1/*
  2 * BGRT boot graphic support
  3 * Authors: Matthew Garrett, Josh Triplett <josh@joshtriplett.org>
  4 * Copyright 2012 Red Hat, Inc <mjg@redhat.com>
  5 * Copyright 2012 Intel Corporation
  6 *
  7 * This program is free software; you can redistribute it and/or modify
  8 * it under the terms of the GNU General Public License version 2 as
  9 * published by the Free Software Foundation.
 10 */
 11
 12#include <linux/kernel.h>
 13#include <linux/init.h>
 14#include <linux/device.h>
 15#include <linux/sysfs.h>
 16#include <linux/efi-bgrt.h>
 17
 18static struct kobject *bgrt_kobj;
 19
 20static ssize_t show_version(struct device *dev,
 21			    struct device_attribute *attr, char *buf)
 22{
 23	return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->version);
 24}
 25static DEVICE_ATTR(version, S_IRUGO, show_version, NULL);
 26
 27static ssize_t show_status(struct device *dev,
 28			   struct device_attribute *attr, char *buf)
 29{
 30	return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->status);
 31}
 32static DEVICE_ATTR(status, S_IRUGO, show_status, NULL);
 33
 34static ssize_t show_type(struct device *dev,
 35			 struct device_attribute *attr, char *buf)
 36{
 37	return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->image_type);
 38}
 39static DEVICE_ATTR(type, S_IRUGO, show_type, NULL);
 40
 41static ssize_t show_xoffset(struct device *dev,
 42			    struct device_attribute *attr, char *buf)
 43{
 44	return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->image_offset_x);
 45}
 46static DEVICE_ATTR(xoffset, S_IRUGO, show_xoffset, NULL);
 47
 48static ssize_t show_yoffset(struct device *dev,
 49			    struct device_attribute *attr, char *buf)
 50{
 51	return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->image_offset_y);
 52}
 53static DEVICE_ATTR(yoffset, S_IRUGO, show_yoffset, NULL);
 54
 55static ssize_t image_read(struct file *file, struct kobject *kobj,
 56	       struct bin_attribute *attr, char *buf, loff_t off, size_t count)
 57{
 58	memcpy(buf, attr->private + off, count);
 59	return count;
 60}
 61
 62static BIN_ATTR_RO(image, 0);	/* size gets filled in later */
 63
 64static struct attribute *bgrt_attributes[] = {
 65	&dev_attr_version.attr,
 66	&dev_attr_status.attr,
 67	&dev_attr_type.attr,
 68	&dev_attr_xoffset.attr,
 69	&dev_attr_yoffset.attr,
 70	NULL,
 71};
 72
 73static struct bin_attribute *bgrt_bin_attributes[] = {
 74	&bin_attr_image,
 75	NULL,
 76};
 77
 78static struct attribute_group bgrt_attribute_group = {
 79	.attrs = bgrt_attributes,
 80	.bin_attrs = bgrt_bin_attributes,
 81};
 82
 83static int __init bgrt_init(void)
 84{
 85	int ret;
 86
 87	if (!bgrt_image)
 88		return -ENODEV;
 89
 90	bin_attr_image.private = bgrt_image;
 91	bin_attr_image.size = bgrt_image_size;
 92
 93	bgrt_kobj = kobject_create_and_add("bgrt", acpi_kobj);
 94	if (!bgrt_kobj)
 95		return -EINVAL;
 96
 97	ret = sysfs_create_group(bgrt_kobj, &bgrt_attribute_group);
 98	if (ret)
 99		goto out_kobject;
100
101	return 0;
102
103out_kobject:
104	kobject_put(bgrt_kobj);
105	return ret;
106}
107device_initcall(bgrt_init);