Merge tag 'char-misc-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregk...
[sfrench/cifs-2.6.git] / drivers / acpi / acpica / evhandler.c
1 /******************************************************************************
2  *
3  * Module Name: evhandler - Support for Address Space handlers
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2014, 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 #include "acinterp.h"
49
50 #define _COMPONENT          ACPI_EVENTS
51 ACPI_MODULE_NAME("evhandler")
52
53 /* Local prototypes */
54 static acpi_status
55 acpi_ev_install_handler(acpi_handle obj_handle,
56                         u32 level, void *context, void **return_value);
57
58 /* These are the address spaces that will get default handlers */
59
60 u8 acpi_gbl_default_address_spaces[ACPI_NUM_DEFAULT_SPACES] = {
61         ACPI_ADR_SPACE_SYSTEM_MEMORY,
62         ACPI_ADR_SPACE_SYSTEM_IO,
63         ACPI_ADR_SPACE_PCI_CONFIG,
64         ACPI_ADR_SPACE_DATA_TABLE
65 };
66
67 /*******************************************************************************
68  *
69  * FUNCTION:    acpi_ev_install_region_handlers
70  *
71  * PARAMETERS:  None
72  *
73  * RETURN:      Status
74  *
75  * DESCRIPTION: Installs the core subsystem default address space handlers.
76  *
77  ******************************************************************************/
78
79 acpi_status acpi_ev_install_region_handlers(void)
80 {
81         acpi_status status;
82         u32 i;
83
84         ACPI_FUNCTION_TRACE(ev_install_region_handlers);
85
86         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
87         if (ACPI_FAILURE(status)) {
88                 return_ACPI_STATUS(status);
89         }
90
91         /*
92          * All address spaces (PCI Config, EC, SMBus) are scope dependent and
93          * registration must occur for a specific device.
94          *
95          * In the case of the system memory and IO address spaces there is
96          * currently no device associated with the address space. For these we
97          * use the root.
98          *
99          * We install the default PCI config space handler at the root so that
100          * this space is immediately available even though the we have not
101          * enumerated all the PCI Root Buses yet. This is to conform to the ACPI
102          * specification which states that the PCI config space must be always
103          * available -- even though we are nowhere near ready to find the PCI root
104          * buses at this point.
105          *
106          * NOTE: We ignore AE_ALREADY_EXISTS because this means that a handler
107          * has already been installed (via acpi_install_address_space_handler).
108          * Similar for AE_SAME_HANDLER.
109          */
110         for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++) {
111                 status = acpi_ev_install_space_handler(acpi_gbl_root_node,
112                                                        acpi_gbl_default_address_spaces
113                                                        [i],
114                                                        ACPI_DEFAULT_HANDLER,
115                                                        NULL, NULL);
116                 switch (status) {
117                 case AE_OK:
118                 case AE_SAME_HANDLER:
119                 case AE_ALREADY_EXISTS:
120
121                         /* These exceptions are all OK */
122
123                         status = AE_OK;
124                         break;
125
126                 default:
127
128                         goto unlock_and_exit;
129                 }
130         }
131
132 unlock_and_exit:
133         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
134         return_ACPI_STATUS(status);
135 }
136
137 /*******************************************************************************
138  *
139  * FUNCTION:    acpi_ev_has_default_handler
140  *
141  * PARAMETERS:  node                - Namespace node for the device
142  *              space_id            - The address space ID
143  *
144  * RETURN:      TRUE if default handler is installed, FALSE otherwise
145  *
146  * DESCRIPTION: Check if the default handler is installed for the requested
147  *              space ID.
148  *
149  ******************************************************************************/
150
151 u8
152 acpi_ev_has_default_handler(struct acpi_namespace_node *node,
153                             acpi_adr_space_type space_id)
154 {
155         union acpi_operand_object *obj_desc;
156         union acpi_operand_object *handler_obj;
157
158         /* Must have an existing internal object */
159
160         obj_desc = acpi_ns_get_attached_object(node);
161         if (obj_desc) {
162                 handler_obj = obj_desc->device.handler;
163
164                 /* Walk the linked list of handlers for this object */
165
166                 while (handler_obj) {
167                         if (handler_obj->address_space.space_id == space_id) {
168                                 if (handler_obj->address_space.handler_flags &
169                                     ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
170                                         return (TRUE);
171                                 }
172                         }
173
174                         handler_obj = handler_obj->address_space.next;
175                 }
176         }
177
178         return (FALSE);
179 }
180
181 /*******************************************************************************
182  *
183  * FUNCTION:    acpi_ev_install_handler
184  *
185  * PARAMETERS:  walk_namespace callback
186  *
187  * DESCRIPTION: This routine installs an address handler into objects that are
188  *              of type Region or Device.
189  *
190  *              If the Object is a Device, and the device has a handler of
191  *              the same type then the search is terminated in that branch.
192  *
193  *              This is because the existing handler is closer in proximity
194  *              to any more regions than the one we are trying to install.
195  *
196  ******************************************************************************/
197
198 static acpi_status
199 acpi_ev_install_handler(acpi_handle obj_handle,
200                         u32 level, void *context, void **return_value)
201 {
202         union acpi_operand_object *handler_obj;
203         union acpi_operand_object *next_handler_obj;
204         union acpi_operand_object *obj_desc;
205         struct acpi_namespace_node *node;
206         acpi_status status;
207
208         ACPI_FUNCTION_NAME(ev_install_handler);
209
210         handler_obj = (union acpi_operand_object *)context;
211
212         /* Parameter validation */
213
214         if (!handler_obj) {
215                 return (AE_OK);
216         }
217
218         /* Convert and validate the device handle */
219
220         node = acpi_ns_validate_handle(obj_handle);
221         if (!node) {
222                 return (AE_BAD_PARAMETER);
223         }
224
225         /*
226          * We only care about regions and objects that are allowed to have
227          * address space handlers
228          */
229         if ((node->type != ACPI_TYPE_DEVICE) &&
230             (node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
231                 return (AE_OK);
232         }
233
234         /* Check for an existing internal object */
235
236         obj_desc = acpi_ns_get_attached_object(node);
237         if (!obj_desc) {
238
239                 /* No object, just exit */
240
241                 return (AE_OK);
242         }
243
244         /* Devices are handled different than regions */
245
246         if (obj_desc->common.type == ACPI_TYPE_DEVICE) {
247
248                 /* Check if this Device already has a handler for this address space */
249
250                 next_handler_obj = obj_desc->device.handler;
251                 while (next_handler_obj) {
252
253                         /* Found a handler, is it for the same address space? */
254
255                         if (next_handler_obj->address_space.space_id ==
256                             handler_obj->address_space.space_id) {
257                                 ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
258                                                   "Found handler for region [%s] in device %p(%p) "
259                                                   "handler %p\n",
260                                                   acpi_ut_get_region_name
261                                                   (handler_obj->address_space.
262                                                    space_id), obj_desc,
263                                                   next_handler_obj,
264                                                   handler_obj));
265
266                                 /*
267                                  * Since the object we found it on was a device, then it
268                                  * means that someone has already installed a handler for
269                                  * the branch of the namespace from this device on. Just
270                                  * bail out telling the walk routine to not traverse this
271                                  * branch. This preserves the scoping rule for handlers.
272                                  */
273                                 return (AE_CTRL_DEPTH);
274                         }
275
276                         /* Walk the linked list of handlers attached to this device */
277
278                         next_handler_obj = next_handler_obj->address_space.next;
279                 }
280
281                 /*
282                  * As long as the device didn't have a handler for this space we
283                  * don't care about it. We just ignore it and proceed.
284                  */
285                 return (AE_OK);
286         }
287
288         /* Object is a Region */
289
290         if (obj_desc->region.space_id != handler_obj->address_space.space_id) {
291
292                 /* This region is for a different address space, just ignore it */
293
294                 return (AE_OK);
295         }
296
297         /*
298          * Now we have a region and it is for the handler's address space type.
299          *
300          * First disconnect region for any previous handler (if any)
301          */
302         acpi_ev_detach_region(obj_desc, FALSE);
303
304         /* Connect the region to the new handler */
305
306         status = acpi_ev_attach_region(handler_obj, obj_desc, FALSE);
307         return (status);
308 }
309
310 /*******************************************************************************
311  *
312  * FUNCTION:    acpi_ev_install_space_handler
313  *
314  * PARAMETERS:  node            - Namespace node for the device
315  *              space_id        - The address space ID
316  *              handler         - Address of the handler
317  *              setup           - Address of the setup function
318  *              context         - Value passed to the handler on each access
319  *
320  * RETURN:      Status
321  *
322  * DESCRIPTION: Install a handler for all op_regions of a given space_id.
323  *              Assumes namespace is locked
324  *
325  ******************************************************************************/
326
327 acpi_status
328 acpi_ev_install_space_handler(struct acpi_namespace_node * node,
329                               acpi_adr_space_type space_id,
330                               acpi_adr_space_handler handler,
331                               acpi_adr_space_setup setup, void *context)
332 {
333         union acpi_operand_object *obj_desc;
334         union acpi_operand_object *handler_obj;
335         acpi_status status;
336         acpi_object_type type;
337         u8 flags = 0;
338
339         ACPI_FUNCTION_TRACE(ev_install_space_handler);
340
341         /*
342          * This registration is valid for only the types below and the root. This
343          * is where the default handlers get placed.
344          */
345         if ((node->type != ACPI_TYPE_DEVICE) &&
346             (node->type != ACPI_TYPE_PROCESSOR) &&
347             (node->type != ACPI_TYPE_THERMAL) && (node != acpi_gbl_root_node)) {
348                 status = AE_BAD_PARAMETER;
349                 goto unlock_and_exit;
350         }
351
352         if (handler == ACPI_DEFAULT_HANDLER) {
353                 flags = ACPI_ADDR_HANDLER_DEFAULT_INSTALLED;
354
355                 switch (space_id) {
356                 case ACPI_ADR_SPACE_SYSTEM_MEMORY:
357
358                         handler = acpi_ex_system_memory_space_handler;
359                         setup = acpi_ev_system_memory_region_setup;
360                         break;
361
362                 case ACPI_ADR_SPACE_SYSTEM_IO:
363
364                         handler = acpi_ex_system_io_space_handler;
365                         setup = acpi_ev_io_space_region_setup;
366                         break;
367
368                 case ACPI_ADR_SPACE_PCI_CONFIG:
369
370                         handler = acpi_ex_pci_config_space_handler;
371                         setup = acpi_ev_pci_config_region_setup;
372                         break;
373
374                 case ACPI_ADR_SPACE_CMOS:
375
376                         handler = acpi_ex_cmos_space_handler;
377                         setup = acpi_ev_cmos_region_setup;
378                         break;
379
380                 case ACPI_ADR_SPACE_PCI_BAR_TARGET:
381
382                         handler = acpi_ex_pci_bar_space_handler;
383                         setup = acpi_ev_pci_bar_region_setup;
384                         break;
385
386                 case ACPI_ADR_SPACE_DATA_TABLE:
387
388                         handler = acpi_ex_data_table_space_handler;
389                         setup = NULL;
390                         break;
391
392                 default:
393
394                         status = AE_BAD_PARAMETER;
395                         goto unlock_and_exit;
396                 }
397         }
398
399         /* If the caller hasn't specified a setup routine, use the default */
400
401         if (!setup) {
402                 setup = acpi_ev_default_region_setup;
403         }
404
405         /* Check for an existing internal object */
406
407         obj_desc = acpi_ns_get_attached_object(node);
408         if (obj_desc) {
409                 /*
410                  * The attached device object already exists. Make sure the handler
411                  * is not already installed.
412                  */
413                 handler_obj = obj_desc->device.handler;
414
415                 /* Walk the handler list for this device */
416
417                 while (handler_obj) {
418
419                         /* Same space_id indicates a handler already installed */
420
421                         if (handler_obj->address_space.space_id == space_id) {
422                                 if (handler_obj->address_space.handler ==
423                                     handler) {
424                                         /*
425                                          * It is (relatively) OK to attempt to install the SAME
426                                          * handler twice. This can easily happen with the
427                                          * PCI_Config space.
428                                          */
429                                         status = AE_SAME_HANDLER;
430                                         goto unlock_and_exit;
431                                 } else {
432                                         /* A handler is already installed */
433
434                                         status = AE_ALREADY_EXISTS;
435                                 }
436                                 goto unlock_and_exit;
437                         }
438
439                         /* Walk the linked list of handlers */
440
441                         handler_obj = handler_obj->address_space.next;
442                 }
443         } else {
444                 ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
445                                   "Creating object on Device %p while installing handler\n",
446                                   node));
447
448                 /* obj_desc does not exist, create one */
449
450                 if (node->type == ACPI_TYPE_ANY) {
451                         type = ACPI_TYPE_DEVICE;
452                 } else {
453                         type = node->type;
454                 }
455
456                 obj_desc = acpi_ut_create_internal_object(type);
457                 if (!obj_desc) {
458                         status = AE_NO_MEMORY;
459                         goto unlock_and_exit;
460                 }
461
462                 /* Init new descriptor */
463
464                 obj_desc->common.type = (u8)type;
465
466                 /* Attach the new object to the Node */
467
468                 status = acpi_ns_attach_object(node, obj_desc, type);
469
470                 /* Remove local reference to the object */
471
472                 acpi_ut_remove_reference(obj_desc);
473
474                 if (ACPI_FAILURE(status)) {
475                         goto unlock_and_exit;
476                 }
477         }
478
479         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
480                           "Installing address handler for region %s(%X) on Device %4.4s %p(%p)\n",
481                           acpi_ut_get_region_name(space_id), space_id,
482                           acpi_ut_get_node_name(node), node, obj_desc));
483
484         /*
485          * Install the handler
486          *
487          * At this point there is no existing handler. Just allocate the object
488          * for the handler and link it into the list.
489          */
490         handler_obj =
491             acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_ADDRESS_HANDLER);
492         if (!handler_obj) {
493                 status = AE_NO_MEMORY;
494                 goto unlock_and_exit;
495         }
496
497         /* Init handler obj */
498
499         handler_obj->address_space.space_id = (u8)space_id;
500         handler_obj->address_space.handler_flags = flags;
501         handler_obj->address_space.region_list = NULL;
502         handler_obj->address_space.node = node;
503         handler_obj->address_space.handler = handler;
504         handler_obj->address_space.context = context;
505         handler_obj->address_space.setup = setup;
506
507         /* Install at head of Device.address_space list */
508
509         handler_obj->address_space.next = obj_desc->device.handler;
510
511         /*
512          * The Device object is the first reference on the handler_obj.
513          * Each region that uses the handler adds a reference.
514          */
515         obj_desc->device.handler = handler_obj;
516
517         /*
518          * Walk the namespace finding all of the regions this
519          * handler will manage.
520          *
521          * Start at the device and search the branch toward
522          * the leaf nodes until either the leaf is encountered or
523          * a device is detected that has an address handler of the
524          * same type.
525          *
526          * In either case, back up and search down the remainder
527          * of the branch
528          */
529         status = acpi_ns_walk_namespace(ACPI_TYPE_ANY, node, ACPI_UINT32_MAX,
530                                         ACPI_NS_WALK_UNLOCK,
531                                         acpi_ev_install_handler, NULL,
532                                         handler_obj, NULL);
533
534 unlock_and_exit:
535         return_ACPI_STATUS(status);
536 }