drivers/usb/dwc2/platform.c

   1 /*
   2  * platform.c - DesignWare HS OTG Controller platform driver
   3  *
   4  * Copyright (C) Matthijs Kooijman <matthijs@stdin.nl>
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions, and the following disclaimer,
  11  *    without modification.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. The names of the above-listed copyright holders may not be used
  16  *    to endorse or promote products derived from this software without
  17  *    specific prior written permission.
  18  *
  19  * ALTERNATIVELY, this software may be distributed under the terms of the
  20  * GNU General Public License ("GPL") as published by the Free Software
  21  * Foundation; either version 2 of the License, or (at your option) any
  22  * later version.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
  25  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  26  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  27  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  28  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  29  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  30  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  31  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  32  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  33  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  34  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35  */
  36
  37 #include <linux/kernel.h>
  38 #include <linux/module.h>
  39 #include <linux/slab.h>
  40 #include <linux/clk.h>
  41 #include <linux/device.h>
  42 #include <linux/dma-mapping.h>
  43 #include <linux/of_device.h>
  44 #include <linux/mutex.h>
  45 #include <linux/platform_device.h>
  46 #include <linux/phy/phy.h>
  47 #include <linux/platform_data/s3c-hsotg.h>
  48 #include <linux/reset.h>
  49
  50 #include <linux/usb/of.h>
  51
  52 #include "core.h"
  53 #include "hcd.h"
  54 #include "debug.h"
  55
  56 static const char dwc2_driver_name[] = "dwc2";
  57
  58 /*
  59  * Check the dr_mode against the module configuration and hardware
  60  * capabilities.
  61  *
  62  * The hardware, module, and dr_mode, can each be set to host, device,
  63  * or otg. Check that all these values are compatible and adjust the
  64  * value of dr_mode if possible.
  65  *
  66  *                      actual
  67  *    HW  MOD dr_mode   dr_mode
  68  *  ------------------------------
  69  *   HST  HST  any    :  HST
  70  *   HST  DEV  any    :  ---
  71  *   HST  OTG  any    :  HST
  72  *
  73  *   DEV  HST  any    :  ---
  74  *   DEV  DEV  any    :  DEV
  75  *   DEV  OTG  any    :  DEV
  76  *
  77  *   OTG  HST  any    :  HST
  78  *   OTG  DEV  any    :  DEV
  79  *   OTG  OTG  any    :  dr_mode
  80  */
  81 static int dwc2_get_dr_mode(struct dwc2_hsotg *hsotg)
  82 {
  83         enum usb_dr_mode mode;
  84
  85         hsotg->dr_mode = usb_get_dr_mode(hsotg->dev);
  86         if (hsotg->dr_mode == USB_DR_MODE_UNKNOWN)
  87                 hsotg->dr_mode = USB_DR_MODE_OTG;
  88
  89         mode = hsotg->dr_mode;
  90
  91         if (dwc2_hw_is_device(hsotg)) {
  92                 if (IS_ENABLED(CONFIG_USB_DWC2_HOST)) {
  93                         dev_err(hsotg->dev,
  94                                 "Controller does not support host mode.\n");
  95                         return -EINVAL;
  96                 }
  97                 mode = USB_DR_MODE_PERIPHERAL;
  98         } else if (dwc2_hw_is_host(hsotg)) {
  99                 if (IS_ENABLED(CONFIG_USB_DWC2_PERIPHERAL)) {
 100                         dev_err(hsotg->dev,
 101                                 "Controller does not support device mode.\n");
 102                         return -EINVAL;
 103                 }
 104                 mode = USB_DR_MODE_HOST;
 105         } else {
 106                 if (IS_ENABLED(CONFIG_USB_DWC2_HOST))
 107                         mode = USB_DR_MODE_HOST;
 108                 else if (IS_ENABLED(CONFIG_USB_DWC2_PERIPHERAL))
 109                         mode = USB_DR_MODE_PERIPHERAL;
 110         }
 111
 112         if (mode != hsotg->dr_mode) {
 113                 dev_warn(hsotg->dev,
 114                          "Configuration mismatch. dr_mode forced to %s\n",
 115                         mode == USB_DR_MODE_HOST ? "host" : "device");
 116
 117                 hsotg->dr_mode = mode;
 118         }
 119
 120         return 0;
 121 }
 122
 123 static int __dwc2_lowlevel_hw_enable(struct dwc2_hsotg *hsotg)
 124 {
 125         struct platform_device *pdev = to_platform_device(hsotg->dev);
 126         int ret;
 127
 128         ret = regulator_bulk_enable(ARRAY_SIZE(hsotg->supplies),
 129                                     hsotg->supplies);
 130         if (ret)
 131                 return ret;
 132
 133         if (hsotg->clk) {
 134                 ret = clk_prepare_enable(hsotg->clk);
 135                 if (ret)
 136                         return ret;
 137         }
 138
 139         if (hsotg->uphy) {
 140                 ret = usb_phy_init(hsotg->uphy);
 141         } else if (hsotg->plat && hsotg->plat->phy_init) {
 142                 ret = hsotg->plat->phy_init(pdev, hsotg->plat->phy_type);
 143         } else {
 144                 ret = phy_power_on(hsotg->phy);
 145                 if (ret == 0)
 146                         ret = phy_init(hsotg->phy);
 147         }
 148
 149         return ret;
 150 }
 151
 152 /**
 153  * dwc2_lowlevel_hw_enable - enable platform lowlevel hw resources
 154  * @hsotg: The driver state
 155  *
 156  * A wrapper for platform code responsible for controlling
 157  * low-level USB platform resources (phy, clock, regulators)
 158  */
 159 int dwc2_lowlevel_hw_enable(struct dwc2_hsotg *hsotg)
 160 {
 161         int ret = __dwc2_lowlevel_hw_enable(hsotg);
 162
 163         if (ret == 0)
 164                 hsotg->ll_hw_enabled = true;
 165         return ret;
 166 }
 167
 168 static int __dwc2_lowlevel_hw_disable(struct dwc2_hsotg *hsotg)
 169 {
 170         struct platform_device *pdev = to_platform_device(hsotg->dev);
 171         int ret = 0;
 172
 173         if (hsotg->uphy) {
 174                 usb_phy_shutdown(hsotg->uphy);
 175         } else if (hsotg->plat && hsotg->plat->phy_exit) {
 176                 ret = hsotg->plat->phy_exit(pdev, hsotg->plat->phy_type);
 177         } else {
 178                 ret = phy_exit(hsotg->phy);
 179                 if (ret == 0)
 180                         ret = phy_power_off(hsotg->phy);
 181         }
 182         if (ret)
 183                 return ret;
 184
 185         if (hsotg->clk)
 186                 clk_disable_unprepare(hsotg->clk);
 187
 188         ret = regulator_bulk_disable(ARRAY_SIZE(hsotg->supplies),
 189                                      hsotg->supplies);
 190
 191         return ret;
 192 }
 193
 194 /**
 195  * dwc2_lowlevel_hw_disable - disable platform lowlevel hw resources
 196  * @hsotg: The driver state
 197  *
 198  * A wrapper for platform code responsible for controlling
 199  * low-level USB platform resources (phy, clock, regulators)
 200  */
 201 int dwc2_lowlevel_hw_disable(struct dwc2_hsotg *hsotg)
 202 {
 203         int ret = __dwc2_lowlevel_hw_disable(hsotg);
 204
 205         if (ret == 0)
 206                 hsotg->ll_hw_enabled = false;
 207         return ret;
 208 }
 209
 210 static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg)
 211 {
 212         int i, ret;
 213
 214         hsotg->reset = devm_reset_control_get_optional(hsotg->dev, "dwc2");
 215         if (IS_ERR(hsotg->reset)) {
 216                 ret = PTR_ERR(hsotg->reset);
 217                 switch (ret) {
 218                 case -ENOENT:
 219                 case -ENOTSUPP:
 220                         hsotg->reset = NULL;
 221                         break;
 222                 default:
 223                         dev_err(hsotg->dev, "error getting reset control %d\n",
 224                                 ret);
 225                         return ret;
 226                 }
 227         }
 228
 229         if (hsotg->reset)
 230                 reset_control_deassert(hsotg->reset);
 231
 232         /* Set default UTMI width */
 233         hsotg->phyif = GUSBCFG_PHYIF16;
 234
 235         /*
 236          * Attempt to find a generic PHY, then look for an old style
 237          * USB PHY and then fall back to pdata
 238          */
 239         hsotg->phy = devm_phy_get(hsotg->dev, "usb2-phy");
 240         if (IS_ERR(hsotg->phy)) {
 241                 ret = PTR_ERR(hsotg->phy);
 242                 switch (ret) {
 243                 case -ENODEV:
 244                 case -ENOSYS:
 245                         hsotg->phy = NULL;
 246                         break;
 247                 case -EPROBE_DEFER:
 248                         return ret;
 249                 default:
 250                         dev_err(hsotg->dev, "error getting phy %d\n", ret);
 251                         return ret;
 252                 }
 253         }
 254
 255         if (!hsotg->phy) {
 256                 hsotg->uphy = devm_usb_get_phy(hsotg->dev, USB_PHY_TYPE_USB2);
 257                 if (IS_ERR(hsotg->uphy)) {
 258                         ret = PTR_ERR(hsotg->uphy);
 259                         switch (ret) {
 260                         case -ENODEV:
 261                         case -ENXIO:
 262                                 hsotg->uphy = NULL;
 263                                 break;
 264                         case -EPROBE_DEFER:
 265                                 return ret;
 266                         default:
 267                                 dev_err(hsotg->dev, "error getting usb phy %d\n",
 268                                         ret);
 269                                 return ret;
 270                         }
 271                 }
 272         }
 273
 274         hsotg->plat = dev_get_platdata(hsotg->dev);
 275
 276         if (hsotg->phy) {
 277                 /*
 278                  * If using the generic PHY framework, check if the PHY bus
 279                  * width is 8-bit and set the phyif appropriately.
 280                  */
 281                 if (phy_get_bus_width(hsotg->phy) == 8)
 282                         hsotg->phyif = GUSBCFG_PHYIF8;
 283         }
 284
 285         /* Clock */
 286         hsotg->clk = devm_clk_get(hsotg->dev, "otg");
 287         if (IS_ERR(hsotg->clk)) {
 288                 hsotg->clk = NULL;
 289                 dev_dbg(hsotg->dev, "cannot get otg clock\n");
 290         }
 291
 292         /* Regulators */
 293         for (i = 0; i < ARRAY_SIZE(hsotg->supplies); i++)
 294                 hsotg->supplies[i].supply = dwc2_hsotg_supply_names[i];
 295
 296         ret = devm_regulator_bulk_get(hsotg->dev, ARRAY_SIZE(hsotg->supplies),
 297                                       hsotg->supplies);
 298         if (ret) {
 299                 dev_err(hsotg->dev, "failed to request supplies: %d\n", ret);
 300                 return ret;
 301         }
 302         return 0;
 303 }
 304
 305 /**
 306  * dwc2_driver_remove() - Called when the DWC_otg core is unregistered with the
 307  * DWC_otg driver
 308  *
 309  * @dev: Platform device
 310  *
 311  * This routine is called, for example, when the rmmod command is executed. The
 312  * device may or may not be electrically present. If it is present, the driver
 313  * stops device processing. Any resources used on behalf of this device are
 314  * freed.
 315  */
 316 static int dwc2_driver_remove(struct platform_device *dev)
 317 {
 318         struct dwc2_hsotg *hsotg = platform_get_drvdata(dev);
 319
 320         dwc2_debugfs_exit(hsotg);
 321         if (hsotg->hcd_enabled)
 322                 dwc2_hcd_remove(hsotg);
 323         if (hsotg->gadget_enabled)
 324                 dwc2_hsotg_remove(hsotg);
 325
 326         if (hsotg->ll_hw_enabled)
 327                 dwc2_lowlevel_hw_disable(hsotg);
 328
 329         if (hsotg->reset)
 330                 reset_control_assert(hsotg->reset);
 331
 332         return 0;
 333 }
 334
 335 /**
 336  * dwc2_driver_shutdown() - Called on device shutdown
 337  *
 338  * @dev: Platform device
 339  *
 340  * In specific conditions (involving usb hubs) dwc2 devices can create a
 341  * lot of interrupts, even to the point of overwhelming devices running
 342  * at low frequencies. Some devices need to do special clock handling
 343  * at shutdown-time which may bring the system clock below the threshold
 344  * of being able to handle the dwc2 interrupts. Disabling dwc2-irqs
 345  * prevents reboots/poweroffs from getting stuck in such cases.
 346  */
 347 static void dwc2_driver_shutdown(struct platform_device *dev)
 348 {
 349         struct dwc2_hsotg *hsotg = platform_get_drvdata(dev);
 350
 351         disable_irq(hsotg->irq);
 352 }
 353
 354 /**
 355  * dwc2_driver_probe() - Called when the DWC_otg core is bound to the DWC_otg
 356  * driver
 357  *
 358  * @dev: Platform device
 359  *
 360  * This routine creates the driver components required to control the device
 361  * (core, HCD, and PCD) and initializes the device. The driver components are
 362  * stored in a dwc2_hsotg structure. A reference to the dwc2_hsotg is saved
 363  * in the device private data. This allows the driver to access the dwc2_hsotg
 364  * structure on subsequent calls to driver methods for this device.
 365  */
 366 static int dwc2_driver_probe(struct platform_device *dev)
 367 {
 368         struct dwc2_hsotg *hsotg;
 369         struct resource *res;
 370         int retval;
 371
 372         hsotg = devm_kzalloc(&dev->dev, sizeof(*hsotg), GFP_KERNEL);
 373         if (!hsotg)
 374                 return -ENOMEM;
 375
 376         hsotg->dev = &dev->dev;
 377
 378         /*
 379          * Use reasonable defaults so platforms don't have to provide these.
 380          */
 381         if (!dev->dev.dma_mask)
 382                 dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
 383         retval = dma_set_coherent_mask(&dev->dev, DMA_BIT_MASK(32));
 384         if (retval)
 385                 return retval;
 386
 387         res = platform_get_resource(dev, IORESOURCE_MEM, 0);
 388         hsotg->regs = devm_ioremap_resource(&dev->dev, res);
 389         if (IS_ERR(hsotg->regs))
 390                 return PTR_ERR(hsotg->regs);
 391
 392         dev_dbg(&dev->dev, "mapped PA %08lx to VA %p\n",
 393                 (unsigned long)res->start, hsotg->regs);
 394
 395         retval = dwc2_lowlevel_hw_init(hsotg);
 396         if (retval)
 397                 return retval;
 398
 399         spin_lock_init(&hsotg->lock);
 400
 401         hsotg->irq = platform_get_irq(dev, 0);
 402         if (hsotg->irq < 0) {
 403                 dev_err(&dev->dev, "missing IRQ resource\n");
 404                 return hsotg->irq;
 405         }
 406
 407         dev_dbg(hsotg->dev, "registering common handler for irq%d\n",
 408                 hsotg->irq);
 409         retval = devm_request_irq(hsotg->dev, hsotg->irq,
 410                                   dwc2_handle_common_intr, IRQF_SHARED,
 411                                   dev_name(hsotg->dev), hsotg);
 412         if (retval)
 413                 return retval;
 414
 415         retval = dwc2_lowlevel_hw_enable(hsotg);
 416         if (retval)
 417                 return retval;
 418
 419         retval = dwc2_get_dr_mode(hsotg);
 420         if (retval)
 421                 goto error;
 422
 423         /*
 424          * Reset before dwc2_get_hwparams() then it could get power-on real
 425          * reset value form registers.
 426          */
 427         dwc2_core_reset_and_force_dr_mode(hsotg);
 428
 429         /* Detect config values from hardware */
 430         retval = dwc2_get_hwparams(hsotg);
 431         if (retval)
 432                 goto error;
 433
 434         dwc2_force_dr_mode(hsotg);
 435
 436         retval = dwc2_init_params(hsotg);
 437         if (retval)
 438                 goto error;
 439
 440         if (hsotg->dr_mode != USB_DR_MODE_HOST) {
 441                 retval = dwc2_gadget_init(hsotg, hsotg->irq);
 442                 if (retval)
 443                         goto error;
 444                 hsotg->gadget_enabled = 1;
 445         }
 446
 447         if (hsotg->dr_mode != USB_DR_MODE_PERIPHERAL) {
 448                 retval = dwc2_hcd_init(hsotg);
 449                 if (retval) {
 450                         if (hsotg->gadget_enabled)
 451                                 dwc2_hsotg_remove(hsotg);
 452                         goto error;
 453                 }
 454                 hsotg->hcd_enabled = 1;
 455         }
 456
 457         platform_set_drvdata(dev, hsotg);
 458
 459         dwc2_debugfs_init(hsotg);
 460
 461         /* Gadget code manages lowlevel hw on its own */
 462         if (hsotg->dr_mode == USB_DR_MODE_PERIPHERAL)
 463                 dwc2_lowlevel_hw_disable(hsotg);
 464
 465         return 0;
 466
 467 error:
 468         dwc2_lowlevel_hw_disable(hsotg);
 469         return retval;
 470 }
 471
 472 static int __maybe_unused dwc2_suspend(struct device *dev)
 473 {
 474         struct dwc2_hsotg *dwc2 = dev_get_drvdata(dev);
 475         int ret = 0;
 476
 477         if (dwc2_is_device_mode(dwc2))
 478                 dwc2_hsotg_suspend(dwc2);
 479
 480         if (dwc2->ll_hw_enabled)
 481                 ret = __dwc2_lowlevel_hw_disable(dwc2);
 482
 483         return ret;
 484 }
 485
 486 static int __maybe_unused dwc2_resume(struct device *dev)
 487 {
 488         struct dwc2_hsotg *dwc2 = dev_get_drvdata(dev);
 489         int ret = 0;
 490
 491         if (dwc2->ll_hw_enabled) {
 492                 ret = __dwc2_lowlevel_hw_enable(dwc2);
 493                 if (ret)
 494                         return ret;
 495         }
 496
 497         if (dwc2_is_device_mode(dwc2))
 498                 ret = dwc2_hsotg_resume(dwc2);
 499
 500         return ret;
 501 }
 502
 503 static const struct dev_pm_ops dwc2_dev_pm_ops = {
 504         SET_SYSTEM_SLEEP_PM_OPS(dwc2_suspend, dwc2_resume)
 505 };
 506
 507 static struct platform_driver dwc2_platform_driver = {
 508         .driver = {
 509                 .name = dwc2_driver_name,
 510                 .of_match_table = dwc2_of_match_table,
 511                 .pm = &dwc2_dev_pm_ops,
 512         },
 513         .probe = dwc2_driver_probe,
 514         .remove = dwc2_driver_remove,
 515         .shutdown = dwc2_driver_shutdown,
 516 };
 517
 518 module_platform_driver(dwc2_platform_driver);
 519
 520 MODULE_DESCRIPTION("DESIGNWARE HS OTG Platform Glue");
 521 MODULE_AUTHOR("Matthijs Kooijman <matthijs@stdin.nl>");
 522 MODULE_LICENSE("Dual BSD/GPL");