/*
   * linux/drivers/firmware/edd.c
   *  Copyright (C) 2002, 2003, 2004 Dell Inc.
   *  by Matt Domsch <Matt_Domsch@dell.com>
   *  disk signature by Matt Domsch, Andrew Wilks, and Sandeep K. Shandilya
   *  legacy CHS by Patrick J. LoPresti <patl@users.sourceforge.net>
   *
   * BIOS Enhanced Disk Drive Services (EDD)
   * conformant to T13 Committee www.t13.org
   *   projects 1572D, 1484D, 1386D, 1226DT
   *
   * This code takes information provided by BIOS EDD calls
   * fn41 - Check Extensions Present and
   * fn48 - Get Device Parameters with EDD extensions
   * made in setup.S, copied to safe structures in setup.c,
   * and presents it in sysfs.
   *
   * Please see http://linux.dell.com/edd/results.html for
   * the list of BIOSs which have been reported to implement EDD.
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License v2.0 as published by
   * the Free Software Foundation
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   */
  
  #include <linux/module.h>
  #include <linux/string.h>
  #include <linux/types.h>
  #include <linux/init.h>
  #include <linux/stat.h>
  #include <linux/err.h>
  #include <linux/ctype.h>
  #include <linux/slab.h>
  #include <linux/limits.h>
  #include <linux/device.h>
  #include <linux/pci.h>
  #include <linux/blkdev.h>
  #include <linux/edd.h>
  
  #define EDD_VERSION "0.16"
  #define EDD_DATE    "2004-Jun-25"
  
  MODULE_AUTHOR("Matt Domsch <Matt_Domsch@Dell.com>");
  MODULE_DESCRIPTION("sysfs interface to BIOS EDD information");
  MODULE_LICENSE("GPL");
  MODULE_VERSION(EDD_VERSION);
  
  #define left (PAGE_SIZE - (p - buf) - 1)
  
  struct edd_device {
  	unsigned int index;
  	unsigned int mbr_signature;
  	struct edd_info *info;
  	struct kobject kobj;
  };
  
  struct edd_attribute {
  	struct attribute attr;
  	ssize_t(*show) (struct edd_device * edev, char *buf);
  	int (*test) (struct edd_device * edev);
  };
  
  /* forward declarations */
  static int edd_dev_is_type(struct edd_device *edev, const char *type);
  static struct pci_dev *edd_get_pci_dev(struct edd_device *edev);
  
  static struct edd_device *edd_devices[EDD_MBR_SIG_MAX];
  
  #define EDD_DEVICE_ATTR(_name,_mode,_show,_test) \
  struct edd_attribute edd_attr_##_name = { 	\
  	.attr = {.name = __stringify(_name), .mode = _mode },	\
  	.show	= _show,				\
  	.test	= _test,				\
  };
  
  static int
  edd_has_mbr_signature(struct edd_device *edev)
  {
  	return edev->index < min_t(unsigned char, edd.mbr_signature_nr, EDD_MBR_SIG_MAX);
  }
  
  static int
  edd_has_edd_info(struct edd_device *edev)
  {
  	return edev->index < min_t(unsigned char, edd.edd_info_nr, EDDMAXNR);
  }
  
  static inline struct edd_info *
  edd_dev_get_info(struct edd_device *edev)
  {
  	return edev->info;
  }
  
  static inline void
  edd_dev_set_info(struct edd_device *edev, int i)
  {
  	edev->index = i;
  	if (edd_has_mbr_signature(edev))
  		edev->mbr_signature = edd.mbr_signature[i];
  	if (edd_has_edd_info(edev))
  		edev->info = &edd.edd_info[i];
  }
  
  #define to_edd_attr(_attr) container_of(_attr,struct edd_attribute,attr)
  #define to_edd_device(obj) container_of(obj,struct edd_device,kobj)
  
  static ssize_t
  edd_attr_show(struct kobject * kobj, struct attribute *attr, char *buf)
  {
  	struct edd_device *dev = to_edd_device(kobj);
  	struct edd_attribute *edd_attr = to_edd_attr(attr);
  	ssize_t ret = -EIO;
  
  	if (edd_attr->show)
  		ret = edd_attr->show(dev, buf);
  	return ret;
  }
  
  static const struct sysfs_ops edd_attr_ops = {
  	.show = edd_attr_show,
  };
  
  static ssize_t
  edd_show_host_bus(struct edd_device *edev, char *buf)
  {
  	struct edd_info *info;
  	char *p = buf;
  	int i;
  
  	if (!edev)
  		return -EINVAL;
  	info = edd_dev_get_info(edev);
  	if (!info || !buf)
  		return -EINVAL;
  
  	for (i = 0; i < 4; i++) {
  		if (isprint(info->params.host_bus_type[i])) {
  			p += scnprintf(p, left, "%c", info->params.host_bus_type[i]);
  		} else {
  			p += scnprintf(p, left, " ");
  		}
  	}
  
  	if (!strncmp(info->params.host_bus_type, "ISA", 3)) {
  		p += scnprintf(p, left, "\tbase_address: %x
  ",
  			     info->params.interface_path.isa.base_address);
  	} else if (!strncmp(info->params.host_bus_type, "PCIX", 4) ||
  		   !strncmp(info->params.host_bus_type, "PCI", 3) ||
  		   !strncmp(info->params.host_bus_type, "XPRS", 4)) {
  		p += scnprintf(p, left,
  			     "\t%02x:%02x.%d  channel: %u
  ",
  			     info->params.interface_path.pci.bus,
  			     info->params.interface_path.pci.slot,
  			     info->params.interface_path.pci.function,
  			     info->params.interface_path.pci.channel);
  	} else if (!strncmp(info->params.host_bus_type, "IBND", 4) ||
  		   !strncmp(info->params.host_bus_type, "HTPT", 4)) {
  		p += scnprintf(p, left,
  			     "\tTBD: %llx
  ",
  			     info->params.interface_path.ibnd.reserved);
  
  	} else {
  		p += scnprintf(p, left, "\tunknown: %llx
  ",
  			     info->params.interface_path.unknown.reserved);
  	}
  	return (p - buf);
  }
  
  static ssize_t
  edd_show_interface(struct edd_device *edev, char *buf)
  {
  	struct edd_info *info;
  	char *p = buf;
  	int i;
  
  	if (!edev)
  		return -EINVAL;
  	info = edd_dev_get_info(edev);
  	if (!info || !buf)
  		return -EINVAL;
  
  	for (i = 0; i < 8; i++) {
  		if (isprint(info->params.interface_type[i])) {
  			p += scnprintf(p, left, "%c", info->params.interface_type[i]);
  		} else {
  			p += scnprintf(p, left, " ");
  		}
  	}
  	if (!strncmp(info->params.interface_type, "ATAPI", 5)) {
  		p += scnprintf(p, left, "\tdevice: %u  lun: %u
  ",
  			     info->params.device_path.atapi.device,
  			     info->params.device_path.atapi.lun);
  	} else if (!strncmp(info->params.interface_type, "ATA", 3)) {
  		p += scnprintf(p, left, "\tdevice: %u
  ",
  			     info->params.device_path.ata.device);
  	} else if (!strncmp(info->params.interface_type, "SCSI", 4)) {
  		p += scnprintf(p, left, "\tid: %u  lun: %llu
  ",
  			     info->params.device_path.scsi.id,
  			     info->params.device_path.scsi.lun);
  	} else if (!strncmp(info->params.interface_type, "USB", 3)) {
  		p += scnprintf(p, left, "\tserial_number: %llx
  ",
  			     info->params.device_path.usb.serial_number);
  	} else if (!strncmp(info->params.interface_type, "1394", 4)) {
  		p += scnprintf(p, left, "\teui: %llx
  ",
  			     info->params.device_path.i1394.eui);
  	} else if (!strncmp(info->params.interface_type, "FIBRE", 5)) {
  		p += scnprintf(p, left, "\twwid: %llx lun: %llx
  ",
  			     info->params.device_path.fibre.wwid,
  			     info->params.device_path.fibre.lun);
  	} else if (!strncmp(info->params.interface_type, "I2O", 3)) {
  		p += scnprintf(p, left, "\tidentity_tag: %llx
  ",
  			     info->params.device_path.i2o.identity_tag);
  	} else if (!strncmp(info->params.interface_type, "RAID", 4)) {
  		p += scnprintf(p, left, "\tidentity_tag: %x
  ",
  			     info->params.device_path.raid.array_number);
  	} else if (!strncmp(info->params.interface_type, "SATA", 4)) {
  		p += scnprintf(p, left, "\tdevice: %u
  ",
  			     info->params.device_path.sata.device);
  	} else {
  		p += scnprintf(p, left, "\tunknown: %llx %llx
  ",
  			     info->params.device_path.unknown.reserved1,
  			     info->params.device_path.unknown.reserved2);
  	}
  
  	return (p - buf);
  }
  
  /**
   * edd_show_raw_data() - copies raw data to buffer for userspace to parse
   * @edev: target edd_device
   * @buf: output buffer
   *
   * Returns: number of bytes written, or -EINVAL on failure
   */
  static ssize_t
  edd_show_raw_data(struct edd_device *edev, char *buf)
  {
  	struct edd_info *info;
  	ssize_t len = sizeof (info->params);
  	if (!edev)
  		return -EINVAL;
  	info = edd_dev_get_info(edev);
  	if (!info || !buf)
  		return -EINVAL;
  
  	if (!(info->params.key == 0xBEDD || info->params.key == 0xDDBE))
  		len = info->params.length;
  
  	/* In case of buggy BIOSs */
  	if (len > (sizeof(info->params)))
  		len = sizeof(info->params);
  
  	memcpy(buf, &info->params, len);
  	return len;
  }
  
  static ssize_t
  edd_show_version(struct edd_device *edev, char *buf)
  {
  	struct edd_info *info;
  	char *p = buf;
  	if (!edev)
  		return -EINVAL;
  	info = edd_dev_get_info(edev);
  	if (!info || !buf)
  		return -EINVAL;
  
  	p += scnprintf(p, left, "0x%02x
  ", info->version);
  	return (p - buf);
  }
  
  static ssize_t
  edd_show_mbr_signature(struct edd_device *edev, char *buf)
  {
  	char *p = buf;
  	p += scnprintf(p, left, "0x%08x
  ", edev->mbr_signature);
  	return (p - buf);
  }
  
  static ssize_t
  edd_show_extensions(struct edd_device *edev, char *buf)
  {
  	struct edd_info *info;
  	char *p = buf;
  	if (!edev)
  		return -EINVAL;
  	info = edd_dev_get_info(edev);
  	if (!info || !buf)
  		return -EINVAL;
  
  	if (info->interface_support & EDD_EXT_FIXED_DISK_ACCESS) {
  		p += scnprintf(p, left, "Fixed disk access
  ");
  	}
  	if (info->interface_support & EDD_EXT_DEVICE_LOCKING_AND_EJECTING) {
  		p += scnprintf(p, left, "Device locking and ejecting
  ");
  	}
  	if (info->interface_support & EDD_EXT_ENHANCED_DISK_DRIVE_SUPPORT) {
  		p += scnprintf(p, left, "Enhanced Disk Drive support
  ");
  	}
  	if (info->interface_support & EDD_EXT_64BIT_EXTENSIONS) {
  		p += scnprintf(p, left, "64-bit extensions
  ");
  	}
  	return (p - buf);
  }
  
  static ssize_t
  edd_show_info_flags(struct edd_device *edev, char *buf)
  {
  	struct edd_info *info;
  	char *p = buf;
  	if (!edev)
  		return -EINVAL;
  	info = edd_dev_get_info(edev);
  	if (!info || !buf)
  		return -EINVAL;
  
  	if (info->params.info_flags & EDD_INFO_DMA_BOUNDARY_ERROR_TRANSPARENT)
  		p += scnprintf(p, left, "DMA boundary error transparent
  ");
  	if (info->params.info_flags & EDD_INFO_GEOMETRY_VALID)
  		p += scnprintf(p, left, "geometry valid
  ");
  	if (info->params.info_flags & EDD_INFO_REMOVABLE)
  		p += scnprintf(p, left, "removable
  ");
  	if (info->params.info_flags & EDD_INFO_WRITE_VERIFY)
  		p += scnprintf(p, left, "write verify
  ");
  	if (info->params.info_flags & EDD_INFO_MEDIA_CHANGE_NOTIFICATION)
  		p += scnprintf(p, left, "media change notification
  ");
  	if (info->params.info_flags & EDD_INFO_LOCKABLE)
  		p += scnprintf(p, left, "lockable
  ");
  	if (info->params.info_flags & EDD_INFO_NO_MEDIA_PRESENT)
  		p += scnprintf(p, left, "no media present
  ");
  	if (info->params.info_flags & EDD_INFO_USE_INT13_FN50)
  		p += scnprintf(p, left, "use int13 fn50
  ");
  	return (p - buf);
  }
  
  static ssize_t
  edd_show_legacy_max_cylinder(struct edd_device *edev, char *buf)
  {
  	struct edd_info *info;
  	char *p = buf;
  	if (!edev)
  		return -EINVAL;
  	info = edd_dev_get_info(edev);
  	if (!info || !buf)
  		return -EINVAL;
  
  	p += snprintf(p, left, "%u
  ", info->legacy_max_cylinder);
  	return (p - buf);
  }
  
  static ssize_t
  edd_show_legacy_max_head(struct edd_device *edev, char *buf)
  {
  	struct edd_info *info;
  	char *p = buf;
  	if (!edev)
  		return -EINVAL;
  	info = edd_dev_get_info(edev);
  	if (!info || !buf)
  		return -EINVAL;
  
  	p += snprintf(p, left, "%u
  ", info->legacy_max_head);
  	return (p - buf);
  }
  
  static ssize_t
  edd_show_legacy_sectors_per_track(struct edd_device *edev, char *buf)
  {
  	struct edd_info *info;
  	char *p = buf;
  	if (!edev)
  		return -EINVAL;
  	info = edd_dev_get_info(edev);
  	if (!info || !buf)
  		return -EINVAL;
  
  	p += snprintf(p, left, "%u
  ", info->legacy_sectors_per_track);
  	return (p - buf);
  }
  
  static ssize_t
  edd_show_default_cylinders(struct edd_device *edev, char *buf)
  {
  	struct edd_info *info;
  	char *p = buf;
  	if (!edev)
  		return -EINVAL;
  	info = edd_dev_get_info(edev);
  	if (!info || !buf)
  		return -EINVAL;
  
  	p += scnprintf(p, left, "%u
  ", info->params.num_default_cylinders);
  	return (p - buf);
  }
  
  static ssize_t
  edd_show_default_heads(struct edd_device *edev, char *buf)
  {
  	struct edd_info *info;
  	char *p = buf;
  	if (!edev)
  		return -EINVAL;
  	info = edd_dev_get_info(edev);
  	if (!info || !buf)
  		return -EINVAL;
  
  	p += scnprintf(p, left, "%u
  ", info->params.num_default_heads);
  	return (p - buf);
  }
  
  static ssize_t
  edd_show_default_sectors_per_track(struct edd_device *edev, char *buf)
  {
  	struct edd_info *info;
  	char *p = buf;
  	if (!edev)
  		return -EINVAL;
  	info = edd_dev_get_info(edev);
  	if (!info || !buf)
  		return -EINVAL;
  
  	p += scnprintf(p, left, "%u
  ", info->params.sectors_per_track);
  	return (p - buf);
  }
  
  static ssize_t
  edd_show_sectors(struct edd_device *edev, char *buf)
  {
  	struct edd_info *info;
  	char *p = buf;
  	if (!edev)
  		return -EINVAL;
  	info = edd_dev_get_info(edev);
  	if (!info || !buf)
  		return -EINVAL;
  
  	p += scnprintf(p, left, "%llu
  ", info->params.number_of_sectors);
  	return (p - buf);
  }
  
  
  /*
   * Some device instances may not have all the above attributes,
   * or the attribute values may be meaningless (i.e. if
   * the device is < EDD 3.0, it won't have host_bus and interface
   * information), so don't bother making files for them.  Likewise
   * if the default_{cylinders,heads,sectors_per_track} values
   * are zero, the BIOS doesn't provide sane values, don't bother
   * creating files for them either.
   */
  
  static int
  edd_has_legacy_max_cylinder(struct edd_device *edev)
  {
  	struct edd_info *info;
  	if (!edev)
  		return 0;
  	info = edd_dev_get_info(edev);
  	if (!info)
  		return 0;
  	return info->legacy_max_cylinder > 0;
  }
  
  static int
  edd_has_legacy_max_head(struct edd_device *edev)
  {
  	struct edd_info *info;
  	if (!edev)
  		return 0;
  	info = edd_dev_get_info(edev);
  	if (!info)
  		return 0;
  	return info->legacy_max_head > 0;
  }
  
  static int
  edd_has_legacy_sectors_per_track(struct edd_device *edev)
  {
  	struct edd_info *info;
  	if (!edev)
  		return 0;
  	info = edd_dev_get_info(edev);
  	if (!info)
  		return 0;
  	return info->legacy_sectors_per_track > 0;
  }
  
  static int
  edd_has_default_cylinders(struct edd_device *edev)
  {
  	struct edd_info *info;
  	if (!edev)
  		return 0;
  	info = edd_dev_get_info(edev);
  	if (!info)
  		return 0;
  	return info->params.num_default_cylinders > 0;
  }
  
  static int
  edd_has_default_heads(struct edd_device *edev)
  {
  	struct edd_info *info;
  	if (!edev)
  		return 0;
  	info = edd_dev_get_info(edev);
  	if (!info)
  		return 0;
  	return info->params.num_default_heads > 0;
  }
  
  static int
  edd_has_default_sectors_per_track(struct edd_device *edev)
  {
  	struct edd_info *info;
  	if (!edev)
  		return 0;
  	info = edd_dev_get_info(edev);
  	if (!info)
  		return 0;
  	return info->params.sectors_per_track > 0;
  }
  
  static int
  edd_has_edd30(struct edd_device *edev)
  {
  	struct edd_info *info;
  	int i;
  	u8 csum = 0;
  
  	if (!edev)
  		return 0;
  	info = edd_dev_get_info(edev);
  	if (!info)
  		return 0;
  
  	if (!(info->params.key == 0xBEDD || info->params.key == 0xDDBE)) {
  		return 0;
  	}
  
  
  	/* We support only T13 spec */
  	if (info->params.device_path_info_length != 44)
  		return 0;
  
  	for (i = 30; i < info->params.device_path_info_length + 30; i++)
  		csum += *(((u8 *)&info->params) + i);
  
  	if (csum)
  		return 0;
  
  	return 1;
  }
  
  
  static EDD_DEVICE_ATTR(raw_data, 0444, edd_show_raw_data, edd_has_edd_info);
  static EDD_DEVICE_ATTR(version, 0444, edd_show_version, edd_has_edd_info);
  static EDD_DEVICE_ATTR(extensions, 0444, edd_show_extensions, edd_has_edd_info);
  static EDD_DEVICE_ATTR(info_flags, 0444, edd_show_info_flags, edd_has_edd_info);
  static EDD_DEVICE_ATTR(sectors, 0444, edd_show_sectors, edd_has_edd_info);
  static EDD_DEVICE_ATTR(legacy_max_cylinder, 0444,
                         edd_show_legacy_max_cylinder,
  		       edd_has_legacy_max_cylinder);
  static EDD_DEVICE_ATTR(legacy_max_head, 0444, edd_show_legacy_max_head,
  		       edd_has_legacy_max_head);
  static EDD_DEVICE_ATTR(legacy_sectors_per_track, 0444,
                         edd_show_legacy_sectors_per_track,
  		       edd_has_legacy_sectors_per_track);
  static EDD_DEVICE_ATTR(default_cylinders, 0444, edd_show_default_cylinders,
  		       edd_has_default_cylinders);
  static EDD_DEVICE_ATTR(default_heads, 0444, edd_show_default_heads,
  		       edd_has_default_heads);
  static EDD_DEVICE_ATTR(default_sectors_per_track, 0444,
  		       edd_show_default_sectors_per_track,
  		       edd_has_default_sectors_per_track);
  static EDD_DEVICE_ATTR(interface, 0444, edd_show_interface, edd_has_edd30);
  static EDD_DEVICE_ATTR(host_bus, 0444, edd_show_host_bus, edd_has_edd30);
  static EDD_DEVICE_ATTR(mbr_signature, 0444, edd_show_mbr_signature, edd_has_mbr_signature);
  
  
  /* These are default attributes that are added for every edd
   * device discovered.  There are none.
   */
  static struct attribute * def_attrs[] = {
  	NULL,
  };
  
  /* These attributes are conditional and only added for some devices. */
  static struct edd_attribute * edd_attrs[] = {
  	&edd_attr_raw_data,
  	&edd_attr_version,
  	&edd_attr_extensions,
  	&edd_attr_info_flags,
  	&edd_attr_sectors,
  	&edd_attr_legacy_max_cylinder,
  	&edd_attr_legacy_max_head,
  	&edd_attr_legacy_sectors_per_track,
  	&edd_attr_default_cylinders,
  	&edd_attr_default_heads,
  	&edd_attr_default_sectors_per_track,
  	&edd_attr_interface,
  	&edd_attr_host_bus,
  	&edd_attr_mbr_signature,
  	NULL,
  };
  
  /**
   *	edd_release - free edd structure
   *	@kobj:	kobject of edd structure
   *
   *	This is called when the refcount of the edd structure
   *	reaches 0. This should happen right after we unregister,
   *	but just in case, we use the release callback anyway.
   */
  
  static void edd_release(struct kobject * kobj)
  {
  	struct edd_device * dev = to_edd_device(kobj);
  	kfree(dev);
  }
  
  static struct kobj_type edd_ktype = {
  	.release	= edd_release,
  	.sysfs_ops	= &edd_attr_ops,
  	.default_attrs	= def_attrs,
  };
  
  static struct kset *edd_kset;
  
  
  /**
   * edd_dev_is_type() - is this EDD device a 'type' device?
   * @edev: target edd_device
   * @type: a host bus or interface identifier string per the EDD spec
   *
   * Returns 1 (TRUE) if it is a 'type' device, 0 otherwise.
   */
  static int
  edd_dev_is_type(struct edd_device *edev, const char *type)
  {
  	struct edd_info *info;
  	if (!edev)
  		return 0;
  	info = edd_dev_get_info(edev);
  
  	if (type && info) {
  		if (!strncmp(info->params.host_bus_type, type, strlen(type)) ||
  		    !strncmp(info->params.interface_type, type, strlen(type)))
  			return 1;
  	}
  	return 0;
  }
  
  /**
   * edd_get_pci_dev() - finds pci_dev that matches edev
   * @edev: edd_device
   *
   * Returns pci_dev if found, or NULL
   */
  static struct pci_dev *
  edd_get_pci_dev(struct edd_device *edev)
  {
  	struct edd_info *info = edd_dev_get_info(edev);
  
  	if (edd_dev_is_type(edev, "PCI") || edd_dev_is_type(edev, "XPRS")) {
  		return pci_get_bus_and_slot(info->params.interface_path.pci.bus,
  				     PCI_DEVFN(info->params.interface_path.pci.slot,
  					       info->params.interface_path.pci.
  					       function));
  	}
  	return NULL;
  }
  
  static int
  edd_create_symlink_to_pcidev(struct edd_device *edev)
  {
  
  	struct pci_dev *pci_dev = edd_get_pci_dev(edev);
  	int ret;
  	if (!pci_dev)
  		return 1;
  	ret = sysfs_create_link(&edev->kobj,&pci_dev->dev.kobj,"pci_dev");
  	pci_dev_put(pci_dev);
  	return ret;
  }
  
  static inline void
  edd_device_unregister(struct edd_device *edev)
  {
  	kobject_put(&edev->kobj);
  }
  
  static void edd_populate_dir(struct edd_device * edev)
  {
  	struct edd_attribute * attr;
  	int error = 0;
  	int i;
  
  	for (i = 0; (attr = edd_attrs[i]) && !error; i++) {
  		if (!attr->test ||
  		    (attr->test && attr->test(edev)))
  			error = sysfs_create_file(&edev->kobj,&attr->attr);
  	}
  
  	if (!error) {
  		edd_create_symlink_to_pcidev(edev);
  	}
  }
  
  static int
  edd_device_register(struct edd_device *edev, int i)
  {
  	int error;
  
  	if (!edev)
  		return 1;
  	edd_dev_set_info(edev, i);
  	edev->kobj.kset = edd_kset;
  	error = kobject_init_and_add(&edev->kobj, &edd_ktype, NULL,
  				     "int13_dev%02x", 0x80 + i);
  	if (!error) {
  		edd_populate_dir(edev);
  		kobject_uevent(&edev->kobj, KOBJ_ADD);
  	}
  	return error;
  }
  
  static inline int edd_num_devices(void)
  {
  	return max_t(unsigned char,
  		     min_t(unsigned char, EDD_MBR_SIG_MAX, edd.mbr_signature_nr),
  		     min_t(unsigned char, EDDMAXNR, edd.edd_info_nr));
  }
  
  /**
   * edd_init() - creates sysfs tree of EDD data
   */
  static int __init
  edd_init(void)
  {
  	int i;
  	int rc=0;
  	struct edd_device *edev;
  
  	printk(KERN_INFO "BIOS EDD facility v%s %s, %d devices found
  ",
  	       EDD_VERSION, EDD_DATE, edd_num_devices());
  
  	if (!edd_num_devices()) {
  		printk(KERN_INFO "EDD information not available.
  ");
  		return -ENODEV;
  	}
  
  	edd_kset = kset_create_and_add("edd", NULL, firmware_kobj);
  	if (!edd_kset)
  		return -ENOMEM;
  
  	for (i = 0; i < edd_num_devices(); i++) {
  		edev = kzalloc(sizeof (*edev), GFP_KERNEL);
  		if (!edev) {
  			rc = -ENOMEM;
  			goto out;
  		}
  
  		rc = edd_device_register(edev, i);
  		if (rc) {
  			kfree(edev);
  			goto out;
  		}
  		edd_devices[i] = edev;
  	}
  
  	return 0;
  
  out:
  	while (--i >= 0)
  		edd_device_unregister(edd_devices[i]);
  	kset_unregister(edd_kset);
  	return rc;
  }
  
  static void __exit
  edd_exit(void)
  {
  	int i;
  	struct edd_device *edev;
  
  	for (i = 0; i < edd_num_devices(); i++) {
  		if ((edev = edd_devices[i]))
  			edd_device_unregister(edev);
  	}
  	kset_unregister(edd_kset);
  }
  
  late_initcall(edd_init);
  module_exit(edd_exit);