UPSTREAM: usb: dwc3: gadget: Add the suspend state checking when stopping gadget
[firefly-linux-kernel-4.4.55.git] / drivers / usb / dwc3 / gadget.c
1 /**
2  * gadget.c - DesignWare USB3 DRD Controller Gadget Framework Link
3  *
4  * Copyright (C) 2010-2011 Texas Instruments Incorporated - http://www.ti.com
5  *
6  * Authors: Felipe Balbi <balbi@ti.com>,
7  *          Sebastian Andrzej Siewior <bigeasy@linutronix.de>
8  *
9  * This program is free software: you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2  of
11  * the License as published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  */
18
19 #include <linux/kernel.h>
20 #include <linux/delay.h>
21 #include <linux/slab.h>
22 #include <linux/spinlock.h>
23 #include <linux/platform_device.h>
24 #include <linux/pm_runtime.h>
25 #include <linux/interrupt.h>
26 #include <linux/io.h>
27 #include <linux/list.h>
28 #include <linux/dma-mapping.h>
29
30 #include <linux/usb/ch9.h>
31 #include <linux/usb/gadget.h>
32
33 #include "debug.h"
34 #include "core.h"
35 #include "gadget.h"
36 #include "io.h"
37
38 /**
39  * dwc3_gadget_set_test_mode - Enables USB2 Test Modes
40  * @dwc: pointer to our context structure
41  * @mode: the mode to set (J, K SE0 NAK, Force Enable)
42  *
43  * Caller should take care of locking. This function will
44  * return 0 on success or -EINVAL if wrong Test Selector
45  * is passed
46  */
47 int dwc3_gadget_set_test_mode(struct dwc3 *dwc, int mode)
48 {
49         u32             reg;
50
51         reg = dwc3_readl(dwc->regs, DWC3_DCTL);
52         reg &= ~DWC3_DCTL_TSTCTRL_MASK;
53
54         switch (mode) {
55         case TEST_J:
56         case TEST_K:
57         case TEST_SE0_NAK:
58         case TEST_PACKET:
59         case TEST_FORCE_EN:
60                 reg |= mode << 1;
61                 break;
62         default:
63                 return -EINVAL;
64         }
65
66         dwc3_writel(dwc->regs, DWC3_DCTL, reg);
67
68         return 0;
69 }
70
71 /**
72  * dwc3_gadget_get_link_state - Gets current state of USB Link
73  * @dwc: pointer to our context structure
74  *
75  * Caller should take care of locking. This function will
76  * return the link state on success (>= 0) or -ETIMEDOUT.
77  */
78 int dwc3_gadget_get_link_state(struct dwc3 *dwc)
79 {
80         u32             reg;
81
82         reg = dwc3_readl(dwc->regs, DWC3_DSTS);
83
84         return DWC3_DSTS_USBLNKST(reg);
85 }
86
87 /**
88  * dwc3_gadget_set_link_state - Sets USB Link to a particular State
89  * @dwc: pointer to our context structure
90  * @state: the state to put link into
91  *
92  * Caller should take care of locking. This function will
93  * return 0 on success or -ETIMEDOUT.
94  */
95 int dwc3_gadget_set_link_state(struct dwc3 *dwc, enum dwc3_link_state state)
96 {
97         int             retries = 10000;
98         u32             reg;
99
100         /*
101          * Wait until device controller is ready. Only applies to 1.94a and
102          * later RTL.
103          */
104         if (dwc->revision >= DWC3_REVISION_194A) {
105                 while (--retries) {
106                         reg = dwc3_readl(dwc->regs, DWC3_DSTS);
107                         if (reg & DWC3_DSTS_DCNRD)
108                                 udelay(5);
109                         else
110                                 break;
111                 }
112
113                 if (retries <= 0)
114                         return -ETIMEDOUT;
115         }
116
117         reg = dwc3_readl(dwc->regs, DWC3_DCTL);
118         reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
119
120         /* set requested state */
121         reg |= DWC3_DCTL_ULSTCHNGREQ(state);
122         dwc3_writel(dwc->regs, DWC3_DCTL, reg);
123
124         /*
125          * The following code is racy when called from dwc3_gadget_wakeup,
126          * and is not needed, at least on newer versions
127          */
128         if (dwc->revision >= DWC3_REVISION_194A)
129                 return 0;
130
131         /* wait for a change in DSTS */
132         retries = 10000;
133         while (--retries) {
134                 reg = dwc3_readl(dwc->regs, DWC3_DSTS);
135
136                 if (DWC3_DSTS_USBLNKST(reg) == state)
137                         return 0;
138
139                 udelay(5);
140         }
141
142         dwc3_trace(trace_dwc3_gadget,
143                         "link state change request timed out");
144
145         return -ETIMEDOUT;
146 }
147
148 /**
149  * dwc3_ep_inc_trb() - Increment a TRB index.
150  * @index - Pointer to the TRB index to increment.
151  *
152  * The index should never point to the link TRB. After incrementing,
153  * if it is point to the link TRB, wrap around to the beginning. The
154  * link TRB is always at the last TRB entry.
155  */
156 static void dwc3_ep_inc_trb(u8 *index)
157 {
158         (*index)++;
159         if (*index == (DWC3_TRB_NUM - 1))
160                 *index = 0;
161 }
162
163 static void dwc3_ep_inc_enq(struct dwc3_ep *dep)
164 {
165         dwc3_ep_inc_trb(&dep->trb_enqueue);
166 }
167
168 static void dwc3_ep_inc_deq(struct dwc3_ep *dep)
169 {
170         dwc3_ep_inc_trb(&dep->trb_dequeue);
171 }
172
173 void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
174                 int status)
175 {
176         struct dwc3                     *dwc = dep->dwc;
177         int                             i;
178
179         if (req->started) {
180                 i = 0;
181                 do {
182                         dwc3_ep_inc_deq(dep);
183                 } while(++i < req->request.num_mapped_sgs);
184                 req->started = false;
185         }
186         list_del(&req->list);
187         req->trb = NULL;
188
189         if (req->request.status == -EINPROGRESS)
190                 req->request.status = status;
191
192         if (dwc->ep0_bounced && dep->number == 0)
193                 dwc->ep0_bounced = false;
194         else
195                 usb_gadget_unmap_request(&dwc->gadget, &req->request,
196                                 req->direction);
197
198         trace_dwc3_gadget_giveback(req);
199
200         spin_unlock(&dwc->lock);
201         usb_gadget_giveback_request(&dep->endpoint, &req->request);
202         spin_lock(&dwc->lock);
203
204         if (dep->number > 1)
205                 pm_runtime_put(dwc->dev);
206 }
207
208 int dwc3_send_gadget_generic_command(struct dwc3 *dwc, unsigned cmd, u32 param)
209 {
210         u32             timeout = 500;
211         int             status = 0;
212         int             ret = 0;
213         u32             reg;
214
215         dwc3_writel(dwc->regs, DWC3_DGCMDPAR, param);
216         dwc3_writel(dwc->regs, DWC3_DGCMD, cmd | DWC3_DGCMD_CMDACT);
217
218         do {
219                 reg = dwc3_readl(dwc->regs, DWC3_DGCMD);
220                 if (!(reg & DWC3_DGCMD_CMDACT)) {
221                         status = DWC3_DGCMD_STATUS(reg);
222                         if (status)
223                                 ret = -EINVAL;
224                         break;
225                 }
226         } while (timeout--);
227
228         if (!timeout) {
229                 ret = -ETIMEDOUT;
230                 status = -ETIMEDOUT;
231         }
232
233         trace_dwc3_gadget_generic_cmd(cmd, param, status);
234
235         return ret;
236 }
237
238 static int __dwc3_gadget_wakeup(struct dwc3 *dwc);
239
240 int dwc3_send_gadget_ep_cmd(struct dwc3_ep *dep, unsigned cmd,
241                 struct dwc3_gadget_ep_cmd_params *params)
242 {
243         struct dwc3             *dwc = dep->dwc;
244         u32                     timeout = 500;
245         u32                     reg;
246
247         int                     cmd_status = 0;
248         int                     susphy = false;
249         int                     ret = -EINVAL;
250
251         /*
252          * Synopsys Databook 2.60a states, on section 6.3.2.5.[1-8], that if
253          * we're issuing an endpoint command, we must check if
254          * GUSB2PHYCFG.SUSPHY bit is set. If it is, then we need to clear it.
255          *
256          * We will also set SUSPHY bit to what it was before returning as stated
257          * by the same section on Synopsys databook.
258          */
259         if (dwc->gadget.speed <= USB_SPEED_HIGH) {
260                 reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
261                 if (unlikely(reg & DWC3_GUSB2PHYCFG_SUSPHY)) {
262                         susphy = true;
263                         reg &= ~DWC3_GUSB2PHYCFG_SUSPHY;
264                         dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
265                 }
266         }
267
268         if (cmd == DWC3_DEPCMD_STARTTRANSFER) {
269                 int             needs_wakeup;
270
271                 needs_wakeup = (dwc->link_state == DWC3_LINK_STATE_U1 ||
272                                 dwc->link_state == DWC3_LINK_STATE_U2 ||
273                                 dwc->link_state == DWC3_LINK_STATE_U3);
274
275                 if (unlikely(needs_wakeup)) {
276                         ret = __dwc3_gadget_wakeup(dwc);
277                         dev_WARN_ONCE(dwc->dev, ret, "wakeup failed --> %d\n",
278                                         ret);
279                 }
280         }
281
282         dwc3_writel(dep->regs, DWC3_DEPCMDPAR0, params->param0);
283         dwc3_writel(dep->regs, DWC3_DEPCMDPAR1, params->param1);
284         dwc3_writel(dep->regs, DWC3_DEPCMDPAR2, params->param2);
285
286         dwc3_writel(dep->regs, DWC3_DEPCMD, cmd | DWC3_DEPCMD_CMDACT);
287         do {
288                 reg = dwc3_readl(dep->regs, DWC3_DEPCMD);
289                 if (!(reg & DWC3_DEPCMD_CMDACT)) {
290                         cmd_status = DWC3_DEPCMD_STATUS(reg);
291
292                         switch (cmd_status) {
293                         case 0:
294                                 ret = 0;
295                                 break;
296                         case DEPEVT_TRANSFER_NO_RESOURCE:
297                                 ret = -EINVAL;
298                                 break;
299                         case DEPEVT_TRANSFER_BUS_EXPIRY:
300                                 /*
301                                  * SW issues START TRANSFER command to
302                                  * isochronous ep with future frame interval. If
303                                  * future interval time has already passed when
304                                  * core receives the command, it will respond
305                                  * with an error status of 'Bus Expiry'.
306                                  *
307                                  * Instead of always returning -EINVAL, let's
308                                  * give a hint to the gadget driver that this is
309                                  * the case by returning -EAGAIN.
310                                  */
311                                 ret = -EAGAIN;
312                                 break;
313                         default:
314                                 dev_WARN(dwc->dev, "UNKNOWN cmd status\n");
315                         }
316
317                         break;
318                 }
319         } while (--timeout);
320
321         if (timeout == 0) {
322                 ret = -ETIMEDOUT;
323                 cmd_status = -ETIMEDOUT;
324         }
325
326         trace_dwc3_gadget_ep_cmd(dep, cmd, params, cmd_status);
327
328         if (unlikely(susphy)) {
329                 reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
330                 reg |= DWC3_GUSB2PHYCFG_SUSPHY;
331                 dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
332         }
333
334         return ret;
335 }
336
337 static int dwc3_send_clear_stall_ep_cmd(struct dwc3_ep *dep)
338 {
339         struct dwc3 *dwc = dep->dwc;
340         struct dwc3_gadget_ep_cmd_params params;
341         u32 cmd = DWC3_DEPCMD_CLEARSTALL;
342
343         /*
344          * As of core revision 2.60a the recommended programming model
345          * is to set the ClearPendIN bit when issuing a Clear Stall EP
346          * command for IN endpoints. This is to prevent an issue where
347          * some (non-compliant) hosts may not send ACK TPs for pending
348          * IN transfers due to a mishandled error condition. Synopsys
349          * STAR 9000614252.
350          */
351         if (dep->direction && (dwc->revision >= DWC3_REVISION_260A))
352                 cmd |= DWC3_DEPCMD_CLEARPENDIN;
353
354         memset(&params, 0, sizeof(params));
355
356         return dwc3_send_gadget_ep_cmd(dep, cmd, &params);
357 }
358
359 static dma_addr_t dwc3_trb_dma_offset(struct dwc3_ep *dep,
360                 struct dwc3_trb *trb)
361 {
362         u32             offset = (char *) trb - (char *) dep->trb_pool;
363
364         return dep->trb_pool_dma + offset;
365 }
366
367 static int dwc3_alloc_trb_pool(struct dwc3_ep *dep)
368 {
369         struct dwc3             *dwc = dep->dwc;
370
371         if (dep->trb_pool)
372                 return 0;
373
374         dep->trb_pool = dma_alloc_coherent(dwc->dev,
375                         sizeof(struct dwc3_trb) * DWC3_TRB_NUM,
376                         &dep->trb_pool_dma, GFP_KERNEL);
377         if (!dep->trb_pool) {
378                 dev_err(dep->dwc->dev, "failed to allocate trb pool for %s\n",
379                                 dep->name);
380                 return -ENOMEM;
381         }
382
383         return 0;
384 }
385
386 static void dwc3_free_trb_pool(struct dwc3_ep *dep)
387 {
388         struct dwc3             *dwc = dep->dwc;
389
390         dma_free_coherent(dwc->dev, sizeof(struct dwc3_trb) * DWC3_TRB_NUM,
391                         dep->trb_pool, dep->trb_pool_dma);
392
393         dep->trb_pool = NULL;
394         dep->trb_pool_dma = 0;
395 }
396
397 static int dwc3_gadget_set_xfer_resource(struct dwc3 *dwc, struct dwc3_ep *dep);
398
399 /**
400  * dwc3_gadget_start_config - Configure EP resources
401  * @dwc: pointer to our controller context structure
402  * @dep: endpoint that is being enabled
403  *
404  * The assignment of transfer resources cannot perfectly follow the
405  * data book due to the fact that the controller driver does not have
406  * all knowledge of the configuration in advance. It is given this
407  * information piecemeal by the composite gadget framework after every
408  * SET_CONFIGURATION and SET_INTERFACE. Trying to follow the databook
409  * programming model in this scenario can cause errors. For two
410  * reasons:
411  *
412  * 1) The databook says to do DEPSTARTCFG for every SET_CONFIGURATION
413  * and SET_INTERFACE (8.1.5). This is incorrect in the scenario of
414  * multiple interfaces.
415  *
416  * 2) The databook does not mention doing more DEPXFERCFG for new
417  * endpoint on alt setting (8.1.6).
418  *
419  * The following simplified method is used instead:
420  *
421  * All hardware endpoints can be assigned a transfer resource and this
422  * setting will stay persistent until either a core reset or
423  * hibernation. So whenever we do a DEPSTARTCFG(0) we can go ahead and
424  * do DEPXFERCFG for every hardware endpoint as well. We are
425  * guaranteed that there are as many transfer resources as endpoints.
426  *
427  * This function is called for each endpoint when it is being enabled
428  * but is triggered only when called for EP0-out, which always happens
429  * first, and which should only happen in one of the above conditions.
430  */
431 static int dwc3_gadget_start_config(struct dwc3 *dwc, struct dwc3_ep *dep)
432 {
433         struct dwc3_gadget_ep_cmd_params params;
434         u32                     cmd;
435         int                     i;
436         int                     ret;
437
438         if (dep->number)
439                 return 0;
440
441         memset(&params, 0x00, sizeof(params));
442         cmd = DWC3_DEPCMD_DEPSTARTCFG;
443
444         ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
445         if (ret)
446                 return ret;
447
448         for (i = 0; i < DWC3_ENDPOINTS_NUM; i++) {
449                 struct dwc3_ep *dep = dwc->eps[i];
450
451                 if (!dep)
452                         continue;
453
454                 ret = dwc3_gadget_set_xfer_resource(dwc, dep);
455                 if (ret)
456                         return ret;
457         }
458
459         return 0;
460 }
461
462 static int dwc3_gadget_set_ep_config(struct dwc3 *dwc, struct dwc3_ep *dep,
463                 const struct usb_endpoint_descriptor *desc,
464                 const struct usb_ss_ep_comp_descriptor *comp_desc,
465                 bool modify, bool restore)
466 {
467         struct dwc3_gadget_ep_cmd_params params;
468
469         if (dev_WARN_ONCE(dwc->dev, modify && restore,
470                                         "Can't modify and restore\n"))
471                 return -EINVAL;
472
473         memset(&params, 0x00, sizeof(params));
474
475         params.param0 = DWC3_DEPCFG_EP_TYPE(usb_endpoint_type(desc))
476                 | DWC3_DEPCFG_MAX_PACKET_SIZE(usb_endpoint_maxp(desc));
477
478         /* Burst size is only needed in SuperSpeed mode */
479         if (dwc->gadget.speed >= USB_SPEED_SUPER) {
480                 u32 burst = dep->endpoint.maxburst;
481                 params.param0 |= DWC3_DEPCFG_BURST_SIZE(burst - 1);
482         }
483
484         if (modify) {
485                 params.param0 |= DWC3_DEPCFG_ACTION_MODIFY;
486         } else if (restore) {
487                 params.param0 |= DWC3_DEPCFG_ACTION_RESTORE;
488                 params.param2 |= dep->saved_state;
489         } else {
490                 params.param0 |= DWC3_DEPCFG_ACTION_INIT;
491         }
492
493         params.param1 = DWC3_DEPCFG_XFER_COMPLETE_EN;
494
495         if (dep->number <= 1 || usb_endpoint_xfer_isoc(desc))
496                 params.param1 |= DWC3_DEPCFG_XFER_NOT_READY_EN;
497
498         if (usb_ss_max_streams(comp_desc) && usb_endpoint_xfer_bulk(desc)) {
499                 params.param1 |= DWC3_DEPCFG_STREAM_CAPABLE
500                         | DWC3_DEPCFG_STREAM_EVENT_EN;
501                 dep->stream_capable = true;
502         }
503
504         if (!usb_endpoint_xfer_control(desc))
505                 params.param1 |= DWC3_DEPCFG_XFER_IN_PROGRESS_EN;
506
507         /*
508          * We are doing 1:1 mapping for endpoints, meaning
509          * Physical Endpoints 2 maps to Logical Endpoint 2 and
510          * so on. We consider the direction bit as part of the physical
511          * endpoint number. So USB endpoint 0x81 is 0x03.
512          */
513         params.param1 |= DWC3_DEPCFG_EP_NUMBER(dep->number);
514
515         /*
516          * We must use the lower 16 TX FIFOs even though
517          * HW might have more
518          */
519         if (dep->direction)
520                 params.param0 |= DWC3_DEPCFG_FIFO_NUMBER(dep->number >> 1);
521
522         if (desc->bInterval) {
523                 params.param1 |= DWC3_DEPCFG_BINTERVAL_M1(desc->bInterval - 1);
524                 dep->interval = 1 << (desc->bInterval - 1);
525         }
526
527         return dwc3_send_gadget_ep_cmd(dep, DWC3_DEPCMD_SETEPCONFIG, &params);
528 }
529
530 static int dwc3_gadget_set_xfer_resource(struct dwc3 *dwc, struct dwc3_ep *dep)
531 {
532         struct dwc3_gadget_ep_cmd_params params;
533
534         memset(&params, 0x00, sizeof(params));
535
536         params.param0 = DWC3_DEPXFERCFG_NUM_XFER_RES(1);
537
538         return dwc3_send_gadget_ep_cmd(dep, DWC3_DEPCMD_SETTRANSFRESOURCE,
539                         &params);
540 }
541
542 /**
543  * __dwc3_gadget_ep_enable - Initializes a HW endpoint
544  * @dep: endpoint to be initialized
545  * @desc: USB Endpoint Descriptor
546  *
547  * Caller should take care of locking
548  */
549 static int __dwc3_gadget_ep_enable(struct dwc3_ep *dep,
550                 const struct usb_endpoint_descriptor *desc,
551                 const struct usb_ss_ep_comp_descriptor *comp_desc,
552                 bool modify, bool restore)
553 {
554         struct dwc3             *dwc = dep->dwc;
555         u32                     reg;
556         int                     ret;
557
558         dwc3_trace(trace_dwc3_gadget, "Enabling %s", dep->name);
559
560         if (!(dep->flags & DWC3_EP_ENABLED)) {
561                 ret = dwc3_gadget_start_config(dwc, dep);
562                 if (ret)
563                         return ret;
564         }
565
566         ret = dwc3_gadget_set_ep_config(dwc, dep, desc, comp_desc, modify,
567                         restore);
568         if (ret)
569                 return ret;
570
571         if (!(dep->flags & DWC3_EP_ENABLED)) {
572                 struct dwc3_trb *trb_st_hw;
573                 struct dwc3_trb *trb_link;
574
575                 dep->endpoint.desc = desc;
576                 dep->comp_desc = comp_desc;
577                 dep->type = usb_endpoint_type(desc);
578                 dep->flags |= DWC3_EP_ENABLED;
579
580                 reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);
581                 reg |= DWC3_DALEPENA_EP(dep->number);
582                 dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);
583
584                 if (usb_endpoint_xfer_control(desc))
585                         return 0;
586
587                 /* Initialize the TRB ring */
588                 dep->trb_dequeue = 0;
589                 dep->trb_enqueue = 0;
590                 memset(dep->trb_pool, 0,
591                        sizeof(struct dwc3_trb) * DWC3_TRB_NUM);
592
593                 /* Link TRB. The HWO bit is never reset */
594                 trb_st_hw = &dep->trb_pool[0];
595
596                 trb_link = &dep->trb_pool[DWC3_TRB_NUM - 1];
597                 trb_link->bpl = lower_32_bits(dwc3_trb_dma_offset(dep, trb_st_hw));
598                 trb_link->bph = upper_32_bits(dwc3_trb_dma_offset(dep, trb_st_hw));
599                 trb_link->ctrl |= DWC3_TRBCTL_LINK_TRB;
600                 trb_link->ctrl |= DWC3_TRB_CTRL_HWO;
601         }
602
603         return 0;
604 }
605
606 static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum, bool force);
607 static void dwc3_remove_requests(struct dwc3 *dwc, struct dwc3_ep *dep)
608 {
609         struct dwc3_request             *req;
610
611         dwc3_stop_active_transfer(dwc, dep->number, true);
612
613         /* - giveback all requests to gadget driver */
614         while (!list_empty(&dep->started_list)) {
615                 req = next_request(&dep->started_list);
616
617                 dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
618         }
619
620         while (!list_empty(&dep->pending_list)) {
621                 req = next_request(&dep->pending_list);
622
623                 dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
624         }
625 }
626
627 /**
628  * __dwc3_gadget_ep_disable - Disables a HW endpoint
629  * @dep: the endpoint to disable
630  *
631  * This function also removes requests which are currently processed ny the
632  * hardware and those which are not yet scheduled.
633  * Caller should take care of locking.
634  */
635 static int __dwc3_gadget_ep_disable(struct dwc3_ep *dep)
636 {
637         struct dwc3             *dwc = dep->dwc;
638         u32                     reg;
639
640         dwc3_trace(trace_dwc3_gadget, "Disabling %s", dep->name);
641
642         dwc3_remove_requests(dwc, dep);
643
644         /* make sure HW endpoint isn't stalled */
645         if (dep->flags & DWC3_EP_STALL)
646                 __dwc3_gadget_ep_set_halt(dep, 0, false);
647
648         reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);
649         reg &= ~DWC3_DALEPENA_EP(dep->number);
650         dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);
651
652         dep->stream_capable = false;
653         dep->endpoint.desc = NULL;
654         dep->comp_desc = NULL;
655         dep->type = 0;
656         dep->flags = 0;
657
658         return 0;
659 }
660
661 /* -------------------------------------------------------------------------- */
662
663 static int dwc3_gadget_ep0_enable(struct usb_ep *ep,
664                 const struct usb_endpoint_descriptor *desc)
665 {
666         return -EINVAL;
667 }
668
669 static int dwc3_gadget_ep0_disable(struct usb_ep *ep)
670 {
671         return -EINVAL;
672 }
673
674 /* -------------------------------------------------------------------------- */
675
676 static int dwc3_gadget_ep_enable(struct usb_ep *ep,
677                 const struct usb_endpoint_descriptor *desc)
678 {
679         struct dwc3_ep                  *dep;
680         struct dwc3                     *dwc;
681         unsigned long                   flags;
682         int                             ret;
683
684         if (!ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
685                 pr_debug("dwc3: invalid parameters\n");
686                 return -EINVAL;
687         }
688
689         if (!desc->wMaxPacketSize) {
690                 pr_debug("dwc3: missing wMaxPacketSize\n");
691                 return -EINVAL;
692         }
693
694         dep = to_dwc3_ep(ep);
695         dwc = dep->dwc;
696
697         if (dev_WARN_ONCE(dwc->dev, dep->flags & DWC3_EP_ENABLED,
698                                         "%s is already enabled\n",
699                                         dep->name))
700                 return 0;
701
702         spin_lock_irqsave(&dwc->lock, flags);
703         ret = __dwc3_gadget_ep_enable(dep, desc, ep->comp_desc, false, false);
704         spin_unlock_irqrestore(&dwc->lock, flags);
705
706         return ret;
707 }
708
709 static int dwc3_gadget_ep_disable(struct usb_ep *ep)
710 {
711         struct dwc3_ep                  *dep;
712         struct dwc3                     *dwc;
713         unsigned long                   flags;
714         int                             ret;
715
716         if (!ep) {
717                 pr_debug("dwc3: invalid parameters\n");
718                 return -EINVAL;
719         }
720
721         dep = to_dwc3_ep(ep);
722         dwc = dep->dwc;
723
724         if (dev_WARN_ONCE(dwc->dev, !(dep->flags & DWC3_EP_ENABLED),
725                                         "%s is already disabled\n",
726                                         dep->name))
727                 return 0;
728
729         spin_lock_irqsave(&dwc->lock, flags);
730         ret = __dwc3_gadget_ep_disable(dep);
731         spin_unlock_irqrestore(&dwc->lock, flags);
732
733         return ret;
734 }
735
736 static struct usb_request *dwc3_gadget_ep_alloc_request(struct usb_ep *ep,
737         gfp_t gfp_flags)
738 {
739         struct dwc3_request             *req;
740         struct dwc3_ep                  *dep = to_dwc3_ep(ep);
741
742         req = kzalloc(sizeof(*req), gfp_flags);
743         if (!req)
744                 return NULL;
745
746         req->epnum      = dep->number;
747         req->dep        = dep;
748
749         dep->allocated_requests++;
750
751         trace_dwc3_alloc_request(req);
752
753         return &req->request;
754 }
755
756 static void dwc3_gadget_ep_free_request(struct usb_ep *ep,
757                 struct usb_request *request)
758 {
759         struct dwc3_request             *req = to_dwc3_request(request);
760         struct dwc3_ep                  *dep = to_dwc3_ep(ep);
761
762         dep->allocated_requests--;
763         trace_dwc3_free_request(req);
764         kfree(req);
765 }
766
767 /**
768  * dwc3_prepare_one_trb - setup one TRB from one request
769  * @dep: endpoint for which this request is prepared
770  * @req: dwc3_request pointer
771  */
772 static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
773                 struct dwc3_request *req, dma_addr_t dma,
774                 unsigned length, unsigned last, unsigned chain, unsigned node)
775 {
776         struct dwc3_trb         *trb;
777
778         dwc3_trace(trace_dwc3_gadget, "%s: req %p dma %08llx length %d%s%s",
779                         dep->name, req, (unsigned long long) dma,
780                         length, last ? " last" : "",
781                         chain ? " chain" : "");
782
783
784         trb = &dep->trb_pool[dep->trb_enqueue];
785
786         if (!req->trb) {
787                 dwc3_gadget_move_started_request(req);
788                 req->trb = trb;
789                 req->trb_dma = dwc3_trb_dma_offset(dep, trb);
790                 req->first_trb_index = dep->trb_enqueue;
791         }
792
793         dwc3_ep_inc_enq(dep);
794
795         trb->size = DWC3_TRB_SIZE_LENGTH(length);
796         trb->bpl = lower_32_bits(dma);
797         trb->bph = upper_32_bits(dma);
798
799         switch (usb_endpoint_type(dep->endpoint.desc)) {
800         case USB_ENDPOINT_XFER_CONTROL:
801                 trb->ctrl = DWC3_TRBCTL_CONTROL_SETUP;
802                 break;
803
804         case USB_ENDPOINT_XFER_ISOC:
805                 if (!node)
806                         trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS_FIRST;
807                 else
808                         trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS;
809
810                 /* always enable Interrupt on Missed ISOC */
811                 trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
812                 break;
813
814         case USB_ENDPOINT_XFER_BULK:
815         case USB_ENDPOINT_XFER_INT:
816                 trb->ctrl = DWC3_TRBCTL_NORMAL;
817                 break;
818         default:
819                 /*
820                  * This is only possible with faulty memory because we
821                  * checked it already :)
822                  */
823                 BUG();
824         }
825
826         /* always enable Continue on Short Packet */
827         trb->ctrl |= DWC3_TRB_CTRL_CSP;
828
829         if (!req->request.no_interrupt && !chain)
830                 trb->ctrl |= DWC3_TRB_CTRL_IOC | DWC3_TRB_CTRL_ISP_IMI;
831
832         if (last)
833                 trb->ctrl |= DWC3_TRB_CTRL_LST;
834
835         if (chain)
836                 trb->ctrl |= DWC3_TRB_CTRL_CHN;
837
838         if (usb_endpoint_xfer_bulk(dep->endpoint.desc) && dep->stream_capable)
839                 trb->ctrl |= DWC3_TRB_CTRL_SID_SOFN(req->request.stream_id);
840
841         trb->ctrl |= DWC3_TRB_CTRL_HWO;
842
843         dep->queued_requests++;
844
845         trace_dwc3_prepare_trb(dep, trb);
846 }
847
848 /**
849  * dwc3_ep_prev_trb() - Returns the previous TRB in the ring
850  * @dep: The endpoint with the TRB ring
851  * @index: The index of the current TRB in the ring
852  *
853  * Returns the TRB prior to the one pointed to by the index. If the
854  * index is 0, we will wrap backwards, skip the link TRB, and return
855  * the one just before that.
856  */
857 static struct dwc3_trb *dwc3_ep_prev_trb(struct dwc3_ep *dep, u8 index)
858 {
859         if (!index)
860                 index = DWC3_TRB_NUM - 2;
861         else
862                 index = dep->trb_enqueue - 1;
863
864         return &dep->trb_pool[index];
865 }
866
867 static u32 dwc3_calc_trbs_left(struct dwc3_ep *dep)
868 {
869         struct dwc3_trb         *tmp;
870         u8                      trbs_left;
871
872         /*
873          * If enqueue & dequeue are equal than it is either full or empty.
874          *
875          * One way to know for sure is if the TRB right before us has HWO bit
876          * set or not. If it has, then we're definitely full and can't fit any
877          * more transfers in our ring.
878          */
879         if (dep->trb_enqueue == dep->trb_dequeue) {
880                 tmp = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
881                 if (tmp->ctrl & DWC3_TRB_CTRL_HWO)
882                         return 0;
883
884                 return DWC3_TRB_NUM - 1;
885         }
886
887         trbs_left = dep->trb_dequeue - dep->trb_enqueue;
888         trbs_left &= (DWC3_TRB_NUM - 1);
889
890         if (dep->trb_dequeue < dep->trb_enqueue)
891                 trbs_left--;
892
893         return trbs_left;
894 }
895
896 static void dwc3_prepare_one_trb_sg(struct dwc3_ep *dep,
897                 struct dwc3_request *req, unsigned int trbs_left,
898                 unsigned int more_coming)
899 {
900         struct usb_request *request = &req->request;
901         struct scatterlist *sg = request->sg;
902         struct scatterlist *s;
903         unsigned int    last = false;
904         unsigned int    length;
905         dma_addr_t      dma;
906         int             i;
907
908         for_each_sg(sg, s, request->num_mapped_sgs, i) {
909                 unsigned chain = true;
910
911                 length = sg_dma_len(s);
912                 dma = sg_dma_address(s);
913
914                 if (sg_is_last(s)) {
915                         if (usb_endpoint_xfer_int(dep->endpoint.desc) ||
916                                 !more_coming)
917                                 last = true;
918
919                         chain = false;
920                 }
921
922                 if (!trbs_left--)
923                         last = true;
924
925                 if (last)
926                         chain = false;
927
928                 dwc3_prepare_one_trb(dep, req, dma, length,
929                                 last, chain, i);
930
931                 if (last)
932                         break;
933         }
934 }
935
936 static void dwc3_prepare_one_trb_linear(struct dwc3_ep *dep,
937                 struct dwc3_request *req, unsigned int trbs_left,
938                 unsigned int more_coming)
939 {
940         unsigned int    last = false;
941         unsigned int    length;
942         dma_addr_t      dma;
943
944         dma = req->request.dma;
945         length = req->request.length;
946
947         if (!trbs_left)
948                 last = true;
949
950         /* Is this the last request? */
951         if (usb_endpoint_xfer_int(dep->endpoint.desc) || !more_coming)
952                 last = true;
953
954         dwc3_prepare_one_trb(dep, req, dma, length,
955                         last, false, 0);
956 }
957
958 /*
959  * dwc3_prepare_trbs - setup TRBs from requests
960  * @dep: endpoint for which requests are being prepared
961  *
962  * The function goes through the requests list and sets up TRBs for the
963  * transfers. The function returns once there are no more TRBs available or
964  * it runs out of requests.
965  */
966 static void dwc3_prepare_trbs(struct dwc3_ep *dep)
967 {
968         struct dwc3_request     *req, *n;
969         unsigned int            more_coming;
970         u32                     trbs_left;
971
972         BUILD_BUG_ON_NOT_POWER_OF_2(DWC3_TRB_NUM);
973
974         trbs_left = dwc3_calc_trbs_left(dep);
975         if (!trbs_left)
976                 return;
977
978         more_coming = dep->allocated_requests - dep->queued_requests;
979
980         list_for_each_entry_safe(req, n, &dep->pending_list, list) {
981                 if (req->request.num_mapped_sgs > 0)
982                         dwc3_prepare_one_trb_sg(dep, req, trbs_left--,
983                                         more_coming);
984                 else
985                         dwc3_prepare_one_trb_linear(dep, req, trbs_left--,
986                                         more_coming);
987
988                 if (!trbs_left)
989                         return;
990         }
991 }
992
993 static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep, u16 cmd_param)
994 {
995         struct dwc3_gadget_ep_cmd_params params;
996         struct dwc3_request             *req;
997         struct dwc3                     *dwc = dep->dwc;
998         int                             starting;
999         int                             ret;
1000         u32                             cmd;
1001
1002         starting = !(dep->flags & DWC3_EP_BUSY);
1003
1004         dwc3_prepare_trbs(dep);
1005         req = next_request(&dep->started_list);
1006         if (!req) {
1007                 dep->flags |= DWC3_EP_PENDING_REQUEST;
1008                 return 0;
1009         }
1010
1011         memset(&params, 0, sizeof(params));
1012
1013         if (starting) {
1014                 params.param0 = upper_32_bits(req->trb_dma);
1015                 params.param1 = lower_32_bits(req->trb_dma);
1016                 cmd = DWC3_DEPCMD_STARTTRANSFER |
1017                         DWC3_DEPCMD_PARAM(cmd_param);
1018         } else {
1019                 cmd = DWC3_DEPCMD_UPDATETRANSFER |
1020                         DWC3_DEPCMD_PARAM(dep->resource_index);
1021         }
1022
1023         ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
1024         if (ret < 0) {
1025                 /*
1026                  * FIXME we need to iterate over the list of requests
1027                  * here and stop, unmap, free and del each of the linked
1028                  * requests instead of what we do now.
1029                  */
1030                 usb_gadget_unmap_request(&dwc->gadget, &req->request,
1031                                 req->direction);
1032                 list_del(&req->list);
1033                 return ret;
1034         }
1035
1036         dep->flags |= DWC3_EP_BUSY;
1037
1038         if (starting) {
1039                 dep->resource_index = dwc3_gadget_ep_get_transfer_index(dep);
1040                 WARN_ON_ONCE(!dep->resource_index);
1041         }
1042
1043         return 0;
1044 }
1045
1046 static void __dwc3_gadget_start_isoc(struct dwc3 *dwc,
1047                 struct dwc3_ep *dep, u32 cur_uf)
1048 {
1049         u32 uf;
1050
1051         if (list_empty(&dep->pending_list)) {
1052                 dwc3_trace(trace_dwc3_gadget,
1053                                 "ISOC ep %s run out for requests",
1054                                 dep->name);
1055                 dep->flags |= DWC3_EP_PENDING_REQUEST;
1056                 return;
1057         }
1058
1059         /* 4 micro frames in the future */
1060         uf = cur_uf + dep->interval * 4;
1061
1062         __dwc3_gadget_kick_transfer(dep, uf);
1063 }
1064
1065 static void dwc3_gadget_start_isoc(struct dwc3 *dwc,
1066                 struct dwc3_ep *dep, const struct dwc3_event_depevt *event)
1067 {
1068         u32 cur_uf, mask;
1069
1070         mask = ~(dep->interval - 1);
1071         cur_uf = event->parameters & mask;
1072
1073         __dwc3_gadget_start_isoc(dwc, dep, cur_uf);
1074 }
1075
1076 static int __dwc3_gadget_ep_queue(struct dwc3_ep *dep, struct dwc3_request *req)
1077 {
1078         struct dwc3             *dwc = dep->dwc;
1079         int                     ret;
1080
1081         if (!dep->endpoint.desc) {
1082                 dwc3_trace(trace_dwc3_gadget,
1083                                 "trying to queue request %p to disabled %s",
1084                                 &req->request, dep->endpoint.name);
1085                 return -ESHUTDOWN;
1086         }
1087
1088         if (WARN(req->dep != dep, "request %p belongs to '%s'\n",
1089                                 &req->request, req->dep->name)) {
1090                 dwc3_trace(trace_dwc3_gadget, "request %p belongs to '%s'",
1091                                 &req->request, req->dep->name);
1092                 return -EINVAL;
1093         }
1094
1095         pm_runtime_get(dwc->dev);
1096
1097         req->request.actual     = 0;
1098         req->request.status     = -EINPROGRESS;
1099         req->direction          = dep->direction;
1100         req->epnum              = dep->number;
1101
1102         trace_dwc3_ep_queue(req);
1103
1104         /*
1105          * Per databook, the total size of buffer must be a multiple
1106          * of MaxPacketSize for OUT endpoints. And MaxPacketSize is
1107          * configed for endpoints in dwc3_gadget_set_ep_config(),
1108          * set to usb_endpoint_descriptor->wMaxPacketSize.
1109          */
1110         if (dep->direction == 0 &&
1111             req->request.length % dep->endpoint.desc->wMaxPacketSize)
1112                 req->request.length = roundup(req->request.length,
1113                                         dep->endpoint.desc->wMaxPacketSize);
1114
1115         /*
1116          * We only add to our list of requests now and
1117          * start consuming the list once we get XferNotReady
1118          * IRQ.
1119          *
1120          * That way, we avoid doing anything that we don't need
1121          * to do now and defer it until the point we receive a
1122          * particular token from the Host side.
1123          *
1124          * This will also avoid Host cancelling URBs due to too
1125          * many NAKs.
1126          */
1127         ret = usb_gadget_map_request(&dwc->gadget, &req->request,
1128                         dep->direction);
1129         if (ret)
1130                 return ret;
1131
1132         list_add_tail(&req->list, &dep->pending_list);
1133
1134         /*
1135          * If there are no pending requests and the endpoint isn't already
1136          * busy, we will just start the request straight away.
1137          *
1138          * This will save one IRQ (XFER_NOT_READY) and possibly make it a
1139          * little bit faster.
1140          */
1141         if (!usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
1142                         !usb_endpoint_xfer_int(dep->endpoint.desc)) {
1143                 ret = __dwc3_gadget_kick_transfer(dep, 0);
1144                 goto out;
1145         }
1146
1147         /*
1148          * There are a few special cases:
1149          *
1150          * 1. XferNotReady with empty list of requests. We need to kick the
1151          *    transfer here in that situation, otherwise we will be NAKing
1152          *    forever. If we get XferNotReady before gadget driver has a
1153          *    chance to queue a request, we will ACK the IRQ but won't be
1154          *    able to receive the data until the next request is queued.
1155          *    The following code is handling exactly that.
1156          *
1157          */
1158         if (dep->flags & DWC3_EP_PENDING_REQUEST) {
1159                 /*
1160                  * If xfernotready is already elapsed and it is a case
1161                  * of isoc transfer, then issue END TRANSFER, so that
1162                  * you can receive xfernotready again and can have
1163                  * notion of current microframe.
1164                  */
1165                 if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
1166                         if (list_empty(&dep->started_list)) {
1167                                 dwc3_stop_active_transfer(dwc, dep->number, true);
1168                                 dep->flags = DWC3_EP_ENABLED;
1169                         }
1170                         return 0;
1171                 }
1172
1173                 ret = __dwc3_gadget_kick_transfer(dep, 0);
1174                 if (!ret)
1175                         dep->flags &= ~DWC3_EP_PENDING_REQUEST;
1176
1177                 goto out;
1178         }
1179
1180         /*
1181          * 2. XferInProgress on Isoc EP with an active transfer. We need to
1182          *    kick the transfer here after queuing a request, otherwise the
1183          *    core may not see the modified TRB(s).
1184          */
1185         if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
1186                         (dep->flags & DWC3_EP_BUSY) &&
1187                         !(dep->flags & DWC3_EP_MISSED_ISOC)) {
1188                 WARN_ON_ONCE(!dep->resource_index);
1189                 ret = __dwc3_gadget_kick_transfer(dep, dep->resource_index);
1190                 goto out;
1191         }
1192
1193         /*
1194          * 4. Stream Capable Bulk Endpoints. We need to start the transfer
1195          * right away, otherwise host will not know we have streams to be
1196          * handled.
1197          */
1198         if (dep->stream_capable)
1199                 ret = __dwc3_gadget_kick_transfer(dep, 0);
1200
1201 out:
1202         if (ret && ret != -EBUSY)
1203                 dwc3_trace(trace_dwc3_gadget,
1204                                 "%s: failed to kick transfers",
1205                                 dep->name);
1206         if (ret == -EBUSY)
1207                 ret = 0;
1208
1209         return ret;
1210 }
1211
1212 static void __dwc3_gadget_ep_zlp_complete(struct usb_ep *ep,
1213                 struct usb_request *request)
1214 {
1215         dwc3_gadget_ep_free_request(ep, request);
1216 }
1217
1218 static int __dwc3_gadget_ep_queue_zlp(struct dwc3 *dwc, struct dwc3_ep *dep)
1219 {
1220         struct dwc3_request             *req;
1221         struct usb_request              *request;
1222         struct usb_ep                   *ep = &dep->endpoint;
1223
1224         dwc3_trace(trace_dwc3_gadget, "queueing ZLP");
1225         request = dwc3_gadget_ep_alloc_request(ep, GFP_ATOMIC);
1226         if (!request)
1227                 return -ENOMEM;
1228
1229         request->length = 0;
1230         request->buf = dwc->zlp_buf;
1231         request->complete = __dwc3_gadget_ep_zlp_complete;
1232
1233         req = to_dwc3_request(request);
1234
1235         return __dwc3_gadget_ep_queue(dep, req);
1236 }
1237
1238 static int dwc3_gadget_ep_queue(struct usb_ep *ep, struct usb_request *request,
1239         gfp_t gfp_flags)
1240 {
1241         struct dwc3_request             *req = to_dwc3_request(request);
1242         struct dwc3_ep                  *dep = to_dwc3_ep(ep);
1243         struct dwc3                     *dwc = dep->dwc;
1244
1245         unsigned long                   flags;
1246
1247         int                             ret;
1248
1249         spin_lock_irqsave(&dwc->lock, flags);
1250         ret = __dwc3_gadget_ep_queue(dep, req);
1251
1252         /*
1253          * Okay, here's the thing, if gadget driver has requested for a ZLP by
1254          * setting request->zero, instead of doing magic, we will just queue an
1255          * extra usb_request ourselves so that it gets handled the same way as
1256          * any other request.
1257          */
1258         if (ret == 0 && request->zero && request->length &&
1259             (request->length % ep->desc->wMaxPacketSize == 0))
1260                 ret = __dwc3_gadget_ep_queue_zlp(dwc, dep);
1261
1262         spin_unlock_irqrestore(&dwc->lock, flags);
1263
1264         return ret;
1265 }
1266
1267 static int dwc3_gadget_ep_dequeue(struct usb_ep *ep,
1268                 struct usb_request *request)
1269 {
1270         struct dwc3_request             *req = to_dwc3_request(request);
1271         struct dwc3_request             *r = NULL;
1272
1273         struct dwc3_ep                  *dep = to_dwc3_ep(ep);
1274         struct dwc3                     *dwc = dep->dwc;
1275
1276         unsigned long                   flags;
1277         int                             ret = 0;
1278
1279         trace_dwc3_ep_dequeue(req);
1280
1281         spin_lock_irqsave(&dwc->lock, flags);
1282
1283         list_for_each_entry(r, &dep->pending_list, list) {
1284                 if (r == req)
1285                         break;
1286         }
1287
1288         if (r != req) {
1289                 list_for_each_entry(r, &dep->started_list, list) {
1290                         if (r == req)
1291                                 break;
1292                 }
1293                 if (r == req) {
1294                         /* wait until it is processed */
1295                         dwc3_stop_active_transfer(dwc, dep->number, true);
1296                         goto out1;
1297                 }
1298                 dev_err(dwc->dev, "request %p was not queued to %s\n",
1299                                 request, ep->name);
1300                 ret = -EINVAL;
1301                 goto out0;
1302         }
1303
1304 out1:
1305         /* giveback the request */
1306         dwc3_gadget_giveback(dep, req, -ECONNRESET);
1307
1308 out0:
1309         spin_unlock_irqrestore(&dwc->lock, flags);
1310
1311         return ret;
1312 }
1313
1314 int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
1315 {
1316         struct dwc3_gadget_ep_cmd_params        params;
1317         struct dwc3                             *dwc = dep->dwc;
1318         int                                     ret;
1319
1320         if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
1321                 dev_err(dwc->dev, "%s is of Isochronous type\n", dep->name);
1322                 return -EINVAL;
1323         }
1324
1325         memset(&params, 0x00, sizeof(params));
1326
1327         if (value) {
1328                 struct dwc3_trb *trb;
1329
1330                 unsigned transfer_in_flight;
1331                 unsigned started;
1332
1333                 if (dep->number > 1)
1334                         trb = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
1335                 else
1336                         trb = &dwc->ep0_trb[dep->trb_enqueue];
1337
1338                 transfer_in_flight = trb->ctrl & DWC3_TRB_CTRL_HWO;
1339                 started = !list_empty(&dep->started_list);
1340
1341                 if (!protocol && ((dep->direction && transfer_in_flight) ||
1342                                 (!dep->direction && started))) {
1343                         dwc3_trace(trace_dwc3_gadget,
1344                                         "%s: pending request, cannot halt",
1345                                         dep->name);
1346                         return -EAGAIN;
1347                 }
1348
1349                 ret = dwc3_send_gadget_ep_cmd(dep, DWC3_DEPCMD_SETSTALL,
1350                                 &params);
1351                 if (ret)
1352                         dev_err(dwc->dev, "failed to set STALL on %s\n",
1353                                         dep->name);
1354                 else
1355                         dep->flags |= DWC3_EP_STALL;
1356         } else {
1357
1358                 ret = dwc3_send_clear_stall_ep_cmd(dep);
1359                 if (ret)
1360                         dev_err(dwc->dev, "failed to clear STALL on %s\n",
1361                                         dep->name);
1362                 else
1363                         dep->flags &= ~(DWC3_EP_STALL | DWC3_EP_WEDGE);
1364         }
1365
1366         return ret;
1367 }
1368
1369 static int dwc3_gadget_ep_set_halt(struct usb_ep *ep, int value)
1370 {
1371         struct dwc3_ep                  *dep = to_dwc3_ep(ep);
1372         struct dwc3                     *dwc = dep->dwc;
1373
1374         unsigned long                   flags;
1375
1376         int                             ret;
1377
1378         spin_lock_irqsave(&dwc->lock, flags);
1379         ret = __dwc3_gadget_ep_set_halt(dep, value, false);
1380         spin_unlock_irqrestore(&dwc->lock, flags);
1381
1382         return ret;
1383 }
1384
1385 static int dwc3_gadget_ep_set_wedge(struct usb_ep *ep)
1386 {
1387         struct dwc3_ep                  *dep = to_dwc3_ep(ep);
1388         struct dwc3                     *dwc = dep->dwc;
1389         unsigned long                   flags;
1390         int                             ret;
1391
1392         spin_lock_irqsave(&dwc->lock, flags);
1393         dep->flags |= DWC3_EP_WEDGE;
1394
1395         if (dep->number == 0 || dep->number == 1)
1396                 ret = __dwc3_gadget_ep0_set_halt(ep, 1);
1397         else
1398                 ret = __dwc3_gadget_ep_set_halt(dep, 1, false);
1399         spin_unlock_irqrestore(&dwc->lock, flags);
1400
1401         return ret;
1402 }
1403
1404 /* -------------------------------------------------------------------------- */
1405
1406 static struct usb_endpoint_descriptor dwc3_gadget_ep0_desc = {
1407         .bLength        = USB_DT_ENDPOINT_SIZE,
1408         .bDescriptorType = USB_DT_ENDPOINT,
1409         .bmAttributes   = USB_ENDPOINT_XFER_CONTROL,
1410 };
1411
1412 static const struct usb_ep_ops dwc3_gadget_ep0_ops = {
1413         .enable         = dwc3_gadget_ep0_enable,
1414         .disable        = dwc3_gadget_ep0_disable,
1415         .alloc_request  = dwc3_gadget_ep_alloc_request,
1416         .free_request   = dwc3_gadget_ep_free_request,
1417         .queue          = dwc3_gadget_ep0_queue,
1418         .dequeue        = dwc3_gadget_ep_dequeue,
1419         .set_halt       = dwc3_gadget_ep0_set_halt,
1420         .set_wedge      = dwc3_gadget_ep_set_wedge,
1421 };
1422
1423 static const struct usb_ep_ops dwc3_gadget_ep_ops = {
1424         .enable         = dwc3_gadget_ep_enable,
1425         .disable        = dwc3_gadget_ep_disable,
1426         .alloc_request  = dwc3_gadget_ep_alloc_request,
1427         .free_request   = dwc3_gadget_ep_free_request,
1428         .queue          = dwc3_gadget_ep_queue,
1429         .dequeue        = dwc3_gadget_ep_dequeue,
1430         .set_halt       = dwc3_gadget_ep_set_halt,
1431         .set_wedge      = dwc3_gadget_ep_set_wedge,
1432 };
1433
1434 /* -------------------------------------------------------------------------- */
1435
1436 static int dwc3_gadget_get_frame(struct usb_gadget *g)
1437 {
1438         struct dwc3             *dwc = gadget_to_dwc(g);
1439         u32                     reg;
1440
1441         reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1442         return DWC3_DSTS_SOFFN(reg);
1443 }
1444
1445 static int __dwc3_gadget_wakeup(struct dwc3 *dwc)
1446 {
1447         unsigned long           timeout;
1448
1449         int                     ret;
1450         u32                     reg;
1451
1452         u8                      link_state;
1453         u8                      speed;
1454
1455         /*
1456          * According to the Databook Remote wakeup request should
1457          * be issued only when the device is in early suspend state.
1458          *
1459          * We can check that via USB Link State bits in DSTS register.
1460          */
1461         reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1462
1463         speed = reg & DWC3_DSTS_CONNECTSPD;
1464         if (speed == DWC3_DSTS_SUPERSPEED) {
1465                 dwc3_trace(trace_dwc3_gadget, "no wakeup on SuperSpeed");
1466                 return 0;
1467         }
1468
1469         link_state = DWC3_DSTS_USBLNKST(reg);
1470
1471         switch (link_state) {
1472         case DWC3_LINK_STATE_RX_DET:    /* in HS, means Early Suspend */
1473         case DWC3_LINK_STATE_U3:        /* in HS, means SUSPEND */
1474                 break;
1475         default:
1476                 dwc3_trace(trace_dwc3_gadget,
1477                                 "can't wakeup from '%s'",
1478                                 dwc3_gadget_link_string(link_state));
1479                 return -EINVAL;
1480         }
1481
1482         ret = dwc3_gadget_set_link_state(dwc, DWC3_LINK_STATE_RECOV);
1483         if (ret < 0) {
1484                 dev_err(dwc->dev, "failed to put link in Recovery\n");
1485                 return ret;
1486         }
1487
1488         /* Recent versions do this automatically */
1489         if (dwc->revision < DWC3_REVISION_194A) {
1490                 /* write zeroes to Link Change Request */
1491                 reg = dwc3_readl(dwc->regs, DWC3_DCTL);
1492                 reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
1493                 dwc3_writel(dwc->regs, DWC3_DCTL, reg);
1494         }
1495
1496         /* poll until Link State changes to ON */
1497         timeout = jiffies + msecs_to_jiffies(100);
1498
1499         while (!time_after(jiffies, timeout)) {
1500                 reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1501
1502                 /* in HS, means ON */
1503                 if (DWC3_DSTS_USBLNKST(reg) == DWC3_LINK_STATE_U0)
1504                         break;
1505         }
1506
1507         if (DWC3_DSTS_USBLNKST(reg) != DWC3_LINK_STATE_U0) {
1508                 dev_err(dwc->dev, "failed to send remote wakeup\n");
1509                 return -EINVAL;
1510         }
1511
1512         return 0;
1513 }
1514
1515 static int dwc3_gadget_wakeup(struct usb_gadget *g)
1516 {
1517         struct dwc3             *dwc = gadget_to_dwc(g);
1518         unsigned long           flags;
1519         int                     ret;
1520
1521         spin_lock_irqsave(&dwc->lock, flags);
1522         ret = __dwc3_gadget_wakeup(dwc);
1523         spin_unlock_irqrestore(&dwc->lock, flags);
1524
1525         return ret;
1526 }
1527
1528 static int dwc3_gadget_set_selfpowered(struct usb_gadget *g,
1529                 int is_selfpowered)
1530 {
1531         struct dwc3             *dwc = gadget_to_dwc(g);
1532         unsigned long           flags;
1533
1534         spin_lock_irqsave(&dwc->lock, flags);
1535         g->is_selfpowered = !!is_selfpowered;
1536         spin_unlock_irqrestore(&dwc->lock, flags);
1537
1538         return 0;
1539 }
1540
1541 static int dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on, int suspend)
1542 {
1543         u32                     reg;
1544         u32                     timeout = 500;
1545
1546         if (pm_runtime_suspended(dwc->dev))
1547                 return 0;
1548
1549         reg = dwc3_readl(dwc->regs, DWC3_DCTL);
1550         if (is_on) {
1551                 if (dwc->revision <= DWC3_REVISION_187A) {
1552                         reg &= ~DWC3_DCTL_TRGTULST_MASK;
1553                         reg |= DWC3_DCTL_TRGTULST_RX_DET;
1554                 }
1555
1556                 if (dwc->revision >= DWC3_REVISION_194A)
1557                         reg &= ~DWC3_DCTL_KEEP_CONNECT;
1558                 reg |= DWC3_DCTL_RUN_STOP;
1559
1560                 if (dwc->has_hibernation)
1561                         reg |= DWC3_DCTL_KEEP_CONNECT;
1562
1563                 dwc->pullups_connected = true;
1564         } else {
1565                 reg &= ~DWC3_DCTL_RUN_STOP;
1566
1567                 if (dwc->has_hibernation && !suspend)
1568                         reg &= ~DWC3_DCTL_KEEP_CONNECT;
1569
1570                 dwc->pullups_connected = false;
1571         }
1572
1573         dwc3_writel(dwc->regs, DWC3_DCTL, reg);
1574
1575         do {
1576                 reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1577                 reg &= DWC3_DSTS_DEVCTRLHLT;
1578         } while (--timeout && !(!is_on ^ !reg));
1579
1580         if (!timeout)
1581                 return -ETIMEDOUT;
1582
1583         dwc3_trace(trace_dwc3_gadget, "gadget %s data soft-%s",
1584                         dwc->gadget_driver
1585                         ? dwc->gadget_driver->function : "no-function",
1586                         is_on ? "connect" : "disconnect");
1587
1588         return 0;
1589 }
1590
1591 static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
1592 {
1593         struct dwc3             *dwc = gadget_to_dwc(g);
1594         unsigned long           flags;
1595         int                     ret;
1596
1597         is_on = !!is_on;
1598
1599         spin_lock_irqsave(&dwc->lock, flags);
1600         ret = dwc3_gadget_run_stop(dwc, is_on, false);
1601         spin_unlock_irqrestore(&dwc->lock, flags);
1602
1603         return ret;
1604 }
1605
1606 static void dwc3_gadget_enable_irq(struct dwc3 *dwc)
1607 {
1608         u32                     reg;
1609
1610         /* Enable all but Start and End of Frame IRQs */
1611         reg = (DWC3_DEVTEN_VNDRDEVTSTRCVEDEN |
1612                         DWC3_DEVTEN_EVNTOVERFLOWEN |
1613                         DWC3_DEVTEN_CMDCMPLTEN |
1614                         DWC3_DEVTEN_ERRTICERREN |
1615                         DWC3_DEVTEN_WKUPEVTEN |
1616                         DWC3_DEVTEN_ULSTCNGEN |
1617                         DWC3_DEVTEN_CONNECTDONEEN |
1618                         DWC3_DEVTEN_USBRSTEN |
1619                         DWC3_DEVTEN_DISCONNEVTEN);
1620
1621         dwc3_writel(dwc->regs, DWC3_DEVTEN, reg);
1622 }
1623
1624 static void dwc3_gadget_disable_irq(struct dwc3 *dwc)
1625 {
1626         /* mask all interrupts */
1627         dwc3_writel(dwc->regs, DWC3_DEVTEN, 0x00);
1628 }
1629
1630 static irqreturn_t dwc3_interrupt(int irq, void *_dwc);
1631 static irqreturn_t dwc3_thread_interrupt(int irq, void *_dwc);
1632
1633 /**
1634  * dwc3_gadget_setup_nump - Calculate and initialize NUMP field of DCFG
1635  * dwc: pointer to our context structure
1636  *
1637  * The following looks like complex but it's actually very simple. In order to
1638  * calculate the number of packets we can burst at once on OUT transfers, we're
1639  * gonna use RxFIFO size.
1640  *
1641  * To calculate RxFIFO size we need two numbers:
1642  * MDWIDTH = size, in bits, of the internal memory bus
1643  * RAM2_DEPTH = depth, in MDWIDTH, of internal RAM2 (where RxFIFO sits)
1644  *
1645  * Given these two numbers, the formula is simple:
1646  *
1647  * RxFIFO Size = (RAM2_DEPTH * MDWIDTH / 8) - 24 - 16;
1648  *
1649  * 24 bytes is for 3x SETUP packets
1650  * 16 bytes is a clock domain crossing tolerance
1651  *
1652  * Given RxFIFO Size, NUMP = RxFIFOSize / 1024;
1653  */
1654 static void dwc3_gadget_setup_nump(struct dwc3 *dwc)
1655 {
1656         u32 ram2_depth;
1657         u32 mdwidth;
1658         u32 nump;
1659         u32 reg;
1660
1661         ram2_depth = DWC3_GHWPARAMS7_RAM2_DEPTH(dwc->hwparams.hwparams7);
1662         mdwidth = DWC3_GHWPARAMS0_MDWIDTH(dwc->hwparams.hwparams0);
1663
1664         nump = ((ram2_depth * mdwidth / 8) - 24 - 16) / 1024;
1665         nump = min_t(u32, nump, 16);
1666
1667         /* update NumP */
1668         reg = dwc3_readl(dwc->regs, DWC3_DCFG);
1669         reg &= ~DWC3_DCFG_NUMP_MASK;
1670         reg |= nump << DWC3_DCFG_NUMP_SHIFT;
1671         dwc3_writel(dwc->regs, DWC3_DCFG, reg);
1672 }
1673
1674 static int __dwc3_gadget_start(struct dwc3 *dwc)
1675 {
1676         struct dwc3_ep          *dep;
1677         int                     ret = 0;
1678         u32                     reg;
1679
1680         reg = dwc3_readl(dwc->regs, DWC3_DCFG);
1681         reg &= ~(DWC3_DCFG_SPEED_MASK);
1682
1683         /**
1684          * WORKAROUND: DWC3 revision < 2.20a have an issue
1685          * which would cause metastability state on Run/Stop
1686          * bit if we try to force the IP to USB2-only mode.
1687          *
1688          * Because of that, we cannot configure the IP to any
1689          * speed other than the SuperSpeed
1690          *
1691          * Refers to:
1692          *
1693          * STAR#9000525659: Clock Domain Crossing on DCTL in
1694          * USB 2.0 Mode
1695          */
1696         if (dwc->revision < DWC3_REVISION_220A) {
1697                 reg |= DWC3_DCFG_SUPERSPEED;
1698         } else {
1699                 switch (dwc->maximum_speed) {
1700                 case USB_SPEED_LOW:
1701                         reg |= DWC3_DCFG_LOWSPEED;
1702                         break;
1703                 case USB_SPEED_FULL:
1704                         reg |= DWC3_DCFG_FULLSPEED1;
1705                         break;
1706                 case USB_SPEED_HIGH:
1707                         reg |= DWC3_DCFG_HIGHSPEED;
1708                         break;
1709                 case USB_SPEED_SUPER:   /* FALLTHROUGH */
1710                 case USB_SPEED_UNKNOWN: /* FALTHROUGH */
1711                 default:
1712                         reg |= DWC3_DCFG_SUPERSPEED;
1713                 }
1714         }
1715         dwc3_writel(dwc->regs, DWC3_DCFG, reg);
1716
1717         /*
1718          * We are telling dwc3 that we want to use DCFG.NUMP as ACK TP's NUMP
1719          * field instead of letting dwc3 itself calculate that automatically.
1720          *
1721          * This way, we maximize the chances that we'll be able to get several
1722          * bursts of data without going through any sort of endpoint throttling.
1723          */
1724         reg = dwc3_readl(dwc->regs, DWC3_GRXTHRCFG);
1725         reg &= ~DWC3_GRXTHRCFG_PKTCNTSEL;
1726         dwc3_writel(dwc->regs, DWC3_GRXTHRCFG, reg);
1727
1728         dwc3_gadget_setup_nump(dwc);
1729
1730         /* Start with SuperSpeed Default */
1731         dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
1732
1733         dep = dwc->eps[0];
1734         ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false,
1735                         false);
1736         if (ret) {
1737                 dev_err(dwc->dev, "failed to enable %s\n", dep->name);
1738                 goto err0;
1739         }
1740
1741         dep = dwc->eps[1];
1742         ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false,
1743                         false);
1744         if (ret) {
1745                 dev_err(dwc->dev, "failed to enable %s\n", dep->name);
1746                 goto err1;
1747         }
1748
1749         /* begin to receive SETUP packets */
1750         dwc->ep0state = EP0_SETUP_PHASE;
1751         dwc3_ep0_out_start(dwc);
1752
1753         dwc3_gadget_enable_irq(dwc);
1754
1755         return 0;
1756
1757 err1:
1758         __dwc3_gadget_ep_disable(dwc->eps[0]);
1759
1760 err0:
1761         return ret;
1762 }
1763
1764 static int dwc3_gadget_start(struct usb_gadget *g,
1765                 struct usb_gadget_driver *driver)
1766 {
1767         struct dwc3             *dwc = gadget_to_dwc(g);
1768         unsigned long           flags;
1769         int                     ret = 0;
1770         int                     irq;
1771
1772         irq = platform_get_irq(to_platform_device(dwc->dev), 0);
1773         ret = request_threaded_irq(irq, dwc3_interrupt, dwc3_thread_interrupt,
1774                         IRQF_SHARED, "dwc3", dwc->ev_buf);
1775         if (ret) {
1776                 dev_err(dwc->dev, "failed to request irq #%d --> %d\n",
1777                                 irq, ret);
1778                 goto err0;
1779         }
1780         dwc->irq_gadget = irq;
1781
1782         spin_lock_irqsave(&dwc->lock, flags);
1783         if (dwc->gadget_driver) {
1784                 dev_err(dwc->dev, "%s is already bound to %s\n",
1785                                 dwc->gadget.name,
1786                                 dwc->gadget_driver->driver.name);
1787                 ret = -EBUSY;
1788                 goto err1;
1789         }
1790
1791         dwc->gadget_driver      = driver;
1792
1793         if (pm_runtime_active(dwc->dev))
1794                 __dwc3_gadget_start(dwc);
1795
1796         spin_unlock_irqrestore(&dwc->lock, flags);
1797
1798         return 0;
1799
1800 err1:
1801         spin_unlock_irqrestore(&dwc->lock, flags);
1802         free_irq(irq, dwc);
1803
1804 err0:
1805         return ret;
1806 }
1807
1808 static void __dwc3_gadget_stop(struct dwc3 *dwc)
1809 {
1810         if (pm_runtime_suspended(dwc->dev))
1811                 return;
1812
1813         dwc3_gadget_disable_irq(dwc);
1814         __dwc3_gadget_ep_disable(dwc->eps[0]);
1815         __dwc3_gadget_ep_disable(dwc->eps[1]);
1816 }
1817
1818 static int dwc3_gadget_stop(struct usb_gadget *g)
1819 {
1820         struct dwc3             *dwc = gadget_to_dwc(g);
1821         unsigned long           flags;
1822
1823         spin_lock_irqsave(&dwc->lock, flags);
1824         __dwc3_gadget_stop(dwc);
1825         dwc->gadget_driver      = NULL;
1826         spin_unlock_irqrestore(&dwc->lock, flags);
1827
1828         free_irq(dwc->irq_gadget, dwc->ev_buf);
1829
1830         return 0;
1831 }
1832
1833 static const struct usb_gadget_ops dwc3_gadget_ops = {
1834         .get_frame              = dwc3_gadget_get_frame,
1835         .wakeup                 = dwc3_gadget_wakeup,
1836         .set_selfpowered        = dwc3_gadget_set_selfpowered,
1837         .pullup                 = dwc3_gadget_pullup,
1838         .udc_start              = dwc3_gadget_start,
1839         .udc_stop               = dwc3_gadget_stop,
1840 };
1841
1842 /* -------------------------------------------------------------------------- */
1843
1844 static int dwc3_gadget_init_hw_endpoints(struct dwc3 *dwc,
1845                 u8 num, u32 direction)
1846 {
1847         struct dwc3_ep                  *dep;
1848         u8                              i;
1849
1850         for (i = 0; i < num; i++) {
1851                 u8 epnum = (i << 1) | (direction ? 1 : 0);
1852
1853                 dep = kzalloc(sizeof(*dep), GFP_KERNEL);
1854                 if (!dep)
1855                         return -ENOMEM;
1856
1857                 dep->dwc = dwc;
1858                 dep->number = epnum;
1859                 dep->direction = !!direction;
1860                 dep->regs = dwc->regs + DWC3_DEP_BASE(epnum);
1861                 dwc->eps[epnum] = dep;
1862
1863                 snprintf(dep->name, sizeof(dep->name), "ep%d%s", epnum >> 1,
1864                                 (epnum & 1) ? "in" : "out");
1865
1866                 dep->endpoint.name = dep->name;
1867                 spin_lock_init(&dep->lock);
1868
1869                 dwc3_trace(trace_dwc3_gadget, "initializing %s", dep->name);
1870
1871                 if (epnum == 0 || epnum == 1) {
1872                         usb_ep_set_maxpacket_limit(&dep->endpoint, 512);
1873                         dep->endpoint.maxburst = 1;
1874                         dep->endpoint.ops = &dwc3_gadget_ep0_ops;
1875                         if (!epnum)
1876                                 dwc->gadget.ep0 = &dep->endpoint;
1877                 } else {
1878                         int             ret;
1879
1880                         usb_ep_set_maxpacket_limit(&dep->endpoint, 1024);
1881                         dep->endpoint.max_streams = 15;
1882                         dep->endpoint.ops = &dwc3_gadget_ep_ops;
1883                         list_add_tail(&dep->endpoint.ep_list,
1884                                         &dwc->gadget.ep_list);
1885
1886                         ret = dwc3_alloc_trb_pool(dep);
1887                         if (ret)
1888                                 return ret;
1889                 }
1890
1891                 if (epnum == 0 || epnum == 1) {
1892                         dep->endpoint.caps.type_control = true;
1893                 } else {
1894                         dep->endpoint.caps.type_iso = true;
1895                         dep->endpoint.caps.type_bulk = true;
1896                         dep->endpoint.caps.type_int = true;
1897                 }
1898
1899                 dep->endpoint.caps.dir_in = !!direction;
1900                 dep->endpoint.caps.dir_out = !direction;
1901
1902                 INIT_LIST_HEAD(&dep->pending_list);
1903                 INIT_LIST_HEAD(&dep->started_list);
1904         }
1905
1906         return 0;
1907 }
1908
1909 static int dwc3_gadget_init_endpoints(struct dwc3 *dwc)
1910 {
1911         int                             ret;
1912
1913         INIT_LIST_HEAD(&dwc->gadget.ep_list);
1914
1915         ret = dwc3_gadget_init_hw_endpoints(dwc, dwc->num_out_eps, 0);
1916         if (ret < 0) {
1917                 dwc3_trace(trace_dwc3_gadget,
1918                                 "failed to allocate OUT endpoints");
1919                 return ret;
1920         }
1921
1922         ret = dwc3_gadget_init_hw_endpoints(dwc, dwc->num_in_eps, 1);
1923         if (ret < 0) {
1924                 dwc3_trace(trace_dwc3_gadget,
1925                                 "failed to allocate IN endpoints");
1926                 return ret;
1927         }
1928
1929         return 0;
1930 }
1931
1932 static void dwc3_gadget_free_endpoints(struct dwc3 *dwc)
1933 {
1934         struct dwc3_ep                  *dep;
1935         u8                              epnum;
1936
1937         for (epnum = 0; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
1938                 dep = dwc->eps[epnum];
1939                 if (!dep)
1940                         continue;
1941                 /*
1942                  * Physical endpoints 0 and 1 are special; they form the
1943                  * bi-directional USB endpoint 0.
1944                  *
1945                  * For those two physical endpoints, we don't allocate a TRB
1946                  * pool nor do we add them the endpoints list. Due to that, we
1947                  * shouldn't do these two operations otherwise we would end up
1948                  * with all sorts of bugs when removing dwc3.ko.
1949                  */
1950                 if (epnum != 0 && epnum != 1) {
1951                         dwc3_free_trb_pool(dep);
1952                         list_del(&dep->endpoint.ep_list);
1953                 }
1954
1955                 kfree(dep);
1956         }
1957 }
1958
1959 /* -------------------------------------------------------------------------- */
1960
1961 static int __dwc3_cleanup_done_trbs(struct dwc3 *dwc, struct dwc3_ep *dep,
1962                 struct dwc3_request *req, struct dwc3_trb *trb,
1963                 const struct dwc3_event_depevt *event, int status)
1964 {
1965         unsigned int            count;
1966         unsigned int            s_pkt = 0;
1967         unsigned int            trb_status;
1968
1969         dep->queued_requests--;
1970         trace_dwc3_complete_trb(dep, trb);
1971
1972         if ((trb->ctrl & DWC3_TRB_CTRL_HWO) && status != -ESHUTDOWN)
1973                 /*
1974                  * We continue despite the error. There is not much we
1975                  * can do. If we don't clean it up we loop forever. If
1976                  * we skip the TRB then it gets overwritten after a
1977                  * while since we use them in a ring buffer. A BUG()
1978                  * would help. Lets hope that if this occurs, someone
1979                  * fixes the root cause instead of looking away :)
1980                  */
1981                 dev_err(dwc->dev, "%s's TRB (%p) still owned by HW\n",
1982                                 dep->name, trb);
1983         count = trb->size & DWC3_TRB_SIZE_MASK;
1984
1985         if (dep->direction) {
1986                 if (count) {
1987                         trb_status = DWC3_TRB_SIZE_TRBSTS(trb->size);
1988                         if (trb_status == DWC3_TRBSTS_MISSED_ISOC) {
1989                                 dwc3_trace(trace_dwc3_gadget,
1990                                                 "%s: incomplete IN transfer",
1991                                                 dep->name);
1992                                 /*
1993                                  * If missed isoc occurred and there is
1994                                  * no request queued then issue END
1995                                  * TRANSFER, so that core generates
1996                                  * next xfernotready and we will issue
1997                                  * a fresh START TRANSFER.
1998                                  * If there are still queued request
1999                                  * then wait, do not issue either END
2000                                  * or UPDATE TRANSFER, just attach next
2001                                  * request in pending_list during
2002                                  * giveback.If any future queued request
2003                                  * is successfully transferred then we
2004                                  * will issue UPDATE TRANSFER for all
2005                                  * request in the pending_list.
2006                                  */
2007                                 dep->flags |= DWC3_EP_MISSED_ISOC;
2008                         } else {
2009                                 dev_err(dwc->dev, "incomplete IN transfer %s\n",
2010                                                 dep->name);
2011                                 status = -ECONNRESET;
2012                         }
2013                 } else {
2014                         dep->flags &= ~DWC3_EP_MISSED_ISOC;
2015                 }
2016         } else {
2017                 if (count && (event->status & DEPEVT_STATUS_SHORT))
2018                         s_pkt = 1;
2019         }
2020
2021         /*
2022          * We assume here we will always receive the entire data block
2023          * which we should receive. Meaning, if we program RX to
2024          * receive 4K but we receive only 2K, we assume that's all we
2025          * should receive and we simply bounce the request back to the
2026          * gadget driver for further processing.
2027          */
2028         req->request.actual += req->request.length - count;
2029         if (s_pkt)
2030                 return 1;
2031         if ((event->status & DEPEVT_STATUS_LST) &&
2032                         (trb->ctrl & (DWC3_TRB_CTRL_LST |
2033                                 DWC3_TRB_CTRL_HWO)))
2034                 return 1;
2035         if ((event->status & DEPEVT_STATUS_IOC) &&
2036                         (trb->ctrl & DWC3_TRB_CTRL_IOC))
2037                 return 1;
2038         return 0;
2039 }
2040
2041 static int dwc3_cleanup_done_reqs(struct dwc3 *dwc, struct dwc3_ep *dep,
2042                 const struct dwc3_event_depevt *event, int status)
2043 {
2044         struct dwc3_request     *req;
2045         struct dwc3_trb         *trb;
2046         unsigned int            slot;
2047         unsigned int            i;
2048         int                     ret;
2049
2050         do {
2051                 req = next_request(&dep->started_list);
2052                 if (WARN_ON_ONCE(!req))
2053                         return 1;
2054
2055                 i = 0;
2056                 do {
2057                         slot = req->first_trb_index + i;
2058                         if (slot == DWC3_TRB_NUM - 1)
2059                                 slot++;
2060                         slot %= DWC3_TRB_NUM;
2061                         trb = &dep->trb_pool[slot];
2062
2063                         ret = __dwc3_cleanup_done_trbs(dwc, dep, req, trb,
2064                                         event, status);
2065                         if (ret)
2066                                 break;
2067                 } while (++i < req->request.num_mapped_sgs);
2068
2069                 dwc3_gadget_giveback(dep, req, status);
2070
2071                 if (ret)
2072                         break;
2073         } while (1);
2074
2075         /*
2076          * Our endpoint might get disabled by another thread during
2077          * dwc3_gadget_giveback(). If that happens, we're just gonna return 1
2078          * early on so DWC3_EP_BUSY flag gets cleared
2079          */
2080         if (!dep->endpoint.desc)
2081                 return 1;
2082
2083         if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
2084                         list_empty(&dep->started_list)) {
2085                 if (list_empty(&dep->pending_list)) {
2086                         /*
2087                          * If there is no entry in request list then do
2088                          * not issue END TRANSFER now. Just set PENDING
2089                          * flag, so that END TRANSFER is issued when an
2090                          * entry is added into request list.
2091                          */
2092                         dep->flags = DWC3_EP_PENDING_REQUEST;
2093                 } else {
2094                         dwc3_stop_active_transfer(dwc, dep->number, true);
2095                         dep->flags = DWC3_EP_ENABLED;
2096                 }
2097                 return 1;
2098         }
2099
2100         if (usb_endpoint_xfer_isoc(dep->endpoint.desc))
2101                 if ((event->status & DEPEVT_STATUS_IOC) &&
2102                                 (trb->ctrl & DWC3_TRB_CTRL_IOC))
2103                         return 0;
2104         return 1;
2105 }
2106
2107 static void dwc3_endpoint_transfer_complete(struct dwc3 *dwc,
2108                 struct dwc3_ep *dep, const struct dwc3_event_depevt *event)
2109 {
2110         unsigned                status = 0;
2111         int                     clean_busy;
2112         u32                     is_xfer_complete;
2113
2114         is_xfer_complete = (event->endpoint_event == DWC3_DEPEVT_XFERCOMPLETE);
2115
2116         if (event->status & DEPEVT_STATUS_BUSERR)
2117                 status = -ECONNRESET;
2118
2119         clean_busy = dwc3_cleanup_done_reqs(dwc, dep, event, status);
2120         if (clean_busy && (!dep->endpoint.desc || is_xfer_complete ||
2121                                 usb_endpoint_xfer_isoc(dep->endpoint.desc)))
2122                 dep->flags &= ~DWC3_EP_BUSY;
2123
2124         /*
2125          * WORKAROUND: This is the 2nd half of U1/U2 -> U0 workaround.
2126          * See dwc3_gadget_linksts_change_interrupt() for 1st half.
2127          */
2128         if (dwc->revision < DWC3_REVISION_183A) {
2129                 u32             reg;
2130                 int             i;
2131
2132                 for (i = 0; i < DWC3_ENDPOINTS_NUM; i++) {
2133                         dep = dwc->eps[i];
2134
2135                         if (!(dep->flags & DWC3_EP_ENABLED))
2136                                 continue;
2137
2138                         if (!list_empty(&dep->started_list))
2139                                 return;
2140                 }
2141
2142                 reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2143                 reg |= dwc->u1u2;
2144                 dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2145
2146                 dwc->u1u2 = 0;
2147         }
2148
2149         /*
2150          * Our endpoint might get disabled by another thread during
2151          * dwc3_gadget_giveback(). If that happens, we're just gonna return 1
2152          * early on so DWC3_EP_BUSY flag gets cleared
2153          */
2154         if (!dep->endpoint.desc)
2155                 return;
2156
2157         if (!usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
2158                 int ret;
2159
2160                 ret = __dwc3_gadget_kick_transfer(dep, 0);
2161                 if (!ret || ret == -EBUSY)
2162                         return;
2163         }
2164 }
2165
2166 static void dwc3_endpoint_interrupt(struct dwc3 *dwc,
2167                 const struct dwc3_event_depevt *event)
2168 {
2169         struct dwc3_ep          *dep;
2170         u8                      epnum = event->endpoint_number;
2171
2172         dep = dwc->eps[epnum];
2173
2174         if (!(dep->flags & DWC3_EP_ENABLED))
2175                 return;
2176
2177         if (epnum == 0 || epnum == 1) {
2178                 dwc3_ep0_interrupt(dwc, event);
2179                 return;
2180         }
2181
2182         switch (event->endpoint_event) {
2183         case DWC3_DEPEVT_XFERCOMPLETE:
2184                 dep->resource_index = 0;
2185
2186                 if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
2187                         dwc3_trace(trace_dwc3_gadget,
2188                                         "%s is an Isochronous endpoint",
2189                                         dep->name);
2190                         return;
2191                 }
2192
2193                 dwc3_endpoint_transfer_complete(dwc, dep, event);
2194                 break;
2195         case DWC3_DEPEVT_XFERINPROGRESS:
2196                 dwc3_endpoint_transfer_complete(dwc, dep, event);
2197                 break;
2198         case DWC3_DEPEVT_XFERNOTREADY:
2199                 if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
2200                         dwc3_gadget_start_isoc(dwc, dep, event);
2201                 } else {
2202                         int active;
2203                         int ret;
2204
2205                         active = event->status & DEPEVT_STATUS_TRANSFER_ACTIVE;
2206
2207                         dwc3_trace(trace_dwc3_gadget, "%s: reason %s",
2208                                         dep->name, active ? "Transfer Active"
2209                                         : "Transfer Not Active");
2210
2211                         ret = __dwc3_gadget_kick_transfer(dep, 0);
2212                         if (!ret || ret == -EBUSY)
2213                                 return;
2214
2215                         dwc3_trace(trace_dwc3_gadget,
2216                                         "%s: failed to kick transfers",
2217                                         dep->name);
2218                 }
2219
2220                 break;
2221         case DWC3_DEPEVT_STREAMEVT:
2222                 if (!usb_endpoint_xfer_bulk(dep->endpoint.desc)) {
2223                         dev_err(dwc->dev, "Stream event for non-Bulk %s\n",
2224                                         dep->name);
2225                         return;
2226                 }
2227
2228                 switch (event->status) {
2229                 case DEPEVT_STREAMEVT_FOUND:
2230                         dwc3_trace(trace_dwc3_gadget,
2231                                         "Stream %d found and started",
2232                                         event->parameters);
2233
2234                         break;
2235                 case DEPEVT_STREAMEVT_NOTFOUND:
2236                         /* FALLTHROUGH */
2237                 default:
2238                         dwc3_trace(trace_dwc3_gadget,
2239                                         "unable to find suitable stream");
2240                 }
2241                 break;
2242         case DWC3_DEPEVT_RXTXFIFOEVT:
2243                 dwc3_trace(trace_dwc3_gadget, "%s FIFO Overrun", dep->name);
2244                 break;
2245         case DWC3_DEPEVT_EPCMDCMPLT:
2246                 dwc3_trace(trace_dwc3_gadget, "Endpoint Command Complete");
2247                 break;
2248         }
2249 }
2250
2251 static void dwc3_disconnect_gadget(struct dwc3 *dwc)
2252 {
2253         if (dwc->gadget_driver && dwc->gadget_driver->disconnect) {
2254                 spin_unlock(&dwc->lock);
2255                 dwc->gadget_driver->disconnect(&dwc->gadget);
2256                 spin_lock(&dwc->lock);
2257         }
2258 }
2259
2260 static void dwc3_suspend_gadget(struct dwc3 *dwc)
2261 {
2262         if (dwc->gadget_driver && dwc->gadget_driver->suspend) {
2263                 spin_unlock(&dwc->lock);
2264                 dwc->gadget_driver->suspend(&dwc->gadget);
2265                 spin_lock(&dwc->lock);
2266         }
2267 }
2268
2269 static void dwc3_resume_gadget(struct dwc3 *dwc)
2270 {
2271         if (dwc->gadget_driver && dwc->gadget_driver->resume) {
2272                 spin_unlock(&dwc->lock);
2273                 dwc->gadget_driver->resume(&dwc->gadget);
2274                 spin_lock(&dwc->lock);
2275         }
2276 }
2277
2278 static void dwc3_reset_gadget(struct dwc3 *dwc)
2279 {
2280         if (!dwc->gadget_driver)
2281                 return;
2282
2283         if (dwc->gadget.speed != USB_SPEED_UNKNOWN) {
2284                 spin_unlock(&dwc->lock);
2285                 usb_gadget_udc_reset(&dwc->gadget, dwc->gadget_driver);
2286                 spin_lock(&dwc->lock);
2287         }
2288 }
2289
2290 static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum, bool force)
2291 {
2292         struct dwc3_ep *dep;
2293         struct dwc3_gadget_ep_cmd_params params;
2294         u32 cmd;
2295         int ret;
2296
2297         dep = dwc->eps[epnum];
2298
2299         if (!dep->resource_index)
2300                 return;
2301
2302         /*
2303          * NOTICE: We are violating what the Databook says about the
2304          * EndTransfer command. Ideally we would _always_ wait for the
2305          * EndTransfer Command Completion IRQ, but that's causing too
2306          * much trouble synchronizing between us and gadget driver.
2307          *
2308          * We have discussed this with the IP Provider and it was
2309          * suggested to giveback all requests here, but give HW some
2310          * extra time to synchronize with the interconnect. We're using
2311          * an arbitrary 100us delay for that.
2312          *
2313          * Note also that a similar handling was tested by Synopsys
2314          * (thanks a lot Paul) and nothing bad has come out of it.
2315          * In short, what we're doing is:
2316          *
2317          * - Issue EndTransfer WITH CMDIOC bit set
2318          * - Wait 100us
2319          */
2320
2321         cmd = DWC3_DEPCMD_ENDTRANSFER;
2322         cmd |= force ? DWC3_DEPCMD_HIPRI_FORCERM : 0;
2323         cmd |= DWC3_DEPCMD_CMDIOC;
2324         cmd |= DWC3_DEPCMD_PARAM(dep->resource_index);
2325         memset(&params, 0, sizeof(params));
2326         ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
2327         WARN_ON_ONCE(ret);
2328         dep->resource_index = 0;
2329         dep->flags &= ~DWC3_EP_BUSY;
2330         udelay(100);
2331 }
2332
2333 static void dwc3_stop_active_transfers(struct dwc3 *dwc)
2334 {
2335         u32 epnum;
2336
2337         for (epnum = 2; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
2338                 struct dwc3_ep *dep;
2339
2340                 dep = dwc->eps[epnum];
2341                 if (!dep)
2342                         continue;
2343
2344                 if (!(dep->flags & DWC3_EP_ENABLED))
2345                         continue;
2346
2347                 dwc3_remove_requests(dwc, dep);
2348         }
2349 }
2350
2351 static void dwc3_clear_stall_all_ep(struct dwc3 *dwc)
2352 {
2353         u32 epnum;
2354
2355         for (epnum = 1; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
2356                 struct dwc3_ep *dep;
2357                 int ret;
2358
2359                 dep = dwc->eps[epnum];
2360                 if (!dep)
2361                         continue;
2362
2363                 if (!(dep->flags & DWC3_EP_STALL))
2364                         continue;
2365
2366                 dep->flags &= ~DWC3_EP_STALL;
2367
2368                 ret = dwc3_send_clear_stall_ep_cmd(dep);
2369                 WARN_ON_ONCE(ret);
2370         }
2371 }
2372
2373 static void dwc3_gadget_disconnect_interrupt(struct dwc3 *dwc)
2374 {
2375         int                     reg;
2376
2377         reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2378         reg &= ~DWC3_DCTL_INITU1ENA;
2379         dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2380
2381         reg &= ~DWC3_DCTL_INITU2ENA;
2382         dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2383
2384         dwc3_disconnect_gadget(dwc);
2385
2386         dwc->gadget.speed = USB_SPEED_UNKNOWN;
2387         dwc->setup_packet_pending = false;
2388         usb_gadget_set_state(&dwc->gadget, USB_STATE_NOTATTACHED);
2389
2390         dwc->connected = false;
2391 }
2392
2393 static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc)
2394 {
2395         u32                     reg;
2396
2397         dwc->connected = true;
2398
2399         /*
2400          * WORKAROUND: DWC3 revisions <1.88a have an issue which
2401          * would cause a missing Disconnect Event if there's a
2402          * pending Setup Packet in the FIFO.
2403          *
2404          * There's no suggested workaround on the official Bug
2405          * report, which states that "unless the driver/application
2406          * is doing any special handling of a disconnect event,
2407          * there is no functional issue".
2408          *
2409          * Unfortunately, it turns out that we _do_ some special
2410          * handling of a disconnect event, namely complete all
2411          * pending transfers, notify gadget driver of the
2412          * disconnection, and so on.
2413          *
2414          * Our suggested workaround is to follow the Disconnect
2415          * Event steps here, instead, based on a setup_packet_pending
2416          * flag. Such flag gets set whenever we have a SETUP_PENDING
2417          * status for EP0 TRBs and gets cleared on XferComplete for the
2418          * same endpoint.
2419          *
2420          * Refers to:
2421          *
2422          * STAR#9000466709: RTL: Device : Disconnect event not
2423          * generated if setup packet pending in FIFO
2424          */
2425         if (dwc->revision < DWC3_REVISION_188A) {
2426                 if (dwc->setup_packet_pending)
2427                         dwc3_gadget_disconnect_interrupt(dwc);
2428         }
2429
2430         dwc3_reset_gadget(dwc);
2431
2432         reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2433         reg &= ~DWC3_DCTL_TSTCTRL_MASK;
2434         dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2435         dwc->test_mode = false;
2436
2437         dwc3_stop_active_transfers(dwc);
2438         dwc3_clear_stall_all_ep(dwc);
2439
2440         /* Reset device address to zero */
2441         reg = dwc3_readl(dwc->regs, DWC3_DCFG);
2442         reg &= ~(DWC3_DCFG_DEVADDR_MASK);
2443         dwc3_writel(dwc->regs, DWC3_DCFG, reg);
2444 }
2445
2446 static void dwc3_update_ram_clk_sel(struct dwc3 *dwc, u32 speed)
2447 {
2448         u32 reg;
2449         u32 usb30_clock = DWC3_GCTL_CLK_BUS;
2450
2451         /*
2452          * We change the clock only at SS but I dunno why I would want to do
2453          * this. Maybe it becomes part of the power saving plan.
2454          */
2455
2456         if (speed != DWC3_DSTS_SUPERSPEED)
2457                 return;
2458
2459         /*
2460          * RAMClkSel is reset to 0 after USB reset, so it must be reprogrammed
2461          * each time on Connect Done.
2462          */
2463         if (!usb30_clock)
2464                 return;
2465
2466         reg = dwc3_readl(dwc->regs, DWC3_GCTL);
2467         reg |= DWC3_GCTL_RAMCLKSEL(usb30_clock);
2468         dwc3_writel(dwc->regs, DWC3_GCTL, reg);
2469 }
2470
2471 static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
2472 {
2473         struct dwc3_ep          *dep;
2474         int                     ret;
2475         u32                     reg;
2476         u8                      speed;
2477
2478         reg = dwc3_readl(dwc->regs, DWC3_DSTS);
2479         speed = reg & DWC3_DSTS_CONNECTSPD;
2480         dwc->speed = speed;
2481
2482         dwc3_update_ram_clk_sel(dwc, speed);
2483
2484         switch (speed) {
2485         case DWC3_DSTS_SUPERSPEED:
2486                 /*
2487                  * WORKAROUND: DWC3 revisions <1.90a have an issue which
2488                  * would cause a missing USB3 Reset event.
2489                  *
2490                  * In such situations, we should force a USB3 Reset
2491                  * event by calling our dwc3_gadget_reset_interrupt()
2492                  * routine.
2493                  *
2494                  * Refers to:
2495                  *
2496                  * STAR#9000483510: RTL: SS : USB3 reset event may
2497                  * not be generated always when the link enters poll
2498                  */
2499                 if (dwc->revision < DWC3_REVISION_190A)
2500                         dwc3_gadget_reset_interrupt(dwc);
2501
2502                 dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
2503                 dwc->gadget.ep0->maxpacket = 512;
2504                 dwc->gadget.speed = USB_SPEED_SUPER;
2505                 break;
2506         case DWC3_DSTS_HIGHSPEED:
2507                 dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
2508                 dwc->gadget.ep0->maxpacket = 64;
2509                 dwc->gadget.speed = USB_SPEED_HIGH;
2510                 break;
2511         case DWC3_DSTS_FULLSPEED2:
2512         case DWC3_DSTS_FULLSPEED1:
2513                 dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
2514                 dwc->gadget.ep0->maxpacket = 64;
2515                 dwc->gadget.speed = USB_SPEED_FULL;
2516                 break;
2517         case DWC3_DSTS_LOWSPEED:
2518                 dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(8);
2519                 dwc->gadget.ep0->maxpacket = 8;
2520                 dwc->gadget.speed = USB_SPEED_LOW;
2521                 break;
2522         }
2523
2524         /* Enable USB2 LPM Capability */
2525
2526         if ((dwc->revision > DWC3_REVISION_194A) &&
2527             (speed != DWC3_DSTS_SUPERSPEED)) {
2528                 reg = dwc3_readl(dwc->regs, DWC3_DCFG);
2529                 reg |= DWC3_DCFG_LPM_CAP;
2530                 dwc3_writel(dwc->regs, DWC3_DCFG, reg);
2531
2532                 reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2533                 reg &= ~(DWC3_DCTL_HIRD_THRES_MASK | DWC3_DCTL_L1_HIBER_EN);
2534
2535                 reg |= DWC3_DCTL_HIRD_THRES(dwc->hird_threshold);
2536
2537                 /*
2538                  * When dwc3 revisions >= 2.40a, LPM Erratum is enabled and
2539                  * DCFG.LPMCap is set, core responses with an ACK and the
2540                  * BESL value in the LPM token is less than or equal to LPM
2541                  * NYET threshold.
2542                  */
2543                 WARN_ONCE(dwc->revision < DWC3_REVISION_240A
2544                                 && dwc->has_lpm_erratum,
2545                                 "LPM Erratum not available on dwc3 revisisions < 2.40a\n");
2546
2547                 if (dwc->has_lpm_erratum && dwc->revision >= DWC3_REVISION_240A)
2548                         reg |= DWC3_DCTL_LPM_ERRATA(dwc->lpm_nyet_threshold);
2549
2550                 dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2551         } else {
2552                 reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2553                 reg &= ~DWC3_DCTL_HIRD_THRES_MASK;
2554                 dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2555         }
2556
2557         dep = dwc->eps[0];
2558         ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, true,
2559                         false);
2560         if (ret) {
2561                 dev_err(dwc->dev, "failed to enable %s\n", dep->name);
2562                 return;
2563         }
2564
2565         dep = dwc->eps[1];
2566         ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, true,
2567                         false);
2568         if (ret) {
2569                 dev_err(dwc->dev, "failed to enable %s\n", dep->name);
2570                 return;
2571         }
2572
2573         /*
2574          * Configure PHY via GUSB3PIPECTLn if required.
2575          *
2576          * Update GTXFIFOSIZn
2577          *
2578          * In both cases reset values should be sufficient.
2579          */
2580 }
2581
2582 static void dwc3_gadget_wakeup_interrupt(struct dwc3 *dwc)
2583 {
2584         /*
2585          * TODO take core out of low power mode when that's
2586          * implemented.
2587          */
2588
2589         if (dwc->gadget_driver && dwc->gadget_driver->resume) {
2590                 spin_unlock(&dwc->lock);
2591                 dwc->gadget_driver->resume(&dwc->gadget);
2592                 spin_lock(&dwc->lock);
2593         }
2594 }
2595
2596 static void dwc3_gadget_linksts_change_interrupt(struct dwc3 *dwc,
2597                 unsigned int evtinfo)
2598 {
2599         enum dwc3_link_state    next = evtinfo & DWC3_LINK_STATE_MASK;
2600         unsigned int            pwropt;
2601
2602         /*
2603          * WORKAROUND: DWC3 < 2.50a have an issue when configured without
2604          * Hibernation mode enabled which would show up when device detects
2605          * host-initiated U3 exit.
2606          *
2607          * In that case, device will generate a Link State Change Interrupt
2608          * from U3 to RESUME which is only necessary if Hibernation is
2609          * configured in.
2610          *
2611          * There are no functional changes due to such spurious event and we
2612          * just need to ignore it.
2613          *
2614          * Refers to:
2615          *
2616          * STAR#9000570034 RTL: SS Resume event generated in non-Hibernation
2617          * operational mode
2618          */
2619         pwropt = DWC3_GHWPARAMS1_EN_PWROPT(dwc->hwparams.hwparams1);
2620         if ((dwc->revision < DWC3_REVISION_250A) &&
2621                         (pwropt != DWC3_GHWPARAMS1_EN_PWROPT_HIB)) {
2622                 if ((dwc->link_state == DWC3_LINK_STATE_U3) &&
2623                                 (next == DWC3_LINK_STATE_RESUME)) {
2624                         dwc3_trace(trace_dwc3_gadget,
2625                                         "ignoring transition U3 -> Resume");
2626                         return;
2627                 }
2628         }
2629
2630         /*
2631          * WORKAROUND: DWC3 Revisions <1.83a have an issue which, depending
2632          * on the link partner, the USB session might do multiple entry/exit
2633          * of low power states before a transfer takes place.
2634          *
2635          * Due to this problem, we might experience lower throughput. The
2636          * suggested workaround is to disable DCTL[12:9] bits if we're
2637          * transitioning from U1/U2 to U0 and enable those bits again
2638          * after a transfer completes and there are no pending transfers
2639          * on any of the enabled endpoints.
2640          *
2641          * This is the first half of that workaround.
2642          *
2643          * Refers to:
2644          *
2645          * STAR#9000446952: RTL: Device SS : if U1/U2 ->U0 takes >128us
2646          * core send LGO_Ux entering U0
2647          */
2648         if (dwc->revision < DWC3_REVISION_183A) {
2649                 if (next == DWC3_LINK_STATE_U0) {
2650                         u32     u1u2;
2651                         u32     reg;
2652
2653                         switch (dwc->link_state) {
2654                         case DWC3_LINK_STATE_U1:
2655                         case DWC3_LINK_STATE_U2:
2656                                 reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2657                                 u1u2 = reg & (DWC3_DCTL_INITU2ENA
2658                                                 | DWC3_DCTL_ACCEPTU2ENA
2659                                                 | DWC3_DCTL_INITU1ENA
2660                                                 | DWC3_DCTL_ACCEPTU1ENA);
2661
2662                                 if (!dwc->u1u2)
2663                                         dwc->u1u2 = reg & u1u2;
2664
2665                                 reg &= ~u1u2;
2666
2667                                 dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2668                                 break;
2669                         default:
2670                                 /* do nothing */
2671                                 break;
2672                         }
2673                 }
2674         }
2675
2676         switch (next) {
2677         case DWC3_LINK_STATE_U1:
2678                 if (dwc->speed == USB_SPEED_SUPER)
2679                         dwc3_suspend_gadget(dwc);
2680                 break;
2681         case DWC3_LINK_STATE_U2:
2682         case DWC3_LINK_STATE_U3:
2683                 dwc3_suspend_gadget(dwc);
2684                 break;
2685         case DWC3_LINK_STATE_RESUME:
2686                 dwc3_resume_gadget(dwc);
2687                 break;
2688         default:
2689                 /* do nothing */
2690                 break;
2691         }
2692
2693         dwc->link_state = next;
2694 }
2695
2696 static void dwc3_gadget_hibernation_interrupt(struct dwc3 *dwc,
2697                 unsigned int evtinfo)
2698 {
2699         unsigned int is_ss = evtinfo & BIT(4);
2700
2701         /**
2702          * WORKAROUND: DWC3 revison 2.20a with hibernation support
2703          * have a known issue which can cause USB CV TD.9.23 to fail
2704          * randomly.
2705          *
2706          * Because of this issue, core could generate bogus hibernation
2707          * events which SW needs to ignore.
2708          *
2709          * Refers to:
2710          *
2711          * STAR#9000546576: Device Mode Hibernation: Issue in USB 2.0
2712          * Device Fallback from SuperSpeed
2713          */
2714         if (is_ss ^ (dwc->speed == USB_SPEED_SUPER))
2715                 return;
2716
2717         /* enter hibernation here */
2718 }
2719
2720 static void dwc3_gadget_interrupt(struct dwc3 *dwc,
2721                 const struct dwc3_event_devt *event)
2722 {
2723         switch (event->type) {
2724         case DWC3_DEVICE_EVENT_DISCONNECT:
2725                 dwc3_gadget_disconnect_interrupt(dwc);
2726                 break;
2727         case DWC3_DEVICE_EVENT_RESET:
2728                 dwc3_gadget_reset_interrupt(dwc);
2729                 break;
2730         case DWC3_DEVICE_EVENT_CONNECT_DONE:
2731                 dwc3_gadget_conndone_interrupt(dwc);
2732                 break;
2733         case DWC3_DEVICE_EVENT_WAKEUP:
2734                 dwc3_gadget_wakeup_interrupt(dwc);
2735                 break;
2736         case DWC3_DEVICE_EVENT_HIBER_REQ:
2737                 if (dev_WARN_ONCE(dwc->dev, !dwc->has_hibernation,
2738                                         "unexpected hibernation event\n"))
2739                         break;
2740
2741                 dwc3_gadget_hibernation_interrupt(dwc, event->event_info);
2742                 break;
2743         case DWC3_DEVICE_EVENT_LINK_STATUS_CHANGE:
2744                 dwc3_gadget_linksts_change_interrupt(dwc, event->event_info);
2745                 break;
2746         case DWC3_DEVICE_EVENT_EOPF:
2747                 dwc3_trace(trace_dwc3_gadget, "End of Periodic Frame");
2748                 break;
2749         case DWC3_DEVICE_EVENT_SOF:
2750                 dwc3_trace(trace_dwc3_gadget, "Start of Periodic Frame");
2751                 break;
2752         case DWC3_DEVICE_EVENT_ERRATIC_ERROR:
2753                 dwc3_trace(trace_dwc3_gadget, "Erratic Error");
2754                 break;
2755         case DWC3_DEVICE_EVENT_CMD_CMPL:
2756                 dwc3_trace(trace_dwc3_gadget, "Command Complete");
2757                 break;
2758         case DWC3_DEVICE_EVENT_OVERFLOW:
2759                 dwc3_trace(trace_dwc3_gadget, "Overflow");
2760                 break;
2761         default:
2762                 dev_WARN(dwc->dev, "UNKNOWN IRQ %d\n", event->type);
2763         }
2764 }
2765
2766 static void dwc3_process_event_entry(struct dwc3 *dwc,
2767                 const union dwc3_event *event)
2768 {
2769         trace_dwc3_event(event->raw);
2770
2771         /* Endpoint IRQ, handle it and return early */
2772         if (event->type.is_devspec == 0) {
2773                 /* depevt */
2774                 return dwc3_endpoint_interrupt(dwc, &event->depevt);
2775         }
2776
2777         switch (event->type.type) {
2778         case DWC3_EVENT_TYPE_DEV:
2779                 dwc3_gadget_interrupt(dwc, &event->devt);
2780                 break;
2781         /* REVISIT what to do with Carkit and I2C events ? */
2782         default:
2783                 dev_err(dwc->dev, "UNKNOWN IRQ type %d\n", event->raw);
2784         }
2785 }
2786
2787 static irqreturn_t dwc3_process_event_buf(struct dwc3_event_buffer *evt)
2788 {
2789         struct dwc3 *dwc = evt->dwc;
2790         irqreturn_t ret = IRQ_NONE;
2791         int left;
2792         u32 reg;
2793
2794         left = evt->count;
2795
2796         if (!(evt->flags & DWC3_EVENT_PENDING))
2797                 return IRQ_NONE;
2798
2799         while (left > 0) {
2800                 union dwc3_event event;
2801
2802                 event.raw = *(u32 *) (evt->buf + evt->lpos);
2803
2804                 dwc3_process_event_entry(dwc, &event);
2805
2806                 /*
2807                  * FIXME we wrap around correctly to the next entry as
2808                  * almost all entries are 4 bytes in size. There is one
2809                  * entry which has 12 bytes which is a regular entry
2810                  * followed by 8 bytes data. ATM I don't know how
2811                  * things are organized if we get next to the a
2812                  * boundary so I worry about that once we try to handle
2813                  * that.
2814                  */
2815                 evt->lpos = (evt->lpos + 4) % DWC3_EVENT_BUFFERS_SIZE;
2816                 left -= 4;
2817
2818                 dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), 4);
2819         }
2820
2821         evt->count = 0;
2822         evt->flags &= ~DWC3_EVENT_PENDING;
2823         ret = IRQ_HANDLED;
2824
2825         /* Unmask interrupt */
2826         reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(0));
2827         reg &= ~DWC3_GEVNTSIZ_INTMASK;
2828         dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), reg);
2829
2830         return ret;
2831 }
2832
2833 static irqreturn_t dwc3_thread_interrupt(int irq, void *_evt)
2834 {
2835         struct dwc3_event_buffer *evt = _evt;
2836         struct dwc3 *dwc = evt->dwc;
2837         unsigned long flags;
2838         irqreturn_t ret = IRQ_NONE;
2839
2840         spin_lock_irqsave(&dwc->lock, flags);
2841         ret = dwc3_process_event_buf(evt);
2842         spin_unlock_irqrestore(&dwc->lock, flags);
2843
2844         return ret;
2845 }
2846
2847 static irqreturn_t dwc3_check_event_buf(struct dwc3_event_buffer *evt)
2848 {
2849         struct dwc3 *dwc = evt->dwc;
2850         u32 count;
2851         u32 reg;
2852
2853         if (pm_runtime_suspended(dwc->dev)) {
2854                 pm_runtime_get(dwc->dev);
2855                 disable_irq_nosync(dwc->irq_gadget);
2856                 dwc->pending_events = true;
2857                 return IRQ_HANDLED;
2858         }
2859
2860         count = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(0));
2861         count &= DWC3_GEVNTCOUNT_MASK;
2862         if (!count)
2863                 return IRQ_NONE;
2864
2865         evt->count = count;
2866         evt->flags |= DWC3_EVENT_PENDING;
2867
2868         /* Mask interrupt */
2869         reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(0));
2870         reg |= DWC3_GEVNTSIZ_INTMASK;
2871         dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), reg);
2872
2873         return IRQ_WAKE_THREAD;
2874 }
2875
2876 static irqreturn_t dwc3_interrupt(int irq, void *_evt)
2877 {
2878         struct dwc3_event_buffer        *evt = _evt;
2879
2880         return dwc3_check_event_buf(evt);
2881 }
2882
2883 /**
2884  * dwc3_gadget_init - Initializes gadget related registers
2885  * @dwc: pointer to our controller context structure
2886  *
2887  * Returns 0 on success otherwise negative errno.
2888  */
2889 int dwc3_gadget_init(struct dwc3 *dwc)
2890 {
2891         int                                     ret;
2892
2893         dwc->ctrl_req = dma_alloc_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
2894                         &dwc->ctrl_req_addr, GFP_KERNEL);
2895         if (!dwc->ctrl_req) {
2896                 dev_err(dwc->dev, "failed to allocate ctrl request\n");
2897                 ret = -ENOMEM;
2898                 goto err0;
2899         }
2900
2901         dwc->ep0_trb = dma_alloc_coherent(dwc->dev, sizeof(*dwc->ep0_trb) * 2,
2902                         &dwc->ep0_trb_addr, GFP_KERNEL);
2903         if (!dwc->ep0_trb) {
2904                 dev_err(dwc->dev, "failed to allocate ep0 trb\n");
2905                 ret = -ENOMEM;
2906                 goto err1;
2907         }
2908
2909         dwc->setup_buf = kzalloc(DWC3_EP0_BOUNCE_SIZE, GFP_KERNEL);
2910         if (!dwc->setup_buf) {
2911                 ret = -ENOMEM;
2912                 goto err2;
2913         }
2914
2915         dwc->ep0_bounce = dma_alloc_coherent(dwc->dev,
2916                         DWC3_EP0_BOUNCE_SIZE, &dwc->ep0_bounce_addr,
2917                         GFP_KERNEL);
2918         if (!dwc->ep0_bounce) {
2919                 dev_err(dwc->dev, "failed to allocate ep0 bounce buffer\n");
2920                 ret = -ENOMEM;
2921                 goto err3;
2922         }
2923
2924         dwc->zlp_buf = kzalloc(DWC3_ZLP_BUF_SIZE, GFP_KERNEL);
2925         if (!dwc->zlp_buf) {
2926                 ret = -ENOMEM;
2927                 goto err4;
2928         }
2929
2930         dwc->gadget.ops                 = &dwc3_gadget_ops;
2931         dwc->gadget.speed               = USB_SPEED_UNKNOWN;
2932         dwc->gadget.sg_supported        = true;
2933         dwc->gadget.name                = "dwc3-gadget";
2934         dwc->gadget.is_otg              = dwc->dr_mode == USB_DR_MODE_OTG;
2935
2936         /*
2937          * FIXME We might be setting max_speed to <SUPER, however versions
2938          * <2.20a of dwc3 have an issue with metastability (documented
2939          * elsewhere in this driver) which tells us we can't set max speed to
2940          * anything lower than SUPER.
2941          *
2942          * Because gadget.max_speed is only used by composite.c and function
2943          * drivers (i.e. it won't go into dwc3's registers) we are allowing this
2944          * to happen so we avoid sending SuperSpeed Capability descriptor
2945          * together with our BOS descriptor as that could confuse host into
2946          * thinking we can handle super speed.
2947          *
2948          * Note that, in fact, we won't even support GetBOS requests when speed
2949          * is less than super speed because we don't have means, yet, to tell
2950          * composite.c that we are USB 2.0 + LPM ECN.
2951          */
2952         if (dwc->revision < DWC3_REVISION_220A)
2953                 dwc3_trace(trace_dwc3_gadget,
2954                                 "Changing max_speed on rev %08x",
2955                                 dwc->revision);
2956
2957         dwc->gadget.max_speed           = dwc->maximum_speed;
2958
2959         /*
2960          * Per databook, DWC3 needs buffer size to be aligned to MaxPacketSize
2961          * on ep out.
2962          */
2963         dwc->gadget.quirk_ep_out_aligned_size = true;
2964
2965         /*
2966          * REVISIT: Here we should clear all pending IRQs to be
2967          * sure we're starting from a well known location.
2968          */
2969
2970         ret = dwc3_gadget_init_endpoints(dwc);
2971         if (ret)
2972                 goto err5;
2973
2974         ret = usb_add_gadget_udc(dwc->dev, &dwc->gadget);
2975         if (ret) {
2976                 dev_err(dwc->dev, "failed to register udc\n");
2977                 goto err5;
2978         }
2979
2980         return 0;
2981
2982 err5:
2983         kfree(dwc->zlp_buf);
2984
2985 err4:
2986         dwc3_gadget_free_endpoints(dwc);
2987         dma_free_coherent(dwc->dev, DWC3_EP0_BOUNCE_SIZE,
2988                         dwc->ep0_bounce, dwc->ep0_bounce_addr);
2989
2990 err3:
2991         kfree(dwc->setup_buf);
2992
2993 err2:
2994         dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb),
2995                         dwc->ep0_trb, dwc->ep0_trb_addr);
2996
2997 err1:
2998         dma_free_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
2999                         dwc->ctrl_req, dwc->ctrl_req_addr);
3000
3001 err0:
3002         return ret;
3003 }
3004
3005 /* -------------------------------------------------------------------------- */
3006
3007 void dwc3_gadget_exit(struct dwc3 *dwc)
3008 {
3009         usb_del_gadget_udc(&dwc->gadget);
3010
3011         dwc3_gadget_free_endpoints(dwc);
3012
3013         dma_free_coherent(dwc->dev, DWC3_EP0_BOUNCE_SIZE,
3014                         dwc->ep0_bounce, dwc->ep0_bounce_addr);
3015
3016         kfree(dwc->setup_buf);
3017         kfree(dwc->zlp_buf);
3018
3019         dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb),
3020                         dwc->ep0_trb, dwc->ep0_trb_addr);
3021
3022         dma_free_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
3023                         dwc->ctrl_req, dwc->ctrl_req_addr);
3024 }
3025
3026 int dwc3_gadget_suspend(struct dwc3 *dwc)
3027 {
3028         int ret;
3029
3030         if (!dwc->gadget_driver)
3031                 return 0;
3032
3033         ret = dwc3_gadget_run_stop(dwc, false, false);
3034         if (ret < 0)
3035                 return ret;
3036
3037         dwc3_disconnect_gadget(dwc);
3038         __dwc3_gadget_stop(dwc);
3039
3040         return 0;
3041 }
3042
3043 int dwc3_gadget_resume(struct dwc3 *dwc)
3044 {
3045         int                     ret;
3046
3047         if (!dwc->gadget_driver)
3048                 return 0;
3049
3050         ret = __dwc3_gadget_start(dwc);
3051         if (ret < 0)
3052                 goto err0;
3053
3054         ret = dwc3_gadget_run_stop(dwc, true, false);
3055         if (ret < 0)
3056                 goto err1;
3057
3058         return 0;
3059
3060 err1:
3061         __dwc3_gadget_stop(dwc);
3062
3063 err0:
3064         return ret;
3065 }
3066
3067 void dwc3_gadget_process_pending_events(struct dwc3 *dwc)
3068 {
3069         if (dwc->pending_events) {
3070                 dwc3_interrupt(dwc->irq_gadget, dwc->ev_buf);
3071                 dwc->pending_events = false;
3072                 enable_irq(dwc->irq_gadget);
3073         }
3074 }