drivers/usb/cdns3/core.c

   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 <[email protected]>
  10  *         Pawel Laszczak <[email protected]>
  11  *         Roger Quadros <[email protected]>
  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 inline
  31 struct cdns3_role_driver *cdns3_get_current_role_driver(struct cdns3 *cdns)
  32 {
  33         WARN_ON(!cdns->roles[cdns->role]);
  34         return cdns->roles[cdns->role];
  35 }
  36
  37 static int cdns3_role_start(struct cdns3 *cdns, enum usb_role role)
  38 {
  39         int ret;
  40
  41         if (WARN_ON(role > USB_ROLE_DEVICE))
  42                 return 0;
  43
  44         mutex_lock(&cdns->mutex);
  45         cdns->role = role;
  46         mutex_unlock(&cdns->mutex);
  47
  48         if (!cdns->roles[role])
  49                 return -ENXIO;
  50
  51         if (cdns->roles[role]->state == CDNS3_ROLE_STATE_ACTIVE)
  52                 return 0;
  53
  54         mutex_lock(&cdns->mutex);
  55         ret = cdns->roles[role]->start(cdns);
  56         if (!ret)
  57                 cdns->roles[role]->state = CDNS3_ROLE_STATE_ACTIVE;
  58         mutex_unlock(&cdns->mutex);
  59
  60         return ret;
  61 }
  62
  63 static void cdns3_role_stop(struct cdns3 *cdns)
  64 {
  65         enum usb_role role = cdns->role;
  66
  67         if (WARN_ON(role > USB_ROLE_DEVICE))
  68                 return;
  69
  70         if (cdns->roles[role]->state == CDNS3_ROLE_STATE_INACTIVE)
  71                 return;
  72
  73         mutex_lock(&cdns->mutex);
  74         cdns->roles[role]->stop(cdns);
  75         cdns->roles[role]->state = CDNS3_ROLE_STATE_INACTIVE;
  76         mutex_unlock(&cdns->mutex);
  77 }
  78
  79 static void cdns3_exit_roles(struct cdns3 *cdns)
  80 {
  81         cdns3_role_stop(cdns);
  82         cdns3_drd_exit(cdns);
  83 }
  84
  85 /**
  86  * cdns3_core_init_role - initialize role of operation
  87  * @cdns: Pointer to cdns3 structure
  88  *
  89  * Returns 0 on success otherwise negative errno
  90  */
  91 static int cdns3_core_init_role(struct cdns3 *cdns)
  92 {
  93         struct device *dev = cdns->dev;
  94         enum usb_dr_mode best_dr_mode;
  95         enum usb_dr_mode dr_mode;
  96         int ret = 0;
  97
  98         dr_mode = usb_get_dr_mode(dev);
  99         cdns->role = USB_ROLE_NONE;
 100
 101         /*
 102          * If driver can't read mode by means of usb_get_dr_mode function then
 103          * chooses mode according with Kernel configuration. This setting
 104          * can be restricted later depending on strap pin configuration.
 105          */
 106         if (dr_mode == USB_DR_MODE_UNKNOWN) {
 107                 if (IS_ENABLED(CONFIG_USB_CDNS3_HOST) &&
 108                     IS_ENABLED(CONFIG_USB_CDNS3_GADGET))
 109                         dr_mode = USB_DR_MODE_OTG;
 110                 else if (IS_ENABLED(CONFIG_USB_CDNS3_HOST))
 111                         dr_mode = USB_DR_MODE_HOST;
 112                 else if (IS_ENABLED(CONFIG_USB_CDNS3_GADGET))
 113                         dr_mode = USB_DR_MODE_PERIPHERAL;
 114         }
 115
 116         /*
 117          * At this point cdns->dr_mode contains strap configuration.
 118          * Driver try update this setting considering kernel configuration
 119          */
 120         best_dr_mode = cdns->dr_mode;
 121
 122         ret = cdns3_idle_init(cdns);
 123         if (ret)
 124                 return ret;
 125
 126         if (dr_mode == USB_DR_MODE_OTG) {
 127                 best_dr_mode = cdns->dr_mode;
 128         } else if (cdns->dr_mode == USB_DR_MODE_OTG) {
 129                 best_dr_mode = dr_mode;
 130         } else if (cdns->dr_mode != dr_mode) {
 131                 dev_err(dev, "Incorrect DRD configuration\n");
 132                 return -EINVAL;
 133         }
 134
 135         dr_mode = best_dr_mode;
 136
 137         if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_HOST) {
 138                 ret = cdns3_host_init(cdns);
 139                 if (ret) {
 140                         dev_err(dev, "Host initialization failed with %d\n",
 141                                 ret);
 142                         goto err;
 143                 }
 144         }
 145
 146         if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_PERIPHERAL) {
 147                 ret = cdns3_gadget_init(cdns);
 148                 if (ret) {
 149                         dev_err(dev, "Device initialization failed with %d\n",
 150                                 ret);
 151                         goto err;
 152                 }
 153         }
 154
 155         cdns->dr_mode = dr_mode;
 156
 157         ret = cdns3_drd_update_mode(cdns);
 158         if (ret)
 159                 goto err;
 160
 161         /* Initialize idle role to start with */
 162         ret = cdns3_role_start(cdns, USB_ROLE_NONE);
 163         if (ret)
 164                 goto err;
 165
 166         switch (cdns->dr_mode) {
 167         case USB_DR_MODE_OTG:
 168                 ret = cdns3_hw_role_switch(cdns);
 169                 if (ret)
 170                         goto err;
 171                 break;
 172         case USB_DR_MODE_PERIPHERAL:
 173                 ret = cdns3_role_start(cdns, USB_ROLE_DEVICE);
 174                 if (ret)
 175                         goto err;
 176                 break;
 177         case USB_DR_MODE_HOST:
 178                 ret = cdns3_role_start(cdns, USB_ROLE_HOST);
 179                 if (ret)
 180                         goto err;
 181                 break;
 182         default:
 183                 ret = -EINVAL;
 184                 goto err;
 185         }
 186
 187         return ret;
 188 err:
 189         cdns3_exit_roles(cdns);
 190         return ret;
 191 }
 192
 193 /**
 194  * cdns3_hw_role_state_machine  - role switch state machine based on hw events.
 195  * @cdns: Pointer to controller structure.
 196  *
 197  * Returns next role to be entered based on hw events.
 198  */
 199 static enum usb_role cdns3_hw_role_state_machine(struct cdns3 *cdns)
 200 {
 201         enum usb_role role;
 202         int id, vbus;
 203
 204         if (cdns->dr_mode != USB_DR_MODE_OTG)
 205                 goto not_otg;
 206
 207         id = cdns3_get_id(cdns);
 208         vbus = cdns3_get_vbus(cdns);
 209
 210         /*
 211          * Role change state machine
 212          * Inputs: ID, VBUS
 213          * Previous state: cdns->role
 214          * Next state: role
 215          */
 216         role = cdns->role;
 217
 218         switch (role) {
 219         case USB_ROLE_NONE:
 220                 /*
 221                  * Driver treats USB_ROLE_NONE synonymous to IDLE state from
 222                  * controller specification.
 223                  */
 224                 if (!id)
 225                         role = USB_ROLE_HOST;
 226                 else if (vbus)
 227                         role = USB_ROLE_DEVICE;
 228                 break;
 229         case USB_ROLE_HOST: /* from HOST, we can only change to NONE */
 230                 if (id)
 231                         role = USB_ROLE_NONE;
 232                 break;
 233         case USB_ROLE_DEVICE: /* from GADGET, we can only change to NONE*/
 234                 if (!vbus)
 235                         role = USB_ROLE_NONE;
 236                 break;
 237         }
 238
 239         dev_dbg(cdns->dev, "role %d -> %d\n", cdns->role, role);
 240
 241         return role;
 242
 243 not_otg:
 244         if (cdns3_is_host(cdns))
 245                 role = USB_ROLE_HOST;
 246         if (cdns3_is_device(cdns))
 247                 role = USB_ROLE_DEVICE;
 248
 249         return role;
 250 }
 251
 252 static int cdns3_idle_role_start(struct cdns3 *cdns)
 253 {
 254         return 0;
 255 }
 256
 257 static void cdns3_idle_role_stop(struct cdns3 *cdns)
 258 {
 259         /* Program Lane swap and bring PHY out of RESET */
 260         phy_reset(cdns->usb3_phy);
 261 }
 262
 263 static int cdns3_idle_init(struct cdns3 *cdns)
 264 {
 265         struct cdns3_role_driver *rdrv;
 266
 267         rdrv = devm_kzalloc(cdns->dev, sizeof(*rdrv), GFP_KERNEL);
 268         if (!rdrv)
 269                 return -ENOMEM;
 270
 271         rdrv->start = cdns3_idle_role_start;
 272         rdrv->stop = cdns3_idle_role_stop;
 273         rdrv->state = CDNS3_ROLE_STATE_INACTIVE;
 274         rdrv->suspend = NULL;
 275         rdrv->resume = NULL;
 276         rdrv->name = "idle";
 277
 278         cdns->roles[USB_ROLE_NONE] = rdrv;
 279
 280         return 0;
 281 }
 282
 283 /**
 284  * cdns3_hw_role_switch - switch roles based on HW state
 285  * @cdns3: controller
 286  */
 287 int cdns3_hw_role_switch(struct cdns3 *cdns)
 288 {
 289         enum usb_role real_role, current_role;
 290         int ret = 0;
 291
 292         pm_runtime_get_sync(cdns->dev);
 293
 294         current_role = cdns->role;
 295         real_role = cdns3_hw_role_state_machine(cdns);
 296
 297         /* Do nothing if nothing changed */
 298         if (current_role == real_role)
 299                 goto exit;
 300
 301         cdns3_role_stop(cdns);
 302
 303         dev_dbg(cdns->dev, "Switching role %d -> %d", current_role, real_role);
 304
 305         ret = cdns3_role_start(cdns, real_role);
 306         if (ret) {
 307                 /* Back to current role */
 308                 dev_err(cdns->dev, "set %d has failed, back to %d\n",
 309                         real_role, current_role);
 310                 ret = cdns3_role_start(cdns, current_role);
 311                 if (ret)
 312                         dev_err(cdns->dev, "back to %d failed too\n",
 313                                 current_role);
 314         }
 315 exit:
 316         pm_runtime_put_sync(cdns->dev);
 317         return ret;
 318 }
 319
 320 /**
 321  * cdsn3_role_get - get current role of controller.
 322  *
 323  * @dev: Pointer to device structure
 324  *
 325  * Returns role
 326  */
 327 static enum usb_role cdns3_role_get(struct usb_role_switch *sw)
 328 {
 329         struct cdns3 *cdns = usb_role_switch_get_drvdata(sw);
 330
 331         return cdns->role;
 332 }
 333
 334 /**
 335  * cdns3_role_set - set current role of controller.
 336  *
 337  * @dev: pointer to device object
 338  * @role - the previous role
 339  * Handles below events:
 340  * - Role switch for dual-role devices
 341  * - USB_ROLE_GADGET <--> USB_ROLE_NONE for peripheral-only devices
 342  */
 343 static int cdns3_role_set(struct usb_role_switch *sw, enum usb_role role)
 344 {
 345         struct cdns3 *cdns = usb_role_switch_get_drvdata(sw);
 346         int ret = 0;
 347
 348         pm_runtime_get_sync(cdns->dev);
 349
 350         if (cdns->role == role)
 351                 goto pm_put;
 352
 353         if (cdns->dr_mode == USB_DR_MODE_HOST) {
 354                 switch (role) {
 355                 case USB_ROLE_NONE:
 356                 case USB_ROLE_HOST:
 357                         break;
 358                 default:
 359                         ret = -EPERM;
 360                         goto pm_put;
 361                 }
 362         }
 363
 364         if (cdns->dr_mode == USB_DR_MODE_PERIPHERAL) {
 365                 switch (role) {
 366                 case USB_ROLE_NONE:
 367                 case USB_ROLE_DEVICE:
 368                         break;
 369                 default:
 370                         ret = -EPERM;
 371                         goto pm_put;
 372                 }
 373         }
 374
 375         cdns3_role_stop(cdns);
 376         ret = cdns3_role_start(cdns, role);
 377         if (ret) {
 378                 dev_err(cdns->dev, "set role %d has failed\n", role);
 379                 ret = -EPERM;
 380         }
 381
 382 pm_put:
 383         pm_runtime_put_sync(cdns->dev);
 384         return ret;
 385 }
 386
 387 /**
 388  * cdns3_probe - probe for cdns3 core device
 389  * @pdev: Pointer to cdns3 core platform device
 390  *
 391  * Returns 0 on success otherwise negative errno
 392  */
 393 static int cdns3_probe(struct platform_device *pdev)
 394 {
 395         struct usb_role_switch_desc sw_desc = { };
 396         struct device *dev = &pdev->dev;
 397         struct resource *res;
 398         struct cdns3 *cdns;
 399         void __iomem *regs;
 400         int ret;
 401
 402         ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
 403         if (ret) {
 404                 dev_err(dev, "error setting dma mask: %d\n", ret);
 405                 return -ENODEV;
 406         }
 407
 408         cdns = devm_kzalloc(dev, sizeof(*cdns), GFP_KERNEL);
 409         if (!cdns)
 410                 return -ENOMEM;
 411
 412         cdns->dev = dev;
 413
 414         platform_set_drvdata(pdev, cdns);
 415
 416         res = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "host");
 417         if (!res) {
 418                 dev_err(dev, "missing host IRQ\n");
 419                 return -ENODEV;
 420         }
 421
 422         cdns->xhci_res[0] = *res;
 423
 424         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "xhci");
 425         if (!res) {
 426                 dev_err(dev, "couldn't get xhci resource\n");
 427                 return -ENXIO;
 428         }
 429
 430         cdns->xhci_res[1] = *res;
 431
 432         cdns->dev_irq = platform_get_irq_byname(pdev, "peripheral");
 433         if (cdns->dev_irq == -EPROBE_DEFER)
 434                 return cdns->dev_irq;
 435
 436         if (cdns->dev_irq < 0)
 437                 dev_err(dev, "couldn't get peripheral irq\n");
 438
 439         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dev");
 440         regs = devm_ioremap_resource(dev, res);
 441         if (IS_ERR(regs))
 442                 return PTR_ERR(regs);
 443         cdns->dev_regs  = regs;
 444
 445         cdns->otg_irq = platform_get_irq_byname(pdev, "otg");
 446         if (cdns->otg_irq == -EPROBE_DEFER)
 447                 return cdns->otg_irq;
 448
 449         if (cdns->otg_irq < 0) {
 450                 dev_err(dev, "couldn't get otg irq\n");
 451                 return cdns->otg_irq;
 452         }
 453
 454         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "otg");
 455         if (!res) {
 456                 dev_err(dev, "couldn't get otg resource\n");
 457                 return -ENXIO;
 458         }
 459
 460         cdns->otg_res = *res;
 461
 462         mutex_init(&cdns->mutex);
 463
 464         cdns->usb2_phy = devm_phy_optional_get(dev, "cdns3,usb2-phy");
 465         if (IS_ERR(cdns->usb2_phy))
 466                 return PTR_ERR(cdns->usb2_phy);
 467
 468         ret = phy_init(cdns->usb2_phy);
 469         if (ret)
 470                 return ret;
 471
 472         cdns->usb3_phy = devm_phy_optional_get(dev, "cdns3,usb3-phy");
 473         if (IS_ERR(cdns->usb3_phy))
 474                 return PTR_ERR(cdns->usb3_phy);
 475
 476         ret = phy_init(cdns->usb3_phy);
 477         if (ret)
 478                 goto err1;
 479
 480         ret = phy_power_on(cdns->usb2_phy);
 481         if (ret)
 482                 goto err2;
 483
 484         ret = phy_power_on(cdns->usb3_phy);
 485         if (ret)
 486                 goto err3;
 487
 488         sw_desc.set = cdns3_role_set;
 489         sw_desc.get = cdns3_role_get;
 490         sw_desc.allow_userspace_control = true;
 491         sw_desc.driver_data = cdns;
 492         if (device_property_read_bool(dev, "usb-role-switch"))
 493                 sw_desc.fwnode = dev->fwnode;
 494
 495         cdns->role_sw = usb_role_switch_register(dev, &sw_desc);
 496         if (IS_ERR(cdns->role_sw)) {
 497                 ret = PTR_ERR(cdns->role_sw);
 498                 dev_warn(dev, "Unable to register Role Switch\n");
 499                 goto err4;
 500         }
 501
 502         ret = cdns3_drd_init(cdns);
 503         if (ret)
 504                 goto err5;
 505
 506         ret = cdns3_core_init_role(cdns);
 507         if (ret)
 508                 goto err5;
 509
 510         device_set_wakeup_capable(dev, true);
 511         pm_runtime_set_active(dev);
 512         pm_runtime_enable(dev);
 513
 514         /*
 515          * The controller needs less time between bus and controller suspend,
 516          * and we also needs a small delay to avoid frequently entering low
 517          * power mode.
 518          */
 519         pm_runtime_set_autosuspend_delay(dev, 20);
 520         pm_runtime_mark_last_busy(dev);
 521         pm_runtime_use_autosuspend(dev);
 522         dev_dbg(dev, "Cadence USB3 core: probe succeed\n");
 523
 524         return 0;
 525 err5:
 526         cdns3_drd_exit(cdns);
 527         usb_role_switch_unregister(cdns->role_sw);
 528 err4:
 529         phy_power_off(cdns->usb3_phy);
 530
 531 err3:
 532         phy_power_off(cdns->usb2_phy);
 533 err2:
 534         phy_exit(cdns->usb3_phy);
 535 err1:
 536         phy_exit(cdns->usb2_phy);
 537
 538         return ret;
 539 }
 540
 541 /**
 542  * cdns3_remove - unbind drd driver and clean up
 543  * @pdev: Pointer to Linux platform device
 544  *
 545  * Returns 0 on success otherwise negative errno
 546  */
 547 static int cdns3_remove(struct platform_device *pdev)
 548 {
 549         struct cdns3 *cdns = platform_get_drvdata(pdev);
 550
 551         pm_runtime_get_sync(&pdev->dev);
 552         pm_runtime_disable(&pdev->dev);
 553         pm_runtime_put_noidle(&pdev->dev);
 554         cdns3_exit_roles(cdns);
 555         usb_role_switch_unregister(cdns->role_sw);
 556         phy_power_off(cdns->usb2_phy);
 557         phy_power_off(cdns->usb3_phy);
 558         phy_exit(cdns->usb2_phy);
 559         phy_exit(cdns->usb3_phy);
 560         return 0;
 561 }
 562
 563 #ifdef CONFIG_PM_SLEEP
 564
 565 static int cdns3_suspend(struct device *dev)
 566 {
 567         struct cdns3 *cdns = dev_get_drvdata(dev);
 568         unsigned long flags;
 569
 570         if (cdns->role == USB_ROLE_HOST)
 571                 return 0;
 572
 573         if (pm_runtime_status_suspended(dev))
 574                 pm_runtime_resume(dev);
 575
 576         if (cdns->roles[cdns->role]->suspend) {
 577                 spin_lock_irqsave(&cdns->gadget_dev->lock, flags);
 578                 cdns->roles[cdns->role]->suspend(cdns, false);
 579                 spin_unlock_irqrestore(&cdns->gadget_dev->lock, flags);
 580         }
 581
 582         return 0;
 583 }
 584
 585 static int cdns3_resume(struct device *dev)
 586 {
 587         struct cdns3 *cdns = dev_get_drvdata(dev);
 588         unsigned long flags;
 589
 590         if (cdns->role == USB_ROLE_HOST)
 591                 return 0;
 592
 593         if (cdns->roles[cdns->role]->resume) {
 594                 spin_lock_irqsave(&cdns->gadget_dev->lock, flags);
 595                 cdns->roles[cdns->role]->resume(cdns, false);
 596                 spin_unlock_irqrestore(&cdns->gadget_dev->lock, flags);
 597         }
 598
 599         pm_runtime_disable(dev);
 600         pm_runtime_set_active(dev);
 601         pm_runtime_enable(dev);
 602
 603         return 0;
 604 }
 605 #endif
 606
 607 static const struct dev_pm_ops cdns3_pm_ops = {
 608         SET_SYSTEM_SLEEP_PM_OPS(cdns3_suspend, cdns3_resume)
 609 };
 610
 611 #ifdef CONFIG_OF
 612 static const struct of_device_id of_cdns3_match[] = {
 613         { .compatible = "cdns,usb3" },
 614         { },
 615 };
 616 MODULE_DEVICE_TABLE(of, of_cdns3_match);
 617 #endif
 618
 619 static struct platform_driver cdns3_driver = {
 620         .probe          = cdns3_probe,
 621         .remove         = cdns3_remove,
 622         .driver         = {
 623                 .name   = "cdns-usb3",
 624                 .of_match_table = of_match_ptr(of_cdns3_match),
 625                 .pm     = &cdns3_pm_ops,
 626         },
 627 };
 628
 629 module_platform_driver(cdns3_driver);
 630
 631 MODULE_ALIAS("platform:cdns3");
 632 MODULE_AUTHOR("Pawel Laszczak <[email protected]>");
 633 MODULE_LICENSE("GPL v2");
 634 MODULE_DESCRIPTION("Cadence USB3 DRD Controller Driver");