drivers/platform/x86/intel/vbtn.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  *  Intel Virtual Button driver for Windows 8.1+
   4  *
   5  *  Copyright (C) 2016 AceLan Kao <acelan.kao@canonical.com>
   6  *  Copyright (C) 2016 Alex Hung <alex.hung@canonical.com>
   7  */
   8
   9 #include <linux/acpi.h>
  10 #include <linux/cleanup.h>
  11 #include <linux/dmi.h>
  12 #include <linux/input.h>
  13 #include <linux/input/sparse-keymap.h>
  14 #include <linux/kernel.h>
  15 #include <linux/module.h>
  16 #include <linux/mutex.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/suspend.h>
  19 #include "../dual_accel_detect.h"
  20
  21 /* Returned when NOT in tablet mode on some HP Stream x360 11 models */
  22 #define VGBS_TABLET_MODE_FLAG_ALT       0x10
  23 /* When NOT in tablet mode, VGBS returns with the flag 0x40 */
  24 #define VGBS_TABLET_MODE_FLAG           0x40
  25 #define VGBS_DOCK_MODE_FLAG             0x80
  26
  27 #define VGBS_TABLET_MODE_FLAGS (VGBS_TABLET_MODE_FLAG | VGBS_TABLET_MODE_FLAG_ALT)
  28
  29 MODULE_DESCRIPTION("Intel Virtual Button driver");
  30 MODULE_LICENSE("GPL");
  31 MODULE_AUTHOR("AceLan Kao");
  32
  33 static const struct acpi_device_id intel_vbtn_ids[] = {
  34         {"INT33D6", 0},
  35         {"", 0},
  36 };
  37 MODULE_DEVICE_TABLE(acpi, intel_vbtn_ids);
  38
  39 /* In theory, these are HID usages. */
  40 static const struct key_entry intel_vbtn_keymap[] = {
  41         { KE_KEY, 0xC0, { KEY_POWER } },        /* power key press */
  42         { KE_IGNORE, 0xC1, { KEY_POWER } },     /* power key release */
  43         { KE_KEY, 0xC2, { KEY_LEFTMETA } },             /* 'Windows' key press */
  44         { KE_KEY, 0xC3, { KEY_LEFTMETA } },             /* 'Windows' key release */
  45         { KE_KEY, 0xC4, { KEY_VOLUMEUP } },             /* volume-up key press */
  46         { KE_IGNORE, 0xC5, { KEY_VOLUMEUP } },          /* volume-up key release */
  47         { KE_KEY, 0xC6, { KEY_VOLUMEDOWN } },           /* volume-down key press */
  48         { KE_IGNORE, 0xC7, { KEY_VOLUMEDOWN } },        /* volume-down key release */
  49         { KE_KEY,    0xC8, { KEY_ROTATE_LOCK_TOGGLE } },        /* rotate-lock key press */
  50         { KE_KEY,    0xC9, { KEY_ROTATE_LOCK_TOGGLE } },        /* rotate-lock key release */
  51         { KE_END }
  52 };
  53
  54 static const struct key_entry intel_vbtn_switchmap[] = {
  55         /*
  56          * SW_DOCK should only be reported for docking stations, but DSDTs using the
  57          * intel-vbtn code, always seem to use this for 2-in-1s / convertibles and set
  58          * SW_DOCK=1 when in laptop-mode (in tandem with setting SW_TABLET_MODE=0).
  59          * This causes userspace to think the laptop is docked to a port-replicator
  60          * and to disable suspend-on-lid-close, which is undesirable.
  61          * Map the dock events to KEY_IGNORE to avoid this broken SW_DOCK reporting.
  62          */
  63         { KE_IGNORE, 0xCA, { .sw = { SW_DOCK, 1 } } },          /* Docked */
  64         { KE_IGNORE, 0xCB, { .sw = { SW_DOCK, 0 } } },          /* Undocked */
  65         { KE_SW,     0xCC, { .sw = { SW_TABLET_MODE, 1 } } },   /* Tablet */
  66         { KE_SW,     0xCD, { .sw = { SW_TABLET_MODE, 0 } } },   /* Laptop */
  67         { KE_END }
  68 };
  69
  70 struct intel_vbtn_priv {
  71         struct mutex mutex; /* Avoid notify_handler() racing with itself */
  72         struct input_dev *buttons_dev;
  73         struct input_dev *switches_dev;
  74         bool dual_accel;
  75         bool has_buttons;
  76         bool has_switches;
  77         bool wakeup_mode;
  78 };
  79
  80 static void detect_tablet_mode(struct device *dev)
  81 {
  82         struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
  83         acpi_handle handle = ACPI_HANDLE(dev);
  84         unsigned long long vgbs;
  85         acpi_status status;
  86         int m;
  87
  88         status = acpi_evaluate_integer(handle, "VGBS", NULL, &vgbs);
  89         if (ACPI_FAILURE(status))
  90                 return;
  91
  92         m = !(vgbs & VGBS_TABLET_MODE_FLAGS);
  93         input_report_switch(priv->switches_dev, SW_TABLET_MODE, m);
  94         m = (vgbs & VGBS_DOCK_MODE_FLAG) ? 1 : 0;
  95         input_report_switch(priv->switches_dev, SW_DOCK, m);
  96
  97         input_sync(priv->switches_dev);
  98 }
  99
 100 /*
 101  * Note this unconditionally creates the 2 input_dev-s and sets up
 102  * the sparse-keymaps. Only the registration is conditional on
 103  * have_buttons / have_switches. This is done so that the notify
 104  * handler can always call sparse_keymap_entry_from_scancode()
 105  * on the input_dev-s do determine the event type.
 106  */
 107 static int intel_vbtn_input_setup(struct platform_device *device)
 108 {
 109         struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
 110         int ret;
 111
 112         priv->buttons_dev = devm_input_allocate_device(&device->dev);
 113         if (!priv->buttons_dev)
 114                 return -ENOMEM;
 115
 116         ret = sparse_keymap_setup(priv->buttons_dev, intel_vbtn_keymap, NULL);
 117         if (ret)
 118                 return ret;
 119
 120         priv->buttons_dev->dev.parent = &device->dev;
 121         priv->buttons_dev->name = "Intel Virtual Buttons";
 122         priv->buttons_dev->id.bustype = BUS_HOST;
 123
 124         if (priv->has_buttons) {
 125                 ret = input_register_device(priv->buttons_dev);
 126                 if (ret)
 127                         return ret;
 128         }
 129
 130         priv->switches_dev = devm_input_allocate_device(&device->dev);
 131         if (!priv->switches_dev)
 132                 return -ENOMEM;
 133
 134         ret = sparse_keymap_setup(priv->switches_dev, intel_vbtn_switchmap, NULL);
 135         if (ret)
 136                 return ret;
 137
 138         priv->switches_dev->dev.parent = &device->dev;
 139         priv->switches_dev->name = "Intel Virtual Switches";
 140         priv->switches_dev->id.bustype = BUS_HOST;
 141
 142         if (priv->has_switches) {
 143                 ret = input_register_device(priv->switches_dev);
 144                 if (ret)
 145                         return ret;
 146         }
 147
 148         return 0;
 149 }
 150
 151 static void notify_handler(acpi_handle handle, u32 event, void *context)
 152 {
 153         struct platform_device *device = context;
 154         struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
 155         unsigned int val = !(event & 1); /* Even=press, Odd=release */
 156         const struct key_entry *ke, *ke_rel;
 157         struct input_dev *input_dev;
 158         bool autorelease;
 159         int ret;
 160
 161         guard(mutex)(&priv->mutex);
 162
 163         if ((ke = sparse_keymap_entry_from_scancode(priv->buttons_dev, event))) {
 164                 if (!priv->has_buttons) {
 165                         dev_warn(&device->dev, "Warning: received 0x%02x button event on a device without buttons, please report this.\n",
 166                                  event);
 167                         return;
 168                 }
 169                 input_dev = priv->buttons_dev;
 170         } else if ((ke = sparse_keymap_entry_from_scancode(priv->switches_dev, event))) {
 171                 if (!priv->has_switches) {
 172                         /* See dual_accel_detect.h for more info */
 173                         if (priv->dual_accel)
 174                                 return;
 175
 176                         dev_info(&device->dev, "Registering Intel Virtual Switches input-dev after receiving a switch event\n");
 177                         ret = input_register_device(priv->switches_dev);
 178                         if (ret)
 179                                 return;
 180
 181                         priv->has_switches = true;
 182                 }
 183                 input_dev = priv->switches_dev;
 184         } else {
 185                 dev_dbg(&device->dev, "unknown event index 0x%x\n", event);
 186                 return;
 187         }
 188
 189         if (priv->wakeup_mode) {
 190                 pm_wakeup_hard_event(&device->dev);
 191
 192                 /*
 193                  * Skip reporting an evdev event for button wake events,
 194                  * mirroring how the drivers/acpi/button.c code skips this too.
 195                  */
 196                 if (ke->type == KE_KEY)
 197                         return;
 198         }
 199
 200         /*
 201          * Even press events are autorelease if there is no corresponding odd
 202          * release event, or if the odd event is KE_IGNORE.
 203          */
 204         ke_rel = sparse_keymap_entry_from_scancode(input_dev, event | 1);
 205         autorelease = val && (!ke_rel || ke_rel->type == KE_IGNORE);
 206
 207         sparse_keymap_report_event(input_dev, event, val, autorelease);
 208 }
 209
 210 /*
 211  * There are several laptops (non 2-in-1) models out there which support VGBS,
 212  * but simply always return 0, which we translate to SW_TABLET_MODE=1. This in
 213  * turn causes userspace (libinput) to suppress events from the builtin
 214  * keyboard and touchpad, making the laptop essentially unusable.
 215  *
 216  * Since the problem of wrongly reporting SW_TABLET_MODE=1 in combination
 217  * with libinput, leads to a non-usable system. Where as OTOH many people will
 218  * not even notice when SW_TABLET_MODE is not being reported, a DMI based allow
 219  * list is used here. This list mainly matches on the chassis-type of 2-in-1s.
 220  *
 221  * There are also some 2-in-1s which use the intel-vbtn ACPI interface to report
 222  * SW_TABLET_MODE with a chassis-type of 8 ("Portable") or 10 ("Notebook"),
 223  * these are matched on a per model basis, since many normal laptops with a
 224  * possible broken VGBS ACPI-method also use these chassis-types.
 225  */
 226 static const struct dmi_system_id dmi_switches_allow_list[] = {
 227         {
 228                 .matches = {
 229                         DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "31" /* Convertible */),
 230                 },
 231         },
 232         {
 233                 .matches = {
 234                         DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "32" /* Detachable */),
 235                 },
 236         },
 237         {
 238                 .matches = {
 239                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 240                         DMI_MATCH(DMI_PRODUCT_NAME, "Venue 11 Pro 7130"),
 241                 },
 242         },
 243         {
 244                 .matches = {
 245                         DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 246                         DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion 13 x360 PC"),
 247                 },
 248         },
 249         {
 250                 .matches = {
 251                         DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 252                         DMI_MATCH(DMI_PRODUCT_NAME, "Switch SA5-271"),
 253                 },
 254         },
 255         {
 256                 .matches = {
 257                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 258                         DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7352"),
 259                 },
 260         },
 261         {} /* Array terminator */
 262 };
 263
 264 static bool intel_vbtn_has_switches(acpi_handle handle, bool dual_accel)
 265 {
 266         /* See dual_accel_detect.h for more info */
 267         if (dual_accel)
 268                 return false;
 269
 270         if (!dmi_check_system(dmi_switches_allow_list))
 271                 return false;
 272
 273         return acpi_has_method(handle, "VGBS");
 274 }
 275
 276 static int intel_vbtn_probe(struct platform_device *device)
 277 {
 278         acpi_handle handle = ACPI_HANDLE(&device->dev);
 279         bool dual_accel, has_buttons, has_switches;
 280         struct intel_vbtn_priv *priv;
 281         acpi_status status;
 282         int err;
 283
 284         dual_accel = dual_accel_detect();
 285         has_buttons = acpi_has_method(handle, "VBDL");
 286         has_switches = intel_vbtn_has_switches(handle, dual_accel);
 287
 288         if (!has_buttons && !has_switches) {
 289                 dev_warn(&device->dev, "failed to read Intel Virtual Button driver\n");
 290                 return -ENODEV;
 291         }
 292
 293         priv = devm_kzalloc(&device->dev, sizeof(*priv), GFP_KERNEL);
 294         if (!priv)
 295                 return -ENOMEM;
 296         dev_set_drvdata(&device->dev, priv);
 297
 298         err = devm_mutex_init(&device->dev, &priv->mutex);
 299         if (err)
 300                 return err;
 301
 302         priv->dual_accel = dual_accel;
 303         priv->has_buttons = has_buttons;
 304         priv->has_switches = has_switches;
 305
 306         err = intel_vbtn_input_setup(device);
 307         if (err) {
 308                 pr_err("Failed to setup Intel Virtual Button\n");
 309                 return err;
 310         }
 311
 312         status = acpi_install_notify_handler(handle,
 313                                              ACPI_DEVICE_NOTIFY,
 314                                              notify_handler,
 315                                              device);
 316         if (ACPI_FAILURE(status))
 317                 return -EBUSY;
 318
 319         if (has_buttons) {
 320                 status = acpi_evaluate_object(handle, "VBDL", NULL, NULL);
 321                 if (ACPI_FAILURE(status))
 322                         dev_err(&device->dev, "Error VBDL failed with ACPI status %d\n", status);
 323         }
 324         // Check switches after buttons since VBDL may have side effects.
 325         if (has_switches)
 326                 detect_tablet_mode(&device->dev);
 327
 328         device_init_wakeup(&device->dev, true);
 329         /*
 330          * In order for system wakeup to work, the EC GPE has to be marked as
 331          * a wakeup one, so do that here (this setting will persist, but it has
 332          * no effect until the wakeup mask is set for the EC GPE).
 333          */
 334         acpi_ec_mark_gpe_for_wake();
 335         return 0;
 336 }
 337
 338 static void intel_vbtn_remove(struct platform_device *device)
 339 {
 340         acpi_handle handle = ACPI_HANDLE(&device->dev);
 341
 342         device_init_wakeup(&device->dev, false);
 343         acpi_remove_notify_handler(handle, ACPI_DEVICE_NOTIFY, notify_handler);
 344 }
 345
 346 static int intel_vbtn_pm_prepare(struct device *dev)
 347 {
 348         if (device_may_wakeup(dev)) {
 349                 struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
 350
 351                 priv->wakeup_mode = true;
 352         }
 353         return 0;
 354 }
 355
 356 static void intel_vbtn_pm_complete(struct device *dev)
 357 {
 358         struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
 359
 360         priv->wakeup_mode = false;
 361 }
 362
 363 static int intel_vbtn_pm_resume(struct device *dev)
 364 {
 365         struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
 366
 367         intel_vbtn_pm_complete(dev);
 368
 369         if (priv->has_switches)
 370                 detect_tablet_mode(dev);
 371
 372         return 0;
 373 }
 374
 375 static const struct dev_pm_ops intel_vbtn_pm_ops = {
 376         .prepare = intel_vbtn_pm_prepare,
 377         .complete = intel_vbtn_pm_complete,
 378         .resume = intel_vbtn_pm_resume,
 379         .restore = intel_vbtn_pm_resume,
 380         .thaw = intel_vbtn_pm_resume,
 381 };
 382
 383 static struct platform_driver intel_vbtn_pl_driver = {
 384         .driver = {
 385                 .name = "intel-vbtn",
 386                 .acpi_match_table = intel_vbtn_ids,
 387                 .pm = &intel_vbtn_pm_ops,
 388         },
 389         .probe = intel_vbtn_probe,
 390         .remove = intel_vbtn_remove,
 391 };
 392
 393 static acpi_status __init
 394 check_acpi_dev(acpi_handle handle, u32 lvl, void *context, void **rv)
 395 {
 396         const struct acpi_device_id *ids = context;
 397         struct acpi_device *dev = acpi_fetch_acpi_dev(handle);
 398
 399         if (dev && acpi_match_device_ids(dev, ids) == 0)
 400                 if (!IS_ERR_OR_NULL(acpi_create_platform_device(dev, NULL)))
 401                         dev_info(&dev->dev,
 402                                  "intel-vbtn: created platform device\n");
 403
 404         return AE_OK;
 405 }
 406
 407 static int __init intel_vbtn_init(void)
 408 {
 409         acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
 410                             ACPI_UINT32_MAX, check_acpi_dev, NULL,
 411                             (void *)intel_vbtn_ids, NULL);
 412
 413         return platform_driver_register(&intel_vbtn_pl_driver);
 414 }
 415 module_init(intel_vbtn_init);
 416
 417 static void __exit intel_vbtn_exit(void)
 418 {
 419         platform_driver_unregister(&intel_vbtn_pl_driver);
 420 }
 421 module_exit(intel_vbtn_exit);