LXR linux/drivers/acpi/bgrt.c

   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);
 108