linux/drivers/acpi/bgrt.c

176 lines
3.8 KiB
C

/*
* Copyright 2012 Red Hat, Inc <mjg@redhat.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/sysfs.h>
#include <acpi/acpi.h>
#include <acpi/acpi_bus.h>
static struct acpi_table_bgrt *bgrt_tab;
static struct kobject *bgrt_kobj;
struct bmp_header {
u16 id;
u32 size;
} __attribute ((packed));
static struct bmp_header bmp_header;
static ssize_t show_version(struct device *dev,
struct device_attribute *attr, char *buf)
{
return snprintf(buf, PAGE_SIZE, "%d\n", 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\n", 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\n", 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\n", 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\n", bgrt_tab->image_offset_y);
}
static DEVICE_ATTR(yoffset, S_IRUGO, show_yoffset, NULL);
static ssize_t show_image(struct file *file, struct kobject *kobj,
struct bin_attribute *attr, char *buf, loff_t off, size_t count)
{
int size = attr->size;
void __iomem *image = attr->private;
if (off >= size) {
count = 0;
} else {
if (off + count > size)
count = size - off;
memcpy_fromio(buf, image+off, count);
}
return count;
}
static struct bin_attribute image_attr = {
.attr = {
.name = "image",
.mode = S_IRUGO,
},
.read = show_image,
};
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 attribute_group bgrt_attribute_group = {
.attrs = bgrt_attributes,
};
static int __init bgrt_init(void)
{
acpi_status status;
int ret;
void __iomem *bgrt;
if (acpi_disabled)
return -ENODEV;
status = acpi_get_table("BGRT", 0,
(struct acpi_table_header **)&bgrt_tab);
if (ACPI_FAILURE(status))
return -ENODEV;
sysfs_bin_attr_init(&image_attr);
bgrt = ioremap(bgrt_tab->image_address, sizeof(struct bmp_header));
if (!bgrt) {
ret = -EINVAL;
goto out_err;
}
memcpy_fromio(&bmp_header, bgrt, sizeof(bmp_header));
image_attr.size = bmp_header.size;
iounmap(bgrt);
image_attr.private = ioremap(bgrt_tab->image_address, image_attr.size);
if (!image_attr.private) {
ret = -EINVAL;
goto out_err;
}
bgrt_kobj = kobject_create_and_add("bgrt", acpi_kobj);
if (!bgrt_kobj) {
ret = -EINVAL;
goto out_iounmap;
}
ret = sysfs_create_group(bgrt_kobj, &bgrt_attribute_group);
if (ret)
goto out_kobject;
ret = sysfs_create_bin_file(bgrt_kobj, &image_attr);
if (ret)
goto out_group;
return 0;
out_group:
sysfs_remove_group(bgrt_kobj, &bgrt_attribute_group);
out_kobject:
kobject_put(bgrt_kobj);
out_iounmap:
iounmap(image_attr.private);
out_err:
return ret;
}
static void __exit bgrt_exit(void)
{
iounmap(image_attr.private);
sysfs_remove_group(bgrt_kobj, &bgrt_attribute_group);
sysfs_remove_bin_file(bgrt_kobj, &image_attr);
}
module_init(bgrt_init);
module_exit(bgrt_exit);
MODULE_AUTHOR("Matthew Garrett");
MODULE_DESCRIPTION("BGRT boot graphic support");
MODULE_LICENSE("GPL");