Merge branch 'stable/bug-fixes-rc1' of git://git.kernel.org/pub/scm/linux/kernel...
[pandora-kernel.git] / drivers / acpi / acpica / evgpeinit.c
1 /******************************************************************************
2  *
3  * Module Name: evgpeinit - System GPE initialization and update
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2011, 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 "acevents.h"
47 #include "acnamesp.h"
48
49 #define _COMPONENT          ACPI_EVENTS
50 ACPI_MODULE_NAME("evgpeinit")
51
52 /*
53  * Note: History of _PRW support in ACPICA
54  *
55  * Originally (2000 - 2010), the GPE initialization code performed a walk of
56  * the entire namespace to execute the _PRW methods and detect all GPEs
57  * capable of waking the system.
58  *
59  * As of 10/2010, the _PRW method execution has been removed since it is
60  * actually unnecessary. The host OS must in fact execute all _PRW methods
61  * in order to identify the device/power-resource dependencies. We now put
62  * the onus on the host OS to identify the wake GPEs as part of this process
63  * and to inform ACPICA of these GPEs via the acpi_setup_gpe_for_wake interface. This
64  * not only reduces the complexity of the ACPICA initialization code, but in
65  * some cases (on systems with very large namespaces) it should reduce the
66  * kernel boot time as well.
67  */
68
69 /*******************************************************************************
70  *
71  * FUNCTION:    acpi_ev_gpe_initialize
72  *
73  * PARAMETERS:  None
74  *
75  * RETURN:      Status
76  *
77  * DESCRIPTION: Initialize the GPE data structures and the FADT GPE 0/1 blocks
78  *
79  ******************************************************************************/
80 acpi_status acpi_ev_gpe_initialize(void)
81 {
82         u32 register_count0 = 0;
83         u32 register_count1 = 0;
84         u32 gpe_number_max = 0;
85         acpi_status status;
86
87         ACPI_FUNCTION_TRACE(ev_gpe_initialize);
88
89         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
90         if (ACPI_FAILURE(status)) {
91                 return_ACPI_STATUS(status);
92         }
93
94         /*
95          * Initialize the GPE Block(s) defined in the FADT
96          *
97          * Why the GPE register block lengths are divided by 2:  From the ACPI
98          * Spec, section "General-Purpose Event Registers", we have:
99          *
100          * "Each register block contains two registers of equal length
101          *  GPEx_STS and GPEx_EN (where x is 0 or 1). The length of the
102          *  GPE0_STS and GPE0_EN registers is equal to half the GPE0_LEN
103          *  The length of the GPE1_STS and GPE1_EN registers is equal to
104          *  half the GPE1_LEN. If a generic register block is not supported
105          *  then its respective block pointer and block length values in the
106          *  FADT table contain zeros. The GPE0_LEN and GPE1_LEN do not need
107          *  to be the same size."
108          */
109
110         /*
111          * Determine the maximum GPE number for this machine.
112          *
113          * Note: both GPE0 and GPE1 are optional, and either can exist without
114          * the other.
115          *
116          * If EITHER the register length OR the block address are zero, then that
117          * particular block is not supported.
118          */
119         if (acpi_gbl_FADT.gpe0_block_length &&
120             acpi_gbl_FADT.xgpe0_block.address) {
121
122                 /* GPE block 0 exists (has both length and address > 0) */
123
124                 register_count0 = (u16)(acpi_gbl_FADT.gpe0_block_length / 2);
125
126                 gpe_number_max =
127                     (register_count0 * ACPI_GPE_REGISTER_WIDTH) - 1;
128
129                 /* Install GPE Block 0 */
130
131                 status = acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
132                                                   &acpi_gbl_FADT.xgpe0_block,
133                                                   register_count0, 0,
134                                                   acpi_gbl_FADT.sci_interrupt,
135                                                   &acpi_gbl_gpe_fadt_blocks[0]);
136
137                 if (ACPI_FAILURE(status)) {
138                         ACPI_EXCEPTION((AE_INFO, status,
139                                         "Could not create GPE Block 0"));
140                 }
141         }
142
143         if (acpi_gbl_FADT.gpe1_block_length &&
144             acpi_gbl_FADT.xgpe1_block.address) {
145
146                 /* GPE block 1 exists (has both length and address > 0) */
147
148                 register_count1 = (u16)(acpi_gbl_FADT.gpe1_block_length / 2);
149
150                 /* Check for GPE0/GPE1 overlap (if both banks exist) */
151
152                 if ((register_count0) &&
153                     (gpe_number_max >= acpi_gbl_FADT.gpe1_base)) {
154                         ACPI_ERROR((AE_INFO,
155                                     "GPE0 block (GPE 0 to %u) overlaps the GPE1 block "
156                                     "(GPE %u to %u) - Ignoring GPE1",
157                                     gpe_number_max, acpi_gbl_FADT.gpe1_base,
158                                     acpi_gbl_FADT.gpe1_base +
159                                     ((register_count1 *
160                                       ACPI_GPE_REGISTER_WIDTH) - 1)));
161
162                         /* Ignore GPE1 block by setting the register count to zero */
163
164                         register_count1 = 0;
165                 } else {
166                         /* Install GPE Block 1 */
167
168                         status =
169                             acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
170                                                      &acpi_gbl_FADT.xgpe1_block,
171                                                      register_count1,
172                                                      acpi_gbl_FADT.gpe1_base,
173                                                      acpi_gbl_FADT.
174                                                      sci_interrupt,
175                                                      &acpi_gbl_gpe_fadt_blocks
176                                                      [1]);
177
178                         if (ACPI_FAILURE(status)) {
179                                 ACPI_EXCEPTION((AE_INFO, status,
180                                                 "Could not create GPE Block 1"));
181                         }
182
183                         /*
184                          * GPE0 and GPE1 do not have to be contiguous in the GPE number
185                          * space. However, GPE0 always starts at GPE number zero.
186                          */
187                         gpe_number_max = acpi_gbl_FADT.gpe1_base +
188                             ((register_count1 * ACPI_GPE_REGISTER_WIDTH) - 1);
189                 }
190         }
191
192         /* Exit if there are no GPE registers */
193
194         if ((register_count0 + register_count1) == 0) {
195
196                 /* GPEs are not required by ACPI, this is OK */
197
198                 ACPI_DEBUG_PRINT((ACPI_DB_INIT,
199                                   "There are no GPE blocks defined in the FADT\n"));
200                 status = AE_OK;
201                 goto cleanup;
202         }
203
204         /* Check for Max GPE number out-of-range */
205
206         if (gpe_number_max > ACPI_GPE_MAX) {
207                 ACPI_ERROR((AE_INFO,
208                             "Maximum GPE number from FADT is too large: 0x%X",
209                             gpe_number_max));
210                 status = AE_BAD_VALUE;
211                 goto cleanup;
212         }
213
214       cleanup:
215         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
216         return_ACPI_STATUS(AE_OK);
217 }
218
219 /*******************************************************************************
220  *
221  * FUNCTION:    acpi_ev_update_gpes
222  *
223  * PARAMETERS:  table_owner_id      - ID of the newly-loaded ACPI table
224  *
225  * RETURN:      None
226  *
227  * DESCRIPTION: Check for new GPE methods (_Lxx/_Exx) made available as a
228  *              result of a Load() or load_table() operation. If new GPE
229  *              methods have been installed, register the new methods.
230  *
231  ******************************************************************************/
232
233 void acpi_ev_update_gpes(acpi_owner_id table_owner_id)
234 {
235         struct acpi_gpe_xrupt_info *gpe_xrupt_info;
236         struct acpi_gpe_block_info *gpe_block;
237         struct acpi_gpe_walk_info walk_info;
238         acpi_status status = AE_OK;
239
240         /*
241          * Find any _Lxx/_Exx GPE methods that have just been loaded.
242          *
243          * Any GPEs that correspond to new _Lxx/_Exx methods are immediately
244          * enabled.
245          *
246          * Examine the namespace underneath each gpe_device within the
247          * gpe_block lists.
248          */
249         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
250         if (ACPI_FAILURE(status)) {
251                 return;
252         }
253
254         walk_info.count = 0;
255         walk_info.owner_id = table_owner_id;
256         walk_info.execute_by_owner_id = TRUE;
257
258         /* Walk the interrupt level descriptor list */
259
260         gpe_xrupt_info = acpi_gbl_gpe_xrupt_list_head;
261         while (gpe_xrupt_info) {
262
263                 /* Walk all Gpe Blocks attached to this interrupt level */
264
265                 gpe_block = gpe_xrupt_info->gpe_block_list_head;
266                 while (gpe_block) {
267                         walk_info.gpe_block = gpe_block;
268                         walk_info.gpe_device = gpe_block->node;
269
270                         status = acpi_ns_walk_namespace(ACPI_TYPE_METHOD,
271                                                         walk_info.gpe_device,
272                                                         ACPI_UINT32_MAX,
273                                                         ACPI_NS_WALK_NO_UNLOCK,
274                                                         acpi_ev_match_gpe_method,
275                                                         NULL, &walk_info, NULL);
276                         if (ACPI_FAILURE(status)) {
277                                 ACPI_EXCEPTION((AE_INFO, status,
278                                                 "While decoding _Lxx/_Exx methods"));
279                         }
280
281                         gpe_block = gpe_block->next;
282                 }
283
284                 gpe_xrupt_info = gpe_xrupt_info->next;
285         }
286
287         if (walk_info.count) {
288                 ACPI_INFO((AE_INFO, "Enabled %u new GPEs", walk_info.count));
289         }
290
291         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
292         return;
293 }
294
295 /*******************************************************************************
296  *
297  * FUNCTION:    acpi_ev_match_gpe_method
298  *
299  * PARAMETERS:  Callback from walk_namespace
300  *
301  * RETURN:      Status
302  *
303  * DESCRIPTION: Called from acpi_walk_namespace. Expects each object to be a
304  *              control method under the _GPE portion of the namespace.
305  *              Extract the name and GPE type from the object, saving this
306  *              information for quick lookup during GPE dispatch. Allows a
307  *              per-owner_id evaluation if execute_by_owner_id is TRUE in the
308  *              walk_info parameter block.
309  *
310  *              The name of each GPE control method is of the form:
311  *              "_Lxx" or "_Exx", where:
312  *                  L      - means that the GPE is level triggered
313  *                  E      - means that the GPE is edge triggered
314  *                  xx     - is the GPE number [in HEX]
315  *
316  * If walk_info->execute_by_owner_id is TRUE, we only execute examine GPE methods
317  * with that owner.
318  *
319  ******************************************************************************/
320
321 acpi_status
322 acpi_ev_match_gpe_method(acpi_handle obj_handle,
323                          u32 level, void *context, void **return_value)
324 {
325         struct acpi_namespace_node *method_node =
326             ACPI_CAST_PTR(struct acpi_namespace_node, obj_handle);
327         struct acpi_gpe_walk_info *walk_info =
328             ACPI_CAST_PTR(struct acpi_gpe_walk_info, context);
329         struct acpi_gpe_event_info *gpe_event_info;
330         u32 gpe_number;
331         char name[ACPI_NAME_SIZE + 1];
332         u8 type;
333
334         ACPI_FUNCTION_TRACE(ev_match_gpe_method);
335
336         /* Check if requested owner_id matches this owner_id */
337
338         if ((walk_info->execute_by_owner_id) &&
339             (method_node->owner_id != walk_info->owner_id)) {
340                 return_ACPI_STATUS(AE_OK);
341         }
342
343         /*
344          * Match and decode the _Lxx and _Exx GPE method names
345          *
346          * 1) Extract the method name and null terminate it
347          */
348         ACPI_MOVE_32_TO_32(name, &method_node->name.integer);
349         name[ACPI_NAME_SIZE] = 0;
350
351         /* 2) Name must begin with an underscore */
352
353         if (name[0] != '_') {
354                 return_ACPI_STATUS(AE_OK);      /* Ignore this method */
355         }
356
357         /*
358          * 3) Edge/Level determination is based on the 2nd character
359          *    of the method name
360          */
361         switch (name[1]) {
362         case 'L':
363                 type = ACPI_GPE_LEVEL_TRIGGERED;
364                 break;
365
366         case 'E':
367                 type = ACPI_GPE_EDGE_TRIGGERED;
368                 break;
369
370         default:
371                 /* Unknown method type, just ignore it */
372
373                 ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
374                                   "Ignoring unknown GPE method type: %s "
375                                   "(name not of form _Lxx or _Exx)", name));
376                 return_ACPI_STATUS(AE_OK);
377         }
378
379         /* 4) The last two characters of the name are the hex GPE Number */
380
381         gpe_number = ACPI_STRTOUL(&name[2], NULL, 16);
382         if (gpe_number == ACPI_UINT32_MAX) {
383
384                 /* Conversion failed; invalid method, just ignore it */
385
386                 ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
387                                   "Could not extract GPE number from name: %s "
388                                   "(name is not of form _Lxx or _Exx)", name));
389                 return_ACPI_STATUS(AE_OK);
390         }
391
392         /* Ensure that we have a valid GPE number for this GPE block */
393
394         gpe_event_info =
395             acpi_ev_low_get_gpe_info(gpe_number, walk_info->gpe_block);
396         if (!gpe_event_info) {
397                 /*
398                  * This gpe_number is not valid for this GPE block, just ignore it.
399                  * However, it may be valid for a different GPE block, since GPE0
400                  * and GPE1 methods both appear under \_GPE.
401                  */
402                 return_ACPI_STATUS(AE_OK);
403         }
404
405         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
406             ACPI_GPE_DISPATCH_HANDLER) {
407
408                 /* If there is already a handler, ignore this GPE method */
409
410                 return_ACPI_STATUS(AE_OK);
411         }
412
413         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
414             ACPI_GPE_DISPATCH_METHOD) {
415                 /*
416                  * If there is already a method, ignore this method. But check
417                  * for a type mismatch (if both the _Lxx AND _Exx exist)
418                  */
419                 if (type != (gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK)) {
420                         ACPI_ERROR((AE_INFO,
421                                     "For GPE 0x%.2X, found both _L%2.2X and _E%2.2X methods",
422                                     gpe_number, gpe_number, gpe_number));
423                 }
424                 return_ACPI_STATUS(AE_OK);
425         }
426
427         /* Disable the GPE in case it's been enabled already. */
428         (void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
429
430         /*
431          * Add the GPE information from above to the gpe_event_info block for
432          * use during dispatch of this GPE.
433          */
434         gpe_event_info->flags &= ~(ACPI_GPE_DISPATCH_MASK);
435         gpe_event_info->flags |= (u8)(type | ACPI_GPE_DISPATCH_METHOD);
436         gpe_event_info->dispatch.method_node = method_node;
437
438         ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
439                           "Registered GPE method %s as GPE number 0x%.2X\n",
440                           name, gpe_number));
441         return_ACPI_STATUS(AE_OK);
442 }