xref: /linux/drivers/video/logo/logo.c (revision ca220141fa8ebae09765a242076b2b77338106b0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 /*
4  *  Linux logo to be displayed on boot
5  *
6  *  Copyright (C) 1996 Larry Ewing (lewing@isc.tamu.edu)
7  *  Copyright (C) 1996,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
8  *  Copyright (C) 2001 Greg Banks <gnb@alphalink.com.au>
9  *  Copyright (C) 2001 Jan-Benedict Glaw <jbglaw@lug-owl.de>
10  *  Copyright (C) 2003 Geert Uytterhoeven <geert@linux-m68k.org>
11  */
12 
13 #include <linux/linux_logo.h>
14 #include <linux/stddef.h>
15 #include <linux/module.h>
16 
17 #ifdef CONFIG_M68K
18 #include <asm/setup.h>
19 #endif
20 
21 static bool nologo;
22 module_param(nologo, bool, 0);
23 MODULE_PARM_DESC(nologo, "Disables startup logo");
24 
25 /*
26  * Logos are located in the initdata, and will be freed in kernel_init.
27  * Use late_init to mark the logos as freed to prevent any further use.
28  */
29 
30 static bool logos_freed;
31 
32 static int __init fb_logo_late_init(void)
33 {
34 	logos_freed = true;
35 	return 0;
36 }
37 
38 late_initcall_sync(fb_logo_late_init);
39 
40 /* logo's are marked __initdata. Use __ref to tell
41  * modpost that it is intended that this function uses data
42  * marked __initdata.
43  */
44 const struct linux_logo * __ref fb_find_logo(int depth)
45 {
46 	const struct linux_logo *logo = NULL;
47 
48 	if (nologo || logos_freed)
49 		return NULL;
50 
51 #ifdef CONFIG_LOGO_LINUX_MONO
52 	if (depth >= 1)
53 		logo = &logo_linux_mono;
54 #endif
55 
56 #ifdef CONFIG_LOGO_LINUX_VGA16
57 	if (depth >= 4)
58 		logo = &logo_linux_vga16;
59 #endif
60 
61 #ifdef CONFIG_LOGO_LINUX_CLUT224
62 	if (depth >= 8)
63 		logo = &logo_linux_clut224;
64 #endif
65 
66 	return logo;
67 }
68 EXPORT_SYMBOL_GPL(fb_find_logo);
69