1 /*
2  * c67x00-sched.c: Cypress C67X00 USB Host Controller Driver - TD scheduling
3  *
4  * Copyright (C) 2006-2008 Barco N.V.
5  *    Derived from the Cypress cy7c67200/300 ezusb linux driver and
6  *    based on multiple host controller drivers inside the linux kernel.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
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  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
21  * MA  02110-1301  USA.
22  */
23 
24 #include <linux/kthread.h>
25 
26 #include "c67x00.h"
27 #include "c67x00-hcd.h"
28 
29 /*
30  * These are the stages for a control urb, they are kept
31  * in both urb->interval and td->privdata.
32  */
33 #define SETUP_STAGE		0
34 #define DATA_STAGE		1
35 #define STATUS_STAGE		2
36 
37 /* -------------------------------------------------------------------------- */
38 
39 /**
40  * struct c67x00_ep_data: Host endpoint data structure
41  */
42 struct c67x00_ep_data {
43 	struct list_head queue;
44 	struct list_head node;
45 	struct usb_host_endpoint *hep;
46 	struct usb_device *dev;
47 	u16 next_frame;		/* For int/isoc transactions */
48 };
49 
50 /**
51  * struct c67x00_td
52  *
53  * Hardware parts are little endiannes, SW in CPU endianess.
54  */
55 struct c67x00_td {
56 	/* HW specific part */
57 	__le16 ly_base_addr;	/* Bytes 0-1 */
58 	__le16 port_length;	/* Bytes 2-3 */
59 	u8 pid_ep;		/* Byte 4 */
60 	u8 dev_addr;		/* Byte 5 */
61 	u8 ctrl_reg;		/* Byte 6 */
62 	u8 status;		/* Byte 7 */
63 	u8 retry_cnt;		/* Byte 8 */
64 #define TT_OFFSET		2
65 #define TT_CONTROL		0
66 #define TT_ISOCHRONOUS		1
67 #define TT_BULK			2
68 #define TT_INTERRUPT		3
69 	u8 residue;		/* Byte 9 */
70 	__le16 next_td_addr;	/* Bytes 10-11 */
71 	/* SW part */
72 	struct list_head td_list;
73 	u16 td_addr;
74 	void *data;
75 	struct urb *urb;
76 	unsigned long privdata;
77 
78 	/* These are needed for handling the toggle bits:
79 	 * an urb can be dequeued while a td is in progress
80 	 * after checking the td, the toggle bit might need to
81 	 * be fixed */
82 	struct c67x00_ep_data *ep_data;
83 	unsigned int pipe;
84 };
85 
86 struct c67x00_urb_priv {
87 	struct list_head hep_node;
88 	struct urb *urb;
89 	int port;
90 	int cnt;		/* packet number for isoc */
91 	int status;
92 	struct c67x00_ep_data *ep_data;
93 };
94 
95 #define td_udev(td)	((td)->ep_data->dev)
96 
97 #define CY_TD_SIZE		12
98 
99 #define TD_PIDEP_OFFSET		0x04
100 #define TD_PIDEPMASK_PID	0xF0
101 #define TD_PIDEPMASK_EP		0x0F
102 #define TD_PORTLENMASK_DL	0x02FF
103 #define TD_PORTLENMASK_PN	0xC000
104 
105 #define TD_STATUS_OFFSET	0x07
106 #define TD_STATUSMASK_ACK	0x01
107 #define TD_STATUSMASK_ERR	0x02
108 #define TD_STATUSMASK_TMOUT	0x04
109 #define TD_STATUSMASK_SEQ	0x08
110 #define TD_STATUSMASK_SETUP	0x10
111 #define TD_STATUSMASK_OVF	0x20
112 #define TD_STATUSMASK_NAK	0x40
113 #define TD_STATUSMASK_STALL	0x80
114 
115 #define TD_ERROR_MASK		(TD_STATUSMASK_ERR | TD_STATUSMASK_TMOUT | \
116 				 TD_STATUSMASK_STALL)
117 
118 #define TD_RETRYCNT_OFFSET	0x08
119 #define TD_RETRYCNTMASK_ACT_FLG	0x10
120 #define TD_RETRYCNTMASK_TX_TYPE	0x0C
121 #define TD_RETRYCNTMASK_RTY_CNT	0x03
122 
123 #define TD_RESIDUE_OVERFLOW	0x80
124 
125 #define TD_PID_IN		0x90
126 
127 /* Residue: signed 8bits, neg -> OVERFLOW, pos -> UNDERFLOW */
128 #define td_residue(td)		((__s8)(td->residue))
129 #define td_ly_base_addr(td)	(__le16_to_cpu((td)->ly_base_addr))
130 #define td_port_length(td)	(__le16_to_cpu((td)->port_length))
131 #define td_next_td_addr(td)	(__le16_to_cpu((td)->next_td_addr))
132 
133 #define td_active(td)		((td)->retry_cnt & TD_RETRYCNTMASK_ACT_FLG)
134 #define td_length(td)		(td_port_length(td) & TD_PORTLENMASK_DL)
135 
136 #define td_sequence_ok(td)	(!td->status || \
137 				 (!(td->status & TD_STATUSMASK_SEQ) ==	\
138 				  !(td->ctrl_reg & SEQ_SEL)))
139 
140 #define td_acked(td)		(!td->status || \
141 				 (td->status & TD_STATUSMASK_ACK))
142 #define td_actual_bytes(td)	(td_length(td) - td_residue(td))
143 
144 /* -------------------------------------------------------------------------- */
145 
146 #ifdef DEBUG
147 
148 /**
149  * dbg_td - Dump the contents of the TD
150  */
151 static void dbg_td(struct c67x00_hcd *c67x00, struct c67x00_td *td, char *msg)
152 {
153 	struct device *dev = c67x00_hcd_dev(c67x00);
154 
155 	dev_dbg(dev, "### %s at 0x%04x\n", msg, td->td_addr);
156 	dev_dbg(dev, "urb:      0x%p\n", td->urb);
157 	dev_dbg(dev, "endpoint:   %4d\n", usb_pipeendpoint(td->pipe));
158 	dev_dbg(dev, "pipeout:    %4d\n", usb_pipeout(td->pipe));
159 	dev_dbg(dev, "ly_base_addr: 0x%04x\n", td_ly_base_addr(td));
160 	dev_dbg(dev, "port_length:  0x%04x\n", td_port_length(td));
161 	dev_dbg(dev, "pid_ep:         0x%02x\n", td->pid_ep);
162 	dev_dbg(dev, "dev_addr:       0x%02x\n", td->dev_addr);
163 	dev_dbg(dev, "ctrl_reg:       0x%02x\n", td->ctrl_reg);
164 	dev_dbg(dev, "status:         0x%02x\n", td->status);
165 	dev_dbg(dev, "retry_cnt:      0x%02x\n", td->retry_cnt);
166 	dev_dbg(dev, "residue:        0x%02x\n", td->residue);
167 	dev_dbg(dev, "next_td_addr: 0x%04x\n", td_next_td_addr(td));
168 	dev_dbg(dev, "data:");
169 	print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 16, 1,
170 		       td->data, td_length(td), 1);
171 }
172 #else				/* DEBUG */
173 
174 static inline void
175 dbg_td(struct c67x00_hcd *c67x00, struct c67x00_td *td, char *msg) { }
176 
177 #endif				/* DEBUG */
178 
179 /* -------------------------------------------------------------------------- */
180 /* Helper functions */
181 
182 static inline u16 c67x00_get_current_frame_number(struct c67x00_hcd *c67x00)
183 {
184 	return c67x00_ll_husb_get_frame(c67x00->sie) & HOST_FRAME_MASK;
185 }
186 
187 /**
188  * frame_add
189  * Software wraparound for framenumbers.
190  */
191 static inline u16 frame_add(u16 a, u16 b)
192 {
193 	return (a + b) & HOST_FRAME_MASK;
194 }
195 
196 /**
197  * frame_after - is frame a after frame b
198  */
199 static inline int frame_after(u16 a, u16 b)
200 {
201 	return ((HOST_FRAME_MASK + a - b) & HOST_FRAME_MASK) <
202 	    (HOST_FRAME_MASK / 2);
203 }
204 
205 /**
206  * frame_after_eq - is frame a after or equal to frame b
207  */
208 static inline int frame_after_eq(u16 a, u16 b)
209 {
210 	return ((HOST_FRAME_MASK + 1 + a - b) & HOST_FRAME_MASK) <
211 	    (HOST_FRAME_MASK / 2);
212 }
213 
214 /* -------------------------------------------------------------------------- */
215 
216 /**
217  * c67x00_release_urb - remove link from all tds to this urb
218  * Disconnects the urb from it's tds, so that it can be given back.
219  * pre: urb->hcpriv != NULL
220  */
221 static void c67x00_release_urb(struct c67x00_hcd *c67x00, struct urb *urb)
222 {
223 	struct c67x00_td *td;
224 	struct c67x00_urb_priv *urbp;
225 
226 	BUG_ON(!urb);
227 
228 	c67x00->urb_count--;
229 
230 	if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) {
231 		c67x00->urb_iso_count--;
232 		if (c67x00->urb_iso_count == 0)
233 			c67x00->max_frame_bw = MAX_FRAME_BW_STD;
234 	}
235 
236 	/* TODO this might be not so efficient when we've got many urbs!
237 	 * Alternatives:
238 	 *   * only clear when needed
239 	 *   * keep a list of tds with each urbp
240 	 */
241 	list_for_each_entry(td, &c67x00->td_list, td_list)
242 		if (urb == td->urb)
243 			td->urb = NULL;
244 
245 	urbp = urb->hcpriv;
246 	urb->hcpriv = NULL;
247 	list_del(&urbp->hep_node);
248 	kfree(urbp);
249 }
250 
251 /* -------------------------------------------------------------------------- */
252 
253 static struct c67x00_ep_data *
254 c67x00_ep_data_alloc(struct c67x00_hcd *c67x00, struct urb *urb)
255 {
256 	struct usb_host_endpoint *hep = urb->ep;
257 	struct c67x00_ep_data *ep_data;
258 	int type;
259 
260 	c67x00->current_frame = c67x00_get_current_frame_number(c67x00);
261 
262 	/* Check if endpoint already has a c67x00_ep_data struct allocated */
263 	if (hep->hcpriv) {
264 		ep_data = hep->hcpriv;
265 		if (frame_after(c67x00->current_frame, ep_data->next_frame))
266 			ep_data->next_frame =
267 			    frame_add(c67x00->current_frame, 1);
268 		return hep->hcpriv;
269 	}
270 
271 	/* Allocate and initialize a new c67x00 endpoint data structure */
272 	ep_data = kzalloc(sizeof(*ep_data), GFP_ATOMIC);
273 	if (!ep_data)
274 		return NULL;
275 
276 	INIT_LIST_HEAD(&ep_data->queue);
277 	INIT_LIST_HEAD(&ep_data->node);
278 	ep_data->hep = hep;
279 
280 	/* hold a reference to udev as long as this endpoint lives,
281 	 * this is needed to possibly fix the data toggle */
282 	ep_data->dev = usb_get_dev(urb->dev);
283 	hep->hcpriv = ep_data;
284 
285 	/* For ISOC and INT endpoints, start ASAP: */
286 	ep_data->next_frame = frame_add(c67x00->current_frame, 1);
287 
288 	/* Add the endpoint data to one of the pipe lists; must be added
289 	   in order of endpoint address */
290 	type = usb_pipetype(urb->pipe);
291 	if (list_empty(&ep_data->node)) {
292 		list_add(&ep_data->node, &c67x00->list[type]);
293 	} else {
294 		struct c67x00_ep_data *prev;
295 
296 		list_for_each_entry(prev, &c67x00->list[type], node) {
297 			if (prev->hep->desc.bEndpointAddress >
298 			    hep->desc.bEndpointAddress) {
299 				list_add(&ep_data->node, prev->node.prev);
300 				break;
301 			}
302 		}
303 	}
304 
305 	return ep_data;
306 }
307 
308 static int c67x00_ep_data_free(struct usb_host_endpoint *hep)
309 {
310 	struct c67x00_ep_data *ep_data = hep->hcpriv;
311 
312 	if (!ep_data)
313 		return 0;
314 
315 	if (!list_empty(&ep_data->queue))
316 		return -EBUSY;
317 
318 	usb_put_dev(ep_data->dev);
319 	list_del(&ep_data->queue);
320 	list_del(&ep_data->node);
321 
322 	kfree(ep_data);
323 	hep->hcpriv = NULL;
324 
325 	return 0;
326 }
327 
328 void c67x00_endpoint_disable(struct usb_hcd *hcd, struct usb_host_endpoint *ep)
329 {
330 	struct c67x00_hcd *c67x00 = hcd_to_c67x00_hcd(hcd);
331 	unsigned long flags;
332 
333 	if (!list_empty(&ep->urb_list))
334 		dev_warn(c67x00_hcd_dev(c67x00), "error: urb list not empty\n");
335 
336 	spin_lock_irqsave(&c67x00->lock, flags);
337 
338 	/* loop waiting for all transfers in the endpoint queue to complete */
339 	while (c67x00_ep_data_free(ep)) {
340 		/* Drop the lock so we can sleep waiting for the hardware */
341 		spin_unlock_irqrestore(&c67x00->lock, flags);
342 
343 		/* it could happen that we reinitialize this completion, while
344 		 * somebody was waiting for that completion.  The timeout and
345 		 * while loop handle such cases, but this might be improved */
346 		INIT_COMPLETION(c67x00->endpoint_disable);
347 		c67x00_sched_kick(c67x00);
348 		wait_for_completion_timeout(&c67x00->endpoint_disable, 1 * HZ);
349 
350 		spin_lock_irqsave(&c67x00->lock, flags);
351 	}
352 
353 	spin_unlock_irqrestore(&c67x00->lock, flags);
354 }
355 
356 /* -------------------------------------------------------------------------- */
357 
358 static inline int get_root_port(struct usb_device *dev)
359 {
360 	while (dev->parent->parent)
361 		dev = dev->parent;
362 	return dev->portnum;
363 }
364 
365 int c67x00_urb_enqueue(struct usb_hcd *hcd,
366 		       struct urb *urb, gfp_t mem_flags)
367 {
368 	int ret;
369 	unsigned long flags;
370 	struct c67x00_urb_priv *urbp;
371 	struct c67x00_hcd *c67x00 = hcd_to_c67x00_hcd(hcd);
372 	int port = get_root_port(urb->dev)-1;
373 
374 	spin_lock_irqsave(&c67x00->lock, flags);
375 
376 	/* Make sure host controller is running */
377 	if (!HC_IS_RUNNING(hcd->state)) {
378 		ret = -ENODEV;
379 		goto err_not_linked;
380 	}
381 
382 	ret = usb_hcd_link_urb_to_ep(hcd, urb);
383 	if (ret)
384 		goto err_not_linked;
385 
386 	/* Allocate and initialize urb private data */
387 	urbp = kzalloc(sizeof(*urbp), mem_flags);
388 	if (!urbp) {
389 		ret = -ENOMEM;
390 		goto err_urbp;
391 	}
392 
393 	INIT_LIST_HEAD(&urbp->hep_node);
394 	urbp->urb = urb;
395 	urbp->port = port;
396 
397 	urbp->ep_data = c67x00_ep_data_alloc(c67x00, urb);
398 
399 	if (!urbp->ep_data) {
400 		ret = -ENOMEM;
401 		goto err_epdata;
402 	}
403 
404 	/* TODO claim bandwidth with usb_claim_bandwidth?
405 	 * also release it somewhere! */
406 
407 	urb->hcpriv = urbp;
408 
409 	urb->actual_length = 0;	/* Nothing received/transmitted yet */
410 
411 	switch (usb_pipetype(urb->pipe)) {
412 	case PIPE_CONTROL:
413 		urb->interval = SETUP_STAGE;
414 		break;
415 	case PIPE_INTERRUPT:
416 		break;
417 	case PIPE_BULK:
418 		break;
419 	case PIPE_ISOCHRONOUS:
420 		if (c67x00->urb_iso_count == 0)
421 			c67x00->max_frame_bw = MAX_FRAME_BW_ISO;
422 		c67x00->urb_iso_count++;
423 		/* Assume always URB_ISO_ASAP, FIXME */
424 		if (list_empty(&urbp->ep_data->queue))
425 			urb->start_frame = urbp->ep_data->next_frame;
426 		else {
427 			/* Go right after the last one */
428 			struct urb *last_urb;
429 
430 			last_urb = list_entry(urbp->ep_data->queue.prev,
431 					      struct c67x00_urb_priv,
432 					      hep_node)->urb;
433 			urb->start_frame =
434 			    frame_add(last_urb->start_frame,
435 				      last_urb->number_of_packets *
436 				      last_urb->interval);
437 		}
438 		urbp->cnt = 0;
439 		break;
440 	}
441 
442 	/* Add the URB to the endpoint queue */
443 	list_add_tail(&urbp->hep_node, &urbp->ep_data->queue);
444 
445 	/* If this is the only URB, kick start the controller */
446 	if (!c67x00->urb_count++)
447 		c67x00_ll_hpi_enable_sofeop(c67x00->sie);
448 
449 	c67x00_sched_kick(c67x00);
450 	spin_unlock_irqrestore(&c67x00->lock, flags);
451 
452 	return 0;
453 
454 err_epdata:
455 	kfree(urbp);
456 err_urbp:
457 	usb_hcd_unlink_urb_from_ep(hcd, urb);
458 err_not_linked:
459 	spin_unlock_irqrestore(&c67x00->lock, flags);
460 
461 	return ret;
462 }
463 
464 int c67x00_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
465 {
466 	struct c67x00_hcd *c67x00 = hcd_to_c67x00_hcd(hcd);
467 	unsigned long flags;
468 	int rc;
469 
470 	spin_lock_irqsave(&c67x00->lock, flags);
471 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
472 	if (rc)
473 		goto done;
474 
475 	c67x00_release_urb(c67x00, urb);
476 	usb_hcd_unlink_urb_from_ep(hcd, urb);
477 
478 	spin_unlock(&c67x00->lock);
479 	usb_hcd_giveback_urb(hcd, urb, status);
480 	spin_lock(&c67x00->lock);
481 
482 	spin_unlock_irqrestore(&c67x00->lock, flags);
483 
484 	return 0;
485 
486  done:
487 	spin_unlock_irqrestore(&c67x00->lock, flags);
488 	return rc;
489 }
490 
491 /* -------------------------------------------------------------------------- */
492 
493 /*
494  * pre: c67x00 locked, urb unlocked
495  */
496 static void
497 c67x00_giveback_urb(struct c67x00_hcd *c67x00, struct urb *urb, int status)
498 {
499 	struct c67x00_urb_priv *urbp;
500 
501 	if (!urb)
502 		return;
503 
504 	urbp = urb->hcpriv;
505 	urbp->status = status;
506 
507 	list_del_init(&urbp->hep_node);
508 
509 	c67x00_release_urb(c67x00, urb);
510 	usb_hcd_unlink_urb_from_ep(c67x00_hcd_to_hcd(c67x00), urb);
511 	spin_unlock(&c67x00->lock);
512 	usb_hcd_giveback_urb(c67x00_hcd_to_hcd(c67x00), urb, urbp->status);
513 	spin_lock(&c67x00->lock);
514 }
515 
516 /* -------------------------------------------------------------------------- */
517 
518 static int c67x00_claim_frame_bw(struct c67x00_hcd *c67x00, struct urb *urb,
519 				 int len, int periodic)
520 {
521 	struct c67x00_urb_priv *urbp = urb->hcpriv;
522 	int bit_time;
523 
524 	/* According to the C67x00 BIOS user manual, page 3-18,19, the
525 	 * following calculations provide the full speed bit times for
526 	 * a transaction.
527 	 *
528 	 * FS(in)	= 112.5 +  9.36*BC + HOST_DELAY
529 	 * FS(in,iso)	=  90.5 +  9.36*BC + HOST_DELAY
530 	 * FS(out)	= 112.5 +  9.36*BC + HOST_DELAY
531 	 * FS(out,iso)	=  78.4 +  9.36*BC + HOST_DELAY
532 	 * LS(in)	= 802.4 + 75.78*BC + HOST_DELAY
533 	 * LS(out)	= 802.6 + 74.67*BC + HOST_DELAY
534 	 *
535 	 * HOST_DELAY == 106 for the c67200 and c67300.
536 	 */
537 
538 	/* make calculations in 1/100 bit times to maintain resolution */
539 	if (urbp->ep_data->dev->speed == USB_SPEED_LOW) {
540 		/* Low speed pipe */
541 		if (usb_pipein(urb->pipe))
542 			bit_time = 80240 + 7578*len;
543 		else
544 			bit_time = 80260 + 7467*len;
545 	} else {
546 		/* FS pipes */
547 		if (usb_pipeisoc(urb->pipe))
548 			bit_time = usb_pipein(urb->pipe) ? 9050 : 7840;
549 		else
550 			bit_time = 11250;
551 		bit_time += 936*len;
552 	}
553 
554 	/* Scale back down to integer bit times.  Use a host delay of 106.
555 	 * (this is the only place it is used) */
556 	bit_time = ((bit_time+50) / 100) + 106;
557 
558 	if (unlikely(bit_time + c67x00->bandwidth_allocated >=
559 		     c67x00->max_frame_bw))
560 		return -EMSGSIZE;
561 
562 	if (unlikely(c67x00->next_td_addr + CY_TD_SIZE >=
563 		     c67x00->td_base_addr + SIE_TD_SIZE))
564 		return -EMSGSIZE;
565 
566 	if (unlikely(c67x00->next_buf_addr + len >=
567 		     c67x00->buf_base_addr + SIE_TD_BUF_SIZE))
568 		return -EMSGSIZE;
569 
570 	if (periodic) {
571 		if (unlikely(bit_time + c67x00->periodic_bw_allocated >=
572 			     MAX_PERIODIC_BW(c67x00->max_frame_bw)))
573 			return -EMSGSIZE;
574 		c67x00->periodic_bw_allocated += bit_time;
575 	}
576 
577 	c67x00->bandwidth_allocated += bit_time;
578 	return 0;
579 }
580 
581 /* -------------------------------------------------------------------------- */
582 
583 /**
584  * td_addr and buf_addr must be word aligned
585  */
586 static int c67x00_create_td(struct c67x00_hcd *c67x00, struct urb *urb,
587 			    void *data, int len, int pid, int toggle,
588 			    unsigned long privdata)
589 {
590 	struct c67x00_td *td;
591 	struct c67x00_urb_priv *urbp = urb->hcpriv;
592 	const __u8 active_flag = 1, retry_cnt = 1;
593 	__u8 cmd = 0;
594 	int tt = 0;
595 
596 	if (c67x00_claim_frame_bw(c67x00, urb, len, usb_pipeisoc(urb->pipe)
597 				  || usb_pipeint(urb->pipe)))
598 		return -EMSGSIZE;	/* Not really an error, but expected */
599 
600 	td = kzalloc(sizeof(*td), GFP_ATOMIC);
601 	if (!td)
602 		return -ENOMEM;
603 
604 	td->pipe = urb->pipe;
605 	td->ep_data = urbp->ep_data;
606 
607 	if ((td_udev(td)->speed == USB_SPEED_LOW) &&
608 	    !(c67x00->low_speed_ports & (1 << urbp->port)))
609 		cmd |= PREAMBLE_EN;
610 
611 	switch (usb_pipetype(td->pipe)) {
612 	case PIPE_ISOCHRONOUS:
613 		tt = TT_ISOCHRONOUS;
614 		cmd |= ISO_EN;
615 		break;
616 	case PIPE_CONTROL:
617 		tt = TT_CONTROL;
618 		break;
619 	case PIPE_BULK:
620 		tt = TT_BULK;
621 		break;
622 	case PIPE_INTERRUPT:
623 		tt = TT_INTERRUPT;
624 		break;
625 	}
626 
627 	if (toggle)
628 		cmd |= SEQ_SEL;
629 
630 	cmd |= ARM_EN;
631 
632 	/* SW part */
633 	td->td_addr = c67x00->next_td_addr;
634 	c67x00->next_td_addr = c67x00->next_td_addr + CY_TD_SIZE;
635 
636 	/* HW part */
637 	td->ly_base_addr = __cpu_to_le16(c67x00->next_buf_addr);
638 	td->port_length = __cpu_to_le16((c67x00->sie->sie_num << 15) |
639 					(urbp->port << 14) | (len & 0x3FF));
640 	td->pid_ep = ((pid & 0xF) << TD_PIDEP_OFFSET) |
641 	    (usb_pipeendpoint(td->pipe) & 0xF);
642 	td->dev_addr = usb_pipedevice(td->pipe) & 0x7F;
643 	td->ctrl_reg = cmd;
644 	td->status = 0;
645 	td->retry_cnt = (tt << TT_OFFSET) | (active_flag << 4) | retry_cnt;
646 	td->residue = 0;
647 	td->next_td_addr = __cpu_to_le16(c67x00->next_td_addr);
648 
649 	/* SW part */
650 	td->data = data;
651 	td->urb = urb;
652 	td->privdata = privdata;
653 
654 	c67x00->next_buf_addr += (len + 1) & ~0x01;	/* properly align */
655 
656 	list_add_tail(&td->td_list, &c67x00->td_list);
657 	return 0;
658 }
659 
660 static inline void c67x00_release_td(struct c67x00_td *td)
661 {
662 	list_del_init(&td->td_list);
663 	kfree(td);
664 }
665 
666 /* -------------------------------------------------------------------------- */
667 
668 static int c67x00_add_data_urb(struct c67x00_hcd *c67x00, struct urb *urb)
669 {
670 	int remaining;
671 	int toggle;
672 	int pid;
673 	int ret = 0;
674 	int maxps;
675 	int need_empty;
676 
677 	toggle = usb_gettoggle(urb->dev, usb_pipeendpoint(urb->pipe),
678 			       usb_pipeout(urb->pipe));
679 	remaining = urb->transfer_buffer_length - urb->actual_length;
680 
681 	maxps = usb_maxpacket(urb->dev, urb->pipe, usb_pipeout(urb->pipe));
682 
683 	need_empty = (urb->transfer_flags & URB_ZERO_PACKET) &&
684 	    usb_pipeout(urb->pipe) && !(remaining % maxps);
685 
686 	while (remaining || need_empty) {
687 		int len;
688 		char *td_buf;
689 
690 		len = (remaining > maxps) ? maxps : remaining;
691 		if (!len)
692 			need_empty = 0;
693 
694 		pid = usb_pipeout(urb->pipe) ? USB_PID_OUT : USB_PID_IN;
695 		td_buf = urb->transfer_buffer + urb->transfer_buffer_length -
696 		    remaining;
697 		ret = c67x00_create_td(c67x00, urb, td_buf, len, pid, toggle,
698 				       DATA_STAGE);
699 		if (ret)
700 			return ret;	/* td wasn't created */
701 
702 		toggle ^= 1;
703 		remaining -= len;
704 		if (usb_pipecontrol(urb->pipe))
705 			break;
706 	}
707 
708 	return 0;
709 }
710 
711 /**
712  * return 0 in case more bandwidth is available, else errorcode
713  */
714 static int c67x00_add_ctrl_urb(struct c67x00_hcd *c67x00, struct urb *urb)
715 {
716 	int ret;
717 	int pid;
718 
719 	switch (urb->interval) {
720 	default:
721 	case SETUP_STAGE:
722 		ret = c67x00_create_td(c67x00, urb, urb->setup_packet,
723 				       8, USB_PID_SETUP, 0, SETUP_STAGE);
724 		if (ret)
725 			return ret;
726 		urb->interval = SETUP_STAGE;
727 		usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe),
728 			      usb_pipeout(urb->pipe), 1);
729 		break;
730 	case DATA_STAGE:
731 		if (urb->transfer_buffer_length) {
732 			ret = c67x00_add_data_urb(c67x00, urb);
733 			if (ret)
734 				return ret;
735 			break;
736 		}		/* else fallthrough */
737 	case STATUS_STAGE:
738 		pid = !usb_pipeout(urb->pipe) ? USB_PID_OUT : USB_PID_IN;
739 		ret = c67x00_create_td(c67x00, urb, NULL, 0, pid, 1,
740 				       STATUS_STAGE);
741 		if (ret)
742 			return ret;
743 		break;
744 	}
745 
746 	return 0;
747 }
748 
749 /*
750  * return 0 in case more bandwidth is available, else errorcode
751  */
752 static int c67x00_add_int_urb(struct c67x00_hcd *c67x00, struct urb *urb)
753 {
754 	struct c67x00_urb_priv *urbp = urb->hcpriv;
755 
756 	if (frame_after_eq(c67x00->current_frame, urbp->ep_data->next_frame)) {
757 		urbp->ep_data->next_frame =
758 		    frame_add(urbp->ep_data->next_frame, urb->interval);
759 		return c67x00_add_data_urb(c67x00, urb);
760 	}
761 	return 0;
762 }
763 
764 static int c67x00_add_iso_urb(struct c67x00_hcd *c67x00, struct urb *urb)
765 {
766 	struct c67x00_urb_priv *urbp = urb->hcpriv;
767 
768 	if (frame_after_eq(c67x00->current_frame, urbp->ep_data->next_frame)) {
769 		char *td_buf;
770 		int len, pid, ret;
771 
772 		BUG_ON(urbp->cnt >= urb->number_of_packets);
773 
774 		td_buf = urb->transfer_buffer +
775 		    urb->iso_frame_desc[urbp->cnt].offset;
776 		len = urb->iso_frame_desc[urbp->cnt].length;
777 		pid = usb_pipeout(urb->pipe) ? USB_PID_OUT : USB_PID_IN;
778 
779 		ret = c67x00_create_td(c67x00, urb, td_buf, len, pid, 0,
780 				       urbp->cnt);
781 		if (ret) {
782 			printk(KERN_DEBUG "create failed: %d\n", ret);
783 			urb->iso_frame_desc[urbp->cnt].actual_length = 0;
784 			urb->iso_frame_desc[urbp->cnt].status = ret;
785 			if (urbp->cnt + 1 == urb->number_of_packets)
786 				c67x00_giveback_urb(c67x00, urb, 0);
787 		}
788 
789 		urbp->ep_data->next_frame =
790 		    frame_add(urbp->ep_data->next_frame, urb->interval);
791 		urbp->cnt++;
792 	}
793 	return 0;
794 }
795 
796 /* -------------------------------------------------------------------------- */
797 
798 static void c67x00_fill_from_list(struct c67x00_hcd *c67x00, int type,
799 				  int (*add)(struct c67x00_hcd *, struct urb *))
800 {
801 	struct c67x00_ep_data *ep_data;
802 	struct urb *urb;
803 
804 	/* traverse every endpoint on the list */
805 	list_for_each_entry(ep_data, &c67x00->list[type], node) {
806 		if (!list_empty(&ep_data->queue)) {
807 			/* and add the first urb */
808 			/* isochronous transfer rely on this */
809 			urb = list_entry(ep_data->queue.next,
810 					 struct c67x00_urb_priv,
811 					 hep_node)->urb;
812 			add(c67x00, urb);
813 		}
814 	}
815 }
816 
817 static void c67x00_fill_frame(struct c67x00_hcd *c67x00)
818 {
819 	struct c67x00_td *td, *ttd;
820 
821 	/* Check if we can proceed */
822 	if (!list_empty(&c67x00->td_list)) {
823 		dev_warn(c67x00_hcd_dev(c67x00),
824 			 "TD list not empty! This should not happen!\n");
825 		list_for_each_entry_safe(td, ttd, &c67x00->td_list, td_list) {
826 			dbg_td(c67x00, td, "Unprocessed td");
827 			c67x00_release_td(td);
828 		}
829 	}
830 
831 	/* Reinitialize variables */
832 	c67x00->bandwidth_allocated = 0;
833 	c67x00->periodic_bw_allocated = 0;
834 
835 	c67x00->next_td_addr = c67x00->td_base_addr;
836 	c67x00->next_buf_addr = c67x00->buf_base_addr;
837 
838 	/* Fill the list */
839 	c67x00_fill_from_list(c67x00, PIPE_ISOCHRONOUS, c67x00_add_iso_urb);
840 	c67x00_fill_from_list(c67x00, PIPE_INTERRUPT, c67x00_add_int_urb);
841 	c67x00_fill_from_list(c67x00, PIPE_CONTROL, c67x00_add_ctrl_urb);
842 	c67x00_fill_from_list(c67x00, PIPE_BULK, c67x00_add_data_urb);
843 }
844 
845 /* -------------------------------------------------------------------------- */
846 
847 /**
848  * Get TD from C67X00
849  */
850 static inline void
851 c67x00_parse_td(struct c67x00_hcd *c67x00, struct c67x00_td *td)
852 {
853 	c67x00_ll_read_mem_le16(c67x00->sie->dev,
854 				td->td_addr, td, CY_TD_SIZE);
855 
856 	if (usb_pipein(td->pipe) && td_actual_bytes(td))
857 		c67x00_ll_read_mem_le16(c67x00->sie->dev, td_ly_base_addr(td),
858 					td->data, td_actual_bytes(td));
859 }
860 
861 static int c67x00_td_to_error(struct c67x00_hcd *c67x00, struct c67x00_td *td)
862 {
863 	if (td->status & TD_STATUSMASK_ERR) {
864 		dbg_td(c67x00, td, "ERROR_FLAG");
865 		return -EILSEQ;
866 	}
867 	if (td->status & TD_STATUSMASK_STALL) {
868 		/* dbg_td(c67x00, td, "STALL"); */
869 		return -EPIPE;
870 	}
871 	if (td->status & TD_STATUSMASK_TMOUT) {
872 		dbg_td(c67x00, td, "TIMEOUT");
873 		return -ETIMEDOUT;
874 	}
875 
876 	return 0;
877 }
878 
879 static inline int c67x00_end_of_data(struct c67x00_td *td)
880 {
881 	int maxps, need_empty, remaining;
882 	struct urb *urb = td->urb;
883 	int act_bytes;
884 
885 	act_bytes = td_actual_bytes(td);
886 
887 	if (unlikely(!act_bytes))
888 		return 1;	/* This was an empty packet */
889 
890 	maxps = usb_maxpacket(td_udev(td), td->pipe, usb_pipeout(td->pipe));
891 
892 	if (unlikely(act_bytes < maxps))
893 		return 1;	/* Smaller then full packet */
894 
895 	remaining = urb->transfer_buffer_length - urb->actual_length;
896 	need_empty = (urb->transfer_flags & URB_ZERO_PACKET) &&
897 	    usb_pipeout(urb->pipe) && !(remaining % maxps);
898 
899 	if (unlikely(!remaining && !need_empty))
900 		return 1;
901 
902 	return 0;
903 }
904 
905 /* -------------------------------------------------------------------------- */
906 
907 /* Remove all td's from the list which come
908  * after last_td and are meant for the same pipe.
909  * This is used when a short packet has occured */
910 static inline void c67x00_clear_pipe(struct c67x00_hcd *c67x00,
911 				     struct c67x00_td *last_td)
912 {
913 	struct c67x00_td *td, *tmp;
914 	td = last_td;
915 	tmp = last_td;
916 	while (td->td_list.next != &c67x00->td_list) {
917 		td = list_entry(td->td_list.next, struct c67x00_td, td_list);
918 		if (td->pipe == last_td->pipe) {
919 			c67x00_release_td(td);
920 			td = tmp;
921 		}
922 		tmp = td;
923 	}
924 }
925 
926 /* -------------------------------------------------------------------------- */
927 
928 static void c67x00_handle_successful_td(struct c67x00_hcd *c67x00,
929 					struct c67x00_td *td)
930 {
931 	struct urb *urb = td->urb;
932 
933 	if (!urb)
934 		return;
935 
936 	urb->actual_length += td_actual_bytes(td);
937 
938 	switch (usb_pipetype(td->pipe)) {
939 		/* isochronous tds are handled separately */
940 	case PIPE_CONTROL:
941 		switch (td->privdata) {
942 		case SETUP_STAGE:
943 			urb->interval =
944 			    urb->transfer_buffer_length ?
945 			    DATA_STAGE : STATUS_STAGE;
946 			/* Don't count setup_packet with normal data: */
947 			urb->actual_length = 0;
948 			break;
949 
950 		case DATA_STAGE:
951 			if (c67x00_end_of_data(td)) {
952 				urb->interval = STATUS_STAGE;
953 				c67x00_clear_pipe(c67x00, td);
954 			}
955 			break;
956 
957 		case STATUS_STAGE:
958 			urb->interval = 0;
959 			c67x00_giveback_urb(c67x00, urb, 0);
960 			break;
961 		}
962 		break;
963 
964 	case PIPE_INTERRUPT:
965 	case PIPE_BULK:
966 		if (unlikely(c67x00_end_of_data(td))) {
967 			c67x00_clear_pipe(c67x00, td);
968 			c67x00_giveback_urb(c67x00, urb, 0);
969 		}
970 		break;
971 	}
972 }
973 
974 static void c67x00_handle_isoc(struct c67x00_hcd *c67x00, struct c67x00_td *td)
975 {
976 	struct urb *urb = td->urb;
977 	struct c67x00_urb_priv *urbp;
978 	int cnt;
979 
980 	if (!urb)
981 		return;
982 
983 	urbp = urb->hcpriv;
984 	cnt = td->privdata;
985 
986 	if (td->status & TD_ERROR_MASK)
987 		urb->error_count++;
988 
989 	urb->iso_frame_desc[cnt].actual_length = td_actual_bytes(td);
990 	urb->iso_frame_desc[cnt].status = c67x00_td_to_error(c67x00, td);
991 	if (cnt + 1 == urb->number_of_packets)	/* Last packet */
992 		c67x00_giveback_urb(c67x00, urb, 0);
993 }
994 
995 /* -------------------------------------------------------------------------- */
996 
997 /**
998  * c67x00_check_td_list - handle tds which have been processed by the c67x00
999  * pre: current_td == 0
1000  */
1001 static inline void c67x00_check_td_list(struct c67x00_hcd *c67x00)
1002 {
1003 	struct c67x00_td *td, *tmp;
1004 	struct urb *urb;
1005 	int ack_ok;
1006 	int clear_endpoint;
1007 
1008 	list_for_each_entry_safe(td, tmp, &c67x00->td_list, td_list) {
1009 		/* get the TD */
1010 		c67x00_parse_td(c67x00, td);
1011 		urb = td->urb;	/* urb can be NULL! */
1012 		ack_ok = 0;
1013 		clear_endpoint = 1;
1014 
1015 		/* Handle isochronous transfers separately */
1016 		if (usb_pipeisoc(td->pipe)) {
1017 			clear_endpoint = 0;
1018 			c67x00_handle_isoc(c67x00, td);
1019 			goto cont;
1020 		}
1021 
1022 		/* When an error occurs, all td's for that pipe go into an
1023 		 * inactive state. This state matches successful transfers so
1024 		 * we must make sure not to service them. */
1025 		if (td->status & TD_ERROR_MASK) {
1026 			c67x00_giveback_urb(c67x00, urb,
1027 					    c67x00_td_to_error(c67x00, td));
1028 			goto cont;
1029 		}
1030 
1031 		if ((td->status & TD_STATUSMASK_NAK) || !td_sequence_ok(td) ||
1032 		    !td_acked(td))
1033 			goto cont;
1034 
1035 		/* Sequence ok and acked, don't need to fix toggle */
1036 		ack_ok = 1;
1037 
1038 		if (unlikely(td->status & TD_STATUSMASK_OVF)) {
1039 			if (td_residue(td) & TD_RESIDUE_OVERFLOW) {
1040 				/* Overflow */
1041 				c67x00_giveback_urb(c67x00, urb, -EOVERFLOW);
1042 				goto cont;
1043 			}
1044 		}
1045 
1046 		clear_endpoint = 0;
1047 		c67x00_handle_successful_td(c67x00, td);
1048 
1049 cont:
1050 		if (clear_endpoint)
1051 			c67x00_clear_pipe(c67x00, td);
1052 		if (ack_ok)
1053 			usb_settoggle(td_udev(td), usb_pipeendpoint(td->pipe),
1054 				      usb_pipeout(td->pipe),
1055 				      !(td->ctrl_reg & SEQ_SEL));
1056 		/* next in list could have been removed, due to clear_pipe! */
1057 		tmp = list_entry(td->td_list.next, typeof(*td), td_list);
1058 		c67x00_release_td(td);
1059 	}
1060 }
1061 
1062 /* -------------------------------------------------------------------------- */
1063 
1064 static inline int c67x00_all_tds_processed(struct c67x00_hcd *c67x00)
1065 {
1066 	/* If all tds are processed, we can check the previous frame (if
1067 	 * there was any) and start our next frame.
1068 	 */
1069 	return !c67x00_ll_husb_get_current_td(c67x00->sie);
1070 }
1071 
1072 /**
1073  * Send td to C67X00
1074  */
1075 static void c67x00_send_td(struct c67x00_hcd *c67x00, struct c67x00_td *td)
1076 {
1077 	int len = td_length(td);
1078 
1079 	if (len && ((td->pid_ep & TD_PIDEPMASK_PID) != TD_PID_IN))
1080 		c67x00_ll_write_mem_le16(c67x00->sie->dev, td_ly_base_addr(td),
1081 					 td->data, len);
1082 
1083 	c67x00_ll_write_mem_le16(c67x00->sie->dev,
1084 				 td->td_addr, td, CY_TD_SIZE);
1085 }
1086 
1087 static void c67x00_send_frame(struct c67x00_hcd *c67x00)
1088 {
1089 	struct c67x00_td *td;
1090 
1091 	if (list_empty(&c67x00->td_list))
1092 		dev_warn(c67x00_hcd_dev(c67x00),
1093 			 "%s: td list should not be empty here!\n",
1094 			 __func__);
1095 
1096 	list_for_each_entry(td, &c67x00->td_list, td_list) {
1097 		if (td->td_list.next == &c67x00->td_list)
1098 			td->next_td_addr = 0;	/* Last td in list */
1099 
1100 		c67x00_send_td(c67x00, td);
1101 	}
1102 
1103 	c67x00_ll_husb_set_current_td(c67x00->sie, c67x00->td_base_addr);
1104 }
1105 
1106 /* -------------------------------------------------------------------------- */
1107 
1108 /**
1109  * c67x00_do_work - Schedulers state machine
1110  */
1111 static void c67x00_do_work(struct c67x00_hcd *c67x00)
1112 {
1113 	spin_lock(&c67x00->lock);
1114 	/* Make sure all tds are processed */
1115 	if (!c67x00_all_tds_processed(c67x00))
1116 		goto out;
1117 
1118 	c67x00_check_td_list(c67x00);
1119 
1120 	/* no td's are being processed (current == 0)
1121 	 * and all have been "checked" */
1122 	complete(&c67x00->endpoint_disable);
1123 
1124 	if (!list_empty(&c67x00->td_list))
1125 		goto out;
1126 
1127 	c67x00->current_frame = c67x00_get_current_frame_number(c67x00);
1128 	if (c67x00->current_frame == c67x00->last_frame)
1129 		goto out;	/* Don't send tds in same frame */
1130 	c67x00->last_frame = c67x00->current_frame;
1131 
1132 	/* If no urbs are scheduled, our work is done */
1133 	if (!c67x00->urb_count) {
1134 		c67x00_ll_hpi_disable_sofeop(c67x00->sie);
1135 		goto out;
1136 	}
1137 
1138 	c67x00_fill_frame(c67x00);
1139 	if (!list_empty(&c67x00->td_list))
1140 		/* TD's have been added to the frame */
1141 		c67x00_send_frame(c67x00);
1142 
1143  out:
1144 	spin_unlock(&c67x00->lock);
1145 }
1146 
1147 /* -------------------------------------------------------------------------- */
1148 
1149 static void c67x00_sched_tasklet(unsigned long __c67x00)
1150 {
1151 	struct c67x00_hcd *c67x00 = (struct c67x00_hcd *)__c67x00;
1152 	c67x00_do_work(c67x00);
1153 }
1154 
1155 void c67x00_sched_kick(struct c67x00_hcd *c67x00)
1156 {
1157 	tasklet_hi_schedule(&c67x00->tasklet);
1158 }
1159 
1160 int c67x00_sched_start_scheduler(struct c67x00_hcd *c67x00)
1161 {
1162 	tasklet_init(&c67x00->tasklet, c67x00_sched_tasklet,
1163 		     (unsigned long)c67x00);
1164 	return 0;
1165 }
1166 
1167 void c67x00_sched_stop_scheduler(struct c67x00_hcd *c67x00)
1168 {
1169 	tasklet_kill(&c67x00->tasklet);
1170 }
1171