drivers/usb/gadget/udc/aspeed-vhub/epn.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * aspeed-vhub -- Driver for Aspeed SoC "vHub" USB gadget
   4  *
   5  * epn.c - Generic endpoints management
   6  *
   7  * Copyright 2017 IBM Corporation
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/delay.h>
  19 #include <linux/ioport.h>
  20 #include <linux/slab.h>
  21 #include <linux/errno.h>
  22 #include <linux/list.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/proc_fs.h>
  25 #include <linux/prefetch.h>
  26 #include <linux/clk.h>
  27 #include <linux/usb/gadget.h>
  28 #include <linux/of.h>
  29 #include <linux/of_gpio.h>
  30 #include <linux/regmap.h>
  31 #include <linux/dma-mapping.h>
  32
  33 #include "vhub.h"
  34
  35 #define EXTRA_CHECKS
  36
  37 #ifdef EXTRA_CHECKS
  38 #define CHECK(ep, expr, fmt...)                                 \
  39         do {                                                    \
  40                 if (!(expr)) EPDBG(ep, "CHECK:" fmt);           \
  41         } while(0)
  42 #else
  43 #define CHECK(ep, expr, fmt...) do { } while(0)
  44 #endif
  45
  46 static void ast_vhub_epn_kick(struct ast_vhub_ep *ep, struct ast_vhub_req *req)
  47 {
  48         unsigned int act = req->req.actual;
  49         unsigned int len = req->req.length;
  50         unsigned int chunk;
  51
  52         /* There should be no DMA ongoing */
  53         WARN_ON(req->active);
  54
  55         /* Calculate next chunk size */
  56         chunk = len - act;
  57         if (chunk > ep->ep.maxpacket)
  58                 chunk = ep->ep.maxpacket;
  59         else if ((chunk < ep->ep.maxpacket) || !req->req.zero)
  60                 req->last_desc = 1;
  61
  62         EPVDBG(ep, "kick req %p act=%d/%d chunk=%d last=%d\n",
  63                req, act, len, chunk, req->last_desc);
  64
  65         /* If DMA unavailable, using staging EP buffer */
  66         if (!req->req.dma) {
  67
  68                 /* For IN transfers, copy data over first */
  69                 if (ep->epn.is_in) {
  70                         memcpy(ep->buf, req->req.buf + act, chunk);
  71                         vhub_dma_workaround(ep->buf);
  72                 }
  73                 writel(ep->buf_dma, ep->epn.regs + AST_VHUB_EP_DESC_BASE);
  74         } else {
  75                 if (ep->epn.is_in)
  76                         vhub_dma_workaround(req->req.buf);
  77                 writel(req->req.dma + act, ep->epn.regs + AST_VHUB_EP_DESC_BASE);
  78         }
  79
  80         /* Start DMA */
  81         req->active = true;
  82         writel(VHUB_EP_DMA_SET_TX_SIZE(chunk),
  83                ep->epn.regs + AST_VHUB_EP_DESC_STATUS);
  84         writel(VHUB_EP_DMA_SET_TX_SIZE(chunk) | VHUB_EP_DMA_SINGLE_KICK,
  85                ep->epn.regs + AST_VHUB_EP_DESC_STATUS);
  86 }
  87
  88 static void ast_vhub_epn_handle_ack(struct ast_vhub_ep *ep)
  89 {
  90         struct ast_vhub_req *req;
  91         unsigned int len;
  92         u32 stat;
  93
  94         /* Read EP status */
  95         stat = readl(ep->epn.regs + AST_VHUB_EP_DESC_STATUS);
  96
  97         /* Grab current request if any */
  98         req = list_first_entry_or_null(&ep->queue, struct ast_vhub_req, queue);
  99
 100         EPVDBG(ep, "ACK status=%08x is_in=%d, req=%p (active=%d)\n",
 101                stat, ep->epn.is_in, req, req ? req->active : 0);
 102
 103         /* In absence of a request, bail out, must have been dequeued */
 104         if (!req)
 105                 return;
 106
 107         /*
 108          * Request not active, move on to processing queue, active request
 109          * was probably dequeued
 110          */
 111         if (!req->active)
 112                 goto next_chunk;
 113
 114         /* Check if HW has moved on */
 115         if (VHUB_EP_DMA_RPTR(stat) != 0) {
 116                 EPDBG(ep, "DMA read pointer not 0 !\n");
 117                 return;
 118         }
 119
 120         /* No current DMA ongoing */
 121         req->active = false;
 122
 123         /* Grab lenght out of HW */
 124         len = VHUB_EP_DMA_TX_SIZE(stat);
 125
 126         /* If not using DMA, copy data out if needed */
 127         if (!req->req.dma && !ep->epn.is_in && len)
 128                 memcpy(req->req.buf + req->req.actual, ep->buf, len);
 129
 130         /* Adjust size */
 131         req->req.actual += len;
 132
 133         /* Check for short packet */
 134         if (len < ep->ep.maxpacket)
 135                 req->last_desc = 1;
 136
 137         /* That's it ? complete the request and pick a new one */
 138         if (req->last_desc >= 0) {
 139                 ast_vhub_done(ep, req, 0);
 140                 req = list_first_entry_or_null(&ep->queue, struct ast_vhub_req,
 141                                                queue);
 142
 143                 /*
 144                  * Due to lock dropping inside "done" the next request could
 145                  * already be active, so check for that and bail if needed.
 146                  */
 147                 if (!req || req->active)
 148                         return;
 149         }
 150
 151  next_chunk:
 152         ast_vhub_epn_kick(ep, req);
 153 }
 154
 155 static inline unsigned int ast_vhub_count_free_descs(struct ast_vhub_ep *ep)
 156 {
 157         /*
 158          * d_next == d_last means descriptor list empty to HW,
 159          * thus we can only have AST_VHUB_DESCS_COUNT-1 descriptors
 160          * in the list
 161          */
 162         return (ep->epn.d_last + AST_VHUB_DESCS_COUNT - ep->epn.d_next - 1) &
 163                 (AST_VHUB_DESCS_COUNT - 1);
 164 }
 165
 166 static void ast_vhub_epn_kick_desc(struct ast_vhub_ep *ep,
 167                                    struct ast_vhub_req *req)
 168 {
 169         struct ast_vhub_desc *desc = NULL;
 170         unsigned int act = req->act_count;
 171         unsigned int len = req->req.length;
 172         unsigned int chunk;
 173
 174         /* Mark request active if not already */
 175         req->active = true;
 176
 177         /* If the request was already completely written, do nothing */
 178         if (req->last_desc >= 0)
 179                 return;
 180
 181         EPVDBG(ep, "kick act=%d/%d chunk_max=%d free_descs=%d\n",
 182                act, len, ep->epn.chunk_max, ast_vhub_count_free_descs(ep));
 183
 184         /* While we can create descriptors */
 185         while (ast_vhub_count_free_descs(ep) && req->last_desc < 0) {
 186                 unsigned int d_num;
 187
 188                 /* Grab next free descriptor */
 189                 d_num = ep->epn.d_next;
 190                 desc = &ep->epn.descs[d_num];
 191                 ep->epn.d_next = (d_num + 1) & (AST_VHUB_DESCS_COUNT - 1);
 192
 193                 /* Calculate next chunk size */
 194                 chunk = len - act;
 195                 if (chunk <= ep->epn.chunk_max) {
 196                         /*
 197                          * Is this the last packet ? Because of having up to 8
 198                          * packets in a descriptor we can't just compare "chunk"
 199                          * with ep.maxpacket. We have to see if it's a multiple
 200                          * of it to know if we have to send a zero packet.
 201                          * Sadly that involves a modulo which is a bit expensive
 202                          * but probably still better than not doing it.
 203                          */
 204                         if (!chunk || !req->req.zero || (chunk % ep->ep.maxpacket) != 0)
 205                                 req->last_desc = d_num;
 206                 } else {
 207                         chunk = ep->epn.chunk_max;
 208                 }
 209
 210                 EPVDBG(ep, " chunk: act=%d/%d chunk=%d last=%d desc=%d free=%d\n",
 211                        act, len, chunk, req->last_desc, d_num,
 212                        ast_vhub_count_free_descs(ep));
 213
 214                 /* Populate descriptor */
 215                 desc->w0 = cpu_to_le32(req->req.dma + act);
 216
 217                 /* Interrupt if end of request or no more descriptors */
 218
 219                 /*
 220                  * TODO: Be smarter about it, if we don't have enough
 221                  * descriptors request an interrupt before queue empty
 222                  * or so in order to be able to populate more before
 223                  * the HW runs out. This isn't a problem at the moment
 224                  * as we use 256 descriptors and only put at most one
 225                  * request in the ring.
 226                  */
 227                 desc->w1 = cpu_to_le32(VHUB_DSC1_IN_SET_LEN(chunk));
 228                 if (req->last_desc >= 0 || !ast_vhub_count_free_descs(ep))
 229                         desc->w1 |= cpu_to_le32(VHUB_DSC1_IN_INTERRUPT);
 230
 231                 /* Account packet */
 232                 req->act_count = act = act + chunk;
 233         }
 234
 235         if (likely(desc))
 236                 vhub_dma_workaround(desc);
 237
 238         /* Tell HW about new descriptors */
 239         writel(VHUB_EP_DMA_SET_CPU_WPTR(ep->epn.d_next),
 240                ep->epn.regs + AST_VHUB_EP_DESC_STATUS);
 241
 242         EPVDBG(ep, "HW kicked, d_next=%d dstat=%08x\n",
 243                ep->epn.d_next, readl(ep->epn.regs + AST_VHUB_EP_DESC_STATUS));
 244 }
 245
 246 static void ast_vhub_epn_handle_ack_desc(struct ast_vhub_ep *ep)
 247 {
 248         struct ast_vhub_req *req;
 249         unsigned int len, d_last;
 250         u32 stat, stat1;
 251
 252         /* Read EP status, workaround HW race */
 253         do {
 254                 stat = readl(ep->epn.regs + AST_VHUB_EP_DESC_STATUS);
 255                 stat1 = readl(ep->epn.regs + AST_VHUB_EP_DESC_STATUS);
 256         } while(stat != stat1);
 257
 258         /* Extract RPTR */
 259         d_last = VHUB_EP_DMA_RPTR(stat);
 260
 261         /* Grab current request if any */
 262         req = list_first_entry_or_null(&ep->queue, struct ast_vhub_req, queue);
 263
 264         EPVDBG(ep, "ACK status=%08x is_in=%d ep->d_last=%d..%d\n",
 265                stat, ep->epn.is_in, ep->epn.d_last, d_last);
 266
 267         /* Check all completed descriptors */
 268         while (ep->epn.d_last != d_last) {
 269                 struct ast_vhub_desc *desc;
 270                 unsigned int d_num;
 271                 bool is_last_desc;
 272
 273                 /* Grab next completed descriptor */
 274                 d_num = ep->epn.d_last;
 275                 desc = &ep->epn.descs[d_num];
 276                 ep->epn.d_last = (d_num + 1) & (AST_VHUB_DESCS_COUNT - 1);
 277
 278                 /* Grab len out of descriptor */
 279                 len = VHUB_DSC1_IN_LEN(le32_to_cpu(desc->w1));
 280
 281                 EPVDBG(ep, " desc %d len=%d req=%p (act=%d)\n",
 282                        d_num, len, req, req ? req->active : 0);
 283
 284                 /* If no active request pending, move on */
 285                 if (!req || !req->active)
 286                         continue;
 287
 288                 /* Adjust size */
 289                 req->req.actual += len;
 290
 291                 /* Is that the last chunk ? */
 292                 is_last_desc = req->last_desc == d_num;
 293                 CHECK(ep, is_last_desc == (len < ep->ep.maxpacket ||
 294                                            (req->req.actual >= req->req.length &&
 295                                             !req->req.zero)),
 296                       "Last packet discrepancy: last_desc=%d len=%d r.act=%d "
 297                       "r.len=%d r.zero=%d mp=%d\n",
 298                       is_last_desc, len, req->req.actual, req->req.length,
 299                       req->req.zero, ep->ep.maxpacket);
 300
 301                 if (is_last_desc) {
 302                         /*
 303                          * Because we can only have one request at a time
 304                          * in our descriptor list in this implementation,
 305                          * d_last and ep->d_last should now be equal
 306                          */
 307                         CHECK(ep, d_last == ep->epn.d_last,
 308                               "DMA read ptr mismatch %d vs %d\n",
 309                               d_last, ep->epn.d_last);
 310
 311                         /* Note: done will drop and re-acquire the lock */
 312                         ast_vhub_done(ep, req, 0);
 313                         req = list_first_entry_or_null(&ep->queue,
 314                                                        struct ast_vhub_req,
 315                                                        queue);
 316                         break;
 317                 }
 318         }
 319
 320         /* More work ? */
 321         if (req)
 322                 ast_vhub_epn_kick_desc(ep, req);
 323 }
 324
 325 void ast_vhub_epn_ack_irq(struct ast_vhub_ep *ep)
 326 {
 327         if (ep->epn.desc_mode)
 328                 ast_vhub_epn_handle_ack_desc(ep);
 329         else
 330                 ast_vhub_epn_handle_ack(ep);
 331 }
 332
 333 static int ast_vhub_epn_queue(struct usb_ep* u_ep, struct usb_request *u_req,
 334                               gfp_t gfp_flags)
 335 {
 336         struct ast_vhub_req *req = to_ast_req(u_req);
 337         struct ast_vhub_ep *ep = to_ast_ep(u_ep);
 338         struct ast_vhub *vhub = ep->vhub;
 339         unsigned long flags;
 340         bool empty;
 341         int rc;
 342
 343         /* Paranoid checks */
 344         if (!u_req || !u_req->complete || !u_req->buf) {
 345                 dev_warn(&vhub->pdev->dev, "Bogus EPn request ! u_req=%p\n", u_req);
 346                 if (u_req) {
 347                         dev_warn(&vhub->pdev->dev, "complete=%p internal=%d\n",
 348                                  u_req->complete, req->internal);
 349                 }
 350                 return -EINVAL;
 351         }
 352
 353         /* Endpoint enabled ? */
 354         if (!ep->epn.enabled || !u_ep->desc || !ep->dev || !ep->d_idx ||
 355             !ep->dev->enabled || ep->dev->suspended) {
 356                 EPDBG(ep,"Enqueing request on wrong or disabled EP\n");
 357                 return -ESHUTDOWN;
 358         }
 359
 360         /* Map request for DMA if possible. For now, the rule for DMA is
 361          * that:
 362          *
 363          *  * For single stage mode (no descriptors):
 364          *
 365          *   - The buffer is aligned to a 8 bytes boundary (HW requirement)
 366          *   - For a OUT endpoint, the request size is a multiple of the EP
 367          *     packet size (otherwise the controller will DMA past the end
 368          *     of the buffer if the host is sending a too long packet).
 369          *
 370          *  * For descriptor mode (tx only for now), always.
 371          *
 372          * We could relax the latter by making the decision to use the bounce
 373          * buffer based on the size of a given *segment* of the request rather
 374          * than the whole request.
 375          */
 376         if (ep->epn.desc_mode ||
 377             ((((unsigned long)u_req->buf & 7) == 0) &&
 378              (ep->epn.is_in || !(u_req->length & (u_ep->maxpacket - 1))))) {
 379                 rc = usb_gadget_map_request_by_dev(&vhub->pdev->dev, u_req,
 380                                             ep->epn.is_in);
 381                 if (rc) {
 382                         dev_warn(&vhub->pdev->dev,
 383                                  "Request mapping failure %d\n", rc);
 384                         return rc;
 385                 }
 386         } else
 387                 u_req->dma = 0;
 388
 389         EPVDBG(ep, "enqueue req @%p\n", req);
 390         EPVDBG(ep, " l=%d dma=0x%x zero=%d noshort=%d noirq=%d is_in=%d\n",
 391                u_req->length, (u32)u_req->dma, u_req->zero,
 392                u_req->short_not_ok, u_req->no_interrupt,
 393                ep->epn.is_in);
 394
 395         /* Initialize request progress fields */
 396         u_req->status = -EINPROGRESS;
 397         u_req->actual = 0;
 398         req->act_count = 0;
 399         req->active = false;
 400         req->last_desc = -1;
 401         spin_lock_irqsave(&vhub->lock, flags);
 402         empty = list_empty(&ep->queue);
 403
 404         /* Add request to list and kick processing if empty */
 405         list_add_tail(&req->queue, &ep->queue);
 406         if (empty) {
 407                 if (ep->epn.desc_mode)
 408                         ast_vhub_epn_kick_desc(ep, req);
 409                 else
 410                         ast_vhub_epn_kick(ep, req);
 411         }
 412         spin_unlock_irqrestore(&vhub->lock, flags);
 413
 414         return 0;
 415 }
 416
 417 static void ast_vhub_stop_active_req(struct ast_vhub_ep *ep,
 418                                      bool restart_ep)
 419 {
 420         u32 state, reg, loops;
 421
 422         /* Stop DMA activity */
 423         if (ep->epn.desc_mode)
 424                 writel(VHUB_EP_DMA_CTRL_RESET, ep->epn.regs + AST_VHUB_EP_DMA_CTLSTAT);
 425         else
 426                 writel(0, ep->epn.regs + AST_VHUB_EP_DMA_CTLSTAT);
 427
 428         /* Wait for it to complete */
 429         for (loops = 0; loops < 1000; loops++) {
 430                 state = readl(ep->epn.regs + AST_VHUB_EP_DMA_CTLSTAT);
 431                 state = VHUB_EP_DMA_PROC_STATUS(state);
 432                 if (state == EP_DMA_PROC_RX_IDLE ||
 433                     state == EP_DMA_PROC_TX_IDLE)
 434                         break;
 435                 udelay(1);
 436         }
 437         if (loops >= 1000)
 438                 dev_warn(&ep->vhub->pdev->dev, "Timeout waiting for DMA\n");
 439
 440         /* If we don't have to restart the endpoint, that's it */
 441         if (!restart_ep)
 442                 return;
 443
 444         /* Restart the endpoint */
 445         if (ep->epn.desc_mode) {
 446                 /*
 447                  * Take out descriptors by resetting the DMA read
 448                  * pointer to be equal to the CPU write pointer.
 449                  *
 450                  * Note: If we ever support creating descriptors for
 451                  * requests that aren't the head of the queue, we
 452                  * may have to do something more complex here,
 453                  * especially if the request being taken out is
 454                  * not the current head descriptors.
 455                  */
 456                 reg = VHUB_EP_DMA_SET_RPTR(ep->epn.d_next) |
 457                         VHUB_EP_DMA_SET_CPU_WPTR(ep->epn.d_next);
 458                 writel(reg, ep->epn.regs + AST_VHUB_EP_DESC_STATUS);
 459
 460                 /* Then turn it back on */
 461                 writel(ep->epn.dma_conf,
 462                        ep->epn.regs + AST_VHUB_EP_DMA_CTLSTAT);
 463         } else {
 464                 /* Single mode: just turn it back on */
 465                 writel(ep->epn.dma_conf,
 466                        ep->epn.regs + AST_VHUB_EP_DMA_CTLSTAT);
 467         }
 468 }
 469
 470 static int ast_vhub_epn_dequeue(struct usb_ep* u_ep, struct usb_request *u_req)
 471 {
 472         struct ast_vhub_ep *ep = to_ast_ep(u_ep);
 473         struct ast_vhub *vhub = ep->vhub;
 474         struct ast_vhub_req *req;
 475         unsigned long flags;
 476         int rc = -EINVAL;
 477
 478         spin_lock_irqsave(&vhub->lock, flags);
 479
 480         /* Make sure it's actually queued on this endpoint */
 481         list_for_each_entry (req, &ep->queue, queue) {
 482                 if (&req->req == u_req)
 483                         break;
 484         }
 485
 486         if (&req->req == u_req) {
 487                 EPVDBG(ep, "dequeue req @%p active=%d\n",
 488                        req, req->active);
 489                 if (req->active)
 490                         ast_vhub_stop_active_req(ep, true);
 491                 ast_vhub_done(ep, req, -ECONNRESET);
 492                 rc = 0;
 493         }
 494
 495         spin_unlock_irqrestore(&vhub->lock, flags);
 496         return rc;
 497 }
 498
 499 void ast_vhub_update_epn_stall(struct ast_vhub_ep *ep)
 500 {
 501         u32 reg;
 502
 503         if (WARN_ON(ep->d_idx == 0))
 504                 return;
 505         reg = readl(ep->epn.regs + AST_VHUB_EP_CONFIG);
 506         if (ep->epn.stalled || ep->epn.wedged)
 507                 reg |= VHUB_EP_CFG_STALL_CTRL;
 508         else
 509                 reg &= ~VHUB_EP_CFG_STALL_CTRL;
 510         writel(reg, ep->epn.regs + AST_VHUB_EP_CONFIG);
 511
 512         if (!ep->epn.stalled && !ep->epn.wedged)
 513                 writel(VHUB_EP_TOGGLE_SET_EPNUM(ep->epn.g_idx),
 514                        ep->vhub->regs + AST_VHUB_EP_TOGGLE);
 515 }
 516
 517 static int ast_vhub_set_halt_and_wedge(struct usb_ep* u_ep, bool halt,
 518                                       bool wedge)
 519 {
 520         struct ast_vhub_ep *ep = to_ast_ep(u_ep);
 521         struct ast_vhub *vhub = ep->vhub;
 522         unsigned long flags;
 523
 524         EPDBG(ep, "Set halt (%d) & wedge (%d)\n", halt, wedge);
 525
 526         if (!u_ep || !u_ep->desc)
 527                 return -EINVAL;
 528         if (ep->d_idx == 0)
 529                 return 0;
 530         if (ep->epn.is_iso)
 531                 return -EOPNOTSUPP;
 532
 533         spin_lock_irqsave(&vhub->lock, flags);
 534
 535         /* Fail with still-busy IN endpoints */
 536         if (halt && ep->epn.is_in && !list_empty(&ep->queue)) {
 537                 spin_unlock_irqrestore(&vhub->lock, flags);
 538                 return -EAGAIN;
 539         }
 540         ep->epn.stalled = halt;
 541         ep->epn.wedged = wedge;
 542         ast_vhub_update_epn_stall(ep);
 543
 544         spin_unlock_irqrestore(&vhub->lock, flags);
 545
 546         return 0;
 547 }
 548
 549 static int ast_vhub_epn_set_halt(struct usb_ep *u_ep, int value)
 550 {
 551         return ast_vhub_set_halt_and_wedge(u_ep, value != 0, false);
 552 }
 553
 554 static int ast_vhub_epn_set_wedge(struct usb_ep *u_ep)
 555 {
 556         return ast_vhub_set_halt_and_wedge(u_ep, true, true);
 557 }
 558
 559 static int ast_vhub_epn_disable(struct usb_ep* u_ep)
 560 {
 561         struct ast_vhub_ep *ep = to_ast_ep(u_ep);
 562         struct ast_vhub *vhub = ep->vhub;
 563         unsigned long flags;
 564         u32 imask, ep_ier;
 565
 566         EPDBG(ep, "Disabling !\n");
 567
 568         spin_lock_irqsave(&vhub->lock, flags);
 569
 570         ep->epn.enabled = false;
 571
 572         /* Stop active DMA if any */
 573         ast_vhub_stop_active_req(ep, false);
 574
 575         /* Disable endpoint */
 576         writel(0, ep->epn.regs + AST_VHUB_EP_CONFIG);
 577
 578         /* Disable ACK interrupt */
 579         imask = VHUB_EP_IRQ(ep->epn.g_idx);
 580         ep_ier = readl(vhub->regs + AST_VHUB_EP_ACK_IER);
 581         ep_ier &= ~imask;
 582         writel(ep_ier, vhub->regs + AST_VHUB_EP_ACK_IER);
 583         writel(imask, vhub->regs + AST_VHUB_EP_ACK_ISR);
 584
 585         /* Nuke all pending requests */
 586         ast_vhub_nuke(ep, -ESHUTDOWN);
 587
 588         /* No more descriptor associated with request */
 589         ep->ep.desc = NULL;
 590
 591         spin_unlock_irqrestore(&vhub->lock, flags);
 592
 593         return 0;
 594 }
 595
 596 static int ast_vhub_epn_enable(struct usb_ep* u_ep,
 597                                const struct usb_endpoint_descriptor *desc)
 598 {
 599         static const char *ep_type_string[] __maybe_unused = { "ctrl",
 600                                                                "isoc",
 601                                                                "bulk",
 602                                                                "intr" };
 603         struct ast_vhub_ep *ep = to_ast_ep(u_ep);
 604         struct ast_vhub_dev *dev;
 605         struct ast_vhub *vhub;
 606         u16 maxpacket, type;
 607         unsigned long flags;
 608         u32 ep_conf, ep_ier, imask;
 609
 610         /* Check arguments */
 611         if (!u_ep || !desc)
 612                 return -EINVAL;
 613
 614         maxpacket = usb_endpoint_maxp(desc);
 615         if (!ep->d_idx || !ep->dev ||
 616             desc->bDescriptorType != USB_DT_ENDPOINT ||
 617             maxpacket == 0 || maxpacket > ep->ep.maxpacket) {
 618                 EPDBG(ep, "Invalid EP enable,d_idx=%d,dev=%p,type=%d,mp=%d/%d\n",
 619                       ep->d_idx, ep->dev, desc->bDescriptorType,
 620                       maxpacket, ep->ep.maxpacket);
 621                 return -EINVAL;
 622         }
 623         if (ep->d_idx != usb_endpoint_num(desc)) {
 624                 EPDBG(ep, "EP number mismatch !\n");
 625                 return -EINVAL;
 626         }
 627
 628         if (ep->epn.enabled) {
 629                 EPDBG(ep, "Already enabled\n");
 630                 return -EBUSY;
 631         }
 632         dev = ep->dev;
 633         vhub = ep->vhub;
 634
 635         /* Check device state */
 636         if (!dev->driver) {
 637                 EPDBG(ep, "Bogus device state: driver=%p speed=%d\n",
 638                        dev->driver, dev->gadget.speed);
 639                 return -ESHUTDOWN;
 640         }
 641
 642         /* Grab some info from the descriptor */
 643         ep->epn.is_in = usb_endpoint_dir_in(desc);
 644         ep->ep.maxpacket = maxpacket;
 645         type = usb_endpoint_type(desc);
 646         ep->epn.d_next = ep->epn.d_last = 0;
 647         ep->epn.is_iso = false;
 648         ep->epn.stalled = false;
 649         ep->epn.wedged = false;
 650
 651         EPDBG(ep, "Enabling [%s] %s num %d maxpacket=%d\n",
 652               ep->epn.is_in ? "in" : "out", ep_type_string[type],
 653               usb_endpoint_num(desc), maxpacket);
 654
 655         /* Can we use DMA descriptor mode ? */
 656         ep->epn.desc_mode = ep->epn.descs && ep->epn.is_in;
 657         if (ep->epn.desc_mode)
 658                 memset(ep->epn.descs, 0, 8 * AST_VHUB_DESCS_COUNT);
 659
 660         /*
 661          * Large send function can send up to 8 packets from
 662          * one descriptor with a limit of 4095 bytes.
 663          */
 664         ep->epn.chunk_max = ep->ep.maxpacket;
 665         if (ep->epn.is_in) {
 666                 ep->epn.chunk_max <<= 3;
 667                 while (ep->epn.chunk_max > 4095)
 668                         ep->epn.chunk_max -= ep->ep.maxpacket;
 669         }
 670
 671         switch(type) {
 672         case USB_ENDPOINT_XFER_CONTROL:
 673                 EPDBG(ep, "Only one control endpoint\n");
 674                 return -EINVAL;
 675         case USB_ENDPOINT_XFER_INT:
 676                 ep_conf = VHUB_EP_CFG_SET_TYPE(EP_TYPE_INT);
 677                 break;
 678         case USB_ENDPOINT_XFER_BULK:
 679                 ep_conf = VHUB_EP_CFG_SET_TYPE(EP_TYPE_BULK);
 680                 break;
 681         case USB_ENDPOINT_XFER_ISOC:
 682                 ep_conf = VHUB_EP_CFG_SET_TYPE(EP_TYPE_ISO);
 683                 ep->epn.is_iso = true;
 684                 break;
 685         default:
 686                 return -EINVAL;
 687         }
 688
 689         /* Encode the rest of the EP config register */
 690         if (maxpacket < 1024)
 691                 ep_conf |= VHUB_EP_CFG_SET_MAX_PKT(maxpacket);
 692         if (!ep->epn.is_in)
 693                 ep_conf |= VHUB_EP_CFG_DIR_OUT;
 694         ep_conf |= VHUB_EP_CFG_SET_EP_NUM(usb_endpoint_num(desc));
 695         ep_conf |= VHUB_EP_CFG_ENABLE;
 696         ep_conf |= VHUB_EP_CFG_SET_DEV(dev->index + 1);
 697         EPVDBG(ep, "config=%08x\n", ep_conf);
 698
 699         spin_lock_irqsave(&vhub->lock, flags);
 700
 701         /* Disable HW and reset DMA */
 702         writel(0, ep->epn.regs + AST_VHUB_EP_CONFIG);
 703         writel(VHUB_EP_DMA_CTRL_RESET,
 704                ep->epn.regs + AST_VHUB_EP_DMA_CTLSTAT);
 705
 706         /* Configure and enable */
 707         writel(ep_conf, ep->epn.regs + AST_VHUB_EP_CONFIG);
 708
 709         if (ep->epn.desc_mode) {
 710                 /* Clear DMA status, including the DMA read ptr */
 711                 writel(0, ep->epn.regs + AST_VHUB_EP_DESC_STATUS);
 712
 713                 /* Set descriptor base */
 714                 writel(ep->epn.descs_dma,
 715                        ep->epn.regs + AST_VHUB_EP_DESC_BASE);
 716
 717                 /* Set base DMA config value */
 718                 ep->epn.dma_conf = VHUB_EP_DMA_DESC_MODE;
 719                 if (ep->epn.is_in)
 720                         ep->epn.dma_conf |= VHUB_EP_DMA_IN_LONG_MODE;
 721
 722                 /* First reset and disable all operations */
 723                 writel(ep->epn.dma_conf | VHUB_EP_DMA_CTRL_RESET,
 724                        ep->epn.regs + AST_VHUB_EP_DMA_CTLSTAT);
 725
 726                 /* Enable descriptor mode */
 727                 writel(ep->epn.dma_conf,
 728                        ep->epn.regs + AST_VHUB_EP_DMA_CTLSTAT);
 729         } else {
 730                 /* Set base DMA config value */
 731                 ep->epn.dma_conf = VHUB_EP_DMA_SINGLE_STAGE;
 732
 733                 /* Reset and switch to single stage mode */
 734                 writel(ep->epn.dma_conf | VHUB_EP_DMA_CTRL_RESET,
 735                        ep->epn.regs + AST_VHUB_EP_DMA_CTLSTAT);
 736                 writel(ep->epn.dma_conf,
 737                        ep->epn.regs + AST_VHUB_EP_DMA_CTLSTAT);
 738                 writel(0, ep->epn.regs + AST_VHUB_EP_DESC_STATUS);
 739         }
 740
 741         /* Cleanup data toggle just in case */
 742         writel(VHUB_EP_TOGGLE_SET_EPNUM(ep->epn.g_idx),
 743                vhub->regs + AST_VHUB_EP_TOGGLE);
 744
 745         /* Cleanup and enable ACK interrupt */
 746         imask = VHUB_EP_IRQ(ep->epn.g_idx);
 747         writel(imask, vhub->regs + AST_VHUB_EP_ACK_ISR);
 748         ep_ier = readl(vhub->regs + AST_VHUB_EP_ACK_IER);
 749         ep_ier |= imask;
 750         writel(ep_ier, vhub->regs + AST_VHUB_EP_ACK_IER);
 751
 752         /* Woot, we are online ! */
 753         ep->epn.enabled = true;
 754
 755         spin_unlock_irqrestore(&vhub->lock, flags);
 756
 757         return 0;
 758 }
 759
 760 static void ast_vhub_epn_dispose(struct usb_ep *u_ep)
 761 {
 762         struct ast_vhub_ep *ep = to_ast_ep(u_ep);
 763
 764         if (WARN_ON(!ep->dev || !ep->d_idx))
 765                 return;
 766
 767         EPDBG(ep, "Releasing endpoint\n");
 768
 769         /* Take it out of the EP list */
 770         list_del_init(&ep->ep.ep_list);
 771
 772         /* Mark the address free in the device */
 773         ep->dev->epns[ep->d_idx - 1] = NULL;
 774
 775         /* Free name & DMA buffers */
 776         kfree(ep->ep.name);
 777         ep->ep.name = NULL;
 778         dma_free_coherent(&ep->vhub->pdev->dev,
 779                           AST_VHUB_EPn_MAX_PACKET +
 780                           8 * AST_VHUB_DESCS_COUNT,
 781                           ep->buf, ep->buf_dma);
 782         ep->buf = NULL;
 783         ep->epn.descs = NULL;
 784
 785         /* Mark free */
 786         ep->dev = NULL;
 787 }
 788
 789 static const struct usb_ep_ops ast_vhub_epn_ops = {
 790         .enable         = ast_vhub_epn_enable,
 791         .disable        = ast_vhub_epn_disable,
 792         .dispose        = ast_vhub_epn_dispose,
 793         .queue          = ast_vhub_epn_queue,
 794         .dequeue        = ast_vhub_epn_dequeue,
 795         .set_halt       = ast_vhub_epn_set_halt,
 796         .set_wedge      = ast_vhub_epn_set_wedge,
 797         .alloc_request  = ast_vhub_alloc_request,
 798         .free_request   = ast_vhub_free_request,
 799 };
 800
 801 struct ast_vhub_ep *ast_vhub_alloc_epn(struct ast_vhub_dev *d, u8 addr)
 802 {
 803         struct ast_vhub *vhub = d->vhub;
 804         struct ast_vhub_ep *ep;
 805         unsigned long flags;
 806         int i;
 807
 808         /* Find a free one (no device) */
 809         spin_lock_irqsave(&vhub->lock, flags);
 810         for (i = 0; i < AST_VHUB_NUM_GEN_EPs; i++)
 811                 if (vhub->epns[i].dev == NULL)
 812                         break;
 813         if (i >= AST_VHUB_NUM_GEN_EPs) {
 814                 spin_unlock_irqrestore(&vhub->lock, flags);
 815                 return NULL;
 816         }
 817
 818         /* Set it up */
 819         ep = &vhub->epns[i];
 820         ep->dev = d;
 821         spin_unlock_irqrestore(&vhub->lock, flags);
 822
 823         DDBG(d, "Allocating gen EP %d for addr %d\n", i, addr);
 824         INIT_LIST_HEAD(&ep->queue);
 825         ep->d_idx = addr;
 826         ep->vhub = vhub;
 827         ep->ep.ops = &ast_vhub_epn_ops;
 828         ep->ep.name = kasprintf(GFP_KERNEL, "ep%d", addr);
 829         d->epns[addr-1] = ep;
 830         ep->epn.g_idx = i;
 831         ep->epn.regs = vhub->regs + 0x200 + (i * 0x10);
 832
 833         ep->buf = dma_alloc_coherent(&vhub->pdev->dev,
 834                                      AST_VHUB_EPn_MAX_PACKET +
 835                                      8 * AST_VHUB_DESCS_COUNT,
 836                                      &ep->buf_dma, GFP_KERNEL);
 837         if (!ep->buf) {
 838                 kfree(ep->ep.name);
 839                 ep->ep.name = NULL;
 840                 return NULL;
 841         }
 842         ep->epn.descs = ep->buf + AST_VHUB_EPn_MAX_PACKET;
 843         ep->epn.descs_dma = ep->buf_dma + AST_VHUB_EPn_MAX_PACKET;
 844
 845         usb_ep_set_maxpacket_limit(&ep->ep, AST_VHUB_EPn_MAX_PACKET);
 846         list_add_tail(&ep->ep.ep_list, &d->gadget.ep_list);
 847         ep->ep.caps.type_iso = true;
 848         ep->ep.caps.type_bulk = true;
 849         ep->ep.caps.type_int = true;
 850         ep->ep.caps.dir_in = true;
 851         ep->ep.caps.dir_out = true;
 852
 853         return ep;
 854 }