aspeed-uart-routing.c (14361B)
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 35struct aspeed_uart_routing { 36 struct regmap *map; 37 struct attribute_group const *attr_grp; 38}; 39 40struct 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 51static ssize_t aspeed_uart_routing_show(struct device *dev, 52 struct device_attribute *attr, 53 char *buf); 54 55static 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 */ 67static 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 87static 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 107static 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 125static 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 143static 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 161static 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 179static 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 197static 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 215static 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 233static 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 251static 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 269static 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 284static const struct attribute_group ast2500_uart_routing_attr_group = { 285 .attrs = ast2500_uart_routing_attrs, 286}; 287 288/* routing selector for AST26xx */ 289static 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 309static 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 330static 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 348static 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 366static 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 384static 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 402static 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 420static 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 438static 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 456static 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 474static 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 488static const struct attribute_group ast2600_uart_routing_attr_group = { 489 .attrs = ast2600_uart_routing_attrs, 490}; 491 492static 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 519static 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 540static 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 569static 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 579static 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 589static 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 598module_platform_driver(aspeed_uart_routing_driver); 599 600MODULE_AUTHOR("Oskar Senft <osk@google.com>"); 601MODULE_AUTHOR("Chia-Wei Wang <chiawei_wang@aspeedtech.com>"); 602MODULE_LICENSE("GPL v2"); 603MODULE_DESCRIPTION("Driver to configure Aspeed UART routing");