Merge branch 'writeback' of git://git.kernel.dk/linux-2.6-block
[linux-block.git] / drivers / acpi / acpica / exfield.c
CommitLineData
1da177e4
LT
1/******************************************************************************
2 *
3 * Module Name: exfield - ACPI AML (p-code) execution - field manipulation
4 *
5 *****************************************************************************/
6
7/*
75a44ce0 8 * Copyright (C) 2000 - 2008, Intel Corp.
1da177e4
LT
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
1da177e4 44#include <acpi/acpi.h>
e2f7a777
LB
45#include "accommon.h"
46#include "acdispat.h"
47#include "acinterp.h"
1da177e4 48
1da177e4 49#define _COMPONENT ACPI_EXECUTER
4be44fcd 50ACPI_MODULE_NAME("exfield")
1da177e4
LT
51
52/*******************************************************************************
53 *
54 * FUNCTION: acpi_ex_read_data_from_field
55 *
56 * PARAMETERS: walk_state - Current execution state
57 * obj_desc - The named field
58 * ret_buffer_desc - Where the return data object is stored
59 *
60 * RETURN: Status
61 *
62 * DESCRIPTION: Read from a named field. Returns either an Integer or a
63 * Buffer, depending on the size of the field.
64 *
65 ******************************************************************************/
1da177e4 66acpi_status
4be44fcd
LB
67acpi_ex_read_data_from_field(struct acpi_walk_state *walk_state,
68 union acpi_operand_object *obj_desc,
69 union acpi_operand_object **ret_buffer_desc)
1da177e4 70{
4be44fcd
LB
71 acpi_status status;
72 union acpi_operand_object *buffer_desc;
73 acpi_size length;
74 void *buffer;
6557a49a 75 u32 function;
1da177e4 76
b229cf92 77 ACPI_FUNCTION_TRACE_PTR(ex_read_data_from_field, obj_desc);
1da177e4
LT
78
79 /* Parameter validation */
80
81 if (!obj_desc) {
4be44fcd 82 return_ACPI_STATUS(AE_AML_NO_OPERAND);
1da177e4 83 }
88ac00f5 84 if (!ret_buffer_desc) {
4be44fcd 85 return_ACPI_STATUS(AE_BAD_PARAMETER);
88ac00f5 86 }
1da177e4 87
3371c19c 88 if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
1da177e4
LT
89 /*
90 * If the buffer_field arguments have not been previously evaluated,
91 * evaluate them now and save the results.
92 */
93 if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
4be44fcd
LB
94 status = acpi_ds_get_buffer_field_arguments(obj_desc);
95 if (ACPI_FAILURE(status)) {
96 return_ACPI_STATUS(status);
1da177e4
LT
97 }
98 }
3371c19c
BM
99 } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
100 (obj_desc->field.region_obj->region.space_id ==
6557a49a
LM
101 ACPI_ADR_SPACE_SMBUS
102 || obj_desc->field.region_obj->region.space_id ==
103 ACPI_ADR_SPACE_IPMI)) {
1da177e4 104 /*
6557a49a
LM
105 * This is an SMBus or IPMI read. We must create a buffer to hold
106 * the data and then directly access the region handler.
107 *
108 * Note: Smbus protocol value is passed in upper 16-bits of Function
1da177e4 109 */
6557a49a
LM
110 if (obj_desc->field.region_obj->region.space_id ==
111 ACPI_ADR_SPACE_SMBUS) {
112 length = ACPI_SMBUS_BUFFER_SIZE;
113 function =
114 ACPI_READ | (obj_desc->field.attribute << 16);
115 } else { /* IPMI */
116
117 length = ACPI_IPMI_BUFFER_SIZE;
118 function = ACPI_READ;
119 }
120
121 buffer_desc = acpi_ut_create_buffer_object(length);
1da177e4 122 if (!buffer_desc) {
4be44fcd 123 return_ACPI_STATUS(AE_NO_MEMORY);
1da177e4
LT
124 }
125
126 /* Lock entire transaction if requested */
127
ba886cd4 128 acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
1da177e4 129
6557a49a
LM
130 /* Call the region handler for the read */
131
4be44fcd
LB
132 status = acpi_ex_access_region(obj_desc, 0,
133 ACPI_CAST_PTR(acpi_integer,
134 buffer_desc->
135 buffer.pointer),
6557a49a 136 function);
f02e9fa1 137 acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
1da177e4
LT
138 goto exit;
139 }
140
141 /*
142 * Allocate a buffer for the contents of the field.
143 *
144 * If the field is larger than the size of an acpi_integer, create
145 * a BUFFER to hold it. Otherwise, use an INTEGER. This allows
146 * the use of arithmetic operators on the returned value if the
147 * field size is equal or smaller than an Integer.
148 *
149 * Note: Field.length is in bits.
150 */
4be44fcd
LB
151 length =
152 (acpi_size) ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.bit_length);
1da177e4 153 if (length > acpi_gbl_integer_byte_width) {
52fc0b02 154
1da177e4
LT
155 /* Field is too large for an Integer, create a Buffer instead */
156
4be44fcd 157 buffer_desc = acpi_ut_create_buffer_object(length);
1da177e4 158 if (!buffer_desc) {
4be44fcd 159 return_ACPI_STATUS(AE_NO_MEMORY);
1da177e4
LT
160 }
161 buffer = buffer_desc->buffer.pointer;
4be44fcd 162 } else {
1da177e4
LT
163 /* Field will fit within an Integer (normal case) */
164
4be44fcd 165 buffer_desc = acpi_ut_create_internal_object(ACPI_TYPE_INTEGER);
1da177e4 166 if (!buffer_desc) {
4be44fcd 167 return_ACPI_STATUS(AE_NO_MEMORY);
1da177e4
LT
168 }
169
170 length = acpi_gbl_integer_byte_width;
171 buffer_desc->integer.value = 0;
172 buffer = &buffer_desc->integer.value;
173 }
174
4be44fcd 175 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
b229cf92 176 "FieldRead [TO]: Obj %p, Type %X, Buf %p, ByteLen %X\n",
3371c19c 177 obj_desc, obj_desc->common.type, buffer,
4be44fcd
LB
178 (u32) length));
179 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
b229cf92 180 "FieldRead [FROM]: BitLen %X, BitOff %X, ByteOff %X\n",
4be44fcd
LB
181 obj_desc->common_field.bit_length,
182 obj_desc->common_field.start_field_bit_offset,
183 obj_desc->common_field.base_byte_offset));
1da177e4
LT
184
185 /* Lock entire transaction if requested */
186
ba886cd4 187 acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
1da177e4
LT
188
189 /* Read from the field */
190
4be44fcd 191 status = acpi_ex_extract_from_field(obj_desc, buffer, (u32) length);
f02e9fa1 192 acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
1da177e4 193
4be44fcd
LB
194 exit:
195 if (ACPI_FAILURE(status)) {
196 acpi_ut_remove_reference(buffer_desc);
197 } else {
1da177e4
LT
198 *ret_buffer_desc = buffer_desc;
199 }
200
4be44fcd 201 return_ACPI_STATUS(status);
1da177e4
LT
202}
203
1da177e4
LT
204/*******************************************************************************
205 *
206 * FUNCTION: acpi_ex_write_data_to_field
207 *
208 * PARAMETERS: source_desc - Contains data to write
209 * obj_desc - The named field
44f6c012 210 * result_desc - Where the return value is returned, if any
1da177e4
LT
211 *
212 * RETURN: Status
213 *
214 * DESCRIPTION: Write to a named field
215 *
216 ******************************************************************************/
217
218acpi_status
4be44fcd
LB
219acpi_ex_write_data_to_field(union acpi_operand_object *source_desc,
220 union acpi_operand_object *obj_desc,
221 union acpi_operand_object **result_desc)
1da177e4 222{
4be44fcd
LB
223 acpi_status status;
224 u32 length;
4be44fcd 225 void *buffer;
4be44fcd 226 union acpi_operand_object *buffer_desc;
6557a49a 227 u32 function;
1da177e4 228
b229cf92 229 ACPI_FUNCTION_TRACE_PTR(ex_write_data_to_field, obj_desc);
1da177e4
LT
230
231 /* Parameter validation */
232
233 if (!source_desc || !obj_desc) {
4be44fcd 234 return_ACPI_STATUS(AE_AML_NO_OPERAND);
1da177e4
LT
235 }
236
3371c19c 237 if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
1da177e4
LT
238 /*
239 * If the buffer_field arguments have not been previously evaluated,
240 * evaluate them now and save the results.
241 */
242 if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
4be44fcd
LB
243 status = acpi_ds_get_buffer_field_arguments(obj_desc);
244 if (ACPI_FAILURE(status)) {
245 return_ACPI_STATUS(status);
1da177e4
LT
246 }
247 }
3371c19c
BM
248 } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
249 (obj_desc->field.region_obj->region.space_id ==
6557a49a
LM
250 ACPI_ADR_SPACE_SMBUS
251 || obj_desc->field.region_obj->region.space_id ==
252 ACPI_ADR_SPACE_IPMI)) {
1da177e4 253 /*
6557a49a
LM
254 * This is an SMBus or IPMI write. We will bypass the entire field
255 * mechanism and handoff the buffer directly to the handler. For
256 * these address spaces, the buffer is bi-directional; on a write,
257 * return data is returned in the same buffer.
258 *
259 * Source must be a buffer of sufficient size:
260 * ACPI_SMBUS_BUFFER_SIZE or ACPI_IPMI_BUFFER_SIZE.
1da177e4 261 *
6557a49a 262 * Note: SMBus protocol type is passed in upper 16-bits of Function
1da177e4 263 */
3371c19c 264 if (source_desc->common.type != ACPI_TYPE_BUFFER) {
b8e4d893 265 ACPI_ERROR((AE_INFO,
6557a49a 266 "SMBus or IPMI write requires Buffer, found type %s",
b8e4d893 267 acpi_ut_get_object_type_name(source_desc)));
44f6c012 268
4be44fcd 269 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
1da177e4
LT
270 }
271
6557a49a
LM
272 if (obj_desc->field.region_obj->region.space_id ==
273 ACPI_ADR_SPACE_SMBUS) {
274 length = ACPI_SMBUS_BUFFER_SIZE;
275 function =
276 ACPI_WRITE | (obj_desc->field.attribute << 16);
277 } else { /* IPMI */
278
279 length = ACPI_IPMI_BUFFER_SIZE;
280 function = ACPI_WRITE;
281 }
282
283 if (source_desc->buffer.length < length) {
b8e4d893 284 ACPI_ERROR((AE_INFO,
6557a49a
LM
285 "SMBus or IPMI write requires Buffer of length %X, found length %X",
286 length, source_desc->buffer.length));
44f6c012 287
4be44fcd 288 return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
1da177e4
LT
289 }
290
6557a49a
LM
291 /* Create the bi-directional buffer */
292
293 buffer_desc = acpi_ut_create_buffer_object(length);
1da177e4 294 if (!buffer_desc) {
4be44fcd 295 return_ACPI_STATUS(AE_NO_MEMORY);
1da177e4
LT
296 }
297
298 buffer = buffer_desc->buffer.pointer;
6557a49a 299 ACPI_MEMCPY(buffer, source_desc->buffer.pointer, length);
1da177e4
LT
300
301 /* Lock entire transaction if requested */
302
ba886cd4 303 acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
1da177e4
LT
304
305 /*
44f6c012
RM
306 * Perform the write (returns status and perhaps data in the
307 * same buffer)
1da177e4 308 */
4be44fcd
LB
309 status = acpi_ex_access_region(obj_desc, 0,
310 (acpi_integer *) buffer,
6557a49a 311 function);
f02e9fa1 312 acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
1da177e4
LT
313
314 *result_desc = buffer_desc;
4be44fcd 315 return_ACPI_STATUS(status);
1da177e4
LT
316 }
317
44f6c012
RM
318 /* Get a pointer to the data to be written */
319
3371c19c 320 switch (source_desc->common.type) {
1da177e4
LT
321 case ACPI_TYPE_INTEGER:
322 buffer = &source_desc->integer.value;
4be44fcd 323 length = sizeof(source_desc->integer.value);
1da177e4
LT
324 break;
325
326 case ACPI_TYPE_BUFFER:
327 buffer = source_desc->buffer.pointer;
328 length = source_desc->buffer.length;
329 break;
330
331 case ACPI_TYPE_STRING:
332 buffer = source_desc->string.pointer;
333 length = source_desc->string.length;
334 break;
335
336 default:
4be44fcd 337 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
1da177e4
LT
338 }
339
4be44fcd 340 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
b229cf92 341 "FieldWrite [FROM]: Obj %p (%s:%X), Buf %p, ByteLen %X\n",
4be44fcd 342 source_desc,
3371c19c
BM
343 acpi_ut_get_type_name(source_desc->common.type),
344 source_desc->common.type, buffer, length));
4be44fcd
LB
345
346 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
b229cf92 347 "FieldWrite [TO]: Obj %p (%s:%X), BitLen %X, BitOff %X, ByteOff %X\n",
4be44fcd 348 obj_desc,
3371c19c
BM
349 acpi_ut_get_type_name(obj_desc->common.type),
350 obj_desc->common.type,
4be44fcd
LB
351 obj_desc->common_field.bit_length,
352 obj_desc->common_field.start_field_bit_offset,
353 obj_desc->common_field.base_byte_offset));
1da177e4
LT
354
355 /* Lock entire transaction if requested */
356
ba886cd4 357 acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
1da177e4
LT
358
359 /* Write to the field */
360
4be44fcd 361 status = acpi_ex_insert_into_field(obj_desc, buffer, length);
f02e9fa1 362 acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
1da177e4 363
4be44fcd 364 return_ACPI_STATUS(status);
1da177e4 365}