1 // SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause) 2 /* 3 * platform.c - DesignWare HS OTG Controller platform driver 4 * 5 * Copyright (C) Matthijs Kooijman <matthijs@stdin.nl> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions, and the following disclaimer, 12 * without modification. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. The names of the above-listed copyright holders may not be used 17 * to endorse or promote products derived from this software without 18 * specific prior written permission. 19 * 20 * ALTERNATIVELY, this software may be distributed under the terms of the 21 * GNU General Public License ("GPL") as published by the Free Software 22 * Foundation; either version 2 of the License, or (at your option) any 23 * later version. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS 26 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 27 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR 29 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 30 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 31 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 32 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 33 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 34 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 35 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 #include <linux/kernel.h> 39 #include <linux/module.h> 40 #include <linux/slab.h> 41 #include <linux/clk.h> 42 #include <linux/device.h> 43 #include <linux/dma-mapping.h> 44 #include <linux/of_device.h> 45 #include <linux/mutex.h> 46 #include <linux/platform_device.h> 47 #include <linux/phy/phy.h> 48 #include <linux/platform_data/s3c-hsotg.h> 49 #include <linux/reset.h> 50 51 #include <linux/usb/of.h> 52 53 #include "core.h" 54 #include "hcd.h" 55 #include "debug.h" 56 57 static const char dwc2_driver_name[] = "dwc2"; 58 59 /* 60 * Check the dr_mode against the module configuration and hardware 61 * capabilities. 62 * 63 * The hardware, module, and dr_mode, can each be set to host, device, 64 * or otg. Check that all these values are compatible and adjust the 65 * value of dr_mode if possible. 66 * 67 * actual 68 * HW MOD dr_mode dr_mode 69 * ------------------------------ 70 * HST HST any : HST 71 * HST DEV any : --- 72 * HST OTG any : HST 73 * 74 * DEV HST any : --- 75 * DEV DEV any : DEV 76 * DEV OTG any : DEV 77 * 78 * OTG HST any : HST 79 * OTG DEV any : DEV 80 * OTG OTG any : dr_mode 81 */ 82 static int dwc2_get_dr_mode(struct dwc2_hsotg *hsotg) 83 { 84 enum usb_dr_mode mode; 85 86 hsotg->dr_mode = usb_get_dr_mode(hsotg->dev); 87 if (hsotg->dr_mode == USB_DR_MODE_UNKNOWN) 88 hsotg->dr_mode = USB_DR_MODE_OTG; 89 90 mode = hsotg->dr_mode; 91 92 if (dwc2_hw_is_device(hsotg)) { 93 if (IS_ENABLED(CONFIG_USB_DWC2_HOST)) { 94 dev_err(hsotg->dev, 95 "Controller does not support host mode.\n"); 96 return -EINVAL; 97 } 98 mode = USB_DR_MODE_PERIPHERAL; 99 } else if (dwc2_hw_is_host(hsotg)) { 100 if (IS_ENABLED(CONFIG_USB_DWC2_PERIPHERAL)) { 101 dev_err(hsotg->dev, 102 "Controller does not support device mode.\n"); 103 return -EINVAL; 104 } 105 mode = USB_DR_MODE_HOST; 106 } else { 107 if (IS_ENABLED(CONFIG_USB_DWC2_HOST)) 108 mode = USB_DR_MODE_HOST; 109 else if (IS_ENABLED(CONFIG_USB_DWC2_PERIPHERAL)) 110 mode = USB_DR_MODE_PERIPHERAL; 111 } 112 113 if (mode != hsotg->dr_mode) { 114 dev_warn(hsotg->dev, 115 "Configuration mismatch. dr_mode forced to %s\n", 116 mode == USB_DR_MODE_HOST ? "host" : "device"); 117 118 hsotg->dr_mode = mode; 119 } 120 121 return 0; 122 } 123 124 static int __dwc2_lowlevel_hw_enable(struct dwc2_hsotg *hsotg) 125 { 126 struct platform_device *pdev = to_platform_device(hsotg->dev); 127 int ret; 128 129 ret = regulator_bulk_enable(ARRAY_SIZE(hsotg->supplies), 130 hsotg->supplies); 131 if (ret) 132 return ret; 133 134 if (hsotg->clk) { 135 ret = clk_prepare_enable(hsotg->clk); 136 if (ret) 137 return ret; 138 } 139 140 if (hsotg->uphy) { 141 ret = usb_phy_init(hsotg->uphy); 142 } else if (hsotg->plat && hsotg->plat->phy_init) { 143 ret = hsotg->plat->phy_init(pdev, hsotg->plat->phy_type); 144 } else { 145 ret = phy_power_on(hsotg->phy); 146 if (ret == 0) 147 ret = phy_init(hsotg->phy); 148 } 149 150 return ret; 151 } 152 153 /** 154 * dwc2_lowlevel_hw_enable - enable platform lowlevel hw resources 155 * @hsotg: The driver state 156 * 157 * A wrapper for platform code responsible for controlling 158 * low-level USB platform resources (phy, clock, regulators) 159 */ 160 int dwc2_lowlevel_hw_enable(struct dwc2_hsotg *hsotg) 161 { 162 int ret = __dwc2_lowlevel_hw_enable(hsotg); 163 164 if (ret == 0) 165 hsotg->ll_hw_enabled = true; 166 return ret; 167 } 168 169 static int __dwc2_lowlevel_hw_disable(struct dwc2_hsotg *hsotg) 170 { 171 struct platform_device *pdev = to_platform_device(hsotg->dev); 172 int ret = 0; 173 174 if (hsotg->uphy) { 175 usb_phy_shutdown(hsotg->uphy); 176 } else if (hsotg->plat && hsotg->plat->phy_exit) { 177 ret = hsotg->plat->phy_exit(pdev, hsotg->plat->phy_type); 178 } else { 179 ret = phy_exit(hsotg->phy); 180 if (ret == 0) 181 ret = phy_power_off(hsotg->phy); 182 } 183 if (ret) 184 return ret; 185 186 if (hsotg->clk) 187 clk_disable_unprepare(hsotg->clk); 188 189 ret = regulator_bulk_disable(ARRAY_SIZE(hsotg->supplies), 190 hsotg->supplies); 191 192 return ret; 193 } 194 195 /** 196 * dwc2_lowlevel_hw_disable - disable platform lowlevel hw resources 197 * @hsotg: The driver state 198 * 199 * A wrapper for platform code responsible for controlling 200 * low-level USB platform resources (phy, clock, regulators) 201 */ 202 int dwc2_lowlevel_hw_disable(struct dwc2_hsotg *hsotg) 203 { 204 int ret = __dwc2_lowlevel_hw_disable(hsotg); 205 206 if (ret == 0) 207 hsotg->ll_hw_enabled = false; 208 return ret; 209 } 210 211 static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg) 212 { 213 int i, ret; 214 215 hsotg->reset = devm_reset_control_get_optional(hsotg->dev, "dwc2"); 216 if (IS_ERR(hsotg->reset)) { 217 ret = PTR_ERR(hsotg->reset); 218 dev_err(hsotg->dev, "error getting reset control %d\n", ret); 219 return ret; 220 } 221 222 reset_control_deassert(hsotg->reset); 223 224 hsotg->reset_ecc = devm_reset_control_get_optional(hsotg->dev, "dwc2-ecc"); 225 if (IS_ERR(hsotg->reset_ecc)) { 226 ret = PTR_ERR(hsotg->reset_ecc); 227 dev_err(hsotg->dev, "error getting reset control for ecc %d\n", ret); 228 return ret; 229 } 230 231 reset_control_deassert(hsotg->reset_ecc); 232 233 /* 234 * Attempt to find a generic PHY, then look for an old style 235 * USB PHY and then fall back to pdata 236 */ 237 hsotg->phy = devm_phy_get(hsotg->dev, "usb2-phy"); 238 if (IS_ERR(hsotg->phy)) { 239 ret = PTR_ERR(hsotg->phy); 240 switch (ret) { 241 case -ENODEV: 242 case -ENOSYS: 243 hsotg->phy = NULL; 244 break; 245 case -EPROBE_DEFER: 246 return ret; 247 default: 248 dev_err(hsotg->dev, "error getting phy %d\n", ret); 249 return ret; 250 } 251 } 252 253 if (!hsotg->phy) { 254 hsotg->uphy = devm_usb_get_phy(hsotg->dev, USB_PHY_TYPE_USB2); 255 if (IS_ERR(hsotg->uphy)) { 256 ret = PTR_ERR(hsotg->uphy); 257 switch (ret) { 258 case -ENODEV: 259 case -ENXIO: 260 hsotg->uphy = NULL; 261 break; 262 case -EPROBE_DEFER: 263 return ret; 264 default: 265 dev_err(hsotg->dev, "error getting usb phy %d\n", 266 ret); 267 return ret; 268 } 269 } 270 } 271 272 hsotg->plat = dev_get_platdata(hsotg->dev); 273 274 /* Clock */ 275 hsotg->clk = devm_clk_get_optional(hsotg->dev, "otg"); 276 if (IS_ERR(hsotg->clk)) { 277 dev_err(hsotg->dev, "cannot get otg clock\n"); 278 return PTR_ERR(hsotg->clk); 279 } 280 281 /* Regulators */ 282 for (i = 0; i < ARRAY_SIZE(hsotg->supplies); i++) 283 hsotg->supplies[i].supply = dwc2_hsotg_supply_names[i]; 284 285 ret = devm_regulator_bulk_get(hsotg->dev, ARRAY_SIZE(hsotg->supplies), 286 hsotg->supplies); 287 if (ret) { 288 dev_err(hsotg->dev, "failed to request supplies: %d\n", ret); 289 return ret; 290 } 291 return 0; 292 } 293 294 /** 295 * dwc2_driver_remove() - Called when the DWC_otg core is unregistered with the 296 * DWC_otg driver 297 * 298 * @dev: Platform device 299 * 300 * This routine is called, for example, when the rmmod command is executed. The 301 * device may or may not be electrically present. If it is present, the driver 302 * stops device processing. Any resources used on behalf of this device are 303 * freed. 304 */ 305 static int dwc2_driver_remove(struct platform_device *dev) 306 { 307 struct dwc2_hsotg *hsotg = platform_get_drvdata(dev); 308 309 dwc2_debugfs_exit(hsotg); 310 if (hsotg->hcd_enabled) 311 dwc2_hcd_remove(hsotg); 312 if (hsotg->gadget_enabled) 313 dwc2_hsotg_remove(hsotg); 314 315 if (hsotg->ll_hw_enabled) 316 dwc2_lowlevel_hw_disable(hsotg); 317 318 reset_control_assert(hsotg->reset); 319 reset_control_assert(hsotg->reset_ecc); 320 321 return 0; 322 } 323 324 /** 325 * dwc2_driver_shutdown() - Called on device shutdown 326 * 327 * @dev: Platform device 328 * 329 * In specific conditions (involving usb hubs) dwc2 devices can create a 330 * lot of interrupts, even to the point of overwhelming devices running 331 * at low frequencies. Some devices need to do special clock handling 332 * at shutdown-time which may bring the system clock below the threshold 333 * of being able to handle the dwc2 interrupts. Disabling dwc2-irqs 334 * prevents reboots/poweroffs from getting stuck in such cases. 335 */ 336 static void dwc2_driver_shutdown(struct platform_device *dev) 337 { 338 struct dwc2_hsotg *hsotg = platform_get_drvdata(dev); 339 340 disable_irq(hsotg->irq); 341 } 342 343 /** 344 * dwc2_check_core_endianness() - Returns true if core and AHB have 345 * opposite endianness. 346 * @hsotg: Programming view of the DWC_otg controller. 347 */ 348 static bool dwc2_check_core_endianness(struct dwc2_hsotg *hsotg) 349 { 350 u32 snpsid; 351 352 snpsid = ioread32(hsotg->regs + GSNPSID); 353 if ((snpsid & GSNPSID_ID_MASK) == DWC2_OTG_ID || 354 (snpsid & GSNPSID_ID_MASK) == DWC2_FS_IOT_ID || 355 (snpsid & GSNPSID_ID_MASK) == DWC2_HS_IOT_ID) 356 return false; 357 return true; 358 } 359 360 /** 361 * dwc2_driver_probe() - Called when the DWC_otg core is bound to the DWC_otg 362 * driver 363 * 364 * @dev: Platform device 365 * 366 * This routine creates the driver components required to control the device 367 * (core, HCD, and PCD) and initializes the device. The driver components are 368 * stored in a dwc2_hsotg structure. A reference to the dwc2_hsotg is saved 369 * in the device private data. This allows the driver to access the dwc2_hsotg 370 * structure on subsequent calls to driver methods for this device. 371 */ 372 static int dwc2_driver_probe(struct platform_device *dev) 373 { 374 struct dwc2_hsotg *hsotg; 375 struct resource *res; 376 int retval; 377 378 hsotg = devm_kzalloc(&dev->dev, sizeof(*hsotg), GFP_KERNEL); 379 if (!hsotg) 380 return -ENOMEM; 381 382 hsotg->dev = &dev->dev; 383 384 /* 385 * Use reasonable defaults so platforms don't have to provide these. 386 */ 387 if (!dev->dev.dma_mask) 388 dev->dev.dma_mask = &dev->dev.coherent_dma_mask; 389 retval = dma_set_coherent_mask(&dev->dev, DMA_BIT_MASK(32)); 390 if (retval) { 391 dev_err(&dev->dev, "can't set coherent DMA mask: %d\n", retval); 392 return retval; 393 } 394 395 res = platform_get_resource(dev, IORESOURCE_MEM, 0); 396 hsotg->regs = devm_ioremap_resource(&dev->dev, res); 397 if (IS_ERR(hsotg->regs)) 398 return PTR_ERR(hsotg->regs); 399 400 dev_dbg(&dev->dev, "mapped PA %08lx to VA %p\n", 401 (unsigned long)res->start, hsotg->regs); 402 403 retval = dwc2_lowlevel_hw_init(hsotg); 404 if (retval) 405 return retval; 406 407 spin_lock_init(&hsotg->lock); 408 409 hsotg->irq = platform_get_irq(dev, 0); 410 if (hsotg->irq < 0) 411 return hsotg->irq; 412 413 dev_dbg(hsotg->dev, "registering common handler for irq%d\n", 414 hsotg->irq); 415 retval = devm_request_irq(hsotg->dev, hsotg->irq, 416 dwc2_handle_common_intr, IRQF_SHARED, 417 dev_name(hsotg->dev), hsotg); 418 if (retval) 419 return retval; 420 421 hsotg->vbus_supply = devm_regulator_get_optional(hsotg->dev, "vbus"); 422 if (IS_ERR(hsotg->vbus_supply)) { 423 retval = PTR_ERR(hsotg->vbus_supply); 424 hsotg->vbus_supply = NULL; 425 if (retval != -ENODEV) 426 return retval; 427 } 428 429 retval = dwc2_lowlevel_hw_enable(hsotg); 430 if (retval) 431 return retval; 432 433 hsotg->needs_byte_swap = dwc2_check_core_endianness(hsotg); 434 435 retval = dwc2_get_dr_mode(hsotg); 436 if (retval) 437 goto error; 438 439 hsotg->need_phy_for_wake = 440 of_property_read_bool(dev->dev.of_node, 441 "snps,need-phy-for-wake"); 442 443 /* 444 * Reset before dwc2_get_hwparams() then it could get power-on real 445 * reset value form registers. 446 */ 447 retval = dwc2_core_reset(hsotg, false); 448 if (retval) 449 goto error; 450 451 /* Detect config values from hardware */ 452 retval = dwc2_get_hwparams(hsotg); 453 if (retval) 454 goto error; 455 456 /* 457 * For OTG cores, set the force mode bits to reflect the value 458 * of dr_mode. Force mode bits should not be touched at any 459 * other time after this. 460 */ 461 dwc2_force_dr_mode(hsotg); 462 463 retval = dwc2_init_params(hsotg); 464 if (retval) 465 goto error; 466 467 if (hsotg->dr_mode != USB_DR_MODE_HOST) { 468 retval = dwc2_gadget_init(hsotg); 469 if (retval) 470 goto error; 471 hsotg->gadget_enabled = 1; 472 } 473 474 /* 475 * If we need PHY for wakeup we must be wakeup capable. 476 * When we have a device that can wake without the PHY we 477 * can adjust this condition. 478 */ 479 if (hsotg->need_phy_for_wake) 480 device_set_wakeup_capable(&dev->dev, true); 481 482 hsotg->reset_phy_on_wake = 483 of_property_read_bool(dev->dev.of_node, 484 "snps,reset-phy-on-wake"); 485 if (hsotg->reset_phy_on_wake && !hsotg->phy) { 486 dev_warn(hsotg->dev, 487 "Quirk reset-phy-on-wake only supports generic PHYs\n"); 488 hsotg->reset_phy_on_wake = false; 489 } 490 491 if (hsotg->dr_mode != USB_DR_MODE_PERIPHERAL) { 492 retval = dwc2_hcd_init(hsotg); 493 if (retval) { 494 if (hsotg->gadget_enabled) 495 dwc2_hsotg_remove(hsotg); 496 goto error; 497 } 498 hsotg->hcd_enabled = 1; 499 } 500 501 platform_set_drvdata(dev, hsotg); 502 hsotg->hibernated = 0; 503 504 dwc2_debugfs_init(hsotg); 505 506 /* Gadget code manages lowlevel hw on its own */ 507 if (hsotg->dr_mode == USB_DR_MODE_PERIPHERAL) 508 dwc2_lowlevel_hw_disable(hsotg); 509 510 return 0; 511 512 error: 513 dwc2_lowlevel_hw_disable(hsotg); 514 return retval; 515 } 516 517 static int __maybe_unused dwc2_suspend(struct device *dev) 518 { 519 struct dwc2_hsotg *dwc2 = dev_get_drvdata(dev); 520 bool is_device_mode = dwc2_is_device_mode(dwc2); 521 int ret = 0; 522 523 if (is_device_mode) 524 dwc2_hsotg_suspend(dwc2); 525 526 if (dwc2->ll_hw_enabled && 527 (is_device_mode || dwc2_host_can_poweroff_phy(dwc2))) { 528 ret = __dwc2_lowlevel_hw_disable(dwc2); 529 dwc2->phy_off_for_suspend = true; 530 } 531 532 return ret; 533 } 534 535 static int __maybe_unused dwc2_resume(struct device *dev) 536 { 537 struct dwc2_hsotg *dwc2 = dev_get_drvdata(dev); 538 int ret = 0; 539 540 if (dwc2->phy_off_for_suspend && dwc2->ll_hw_enabled) { 541 ret = __dwc2_lowlevel_hw_enable(dwc2); 542 if (ret) 543 return ret; 544 } 545 dwc2->phy_off_for_suspend = false; 546 547 if (dwc2_is_device_mode(dwc2)) 548 ret = dwc2_hsotg_resume(dwc2); 549 550 return ret; 551 } 552 553 static const struct dev_pm_ops dwc2_dev_pm_ops = { 554 SET_SYSTEM_SLEEP_PM_OPS(dwc2_suspend, dwc2_resume) 555 }; 556 557 static struct platform_driver dwc2_platform_driver = { 558 .driver = { 559 .name = dwc2_driver_name, 560 .of_match_table = dwc2_of_match_table, 561 .pm = &dwc2_dev_pm_ops, 562 }, 563 .probe = dwc2_driver_probe, 564 .remove = dwc2_driver_remove, 565 .shutdown = dwc2_driver_shutdown, 566 }; 567 568 module_platform_driver(dwc2_platform_driver); 569 570 MODULE_DESCRIPTION("DESIGNWARE HS OTG Platform Glue"); 571 MODULE_AUTHOR("Matthijs Kooijman <matthijs@stdin.nl>"); 572 MODULE_LICENSE("Dual BSD/GPL"); 573