aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/acpi/bgrt.c
blob: 8cf6c46e99fb538b320b7e63131269ef78accaae (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
/*
 * 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");