linux/drivers/usb/c67x00/c67x00-sched.c
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   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, usb_pipeout(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, usb_pipeout(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}
1149