// SPDX-License-Identifier: GPL-2.0-only

  /*

   * BGRT boot graphic support
   * Authors: Matthew Garrett, Josh Triplett <josh@joshtriplett.org>

   * Copyright 2012 Red Hat, Inc <mjg@redhat.com>

   * Copyright 2012 Intel Corporation

   */
  
  #include <linux/kernel.h>

  #include <linux/init.h>
  #include <linux/device.h>
  #include <linux/sysfs.h>

  #include <linux/efi-bgrt.h>

  static void *bgrt_image;

  static struct kobject *bgrt_kobj;

  static ssize_t show_version(struct device *dev,
  			    struct device_attribute *attr, char *buf)
  {

  	return snprintf(buf, PAGE_SIZE, "%d
  ", bgrt_tab.version);

  }
  static DEVICE_ATTR(version, S_IRUGO, show_version, NULL);
  
  static ssize_t show_status(struct device *dev,
  			   struct device_attribute *attr, char *buf)
  {

  	return snprintf(buf, PAGE_SIZE, "%d
  ", bgrt_tab.status);

  }
  static DEVICE_ATTR(status, S_IRUGO, show_status, NULL);
  
  static ssize_t show_type(struct device *dev,
  			 struct device_attribute *attr, char *buf)
  {

  	return snprintf(buf, PAGE_SIZE, "%d
  ", bgrt_tab.image_type);

  }
  static DEVICE_ATTR(type, S_IRUGO, show_type, NULL);
  
  static ssize_t show_xoffset(struct device *dev,
  			    struct device_attribute *attr, char *buf)
  {

  	return snprintf(buf, PAGE_SIZE, "%d
  ", bgrt_tab.image_offset_x);

  }
  static DEVICE_ATTR(xoffset, S_IRUGO, show_xoffset, NULL);
  
  static ssize_t show_yoffset(struct device *dev,
  			    struct device_attribute *attr, char *buf)
  {

  	return snprintf(buf, PAGE_SIZE, "%d
  ", bgrt_tab.image_offset_y);

  }
  static DEVICE_ATTR(yoffset, S_IRUGO, show_yoffset, NULL);

  static ssize_t image_read(struct file *file, struct kobject *kobj,

  	       struct bin_attribute *attr, char *buf, loff_t off, size_t count)
  {

  	memcpy(buf, attr->private + off, count);

  	return count;
  }

  static BIN_ATTR_RO(image, 0);	/* size gets filled in later */

  
  static struct attribute *bgrt_attributes[] = {
  	&dev_attr_version.attr,
  	&dev_attr_status.attr,
  	&dev_attr_type.attr,
  	&dev_attr_xoffset.attr,
  	&dev_attr_yoffset.attr,
  	NULL,
  };

  static struct bin_attribute *bgrt_bin_attributes[] = {
  	&bin_attr_image,
  	NULL,
  };

  static const struct attribute_group bgrt_attribute_group = {

  	.attrs = bgrt_attributes,

  	.bin_attrs = bgrt_bin_attributes,

  };

  int __init acpi_parse_bgrt(struct acpi_table_header *table)
  {
  	efi_bgrt_init(table);
  	return 0;
  }

  static int __init bgrt_init(void)
  {

  	int ret;

  	if (!bgrt_tab.image_address)

  		return -ENODEV;

  	bgrt_image = memremap(bgrt_tab.image_address, bgrt_image_size,
  			      MEMREMAP_WB);
  	if (!bgrt_image) {
  		pr_notice("Ignoring BGRT: failed to map image memory
  ");
  		return -ENOMEM;
  	}

  	bin_attr_image.private = bgrt_image;
  	bin_attr_image.size = bgrt_image_size;

  
  	bgrt_kobj = kobject_create_and_add("bgrt", acpi_kobj);

  	if (!bgrt_kobj) {
  		ret = -EINVAL;
  		goto out_memmap;
  	}

  
  	ret = sysfs_create_group(bgrt_kobj, &bgrt_attribute_group);
  	if (ret)
  		goto out_kobject;

  	return 0;

  out_kobject:
  	kobject_put(bgrt_kobj);

  out_memmap:
  	memunmap(bgrt_image);

  	return ret;
  }

  device_initcall(bgrt_init);