gmux_enable_interrupts(gmux_data);
408	gmux_switchto(gmux_data->resume_client_id);
409	if (gmux_data->power_state == VGA_SWITCHEROO_OFF)
410	gmux_set_discrete_state(gmux_data, gmux_data->power_state);
411	return 0;
412	}
413
b859f159	414	static int gmux_probe(struct pnp_dev pnp, const struct pnp_device_id id)
917ee75a SF	415	{
	416	struct apple_gmux_data *gmux_data;
	417	struct resource *res;
	418	struct backlight_properties props;
	419	struct backlight_device *bdev;
	420	u8 ver_major, ver_minor, ver_release;
	421	int ret = -ENXIO;
76b487dd AH	422	acpi_status status;
	423	unsigned long long gpe;
	424
	425	if (apple_gmux_data)
	426	return -EBUSY;
917ee75a SF	427
	428	gmux_data = kzalloc(sizeof(*gmux_data), GFP_KERNEL);
	429	if (!gmux_data)
	430	return -ENOMEM;
	431	pnp_set_drvdata(pnp, gmux_data);
	432
	433	res = pnp_get_resource(pnp, IORESOURCE_IO, 0);
	434	if (!res) {
	435	pr_err("Failed to find gmux I/O resource\n");
	436	goto err_free;
	437	}
	438
	439	gmux_data->iostart = res->start;
	440	gmux_data->iolen = res->end - res->start;
	441
	442	if (gmux_data->iolen < GMUX_MIN_IO_LEN) {
	443	pr_err("gmux I/O region too small (%lu < %u)\n",
	444	gmux_data->iolen, GMUX_MIN_IO_LEN);
	445	goto err_free;
	446	}
	447
	448	if (!request_region(gmux_data->iostart, gmux_data->iolen,
	449	"Apple gmux")) {
	450	pr_err("gmux I/O already in use\n");
	451	goto err_free;
	452	}
	453
	454	/*
96ff7056 MG	455	* Invalid version information may indicate either that the gmux
	456	* device isn't present or that it's a new one that uses indexed
	457	* io
917ee75a	458	*/
96ff7056	459
917ee75a SF	460	ver_major = gmux_read8(gmux_data, GMUX_PORT_VERSION_MAJOR);
	461	ver_minor = gmux_read8(gmux_data, GMUX_PORT_VERSION_MINOR);
	462	ver_release = gmux_read8(gmux_data, GMUX_PORT_VERSION_RELEASE);
	463	if (ver_major == 0xff && ver_minor == 0xff && ver_release == 0xff) {
96ff7056	464	if (gmux_is_indexed(gmux_data)) {
07f377da	465	u32 version;
96ff7056 MG	466	mutex_init(&gmux_data->index_lock);
96ff7056 MG	467	gmux_data->indexed = true;
07f377da BF	468	version = gmux_read32(gmux_data,
	469	GMUX_PORT_VERSION_MAJOR);
	470	ver_major = (version >> 24) & 0xff;
	471	ver_minor = (version >> 16) & 0xff;
	472	ver_release = (version >> 8) & 0xff;
96ff7056 MG	473	} else {
	474	pr_info("gmux device not present\n");
	475	ret = -ENODEV;
	476	goto err_release;
	477	}
917ee75a	478	}
07f377da BF	479	pr_info("Found gmux version %d.%d.%d [%s]\n", ver_major, ver_minor,
07f377da BF	480	ver_release, (gmux_data->indexed ? "indexed" : "classic"));
917ee75a	481
917ee75a SF	482	memset(&props, 0, sizeof(props));
	483	props.type = BACKLIGHT_PLATFORM;
	484	props.max_brightness = gmux_read32(gmux_data, GMUX_PORT_MAX_BRIGHTNESS);
	485
	486	/*
	487	* Currently it's assumed that the maximum brightness is less than
	488	* 2^24 for compatibility with old gmux versions. Cap the max
	489	* brightness at this value, but print a warning if the hardware
	490	* reports something higher so that it can be fixed.
	491	*/
	492	if (WARN_ON(props.max_brightness > GMUX_MAX_BRIGHTNESS))
	493	props.max_brightness = GMUX_MAX_BRIGHTNESS;
	494
	495	bdev = backlight_device_register("gmux_backlight", &pnp->dev,
	496	gmux_data, &gmux_bl_ops, &props);
	497	if (IS_ERR(bdev)) {
	498	ret = PTR_ERR(bdev);
	499	goto err_release;
	500	}
	501
	502	gmux_data->bdev = bdev;
	503	bdev->props.brightness = gmux_get_brightness(bdev);
	504	backlight_update_status(bdev);
	505
	506	/*
	507	* The backlight situation on Macs is complicated. If the gmux is
	508	* present it's the best choice, because it always works for
	509	* backlight control and supports more levels than other options.
	510	* Disable the other backlight choices.
	511	*/
a60b2176	512	acpi_video_dmi_promote_vendor();
917ee75a SF	513	acpi_video_unregister();
	514	apple_bl_unregister();
	515
76b487dd AH	516	gmux_data->power_state = VGA_SWITCHEROO_ON;
	517
	518	gmux_data->dhandle = DEVICE_ACPI_HANDLE(&pnp->dev);
	519	if (!gmux_data->dhandle) {
	520	pr_err("Cannot find acpi handle for pnp device %s\n",
	521	dev_name(&pnp->dev));
	522	ret = -ENODEV;
	523	goto err_notify;
	524	}
	525
	526	status = acpi_evaluate_integer(gmux_data->dhandle, "GMGP", NULL, &gpe);
	527	if (ACPI_SUCCESS(status)) {
	528	gmux_data->gpe = (int)gpe;
	529
	530	status = acpi_install_notify_handler(gmux_data->dhandle,
	531	ACPI_DEVICE_NOTIFY,
	532	&gmux_notify_handler, pnp);
	533	if (ACPI_FAILURE(status)) {
	534	pr_err("Install notify handler failed: %s\n",
	535	acpi_format_exception(status));
	536	ret = -ENODEV;
	537	goto err_notify;
	538	}
	539
	540	status = acpi_enable_gpe(NULL, gmux_data->gpe);
	541	if (ACPI_FAILURE(status)) {
	542	pr_err("Cannot enable gpe: %s\n",
	543	acpi_format_exception(status));
	544	goto err_enable_gpe;
	545	}
	546	} else {
	547	pr_warn("No GPE found for gmux\n");
	548	gmux_data->gpe = -1;
	549	}
	550
	551	if (vga_switcheroo_register_handler(&gmux_handler)) {
	552	ret = -ENODEV;
	553	goto err_register_handler;
	554	}
	555
	556	init_completion(&gmux_data->powerchange_done);
	557	apple_gmux_data = gmux_data;
	558	gmux_enable_interrupts(gmux_data);
	559
917ee75a SF	560	return 0;
917ee75a SF	561
76b487dd AH	562	err_register_handler:
	563	if (gmux_data->gpe >= 0)
	564	acpi_disable_gpe(NULL, gmux_data->gpe);
	565	err_enable_gpe:
	566	if (gmux_data->gpe >= 0)
	567	acpi_remove_notify_handler(gmux_data->dhandle,
	568	ACPI_DEVICE_NOTIFY,
	569	&gmux_notify_handler);
	570	err_notify:
	571	backlight_device_unregister(bdev);
917ee75a SF	572	err_release:
	573	release_region(gmux_data->iostart, gmux_data->iolen);
	574	err_free:
	575	kfree(gmux_data);
	576	return ret;
	577	}
	578
b859f159	579	static void gmux_remove(struct pnp_dev *pnp)
917ee75a SF	580	{
	581	struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
	582
76b487dd AH	583	vga_switcheroo_unregister_handler();
	584	gmux_disable_interrupts(gmux_data);
	585	if (gmux_data->gpe >= 0) {
	586	acpi_disable_gpe(NULL, gmux_data->gpe);
	587	acpi_remove_notify_handler(gmux_data->dhandle,
	588	ACPI_DEVICE_NOTIFY,
	589	&gmux_notify_handler);
	590	}
	591
917ee75a	592	backlight_device_unregister(gmux_data->bdev);
76b487dd	593
917ee75a	594	release_region(gmux_data->iostart, gmux_data->iolen);
76b487dd	595	apple_gmux_data = NULL;
917ee75a SF	596	kfree(gmux_data);
917ee75a SF	597
a60b2176	598	acpi_video_dmi_demote_vendor();
917ee75a SF	599	acpi_video_register();
	600	apple_bl_register();
	601	}
	602
	603	static const struct pnp_device_id gmux_device_ids[] = {
	604	{"APP000B", 0},
	605	{"", 0}
	606	};
	607
	608	static struct pnp_driver gmux_pnp_driver = {
	609	.name = "apple-gmux",
	610	.probe = gmux_probe,
b859f159	611	.remove = gmux_remove,
917ee75a	612	.id_table = gmux_device_ids,
76b487dd AH	613	.suspend = gmux_suspend,
76b487dd AH	614	.resume = gmux_resume
917ee75a SF	615	};
	616
	617	static int __init apple_gmux_init(void)
	618	{
	619	return pnp_register_driver(&gmux_pnp_driver);
	620	}
	621
	622	static void __exit apple_gmux_exit(void)
	623	{
	624	pnp_unregister_driver(&gmux_pnp_driver);
	625	}
	626
	627	module_init(apple_gmux_init);
	628	module_exit(apple_gmux_exit);
	629
	630	MODULE_AUTHOR("Seth Forshee <seth.forshee@canonical.com>");
	631	MODULE_DESCRIPTION("Apple Gmux Driver");
	632	MODULE_LICENSE("GPL");
	633	MODULE_DEVICE_TABLE(pnp, gmux_device_ids);