Linux-libre 5.7.6-gnu
[librecmc/linux-libre.git] / drivers / usb / gadget / udc / bdc / bdc_udc.c
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * bdc_udc.c - BRCM BDC USB3.0 device controller gagdet ops
4  *
5  * Copyright (C) 2014 Broadcom Corporation
6  *
7  * Author: Ashwini Pahuja
8  *
9  * Based on drivers under drivers/usb/gadget/udc/
10  */
11 #include <linux/module.h>
12 #include <linux/pci.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/kernel.h>
15 #include <linux/delay.h>
16 #include <linux/ioport.h>
17 #include <linux/sched.h>
18 #include <linux/slab.h>
19 #include <linux/errno.h>
20 #include <linux/init.h>
21 #include <linux/timer.h>
22 #include <linux/list.h>
23 #include <linux/interrupt.h>
24 #include <linux/moduleparam.h>
25 #include <linux/device.h>
26 #include <linux/usb/ch9.h>
27 #include <linux/usb/gadget.h>
28 #include <linux/usb/otg.h>
29 #include <linux/pm.h>
30 #include <linux/io.h>
31 #include <linux/irq.h>
32 #include <asm/unaligned.h>
33 #include <linux/platform_device.h>
34
35 #include "bdc.h"
36 #include "bdc_ep.h"
37 #include "bdc_cmd.h"
38 #include "bdc_dbg.h"
39
40 static const struct usb_gadget_ops bdc_gadget_ops;
41
42 static const char * const conn_speed_str[] =  {
43         "Not connected",
44         "Full Speed",
45         "Low Speed",
46         "High Speed",
47         "Super Speed",
48 };
49
50 /* EP0 initial descripror */
51 static struct usb_endpoint_descriptor bdc_gadget_ep0_desc = {
52         .bLength = USB_DT_ENDPOINT_SIZE,
53         .bDescriptorType = USB_DT_ENDPOINT,
54         .bmAttributes = USB_ENDPOINT_XFER_CONTROL,
55         .bEndpointAddress = 0,
56         .wMaxPacketSize = cpu_to_le16(EP0_MAX_PKT_SIZE),
57 };
58
59 /* Advance the srr dqp maintained by SW */
60 static void srr_dqp_index_advc(struct bdc *bdc, u32 srr_num)
61 {
62         struct srr *srr;
63
64         srr = &bdc->srr;
65         dev_dbg_ratelimited(bdc->dev, "srr->dqp_index:%d\n", srr->dqp_index);
66         srr->dqp_index++;
67         /* rollback to 0 if we are past the last */
68         if (srr->dqp_index == NUM_SR_ENTRIES)
69                 srr->dqp_index = 0;
70 }
71
72 /* connect sr */
73 static void bdc_uspc_connected(struct bdc *bdc)
74 {
75         u32 speed, temp;
76         u32 usppms;
77         int ret;
78
79         temp = bdc_readl(bdc->regs, BDC_USPC);
80         speed = BDC_PSP(temp);
81         dev_dbg(bdc->dev, "%s speed=%x\n", __func__, speed);
82         switch (speed) {
83         case BDC_SPEED_SS:
84                 bdc_gadget_ep0_desc.wMaxPacketSize =
85                                                 cpu_to_le16(EP0_MAX_PKT_SIZE);
86                 bdc->gadget.ep0->maxpacket = EP0_MAX_PKT_SIZE;
87                 bdc->gadget.speed = USB_SPEED_SUPER;
88                 /* Enable U1T in SS mode */
89                 usppms =  bdc_readl(bdc->regs, BDC_USPPMS);
90                 usppms &= ~BDC_U1T(0xff);
91                 usppms |= BDC_U1T(U1_TIMEOUT);
92                 usppms |= BDC_PORT_W1S;
93                 bdc_writel(bdc->regs, BDC_USPPMS, usppms);
94                 break;
95
96         case BDC_SPEED_HS:
97                 bdc_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
98                 bdc->gadget.ep0->maxpacket = 64;
99                 bdc->gadget.speed = USB_SPEED_HIGH;
100                 break;
101
102         case BDC_SPEED_FS:
103                 bdc_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
104                 bdc->gadget.ep0->maxpacket = 64;
105                 bdc->gadget.speed = USB_SPEED_FULL;
106                 break;
107
108         case BDC_SPEED_LS:
109                 bdc_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(8);
110                 bdc->gadget.ep0->maxpacket = 8;
111                 bdc->gadget.speed = USB_SPEED_LOW;
112                 break;
113         default:
114                 dev_err(bdc->dev, "UNDEFINED SPEED\n");
115                 return;
116         }
117         dev_dbg(bdc->dev, "connected at %s\n", conn_speed_str[speed]);
118         /* Now we know the speed, configure ep0 */
119         bdc->bdc_ep_array[1]->desc = &bdc_gadget_ep0_desc;
120         ret = bdc_config_ep(bdc, bdc->bdc_ep_array[1]);
121         if (ret)
122                 dev_err(bdc->dev, "EP0 config failed\n");
123         bdc->bdc_ep_array[1]->usb_ep.desc = &bdc_gadget_ep0_desc;
124         bdc->bdc_ep_array[1]->flags |= BDC_EP_ENABLED;
125         usb_gadget_set_state(&bdc->gadget, USB_STATE_DEFAULT);
126 }
127
128 /* device got disconnected */
129 static void bdc_uspc_disconnected(struct bdc *bdc, bool reinit)
130 {
131         struct bdc_ep *ep;
132
133         dev_dbg(bdc->dev, "%s\n", __func__);
134         /*
135          * Only stop ep0 from here, rest of the endpoints will be disabled
136          * from gadget_disconnect
137          */
138         ep = bdc->bdc_ep_array[1];
139         if (ep && (ep->flags & BDC_EP_ENABLED))
140                 /* if enabled then stop and remove requests */
141                 bdc_ep_disable(ep);
142
143         if (bdc->gadget_driver && bdc->gadget_driver->disconnect) {
144                 spin_unlock(&bdc->lock);
145                 bdc->gadget_driver->disconnect(&bdc->gadget);
146                 spin_lock(&bdc->lock);
147         }
148         /* Set Unknown speed */
149         bdc->gadget.speed = USB_SPEED_UNKNOWN;
150         bdc->devstatus &= DEVSTATUS_CLEAR;
151         bdc->delayed_status = false;
152         bdc->reinit = reinit;
153         bdc->test_mode = false;
154 }
155
156 /* TNotify wkaeup timer */
157 static void bdc_func_wake_timer(struct work_struct *work)
158 {
159         struct bdc *bdc = container_of(work, struct bdc, func_wake_notify.work);
160         unsigned long flags;
161
162         dev_dbg(bdc->dev, "%s\n", __func__);
163         spin_lock_irqsave(&bdc->lock, flags);
164         /*
165          * Check if host has started transferring on endpoints
166          * FUNC_WAKE_ISSUED is cleared when transfer has started after resume
167         */
168         if (bdc->devstatus & FUNC_WAKE_ISSUED) {
169                 dev_dbg(bdc->dev, "FUNC_WAKE_ISSUED FLAG IS STILL SET\n");
170                 /* flag is still set, so again send func wake */
171                 bdc_function_wake_fh(bdc, 0);
172                 schedule_delayed_work(&bdc->func_wake_notify,
173                                                 msecs_to_jiffies(BDC_TNOTIFY));
174         }
175         spin_unlock_irqrestore(&bdc->lock, flags);
176 }
177
178 /* handler for Link state change condition */
179 static void handle_link_state_change(struct bdc *bdc, u32 uspc)
180 {
181         u32 link_state;
182
183         dev_dbg(bdc->dev, "Link state change");
184         link_state = BDC_PST(uspc);
185         switch (link_state) {
186         case BDC_LINK_STATE_U3:
187                 if ((bdc->gadget.speed != USB_SPEED_UNKNOWN) &&
188                                                 bdc->gadget_driver->suspend) {
189                         dev_dbg(bdc->dev, "Entered Suspend mode\n");
190                         spin_unlock(&bdc->lock);
191                         bdc->devstatus |= DEVICE_SUSPENDED;
192                         bdc->gadget_driver->suspend(&bdc->gadget);
193                         spin_lock(&bdc->lock);
194                 }
195                 break;
196         case BDC_LINK_STATE_U0:
197                 if (bdc->devstatus & REMOTE_WAKEUP_ISSUED) {
198                         bdc->devstatus &= ~REMOTE_WAKEUP_ISSUED;
199                         if (bdc->gadget.speed == USB_SPEED_SUPER) {
200                                 bdc_function_wake_fh(bdc, 0);
201                                 bdc->devstatus |= FUNC_WAKE_ISSUED;
202                                 /*
203                                  * Start a Notification timer and check if the
204                                  * Host transferred anything on any of the EPs,
205                                  * if not then send function wake again every
206                                  * TNotification secs until host initiates
207                                  * transfer to BDC, USB3 spec Table 8.13
208                                 */
209                                 schedule_delayed_work(
210                                                 &bdc->func_wake_notify,
211                                                 msecs_to_jiffies(BDC_TNOTIFY));
212                                 dev_dbg(bdc->dev, "sched func_wake_notify\n");
213                         }
214                 }
215                 break;
216
217         case BDC_LINK_STATE_RESUME:
218                 dev_dbg(bdc->dev, "Resumed from Suspend\n");
219                 if (bdc->devstatus & DEVICE_SUSPENDED) {
220                         bdc->gadget_driver->resume(&bdc->gadget);
221                         bdc->devstatus &= ~DEVICE_SUSPENDED;
222                 }
223                 break;
224         default:
225                 dev_dbg(bdc->dev, "link state:%d\n", link_state);
226         }
227 }
228
229 /* something changes on upstream port, handle it here */
230 void bdc_sr_uspc(struct bdc *bdc, struct bdc_sr *sreport)
231 {
232         u32 clear_flags = 0;
233         u32 uspc;
234         bool connected = false;
235         bool disconn = false;
236
237         uspc = bdc_readl(bdc->regs, BDC_USPC);
238         dev_dbg(bdc->dev, "%s uspc=0x%08x\n", __func__, uspc);
239
240         /* Port connect changed */
241         if (uspc & BDC_PCC) {
242                 /* Vbus not present, and not connected to Downstream port */
243                 if ((uspc & BDC_VBC) && !(uspc & BDC_VBS) && !(uspc & BDC_PCS))
244                         disconn = true;
245                 else if ((uspc & BDC_PCS) && !BDC_PST(uspc))
246                         connected = true;
247                 clear_flags |= BDC_PCC;
248         }
249
250         /* Change in VBus and VBus is present */
251         if ((uspc & BDC_VBC) && (uspc & BDC_VBS)) {
252                 if (bdc->pullup) {
253                         dev_dbg(bdc->dev, "Do a softconnect\n");
254                         /* Attached state, do a softconnect */
255                         bdc_softconn(bdc);
256                         usb_gadget_set_state(&bdc->gadget, USB_STATE_POWERED);
257                 }
258                 clear_flags |= BDC_VBC;
259         } else if ((uspc & BDC_PRS) || (uspc & BDC_PRC) || disconn) {
260                 /* Hot reset, warm reset, 2.0 bus reset or disconn */
261                 dev_dbg(bdc->dev, "Port reset or disconn\n");
262                 bdc_uspc_disconnected(bdc, disconn);
263                 clear_flags |= BDC_PRC;
264         } else if ((uspc & BDC_PSC) && (uspc & BDC_PCS)) {
265                 /* Change in Link state */
266                 handle_link_state_change(bdc, uspc);
267                 clear_flags |= BDC_PSC;
268         }
269
270         /*
271          * In SS we might not have PRC bit set before connection, but in 2.0
272          * the PRC bit is set before connection, so moving this condition out
273          * of bus reset to handle both SS/2.0 speeds.
274          */
275         if (connected) {
276                 /* This is the connect event for U0/L0 */
277                 dev_dbg(bdc->dev, "Connected\n");
278                 bdc_uspc_connected(bdc);
279                 bdc->devstatus &= ~(DEVICE_SUSPENDED);
280         }
281         uspc = bdc_readl(bdc->regs, BDC_USPC);
282         uspc &= (~BDC_USPSC_RW);
283         dev_dbg(bdc->dev, "uspc=%x\n", uspc);
284         bdc_writel(bdc->regs, BDC_USPC, clear_flags);
285 }
286
287 /* Main interrupt handler for bdc */
288 static irqreturn_t bdc_udc_interrupt(int irq, void *_bdc)
289 {
290         u32 eqp_index, dqp_index, sr_type, srr_int;
291         struct bdc_sr *sreport;
292         struct bdc *bdc = _bdc;
293         u32 status;
294         int ret;
295
296         spin_lock(&bdc->lock);
297         status = bdc_readl(bdc->regs, BDC_BDCSC);
298         if (!(status & BDC_GIP)) {
299                 spin_unlock(&bdc->lock);
300                 return IRQ_NONE;
301         }
302         srr_int = bdc_readl(bdc->regs, BDC_SRRINT(0));
303         /* Check if the SRR IP bit it set? */
304         if (!(srr_int & BDC_SRR_IP)) {
305                 dev_warn(bdc->dev, "Global irq pending but SRR IP is 0\n");
306                 spin_unlock(&bdc->lock);
307                 return IRQ_NONE;
308         }
309         eqp_index = BDC_SRR_EPI(srr_int);
310         dqp_index = BDC_SRR_DPI(srr_int);
311         dev_dbg(bdc->dev,
312                         "%s eqp_index=%d dqp_index=%d  srr.dqp_index=%d\n\n",
313                          __func__, eqp_index, dqp_index, bdc->srr.dqp_index);
314
315         /* check for ring empty condition */
316         if (eqp_index == dqp_index) {
317                 dev_dbg(bdc->dev, "SRR empty?\n");
318                 spin_unlock(&bdc->lock);
319                 return IRQ_HANDLED;
320         }
321
322         while (bdc->srr.dqp_index != eqp_index) {
323                 sreport = &bdc->srr.sr_bds[bdc->srr.dqp_index];
324                 /* sreport is read before using it */
325                 rmb();
326                 sr_type = le32_to_cpu(sreport->offset[3]) & BD_TYPE_BITMASK;
327                 dev_dbg_ratelimited(bdc->dev, "sr_type=%d\n", sr_type);
328                 switch (sr_type) {
329                 case SR_XSF:
330                         bdc->sr_handler[0](bdc, sreport);
331                         break;
332
333                 case SR_USPC:
334                         bdc->sr_handler[1](bdc, sreport);
335                         break;
336                 default:
337                         dev_warn(bdc->dev, "SR:%d not handled\n", sr_type);
338                 }
339                 /* Advance the srr dqp index */
340                 srr_dqp_index_advc(bdc, 0);
341         }
342         /* update the hw dequeue pointer */
343         srr_int = bdc_readl(bdc->regs, BDC_SRRINT(0));
344         srr_int &= ~BDC_SRR_DPI_MASK;
345         srr_int &= ~(BDC_SRR_RWS|BDC_SRR_RST|BDC_SRR_ISR);
346         srr_int |= ((bdc->srr.dqp_index) << 16);
347         srr_int |= BDC_SRR_IP;
348         bdc_writel(bdc->regs, BDC_SRRINT(0), srr_int);
349         srr_int = bdc_readl(bdc->regs, BDC_SRRINT(0));
350         if (bdc->reinit) {
351                 ret = bdc_reinit(bdc);
352                 if (ret)
353                         dev_err(bdc->dev, "err in bdc reinit\n");
354         }
355
356         spin_unlock(&bdc->lock);
357
358         return IRQ_HANDLED;
359 }
360
361 /* Gadget ops */
362 static int bdc_udc_start(struct usb_gadget *gadget,
363                                 struct usb_gadget_driver *driver)
364 {
365         struct bdc *bdc = gadget_to_bdc(gadget);
366         unsigned long flags;
367         int ret = 0;
368
369         dev_dbg(bdc->dev, "%s()\n", __func__);
370         spin_lock_irqsave(&bdc->lock, flags);
371         if (bdc->gadget_driver) {
372                 dev_err(bdc->dev, "%s is already bound to %s\n",
373                         bdc->gadget.name,
374                         bdc->gadget_driver->driver.name);
375                 ret = -EBUSY;
376                 goto err;
377         }
378         /*
379          * Run the controller from here and when BDC is connected to
380          * Host then driver will receive a USPC SR with VBUS present
381          * and then driver will do a softconnect.
382         */
383         ret = bdc_run(bdc);
384         if (ret) {
385                 dev_err(bdc->dev, "%s bdc run fail\n", __func__);
386                 goto err;
387         }
388         bdc->gadget_driver = driver;
389         bdc->gadget.dev.driver = &driver->driver;
390 err:
391         spin_unlock_irqrestore(&bdc->lock, flags);
392
393         return ret;
394 }
395
396 static int bdc_udc_stop(struct usb_gadget *gadget)
397 {
398         struct bdc *bdc = gadget_to_bdc(gadget);
399         unsigned long flags;
400
401         dev_dbg(bdc->dev, "%s()\n", __func__);
402         spin_lock_irqsave(&bdc->lock, flags);
403         bdc_stop(bdc);
404         bdc->gadget_driver = NULL;
405         bdc->gadget.dev.driver = NULL;
406         spin_unlock_irqrestore(&bdc->lock, flags);
407
408         return 0;
409 }
410
411 static int bdc_udc_pullup(struct usb_gadget *gadget, int is_on)
412 {
413         struct bdc *bdc = gadget_to_bdc(gadget);
414         unsigned long flags;
415         u32 uspc;
416
417         dev_dbg(bdc->dev, "%s() is_on:%d\n", __func__, is_on);
418         if (!gadget)
419                 return -EINVAL;
420
421         spin_lock_irqsave(&bdc->lock, flags);
422         if (!is_on) {
423                 bdc_softdisconn(bdc);
424                 bdc->pullup = false;
425         } else {
426                 /*
427                  * For a self powered device, we need to wait till we receive
428                  * a VBUS change and Vbus present event, then if pullup flag
429                  * is set, then only we present the Termintation.
430                  */
431                 bdc->pullup = true;
432                 /*
433                  * Check if BDC is already connected to Host i.e Vbus=1,
434                  * if yes, then present TERM now, this is typical for bus
435                  * powered devices.
436                  */
437                 uspc = bdc_readl(bdc->regs, BDC_USPC);
438                 if (uspc & BDC_VBS)
439                         bdc_softconn(bdc);
440         }
441         spin_unlock_irqrestore(&bdc->lock, flags);
442
443         return 0;
444 }
445
446 static int bdc_udc_set_selfpowered(struct usb_gadget *gadget,
447                 int is_self)
448 {
449         struct bdc              *bdc = gadget_to_bdc(gadget);
450         unsigned long           flags;
451
452         dev_dbg(bdc->dev, "%s()\n", __func__);
453         gadget->is_selfpowered = (is_self != 0);
454         spin_lock_irqsave(&bdc->lock, flags);
455         if (!is_self)
456                 bdc->devstatus |= 1 << USB_DEVICE_SELF_POWERED;
457         else
458                 bdc->devstatus &= ~(1 << USB_DEVICE_SELF_POWERED);
459
460         spin_unlock_irqrestore(&bdc->lock, flags);
461
462         return 0;
463 }
464
465 static int bdc_udc_wakeup(struct usb_gadget *gadget)
466 {
467         struct bdc *bdc = gadget_to_bdc(gadget);
468         unsigned long           flags;
469         u8      link_state;
470         u32     uspc;
471         int ret = 0;
472
473         dev_dbg(bdc->dev,
474                 "%s() bdc->devstatus=%08x\n",
475                 __func__, bdc->devstatus);
476
477         if (!(bdc->devstatus & REMOTE_WAKE_ENABLE))
478                 return  -EOPNOTSUPP;
479
480         spin_lock_irqsave(&bdc->lock, flags);
481         uspc = bdc_readl(bdc->regs, BDC_USPC);
482         link_state = BDC_PST(uspc);
483         dev_dbg(bdc->dev, "link_state =%d portsc=%x", link_state, uspc);
484         if (link_state != BDC_LINK_STATE_U3) {
485                 dev_warn(bdc->dev,
486                         "can't wakeup from link state %d\n",
487                         link_state);
488                 ret = -EINVAL;
489                 goto out;
490         }
491         if (bdc->gadget.speed == USB_SPEED_SUPER)
492                 bdc->devstatus |= REMOTE_WAKEUP_ISSUED;
493
494         uspc &= ~BDC_PST_MASK;
495         uspc &= (~BDC_USPSC_RW);
496         uspc |=  BDC_PST(BDC_LINK_STATE_U0);
497         uspc |=  BDC_SWS;
498         bdc_writel(bdc->regs, BDC_USPC, uspc);
499         uspc = bdc_readl(bdc->regs, BDC_USPC);
500         link_state = BDC_PST(uspc);
501         dev_dbg(bdc->dev, "link_state =%d portsc=%x", link_state, uspc);
502 out:
503         spin_unlock_irqrestore(&bdc->lock, flags);
504
505         return ret;
506 }
507
508 static const struct usb_gadget_ops bdc_gadget_ops = {
509         .wakeup = bdc_udc_wakeup,
510         .set_selfpowered = bdc_udc_set_selfpowered,
511         .pullup = bdc_udc_pullup,
512         .udc_start = bdc_udc_start,
513         .udc_stop = bdc_udc_stop,
514 };
515
516 /* Init the gadget interface and register the udc */
517 int bdc_udc_init(struct bdc *bdc)
518 {
519         u32 temp;
520         int ret;
521
522         dev_dbg(bdc->dev, "%s()\n", __func__);
523         bdc->gadget.ops = &bdc_gadget_ops;
524         bdc->gadget.max_speed = USB_SPEED_SUPER;
525         bdc->gadget.speed = USB_SPEED_UNKNOWN;
526         bdc->gadget.dev.parent = bdc->dev;
527
528         bdc->gadget.sg_supported = false;
529
530
531         bdc->gadget.name = BRCM_BDC_NAME;
532         ret = devm_request_irq(bdc->dev, bdc->irq, bdc_udc_interrupt,
533                                 IRQF_SHARED , BRCM_BDC_NAME, bdc);
534         if (ret) {
535                 dev_err(bdc->dev,
536                         "failed to request irq #%d %d\n",
537                         bdc->irq, ret);
538                 return ret;
539         }
540
541         ret = bdc_init_ep(bdc);
542         if (ret) {
543                 dev_err(bdc->dev, "bdc init ep fail: %d\n", ret);
544                 return ret;
545         }
546
547         ret = usb_add_gadget_udc(bdc->dev, &bdc->gadget);
548         if (ret) {
549                 dev_err(bdc->dev, "failed to register udc\n");
550                 goto err0;
551         }
552         usb_gadget_set_state(&bdc->gadget, USB_STATE_NOTATTACHED);
553         bdc->bdc_ep_array[1]->desc = &bdc_gadget_ep0_desc;
554         /*
555          * Allocate bd list for ep0 only, ep0 will be enabled on connect
556          * status report when the speed is known
557          */
558         ret = bdc_ep_enable(bdc->bdc_ep_array[1]);
559         if (ret) {
560                 dev_err(bdc->dev, "fail to enable %s\n",
561                                                 bdc->bdc_ep_array[1]->name);
562                 goto err1;
563         }
564         INIT_DELAYED_WORK(&bdc->func_wake_notify, bdc_func_wake_timer);
565         /* Enable Interrupts */
566         temp = bdc_readl(bdc->regs, BDC_BDCSC);
567         temp |= BDC_GIE;
568         bdc_writel(bdc->regs, BDC_BDCSC, temp);
569         return 0;
570 err1:
571         usb_del_gadget_udc(&bdc->gadget);
572 err0:
573         bdc_free_ep(bdc);
574
575         return ret;
576 }
577
578 void bdc_udc_exit(struct bdc *bdc)
579 {
580         unsigned long flags;
581
582         dev_dbg(bdc->dev, "%s()\n", __func__);
583         spin_lock_irqsave(&bdc->lock, flags);
584         bdc_ep_disable(bdc->bdc_ep_array[1]);
585         spin_unlock_irqrestore(&bdc->lock, flags);
586
587         usb_del_gadget_udc(&bdc->gadget);
588         bdc_free_ep(bdc);
589 }