xref: /openbmc/linux/drivers/acpi/bgrt.c (revision b6bec26c)
1 /*
2  * Copyright 2012 Red Hat, Inc <mjg@redhat.com>
3  * Copyright 2012 Intel Corporation
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/device.h>
14 #include <linux/sysfs.h>
15 #include <linux/efi-bgrt.h>
16 
17 static struct kobject *bgrt_kobj;
18 
19 static ssize_t show_version(struct device *dev,
20 			    struct device_attribute *attr, char *buf)
21 {
22 	return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->version);
23 }
24 static DEVICE_ATTR(version, S_IRUGO, show_version, NULL);
25 
26 static ssize_t show_status(struct device *dev,
27 			   struct device_attribute *attr, char *buf)
28 {
29 	return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->status);
30 }
31 static DEVICE_ATTR(status, S_IRUGO, show_status, NULL);
32 
33 static ssize_t show_type(struct device *dev,
34 			 struct device_attribute *attr, char *buf)
35 {
36 	return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->image_type);
37 }
38 static DEVICE_ATTR(type, S_IRUGO, show_type, NULL);
39 
40 static ssize_t show_xoffset(struct device *dev,
41 			    struct device_attribute *attr, char *buf)
42 {
43 	return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->image_offset_x);
44 }
45 static DEVICE_ATTR(xoffset, S_IRUGO, show_xoffset, NULL);
46 
47 static ssize_t show_yoffset(struct device *dev,
48 			    struct device_attribute *attr, char *buf)
49 {
50 	return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->image_offset_y);
51 }
52 static DEVICE_ATTR(yoffset, S_IRUGO, show_yoffset, NULL);
53 
54 static ssize_t show_image(struct file *file, struct kobject *kobj,
55 	       struct bin_attribute *attr, char *buf, loff_t off, size_t count)
56 {
57 	memcpy(buf, attr->private + off, count);
58 	return count;
59 }
60 
61 static struct bin_attribute image_attr = {
62 	.attr = {
63 		.name = "image",
64 		.mode = S_IRUGO,
65 	},
66 	.read = show_image,
67 };
68 
69 static struct attribute *bgrt_attributes[] = {
70 	&dev_attr_version.attr,
71 	&dev_attr_status.attr,
72 	&dev_attr_type.attr,
73 	&dev_attr_xoffset.attr,
74 	&dev_attr_yoffset.attr,
75 	NULL,
76 };
77 
78 static struct attribute_group bgrt_attribute_group = {
79 	.attrs = bgrt_attributes,
80 };
81 
82 static int __init bgrt_init(void)
83 {
84 	int ret;
85 
86 	if (!bgrt_image)
87 		return -ENODEV;
88 
89 	sysfs_bin_attr_init(&image_attr);
90 	image_attr.private = bgrt_image;
91 	image_attr.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 	ret = sysfs_create_bin_file(bgrt_kobj, &image_attr);
102 	if (ret)
103 		goto out_group;
104 
105 	return 0;
106 
107 out_group:
108 	sysfs_remove_group(bgrt_kobj, &bgrt_attribute_group);
109 out_kobject:
110 	kobject_put(bgrt_kobj);
111 	return ret;
112 }
113 
114 module_init(bgrt_init);
115 
116 MODULE_AUTHOR("Matthew Garrett, Josh Triplett <josh@joshtriplett.org>");
117 MODULE_DESCRIPTION("BGRT boot graphic support");
118 MODULE_LICENSE("GPL");
119