drivers/platform/loongarch/loongson-laptop.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  Generic Loongson processor based LAPTOP/ALL-IN-ONE driver
   4  *
   5  *  Jianmin Lv <lvjianmin@loongson.cn>
   6  *  Huacai Chen <chenhuacai@loongson.cn>
   7  *
   8  * Copyright (C) 2022 Loongson Technology Corporation Limited
   9  */
  10
  11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  12
  13 #include <linux/init.h>
  14 #include <linux/kernel.h>
  15 #include <linux/module.h>
  16 #include <linux/acpi.h>
  17 #include <linux/backlight.h>
  18 #include <linux/device.h>
  19 #include <linux/input.h>
  20 #include <linux/input/sparse-keymap.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/string.h>
  23 #include <linux/types.h>
  24 #include <acpi/video.h>
  25
  26 /* 1. Driver-wide structs and misc. variables */
  27
  28 /* ACPI HIDs */
  29 #define LOONGSON_ACPI_EC_HID    "PNP0C09"
  30 #define LOONGSON_ACPI_HKEY_HID  "LOON0000"
  31
  32 #define ACPI_LAPTOP_NAME "loongson-laptop"
  33 #define ACPI_LAPTOP_ACPI_EVENT_PREFIX "loongson"
  34
  35 #define MAX_ACPI_ARGS                   3
  36 #define GENERIC_HOTKEY_MAP_MAX          64
  37
  38 #define GENERIC_EVENT_TYPE_OFF          12
  39 #define GENERIC_EVENT_TYPE_MASK         0xF000
  40 #define GENERIC_EVENT_CODE_MASK         0x0FFF
  41
  42 struct generic_sub_driver {
  43         u32 type;
  44         char *name;
  45         acpi_handle *handle;
  46         struct acpi_device *device;
  47         struct platform_driver *driver;
  48         int (*init)(struct generic_sub_driver *sub_driver);
  49         void (*notify)(struct generic_sub_driver *sub_driver, u32 event);
  50         u8 acpi_notify_installed;
  51 };
  52
  53 static u32 input_device_registered;
  54 static struct input_dev *generic_inputdev;
  55
  56 static acpi_handle hotkey_handle;
  57 static struct key_entry hotkey_keycode_map[GENERIC_HOTKEY_MAP_MAX];
  58
  59 int loongson_laptop_turn_on_backlight(void);
  60 int loongson_laptop_turn_off_backlight(void);
  61 static int loongson_laptop_backlight_update(struct backlight_device *bd);
  62
  63 /* 2. ACPI Helpers and device model */
  64
  65 static int acpi_evalf(acpi_handle handle, int *res, char *method, char *fmt, ...)
  66 {
  67         char res_type;
  68         char *fmt0 = fmt;
  69         va_list ap;
  70         int success, quiet;
  71         acpi_status status;
  72         struct acpi_object_list params;
  73         struct acpi_buffer result, *resultp;
  74         union acpi_object in_objs[MAX_ACPI_ARGS], out_obj;
  75
  76         if (!*fmt) {
  77                 pr_err("acpi_evalf() called with empty format\n");
  78                 return 0;
  79         }
  80
  81         if (*fmt == 'q') {
  82                 quiet = 1;
  83                 fmt++;
  84         } else
  85                 quiet = 0;
  86
  87         res_type = *(fmt++);
  88
  89         params.count = 0;
  90         params.pointer = &in_objs[0];
  91
  92         va_start(ap, fmt);
  93         while (*fmt) {
  94                 char c = *(fmt++);
  95                 switch (c) {
  96                 case 'd':       /* int */
  97                         in_objs[params.count].integer.value = va_arg(ap, int);
  98                         in_objs[params.count++].type = ACPI_TYPE_INTEGER;
  99                         break;
 100                         /* add more types as needed */
 101                 default:
 102                         pr_err("acpi_evalf() called with invalid format character '%c'\n", c);
 103                         va_end(ap);
 104                         return 0;
 105                 }
 106         }
 107         va_end(ap);
 108
 109         if (res_type != 'v') {
 110                 result.length = sizeof(out_obj);
 111                 result.pointer = &out_obj;
 112                 resultp = &result;
 113         } else
 114                 resultp = NULL;
 115
 116         status = acpi_evaluate_object(handle, method, &params, resultp);
 117
 118         switch (res_type) {
 119         case 'd':               /* int */
 120                 success = (status == AE_OK && out_obj.type == ACPI_TYPE_INTEGER);
 121                 if (success && res)
 122                         *res = out_obj.integer.value;
 123                 break;
 124         case 'v':               /* void */
 125                 success = status == AE_OK;
 126                 break;
 127                 /* add more types as needed */
 128         default:
 129                 pr_err("acpi_evalf() called with invalid format character '%c'\n", res_type);
 130                 return 0;
 131         }
 132
 133         if (!success && !quiet)
 134                 pr_err("acpi_evalf(%s, %s, ...) failed: %s\n",
 135                        method, fmt0, acpi_format_exception(status));
 136
 137         return success;
 138 }
 139
 140 static int hotkey_status_get(int *status)
 141 {
 142         if (!acpi_evalf(hotkey_handle, status, "GSWS", "d"))
 143                 return -EIO;
 144
 145         return 0;
 146 }
 147
 148 static void dispatch_acpi_notify(acpi_handle handle, u32 event, void *data)
 149 {
 150         struct generic_sub_driver *sub_driver = data;
 151
 152         if (!sub_driver || !sub_driver->notify)
 153                 return;
 154         sub_driver->notify(sub_driver, event);
 155 }
 156
 157 static int __init setup_acpi_notify(struct generic_sub_driver *sub_driver)
 158 {
 159         acpi_status status;
 160
 161         if (!*sub_driver->handle)
 162                 return 0;
 163
 164         sub_driver->device = acpi_fetch_acpi_dev(*sub_driver->handle);
 165         if (!sub_driver->device) {
 166                 pr_err("acpi_fetch_acpi_dev(%s) failed\n", sub_driver->name);
 167                 return -ENODEV;
 168         }
 169
 170         sub_driver->device->driver_data = sub_driver;
 171         sprintf(acpi_device_class(sub_driver->device), "%s/%s",
 172                 ACPI_LAPTOP_ACPI_EVENT_PREFIX, sub_driver->name);
 173
 174         status = acpi_install_notify_handler(*sub_driver->handle,
 175                         sub_driver->type, dispatch_acpi_notify, sub_driver);
 176         if (ACPI_FAILURE(status)) {
 177                 if (status == AE_ALREADY_EXISTS) {
 178                         pr_notice("Another device driver is already "
 179                                   "handling %s events\n", sub_driver->name);
 180                 } else {
 181                         pr_err("acpi_install_notify_handler(%s) failed: %s\n",
 182                                sub_driver->name, acpi_format_exception(status));
 183                 }
 184                 return -ENODEV;
 185         }
 186         sub_driver->acpi_notify_installed = 1;
 187
 188         return 0;
 189 }
 190
 191 static int loongson_hotkey_suspend(struct device *dev)
 192 {
 193         return 0;
 194 }
 195
 196 static int loongson_hotkey_resume(struct device *dev)
 197 {
 198         int status = 0;
 199         struct key_entry ke;
 200         struct backlight_device *bd;
 201
 202         bd = backlight_device_get_by_type(BACKLIGHT_PLATFORM);
 203         if (bd) {
 204                 loongson_laptop_backlight_update(bd) ?
 205                 pr_warn("Loongson_backlight: resume brightness failed") :
 206                 pr_info("Loongson_backlight: resume brightness %d\n", bd->props.brightness);
 207         }
 208
 209         /*
 210          * Only if the firmware supports SW_LID event model, we can handle the
 211          * event. This is for the consideration of development board without EC.
 212          */
 213         if (test_bit(SW_LID, generic_inputdev->swbit)) {
 214                 if (hotkey_status_get(&status) < 0)
 215                         return -EIO;
 216                 /*
 217                  * The input device sw element records the last lid status.
 218                  * When the system is awakened by other wake-up sources,
 219                  * the lid event will also be reported. The judgment of
 220                  * adding SW_LID bit which in sw element can avoid this
 221                  * case.
 222                  *
 223                  * Input system will drop lid event when current lid event
 224                  * value and last lid status in the same. So laptop driver
 225                  * doesn't report repeated events.
 226                  *
 227                  * Lid status is generally 0, but hardware exception is
 228                  * considered. So add lid status confirmation.
 229                  */
 230                 if (test_bit(SW_LID, generic_inputdev->sw) && !(status & (1 << SW_LID))) {
 231                         ke.type = KE_SW;
 232                         ke.sw.value = (u8)status;
 233                         ke.sw.code = SW_LID;
 234                         sparse_keymap_report_entry(generic_inputdev, &ke, 1, true);
 235                 }
 236         }
 237
 238         return 0;
 239 }
 240
 241 static DEFINE_SIMPLE_DEV_PM_OPS(loongson_hotkey_pm,
 242                 loongson_hotkey_suspend, loongson_hotkey_resume);
 243
 244 static int loongson_hotkey_probe(struct platform_device *pdev)
 245 {
 246         hotkey_handle = ACPI_HANDLE(&pdev->dev);
 247
 248         if (!hotkey_handle)
 249                 return -ENODEV;
 250
 251         return 0;
 252 }
 253
 254 static const struct acpi_device_id loongson_device_ids[] = {
 255         {LOONGSON_ACPI_HKEY_HID, 0},
 256         {"", 0},
 257 };
 258 MODULE_DEVICE_TABLE(acpi, loongson_device_ids);
 259
 260 static struct platform_driver loongson_hotkey_driver = {
 261         .probe          = loongson_hotkey_probe,
 262         .driver         = {
 263                 .name   = "loongson-hotkey",
 264                 .owner  = THIS_MODULE,
 265                 .pm     = pm_ptr(&loongson_hotkey_pm),
 266                 .acpi_match_table = loongson_device_ids,
 267         },
 268 };
 269
 270 static int hotkey_map(void)
 271 {
 272         u32 index;
 273         acpi_status status;
 274         struct acpi_buffer buf;
 275         union acpi_object *pack;
 276
 277         buf.length = ACPI_ALLOCATE_BUFFER;
 278         status = acpi_evaluate_object_typed(hotkey_handle, "KMAP", NULL, &buf, ACPI_TYPE_PACKAGE);
 279         if (status != AE_OK) {
 280                 pr_err("ACPI exception: %s\n", acpi_format_exception(status));
 281                 return -1;
 282         }
 283         pack = buf.pointer;
 284         for (index = 0; index < pack->package.count; index++) {
 285                 union acpi_object *element, *sub_pack;
 286
 287                 sub_pack = &pack->package.elements[index];
 288
 289                 element = &sub_pack->package.elements[0];
 290                 hotkey_keycode_map[index].type = element->integer.value;
 291                 element = &sub_pack->package.elements[1];
 292                 hotkey_keycode_map[index].code = element->integer.value;
 293                 element = &sub_pack->package.elements[2];
 294                 hotkey_keycode_map[index].keycode = element->integer.value;
 295         }
 296
 297         return 0;
 298 }
 299
 300 static int hotkey_backlight_set(bool enable)
 301 {
 302         if (!acpi_evalf(hotkey_handle, NULL, "VCBL", "vd", enable ? 1 : 0))
 303                 return -EIO;
 304
 305         return 0;
 306 }
 307
 308 static int ec_get_brightness(void)
 309 {
 310         int status = 0;
 311
 312         if (!hotkey_handle)
 313                 return -ENXIO;
 314
 315         if (!acpi_evalf(hotkey_handle, &status, "ECBG", "d"))
 316                 return -EIO;
 317
 318         return status;
 319 }
 320
 321 static int ec_set_brightness(int level)
 322 {
 323
 324         int ret = 0;
 325
 326         if (!hotkey_handle)
 327                 return -ENXIO;
 328
 329         if (!acpi_evalf(hotkey_handle, NULL, "ECBS", "vd", level))
 330                 ret = -EIO;
 331
 332         return ret;
 333 }
 334
 335 static int ec_backlight_level(u8 level)
 336 {
 337         int status = 0;
 338
 339         if (!hotkey_handle)
 340                 return -ENXIO;
 341
 342         if (!acpi_evalf(hotkey_handle, &status, "ECLL", "d"))
 343                 return -EIO;
 344
 345         if ((status < 0) || (level > status))
 346                 return status;
 347
 348         if (!acpi_evalf(hotkey_handle, &status, "ECSL", "d"))
 349                 return -EIO;
 350
 351         if ((status < 0) || (level < status))
 352                 return status;
 353
 354         return level;
 355 }
 356
 357 static int loongson_laptop_backlight_update(struct backlight_device *bd)
 358 {
 359         int lvl = ec_backlight_level(bd->props.brightness);
 360
 361         if (lvl < 0)
 362                 return -EIO;
 363         if (ec_set_brightness(lvl))
 364                 return -EIO;
 365
 366         return 0;
 367 }
 368
 369 static int loongson_laptop_get_brightness(struct backlight_device *bd)
 370 {
 371         int level;
 372
 373         level = ec_get_brightness();
 374         if (level < 0)
 375                 return -EIO;
 376
 377         return level;
 378 }
 379
 380 static const struct backlight_ops backlight_laptop_ops = {
 381         .update_status = loongson_laptop_backlight_update,
 382         .get_brightness = loongson_laptop_get_brightness,
 383 };
 384
 385 static int laptop_backlight_register(void)
 386 {
 387         int status = 0;
 388         struct backlight_properties props;
 389
 390         memset(&props, 0, sizeof(props));
 391
 392         if (!acpi_evalf(hotkey_handle, &status, "ECLL", "d"))
 393                 return -EIO;
 394
 395         props.brightness = 1;
 396         props.max_brightness = status;
 397         props.type = BACKLIGHT_PLATFORM;
 398
 399         backlight_device_register("loongson_laptop",
 400                                 NULL, NULL, &backlight_laptop_ops, &props);
 401
 402         return 0;
 403 }
 404
 405 int loongson_laptop_turn_on_backlight(void)
 406 {
 407         int status;
 408         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 409         struct acpi_object_list args = { 1, &arg0 };
 410
 411         arg0.integer.value = 1;
 412         status = acpi_evaluate_object(NULL, "\\BLSW", &args, NULL);
 413         if (ACPI_FAILURE(status)) {
 414                 pr_info("Loongson lvds error: 0x%x\n", status);
 415                 return -ENODEV;
 416         }
 417
 418         return 0;
 419 }
 420
 421 int loongson_laptop_turn_off_backlight(void)
 422 {
 423         int status;
 424         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 425         struct acpi_object_list args = { 1, &arg0 };
 426
 427         arg0.integer.value = 0;
 428         status = acpi_evaluate_object(NULL, "\\BLSW", &args, NULL);
 429         if (ACPI_FAILURE(status)) {
 430                 pr_info("Loongson lvds error: 0x%x\n", status);
 431                 return -ENODEV;
 432         }
 433
 434         return 0;
 435 }
 436
 437 static int __init event_init(struct generic_sub_driver *sub_driver)
 438 {
 439         int ret;
 440
 441         ret = hotkey_map();
 442         if (ret < 0) {
 443                 pr_err("Failed to parse keymap from DSDT\n");
 444                 return ret;
 445         }
 446
 447         ret = sparse_keymap_setup(generic_inputdev, hotkey_keycode_map, NULL);
 448         if (ret < 0) {
 449                 pr_err("Failed to setup input device keymap\n");
 450                 input_free_device(generic_inputdev);
 451                 generic_inputdev = NULL;
 452
 453                 return ret;
 454         }
 455
 456         /*
 457          * This hotkey driver handle backlight event when
 458          * acpi_video_get_backlight_type() gets acpi_backlight_vendor
 459          */
 460         if (acpi_video_get_backlight_type() == acpi_backlight_vendor)
 461                 hotkey_backlight_set(true);
 462         else
 463                 hotkey_backlight_set(false);
 464
 465         pr_info("ACPI: enabling firmware HKEY event interface...\n");
 466
 467         return ret;
 468 }
 469
 470 static void event_notify(struct generic_sub_driver *sub_driver, u32 event)
 471 {
 472         int type, scan_code;
 473         struct key_entry *ke = NULL;
 474
 475         scan_code = event & GENERIC_EVENT_CODE_MASK;
 476         type = (event & GENERIC_EVENT_TYPE_MASK) >> GENERIC_EVENT_TYPE_OFF;
 477         ke = sparse_keymap_entry_from_scancode(generic_inputdev, scan_code);
 478         if (ke) {
 479                 if (type == KE_SW) {
 480                         int status = 0;
 481
 482                         if (hotkey_status_get(&status) < 0)
 483                                 return;
 484
 485                         ke->sw.value = !!(status & (1 << ke->sw.code));
 486                 }
 487                 sparse_keymap_report_entry(generic_inputdev, ke, 1, true);
 488         }
 489 }
 490
 491 /* 3. Infrastructure */
 492
 493 static void generic_subdriver_exit(struct generic_sub_driver *sub_driver);
 494
 495 static int __init generic_subdriver_init(struct generic_sub_driver *sub_driver)
 496 {
 497         int ret;
 498
 499         if (!sub_driver || !sub_driver->driver)
 500                 return -EINVAL;
 501
 502         ret = platform_driver_register(sub_driver->driver);
 503         if (ret)
 504                 return -EINVAL;
 505
 506         if (sub_driver->init) {
 507                 ret = sub_driver->init(sub_driver);
 508                 if (ret)
 509                         goto err_out;
 510         }
 511
 512         if (sub_driver->notify) {
 513                 ret = setup_acpi_notify(sub_driver);
 514                 if (ret == -ENODEV) {
 515                         ret = 0;
 516                         goto err_out;
 517                 }
 518                 if (ret < 0)
 519                         goto err_out;
 520         }
 521
 522         return 0;
 523
 524 err_out:
 525         generic_subdriver_exit(sub_driver);
 526         return ret;
 527 }
 528
 529 static void generic_subdriver_exit(struct generic_sub_driver *sub_driver)
 530 {
 531
 532         if (sub_driver->acpi_notify_installed) {
 533                 acpi_remove_notify_handler(*sub_driver->handle,
 534                                            sub_driver->type, dispatch_acpi_notify);
 535                 sub_driver->acpi_notify_installed = 0;
 536         }
 537         platform_driver_unregister(sub_driver->driver);
 538 }
 539
 540 static struct generic_sub_driver generic_sub_drivers[] __refdata = {
 541         {
 542                 .name = "hotkey",
 543                 .init = event_init,
 544                 .notify = event_notify,
 545                 .handle = &hotkey_handle,
 546                 .type = ACPI_DEVICE_NOTIFY,
 547                 .driver = &loongson_hotkey_driver,
 548         },
 549 };
 550
 551 static int __init generic_acpi_laptop_init(void)
 552 {
 553         bool ec_found;
 554         int i, ret, status;
 555
 556         if (acpi_disabled)
 557                 return -ENODEV;
 558
 559         /* The EC device is required */
 560         ec_found = acpi_dev_found(LOONGSON_ACPI_EC_HID);
 561         if (!ec_found)
 562                 return -ENODEV;
 563
 564         /* Enable SCI for EC */
 565         acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
 566
 567         generic_inputdev = input_allocate_device();
 568         if (!generic_inputdev) {
 569                 pr_err("Unable to allocate input device\n");
 570                 return -ENOMEM;
 571         }
 572
 573         /* Prepare input device, but don't register */
 574         generic_inputdev->name =
 575                 "Loongson Generic Laptop/All-in-One Extra Buttons";
 576         generic_inputdev->phys = ACPI_LAPTOP_NAME "/input0";
 577         generic_inputdev->id.bustype = BUS_HOST;
 578         generic_inputdev->dev.parent = NULL;
 579
 580         /* Init subdrivers */
 581         for (i = 0; i < ARRAY_SIZE(generic_sub_drivers); i++) {
 582                 ret = generic_subdriver_init(&generic_sub_drivers[i]);
 583                 if (ret < 0) {
 584                         input_free_device(generic_inputdev);
 585                         while (--i >= 0)
 586                                 generic_subdriver_exit(&generic_sub_drivers[i]);
 587                         return ret;
 588                 }
 589         }
 590
 591         ret = input_register_device(generic_inputdev);
 592         if (ret < 0) {
 593                 input_free_device(generic_inputdev);
 594                 while (--i >= 0)
 595                         generic_subdriver_exit(&generic_sub_drivers[i]);
 596                 pr_err("Unable to register input device\n");
 597                 return ret;
 598         }
 599
 600         input_device_registered = 1;
 601
 602         if (acpi_evalf(hotkey_handle, &status, "ECBG", "d")) {
 603                 pr_info("Loongson Laptop used, init brightness is 0x%x\n", status);
 604                 ret = laptop_backlight_register();
 605                 if (ret < 0)
 606                         pr_err("Loongson Laptop: laptop-backlight device register failed\n");
 607         }
 608
 609         return 0;
 610 }
 611
 612 static void __exit generic_acpi_laptop_exit(void)
 613 {
 614         if (generic_inputdev) {
 615                 if (input_device_registered)
 616                         input_unregister_device(generic_inputdev);
 617                 else
 618                         input_free_device(generic_inputdev);
 619         }
 620 }
 621
 622 module_init(generic_acpi_laptop_init);
 623 module_exit(generic_acpi_laptop_exit);
 624
 625 MODULE_AUTHOR("Jianmin Lv <lvjianmin@loongson.cn>");
 626 MODULE_AUTHOR("Huacai Chen <chenhuacai@loongson.cn>");
 627 MODULE_DESCRIPTION("Loongson Laptop/All-in-One ACPI Driver");
 628 MODULE_LICENSE("GPL");