text: /*
   * Dell WMI hotkeys
   *
   * Copyright (C) 2008 Red Hat <mjg@redhat.com>
   *
   * Portions based on wistron_btns.c:
   * Copyright (C) 2005 Miloslav Trmac <mitr@volny.cz>
   * Copyright (C) 2005 Bernhard Rosenkraenzer <bero@arklinux.org>
   * Copyright (C) 2005 Dmitry Torokhov <dtor@mail.ru>
   *
   *  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/module.h>
  #include <linux/init.h>
  #include <linux/slab.h>
  #include <linux/types.h>
  #include <linux/input.h>
  #include <acpi/acpi_drivers.h>
  #include <linux/acpi.h>
  #include <linux/string.h>
  #include <linux/dmi.h>
  
  MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
  MODULE_DESCRIPTION("Dell laptop WMI hotkeys driver");
  MODULE_LICENSE("GPL");
  
  #define DELL_EVENT_GUID "9DBB5994-A997-11DA-B012-B622A1EF5492"
  
  static int acpi_video;
  
  MODULE_ALIAS("wmi:"DELL_EVENT_GUID);
  
  struct key_entry {
  	char type;		/* See KE_* below */
  	u16 code;
  	u16 keycode;
  };
  
  enum { KE_KEY, KE_SW, KE_IGNORE, KE_END };
  
  /*
   * Certain keys are flagged as KE_IGNORE. All of these are either
   * notifications (rather than requests for change) or are also sent
   * via the keyboard controller so should not be sent again.
   */
  
  static struct key_entry dell_legacy_wmi_keymap[] = {
  	{KE_KEY, 0xe045, KEY_PROG1},
  	{KE_KEY, 0xe009, KEY_EJECTCD},
  
  	/* These also contain the brightness level at offset 6 */
  	{KE_KEY, 0xe006, KEY_BRIGHTNESSUP},
  	{KE_KEY, 0xe005, KEY_BRIGHTNESSDOWN},
  
  	/* Battery health status button */
  	{KE_KEY, 0xe007, KEY_BATTERY},
  
  	/* This is actually for all radios. Although physically a
  	 * switch, the notification does not provide an indication of
  	 * state and so it should be reported as a key */
  	{KE_KEY, 0xe008, KEY_WLAN},
  
  	/* The next device is at offset 6, the active devices are at
  	   offset 8 and the attached devices at offset 10 */
  	{KE_KEY, 0xe00b, KEY_SWITCHVIDEOMODE},
  
  	{KE_IGNORE, 0xe00c, KEY_KBDILLUMTOGGLE},
  
  	/* BIOS error detected */
  	{KE_IGNORE, 0xe00d, KEY_RESERVED},
  
  	/* Wifi Catcher */
  	{KE_KEY, 0xe011, KEY_PROG2},
  
  	/* Ambient light sensor toggle */
  	{KE_IGNORE, 0xe013, KEY_RESERVED},
  
  	{KE_IGNORE, 0xe020, KEY_MUTE},
  	{KE_IGNORE, 0xe02e, KEY_VOLUMEDOWN},
  	{KE_IGNORE, 0xe030, KEY_VOLUMEUP},
  	{KE_IGNORE, 0xe033, KEY_KBDILLUMUP},
  	{KE_IGNORE, 0xe034, KEY_KBDILLUMDOWN},
  	{KE_IGNORE, 0xe03a, KEY_CAPSLOCK},
  	{KE_IGNORE, 0xe045, KEY_NUMLOCK},
  	{KE_IGNORE, 0xe046, KEY_SCROLLLOCK},
  	{KE_END, 0}
  };
  
  static bool dell_new_hk_type;
  
  struct dell_new_keymap_entry {
  	u16 scancode;
  	u16 keycode;
  };
  
  struct dell_hotkey_table {
  	struct dmi_header header;
  	struct dell_new_keymap_entry keymap[];
  
  };
  
  static struct key_entry *dell_new_wmi_keymap;
  
  static u16 bios_to_linux_keycode[256] = {
  
  	KEY_MEDIA,	KEY_NEXTSONG,	KEY_PLAYPAUSE, KEY_PREVIOUSSONG,
  	KEY_STOPCD,	KEY_UNKNOWN,	KEY_UNKNOWN,	KEY_UNKNOWN,
  	KEY_WWW,	KEY_UNKNOWN,	KEY_VOLUMEDOWN, KEY_MUTE,
  	KEY_VOLUMEUP,	KEY_UNKNOWN,	KEY_BATTERY,	KEY_EJECTCD,
  	KEY_UNKNOWN,	KEY_SLEEP,	KEY_PROG1, KEY_BRIGHTNESSDOWN,
  	KEY_BRIGHTNESSUP,	KEY_UNKNOWN,	KEY_KBDILLUMTOGGLE,
  	KEY_UNKNOWN,	KEY_SWITCHVIDEOMODE,	KEY_UNKNOWN, KEY_UNKNOWN,
  	KEY_SWITCHVIDEOMODE,	KEY_UNKNOWN,	KEY_UNKNOWN, KEY_PROG2,
  	KEY_UNKNOWN, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  	KEY_PROG3
  };
  
  
  static struct key_entry *dell_wmi_keymap = dell_legacy_wmi_keymap;
  
  static struct input_dev *dell_wmi_input_dev;
  
  static struct key_entry *dell_wmi_get_entry_by_scancode(unsigned int code)
  {
  	struct key_entry *key;
  
  	for (key = dell_wmi_keymap; key->type != KE_END; key++)
  		if (code == key->code)
  			return key;
  
  	return NULL;
  }
  
  static struct key_entry *dell_wmi_get_entry_by_keycode(unsigned int keycode)
  {
  	struct key_entry *key;
  
  	for (key = dell_wmi_keymap; key->type != KE_END; key++)
  		if (key->type == KE_KEY && keycode == key->keycode)
  			return key;
  
  	return NULL;
  }
  
  static int dell_wmi_getkeycode(struct input_dev *dev,
  				unsigned int scancode, unsigned int *keycode)
  {
  	struct key_entry *key = dell_wmi_get_entry_by_scancode(scancode);
  
  	if (key && key->type == KE_KEY) {
  		*keycode = key->keycode;
  		return 0;
  	}
  
  	return -EINVAL;
  }
  
  static int dell_wmi_setkeycode(struct input_dev *dev,
  				unsigned int scancode, unsigned int keycode)
  {
  	struct key_entry *key;
  	unsigned int old_keycode;
  
  	key = dell_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 (!dell_wmi_get_entry_by_keycode(old_keycode))
  			clear_bit(old_keycode, dev->keybit);
  		return 0;
  	}
  	return -EINVAL;
  }
  
  static void dell_wmi_notify(u32 value, void *context)
  {
  	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
  	static struct key_entry *key;
  	union acpi_object *obj;
  	acpi_status status;
  
  	status = wmi_get_event_data(value, &response);
  	if (status != AE_OK) {
  		printk(KERN_INFO "dell-wmi: bad event status 0x%x\n", status);
  		return;
  	}
  
  	obj = (union acpi_object *)response.pointer;
  
  	if (obj && obj->type == ACPI_TYPE_BUFFER) {
  		int reported_key;
  		u16 *buffer_entry = (u16 *)obj->buffer.pointer;
  		if (dell_new_hk_type && (buffer_entry[1] != 0x10)) {
  			printk(KERN_INFO "dell-wmi: Received unknown WMI event"
  					 " (0x%x)\n", buffer_entry[1]);
  			kfree(obj);
  			return;
  		}
  
  		if (dell_new_hk_type)
  			reported_key = (int)buffer_entry[2];
  		else
  			reported_key = (int)buffer_entry[1] & 0xffff;
  
  		key = dell_wmi_get_entry_by_scancode(reported_key);
  
  		if (!key) {
  			printk(KERN_INFO "dell-wmi: Unknown key %x pressed\n",
  				reported_key);
  		} else if ((key->keycode == KEY_BRIGHTNESSUP ||
  			    key->keycode == KEY_BRIGHTNESSDOWN) && acpi_video) {
  			/* Don't report brightness notifications that will also
  			 * come via ACPI */
  			;
  		} else {
  			input_report_key(dell_wmi_input_dev, key->keycode, 1);
  			input_sync(dell_wmi_input_dev);
  			input_report_key(dell_wmi_input_dev, key->keycode, 0);
  			input_sync(dell_wmi_input_dev);
  		}
  	}
  	kfree(obj);
  }
  
  
  static void setup_new_hk_map(const struct dmi_header *dm)
  {
  
  	int i;
  	int hotkey_num = (dm->length-4)/sizeof(struct dell_new_keymap_entry);
  	struct dell_hotkey_table *table =
  		container_of(dm, struct dell_hotkey_table, header);
  
  	dell_new_wmi_keymap = kzalloc((hotkey_num+1) *
  				      sizeof(struct key_entry), GFP_KERNEL);
  
  	for (i = 0; i < hotkey_num; i++) {
  		dell_new_wmi_keymap[i].type = KE_KEY;
  		dell_new_wmi_keymap[i].code = table->keymap[i].scancode;
  		dell_new_wmi_keymap[i].keycode =
  			(table->keymap[i].keycode > 255) ? 0 :
  			bios_to_linux_keycode[table->keymap[i].keycode];
  	}
  
  	dell_new_wmi_keymap[i].type = KE_END;
  	dell_new_wmi_keymap[i].code = 0;
  	dell_new_wmi_keymap[i].keycode = 0;
  
  	dell_wmi_keymap = dell_new_wmi_keymap;
  
  }
  
  
  static void find_hk_type(const struct dmi_header *dm, void *dummy)
  {
  
  	if ((dm->type == 0xb2) && (dm->length > 6)) {
  		dell_new_hk_type = true;
  		setup_new_hk_map(dm);
  	}
  
  }
  
  
  static int __init dell_wmi_input_setup(void)
  {
  	struct key_entry *key;
  	int err;
  
  	dell_wmi_input_dev = input_allocate_device();
  
  	if (!dell_wmi_input_dev)
  		return -ENOMEM;
  
  	dell_wmi_input_dev->name = "Dell WMI hotkeys";
  	dell_wmi_input_dev->phys = "wmi/input0";
  	dell_wmi_input_dev->id.bustype = BUS_HOST;
  	dell_wmi_input_dev->getkeycode = dell_wmi_getkeycode;
  	dell_wmi_input_dev->setkeycode = dell_wmi_setkeycode;
  
  	for (key = dell_wmi_keymap; key->type != KE_END; key++) {
  		switch (key->type) {
  		case KE_KEY:
  			set_bit(EV_KEY, dell_wmi_input_dev->evbit);
  			set_bit(key->keycode, dell_wmi_input_dev->keybit);
  			break;
  		case KE_SW:
  			set_bit(EV_SW, dell_wmi_input_dev->evbit);
  			set_bit(key->keycode, dell_wmi_input_dev->swbit);
  			break;
  		}
  	}
  
  	err = input_register_device(dell_wmi_input_dev);
  
  	if (err) {
  		input_free_device(dell_wmi_input_dev);
  		return err;
  	}
  
  	return 0;
  }
  
  static int __init dell_wmi_init(void)
  {
  	int err;
  	acpi_status status;
  
  	if (!wmi_has_guid(DELL_EVENT_GUID)) {
  		printk(KERN_WARNING "dell-wmi: No known WMI GUID found\n");
  		return -ENODEV;
  	}
  
  	dmi_walk(find_hk_type, NULL);
  	acpi_video = acpi_video_backlight_support();
  
  	err = dell_wmi_input_setup();
  	if (err)
  		return err;
  
  	status = wmi_install_notify_handler(DELL_EVENT_GUID,
  					 dell_wmi_notify, NULL);
  	if (ACPI_FAILURE(status)) {
  		input_unregister_device(dell_wmi_input_dev);
  		printk(KERN_ERR
  			"dell-wmi: Unable to register notify handler - %d\n",
  			status);
  		return -ENODEV;
  	}
  
  	return 0;
  }
  
  static void __exit dell_wmi_exit(void)
  {
  	wmi_remove_notify_handler(DELL_EVENT_GUID);
  	input_unregister_device(dell_wmi_input_dev);
  }
  
  module_init(dell_wmi_init);
  module_exit(dell_wmi_exit);
  