text: /*
   * Samsung Laptop driver
   *
   * Copyright (C) 2009,2011 Greg Kroah-Hartman (gregkh@suse.de)
   * Copyright (C) 2009,2011 Novell 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/kernel.h>
  #include <linux/init.h>
  #include <linux/module.h>
  #include <linux/delay.h>
  #include <linux/pci.h>
  #include <linux/backlight.h>
  #include <linux/leds.h>
  #include <linux/fb.h>
  #include <linux/dmi.h>
  #include <linux/platform_device.h>
  #include <linux/rfkill.h>
  #include <linux/acpi.h>
  #include <linux/seq_file.h>
  #include <linux/debugfs.h>
  #include <linux/ctype.h>
  #include <linux/efi.h>
  #include <acpi/video.h>
  
  /*
   * This driver is needed because a number of Samsung laptops do not hook
   * their control settings through ACPI.  So we have to poke around in the
   * BIOS to do things like brightness values, and "special" key controls.
   */
  
  /*
   * We have 0 - 8 as valid brightness levels.  The specs say that level 0 should
   * be reserved by the BIOS (which really doesn't make much sense), we tell
   * userspace that the value is 0 - 7 and then just tell the hardware 1 - 8
   */
  #define MAX_BRIGHT	0x07
  
  
  #define SABI_IFACE_MAIN			0x00
  #define SABI_IFACE_SUB			0x02
  #define SABI_IFACE_COMPLETE		0x04
  #define SABI_IFACE_DATA			0x05
  
  #define WL_STATUS_WLAN			0x0
  #define WL_STATUS_BT			0x2
  
  /* Structure get/set data using sabi */
  struct sabi_data {
  	union {
  		struct {
  			u32 d0;
  			u32 d1;
  			u16 d2;
  			u8  d3;
  		};
  		u8 data[11];
  	};
  };
  
  struct sabi_header_offsets {
  	u8 port;
  	u8 re_mem;
  	u8 iface_func;
  	u8 en_mem;
  	u8 data_offset;
  	u8 data_segment;
  };
  
  struct sabi_commands {
  	/*
  	 * Brightness is 0 - 8, as described above.
  	 * Value 0 is for the BIOS to use
  	 */
  	u16 get_brightness;
  	u16 set_brightness;
  
  	/*
  	 * first byte:
  	 * 0x00 - wireless is off
  	 * 0x01 - wireless is on
  	 * second byte:
  	 * 0x02 - 3G is off
  	 * 0x03 - 3G is on
  	 * TODO, verify 3G is correct, that doesn't seem right...
  	 */
  	u16 get_wireless_button;
  	u16 set_wireless_button;
  
  	/* 0 is off, 1 is on */
  	u16 get_backlight;
  	u16 set_backlight;
  
  	/*
  	 * 0x80 or 0x00 - no action
  	 * 0x81 - recovery key pressed
  	 */
  	u16 get_recovery_mode;
  	u16 set_recovery_mode;
  
  	/*
  	 * on seclinux: 0 is low, 1 is high,
  	 * on swsmi: 0 is normal, 1 is silent, 2 is turbo
  	 */
  	u16 get_performance_level;
  	u16 set_performance_level;
  
  	/* 0x80 is off, 0x81 is on */
  	u16 get_battery_life_extender;
  	u16 set_battery_life_extender;
  
  	/* 0x80 is off, 0x81 is on */
  	u16 get_usb_charge;
  	u16 set_usb_charge;
  
  	/* the first byte is for bluetooth and the third one is for wlan */
  	u16 get_wireless_status;
  	u16 set_wireless_status;
  
  	/* 0x81 to read, (0x82 | level << 8) to set, 0xaabb to enable */
  	u16 kbd_backlight;
  
  	/*
  	 * Tell the BIOS that Linux is running on this machine.
  	 * 81 is on, 80 is off
  	 */
  	u16 set_linux;
  };
  
  struct sabi_performance_level {
  	const char *name;
  	u16 value;
  };
  
  struct sabi_config {
  	int sabi_version;
  	const char *test_string;
  	u16 main_function;
  	const struct sabi_header_offsets header_offsets;
  	const struct sabi_commands commands;
  	const struct sabi_performance_level performance_levels[4];
  	u8 min_brightness;
  	u8 max_brightness;
  };
  
  static const struct sabi_config sabi_configs[] = {
  	{
  		/* I don't know if it is really 2, but it it is
  		 * less than 3 anyway */
  		.sabi_version = 2,
  
  		.test_string = "SECLINUX",
  
  		.main_function = 0x4c49,
  
  		.header_offsets = {
  			.port = 0x00,
  			.re_mem = 0x02,
  			.iface_func = 0x03,
  			.en_mem = 0x04,
  			.data_offset = 0x05,
  			.data_segment = 0x07,
  		},
  
  		.commands = {
  			.get_brightness = 0x00,
  			.set_brightness = 0x01,
  
  			.get_wireless_button = 0x02,
  			.set_wireless_button = 0x03,
  
  			.get_backlight = 0x04,
  			.set_backlight = 0x05,
  
  			.get_recovery_mode = 0x06,
  			.set_recovery_mode = 0x07,
  
  			.get_performance_level = 0x08,
  			.set_performance_level = 0x09,
  
  			.get_battery_life_extender = 0xFFFF,
  			.set_battery_life_extender = 0xFFFF,
  
  			.get_usb_charge = 0xFFFF,
  			.set_usb_charge = 0xFFFF,
  
  			.get_wireless_status = 0xFFFF,
  			.set_wireless_status = 0xFFFF,
  
  			.kbd_backlight = 0xFFFF,
  
  			.set_linux = 0x0a,
  		},
  
  		.performance_levels = {
  			{
  				.name = "silent",
  				.value = 0,
  			},
  			{
  				.name = "normal",
  				.value = 1,
  			},
  			{ },
  		},
  		.min_brightness = 1,
  		.max_brightness = 8,
  	},
  	{
  		.sabi_version = 3,
  
  		.test_string = "SwSmi@",
  
  		.main_function = 0x5843,
  
  		.header_offsets = {
  			.port = 0x00,
  			.re_mem = 0x04,
  			.iface_func = 0x02,
  			.en_mem = 0x03,
  			.data_offset = 0x05,
  			.data_segment = 0x07,
  		},
  
  		.commands = {
  			.get_brightness = 0x10,
  			.set_brightness = 0x11,
  
  			.get_wireless_button = 0x12,
  			.set_wireless_button = 0x13,
  
  			.get_backlight = 0x2d,
  			.set_backlight = 0x2e,
  
  			.get_recovery_mode = 0xff,
  			.set_recovery_mode = 0xff,
  
  			.get_performance_level = 0x31,
  			.set_performance_level = 0x32,
  
  			.get_battery_life_extender = 0x65,
  			.set_battery_life_extender = 0x66,
  
  			.get_usb_charge = 0x67,
  			.set_usb_charge = 0x68,
  
  			.get_wireless_status = 0x69,
  			.set_wireless_status = 0x6a,
  
  			.kbd_backlight = 0x78,
  
  			.set_linux = 0xff,
  		},
  
  		.performance_levels = {
  			{
  				.name = "normal",
  				.value = 0,
  			},
  			{
  				.name = "silent",
  				.value = 1,
  			},
  			{
  				.name = "overclock",
  				.value = 2,
  			},
  			{ },
  		},
  		.min_brightness = 0,
  		.max_brightness = 8,
  	},
  	{ },
  };
  
  /*
   * samsung-laptop/    - debugfs root directory
   *   f0000_segment    - dump f0000 segment
   *   command          - current command
   *   data             - current data
   *   d0, d1, d2, d3   - data fields
   *   call             - call SABI using command and data
   *
   * This allow to call arbitrary sabi commands wihout
   * modifying the driver at all.
   * For example, setting the keyboard backlight brightness to 5
   *
   *  echo 0x78 > command
   *  echo 0x0582 > d0
   *  echo 0 > d1
   *  echo 0 > d2
   *  echo 0 > d3
   *  cat call
   */
  
  struct samsung_laptop_debug {
  	struct dentry *root;
  	struct sabi_data data;
  	u16 command;
  
  	struct debugfs_blob_wrapper f0000_wrapper;
  	struct debugfs_blob_wrapper data_wrapper;
  	struct debugfs_blob_wrapper sdiag_wrapper;
  };
  
  struct samsung_laptop;
  
  struct samsung_rfkill {
  	struct samsung_laptop *samsung;
  	struct rfkill *rfkill;
  	enum rfkill_type type;
  };
  
  struct samsung_laptop {
  	const struct sabi_config *config;
  
  	void __iomem *sabi;
  	void __iomem *sabi_iface;
  	void __iomem *f0000_segment;
  
  	struct mutex sabi_mutex;
  
  	struct platform_device *platform_device;
  	struct backlight_device *backlight_device;
  
  	struct samsung_rfkill wlan;
  	struct samsung_rfkill bluetooth;
  
  	struct led_classdev kbd_led;
  	int kbd_led_wk;
  	struct workqueue_struct *led_workqueue;
  	struct work_struct kbd_led_work;
  
  	struct samsung_laptop_debug debug;
  	struct samsung_quirks *quirks;
  
  	bool handle_backlight;
  	bool has_stepping_quirk;
  
  	char sdiag[64];
  };
  
  struct samsung_quirks {
  	bool broken_acpi_video;
  };
  
  static struct samsung_quirks samsung_unknown = {};
  
  static struct samsung_quirks samsung_broken_acpi_video = {
  	.broken_acpi_video = true,
  };
  
  static bool force;
  module_param(force, bool, 0);
  MODULE_PARM_DESC(force,
  		"Disable the DMI check and forces the driver to be loaded");
  
  static bool debug;
  module_param(debug, bool, S_IRUGO | S_IWUSR);
  MODULE_PARM_DESC(debug, "Debug enabled or not");
  
  static int sabi_command(struct samsung_laptop *samsung, u16 command,
  			struct sabi_data *in,
  			struct sabi_data *out)
  {
  	const struct sabi_config *config = samsung->config;
  	int ret = 0;
  	u16 port = readw(samsung->sabi + config->header_offsets.port);
  	u8 complete, iface_data;
  
  	mutex_lock(&samsung->sabi_mutex);
  
  	if (debug) {
  		if (in)
  			pr_info("SABI command:0x%04x "
  				"data:{0x%08x, 0x%08x, 0x%04x, 0x%02x}",
  				command, in->d0, in->d1, in->d2, in->d3);
  		else
  			pr_info("SABI command:0x%04x", command);
  	}
  
  	/* enable memory to be able to write to it */
  	outb(readb(samsung->sabi + config->header_offsets.en_mem), port);
  
  	/* write out the command */
  	writew(config->main_function, samsung->sabi_iface + SABI_IFACE_MAIN);
  	writew(command, samsung->sabi_iface + SABI_IFACE_SUB);
  	writeb(0, samsung->sabi_iface + SABI_IFACE_COMPLETE);
  	if (in) {
  		writel(in->d0, samsung->sabi_iface + SABI_IFACE_DATA);
  		writel(in->d1, samsung->sabi_iface + SABI_IFACE_DATA + 4);
  		writew(in->d2, samsung->sabi_iface + SABI_IFACE_DATA + 8);
  		writeb(in->d3, samsung->sabi_iface + SABI_IFACE_DATA + 10);
  	}
  	outb(readb(samsung->sabi + config->header_offsets.iface_func), port);
  
  	/* write protect memory to make it safe */
  	outb(readb(samsung->sabi + config->header_offsets.re_mem), port);
  
  	/* see if the command actually succeeded */
  	complete = readb(samsung->sabi_iface + SABI_IFACE_COMPLETE);
  	iface_data = readb(samsung->sabi_iface + SABI_IFACE_DATA);
  
  	/* iface_data = 0xFF happens when a command is not known
  	 * so we only add a warning in debug mode since we will
  	 * probably issue some unknown command at startup to find
  	 * out which features are supported */
  	if (complete != 0xaa || (iface_data == 0xff && debug))
  		pr_warn("SABI command 0x%04x failed with"
  			" completion flag 0x%02x and interface data 0x%02x",
  			command, complete, iface_data);
  
  	if (complete != 0xaa || iface_data == 0xff) {
  		ret = -EINVAL;
  		goto exit;
  	}
  
  	if (out) {
  		out->d0 = readl(samsung->sabi_iface + SABI_IFACE_DATA);
  		out->d1 = readl(samsung->sabi_iface + SABI_IFACE_DATA + 4);
  		out->d2 = readw(samsung->sabi_iface + SABI_IFACE_DATA + 2);
  		out->d3 = readb(samsung->sabi_iface + SABI_IFACE_DATA + 1);
  	}
  
  	if (debug && out) {
  		pr_info("SABI return data:{0x%08x, 0x%08x, 0x%04x, 0x%02x}",
  			out->d0, out->d1, out->d2, out->d3);
  	}
  
  exit:
  	mutex_unlock(&samsung->sabi_mutex);
  	return ret;
  }
  
  /* simple wrappers usable with most commands */
  static int sabi_set_commandb(struct samsung_laptop *samsung,
  			     u16 command, u8 data)
  {
  	struct sabi_data in = { { { .d0 = 0, .d1 = 0, .d2 = 0, .d3 = 0 } } };
  
  	in.data[0] = data;
  	return sabi_command(samsung, command, &in, NULL);
  }
  
  static int read_brightness(struct samsung_laptop *samsung)
  {
  	const struct sabi_config *config = samsung->config;
  	const struct sabi_commands *commands = &samsung->config->commands;
  	struct sabi_data sretval;
  	int user_brightness = 0;
  	int retval;
  
  	retval = sabi_command(samsung, commands->get_brightness,
  			      NULL, &sretval);
  	if (retval)
  		return retval;
  
  	user_brightness = sretval.data[0];
  	if (user_brightness > config->min_brightness)
  		user_brightness -= config->min_brightness;
  	else
  		user_brightness = 0;
  
  	return user_brightness;
  }
  
  static void set_brightness(struct samsung_laptop *samsung, u8 user_brightness)
  {
  	const struct sabi_config *config = samsung->config;
  	const struct sabi_commands *commands = &samsung->config->commands;
  	u8 user_level = user_brightness + config->min_brightness;
  
  	if (samsung->has_stepping_quirk && user_level != 0) {
  		/*
  		 * short circuit if the specified level is what's already set
  		 * to prevent the screen from flickering needlessly
  		 */
  		if (user_brightness == read_brightness(samsung))
  			return;
  
  		sabi_set_commandb(samsung, commands->set_brightness, 0);
  	}
  
  	sabi_set_commandb(samsung, commands->set_brightness, user_level);
  }
  
  static int get_brightness(struct backlight_device *bd)
  {
  	struct samsung_laptop *samsung = bl_get_data(bd);
  
  	return read_brightness(samsung);
  }
  
  static void check_for_stepping_quirk(struct samsung_laptop *samsung)
  {
  	int initial_level;
  	int check_level;
  	int orig_level = read_brightness(samsung);
  
  	/*
  	 * Some laptops exhibit the strange behaviour of stepping toward
  	 * (rather than setting) the brightness except when changing to/from
  	 * brightness level 0. This behaviour is checked for here and worked
  	 * around in set_brightness.
  	 */
  
  	if (orig_level == 0)
  		set_brightness(samsung, 1);
  
  	initial_level = read_brightness(samsung);
  
  	if (initial_level <= 2)
  		check_level = initial_level + 2;
  	else
  		check_level = initial_level - 2;
  
  	samsung->has_stepping_quirk = false;
  	set_brightness(samsung, check_level);
  
  	if (read_brightness(samsung) != check_level) {
  		samsung->has_stepping_quirk = true;
  		pr_info("enabled workaround for brightness stepping quirk\n");
  	}
  
  	set_brightness(samsung, orig_level);
  }
  
  static int update_status(struct backlight_device *bd)
  {
  	struct samsung_laptop *samsung = bl_get_data(bd);
  	const struct sabi_commands *commands = &samsung->config->commands;
  
  	set_brightness(samsung, bd->props.brightness);
  
  	if (bd->props.power == FB_BLANK_UNBLANK)
  		sabi_set_commandb(samsung, commands->set_backlight, 1);
  	else
  		sabi_set_commandb(samsung, commands->set_backlight, 0);
  
  	return 0;
  }
  
  static const struct backlight_ops backlight_ops = {
  	.get_brightness	= get_brightness,
  	.update_status	= update_status,
  };
  
  static int seclinux_rfkill_set(void *data, bool blocked)
  {
  	struct samsung_rfkill *srfkill = data;
  	struct samsung_laptop *samsung = srfkill->samsung;
  	const struct sabi_commands *commands = &samsung->config->commands;
  
  	return sabi_set_commandb(samsung, commands->set_wireless_button,
  				 !blocked);
  }
  
  static struct rfkill_ops seclinux_rfkill_ops = {
  	.set_block = seclinux_rfkill_set,
  };
  
  static int swsmi_wireless_status(struct samsung_laptop *samsung,
  				 struct sabi_data *data)
  {
  	const struct sabi_commands *commands = &samsung->config->commands;
  
  	return sabi_command(samsung, commands->get_wireless_status,
  			    NULL, data);
  }
  
  static int swsmi_rfkill_set(void *priv, bool blocked)
  {
  	struct samsung_rfkill *srfkill = priv;
  	struct samsung_laptop *samsung = srfkill->samsung;
  	const struct sabi_commands *commands = &samsung->config->commands;
  	struct sabi_data data;
  	int ret, i;
  
  	ret = swsmi_wireless_status(samsung, &data);
  	if (ret)
  		return ret;
  
  	/* Don't set the state for non-present devices */
  	for (i = 0; i < 4; i++)
  		if (data.data[i] == 0x02)
  			data.data[1] = 0;
  
  	if (srfkill->type == RFKILL_TYPE_WLAN)
  		data.data[WL_STATUS_WLAN] = !blocked;
  	else if (srfkill->type == RFKILL_TYPE_BLUETOOTH)
  		data.data[WL_STATUS_BT] = !blocked;
  
  	return sabi_command(samsung, commands->set_wireless_status,
  			    &data, &data);
  }
  
  static void swsmi_rfkill_query(struct rfkill *rfkill, void *priv)
  {
  	struct samsung_rfkill *srfkill = priv;
  	struct samsung_laptop *samsung = srfkill->samsung;
  	struct sabi_data data;
  	int ret;
  
  	ret = swsmi_wireless_status(samsung, &data);
  	if (ret)
  		return ;
  
  	if (srfkill->type == RFKILL_TYPE_WLAN)
  		ret = data.data[WL_STATUS_WLAN];
  	else if (srfkill->type == RFKILL_TYPE_BLUETOOTH)
  		ret = data.data[WL_STATUS_BT];
  	else
  		return ;
  
  	rfkill_set_sw_state(rfkill, !ret);
  }
  
  static struct rfkill_ops swsmi_rfkill_ops = {
  	.set_block = swsmi_rfkill_set,
  	.query = swsmi_rfkill_query,
  };
  
  static ssize_t get_performance_level(struct device *dev,
  				     struct device_attribute *attr, char *buf)
  {
  	struct samsung_laptop *samsung = dev_get_drvdata(dev);
  	const struct sabi_config *config = samsung->config;
  	const struct sabi_commands *commands = &config->commands;
  	struct sabi_data sretval;
  	int retval;
  	int i;
  
  	/* Read the state */
  	retval = sabi_command(samsung, commands->get_performance_level,
  			      NULL, &sretval);
  	if (retval)
  		return retval;
  
  	/* The logic is backwards, yeah, lots of fun... */
  	for (i = 0; config->performance_levels[i].name; ++i) {
  		if (sretval.data[0] == config->performance_levels[i].value)
  			return sprintf(buf, "%s\n", config->performance_levels[i].name);
  	}
  	return sprintf(buf, "%s\n", "unknown");
  }
  
  static ssize_t set_performance_level(struct device *dev,
  				struct device_attribute *attr, const char *buf,
  				size_t count)
  {
  	struct samsung_laptop *samsung = dev_get_drvdata(dev);
  	const struct sabi_config *config = samsung->config;
  	const struct sabi_commands *commands = &config->commands;
  	int i;
  
  	if (count < 1)
  		return count;
  
  	for (i = 0; config->performance_levels[i].name; ++i) {
  		const struct sabi_performance_level *level =
  			&config->performance_levels[i];
  		if (!strncasecmp(level->name, buf, strlen(level->name))) {
  			sabi_set_commandb(samsung,
  					  commands->set_performance_level,
  					  level->value);
  			break;
  		}
  	}
  
  	if (!config->performance_levels[i].name)
  		return -EINVAL;
  
  	return count;
  }
  
  static DEVICE_ATTR(performance_level, S_IWUSR | S_IRUGO,
  		   get_performance_level, set_performance_level);
  
  static int read_battery_life_extender(struct samsung_laptop *samsung)
  {
  	const struct sabi_commands *commands = &samsung->config->commands;
  	struct sabi_data data;
  	int retval;
  
  	if (commands->get_battery_life_extender == 0xFFFF)
  		return -ENODEV;
  
  	memset(&data, 0, sizeof(data));
  	data.data[0] = 0x80;
  	retval = sabi_command(samsung, commands->get_battery_life_extender,
  			      &data, &data);
  
  	if (retval)
  		return retval;
  
  	if (data.data[0] != 0 && data.data[0] != 1)
  		return -ENODEV;
  
  	return data.data[0];
  }
  
  static int write_battery_life_extender(struct samsung_laptop *samsung,
  				       int enabled)
  {
  	const struct sabi_commands *commands = &samsung->config->commands;
  	struct sabi_data data;
  
  	memset(&data, 0, sizeof(data));
  	data.data[0] = 0x80 | enabled;
  	return sabi_command(samsung, commands->set_battery_life_extender,
  			    &data, NULL);
  }
  
  static ssize_t get_battery_life_extender(struct device *dev,
  					 struct device_attribute *attr,
  					 char *buf)
  {
  	struct samsung_laptop *samsung = dev_get_drvdata(dev);
  	int ret;
  
  	ret = read_battery_life_extender(samsung);
  	if (ret < 0)
  		return ret;
  
  	return sprintf(buf, "%d\n", ret);
  }
  
  static ssize_t set_battery_life_extender(struct device *dev,
  					struct device_attribute *attr,
  					const char *buf, size_t count)
  {
  	struct samsung_laptop *samsung = dev_get_drvdata(dev);
  	int ret, value;
  
  	if (!count || sscanf(buf, "%i", &value) != 1)
  		return -EINVAL;
  
  	ret = write_battery_life_extender(samsung, !!value);
  	if (ret < 0)
  		return ret;
  
  	return count;
  }
  
  static DEVICE_ATTR(battery_life_extender, S_IWUSR | S_IRUGO,
  		   get_battery_life_extender, set_battery_life_extender);
  
  static int read_usb_charge(struct samsung_laptop *samsung)
  {
  	const struct sabi_commands *commands = &samsung->config->commands;
  	struct sabi_data data;
  	int retval;
  
  	if (commands->get_usb_charge == 0xFFFF)
  		return -ENODEV;
  
  	memset(&data, 0, sizeof(data));
  	data.data[0] = 0x80;
  	retval = sabi_command(samsung, commands->get_usb_charge,
  			      &data, &data);
  
  	if (retval)
  		return retval;
  
  	if (data.data[0] != 0 && data.data[0] != 1)
  		return -ENODEV;
  
  	return data.data[0];
  }
  
  static int write_usb_charge(struct samsung_laptop *samsung,
  			    int enabled)
  {
  	const struct sabi_commands *commands = &samsung->config->commands;
  	struct sabi_data data;
  
  	memset(&data, 0, sizeof(data));
  	data.data[0] = 0x80 | enabled;
  	return sabi_command(samsung, commands->set_usb_charge,
  			    &data, NULL);
  }
  
  static ssize_t get_usb_charge(struct device *dev,
  			      struct device_attribute *attr,
  			      char *buf)
  {
  	struct samsung_laptop *samsung = dev_get_drvdata(dev);
  	int ret;
  
  	ret = read_usb_charge(samsung);
  	if (ret < 0)
  		return ret;
  
  	return sprintf(buf, "%d\n", ret);
  }
  
  static ssize_t set_usb_charge(struct device *dev,
  			      struct device_attribute *attr,
  			      const char *buf, size_t count)
  {
  	struct samsung_laptop *samsung = dev_get_drvdata(dev);
  	int ret, value;
  
  	if (!count || sscanf(buf, "%i", &value) != 1)
  		return -EINVAL;
  
  	ret = write_usb_charge(samsung, !!value);
  	if (ret < 0)
  		return ret;
  
  	return count;
  }
  
  static DEVICE_ATTR(usb_charge, S_IWUSR | S_IRUGO,
  		   get_usb_charge, set_usb_charge);
  
  static struct attribute *platform_attributes[] = {
  	&dev_attr_performance_level.attr,
  	&dev_attr_battery_life_extender.attr,
  	&dev_attr_usb_charge.attr,
  	NULL
  };
  
  static int find_signature(void __iomem *memcheck, const char *testStr)
  {
  	int i = 0;
  	int loca;
  
  	for (loca = 0; loca < 0xffff; loca++) {
  		char temp = readb(memcheck + loca);
  
  		if (temp == testStr[i]) {
  			if (i == strlen(testStr)-1)
  				break;
  			++i;
  		} else {
  			i = 0;
  		}
  	}
  	return loca;
  }
  
  static void samsung_rfkill_exit(struct samsung_laptop *samsung)
  {
  	if (samsung->wlan.rfkill) {
  		rfkill_unregister(samsung->wlan.rfkill);
  		rfkill_destroy(samsung->wlan.rfkill);
  		samsung->wlan.rfkill = NULL;
  	}
  	if (samsung->bluetooth.rfkill) {
  		rfkill_unregister(samsung->bluetooth.rfkill);
  		rfkill_destroy(samsung->bluetooth.rfkill);
  		samsung->bluetooth.rfkill = NULL;
  	}
  }
  
  static int samsung_new_rfkill(struct samsung_laptop *samsung,
  			      struct samsung_rfkill *arfkill,
  			      const char *name, enum rfkill_type type,
  			      const struct rfkill_ops *ops,
  			      int blocked)
  {
  	struct rfkill **rfkill = &arfkill->rfkill;
  	int ret;
  
  	arfkill->type = type;
  	arfkill->samsung = samsung;
  
  	*rfkill = rfkill_alloc(name, &samsung->platform_device->dev,
  			       type, ops, arfkill);
  
  	if (!*rfkill)
  		return -EINVAL;
  
  	if (blocked != -1)
  		rfkill_init_sw_state(*rfkill, blocked);
  
  	ret = rfkill_register(*rfkill);
  	if (ret) {
  		rfkill_destroy(*rfkill);
  		*rfkill = NULL;
  		return ret;
  	}
  	return 0;
  }
  
  static int __init samsung_rfkill_init_seclinux(struct samsung_laptop *samsung)
  {
  	return samsung_new_rfkill(samsung, &samsung->wlan, "samsung-wlan",
  				  RFKILL_TYPE_WLAN, &seclinux_rfkill_ops, -1);
  }
  
  static int __init samsung_rfkill_init_swsmi(struct samsung_laptop *samsung)
  {
  	struct sabi_data data;
  	int ret;
  
  	ret = swsmi_wireless_status(samsung, &data);
  	if (ret) {
  		/* Some swsmi laptops use the old seclinux way to control
  		 * wireless devices */
  		if (ret == -EINVAL)
  			ret = samsung_rfkill_init_seclinux(samsung);
  		return ret;
  	}
  
  	/* 0x02 seems to mean that the device is no present/available */
  
  	if (data.data[WL_STATUS_WLAN] != 0x02)
  		ret = samsung_new_rfkill(samsung, &samsung->wlan,
  					 "samsung-wlan",
  					 RFKILL_TYPE_WLAN,
  					 &swsmi_rfkill_ops,
  					 !data.data[WL_STATUS_WLAN]);
  	if (ret)
  		goto exit;
  
  	if (data.data[WL_STATUS_BT] != 0x02)
  		ret = samsung_new_rfkill(samsung, &samsung->bluetooth,
  					 "samsung-bluetooth",
  					 RFKILL_TYPE_BLUETOOTH,
  					 &swsmi_rfkill_ops,
  					 !data.data[WL_STATUS_BT]);
  	if (ret)
  		goto exit;
  
  exit:
  	if (ret)
  		samsung_rfkill_exit(samsung);
  
  	return ret;
  }
  
  static int __init samsung_rfkill_init(struct samsung_laptop *samsung)
  {
  	if (samsung->config->sabi_version == 2)
  		return samsung_rfkill_init_seclinux(samsung);
  	if (samsung->config->sabi_version == 3)
  		return samsung_rfkill_init_swsmi(samsung);
  	return 0;
  }
  
  static int kbd_backlight_enable(struct samsung_laptop *samsung)
  {
  	const struct sabi_commands *commands = &samsung->config->commands;
  	struct sabi_data data;
  	int retval;
  
  	if (commands->kbd_backlight == 0xFFFF)
  		return -ENODEV;
  
  	memset(&data, 0, sizeof(data));
  	data.d0 = 0xaabb;
  	retval = sabi_command(samsung, commands->kbd_backlight,
  			      &data, &data);
  
  	if (retval)
  		return retval;
  
  	if (data.d0 != 0xccdd)
  		return -ENODEV;
  	return 0;
  }
  
  static int kbd_backlight_read(struct samsung_laptop *samsung)
  {
  	const struct sabi_commands *commands = &samsung->config->commands;
  	struct sabi_data data;
  	int retval;
  
  	memset(&data, 0, sizeof(data));
  	data.data[0] = 0x81;
  	retval = sabi_command(samsung, commands->kbd_backlight,
  			      &data, &data);
  
  	if (retval)
  		return retval;
  
  	return data.data[0];
  }
  
  static int kbd_backlight_write(struct samsung_laptop *samsung, int brightness)
  {
  	const struct sabi_commands *commands = &samsung->config->commands;
  	struct sabi_data data;
  
  	memset(&data, 0, sizeof(data));
  	data.d0 = 0x82 | ((brightness & 0xFF) << 8);
  	return sabi_command(samsung, commands->kbd_backlight,
  			    &data, NULL);
  }
  
  static void kbd_led_update(struct work_struct *work)
  {
  	struct samsung_laptop *samsung;
  
  	samsung = container_of(work, struct samsung_laptop, kbd_led_work);
  	kbd_backlight_write(samsung, samsung->kbd_led_wk);
  }
  
  static void kbd_led_set(struct led_classdev *led_cdev,
  			enum led_brightness value)
  {
  	struct samsung_laptop *samsung;
  
  	samsung = container_of(led_cdev, struct samsung_laptop, kbd_led);
  
  	if (value > samsung->kbd_led.max_brightness)
  		value = samsung->kbd_led.max_brightness;
  	else if (value < 0)
  		value = 0;
  
  	samsung->kbd_led_wk = value;
  	queue_work(samsung->led_workqueue, &samsung->kbd_led_work);
  }
  
  static enum led_brightness kbd_led_get(struct led_classdev *led_cdev)
  {
  	struct samsung_laptop *samsung;
  
  	samsung = container_of(led_cdev, struct samsung_laptop, kbd_led);
  	return kbd_backlight_read(samsung);
  }
  
  static void samsung_leds_exit(struct samsung_laptop *samsung)
  {
  	if (!IS_ERR_OR_NULL(samsung->kbd_led.dev))
  		led_classdev_unregister(&samsung->kbd_led);
  	if (samsung->led_workqueue)
  		destroy_workqueue(samsung->led_workqueue);
  }
  
  static int __init samsung_leds_init(struct samsung_laptop *samsung)
  {
  	int ret = 0;
  
  	samsung->led_workqueue = create_singlethread_workqueue("led_workqueue");
  	if (!samsung->led_workqueue)
  		return -ENOMEM;
  
  	if (kbd_backlight_enable(samsung) >= 0) {
  		INIT_WORK(&samsung->kbd_led_work, kbd_led_update);
  
  		samsung->kbd_led.name = "samsung::kbd_backlight";
  		samsung->kbd_led.brightness_set = kbd_led_set;
  		samsung->kbd_led.brightness_get = kbd_led_get;
  		samsung->kbd_led.max_brightness = 8;
  
  		ret = led_classdev_register(&samsung->platform_device->dev,
  					   &samsung->kbd_led);
  	}
  
  	if (ret)
  		samsung_leds_exit(samsung);
  
  	return ret;
  }
  
  static void samsung_backlight_exit(struct samsung_laptop *samsung)
  {
  	if (samsung->backlight_device) {
  		backlight_device_unregister(samsung->backlight_device);
  		samsung->backlight_device = NULL;
  	}
  }
  
  static int __init samsung_backlight_init(struct samsung_laptop *samsung)
  {
  	struct backlight_device *bd;
  	struct backlight_properties props;
  
  	if (!samsung->handle_backlight)
  		return 0;
  
  	memset(&props, 0, sizeof(struct backlight_properties));
  	props.type = BACKLIGHT_PLATFORM;
  	props.max_brightness = samsung->config->max_brightness -
  		samsung->config->min_brightness;
  
  	bd = backlight_device_register("samsung",
  				       &samsung->platform_device->dev,
  				       samsung, &backlight_ops,
  				       &props);
  	if (IS_ERR(bd))
  		return PTR_ERR(bd);
  
  	samsung->backlight_device = bd;
  	samsung->backlight_device->props.brightness = read_brightness(samsung);
  	samsung->backlight_device->props.power = FB_BLANK_UNBLANK;
  	backlight_update_status(samsung->backlight_device);
  
  	return 0;
  }
  
  static umode_t samsung_sysfs_is_visible(struct kobject *kobj,
  				       struct attribute *attr, int idx)
  {
  	struct device *dev = container_of(kobj, struct device, kobj);
  	struct platform_device *pdev = to_platform_device(dev);
  	struct samsung_laptop *samsung = platform_get_drvdata(pdev);
  	bool ok = true;
  
  	if (attr == &dev_attr_performance_level.attr)
  		ok = !!samsung->config->performance_levels[0].name;
  	if (attr == &dev_attr_battery_life_extender.attr)
  		ok = !!(read_battery_life_extender(samsung) >= 0);
  	if (attr == &dev_attr_usb_charge.attr)
  		ok = !!(read_usb_charge(samsung) >= 0);
  
  	return ok ? attr->mode : 0;
  }
  
  static struct attribute_group platform_attribute_group = {
  	.is_visible = samsung_sysfs_is_visible,
  	.attrs = platform_attributes
  };
  
  static void samsung_sysfs_exit(struct samsung_laptop *samsung)
  {
  	struct platform_device *device = samsung->platform_device;
  
  	sysfs_remove_group(&device->dev.kobj, &platform_attribute_group);
  }
  
  static int __init samsung_sysfs_init(struct samsung_laptop *samsung)
  {
  	struct platform_device *device = samsung->platform_device;
  
  	return sysfs_create_group(&device->dev.kobj, &platform_attribute_group);
  
  }
  
  static int show_call(struct seq_file *m, void *data)
  {
  	struct samsung_laptop *samsung = m->private;
  	struct sabi_data *sdata = &samsung->debug.data;
  	int ret;
  
  	seq_printf(m, "SABI 0x%04x {0x%08x, 0x%08x, 0x%04x, 0x%02x}\n",
  		   samsung->debug.command,
  		   sdata->d0, sdata->d1, sdata->d2, sdata->d3);
  
  	ret = sabi_command(samsung, samsung->debug.command, sdata, sdata);
  
  	if (ret) {
  		seq_printf(m, "SABI command 0x%04x failed\n",
  			   samsung->debug.command);
  		return ret;
  	}
  
  	seq_printf(m, "SABI {0x%08x, 0x%08x, 0x%04x, 0x%02x}\n",
  		   sdata->d0, sdata->d1, sdata->d2, sdata->d3);
  	return 0;
  }
  
  static int samsung_debugfs_open(struct inode *inode, struct file *file)
  {
  	return single_open(file, show_call, inode->i_private);
  }
  
  static const struct file_operations samsung_laptop_call_io_ops = {
  	.owner = THIS_MODULE,
  	.open = samsung_debugfs_open,
  	.read = seq_read,
  	.llseek = seq_lseek,
  	.release = single_release,
  };
  
  static void samsung_debugfs_exit(struct samsung_laptop *samsung)
  {
  	debugfs_remove_recursive(samsung->debug.root);
  }
  
  static int samsung_debugfs_init(struct samsung_laptop *samsung)
  {
  	struct dentry *dent;
  
  	samsung->debug.root = debugfs_create_dir("samsung-laptop", NULL);
  	if (!samsung->debug.root) {
  		pr_err("failed to create debugfs directory");
  		goto error_debugfs;
  	}
  
  	samsung->debug.f0000_wrapper.data = samsung->f0000_segment;
  	samsung->debug.f0000_wrapper.size = 0xffff;
  
  	samsung->debug.data_wrapper.data = &samsung->debug.data;
  	samsung->debug.data_wrapper.size = sizeof(samsung->debug.data);
  
  	samsung->debug.sdiag_wrapper.data = samsung->sdiag;
  	samsung->debug.sdiag_wrapper.size = strlen(samsung->sdiag);
  
  	dent = debugfs_create_u16("command", S_IRUGO | S_IWUSR,
  				  samsung->debug.root, &samsung->debug.command);
  	if (!dent)
  		goto error_debugfs;
  
  	dent = debugfs_create_u32("d0", S_IRUGO | S_IWUSR, samsung->debug.root,
  				  &samsung->debug.data.d0);
  	if (!dent)
  		goto error_debugfs;
  
  	dent = debugfs_create_u32("d1", S_IRUGO | S_IWUSR, samsung->debug.root,
  				  &samsung->debug.data.d1);
  	if (!dent)
  		goto error_debugfs;
  
  	dent = debugfs_create_u16("d2", S_IRUGO | S_IWUSR, samsung->debug.root,
  				  &samsung->debug.data.d2);
  	if (!dent)
  		goto error_debugfs;
  
  	dent = debugfs_create_u8("d3", S_IRUGO | S_IWUSR, samsung->debug.root,
  				 &samsung->debug.data.d3);
  	if (!dent)
  		goto error_debugfs;
  
  	dent = debugfs_create_blob("data", S_IRUGO | S_IWUSR,
  				   samsung->debug.root,
  				   &samsung->debug.data_wrapper);
  	if (!dent)
  		goto error_debugfs;
  
  	dent = debugfs_create_blob("f0000_segment", S_IRUSR | S_IWUSR,
  				   samsung->debug.root,
  				   &samsung->debug.f0000_wrapper);
  	if (!dent)
  		goto error_debugfs;
  
  	dent = debugfs_create_file("call", S_IFREG | S_IRUGO,
  				   samsung->debug.root, samsung,
  				   &samsung_laptop_call_io_ops);
  	if (!dent)
  		goto error_debugfs;
  
  	dent = debugfs_create_blob("sdiag", S_IRUGO | S_IWUSR,
  				   samsung->debug.root,
  				   &samsung->debug.sdiag_wrapper);
  	if (!dent)
  		goto error_debugfs;
  
  	return 0;
  
  error_debugfs:
  	samsung_debugfs_exit(samsung);
  	return -ENOMEM;
  }
  
  static void samsung_sabi_exit(struct samsung_laptop *samsung)
  {
  	const struct sabi_config *config = samsung->config;
  
  	/* Turn off "Linux" mode in the BIOS */
  	if (config && config->commands.set_linux != 0xff)
  		sabi_set_commandb(samsung, config->commands.set_linux, 0x80);
  
  	if (samsung->sabi_iface) {
  		iounmap(samsung->sabi_iface);
  		samsung->sabi_iface = NULL;
  	}
  	if (samsung->f0000_segment) {
  		iounmap(samsung->f0000_segment);
  		samsung->f0000_segment = NULL;
  	}
  
  	samsung->config = NULL;
  }
  
  static __init void samsung_sabi_infos(struct samsung_laptop *samsung, int loca,
  				      unsigned int ifaceP)
  {
  	const struct sabi_config *config = samsung->config;
  
  	printk(KERN_DEBUG "This computer supports SABI==%x\n",
  	       loca + 0xf0000 - 6);
  
  	printk(KERN_DEBUG "SABI header:\n");
  	printk(KERN_DEBUG " SMI Port Number = 0x%04x\n",
  	       readw(samsung->sabi + config->header_offsets.port));
  	printk(KERN_DEBUG " SMI Interface Function = 0x%02x\n",
  	       readb(samsung->sabi + config->header_offsets.iface_func));
  	printk(KERN_DEBUG " SMI enable memory buffer = 0x%02x\n",
  	       readb(samsung->sabi + config->header_offsets.en_mem));
  	printk(KERN_DEBUG " SMI restore memory buffer = 0x%02x\n",
  	       readb(samsung->sabi + config->header_offsets.re_mem));
  	printk(KERN_DEBUG " SABI data offset = 0x%04x\n",
  	       readw(samsung->sabi + config->header_offsets.data_offset));
  	printk(KERN_DEBUG " SABI data segment = 0x%04x\n",
  	       readw(samsung->sabi + config->header_offsets.data_segment));
  
  	printk(KERN_DEBUG " SABI pointer = 0x%08x\n", ifaceP);
  }
  
  static void __init samsung_sabi_diag(struct samsung_laptop *samsung)
  {
  	int loca = find_signature(samsung->f0000_segment, "SDiaG@");
  	int i;
  
  	if (loca == 0xffff)
  		return ;
  
  	/* Example:
  	 * Ident: @SDiaG@686XX-N90X3A/966-SEC-07HL-S90X3A
  	 *
  	 * Product name: 90X3A
  	 * BIOS Version: 07HL
  	 */
  	loca += 1;
  	for (i = 0; loca < 0xffff && i < sizeof(samsung->sdiag) - 1; loca++) {
  		char temp = readb(samsung->f0000_segment + loca);
  
  		if (isalnum(temp) || temp == '/' || temp == '-')
  			samsung->sdiag[i++] = temp;
  		else
  			break ;
  	}
  
  	if (debug && samsung->sdiag[0])
  		pr_info("sdiag: %s", samsung->sdiag);
  }
  
  static int __init samsung_sabi_init(struct samsung_laptop *samsung)
  {
  	const struct sabi_config *config = NULL;
  	const struct sabi_commands *commands;
  	unsigned int ifaceP;
  	int ret = 0;
  	int i;
  	int loca;
  
  	samsung->f0000_segment = ioremap_nocache(0xf0000, 0xffff);
  	if (!samsung->f0000_segment) {
  		if (debug || force)
  			pr_err("Can't map the segment at 0xf0000\n");
  		ret = -EINVAL;
  		goto exit;
  	}
  
  	samsung_sabi_diag(samsung);
  
  	/* Try to find one of the signatures in memory to find the header */
  	for (i = 0; sabi_configs[i].test_string != 0; ++i) {
  		samsung->config = &sabi_configs[i];
  		loca = find_signature(samsung->f0000_segment,
  				      samsung->config->test_string);
  		if (loca != 0xffff)
  			break;
  	}
  
  	if (loca == 0xffff) {
  		if (debug || force)
  			pr_err("This computer does not support SABI\n");
  		ret = -ENODEV;
  		goto exit;
  	}
  
  	config = samsung->config;
  	commands = &config->commands;
  
  	/* point to the SMI port Number */
  	loca += 1;
  	samsung->sabi = (samsung->f0000_segment + loca);
  
  	/* Get a pointer to the SABI Interface */
  	ifaceP = (readw(samsung->sabi + config->header_offsets.data_segment) & 0x0ffff) << 4;
  	ifaceP += readw(samsung->sabi + config->header_offsets.data_offset) & 0x0ffff;
  
  	if (debug)
  		samsung_sabi_infos(samsung, loca, ifaceP);
  
  	samsung->sabi_iface = ioremap_nocache(ifaceP, 16);
  	if (!samsung->sabi_iface) {
  		pr_err("Can't remap %x\n", ifaceP);
  		ret = -EINVAL;
  		goto exit;
  	}
  
  	/* Turn on "Linux" mode in the BIOS */
  	if (commands->set_linux != 0xff) {
  		int retval = sabi_set_commandb(samsung,
  					       commands->set_linux, 0x81);
  		if (retval) {
  			pr_warn("Linux mode was not set!\n");
  			ret = -ENODEV;
  			goto exit;
  		}
  	}
  
  	/* Check for stepping quirk */
  	if (samsung->handle_backlight)
  		check_for_stepping_quirk(samsung);
  
  	pr_info("detected SABI interface: %s\n",
  		samsung->config->test_string);
  
  exit:
  	if (ret)
  		samsung_sabi_exit(samsung);
  
  	return ret;
  }
  
  static void samsung_platform_exit(struct samsung_laptop *samsung)
  {
  	if (samsung->platform_device) {
  		platform_device_unregister(samsung->platform_device);
  		samsung->platform_device = NULL;
  	}
  }
  
  static int __init samsung_platform_init(struct samsung_laptop *samsung)
  {
  	struct platform_device *pdev;
  
  	pdev = platform_device_register_simple("samsung", -1, NULL, 0);
  	if (IS_ERR(pdev))
  		return PTR_ERR(pdev);
  
  	samsung->platform_device = pdev;
  	platform_set_drvdata(samsung->platform_device, samsung);
  	return 0;
  }
  
  static struct samsung_quirks *quirks;
  
  static int __init samsung_dmi_matched(const struct dmi_system_id *d)
  {
  	quirks = d->driver_data;
  	return 0;
  }
  
  static struct dmi_system_id __initdata samsung_dmi_table[] = {
  	{
  		.matches = {
  			DMI_MATCH(DMI_SYS_VENDOR,
  					"SAMSUNG ELECTRONICS CO., LTD."),
  			DMI_MATCH(DMI_CHASSIS_TYPE, "8"), /* Portable */
  		},
  	},
  	{
  		.matches = {
  			DMI_MATCH(DMI_SYS_VENDOR,
  					"SAMSUNG ELECTRONICS CO., LTD."),
  			DMI_MATCH(DMI_CHASSIS_TYPE, "9"), /* Laptop */
  		},
  	},
  	{
  		.matches = {
  			DMI_MATCH(DMI_SYS_VENDOR,
  					"SAMSUNG ELECTRONICS CO., LTD."),
  			DMI_MATCH(DMI_CHASSIS_TYPE, "10"), /* Notebook */
  		},
  	},
  	{
  		.matches = {
  			DMI_MATCH(DMI_SYS_VENDOR,
  					"SAMSUNG ELECTRONICS CO., LTD."),
  			DMI_MATCH(DMI_CHASSIS_TYPE, "14"), /* Sub-Notebook */
  		},
  	},
  	/* DMI ids for laptops with bad Chassis Type */
  	{
  	  .ident = "R40/R41",
  	  .matches = {
  		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
  		DMI_MATCH(DMI_PRODUCT_NAME, "R40/R41"),
  		DMI_MATCH(DMI_BOARD_NAME, "R40/R41"),
  		},
  	},
  	/* Specific DMI ids for laptop with quirks */
  	{
  	 .callback = samsung_dmi_matched,
  	 .ident = "N150P",
  	 .matches = {
  		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
  		DMI_MATCH(DMI_PRODUCT_NAME, "N150P"),
  		DMI_MATCH(DMI_BOARD_NAME, "N150P"),
  		},
  	 .driver_data = &samsung_broken_acpi_video,
  	},
  	{
  	 .callback = samsung_dmi_matched,
  	 .ident = "N145P/N250P/N260P",
  	 .matches = {
  		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
  		DMI_MATCH(DMI_PRODUCT_NAME, "N145P/N250P/N260P"),
  		DMI_MATCH(DMI_BOARD_NAME, "N145P/N250P/N260P"),
  		},
  	 .driver_data = &samsung_broken_acpi_video,
  	},
  	{
  	 .callback = samsung_dmi_matched,
  	 .ident = "N150/N210/N220",
  	 .matches = {
  		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
  		DMI_MATCH(DMI_PRODUCT_NAME, "N150/N210/N220"),
  		DMI_MATCH(DMI_BOARD_NAME, "N150/N210/N220"),
  		},
  	 .driver_data = &samsung_broken_acpi_video,
  	},
  	{
  	 .callback = samsung_dmi_matched,
  	 .ident = "NF110/NF210/NF310",
  	 .matches = {
  		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
  		DMI_MATCH(DMI_PRODUCT_NAME, "NF110/NF210/NF310"),
  		DMI_MATCH(DMI_BOARD_NAME, "NF110/NF210/NF310"),
  		},
  	 .driver_data = &samsung_broken_acpi_video,
  	},
  	{
  	 .callback = samsung_dmi_matched,
  	 .ident = "X360",
  	 .matches = {
  		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
  		DMI_MATCH(DMI_PRODUCT_NAME, "X360"),
  		DMI_MATCH(DMI_BOARD_NAME, "X360"),
  		},
  	 .driver_data = &samsung_broken_acpi_video,
  	},
  	{
  	 .callback = samsung_dmi_matched,
  	 .ident = "N250P",
  	 .matches = {
  		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
  		DMI_MATCH(DMI_PRODUCT_NAME, "N250P"),
  		DMI_MATCH(DMI_BOARD_NAME, "N250P"),
  		},
  	 .driver_data = &samsung_broken_acpi_video,
  	},
  	{ },
  };
  MODULE_DEVICE_TABLE(dmi, samsung_dmi_table);
  
  static struct platform_device *samsung_platform_device;
  
  static int __init samsung_init(void)
  {
  	struct samsung_laptop *samsung;
  	int ret;
  
  	if (efi_enabled(EFI_BOOT))
  		return -ENODEV;
  
  	quirks = &samsung_unknown;
  	if (!force && !dmi_check_system(samsung_dmi_table))
  		return -ENODEV;
  
  	samsung = kzalloc(sizeof(*samsung), GFP_KERNEL);
  	if (!samsung)
  		return -ENOMEM;
  
  	mutex_init(&samsung->sabi_mutex);
  	samsung->handle_backlight = true;
  	samsung->quirks = quirks;
  
  
  #ifdef CONFIG_ACPI
  	if (samsung->quirks->broken_acpi_video)
  		acpi_video_dmi_promote_vendor();
  
  	/* Don't handle backlight here if the acpi video already handle it */
  	if (acpi_video_backlight_support()) {
  		samsung->handle_backlight = false;
  	} else if (samsung->quirks->broken_acpi_video) {
  		pr_info("Disabling ACPI video driver\n");
  		acpi_video_unregister();
  	}
  #endif
  
  	ret = samsung_platform_init(samsung);
  	if (ret)
  		goto error_platform;
  
  	ret = samsung_sabi_init(samsung);
  	if (ret)
  		goto error_sabi;
  
  #ifdef CONFIG_ACPI
  	/* Only log that if we are really on a sabi platform */
  	if (acpi_video_backlight_support())
  		pr_info("Backlight controlled by ACPI video driver\n");
  #endif
  
  	ret = samsung_sysfs_init(samsung);
  	if (ret)
  		goto error_sysfs;
  
  	ret = samsung_backlight_init(samsung);
  	if (ret)
  		goto error_backlight;
  
  	ret = samsung_rfkill_init(samsung);
  	if (ret)
  		goto error_rfkill;
  
  	ret = samsung_leds_init(samsung);
  	if (ret)
  		goto error_leds;
  
  	ret = samsung_debugfs_init(samsung);
  	if (ret)
  		goto error_debugfs;
  
  	samsung_platform_device = samsung->platform_device;
  	return ret;
  
  error_debugfs:
  	samsung_leds_exit(samsung);
  error_leds:
  	samsung_rfkill_exit(samsung);
  error_rfkill:
  	samsung_backlight_exit(samsung);
  error_backlight:
  	samsung_sysfs_exit(samsung);
  error_sysfs:
  	samsung_sabi_exit(samsung);
  error_sabi:
  	samsung_platform_exit(samsung);
  error_platform:
  	kfree(samsung);
  	return ret;
  }
  
  static void __exit samsung_exit(void)
  {
  	struct samsung_laptop *samsung;
  
  	samsung = platform_get_drvdata(samsung_platform_device);
  
  	samsung_debugfs_exit(samsung);
  	samsung_leds_exit(samsung);
  	samsung_rfkill_exit(samsung);
  	samsung_backlight_exit(samsung);
  	samsung_sysfs_exit(samsung);
  	samsung_sabi_exit(samsung);
  	samsung_platform_exit(samsung);
  
  	kfree(samsung);
  	samsung_platform_device = NULL;
  }
  
  module_init(samsung_init);
  module_exit(samsung_exit);
  
  MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@suse.de>");
  MODULE_DESCRIPTION("Samsung Backlight driver");
  MODULE_LICENSE("GPL");
  