xref: /openbmc/linux/drivers/acpi/acpica/utuuid.c (revision 842ed298)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: utuuid -- UUID support functions
5  *
6  * Copyright (C) 2000 - 2020, Intel Corp.
7  *
8  *****************************************************************************/
9 
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 
13 #define _COMPONENT          ACPI_COMPILER
14 ACPI_MODULE_NAME("utuuid")
15 
16 #if (defined ACPI_ASL_COMPILER || defined ACPI_EXEC_APP || defined ACPI_HELP_APP)
17 /*
18  * UUID support functions.
19  *
20  * This table is used to convert an input UUID ascii string to a 16 byte
21  * buffer and the reverse. The table maps a UUID buffer index 0-15 to
22  * the index within the 36-byte UUID string where the associated 2-byte
23  * hex value can be found.
24  *
25  * 36-byte UUID strings are of the form:
26  *     aabbccdd-eeff-gghh-iijj-kkllmmnnoopp
27  * Where aa-pp are one byte hex numbers, made up of two hex digits
28  *
29  * Note: This table is basically the inverse of the string-to-offset table
30  * found in the ACPI spec in the description of the to_UUID macro.
31  */
32 const u8 acpi_gbl_map_to_uuid_offset[UUID_BUFFER_LENGTH] = {
33 	6, 4, 2, 0, 11, 9, 16, 14, 19, 21, 24, 26, 28, 30, 32, 34
34 };
35 
36 /*******************************************************************************
37  *
38  * FUNCTION:    acpi_ut_convert_string_to_uuid
39  *
40  * PARAMETERS:  in_string           - 36-byte formatted UUID string
41  *              uuid_buffer         - Where the 16-byte UUID buffer is returned
42  *
43  * RETURN:      None. Output data is returned in the uuid_buffer
44  *
45  * DESCRIPTION: Convert a 36-byte formatted UUID string to 16-byte UUID buffer
46  *
47  ******************************************************************************/
48 
49 void acpi_ut_convert_string_to_uuid(char *in_string, u8 *uuid_buffer)
50 {
51 	u32 i;
52 
53 	for (i = 0; i < UUID_BUFFER_LENGTH; i++) {
54 		uuid_buffer[i] =
55 		    (acpi_ut_ascii_char_to_hex
56 		     (in_string[acpi_gbl_map_to_uuid_offset[i]]) << 4);
57 
58 		uuid_buffer[i] |=
59 		    acpi_ut_ascii_char_to_hex(in_string
60 					      [acpi_gbl_map_to_uuid_offset[i] +
61 					       1]);
62 	}
63 }
64 #endif
65