1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Cadence USBSS DRD Driver. 4 * 5 * Copyright (C) 2018-2019 Cadence. 6 * Copyright (C) 2017-2018 NXP 7 * Copyright (C) 2019 Texas Instruments 8 * 9 * Author: Peter Chen <peter.chen@nxp.com> 10 * Pawel Laszczak <pawell@cadence.com> 11 * Roger Quadros <rogerq@ti.com> 12 */ 13 14 #include <linux/dma-mapping.h> 15 #include <linux/module.h> 16 #include <linux/kernel.h> 17 #include <linux/platform_device.h> 18 #include <linux/interrupt.h> 19 #include <linux/io.h> 20 #include <linux/pm_runtime.h> 21 22 #include "gadget.h" 23 #include "core.h" 24 #include "host-export.h" 25 #include "gadget-export.h" 26 #include "drd.h" 27 28 static int cdns3_idle_init(struct cdns3 *cdns); 29 30 static int cdns3_role_start(struct cdns3 *cdns, enum usb_role role) 31 { 32 int ret; 33 34 if (WARN_ON(role > USB_ROLE_DEVICE)) 35 return 0; 36 37 mutex_lock(&cdns->mutex); 38 cdns->role = role; 39 mutex_unlock(&cdns->mutex); 40 41 if (!cdns->roles[role]) 42 return -ENXIO; 43 44 if (cdns->roles[role]->state == CDNS3_ROLE_STATE_ACTIVE) 45 return 0; 46 47 mutex_lock(&cdns->mutex); 48 ret = cdns->roles[role]->start(cdns); 49 if (!ret) 50 cdns->roles[role]->state = CDNS3_ROLE_STATE_ACTIVE; 51 mutex_unlock(&cdns->mutex); 52 53 return ret; 54 } 55 56 static void cdns3_role_stop(struct cdns3 *cdns) 57 { 58 enum usb_role role = cdns->role; 59 60 if (WARN_ON(role > USB_ROLE_DEVICE)) 61 return; 62 63 if (cdns->roles[role]->state == CDNS3_ROLE_STATE_INACTIVE) 64 return; 65 66 mutex_lock(&cdns->mutex); 67 cdns->roles[role]->stop(cdns); 68 cdns->roles[role]->state = CDNS3_ROLE_STATE_INACTIVE; 69 mutex_unlock(&cdns->mutex); 70 } 71 72 static void cdns3_exit_roles(struct cdns3 *cdns) 73 { 74 cdns3_role_stop(cdns); 75 cdns3_drd_exit(cdns); 76 } 77 78 /** 79 * cdns3_core_init_role - initialize role of operation 80 * @cdns: Pointer to cdns3 structure 81 * 82 * Returns 0 on success otherwise negative errno 83 */ 84 static int cdns3_core_init_role(struct cdns3 *cdns) 85 { 86 struct device *dev = cdns->dev; 87 enum usb_dr_mode best_dr_mode; 88 enum usb_dr_mode dr_mode; 89 int ret; 90 91 dr_mode = usb_get_dr_mode(dev); 92 cdns->role = USB_ROLE_NONE; 93 94 /* 95 * If driver can't read mode by means of usb_get_dr_mode function then 96 * chooses mode according with Kernel configuration. This setting 97 * can be restricted later depending on strap pin configuration. 98 */ 99 if (dr_mode == USB_DR_MODE_UNKNOWN) { 100 if (IS_ENABLED(CONFIG_USB_CDNS3_HOST) && 101 IS_ENABLED(CONFIG_USB_CDNS3_GADGET)) 102 dr_mode = USB_DR_MODE_OTG; 103 else if (IS_ENABLED(CONFIG_USB_CDNS3_HOST)) 104 dr_mode = USB_DR_MODE_HOST; 105 else if (IS_ENABLED(CONFIG_USB_CDNS3_GADGET)) 106 dr_mode = USB_DR_MODE_PERIPHERAL; 107 } 108 109 /* 110 * At this point cdns->dr_mode contains strap configuration. 111 * Driver try update this setting considering kernel configuration 112 */ 113 best_dr_mode = cdns->dr_mode; 114 115 ret = cdns3_idle_init(cdns); 116 if (ret) 117 return ret; 118 119 if (dr_mode == USB_DR_MODE_OTG) { 120 best_dr_mode = cdns->dr_mode; 121 } else if (cdns->dr_mode == USB_DR_MODE_OTG) { 122 best_dr_mode = dr_mode; 123 } else if (cdns->dr_mode != dr_mode) { 124 dev_err(dev, "Incorrect DRD configuration\n"); 125 return -EINVAL; 126 } 127 128 dr_mode = best_dr_mode; 129 130 if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_HOST) { 131 ret = cdns3_host_init(cdns); 132 if (ret) { 133 dev_err(dev, "Host initialization failed with %d\n", 134 ret); 135 goto err; 136 } 137 } 138 139 if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_PERIPHERAL) { 140 ret = cdns3_gadget_init(cdns); 141 if (ret) { 142 dev_err(dev, "Device initialization failed with %d\n", 143 ret); 144 goto err; 145 } 146 } 147 148 cdns->dr_mode = dr_mode; 149 150 ret = cdns3_drd_update_mode(cdns); 151 if (ret) 152 goto err; 153 154 /* Initialize idle role to start with */ 155 ret = cdns3_role_start(cdns, USB_ROLE_NONE); 156 if (ret) 157 goto err; 158 159 switch (cdns->dr_mode) { 160 case USB_DR_MODE_OTG: 161 ret = cdns3_hw_role_switch(cdns); 162 if (ret) 163 goto err; 164 break; 165 case USB_DR_MODE_PERIPHERAL: 166 ret = cdns3_role_start(cdns, USB_ROLE_DEVICE); 167 if (ret) 168 goto err; 169 break; 170 case USB_DR_MODE_HOST: 171 ret = cdns3_role_start(cdns, USB_ROLE_HOST); 172 if (ret) 173 goto err; 174 break; 175 default: 176 ret = -EINVAL; 177 goto err; 178 } 179 180 return 0; 181 err: 182 cdns3_exit_roles(cdns); 183 return ret; 184 } 185 186 /** 187 * cdns3_hw_role_state_machine - role switch state machine based on hw events. 188 * @cdns: Pointer to controller structure. 189 * 190 * Returns next role to be entered based on hw events. 191 */ 192 static enum usb_role cdns3_hw_role_state_machine(struct cdns3 *cdns) 193 { 194 enum usb_role role = USB_ROLE_NONE; 195 int id, vbus; 196 197 if (cdns->dr_mode != USB_DR_MODE_OTG) { 198 if (cdns3_is_host(cdns)) 199 role = USB_ROLE_HOST; 200 if (cdns3_is_device(cdns)) 201 role = USB_ROLE_DEVICE; 202 203 return role; 204 } 205 206 id = cdns3_get_id(cdns); 207 vbus = cdns3_get_vbus(cdns); 208 209 /* 210 * Role change state machine 211 * Inputs: ID, VBUS 212 * Previous state: cdns->role 213 * Next state: role 214 */ 215 role = cdns->role; 216 217 switch (role) { 218 case USB_ROLE_NONE: 219 /* 220 * Driver treats USB_ROLE_NONE synonymous to IDLE state from 221 * controller specification. 222 */ 223 if (!id) 224 role = USB_ROLE_HOST; 225 else if (vbus) 226 role = USB_ROLE_DEVICE; 227 break; 228 case USB_ROLE_HOST: /* from HOST, we can only change to NONE */ 229 if (id) 230 role = USB_ROLE_NONE; 231 break; 232 case USB_ROLE_DEVICE: /* from GADGET, we can only change to NONE*/ 233 if (!vbus) 234 role = USB_ROLE_NONE; 235 break; 236 } 237 238 dev_dbg(cdns->dev, "role %d -> %d\n", cdns->role, role); 239 240 return role; 241 } 242 243 static int cdns3_idle_role_start(struct cdns3 *cdns) 244 { 245 return 0; 246 } 247 248 static void cdns3_idle_role_stop(struct cdns3 *cdns) 249 { 250 /* Program Lane swap and bring PHY out of RESET */ 251 phy_reset(cdns->usb3_phy); 252 } 253 254 static int cdns3_idle_init(struct cdns3 *cdns) 255 { 256 struct cdns3_role_driver *rdrv; 257 258 rdrv = devm_kzalloc(cdns->dev, sizeof(*rdrv), GFP_KERNEL); 259 if (!rdrv) 260 return -ENOMEM; 261 262 rdrv->start = cdns3_idle_role_start; 263 rdrv->stop = cdns3_idle_role_stop; 264 rdrv->state = CDNS3_ROLE_STATE_INACTIVE; 265 rdrv->suspend = NULL; 266 rdrv->resume = NULL; 267 rdrv->name = "idle"; 268 269 cdns->roles[USB_ROLE_NONE] = rdrv; 270 271 return 0; 272 } 273 274 /** 275 * cdns3_hw_role_switch - switch roles based on HW state 276 * @cdns: controller 277 */ 278 int cdns3_hw_role_switch(struct cdns3 *cdns) 279 { 280 enum usb_role real_role, current_role; 281 int ret = 0; 282 283 pm_runtime_get_sync(cdns->dev); 284 285 current_role = cdns->role; 286 real_role = cdns3_hw_role_state_machine(cdns); 287 288 /* Do nothing if nothing changed */ 289 if (current_role == real_role) 290 goto exit; 291 292 cdns3_role_stop(cdns); 293 294 dev_dbg(cdns->dev, "Switching role %d -> %d", current_role, real_role); 295 296 ret = cdns3_role_start(cdns, real_role); 297 if (ret) { 298 /* Back to current role */ 299 dev_err(cdns->dev, "set %d has failed, back to %d\n", 300 real_role, current_role); 301 ret = cdns3_role_start(cdns, current_role); 302 if (ret) 303 dev_err(cdns->dev, "back to %d failed too\n", 304 current_role); 305 } 306 exit: 307 pm_runtime_put_sync(cdns->dev); 308 return ret; 309 } 310 311 /** 312 * cdsn3_role_get - get current role of controller. 313 * 314 * @sw: pointer to USB role switch structure 315 * 316 * Returns role 317 */ 318 static enum usb_role cdns3_role_get(struct usb_role_switch *sw) 319 { 320 struct cdns3 *cdns = usb_role_switch_get_drvdata(sw); 321 322 return cdns->role; 323 } 324 325 /** 326 * cdns3_role_set - set current role of controller. 327 * 328 * @sw: pointer to USB role switch structure 329 * @role: the previous role 330 * Handles below events: 331 * - Role switch for dual-role devices 332 * - USB_ROLE_GADGET <--> USB_ROLE_NONE for peripheral-only devices 333 */ 334 static int cdns3_role_set(struct usb_role_switch *sw, enum usb_role role) 335 { 336 struct cdns3 *cdns = usb_role_switch_get_drvdata(sw); 337 int ret = 0; 338 339 pm_runtime_get_sync(cdns->dev); 340 341 if (cdns->role == role) 342 goto pm_put; 343 344 if (cdns->dr_mode == USB_DR_MODE_HOST) { 345 switch (role) { 346 case USB_ROLE_NONE: 347 case USB_ROLE_HOST: 348 break; 349 default: 350 goto pm_put; 351 } 352 } 353 354 if (cdns->dr_mode == USB_DR_MODE_PERIPHERAL) { 355 switch (role) { 356 case USB_ROLE_NONE: 357 case USB_ROLE_DEVICE: 358 break; 359 default: 360 goto pm_put; 361 } 362 } 363 364 cdns3_role_stop(cdns); 365 ret = cdns3_role_start(cdns, role); 366 if (ret) 367 dev_err(cdns->dev, "set role %d has failed\n", role); 368 369 pm_put: 370 pm_runtime_put_sync(cdns->dev); 371 return ret; 372 } 373 374 /** 375 * cdns3_probe - probe for cdns3 core device 376 * @pdev: Pointer to cdns3 core platform device 377 * 378 * Returns 0 on success otherwise negative errno 379 */ 380 static int cdns3_probe(struct platform_device *pdev) 381 { 382 struct usb_role_switch_desc sw_desc = { }; 383 struct device *dev = &pdev->dev; 384 struct resource *res; 385 struct cdns3 *cdns; 386 void __iomem *regs; 387 int ret; 388 389 ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32)); 390 if (ret) { 391 dev_err(dev, "error setting dma mask: %d\n", ret); 392 return ret; 393 } 394 395 cdns = devm_kzalloc(dev, sizeof(*cdns), GFP_KERNEL); 396 if (!cdns) 397 return -ENOMEM; 398 399 cdns->dev = dev; 400 401 platform_set_drvdata(pdev, cdns); 402 403 res = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "host"); 404 if (!res) { 405 dev_err(dev, "missing host IRQ\n"); 406 return -ENODEV; 407 } 408 409 cdns->xhci_res[0] = *res; 410 411 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "xhci"); 412 if (!res) { 413 dev_err(dev, "couldn't get xhci resource\n"); 414 return -ENXIO; 415 } 416 417 cdns->xhci_res[1] = *res; 418 419 cdns->dev_irq = platform_get_irq_byname(pdev, "peripheral"); 420 if (cdns->dev_irq == -EPROBE_DEFER) 421 return cdns->dev_irq; 422 423 if (cdns->dev_irq < 0) 424 dev_err(dev, "couldn't get peripheral irq\n"); 425 426 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dev"); 427 regs = devm_ioremap_resource(dev, res); 428 if (IS_ERR(regs)) 429 return PTR_ERR(regs); 430 cdns->dev_regs = regs; 431 432 cdns->otg_irq = platform_get_irq_byname(pdev, "otg"); 433 if (cdns->otg_irq == -EPROBE_DEFER) 434 return cdns->otg_irq; 435 436 if (cdns->otg_irq < 0) { 437 dev_err(dev, "couldn't get otg irq\n"); 438 return cdns->otg_irq; 439 } 440 441 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "otg"); 442 if (!res) { 443 dev_err(dev, "couldn't get otg resource\n"); 444 return -ENXIO; 445 } 446 447 cdns->otg_res = *res; 448 449 mutex_init(&cdns->mutex); 450 451 cdns->usb2_phy = devm_phy_optional_get(dev, "cdns3,usb2-phy"); 452 if (IS_ERR(cdns->usb2_phy)) 453 return PTR_ERR(cdns->usb2_phy); 454 455 ret = phy_init(cdns->usb2_phy); 456 if (ret) 457 return ret; 458 459 cdns->usb3_phy = devm_phy_optional_get(dev, "cdns3,usb3-phy"); 460 if (IS_ERR(cdns->usb3_phy)) 461 return PTR_ERR(cdns->usb3_phy); 462 463 ret = phy_init(cdns->usb3_phy); 464 if (ret) 465 goto err1; 466 467 ret = phy_power_on(cdns->usb2_phy); 468 if (ret) 469 goto err2; 470 471 ret = phy_power_on(cdns->usb3_phy); 472 if (ret) 473 goto err3; 474 475 sw_desc.set = cdns3_role_set; 476 sw_desc.get = cdns3_role_get; 477 sw_desc.allow_userspace_control = true; 478 sw_desc.driver_data = cdns; 479 if (device_property_read_bool(dev, "usb-role-switch")) 480 sw_desc.fwnode = dev->fwnode; 481 482 cdns->role_sw = usb_role_switch_register(dev, &sw_desc); 483 if (IS_ERR(cdns->role_sw)) { 484 ret = PTR_ERR(cdns->role_sw); 485 dev_warn(dev, "Unable to register Role Switch\n"); 486 goto err4; 487 } 488 489 ret = cdns3_drd_init(cdns); 490 if (ret) 491 goto err5; 492 493 ret = cdns3_core_init_role(cdns); 494 if (ret) 495 goto err5; 496 497 device_set_wakeup_capable(dev, true); 498 pm_runtime_set_active(dev); 499 pm_runtime_enable(dev); 500 501 /* 502 * The controller needs less time between bus and controller suspend, 503 * and we also needs a small delay to avoid frequently entering low 504 * power mode. 505 */ 506 pm_runtime_set_autosuspend_delay(dev, 20); 507 pm_runtime_mark_last_busy(dev); 508 pm_runtime_use_autosuspend(dev); 509 dev_dbg(dev, "Cadence USB3 core: probe succeed\n"); 510 511 return 0; 512 err5: 513 cdns3_drd_exit(cdns); 514 usb_role_switch_unregister(cdns->role_sw); 515 err4: 516 phy_power_off(cdns->usb3_phy); 517 518 err3: 519 phy_power_off(cdns->usb2_phy); 520 err2: 521 phy_exit(cdns->usb3_phy); 522 err1: 523 phy_exit(cdns->usb2_phy); 524 525 return ret; 526 } 527 528 /** 529 * cdns3_remove - unbind drd driver and clean up 530 * @pdev: Pointer to Linux platform device 531 * 532 * Returns 0 on success otherwise negative errno 533 */ 534 static int cdns3_remove(struct platform_device *pdev) 535 { 536 struct cdns3 *cdns = platform_get_drvdata(pdev); 537 538 pm_runtime_get_sync(&pdev->dev); 539 pm_runtime_disable(&pdev->dev); 540 pm_runtime_put_noidle(&pdev->dev); 541 cdns3_exit_roles(cdns); 542 usb_role_switch_unregister(cdns->role_sw); 543 phy_power_off(cdns->usb2_phy); 544 phy_power_off(cdns->usb3_phy); 545 phy_exit(cdns->usb2_phy); 546 phy_exit(cdns->usb3_phy); 547 return 0; 548 } 549 550 #ifdef CONFIG_PM_SLEEP 551 552 static int cdns3_suspend(struct device *dev) 553 { 554 struct cdns3 *cdns = dev_get_drvdata(dev); 555 unsigned long flags; 556 557 if (cdns->role == USB_ROLE_HOST) 558 return 0; 559 560 if (pm_runtime_status_suspended(dev)) 561 pm_runtime_resume(dev); 562 563 if (cdns->roles[cdns->role]->suspend) { 564 spin_lock_irqsave(&cdns->gadget_dev->lock, flags); 565 cdns->roles[cdns->role]->suspend(cdns, false); 566 spin_unlock_irqrestore(&cdns->gadget_dev->lock, flags); 567 } 568 569 return 0; 570 } 571 572 static int cdns3_resume(struct device *dev) 573 { 574 struct cdns3 *cdns = dev_get_drvdata(dev); 575 unsigned long flags; 576 577 if (cdns->role == USB_ROLE_HOST) 578 return 0; 579 580 if (cdns->roles[cdns->role]->resume) { 581 spin_lock_irqsave(&cdns->gadget_dev->lock, flags); 582 cdns->roles[cdns->role]->resume(cdns, false); 583 spin_unlock_irqrestore(&cdns->gadget_dev->lock, flags); 584 } 585 586 pm_runtime_disable(dev); 587 pm_runtime_set_active(dev); 588 pm_runtime_enable(dev); 589 590 return 0; 591 } 592 #endif 593 594 static const struct dev_pm_ops cdns3_pm_ops = { 595 SET_SYSTEM_SLEEP_PM_OPS(cdns3_suspend, cdns3_resume) 596 }; 597 598 #ifdef CONFIG_OF 599 static const struct of_device_id of_cdns3_match[] = { 600 { .compatible = "cdns,usb3" }, 601 { }, 602 }; 603 MODULE_DEVICE_TABLE(of, of_cdns3_match); 604 #endif 605 606 static struct platform_driver cdns3_driver = { 607 .probe = cdns3_probe, 608 .remove = cdns3_remove, 609 .driver = { 610 .name = "cdns-usb3", 611 .of_match_table = of_match_ptr(of_cdns3_match), 612 .pm = &cdns3_pm_ops, 613 }, 614 }; 615 616 module_platform_driver(cdns3_driver); 617 618 MODULE_ALIAS("platform:cdns3"); 619 MODULE_AUTHOR("Pawel Laszczak <pawell@cadence.com>"); 620 MODULE_LICENSE("GPL v2"); 621 MODULE_DESCRIPTION("Cadence USB3 DRD Controller Driver"); 622