drivers/platform/x86/dell-laptop.c - kernel/msm-5.4 - Gitiles

 /*
  *  Driver for Dell laptop extras
  *
  *  Copyright (c) Red Hat <mjg@redhat.com>
  *
  *  Based on documentation in the libsmbios package, Copyright (C) 2005 Dell
  *  Inc.
  *
  *  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/module.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>
 #include <linux/backlight.h>
 #include <linux/err.h>
 #include <linux/dmi.h>
 #include <linux/io.h>
 #include <linux/rfkill.h>
 #include <linux/power_supply.h>
 #include <linux/acpi.h>
 #include <linux/mm.h>
 #include <linux/i8042.h>
 #include <linux/slab.h>
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
 #include "../../firmware/dcdbas.h"

 #define BRIGHTNESS_TOKEN 0x7d

 /* This structure will be modified by the firmware when we enter
  * system management mode, hence the volatiles */

 struct calling_interface_buffer {
 	u16 class;
 	u16 select;
 	volatile u32 input[4];
 	volatile u32 output[4];
 } __packed;

 struct calling_interface_token {
 	u16 tokenID;
 	u16 location;
 	union {
 		u16 value;
 		u16 stringlength;
 	};
 };

 struct calling_interface_structure {
 	struct dmi_header header;
 	u16 cmdIOAddress;
 	u8 cmdIOCode;
 	u32 supportedCmds;
 	struct calling_interface_token tokens[];
 } __packed;

 struct quirk_entry {
 	u8 touchpad_led;
 };

 static struct quirk_entry *quirks;

 static struct quirk_entry quirk_dell_vostro_v130 = {
 	.touchpad_led = 1,
 };

 static int dmi_matched(const struct dmi_system_id *dmi)
 {
 	quirks = dmi->driver_data;
 	return 1;
 }

 static int da_command_address;
 static int da_command_code;
 static int da_num_tokens;
 static struct calling_interface_token *da_tokens;

 static struct platform_driver platform_driver = {
 	.driver = {
 		.name = "dell-laptop",
 		.owner = THIS_MODULE,
 	}
 };

 static struct platform_device *platform_device;
 static struct backlight_device *dell_backlight_device;
 static struct rfkill *wifi_rfkill;
 static struct rfkill *bluetooth_rfkill;
 static struct rfkill *wwan_rfkill;

 static const struct dmi_system_id __initdata dell_device_table[] = {
 	{
 		.ident = "Dell laptop",
 		.matches = {
 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 			DMI_MATCH(DMI_CHASSIS_TYPE, "8"),
 		},
 	},
 	{
 		.matches = {
 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 			DMI_MATCH(DMI_CHASSIS_TYPE, "9"), /*Laptop*/
 		},
 	},
 	{
 		.ident = "Dell Computer Corporation",
 		.matches = {
 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
 			DMI_MATCH(DMI_CHASSIS_TYPE, "8"),
 		},
 	},
 	{ }
 };
 MODULE_DEVICE_TABLE(dmi, dell_device_table);

 static struct dmi_system_id __devinitdata dell_blacklist[] = {
 	/* Supported by compal-laptop */
 	{
 		.ident = "Dell Mini 9",
 		.matches = {
 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 910"),
 		},
 	},
 	{
 		.ident = "Dell Mini 10",
 		.matches = {
 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 1010"),
 		},
 	},
 	{
 		.ident = "Dell Mini 10v",
 		.matches = {
 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 1011"),
 		},
 	},
 	{
 		.ident = "Dell Mini 1012",
 		.matches = {
 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 1012"),
 		},
 	},
 	{
 		.ident = "Dell Inspiron 11z",
 		.matches = {
 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 1110"),
 		},
 	},
 	{
 		.ident = "Dell Mini 12",
 		.matches = {
 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 1210"),
 		},
 	},
 	{}
 };

 static struct dmi_system_id __devinitdata dell_quirks[] = {
 	{
 		.callback = dmi_matched,
 		.ident = "Dell Vostro V130",
 		.matches = {
 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 			DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V130"),
 		},
 		.driver_data = &quirk_dell_vostro_v130,
 	},
 	{
 		.callback = dmi_matched,
 		.ident = "Dell Vostro V131",
 		.matches = {
 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 			DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
 		},
 		.driver_data = &quirk_dell_vostro_v130,
 	},
 	{
 		.callback = dmi_matched,
 		.ident = "Dell Vostro 3555",
 		.matches = {
 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 			DMI_MATCH(DMI_PRODUCT_NAME, "Vostro 3555"),
 		},
 		.driver_data = &quirk_dell_vostro_v130,
 	},
 	{
 		.callback = dmi_matched,
 		.ident = "Dell Inspiron N311z",
 		.matches = {
 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron N311z"),
 		},
 		.driver_data = &quirk_dell_vostro_v130,
 	},
 	{
 		.callback = dmi_matched,
 		.ident = "Dell Inspiron M5110",
 		.matches = {
 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron M5110"),
 		},
 		.driver_data = &quirk_dell_vostro_v130,
 	},
 	{ }
 };

 static struct calling_interface_buffer *buffer;
 static struct page *bufferpage;
 static DEFINE_MUTEX(buffer_mutex);

 static int hwswitch_state;

 static void get_buffer(void)
 {
 	mutex_lock(&buffer_mutex);
 	memset(buffer, 0, sizeof(struct calling_interface_buffer));
 }

 static void release_buffer(void)
 {
 	mutex_unlock(&buffer_mutex);
 }

 static void __init parse_da_table(const struct dmi_header *dm)
 {
 	/* Final token is a terminator, so we don't want to copy it */
 	int tokens = (dm->length-11)/sizeof(struct calling_interface_token)-1;
 	struct calling_interface_structure *table =
 		container_of(dm, struct calling_interface_structure, header);

 	/* 4 bytes of table header, plus 7 bytes of Dell header, plus at least
 	   6 bytes of entry */

 	if (dm->length < 17)
 		return;

 	da_command_address = table->cmdIOAddress;
 	da_command_code = table->cmdIOCode;

 	da_tokens = krealloc(da_tokens, (da_num_tokens + tokens) *
 			     sizeof(struct calling_interface_token),
 			     GFP_KERNEL);

 	if (!da_tokens)
 		return;

 	memcpy(da_tokens+da_num_tokens, table->tokens,
 	       sizeof(struct calling_interface_token) * tokens);

 	da_num_tokens += tokens;
 }

 static void __init find_tokens(const struct dmi_header *dm, void *dummy)
 {
 	switch (dm->type) {
 	case 0xd4: /* Indexed IO */
 	case 0xd5: /* Protected Area Type 1 */
 	case 0xd6: /* Protected Area Type 2 */
 		break;
 	case 0xda: /* Calling interface */
 		parse_da_table(dm);
 		break;
 	}
 }

 static int find_token_location(int tokenid)
 {
 	int i;
 	for (i = 0; i < da_num_tokens; i++) {
 		if (da_tokens[i].tokenID == tokenid)
 			return da_tokens[i].location;
 	}

 	return -1;
 }

 static struct calling_interface_buffer *
 dell_send_request(struct calling_interface_buffer *buffer, int class,
 		  int select)
 {
 	struct smi_cmd command;

 	command.magic = SMI_CMD_MAGIC;
 	command.command_address = da_command_address;
 	command.command_code = da_command_code;
 	command.ebx = virt_to_phys(buffer);
 	command.ecx = 0x42534931;

 	buffer->class = class;
 	buffer->select = select;

 	dcdbas_smi_request(&command);

 	return buffer;
 }

 /* Derived from information in DellWirelessCtl.cpp:
    Class 17, select 11 is radio control. It returns an array of 32-bit values.

    Input byte 0 = 0: Wireless information

    result[0]: return code
    result[1]:
      Bit 0:      Hardware switch supported
      Bit 1:      Wifi locator supported
      Bit 2:      Wifi is supported
      Bit 3:      Bluetooth is supported
      Bit 4:      WWAN is supported
      Bit 5:      Wireless keyboard supported
      Bits 6-7:   Reserved
      Bit 8:      Wifi is installed
      Bit 9:      Bluetooth is installed
      Bit 10:     WWAN is installed
      Bits 11-15: Reserved
      Bit 16:     Hardware switch is on
      Bit 17:     Wifi is blocked
      Bit 18:     Bluetooth is blocked
      Bit 19:     WWAN is blocked
      Bits 20-31: Reserved
    result[2]: NVRAM size in bytes
    result[3]: NVRAM format version number

    Input byte 0 = 2: Wireless switch configuration
    result[0]: return code
    result[1]:
      Bit 0:      Wifi controlled by switch
      Bit 1:      Bluetooth controlled by switch
      Bit 2:      WWAN controlled by switch
      Bits 3-6:   Reserved
      Bit 7:      Wireless switch config locked
      Bit 8:      Wifi locator enabled
      Bits 9-14:  Reserved
      Bit 15:     Wifi locator setting locked
      Bits 16-31: Reserved
 */

 static int dell_rfkill_set(void *data, bool blocked)
 {
 	int disable = blocked ? 1 : 0;
 	unsigned long radio = (unsigned long)data;
 	int hwswitch_bit = (unsigned long)data - 1;
 	int ret = 0;

 	get_buffer();
 	dell_send_request(buffer, 17, 11);

 	/* If the hardware switch controls this radio, and the hardware
 	   switch is disabled, don't allow changing the software state */
 	if ((hwswitch_state & BIT(hwswitch_bit)) &&
 	    !(buffer->output[1] & BIT(16))) {
 		ret = -EINVAL;
 		goto out;
 	}

 	buffer->input[0] = (1 | (radio<<8) | (disable << 16));
 	dell_send_request(buffer, 17, 11);

 out:
 	release_buffer();
 	return ret;
 }

 static void dell_rfkill_query(struct rfkill *rfkill, void *data)
 {
 	int status;
 	int bit = (unsigned long)data + 16;
 	int hwswitch_bit = (unsigned long)data - 1;

 	get_buffer();
 	dell_send_request(buffer, 17, 11);
 	status = buffer->output[1];
 	release_buffer();

 	rfkill_set_sw_state(rfkill, !!(status & BIT(bit)));

 	if (hwswitch_state & (BIT(hwswitch_bit)))
 		rfkill_set_hw_state(rfkill, !(status & BIT(16)));
 }

 static const struct rfkill_ops dell_rfkill_ops = {
 	.set_block = dell_rfkill_set,
 	.query = dell_rfkill_query,
 };

 static struct dentry *dell_laptop_dir;

 static int dell_debugfs_show(struct seq_file *s, void *data)
 {
 	int status;

 	get_buffer();
 	dell_send_request(buffer, 17, 11);
 	status = buffer->output[1];
 	release_buffer();

 	seq_printf(s, "status:\t0x%X\n", status);
 	seq_printf(s, "Bit 0 : Hardware switch supported:   %lu\n",
 		   status & BIT(0));
 	seq_printf(s, "Bit 1 : Wifi locator supported:      %lu\n",
 		  (status & BIT(1)) >> 1);
 	seq_printf(s, "Bit 2 : Wifi is supported:           %lu\n",
 		  (status & BIT(2)) >> 2);
 	seq_printf(s, "Bit 3 : Bluetooth is supported:      %lu\n",
 		  (status & BIT(3)) >> 3);
 	seq_printf(s, "Bit 4 : WWAN is supported:           %lu\n",
 		  (status & BIT(4)) >> 4);
 	seq_printf(s, "Bit 5 : Wireless keyboard supported: %lu\n",
 		  (status & BIT(5)) >> 5);
 	seq_printf(s, "Bit 8 : Wifi is installed:           %lu\n",
 		  (status & BIT(8)) >> 8);
 	seq_printf(s, "Bit 9 : Bluetooth is installed:      %lu\n",
 		  (status & BIT(9)) >> 9);
 	seq_printf(s, "Bit 10: WWAN is installed:           %lu\n",
 		  (status & BIT(10)) >> 10);
 	seq_printf(s, "Bit 16: Hardware switch is on:       %lu\n",
 		  (status & BIT(16)) >> 16);
 	seq_printf(s, "Bit 17: Wifi is blocked:             %lu\n",
 		  (status & BIT(17)) >> 17);
 	seq_printf(s, "Bit 18: Bluetooth is blocked:        %lu\n",
 		  (status & BIT(18)) >> 18);
 	seq_printf(s, "Bit 19: WWAN is blocked:             %lu\n",
 		  (status & BIT(19)) >> 19);

 	seq_printf(s, "\nhwswitch_state:\t0x%X\n", hwswitch_state);
 	seq_printf(s, "Bit 0 : Wifi controlled by switch:      %lu\n",
 		   hwswitch_state & BIT(0));
 	seq_printf(s, "Bit 1 : Bluetooth controlled by switch: %lu\n",
 		   (hwswitch_state & BIT(1)) >> 1);
 	seq_printf(s, "Bit 2 : WWAN controlled by switch:      %lu\n",
 		   (hwswitch_state & BIT(2)) >> 2);
 	seq_printf(s, "Bit 7 : Wireless switch config locked:  %lu\n",
 		   (hwswitch_state & BIT(7)) >> 7);
 	seq_printf(s, "Bit 8 : Wifi locator enabled:           %lu\n",
 		   (hwswitch_state & BIT(8)) >> 8);
 	seq_printf(s, "Bit 15: Wifi locator setting locked:    %lu\n",
 		   (hwswitch_state & BIT(15)) >> 15);

 	return 0;
 }

 static int dell_debugfs_open(struct inode *inode, struct file *file)
 {
 	return single_open(file, dell_debugfs_show, inode->i_private);
 }

 static const struct file_operations dell_debugfs_fops = {
 	.owner = THIS_MODULE,
 	.open = dell_debugfs_open,
 	.read = seq_read,
 	.llseek = seq_lseek,
 	.release = single_release,
 };

 static void dell_update_rfkill(struct work_struct *ignored)
 {
 	if (wifi_rfkill)
 		dell_rfkill_query(wifi_rfkill, (void *)1);
 	if (bluetooth_rfkill)
 		dell_rfkill_query(bluetooth_rfkill, (void *)2);
 	if (wwan_rfkill)
 		dell_rfkill_query(wwan_rfkill, (void *)3);
 }
 static DECLARE_DELAYED_WORK(dell_rfkill_work, dell_update_rfkill);


 static int __init dell_setup_rfkill(void)
 {
 	int status;
 	int ret;

 	if (dmi_check_system(dell_blacklist)) {
 		pr_info("Blacklisted hardware detected - not enabling rfkill\n");
 		return 0;
 	}

 	get_buffer();
 	dell_send_request(buffer, 17, 11);
 	status = buffer->output[1];
 	buffer->input[0] = 0x2;
 	dell_send_request(buffer, 17, 11);
 	hwswitch_state = buffer->output[1];
 	release_buffer();

 	if ((status & (1<<2|1<<8)) == (1<<2|1<<8)) {
 		wifi_rfkill = rfkill_alloc("dell-wifi", &platform_device->dev,
 					   RFKILL_TYPE_WLAN,
 					   &dell_rfkill_ops, (void *) 1);
 		if (!wifi_rfkill) {
 			ret = -ENOMEM;
 			goto err_wifi;
 		}
 		ret = rfkill_register(wifi_rfkill);
 		if (ret)
 			goto err_wifi;
 	}

 	if ((status & (1<<3|1<<9)) == (1<<3|1<<9)) {
 		bluetooth_rfkill = rfkill_alloc("dell-bluetooth",
 						&platform_device->dev,
 						RFKILL_TYPE_BLUETOOTH,
 						&dell_rfkill_ops, (void *) 2);
 		if (!bluetooth_rfkill) {
 			ret = -ENOMEM;
 			goto err_bluetooth;
 		}
 		ret = rfkill_register(bluetooth_rfkill);
 		if (ret)
 			goto err_bluetooth;
 	}

 	if ((status & (1<<4|1<<10)) == (1<<4|1<<10)) {
 		wwan_rfkill = rfkill_alloc("dell-wwan",
 					   &platform_device->dev,
 					   RFKILL_TYPE_WWAN,
 					   &dell_rfkill_ops, (void *) 3);
 		if (!wwan_rfkill) {
 			ret = -ENOMEM;
 			goto err_wwan;
 		}
 		ret = rfkill_register(wwan_rfkill);
 		if (ret)
 			goto err_wwan;
 	}

 	return 0;
 err_wwan:
 	rfkill_destroy(wwan_rfkill);
 	if (bluetooth_rfkill)
 		rfkill_unregister(bluetooth_rfkill);
 err_bluetooth:
 	rfkill_destroy(bluetooth_rfkill);
 	if (wifi_rfkill)
 		rfkill_unregister(wifi_rfkill);
 err_wifi:
 	rfkill_destroy(wifi_rfkill);

 	return ret;
 }

 static void dell_cleanup_rfkill(void)
 {
 	if (wifi_rfkill) {
 		rfkill_unregister(wifi_rfkill);
 		rfkill_destroy(wifi_rfkill);
 	}
 	if (bluetooth_rfkill) {
 		rfkill_unregister(bluetooth_rfkill);
 		rfkill_destroy(bluetooth_rfkill);
 	}
 	if (wwan_rfkill) {
 		rfkill_unregister(wwan_rfkill);
 		rfkill_destroy(wwan_rfkill);
 	}
 }

 static int dell_send_intensity(struct backlight_device *bd)
 {
 	int ret = 0;

 	get_buffer();
 	buffer->input[0] = find_token_location(BRIGHTNESS_TOKEN);
 	buffer->input[1] = bd->props.brightness;

 	if (buffer->input[0] == -1) {
 		ret = -ENODEV;
 		goto out;
 	}

 	if (power_supply_is_system_supplied() > 0)
 		dell_send_request(buffer, 1, 2);
 	else
 		dell_send_request(buffer, 1, 1);

 out:
 	release_buffer();
 	return 0;
 }

 static int dell_get_intensity(struct backlight_device *bd)
 {
 	int ret = 0;

 	get_buffer();
 	buffer->input[0] = find_token_location(BRIGHTNESS_TOKEN);

 	if (buffer->input[0] == -1) {
 		ret = -ENODEV;
 		goto out;
 	}

 	if (power_supply_is_system_supplied() > 0)
 		dell_send_request(buffer, 0, 2);
 	else
 		dell_send_request(buffer, 0, 1);

 	ret = buffer->output[1];

 out:
 	release_buffer();
 	return ret;
 }

 static const struct backlight_ops dell_ops = {
 	.get_brightness = dell_get_intensity,
 	.update_status  = dell_send_intensity,
 };

 static void touchpad_led_on(void)
 {
 	int command = 0x97;
 	char data = 1;
 	i8042_command(&data, command | 1 << 12);
 }

 static void touchpad_led_off(void)
 {
 	int command = 0x97;
 	char data = 2;
 	i8042_command(&data, command | 1 << 12);
 }

 static void touchpad_led_set(struct led_classdev *led_cdev,
 	enum led_brightness value)
 {
 	if (value > 0)
 		touchpad_led_on();
 	else
 		touchpad_led_off();
 }

 static struct led_classdev touchpad_led = {
 	.name = "dell-laptop::touchpad",
 	.brightness_set = touchpad_led_set,
 	.flags = LED_CORE_SUSPENDRESUME,
 };

 static int __devinit touchpad_led_init(struct device *dev)
 {
 	return led_classdev_register(dev, &touchpad_led);
 }

 static void touchpad_led_exit(void)
 {
 	led_classdev_unregister(&touchpad_led);
 }

 static bool dell_laptop_i8042_filter(unsigned char data, unsigned char str,
 			      struct serio *port)
 {
 	static bool extended;

 	if (str & 0x20)
 		return false;

 	if (unlikely(data == 0xe0)) {
 		extended = true;
 		return false;
 	} else if (unlikely(extended)) {
 		switch (data) {
 		case 0x8:
 			schedule_delayed_work(&dell_rfkill_work,
 					      round_jiffies_relative(HZ));
 			break;
 		}
 		extended = false;
 	}

 	return false;
 }

 static int __init dell_init(void)
 {
 	int max_intensity = 0;
 	int ret;

 	if (!dmi_check_system(dell_device_table))
 		return -ENODEV;

 	quirks = NULL;
 	/* find if this machine support other functions */
 	dmi_check_system(dell_quirks);

 	dmi_walk(find_tokens, NULL);

 	if (!da_tokens)  {
 		pr_info("Unable to find dmi tokens\n");
 		return -ENODEV;
 	}

 	ret = platform_driver_register(&platform_driver);
 	if (ret)
 		goto fail_platform_driver;
 	platform_device = platform_device_alloc("dell-laptop", -1);
 	if (!platform_device) {
 		ret = -ENOMEM;
 		goto fail_platform_device1;
 	}
 	ret = platform_device_add(platform_device);
 	if (ret)
 		goto fail_platform_device2;

 	/*
 	 * Allocate buffer below 4GB for SMI data--only 32-bit physical addr
 	 * is passed to SMI handler.
 	 */
 	bufferpage = alloc_page(GFP_KERNEL | GFP_DMA32);

 	if (!bufferpage)
 		goto fail_buffer;
 	buffer = page_address(bufferpage);

 	ret = dell_setup_rfkill();

 	if (ret) {
 		pr_warn("Unable to setup rfkill\n");
 		goto fail_rfkill;
 	}

 	ret = i8042_install_filter(dell_laptop_i8042_filter);
 	if (ret) {
 		pr_warn("Unable to install key filter\n");
 		goto fail_filter;
 	}

 	if (quirks && quirks->touchpad_led)
 		touchpad_led_init(&platform_device->dev);

 	dell_laptop_dir = debugfs_create_dir("dell_laptop", NULL);
 	if (dell_laptop_dir != NULL)
 		debugfs_create_file("rfkill", 0444, dell_laptop_dir, NULL,
 				    &dell_debugfs_fops);

 #ifdef CONFIG_ACPI
 	/* In the event of an ACPI backlight being available, don't
 	 * register the platform controller.
 	 */
 	if (acpi_video_backlight_support())
 		return 0;
 #endif

 	get_buffer();
 	buffer->input[0] = find_token_location(BRIGHTNESS_TOKEN);
 	if (buffer->input[0] != -1) {
 		dell_send_request(buffer, 0, 2);
 		max_intensity = buffer->output[3];
 	}
 	release_buffer();

 	if (max_intensity) {
 		struct backlight_properties props;
 		memset(&props, 0, sizeof(struct backlight_properties));
 		props.type = BACKLIGHT_PLATFORM;
 		props.max_brightness = max_intensity;
 		dell_backlight_device = backlight_device_register("dell_backlight",
 								  &platform_device->dev,
 								  NULL,
 								  &dell_ops,
 								  &props);

 		if (IS_ERR(dell_backlight_device)) {
 			ret = PTR_ERR(dell_backlight_device);
 			dell_backlight_device = NULL;
 			goto fail_backlight;
 		}

 		dell_backlight_device->props.brightness =
 			dell_get_intensity(dell_backlight_device);
 		backlight_update_status(dell_backlight_device);
 	}

 	return 0;

 fail_backlight:
 	i8042_remove_filter(dell_laptop_i8042_filter);
 	cancel_delayed_work_sync(&dell_rfkill_work);
 fail_filter:
 	dell_cleanup_rfkill();
 fail_rfkill:
 	free_page((unsigned long)bufferpage);
 fail_buffer:
 	platform_device_del(platform_device);
 fail_platform_device2:
 	platform_device_put(platform_device);
 fail_platform_device1:
 	platform_driver_unregister(&platform_driver);
 fail_platform_driver:
 	kfree(da_tokens);
 	return ret;
 }

 static void __exit dell_exit(void)
 {
 	debugfs_remove_recursive(dell_laptop_dir);
 	if (quirks && quirks->touchpad_led)
 		touchpad_led_exit();
 	i8042_remove_filter(dell_laptop_i8042_filter);
 	cancel_delayed_work_sync(&dell_rfkill_work);
 	backlight_device_unregister(dell_backlight_device);
 	dell_cleanup_rfkill();
 	if (platform_device) {
 		platform_device_unregister(platform_device);
 		platform_driver_unregister(&platform_driver);
 	}
 	kfree(da_tokens);
 	free_page((unsigned long)buffer);
 }

 module_init(dell_init);
 module_exit(dell_exit);

 MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
 MODULE_DESCRIPTION("Dell laptop driver");
 MODULE_LICENSE("GPL");
	/*
	* Driver for Dell laptop extras
	*
	* Copyright (c) Red Hat <mjg@redhat.com>
	*
	* Based on documentation in the libsmbios package, Copyright (C) 2005 Dell
	* Inc.
	*
	* 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/module.h>
	#include <linux/kernel.h>
	#include <linux/init.h>
	#include <linux/platform_device.h>
	#include <linux/backlight.h>
	#include <linux/err.h>
	#include <linux/dmi.h>
	#include <linux/io.h>
	#include <linux/rfkill.h>
	#include <linux/power_supply.h>
	#include <linux/acpi.h>
	#include <linux/mm.h>
	#include <linux/i8042.h>
	#include <linux/slab.h>
	#include <linux/debugfs.h>
	#include <linux/seq_file.h>
	#include "../../firmware/dcdbas.h"

	#define BRIGHTNESS_TOKEN 0x7d

	/* This structure will be modified by the firmware when we enter
	* system management mode, hence the volatiles */

	struct calling_interface_buffer {
	u16 class;
	u16 select;
	volatile u32 input[4];
	volatile u32 output[4];
	} __packed;

	struct calling_interface_token {
	u16 tokenID;
	u16 location;
	union {
	u16 value;
	u16 stringlength;
	};
	};

	struct calling_interface_structure {
	struct dmi_header header;
	u16 cmdIOAddress;
	u8 cmdIOCode;
	u32 supportedCmds;
	struct calling_interface_token tokens[];
	} __packed;

	struct quirk_entry {
	u8 touchpad_led;
	};

	static struct quirk_entry *quirks;

	static struct quirk_entry quirk_dell_vostro_v130 = {
	.touchpad_led = 1,
	};

	static int dmi_matched(const struct dmi_system_id *dmi)
	{
	quirks = dmi->driver_data;
	return 1;
	}

	static int da_command_address;
	static int da_command_code;
	static int da_num_tokens;
	static struct calling_interface_token *da_tokens;

	static struct platform_driver platform_driver = {
	.driver = {
	.name = "dell-laptop",
	.owner = THIS_MODULE,
	}
	};

	static struct platform_device *platform_device;
	static struct backlight_device *dell_backlight_device;
	static struct rfkill *wifi_rfkill;
	static struct rfkill *bluetooth_rfkill;
	static struct rfkill *wwan_rfkill;

	static const struct dmi_system_id __initdata dell_device_table[] = {
	{
	.ident = "Dell laptop",
	.matches = {
	DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
	DMI_MATCH(DMI_CHASSIS_TYPE, "8"),
	},
	},
	{
	.matches = {
	DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
	DMI_MATCH(DMI_CHASSIS_TYPE, "9"), /Laptop/
	},
	},
	{
	.ident = "Dell Computer Corporation",
	.matches = {
	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
	DMI_MATCH(DMI_CHASSIS_TYPE, "8"),
	},
	},
	{ }
	};
	MODULE_DEVICE_TABLE(dmi, dell_device_table);

	static struct dmi_system_id __devinitdata dell_blacklist[] = {
	/* Supported by compal-laptop */
	{
	.ident = "Dell Mini 9",
	.matches = {
	DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
	DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 910"),
	},
	},
	{
	.ident = "Dell Mini 10",
	.matches = {
	DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
	DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 1010"),
	},
	},
	{
	.ident = "Dell Mini 10v",
	.matches = {
	DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
	DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 1011"),
	},
	},
	{
	.ident = "Dell Mini 1012",
	.matches = {
	DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
	DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 1012"),
	},
	},
	{
	.ident = "Dell Inspiron 11z",
	.matches = {
	DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
	DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 1110"),
	},
	},
	{
	.ident = "Dell Mini 12",
	.matches = {
	DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
	DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 1210"),
	},
	},
	{}
	};

	static struct dmi_system_id __devinitdata dell_quirks[] = {
	{
	.callback = dmi_matched,
	.ident = "Dell Vostro V130",
	.matches = {
	DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
	DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V130"),
	},
	.driver_data = &quirk_dell_vostro_v130,
	},
	{
	.callback = dmi_matched,
	.ident = "Dell Vostro V131",
	.matches = {
	DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
	DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
	},
	.driver_data = &quirk_dell_vostro_v130,
	},
	{
	.callback = dmi_matched,
	.ident = "Dell Vostro 3555",
	.matches = {
	DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
	DMI_MATCH(DMI_PRODUCT_NAME, "Vostro 3555"),
	},
	.driver_data = &quirk_dell_vostro_v130,
	},
	{
	.callback = dmi_matched,
	.ident = "Dell Inspiron N311z",
	.matches = {
	DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
	DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron N311z"),
	},
	.driver_data = &quirk_dell_vostro_v130,
	},
	{
	.callback = dmi_matched,
	.ident = "Dell Inspiron M5110",
	.matches = {
	DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
	DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron M5110"),
	},
	.driver_data = &quirk_dell_vostro_v130,
	},
	{ }
	};

	static struct calling_interface_buffer *buffer;
	static struct page *bufferpage;
	static DEFINE_MUTEX(buffer_mutex);

	static int hwswitch_state;

	static void get_buffer(void)
	{
	mutex_lock(&buffer_mutex);
	memset(buffer, 0, sizeof(struct calling_interface_buffer));
	}

	static void release_buffer(void)
	{
	mutex_unlock(&buffer_mutex);
	}

	static void __init parse_da_table(const struct dmi_header *dm)
	{
	/* Final token is a terminator, so we don't want to copy it */
	int tokens = (dm->length-11)/sizeof(struct calling_interface_token)-1;
	struct calling_interface_structure *table =
	container_of(dm, struct calling_interface_structure, header);

	/* 4 bytes of table header, plus 7 bytes of Dell header, plus at least
	6 bytes of entry */

	if (dm->length < 17)
	return;

	da_command_address = table->cmdIOAddress;
	da_command_code = table->cmdIOCode;

	da_tokens = krealloc(da_tokens, (da_num_tokens + tokens) *
	sizeof(struct calling_interface_token),
	GFP_KERNEL);

	if (!da_tokens)
	return;

	memcpy(da_tokens+da_num_tokens, table->tokens,
	sizeof(struct calling_interface_token) * tokens);

	da_num_tokens += tokens;
	}

	static void __init find_tokens(const struct dmi_header dm, void dummy)
	{
	switch (dm->type) {
	case 0xd4: /* Indexed IO */
	case 0xd5: /* Protected Area Type 1 */
	case 0xd6: /* Protected Area Type 2 */
	break;
	case 0xda: /* Calling interface */
	parse_da_table(dm);
	break;
	}
	}

	static int find_token_location(int tokenid)
	{
	int i;
	for (i = 0; i < da_num_tokens; i++) {
	if (da_tokens[i].tokenID == tokenid)
	return da_tokens[i].location;
	}

	return -1;
	}

	static struct calling_interface_buffer *
	dell_send_request(struct calling_interface_buffer *buffer, int class,
	int select)
	{
	struct smi_cmd command;

	command.magic = SMI_CMD_MAGIC;
	command.command_address = da_command_address;
	command.command_code = da_command_code;
	command.ebx = virt_to_phys(buffer);
	command.ecx = 0x42534931;

	buffer->class = class;
	buffer->select = select;

	dcdbas_smi_request(&command);

	return buffer;
	}

	/* Derived from information in DellWirelessCtl.cpp:
	Class 17, select 11 is radio control. It returns an array of 32-bit values.

	Input byte 0 = 0: Wireless information

	result[0]: return code
	result[1]:
	Bit 0: Hardware switch supported
	Bit 1: Wifi locator supported
	Bit 2: Wifi is supported
	Bit 3: Bluetooth is supported
	Bit 4: WWAN is supported
	Bit 5: Wireless keyboard supported
	Bits 6-7: Reserved
	Bit 8: Wifi is installed
	Bit 9: Bluetooth is installed
	Bit 10: WWAN is installed
	Bits 11-15: Reserved
	Bit 16: Hardware switch is on
	Bit 17: Wifi is blocked
	Bit 18: Bluetooth is blocked
	Bit 19: WWAN is blocked
	Bits 20-31: Reserved
	result[2]: NVRAM size in bytes
	result[3]: NVRAM format version number

	Input byte 0 = 2: Wireless switch configuration
	result[0]: return code
	result[1]:
	Bit 0: Wifi controlled by switch
	Bit 1: Bluetooth controlled by switch
	Bit 2: WWAN controlled by switch
	Bits 3-6: Reserved
	Bit 7: Wireless switch config locked
	Bit 8: Wifi locator enabled
	Bits 9-14: Reserved
	Bit 15: Wifi locator setting locked
	Bits 16-31: Reserved
	*/

	static int dell_rfkill_set(void *data, bool blocked)
	{
	int disable = blocked ? 1 : 0;
	unsigned long radio = (unsigned long)data;
	int hwswitch_bit = (unsigned long)data - 1;
	int ret = 0;

	get_buffer();
	dell_send_request(buffer, 17, 11);

	/* If the hardware switch controls this radio, and the hardware
	switch is disabled, don't allow changing the software state */
	if ((hwswitch_state & BIT(hwswitch_bit)) &&
	!(buffer->output[1] & BIT(16))) {
	ret = -EINVAL;
	goto out;
	}

	buffer->input[0] = (1 \| (radio<<8) \| (disable << 16));
	dell_send_request(buffer, 17, 11);

	out:
	release_buffer();
	return ret;
	}

	static void dell_rfkill_query(struct rfkill rfkill, void data)
	{
	int status;
	int bit = (unsigned long)data + 16;
	int hwswitch_bit = (unsigned long)data - 1;

	get_buffer();
	dell_send_request(buffer, 17, 11);
	status = buffer->output[1];
	release_buffer();

	rfkill_set_sw_state(rfkill, !!(status & BIT(bit)));

	if (hwswitch_state & (BIT(hwswitch_bit)))
	rfkill_set_hw_state(rfkill, !(status & BIT(16)));
	}

	static const struct rfkill_ops dell_rfkill_ops = {
	.set_block = dell_rfkill_set,
	.query = dell_rfkill_query,
	};

	static struct dentry *dell_laptop_dir;

	static int dell_debugfs_show(struct seq_file s, void data)
	{
	int status;

	get_buffer();
	dell_send_request(buffer, 17, 11);
	status = buffer->output[1];
	release_buffer();

	seq_printf(s, "status:\t0x%X\n", status);
	seq_printf(s, "Bit 0 : Hardware switch supported: %lu\n",
	status & BIT(0));
	seq_printf(s, "Bit 1 : Wifi locator supported: %lu\n",
	(status & BIT(1)) >> 1);
	seq_printf(s, "Bit 2 : Wifi is supported: %lu\n",
	(status & BIT(2)) >> 2);
	seq_printf(s, "Bit 3 : Bluetooth is supported: %lu\n",
	(status & BIT(3)) >> 3);
	seq_printf(s, "Bit 4 : WWAN is supported: %lu\n",
	(status & BIT(4)) >> 4);
	seq_printf(s, "Bit 5 : Wireless keyboard supported: %lu\n",
	(status & BIT(5)) >> 5);
	seq_printf(s, "Bit 8 : Wifi is installed: %lu\n",
	(status & BIT(8)) >> 8);
	seq_printf(s, "Bit 9 : Bluetooth is installed: %lu\n",
	(status & BIT(9)) >> 9);
	seq_printf(s, "Bit 10: WWAN is installed: %lu\n",
	(status & BIT(10)) >> 10);
	seq_printf(s, "Bit 16: Hardware switch is on: %lu\n",
	(status & BIT(16)) >> 16);
	seq_printf(s, "Bit 17: Wifi is blocked: %lu\n",
	(status & BIT(17)) >> 17);
	seq_printf(s, "Bit 18: Bluetooth is blocked: %lu\n",
	(status & BIT(18)) >> 18);
	seq_printf(s, "Bit 19: WWAN is blocked: %lu\n",
	(status & BIT(19)) >> 19);

	seq_printf(s, "\nhwswitch_state:\t0x%X\n", hwswitch_state);
	seq_printf(s, "Bit 0 : Wifi controlled by switch: %lu\n",
	hwswitch_state & BIT(0));
	seq_printf(s, "Bit 1 : Bluetooth controlled by switch: %lu\n",
	(hwswitch_state & BIT(1)) >> 1);
	seq_printf(s, "Bit 2 : WWAN controlled by switch: %lu\n",
	(hwswitch_state & BIT(2)) >> 2);
	seq_printf(s, "Bit 7 : Wireless switch config locked: %lu\n",
	(hwswitch_state & BIT(7)) >> 7);
	seq_printf(s, "Bit 8 : Wifi locator enabled: %lu\n",
	(hwswitch_state & BIT(8)) >> 8);
	seq_printf(s, "Bit 15: Wifi locator setting locked: %lu\n",
	(hwswitch_state & BIT(15)) >> 15);

	return 0;
	}

	static int dell_debugfs_open(struct inode inode, struct file file)
	{
	return single_open(file, dell_debugfs_show, inode->i_private);
	}

	static const struct file_operations dell_debugfs_fops = {
	.owner = THIS_MODULE,
	.open = dell_debugfs_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
	};

	static void dell_update_rfkill(struct work_struct *ignored)
	{
	if (wifi_rfkill)
	dell_rfkill_query(wifi_rfkill, (void *)1);
	if (bluetooth_rfkill)
	dell_rfkill_query(bluetooth_rfkill, (void *)2);
	if (wwan_rfkill)
	dell_rfkill_query(wwan_rfkill, (void *)3);
	}
	static DECLARE_DELAYED_WORK(dell_rfkill_work, dell_update_rfkill);


	static int __init dell_setup_rfkill(void)
	{
	int status;
	int ret;

	if (dmi_check_system(dell_blacklist)) {
	pr_info("Blacklisted hardware detected - not enabling rfkill\n");
	return 0;
	}

	get_buffer();
	dell_send_request(buffer, 17, 11);
	status = buffer->output[1];
	buffer->input[0] = 0x2;
	dell_send_request(buffer, 17, 11);
	hwswitch_state = buffer->output[1];
	release_buffer();

	if ((status & (1<<2\|1<<8)) == (1<<2\|1<<8)) {
	wifi_rfkill = rfkill_alloc("dell-wifi", &platform_device->dev,
	RFKILL_TYPE_WLAN,
	&dell_rfkill_ops, (void *) 1);
	if (!wifi_rfkill) {
	ret = -ENOMEM;
	goto err_wifi;
	}
	ret = rfkill_register(wifi_rfkill);
	if (ret)
	goto err_wifi;
	}

	if ((status & (1<<3\|1<<9)) == (1<<3\|1<<9)) {
	bluetooth_rfkill = rfkill_alloc("dell-bluetooth",
	&platform_device->dev,
	RFKILL_TYPE_BLUETOOTH,
	&dell_rfkill_ops, (void *) 2);
	if (!bluetooth_rfkill) {
	ret = -ENOMEM;
	goto err_bluetooth;
	}
	ret = rfkill_register(bluetooth_rfkill);
	if (ret)
	goto err_bluetooth;
	}

	if ((status & (1<<4\|1<<10)) == (1<<4\|1<<10)) {
	wwan_rfkill = rfkill_alloc("dell-wwan",
	&platform_device->dev,
	RFKILL_TYPE_WWAN,
	&dell_rfkill_ops, (void *) 3);
	if (!wwan_rfkill) {
	ret = -ENOMEM;
	goto err_wwan;
	}
	ret = rfkill_register(wwan_rfkill);
	if (ret)
	goto err_wwan;
	}

	return 0;
	err_wwan:
	rfkill_destroy(wwan_rfkill);
	if (bluetooth_rfkill)
	rfkill_unregister(bluetooth_rfkill);
	err_bluetooth:
	rfkill_destroy(bluetooth_rfkill);
	if (wifi_rfkill)
	rfkill_unregister(wifi_rfkill);
	err_wifi:
	rfkill_destroy(wifi_rfkill);

	return ret;
	}

	static void dell_cleanup_rfkill(void)
	{
	if (wifi_rfkill) {
	rfkill_unregister(wifi_rfkill);
	rfkill_destroy(wifi_rfkill);
	}
	if (bluetooth_rfkill) {
	rfkill_unregister(bluetooth_rfkill);
	rfkill_destroy(bluetooth_rfkill);
	}
	if (wwan_rfkill) {
	rfkill_unregister(wwan_rfkill);
	rfkill_destroy(wwan_rfkill);
	}
	}

	static int dell_send_intensity(struct backlight_device *bd)
	{
	int ret = 0;

	get_buffer();
	buffer->input[0] = find_token_location(BRIGHTNESS_TOKEN);
	buffer->input[1] = bd->props.brightness;

	if (buffer->input[0] == -1) {
	ret = -ENODEV;
	goto out;
	}

	if (power_supply_is_system_supplied() > 0)
	dell_send_request(buffer, 1, 2);
	else
	dell_send_request(buffer, 1, 1);

	out:
	release_buffer();
	return 0;
	}

	static int dell_get_intensity(struct backlight_device *bd)
	{
	int ret = 0;

	get_buffer();
	buffer->input[0] = find_token_location(BRIGHTNESS_TOKEN);

	if (buffer->input[0] == -1) {
	ret = -ENODEV;
	goto out;
	}

	if (power_supply_is_system_supplied() > 0)
	dell_send_request(buffer, 0, 2);
	else
	dell_send_request(buffer, 0, 1);

	ret = buffer->output[1];

	out:
	release_buffer();
	return ret;
	}

	static const struct backlight_ops dell_ops = {
	.get_brightness = dell_get_intensity,
	.update_status = dell_send_intensity,
	};

	static void touchpad_led_on(void)
	{
	int command = 0x97;
	char data = 1;
	i8042_command(&data, command \| 1 << 12);
	}

	static void touchpad_led_off(void)
	{
	int command = 0x97;
	char data = 2;
	i8042_command(&data, command \| 1 << 12);
	}

	static void touchpad_led_set(struct led_classdev *led_cdev,
	enum led_brightness value)
	{
	if (value > 0)
	touchpad_led_on();
	else
	touchpad_led_off();
	}

	static struct led_classdev touchpad_led = {
	.name = "dell-laptop::touchpad",
	.brightness_set = touchpad_led_set,
	.flags = LED_CORE_SUSPENDRESUME,
	};

	static int __devinit touchpad_led_init(struct device *dev)
	{
	return led_classdev_register(dev, &touchpad_led);
	}

	static void touchpad_led_exit(void)
	{
	led_classdev_unregister(&touchpad_led);
	}

	static bool dell_laptop_i8042_filter(unsigned char data, unsigned char str,
	struct serio *port)
	{
	static bool extended;

	if (str & 0x20)
	return false;

	if (unlikely(data == 0xe0)) {
	extended = true;
	return false;
	} else if (unlikely(extended)) {
	switch (data) {
	case 0x8:
	schedule_delayed_work(&dell_rfkill_work,
	round_jiffies_relative(HZ));
	break;
	}
	extended = false;
	}

	return false;
	}

	static int __init dell_init(void)
	{
	int max_intensity = 0;
	int ret;

	if (!dmi_check_system(dell_device_table))
	return -ENODEV;

	quirks = NULL;
	/* find if this machine support other functions */
	dmi_check_system(dell_quirks);

	dmi_walk(find_tokens, NULL);

	if (!da_tokens) {
	pr_info("Unable to find dmi tokens\n");
	return -ENODEV;
	}

	ret = platform_driver_register(&platform_driver);
	if (ret)
	goto fail_platform_driver;
	platform_device = platform_device_alloc("dell-laptop", -1);
	if (!platform_device) {
	ret = -ENOMEM;
	goto fail_platform_device1;
	}
	ret = platform_device_add(platform_device);
	if (ret)
	goto fail_platform_device2;

	/*
	* Allocate buffer below 4GB for SMI data--only 32-bit physical addr
	* is passed to SMI handler.
	*/
	bufferpage = alloc_page(GFP_KERNEL \| GFP_DMA32);

	if (!bufferpage)
	goto fail_buffer;
	buffer = page_address(bufferpage);

	ret = dell_setup_rfkill();

	if (ret) {
	pr_warn("Unable to setup rfkill\n");
	goto fail_rfkill;
	}

	ret = i8042_install_filter(dell_laptop_i8042_filter);
	if (ret) {
	pr_warn("Unable to install key filter\n");
	goto fail_filter;
	}

	if (quirks && quirks->touchpad_led)
	touchpad_led_init(&platform_device->dev);

	dell_laptop_dir = debugfs_create_dir("dell_laptop", NULL);
	if (dell_laptop_dir != NULL)
	debugfs_create_file("rfkill", 0444, dell_laptop_dir, NULL,
	&dell_debugfs_fops);

	#ifdef CONFIG_ACPI
	/* In the event of an ACPI backlight being available, don't
	* register the platform controller.
	*/
	if (acpi_video_backlight_support())
	return 0;
	#endif

	get_buffer();
	buffer->input[0] = find_token_location(BRIGHTNESS_TOKEN);
	if (buffer->input[0] != -1) {
	dell_send_request(buffer, 0, 2);
	max_intensity = buffer->output[3];
	}
	release_buffer();

	if (max_intensity) {
	struct backlight_properties props;
	memset(&props, 0, sizeof(struct backlight_properties));
	props.type = BACKLIGHT_PLATFORM;
	props.max_brightness = max_intensity;
	dell_backlight_device = backlight_device_register("dell_backlight",
	&platform_device->dev,
	NULL,
	&dell_ops,
	&props);

	if (IS_ERR(dell_backlight_device)) {
	ret = PTR_ERR(dell_backlight_device);
	dell_backlight_device = NULL;
	goto fail_backlight;
	}

	dell_backlight_device->props.brightness =
	dell_get_intensity(dell_backlight_device);
	backlight_update_status(dell_backlight_device);
	}

	return 0;

	fail_backlight:
	i8042_remove_filter(dell_laptop_i8042_filter);
	cancel_delayed_work_sync(&dell_rfkill_work);
	fail_filter:
	dell_cleanup_rfkill();
	fail_rfkill:
	free_page((unsigned long)bufferpage);
	fail_buffer:
	platform_device_del(platform_device);
	fail_platform_device2:
	platform_device_put(platform_device);
	fail_platform_device1:
	platform_driver_unregister(&platform_driver);
	fail_platform_driver:
	kfree(da_tokens);
	return ret;
	}

	static void __exit dell_exit(void)
	{
	debugfs_remove_recursive(dell_laptop_dir);
	if (quirks && quirks->touchpad_led)
	touchpad_led_exit();
	i8042_remove_filter(dell_laptop_i8042_filter);
	cancel_delayed_work_sync(&dell_rfkill_work);
	backlight_device_unregister(dell_backlight_device);
	dell_cleanup_rfkill();
	if (platform_device) {
	platform_device_unregister(platform_device);
	platform_driver_unregister(&platform_driver);
	}
	kfree(da_tokens);
	free_page((unsigned long)buffer);
	}

	module_init(dell_init);
	module_exit(dell_exit);

	MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
	MODULE_DESCRIPTION("Dell laptop driver");
	MODULE_LICENSE("GPL");