acrn-kernel/drivers/acpi/bgrt.c

102 lines
2.3 KiB
C

// 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;
#define BGRT_SHOW(_name, _member) \
static ssize_t _name##_show(struct kobject *kobj, \
struct kobj_attribute *attr, char *buf) \
{ \
return sysfs_emit(buf, "%d\n", bgrt_tab._member); \
} \
static struct kobj_attribute bgrt_attr_##_name = __ATTR_RO(_name)
BGRT_SHOW(version, version);
BGRT_SHOW(status, status);
BGRT_SHOW(type, image_type);
BGRT_SHOW(xoffset, image_offset_x);
BGRT_SHOW(yoffset, image_offset_y);
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[] = {
&bgrt_attr_version.attr,
&bgrt_attr_status.attr,
&bgrt_attr_type.attr,
&bgrt_attr_xoffset.attr,
&bgrt_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\n");
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);