1// SPDX-License-Identifier: GPL-2.0
2/*
3 * drd.c - DesignWare USB3 DRD Controller Dual-role support
4 *
5 * Copyright (C) 2017 Texas Instruments Incorporated - https://www.ti.com
6 *
7 * Authors: Roger Quadros <rogerq@ti.com>
8 */
9
10#include <linux/extcon.h>
11#include <linux/of_platform.h>
12#include <linux/platform_device.h>
13#include <linux/property.h>
14
15#include "debug.h"
16#include "core.h"
17#include "gadget.h"
18
19static void dwc3_otg_disable_events(struct dwc3 *dwc, u32 disable_mask)
20{
21 u32 reg = dwc3_readl(base: dwc->regs, DWC3_OEVTEN);
22
23 reg &= ~(disable_mask);
24 dwc3_writel(base: dwc->regs, DWC3_OEVTEN, value: reg);
25}
26
27static void dwc3_otg_enable_events(struct dwc3 *dwc, u32 enable_mask)
28{
29 u32 reg = dwc3_readl(base: dwc->regs, DWC3_OEVTEN);
30
31 reg |= (enable_mask);
32 dwc3_writel(base: dwc->regs, DWC3_OEVTEN, value: reg);
33}
34
35static void dwc3_otg_clear_events(struct dwc3 *dwc)
36{
37 u32 reg = dwc3_readl(base: dwc->regs, DWC3_OEVT);
38
39 dwc3_writel(base: dwc->regs, DWC3_OEVTEN, value: reg);
40}
41
42#define DWC3_OTG_ALL_EVENTS (DWC3_OEVTEN_XHCIRUNSTPSETEN | \
43 DWC3_OEVTEN_DEVRUNSTPSETEN | DWC3_OEVTEN_HIBENTRYEN | \
44 DWC3_OEVTEN_CONIDSTSCHNGEN | DWC3_OEVTEN_HRRCONFNOTIFEN | \
45 DWC3_OEVTEN_HRRINITNOTIFEN | DWC3_OEVTEN_ADEVIDLEEN | \
46 DWC3_OEVTEN_ADEVBHOSTENDEN | DWC3_OEVTEN_ADEVHOSTEN | \
47 DWC3_OEVTEN_ADEVHNPCHNGEN | DWC3_OEVTEN_ADEVSRPDETEN | \
48 DWC3_OEVTEN_ADEVSESSENDDETEN | DWC3_OEVTEN_BDEVBHOSTENDEN | \
49 DWC3_OEVTEN_BDEVHNPCHNGEN | DWC3_OEVTEN_BDEVSESSVLDDETEN | \
50 DWC3_OEVTEN_BDEVVBUSCHNGEN)
51
52static irqreturn_t dwc3_otg_thread_irq(int irq, void *_dwc)
53{
54 struct dwc3 *dwc = _dwc;
55
56 spin_lock(lock: &dwc->lock);
57 if (dwc->otg_restart_host) {
58 dwc3_otg_host_init(dwc);
59 dwc->otg_restart_host = false;
60 }
61
62 spin_unlock(lock: &dwc->lock);
63
64 dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_OTG);
65
66 return IRQ_HANDLED;
67}
68
69static irqreturn_t dwc3_otg_irq(int irq, void *_dwc)
70{
71 u32 reg;
72 struct dwc3 *dwc = _dwc;
73 irqreturn_t ret = IRQ_NONE;
74
75 reg = dwc3_readl(base: dwc->regs, DWC3_OEVT);
76 if (reg) {
77 /* ignore non OTG events, we can't disable them in OEVTEN */
78 if (!(reg & DWC3_OTG_ALL_EVENTS)) {
79 dwc3_writel(base: dwc->regs, DWC3_OEVT, value: reg);
80 return IRQ_NONE;
81 }
82
83 if (dwc->current_otg_role == DWC3_OTG_ROLE_HOST &&
84 !(reg & DWC3_OEVT_DEVICEMODE))
85 dwc->otg_restart_host = true;
86 dwc3_writel(base: dwc->regs, DWC3_OEVT, value: reg);
87 ret = IRQ_WAKE_THREAD;
88 }
89
90 return ret;
91}
92
93static void dwc3_otgregs_init(struct dwc3 *dwc)
94{
95 u32 reg;
96
97 /*
98 * Prevent host/device reset from resetting OTG core.
99 * If we don't do this then xhci_reset (USBCMD.HCRST) will reset
100 * the signal outputs sent to the PHY, the OTG FSM logic of the
101 * core and also the resets to the VBUS filters inside the core.
102 */
103 reg = dwc3_readl(base: dwc->regs, DWC3_OCFG);
104 reg |= DWC3_OCFG_SFTRSTMASK;
105 dwc3_writel(base: dwc->regs, DWC3_OCFG, value: reg);
106
107 /* Disable hibernation for simplicity */
108 reg = dwc3_readl(base: dwc->regs, DWC3_GCTL);
109 reg &= ~DWC3_GCTL_GBLHIBERNATIONEN;
110 dwc3_writel(base: dwc->regs, DWC3_GCTL, value: reg);
111
112 /*
113 * Initialize OTG registers as per
114 * Figure 11-4 OTG Driver Overall Programming Flow
115 */
116 /* OCFG.SRPCap = 0, OCFG.HNPCap = 0 */
117 reg = dwc3_readl(base: dwc->regs, DWC3_OCFG);
118 reg &= ~(DWC3_OCFG_SRPCAP | DWC3_OCFG_HNPCAP);
119 dwc3_writel(base: dwc->regs, DWC3_OCFG, value: reg);
120 /* OEVT = FFFF */
121 dwc3_otg_clear_events(dwc);
122 /* OEVTEN = 0 */
123 dwc3_otg_disable_events(dwc, DWC3_OTG_ALL_EVENTS);
124 /* OEVTEN.ConIDStsChngEn = 1. Instead we enable all events */
125 dwc3_otg_enable_events(dwc, DWC3_OTG_ALL_EVENTS);
126 /*
127 * OCTL.PeriMode = 1, OCTL.DevSetHNPEn = 0, OCTL.HstSetHNPEn = 0,
128 * OCTL.HNPReq = 0
129 */
130 reg = dwc3_readl(base: dwc->regs, DWC3_OCTL);
131 reg |= DWC3_OCTL_PERIMODE;
132 reg &= ~(DWC3_OCTL_DEVSETHNPEN | DWC3_OCTL_HSTSETHNPEN |
133 DWC3_OCTL_HNPREQ);
134 dwc3_writel(base: dwc->regs, DWC3_OCTL, value: reg);
135}
136
137static int dwc3_otg_get_irq(struct dwc3 *dwc)
138{
139 struct platform_device *dwc3_pdev = to_platform_device(dwc->dev);
140 int irq;
141
142 irq = platform_get_irq_byname_optional(dev: dwc3_pdev, name: "otg");
143 if (irq > 0)
144 goto out;
145
146 if (irq == -EPROBE_DEFER)
147 goto out;
148
149 irq = platform_get_irq_byname_optional(dev: dwc3_pdev, name: "dwc_usb3");
150 if (irq > 0)
151 goto out;
152
153 if (irq == -EPROBE_DEFER)
154 goto out;
155
156 irq = platform_get_irq(dwc3_pdev, 0);
157 if (irq > 0)
158 goto out;
159
160 if (!irq)
161 irq = -EINVAL;
162
163out:
164 return irq;
165}
166
167void dwc3_otg_init(struct dwc3 *dwc)
168{
169 u32 reg;
170
171 /*
172 * As per Figure 11-4 OTG Driver Overall Programming Flow,
173 * block "Initialize GCTL for OTG operation".
174 */
175 /* GCTL.PrtCapDir=2'b11 */
176 dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_OTG);
177 /* GUSB2PHYCFG0.SusPHY=0 */
178 reg = dwc3_readl(base: dwc->regs, DWC3_GUSB2PHYCFG(0));
179 reg &= ~DWC3_GUSB2PHYCFG_SUSPHY;
180 dwc3_writel(base: dwc->regs, DWC3_GUSB2PHYCFG(0), value: reg);
181
182 /* Initialize OTG registers */
183 dwc3_otgregs_init(dwc);
184}
185
186void dwc3_otg_exit(struct dwc3 *dwc)
187{
188 /* disable all OTG IRQs */
189 dwc3_otg_disable_events(dwc, DWC3_OTG_ALL_EVENTS);
190 /* clear all events */
191 dwc3_otg_clear_events(dwc);
192}
193
194/* should be called before Host controller driver is started */
195void dwc3_otg_host_init(struct dwc3 *dwc)
196{
197 u32 reg;
198
199 /* As per Figure 11-10 A-Device Flow Diagram */
200 /* OCFG.HNPCap = 0, OCFG.SRPCap = 0. Already 0 */
201
202 /*
203 * OCTL.PeriMode=0, OCTL.TermSelDLPulse = 0,
204 * OCTL.DevSetHNPEn = 0, OCTL.HstSetHNPEn = 0
205 */
206 reg = dwc3_readl(base: dwc->regs, DWC3_OCTL);
207 reg &= ~(DWC3_OCTL_PERIMODE | DWC3_OCTL_TERMSELIDPULSE |
208 DWC3_OCTL_DEVSETHNPEN | DWC3_OCTL_HSTSETHNPEN);
209 dwc3_writel(base: dwc->regs, DWC3_OCTL, value: reg);
210
211 /*
212 * OCFG.DisPrtPwrCutoff = 0/1
213 */
214 reg = dwc3_readl(base: dwc->regs, DWC3_OCFG);
215 reg &= ~DWC3_OCFG_DISPWRCUTTOFF;
216 dwc3_writel(base: dwc->regs, DWC3_OCFG, value: reg);
217
218 /*
219 * OCFG.SRPCap = 1, OCFG.HNPCap = GHWPARAMS6.HNP_CAP
220 * We don't want SRP/HNP for simple dual-role so leave
221 * these disabled.
222 */
223
224 /*
225 * OEVTEN.OTGADevHostEvntEn = 1
226 * OEVTEN.OTGADevSessEndDetEvntEn = 1
227 * We don't want HNP/role-swap so leave these disabled.
228 */
229
230 /* GUSB2PHYCFG.ULPIAutoRes = 1/0, GUSB2PHYCFG.SusPHY = 1 */
231 if (!dwc->dis_u2_susphy_quirk) {
232 reg = dwc3_readl(base: dwc->regs, DWC3_GUSB2PHYCFG(0));
233 reg |= DWC3_GUSB2PHYCFG_SUSPHY;
234 dwc3_writel(base: dwc->regs, DWC3_GUSB2PHYCFG(0), value: reg);
235 }
236
237 /* Set Port Power to enable VBUS: OCTL.PrtPwrCtl = 1 */
238 reg = dwc3_readl(base: dwc->regs, DWC3_OCTL);
239 reg |= DWC3_OCTL_PRTPWRCTL;
240 dwc3_writel(base: dwc->regs, DWC3_OCTL, value: reg);
241}
242
243/* should be called after Host controller driver is stopped */
244static void dwc3_otg_host_exit(struct dwc3 *dwc)
245{
246 u32 reg;
247
248 /*
249 * Exit from A-device flow as per
250 * Figure 11-4 OTG Driver Overall Programming Flow
251 */
252
253 /*
254 * OEVTEN.OTGADevBHostEndEvntEn=0, OEVTEN.OTGADevHNPChngEvntEn=0
255 * OEVTEN.OTGADevSessEndDetEvntEn=0,
256 * OEVTEN.OTGADevHostEvntEn = 0
257 * But we don't disable any OTG events
258 */
259
260 /* OCTL.HstSetHNPEn = 0, OCTL.PrtPwrCtl=0 */
261 reg = dwc3_readl(base: dwc->regs, DWC3_OCTL);
262 reg &= ~(DWC3_OCTL_HSTSETHNPEN | DWC3_OCTL_PRTPWRCTL);
263 dwc3_writel(base: dwc->regs, DWC3_OCTL, value: reg);
264}
265
266/* should be called before the gadget controller driver is started */
267static void dwc3_otg_device_init(struct dwc3 *dwc)
268{
269 u32 reg;
270
271 /* As per Figure 11-20 B-Device Flow Diagram */
272
273 /*
274 * OCFG.HNPCap = GHWPARAMS6.HNP_CAP, OCFG.SRPCap = 1
275 * but we keep them 0 for simple dual-role operation.
276 */
277 reg = dwc3_readl(base: dwc->regs, DWC3_OCFG);
278 /* OCFG.OTGSftRstMsk = 0/1 */
279 reg |= DWC3_OCFG_SFTRSTMASK;
280 dwc3_writel(base: dwc->regs, DWC3_OCFG, value: reg);
281 /*
282 * OCTL.PeriMode = 1
283 * OCTL.TermSelDLPulse = 0/1, OCTL.HNPReq = 0
284 * OCTL.DevSetHNPEn = 0, OCTL.HstSetHNPEn = 0
285 */
286 reg = dwc3_readl(base: dwc->regs, DWC3_OCTL);
287 reg |= DWC3_OCTL_PERIMODE;
288 reg &= ~(DWC3_OCTL_TERMSELIDPULSE | DWC3_OCTL_HNPREQ |
289 DWC3_OCTL_DEVSETHNPEN | DWC3_OCTL_HSTSETHNPEN);
290 dwc3_writel(base: dwc->regs, DWC3_OCTL, value: reg);
291 /* OEVTEN.OTGBDevSesVldDetEvntEn = 1 */
292 dwc3_otg_enable_events(dwc, DWC3_OEVTEN_BDEVSESSVLDDETEN);
293 /* GUSB2PHYCFG.ULPIAutoRes = 0, GUSB2PHYCFG0.SusPHY = 1 */
294 if (!dwc->dis_u2_susphy_quirk) {
295 reg = dwc3_readl(base: dwc->regs, DWC3_GUSB2PHYCFG(0));
296 reg |= DWC3_GUSB2PHYCFG_SUSPHY;
297 dwc3_writel(base: dwc->regs, DWC3_GUSB2PHYCFG(0), value: reg);
298 }
299 /* GCTL.GblHibernationEn = 0. Already 0. */
300}
301
302/* should be called after the gadget controller driver is stopped */
303static void dwc3_otg_device_exit(struct dwc3 *dwc)
304{
305 u32 reg;
306
307 /*
308 * Exit from B-device flow as per
309 * Figure 11-4 OTG Driver Overall Programming Flow
310 */
311
312 /*
313 * OEVTEN.OTGBDevHNPChngEvntEn = 0
314 * OEVTEN.OTGBDevVBusChngEvntEn = 0
315 * OEVTEN.OTGBDevBHostEndEvntEn = 0
316 */
317 dwc3_otg_disable_events(dwc, DWC3_OEVTEN_BDEVHNPCHNGEN |
318 DWC3_OEVTEN_BDEVVBUSCHNGEN |
319 DWC3_OEVTEN_BDEVBHOSTENDEN);
320
321 /* OCTL.DevSetHNPEn = 0, OCTL.HNPReq = 0, OCTL.PeriMode=1 */
322 reg = dwc3_readl(base: dwc->regs, DWC3_OCTL);
323 reg &= ~(DWC3_OCTL_DEVSETHNPEN | DWC3_OCTL_HNPREQ);
324 reg |= DWC3_OCTL_PERIMODE;
325 dwc3_writel(base: dwc->regs, DWC3_OCTL, value: reg);
326}
327
328void dwc3_otg_update(struct dwc3 *dwc, bool ignore_idstatus)
329{
330 int ret;
331 u32 reg;
332 int id;
333 unsigned long flags;
334
335 if (dwc->dr_mode != USB_DR_MODE_OTG)
336 return;
337
338 /* don't do anything if debug user changed role to not OTG */
339 if (dwc->current_dr_role != DWC3_GCTL_PRTCAP_OTG)
340 return;
341
342 if (!ignore_idstatus) {
343 reg = dwc3_readl(base: dwc->regs, DWC3_OSTS);
344 id = !!(reg & DWC3_OSTS_CONIDSTS);
345
346 dwc->desired_otg_role = id ? DWC3_OTG_ROLE_DEVICE :
347 DWC3_OTG_ROLE_HOST;
348 }
349
350 if (dwc->desired_otg_role == dwc->current_otg_role)
351 return;
352
353 switch (dwc->current_otg_role) {
354 case DWC3_OTG_ROLE_HOST:
355 dwc3_host_exit(dwc);
356 spin_lock_irqsave(&dwc->lock, flags);
357 dwc3_otg_host_exit(dwc);
358 spin_unlock_irqrestore(lock: &dwc->lock, flags);
359 break;
360 case DWC3_OTG_ROLE_DEVICE:
361 dwc3_gadget_exit(dwc);
362 spin_lock_irqsave(&dwc->lock, flags);
363 dwc3_event_buffers_cleanup(dwc);
364 dwc3_otg_device_exit(dwc);
365 spin_unlock_irqrestore(lock: &dwc->lock, flags);
366 break;
367 default:
368 break;
369 }
370
371 spin_lock_irqsave(&dwc->lock, flags);
372
373 dwc->current_otg_role = dwc->desired_otg_role;
374
375 spin_unlock_irqrestore(lock: &dwc->lock, flags);
376
377 switch (dwc->desired_otg_role) {
378 case DWC3_OTG_ROLE_HOST:
379 spin_lock_irqsave(&dwc->lock, flags);
380 dwc3_otgregs_init(dwc);
381 dwc3_otg_host_init(dwc);
382 spin_unlock_irqrestore(lock: &dwc->lock, flags);
383 ret = dwc3_host_init(dwc);
384 if (ret) {
385 dev_err(dwc->dev, "failed to initialize host\n");
386 } else {
387 if (dwc->usb2_phy)
388 otg_set_vbus(otg: dwc->usb2_phy->otg, enabled: true);
389 if (dwc->usb2_generic_phy)
390 phy_set_mode(dwc->usb2_generic_phy,
391 PHY_MODE_USB_HOST);
392 }
393 break;
394 case DWC3_OTG_ROLE_DEVICE:
395 spin_lock_irqsave(&dwc->lock, flags);
396 dwc3_otgregs_init(dwc);
397 dwc3_otg_device_init(dwc);
398 dwc3_event_buffers_setup(dwc);
399 spin_unlock_irqrestore(lock: &dwc->lock, flags);
400
401 if (dwc->usb2_phy)
402 otg_set_vbus(otg: dwc->usb2_phy->otg, enabled: false);
403 if (dwc->usb2_generic_phy)
404 phy_set_mode(dwc->usb2_generic_phy,
405 PHY_MODE_USB_DEVICE);
406 ret = dwc3_gadget_init(dwc);
407 if (ret)
408 dev_err(dwc->dev, "failed to initialize peripheral\n");
409 break;
410 default:
411 break;
412 }
413}
414
415static void dwc3_drd_update(struct dwc3 *dwc)
416{
417 int id;
418
419 if (dwc->edev) {
420 id = extcon_get_state(edev: dwc->edev, EXTCON_USB_HOST);
421 if (id < 0)
422 id = 0;
423 dwc3_set_mode(dwc, mode: id ?
424 DWC3_GCTL_PRTCAP_HOST :
425 DWC3_GCTL_PRTCAP_DEVICE);
426 }
427}
428
429static int dwc3_drd_notifier(struct notifier_block *nb,
430 unsigned long event, void *ptr)
431{
432 struct dwc3 *dwc = container_of(nb, struct dwc3, edev_nb);
433
434 dwc3_set_mode(dwc, mode: event ?
435 DWC3_GCTL_PRTCAP_HOST :
436 DWC3_GCTL_PRTCAP_DEVICE);
437
438 return NOTIFY_DONE;
439}
440
441#if IS_ENABLED(CONFIG_USB_ROLE_SWITCH)
442#define ROLE_SWITCH 1
443static int dwc3_usb_role_switch_set(struct usb_role_switch *sw,
444 enum usb_role role)
445{
446 struct dwc3 *dwc = usb_role_switch_get_drvdata(sw);
447 u32 mode;
448
449 switch (role) {
450 case USB_ROLE_HOST:
451 mode = DWC3_GCTL_PRTCAP_HOST;
452 break;
453 case USB_ROLE_DEVICE:
454 mode = DWC3_GCTL_PRTCAP_DEVICE;
455 break;
456 default:
457 if (dwc->role_switch_default_mode == USB_DR_MODE_HOST)
458 mode = DWC3_GCTL_PRTCAP_HOST;
459 else
460 mode = DWC3_GCTL_PRTCAP_DEVICE;
461 break;
462 }
463
464 dwc3_set_mode(dwc, mode);
465 return 0;
466}
467
468static enum usb_role dwc3_usb_role_switch_get(struct usb_role_switch *sw)
469{
470 struct dwc3 *dwc = usb_role_switch_get_drvdata(sw);
471 unsigned long flags;
472 enum usb_role role;
473
474 spin_lock_irqsave(&dwc->lock, flags);
475 switch (dwc->current_dr_role) {
476 case DWC3_GCTL_PRTCAP_HOST:
477 role = USB_ROLE_HOST;
478 break;
479 case DWC3_GCTL_PRTCAP_DEVICE:
480 role = USB_ROLE_DEVICE;
481 break;
482 case DWC3_GCTL_PRTCAP_OTG:
483 role = dwc->current_otg_role;
484 break;
485 default:
486 if (dwc->role_switch_default_mode == USB_DR_MODE_HOST)
487 role = USB_ROLE_HOST;
488 else
489 role = USB_ROLE_DEVICE;
490 break;
491 }
492 spin_unlock_irqrestore(lock: &dwc->lock, flags);
493 return role;
494}
495
496static int dwc3_setup_role_switch(struct dwc3 *dwc)
497{
498 struct usb_role_switch_desc dwc3_role_switch = {NULL};
499 u32 mode;
500
501 dwc->role_switch_default_mode = usb_get_role_switch_default_mode(dev: dwc->dev);
502 if (dwc->role_switch_default_mode == USB_DR_MODE_HOST) {
503 mode = DWC3_GCTL_PRTCAP_HOST;
504 } else {
505 dwc->role_switch_default_mode = USB_DR_MODE_PERIPHERAL;
506 mode = DWC3_GCTL_PRTCAP_DEVICE;
507 }
508
509 dwc3_role_switch.fwnode = dev_fwnode(dwc->dev);
510 dwc3_role_switch.set = dwc3_usb_role_switch_set;
511 dwc3_role_switch.get = dwc3_usb_role_switch_get;
512 dwc3_role_switch.driver_data = dwc;
513 dwc->role_sw = usb_role_switch_register(parent: dwc->dev, desc: &dwc3_role_switch);
514 if (IS_ERR(ptr: dwc->role_sw))
515 return PTR_ERR(ptr: dwc->role_sw);
516
517 if (dwc->dev->of_node) {
518 /* populate connector entry */
519 int ret = devm_of_platform_populate(dev: dwc->dev);
520
521 if (ret) {
522 usb_role_switch_unregister(sw: dwc->role_sw);
523 dwc->role_sw = NULL;
524 dev_err(dwc->dev, "DWC3 platform devices creation failed: %i\n", ret);
525 return ret;
526 }
527 }
528
529 dwc3_set_mode(dwc, mode);
530 return 0;
531}
532#else
533#define ROLE_SWITCH 0
534#define dwc3_setup_role_switch(x) 0
535#endif
536
537int dwc3_drd_init(struct dwc3 *dwc)
538{
539 int ret, irq;
540
541 if (ROLE_SWITCH &&
542 device_property_read_bool(dev: dwc->dev, propname: "usb-role-switch"))
543 return dwc3_setup_role_switch(dwc);
544
545 if (dwc->edev) {
546 dwc->edev_nb.notifier_call = dwc3_drd_notifier;
547 ret = extcon_register_notifier(edev: dwc->edev, EXTCON_USB_HOST,
548 nb: &dwc->edev_nb);
549 if (ret < 0) {
550 dev_err(dwc->dev, "couldn't register cable notifier\n");
551 return ret;
552 }
553
554 dwc3_drd_update(dwc);
555 } else {
556 dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_OTG);
557
558 /* use OTG block to get ID event */
559 irq = dwc3_otg_get_irq(dwc);
560 if (irq < 0)
561 return irq;
562
563 dwc->otg_irq = irq;
564
565 /* disable all OTG IRQs */
566 dwc3_otg_disable_events(dwc, DWC3_OTG_ALL_EVENTS);
567 /* clear all events */
568 dwc3_otg_clear_events(dwc);
569
570 ret = request_threaded_irq(irq: dwc->otg_irq, handler: dwc3_otg_irq,
571 thread_fn: dwc3_otg_thread_irq,
572 IRQF_SHARED, name: "dwc3-otg", dev: dwc);
573 if (ret) {
574 dev_err(dwc->dev, "failed to request irq #%d --> %d\n",
575 dwc->otg_irq, ret);
576 ret = -ENODEV;
577 return ret;
578 }
579
580 dwc3_otg_init(dwc);
581 dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_OTG);
582 }
583
584 return 0;
585}
586
587void dwc3_drd_exit(struct dwc3 *dwc)
588{
589 unsigned long flags;
590
591 if (dwc->role_sw)
592 usb_role_switch_unregister(sw: dwc->role_sw);
593
594 if (dwc->edev)
595 extcon_unregister_notifier(edev: dwc->edev, EXTCON_USB_HOST,
596 nb: &dwc->edev_nb);
597
598 cancel_work_sync(work: &dwc->drd_work);
599
600 /* debug user might have changed role, clean based on current role */
601 switch (dwc->current_dr_role) {
602 case DWC3_GCTL_PRTCAP_HOST:
603 dwc3_host_exit(dwc);
604 break;
605 case DWC3_GCTL_PRTCAP_DEVICE:
606 dwc3_gadget_exit(dwc);
607 dwc3_event_buffers_cleanup(dwc);
608 break;
609 case DWC3_GCTL_PRTCAP_OTG:
610 dwc3_otg_exit(dwc);
611 spin_lock_irqsave(&dwc->lock, flags);
612 dwc->desired_otg_role = DWC3_OTG_ROLE_IDLE;
613 spin_unlock_irqrestore(lock: &dwc->lock, flags);
614 dwc3_otg_update(dwc, ignore_idstatus: 1);
615 break;
616 default:
617 break;
618 }
619
620 if (dwc->otg_irq)
621 free_irq(dwc->otg_irq, dwc);
622}
623

source code of linux/drivers/usb/dwc3/drd.c