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 <peter.chen@nxp.com>
  10  *         Pawel Laszczak <pawell@cadence.com>
  11  *         Roger Quadros <rogerq@ti.com>
  12  */
  13
  14 #include <common.h>
  15 #include <dm.h>
  16 #include <log.h>
  17 #include <dm/device-internal.h>
  18 #include <dm/device_compat.h>
  19 #include <dm/devres.h>
  20 #include <dm/lists.h>
  21 #include <linux/bug.h>
  22 #include <linux/kernel.h>
  23 #include <linux/io.h>
  24 #include <usb.h>
  25 #include <usb/xhci.h>
  26
  27 #include "core.h"
  28 #include "host-export.h"
  29 #include "gadget-export.h"
  30 #include "drd.h"
  31
  32 static int cdns3_idle_init(struct cdns3 *cdns);
  33
  34 struct cdns3_host_priv {
  35         struct xhci_ctrl xhci_ctrl;
  36         struct cdns3 cdns;
  37 };
  38
  39 struct cdns3_gadget_priv {
  40         struct cdns3 cdns;
  41 };
  42
  43 static inline
  44 struct cdns3_role_driver *cdns3_get_current_role_driver(struct cdns3 *cdns)
  45 {
  46         WARN_ON(!cdns->roles[cdns->role]);
  47         return cdns->roles[cdns->role];
  48 }
  49
  50 static int cdns3_role_start(struct cdns3 *cdns, enum usb_role role)
  51 {
  52         int ret;
  53
  54         if (WARN_ON(role > USB_ROLE_DEVICE))
  55                 return 0;
  56
  57         mutex_lock(&cdns->mutex);
  58         cdns->role = role;
  59         mutex_unlock(&cdns->mutex);
  60
  61         if (!cdns->roles[role])
  62                 return -ENXIO;
  63
  64         if (cdns->roles[role]->state == CDNS3_ROLE_STATE_ACTIVE)
  65                 return 0;
  66
  67         mutex_lock(&cdns->mutex);
  68         ret = cdns->roles[role]->start(cdns);
  69         if (!ret)
  70                 cdns->roles[role]->state = CDNS3_ROLE_STATE_ACTIVE;
  71         mutex_unlock(&cdns->mutex);
  72
  73         return ret;
  74 }
  75
  76 static void cdns3_role_stop(struct cdns3 *cdns)
  77 {
  78         enum usb_role role = cdns->role;
  79
  80         if (WARN_ON(role > USB_ROLE_DEVICE))
  81                 return;
  82
  83         if (cdns->roles[role]->state == CDNS3_ROLE_STATE_INACTIVE)
  84                 return;
  85
  86         mutex_lock(&cdns->mutex);
  87         cdns->roles[role]->stop(cdns);
  88         cdns->roles[role]->state = CDNS3_ROLE_STATE_INACTIVE;
  89         mutex_unlock(&cdns->mutex);
  90 }
  91
  92 static void cdns3_exit_roles(struct cdns3 *cdns)
  93 {
  94         cdns3_role_stop(cdns);
  95         cdns3_drd_exit(cdns);
  96 }
  97
  98 static enum usb_role cdsn3_hw_role_state_machine(struct cdns3 *cdns);
  99
 100 /**
 101  * cdns3_core_init_role - initialize role of operation
 102  * @cdns: Pointer to cdns3 structure
 103  *
 104  * Returns 0 on success otherwise negative errno
 105  */
 106 static int cdns3_core_init_role(struct cdns3 *cdns)
 107 {
 108         struct udevice *dev = cdns->dev;
 109         enum usb_dr_mode best_dr_mode;
 110         enum usb_dr_mode dr_mode;
 111         int ret = 0;
 112
 113         dr_mode = usb_get_dr_mode(dev_ofnode(dev));
 114         cdns->role = USB_ROLE_NONE;
 115
 116         /*
 117          * If driver can't read mode by means of usb_get_dr_mode function then
 118          * chooses mode according with Kernel configuration. This setting
 119          * can be restricted later depending on strap pin configuration.
 120          */
 121         if (dr_mode == USB_DR_MODE_UNKNOWN) {
 122                 if (IS_ENABLED(CONFIG_USB_CDNS3_HOST) &&
 123                     IS_ENABLED(CONFIG_USB_CDNS3_GADGET))
 124                         dr_mode = USB_DR_MODE_OTG;
 125                 else if (IS_ENABLED(CONFIG_USB_CDNS3_HOST))
 126                         dr_mode = USB_DR_MODE_HOST;
 127                 else if (IS_ENABLED(CONFIG_USB_CDNS3_GADGET))
 128                         dr_mode = USB_DR_MODE_PERIPHERAL;
 129         }
 130
 131         /*
 132          * At this point cdns->dr_mode contains strap configuration.
 133          * Driver try update this setting considering kernel configuration
 134          */
 135         best_dr_mode = cdns->dr_mode;
 136
 137         ret = cdns3_idle_init(cdns);
 138         if (ret)
 139                 return ret;
 140
 141         if (dr_mode == USB_DR_MODE_OTG) {
 142                 best_dr_mode = cdns->dr_mode;
 143         } else if (cdns->dr_mode == USB_DR_MODE_OTG) {
 144                 best_dr_mode = dr_mode;
 145         } else if (cdns->dr_mode != dr_mode) {
 146                 dev_err(dev, "Incorrect DRD configuration\n");
 147                 return -EINVAL;
 148         }
 149
 150         dr_mode = best_dr_mode;
 151
 152 #if defined(CONFIG_SPL_USB_HOST) || !defined(CONFIG_SPL_BUILD)
 153         if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_HOST) {
 154                 ret = cdns3_host_init(cdns);
 155                 if (ret) {
 156                         dev_err(dev, "Host initialization failed with %d\n",
 157                                 ret);
 158                         goto err;
 159                 }
 160         }
 161 #endif
 162
 163 #if CONFIG_IS_ENABLED(DM_USB_GADGET)
 164         if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_PERIPHERAL) {
 165                 ret = cdns3_gadget_init(cdns);
 166                 if (ret) {
 167                         dev_err(dev, "Device initialization failed with %d\n",
 168                                 ret);
 169                         goto err;
 170                 }
 171         }
 172 #endif
 173
 174         cdns->dr_mode = dr_mode;
 175
 176         ret = cdns3_drd_update_mode(cdns);
 177         if (ret)
 178                 goto err;
 179
 180         if (cdns->dr_mode != USB_DR_MODE_OTG) {
 181                 ret = cdns3_hw_role_switch(cdns);
 182                 if (ret)
 183                         goto err;
 184         }
 185
 186         return ret;
 187 err:
 188         cdns3_exit_roles(cdns);
 189         return ret;
 190 }
 191
 192 /**
 193  * cdsn3_hw_role_state_machine - role switch state machine based on hw events
 194  * @cdns: Pointer to controller structure.
 195  *
 196  * Returns next role to be entered based on hw events.
 197  */
 198 static enum usb_role cdsn3_hw_role_state_machine(struct cdns3 *cdns)
 199 {
 200         enum usb_role role;
 201         int id, vbus;
 202
 203         if (cdns->dr_mode != USB_DR_MODE_OTG)
 204                 goto not_otg;
 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 not_otg:
 243         if (cdns3_is_host(cdns))
 244                 role = USB_ROLE_HOST;
 245         if (cdns3_is_device(cdns))
 246                 role = USB_ROLE_DEVICE;
 247
 248         return role;
 249 }
 250
 251 static int cdns3_idle_role_start(struct cdns3 *cdns)
 252 {
 253         return 0;
 254 }
 255
 256 static void cdns3_idle_role_stop(struct cdns3 *cdns)
 257 {
 258         /* Program Lane swap and bring PHY out of RESET */
 259         generic_phy_reset(&cdns->usb3_phy);
 260 }
 261
 262 static int cdns3_idle_init(struct cdns3 *cdns)
 263 {
 264         struct cdns3_role_driver *rdrv;
 265
 266         rdrv = devm_kzalloc(cdns->dev, sizeof(*rdrv), GFP_KERNEL);
 267         if (!rdrv)
 268                 return -ENOMEM;
 269
 270         rdrv->start = cdns3_idle_role_start;
 271         rdrv->stop = cdns3_idle_role_stop;
 272         rdrv->state = CDNS3_ROLE_STATE_INACTIVE;
 273         rdrv->suspend = NULL;
 274         rdrv->resume = NULL;
 275         rdrv->name = "idle";
 276
 277         cdns->roles[USB_ROLE_NONE] = rdrv;
 278
 279         return 0;
 280 }
 281
 282 /**
 283  * cdns3_hw_role_switch - switch roles based on HW state
 284  * @cdns3: controller
 285  */
 286 int cdns3_hw_role_switch(struct cdns3 *cdns)
 287 {
 288         enum usb_role real_role, current_role;
 289         int ret = 0;
 290
 291         /* Do nothing if role based on syfs. */
 292         if (cdns->role_override)
 293                 return 0;
 294
 295         current_role = cdns->role;
 296         real_role = cdsn3_hw_role_state_machine(cdns);
 297
 298         /* Do nothing if nothing changed */
 299         if (current_role == real_role)
 300                 goto exit;
 301
 302         cdns3_role_stop(cdns);
 303
 304         dev_dbg(cdns->dev, "Switching role %d -> %d", current_role, real_role);
 305
 306         ret = cdns3_role_start(cdns, real_role);
 307         if (ret) {
 308                 /* Back to current role */
 309                 dev_err(cdns->dev, "set %d has failed, back to %d\n",
 310                         real_role, current_role);
 311                 ret = cdns3_role_start(cdns, current_role);
 312                 if (ret)
 313                         dev_err(cdns->dev, "back to %d failed too\n",
 314                                 current_role);
 315         }
 316 exit:
 317         return ret;
 318 }
 319
 320 static int cdns3_probe(struct cdns3 *cdns)
 321 {
 322         struct udevice *dev = cdns->dev;
 323         int ret;
 324
 325         cdns->xhci_regs = dev_remap_addr_name(dev, "xhci");
 326         if (!cdns->xhci_regs)
 327                 return -EINVAL;
 328
 329         cdns->dev_regs = dev_remap_addr_name(dev, "dev");
 330         if (!cdns->dev_regs)
 331                 return -EINVAL;
 332
 333         mutex_init(&cdns->mutex);
 334
 335         ret = generic_phy_get_by_name(dev, "cdns3,usb2-phy", &cdns->usb2_phy);
 336         if (ret)
 337                 dev_warn(dev, "Unable to get USB2 phy (ret %d)\n", ret);
 338
 339         ret = generic_phy_init(&cdns->usb2_phy);
 340         if (ret)
 341                 return ret;
 342
 343         ret = generic_phy_get_by_name(dev, "cdns3,usb3-phy", &cdns->usb3_phy);
 344         if (ret)
 345                 dev_warn(dev, "Unable to get USB3 phy (ret %d)\n", ret);
 346
 347         ret = generic_phy_init(&cdns->usb3_phy);
 348         if (ret)
 349                 return ret;
 350
 351         ret = generic_phy_power_on(&cdns->usb2_phy);
 352         if (ret)
 353                 return ret;
 354
 355         ret = generic_phy_power_on(&cdns->usb3_phy);
 356         if (ret)
 357                 return ret;
 358
 359         ret = cdns3_drd_init(cdns);
 360         if (ret)
 361                 return ret;
 362
 363         ret = cdns3_core_init_role(cdns);
 364         if (ret)
 365                 return ret;
 366
 367         dev_dbg(dev, "Cadence USB3 core: probe succeed\n");
 368
 369         return 0;
 370 }
 371
 372 static int cdns3_remove(struct cdns3 *cdns)
 373 {
 374         cdns3_exit_roles(cdns);
 375         generic_phy_power_off(&cdns->usb2_phy);
 376         generic_phy_power_off(&cdns->usb3_phy);
 377         generic_phy_exit(&cdns->usb2_phy);
 378         generic_phy_exit(&cdns->usb3_phy);
 379         return 0;
 380 }
 381
 382 static const struct udevice_id cdns3_ids[] = {
 383         { .compatible = "cdns,usb3" },
 384         { },
 385 };
 386
 387 int cdns3_bind(struct udevice *parent)
 388 {
 389         enum usb_dr_mode dr_mode;
 390         struct udevice *dev;
 391         const char *driver;
 392         const char *name;
 393         ofnode node;
 394         int ret;
 395
 396         node = ofnode_by_compatible(dev_ofnode(parent), "cdns,usb3");
 397         if (!ofnode_valid(node)) {
 398                 ret = -ENODEV;
 399                 goto fail;
 400         }
 401
 402         name = ofnode_get_name(node);
 403         dr_mode = usb_get_dr_mode(node);
 404
 405         switch (dr_mode) {
 406 #if defined(CONFIG_SPL_USB_HOST) || \
 407         (!defined(CONFIG_SPL_BUILD) && defined(CONFIG_USB_HOST))
 408         case USB_DR_MODE_HOST:
 409                 debug("%s: dr_mode: HOST\n", __func__);
 410                 driver = "cdns-usb3-host";
 411                 break;
 412 #endif
 413 #if CONFIG_IS_ENABLED(DM_USB_GADGET)
 414         case USB_DR_MODE_PERIPHERAL:
 415                 debug("%s: dr_mode: PERIPHERAL\n", __func__);
 416                 driver = "cdns-usb3-peripheral";
 417                 break;
 418 #endif
 419         default:
 420                 printf("%s: unsupported dr_mode\n", __func__);
 421                 ret = -ENODEV;
 422                 goto fail;
 423         };
 424
 425         ret = device_bind_driver_to_node(parent, driver, name, node, &dev);
 426         if (ret) {
 427                 printf("%s: not able to bind usb device mode\n",
 428                        __func__);
 429                 goto fail;
 430         }
 431
 432         return 0;
 433
 434 fail:
 435         /* do not return an error: failing to bind would hang the board */
 436         return 0;
 437 }
 438
 439 #if CONFIG_IS_ENABLED(DM_USB_GADGET)
 440 static int cdns3_gadget_probe(struct udevice *dev)
 441 {
 442         struct cdns3_gadget_priv *priv = dev_get_priv(dev);
 443         struct cdns3 *cdns = &priv->cdns;
 444
 445         cdns->dev = dev;
 446
 447         return cdns3_probe(cdns);
 448 }
 449
 450 static int cdns3_gadget_remove(struct udevice *dev)
 451 {
 452         struct cdns3_gadget_priv *priv = dev_get_priv(dev);
 453         struct cdns3 *cdns = &priv->cdns;
 454
 455         return cdns3_remove(cdns);
 456 }
 457
 458 U_BOOT_DRIVER(cdns_usb3_peripheral) = {
 459         .name   = "cdns-usb3-peripheral",
 460         .id     = UCLASS_USB_GADGET_GENERIC,
 461         .of_match = cdns3_ids,
 462         .probe = cdns3_gadget_probe,
 463         .remove = cdns3_gadget_remove,
 464         .priv_auto      = sizeof(struct cdns3_gadget_priv),
 465         .flags = DM_FLAG_ALLOC_PRIV_DMA,
 466 };
 467 #endif
 468
 469 #if defined(CONFIG_SPL_USB_HOST) || \
 470         (!defined(CONFIG_SPL_BUILD) && defined(CONFIG_USB_HOST))
 471 static int cdns3_host_probe(struct udevice *dev)
 472 {
 473         struct cdns3_host_priv *priv = dev_get_priv(dev);
 474         struct cdns3 *cdns = &priv->cdns;
 475
 476         cdns->dev = dev;
 477
 478         return cdns3_probe(cdns);
 479 }
 480
 481 static int cdns3_host_remove(struct udevice *dev)
 482 {
 483         struct cdns3_host_priv *priv = dev_get_priv(dev);
 484         struct cdns3 *cdns = &priv->cdns;
 485
 486         return cdns3_remove(cdns);
 487 }
 488
 489 U_BOOT_DRIVER(cdns_usb3_host) = {
 490         .name   = "cdns-usb3-host",
 491         .id     = UCLASS_USB,
 492         .of_match = cdns3_ids,
 493         .probe = cdns3_host_probe,
 494         .remove = cdns3_host_remove,
 495         .priv_auto      = sizeof(struct cdns3_host_priv),
 496         .ops = &xhci_usb_ops,
 497         .flags = DM_FLAG_ALLOC_PRIV_DMA,
 498 };
 499 #endif