Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
[sfrench/cifs-2.6.git] / drivers / acpi / acpica / exconvrt.c
1 /******************************************************************************
2  *
3  * Module Name: exconvrt - Object conversion routines
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2015, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acinterp.h"
47 #include "amlcode.h"
48
49 #define _COMPONENT          ACPI_EXECUTER
50 ACPI_MODULE_NAME("exconvrt")
51
52 /* Local prototypes */
53 static u32
54 acpi_ex_convert_to_ascii(u64 integer, u16 base, u8 *string, u8 max_length);
55
56 /*******************************************************************************
57  *
58  * FUNCTION:    acpi_ex_convert_to_integer
59  *
60  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
61  *                                Integer, Buffer, or String
62  *              result_desc     - Where the new Integer object is returned
63  *              flags           - Used for string conversion
64  *
65  * RETURN:      Status
66  *
67  * DESCRIPTION: Convert an ACPI Object to an integer.
68  *
69  ******************************************************************************/
70
71 acpi_status
72 acpi_ex_convert_to_integer(union acpi_operand_object *obj_desc,
73                            union acpi_operand_object **result_desc, u32 flags)
74 {
75         union acpi_operand_object *return_desc;
76         u8 *pointer;
77         u64 result;
78         u32 i;
79         u32 count;
80         acpi_status status;
81
82         ACPI_FUNCTION_TRACE_PTR(ex_convert_to_integer, obj_desc);
83
84         switch (obj_desc->common.type) {
85         case ACPI_TYPE_INTEGER:
86
87                 /* No conversion necessary */
88
89                 *result_desc = obj_desc;
90                 return_ACPI_STATUS(AE_OK);
91
92         case ACPI_TYPE_BUFFER:
93         case ACPI_TYPE_STRING:
94
95                 /* Note: Takes advantage of common buffer/string fields */
96
97                 pointer = obj_desc->buffer.pointer;
98                 count = obj_desc->buffer.length;
99                 break;
100
101         default:
102
103                 return_ACPI_STATUS(AE_TYPE);
104         }
105
106         /*
107          * Convert the buffer/string to an integer. Note that both buffers and
108          * strings are treated as raw data - we don't convert ascii to hex for
109          * strings.
110          *
111          * There are two terminating conditions for the loop:
112          * 1) The size of an integer has been reached, or
113          * 2) The end of the buffer or string has been reached
114          */
115         result = 0;
116
117         /* String conversion is different than Buffer conversion */
118
119         switch (obj_desc->common.type) {
120         case ACPI_TYPE_STRING:
121                 /*
122                  * Convert string to an integer - for most cases, the string must be
123                  * hexadecimal as per the ACPI specification. The only exception (as
124                  * of ACPI 3.0) is that the to_integer() operator allows both decimal
125                  * and hexadecimal strings (hex prefixed with "0x").
126                  */
127                 status = acpi_ut_strtoul64((char *)pointer, flags, &result);
128                 if (ACPI_FAILURE(status)) {
129                         return_ACPI_STATUS(status);
130                 }
131                 break;
132
133         case ACPI_TYPE_BUFFER:
134
135                 /* Check for zero-length buffer */
136
137                 if (!count) {
138                         return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
139                 }
140
141                 /* Transfer no more than an integer's worth of data */
142
143                 if (count > acpi_gbl_integer_byte_width) {
144                         count = acpi_gbl_integer_byte_width;
145                 }
146
147                 /*
148                  * Convert buffer to an integer - we simply grab enough raw data
149                  * from the buffer to fill an integer
150                  */
151                 for (i = 0; i < count; i++) {
152                         /*
153                          * Get next byte and shift it into the Result.
154                          * Little endian is used, meaning that the first byte of the buffer
155                          * is the LSB of the integer
156                          */
157                         result |= (((u64) pointer[i]) << (i * 8));
158                 }
159                 break;
160
161         default:
162
163                 /* No other types can get here */
164
165                 break;
166         }
167
168         /* Create a new integer */
169
170         return_desc = acpi_ut_create_integer_object(result);
171         if (!return_desc) {
172                 return_ACPI_STATUS(AE_NO_MEMORY);
173         }
174
175         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Converted value: %8.8X%8.8X\n",
176                           ACPI_FORMAT_UINT64(result)));
177
178         /* Save the Result */
179
180         (void)acpi_ex_truncate_for32bit_table(return_desc);
181         *result_desc = return_desc;
182         return_ACPI_STATUS(AE_OK);
183 }
184
185 /*******************************************************************************
186  *
187  * FUNCTION:    acpi_ex_convert_to_buffer
188  *
189  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
190  *                                Integer, Buffer, or String
191  *              result_desc     - Where the new buffer object is returned
192  *
193  * RETURN:      Status
194  *
195  * DESCRIPTION: Convert an ACPI Object to a Buffer
196  *
197  ******************************************************************************/
198
199 acpi_status
200 acpi_ex_convert_to_buffer(union acpi_operand_object *obj_desc,
201                           union acpi_operand_object **result_desc)
202 {
203         union acpi_operand_object *return_desc;
204         u8 *new_buf;
205
206         ACPI_FUNCTION_TRACE_PTR(ex_convert_to_buffer, obj_desc);
207
208         switch (obj_desc->common.type) {
209         case ACPI_TYPE_BUFFER:
210
211                 /* No conversion necessary */
212
213                 *result_desc = obj_desc;
214                 return_ACPI_STATUS(AE_OK);
215
216         case ACPI_TYPE_INTEGER:
217                 /*
218                  * Create a new Buffer object.
219                  * Need enough space for one integer
220                  */
221                 return_desc =
222                     acpi_ut_create_buffer_object(acpi_gbl_integer_byte_width);
223                 if (!return_desc) {
224                         return_ACPI_STATUS(AE_NO_MEMORY);
225                 }
226
227                 /* Copy the integer to the buffer, LSB first */
228
229                 new_buf = return_desc->buffer.pointer;
230                 memcpy(new_buf,
231                        &obj_desc->integer.value, acpi_gbl_integer_byte_width);
232                 break;
233
234         case ACPI_TYPE_STRING:
235                 /*
236                  * Create a new Buffer object
237                  * Size will be the string length
238                  *
239                  * NOTE: Add one to the string length to include the null terminator.
240                  * The ACPI spec is unclear on this subject, but there is existing
241                  * ASL/AML code that depends on the null being transferred to the new
242                  * buffer.
243                  */
244                 return_desc = acpi_ut_create_buffer_object((acpi_size)
245                                                            obj_desc->string.
246                                                            length + 1);
247                 if (!return_desc) {
248                         return_ACPI_STATUS(AE_NO_MEMORY);
249                 }
250
251                 /* Copy the string to the buffer */
252
253                 new_buf = return_desc->buffer.pointer;
254                 strncpy((char *)new_buf, (char *)obj_desc->string.pointer,
255                         obj_desc->string.length);
256                 break;
257
258         default:
259
260                 return_ACPI_STATUS(AE_TYPE);
261         }
262
263         /* Mark buffer initialized */
264
265         return_desc->common.flags |= AOPOBJ_DATA_VALID;
266         *result_desc = return_desc;
267         return_ACPI_STATUS(AE_OK);
268 }
269
270 /*******************************************************************************
271  *
272  * FUNCTION:    acpi_ex_convert_to_ascii
273  *
274  * PARAMETERS:  integer         - Value to be converted
275  *              base            - ACPI_STRING_DECIMAL or ACPI_STRING_HEX
276  *              string          - Where the string is returned
277  *              data_width      - Size of data item to be converted, in bytes
278  *
279  * RETURN:      Actual string length
280  *
281  * DESCRIPTION: Convert an ACPI Integer to a hex or decimal string
282  *
283  ******************************************************************************/
284
285 static u32
286 acpi_ex_convert_to_ascii(u64 integer, u16 base, u8 *string, u8 data_width)
287 {
288         u64 digit;
289         u32 i;
290         u32 j;
291         u32 k = 0;
292         u32 hex_length;
293         u32 decimal_length;
294         u32 remainder;
295         u8 supress_zeros;
296
297         ACPI_FUNCTION_ENTRY();
298
299         switch (base) {
300         case 10:
301
302                 /* Setup max length for the decimal number */
303
304                 switch (data_width) {
305                 case 1:
306
307                         decimal_length = ACPI_MAX8_DECIMAL_DIGITS;
308                         break;
309
310                 case 4:
311
312                         decimal_length = ACPI_MAX32_DECIMAL_DIGITS;
313                         break;
314
315                 case 8:
316                 default:
317
318                         decimal_length = ACPI_MAX64_DECIMAL_DIGITS;
319                         break;
320                 }
321
322                 supress_zeros = TRUE;   /* No leading zeros */
323                 remainder = 0;
324
325                 for (i = decimal_length; i > 0; i--) {
326
327                         /* Divide by nth factor of 10 */
328
329                         digit = integer;
330                         for (j = 0; j < i; j++) {
331                                 (void)acpi_ut_short_divide(digit, 10, &digit,
332                                                            &remainder);
333                         }
334
335                         /* Handle leading zeros */
336
337                         if (remainder != 0) {
338                                 supress_zeros = FALSE;
339                         }
340
341                         if (!supress_zeros) {
342                                 string[k] = (u8) (ACPI_ASCII_ZERO + remainder);
343                                 k++;
344                         }
345                 }
346                 break;
347
348         case 16:
349
350                 /* hex_length: 2 ascii hex chars per data byte */
351
352                 hex_length = ACPI_MUL_2(data_width);
353                 for (i = 0, j = (hex_length - 1); i < hex_length; i++, j--) {
354
355                         /* Get one hex digit, most significant digits first */
356
357                         string[k] =
358                             (u8) acpi_ut_hex_to_ascii_char(integer,
359                                                            ACPI_MUL_4(j));
360                         k++;
361                 }
362                 break;
363
364         default:
365                 return (0);
366         }
367
368         /*
369          * Since leading zeros are suppressed, we must check for the case where
370          * the integer equals 0
371          *
372          * Finally, null terminate the string and return the length
373          */
374         if (!k) {
375                 string[0] = ACPI_ASCII_ZERO;
376                 k = 1;
377         }
378
379         string[k] = 0;
380         return ((u32) k);
381 }
382
383 /*******************************************************************************
384  *
385  * FUNCTION:    acpi_ex_convert_to_string
386  *
387  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
388  *                                Integer, Buffer, or String
389  *              result_desc     - Where the string object is returned
390  *              type            - String flags (base and conversion type)
391  *
392  * RETURN:      Status
393  *
394  * DESCRIPTION: Convert an ACPI Object to a string
395  *
396  ******************************************************************************/
397
398 acpi_status
399 acpi_ex_convert_to_string(union acpi_operand_object * obj_desc,
400                           union acpi_operand_object ** result_desc, u32 type)
401 {
402         union acpi_operand_object *return_desc;
403         u8 *new_buf;
404         u32 i;
405         u32 string_length = 0;
406         u16 base = 16;
407         u8 separator = ',';
408
409         ACPI_FUNCTION_TRACE_PTR(ex_convert_to_string, obj_desc);
410
411         switch (obj_desc->common.type) {
412         case ACPI_TYPE_STRING:
413
414                 /* No conversion necessary */
415
416                 *result_desc = obj_desc;
417                 return_ACPI_STATUS(AE_OK);
418
419         case ACPI_TYPE_INTEGER:
420
421                 switch (type) {
422                 case ACPI_EXPLICIT_CONVERT_DECIMAL:
423
424                         /* Make room for maximum decimal number */
425
426                         string_length = ACPI_MAX_DECIMAL_DIGITS;
427                         base = 10;
428                         break;
429
430                 default:
431
432                         /* Two hex string characters for each integer byte */
433
434                         string_length = ACPI_MUL_2(acpi_gbl_integer_byte_width);
435                         break;
436                 }
437
438                 /*
439                  * Create a new String
440                  * Need enough space for one ASCII integer (plus null terminator)
441                  */
442                 return_desc =
443                     acpi_ut_create_string_object((acpi_size) string_length);
444                 if (!return_desc) {
445                         return_ACPI_STATUS(AE_NO_MEMORY);
446                 }
447
448                 new_buf = return_desc->buffer.pointer;
449
450                 /* Convert integer to string */
451
452                 string_length =
453                     acpi_ex_convert_to_ascii(obj_desc->integer.value, base,
454                                              new_buf,
455                                              acpi_gbl_integer_byte_width);
456
457                 /* Null terminate at the correct place */
458
459                 return_desc->string.length = string_length;
460                 new_buf[string_length] = 0;
461                 break;
462
463         case ACPI_TYPE_BUFFER:
464
465                 /* Setup string length, base, and separator */
466
467                 switch (type) {
468                 case ACPI_EXPLICIT_CONVERT_DECIMAL:     /* Used by to_decimal_string */
469                         /*
470                          * From ACPI: "If Data is a buffer, it is converted to a string of
471                          * decimal values separated by commas."
472                          */
473                         base = 10;
474
475                         /*
476                          * Calculate the final string length. Individual string values
477                          * are variable length (include separator for each)
478                          */
479                         for (i = 0; i < obj_desc->buffer.length; i++) {
480                                 if (obj_desc->buffer.pointer[i] >= 100) {
481                                         string_length += 4;
482                                 } else if (obj_desc->buffer.pointer[i] >= 10) {
483                                         string_length += 3;
484                                 } else {
485                                         string_length += 2;
486                                 }
487                         }
488                         break;
489
490                 case ACPI_IMPLICIT_CONVERT_HEX:
491                         /*
492                          * From the ACPI spec:
493                          *"The entire contents of the buffer are converted to a string of
494                          * two-character hexadecimal numbers, each separated by a space."
495                          */
496                         separator = ' ';
497                         string_length = (obj_desc->buffer.length * 3);
498                         break;
499
500                 case ACPI_EXPLICIT_CONVERT_HEX: /* Used by to_hex_string */
501                         /*
502                          * From ACPI: "If Data is a buffer, it is converted to a string of
503                          * hexadecimal values separated by commas."
504                          */
505                         string_length = (obj_desc->buffer.length * 3);
506                         break;
507
508                 default:
509                         return_ACPI_STATUS(AE_BAD_PARAMETER);
510                 }
511
512                 /*
513                  * Create a new string object and string buffer
514                  * (-1 because of extra separator included in string_length from above)
515                  * Allow creation of zero-length strings from zero-length buffers.
516                  */
517                 if (string_length) {
518                         string_length--;
519                 }
520
521                 return_desc =
522                     acpi_ut_create_string_object((acpi_size) string_length);
523                 if (!return_desc) {
524                         return_ACPI_STATUS(AE_NO_MEMORY);
525                 }
526
527                 new_buf = return_desc->buffer.pointer;
528
529                 /*
530                  * Convert buffer bytes to hex or decimal values
531                  * (separated by commas or spaces)
532                  */
533                 for (i = 0; i < obj_desc->buffer.length; i++) {
534                         new_buf += acpi_ex_convert_to_ascii((u64) obj_desc->
535                                                             buffer.pointer[i],
536                                                             base, new_buf, 1);
537                         *new_buf++ = separator; /* each separated by a comma or space */
538                 }
539
540                 /*
541                  * Null terminate the string
542                  * (overwrites final comma/space from above)
543                  */
544                 if (obj_desc->buffer.length) {
545                         new_buf--;
546                 }
547                 *new_buf = 0;
548                 break;
549
550         default:
551
552                 return_ACPI_STATUS(AE_TYPE);
553         }
554
555         *result_desc = return_desc;
556         return_ACPI_STATUS(AE_OK);
557 }
558
559 /*******************************************************************************
560  *
561  * FUNCTION:    acpi_ex_convert_to_target_type
562  *
563  * PARAMETERS:  destination_type    - Current type of the destination
564  *              source_desc         - Source object to be converted.
565  *              result_desc         - Where the converted object is returned
566  *              walk_state          - Current method state
567  *
568  * RETURN:      Status
569  *
570  * DESCRIPTION: Implements "implicit conversion" rules for storing an object.
571  *
572  ******************************************************************************/
573
574 acpi_status
575 acpi_ex_convert_to_target_type(acpi_object_type destination_type,
576                                union acpi_operand_object *source_desc,
577                                union acpi_operand_object **result_desc,
578                                struct acpi_walk_state *walk_state)
579 {
580         acpi_status status = AE_OK;
581
582         ACPI_FUNCTION_TRACE(ex_convert_to_target_type);
583
584         /* Default behavior */
585
586         *result_desc = source_desc;
587
588         /*
589          * If required by the target,
590          * perform implicit conversion on the source before we store it.
591          */
592         switch (GET_CURRENT_ARG_TYPE(walk_state->op_info->runtime_args)) {
593         case ARGI_SIMPLE_TARGET:
594         case ARGI_FIXED_TARGET:
595         case ARGI_INTEGER_REF:  /* Handles Increment, Decrement cases */
596
597                 switch (destination_type) {
598                 case ACPI_TYPE_LOCAL_REGION_FIELD:
599                         /*
600                          * Named field can always handle conversions
601                          */
602                         break;
603
604                 default:
605
606                         /* No conversion allowed for these types */
607
608                         if (destination_type != source_desc->common.type) {
609                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
610                                                   "Explicit operator, will store (%s) over existing type (%s)\n",
611                                                   acpi_ut_get_object_type_name
612                                                   (source_desc),
613                                                   acpi_ut_get_type_name
614                                                   (destination_type)));
615                                 status = AE_TYPE;
616                         }
617                 }
618                 break;
619
620         case ARGI_TARGETREF:
621
622                 switch (destination_type) {
623                 case ACPI_TYPE_INTEGER:
624                 case ACPI_TYPE_BUFFER_FIELD:
625                 case ACPI_TYPE_LOCAL_BANK_FIELD:
626                 case ACPI_TYPE_LOCAL_INDEX_FIELD:
627                         /*
628                          * These types require an Integer operand. We can convert
629                          * a Buffer or a String to an Integer if necessary.
630                          */
631                         status =
632                             acpi_ex_convert_to_integer(source_desc, result_desc,
633                                                        16);
634                         break;
635
636                 case ACPI_TYPE_STRING:
637                         /*
638                          * The operand must be a String. We can convert an
639                          * Integer or Buffer if necessary
640                          */
641                         status =
642                             acpi_ex_convert_to_string(source_desc, result_desc,
643                                                       ACPI_IMPLICIT_CONVERT_HEX);
644                         break;
645
646                 case ACPI_TYPE_BUFFER:
647                         /*
648                          * The operand must be a Buffer. We can convert an
649                          * Integer or String if necessary
650                          */
651                         status =
652                             acpi_ex_convert_to_buffer(source_desc, result_desc);
653                         break;
654
655                 default:
656
657                         ACPI_ERROR((AE_INFO,
658                                     "Bad destination type during conversion: 0x%X",
659                                     destination_type));
660                         status = AE_AML_INTERNAL;
661                         break;
662                 }
663                 break;
664
665         case ARGI_REFERENCE:
666                 /*
667                  * create_xxxx_field cases - we are storing the field object into the name
668                  */
669                 break;
670
671         default:
672
673                 ACPI_ERROR((AE_INFO,
674                             "Unknown Target type ID 0x%X AmlOpcode 0x%X DestType %s",
675                             GET_CURRENT_ARG_TYPE(walk_state->op_info->
676                                                  runtime_args),
677                             walk_state->opcode,
678                             acpi_ut_get_type_name(destination_type)));
679                 status = AE_AML_INTERNAL;
680         }
681
682         /*
683          * Source-to-Target conversion semantics:
684          *
685          * If conversion to the target type cannot be performed, then simply
686          * overwrite the target with the new object and type.
687          */
688         if (status == AE_TYPE) {
689                 status = AE_OK;
690         }
691
692         return_ACPI_STATUS(status);
693 }