xref: /OK3568_Linux_fs/kernel/drivers/acpi/bgrt.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * BGRT boot graphic support
4*4882a593Smuzhiyun  * Authors: Matthew Garrett, Josh Triplett <josh@joshtriplett.org>
5*4882a593Smuzhiyun  * Copyright 2012 Red Hat, Inc <mjg@redhat.com>
6*4882a593Smuzhiyun  * Copyright 2012 Intel Corporation
7*4882a593Smuzhiyun  */
8*4882a593Smuzhiyun 
9*4882a593Smuzhiyun #include <linux/kernel.h>
10*4882a593Smuzhiyun #include <linux/init.h>
11*4882a593Smuzhiyun #include <linux/device.h>
12*4882a593Smuzhiyun #include <linux/sysfs.h>
13*4882a593Smuzhiyun #include <linux/efi-bgrt.h>
14*4882a593Smuzhiyun 
15*4882a593Smuzhiyun static void *bgrt_image;
16*4882a593Smuzhiyun static struct kobject *bgrt_kobj;
17*4882a593Smuzhiyun 
18*4882a593Smuzhiyun #define BGRT_SHOW(_name, _member) \
19*4882a593Smuzhiyun 	static ssize_t _name##_show(struct kobject *kobj,			\
20*4882a593Smuzhiyun 				    struct kobj_attribute *attr, char *buf)	\
21*4882a593Smuzhiyun 	{									\
22*4882a593Smuzhiyun 		return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab._member);	\
23*4882a593Smuzhiyun 	}									\
24*4882a593Smuzhiyun 	struct kobj_attribute bgrt_attr_##_name = __ATTR_RO(_name)
25*4882a593Smuzhiyun 
26*4882a593Smuzhiyun BGRT_SHOW(version, version);
27*4882a593Smuzhiyun BGRT_SHOW(status, status);
28*4882a593Smuzhiyun BGRT_SHOW(type, image_type);
29*4882a593Smuzhiyun BGRT_SHOW(xoffset, image_offset_x);
30*4882a593Smuzhiyun BGRT_SHOW(yoffset, image_offset_y);
31*4882a593Smuzhiyun 
image_read(struct file * file,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)32*4882a593Smuzhiyun static ssize_t image_read(struct file *file, struct kobject *kobj,
33*4882a593Smuzhiyun 	       struct bin_attribute *attr, char *buf, loff_t off, size_t count)
34*4882a593Smuzhiyun {
35*4882a593Smuzhiyun 	memcpy(buf, attr->private + off, count);
36*4882a593Smuzhiyun 	return count;
37*4882a593Smuzhiyun }
38*4882a593Smuzhiyun 
39*4882a593Smuzhiyun static BIN_ATTR_RO(image, 0);	/* size gets filled in later */
40*4882a593Smuzhiyun 
41*4882a593Smuzhiyun static struct attribute *bgrt_attributes[] = {
42*4882a593Smuzhiyun 	&bgrt_attr_version.attr,
43*4882a593Smuzhiyun 	&bgrt_attr_status.attr,
44*4882a593Smuzhiyun 	&bgrt_attr_type.attr,
45*4882a593Smuzhiyun 	&bgrt_attr_xoffset.attr,
46*4882a593Smuzhiyun 	&bgrt_attr_yoffset.attr,
47*4882a593Smuzhiyun 	NULL,
48*4882a593Smuzhiyun };
49*4882a593Smuzhiyun 
50*4882a593Smuzhiyun static struct bin_attribute *bgrt_bin_attributes[] = {
51*4882a593Smuzhiyun 	&bin_attr_image,
52*4882a593Smuzhiyun 	NULL,
53*4882a593Smuzhiyun };
54*4882a593Smuzhiyun 
55*4882a593Smuzhiyun static const struct attribute_group bgrt_attribute_group = {
56*4882a593Smuzhiyun 	.attrs = bgrt_attributes,
57*4882a593Smuzhiyun 	.bin_attrs = bgrt_bin_attributes,
58*4882a593Smuzhiyun };
59*4882a593Smuzhiyun 
acpi_parse_bgrt(struct acpi_table_header * table)60*4882a593Smuzhiyun int __init acpi_parse_bgrt(struct acpi_table_header *table)
61*4882a593Smuzhiyun {
62*4882a593Smuzhiyun 	efi_bgrt_init(table);
63*4882a593Smuzhiyun 	return 0;
64*4882a593Smuzhiyun }
65*4882a593Smuzhiyun 
bgrt_init(void)66*4882a593Smuzhiyun static int __init bgrt_init(void)
67*4882a593Smuzhiyun {
68*4882a593Smuzhiyun 	int ret;
69*4882a593Smuzhiyun 
70*4882a593Smuzhiyun 	if (!bgrt_tab.image_address)
71*4882a593Smuzhiyun 		return -ENODEV;
72*4882a593Smuzhiyun 
73*4882a593Smuzhiyun 	bgrt_image = memremap(bgrt_tab.image_address, bgrt_image_size,
74*4882a593Smuzhiyun 			      MEMREMAP_WB);
75*4882a593Smuzhiyun 	if (!bgrt_image) {
76*4882a593Smuzhiyun 		pr_notice("Ignoring BGRT: failed to map image memory\n");
77*4882a593Smuzhiyun 		return -ENOMEM;
78*4882a593Smuzhiyun 	}
79*4882a593Smuzhiyun 
80*4882a593Smuzhiyun 	bin_attr_image.private = bgrt_image;
81*4882a593Smuzhiyun 	bin_attr_image.size = bgrt_image_size;
82*4882a593Smuzhiyun 
83*4882a593Smuzhiyun 	bgrt_kobj = kobject_create_and_add("bgrt", acpi_kobj);
84*4882a593Smuzhiyun 	if (!bgrt_kobj) {
85*4882a593Smuzhiyun 		ret = -EINVAL;
86*4882a593Smuzhiyun 		goto out_memmap;
87*4882a593Smuzhiyun 	}
88*4882a593Smuzhiyun 
89*4882a593Smuzhiyun 	ret = sysfs_create_group(bgrt_kobj, &bgrt_attribute_group);
90*4882a593Smuzhiyun 	if (ret)
91*4882a593Smuzhiyun 		goto out_kobject;
92*4882a593Smuzhiyun 
93*4882a593Smuzhiyun 	return 0;
94*4882a593Smuzhiyun 
95*4882a593Smuzhiyun out_kobject:
96*4882a593Smuzhiyun 	kobject_put(bgrt_kobj);
97*4882a593Smuzhiyun out_memmap:
98*4882a593Smuzhiyun 	memunmap(bgrt_image);
99*4882a593Smuzhiyun 	return ret;
100*4882a593Smuzhiyun }
101*4882a593Smuzhiyun device_initcall(bgrt_init);
102