1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * c67x00-sched.c: Cypress C67X00 USB Host Controller Driver - TD scheduling
4 *
5 * Copyright (C) 2006-2008 Barco N.V.
6 * Derived from the Cypress cy7c67200/300 ezusb linux driver and
7 * based on multiple host controller drivers inside the linux kernel.
8 */
9
10#include <linux/kthread.h>
11#include <linux/slab.h>
12
13#include "c67x00.h"
14#include "c67x00-hcd.h"
15
16/*
17 * These are the stages for a control urb, they are kept
18 * in both urb->interval and td->privdata.
19 */
20#define SETUP_STAGE 0
21#define DATA_STAGE 1
22#define STATUS_STAGE 2
23
24/* -------------------------------------------------------------------------- */
25
26/*
27 * struct c67x00_ep_data: Host endpoint data structure
28 */
29struct c67x00_ep_data {
30 struct list_head queue;
31 struct list_head node;
32 struct usb_host_endpoint *hep;
33 struct usb_device *dev;
34 u16 next_frame; /* For int/isoc transactions */
35};
36
37/*
38 * struct c67x00_td
39 *
40 * Hardware parts are little endiannes, SW in CPU endianess.
41 */
42struct c67x00_td {
43 /* HW specific part */
44 __le16 ly_base_addr; /* Bytes 0-1 */
45 __le16 port_length; /* Bytes 2-3 */
46 u8 pid_ep; /* Byte 4 */
47 u8 dev_addr; /* Byte 5 */
48 u8 ctrl_reg; /* Byte 6 */
49 u8 status; /* Byte 7 */
50 u8 retry_cnt; /* Byte 8 */
51#define TT_OFFSET 2
52#define TT_CONTROL 0
53#define TT_ISOCHRONOUS 1
54#define TT_BULK 2
55#define TT_INTERRUPT 3
56 u8 residue; /* Byte 9 */
57 __le16 next_td_addr; /* Bytes 10-11 */
58 /* SW part */
59 struct list_head td_list;
60 u16 td_addr;
61 void *data;
62 struct urb *urb;
63 unsigned long privdata;
64
65 /* These are needed for handling the toggle bits:
66 * an urb can be dequeued while a td is in progress
67 * after checking the td, the toggle bit might need to
68 * be fixed */
69 struct c67x00_ep_data *ep_data;
70 unsigned int pipe;
71};
72
73struct c67x00_urb_priv {
74 struct list_head hep_node;
75 struct urb *urb;
76 int port;
77 int cnt; /* packet number for isoc */
78 int status;
79 struct c67x00_ep_data *ep_data;
80};
81
82#define td_udev(td) ((td)->ep_data->dev)
83
84#define CY_TD_SIZE 12
85
86#define TD_PIDEP_OFFSET 0x04
87#define TD_PIDEPMASK_PID 0xF0
88#define TD_PIDEPMASK_EP 0x0F
89#define TD_PORTLENMASK_DL 0x03FF
90#define TD_PORTLENMASK_PN 0xC000
91
92#define TD_STATUS_OFFSET 0x07
93#define TD_STATUSMASK_ACK 0x01
94#define TD_STATUSMASK_ERR 0x02
95#define TD_STATUSMASK_TMOUT 0x04
96#define TD_STATUSMASK_SEQ 0x08
97#define TD_STATUSMASK_SETUP 0x10
98#define TD_STATUSMASK_OVF 0x20
99#define TD_STATUSMASK_NAK 0x40
100#define TD_STATUSMASK_STALL 0x80
101
102#define TD_ERROR_MASK (TD_STATUSMASK_ERR | TD_STATUSMASK_TMOUT | \
103 TD_STATUSMASK_STALL)
104
105#define TD_RETRYCNT_OFFSET 0x08
106#define TD_RETRYCNTMASK_ACT_FLG 0x10
107#define TD_RETRYCNTMASK_TX_TYPE 0x0C
108#define TD_RETRYCNTMASK_RTY_CNT 0x03
109
110#define TD_RESIDUE_OVERFLOW 0x80
111
112#define TD_PID_IN 0x90
113
114/* Residue: signed 8bits, neg -> OVERFLOW, pos -> UNDERFLOW */
115#define td_residue(td) ((__s8)(td->residue))
116#define td_ly_base_addr(td) (__le16_to_cpu((td)->ly_base_addr))
117#define td_port_length(td) (__le16_to_cpu((td)->port_length))
118#define td_next_td_addr(td) (__le16_to_cpu((td)->next_td_addr))
119
120#define td_active(td) ((td)->retry_cnt & TD_RETRYCNTMASK_ACT_FLG)
121#define td_length(td) (td_port_length(td) & TD_PORTLENMASK_DL)
122
123#define td_sequence_ok(td) (!td->status || \
124 (!(td->status & TD_STATUSMASK_SEQ) == \
125 !(td->ctrl_reg & SEQ_SEL)))
126
127#define td_acked(td) (!td->status || \
128 (td->status & TD_STATUSMASK_ACK))
129#define td_actual_bytes(td) (td_length(td) - td_residue(td))
130
131/* -------------------------------------------------------------------------- */
132
133/*
134 * dbg_td - Dump the contents of the TD
135 */
136static void dbg_td(struct c67x00_hcd *c67x00, struct c67x00_td *td, char *msg)
137{
138 struct device *dev = c67x00_hcd_dev(c67x00);
139
140 dev_dbg(dev, "### %s at 0x%04x\n", msg, td->td_addr);
141 dev_dbg(dev, "urb: 0x%p\n", td->urb);
142 dev_dbg(dev, "endpoint: %4d\n", usb_pipeendpoint(td->pipe));
143 dev_dbg(dev, "pipeout: %4d\n", usb_pipeout(td->pipe));
144 dev_dbg(dev, "ly_base_addr: 0x%04x\n", td_ly_base_addr(td));
145 dev_dbg(dev, "port_length: 0x%04x\n", td_port_length(td));
146 dev_dbg(dev, "pid_ep: 0x%02x\n", td->pid_ep);
147 dev_dbg(dev, "dev_addr: 0x%02x\n", td->dev_addr);
148 dev_dbg(dev, "ctrl_reg: 0x%02x\n", td->ctrl_reg);
149 dev_dbg(dev, "status: 0x%02x\n", td->status);
150 dev_dbg(dev, "retry_cnt: 0x%02x\n", td->retry_cnt);
151 dev_dbg(dev, "residue: 0x%02x\n", td->residue);
152 dev_dbg(dev, "next_td_addr: 0x%04x\n", td_next_td_addr(td));
153 dev_dbg(dev, "data: %*ph\n", td_length(td), td->data);
154}
155
156/* -------------------------------------------------------------------------- */
157/* Helper functions */
158
159static inline u16 c67x00_get_current_frame_number(struct c67x00_hcd *c67x00)
160{
161 return c67x00_ll_husb_get_frame(sie: c67x00->sie) & HOST_FRAME_MASK;
162}
163
164/*
165 * frame_add
166 * Software wraparound for framenumbers.
167 */
168static inline u16 frame_add(u16 a, u16 b)
169{
170 return (a + b) & HOST_FRAME_MASK;
171}
172
173/*
174 * frame_after - is frame a after frame b
175 */
176static inline int frame_after(u16 a, u16 b)
177{
178 return ((HOST_FRAME_MASK + a - b) & HOST_FRAME_MASK) <
179 (HOST_FRAME_MASK / 2);
180}
181
182/*
183 * frame_after_eq - is frame a after or equal to frame b
184 */
185static inline int frame_after_eq(u16 a, u16 b)
186{
187 return ((HOST_FRAME_MASK + 1 + a - b) & HOST_FRAME_MASK) <
188 (HOST_FRAME_MASK / 2);
189}
190
191/* -------------------------------------------------------------------------- */
192
193/*
194 * c67x00_release_urb - remove link from all tds to this urb
195 * Disconnects the urb from it's tds, so that it can be given back.
196 * pre: urb->hcpriv != NULL
197 */
198static void c67x00_release_urb(struct c67x00_hcd *c67x00, struct urb *urb)
199{
200 struct c67x00_td *td;
201 struct c67x00_urb_priv *urbp;
202
203 BUG_ON(!urb);
204
205 c67x00->urb_count--;
206
207 if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) {
208 c67x00->urb_iso_count--;
209 if (c67x00->urb_iso_count == 0)
210 c67x00->max_frame_bw = MAX_FRAME_BW_STD;
211 }
212
213 /* TODO this might be not so efficient when we've got many urbs!
214 * Alternatives:
215 * * only clear when needed
216 * * keep a list of tds with each urbp
217 */
218 list_for_each_entry(td, &c67x00->td_list, td_list)
219 if (urb == td->urb)
220 td->urb = NULL;
221
222 urbp = urb->hcpriv;
223 urb->hcpriv = NULL;
224 list_del(entry: &urbp->hep_node);
225 kfree(objp: urbp);
226}
227
228/* -------------------------------------------------------------------------- */
229
230static struct c67x00_ep_data *
231c67x00_ep_data_alloc(struct c67x00_hcd *c67x00, struct urb *urb)
232{
233 struct usb_host_endpoint *hep = urb->ep;
234 struct c67x00_ep_data *ep_data;
235 int type;
236
237 c67x00->current_frame = c67x00_get_current_frame_number(c67x00);
238
239 /* Check if endpoint already has a c67x00_ep_data struct allocated */
240 if (hep->hcpriv) {
241 ep_data = hep->hcpriv;
242 if (frame_after(a: c67x00->current_frame, b: ep_data->next_frame))
243 ep_data->next_frame =
244 frame_add(a: c67x00->current_frame, b: 1);
245 return hep->hcpriv;
246 }
247
248 /* Allocate and initialize a new c67x00 endpoint data structure */
249 ep_data = kzalloc(size: sizeof(*ep_data), GFP_ATOMIC);
250 if (!ep_data)
251 return NULL;
252
253 INIT_LIST_HEAD(list: &ep_data->queue);
254 INIT_LIST_HEAD(list: &ep_data->node);
255 ep_data->hep = hep;
256
257 /* hold a reference to udev as long as this endpoint lives,
258 * this is needed to possibly fix the data toggle */
259 ep_data->dev = usb_get_dev(dev: urb->dev);
260 hep->hcpriv = ep_data;
261
262 /* For ISOC and INT endpoints, start ASAP: */
263 ep_data->next_frame = frame_add(a: c67x00->current_frame, b: 1);
264
265 /* Add the endpoint data to one of the pipe lists; must be added
266 in order of endpoint address */
267 type = usb_pipetype(urb->pipe);
268 if (list_empty(head: &ep_data->node)) {
269 list_add(new: &ep_data->node, head: &c67x00->list[type]);
270 } else {
271 struct c67x00_ep_data *prev;
272
273 list_for_each_entry(prev, &c67x00->list[type], node) {
274 if (prev->hep->desc.bEndpointAddress >
275 hep->desc.bEndpointAddress) {
276 list_add(new: &ep_data->node, head: prev->node.prev);
277 break;
278 }
279 }
280 }
281
282 return ep_data;
283}
284
285static int c67x00_ep_data_free(struct usb_host_endpoint *hep)
286{
287 struct c67x00_ep_data *ep_data = hep->hcpriv;
288
289 if (!ep_data)
290 return 0;
291
292 if (!list_empty(head: &ep_data->queue))
293 return -EBUSY;
294
295 usb_put_dev(dev: ep_data->dev);
296 list_del(entry: &ep_data->queue);
297 list_del(entry: &ep_data->node);
298
299 kfree(objp: ep_data);
300 hep->hcpriv = NULL;
301
302 return 0;
303}
304
305void c67x00_endpoint_disable(struct usb_hcd *hcd, struct usb_host_endpoint *ep)
306{
307 struct c67x00_hcd *c67x00 = hcd_to_c67x00_hcd(hcd);
308 unsigned long flags;
309
310 if (!list_empty(head: &ep->urb_list))
311 dev_warn(c67x00_hcd_dev(c67x00), "error: urb list not empty\n");
312
313 spin_lock_irqsave(&c67x00->lock, flags);
314
315 /* loop waiting for all transfers in the endpoint queue to complete */
316 while (c67x00_ep_data_free(hep: ep)) {
317 /* Drop the lock so we can sleep waiting for the hardware */
318 spin_unlock_irqrestore(lock: &c67x00->lock, flags);
319
320 /* it could happen that we reinitialize this completion, while
321 * somebody was waiting for that completion. The timeout and
322 * while loop handle such cases, but this might be improved */
323 reinit_completion(x: &c67x00->endpoint_disable);
324 c67x00_sched_kick(c67x00);
325 wait_for_completion_timeout(x: &c67x00->endpoint_disable, timeout: 1 * HZ);
326
327 spin_lock_irqsave(&c67x00->lock, flags);
328 }
329
330 spin_unlock_irqrestore(lock: &c67x00->lock, flags);
331}
332
333/* -------------------------------------------------------------------------- */
334
335static inline int get_root_port(struct usb_device *dev)
336{
337 while (dev->parent->parent)
338 dev = dev->parent;
339 return dev->portnum;
340}
341
342int c67x00_urb_enqueue(struct usb_hcd *hcd,
343 struct urb *urb, gfp_t mem_flags)
344{
345 int ret;
346 unsigned long flags;
347 struct c67x00_urb_priv *urbp;
348 struct c67x00_hcd *c67x00 = hcd_to_c67x00_hcd(hcd);
349 int port = get_root_port(dev: urb->dev)-1;
350
351 /* Allocate and initialize urb private data */
352 urbp = kzalloc(size: sizeof(*urbp), flags: mem_flags);
353 if (!urbp) {
354 ret = -ENOMEM;
355 goto err_urbp;
356 }
357
358 spin_lock_irqsave(&c67x00->lock, flags);
359
360 /* Make sure host controller is running */
361 if (!HC_IS_RUNNING(hcd->state)) {
362 ret = -ENODEV;
363 goto err_not_linked;
364 }
365
366 ret = usb_hcd_link_urb_to_ep(hcd, urb);
367 if (ret)
368 goto err_not_linked;
369
370 INIT_LIST_HEAD(list: &urbp->hep_node);
371 urbp->urb = urb;
372 urbp->port = port;
373
374 urbp->ep_data = c67x00_ep_data_alloc(c67x00, urb);
375
376 if (!urbp->ep_data) {
377 ret = -ENOMEM;
378 goto err_epdata;
379 }
380
381 /* TODO claim bandwidth with usb_claim_bandwidth?
382 * also release it somewhere! */
383
384 urb->hcpriv = urbp;
385
386 urb->actual_length = 0; /* Nothing received/transmitted yet */
387
388 switch (usb_pipetype(urb->pipe)) {
389 case PIPE_CONTROL:
390 urb->interval = SETUP_STAGE;
391 break;
392 case PIPE_INTERRUPT:
393 break;
394 case PIPE_BULK:
395 break;
396 case PIPE_ISOCHRONOUS:
397 if (c67x00->urb_iso_count == 0)
398 c67x00->max_frame_bw = MAX_FRAME_BW_ISO;
399 c67x00->urb_iso_count++;
400 /* Assume always URB_ISO_ASAP, FIXME */
401 if (list_empty(head: &urbp->ep_data->queue))
402 urb->start_frame = urbp->ep_data->next_frame;
403 else {
404 /* Go right after the last one */
405 struct urb *last_urb;
406
407 last_urb = list_entry(urbp->ep_data->queue.prev,
408 struct c67x00_urb_priv,
409 hep_node)->urb;
410 urb->start_frame =
411 frame_add(a: last_urb->start_frame,
412 b: last_urb->number_of_packets *
413 last_urb->interval);
414 }
415 urbp->cnt = 0;
416 break;
417 }
418
419 /* Add the URB to the endpoint queue */
420 list_add_tail(new: &urbp->hep_node, head: &urbp->ep_data->queue);
421
422 /* If this is the only URB, kick start the controller */
423 if (!c67x00->urb_count++)
424 c67x00_ll_hpi_enable_sofeop(sie: c67x00->sie);
425
426 c67x00_sched_kick(c67x00);
427 spin_unlock_irqrestore(lock: &c67x00->lock, flags);
428
429 return 0;
430
431err_epdata:
432 usb_hcd_unlink_urb_from_ep(hcd, urb);
433err_not_linked:
434 spin_unlock_irqrestore(lock: &c67x00->lock, flags);
435 kfree(objp: urbp);
436err_urbp:
437
438 return ret;
439}
440
441int c67x00_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
442{
443 struct c67x00_hcd *c67x00 = hcd_to_c67x00_hcd(hcd);
444 unsigned long flags;
445 int rc;
446
447 spin_lock_irqsave(&c67x00->lock, flags);
448 rc = usb_hcd_check_unlink_urb(hcd, urb, status);
449 if (rc)
450 goto done;
451
452 c67x00_release_urb(c67x00, urb);
453 usb_hcd_unlink_urb_from_ep(hcd, urb);
454
455 spin_unlock(lock: &c67x00->lock);
456 usb_hcd_giveback_urb(hcd, urb, status);
457 spin_lock(lock: &c67x00->lock);
458
459 spin_unlock_irqrestore(lock: &c67x00->lock, flags);
460
461 return 0;
462
463 done:
464 spin_unlock_irqrestore(lock: &c67x00->lock, flags);
465 return rc;
466}
467
468/* -------------------------------------------------------------------------- */
469
470/*
471 * pre: c67x00 locked, urb unlocked
472 */
473static void
474c67x00_giveback_urb(struct c67x00_hcd *c67x00, struct urb *urb, int status)
475{
476 struct c67x00_urb_priv *urbp;
477
478 if (!urb)
479 return;
480
481 urbp = urb->hcpriv;
482 urbp->status = status;
483
484 list_del_init(entry: &urbp->hep_node);
485
486 c67x00_release_urb(c67x00, urb);
487 usb_hcd_unlink_urb_from_ep(hcd: c67x00_hcd_to_hcd(c67x00), urb);
488 spin_unlock(lock: &c67x00->lock);
489 usb_hcd_giveback_urb(hcd: c67x00_hcd_to_hcd(c67x00), urb, status);
490 spin_lock(lock: &c67x00->lock);
491}
492
493/* -------------------------------------------------------------------------- */
494
495static int c67x00_claim_frame_bw(struct c67x00_hcd *c67x00, struct urb *urb,
496 int len, int periodic)
497{
498 struct c67x00_urb_priv *urbp = urb->hcpriv;
499 int bit_time;
500
501 /* According to the C67x00 BIOS user manual, page 3-18,19, the
502 * following calculations provide the full speed bit times for
503 * a transaction.
504 *
505 * FS(in) = 112.5 + 9.36*BC + HOST_DELAY
506 * FS(in,iso) = 90.5 + 9.36*BC + HOST_DELAY
507 * FS(out) = 112.5 + 9.36*BC + HOST_DELAY
508 * FS(out,iso) = 78.4 + 9.36*BC + HOST_DELAY
509 * LS(in) = 802.4 + 75.78*BC + HOST_DELAY
510 * LS(out) = 802.6 + 74.67*BC + HOST_DELAY
511 *
512 * HOST_DELAY == 106 for the c67200 and c67300.
513 */
514
515 /* make calculations in 1/100 bit times to maintain resolution */
516 if (urbp->ep_data->dev->speed == USB_SPEED_LOW) {
517 /* Low speed pipe */
518 if (usb_pipein(urb->pipe))
519 bit_time = 80240 + 7578*len;
520 else
521 bit_time = 80260 + 7467*len;
522 } else {
523 /* FS pipes */
524 if (usb_pipeisoc(urb->pipe))
525 bit_time = usb_pipein(urb->pipe) ? 9050 : 7840;
526 else
527 bit_time = 11250;
528 bit_time += 936*len;
529 }
530
531 /* Scale back down to integer bit times. Use a host delay of 106.
532 * (this is the only place it is used) */
533 bit_time = ((bit_time+50) / 100) + 106;
534
535 if (unlikely(bit_time + c67x00->bandwidth_allocated >=
536 c67x00->max_frame_bw))
537 return -EMSGSIZE;
538
539 if (unlikely(c67x00->next_td_addr + CY_TD_SIZE >=
540 c67x00->td_base_addr + SIE_TD_SIZE))
541 return -EMSGSIZE;
542
543 if (unlikely(c67x00->next_buf_addr + len >=
544 c67x00->buf_base_addr + SIE_TD_BUF_SIZE))
545 return -EMSGSIZE;
546
547 if (periodic) {
548 if (unlikely(bit_time + c67x00->periodic_bw_allocated >=
549 MAX_PERIODIC_BW(c67x00->max_frame_bw)))
550 return -EMSGSIZE;
551 c67x00->periodic_bw_allocated += bit_time;
552 }
553
554 c67x00->bandwidth_allocated += bit_time;
555 return 0;
556}
557
558/* -------------------------------------------------------------------------- */
559
560/*
561 * td_addr and buf_addr must be word aligned
562 */
563static int c67x00_create_td(struct c67x00_hcd *c67x00, struct urb *urb,
564 void *data, int len, int pid, int toggle,
565 unsigned long privdata)
566{
567 struct c67x00_td *td;
568 struct c67x00_urb_priv *urbp = urb->hcpriv;
569 const __u8 active_flag = 1, retry_cnt = 3;
570 __u8 cmd = 0;
571 int tt = 0;
572
573 if (c67x00_claim_frame_bw(c67x00, urb, len, usb_pipeisoc(urb->pipe)
574 || usb_pipeint(urb->pipe)))
575 return -EMSGSIZE; /* Not really an error, but expected */
576
577 td = kzalloc(size: sizeof(*td), GFP_ATOMIC);
578 if (!td)
579 return -ENOMEM;
580
581 td->pipe = urb->pipe;
582 td->ep_data = urbp->ep_data;
583
584 if ((td_udev(td)->speed == USB_SPEED_LOW) &&
585 !(c67x00->low_speed_ports & (1 << urbp->port)))
586 cmd |= PREAMBLE_EN;
587
588 switch (usb_pipetype(td->pipe)) {
589 case PIPE_ISOCHRONOUS:
590 tt = TT_ISOCHRONOUS;
591 cmd |= ISO_EN;
592 break;
593 case PIPE_CONTROL:
594 tt = TT_CONTROL;
595 break;
596 case PIPE_BULK:
597 tt = TT_BULK;
598 break;
599 case PIPE_INTERRUPT:
600 tt = TT_INTERRUPT;
601 break;
602 }
603
604 if (toggle)
605 cmd |= SEQ_SEL;
606
607 cmd |= ARM_EN;
608
609 /* SW part */
610 td->td_addr = c67x00->next_td_addr;
611 c67x00->next_td_addr = c67x00->next_td_addr + CY_TD_SIZE;
612
613 /* HW part */
614 td->ly_base_addr = __cpu_to_le16(c67x00->next_buf_addr);
615 td->port_length = __cpu_to_le16((c67x00->sie->sie_num << 15) |
616 (urbp->port << 14) | (len & 0x3FF));
617 td->pid_ep = ((pid & 0xF) << TD_PIDEP_OFFSET) |
618 (usb_pipeendpoint(td->pipe) & 0xF);
619 td->dev_addr = usb_pipedevice(td->pipe) & 0x7F;
620 td->ctrl_reg = cmd;
621 td->status = 0;
622 td->retry_cnt = (tt << TT_OFFSET) | (active_flag << 4) | retry_cnt;
623 td->residue = 0;
624 td->next_td_addr = __cpu_to_le16(c67x00->next_td_addr);
625
626 /* SW part */
627 td->data = data;
628 td->urb = urb;
629 td->privdata = privdata;
630
631 c67x00->next_buf_addr += (len + 1) & ~0x01; /* properly align */
632
633 list_add_tail(new: &td->td_list, head: &c67x00->td_list);
634 return 0;
635}
636
637static inline void c67x00_release_td(struct c67x00_td *td)
638{
639 list_del_init(entry: &td->td_list);
640 kfree(objp: td);
641}
642
643/* -------------------------------------------------------------------------- */
644
645static int c67x00_add_data_urb(struct c67x00_hcd *c67x00, struct urb *urb)
646{
647 int remaining;
648 int toggle;
649 int pid;
650 int ret = 0;
651 int maxps;
652 int need_empty;
653
654 toggle = usb_gettoggle(urb->dev, usb_pipeendpoint(urb->pipe),
655 usb_pipeout(urb->pipe));
656 remaining = urb->transfer_buffer_length - urb->actual_length;
657
658 maxps = usb_maxpacket(udev: urb->dev, pipe: urb->pipe);
659
660 need_empty = (urb->transfer_flags & URB_ZERO_PACKET) &&
661 usb_pipeout(urb->pipe) && !(remaining % maxps);
662
663 while (remaining || need_empty) {
664 int len;
665 char *td_buf;
666
667 len = (remaining > maxps) ? maxps : remaining;
668 if (!len)
669 need_empty = 0;
670
671 pid = usb_pipeout(urb->pipe) ? USB_PID_OUT : USB_PID_IN;
672 td_buf = urb->transfer_buffer + urb->transfer_buffer_length -
673 remaining;
674 ret = c67x00_create_td(c67x00, urb, data: td_buf, len, pid, toggle,
675 DATA_STAGE);
676 if (ret)
677 return ret; /* td wasn't created */
678
679 toggle ^= 1;
680 remaining -= len;
681 if (usb_pipecontrol(urb->pipe))
682 break;
683 }
684
685 return 0;
686}
687
688/*
689 * return 0 in case more bandwidth is available, else errorcode
690 */
691static int c67x00_add_ctrl_urb(struct c67x00_hcd *c67x00, struct urb *urb)
692{
693 int ret;
694 int pid;
695
696 switch (urb->interval) {
697 default:
698 case SETUP_STAGE:
699 ret = c67x00_create_td(c67x00, urb, data: urb->setup_packet,
700 len: 8, USB_PID_SETUP, toggle: 0, SETUP_STAGE);
701 if (ret)
702 return ret;
703 urb->interval = SETUP_STAGE;
704 usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe),
705 usb_pipeout(urb->pipe), 1);
706 break;
707 case DATA_STAGE:
708 if (urb->transfer_buffer_length) {
709 ret = c67x00_add_data_urb(c67x00, urb);
710 if (ret)
711 return ret;
712 break;
713 }
714 fallthrough;
715 case STATUS_STAGE:
716 pid = !usb_pipeout(urb->pipe) ? USB_PID_OUT : USB_PID_IN;
717 ret = c67x00_create_td(c67x00, urb, NULL, len: 0, pid, toggle: 1,
718 STATUS_STAGE);
719 if (ret)
720 return ret;
721 break;
722 }
723
724 return 0;
725}
726
727/*
728 * return 0 in case more bandwidth is available, else errorcode
729 */
730static int c67x00_add_int_urb(struct c67x00_hcd *c67x00, struct urb *urb)
731{
732 struct c67x00_urb_priv *urbp = urb->hcpriv;
733
734 if (frame_after_eq(a: c67x00->current_frame, b: urbp->ep_data->next_frame)) {
735 urbp->ep_data->next_frame =
736 frame_add(a: urbp->ep_data->next_frame, b: urb->interval);
737 return c67x00_add_data_urb(c67x00, urb);
738 }
739 return 0;
740}
741
742static int c67x00_add_iso_urb(struct c67x00_hcd *c67x00, struct urb *urb)
743{
744 struct c67x00_urb_priv *urbp = urb->hcpriv;
745
746 if (frame_after_eq(a: c67x00->current_frame, b: urbp->ep_data->next_frame)) {
747 char *td_buf;
748 int len, pid, ret;
749
750 BUG_ON(urbp->cnt >= urb->number_of_packets);
751
752 td_buf = urb->transfer_buffer +
753 urb->iso_frame_desc[urbp->cnt].offset;
754 len = urb->iso_frame_desc[urbp->cnt].length;
755 pid = usb_pipeout(urb->pipe) ? USB_PID_OUT : USB_PID_IN;
756
757 ret = c67x00_create_td(c67x00, urb, data: td_buf, len, pid, toggle: 0,
758 privdata: urbp->cnt);
759 if (ret) {
760 dev_dbg(c67x00_hcd_dev(c67x00), "create failed: %d\n",
761 ret);
762 urb->iso_frame_desc[urbp->cnt].actual_length = 0;
763 urb->iso_frame_desc[urbp->cnt].status = ret;
764 if (urbp->cnt + 1 == urb->number_of_packets)
765 c67x00_giveback_urb(c67x00, urb, status: 0);
766 }
767
768 urbp->ep_data->next_frame =
769 frame_add(a: urbp->ep_data->next_frame, b: urb->interval);
770 urbp->cnt++;
771 }
772 return 0;
773}
774
775/* -------------------------------------------------------------------------- */
776
777static void c67x00_fill_from_list(struct c67x00_hcd *c67x00, int type,
778 int (*add)(struct c67x00_hcd *, struct urb *))
779{
780 struct c67x00_ep_data *ep_data;
781 struct urb *urb;
782
783 /* traverse every endpoint on the list */
784 list_for_each_entry(ep_data, &c67x00->list[type], node) {
785 if (!list_empty(head: &ep_data->queue)) {
786 /* and add the first urb */
787 /* isochronous transfer rely on this */
788 urb = list_entry(ep_data->queue.next,
789 struct c67x00_urb_priv,
790 hep_node)->urb;
791 add(c67x00, urb);
792 }
793 }
794}
795
796static void c67x00_fill_frame(struct c67x00_hcd *c67x00)
797{
798 struct c67x00_td *td, *ttd;
799
800 /* Check if we can proceed */
801 if (!list_empty(head: &c67x00->td_list)) {
802 dev_warn(c67x00_hcd_dev(c67x00),
803 "TD list not empty! This should not happen!\n");
804 list_for_each_entry_safe(td, ttd, &c67x00->td_list, td_list) {
805 dbg_td(c67x00, td, msg: "Unprocessed td");
806 c67x00_release_td(td);
807 }
808 }
809
810 /* Reinitialize variables */
811 c67x00->bandwidth_allocated = 0;
812 c67x00->periodic_bw_allocated = 0;
813
814 c67x00->next_td_addr = c67x00->td_base_addr;
815 c67x00->next_buf_addr = c67x00->buf_base_addr;
816
817 /* Fill the list */
818 c67x00_fill_from_list(c67x00, PIPE_ISOCHRONOUS, add: c67x00_add_iso_urb);
819 c67x00_fill_from_list(c67x00, PIPE_INTERRUPT, add: c67x00_add_int_urb);
820 c67x00_fill_from_list(c67x00, PIPE_CONTROL, add: c67x00_add_ctrl_urb);
821 c67x00_fill_from_list(c67x00, PIPE_BULK, add: c67x00_add_data_urb);
822}
823
824/* -------------------------------------------------------------------------- */
825
826/*
827 * Get TD from C67X00
828 */
829static inline void
830c67x00_parse_td(struct c67x00_hcd *c67x00, struct c67x00_td *td)
831{
832 c67x00_ll_read_mem_le16(dev: c67x00->sie->dev,
833 addr: td->td_addr, data: td, CY_TD_SIZE);
834
835 if (usb_pipein(td->pipe) && td_actual_bytes(td))
836 c67x00_ll_read_mem_le16(dev: c67x00->sie->dev, td_ly_base_addr(td),
837 data: td->data, td_actual_bytes(td));
838}
839
840static int c67x00_td_to_error(struct c67x00_hcd *c67x00, struct c67x00_td *td)
841{
842 if (td->status & TD_STATUSMASK_ERR) {
843 dbg_td(c67x00, td, msg: "ERROR_FLAG");
844 return -EILSEQ;
845 }
846 if (td->status & TD_STATUSMASK_STALL) {
847 /* dbg_td(c67x00, td, "STALL"); */
848 return -EPIPE;
849 }
850 if (td->status & TD_STATUSMASK_TMOUT) {
851 dbg_td(c67x00, td, msg: "TIMEOUT");
852 return -ETIMEDOUT;
853 }
854
855 return 0;
856}
857
858static inline int c67x00_end_of_data(struct c67x00_td *td)
859{
860 int maxps, need_empty, remaining;
861 struct urb *urb = td->urb;
862 int act_bytes;
863
864 act_bytes = td_actual_bytes(td);
865
866 if (unlikely(!act_bytes))
867 return 1; /* This was an empty packet */
868
869 maxps = usb_maxpacket(td_udev(td), pipe: td->pipe);
870
871 if (unlikely(act_bytes < maxps))
872 return 1; /* Smaller then full packet */
873
874 remaining = urb->transfer_buffer_length - urb->actual_length;
875 need_empty = (urb->transfer_flags & URB_ZERO_PACKET) &&
876 usb_pipeout(urb->pipe) && !(remaining % maxps);
877
878 if (unlikely(!remaining && !need_empty))
879 return 1;
880
881 return 0;
882}
883
884/* -------------------------------------------------------------------------- */
885
886/* Remove all td's from the list which come
887 * after last_td and are meant for the same pipe.
888 * This is used when a short packet has occurred */
889static inline void c67x00_clear_pipe(struct c67x00_hcd *c67x00,
890 struct c67x00_td *last_td)
891{
892 struct c67x00_td *td, *tmp;
893 td = last_td;
894 tmp = last_td;
895 while (td->td_list.next != &c67x00->td_list) {
896 td = list_entry(td->td_list.next, struct c67x00_td, td_list);
897 if (td->pipe == last_td->pipe) {
898 c67x00_release_td(td);
899 td = tmp;
900 }
901 tmp = td;
902 }
903}
904
905/* -------------------------------------------------------------------------- */
906
907static void c67x00_handle_successful_td(struct c67x00_hcd *c67x00,
908 struct c67x00_td *td)
909{
910 struct urb *urb = td->urb;
911
912 if (!urb)
913 return;
914
915 urb->actual_length += td_actual_bytes(td);
916
917 switch (usb_pipetype(td->pipe)) {
918 /* isochronous tds are handled separately */
919 case PIPE_CONTROL:
920 switch (td->privdata) {
921 case SETUP_STAGE:
922 urb->interval =
923 urb->transfer_buffer_length ?
924 DATA_STAGE : STATUS_STAGE;
925 /* Don't count setup_packet with normal data: */
926 urb->actual_length = 0;
927 break;
928
929 case DATA_STAGE:
930 if (c67x00_end_of_data(td)) {
931 urb->interval = STATUS_STAGE;
932 c67x00_clear_pipe(c67x00, last_td: td);
933 }
934 break;
935
936 case STATUS_STAGE:
937 urb->interval = 0;
938 c67x00_giveback_urb(c67x00, urb, status: 0);
939 break;
940 }
941 break;
942
943 case PIPE_INTERRUPT:
944 case PIPE_BULK:
945 if (unlikely(c67x00_end_of_data(td))) {
946 c67x00_clear_pipe(c67x00, last_td: td);
947 c67x00_giveback_urb(c67x00, urb, status: 0);
948 }
949 break;
950 }
951}
952
953static void c67x00_handle_isoc(struct c67x00_hcd *c67x00, struct c67x00_td *td)
954{
955 struct urb *urb = td->urb;
956 int cnt;
957
958 if (!urb)
959 return;
960
961 cnt = td->privdata;
962
963 if (td->status & TD_ERROR_MASK)
964 urb->error_count++;
965
966 urb->iso_frame_desc[cnt].actual_length = td_actual_bytes(td);
967 urb->iso_frame_desc[cnt].status = c67x00_td_to_error(c67x00, td);
968 if (cnt + 1 == urb->number_of_packets) /* Last packet */
969 c67x00_giveback_urb(c67x00, urb, status: 0);
970}
971
972/* -------------------------------------------------------------------------- */
973
974/*
975 * c67x00_check_td_list - handle tds which have been processed by the c67x00
976 * pre: current_td == 0
977 */
978static inline void c67x00_check_td_list(struct c67x00_hcd *c67x00)
979{
980 struct c67x00_td *td, *tmp;
981 struct urb *urb;
982 int ack_ok;
983 int clear_endpoint;
984
985 list_for_each_entry_safe(td, tmp, &c67x00->td_list, td_list) {
986 /* get the TD */
987 c67x00_parse_td(c67x00, td);
988 urb = td->urb; /* urb can be NULL! */
989 ack_ok = 0;
990 clear_endpoint = 1;
991
992 /* Handle isochronous transfers separately */
993 if (usb_pipeisoc(td->pipe)) {
994 clear_endpoint = 0;
995 c67x00_handle_isoc(c67x00, td);
996 goto cont;
997 }
998
999 /* When an error occurs, all td's for that pipe go into an
1000 * inactive state. This state matches successful transfers so
1001 * we must make sure not to service them. */
1002 if (td->status & TD_ERROR_MASK) {
1003 c67x00_giveback_urb(c67x00, urb,
1004 status: c67x00_td_to_error(c67x00, td));
1005 goto cont;
1006 }
1007
1008 if ((td->status & TD_STATUSMASK_NAK) || !td_sequence_ok(td) ||
1009 !td_acked(td))
1010 goto cont;
1011
1012 /* Sequence ok and acked, don't need to fix toggle */
1013 ack_ok = 1;
1014
1015 if (unlikely(td->status & TD_STATUSMASK_OVF)) {
1016 if (td_residue(td) & TD_RESIDUE_OVERFLOW) {
1017 /* Overflow */
1018 c67x00_giveback_urb(c67x00, urb, status: -EOVERFLOW);
1019 goto cont;
1020 }
1021 }
1022
1023 clear_endpoint = 0;
1024 c67x00_handle_successful_td(c67x00, td);
1025
1026cont:
1027 if (clear_endpoint)
1028 c67x00_clear_pipe(c67x00, last_td: td);
1029 if (ack_ok)
1030 usb_settoggle(td_udev(td), usb_pipeendpoint(td->pipe),
1031 usb_pipeout(td->pipe),
1032 !(td->ctrl_reg & SEQ_SEL));
1033 /* next in list could have been removed, due to clear_pipe! */
1034 tmp = list_entry(td->td_list.next, typeof(*td), td_list);
1035 c67x00_release_td(td);
1036 }
1037}
1038
1039/* -------------------------------------------------------------------------- */
1040
1041static inline int c67x00_all_tds_processed(struct c67x00_hcd *c67x00)
1042{
1043 /* If all tds are processed, we can check the previous frame (if
1044 * there was any) and start our next frame.
1045 */
1046 return !c67x00_ll_husb_get_current_td(sie: c67x00->sie);
1047}
1048
1049/*
1050 * Send td to C67X00
1051 */
1052static void c67x00_send_td(struct c67x00_hcd *c67x00, struct c67x00_td *td)
1053{
1054 int len = td_length(td);
1055
1056 if (len && ((td->pid_ep & TD_PIDEPMASK_PID) != TD_PID_IN))
1057 c67x00_ll_write_mem_le16(dev: c67x00->sie->dev, td_ly_base_addr(td),
1058 data: td->data, len);
1059
1060 c67x00_ll_write_mem_le16(dev: c67x00->sie->dev,
1061 addr: td->td_addr, data: td, CY_TD_SIZE);
1062}
1063
1064static void c67x00_send_frame(struct c67x00_hcd *c67x00)
1065{
1066 struct c67x00_td *td;
1067
1068 if (list_empty(head: &c67x00->td_list))
1069 dev_warn(c67x00_hcd_dev(c67x00),
1070 "%s: td list should not be empty here!\n",
1071 __func__);
1072
1073 list_for_each_entry(td, &c67x00->td_list, td_list) {
1074 if (td->td_list.next == &c67x00->td_list)
1075 td->next_td_addr = 0; /* Last td in list */
1076
1077 c67x00_send_td(c67x00, td);
1078 }
1079
1080 c67x00_ll_husb_set_current_td(sie: c67x00->sie, addr: c67x00->td_base_addr);
1081}
1082
1083/* -------------------------------------------------------------------------- */
1084
1085/*
1086 * c67x00_do_work - Schedulers state machine
1087 */
1088static void c67x00_do_work(struct c67x00_hcd *c67x00)
1089{
1090 spin_lock(lock: &c67x00->lock);
1091 /* Make sure all tds are processed */
1092 if (!c67x00_all_tds_processed(c67x00))
1093 goto out;
1094
1095 c67x00_check_td_list(c67x00);
1096
1097 /* no td's are being processed (current == 0)
1098 * and all have been "checked" */
1099 complete(&c67x00->endpoint_disable);
1100
1101 if (!list_empty(head: &c67x00->td_list))
1102 goto out;
1103
1104 c67x00->current_frame = c67x00_get_current_frame_number(c67x00);
1105 if (c67x00->current_frame == c67x00->last_frame)
1106 goto out; /* Don't send tds in same frame */
1107 c67x00->last_frame = c67x00->current_frame;
1108
1109 /* If no urbs are scheduled, our work is done */
1110 if (!c67x00->urb_count) {
1111 c67x00_ll_hpi_disable_sofeop(sie: c67x00->sie);
1112 goto out;
1113 }
1114
1115 c67x00_fill_frame(c67x00);
1116 if (!list_empty(head: &c67x00->td_list))
1117 /* TD's have been added to the frame */
1118 c67x00_send_frame(c67x00);
1119
1120 out:
1121 spin_unlock(lock: &c67x00->lock);
1122}
1123
1124/* -------------------------------------------------------------------------- */
1125
1126static void c67x00_sched_work(struct work_struct *work)
1127{
1128 struct c67x00_hcd *c67x00;
1129
1130 c67x00 = container_of(work, struct c67x00_hcd, work);
1131 c67x00_do_work(c67x00);
1132}
1133
1134void c67x00_sched_kick(struct c67x00_hcd *c67x00)
1135{
1136 queue_work(wq: system_highpri_wq, work: &c67x00->work);
1137}
1138
1139int c67x00_sched_start_scheduler(struct c67x00_hcd *c67x00)
1140{
1141 INIT_WORK(&c67x00->work, c67x00_sched_work);
1142 return 0;
1143}
1144
1145void c67x00_sched_stop_scheduler(struct c67x00_hcd *c67x00)
1146{
1147 cancel_work_sync(work: &c67x00->work);
1148}
1149

source code of linux/drivers/usb/c67x00/c67x00-sched.c