Merge tag 'aspeed-5.5-devicetree-fixes' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-block.git] / drivers / usb / dwc3 / drd.c
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 - http://www.ti.com
6  *
7  * Authors: Roger Quadros <rogerq@ti.com>
8  */
9
10 #include <linux/extcon.h>
11 #include <linux/of_graph.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
19 static void dwc3_otg_disable_events(struct dwc3 *dwc, u32 disable_mask)
20 {
21         u32 reg = dwc3_readl(dwc->regs, DWC3_OEVTEN);
22
23         reg &= ~(disable_mask);
24         dwc3_writel(dwc->regs, DWC3_OEVTEN, reg);
25 }
26
27 static void dwc3_otg_enable_events(struct dwc3 *dwc, u32 enable_mask)
28 {
29         u32 reg = dwc3_readl(dwc->regs, DWC3_OEVTEN);
30
31         reg |= (enable_mask);
32         dwc3_writel(dwc->regs, DWC3_OEVTEN, reg);
33 }
34
35 static void dwc3_otg_clear_events(struct dwc3 *dwc)
36 {
37         u32 reg = dwc3_readl(dwc->regs, DWC3_OEVT);
38
39         dwc3_writel(dwc->regs, DWC3_OEVTEN, 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
52 static irqreturn_t dwc3_otg_thread_irq(int irq, void *_dwc)
53 {
54         struct dwc3 *dwc = _dwc;
55
56         spin_lock(&dwc->lock);
57         if (dwc->otg_restart_host) {
58                 dwc3_otg_host_init(dwc);
59                 dwc->otg_restart_host = 0;
60         }
61
62         spin_unlock(&dwc->lock);
63
64         dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_OTG);
65
66         return IRQ_HANDLED;
67 }
68
69 static 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(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(dwc->regs, DWC3_OEVT, 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 = 1;
86                 dwc3_writel(dwc->regs, DWC3_OEVT, reg);
87                 ret = IRQ_WAKE_THREAD;
88         }
89
90         return ret;
91 }
92
93 static 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(dwc->regs, DWC3_OCFG);
104         reg |= DWC3_OCFG_SFTRSTMASK;
105         dwc3_writel(dwc->regs, DWC3_OCFG, reg);
106
107         /* Disable hibernation for simplicity */
108         reg = dwc3_readl(dwc->regs, DWC3_GCTL);
109         reg &= ~DWC3_GCTL_GBLHIBERNATIONEN;
110         dwc3_writel(dwc->regs, DWC3_GCTL, 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(dwc->regs, DWC3_OCFG);
118         reg &= ~(DWC3_OCFG_SRPCAP | DWC3_OCFG_HNPCAP);
119         dwc3_writel(dwc->regs, DWC3_OCFG, 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(dwc->regs, DWC3_OCTL);
131         reg |= DWC3_OCTL_PERIMODE;
132         reg &= ~(DWC3_OCTL_DEVSETHNPEN | DWC3_OCTL_HSTSETHNPEN |
133                  DWC3_OCTL_HNPREQ);
134         dwc3_writel(dwc->regs, DWC3_OCTL, reg);
135 }
136
137 static 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(dwc3_pdev, "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(dwc3_pdev, "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
163 out:
164         return irq;
165 }
166
167 void 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(dwc->regs, DWC3_GUSB2PHYCFG(0));
179         reg &= ~DWC3_GUSB2PHYCFG_SUSPHY;
180         dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
181
182         /* Initialize OTG registers */
183         dwc3_otgregs_init(dwc);
184 }
185
186 void 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 */
195 void 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(dwc->regs, DWC3_OCTL);
207         reg &= ~(DWC3_OCTL_PERIMODE | DWC3_OCTL_TERMSELIDPULSE |
208                         DWC3_OCTL_DEVSETHNPEN | DWC3_OCTL_HSTSETHNPEN);
209         dwc3_writel(dwc->regs, DWC3_OCTL, reg);
210
211         /*
212          * OCFG.DisPrtPwrCutoff = 0/1
213          */
214         reg = dwc3_readl(dwc->regs, DWC3_OCFG);
215         reg &= ~DWC3_OCFG_DISPWRCUTTOFF;
216         dwc3_writel(dwc->regs, DWC3_OCFG, 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(dwc->regs, DWC3_GUSB2PHYCFG(0));
233                 reg |= DWC3_GUSB2PHYCFG_SUSPHY;
234                 dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
235         }
236
237         /* Set Port Power to enable VBUS: OCTL.PrtPwrCtl = 1 */
238         reg = dwc3_readl(dwc->regs, DWC3_OCTL);
239         reg |= DWC3_OCTL_PRTPWRCTL;
240         dwc3_writel(dwc->regs, DWC3_OCTL, reg);
241 }
242
243 /* should be called after Host controller driver is stopped */
244 static 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(dwc->regs, DWC3_OCTL);
262         reg &= ~(DWC3_OCTL_HSTSETHNPEN | DWC3_OCTL_PRTPWRCTL);
263         dwc3_writel(dwc->regs, DWC3_OCTL, reg);
264 }
265
266 /* should be called before the gadget controller driver is started */
267 static 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(dwc->regs, DWC3_OCFG);
278         /* OCFG.OTGSftRstMsk = 0/1 */
279         reg |= DWC3_OCFG_SFTRSTMASK;
280         dwc3_writel(dwc->regs, DWC3_OCFG, 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(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(dwc->regs, DWC3_OCTL, 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(dwc->regs, DWC3_GUSB2PHYCFG(0));
296                 reg |= DWC3_GUSB2PHYCFG_SUSPHY;
297                 dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
298         }
299         /* GCTL.GblHibernationEn = 0. Already 0. */
300 }
301
302 /* should be called after the gadget controller driver is stopped */
303 static 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(dwc->regs, DWC3_OCTL);
323         reg &= ~(DWC3_OCTL_DEVSETHNPEN | DWC3_OCTL_HNPREQ);
324         reg |= DWC3_OCTL_PERIMODE;
325         dwc3_writel(dwc->regs, DWC3_OCTL, reg);
326 }
327
328 void 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(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(&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(&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(&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(&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(dwc->usb2_phy->otg, 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(&dwc->lock, flags);
400
401                 if (dwc->usb2_phy)
402                         otg_set_vbus(dwc->usb2_phy->otg, 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
415 static void dwc3_drd_update(struct dwc3 *dwc)
416 {
417         int id;
418
419         if (dwc->edev) {
420                 id = extcon_get_state(dwc->edev, EXTCON_USB_HOST);
421                 if (id < 0)
422                         id = 0;
423                 dwc3_set_mode(dwc, id ?
424                               DWC3_GCTL_PRTCAP_HOST :
425                               DWC3_GCTL_PRTCAP_DEVICE);
426         }
427 }
428
429 static 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, event ?
435                       DWC3_GCTL_PRTCAP_HOST :
436                       DWC3_GCTL_PRTCAP_DEVICE);
437
438         return NOTIFY_DONE;
439 }
440
441 static struct extcon_dev *dwc3_get_extcon(struct dwc3 *dwc)
442 {
443         struct device *dev = dwc->dev;
444         struct device_node *np_phy, *np_conn;
445         struct extcon_dev *edev;
446         const char *name;
447
448         if (device_property_read_bool(dev, "extcon"))
449                 return extcon_get_edev_by_phandle(dev, 0);
450
451         /*
452          * Device tree platforms should get extcon via phandle.
453          * On ACPI platforms, we get the name from a device property.
454          * This device property is for kernel internal use only and
455          * is expected to be set by the glue code.
456          */
457         if (device_property_read_string(dev, "linux,extcon-name", &name) == 0) {
458                 edev = extcon_get_extcon_dev(name);
459                 if (!edev)
460                         return ERR_PTR(-EPROBE_DEFER);
461
462                 return edev;
463         }
464
465         np_phy = of_parse_phandle(dev->of_node, "phys", 0);
466         np_conn = of_graph_get_remote_node(np_phy, -1, -1);
467
468         if (np_conn)
469                 edev = extcon_find_edev_by_node(np_conn);
470         else
471                 edev = NULL;
472
473         of_node_put(np_conn);
474         of_node_put(np_phy);
475
476         return edev;
477 }
478
479 int dwc3_drd_init(struct dwc3 *dwc)
480 {
481         int ret, irq;
482
483         dwc->edev = dwc3_get_extcon(dwc);
484         if (IS_ERR(dwc->edev))
485                 return PTR_ERR(dwc->edev);
486
487         if (dwc->edev) {
488                 dwc->edev_nb.notifier_call = dwc3_drd_notifier;
489                 ret = extcon_register_notifier(dwc->edev, EXTCON_USB_HOST,
490                                                &dwc->edev_nb);
491                 if (ret < 0) {
492                         dev_err(dwc->dev, "couldn't register cable notifier\n");
493                         return ret;
494                 }
495
496                 dwc3_drd_update(dwc);
497         } else {
498                 dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_OTG);
499                 dwc->current_dr_role = DWC3_GCTL_PRTCAP_OTG;
500
501                 /* use OTG block to get ID event */
502                 irq = dwc3_otg_get_irq(dwc);
503                 if (irq < 0)
504                         return irq;
505
506                 dwc->otg_irq = irq;
507
508                 /* disable all OTG IRQs */
509                 dwc3_otg_disable_events(dwc, DWC3_OTG_ALL_EVENTS);
510                 /* clear all events */
511                 dwc3_otg_clear_events(dwc);
512
513                 ret = request_threaded_irq(dwc->otg_irq, dwc3_otg_irq,
514                                            dwc3_otg_thread_irq,
515                                            IRQF_SHARED, "dwc3-otg", dwc);
516                 if (ret) {
517                         dev_err(dwc->dev, "failed to request irq #%d --> %d\n",
518                                 dwc->otg_irq, ret);
519                         ret = -ENODEV;
520                         return ret;
521                 }
522
523                 dwc3_otg_init(dwc);
524                 dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_OTG);
525         }
526
527         return 0;
528 }
529
530 void dwc3_drd_exit(struct dwc3 *dwc)
531 {
532         unsigned long flags;
533
534         if (dwc->edev)
535                 extcon_unregister_notifier(dwc->edev, EXTCON_USB_HOST,
536                                            &dwc->edev_nb);
537
538         cancel_work_sync(&dwc->drd_work);
539
540         /* debug user might have changed role, clean based on current role */
541         switch (dwc->current_dr_role) {
542         case DWC3_GCTL_PRTCAP_HOST:
543                 dwc3_host_exit(dwc);
544                 break;
545         case DWC3_GCTL_PRTCAP_DEVICE:
546                 dwc3_gadget_exit(dwc);
547                 dwc3_event_buffers_cleanup(dwc);
548                 break;
549         case DWC3_GCTL_PRTCAP_OTG:
550                 dwc3_otg_exit(dwc);
551                 spin_lock_irqsave(&dwc->lock, flags);
552                 dwc->desired_otg_role = DWC3_OTG_ROLE_IDLE;
553                 spin_unlock_irqrestore(&dwc->lock, flags);
554                 dwc3_otg_update(dwc, 1);
555                 break;
556         default:
557                 break;
558         }
559
560         if (!dwc->edev)
561                 free_irq(dwc->otg_irq, dwc);
562 }