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(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(&urbp->hep_node);
 225	kfree(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(c67x00->current_frame, ep_data->next_frame))
 243			ep_data->next_frame =
 244			    frame_add(c67x00->current_frame, 1);
 245		return hep->hcpriv;
 246	}
 247
 248	/* Allocate and initialize a new c67x00 endpoint data structure */
 249	ep_data = kzalloc(sizeof(*ep_data), GFP_ATOMIC);
 250	if (!ep_data)
 251		return NULL;
 252
 253	INIT_LIST_HEAD(&ep_data->queue);
 254	INIT_LIST_HEAD(&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(urb->dev);
 260	hep->hcpriv = ep_data;
 261
 262	/* For ISOC and INT endpoints, start ASAP: */
 263	ep_data->next_frame = frame_add(c67x00->current_frame, 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(&ep_data->node)) {
 269		list_add(&ep_data->node, &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(&ep_data->node, 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(&ep_data->queue))
 293		return -EBUSY;
 294
 295	usb_put_dev(ep_data->dev);
 296	list_del(&ep_data->queue);
 297	list_del(&ep_data->node);
 298
 299	kfree(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(&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(ep)) {
 317		/* Drop the lock so we can sleep waiting for the hardware */
 318		spin_unlock_irqrestore(&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(&c67x00->endpoint_disable);
 324		c67x00_sched_kick(c67x00);
 325		wait_for_completion_timeout(&c67x00->endpoint_disable, 1 * HZ);
 326
 327		spin_lock_irqsave(&c67x00->lock, flags);
 328	}
 329
 330	spin_unlock_irqrestore(&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(urb->dev)-1;
 350
 351	/* Allocate and initialize urb private data */
 352	urbp = kzalloc(sizeof(*urbp), 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(&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(&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(last_urb->start_frame,
 412				      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(&urbp->hep_node, &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(c67x00->sie);
 425
 426	c67x00_sched_kick(c67x00);
 427	spin_unlock_irqrestore(&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(&c67x00->lock, flags);
 435	kfree(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(&c67x00->lock);
 456	usb_hcd_giveback_urb(hcd, urb, status);
 457	spin_lock(&c67x00->lock);
 458
 459	spin_unlock_irqrestore(&c67x00->lock, flags);
 460
 461	return 0;
 462
 463 done:
 464	spin_unlock_irqrestore(&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(&urbp->hep_node);
 485
 486	c67x00_release_urb(c67x00, urb);
 487	usb_hcd_unlink_urb_from_ep(c67x00_hcd_to_hcd(c67x00), urb);
 488	spin_unlock(&c67x00->lock);
 489	usb_hcd_giveback_urb(c67x00_hcd_to_hcd(c67x00), urb, status);
 490	spin_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(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(&td->td_list, &c67x00->td_list);
 634	return 0;
 635}
 636
 637static inline void c67x00_release_td(struct c67x00_td *td)
 638{
 639	list_del_init(&td->td_list);
 640	kfree(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(urb->dev, 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, 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, urb->setup_packet,
 700				       8, USB_PID_SETUP, 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, 0, pid, 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(c67x00->current_frame, urbp->ep_data->next_frame)) {
 735		urbp->ep_data->next_frame =
 736		    frame_add(urbp->ep_data->next_frame, 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(c67x00->current_frame, 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, td_buf, len, pid, 0,
 758				       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, 0);
 766		}
 767
 768		urbp->ep_data->next_frame =
 769		    frame_add(urbp->ep_data->next_frame, 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(&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(&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, "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, c67x00_add_iso_urb);
 819	c67x00_fill_from_list(c67x00, PIPE_INTERRUPT, c67x00_add_int_urb);
 820	c67x00_fill_from_list(c67x00, PIPE_CONTROL, c67x00_add_ctrl_urb);
 821	c67x00_fill_from_list(c67x00, PIPE_BULK, 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(c67x00->sie->dev,
 833				td->td_addr, td, CY_TD_SIZE);
 834
 835	if (usb_pipein(td->pipe) && td_actual_bytes(td))
 836		c67x00_ll_read_mem_le16(c67x00->sie->dev, td_ly_base_addr(td),
 837					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, "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, "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), 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, td);
 933			}
 934			break;
 935
 936		case STATUS_STAGE:
 937			urb->interval = 0;
 938			c67x00_giveback_urb(c67x00, urb, 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, td);
 947			c67x00_giveback_urb(c67x00, urb, 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, 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					    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, -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, 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(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(c67x00->sie->dev, td_ly_base_addr(td),
1058					 td->data, len);
1059
1060	c67x00_ll_write_mem_le16(c67x00->sie->dev,
1061				 td->td_addr, 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(&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(c67x00->sie, 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(&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(&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(c67x00->sie);
1112		goto out;
1113	}
1114
1115	c67x00_fill_frame(c67x00);
1116	if (!list_empty(&c67x00->td_list))
1117		/* TD's have been added to the frame */
1118		c67x00_send_frame(c67x00);
1119
1120 out:
1121	spin_unlock(&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(system_highpri_wq, &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(&c67x00->work);
1148}