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#include <linux/slab.h>
26
27#include "c67x00.h"
28#include "c67x00-hcd.h"
29
30/*
31 * These are the stages for a control urb, they are kept
32 * in both urb->interval and td->privdata.
33 */
34#define SETUP_STAGE		0
35#define DATA_STAGE		1
36#define STATUS_STAGE		2
37
38/* -------------------------------------------------------------------------- */
39
40/**
41 * struct c67x00_ep_data: Host endpoint data structure
42 */
43struct c67x00_ep_data {
44	struct list_head queue;
45	struct list_head node;
46	struct usb_host_endpoint *hep;
47	struct usb_device *dev;
48	u16 next_frame;		/* For int/isoc transactions */
49};
50
51/**
52 * struct c67x00_td
53 *
54 * Hardware parts are little endiannes, SW in CPU endianess.
55 */
56struct c67x00_td {
57	/* HW specific part */
58	__le16 ly_base_addr;	/* Bytes 0-1 */
59	__le16 port_length;	/* Bytes 2-3 */
60	u8 pid_ep;		/* Byte 4 */
61	u8 dev_addr;		/* Byte 5 */
62	u8 ctrl_reg;		/* Byte 6 */
63	u8 status;		/* Byte 7 */
64	u8 retry_cnt;		/* Byte 8 */
65#define TT_OFFSET		2
66#define TT_CONTROL		0
67#define TT_ISOCHRONOUS		1
68#define TT_BULK			2
69#define TT_INTERRUPT		3
70	u8 residue;		/* Byte 9 */
71	__le16 next_td_addr;	/* Bytes 10-11 */
72	/* SW part */
73	struct list_head td_list;
74	u16 td_addr;
75	void *data;
76	struct urb *urb;
77	unsigned long privdata;
78
79	/* These are needed for handling the toggle bits:
80	 * an urb can be dequeued while a td is in progress
81	 * after checking the td, the toggle bit might need to
82	 * be fixed */
83	struct c67x00_ep_data *ep_data;
84	unsigned int pipe;
85};
86
87struct c67x00_urb_priv {
88	struct list_head hep_node;
89	struct urb *urb;
90	int port;
91	int cnt;		/* packet number for isoc */
92	int status;
93	struct c67x00_ep_data *ep_data;
94};
95
96#define td_udev(td)	((td)->ep_data->dev)
97
98#define CY_TD_SIZE		12
99
100#define TD_PIDEP_OFFSET		0x04
101#define TD_PIDEPMASK_PID	0xF0
102#define TD_PIDEPMASK_EP		0x0F
103#define TD_PORTLENMASK_DL	0x03FF
104#define TD_PORTLENMASK_PN	0xC000
105
106#define TD_STATUS_OFFSET	0x07
107#define TD_STATUSMASK_ACK	0x01
108#define TD_STATUSMASK_ERR	0x02
109#define TD_STATUSMASK_TMOUT	0x04
110#define TD_STATUSMASK_SEQ	0x08
111#define TD_STATUSMASK_SETUP	0x10
112#define TD_STATUSMASK_OVF	0x20
113#define TD_STATUSMASK_NAK	0x40
114#define TD_STATUSMASK_STALL	0x80
115
116#define TD_ERROR_MASK		(TD_STATUSMASK_ERR | TD_STATUSMASK_TMOUT | \
117				 TD_STATUSMASK_STALL)
118
119#define TD_RETRYCNT_OFFSET	0x08
120#define TD_RETRYCNTMASK_ACT_FLG	0x10
121#define TD_RETRYCNTMASK_TX_TYPE	0x0C
122#define TD_RETRYCNTMASK_RTY_CNT	0x03
123
124#define TD_RESIDUE_OVERFLOW	0x80
125
126#define TD_PID_IN		0x90
127
128/* Residue: signed 8bits, neg -> OVERFLOW, pos -> UNDERFLOW */
129#define td_residue(td)		((__s8)(td->residue))
130#define td_ly_base_addr(td)	(__le16_to_cpu((td)->ly_base_addr))
131#define td_port_length(td)	(__le16_to_cpu((td)->port_length))
132#define td_next_td_addr(td)	(__le16_to_cpu((td)->next_td_addr))
133
134#define td_active(td)		((td)->retry_cnt & TD_RETRYCNTMASK_ACT_FLG)
135#define td_length(td)		(td_port_length(td) & TD_PORTLENMASK_DL)
136
137#define td_sequence_ok(td)	(!td->status || \
138				 (!(td->status & TD_STATUSMASK_SEQ) ==	\
139				  !(td->ctrl_reg & SEQ_SEL)))
140
141#define td_acked(td)		(!td->status || \
142				 (td->status & TD_STATUSMASK_ACK))
143#define td_actual_bytes(td)	(td_length(td) - td_residue(td))
144
145/* -------------------------------------------------------------------------- */
146
147/**
148 * dbg_td - Dump the contents of the TD
149 */
150static void dbg_td(struct c67x00_hcd *c67x00, struct c67x00_td *td, char *msg)
151{
152	struct device *dev = c67x00_hcd_dev(c67x00);
153
154	dev_dbg(dev, "### %s at 0x%04x\n", msg, td->td_addr);
155	dev_dbg(dev, "urb:      0x%p\n", td->urb);
156	dev_dbg(dev, "endpoint:   %4d\n", usb_pipeendpoint(td->pipe));
157	dev_dbg(dev, "pipeout:    %4d\n", usb_pipeout(td->pipe));
158	dev_dbg(dev, "ly_base_addr: 0x%04x\n", td_ly_base_addr(td));
159	dev_dbg(dev, "port_length:  0x%04x\n", td_port_length(td));
160	dev_dbg(dev, "pid_ep:         0x%02x\n", td->pid_ep);
161	dev_dbg(dev, "dev_addr:       0x%02x\n", td->dev_addr);
162	dev_dbg(dev, "ctrl_reg:       0x%02x\n", td->ctrl_reg);
163	dev_dbg(dev, "status:         0x%02x\n", td->status);
164	dev_dbg(dev, "retry_cnt:      0x%02x\n", td->retry_cnt);
165	dev_dbg(dev, "residue:        0x%02x\n", td->residue);
166	dev_dbg(dev, "next_td_addr: 0x%04x\n", td_next_td_addr(td));
167	dev_dbg(dev, "data: %*ph\n", td_length(td), td->data);
168}
169
170/* -------------------------------------------------------------------------- */
171/* Helper functions */
172
173static inline u16 c67x00_get_current_frame_number(struct c67x00_hcd *c67x00)
174{
175	return c67x00_ll_husb_get_frame(c67x00->sie) & HOST_FRAME_MASK;
176}
177
178/**
179 * frame_add
180 * Software wraparound for framenumbers.
181 */
182static inline u16 frame_add(u16 a, u16 b)
183{
184	return (a + b) & HOST_FRAME_MASK;
185}
186
187/**
188 * frame_after - is frame a after frame b
189 */
190static inline int frame_after(u16 a, u16 b)
191{
192	return ((HOST_FRAME_MASK + a - b) & HOST_FRAME_MASK) <
193	    (HOST_FRAME_MASK / 2);
194}
195
196/**
197 * frame_after_eq - is frame a after or equal to frame b
198 */
199static inline int frame_after_eq(u16 a, u16 b)
200{
201	return ((HOST_FRAME_MASK + 1 + a - b) & HOST_FRAME_MASK) <
202	    (HOST_FRAME_MASK / 2);
203}
204
205/* -------------------------------------------------------------------------- */
206
207/**
208 * c67x00_release_urb - remove link from all tds to this urb
209 * Disconnects the urb from it's tds, so that it can be given back.
210 * pre: urb->hcpriv != NULL
211 */
212static void c67x00_release_urb(struct c67x00_hcd *c67x00, struct urb *urb)
213{
214	struct c67x00_td *td;
215	struct c67x00_urb_priv *urbp;
216
217	BUG_ON(!urb);
218
219	c67x00->urb_count--;
220
221	if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) {
222		c67x00->urb_iso_count--;
223		if (c67x00->urb_iso_count == 0)
224			c67x00->max_frame_bw = MAX_FRAME_BW_STD;
225	}
226
227	/* TODO this might be not so efficient when we've got many urbs!
228	 * Alternatives:
229	 *   * only clear when needed
230	 *   * keep a list of tds with each urbp
231	 */
232	list_for_each_entry(td, &c67x00->td_list, td_list)
233		if (urb == td->urb)
234			td->urb = NULL;
235
236	urbp = urb->hcpriv;
237	urb->hcpriv = NULL;
238	list_del(&urbp->hep_node);
239	kfree(urbp);
240}
241
242/* -------------------------------------------------------------------------- */
243
244static struct c67x00_ep_data *
245c67x00_ep_data_alloc(struct c67x00_hcd *c67x00, struct urb *urb)
246{
247	struct usb_host_endpoint *hep = urb->ep;
248	struct c67x00_ep_data *ep_data;
249	int type;
250
251	c67x00->current_frame = c67x00_get_current_frame_number(c67x00);
252
253	/* Check if endpoint already has a c67x00_ep_data struct allocated */
254	if (hep->hcpriv) {
255		ep_data = hep->hcpriv;
256		if (frame_after(c67x00->current_frame, ep_data->next_frame))
257			ep_data->next_frame =
258			    frame_add(c67x00->current_frame, 1);
259		return hep->hcpriv;
260	}
261
262	/* Allocate and initialize a new c67x00 endpoint data structure */
263	ep_data = kzalloc(sizeof(*ep_data), GFP_ATOMIC);
264	if (!ep_data)
265		return NULL;
266
267	INIT_LIST_HEAD(&ep_data->queue);
268	INIT_LIST_HEAD(&ep_data->node);
269	ep_data->hep = hep;
270
271	/* hold a reference to udev as long as this endpoint lives,
272	 * this is needed to possibly fix the data toggle */
273	ep_data->dev = usb_get_dev(urb->dev);
274	hep->hcpriv = ep_data;
275
276	/* For ISOC and INT endpoints, start ASAP: */
277	ep_data->next_frame = frame_add(c67x00->current_frame, 1);
278
279	/* Add the endpoint data to one of the pipe lists; must be added
280	   in order of endpoint address */
281	type = usb_pipetype(urb->pipe);
282	if (list_empty(&ep_data->node)) {
283		list_add(&ep_data->node, &c67x00->list[type]);
284	} else {
285		struct c67x00_ep_data *prev;
286
287		list_for_each_entry(prev, &c67x00->list[type], node) {
288			if (prev->hep->desc.bEndpointAddress >
289			    hep->desc.bEndpointAddress) {
290				list_add(&ep_data->node, prev->node.prev);
291				break;
292			}
293		}
294	}
295
296	return ep_data;
297}
298
299static int c67x00_ep_data_free(struct usb_host_endpoint *hep)
300{
301	struct c67x00_ep_data *ep_data = hep->hcpriv;
302
303	if (!ep_data)
304		return 0;
305
306	if (!list_empty(&ep_data->queue))
307		return -EBUSY;
308
309	usb_put_dev(ep_data->dev);
310	list_del(&ep_data->queue);
311	list_del(&ep_data->node);
312
313	kfree(ep_data);
314	hep->hcpriv = NULL;
315
316	return 0;
317}
318
319void c67x00_endpoint_disable(struct usb_hcd *hcd, struct usb_host_endpoint *ep)
320{
321	struct c67x00_hcd *c67x00 = hcd_to_c67x00_hcd(hcd);
322	unsigned long flags;
323
324	if (!list_empty(&ep->urb_list))
325		dev_warn(c67x00_hcd_dev(c67x00), "error: urb list not empty\n");
326
327	spin_lock_irqsave(&c67x00->lock, flags);
328
329	/* loop waiting for all transfers in the endpoint queue to complete */
330	while (c67x00_ep_data_free(ep)) {
331		/* Drop the lock so we can sleep waiting for the hardware */
332		spin_unlock_irqrestore(&c67x00->lock, flags);
333
334		/* it could happen that we reinitialize this completion, while
335		 * somebody was waiting for that completion.  The timeout and
336		 * while loop handle such cases, but this might be improved */
337		reinit_completion(&c67x00->endpoint_disable);
338		c67x00_sched_kick(c67x00);
339		wait_for_completion_timeout(&c67x00->endpoint_disable, 1 * HZ);
340
341		spin_lock_irqsave(&c67x00->lock, flags);
342	}
343
344	spin_unlock_irqrestore(&c67x00->lock, flags);
345}
346
347/* -------------------------------------------------------------------------- */
348
349static inline int get_root_port(struct usb_device *dev)
350{
351	while (dev->parent->parent)
352		dev = dev->parent;
353	return dev->portnum;
354}
355
356int c67x00_urb_enqueue(struct usb_hcd *hcd,
357		       struct urb *urb, gfp_t mem_flags)
358{
359	int ret;
360	unsigned long flags;
361	struct c67x00_urb_priv *urbp;
362	struct c67x00_hcd *c67x00 = hcd_to_c67x00_hcd(hcd);
363	int port = get_root_port(urb->dev)-1;
364
365	/* Allocate and initialize urb private data */
366	urbp = kzalloc(sizeof(*urbp), mem_flags);
367	if (!urbp) {
368		ret = -ENOMEM;
369		goto err_urbp;
370	}
371
372	spin_lock_irqsave(&c67x00->lock, flags);
373
374	/* Make sure host controller is running */
375	if (!HC_IS_RUNNING(hcd->state)) {
376		ret = -ENODEV;
377		goto err_not_linked;
378	}
379
380	ret = usb_hcd_link_urb_to_ep(hcd, urb);
381	if (ret)
382		goto err_not_linked;
383
384	INIT_LIST_HEAD(&urbp->hep_node);
385	urbp->urb = urb;
386	urbp->port = port;
387
388	urbp->ep_data = c67x00_ep_data_alloc(c67x00, urb);
389
390	if (!urbp->ep_data) {
391		ret = -ENOMEM;
392		goto err_epdata;
393	}
394
395	/* TODO claim bandwidth with usb_claim_bandwidth?
396	 * also release it somewhere! */
397
398	urb->hcpriv = urbp;
399
400	urb->actual_length = 0;	/* Nothing received/transmitted yet */
401
402	switch (usb_pipetype(urb->pipe)) {
403	case PIPE_CONTROL:
404		urb->interval = SETUP_STAGE;
405		break;
406	case PIPE_INTERRUPT:
407		break;
408	case PIPE_BULK:
409		break;
410	case PIPE_ISOCHRONOUS:
411		if (c67x00->urb_iso_count == 0)
412			c67x00->max_frame_bw = MAX_FRAME_BW_ISO;
413		c67x00->urb_iso_count++;
414		/* Assume always URB_ISO_ASAP, FIXME */
415		if (list_empty(&urbp->ep_data->queue))
416			urb->start_frame = urbp->ep_data->next_frame;
417		else {
418			/* Go right after the last one */
419			struct urb *last_urb;
420
421			last_urb = list_entry(urbp->ep_data->queue.prev,
422					      struct c67x00_urb_priv,
423					      hep_node)->urb;
424			urb->start_frame =
425			    frame_add(last_urb->start_frame,
426				      last_urb->number_of_packets *
427				      last_urb->interval);
428		}
429		urbp->cnt = 0;
430		break;
431	}
432
433	/* Add the URB to the endpoint queue */
434	list_add_tail(&urbp->hep_node, &urbp->ep_data->queue);
435
436	/* If this is the only URB, kick start the controller */
437	if (!c67x00->urb_count++)
438		c67x00_ll_hpi_enable_sofeop(c67x00->sie);
439
440	c67x00_sched_kick(c67x00);
441	spin_unlock_irqrestore(&c67x00->lock, flags);
442
443	return 0;
444
445err_epdata:
446	usb_hcd_unlink_urb_from_ep(hcd, urb);
447err_not_linked:
448	spin_unlock_irqrestore(&c67x00->lock, flags);
449	kfree(urbp);
450err_urbp:
451
452	return ret;
453}
454
455int c67x00_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
456{
457	struct c67x00_hcd *c67x00 = hcd_to_c67x00_hcd(hcd);
458	unsigned long flags;
459	int rc;
460
461	spin_lock_irqsave(&c67x00->lock, flags);
462	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
463	if (rc)
464		goto done;
465
466	c67x00_release_urb(c67x00, urb);
467	usb_hcd_unlink_urb_from_ep(hcd, urb);
468
469	spin_unlock(&c67x00->lock);
470	usb_hcd_giveback_urb(hcd, urb, status);
471	spin_lock(&c67x00->lock);
472
473	spin_unlock_irqrestore(&c67x00->lock, flags);
474
475	return 0;
476
477 done:
478	spin_unlock_irqrestore(&c67x00->lock, flags);
479	return rc;
480}
481
482/* -------------------------------------------------------------------------- */
483
484/*
485 * pre: c67x00 locked, urb unlocked
486 */
487static void
488c67x00_giveback_urb(struct c67x00_hcd *c67x00, struct urb *urb, int status)
489{
490	struct c67x00_urb_priv *urbp;
491
492	if (!urb)
493		return;
494
495	urbp = urb->hcpriv;
496	urbp->status = status;
497
498	list_del_init(&urbp->hep_node);
499
500	c67x00_release_urb(c67x00, urb);
501	usb_hcd_unlink_urb_from_ep(c67x00_hcd_to_hcd(c67x00), urb);
502	spin_unlock(&c67x00->lock);
503	usb_hcd_giveback_urb(c67x00_hcd_to_hcd(c67x00), urb, urbp->status);
504	spin_lock(&c67x00->lock);
505}
506
507/* -------------------------------------------------------------------------- */
508
509static int c67x00_claim_frame_bw(struct c67x00_hcd *c67x00, struct urb *urb,
510				 int len, int periodic)
511{
512	struct c67x00_urb_priv *urbp = urb->hcpriv;
513	int bit_time;
514
515	/* According to the C67x00 BIOS user manual, page 3-18,19, the
516	 * following calculations provide the full speed bit times for
517	 * a transaction.
518	 *
519	 * FS(in)	= 112.5 +  9.36*BC + HOST_DELAY
520	 * FS(in,iso)	=  90.5 +  9.36*BC + HOST_DELAY
521	 * FS(out)	= 112.5 +  9.36*BC + HOST_DELAY
522	 * FS(out,iso)	=  78.4 +  9.36*BC + HOST_DELAY
523	 * LS(in)	= 802.4 + 75.78*BC + HOST_DELAY
524	 * LS(out)	= 802.6 + 74.67*BC + HOST_DELAY
525	 *
526	 * HOST_DELAY == 106 for the c67200 and c67300.
527	 */
528
529	/* make calculations in 1/100 bit times to maintain resolution */
530	if (urbp->ep_data->dev->speed == USB_SPEED_LOW) {
531		/* Low speed pipe */
532		if (usb_pipein(urb->pipe))
533			bit_time = 80240 + 7578*len;
534		else
535			bit_time = 80260 + 7467*len;
536	} else {
537		/* FS pipes */
538		if (usb_pipeisoc(urb->pipe))
539			bit_time = usb_pipein(urb->pipe) ? 9050 : 7840;
540		else
541			bit_time = 11250;
542		bit_time += 936*len;
543	}
544
545	/* Scale back down to integer bit times.  Use a host delay of 106.
546	 * (this is the only place it is used) */
547	bit_time = ((bit_time+50) / 100) + 106;
548
549	if (unlikely(bit_time + c67x00->bandwidth_allocated >=
550		     c67x00->max_frame_bw))
551		return -EMSGSIZE;
552
553	if (unlikely(c67x00->next_td_addr + CY_TD_SIZE >=
554		     c67x00->td_base_addr + SIE_TD_SIZE))
555		return -EMSGSIZE;
556
557	if (unlikely(c67x00->next_buf_addr + len >=
558		     c67x00->buf_base_addr + SIE_TD_BUF_SIZE))
559		return -EMSGSIZE;
560
561	if (periodic) {
562		if (unlikely(bit_time + c67x00->periodic_bw_allocated >=
563			     MAX_PERIODIC_BW(c67x00->max_frame_bw)))
564			return -EMSGSIZE;
565		c67x00->periodic_bw_allocated += bit_time;
566	}
567
568	c67x00->bandwidth_allocated += bit_time;
569	return 0;
570}
571
572/* -------------------------------------------------------------------------- */
573
574/**
575 * td_addr and buf_addr must be word aligned
576 */
577static int c67x00_create_td(struct c67x00_hcd *c67x00, struct urb *urb,
578			    void *data, int len, int pid, int toggle,
579			    unsigned long privdata)
580{
581	struct c67x00_td *td;
582	struct c67x00_urb_priv *urbp = urb->hcpriv;
583	const __u8 active_flag = 1, retry_cnt = 3;
584	__u8 cmd = 0;
585	int tt = 0;
586
587	if (c67x00_claim_frame_bw(c67x00, urb, len, usb_pipeisoc(urb->pipe)
588				  || usb_pipeint(urb->pipe)))
589		return -EMSGSIZE;	/* Not really an error, but expected */
590
591	td = kzalloc(sizeof(*td), GFP_ATOMIC);
592	if (!td)
593		return -ENOMEM;
594
595	td->pipe = urb->pipe;
596	td->ep_data = urbp->ep_data;
597
598	if ((td_udev(td)->speed == USB_SPEED_LOW) &&
599	    !(c67x00->low_speed_ports & (1 << urbp->port)))
600		cmd |= PREAMBLE_EN;
601
602	switch (usb_pipetype(td->pipe)) {
603	case PIPE_ISOCHRONOUS:
604		tt = TT_ISOCHRONOUS;
605		cmd |= ISO_EN;
606		break;
607	case PIPE_CONTROL:
608		tt = TT_CONTROL;
609		break;
610	case PIPE_BULK:
611		tt = TT_BULK;
612		break;
613	case PIPE_INTERRUPT:
614		tt = TT_INTERRUPT;
615		break;
616	}
617
618	if (toggle)
619		cmd |= SEQ_SEL;
620
621	cmd |= ARM_EN;
622
623	/* SW part */
624	td->td_addr = c67x00->next_td_addr;
625	c67x00->next_td_addr = c67x00->next_td_addr + CY_TD_SIZE;
626
627	/* HW part */
628	td->ly_base_addr = __cpu_to_le16(c67x00->next_buf_addr);
629	td->port_length = __cpu_to_le16((c67x00->sie->sie_num << 15) |
630					(urbp->port << 14) | (len & 0x3FF));
631	td->pid_ep = ((pid & 0xF) << TD_PIDEP_OFFSET) |
632	    (usb_pipeendpoint(td->pipe) & 0xF);
633	td->dev_addr = usb_pipedevice(td->pipe) & 0x7F;
634	td->ctrl_reg = cmd;
635	td->status = 0;
636	td->retry_cnt = (tt << TT_OFFSET) | (active_flag << 4) | retry_cnt;
637	td->residue = 0;
638	td->next_td_addr = __cpu_to_le16(c67x00->next_td_addr);
639
640	/* SW part */
641	td->data = data;
642	td->urb = urb;
643	td->privdata = privdata;
644
645	c67x00->next_buf_addr += (len + 1) & ~0x01;	/* properly align */
646
647	list_add_tail(&td->td_list, &c67x00->td_list);
648	return 0;
649}
650
651static inline void c67x00_release_td(struct c67x00_td *td)
652{
653	list_del_init(&td->td_list);
654	kfree(td);
655}
656
657/* -------------------------------------------------------------------------- */
658
659static int c67x00_add_data_urb(struct c67x00_hcd *c67x00, struct urb *urb)
660{
661	int remaining;
662	int toggle;
663	int pid;
664	int ret = 0;
665	int maxps;
666	int need_empty;
667
668	toggle = usb_gettoggle(urb->dev, usb_pipeendpoint(urb->pipe),
669			       usb_pipeout(urb->pipe));
670	remaining = urb->transfer_buffer_length - urb->actual_length;
671
672	maxps = usb_maxpacket(urb->dev, urb->pipe, usb_pipeout(urb->pipe));
673
674	need_empty = (urb->transfer_flags & URB_ZERO_PACKET) &&
675	    usb_pipeout(urb->pipe) && !(remaining % maxps);
676
677	while (remaining || need_empty) {
678		int len;
679		char *td_buf;
680
681		len = (remaining > maxps) ? maxps : remaining;
682		if (!len)
683			need_empty = 0;
684
685		pid = usb_pipeout(urb->pipe) ? USB_PID_OUT : USB_PID_IN;
686		td_buf = urb->transfer_buffer + urb->transfer_buffer_length -
687		    remaining;
688		ret = c67x00_create_td(c67x00, urb, td_buf, len, pid, toggle,
689				       DATA_STAGE);
690		if (ret)
691			return ret;	/* td wasn't created */
692
693		toggle ^= 1;
694		remaining -= len;
695		if (usb_pipecontrol(urb->pipe))
696			break;
697	}
698
699	return 0;
700}
701
702/**
703 * return 0 in case more bandwidth is available, else errorcode
704 */
705static int c67x00_add_ctrl_urb(struct c67x00_hcd *c67x00, struct urb *urb)
706{
707	int ret;
708	int pid;
709
710	switch (urb->interval) {
711	default:
712	case SETUP_STAGE:
713		ret = c67x00_create_td(c67x00, urb, urb->setup_packet,
714				       8, USB_PID_SETUP, 0, SETUP_STAGE);
715		if (ret)
716			return ret;
717		urb->interval = SETUP_STAGE;
718		usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe),
719			      usb_pipeout(urb->pipe), 1);
720		break;
721	case DATA_STAGE:
722		if (urb->transfer_buffer_length) {
723			ret = c67x00_add_data_urb(c67x00, urb);
724			if (ret)
725				return ret;
726			break;
727		}		/* else fallthrough */
728	case STATUS_STAGE:
729		pid = !usb_pipeout(urb->pipe) ? USB_PID_OUT : USB_PID_IN;
730		ret = c67x00_create_td(c67x00, urb, NULL, 0, pid, 1,
731				       STATUS_STAGE);
732		if (ret)
733			return ret;
734		break;
735	}
736
737	return 0;
738}
739
740/*
741 * return 0 in case more bandwidth is available, else errorcode
742 */
743static int c67x00_add_int_urb(struct c67x00_hcd *c67x00, struct urb *urb)
744{
745	struct c67x00_urb_priv *urbp = urb->hcpriv;
746
747	if (frame_after_eq(c67x00->current_frame, urbp->ep_data->next_frame)) {
748		urbp->ep_data->next_frame =
749		    frame_add(urbp->ep_data->next_frame, urb->interval);
750		return c67x00_add_data_urb(c67x00, urb);
751	}
752	return 0;
753}
754
755static int c67x00_add_iso_urb(struct c67x00_hcd *c67x00, struct urb *urb)
756{
757	struct c67x00_urb_priv *urbp = urb->hcpriv;
758
759	if (frame_after_eq(c67x00->current_frame, urbp->ep_data->next_frame)) {
760		char *td_buf;
761		int len, pid, ret;
762
763		BUG_ON(urbp->cnt >= urb->number_of_packets);
764
765		td_buf = urb->transfer_buffer +
766		    urb->iso_frame_desc[urbp->cnt].offset;
767		len = urb->iso_frame_desc[urbp->cnt].length;
768		pid = usb_pipeout(urb->pipe) ? USB_PID_OUT : USB_PID_IN;
769
770		ret = c67x00_create_td(c67x00, urb, td_buf, len, pid, 0,
771				       urbp->cnt);
772		if (ret) {
773			dev_dbg(c67x00_hcd_dev(c67x00), "create failed: %d\n",
774				ret);
775			urb->iso_frame_desc[urbp->cnt].actual_length = 0;
776			urb->iso_frame_desc[urbp->cnt].status = ret;
777			if (urbp->cnt + 1 == urb->number_of_packets)
778				c67x00_giveback_urb(c67x00, urb, 0);
779		}
780
781		urbp->ep_data->next_frame =
782		    frame_add(urbp->ep_data->next_frame, urb->interval);
783		urbp->cnt++;
784	}
785	return 0;
786}
787
788/* -------------------------------------------------------------------------- */
789
790static void c67x00_fill_from_list(struct c67x00_hcd *c67x00, int type,
791				  int (*add)(struct c67x00_hcd *, struct urb *))
792{
793	struct c67x00_ep_data *ep_data;
794	struct urb *urb;
795
796	/* traverse every endpoint on the list */
797	list_for_each_entry(ep_data, &c67x00->list[type], node) {
798		if (!list_empty(&ep_data->queue)) {
799			/* and add the first urb */
800			/* isochronous transfer rely on this */
801			urb = list_entry(ep_data->queue.next,
802					 struct c67x00_urb_priv,
803					 hep_node)->urb;
804			add(c67x00, urb);
805		}
806	}
807}
808
809static void c67x00_fill_frame(struct c67x00_hcd *c67x00)
810{
811	struct c67x00_td *td, *ttd;
812
813	/* Check if we can proceed */
814	if (!list_empty(&c67x00->td_list)) {
815		dev_warn(c67x00_hcd_dev(c67x00),
816			 "TD list not empty! This should not happen!\n");
817		list_for_each_entry_safe(td, ttd, &c67x00->td_list, td_list) {
818			dbg_td(c67x00, td, "Unprocessed td");
819			c67x00_release_td(td);
820		}
821	}
822
823	/* Reinitialize variables */
824	c67x00->bandwidth_allocated = 0;
825	c67x00->periodic_bw_allocated = 0;
826
827	c67x00->next_td_addr = c67x00->td_base_addr;
828	c67x00->next_buf_addr = c67x00->buf_base_addr;
829
830	/* Fill the list */
831	c67x00_fill_from_list(c67x00, PIPE_ISOCHRONOUS, c67x00_add_iso_urb);
832	c67x00_fill_from_list(c67x00, PIPE_INTERRUPT, c67x00_add_int_urb);
833	c67x00_fill_from_list(c67x00, PIPE_CONTROL, c67x00_add_ctrl_urb);
834	c67x00_fill_from_list(c67x00, PIPE_BULK, c67x00_add_data_urb);
835}
836
837/* -------------------------------------------------------------------------- */
838
839/**
840 * Get TD from C67X00
841 */
842static inline void
843c67x00_parse_td(struct c67x00_hcd *c67x00, struct c67x00_td *td)
844{
845	c67x00_ll_read_mem_le16(c67x00->sie->dev,
846				td->td_addr, td, CY_TD_SIZE);
847
848	if (usb_pipein(td->pipe) && td_actual_bytes(td))
849		c67x00_ll_read_mem_le16(c67x00->sie->dev, td_ly_base_addr(td),
850					td->data, td_actual_bytes(td));
851}
852
853static int c67x00_td_to_error(struct c67x00_hcd *c67x00, struct c67x00_td *td)
854{
855	if (td->status & TD_STATUSMASK_ERR) {
856		dbg_td(c67x00, td, "ERROR_FLAG");
857		return -EILSEQ;
858	}
859	if (td->status & TD_STATUSMASK_STALL) {
860		/* dbg_td(c67x00, td, "STALL"); */
861		return -EPIPE;
862	}
863	if (td->status & TD_STATUSMASK_TMOUT) {
864		dbg_td(c67x00, td, "TIMEOUT");
865		return -ETIMEDOUT;
866	}
867
868	return 0;
869}
870
871static inline int c67x00_end_of_data(struct c67x00_td *td)
872{
873	int maxps, need_empty, remaining;
874	struct urb *urb = td->urb;
875	int act_bytes;
876
877	act_bytes = td_actual_bytes(td);
878
879	if (unlikely(!act_bytes))
880		return 1;	/* This was an empty packet */
881
882	maxps = usb_maxpacket(td_udev(td), td->pipe, usb_pipeout(td->pipe));
883
884	if (unlikely(act_bytes < maxps))
885		return 1;	/* Smaller then full packet */
886
887	remaining = urb->transfer_buffer_length - urb->actual_length;
888	need_empty = (urb->transfer_flags & URB_ZERO_PACKET) &&
889	    usb_pipeout(urb->pipe) && !(remaining % maxps);
890
891	if (unlikely(!remaining && !need_empty))
892		return 1;
893
894	return 0;
895}
896
897/* -------------------------------------------------------------------------- */
898
899/* Remove all td's from the list which come
900 * after last_td and are meant for the same pipe.
901 * This is used when a short packet has occurred */
902static inline void c67x00_clear_pipe(struct c67x00_hcd *c67x00,
903				     struct c67x00_td *last_td)
904{
905	struct c67x00_td *td, *tmp;
906	td = last_td;
907	tmp = last_td;
908	while (td->td_list.next != &c67x00->td_list) {
909		td = list_entry(td->td_list.next, struct c67x00_td, td_list);
910		if (td->pipe == last_td->pipe) {
911			c67x00_release_td(td);
912			td = tmp;
913		}
914		tmp = td;
915	}
916}
917
918/* -------------------------------------------------------------------------- */
919
920static void c67x00_handle_successful_td(struct c67x00_hcd *c67x00,
921					struct c67x00_td *td)
922{
923	struct urb *urb = td->urb;
924
925	if (!urb)
926		return;
927
928	urb->actual_length += td_actual_bytes(td);
929
930	switch (usb_pipetype(td->pipe)) {
931		/* isochronous tds are handled separately */
932	case PIPE_CONTROL:
933		switch (td->privdata) {
934		case SETUP_STAGE:
935			urb->interval =
936			    urb->transfer_buffer_length ?
937			    DATA_STAGE : STATUS_STAGE;
938			/* Don't count setup_packet with normal data: */
939			urb->actual_length = 0;
940			break;
941
942		case DATA_STAGE:
943			if (c67x00_end_of_data(td)) {
944				urb->interval = STATUS_STAGE;
945				c67x00_clear_pipe(c67x00, td);
946			}
947			break;
948
949		case STATUS_STAGE:
950			urb->interval = 0;
951			c67x00_giveback_urb(c67x00, urb, 0);
952			break;
953		}
954		break;
955
956	case PIPE_INTERRUPT:
957	case PIPE_BULK:
958		if (unlikely(c67x00_end_of_data(td))) {
959			c67x00_clear_pipe(c67x00, td);
960			c67x00_giveback_urb(c67x00, urb, 0);
961		}
962		break;
963	}
964}
965
966static void c67x00_handle_isoc(struct c67x00_hcd *c67x00, struct c67x00_td *td)
967{
968	struct urb *urb = td->urb;
969	struct c67x00_urb_priv *urbp;
970	int cnt;
971
972	if (!urb)
973		return;
974
975	urbp = urb->hcpriv;
976	cnt = td->privdata;
977
978	if (td->status & TD_ERROR_MASK)
979		urb->error_count++;
980
981	urb->iso_frame_desc[cnt].actual_length = td_actual_bytes(td);
982	urb->iso_frame_desc[cnt].status = c67x00_td_to_error(c67x00, td);
983	if (cnt + 1 == urb->number_of_packets)	/* Last packet */
984		c67x00_giveback_urb(c67x00, urb, 0);
985}
986
987/* -------------------------------------------------------------------------- */
988
989/**
990 * c67x00_check_td_list - handle tds which have been processed by the c67x00
991 * pre: current_td == 0
992 */
993static inline void c67x00_check_td_list(struct c67x00_hcd *c67x00)
994{
995	struct c67x00_td *td, *tmp;
996	struct urb *urb;
997	int ack_ok;
998	int clear_endpoint;
999
1000	list_for_each_entry_safe(td, tmp, &c67x00->td_list, td_list) {
1001		/* get the TD */
1002		c67x00_parse_td(c67x00, td);
1003		urb = td->urb;	/* urb can be NULL! */
1004		ack_ok = 0;
1005		clear_endpoint = 1;
1006
1007		/* Handle isochronous transfers separately */
1008		if (usb_pipeisoc(td->pipe)) {
1009			clear_endpoint = 0;
1010			c67x00_handle_isoc(c67x00, td);
1011			goto cont;
1012		}
1013
1014		/* When an error occurs, all td's for that pipe go into an
1015		 * inactive state. This state matches successful transfers so
1016		 * we must make sure not to service them. */
1017		if (td->status & TD_ERROR_MASK) {
1018			c67x00_giveback_urb(c67x00, urb,
1019					    c67x00_td_to_error(c67x00, td));
1020			goto cont;
1021		}
1022
1023		if ((td->status & TD_STATUSMASK_NAK) || !td_sequence_ok(td) ||
1024		    !td_acked(td))
1025			goto cont;
1026
1027		/* Sequence ok and acked, don't need to fix toggle */
1028		ack_ok = 1;
1029
1030		if (unlikely(td->status & TD_STATUSMASK_OVF)) {
1031			if (td_residue(td) & TD_RESIDUE_OVERFLOW) {
1032				/* Overflow */
1033				c67x00_giveback_urb(c67x00, urb, -EOVERFLOW);
1034				goto cont;
1035			}
1036		}
1037
1038		clear_endpoint = 0;
1039		c67x00_handle_successful_td(c67x00, td);
1040
1041cont:
1042		if (clear_endpoint)
1043			c67x00_clear_pipe(c67x00, td);
1044		if (ack_ok)
1045			usb_settoggle(td_udev(td), usb_pipeendpoint(td->pipe),
1046				      usb_pipeout(td->pipe),
1047				      !(td->ctrl_reg & SEQ_SEL));
1048		/* next in list could have been removed, due to clear_pipe! */
1049		tmp = list_entry(td->td_list.next, typeof(*td), td_list);
1050		c67x00_release_td(td);
1051	}
1052}
1053
1054/* -------------------------------------------------------------------------- */
1055
1056static inline int c67x00_all_tds_processed(struct c67x00_hcd *c67x00)
1057{
1058	/* If all tds are processed, we can check the previous frame (if
1059	 * there was any) and start our next frame.
1060	 */
1061	return !c67x00_ll_husb_get_current_td(c67x00->sie);
1062}
1063
1064/**
1065 * Send td to C67X00
1066 */
1067static void c67x00_send_td(struct c67x00_hcd *c67x00, struct c67x00_td *td)
1068{
1069	int len = td_length(td);
1070
1071	if (len && ((td->pid_ep & TD_PIDEPMASK_PID) != TD_PID_IN))
1072		c67x00_ll_write_mem_le16(c67x00->sie->dev, td_ly_base_addr(td),
1073					 td->data, len);
1074
1075	c67x00_ll_write_mem_le16(c67x00->sie->dev,
1076				 td->td_addr, td, CY_TD_SIZE);
1077}
1078
1079static void c67x00_send_frame(struct c67x00_hcd *c67x00)
1080{
1081	struct c67x00_td *td;
1082
1083	if (list_empty(&c67x00->td_list))
1084		dev_warn(c67x00_hcd_dev(c67x00),
1085			 "%s: td list should not be empty here!\n",
1086			 __func__);
1087
1088	list_for_each_entry(td, &c67x00->td_list, td_list) {
1089		if (td->td_list.next == &c67x00->td_list)
1090			td->next_td_addr = 0;	/* Last td in list */
1091
1092		c67x00_send_td(c67x00, td);
1093	}
1094
1095	c67x00_ll_husb_set_current_td(c67x00->sie, c67x00->td_base_addr);
1096}
1097
1098/* -------------------------------------------------------------------------- */
1099
1100/**
1101 * c67x00_do_work - Schedulers state machine
1102 */
1103static void c67x00_do_work(struct c67x00_hcd *c67x00)
1104{
1105	spin_lock(&c67x00->lock);
1106	/* Make sure all tds are processed */
1107	if (!c67x00_all_tds_processed(c67x00))
1108		goto out;
1109
1110	c67x00_check_td_list(c67x00);
1111
1112	/* no td's are being processed (current == 0)
1113	 * and all have been "checked" */
1114	complete(&c67x00->endpoint_disable);
1115
1116	if (!list_empty(&c67x00->td_list))
1117		goto out;
1118
1119	c67x00->current_frame = c67x00_get_current_frame_number(c67x00);
1120	if (c67x00->current_frame == c67x00->last_frame)
1121		goto out;	/* Don't send tds in same frame */
1122	c67x00->last_frame = c67x00->current_frame;
1123
1124	/* If no urbs are scheduled, our work is done */
1125	if (!c67x00->urb_count) {
1126		c67x00_ll_hpi_disable_sofeop(c67x00->sie);
1127		goto out;
1128	}
1129
1130	c67x00_fill_frame(c67x00);
1131	if (!list_empty(&c67x00->td_list))
1132		/* TD's have been added to the frame */
1133		c67x00_send_frame(c67x00);
1134
1135 out:
1136	spin_unlock(&c67x00->lock);
1137}
1138
1139/* -------------------------------------------------------------------------- */
1140
1141static void c67x00_sched_tasklet(unsigned long __c67x00)
1142{
1143	struct c67x00_hcd *c67x00 = (struct c67x00_hcd *)__c67x00;
1144	c67x00_do_work(c67x00);
1145}
1146
1147void c67x00_sched_kick(struct c67x00_hcd *c67x00)
1148{
1149	tasklet_hi_schedule(&c67x00->tasklet);
1150}
1151
1152int c67x00_sched_start_scheduler(struct c67x00_hcd *c67x00)
1153{
1154	tasklet_init(&c67x00->tasklet, c67x00_sched_tasklet,
1155		     (unsigned long)c67x00);
1156	return 0;
1157}
1158
1159void c67x00_sched_stop_scheduler(struct c67x00_hcd *c67x00)
1160{
1161	tasklet_kill(&c67x00->tasklet);
1162}
1163