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 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         regs = devm_platform_ioremap_resource_byname(pdev, "dev");
 427         if (IS_ERR(regs))
 428                 return PTR_ERR(regs);
 429         cdns->dev_regs  = regs;
 430
 431         cdns->otg_irq = platform_get_irq_byname(pdev, "otg");
 432         if (cdns->otg_irq == -EPROBE_DEFER)
 433                 return cdns->otg_irq;
 434
 435         if (cdns->otg_irq < 0) {
 436                 dev_err(dev, "couldn't get otg irq\n");
 437                 return cdns->otg_irq;
 438         }
 439
 440         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "otg");
 441         if (!res) {
 442                 dev_err(dev, "couldn't get otg resource\n");
 443                 return -ENXIO;
 444         }
 445
 446         cdns->otg_res = *res;
 447
 448         mutex_init(&cdns->mutex);
 449
 450         cdns->usb2_phy = devm_phy_optional_get(dev, "cdns3,usb2-phy");
 451         if (IS_ERR(cdns->usb2_phy))
 452                 return PTR_ERR(cdns->usb2_phy);
 453
 454         ret = phy_init(cdns->usb2_phy);
 455         if (ret)
 456                 return ret;
 457
 458         cdns->usb3_phy = devm_phy_optional_get(dev, "cdns3,usb3-phy");
 459         if (IS_ERR(cdns->usb3_phy))
 460                 return PTR_ERR(cdns->usb3_phy);
 461
 462         ret = phy_init(cdns->usb3_phy);
 463         if (ret)
 464                 goto err1;
 465
 466         ret = phy_power_on(cdns->usb2_phy);
 467         if (ret)
 468                 goto err2;
 469
 470         ret = phy_power_on(cdns->usb3_phy);
 471         if (ret)
 472                 goto err3;
 473
 474         sw_desc.set = cdns3_role_set;
 475         sw_desc.get = cdns3_role_get;
 476         sw_desc.allow_userspace_control = true;
 477         sw_desc.driver_data = cdns;
 478         if (device_property_read_bool(dev, "usb-role-switch"))
 479                 sw_desc.fwnode = dev->fwnode;
 480
 481         cdns->role_sw = usb_role_switch_register(dev, &sw_desc);
 482         if (IS_ERR(cdns->role_sw)) {
 483                 ret = PTR_ERR(cdns->role_sw);
 484                 dev_warn(dev, "Unable to register Role Switch\n");
 485                 goto err4;
 486         }
 487
 488         ret = cdns3_drd_init(cdns);
 489         if (ret)
 490                 goto err5;
 491
 492         ret = cdns3_core_init_role(cdns);
 493         if (ret)
 494                 goto err5;
 495
 496         device_set_wakeup_capable(dev, true);
 497         pm_runtime_set_active(dev);
 498         pm_runtime_enable(dev);
 499
 500         /*
 501          * The controller needs less time between bus and controller suspend,
 502          * and we also needs a small delay to avoid frequently entering low
 503          * power mode.
 504          */
 505         pm_runtime_set_autosuspend_delay(dev, 20);
 506         pm_runtime_mark_last_busy(dev);
 507         pm_runtime_use_autosuspend(dev);
 508         dev_dbg(dev, "Cadence USB3 core: probe succeed\n");
 509
 510         return 0;
 511 err5:
 512         cdns3_drd_exit(cdns);
 513         usb_role_switch_unregister(cdns->role_sw);
 514 err4:
 515         phy_power_off(cdns->usb3_phy);
 516
 517 err3:
 518         phy_power_off(cdns->usb2_phy);
 519 err2:
 520         phy_exit(cdns->usb3_phy);
 521 err1:
 522         phy_exit(cdns->usb2_phy);
 523
 524         return ret;
 525 }
 526
 527 /**
 528  * cdns3_remove - unbind drd driver and clean up
 529  * @pdev: Pointer to Linux platform device
 530  *
 531  * Returns 0 on success otherwise negative errno
 532  */
 533 static int cdns3_remove(struct platform_device *pdev)
 534 {
 535         struct cdns3 *cdns = platform_get_drvdata(pdev);
 536
 537         pm_runtime_get_sync(&pdev->dev);
 538         pm_runtime_disable(&pdev->dev);
 539         pm_runtime_put_noidle(&pdev->dev);
 540         cdns3_exit_roles(cdns);
 541         usb_role_switch_unregister(cdns->role_sw);
 542         phy_power_off(cdns->usb2_phy);
 543         phy_power_off(cdns->usb3_phy);
 544         phy_exit(cdns->usb2_phy);
 545         phy_exit(cdns->usb3_phy);
 546         return 0;
 547 }
 548
 549 #ifdef CONFIG_PM_SLEEP
 550
 551 static int cdns3_suspend(struct device *dev)
 552 {
 553         struct cdns3 *cdns = dev_get_drvdata(dev);
 554         unsigned long flags;
 555
 556         if (cdns->role == USB_ROLE_HOST)
 557                 return 0;
 558
 559         if (pm_runtime_status_suspended(dev))
 560                 pm_runtime_resume(dev);
 561
 562         if (cdns->roles[cdns->role]->suspend) {
 563                 spin_lock_irqsave(&cdns->gadget_dev->lock, flags);
 564                 cdns->roles[cdns->role]->suspend(cdns, false);
 565                 spin_unlock_irqrestore(&cdns->gadget_dev->lock, flags);
 566         }
 567
 568         return 0;
 569 }
 570
 571 static int cdns3_resume(struct device *dev)
 572 {
 573         struct cdns3 *cdns = dev_get_drvdata(dev);
 574         unsigned long flags;
 575
 576         if (cdns->role == USB_ROLE_HOST)
 577                 return 0;
 578
 579         if (cdns->roles[cdns->role]->resume) {
 580                 spin_lock_irqsave(&cdns->gadget_dev->lock, flags);
 581                 cdns->roles[cdns->role]->resume(cdns, false);
 582                 spin_unlock_irqrestore(&cdns->gadget_dev->lock, flags);
 583         }
 584
 585         pm_runtime_disable(dev);
 586         pm_runtime_set_active(dev);
 587         pm_runtime_enable(dev);
 588
 589         return 0;
 590 }
 591 #endif
 592
 593 static const struct dev_pm_ops cdns3_pm_ops = {
 594         SET_SYSTEM_SLEEP_PM_OPS(cdns3_suspend, cdns3_resume)
 595 };
 596
 597 #ifdef CONFIG_OF
 598 static const struct of_device_id of_cdns3_match[] = {
 599         { .compatible = "cdns,usb3" },
 600         { },
 601 };
 602 MODULE_DEVICE_TABLE(of, of_cdns3_match);
 603 #endif
 604
 605 static struct platform_driver cdns3_driver = {
 606         .probe          = cdns3_probe,
 607         .remove         = cdns3_remove,
 608         .driver         = {
 609                 .name   = "cdns-usb3",
 610                 .of_match_table = of_match_ptr(of_cdns3_match),
 611                 .pm     = &cdns3_pm_ops,
 612         },
 613 };
 614
 615 module_platform_driver(cdns3_driver);
 616
 617 MODULE_ALIAS("platform:cdns3");
 618 MODULE_AUTHOR("Pawel Laszczak <[email protected]>");
 619 MODULE_LICENSE("GPL v2");
 620 MODULE_DESCRIPTION("Cadence USB3 DRD Controller Driver");