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 /* Set default UTMI width */ 225 hsotg->phyif = GUSBCFG_PHYIF16; 226 227 /* 228 * Attempt to find a generic PHY, then look for an old style 229 * USB PHY and then fall back to pdata 230 */ 231 hsotg->phy = devm_phy_get(hsotg->dev, "usb2-phy"); 232 if (IS_ERR(hsotg->phy)) { 233 ret = PTR_ERR(hsotg->phy); 234 switch (ret) { 235 case -ENODEV: 236 case -ENOSYS: 237 hsotg->phy = NULL; 238 break; 239 case -EPROBE_DEFER: 240 return ret; 241 default: 242 dev_err(hsotg->dev, "error getting phy %d\n", ret); 243 return ret; 244 } 245 } 246 247 if (!hsotg->phy) { 248 hsotg->uphy = devm_usb_get_phy(hsotg->dev, USB_PHY_TYPE_USB2); 249 if (IS_ERR(hsotg->uphy)) { 250 ret = PTR_ERR(hsotg->uphy); 251 switch (ret) { 252 case -ENODEV: 253 case -ENXIO: 254 hsotg->uphy = NULL; 255 break; 256 case -EPROBE_DEFER: 257 return ret; 258 default: 259 dev_err(hsotg->dev, "error getting usb phy %d\n", 260 ret); 261 return ret; 262 } 263 } 264 } 265 266 hsotg->plat = dev_get_platdata(hsotg->dev); 267 268 if (hsotg->phy) { 269 /* 270 * If using the generic PHY framework, check if the PHY bus 271 * width is 8-bit and set the phyif appropriately. 272 */ 273 if (phy_get_bus_width(hsotg->phy) == 8) 274 hsotg->phyif = GUSBCFG_PHYIF8; 275 } 276 277 /* Clock */ 278 hsotg->clk = devm_clk_get(hsotg->dev, "otg"); 279 if (IS_ERR(hsotg->clk)) { 280 hsotg->clk = NULL; 281 dev_dbg(hsotg->dev, "cannot get otg clock\n"); 282 } 283 284 /* Regulators */ 285 for (i = 0; i < ARRAY_SIZE(hsotg->supplies); i++) 286 hsotg->supplies[i].supply = dwc2_hsotg_supply_names[i]; 287 288 ret = devm_regulator_bulk_get(hsotg->dev, ARRAY_SIZE(hsotg->supplies), 289 hsotg->supplies); 290 if (ret) { 291 dev_err(hsotg->dev, "failed to request supplies: %d\n", ret); 292 return ret; 293 } 294 return 0; 295 } 296 297 /** 298 * dwc2_driver_remove() - Called when the DWC_otg core is unregistered with the 299 * DWC_otg driver 300 * 301 * @dev: Platform device 302 * 303 * This routine is called, for example, when the rmmod command is executed. The 304 * device may or may not be electrically present. If it is present, the driver 305 * stops device processing. Any resources used on behalf of this device are 306 * freed. 307 */ 308 static int dwc2_driver_remove(struct platform_device *dev) 309 { 310 struct dwc2_hsotg *hsotg = platform_get_drvdata(dev); 311 312 dwc2_debugfs_exit(hsotg); 313 if (hsotg->hcd_enabled) 314 dwc2_hcd_remove(hsotg); 315 if (hsotg->gadget_enabled) 316 dwc2_hsotg_remove(hsotg); 317 318 if (hsotg->ll_hw_enabled) 319 dwc2_lowlevel_hw_disable(hsotg); 320 321 reset_control_assert(hsotg->reset); 322 323 return 0; 324 } 325 326 /** 327 * dwc2_driver_shutdown() - Called on device shutdown 328 * 329 * @dev: Platform device 330 * 331 * In specific conditions (involving usb hubs) dwc2 devices can create a 332 * lot of interrupts, even to the point of overwhelming devices running 333 * at low frequencies. Some devices need to do special clock handling 334 * at shutdown-time which may bring the system clock below the threshold 335 * of being able to handle the dwc2 interrupts. Disabling dwc2-irqs 336 * prevents reboots/poweroffs from getting stuck in such cases. 337 */ 338 static void dwc2_driver_shutdown(struct platform_device *dev) 339 { 340 struct dwc2_hsotg *hsotg = platform_get_drvdata(dev); 341 342 disable_irq(hsotg->irq); 343 } 344 345 /** 346 * dwc2_driver_probe() - Called when the DWC_otg core is bound to the DWC_otg 347 * driver 348 * 349 * @dev: Platform device 350 * 351 * This routine creates the driver components required to control the device 352 * (core, HCD, and PCD) and initializes the device. The driver components are 353 * stored in a dwc2_hsotg structure. A reference to the dwc2_hsotg is saved 354 * in the device private data. This allows the driver to access the dwc2_hsotg 355 * structure on subsequent calls to driver methods for this device. 356 */ 357 static int dwc2_driver_probe(struct platform_device *dev) 358 { 359 struct dwc2_hsotg *hsotg; 360 struct resource *res; 361 int retval; 362 363 hsotg = devm_kzalloc(&dev->dev, sizeof(*hsotg), GFP_KERNEL); 364 if (!hsotg) 365 return -ENOMEM; 366 367 hsotg->dev = &dev->dev; 368 369 /* 370 * Use reasonable defaults so platforms don't have to provide these. 371 */ 372 if (!dev->dev.dma_mask) 373 dev->dev.dma_mask = &dev->dev.coherent_dma_mask; 374 retval = dma_set_coherent_mask(&dev->dev, DMA_BIT_MASK(32)); 375 if (retval) 376 return retval; 377 378 res = platform_get_resource(dev, IORESOURCE_MEM, 0); 379 hsotg->regs = devm_ioremap_resource(&dev->dev, res); 380 if (IS_ERR(hsotg->regs)) 381 return PTR_ERR(hsotg->regs); 382 383 dev_dbg(&dev->dev, "mapped PA %08lx to VA %p\n", 384 (unsigned long)res->start, hsotg->regs); 385 386 retval = dwc2_lowlevel_hw_init(hsotg); 387 if (retval) 388 return retval; 389 390 spin_lock_init(&hsotg->lock); 391 392 hsotg->irq = platform_get_irq(dev, 0); 393 if (hsotg->irq < 0) { 394 dev_err(&dev->dev, "missing IRQ resource\n"); 395 return hsotg->irq; 396 } 397 398 dev_dbg(hsotg->dev, "registering common handler for irq%d\n", 399 hsotg->irq); 400 retval = devm_request_irq(hsotg->dev, hsotg->irq, 401 dwc2_handle_common_intr, IRQF_SHARED, 402 dev_name(hsotg->dev), hsotg); 403 if (retval) 404 return retval; 405 406 retval = dwc2_lowlevel_hw_enable(hsotg); 407 if (retval) 408 return retval; 409 410 retval = dwc2_get_dr_mode(hsotg); 411 if (retval) 412 goto error; 413 414 /* 415 * Reset before dwc2_get_hwparams() then it could get power-on real 416 * reset value form registers. 417 */ 418 dwc2_core_reset_and_force_dr_mode(hsotg); 419 420 /* Detect config values from hardware */ 421 retval = dwc2_get_hwparams(hsotg); 422 if (retval) 423 goto error; 424 425 dwc2_force_dr_mode(hsotg); 426 427 retval = dwc2_init_params(hsotg); 428 if (retval) 429 goto error; 430 431 if (hsotg->dr_mode != USB_DR_MODE_HOST) { 432 retval = dwc2_gadget_init(hsotg, hsotg->irq); 433 if (retval) 434 goto error; 435 hsotg->gadget_enabled = 1; 436 } 437 438 if (hsotg->dr_mode != USB_DR_MODE_PERIPHERAL) { 439 retval = dwc2_hcd_init(hsotg); 440 if (retval) { 441 if (hsotg->gadget_enabled) 442 dwc2_hsotg_remove(hsotg); 443 goto error; 444 } 445 hsotg->hcd_enabled = 1; 446 } 447 448 platform_set_drvdata(dev, hsotg); 449 450 dwc2_debugfs_init(hsotg); 451 452 /* Gadget code manages lowlevel hw on its own */ 453 if (hsotg->dr_mode == USB_DR_MODE_PERIPHERAL) 454 dwc2_lowlevel_hw_disable(hsotg); 455 456 return 0; 457 458 error: 459 dwc2_lowlevel_hw_disable(hsotg); 460 return retval; 461 } 462 463 static int __maybe_unused dwc2_suspend(struct device *dev) 464 { 465 struct dwc2_hsotg *dwc2 = dev_get_drvdata(dev); 466 int ret = 0; 467 468 if (dwc2_is_device_mode(dwc2)) 469 dwc2_hsotg_suspend(dwc2); 470 471 if (dwc2->ll_hw_enabled) 472 ret = __dwc2_lowlevel_hw_disable(dwc2); 473 474 return ret; 475 } 476 477 static int __maybe_unused dwc2_resume(struct device *dev) 478 { 479 struct dwc2_hsotg *dwc2 = dev_get_drvdata(dev); 480 int ret = 0; 481 482 if (dwc2->ll_hw_enabled) { 483 ret = __dwc2_lowlevel_hw_enable(dwc2); 484 if (ret) 485 return ret; 486 } 487 488 if (dwc2_is_device_mode(dwc2)) 489 ret = dwc2_hsotg_resume(dwc2); 490 491 return ret; 492 } 493 494 static const struct dev_pm_ops dwc2_dev_pm_ops = { 495 SET_SYSTEM_SLEEP_PM_OPS(dwc2_suspend, dwc2_resume) 496 }; 497 498 static struct platform_driver dwc2_platform_driver = { 499 .driver = { 500 .name = dwc2_driver_name, 501 .of_match_table = dwc2_of_match_table, 502 .pm = &dwc2_dev_pm_ops, 503 }, 504 .probe = dwc2_driver_probe, 505 .remove = dwc2_driver_remove, 506 .shutdown = dwc2_driver_shutdown, 507 }; 508 509 module_platform_driver(dwc2_platform_driver); 510 511 MODULE_DESCRIPTION("DESIGNWARE HS OTG Platform Glue"); 512 MODULE_AUTHOR("Matthijs Kooijman <matthijs@stdin.nl>"); 513 MODULE_LICENSE("Dual BSD/GPL"); 514