linux/drivers/platform/x86/msi-wmi.c

/*
 * MSI WMI hotkeys
 *
 * Copyright (C) 2009 Novell <trenn@suse.de>
 *
 * Most stuff taken over from hp-wmi
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */



#include <linux/kernel.h>
#include <linux/input.h>
#include <linux/acpi.h>
#include <linux/backlight.h>

MODULE_AUTHOR("Thomas Renninger <trenn@suse.de>");
MODULE_DESCRIPTION("MSI laptop WMI hotkeys driver");
MODULE_LICENSE("GPL");

MODULE_ALIAS("wmi:551A1F84-FBDD-4125-91DB-3EA8F44F1D45");
MODULE_ALIAS("wmi:B6F3EEF2-3D2F-49DC-9DE3-85BCE18C62F2");

/* Temporary workaround until the WMI sysfs interface goes in
		{ "svn", DMI_SYS_VENDOR },
		{ "pn",  DMI_PRODUCT_NAME },
		{ "pvr", DMI_PRODUCT_VERSION },
		{ "rvn", DMI_BOARD_VENDOR },
		{ "rn",  DMI_BOARD_NAME },
*/

MODULE_ALIAS("dmi:*:svnMICRO-STARINTERNATIONAL*:pnMS-6638:*");

#define DRV_NAME "msi-wmi"
#define DRV_PFX DRV_NAME ": "

#define MSIWMI_BIOS_GUID "551A1F84-FBDD-4125-91DB-3EA8F44F1D45"
#define MSIWMI_EVENT_GUID "B6F3EEF2-3D2F-49DC-9DE3-85BCE18C62F2"

#define dprintk(msg...) pr_debug(DRV_PFX msg)

struct key_entry {
	char type;		/* See KE_* below */
	u16 code;
	u16 keycode;
	int instance;
	ktime_t last_pressed;
};

/*
 * KE_KEY the only used key type, but keep this, others might also
 * show up in the future. Compare with hp-wmi.c
 */
enum { KE_KEY, KE_END };

static struct key_entry msi_wmi_keymap[] = {
	{ KE_KEY, 0xd0, KEY_BRIGHTNESSUP,   0, {0, } },
	{ KE_KEY, 0xd1, KEY_BRIGHTNESSDOWN, 1, {0, } },
	{ KE_KEY, 0xd2, KEY_VOLUMEUP,	2, {0, } },
	{ KE_KEY, 0xd3, KEY_VOLUMEDOWN,	3, {0, } },
	{ KE_END, 0}
};

struct backlight_device *backlight;

static int backlight_map[] = { 0x00, 0x33, 0x66, 0x99, 0xCC, 0xFF };

static struct input_dev *msi_wmi_input_dev;

static int msi_wmi_query_block(int instance, int *ret)
{
	acpi_status status;
	union acpi_object *obj;

	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };

	status = wmi_query_block(MSIWMI_BIOS_GUID, instance, &output);

	obj = output.pointer;

	if (!obj || obj->type != ACPI_TYPE_INTEGER) {
		if (obj) {
			printk(KERN_ERR DRV_PFX "query block returned object "
			       "type: %d - buffer length:%d\n", obj->type,
			       obj->type == ACPI_TYPE_BUFFER ?
			       obj->buffer.length : 0);
		}
		kfree(obj);
		return -EINVAL;
	}
	*ret = obj->integer.value;
	kfree(obj);
	return 0;
}

static int msi_wmi_set_block(int instance, int value)
{
	acpi_status status;

	struct acpi_buffer input = { sizeof(int), &value };

	dprintk("Going to set block of instance: %d - value: %d\n",
		instance, value);

	status = wmi_set_block(MSIWMI_BIOS_GUID, instance, &input);

	return ACPI_SUCCESS(status) ? 0 : 1;
}

static int bl_get(struct backlight_device *bd)
{
	int level, err, ret = 0;

	/* Instance 1 is "get backlight", cmp with DSDT */
	err = msi_wmi_query_block(1, &ret);
	if (err)
		printk(KERN_ERR DRV_PFX "Could not query backlight: %d\n", err);
	dprintk("Get: Query block returned: %d\n", ret);
	for (level = 0; level < ARRAY_SIZE(backlight_map); level++) {
		if (backlight_map[level] == ret) {
			dprintk("Current backlight level: 0x%X - index: %d\n",
				backlight_map[level], level);
			break;
		}
	}
	if (level == ARRAY_SIZE(backlight_map)) {
		printk(KERN_ERR DRV_PFX "get: Invalid brightness value: 0x%X\n",
		       ret);
		return -EINVAL;
	}
	return level;
}

static int bl_set_status(struct backlight_device *bd)
{
	int bright = bd->props.brightness;
	if (bright >= ARRAY_SIZE(backlight_map) || bright < 0)
		return -EINVAL;

	/* Instance 0 is "set backlight" */
	return msi_wmi_set_block(0, backlight_map[bright]);
}

static struct backlight_ops msi_backlight_ops = {
	.get_brightness	= bl_get,
	.update_status	= bl_set_status,
};

static struct key_entry *msi_wmi_get_entry_by_scancode(int code)
{
	struct key_entry *key;

	for (key = msi_wmi_keymap; key->type != KE_END; key++)
		if (code == key->code)
			return key;

	return NULL;
}

static struct key_entry *msi_wmi_get_entry_by_keycode(int keycode)
{
	struct key_entry *key;

	for (key = msi_wmi_keymap; key->type != KE_END; key++)
		if (key->type == KE_KEY && keycode == key->keycode)
			return key;

	return NULL;
}

static int msi_wmi_getkeycode(struct input_dev *dev, int scancode, int *keycode)
{
	struct key_entry *key = msi_wmi_get_entry_by_scancode(scancode);

	if (key && key->type == KE_KEY) {
		*keycode = key->keycode;
		return 0;
	}

	return -EINVAL;
}

static int msi_wmi_setkeycode(struct input_dev *dev, int scancode, int keycode)
{
	struct key_entry *key;
	int old_keycode;

	if (keycode < 0 || keycode > KEY_MAX)
		return -EINVAL;

	key = msi_wmi_get_entry_by_scancode(scancode);
	if (key && key->type == KE_KEY) {
		old_keycode = key->keycode;
		key->keycode = keycode;
		set_bit(keycode, dev->keybit);
		if (!msi_wmi_get_entry_by_keycode(old_keycode))
			clear_bit(old_keycode, dev->keybit);
		return 0;
	}

	return -EINVAL;
}

static void msi_wmi_notify(u32 value, void *context)
{
	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
	static struct key_entry *key;
	union acpi_object *obj;
	ktime_t cur;

	wmi_get_event_data(value, &response);

	obj = (union acpi_object *)response.pointer;

	if (obj && obj->type == ACPI_TYPE_INTEGER) {
		int eventcode = obj->integer.value;
		dprintk("Eventcode: 0x%x\n", eventcode);
		key = msi_wmi_get_entry_by_scancode(eventcode);
		if (key) {
			cur = ktime_get_real();
			/* Ignore event if the same event happened in a 50 ms
			   timeframe -> Key press may result in 10-20 GPEs */
			if (ktime_to_us(ktime_sub(cur, key->last_pressed))
			    < 1000 * 50) {
				dprintk("Suppressed key event 0x%X - "
					"Last press was %lld us ago\n",
					 key->code,
					 ktime_to_us(ktime_sub(cur,
						       key->last_pressed)));
				return;
			}
			key->last_pressed = cur;

			switch (key->type) {
			case KE_KEY:
				/* Brightness is served via acpi video driver */
				if (!backlight &&
				    (key->keycode == KEY_BRIGHTNESSUP ||
				     key->keycode == KEY_BRIGHTNESSDOWN))
					break;

				dprintk("Send key: 0x%X - "
					"Input layer keycode: %d\n", key->code,
					 key->keycode);
				input_report_key(msi_wmi_input_dev,
						 key->keycode, 1);
				input_sync(msi_wmi_input_dev);
				input_report_key(msi_wmi_input_dev,
						 key->keycode, 0);
				input_sync(msi_wmi_input_dev);
				break;
			}
		} else
			printk(KERN_INFO "Unknown key pressed - %x\n",
			       eventcode);
	} else
		printk(KERN_INFO DRV_PFX "Unknown event received\n");
	kfree(response.pointer);
}

static int __init msi_wmi_input_setup(void)
{
	struct key_entry *key;
	int err;

	msi_wmi_input_dev = input_allocate_device();
	if (!msi_wmi_input_dev)
		return -ENOMEM;

	msi_wmi_input_dev->name = "MSI WMI hotkeys";
	msi_wmi_input_dev->phys = "wmi/input0";
	msi_wmi_input_dev->id.bustype = BUS_HOST;
	msi_wmi_input_dev->getkeycode = msi_wmi_getkeycode;
	msi_wmi_input_dev->setkeycode = msi_wmi_setkeycode;

	for (key = msi_wmi_keymap; key->type != KE_END; key++) {
		switch (key->type) {
		case KE_KEY:
			set_bit(EV_KEY, msi_wmi_input_dev->evbit);
			set_bit(key->keycode, msi_wmi_input_dev->keybit);
			break;
		}
	}

	err = input_register_device(msi_wmi_input_dev);

	if (err) {
		input_free_device(msi_wmi_input_dev);
		return err;
	}

	return 0;
}

static int __init msi_wmi_init(void)
{
	int err;

	if (!wmi_has_guid(MSIWMI_EVENT_GUID)) {
		printk(KERN_ERR
		       "This machine doesn't have MSI-hotkeys through WMI\n");
		return -ENODEV;
	}
	err = wmi_install_notify_handler(MSIWMI_EVENT_GUID,
			msi_wmi_notify, NULL);
	if (err)
		return -EINVAL;

	err = msi_wmi_input_setup();
	if (err)
		goto err_uninstall_notifier;

	if (!acpi_video_backlight_support()) {
		backlight = backlight_device_register(DRV_NAME,
				NULL, NULL, &msi_backlight_ops);
		if (IS_ERR(backlight))
			goto err_free_input;

		backlight->props.max_brightness = ARRAY_SIZE(backlight_map) - 1;
		err = bl_get(NULL);
		if (err < 0)
			goto err_free_backlight;

		backlight->props.brightness = err;
	}
	dprintk("Event handler installed\n");

	return 0;

err_free_backlight:
	backlight_device_unregister(backlight);
err_free_input:
	input_unregister_device(msi_wmi_input_dev);
err_uninstall_notifier:
	wmi_remove_notify_handler(MSIWMI_EVENT_GUID);
	return err;
}

static void __exit msi_wmi_exit(void)
{
	if (wmi_has_guid(MSIWMI_EVENT_GUID)) {
		wmi_remove_notify_handler(MSIWMI_EVENT_GUID);
		input_unregister_device(msi_wmi_input_dev);
		backlight_device_unregister(backlight);
	}
}

module_init(msi_wmi_init);
module_exit(msi_wmi_exit);