drivers/platform/x86/lenovo-yogabook.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Platform driver for Lenovo Yoga Book YB1-X90F/L tablets (Android model)
   4  * WMI driver for Lenovo Yoga Book YB1-X91F/L tablets (Windows model)
   5  *
   6  * The keyboard half of the YB1 models can function as both a capacitive
   7  * touch keyboard or as a Wacom digitizer, but not at the same time.
   8  *
   9  * This driver takes care of switching between the 2 functions.
  10  *
  11  * Copyright 2023 Hans de Goede <[email protected]>
  12  */
  13
  14 #include <linux/acpi.h>
  15 #include <linux/gpio/consumer.h>
  16 #include <linux/gpio/machine.h>
  17 #include <linux/i2c.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/leds.h>
  20 #include <linux/module.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/pwm.h>
  23 #include <linux/wmi.h>
  24 #include <linux/workqueue.h>
  25
  26 #define YB_MBTN_EVENT_GUID      "243FEC1D-1963-41C1-8100-06A9D82A94B4"
  27
  28 #define YB_KBD_BL_DEFAULT       128
  29 #define YB_KBD_BL_MAX           255
  30 #define YB_KBD_BL_PWM_PERIOD    13333
  31
  32 #define YB_PDEV_NAME            "yogabook-touch-kbd-digitizer-switch"
  33
  34 /* flags */
  35 enum {
  36         YB_KBD_IS_ON,
  37         YB_DIGITIZER_IS_ON,
  38         YB_DIGITIZER_MODE,
  39         YB_TABLET_MODE,
  40         YB_SUSPENDED,
  41 };
  42
  43 struct yogabook_data {
  44         struct device *dev;
  45         struct acpi_device *kbd_adev;
  46         struct acpi_device *dig_adev;
  47         struct device *kbd_dev;
  48         struct device *dig_dev;
  49         struct led_classdev *pen_led;
  50         struct gpio_desc *pen_touch_event;
  51         struct gpio_desc *kbd_bl_led_enable;
  52         struct gpio_desc *backside_hall_gpio;
  53         struct pwm_device *kbd_bl_pwm;
  54         int (*set_kbd_backlight)(struct yogabook_data *data, uint8_t level);
  55         int pen_touch_irq;
  56         int backside_hall_irq;
  57         struct work_struct work;
  58         struct led_classdev kbd_bl_led;
  59         unsigned long flags;
  60         uint8_t brightness;
  61 };
  62
  63 static void yogabook_work(struct work_struct *work)
  64 {
  65         struct yogabook_data *data = container_of(work, struct yogabook_data, work);
  66         bool kbd_on, digitizer_on;
  67         int r;
  68
  69         if (test_bit(YB_SUSPENDED, &data->flags))
  70                 return;
  71
  72         if (test_bit(YB_TABLET_MODE, &data->flags)) {
  73                 kbd_on = false;
  74                 digitizer_on = false;
  75         } else if (test_bit(YB_DIGITIZER_MODE, &data->flags)) {
  76                 digitizer_on = true;
  77                 kbd_on = false;
  78         } else {
  79                 kbd_on = true;
  80                 digitizer_on = false;
  81         }
  82
  83         if (!kbd_on && test_bit(YB_KBD_IS_ON, &data->flags)) {
  84                 /*
  85                  * Must be done before releasing the keyboard touchscreen driver,
  86                  * so that the keyboard touchscreen dev is still in D0.
  87                  */
  88                 data->set_kbd_backlight(data, 0);
  89                 device_release_driver(data->kbd_dev);
  90                 clear_bit(YB_KBD_IS_ON, &data->flags);
  91         }
  92
  93         if (!digitizer_on && test_bit(YB_DIGITIZER_IS_ON, &data->flags)) {
  94                 led_set_brightness(data->pen_led, LED_OFF);
  95                 device_release_driver(data->dig_dev);
  96                 clear_bit(YB_DIGITIZER_IS_ON, &data->flags);
  97         }
  98
  99         if (kbd_on && !test_bit(YB_KBD_IS_ON, &data->flags)) {
 100                 r = device_reprobe(data->kbd_dev);
 101                 if (r)
 102                         dev_warn(data->dev, "Reprobe of keyboard touchscreen failed: %d\n", r);
 103
 104                 data->set_kbd_backlight(data, data->brightness);
 105                 set_bit(YB_KBD_IS_ON, &data->flags);
 106         }
 107
 108         if (digitizer_on && !test_bit(YB_DIGITIZER_IS_ON, &data->flags)) {
 109                 r = device_reprobe(data->dig_dev);
 110                 if (r)
 111                         dev_warn(data->dev, "Reprobe of digitizer failed: %d\n", r);
 112
 113                 led_set_brightness(data->pen_led, LED_FULL);
 114                 set_bit(YB_DIGITIZER_IS_ON, &data->flags);
 115         }
 116 }
 117
 118 static void yogabook_toggle_digitizer_mode(struct yogabook_data *data)
 119 {
 120         if (test_bit(YB_SUSPENDED, &data->flags))
 121                 return;
 122
 123         if (test_bit(YB_DIGITIZER_MODE, &data->flags))
 124                 clear_bit(YB_DIGITIZER_MODE, &data->flags);
 125         else
 126                 set_bit(YB_DIGITIZER_MODE, &data->flags);
 127
 128         /*
 129          * We are called from the ACPI core and the driver [un]binding which is
 130          * done also needs ACPI functions, use a workqueue to avoid deadlocking.
 131          */
 132         schedule_work(&data->work);
 133 }
 134
 135 static irqreturn_t yogabook_backside_hall_irq(int irq, void *_data)
 136 {
 137         struct yogabook_data *data = _data;
 138
 139         if (gpiod_get_value(data->backside_hall_gpio))
 140                 set_bit(YB_TABLET_MODE, &data->flags);
 141         else
 142                 clear_bit(YB_TABLET_MODE, &data->flags);
 143
 144         schedule_work(&data->work);
 145
 146         return IRQ_HANDLED;
 147 }
 148
 149 #define kbd_led_to_yogabook(cdev) container_of(cdev, struct yogabook_data, kbd_bl_led)
 150
 151 static enum led_brightness kbd_brightness_get(struct led_classdev *cdev)
 152 {
 153         struct yogabook_data *data = kbd_led_to_yogabook(cdev);
 154
 155         return data->brightness;
 156 }
 157
 158 static int kbd_brightness_set(struct led_classdev *cdev,
 159                               enum led_brightness value)
 160 {
 161         struct yogabook_data *data = kbd_led_to_yogabook(cdev);
 162
 163         if ((value < 0) || (value > YB_KBD_BL_MAX))
 164                 return -EINVAL;
 165
 166         data->brightness = value;
 167
 168         if (!test_bit(YB_KBD_IS_ON, &data->flags))
 169                 return 0;
 170
 171         return data->set_kbd_backlight(data, data->brightness);
 172 }
 173
 174 static struct gpiod_lookup_table yogabook_gpios = {
 175         .table = {
 176                 GPIO_LOOKUP("INT33FF:02", 18, "backside_hall_sw", GPIO_ACTIVE_LOW),
 177                 {}
 178         },
 179 };
 180
 181 static struct led_lookup_data yogabook_pen_led = {
 182         .provider = "platform::indicator",
 183         .con_id = "pen-icon-led",
 184 };
 185
 186 static int yogabook_probe(struct device *dev, struct yogabook_data *data,
 187                           const char *kbd_bl_led_name)
 188 {
 189         int r;
 190
 191         data->dev = dev;
 192         data->brightness = YB_KBD_BL_DEFAULT;
 193         set_bit(YB_KBD_IS_ON, &data->flags);
 194         set_bit(YB_DIGITIZER_IS_ON, &data->flags);
 195         INIT_WORK(&data->work, yogabook_work);
 196
 197         yogabook_pen_led.dev_id = dev_name(dev);
 198         led_add_lookup(&yogabook_pen_led);
 199         data->pen_led = devm_led_get(dev, "pen-icon-led");
 200         led_remove_lookup(&yogabook_pen_led);
 201
 202         if (IS_ERR(data->pen_led))
 203                 return dev_err_probe(dev, PTR_ERR(data->pen_led), "Getting pen icon LED\n");
 204
 205         yogabook_gpios.dev_id = dev_name(dev);
 206         gpiod_add_lookup_table(&yogabook_gpios);
 207         data->backside_hall_gpio = devm_gpiod_get(dev, "backside_hall_sw", GPIOD_IN);
 208         gpiod_remove_lookup_table(&yogabook_gpios);
 209
 210         if (IS_ERR(data->backside_hall_gpio))
 211                 return dev_err_probe(dev, PTR_ERR(data->backside_hall_gpio),
 212                                      "Getting backside_hall_sw GPIO\n");
 213
 214         r = gpiod_to_irq(data->backside_hall_gpio);
 215         if (r < 0)
 216                 return dev_err_probe(dev, r, "Getting backside_hall_sw IRQ\n");
 217
 218         data->backside_hall_irq = r;
 219
 220         /* Set default brightness before enabling the IRQ */
 221         data->set_kbd_backlight(data, YB_KBD_BL_DEFAULT);
 222
 223         r = request_irq(data->backside_hall_irq, yogabook_backside_hall_irq,
 224                         IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 225                         "backside_hall_sw", data);
 226         if (r)
 227                 return dev_err_probe(dev, r, "Requesting backside_hall_sw IRQ\n");
 228
 229         schedule_work(&data->work);
 230
 231         data->kbd_bl_led.name = kbd_bl_led_name;
 232         data->kbd_bl_led.brightness_set_blocking = kbd_brightness_set;
 233         data->kbd_bl_led.brightness_get = kbd_brightness_get;
 234         data->kbd_bl_led.max_brightness = YB_KBD_BL_MAX;
 235
 236         r = devm_led_classdev_register(dev, &data->kbd_bl_led);
 237         if (r < 0) {
 238                 dev_err_probe(dev, r, "Registering backlight LED device\n");
 239                 goto error_free_irq;
 240         }
 241
 242         dev_set_drvdata(dev, data);
 243         return 0;
 244
 245 error_free_irq:
 246         free_irq(data->backside_hall_irq, data);
 247         cancel_work_sync(&data->work);
 248         return r;
 249 }
 250
 251 static void yogabook_remove(struct yogabook_data *data)
 252 {
 253         int r = 0;
 254
 255         free_irq(data->backside_hall_irq, data);
 256         cancel_work_sync(&data->work);
 257
 258         if (!test_bit(YB_KBD_IS_ON, &data->flags))
 259                 r |= device_reprobe(data->kbd_dev);
 260
 261         if (!test_bit(YB_DIGITIZER_IS_ON, &data->flags))
 262                 r |= device_reprobe(data->dig_dev);
 263
 264         if (r)
 265                 dev_warn(data->dev, "Reprobe of devices failed\n");
 266 }
 267
 268 static int yogabook_suspend(struct device *dev)
 269 {
 270         struct yogabook_data *data = dev_get_drvdata(dev);
 271
 272         set_bit(YB_SUSPENDED, &data->flags);
 273         flush_work(&data->work);
 274
 275         if (test_bit(YB_KBD_IS_ON, &data->flags))
 276                 data->set_kbd_backlight(data, 0);
 277
 278         return 0;
 279 }
 280
 281 static int yogabook_resume(struct device *dev)
 282 {
 283         struct yogabook_data *data = dev_get_drvdata(dev);
 284
 285         if (test_bit(YB_KBD_IS_ON, &data->flags))
 286                 data->set_kbd_backlight(data, data->brightness);
 287
 288         clear_bit(YB_SUSPENDED, &data->flags);
 289
 290         /* Check for YB_TABLET_MODE changes made during suspend */
 291         schedule_work(&data->work);
 292
 293         return 0;
 294 }
 295
 296 static DEFINE_SIMPLE_DEV_PM_OPS(yogabook_pm_ops, yogabook_suspend, yogabook_resume);
 297
 298 /********** WMI driver code **********/
 299
 300 /*
 301  * To control keyboard backlight, call the method KBLC() of the TCS1 ACPI
 302  * device (Goodix touchpad acts as virtual sensor keyboard).
 303  */
 304 static int yogabook_wmi_set_kbd_backlight(struct yogabook_data *data,
 305                                           uint8_t level)
 306 {
 307         struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
 308         struct acpi_object_list input;
 309         union acpi_object param;
 310         acpi_status status;
 311
 312         dev_dbg(data->dev, "Set KBLC level to %u\n", level);
 313
 314         /* Ensure keyboard touchpad is on before we call KBLC() */
 315         acpi_device_set_power(data->kbd_adev, ACPI_STATE_D0);
 316
 317         input.count = 1;
 318         input.pointer = &param;
 319
 320         param.type = ACPI_TYPE_INTEGER;
 321         param.integer.value = YB_KBD_BL_MAX - level;
 322
 323         status = acpi_evaluate_object(acpi_device_handle(data->kbd_adev), "KBLC",
 324                                       &input, &output);
 325         if (ACPI_FAILURE(status)) {
 326                 dev_err(data->dev, "Failed to call KBLC method: 0x%x\n", status);
 327                 return status;
 328         }
 329
 330         kfree(output.pointer);
 331         return 0;
 332 }
 333
 334 static int yogabook_wmi_probe(struct wmi_device *wdev, const void *context)
 335 {
 336         struct device *dev = &wdev->dev;
 337         struct yogabook_data *data;
 338         int r;
 339
 340         data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 341         if (data == NULL)
 342                 return -ENOMEM;
 343
 344         data->kbd_adev = acpi_dev_get_first_match_dev("GDIX1001", NULL, -1);
 345         if (!data->kbd_adev)
 346                 return dev_err_probe(dev, -ENODEV, "Cannot find the touchpad device in ACPI tables\n");
 347
 348         data->dig_adev = acpi_dev_get_first_match_dev("WCOM0019", NULL, -1);
 349         if (!data->dig_adev) {
 350                 r = dev_err_probe(dev, -ENODEV, "Cannot find the digitizer device in ACPI tables\n");
 351                 goto error_put_devs;
 352         }
 353
 354         data->kbd_dev = get_device(acpi_get_first_physical_node(data->kbd_adev));
 355         if (!data->kbd_dev || !data->kbd_dev->driver) {
 356                 r = -EPROBE_DEFER;
 357                 goto error_put_devs;
 358         }
 359
 360         data->dig_dev = get_device(acpi_get_first_physical_node(data->dig_adev));
 361         if (!data->dig_dev || !data->dig_dev->driver) {
 362                 r = -EPROBE_DEFER;
 363                 goto error_put_devs;
 364         }
 365
 366         data->set_kbd_backlight = yogabook_wmi_set_kbd_backlight;
 367
 368         r = yogabook_probe(dev, data, "ybwmi::kbd_backlight");
 369         if (r)
 370                 goto error_put_devs;
 371
 372         return 0;
 373
 374 error_put_devs:
 375         put_device(data->dig_dev);
 376         put_device(data->kbd_dev);
 377         acpi_dev_put(data->dig_adev);
 378         acpi_dev_put(data->kbd_adev);
 379         return r;
 380 }
 381
 382 static void yogabook_wmi_remove(struct wmi_device *wdev)
 383 {
 384         struct yogabook_data *data = dev_get_drvdata(&wdev->dev);
 385
 386         yogabook_remove(data);
 387
 388         put_device(data->dig_dev);
 389         put_device(data->kbd_dev);
 390         acpi_dev_put(data->dig_adev);
 391         acpi_dev_put(data->kbd_adev);
 392 }
 393
 394 static void yogabook_wmi_notify(struct wmi_device *wdev, union acpi_object *dummy)
 395 {
 396         yogabook_toggle_digitizer_mode(dev_get_drvdata(&wdev->dev));
 397 }
 398
 399 static const struct wmi_device_id yogabook_wmi_id_table[] = {
 400         {
 401                 .guid_string = YB_MBTN_EVENT_GUID,
 402         },
 403         { } /* Terminating entry */
 404 };
 405 MODULE_DEVICE_TABLE(wmi, yogabook_wmi_id_table);
 406
 407 static struct wmi_driver yogabook_wmi_driver = {
 408         .driver = {
 409                 .name = "yogabook-wmi",
 410                 .pm = pm_sleep_ptr(&yogabook_pm_ops),
 411         },
 412         .no_notify_data = true,
 413         .id_table = yogabook_wmi_id_table,
 414         .probe = yogabook_wmi_probe,
 415         .remove = yogabook_wmi_remove,
 416         .notify = yogabook_wmi_notify,
 417 };
 418
 419 /********** platform driver code **********/
 420
 421 static struct gpiod_lookup_table yogabook_pdev_gpios = {
 422         .dev_id = YB_PDEV_NAME,
 423         .table = {
 424                 GPIO_LOOKUP("INT33FF:00", 95, "pen_touch_event", GPIO_ACTIVE_HIGH),
 425                 GPIO_LOOKUP("INT33FF:03", 52, "enable_keyboard_led", GPIO_ACTIVE_HIGH),
 426                 {}
 427         },
 428 };
 429
 430 static int yogabook_pdev_set_kbd_backlight(struct yogabook_data *data, u8 level)
 431 {
 432         struct pwm_state state = {
 433                 .period = YB_KBD_BL_PWM_PERIOD,
 434                 .duty_cycle = YB_KBD_BL_PWM_PERIOD * level / YB_KBD_BL_MAX,
 435                 .enabled = level,
 436         };
 437
 438         pwm_apply_state(data->kbd_bl_pwm, &state);
 439         gpiod_set_value(data->kbd_bl_led_enable, level ? 1 : 0);
 440         return 0;
 441 }
 442
 443 static irqreturn_t yogabook_pen_touch_irq(int irq, void *data)
 444 {
 445         yogabook_toggle_digitizer_mode(data);
 446         return IRQ_HANDLED;
 447 }
 448
 449 static int yogabook_pdev_probe(struct platform_device *pdev)
 450 {
 451         struct device *dev = &pdev->dev;
 452         struct yogabook_data *data;
 453         int r;
 454
 455         data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 456         if (data == NULL)
 457                 return -ENOMEM;
 458
 459         data->kbd_dev = bus_find_device_by_name(&i2c_bus_type, NULL, "i2c-goodix_ts");
 460         if (!data->kbd_dev || !data->kbd_dev->driver) {
 461                 r = -EPROBE_DEFER;
 462                 goto error_put_devs;
 463         }
 464
 465         data->dig_dev = bus_find_device_by_name(&i2c_bus_type, NULL, "i2c-wacom");
 466         if (!data->dig_dev || !data->dig_dev->driver) {
 467                 r = -EPROBE_DEFER;
 468                 goto error_put_devs;
 469         }
 470
 471         gpiod_add_lookup_table(&yogabook_pdev_gpios);
 472         data->pen_touch_event = devm_gpiod_get(dev, "pen_touch_event", GPIOD_IN);
 473         data->kbd_bl_led_enable = devm_gpiod_get(dev, "enable_keyboard_led", GPIOD_OUT_HIGH);
 474         gpiod_remove_lookup_table(&yogabook_pdev_gpios);
 475
 476         if (IS_ERR(data->pen_touch_event)) {
 477                 r = dev_err_probe(dev, PTR_ERR(data->pen_touch_event),
 478                                   "Getting pen_touch_event GPIO\n");
 479                 goto error_put_devs;
 480         }
 481
 482         if (IS_ERR(data->kbd_bl_led_enable)) {
 483                 r = dev_err_probe(dev, PTR_ERR(data->kbd_bl_led_enable),
 484                                   "Getting enable_keyboard_led GPIO\n");
 485                 goto error_put_devs;
 486         }
 487
 488         data->kbd_bl_pwm = devm_pwm_get(dev, "pwm_soc_lpss_2");
 489         if (IS_ERR(data->kbd_bl_pwm)) {
 490                 r = dev_err_probe(dev, PTR_ERR(data->kbd_bl_pwm),
 491                                   "Getting keyboard backlight PWM\n");
 492                 goto error_put_devs;
 493         }
 494
 495         r = gpiod_to_irq(data->pen_touch_event);
 496         if (r < 0) {
 497                 dev_err_probe(dev, r, "Getting pen_touch_event IRQ\n");
 498                 goto error_put_devs;
 499         }
 500         data->pen_touch_irq = r;
 501
 502         r = request_irq(data->pen_touch_irq, yogabook_pen_touch_irq, IRQF_TRIGGER_FALLING,
 503                         "pen_touch_event", data);
 504         if (r) {
 505                 dev_err_probe(dev, r, "Requesting pen_touch_event IRQ\n");
 506                 goto error_put_devs;
 507         }
 508
 509         data->set_kbd_backlight = yogabook_pdev_set_kbd_backlight;
 510
 511         r = yogabook_probe(dev, data, "yogabook::kbd_backlight");
 512         if (r)
 513                 goto error_free_irq;
 514
 515         return 0;
 516
 517 error_free_irq:
 518         free_irq(data->pen_touch_irq, data);
 519         cancel_work_sync(&data->work);
 520 error_put_devs:
 521         put_device(data->dig_dev);
 522         put_device(data->kbd_dev);
 523         return r;
 524 }
 525
 526 static void yogabook_pdev_remove(struct platform_device *pdev)
 527 {
 528         struct yogabook_data *data = platform_get_drvdata(pdev);
 529
 530         yogabook_remove(data);
 531         free_irq(data->pen_touch_irq, data);
 532         cancel_work_sync(&data->work);
 533         put_device(data->dig_dev);
 534         put_device(data->kbd_dev);
 535 }
 536
 537 static struct platform_driver yogabook_pdev_driver = {
 538         .probe = yogabook_pdev_probe,
 539         .remove_new = yogabook_pdev_remove,
 540         .driver = {
 541                 .name = YB_PDEV_NAME,
 542                 .pm = pm_sleep_ptr(&yogabook_pm_ops),
 543         },
 544 };
 545
 546 static int __init yogabook_module_init(void)
 547 {
 548         int r;
 549
 550         r = wmi_driver_register(&yogabook_wmi_driver);
 551         if (r)
 552                 return r;
 553
 554         r = platform_driver_register(&yogabook_pdev_driver);
 555         if (r)
 556                 wmi_driver_unregister(&yogabook_wmi_driver);
 557
 558         return r;
 559 }
 560
 561 static void __exit yogabook_module_exit(void)
 562 {
 563         platform_driver_unregister(&yogabook_pdev_driver);
 564         wmi_driver_unregister(&yogabook_wmi_driver);
 565 }
 566
 567 module_init(yogabook_module_init);
 568 module_exit(yogabook_module_exit);
 569
 570 MODULE_ALIAS("platform:" YB_PDEV_NAME);
 571 MODULE_AUTHOR("Yauhen Kharuzhy");
 572 MODULE_DESCRIPTION("Lenovo Yoga Book driver");
 573 MODULE_LICENSE("GPL v2");