dt-bindings: mtd: ingenic: Use standard ecc-engine property
[linux/fpc-iii.git] / drivers / usb / host / xhci-dbgcap.c
blobc78be578abb065af0e0715352f8c502345907ad7
1 // SPDX-License-Identifier: GPL-2.0
2 /**
3 * xhci-dbgcap.c - xHCI debug capability support
5 * Copyright (C) 2017 Intel Corporation
7 * Author: Lu Baolu <baolu.lu@linux.intel.com>
8 */
9 #include <linux/dma-mapping.h>
10 #include <linux/slab.h>
11 #include <linux/nls.h>
13 #include "xhci.h"
14 #include "xhci-trace.h"
15 #include "xhci-dbgcap.h"
17 static inline void *
18 dbc_dma_alloc_coherent(struct xhci_hcd *xhci, size_t size,
19 dma_addr_t *dma_handle, gfp_t flags)
21 void *vaddr;
23 vaddr = dma_alloc_coherent(xhci_to_hcd(xhci)->self.sysdev,
24 size, dma_handle, flags);
25 memset(vaddr, 0, size);
26 return vaddr;
29 static inline void
30 dbc_dma_free_coherent(struct xhci_hcd *xhci, size_t size,
31 void *cpu_addr, dma_addr_t dma_handle)
33 if (cpu_addr)
34 dma_free_coherent(xhci_to_hcd(xhci)->self.sysdev,
35 size, cpu_addr, dma_handle);
38 static u32 xhci_dbc_populate_strings(struct dbc_str_descs *strings)
40 struct usb_string_descriptor *s_desc;
41 u32 string_length;
43 /* Serial string: */
44 s_desc = (struct usb_string_descriptor *)strings->serial;
45 utf8s_to_utf16s(DBC_STRING_SERIAL, strlen(DBC_STRING_SERIAL),
46 UTF16_LITTLE_ENDIAN, (wchar_t *)s_desc->wData,
47 DBC_MAX_STRING_LENGTH);
49 s_desc->bLength = (strlen(DBC_STRING_SERIAL) + 1) * 2;
50 s_desc->bDescriptorType = USB_DT_STRING;
51 string_length = s_desc->bLength;
52 string_length <<= 8;
54 /* Product string: */
55 s_desc = (struct usb_string_descriptor *)strings->product;
56 utf8s_to_utf16s(DBC_STRING_PRODUCT, strlen(DBC_STRING_PRODUCT),
57 UTF16_LITTLE_ENDIAN, (wchar_t *)s_desc->wData,
58 DBC_MAX_STRING_LENGTH);
60 s_desc->bLength = (strlen(DBC_STRING_PRODUCT) + 1) * 2;
61 s_desc->bDescriptorType = USB_DT_STRING;
62 string_length += s_desc->bLength;
63 string_length <<= 8;
65 /* Manufacture string: */
66 s_desc = (struct usb_string_descriptor *)strings->manufacturer;
67 utf8s_to_utf16s(DBC_STRING_MANUFACTURER,
68 strlen(DBC_STRING_MANUFACTURER),
69 UTF16_LITTLE_ENDIAN, (wchar_t *)s_desc->wData,
70 DBC_MAX_STRING_LENGTH);
72 s_desc->bLength = (strlen(DBC_STRING_MANUFACTURER) + 1) * 2;
73 s_desc->bDescriptorType = USB_DT_STRING;
74 string_length += s_desc->bLength;
75 string_length <<= 8;
77 /* String0: */
78 strings->string0[0] = 4;
79 strings->string0[1] = USB_DT_STRING;
80 strings->string0[2] = 0x09;
81 strings->string0[3] = 0x04;
82 string_length += 4;
84 return string_length;
87 static void xhci_dbc_init_contexts(struct xhci_hcd *xhci, u32 string_length)
89 struct xhci_dbc *dbc;
90 struct dbc_info_context *info;
91 struct xhci_ep_ctx *ep_ctx;
92 u32 dev_info;
93 dma_addr_t deq, dma;
94 unsigned int max_burst;
96 dbc = xhci->dbc;
97 if (!dbc)
98 return;
100 /* Populate info Context: */
101 info = (struct dbc_info_context *)dbc->ctx->bytes;
102 dma = dbc->string_dma;
103 info->string0 = cpu_to_le64(dma);
104 info->manufacturer = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH);
105 info->product = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH * 2);
106 info->serial = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH * 3);
107 info->length = cpu_to_le32(string_length);
109 /* Populate bulk out endpoint context: */
110 ep_ctx = dbc_bulkout_ctx(dbc);
111 max_burst = DBC_CTRL_MAXBURST(readl(&dbc->regs->control));
112 deq = dbc_bulkout_enq(dbc);
113 ep_ctx->ep_info = 0;
114 ep_ctx->ep_info2 = dbc_epctx_info2(BULK_OUT_EP, 1024, max_burst);
115 ep_ctx->deq = cpu_to_le64(deq | dbc->ring_out->cycle_state);
117 /* Populate bulk in endpoint context: */
118 ep_ctx = dbc_bulkin_ctx(dbc);
119 deq = dbc_bulkin_enq(dbc);
120 ep_ctx->ep_info = 0;
121 ep_ctx->ep_info2 = dbc_epctx_info2(BULK_IN_EP, 1024, max_burst);
122 ep_ctx->deq = cpu_to_le64(deq | dbc->ring_in->cycle_state);
124 /* Set DbC context and info registers: */
125 xhci_write_64(xhci, dbc->ctx->dma, &dbc->regs->dccp);
127 dev_info = cpu_to_le32((DBC_VENDOR_ID << 16) | DBC_PROTOCOL);
128 writel(dev_info, &dbc->regs->devinfo1);
130 dev_info = cpu_to_le32((DBC_DEVICE_REV << 16) | DBC_PRODUCT_ID);
131 writel(dev_info, &dbc->regs->devinfo2);
134 static void xhci_dbc_giveback(struct dbc_request *req, int status)
135 __releases(&dbc->lock)
136 __acquires(&dbc->lock)
138 struct dbc_ep *dep = req->dep;
139 struct xhci_dbc *dbc = dep->dbc;
140 struct xhci_hcd *xhci = dbc->xhci;
141 struct device *dev = xhci_to_hcd(dbc->xhci)->self.sysdev;
143 list_del_init(&req->list_pending);
144 req->trb_dma = 0;
145 req->trb = NULL;
147 if (req->status == -EINPROGRESS)
148 req->status = status;
150 trace_xhci_dbc_giveback_request(req);
152 dma_unmap_single(dev,
153 req->dma,
154 req->length,
155 dbc_ep_dma_direction(dep));
157 /* Give back the transfer request: */
158 spin_unlock(&dbc->lock);
159 req->complete(xhci, req);
160 spin_lock(&dbc->lock);
163 static void xhci_dbc_flush_single_request(struct dbc_request *req)
165 union xhci_trb *trb = req->trb;
167 trb->generic.field[0] = 0;
168 trb->generic.field[1] = 0;
169 trb->generic.field[2] = 0;
170 trb->generic.field[3] &= cpu_to_le32(TRB_CYCLE);
171 trb->generic.field[3] |= cpu_to_le32(TRB_TYPE(TRB_TR_NOOP));
173 xhci_dbc_giveback(req, -ESHUTDOWN);
176 static void xhci_dbc_flush_endpoint_requests(struct dbc_ep *dep)
178 struct dbc_request *req, *tmp;
180 list_for_each_entry_safe(req, tmp, &dep->list_pending, list_pending)
181 xhci_dbc_flush_single_request(req);
184 static void xhci_dbc_flush_requests(struct xhci_dbc *dbc)
186 xhci_dbc_flush_endpoint_requests(&dbc->eps[BULK_OUT]);
187 xhci_dbc_flush_endpoint_requests(&dbc->eps[BULK_IN]);
190 struct dbc_request *
191 dbc_alloc_request(struct dbc_ep *dep, gfp_t gfp_flags)
193 struct dbc_request *req;
195 req = kzalloc(sizeof(*req), gfp_flags);
196 if (!req)
197 return NULL;
199 req->dep = dep;
200 INIT_LIST_HEAD(&req->list_pending);
201 INIT_LIST_HEAD(&req->list_pool);
202 req->direction = dep->direction;
204 trace_xhci_dbc_alloc_request(req);
206 return req;
209 void
210 dbc_free_request(struct dbc_ep *dep, struct dbc_request *req)
212 trace_xhci_dbc_free_request(req);
214 kfree(req);
217 static void
218 xhci_dbc_queue_trb(struct xhci_ring *ring, u32 field1,
219 u32 field2, u32 field3, u32 field4)
221 union xhci_trb *trb, *next;
223 trb = ring->enqueue;
224 trb->generic.field[0] = cpu_to_le32(field1);
225 trb->generic.field[1] = cpu_to_le32(field2);
226 trb->generic.field[2] = cpu_to_le32(field3);
227 trb->generic.field[3] = cpu_to_le32(field4);
229 trace_xhci_dbc_gadget_ep_queue(ring, &trb->generic);
231 ring->num_trbs_free--;
232 next = ++(ring->enqueue);
233 if (TRB_TYPE_LINK_LE32(next->link.control)) {
234 next->link.control ^= cpu_to_le32(TRB_CYCLE);
235 ring->enqueue = ring->enq_seg->trbs;
236 ring->cycle_state ^= 1;
240 static int xhci_dbc_queue_bulk_tx(struct dbc_ep *dep,
241 struct dbc_request *req)
243 u64 addr;
244 union xhci_trb *trb;
245 unsigned int num_trbs;
246 struct xhci_dbc *dbc = dep->dbc;
247 struct xhci_ring *ring = dep->ring;
248 u32 length, control, cycle;
250 num_trbs = count_trbs(req->dma, req->length);
251 WARN_ON(num_trbs != 1);
252 if (ring->num_trbs_free < num_trbs)
253 return -EBUSY;
255 addr = req->dma;
256 trb = ring->enqueue;
257 cycle = ring->cycle_state;
258 length = TRB_LEN(req->length);
259 control = TRB_TYPE(TRB_NORMAL) | TRB_IOC;
261 if (cycle)
262 control &= cpu_to_le32(~TRB_CYCLE);
263 else
264 control |= cpu_to_le32(TRB_CYCLE);
266 req->trb = ring->enqueue;
267 req->trb_dma = xhci_trb_virt_to_dma(ring->enq_seg, ring->enqueue);
268 xhci_dbc_queue_trb(ring,
269 lower_32_bits(addr),
270 upper_32_bits(addr),
271 length, control);
274 * Add a barrier between writes of trb fields and flipping
275 * the cycle bit:
277 wmb();
279 if (cycle)
280 trb->generic.field[3] |= cpu_to_le32(TRB_CYCLE);
281 else
282 trb->generic.field[3] &= cpu_to_le32(~TRB_CYCLE);
284 writel(DBC_DOOR_BELL_TARGET(dep->direction), &dbc->regs->doorbell);
286 return 0;
289 static int
290 dbc_ep_do_queue(struct dbc_ep *dep, struct dbc_request *req)
292 int ret;
293 struct device *dev;
294 struct xhci_dbc *dbc = dep->dbc;
295 struct xhci_hcd *xhci = dbc->xhci;
297 dev = xhci_to_hcd(xhci)->self.sysdev;
299 if (!req->length || !req->buf)
300 return -EINVAL;
302 req->actual = 0;
303 req->status = -EINPROGRESS;
305 req->dma = dma_map_single(dev,
306 req->buf,
307 req->length,
308 dbc_ep_dma_direction(dep));
309 if (dma_mapping_error(dev, req->dma)) {
310 xhci_err(xhci, "failed to map buffer\n");
311 return -EFAULT;
314 ret = xhci_dbc_queue_bulk_tx(dep, req);
315 if (ret) {
316 xhci_err(xhci, "failed to queue trbs\n");
317 dma_unmap_single(dev,
318 req->dma,
319 req->length,
320 dbc_ep_dma_direction(dep));
321 return -EFAULT;
324 list_add_tail(&req->list_pending, &dep->list_pending);
326 return 0;
329 int dbc_ep_queue(struct dbc_ep *dep, struct dbc_request *req,
330 gfp_t gfp_flags)
332 unsigned long flags;
333 struct xhci_dbc *dbc = dep->dbc;
334 int ret = -ESHUTDOWN;
336 spin_lock_irqsave(&dbc->lock, flags);
337 if (dbc->state == DS_CONFIGURED)
338 ret = dbc_ep_do_queue(dep, req);
339 spin_unlock_irqrestore(&dbc->lock, flags);
341 mod_delayed_work(system_wq, &dbc->event_work, 0);
343 trace_xhci_dbc_queue_request(req);
345 return ret;
348 static inline void xhci_dbc_do_eps_init(struct xhci_hcd *xhci, bool direction)
350 struct dbc_ep *dep;
351 struct xhci_dbc *dbc = xhci->dbc;
353 dep = &dbc->eps[direction];
354 dep->dbc = dbc;
355 dep->direction = direction;
356 dep->ring = direction ? dbc->ring_in : dbc->ring_out;
358 INIT_LIST_HEAD(&dep->list_pending);
361 static void xhci_dbc_eps_init(struct xhci_hcd *xhci)
363 xhci_dbc_do_eps_init(xhci, BULK_OUT);
364 xhci_dbc_do_eps_init(xhci, BULK_IN);
367 static void xhci_dbc_eps_exit(struct xhci_hcd *xhci)
369 struct xhci_dbc *dbc = xhci->dbc;
371 memset(dbc->eps, 0, sizeof(struct dbc_ep) * ARRAY_SIZE(dbc->eps));
374 static int xhci_dbc_mem_init(struct xhci_hcd *xhci, gfp_t flags)
376 int ret;
377 dma_addr_t deq;
378 u32 string_length;
379 struct xhci_dbc *dbc = xhci->dbc;
381 /* Allocate various rings for events and transfers: */
382 dbc->ring_evt = xhci_ring_alloc(xhci, 1, 1, TYPE_EVENT, 0, flags);
383 if (!dbc->ring_evt)
384 goto evt_fail;
386 dbc->ring_in = xhci_ring_alloc(xhci, 1, 1, TYPE_BULK, 0, flags);
387 if (!dbc->ring_in)
388 goto in_fail;
390 dbc->ring_out = xhci_ring_alloc(xhci, 1, 1, TYPE_BULK, 0, flags);
391 if (!dbc->ring_out)
392 goto out_fail;
394 /* Allocate and populate ERST: */
395 ret = xhci_alloc_erst(xhci, dbc->ring_evt, &dbc->erst, flags);
396 if (ret)
397 goto erst_fail;
399 /* Allocate context data structure: */
400 dbc->ctx = xhci_alloc_container_ctx(xhci, XHCI_CTX_TYPE_DEVICE, flags);
401 if (!dbc->ctx)
402 goto ctx_fail;
404 /* Allocate the string table: */
405 dbc->string_size = sizeof(struct dbc_str_descs);
406 dbc->string = dbc_dma_alloc_coherent(xhci,
407 dbc->string_size,
408 &dbc->string_dma,
409 flags);
410 if (!dbc->string)
411 goto string_fail;
413 /* Setup ERST register: */
414 writel(dbc->erst.erst_size, &dbc->regs->ersts);
415 xhci_write_64(xhci, dbc->erst.erst_dma_addr, &dbc->regs->erstba);
416 deq = xhci_trb_virt_to_dma(dbc->ring_evt->deq_seg,
417 dbc->ring_evt->dequeue);
418 xhci_write_64(xhci, deq, &dbc->regs->erdp);
420 /* Setup strings and contexts: */
421 string_length = xhci_dbc_populate_strings(dbc->string);
422 xhci_dbc_init_contexts(xhci, string_length);
424 mmiowb();
426 xhci_dbc_eps_init(xhci);
427 dbc->state = DS_INITIALIZED;
429 return 0;
431 string_fail:
432 xhci_free_container_ctx(xhci, dbc->ctx);
433 dbc->ctx = NULL;
434 ctx_fail:
435 xhci_free_erst(xhci, &dbc->erst);
436 erst_fail:
437 xhci_ring_free(xhci, dbc->ring_out);
438 dbc->ring_out = NULL;
439 out_fail:
440 xhci_ring_free(xhci, dbc->ring_in);
441 dbc->ring_in = NULL;
442 in_fail:
443 xhci_ring_free(xhci, dbc->ring_evt);
444 dbc->ring_evt = NULL;
445 evt_fail:
446 return -ENOMEM;
449 static void xhci_dbc_mem_cleanup(struct xhci_hcd *xhci)
451 struct xhci_dbc *dbc = xhci->dbc;
453 if (!dbc)
454 return;
456 xhci_dbc_eps_exit(xhci);
458 if (dbc->string) {
459 dbc_dma_free_coherent(xhci,
460 dbc->string_size,
461 dbc->string, dbc->string_dma);
462 dbc->string = NULL;
465 xhci_free_container_ctx(xhci, dbc->ctx);
466 dbc->ctx = NULL;
468 xhci_free_erst(xhci, &dbc->erst);
469 xhci_ring_free(xhci, dbc->ring_out);
470 xhci_ring_free(xhci, dbc->ring_in);
471 xhci_ring_free(xhci, dbc->ring_evt);
472 dbc->ring_in = NULL;
473 dbc->ring_out = NULL;
474 dbc->ring_evt = NULL;
477 static int xhci_do_dbc_start(struct xhci_hcd *xhci)
479 int ret;
480 u32 ctrl;
481 struct xhci_dbc *dbc = xhci->dbc;
483 if (dbc->state != DS_DISABLED)
484 return -EINVAL;
486 writel(0, &dbc->regs->control);
487 ret = xhci_handshake(&dbc->regs->control,
488 DBC_CTRL_DBC_ENABLE,
489 0, 1000);
490 if (ret)
491 return ret;
493 ret = xhci_dbc_mem_init(xhci, GFP_ATOMIC);
494 if (ret)
495 return ret;
497 ctrl = readl(&dbc->regs->control);
498 writel(ctrl | DBC_CTRL_DBC_ENABLE | DBC_CTRL_PORT_ENABLE,
499 &dbc->regs->control);
500 ret = xhci_handshake(&dbc->regs->control,
501 DBC_CTRL_DBC_ENABLE,
502 DBC_CTRL_DBC_ENABLE, 1000);
503 if (ret)
504 return ret;
506 dbc->state = DS_ENABLED;
508 return 0;
511 static int xhci_do_dbc_stop(struct xhci_hcd *xhci)
513 struct xhci_dbc *dbc = xhci->dbc;
515 if (dbc->state == DS_DISABLED)
516 return -1;
518 writel(0, &dbc->regs->control);
519 xhci_dbc_mem_cleanup(xhci);
520 dbc->state = DS_DISABLED;
522 return 0;
525 static int xhci_dbc_start(struct xhci_hcd *xhci)
527 int ret;
528 unsigned long flags;
529 struct xhci_dbc *dbc = xhci->dbc;
531 WARN_ON(!dbc);
533 pm_runtime_get_sync(xhci_to_hcd(xhci)->self.controller);
535 spin_lock_irqsave(&dbc->lock, flags);
536 ret = xhci_do_dbc_start(xhci);
537 spin_unlock_irqrestore(&dbc->lock, flags);
539 if (ret) {
540 pm_runtime_put(xhci_to_hcd(xhci)->self.controller);
541 return ret;
544 return mod_delayed_work(system_wq, &dbc->event_work, 1);
547 static void xhci_dbc_stop(struct xhci_hcd *xhci)
549 int ret;
550 unsigned long flags;
551 struct xhci_dbc *dbc = xhci->dbc;
552 struct dbc_port *port = &dbc->port;
554 WARN_ON(!dbc);
556 cancel_delayed_work_sync(&dbc->event_work);
558 if (port->registered)
559 xhci_dbc_tty_unregister_device(xhci);
561 spin_lock_irqsave(&dbc->lock, flags);
562 ret = xhci_do_dbc_stop(xhci);
563 spin_unlock_irqrestore(&dbc->lock, flags);
565 if (!ret)
566 pm_runtime_put_sync(xhci_to_hcd(xhci)->self.controller);
569 static void
570 dbc_handle_port_status(struct xhci_hcd *xhci, union xhci_trb *event)
572 u32 portsc;
573 struct xhci_dbc *dbc = xhci->dbc;
575 portsc = readl(&dbc->regs->portsc);
576 if (portsc & DBC_PORTSC_CONN_CHANGE)
577 xhci_info(xhci, "DbC port connect change\n");
579 if (portsc & DBC_PORTSC_RESET_CHANGE)
580 xhci_info(xhci, "DbC port reset change\n");
582 if (portsc & DBC_PORTSC_LINK_CHANGE)
583 xhci_info(xhci, "DbC port link status change\n");
585 if (portsc & DBC_PORTSC_CONFIG_CHANGE)
586 xhci_info(xhci, "DbC config error change\n");
588 /* Port reset change bit will be cleared in other place: */
589 writel(portsc & ~DBC_PORTSC_RESET_CHANGE, &dbc->regs->portsc);
592 static void dbc_handle_xfer_event(struct xhci_hcd *xhci, union xhci_trb *event)
594 struct dbc_ep *dep;
595 struct xhci_ring *ring;
596 int ep_id;
597 int status;
598 u32 comp_code;
599 size_t remain_length;
600 struct dbc_request *req = NULL, *r;
602 comp_code = GET_COMP_CODE(le32_to_cpu(event->generic.field[2]));
603 remain_length = EVENT_TRB_LEN(le32_to_cpu(event->generic.field[2]));
604 ep_id = TRB_TO_EP_ID(le32_to_cpu(event->generic.field[3]));
605 dep = (ep_id == EPID_OUT) ?
606 get_out_ep(xhci) : get_in_ep(xhci);
607 ring = dep->ring;
609 switch (comp_code) {
610 case COMP_SUCCESS:
611 remain_length = 0;
612 /* FALLTHROUGH */
613 case COMP_SHORT_PACKET:
614 status = 0;
615 break;
616 case COMP_TRB_ERROR:
617 case COMP_BABBLE_DETECTED_ERROR:
618 case COMP_USB_TRANSACTION_ERROR:
619 case COMP_STALL_ERROR:
620 xhci_warn(xhci, "tx error %d detected\n", comp_code);
621 status = -comp_code;
622 break;
623 default:
624 xhci_err(xhci, "unknown tx error %d\n", comp_code);
625 status = -comp_code;
626 break;
629 /* Match the pending request: */
630 list_for_each_entry(r, &dep->list_pending, list_pending) {
631 if (r->trb_dma == event->trans_event.buffer) {
632 req = r;
633 break;
637 if (!req) {
638 xhci_warn(xhci, "no matched request\n");
639 return;
642 trace_xhci_dbc_handle_transfer(ring, &req->trb->generic);
644 ring->num_trbs_free++;
645 req->actual = req->length - remain_length;
646 xhci_dbc_giveback(req, status);
649 static enum evtreturn xhci_dbc_do_handle_events(struct xhci_dbc *dbc)
651 dma_addr_t deq;
652 struct dbc_ep *dep;
653 union xhci_trb *evt;
654 u32 ctrl, portsc;
655 struct xhci_hcd *xhci = dbc->xhci;
656 bool update_erdp = false;
658 /* DbC state machine: */
659 switch (dbc->state) {
660 case DS_DISABLED:
661 case DS_INITIALIZED:
663 return EVT_ERR;
664 case DS_ENABLED:
665 portsc = readl(&dbc->regs->portsc);
666 if (portsc & DBC_PORTSC_CONN_STATUS) {
667 dbc->state = DS_CONNECTED;
668 xhci_info(xhci, "DbC connected\n");
671 return EVT_DONE;
672 case DS_CONNECTED:
673 ctrl = readl(&dbc->regs->control);
674 if (ctrl & DBC_CTRL_DBC_RUN) {
675 dbc->state = DS_CONFIGURED;
676 xhci_info(xhci, "DbC configured\n");
677 portsc = readl(&dbc->regs->portsc);
678 writel(portsc, &dbc->regs->portsc);
679 return EVT_GSER;
682 return EVT_DONE;
683 case DS_CONFIGURED:
684 /* Handle cable unplug event: */
685 portsc = readl(&dbc->regs->portsc);
686 if (!(portsc & DBC_PORTSC_PORT_ENABLED) &&
687 !(portsc & DBC_PORTSC_CONN_STATUS)) {
688 xhci_info(xhci, "DbC cable unplugged\n");
689 dbc->state = DS_ENABLED;
690 xhci_dbc_flush_requests(dbc);
692 return EVT_DISC;
695 /* Handle debug port reset event: */
696 if (portsc & DBC_PORTSC_RESET_CHANGE) {
697 xhci_info(xhci, "DbC port reset\n");
698 writel(portsc, &dbc->regs->portsc);
699 dbc->state = DS_ENABLED;
700 xhci_dbc_flush_requests(dbc);
702 return EVT_DISC;
705 /* Handle endpoint stall event: */
706 ctrl = readl(&dbc->regs->control);
707 if ((ctrl & DBC_CTRL_HALT_IN_TR) ||
708 (ctrl & DBC_CTRL_HALT_OUT_TR)) {
709 xhci_info(xhci, "DbC Endpoint stall\n");
710 dbc->state = DS_STALLED;
712 if (ctrl & DBC_CTRL_HALT_IN_TR) {
713 dep = get_in_ep(xhci);
714 xhci_dbc_flush_endpoint_requests(dep);
717 if (ctrl & DBC_CTRL_HALT_OUT_TR) {
718 dep = get_out_ep(xhci);
719 xhci_dbc_flush_endpoint_requests(dep);
722 return EVT_DONE;
725 /* Clear DbC run change bit: */
726 if (ctrl & DBC_CTRL_DBC_RUN_CHANGE) {
727 writel(ctrl, &dbc->regs->control);
728 ctrl = readl(&dbc->regs->control);
731 break;
732 case DS_STALLED:
733 ctrl = readl(&dbc->regs->control);
734 if (!(ctrl & DBC_CTRL_HALT_IN_TR) &&
735 !(ctrl & DBC_CTRL_HALT_OUT_TR) &&
736 (ctrl & DBC_CTRL_DBC_RUN)) {
737 dbc->state = DS_CONFIGURED;
738 break;
741 return EVT_DONE;
742 default:
743 xhci_err(xhci, "Unknown DbC state %d\n", dbc->state);
744 break;
747 /* Handle the events in the event ring: */
748 evt = dbc->ring_evt->dequeue;
749 while ((le32_to_cpu(evt->event_cmd.flags) & TRB_CYCLE) ==
750 dbc->ring_evt->cycle_state) {
752 * Add a barrier between reading the cycle flag and any
753 * reads of the event's flags/data below:
755 rmb();
757 trace_xhci_dbc_handle_event(dbc->ring_evt, &evt->generic);
759 switch (le32_to_cpu(evt->event_cmd.flags) & TRB_TYPE_BITMASK) {
760 case TRB_TYPE(TRB_PORT_STATUS):
761 dbc_handle_port_status(xhci, evt);
762 break;
763 case TRB_TYPE(TRB_TRANSFER):
764 dbc_handle_xfer_event(xhci, evt);
765 break;
766 default:
767 break;
770 inc_deq(xhci, dbc->ring_evt);
771 evt = dbc->ring_evt->dequeue;
772 update_erdp = true;
775 /* Update event ring dequeue pointer: */
776 if (update_erdp) {
777 deq = xhci_trb_virt_to_dma(dbc->ring_evt->deq_seg,
778 dbc->ring_evt->dequeue);
779 xhci_write_64(xhci, deq, &dbc->regs->erdp);
782 return EVT_DONE;
785 static void xhci_dbc_handle_events(struct work_struct *work)
787 int ret;
788 enum evtreturn evtr;
789 struct xhci_dbc *dbc;
790 unsigned long flags;
791 struct xhci_hcd *xhci;
793 dbc = container_of(to_delayed_work(work), struct xhci_dbc, event_work);
794 xhci = dbc->xhci;
796 spin_lock_irqsave(&dbc->lock, flags);
797 evtr = xhci_dbc_do_handle_events(dbc);
798 spin_unlock_irqrestore(&dbc->lock, flags);
800 switch (evtr) {
801 case EVT_GSER:
802 ret = xhci_dbc_tty_register_device(xhci);
803 if (ret) {
804 xhci_err(xhci, "failed to alloc tty device\n");
805 break;
808 xhci_info(xhci, "DbC now attached to /dev/ttyDBC0\n");
809 break;
810 case EVT_DISC:
811 xhci_dbc_tty_unregister_device(xhci);
812 break;
813 case EVT_DONE:
814 break;
815 default:
816 xhci_info(xhci, "stop handling dbc events\n");
817 return;
820 mod_delayed_work(system_wq, &dbc->event_work, 1);
823 static void xhci_do_dbc_exit(struct xhci_hcd *xhci)
825 unsigned long flags;
827 spin_lock_irqsave(&xhci->lock, flags);
828 kfree(xhci->dbc);
829 xhci->dbc = NULL;
830 spin_unlock_irqrestore(&xhci->lock, flags);
833 static int xhci_do_dbc_init(struct xhci_hcd *xhci)
835 u32 reg;
836 struct xhci_dbc *dbc;
837 unsigned long flags;
838 void __iomem *base;
839 int dbc_cap_offs;
841 base = &xhci->cap_regs->hc_capbase;
842 dbc_cap_offs = xhci_find_next_ext_cap(base, 0, XHCI_EXT_CAPS_DEBUG);
843 if (!dbc_cap_offs)
844 return -ENODEV;
846 dbc = kzalloc(sizeof(*dbc), GFP_KERNEL);
847 if (!dbc)
848 return -ENOMEM;
850 dbc->regs = base + dbc_cap_offs;
852 /* We will avoid using DbC in xhci driver if it's in use. */
853 reg = readl(&dbc->regs->control);
854 if (reg & DBC_CTRL_DBC_ENABLE) {
855 kfree(dbc);
856 return -EBUSY;
859 spin_lock_irqsave(&xhci->lock, flags);
860 if (xhci->dbc) {
861 spin_unlock_irqrestore(&xhci->lock, flags);
862 kfree(dbc);
863 return -EBUSY;
865 xhci->dbc = dbc;
866 spin_unlock_irqrestore(&xhci->lock, flags);
868 dbc->xhci = xhci;
869 INIT_DELAYED_WORK(&dbc->event_work, xhci_dbc_handle_events);
870 spin_lock_init(&dbc->lock);
872 return 0;
875 static ssize_t dbc_show(struct device *dev,
876 struct device_attribute *attr,
877 char *buf)
879 const char *p;
880 struct xhci_dbc *dbc;
881 struct xhci_hcd *xhci;
883 xhci = hcd_to_xhci(dev_get_drvdata(dev));
884 dbc = xhci->dbc;
886 switch (dbc->state) {
887 case DS_DISABLED:
888 p = "disabled";
889 break;
890 case DS_INITIALIZED:
891 p = "initialized";
892 break;
893 case DS_ENABLED:
894 p = "enabled";
895 break;
896 case DS_CONNECTED:
897 p = "connected";
898 break;
899 case DS_CONFIGURED:
900 p = "configured";
901 break;
902 case DS_STALLED:
903 p = "stalled";
904 break;
905 default:
906 p = "unknown";
909 return sprintf(buf, "%s\n", p);
912 static ssize_t dbc_store(struct device *dev,
913 struct device_attribute *attr,
914 const char *buf, size_t count)
916 struct xhci_hcd *xhci;
918 xhci = hcd_to_xhci(dev_get_drvdata(dev));
920 if (!strncmp(buf, "enable", 6))
921 xhci_dbc_start(xhci);
922 else if (!strncmp(buf, "disable", 7))
923 xhci_dbc_stop(xhci);
924 else
925 return -EINVAL;
927 return count;
930 static DEVICE_ATTR_RW(dbc);
932 int xhci_dbc_init(struct xhci_hcd *xhci)
934 int ret;
935 struct device *dev = xhci_to_hcd(xhci)->self.controller;
937 ret = xhci_do_dbc_init(xhci);
938 if (ret)
939 goto init_err3;
941 ret = xhci_dbc_tty_register_driver(xhci);
942 if (ret)
943 goto init_err2;
945 ret = device_create_file(dev, &dev_attr_dbc);
946 if (ret)
947 goto init_err1;
949 return 0;
951 init_err1:
952 xhci_dbc_tty_unregister_driver();
953 init_err2:
954 xhci_do_dbc_exit(xhci);
955 init_err3:
956 return ret;
959 void xhci_dbc_exit(struct xhci_hcd *xhci)
961 struct device *dev = xhci_to_hcd(xhci)->self.controller;
963 if (!xhci->dbc)
964 return;
966 device_remove_file(dev, &dev_attr_dbc);
967 xhci_dbc_tty_unregister_driver();
968 xhci_dbc_stop(xhci);
969 xhci_do_dbc_exit(xhci);
972 #ifdef CONFIG_PM
973 int xhci_dbc_suspend(struct xhci_hcd *xhci)
975 struct xhci_dbc *dbc = xhci->dbc;
977 if (!dbc)
978 return 0;
980 if (dbc->state == DS_CONFIGURED)
981 dbc->resume_required = 1;
983 xhci_dbc_stop(xhci);
985 return 0;
988 int xhci_dbc_resume(struct xhci_hcd *xhci)
990 int ret = 0;
991 struct xhci_dbc *dbc = xhci->dbc;
993 if (!dbc)
994 return 0;
996 if (dbc->resume_required) {
997 dbc->resume_required = 0;
998 xhci_dbc_start(xhci);
1001 return ret;
1003 #endif /* CONFIG_PM */