selftests: drivers/dma-buf: Fix implicit declaration warns
[platform/kernel/linux-rpi.git] / drivers / platform / x86 / intel / hid.c
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *  Intel HID event & 5 button array driver
4  *
5  *  Copyright (C) 2015 Alex Hung <alex.hung@canonical.com>
6  *  Copyright (C) 2015 Andrew Lutomirski <luto@kernel.org>
7  */
8
9 #include <linux/acpi.h>
10 #include <linux/dmi.h>
11 #include <linux/input.h>
12 #include <linux/input/sparse-keymap.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/suspend.h>
17 #include "../dual_accel_detect.h"
18
19 /* When NOT in tablet mode, VGBS returns with the flag 0x40 */
20 #define TABLET_MODE_FLAG BIT(6)
21
22 MODULE_LICENSE("GPL");
23 MODULE_AUTHOR("Alex Hung");
24
25 static const struct acpi_device_id intel_hid_ids[] = {
26         {"INT33D5", 0},
27         {"INTC1051", 0},
28         {"INTC1054", 0},
29         {"INTC1070", 0},
30         {"", 0},
31 };
32 MODULE_DEVICE_TABLE(acpi, intel_hid_ids);
33
34 /* In theory, these are HID usages. */
35 static const struct key_entry intel_hid_keymap[] = {
36         /* 1: LSuper (Page 0x07, usage 0xE3) -- unclear what to do */
37         /* 2: Toggle SW_ROTATE_LOCK -- easy to implement if seen in wild */
38         { KE_KEY, 3, { KEY_NUMLOCK } },
39         { KE_KEY, 4, { KEY_HOME } },
40         { KE_KEY, 5, { KEY_END } },
41         { KE_KEY, 6, { KEY_PAGEUP } },
42         { KE_KEY, 7, { KEY_PAGEDOWN } },
43         { KE_KEY, 8, { KEY_RFKILL } },
44         { KE_KEY, 9, { KEY_POWER } },
45         { KE_KEY, 11, { KEY_SLEEP } },
46         /* 13 has two different meanings in the spec -- ignore it. */
47         { KE_KEY, 14, { KEY_STOPCD } },
48         { KE_KEY, 15, { KEY_PLAYPAUSE } },
49         { KE_KEY, 16, { KEY_MUTE } },
50         { KE_KEY, 17, { KEY_VOLUMEUP } },
51         { KE_KEY, 18, { KEY_VOLUMEDOWN } },
52         { KE_KEY, 19, { KEY_BRIGHTNESSUP } },
53         { KE_KEY, 20, { KEY_BRIGHTNESSDOWN } },
54         /* 27: wake -- needs special handling */
55         { KE_END },
56 };
57
58 /* 5 button array notification value. */
59 static const struct key_entry intel_array_keymap[] = {
60         { KE_KEY,    0xC2, { KEY_LEFTMETA } },                /* Press */
61         { KE_IGNORE, 0xC3, { KEY_LEFTMETA } },                /* Release */
62         { KE_KEY,    0xC4, { KEY_VOLUMEUP } },                /* Press */
63         { KE_IGNORE, 0xC5, { KEY_VOLUMEUP } },                /* Release */
64         { KE_KEY,    0xC6, { KEY_VOLUMEDOWN } },              /* Press */
65         { KE_IGNORE, 0xC7, { KEY_VOLUMEDOWN } },              /* Release */
66         { KE_KEY,    0xC8, { KEY_ROTATE_LOCK_TOGGLE } },      /* Press */
67         { KE_IGNORE, 0xC9, { KEY_ROTATE_LOCK_TOGGLE } },      /* Release */
68         { KE_KEY,    0xCE, { KEY_POWER } },                   /* Press */
69         { KE_IGNORE, 0xCF, { KEY_POWER } },                   /* Release */
70         { KE_END },
71 };
72
73 static const struct dmi_system_id button_array_table[] = {
74         {
75                 .ident = "Wacom MobileStudio Pro 13",
76                 .matches = {
77                         DMI_MATCH(DMI_SYS_VENDOR, "Wacom Co.,Ltd"),
78                         DMI_MATCH(DMI_PRODUCT_NAME, "Wacom MobileStudio Pro 13"),
79                 },
80         },
81         {
82                 .ident = "Wacom MobileStudio Pro 16",
83                 .matches = {
84                         DMI_MATCH(DMI_SYS_VENDOR, "Wacom Co.,Ltd"),
85                         DMI_MATCH(DMI_PRODUCT_NAME, "Wacom MobileStudio Pro 16"),
86                 },
87         },
88         {
89                 .ident = "HP Spectre x2 (2015)",
90                 .matches = {
91                         DMI_MATCH(DMI_SYS_VENDOR, "HP"),
92                         DMI_MATCH(DMI_PRODUCT_NAME, "HP Spectre x2 Detachable"),
93                 },
94         },
95         {
96                 .ident = "Lenovo ThinkPad X1 Tablet Gen 2",
97                 .matches = {
98                         DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
99                         DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Tablet Gen 2"),
100                 },
101         },
102         { }
103 };
104
105 /*
106  * Some convertible use the intel-hid ACPI interface to report SW_TABLET_MODE,
107  * these need to be compared via a DMI based authorization list because some
108  * models have unreliable VGBS return which could cause incorrect
109  * SW_TABLET_MODE report.
110  */
111 static const struct dmi_system_id dmi_vgbs_allow_list[] = {
112         {
113                 .matches = {
114                         DMI_MATCH(DMI_SYS_VENDOR, "HP"),
115                         DMI_MATCH(DMI_PRODUCT_NAME, "HP Spectre x360 Convertible 15-df0xxx"),
116                 },
117         },
118         { }
119 };
120
121 struct intel_hid_priv {
122         struct input_dev *input_dev;
123         struct input_dev *array;
124         struct input_dev *switches;
125         bool wakeup_mode;
126         bool dual_accel;
127 };
128
129 #define HID_EVENT_FILTER_UUID   "eeec56b3-4442-408f-a792-4edd4d758054"
130
131 enum intel_hid_dsm_fn_codes {
132         INTEL_HID_DSM_FN_INVALID,
133         INTEL_HID_DSM_BTNL_FN,
134         INTEL_HID_DSM_HDMM_FN,
135         INTEL_HID_DSM_HDSM_FN,
136         INTEL_HID_DSM_HDEM_FN,
137         INTEL_HID_DSM_BTNS_FN,
138         INTEL_HID_DSM_BTNE_FN,
139         INTEL_HID_DSM_HEBC_V1_FN,
140         INTEL_HID_DSM_VGBS_FN,
141         INTEL_HID_DSM_HEBC_V2_FN,
142         INTEL_HID_DSM_FN_MAX
143 };
144
145 static const char *intel_hid_dsm_fn_to_method[INTEL_HID_DSM_FN_MAX] = {
146         NULL,
147         "BTNL",
148         "HDMM",
149         "HDSM",
150         "HDEM",
151         "BTNS",
152         "BTNE",
153         "HEBC",
154         "VGBS",
155         "HEBC"
156 };
157
158 static unsigned long long intel_hid_dsm_fn_mask;
159 static guid_t intel_dsm_guid;
160
161 static bool intel_hid_execute_method(acpi_handle handle,
162                                      enum intel_hid_dsm_fn_codes fn_index,
163                                      unsigned long long arg)
164 {
165         union acpi_object *obj, argv4, req;
166         acpi_status status;
167         char *method_name;
168
169         if (fn_index <= INTEL_HID_DSM_FN_INVALID ||
170             fn_index >= INTEL_HID_DSM_FN_MAX)
171                 return false;
172
173         method_name = (char *)intel_hid_dsm_fn_to_method[fn_index];
174
175         if (!(intel_hid_dsm_fn_mask & BIT(fn_index)))
176                 goto skip_dsm_exec;
177
178         /* All methods expects a package with one integer element */
179         req.type = ACPI_TYPE_INTEGER;
180         req.integer.value = arg;
181
182         argv4.type = ACPI_TYPE_PACKAGE;
183         argv4.package.count = 1;
184         argv4.package.elements = &req;
185
186         obj = acpi_evaluate_dsm(handle, &intel_dsm_guid, 1, fn_index, &argv4);
187         if (obj) {
188                 acpi_handle_debug(handle, "Exec DSM Fn code: %d[%s] success\n",
189                                   fn_index, method_name);
190                 ACPI_FREE(obj);
191                 return true;
192         }
193
194 skip_dsm_exec:
195         status = acpi_execute_simple_method(handle, method_name, arg);
196         if (ACPI_SUCCESS(status))
197                 return true;
198
199         return false;
200 }
201
202 static bool intel_hid_evaluate_method(acpi_handle handle,
203                                       enum intel_hid_dsm_fn_codes fn_index,
204                                       unsigned long long *result)
205 {
206         union acpi_object *obj;
207         acpi_status status;
208         char *method_name;
209
210         if (fn_index <= INTEL_HID_DSM_FN_INVALID ||
211             fn_index >= INTEL_HID_DSM_FN_MAX)
212                 return false;
213
214         method_name = (char *)intel_hid_dsm_fn_to_method[fn_index];
215
216         if (!(intel_hid_dsm_fn_mask & fn_index))
217                 goto skip_dsm_eval;
218
219         obj = acpi_evaluate_dsm_typed(handle, &intel_dsm_guid,
220                                       1, fn_index,
221                                       NULL,  ACPI_TYPE_INTEGER);
222         if (obj) {
223                 *result = obj->integer.value;
224                 acpi_handle_debug(handle,
225                                   "Eval DSM Fn code: %d[%s] results: 0x%llx\n",
226                                   fn_index, method_name, *result);
227                 ACPI_FREE(obj);
228                 return true;
229         }
230
231 skip_dsm_eval:
232         status = acpi_evaluate_integer(handle, method_name, NULL, result);
233         if (ACPI_SUCCESS(status))
234                 return true;
235
236         return false;
237 }
238
239 static void intel_hid_init_dsm(acpi_handle handle)
240 {
241         union acpi_object *obj;
242
243         guid_parse(HID_EVENT_FILTER_UUID, &intel_dsm_guid);
244
245         obj = acpi_evaluate_dsm_typed(handle, &intel_dsm_guid, 1, 0, NULL,
246                                       ACPI_TYPE_BUFFER);
247         if (obj) {
248                 switch (obj->buffer.length) {
249                 default:
250                 case 2:
251                         intel_hid_dsm_fn_mask = *(u16 *)obj->buffer.pointer;
252                         break;
253                 case 1:
254                         intel_hid_dsm_fn_mask = *obj->buffer.pointer;
255                         break;
256                 case 0:
257                         acpi_handle_warn(handle, "intel_hid_dsm_fn_mask length is zero\n");
258                         intel_hid_dsm_fn_mask = 0;
259                         break;
260                 }
261                 ACPI_FREE(obj);
262         }
263
264         acpi_handle_debug(handle, "intel_hid_dsm_fn_mask = %llx\n",
265                           intel_hid_dsm_fn_mask);
266 }
267
268 static int intel_hid_set_enable(struct device *device, bool enable)
269 {
270         acpi_handle handle = ACPI_HANDLE(device);
271
272         /* Enable|disable features - power button is always enabled */
273         if (!intel_hid_execute_method(handle, INTEL_HID_DSM_HDSM_FN,
274                                       enable)) {
275                 dev_warn(device, "failed to %sable hotkeys\n",
276                          enable ? "en" : "dis");
277                 return -EIO;
278         }
279
280         return 0;
281 }
282
283 static void intel_button_array_enable(struct device *device, bool enable)
284 {
285         struct intel_hid_priv *priv = dev_get_drvdata(device);
286         acpi_handle handle = ACPI_HANDLE(device);
287         unsigned long long button_cap;
288         acpi_status status;
289
290         if (!priv->array)
291                 return;
292
293         /* Query supported platform features */
294         status = acpi_evaluate_integer(handle, "BTNC", NULL, &button_cap);
295         if (ACPI_FAILURE(status)) {
296                 dev_warn(device, "failed to get button capability\n");
297                 return;
298         }
299
300         /* Enable|disable features - power button is always enabled */
301         if (!intel_hid_execute_method(handle, INTEL_HID_DSM_BTNE_FN,
302                                       enable ? button_cap : 1))
303                 dev_warn(device, "failed to set button capability\n");
304 }
305
306 static int intel_hid_pm_prepare(struct device *device)
307 {
308         if (device_may_wakeup(device)) {
309                 struct intel_hid_priv *priv = dev_get_drvdata(device);
310
311                 priv->wakeup_mode = true;
312         }
313         return 0;
314 }
315
316 static void intel_hid_pm_complete(struct device *device)
317 {
318         struct intel_hid_priv *priv = dev_get_drvdata(device);
319
320         priv->wakeup_mode = false;
321 }
322
323 static int intel_hid_pl_suspend_handler(struct device *device)
324 {
325         intel_button_array_enable(device, false);
326
327         if (!pm_suspend_no_platform())
328                 intel_hid_set_enable(device, false);
329
330         return 0;
331 }
332
333 static int intel_hid_pl_resume_handler(struct device *device)
334 {
335         intel_hid_pm_complete(device);
336
337         if (!pm_suspend_no_platform())
338                 intel_hid_set_enable(device, true);
339
340         intel_button_array_enable(device, true);
341         return 0;
342 }
343
344 static const struct dev_pm_ops intel_hid_pl_pm_ops = {
345         .prepare = intel_hid_pm_prepare,
346         .complete = intel_hid_pm_complete,
347         .freeze  = intel_hid_pl_suspend_handler,
348         .thaw  = intel_hid_pl_resume_handler,
349         .restore  = intel_hid_pl_resume_handler,
350         .suspend  = intel_hid_pl_suspend_handler,
351         .resume  = intel_hid_pl_resume_handler,
352 };
353
354 static int intel_hid_input_setup(struct platform_device *device)
355 {
356         struct intel_hid_priv *priv = dev_get_drvdata(&device->dev);
357         int ret;
358
359         priv->input_dev = devm_input_allocate_device(&device->dev);
360         if (!priv->input_dev)
361                 return -ENOMEM;
362
363         ret = sparse_keymap_setup(priv->input_dev, intel_hid_keymap, NULL);
364         if (ret)
365                 return ret;
366
367         priv->input_dev->name = "Intel HID events";
368         priv->input_dev->id.bustype = BUS_HOST;
369
370         return input_register_device(priv->input_dev);
371 }
372
373 static int intel_button_array_input_setup(struct platform_device *device)
374 {
375         struct intel_hid_priv *priv = dev_get_drvdata(&device->dev);
376         int ret;
377
378         /* Setup input device for 5 button array */
379         priv->array = devm_input_allocate_device(&device->dev);
380         if (!priv->array)
381                 return -ENOMEM;
382
383         ret = sparse_keymap_setup(priv->array, intel_array_keymap, NULL);
384         if (ret)
385                 return ret;
386
387         priv->array->name = "Intel HID 5 button array";
388         priv->array->id.bustype = BUS_HOST;
389
390         return input_register_device(priv->array);
391 }
392
393 static int intel_hid_switches_setup(struct platform_device *device)
394 {
395         struct intel_hid_priv *priv = dev_get_drvdata(&device->dev);
396
397         /* Setup input device for switches */
398         priv->switches = devm_input_allocate_device(&device->dev);
399         if (!priv->switches)
400                 return -ENOMEM;
401
402         __set_bit(EV_SW, priv->switches->evbit);
403         __set_bit(SW_TABLET_MODE, priv->switches->swbit);
404
405         priv->switches->name = "Intel HID switches";
406         priv->switches->id.bustype = BUS_HOST;
407         return input_register_device(priv->switches);
408 }
409
410 static void report_tablet_mode_state(struct platform_device *device)
411 {
412         struct intel_hid_priv *priv = dev_get_drvdata(&device->dev);
413         acpi_handle handle = ACPI_HANDLE(&device->dev);
414         unsigned long long vgbs;
415         int m;
416
417         if (!intel_hid_evaluate_method(handle, INTEL_HID_DSM_VGBS_FN, &vgbs))
418                 return;
419
420         m = !(vgbs & TABLET_MODE_FLAG);
421         input_report_switch(priv->switches, SW_TABLET_MODE, m);
422         input_sync(priv->switches);
423 }
424
425 static bool report_tablet_mode_event(struct input_dev *input_dev, u32 event)
426 {
427         if (!input_dev)
428                 return false;
429
430         switch (event) {
431         case 0xcc:
432                 input_report_switch(input_dev, SW_TABLET_MODE, 1);
433                 input_sync(input_dev);
434                 return true;
435         case 0xcd:
436                 input_report_switch(input_dev, SW_TABLET_MODE, 0);
437                 input_sync(input_dev);
438                 return true;
439         default:
440                 return false;
441         }
442 }
443
444 static void notify_handler(acpi_handle handle, u32 event, void *context)
445 {
446         struct platform_device *device = context;
447         struct intel_hid_priv *priv = dev_get_drvdata(&device->dev);
448         unsigned long long ev_index;
449         int err;
450
451         /*
452          * Some convertible have unreliable VGBS return which could cause incorrect
453          * SW_TABLET_MODE report, in these cases we enable support when receiving
454          * the first event instead of during driver setup.
455          *
456          * See dual_accel_detect.h for more info on the dual_accel check.
457          */
458         if (!priv->switches && !priv->dual_accel && (event == 0xcc || event == 0xcd)) {
459                 dev_info(&device->dev, "switch event received, enable switches supports\n");
460                 err = intel_hid_switches_setup(device);
461                 if (err)
462                         pr_err("Failed to setup Intel HID switches\n");
463         }
464
465         if (priv->wakeup_mode) {
466                 /*
467                  * Needed for wakeup from suspend-to-idle to work on some
468                  * platforms that don't expose the 5-button array, but still
469                  * send notifies with the power button event code to this
470                  * device object on power button actions while suspended.
471                  */
472                 if (event == 0xce)
473                         goto wakeup;
474
475                 /*
476                  * Some devices send (duplicate) tablet-mode events when moved
477                  * around even though the mode has not changed; and they do this
478                  * even when suspended.
479                  * Update the switch state in case it changed and then return
480                  * without waking up to avoid spurious wakeups.
481                  */
482                 if (event == 0xcc || event == 0xcd) {
483                         report_tablet_mode_event(priv->switches, event);
484                         return;
485                 }
486
487                 /* Wake up on 5-button array events only. */
488                 if (event == 0xc0 || !priv->array)
489                         return;
490
491                 if (!sparse_keymap_entry_from_scancode(priv->array, event)) {
492                         dev_info(&device->dev, "unknown event 0x%x\n", event);
493                         return;
494                 }
495
496 wakeup:
497                 pm_wakeup_hard_event(&device->dev);
498
499                 return;
500         }
501
502         /*
503          * Needed for suspend to work on some platforms that don't expose
504          * the 5-button array, but still send notifies with power button
505          * event code to this device object on power button actions.
506          *
507          * Report the power button press and release.
508          */
509         if (!priv->array) {
510                 if (event == 0xce) {
511                         input_report_key(priv->input_dev, KEY_POWER, 1);
512                         input_sync(priv->input_dev);
513                         return;
514                 }
515
516                 if (event == 0xcf) {
517                         input_report_key(priv->input_dev, KEY_POWER, 0);
518                         input_sync(priv->input_dev);
519                         return;
520                 }
521         }
522
523         if (report_tablet_mode_event(priv->switches, event))
524                 return;
525
526         /* 0xC0 is for HID events, other values are for 5 button array */
527         if (event != 0xc0) {
528                 if (!priv->array ||
529                     !sparse_keymap_report_event(priv->array, event, 1, true))
530                         dev_dbg(&device->dev, "unknown event 0x%x\n", event);
531                 return;
532         }
533
534         if (!intel_hid_evaluate_method(handle, INTEL_HID_DSM_HDEM_FN,
535                                        &ev_index)) {
536                 dev_warn(&device->dev, "failed to get event index\n");
537                 return;
538         }
539
540         if (!sparse_keymap_report_event(priv->input_dev, ev_index, 1, true))
541                 dev_dbg(&device->dev, "unknown event index 0x%llx\n",
542                          ev_index);
543 }
544
545 static bool button_array_present(struct platform_device *device)
546 {
547         acpi_handle handle = ACPI_HANDLE(&device->dev);
548         unsigned long long event_cap;
549
550         if (intel_hid_evaluate_method(handle, INTEL_HID_DSM_HEBC_V2_FN,
551                                       &event_cap)) {
552                 /* Check presence of 5 button array or v2 power button */
553                 if (event_cap & 0x60000)
554                         return true;
555         }
556
557         if (intel_hid_evaluate_method(handle, INTEL_HID_DSM_HEBC_V1_FN,
558                                       &event_cap)) {
559                 if (event_cap & 0x20000)
560                         return true;
561         }
562
563         if (dmi_check_system(button_array_table))
564                 return true;
565
566         return false;
567 }
568
569 static int intel_hid_probe(struct platform_device *device)
570 {
571         acpi_handle handle = ACPI_HANDLE(&device->dev);
572         unsigned long long mode;
573         struct intel_hid_priv *priv;
574         acpi_status status;
575         int err;
576
577         intel_hid_init_dsm(handle);
578
579         if (!intel_hid_evaluate_method(handle, INTEL_HID_DSM_HDMM_FN, &mode)) {
580                 dev_warn(&device->dev, "failed to read mode\n");
581                 return -ENODEV;
582         }
583
584         if (mode != 0) {
585                 /*
586                  * This driver only implements "simple" mode.  There appear
587                  * to be no other modes, but we should be paranoid and check
588                  * for compatibility.
589                  */
590                 dev_info(&device->dev, "platform is not in simple mode\n");
591                 return -ENODEV;
592         }
593
594         priv = devm_kzalloc(&device->dev, sizeof(*priv), GFP_KERNEL);
595         if (!priv)
596                 return -ENOMEM;
597         dev_set_drvdata(&device->dev, priv);
598
599         priv->dual_accel = dual_accel_detect();
600
601         err = intel_hid_input_setup(device);
602         if (err) {
603                 pr_err("Failed to setup Intel HID hotkeys\n");
604                 return err;
605         }
606
607         /* Setup 5 button array */
608         if (button_array_present(device)) {
609                 dev_info(&device->dev, "platform supports 5 button array\n");
610                 err = intel_button_array_input_setup(device);
611                 if (err)
612                         pr_err("Failed to setup Intel 5 button array hotkeys\n");
613         }
614
615         /* Setup switches for devices that we know VGBS return correctly */
616         if (dmi_check_system(dmi_vgbs_allow_list)) {
617                 dev_info(&device->dev, "platform supports switches\n");
618                 err = intel_hid_switches_setup(device);
619                 if (err)
620                         pr_err("Failed to setup Intel HID switches\n");
621                 else
622                         report_tablet_mode_state(device);
623         }
624
625         status = acpi_install_notify_handler(handle,
626                                              ACPI_DEVICE_NOTIFY,
627                                              notify_handler,
628                                              device);
629         if (ACPI_FAILURE(status))
630                 return -EBUSY;
631
632         err = intel_hid_set_enable(&device->dev, true);
633         if (err)
634                 goto err_remove_notify;
635
636         if (priv->array) {
637                 unsigned long long dummy;
638
639                 intel_button_array_enable(&device->dev, true);
640
641                 /* Call button load method to enable HID power button */
642                 if (!intel_hid_evaluate_method(handle, INTEL_HID_DSM_BTNL_FN,
643                                                &dummy)) {
644                         dev_warn(&device->dev,
645                                  "failed to enable HID power button\n");
646                 }
647         }
648
649         device_init_wakeup(&device->dev, true);
650         /*
651          * In order for system wakeup to work, the EC GPE has to be marked as
652          * a wakeup one, so do that here (this setting will persist, but it has
653          * no effect until the wakeup mask is set for the EC GPE).
654          */
655         acpi_ec_mark_gpe_for_wake();
656         return 0;
657
658 err_remove_notify:
659         acpi_remove_notify_handler(handle, ACPI_DEVICE_NOTIFY, notify_handler);
660
661         return err;
662 }
663
664 static int intel_hid_remove(struct platform_device *device)
665 {
666         acpi_handle handle = ACPI_HANDLE(&device->dev);
667
668         device_init_wakeup(&device->dev, false);
669         acpi_remove_notify_handler(handle, ACPI_DEVICE_NOTIFY, notify_handler);
670         intel_hid_set_enable(&device->dev, false);
671         intel_button_array_enable(&device->dev, false);
672
673         /*
674          * Even if we failed to shut off the event stream, we can still
675          * safely detach from the device.
676          */
677         return 0;
678 }
679
680 static struct platform_driver intel_hid_pl_driver = {
681         .driver = {
682                 .name = "intel-hid",
683                 .acpi_match_table = intel_hid_ids,
684                 .pm = &intel_hid_pl_pm_ops,
685         },
686         .probe = intel_hid_probe,
687         .remove = intel_hid_remove,
688 };
689
690 /*
691  * Unfortunately, some laptops provide a _HID="INT33D5" device with
692  * _CID="PNP0C02".  This causes the pnpacpi scan driver to claim the
693  * ACPI node, so no platform device will be created.  The pnpacpi
694  * driver rejects this device in subsequent processing, so no physical
695  * node is created at all.
696  *
697  * As a workaround until the ACPI core figures out how to handle
698  * this corner case, manually ask the ACPI platform device code to
699  * claim the ACPI node.
700  */
701 static acpi_status __init
702 check_acpi_dev(acpi_handle handle, u32 lvl, void *context, void **rv)
703 {
704         const struct acpi_device_id *ids = context;
705         struct acpi_device *dev;
706
707         if (acpi_bus_get_device(handle, &dev) != 0)
708                 return AE_OK;
709
710         if (acpi_match_device_ids(dev, ids) == 0)
711                 if (!IS_ERR_OR_NULL(acpi_create_platform_device(dev, NULL)))
712                         dev_info(&dev->dev,
713                                  "intel-hid: created platform device\n");
714
715         return AE_OK;
716 }
717
718 static int __init intel_hid_init(void)
719 {
720         acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
721                             ACPI_UINT32_MAX, check_acpi_dev, NULL,
722                             (void *)intel_hid_ids, NULL);
723
724         return platform_driver_register(&intel_hid_pl_driver);
725 }
726 module_init(intel_hid_init);
727
728 static void __exit intel_hid_exit(void)
729 {
730         platform_driver_unregister(&intel_hid_pl_driver);
731 }
732 module_exit(intel_hid_exit);