diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index e4f599f..f7ef828 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -236,6 +236,13 @@ config LEDS_BD2802
 	  This option enables support for BD2802GU RGB LED driver chips
 	  accessed via the I2C bus.
 
+config LEDS_DELL_NETBOOKS
+	tristate "External LED on Dell Business Netbooks"
+	depends on LEDS_CLASS && X86 && ACPI_WMI
+	help
+	  This adds support for the Latitude 2100 and similar
+	  notebooks that have an external LED.
+
 comment "LED Triggers"
 
 config LEDS_TRIGGERS
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 46d7270..a66f328 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_LEDS_DA903X)		+= leds-da903x.o
 obj-$(CONFIG_LEDS_WM831X_STATUS)	+= leds-wm831x-status.o
 obj-$(CONFIG_LEDS_WM8350)		+= leds-wm8350.o
 obj-$(CONFIG_LEDS_PWM)			+= leds-pwm.o
+obj-$(CONFIG_LEDS_DELL_NETBOOKS)	+= dell-led.o
 
 # LED SPI Drivers
 obj-$(CONFIG_LEDS_DAC124S085)		+= leds-dac124s085.o
diff --git a/drivers/leds/dell-led.c b/drivers/leds/dell-led.c
new file mode 100644
index 0000000..ee31089
--- /dev/null
+++ b/drivers/leds/dell-led.c
@@ -0,0 +1,200 @@
+/*
+ * dell_led.c - Dell LED Driver
+ *
+ * Copyright (C) 2010 Dell Inc.
+ * Louis Davis <louis_davis@dell.com>
+ * Jim Dailey <jim_dailey@dell.com>
+ *
+ * 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.
+ *
+ */
+
+#include <linux/acpi.h>
+#include <linux/leds.h>
+
+MODULE_AUTHOR("Louis Davis/Jim Dailey");
+MODULE_DESCRIPTION("Dell LED Control Driver");
+MODULE_LICENSE("GPL");
+
+#define DELL_LED_BIOS_GUID "F6E4FE6E-909D-47cb-8BAB-C9F6F2F8D396"
+MODULE_ALIAS("wmi:" DELL_LED_BIOS_GUID);
+
+/* Error Result Codes: */
+#define INVALID_DEVICE_ID	250
+#define INVALID_PARAMETER	251
+#define INVALID_BUFFER		252
+#define INTERFACE_ERROR		253
+#define UNSUPPORTED_COMMAND	254
+#define UNSPECIFIED_ERROR	255
+
+/* Device ID */
+#define DEVICE_ID_PANEL_BACK	1
+
+/* LED Commands */
+#define CMD_LED_ON	16
+#define CMD_LED_OFF	17
+#define CMD_LED_BLINK	18
+
+struct bios_args {
+	unsigned char length;
+	unsigned char result_code;
+	unsigned char device_id;
+	unsigned char command;
+	unsigned char on_time;
+	unsigned char off_time;
+};
+
+static int dell_led_perform_fn(u8 length,
+		u8 result_code,
+		u8 device_id,
+		u8 command,
+		u8 on_time,
+		u8 off_time)
+{
+	struct bios_args *bios_return;
+	u8 return_code;
+	union acpi_object *obj;
+	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+	struct acpi_buffer input;
+	acpi_status status;
+
+	struct bios_args args;
+	args.length = length;
+	args.result_code = result_code;
+	args.device_id = device_id;
+	args.command = command;
+	args.on_time = on_time;
+	args.off_time = off_time;
+
+	input.length = sizeof(struct bios_args);
+	input.pointer = &args;
+
+	status = wmi_evaluate_method(DELL_LED_BIOS_GUID,
+		1,
+		1,
+		&input,
+		&output);
+
+	if (ACPI_FAILURE(status))
+		return status;
+
+	obj = output.pointer;
+
+	if (!obj)
+		return -EINVAL;
+	else if (obj->type != ACPI_TYPE_BUFFER) {
+		kfree(obj);
+		return -EINVAL;
+	}
+
+	bios_return = ((struct bios_args *)obj->buffer.pointer);
+	return_code = bios_return->result_code;
+
+	kfree(obj);
+
+	return return_code;
+}
+
+static int led_on(void)
+{
+	return dell_led_perform_fn(3,	/* Length of command */
+		INTERFACE_ERROR,	/* Init to  INTERFACE_ERROR */
+		DEVICE_ID_PANEL_BACK,	/* Device ID */
+		CMD_LED_ON,		/* Command */
+		0,			/* not used */
+		0);			/* not used */
+}
+
+static int led_off(void)
+{
+	return dell_led_perform_fn(3,	/* Length of command */
+		INTERFACE_ERROR,	/* Init to  INTERFACE_ERROR */
+		DEVICE_ID_PANEL_BACK,	/* Device ID */
+		CMD_LED_OFF,		/* Command */
+		0,			/* not used */
+		0);			/* not used */
+}
+
+static int led_blink(unsigned char on_eighths,
+		unsigned char off_eighths)
+{
+	return dell_led_perform_fn(5,	/* Length of command */
+		INTERFACE_ERROR,	/* Init to  INTERFACE_ERROR */
+		DEVICE_ID_PANEL_BACK,	/* Device ID */
+		CMD_LED_BLINK,		/* Command */
+		on_eighths,		/* blink on in eigths of a second */
+		off_eighths);		/* blink off in eights of a second */
+}
+
+static void dell_led_set(struct led_classdev *led_cdev,
+		enum led_brightness value)
+{
+	if (value == LED_OFF)
+		led_off();
+	else
+		led_on();
+}
+
+static int dell_led_blink(struct led_classdev *led_cdev,
+		unsigned long *delay_on,
+		unsigned long *delay_off)
+{
+	unsigned long on_eighths;
+	unsigned long off_eighths;
+
+	/* The Dell LED delay is based on 125ms intervals.
+	   Need to round up to next interval. */
+
+	on_eighths = (*delay_on + 124) / 125;
+	if (0 == on_eighths)
+		on_eighths = 1;
+	if (on_eighths > 255)
+		on_eighths = 255;
+	*delay_on = on_eighths * 125;
+
+	off_eighths = (*delay_off + 124) / 125;
+	if (0 == off_eighths)
+		off_eighths = 1;
+	if (off_eighths > 255)
+		off_eighths = 255;
+	*delay_off = off_eighths * 125;
+
+	led_blink(on_eighths, off_eighths);
+
+	return 0;
+}
+
+static struct led_classdev dell_led = {
+	.name		= "dell::lid",
+	.brightness	= LED_OFF,
+	.max_brightness = 1,
+	.brightness_set = dell_led_set,
+	.blink_set	= dell_led_blink,
+	.flags		= LED_CORE_SUSPENDRESUME,
+};
+
+static int __init dell_led_init(void)
+{
+	int error = 0;
+
+	if (!wmi_has_guid(DELL_LED_BIOS_GUID))
+		return -ENODEV;
+
+	error = led_off();
+	if (error != 0)
+		return -ENODEV;
+
+	return led_classdev_register(NULL, &dell_led);
+}
+
+static void __exit dell_led_exit(void)
+{
+	led_classdev_unregister(&dell_led);
+
+	led_off();
+}
+
+module_init(dell_led_init);
+module_exit(dell_led_exit);
-- 
1.6.2.4


From 66bb12c7c267bcf555773dc5162aecd859f2d23b Mon Sep 17 00:00:00 2001
From: Tim Gardner <tim.gardner@canonical.com>
Date: Mon, 22 Feb 2010 08:08:41 -0700
Subject: [PATCH 2/2] UBUNTU: [Config] Enabled CONFIG_LEDS_DELL_NETBOOKS=m

Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
---
 debian.master/config/config.common.ubuntu |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/debian.master/config/config.common.ubuntu b/debian.master/config/config.common.ubuntu
index b63c87f..0098921 100644
--- a/debian.master/config/config.common.ubuntu
+++ b/debian.master/config/config.common.ubuntu
@@ -1998,6 +1998,7 @@ CONFIG_LEDS_CLASS=m
 CONFIG_LEDS_CPU=y
 CONFIG_LEDS_DA903X=m
 CONFIG_LEDS_DAC124S085=m
+CONFIG_LEDS_DELL_NETBOOKS=m
 CONFIG_LEDS_GPIO=m
 CONFIG_LEDS_GPIO_PLATFORM=y
 CONFIG_LEDS_LP3944=m
