misc: add HP WMI laptop extras driver

This driver adds support for reading and configuring certain information
on modern HP laptops with WMI BIOS interfaces.  It supports enabling and
disabling the ambient light sensor, querying attached displays and hard
drive temperature, sending events on docking and querying the state of the
dock and toggling the state of the wifi, bluetooth and wwan hardware via
rfkill.  It also makes the little "(i)" button work on machines that send
that via WMI rather than via the keyboard controller.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index d5bc288b..1689c05 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -212,6 +212,18 @@
 	  This is a driver for the WMI extensions (wireless and bluetooth power
 	  control) of the HP Compaq TC1100 tablet.
 
+config HP_WMI
+       tristate "HP WMI extras"
+       depends on ACPI_WMI
+       depends on INPUT
+       depends on RFKILL
+       help
+         Say Y here if you want to support WMI-based hotkeys on HP laptops and
+	 to read data from WMI such as docking or ambient light sensor state.
+
+         To compile this driver as a module, choose M here: the module will
+         be called hp-wmi.
+
 config MSI_LAPTOP
         tristate "MSI Laptop Extras"
         depends on X86
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 688fe76..f5e2734 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -13,6 +13,7 @@
 obj-$(CONFIG_ATMEL_PWM)		+= atmel_pwm.o
 obj-$(CONFIG_ATMEL_SSC)		+= atmel-ssc.o
 obj-$(CONFIG_ATMEL_TCLIB)	+= atmel_tclib.o
+obj-$(CONFIG_HP_WMI)		+= hp-wmi.o
 obj-$(CONFIG_TC1100_WMI)	+= tc1100-wmi.o
 obj-$(CONFIG_LKDTM)		+= lkdtm.o
 obj-$(CONFIG_TIFM_CORE)       	+= tifm_core.o
diff --git a/drivers/misc/hp-wmi.c b/drivers/misc/hp-wmi.c
new file mode 100644
index 0000000..1dbcbcb
--- /dev/null
+++ b/drivers/misc/hp-wmi.c
@@ -0,0 +1,494 @@
+/*
+ * HP 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/types.h>
+#include <linux/input.h>
+#include <acpi/acpi_drivers.h>
+#include <linux/platform_device.h>
+#include <linux/acpi.h>
+#include <linux/rfkill.h>
+#include <linux/string.h>
+
+MODULE_AUTHOR("Matthew Garrett <mjg59@srcf.ucam.org>");
+MODULE_DESCRIPTION("HP laptop WMI hotkeys driver");
+MODULE_LICENSE("GPL");
+
+MODULE_ALIAS("wmi:95F24279-4D7B-4334-9387-ACCDC67EF61C");
+MODULE_ALIAS("wmi:5FB7F034-2C63-45e9-BE91-3D44E2C707E4");
+
+#define HPWMI_EVENT_GUID "95F24279-4D7B-4334-9387-ACCDC67EF61C"
+#define HPWMI_BIOS_GUID "5FB7F034-2C63-45e9-BE91-3D44E2C707E4"
+
+#define HPWMI_DISPLAY_QUERY 0x1
+#define HPWMI_HDDTEMP_QUERY 0x2
+#define HPWMI_ALS_QUERY 0x3
+#define HPWMI_DOCK_QUERY 0x4
+#define HPWMI_WIRELESS_QUERY 0x5
+
+static int __init hp_wmi_bios_setup(struct platform_device *device);
+static int __exit hp_wmi_bios_remove(struct platform_device *device);
+
+struct bios_args {
+	u32 signature;
+	u32 command;
+	u32 commandtype;
+	u32 datasize;
+	u32 data;
+};
+
+struct bios_return {
+	u32 sigpass;
+	u32 return_code;
+	u32 value;
+};
+
+struct key_entry {
+	char type;		/* See KE_* below */
+	u8 code;
+	u16 keycode;
+};
+
+enum { KE_KEY, KE_SW, KE_END };
+
+static struct key_entry hp_wmi_keymap[] = {
+	{KE_SW, 0x01, SW_DOCK},
+	{KE_KEY, 0x02, KEY_BRIGHTNESSUP},
+	{KE_KEY, 0x03, KEY_BRIGHTNESSDOWN},
+	{KE_KEY, 0x04, KEY_HELP},
+	{KE_END, 0}
+};
+
+static struct input_dev *hp_wmi_input_dev;
+static struct platform_device *hp_wmi_platform_dev;
+
+static struct rfkill *wifi_rfkill;
+static struct rfkill *bluetooth_rfkill;
+static struct rfkill *wwan_rfkill;
+
+static struct platform_driver hp_wmi_driver = {
+	.driver = {
+		   .name = "hp-wmi",
+		   .owner = THIS_MODULE,
+	},
+	.probe = hp_wmi_bios_setup,
+	.remove = hp_wmi_bios_remove,
+};
+
+static int hp_wmi_perform_query(int query, int write, int value)
+{
+	struct bios_return bios_return;
+	acpi_status status;
+	union acpi_object *obj;
+	struct bios_args args = {
+		.signature = 0x55434553,
+		.command = write ? 0x2 : 0x1,
+		.commandtype = query,
+		.datasize = write ? 0x4 : 0,
+		.data = value,
+	};
+	struct acpi_buffer input = { sizeof(struct bios_args), &args };
+	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+
+	status = wmi_evaluate_method(HPWMI_BIOS_GUID, 0, 0x3, &input, &output);
+
+	obj = output.pointer;
+
+	if (!obj || obj->type != ACPI_TYPE_BUFFER)
+		return -EINVAL;
+
+	bios_return = *((struct bios_return *)obj->buffer.pointer);
+	if (bios_return.return_code > 0)
+		return bios_return.return_code * -1;
+	else
+		return bios_return.value;
+}
+
+static int hp_wmi_display_state(void)
+{
+	return hp_wmi_perform_query(HPWMI_DISPLAY_QUERY, 0, 0);
+}
+
+static int hp_wmi_hddtemp_state(void)
+{
+	return hp_wmi_perform_query(HPWMI_HDDTEMP_QUERY, 0, 0);
+}
+
+static int hp_wmi_als_state(void)
+{
+	return hp_wmi_perform_query(HPWMI_ALS_QUERY, 0, 0);
+}
+
+static int hp_wmi_dock_state(void)
+{
+	return hp_wmi_perform_query(HPWMI_DOCK_QUERY, 0, 0);
+}
+
+static int hp_wmi_wifi_set(void *data, enum rfkill_state state)
+{
+	if (state)
+		return hp_wmi_perform_query(HPWMI_WIRELESS_QUERY, 1, 0x101);
+	else
+		return hp_wmi_perform_query(HPWMI_WIRELESS_QUERY, 1, 0x100);
+}
+
+static int hp_wmi_bluetooth_set(void *data, enum rfkill_state state)
+{
+	if (state)
+		return hp_wmi_perform_query(HPWMI_WIRELESS_QUERY, 1, 0x202);
+	else
+		return hp_wmi_perform_query(HPWMI_WIRELESS_QUERY, 1, 0x200);
+}
+
+static int hp_wmi_wwan_set(void *data, enum rfkill_state state)
+{
+	if (state)
+		return hp_wmi_perform_query(HPWMI_WIRELESS_QUERY, 1, 0x404);
+	else
+		return hp_wmi_perform_query(HPWMI_WIRELESS_QUERY, 1, 0x400);
+}
+
+static int hp_wmi_wifi_state(void)
+{
+	int wireless = hp_wmi_perform_query(HPWMI_WIRELESS_QUERY, 0, 0);
+
+	if (wireless & 0x100)
+		return 1;
+	else
+		return 0;
+}
+
+static int hp_wmi_bluetooth_state(void)
+{
+	int wireless = hp_wmi_perform_query(HPWMI_WIRELESS_QUERY, 0, 0);
+
+	if (wireless & 0x10000)
+		return 1;
+	else
+		return 0;
+}
+
+static int hp_wmi_wwan_state(void)
+{
+	int wireless = hp_wmi_perform_query(HPWMI_WIRELESS_QUERY, 0, 0);
+
+	if (wireless & 0x1000000)
+		return 1;
+	else
+		return 0;
+}
+
+static ssize_t show_display(struct device *dev, struct device_attribute *attr,
+			    char *buf)
+{
+	int value = hp_wmi_display_state();
+	if (value < 0)
+		return -EINVAL;
+	return sprintf(buf, "%d\n", value);
+}
+
+static ssize_t show_hddtemp(struct device *dev, struct device_attribute *attr,
+			    char *buf)
+{
+	int value = hp_wmi_hddtemp_state();
+	if (value < 0)
+		return -EINVAL;
+	return sprintf(buf, "%d\n", value);
+}
+
+static ssize_t show_als(struct device *dev, struct device_attribute *attr,
+			char *buf)
+{
+	int value = hp_wmi_als_state();
+	if (value < 0)
+		return -EINVAL;
+	return sprintf(buf, "%d\n", value);
+}
+
+static ssize_t show_dock(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	int value = hp_wmi_dock_state();
+	if (value < 0)
+		return -EINVAL;
+	return sprintf(buf, "%d\n", value);
+}
+
+static ssize_t set_als(struct device *dev, struct device_attribute *attr,
+		       const char *buf, size_t count)
+{
+	u32 tmp = simple_strtoul(buf, NULL, 10);
+	hp_wmi_perform_query(HPWMI_ALS_QUERY, 1, tmp);
+	return count;
+}
+
+static DEVICE_ATTR(display, S_IRUGO, show_display, NULL);
+static DEVICE_ATTR(hddtemp, S_IRUGO, show_hddtemp, NULL);
+static DEVICE_ATTR(als, S_IRUGO | S_IWUSR, show_als, set_als);
+static DEVICE_ATTR(dock, S_IRUGO, show_dock, NULL);
+
+static struct key_entry *hp_wmi_get_entry_by_scancode(int code)
+{
+	struct key_entry *key;
+
+	for (key = hp_wmi_keymap; key->type != KE_END; key++)
+		if (code == key->code)
+			return key;
+
+	return NULL;
+}
+
+static struct key_entry *hp_wmi_get_entry_by_keycode(int keycode)
+{
+	struct key_entry *key;
+
+	for (key = hp_wmi_keymap; key->type != KE_END; key++)
+		if (key->type == KE_KEY && keycode == key->keycode)
+			return key;
+
+	return NULL;
+}
+
+static int hp_wmi_getkeycode(struct input_dev *dev, int scancode, int *keycode)
+{
+	struct key_entry *key = hp_wmi_get_entry_by_scancode(scancode);
+
+	if (key && key->type == KE_KEY) {
+		*keycode = key->keycode;
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static int hp_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 = hp_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 (!hp_wmi_get_entry_by_keycode(old_keycode))
+			clear_bit(old_keycode, dev->keybit);
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+void hp_wmi_notify(u32 value, void *context)
+{
+	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
+	static struct key_entry *key;
+	union acpi_object *obj;
+
+	wmi_get_event_data(value, &response);
+
+	obj = (union acpi_object *)response.pointer;
+
+	if (obj && obj->type == ACPI_TYPE_BUFFER && obj->buffer.length == 8) {
+		int eventcode = *((u8 *) obj->buffer.pointer);
+		key = hp_wmi_get_entry_by_scancode(eventcode);
+		if (key) {
+			switch (key->type) {
+			case KE_KEY:
+				input_report_key(hp_wmi_input_dev,
+						 key->keycode, 1);
+				input_sync(hp_wmi_input_dev);
+				input_report_key(hp_wmi_input_dev,
+						 key->keycode, 0);
+				input_sync(hp_wmi_input_dev);
+				break;
+			case KE_SW:
+				input_report_switch(hp_wmi_input_dev,
+						    key->keycode,
+						    hp_wmi_dock_state());
+				input_sync(hp_wmi_input_dev);
+				break;
+			}
+		} else if (eventcode == 0x5) {
+			if (wifi_rfkill)
+				wifi_rfkill->state = hp_wmi_wifi_state();
+			if (bluetooth_rfkill)
+				bluetooth_rfkill->state =
+				    hp_wmi_bluetooth_state();
+			if (wwan_rfkill)
+				wwan_rfkill->state = hp_wmi_wwan_state();
+		} else
+			printk(KERN_INFO "HP WMI: Unknown key pressed - %x\n",
+			       eventcode);
+	} else
+		printk(KERN_INFO "HP WMI: Unknown response received\n");
+}
+
+static int __init hp_wmi_input_setup(void)
+{
+	struct key_entry *key;
+	int err;
+
+	hp_wmi_input_dev = input_allocate_device();
+
+	hp_wmi_input_dev->name = "HP WMI hotkeys";
+	hp_wmi_input_dev->phys = "wmi/input0";
+	hp_wmi_input_dev->id.bustype = BUS_HOST;
+	hp_wmi_input_dev->getkeycode = hp_wmi_getkeycode;
+	hp_wmi_input_dev->setkeycode = hp_wmi_setkeycode;
+
+	for (key = hp_wmi_keymap; key->type != KE_END; key++) {
+		switch (key->type) {
+		case KE_KEY:
+			set_bit(EV_KEY, hp_wmi_input_dev->evbit);
+			set_bit(key->keycode, hp_wmi_input_dev->keybit);
+			break;
+		case KE_SW:
+			set_bit(EV_SW, hp_wmi_input_dev->evbit);
+			set_bit(key->keycode, hp_wmi_input_dev->swbit);
+			break;
+		}
+	}
+
+	err = input_register_device(hp_wmi_input_dev);
+
+	if (err) {
+		input_free_device(hp_wmi_input_dev);
+		return err;
+	}
+
+	return 0;
+}
+
+static void cleanup_sysfs(struct platform_device *device)
+{
+	device_remove_file(&device->dev, &dev_attr_display);
+	device_remove_file(&device->dev, &dev_attr_hddtemp);
+	device_remove_file(&device->dev, &dev_attr_als);
+	device_remove_file(&device->dev, &dev_attr_dock);
+}
+
+static int __init hp_wmi_bios_setup(struct platform_device *device)
+{
+	int err;
+
+	err = device_create_file(&device->dev, &dev_attr_display);
+	if (err)
+		goto add_sysfs_error;
+	err = device_create_file(&device->dev, &dev_attr_hddtemp);
+	if (err)
+		goto add_sysfs_error;
+	err = device_create_file(&device->dev, &dev_attr_als);
+	if (err)
+		goto add_sysfs_error;
+	err = device_create_file(&device->dev, &dev_attr_dock);
+	if (err)
+		goto add_sysfs_error;
+
+	wifi_rfkill = rfkill_allocate(&device->dev, RFKILL_TYPE_WLAN);
+	wifi_rfkill->name = "hp-wifi";
+	wifi_rfkill->state = hp_wmi_wifi_state();
+	wifi_rfkill->toggle_radio = hp_wmi_wifi_set;
+	wifi_rfkill->user_claim_unsupported = 1;
+
+	bluetooth_rfkill = rfkill_allocate(&device->dev,
+					   RFKILL_TYPE_BLUETOOTH);
+	bluetooth_rfkill->name = "hp-bluetooth";
+	bluetooth_rfkill->state = hp_wmi_bluetooth_state();
+	bluetooth_rfkill->toggle_radio = hp_wmi_bluetooth_set;
+	bluetooth_rfkill->user_claim_unsupported = 1;
+
+	wwan_rfkill = rfkill_allocate(&device->dev, RFKILL_TYPE_WIMAX);
+	wwan_rfkill->name = "hp-wwan";
+	wwan_rfkill->state = hp_wmi_wwan_state();
+	wwan_rfkill->toggle_radio = hp_wmi_wwan_set;
+	wwan_rfkill->user_claim_unsupported = 1;
+
+	rfkill_register(wifi_rfkill);
+	rfkill_register(bluetooth_rfkill);
+	rfkill_register(wwan_rfkill);
+
+	return 0;
+add_sysfs_error:
+	cleanup_sysfs(device);
+	return err;
+}
+
+static int __exit hp_wmi_bios_remove(struct platform_device *device)
+{
+	cleanup_sysfs(device);
+
+	rfkill_unregister(wifi_rfkill);
+	rfkill_unregister(bluetooth_rfkill);
+	rfkill_unregister(wwan_rfkill);
+
+	return 0;
+}
+
+static int __init hp_wmi_init(void)
+{
+	int err;
+
+	if (wmi_has_guid(HPWMI_EVENT_GUID)) {
+		err = wmi_install_notify_handler(HPWMI_EVENT_GUID,
+						 hp_wmi_notify, NULL);
+		if (!err)
+			hp_wmi_input_setup();
+	}
+
+	if (wmi_has_guid(HPWMI_BIOS_GUID)) {
+		err = platform_driver_register(&hp_wmi_driver);
+		if (err)
+			return 0;
+		hp_wmi_platform_dev = platform_device_alloc("hp-wmi", -1);
+		if (!hp_wmi_platform_dev) {
+			platform_driver_unregister(&hp_wmi_driver);
+			return 0;
+		}
+		platform_device_add(hp_wmi_platform_dev);
+	}
+
+	return 0;
+}
+
+static void __exit hp_wmi_exit(void)
+{
+	if (wmi_has_guid(HPWMI_EVENT_GUID)) {
+		wmi_remove_notify_handler(HPWMI_EVENT_GUID);
+		input_unregister_device(hp_wmi_input_dev);
+	}
+	if (hp_wmi_platform_dev) {
+		platform_device_del(hp_wmi_platform_dev);
+		platform_driver_unregister(&hp_wmi_driver);
+	}
+}
+
+module_init(hp_wmi_init);
+module_exit(hp_wmi_exit);