topstar-laptop: add new driver for hotkeys support on Topstar N01

This adds Topstar Laptop Extras ACPI driver. It enables hotkeys
functionality with Topstar N01 netbook. Besides hotkeys there are
other functions exposed by its ACPI firmware, but for now only
hotkeys reporting on Topstar N01 is supported. Topstar is a chinese
manufacturer, its website can be currently reached at
http://www.topstardigital.cn/

Signed-off-by: Herton Ronaldo Krzesinski <herton@mandriva.com.br>
Reviewed-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Reviewed-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/MAINTAINERS b/MAINTAINERS
index 8dca9d8..d75a7a7 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4968,6 +4968,11 @@
 S:	Maintained
 F:	security/tomoyo/
 
+TOPSTAR LAPTOP EXTRAS DRIVER
+M:	Herton Ronaldo Krzesinski <herton@mandriva.com.br>
+S:	Maintained
+F:	drivers/platform/x86/topstar-laptop.c
+
 TOSHIBA ACPI EXTRAS DRIVER
 S:	Orphan
 F:	drivers/platform/x86/toshiba_acpi.c
diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 77c6097..4831562 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -396,6 +396,15 @@
 	  NOTE: This driver is deprecated and will probably be removed soon,
 	  use asus-laptop instead.
 
+config TOPSTAR_LAPTOP
+	tristate "Topstar Laptop Extras"
+	depends on ACPI
+	depends on INPUT
+	---help---
+	  This driver adds support for hotkeys found on Topstar laptops.
+
+	  If you have a Topstar laptop, say Y or M here.
+
 config ACPI_TOSHIBA
 	tristate "Toshiba Laptop Extras"
 	depends on ACPI
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index 641b8bf..d1c1621 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -19,4 +19,5 @@
 obj-$(CONFIG_INTEL_MENLOW)	+= intel_menlow.o
 obj-$(CONFIG_ACPI_WMI)		+= wmi.o
 obj-$(CONFIG_ACPI_ASUS)		+= asus_acpi.o
+obj-$(CONFIG_TOPSTAR_LAPTOP)	+= topstar-laptop.o
 obj-$(CONFIG_ACPI_TOSHIBA)	+= toshiba_acpi.o
diff --git a/drivers/platform/x86/topstar-laptop.c b/drivers/platform/x86/topstar-laptop.c
new file mode 100644
index 0000000..02f3d4e
--- /dev/null
+++ b/drivers/platform/x86/topstar-laptop.c
@@ -0,0 +1,265 @@
+/*
+ * ACPI driver for Topstar notebooks (hotkeys support only)
+ *
+ * Copyright (c) 2009 Herton Ronaldo Krzesinski <herton@mandriva.com.br>
+ *
+ * Implementation inspired by existing x86 platform drivers, in special
+ * asus/eepc/fujitsu-laptop, thanks to their authors
+ *
+ * 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/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/acpi.h>
+#include <linux/input.h>
+
+#define ACPI_TOPSTAR_CLASS "topstar"
+
+struct topstar_hkey {
+	struct input_dev *inputdev;
+};
+
+struct tps_key_entry {
+	u8 code;
+	u16 keycode;
+};
+
+static struct tps_key_entry topstar_keymap[] = {
+	{ 0x80, KEY_BRIGHTNESSUP },
+	{ 0x81, KEY_BRIGHTNESSDOWN },
+	{ 0x83, KEY_VOLUMEUP },
+	{ 0x84, KEY_VOLUMEDOWN },
+	{ 0x85, KEY_MUTE },
+	{ 0x86, KEY_SWITCHVIDEOMODE },
+	{ 0x87, KEY_F13 }, /* touchpad enable/disable key */
+	{ 0x88, KEY_WLAN },
+	{ 0x8a, KEY_WWW },
+	{ 0x8b, KEY_MAIL },
+	{ 0x8c, KEY_MEDIA },
+	{ 0x96, KEY_F14 }, /* G key? */
+	{ }
+};
+
+static struct tps_key_entry *tps_get_key_by_scancode(int code)
+{
+	struct tps_key_entry *key;
+
+	for (key = topstar_keymap; key->code; key++)
+		if (code == key->code)
+			return key;
+
+	return NULL;
+}
+
+static struct tps_key_entry *tps_get_key_by_keycode(int code)
+{
+	struct tps_key_entry *key;
+
+	for (key = topstar_keymap; key->code; key++)
+		if (code == key->keycode)
+			return key;
+
+	return NULL;
+}
+
+static void acpi_topstar_notify(struct acpi_device *device, u32 event)
+{
+	struct tps_key_entry *key;
+	static bool dup_evnt[2];
+	bool *dup;
+	struct topstar_hkey *hkey = acpi_driver_data(device);
+
+	/* 0x83 and 0x84 key events comes duplicated... */
+	if (event == 0x83 || event == 0x84) {
+		dup = &dup_evnt[event - 0x83];
+		if (*dup) {
+			*dup = false;
+			return;
+		}
+		*dup = true;
+	}
+
+	/*
+	 * 'G key' generate two event codes, convert to only
+	 * one event/key code for now (3G switch?)
+	 */
+	if (event == 0x97)
+		event = 0x96;
+
+	key = tps_get_key_by_scancode(event);
+	if (key) {
+		input_report_key(hkey->inputdev, key->keycode, 1);
+		input_sync(hkey->inputdev);
+		input_report_key(hkey->inputdev, key->keycode, 0);
+		input_sync(hkey->inputdev);
+		return;
+	}
+
+	/* Known non hotkey events don't handled or that we don't care yet */
+	if (event == 0x8e || event == 0x8f || event == 0x90)
+		return;
+
+	pr_info("unknown event = 0x%02x\n", event);
+}
+
+static int acpi_topstar_fncx_switch(struct acpi_device *device, bool state)
+{
+	acpi_status status;
+	union acpi_object fncx_params[1] = {
+		{ .type = ACPI_TYPE_INTEGER }
+	};
+	struct acpi_object_list fncx_arg_list = { 1, &fncx_params[0] };
+
+	fncx_params[0].integer.value = state ? 0x86 : 0x87;
+	status = acpi_evaluate_object(device->handle, "FNCX", &fncx_arg_list, NULL);
+	if (ACPI_FAILURE(status)) {
+		pr_err("Unable to switch FNCX notifications\n");
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int topstar_getkeycode(struct input_dev *dev, int scancode, int *keycode)
+{
+	struct tps_key_entry *key = tps_get_key_by_scancode(scancode);
+
+	if (!key)
+		return -EINVAL;
+
+	*keycode = key->keycode;
+	return 0;
+}
+
+static int topstar_setkeycode(struct input_dev *dev, int scancode, int keycode)
+{
+	struct tps_key_entry *key;
+	int old_keycode;
+
+	if (keycode < 0 || keycode > KEY_MAX)
+		return -EINVAL;
+
+	key = tps_get_key_by_scancode(scancode);
+
+	if (!key)
+		return -EINVAL;
+
+	old_keycode = key->keycode;
+	key->keycode = keycode;
+	set_bit(keycode, dev->keybit);
+	if (!tps_get_key_by_keycode(old_keycode))
+		clear_bit(old_keycode, dev->keybit);
+	return 0;
+}
+
+static int acpi_topstar_init_hkey(struct topstar_hkey *hkey)
+{
+	struct tps_key_entry *key;
+
+	hkey->inputdev = input_allocate_device();
+	if (!hkey->inputdev) {
+		pr_err("Unable to allocate input device\n");
+		return -ENODEV;
+	}
+	hkey->inputdev->name = "Topstar Laptop extra buttons";
+	hkey->inputdev->phys = "topstar/input0";
+	hkey->inputdev->id.bustype = BUS_HOST;
+	hkey->inputdev->getkeycode = topstar_getkeycode;
+	hkey->inputdev->setkeycode = topstar_setkeycode;
+	for (key = topstar_keymap; key->code; key++) {
+		set_bit(EV_KEY, hkey->inputdev->evbit);
+		set_bit(key->keycode, hkey->inputdev->keybit);
+	}
+	if (input_register_device(hkey->inputdev)) {
+		pr_err("Unable to register input device\n");
+		input_free_device(hkey->inputdev);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int acpi_topstar_add(struct acpi_device *device)
+{
+	struct topstar_hkey *tps_hkey;
+
+	tps_hkey = kzalloc(sizeof(struct topstar_hkey), GFP_KERNEL);
+	if (!tps_hkey)
+		return -ENOMEM;
+
+	strcpy(acpi_device_name(device), "Topstar TPSACPI");
+	strcpy(acpi_device_class(device), ACPI_TOPSTAR_CLASS);
+
+	if (acpi_topstar_fncx_switch(device, true))
+		goto add_err;
+
+	if (acpi_topstar_init_hkey(tps_hkey))
+		goto add_err;
+
+	device->driver_data = tps_hkey;
+	return 0;
+
+add_err:
+	kfree(tps_hkey);
+	return -ENODEV;
+}
+
+static int acpi_topstar_remove(struct acpi_device *device, int type)
+{
+	struct topstar_hkey *tps_hkey = acpi_driver_data(device);
+
+	acpi_topstar_fncx_switch(device, false);
+
+	input_unregister_device(tps_hkey->inputdev);
+	kfree(tps_hkey);
+
+	return 0;
+}
+
+static const struct acpi_device_id topstar_device_ids[] = {
+	{ "TPSACPI01", 0 },
+	{ "", 0 },
+};
+MODULE_DEVICE_TABLE(acpi, topstar_device_ids);
+
+static struct acpi_driver acpi_topstar_driver = {
+	.name = "Topstar laptop ACPI driver",
+	.class = ACPI_TOPSTAR_CLASS,
+	.ids = topstar_device_ids,
+	.ops = {
+		.add = acpi_topstar_add,
+		.remove = acpi_topstar_remove,
+		.notify = acpi_topstar_notify,
+	},
+};
+
+static int __init topstar_laptop_init(void)
+{
+	int ret;
+
+	ret = acpi_bus_register_driver(&acpi_topstar_driver);
+	if (ret < 0)
+		return ret;
+
+	printk(KERN_INFO "Topstar Laptop ACPI extras driver loaded\n");
+
+	return 0;
+}
+
+static void __exit topstar_laptop_exit(void)
+{
+	acpi_bus_unregister_driver(&acpi_topstar_driver);
+}
+
+module_init(topstar_laptop_init);
+module_exit(topstar_laptop_exit);
+
+MODULE_AUTHOR("Herton Ronaldo Krzesinski");
+MODULE_DESCRIPTION("Topstar Laptop ACPI Extras driver");
+MODULE_LICENSE("GPL");