drivers/soc/aspeed/aspeed-uart-routing.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (c) 2018 Google LLC
   4  * Copyright (c) 2021 Aspeed Technology Inc.
   5  */
   6 #include <linux/device.h>
   7 #include <linux/module.h>
   8 #include <linux/of_device.h>
   9 #include <linux/of_platform.h>
  10 #include <linux/mfd/syscon.h>
  11 #include <linux/regmap.h>
  12 #include <linux/platform_device.h>
  13
  14 /* register offsets */
  15 #define HICR9   0x98
  16 #define HICRA   0x9c
  17
  18 /* attributes options */
  19 #define UART_ROUTING_IO1        "io1"
  20 #define UART_ROUTING_IO2        "io2"
  21 #define UART_ROUTING_IO3        "io3"
  22 #define UART_ROUTING_IO4        "io4"
  23 #define UART_ROUTING_IO5        "io5"
  24 #define UART_ROUTING_IO6        "io6"
  25 #define UART_ROUTING_IO10       "io10"
  26 #define UART_ROUTING_UART1      "uart1"
  27 #define UART_ROUTING_UART2      "uart2"
  28 #define UART_ROUTING_UART3      "uart3"
  29 #define UART_ROUTING_UART4      "uart4"
  30 #define UART_ROUTING_UART5      "uart5"
  31 #define UART_ROUTING_UART6      "uart6"
  32 #define UART_ROUTING_UART10     "uart10"
  33 #define UART_ROUTING_RES        "reserved"
  34
  35 struct aspeed_uart_routing {
  36         struct regmap *map;
  37         struct attribute_group const *attr_grp;
  38 };
  39
  40 struct aspeed_uart_routing_selector {
  41         struct device_attribute dev_attr;
  42         uint8_t reg;
  43         uint8_t mask;
  44         uint8_t shift;
  45         const char *const options[];
  46 };
  47
  48 #define to_routing_selector(_dev_attr)                                  \
  49         container_of(_dev_attr, struct aspeed_uart_routing_selector, dev_attr)
  50
  51 static ssize_t aspeed_uart_routing_show(struct device *dev,
  52                                         struct device_attribute *attr,
  53                                         char *buf);
  54
  55 static ssize_t aspeed_uart_routing_store(struct device *dev,
  56                                          struct device_attribute *attr,
  57                                          const char *buf, size_t count);
  58
  59 #define ROUTING_ATTR(_name) {                                   \
  60         .attr = {.name = _name,                                 \
  61                  .mode = VERIFY_OCTAL_PERMISSIONS(0644) },      \
  62         .show = aspeed_uart_routing_show,                       \
  63         .store = aspeed_uart_routing_store,                     \
  64 }
  65
  66 /* routing selector for AST25xx */
  67 static struct aspeed_uart_routing_selector ast2500_io6_sel = {
  68         .dev_attr = ROUTING_ATTR(UART_ROUTING_IO6),
  69         .reg = HICR9,
  70         .shift = 8,
  71         .mask = 0xf,
  72         .options = {
  73                     UART_ROUTING_UART1,
  74                     UART_ROUTING_UART2,
  75                     UART_ROUTING_UART3,
  76                     UART_ROUTING_UART4,
  77                     UART_ROUTING_UART5,
  78                     UART_ROUTING_IO1,
  79                     UART_ROUTING_IO2,
  80                     UART_ROUTING_IO3,
  81                     UART_ROUTING_IO4,
  82                     UART_ROUTING_IO5,
  83                     NULL,
  84                     },
  85 };
  86
  87 static struct aspeed_uart_routing_selector ast2500_uart5_sel = {
  88         .dev_attr = ROUTING_ATTR(UART_ROUTING_UART5),
  89         .reg = HICRA,
  90         .shift = 28,
  91         .mask = 0xf,
  92         .options = {
  93                     UART_ROUTING_IO5,
  94                     UART_ROUTING_IO1,
  95                     UART_ROUTING_IO2,
  96                     UART_ROUTING_IO3,
  97                     UART_ROUTING_IO4,
  98                     UART_ROUTING_UART1,
  99                     UART_ROUTING_UART2,
 100                     UART_ROUTING_UART3,
 101                     UART_ROUTING_UART4,
 102                     UART_ROUTING_IO6,
 103                     NULL,
 104                     },
 105 };
 106
 107 static struct aspeed_uart_routing_selector ast2500_uart4_sel = {
 108         .dev_attr = ROUTING_ATTR(UART_ROUTING_UART4),
 109         .reg = HICRA,
 110         .shift = 25,
 111         .mask = 0x7,
 112         .options = {
 113                     UART_ROUTING_IO4,
 114                     UART_ROUTING_IO1,
 115                     UART_ROUTING_IO2,
 116                     UART_ROUTING_IO3,
 117                     UART_ROUTING_UART1,
 118                     UART_ROUTING_UART2,
 119                     UART_ROUTING_UART3,
 120                     UART_ROUTING_IO6,
 121                     NULL,
 122         },
 123 };
 124
 125 static struct aspeed_uart_routing_selector ast2500_uart3_sel = {
 126         .dev_attr = ROUTING_ATTR(UART_ROUTING_UART3),
 127         .reg = HICRA,
 128         .shift = 22,
 129         .mask = 0x7,
 130         .options = {
 131                     UART_ROUTING_IO3,
 132                     UART_ROUTING_IO4,
 133                     UART_ROUTING_IO1,
 134                     UART_ROUTING_IO2,
 135                     UART_ROUTING_UART4,
 136                     UART_ROUTING_UART1,
 137                     UART_ROUTING_UART2,
 138                     UART_ROUTING_IO6,
 139                     NULL,
 140                     },
 141 };
 142
 143 static struct aspeed_uart_routing_selector ast2500_uart2_sel = {
 144         .dev_attr = ROUTING_ATTR(UART_ROUTING_UART2),
 145         .reg = HICRA,
 146         .shift = 19,
 147         .mask = 0x7,
 148         .options = {
 149                     UART_ROUTING_IO2,
 150                     UART_ROUTING_IO3,
 151                     UART_ROUTING_IO4,
 152                     UART_ROUTING_IO1,
 153                     UART_ROUTING_UART3,
 154                     UART_ROUTING_UART4,
 155                     UART_ROUTING_UART1,
 156                     UART_ROUTING_IO6,
 157                     NULL,
 158                     },
 159 };
 160
 161 static struct aspeed_uart_routing_selector ast2500_uart1_sel = {
 162         .dev_attr = ROUTING_ATTR(UART_ROUTING_UART1),
 163         .reg = HICRA,
 164         .shift = 16,
 165         .mask = 0x7,
 166         .options = {
 167                     UART_ROUTING_IO1,
 168                     UART_ROUTING_IO2,
 169                     UART_ROUTING_IO3,
 170                     UART_ROUTING_IO4,
 171                     UART_ROUTING_UART2,
 172                     UART_ROUTING_UART3,
 173                     UART_ROUTING_UART4,
 174                     UART_ROUTING_IO6,
 175                     NULL,
 176                     },
 177 };
 178
 179 static struct aspeed_uart_routing_selector ast2500_io5_sel = {
 180         .dev_attr = ROUTING_ATTR(UART_ROUTING_IO5),
 181         .reg = HICRA,
 182         .shift = 12,
 183         .mask = 0x7,
 184         .options = {
 185                     UART_ROUTING_UART5,
 186                     UART_ROUTING_UART1,
 187                     UART_ROUTING_UART2,
 188                     UART_ROUTING_UART3,
 189                     UART_ROUTING_UART4,
 190                     UART_ROUTING_IO1,
 191                     UART_ROUTING_IO3,
 192                     UART_ROUTING_IO6,
 193                     NULL,
 194                     },
 195 };
 196
 197 static struct aspeed_uart_routing_selector ast2500_io4_sel = {
 198         .dev_attr = ROUTING_ATTR(UART_ROUTING_IO4),
 199         .reg = HICRA,
 200         .shift = 9,
 201         .mask = 0x7,
 202         .options = {
 203                     UART_ROUTING_UART4,
 204                     UART_ROUTING_UART5,
 205                     UART_ROUTING_UART1,
 206                     UART_ROUTING_UART2,
 207                     UART_ROUTING_UART3,
 208                     UART_ROUTING_IO1,
 209                     UART_ROUTING_IO2,
 210                     UART_ROUTING_IO6,
 211                     NULL,
 212                     },
 213 };
 214
 215 static struct aspeed_uart_routing_selector ast2500_io3_sel = {
 216         .dev_attr = ROUTING_ATTR(UART_ROUTING_IO3),
 217         .reg = HICRA,
 218         .shift = 6,
 219         .mask = 0x7,
 220         .options = {
 221                     UART_ROUTING_UART3,
 222                     UART_ROUTING_UART4,
 223                     UART_ROUTING_UART5,
 224                     UART_ROUTING_UART1,
 225                     UART_ROUTING_UART2,
 226                     UART_ROUTING_IO1,
 227                     UART_ROUTING_IO2,
 228                     UART_ROUTING_IO6,
 229                     NULL,
 230                     },
 231 };
 232
 233 static struct aspeed_uart_routing_selector ast2500_io2_sel = {
 234         .dev_attr = ROUTING_ATTR(UART_ROUTING_IO2),
 235         .reg = HICRA,
 236         .shift = 3,
 237         .mask = 0x7,
 238         .options = {
 239                     UART_ROUTING_UART2,
 240                     UART_ROUTING_UART3,
 241                     UART_ROUTING_UART4,
 242                     UART_ROUTING_UART5,
 243                     UART_ROUTING_UART1,
 244                     UART_ROUTING_IO3,
 245                     UART_ROUTING_IO4,
 246                     UART_ROUTING_IO6,
 247                     NULL,
 248                     },
 249 };
 250
 251 static struct aspeed_uart_routing_selector ast2500_io1_sel = {
 252         .dev_attr = ROUTING_ATTR(UART_ROUTING_IO1),
 253         .reg = HICRA,
 254         .shift = 0,
 255         .mask = 0x7,
 256         .options = {
 257                     UART_ROUTING_UART1,
 258                     UART_ROUTING_UART2,
 259                     UART_ROUTING_UART3,
 260                     UART_ROUTING_UART4,
 261                     UART_ROUTING_UART5,
 262                     UART_ROUTING_IO3,
 263                     UART_ROUTING_IO4,
 264                     UART_ROUTING_IO6,
 265                     NULL,
 266                     },
 267 };
 268
 269 static struct attribute *ast2500_uart_routing_attrs[] = {
 270         &ast2500_io6_sel.dev_attr.attr,
 271         &ast2500_uart5_sel.dev_attr.attr,
 272         &ast2500_uart4_sel.dev_attr.attr,
 273         &ast2500_uart3_sel.dev_attr.attr,
 274         &ast2500_uart2_sel.dev_attr.attr,
 275         &ast2500_uart1_sel.dev_attr.attr,
 276         &ast2500_io5_sel.dev_attr.attr,
 277         &ast2500_io4_sel.dev_attr.attr,
 278         &ast2500_io3_sel.dev_attr.attr,
 279         &ast2500_io2_sel.dev_attr.attr,
 280         &ast2500_io1_sel.dev_attr.attr,
 281         NULL,
 282 };
 283
 284 static const struct attribute_group ast2500_uart_routing_attr_group = {
 285         .attrs = ast2500_uart_routing_attrs,
 286 };
 287
 288 /* routing selector for AST26xx */
 289 static struct aspeed_uart_routing_selector ast2600_uart10_sel = {
 290         .dev_attr = ROUTING_ATTR(UART_ROUTING_UART10),
 291         .reg = HICR9,
 292         .shift = 12,
 293         .mask = 0xf,
 294         .options = {
 295                     UART_ROUTING_IO10,
 296                     UART_ROUTING_IO1,
 297                     UART_ROUTING_IO2,
 298                     UART_ROUTING_IO3,
 299                     UART_ROUTING_IO4,
 300                         UART_ROUTING_RES,
 301                     UART_ROUTING_UART1,
 302                     UART_ROUTING_UART2,
 303                     UART_ROUTING_UART3,
 304                     UART_ROUTING_UART4,
 305                     NULL,
 306                     },
 307 };
 308
 309 static struct aspeed_uart_routing_selector ast2600_io10_sel = {
 310         .dev_attr = ROUTING_ATTR(UART_ROUTING_IO10),
 311         .reg = HICR9,
 312         .shift = 8,
 313         .mask = 0xf,
 314         .options = {
 315                     UART_ROUTING_UART1,
 316                     UART_ROUTING_UART2,
 317                     UART_ROUTING_UART3,
 318                     UART_ROUTING_UART4,
 319                         UART_ROUTING_RES,
 320                     UART_ROUTING_IO1,
 321                     UART_ROUTING_IO2,
 322                     UART_ROUTING_IO3,
 323                     UART_ROUTING_IO4,
 324                         UART_ROUTING_RES,
 325                     UART_ROUTING_UART10,
 326                     NULL,
 327                     },
 328 };
 329
 330 static struct aspeed_uart_routing_selector ast2600_uart4_sel = {
 331         .dev_attr = ROUTING_ATTR(UART_ROUTING_UART4),
 332         .reg = HICRA,
 333         .shift = 25,
 334         .mask = 0x7,
 335         .options = {
 336                     UART_ROUTING_IO4,
 337                     UART_ROUTING_IO1,
 338                     UART_ROUTING_IO2,
 339                     UART_ROUTING_IO3,
 340                     UART_ROUTING_UART1,
 341                     UART_ROUTING_UART2,
 342                     UART_ROUTING_UART3,
 343                     UART_ROUTING_IO10,
 344                     NULL,
 345         },
 346 };
 347
 348 static struct aspeed_uart_routing_selector ast2600_uart3_sel = {
 349         .dev_attr = ROUTING_ATTR(UART_ROUTING_UART3),
 350         .reg = HICRA,
 351         .shift = 22,
 352         .mask = 0x7,
 353         .options = {
 354                     UART_ROUTING_IO3,
 355                     UART_ROUTING_IO4,
 356                     UART_ROUTING_IO1,
 357                     UART_ROUTING_IO2,
 358                     UART_ROUTING_UART4,
 359                     UART_ROUTING_UART1,
 360                     UART_ROUTING_UART2,
 361                     UART_ROUTING_IO10,
 362                     NULL,
 363                     },
 364 };
 365
 366 static struct aspeed_uart_routing_selector ast2600_uart2_sel = {
 367         .dev_attr = ROUTING_ATTR(UART_ROUTING_UART2),
 368         .reg = HICRA,
 369         .shift = 19,
 370         .mask = 0x7,
 371         .options = {
 372                     UART_ROUTING_IO2,
 373                     UART_ROUTING_IO3,
 374                     UART_ROUTING_IO4,
 375                     UART_ROUTING_IO1,
 376                     UART_ROUTING_UART3,
 377                     UART_ROUTING_UART4,
 378                     UART_ROUTING_UART1,
 379                     UART_ROUTING_IO10,
 380                     NULL,
 381                     },
 382 };
 383
 384 static struct aspeed_uart_routing_selector ast2600_uart1_sel = {
 385         .dev_attr = ROUTING_ATTR(UART_ROUTING_UART1),
 386         .reg = HICRA,
 387         .shift = 16,
 388         .mask = 0x7,
 389         .options = {
 390                     UART_ROUTING_IO1,
 391                     UART_ROUTING_IO2,
 392                     UART_ROUTING_IO3,
 393                     UART_ROUTING_IO4,
 394                     UART_ROUTING_UART2,
 395                     UART_ROUTING_UART3,
 396                     UART_ROUTING_UART4,
 397                     UART_ROUTING_IO10,
 398                     NULL,
 399                     },
 400 };
 401
 402 static struct aspeed_uart_routing_selector ast2600_io4_sel = {
 403         .dev_attr = ROUTING_ATTR(UART_ROUTING_IO4),
 404         .reg = HICRA,
 405         .shift = 9,
 406         .mask = 0x7,
 407         .options = {
 408                     UART_ROUTING_UART4,
 409                     UART_ROUTING_UART10,
 410                     UART_ROUTING_UART1,
 411                     UART_ROUTING_UART2,
 412                     UART_ROUTING_UART3,
 413                     UART_ROUTING_IO1,
 414                     UART_ROUTING_IO2,
 415                     UART_ROUTING_IO10,
 416                     NULL,
 417                     },
 418 };
 419
 420 static struct aspeed_uart_routing_selector ast2600_io3_sel = {
 421         .dev_attr = ROUTING_ATTR(UART_ROUTING_IO3),
 422         .reg = HICRA,
 423         .shift = 6,
 424         .mask = 0x7,
 425         .options = {
 426                     UART_ROUTING_UART3,
 427                     UART_ROUTING_UART4,
 428                     UART_ROUTING_UART10,
 429                     UART_ROUTING_UART1,
 430                     UART_ROUTING_UART2,
 431                     UART_ROUTING_IO1,
 432                     UART_ROUTING_IO2,
 433                     UART_ROUTING_IO10,
 434                     NULL,
 435                     },
 436 };
 437
 438 static struct aspeed_uart_routing_selector ast2600_io2_sel = {
 439         .dev_attr = ROUTING_ATTR(UART_ROUTING_IO2),
 440         .reg = HICRA,
 441         .shift = 3,
 442         .mask = 0x7,
 443         .options = {
 444                     UART_ROUTING_UART2,
 445                     UART_ROUTING_UART3,
 446                     UART_ROUTING_UART4,
 447                     UART_ROUTING_UART10,
 448                     UART_ROUTING_UART1,
 449                     UART_ROUTING_IO3,
 450                     UART_ROUTING_IO4,
 451                     UART_ROUTING_IO10,
 452                     NULL,
 453                     },
 454 };
 455
 456 static struct aspeed_uart_routing_selector ast2600_io1_sel = {
 457         .dev_attr = ROUTING_ATTR(UART_ROUTING_IO1),
 458         .reg = HICRA,
 459         .shift = 0,
 460         .mask = 0x7,
 461         .options = {
 462                     UART_ROUTING_UART1,
 463                     UART_ROUTING_UART2,
 464                     UART_ROUTING_UART3,
 465                     UART_ROUTING_UART4,
 466                     UART_ROUTING_UART10,
 467                     UART_ROUTING_IO3,
 468                     UART_ROUTING_IO4,
 469                     UART_ROUTING_IO10,
 470                     NULL,
 471                     },
 472 };
 473
 474 static struct attribute *ast2600_uart_routing_attrs[] = {
 475         &ast2600_uart10_sel.dev_attr.attr,
 476         &ast2600_io10_sel.dev_attr.attr,
 477         &ast2600_uart4_sel.dev_attr.attr,
 478         &ast2600_uart3_sel.dev_attr.attr,
 479         &ast2600_uart2_sel.dev_attr.attr,
 480         &ast2600_uart1_sel.dev_attr.attr,
 481         &ast2600_io4_sel.dev_attr.attr,
 482         &ast2600_io3_sel.dev_attr.attr,
 483         &ast2600_io2_sel.dev_attr.attr,
 484         &ast2600_io1_sel.dev_attr.attr,
 485         NULL,
 486 };
 487
 488 static const struct attribute_group ast2600_uart_routing_attr_group = {
 489         .attrs = ast2600_uart_routing_attrs,
 490 };
 491
 492 static ssize_t aspeed_uart_routing_show(struct device *dev,
 493                                         struct device_attribute *attr,
 494                                         char *buf)
 495 {
 496         struct aspeed_uart_routing *uart_routing = dev_get_drvdata(dev);
 497         struct aspeed_uart_routing_selector *sel = to_routing_selector(attr);
 498         int val, pos, len;
 499
 500         regmap_read(uart_routing->map, sel->reg, &val);
 501         val = (val >> sel->shift) & sel->mask;
 502
 503         len = 0;
 504         for (pos = 0; sel->options[pos] != NULL; ++pos) {
 505                 if (pos == val)
 506                         len += sysfs_emit_at(buf, len, "[%s] ", sel->options[pos]);
 507                 else
 508                         len += sysfs_emit_at(buf, len, "%s ", sel->options[pos]);
 509         }
 510
 511         if (val >= pos)
 512                 len += sysfs_emit_at(buf, len, "[unknown(%d)]", val);
 513
 514         len += sysfs_emit_at(buf, len, "\n");
 515
 516         return len;
 517 }
 518
 519 static ssize_t aspeed_uart_routing_store(struct device *dev,
 520                                          struct device_attribute *attr,
 521                                          const char *buf, size_t count)
 522 {
 523         struct aspeed_uart_routing *uart_routing = dev_get_drvdata(dev);
 524         struct aspeed_uart_routing_selector *sel = to_routing_selector(attr);
 525         int val;
 526
 527         val = match_string(sel->options, -1, buf);
 528         if (val < 0) {
 529                 dev_err(dev, "invalid value \"%s\"\n", buf);
 530                 return -EINVAL;
 531         }
 532
 533         regmap_update_bits(uart_routing->map, sel->reg,
 534                         (sel->mask << sel->shift),
 535                         (val & sel->mask) << sel->shift);
 536
 537         return count;
 538 }
 539
 540 static int aspeed_uart_routing_probe(struct platform_device *pdev)
 541 {
 542         int rc;
 543         struct device *dev = &pdev->dev;
 544         struct aspeed_uart_routing *uart_routing;
 545
 546         uart_routing = devm_kzalloc(&pdev->dev, sizeof(*uart_routing), GFP_KERNEL);
 547         if (!uart_routing)
 548                 return -ENOMEM;
 549
 550         uart_routing->map = syscon_node_to_regmap(dev->parent->of_node);
 551         if (IS_ERR(uart_routing->map)) {
 552                 dev_err(dev, "cannot get regmap\n");
 553                 return PTR_ERR(uart_routing->map);
 554         }
 555
 556         uart_routing->attr_grp = of_device_get_match_data(dev);
 557
 558         rc = sysfs_create_group(&dev->kobj, uart_routing->attr_grp);
 559         if (rc < 0)
 560                 return rc;
 561
 562         dev_set_drvdata(dev, uart_routing);
 563
 564         dev_info(dev, "module loaded\n");
 565
 566         return 0;
 567 }
 568
 569 static int aspeed_uart_routing_remove(struct platform_device *pdev)
 570 {
 571         struct device *dev = &pdev->dev;
 572         struct aspeed_uart_routing *uart_routing = platform_get_drvdata(pdev);
 573
 574         sysfs_remove_group(&dev->kobj, uart_routing->attr_grp);
 575
 576         return 0;
 577 }
 578
 579 static const struct of_device_id aspeed_uart_routing_table[] = {
 580         { .compatible = "aspeed,ast2400-uart-routing",
 581           .data = &ast2500_uart_routing_attr_group },
 582         { .compatible = "aspeed,ast2500-uart-routing",
 583           .data = &ast2500_uart_routing_attr_group },
 584         { .compatible = "aspeed,ast2600-uart-routing",
 585           .data = &ast2600_uart_routing_attr_group },
 586         { },
 587 };
 588
 589 static struct platform_driver aspeed_uart_routing_driver = {
 590         .driver = {
 591                 .name = "aspeed-uart-routing",
 592                 .of_match_table = aspeed_uart_routing_table,
 593         },
 594         .probe = aspeed_uart_routing_probe,
 595         .remove = aspeed_uart_routing_remove,
 596 };
 597
 598 module_platform_driver(aspeed_uart_routing_driver);
 599
 600 MODULE_AUTHOR("Oskar Senft <osk@google.com>");
 601 MODULE_AUTHOR("Chia-Wei Wang <chiawei_wang@aspeedtech.com>");
 602 MODULE_LICENSE("GPL v2");
 603 MODULE_DESCRIPTION("Driver to configure Aspeed UART routing");