Merge branch 'for-jeff' of git://electric-eye.fr.zoreil.com/home/romieu/linux-2.6
[linux-2.6] / drivers / acpi / executer / exconvrt.c
1 /******************************************************************************
2  *
3  * Module Name: exconvrt - Object conversion routines
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2006, R. Byron Moore
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 <acpi/acinterp.h>
46 #include <acpi/amlcode.h>
47
48 #define _COMPONENT          ACPI_EXECUTER
49 ACPI_MODULE_NAME("exconvrt")
50
51 /* Local prototypes */
52 static u32
53 acpi_ex_convert_to_ascii(acpi_integer integer,
54                          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         acpi_integer 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 (ACPI_GET_OBJECT_TYPE(obj_desc)) {
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                 return_ACPI_STATUS(AE_TYPE);
103         }
104
105         /*
106          * Convert the buffer/string to an integer.  Note that both buffers and
107          * strings are treated as raw data - we don't convert ascii to hex for
108          * strings.
109          *
110          * There are two terminating conditions for the loop:
111          * 1) The size of an integer has been reached, or
112          * 2) The end of the buffer or string has been reached
113          */
114         result = 0;
115
116         /* String conversion is different than Buffer conversion */
117
118         switch (ACPI_GET_OBJECT_TYPE(obj_desc)) {
119         case ACPI_TYPE_STRING:
120
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 |= (((acpi_integer) pointer[i]) << (i * 8));
158                 }
159                 break;
160
161         default:
162                 /* No other types can get here */
163                 break;
164         }
165
166         /* Create a new integer */
167
168         return_desc = acpi_ut_create_internal_object(ACPI_TYPE_INTEGER);
169         if (!return_desc) {
170                 return_ACPI_STATUS(AE_NO_MEMORY);
171         }
172
173         /* Save the Result */
174
175         return_desc->integer.value = result;
176         acpi_ex_truncate_for32bit_table(return_desc);
177         *result_desc = return_desc;
178         return_ACPI_STATUS(AE_OK);
179 }
180
181 /*******************************************************************************
182  *
183  * FUNCTION:    acpi_ex_convert_to_buffer
184  *
185  * PARAMETERS:  obj_desc        - Object to be converted.  Must be an
186  *                                Integer, Buffer, or String
187  *              result_desc     - Where the new buffer object is returned
188  *
189  * RETURN:      Status
190  *
191  * DESCRIPTION: Convert an ACPI Object to a Buffer
192  *
193  ******************************************************************************/
194
195 acpi_status
196 acpi_ex_convert_to_buffer(union acpi_operand_object *obj_desc,
197                           union acpi_operand_object **result_desc)
198 {
199         union acpi_operand_object *return_desc;
200         u8 *new_buf;
201
202         ACPI_FUNCTION_TRACE_PTR("ex_convert_to_buffer", obj_desc);
203
204         switch (ACPI_GET_OBJECT_TYPE(obj_desc)) {
205         case ACPI_TYPE_BUFFER:
206
207                 /* No conversion necessary */
208
209                 *result_desc = obj_desc;
210                 return_ACPI_STATUS(AE_OK);
211
212         case ACPI_TYPE_INTEGER:
213
214                 /*
215                  * Create a new Buffer object.
216                  * Need enough space for one integer
217                  */
218                 return_desc =
219                     acpi_ut_create_buffer_object(acpi_gbl_integer_byte_width);
220                 if (!return_desc) {
221                         return_ACPI_STATUS(AE_NO_MEMORY);
222                 }
223
224                 /* Copy the integer to the buffer, LSB first */
225
226                 new_buf = return_desc->buffer.pointer;
227                 ACPI_MEMCPY(new_buf,
228                             &obj_desc->integer.value,
229                             acpi_gbl_integer_byte_width);
230                 break;
231
232         case ACPI_TYPE_STRING:
233
234                 /*
235                  * Create a new Buffer object
236                  * Size will be the string length
237                  *
238                  * NOTE: Add one to the string length to include the null terminator.
239                  * The ACPI spec is unclear on this subject, but there is existing
240                  * ASL/AML code that depends on the null being transferred to the new
241                  * buffer.
242                  */
243                 return_desc = acpi_ut_create_buffer_object((acpi_size)
244                                                            obj_desc->string.
245                                                            length + 1);
246                 if (!return_desc) {
247                         return_ACPI_STATUS(AE_NO_MEMORY);
248                 }
249
250                 /* Copy the string to the buffer */
251
252                 new_buf = return_desc->buffer.pointer;
253                 ACPI_STRNCPY((char *)new_buf, (char *)obj_desc->string.pointer,
254                              obj_desc->string.length);
255                 break;
256
257         default:
258                 return_ACPI_STATUS(AE_TYPE);
259         }
260
261         /* Mark buffer initialized */
262
263         return_desc->common.flags |= AOPOBJ_DATA_VALID;
264         *result_desc = return_desc;
265         return_ACPI_STATUS(AE_OK);
266 }
267
268 /*******************************************************************************
269  *
270  * FUNCTION:    acpi_ex_convert_to_ascii
271  *
272  * PARAMETERS:  Integer         - Value to be converted
273  *              Base            - ACPI_STRING_DECIMAL or ACPI_STRING_HEX
274  *              String          - Where the string is returned
275  *              data_width      - Size of data item to be converted, in bytes
276  *
277  * RETURN:      Actual string length
278  *
279  * DESCRIPTION: Convert an ACPI Integer to a hex or decimal string
280  *
281  ******************************************************************************/
282
283 static u32
284 acpi_ex_convert_to_ascii(acpi_integer integer,
285                          u16 base, u8 * string, u8 data_width)
286 {
287         acpi_integer digit;
288         acpi_native_uint i;
289         acpi_native_uint j;
290         acpi_native_uint k = 0;
291         acpi_native_uint hex_length;
292         acpi_native_uint decimal_length;
293         u32 remainder;
294         u8 supress_zeros;
295
296         ACPI_FUNCTION_ENTRY();
297
298         switch (base) {
299         case 10:
300
301                 /* Setup max length for the decimal number */
302
303                 switch (data_width) {
304                 case 1:
305                         decimal_length = ACPI_MAX8_DECIMAL_DIGITS;
306                         break;
307
308                 case 4:
309                         decimal_length = ACPI_MAX32_DECIMAL_DIGITS;
310                         break;
311
312                 case 8:
313                 default:
314                         decimal_length = ACPI_MAX64_DECIMAL_DIGITS;
315                         break;
316                 }
317
318                 supress_zeros = TRUE;   /* No leading zeros */
319                 remainder = 0;
320
321                 for (i = decimal_length; i > 0; i--) {
322                         /* Divide by nth factor of 10 */
323
324                         digit = integer;
325                         for (j = 0; j < i; j++) {
326                                 (void)acpi_ut_short_divide(digit, 10, &digit,
327                                                            &remainder);
328                         }
329
330                         /* Handle leading zeros */
331
332                         if (remainder != 0) {
333                                 supress_zeros = FALSE;
334                         }
335
336                         if (!supress_zeros) {
337                                 string[k] = (u8) (ACPI_ASCII_ZERO + remainder);
338                                 k++;
339                         }
340                 }
341                 break;
342
343         case 16:
344
345                 /* hex_length: 2 ascii hex chars per data byte */
346
347                 hex_length = (acpi_native_uint) ACPI_MUL_2(data_width);
348                 for (i = 0, j = (hex_length - 1); i < hex_length; i++, j--) {
349                         /* Get one hex digit, most significant digits first */
350
351                         string[k] =
352                             (u8) acpi_ut_hex_to_ascii_char(integer,
353                                                            ACPI_MUL_4(j));
354                         k++;
355                 }
356                 break;
357
358         default:
359                 return (0);
360         }
361
362         /*
363          * Since leading zeros are supressed, we must check for the case where
364          * the integer equals 0
365          *
366          * Finally, null terminate the string and return the length
367          */
368         if (!k) {
369                 string[0] = ACPI_ASCII_ZERO;
370                 k = 1;
371         }
372
373         string[k] = 0;
374         return ((u32) k);
375 }
376
377 /*******************************************************************************
378  *
379  * FUNCTION:    acpi_ex_convert_to_string
380  *
381  * PARAMETERS:  obj_desc        - Object to be converted.  Must be an
382  *                                Integer, Buffer, or String
383  *              result_desc     - Where the string object is returned
384  *              Type            - String flags (base and conversion type)
385  *
386  * RETURN:      Status
387  *
388  * DESCRIPTION: Convert an ACPI Object to a string
389  *
390  ******************************************************************************/
391
392 acpi_status
393 acpi_ex_convert_to_string(union acpi_operand_object * obj_desc,
394                           union acpi_operand_object ** result_desc, u32 type)
395 {
396         union acpi_operand_object *return_desc;
397         u8 *new_buf;
398         u32 i;
399         u32 string_length = 0;
400         u16 base = 16;
401         u8 separator = ',';
402
403         ACPI_FUNCTION_TRACE_PTR("ex_convert_to_string", obj_desc);
404
405         switch (ACPI_GET_OBJECT_TYPE(obj_desc)) {
406         case ACPI_TYPE_STRING:
407
408                 /* No conversion necessary */
409
410                 *result_desc = obj_desc;
411                 return_ACPI_STATUS(AE_OK);
412
413         case ACPI_TYPE_INTEGER:
414
415                 switch (type) {
416                 case ACPI_EXPLICIT_CONVERT_DECIMAL:
417
418                         /* Make room for maximum decimal number */
419
420                         string_length = ACPI_MAX_DECIMAL_DIGITS;
421                         base = 10;
422                         break;
423
424                 default:
425
426                         /* Two hex string characters for each integer byte */
427
428                         string_length = ACPI_MUL_2(acpi_gbl_integer_byte_width);
429                         break;
430                 }
431
432                 /*
433                  * Create a new String
434                  * Need enough space for one ASCII integer (plus null terminator)
435                  */
436                 return_desc =
437                     acpi_ut_create_string_object((acpi_size) string_length);
438                 if (!return_desc) {
439                         return_ACPI_STATUS(AE_NO_MEMORY);
440                 }
441
442                 new_buf = return_desc->buffer.pointer;
443
444                 /* Convert integer to string */
445
446                 string_length =
447                     acpi_ex_convert_to_ascii(obj_desc->integer.value, base,
448                                              new_buf,
449                                              acpi_gbl_integer_byte_width);
450
451                 /* Null terminate at the correct place */
452
453                 return_desc->string.length = string_length;
454                 new_buf[string_length] = 0;
455                 break;
456
457         case ACPI_TYPE_BUFFER:
458
459                 /* Setup string length, base, and separator */
460
461                 switch (type) {
462                 case ACPI_EXPLICIT_CONVERT_DECIMAL:     /* Used by to_decimal_string */
463                         /*
464                          * From ACPI: "If Data is a buffer, it is converted to a string of
465                          * decimal values separated by commas."
466                          */
467                         base = 10;
468
469                         /*
470                          * Calculate the final string length.  Individual string values
471                          * are variable length (include separator for each)
472                          */
473                         for (i = 0; i < obj_desc->buffer.length; i++) {
474                                 if (obj_desc->buffer.pointer[i] >= 100) {
475                                         string_length += 4;
476                                 } else if (obj_desc->buffer.pointer[i] >= 10) {
477                                         string_length += 3;
478                                 } else {
479                                         string_length += 2;
480                                 }
481                         }
482                         break;
483
484                 case ACPI_IMPLICIT_CONVERT_HEX:
485                         /*
486                          * From the ACPI spec:
487                          *"The entire contents of the buffer are converted to a string of
488                          * two-character hexadecimal numbers, each separated by a space."
489                          */
490                         separator = ' ';
491                         string_length = (obj_desc->buffer.length * 3);
492                         break;
493
494                 case ACPI_EXPLICIT_CONVERT_HEX: /* Used by to_hex_string */
495                         /*
496                          * From ACPI: "If Data is a buffer, it is converted to a string of
497                          * hexadecimal values separated by commas."
498                          */
499                         string_length = (obj_desc->buffer.length * 3);
500                         break;
501
502                 default:
503                         return_ACPI_STATUS(AE_BAD_PARAMETER);
504                 }
505
506                 /*
507                  * Create a new string object and string buffer
508                  * (-1 because of extra separator included in string_length from above)
509                  */
510                 return_desc =
511                     acpi_ut_create_string_object((acpi_size)
512                                                  (string_length - 1));
513                 if (!return_desc) {
514                         return_ACPI_STATUS(AE_NO_MEMORY);
515                 }
516
517                 new_buf = return_desc->buffer.pointer;
518
519                 /*
520                  * Convert buffer bytes to hex or decimal values
521                  * (separated by commas or spaces)
522                  */
523                 for (i = 0; i < obj_desc->buffer.length; i++) {
524                         new_buf += acpi_ex_convert_to_ascii((acpi_integer)
525                                                             obj_desc->buffer.
526                                                             pointer[i], base,
527                                                             new_buf, 1);
528                         *new_buf++ = separator; /* each separated by a comma or space */
529                 }
530
531                 /*
532                  * Null terminate the string
533                  * (overwrites final comma/space from above)
534                  */
535                 new_buf--;
536                 *new_buf = 0;
537                 break;
538
539         default:
540                 return_ACPI_STATUS(AE_TYPE);
541         }
542
543         *result_desc = return_desc;
544         return_ACPI_STATUS(AE_OK);
545 }
546
547 /*******************************************************************************
548  *
549  * FUNCTION:    acpi_ex_convert_to_target_type
550  *
551  * PARAMETERS:  destination_type    - Current type of the destination
552  *              source_desc         - Source object to be converted.
553  *              result_desc         - Where the converted object is returned
554  *              walk_state          - Current method state
555  *
556  * RETURN:      Status
557  *
558  * DESCRIPTION: Implements "implicit conversion" rules for storing an object.
559  *
560  ******************************************************************************/
561
562 acpi_status
563 acpi_ex_convert_to_target_type(acpi_object_type destination_type,
564                                union acpi_operand_object *source_desc,
565                                union acpi_operand_object **result_desc,
566                                struct acpi_walk_state *walk_state)
567 {
568         acpi_status status = AE_OK;
569
570         ACPI_FUNCTION_TRACE("ex_convert_to_target_type");
571
572         /* Default behavior */
573
574         *result_desc = source_desc;
575
576         /*
577          * If required by the target,
578          * perform implicit conversion on the source before we store it.
579          */
580         switch (GET_CURRENT_ARG_TYPE(walk_state->op_info->runtime_args)) {
581         case ARGI_SIMPLE_TARGET:
582         case ARGI_FIXED_TARGET:
583         case ARGI_INTEGER_REF:  /* Handles Increment, Decrement cases */
584
585                 switch (destination_type) {
586                 case ACPI_TYPE_LOCAL_REGION_FIELD:
587                         /*
588                          * Named field can always handle conversions
589                          */
590                         break;
591
592                 default:
593                         /* No conversion allowed for these types */
594
595                         if (destination_type !=
596                             ACPI_GET_OBJECT_TYPE(source_desc)) {
597                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
598                                                   "Explicit operator, will store (%s) over existing type (%s)\n",
599                                                   acpi_ut_get_object_type_name
600                                                   (source_desc),
601                                                   acpi_ut_get_type_name
602                                                   (destination_type)));
603                                 status = AE_TYPE;
604                         }
605                 }
606                 break;
607
608         case ARGI_TARGETREF:
609
610                 switch (destination_type) {
611                 case ACPI_TYPE_INTEGER:
612                 case ACPI_TYPE_BUFFER_FIELD:
613                 case ACPI_TYPE_LOCAL_BANK_FIELD:
614                 case ACPI_TYPE_LOCAL_INDEX_FIELD:
615                         /*
616                          * These types require an Integer operand.  We can convert
617                          * a Buffer or a String to an Integer if necessary.
618                          */
619                         status =
620                             acpi_ex_convert_to_integer(source_desc, result_desc,
621                                                        16);
622                         break;
623
624                 case ACPI_TYPE_STRING:
625                         /*
626                          * The operand must be a String.  We can convert an
627                          * Integer or Buffer if necessary
628                          */
629                         status =
630                             acpi_ex_convert_to_string(source_desc, result_desc,
631                                                       ACPI_IMPLICIT_CONVERT_HEX);
632                         break;
633
634                 case ACPI_TYPE_BUFFER:
635                         /*
636                          * The operand must be a Buffer.  We can convert an
637                          * Integer or String if necessary
638                          */
639                         status =
640                             acpi_ex_convert_to_buffer(source_desc, result_desc);
641                         break;
642
643                 default:
644                         ACPI_ERROR((AE_INFO,
645                                     "Bad destination type during conversion: %X",
646                                     destination_type));
647                         status = AE_AML_INTERNAL;
648                         break;
649                 }
650                 break;
651
652         case ARGI_REFERENCE:
653                 /*
654                  * create_xxxx_field cases - we are storing the field object into the name
655                  */
656                 break;
657
658         default:
659                 ACPI_ERROR((AE_INFO,
660                             "Unknown Target type ID 0x%X aml_opcode %X dest_type %s",
661                             GET_CURRENT_ARG_TYPE(walk_state->op_info->
662                                                  runtime_args),
663                             walk_state->opcode,
664                             acpi_ut_get_type_name(destination_type)));
665                 status = AE_AML_INTERNAL;
666         }
667
668         /*
669          * Source-to-Target conversion semantics:
670          *
671          * If conversion to the target type cannot be performed, then simply
672          * overwrite the target with the new object and type.
673          */
674         if (status == AE_TYPE) {
675                 status = AE_OK;
676         }
677
678         return_ACPI_STATUS(status);
679 }