drivers/usb/misc/uss720.c

   1 /*****************************************************************************/
   2
   3 /*
   4  *      uss720.c  --  USS720 USB Parport Cable.
   5  *
   6  *      Copyright (C) 1999, 2005, 2010
   7  *          Thomas Sailer (t.sailer@alumni.ethz.ch)
   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  *      This program is distributed in the hope that it will be useful,
  15  *      but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  *      GNU General Public License for more details.
  18  *
  19  *      You should have received a copy of the GNU General Public License
  20  *      along with this program; if not, write to the Free Software
  21  *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22  *
  23  *  Based on parport_pc.c
  24  *
  25  *  History:
  26  *   0.1  04.08.1999  Created
  27  *   0.2  07.08.1999  Some fixes mainly suggested by Tim Waugh
  28  *                    Interrupt handling currently disabled because
  29  *                    usb_request_irq crashes somewhere within ohci.c
  30  *                    for no apparent reason (that is for me, anyway)
  31  *                    ECP currently untested
  32  *   0.3  10.08.1999  fixing merge errors
  33  *   0.4  13.08.1999  Added Vendor/Product ID of Brad Hard's cable
  34  *   0.5  20.09.1999  usb_control_msg wrapper used
  35  *        Nov01.2000  usb_device_table support by Adam J. Richter
  36  *        08.04.2001  Identify version on module load.  gb
  37  *   0.6  02.09.2005  Fix "scheduling in interrupt" problem by making save/restore
  38  *                    context asynchronous
  39  *
  40  */
  41
  42 /*****************************************************************************/
  43
  44 #include <linux/module.h>
  45 #include <linux/socket.h>
  46 #include <linux/parport.h>
  47 #include <linux/init.h>
  48 #include <linux/usb.h>
  49 #include <linux/delay.h>
  50 #include <linux/completion.h>
  51 #include <linux/kref.h>
  52 #include <linux/slab.h>
  53 #include <linux/sched/signal.h>
  54
  55 #define DRIVER_AUTHOR "Thomas M. Sailer, t.sailer@alumni.ethz.ch"
  56 #define DRIVER_DESC "USB Parport Cable driver for Cables using the Lucent Technologies USS720 Chip"
  57
  58 /* --------------------------------------------------------------------- */
  59
  60 struct parport_uss720_private {
  61         struct usb_device *usbdev;
  62         struct parport *pp;
  63         struct kref ref_count;
  64         __u8 reg[7];  /* USB registers */
  65         struct list_head asynclist;
  66         spinlock_t asynclock;
  67 };
  68
  69 struct uss720_async_request {
  70         struct parport_uss720_private *priv;
  71         struct kref ref_count;
  72         struct list_head asynclist;
  73         struct completion compl;
  74         struct urb *urb;
  75         struct usb_ctrlrequest *dr;
  76         __u8 reg[7];
  77 };
  78
  79 /* --------------------------------------------------------------------- */
  80
  81 static void destroy_priv(struct kref *kref)
  82 {
  83         struct parport_uss720_private *priv = container_of(kref, struct parport_uss720_private, ref_count);
  84
  85         dev_dbg(&priv->usbdev->dev, "destroying priv datastructure\n");
  86         usb_put_dev(priv->usbdev);
  87         priv->usbdev = NULL;
  88         kfree(priv);
  89 }
  90
  91 static void destroy_async(struct kref *kref)
  92 {
  93         struct uss720_async_request *rq = container_of(kref, struct uss720_async_request, ref_count);
  94         struct parport_uss720_private *priv = rq->priv;
  95         unsigned long flags;
  96
  97         if (likely(rq->urb))
  98                 usb_free_urb(rq->urb);
  99         kfree(rq->dr);
 100         spin_lock_irqsave(&priv->asynclock, flags);
 101         list_del_init(&rq->asynclist);
 102         spin_unlock_irqrestore(&priv->asynclock, flags);
 103         kfree(rq);
 104         kref_put(&priv->ref_count, destroy_priv);
 105 }
 106
 107 /* --------------------------------------------------------------------- */
 108
 109 static void async_complete(struct urb *urb)
 110 {
 111         struct uss720_async_request *rq;
 112         struct parport *pp;
 113         struct parport_uss720_private *priv;
 114         int status = urb->status;
 115
 116         rq = urb->context;
 117         priv = rq->priv;
 118         pp = priv->pp;
 119         if (status) {
 120                 dev_err(&urb->dev->dev, "async_complete: urb error %d\n",
 121                         status);
 122         } else if (rq->dr->bRequest == 3) {
 123                 memcpy(priv->reg, rq->reg, sizeof(priv->reg));
 124 #if 0
 125                 dev_dbg(&priv->usbdev->dev, "async_complete regs %7ph\n",
 126                         priv->reg);
 127 #endif
 128                 /* if nAck interrupts are enabled and we have an interrupt, call the interrupt procedure */
 129                 if (rq->reg[2] & rq->reg[1] & 0x10 && pp)
 130                         parport_generic_irq(pp);
 131         }
 132         complete(&rq->compl);
 133         kref_put(&rq->ref_count, destroy_async);
 134 }
 135
 136 static struct uss720_async_request *submit_async_request(struct parport_uss720_private *priv,
 137                                                          __u8 request, __u8 requesttype, __u16 value, __u16 index,
 138                                                          gfp_t mem_flags)
 139 {
 140         struct usb_device *usbdev;
 141         struct uss720_async_request *rq;
 142         unsigned long flags;
 143         int ret;
 144
 145         if (!priv)
 146                 return NULL;
 147         usbdev = priv->usbdev;
 148         if (!usbdev)
 149                 return NULL;
 150         rq = kzalloc(sizeof(struct uss720_async_request), mem_flags);
 151         if (!rq)
 152                 return NULL;
 153         kref_init(&rq->ref_count);
 154         INIT_LIST_HEAD(&rq->asynclist);
 155         init_completion(&rq->compl);
 156         kref_get(&priv->ref_count);
 157         rq->priv = priv;
 158         rq->urb = usb_alloc_urb(0, mem_flags);
 159         if (!rq->urb) {
 160                 kref_put(&rq->ref_count, destroy_async);
 161                 return NULL;
 162         }
 163         rq->dr = kmalloc(sizeof(*rq->dr), mem_flags);
 164         if (!rq->dr) {
 165                 kref_put(&rq->ref_count, destroy_async);
 166                 return NULL;
 167         }
 168         rq->dr->bRequestType = requesttype;
 169         rq->dr->bRequest = request;
 170         rq->dr->wValue = cpu_to_le16(value);
 171         rq->dr->wIndex = cpu_to_le16(index);
 172         rq->dr->wLength = cpu_to_le16((request == 3) ? sizeof(rq->reg) : 0);
 173         usb_fill_control_urb(rq->urb, usbdev, (requesttype & 0x80) ? usb_rcvctrlpipe(usbdev, 0) : usb_sndctrlpipe(usbdev, 0),
 174                              (unsigned char *)rq->dr,
 175                              (request == 3) ? rq->reg : NULL, (request == 3) ? sizeof(rq->reg) : 0, async_complete, rq);
 176         /* rq->urb->transfer_flags |= URB_ASYNC_UNLINK; */
 177         spin_lock_irqsave(&priv->asynclock, flags);
 178         list_add_tail(&rq->asynclist, &priv->asynclist);
 179         spin_unlock_irqrestore(&priv->asynclock, flags);
 180         kref_get(&rq->ref_count);
 181         ret = usb_submit_urb(rq->urb, mem_flags);
 182         if (!ret)
 183                 return rq;
 184         destroy_async(&rq->ref_count);
 185         dev_err(&usbdev->dev, "submit_async_request submit_urb failed with %d\n", ret);
 186         return NULL;
 187 }
 188
 189 static unsigned int kill_all_async_requests_priv(struct parport_uss720_private *priv)
 190 {
 191         struct uss720_async_request *rq;
 192         unsigned long flags;
 193         unsigned int ret = 0;
 194
 195         spin_lock_irqsave(&priv->asynclock, flags);
 196         list_for_each_entry(rq, &priv->asynclist, asynclist) {
 197                 usb_unlink_urb(rq->urb);
 198                 ret++;
 199         }
 200         spin_unlock_irqrestore(&priv->asynclock, flags);
 201         return ret;
 202 }
 203
 204 /* --------------------------------------------------------------------- */
 205
 206 static int get_1284_register(struct parport *pp, unsigned char reg, unsigned char *val, gfp_t mem_flags)
 207 {
 208         struct parport_uss720_private *priv;
 209         struct uss720_async_request *rq;
 210         static const unsigned char regindex[9] = {
 211                 4, 0, 1, 5, 5, 0, 2, 3, 6
 212         };
 213         int ret;
 214
 215         if (!pp)
 216                 return -EIO;
 217         priv = pp->private_data;
 218         rq = submit_async_request(priv, 3, 0xc0, ((unsigned int)reg) << 8, 0, mem_flags);
 219         if (!rq) {
 220                 dev_err(&priv->usbdev->dev, "get_1284_register(%u) failed",
 221                         (unsigned int)reg);
 222                 return -EIO;
 223         }
 224         if (!val) {
 225                 kref_put(&rq->ref_count, destroy_async);
 226                 return 0;
 227         }
 228         if (wait_for_completion_timeout(&rq->compl, HZ)) {
 229                 ret = rq->urb->status;
 230                 *val = priv->reg[(reg >= 9) ? 0 : regindex[reg]];
 231                 if (ret)
 232                         printk(KERN_WARNING "get_1284_register: "
 233                                "usb error %d\n", ret);
 234                 kref_put(&rq->ref_count, destroy_async);
 235                 return ret;
 236         }
 237         printk(KERN_WARNING "get_1284_register timeout\n");
 238         kill_all_async_requests_priv(priv);
 239         return -EIO;
 240 }
 241
 242 static int set_1284_register(struct parport *pp, unsigned char reg, unsigned char val, gfp_t mem_flags)
 243 {
 244         struct parport_uss720_private *priv;
 245         struct uss720_async_request *rq;
 246
 247         if (!pp)
 248                 return -EIO;
 249         priv = pp->private_data;
 250         rq = submit_async_request(priv, 4, 0x40, (((unsigned int)reg) << 8) | val, 0, mem_flags);
 251         if (!rq) {
 252                 dev_err(&priv->usbdev->dev, "set_1284_register(%u,%u) failed",
 253                         (unsigned int)reg, (unsigned int)val);
 254                 return -EIO;
 255         }
 256         kref_put(&rq->ref_count, destroy_async);
 257         return 0;
 258 }
 259
 260 /* --------------------------------------------------------------------- */
 261
 262 /* ECR modes */
 263 #define ECR_SPP 00
 264 #define ECR_PS2 01
 265 #define ECR_PPF 02
 266 #define ECR_ECP 03
 267 #define ECR_EPP 04
 268
 269 /* Safely change the mode bits in the ECR */
 270 static int change_mode(struct parport *pp, int m)
 271 {
 272         struct parport_uss720_private *priv = pp->private_data;
 273         int mode;
 274         __u8 reg;
 275
 276         if (get_1284_register(pp, 6, &reg, GFP_KERNEL))
 277                 return -EIO;
 278         /* Bits <7:5> contain the mode. */
 279         mode = (priv->reg[2] >> 5) & 0x7;
 280         if (mode == m)
 281                 return 0;
 282         /* We have to go through mode 000 or 001 */
 283         if (mode > ECR_PS2 && m > ECR_PS2)
 284                 if (change_mode(pp, ECR_PS2))
 285                         return -EIO;
 286
 287         if (m <= ECR_PS2 && !(priv->reg[1] & 0x20)) {
 288                 /* This mode resets the FIFO, so we may
 289                  * have to wait for it to drain first. */
 290                 unsigned long expire = jiffies + pp->physport->cad->timeout;
 291                 switch (mode) {
 292                 case ECR_PPF: /* Parallel Port FIFO mode */
 293                 case ECR_ECP: /* ECP Parallel Port mode */
 294                         /* Poll slowly. */
 295                         for (;;) {
 296                                 if (get_1284_register(pp, 6, &reg, GFP_KERNEL))
 297                                         return -EIO;
 298                                 if (priv->reg[2] & 0x01)
 299                                         break;
 300                                 if (time_after_eq (jiffies, expire))
 301                                         /* The FIFO is stuck. */
 302                                         return -EBUSY;
 303                                 msleep_interruptible(10);
 304                                 if (signal_pending (current))
 305                                         break;
 306                         }
 307                 }
 308         }
 309         /* Set the mode. */
 310         if (set_1284_register(pp, 6, m << 5, GFP_KERNEL))
 311                 return -EIO;
 312         if (get_1284_register(pp, 6, &reg, GFP_KERNEL))
 313                 return -EIO;
 314         return 0;
 315 }
 316
 317 /*
 318  * Clear TIMEOUT BIT in EPP MODE
 319  */
 320 static int clear_epp_timeout(struct parport *pp)
 321 {
 322         unsigned char stat;
 323
 324         if (get_1284_register(pp, 1, &stat, GFP_KERNEL))
 325                 return 1;
 326         return stat & 1;
 327 }
 328
 329 /*
 330  * Access functions.
 331  */
 332 #if 0
 333 static int uss720_irq(int usbstatus, void *buffer, int len, void *dev_id)
 334 {
 335         struct parport *pp = (struct parport *)dev_id;
 336         struct parport_uss720_private *priv = pp->private_data;
 337
 338         if (usbstatus != 0 || len < 4 || !buffer)
 339                 return 1;
 340         memcpy(priv->reg, buffer, 4);
 341         /* if nAck interrupts are enabled and we have an interrupt, call the interrupt procedure */
 342         if (priv->reg[2] & priv->reg[1] & 0x10)
 343                 parport_generic_irq(pp);
 344         return 1;
 345 }
 346 #endif
 347
 348 static void parport_uss720_write_data(struct parport *pp, unsigned char d)
 349 {
 350         set_1284_register(pp, 0, d, GFP_KERNEL);
 351 }
 352
 353 static unsigned char parport_uss720_read_data(struct parport *pp)
 354 {
 355         unsigned char ret;
 356
 357         if (get_1284_register(pp, 0, &ret, GFP_KERNEL))
 358                 return 0;
 359         return ret;
 360 }
 361
 362 static void parport_uss720_write_control(struct parport *pp, unsigned char d)
 363 {
 364         struct parport_uss720_private *priv = pp->private_data;
 365
 366         d = (d & 0xf) | (priv->reg[1] & 0xf0);
 367         if (set_1284_register(pp, 2, d, GFP_KERNEL))
 368                 return;
 369         priv->reg[1] = d;
 370 }
 371
 372 static unsigned char parport_uss720_read_control(struct parport *pp)
 373 {
 374         struct parport_uss720_private *priv = pp->private_data;
 375         return priv->reg[1] & 0xf; /* Use soft copy */
 376 }
 377
 378 static unsigned char parport_uss720_frob_control(struct parport *pp, unsigned char mask, unsigned char val)
 379 {
 380         struct parport_uss720_private *priv = pp->private_data;
 381         unsigned char d;
 382
 383         mask &= 0x0f;
 384         val &= 0x0f;
 385         d = (priv->reg[1] & (~mask)) ^ val;
 386         if (set_1284_register(pp, 2, d, GFP_ATOMIC))
 387                 return 0;
 388         priv->reg[1] = d;
 389         return d & 0xf;
 390 }
 391
 392 static unsigned char parport_uss720_read_status(struct parport *pp)
 393 {
 394         unsigned char ret;
 395
 396         if (get_1284_register(pp, 1, &ret, GFP_ATOMIC))
 397                 return 0;
 398         return ret & 0xf8;
 399 }
 400
 401 static void parport_uss720_disable_irq(struct parport *pp)
 402 {
 403         struct parport_uss720_private *priv = pp->private_data;
 404         unsigned char d;
 405
 406         d = priv->reg[1] & ~0x10;
 407         if (set_1284_register(pp, 2, d, GFP_KERNEL))
 408                 return;
 409         priv->reg[1] = d;
 410 }
 411
 412 static void parport_uss720_enable_irq(struct parport *pp)
 413 {
 414         struct parport_uss720_private *priv = pp->private_data;
 415         unsigned char d;
 416
 417         d = priv->reg[1] | 0x10;
 418         if (set_1284_register(pp, 2, d, GFP_KERNEL))
 419                 return;
 420         priv->reg[1] = d;
 421 }
 422
 423 static void parport_uss720_data_forward (struct parport *pp)
 424 {
 425         struct parport_uss720_private *priv = pp->private_data;
 426         unsigned char d;
 427
 428         d = priv->reg[1] & ~0x20;
 429         if (set_1284_register(pp, 2, d, GFP_KERNEL))
 430                 return;
 431         priv->reg[1] = d;
 432 }
 433
 434 static void parport_uss720_data_reverse (struct parport *pp)
 435 {
 436         struct parport_uss720_private *priv = pp->private_data;
 437         unsigned char d;
 438
 439         d = priv->reg[1] | 0x20;
 440         if (set_1284_register(pp, 2, d, GFP_KERNEL))
 441                 return;
 442         priv->reg[1] = d;
 443 }
 444
 445 static void parport_uss720_init_state(struct pardevice *dev, struct parport_state *s)
 446 {
 447         s->u.pc.ctr = 0xc | (dev->irq_func ? 0x10 : 0x0);
 448         s->u.pc.ecr = 0x24;
 449 }
 450
 451 static void parport_uss720_save_state(struct parport *pp, struct parport_state *s)
 452 {
 453         struct parport_uss720_private *priv = pp->private_data;
 454
 455 #if 0
 456         if (get_1284_register(pp, 2, NULL, GFP_ATOMIC))
 457                 return;
 458 #endif
 459         s->u.pc.ctr = priv->reg[1];
 460         s->u.pc.ecr = priv->reg[2];
 461 }
 462
 463 static void parport_uss720_restore_state(struct parport *pp, struct parport_state *s)
 464 {
 465         struct parport_uss720_private *priv = pp->private_data;
 466
 467         set_1284_register(pp, 2, s->u.pc.ctr, GFP_ATOMIC);
 468         set_1284_register(pp, 6, s->u.pc.ecr, GFP_ATOMIC);
 469         get_1284_register(pp, 2, NULL, GFP_ATOMIC);
 470         priv->reg[1] = s->u.pc.ctr;
 471         priv->reg[2] = s->u.pc.ecr;
 472 }
 473
 474 static size_t parport_uss720_epp_read_data(struct parport *pp, void *buf, size_t length, int flags)
 475 {
 476         struct parport_uss720_private *priv = pp->private_data;
 477         size_t got = 0;
 478
 479         if (change_mode(pp, ECR_EPP))
 480                 return 0;
 481         for (; got < length; got++) {
 482                 if (get_1284_register(pp, 4, (char *)buf, GFP_KERNEL))
 483                         break;
 484                 buf++;
 485                 if (priv->reg[0] & 0x01) {
 486                         clear_epp_timeout(pp);
 487                         break;
 488                 }
 489         }
 490         change_mode(pp, ECR_PS2);
 491         return got;
 492 }
 493
 494 static size_t parport_uss720_epp_write_data(struct parport *pp, const void *buf, size_t length, int flags)
 495 {
 496 #if 0
 497         struct parport_uss720_private *priv = pp->private_data;
 498         size_t written = 0;
 499
 500         if (change_mode(pp, ECR_EPP))
 501                 return 0;
 502         for (; written < length; written++) {
 503                 if (set_1284_register(pp, 4, (char *)buf, GFP_KERNEL))
 504                         break;
 505                 ((char*)buf)++;
 506                 if (get_1284_register(pp, 1, NULL, GFP_KERNEL))
 507                         break;
 508                 if (priv->reg[0] & 0x01) {
 509                         clear_epp_timeout(pp);
 510                         break;
 511                 }
 512         }
 513         change_mode(pp, ECR_PS2);
 514         return written;
 515 #else
 516         struct parport_uss720_private *priv = pp->private_data;
 517         struct usb_device *usbdev = priv->usbdev;
 518         int rlen;
 519         int i;
 520
 521         if (!usbdev)
 522                 return 0;
 523         if (change_mode(pp, ECR_EPP))
 524                 return 0;
 525         i = usb_bulk_msg(usbdev, usb_sndbulkpipe(usbdev, 1), (void *)buf, length, &rlen, 20000);
 526         if (i)
 527                 printk(KERN_ERR "uss720: sendbulk ep 1 buf %p len %zu rlen %u\n", buf, length, rlen);
 528         change_mode(pp, ECR_PS2);
 529         return rlen;
 530 #endif
 531 }
 532
 533 static size_t parport_uss720_epp_read_addr(struct parport *pp, void *buf, size_t length, int flags)
 534 {
 535         struct parport_uss720_private *priv = pp->private_data;
 536         size_t got = 0;
 537
 538         if (change_mode(pp, ECR_EPP))
 539                 return 0;
 540         for (; got < length; got++) {
 541                 if (get_1284_register(pp, 3, (char *)buf, GFP_KERNEL))
 542                         break;
 543                 buf++;
 544                 if (priv->reg[0] & 0x01) {
 545                         clear_epp_timeout(pp);
 546                         break;
 547                 }
 548         }
 549         change_mode(pp, ECR_PS2);
 550         return got;
 551 }
 552
 553 static size_t parport_uss720_epp_write_addr(struct parport *pp, const void *buf, size_t length, int flags)
 554 {
 555         struct parport_uss720_private *priv = pp->private_data;
 556         size_t written = 0;
 557
 558         if (change_mode(pp, ECR_EPP))
 559                 return 0;
 560         for (; written < length; written++) {
 561                 if (set_1284_register(pp, 3, *(char *)buf, GFP_KERNEL))
 562                         break;
 563                 buf++;
 564                 if (get_1284_register(pp, 1, NULL, GFP_KERNEL))
 565                         break;
 566                 if (priv->reg[0] & 0x01) {
 567                         clear_epp_timeout(pp);
 568                         break;
 569                 }
 570         }
 571         change_mode(pp, ECR_PS2);
 572         return written;
 573 }
 574
 575 static size_t parport_uss720_ecp_write_data(struct parport *pp, const void *buffer, size_t len, int flags)
 576 {
 577         struct parport_uss720_private *priv = pp->private_data;
 578         struct usb_device *usbdev = priv->usbdev;
 579         int rlen;
 580         int i;
 581
 582         if (!usbdev)
 583                 return 0;
 584         if (change_mode(pp, ECR_ECP))
 585                 return 0;
 586         i = usb_bulk_msg(usbdev, usb_sndbulkpipe(usbdev, 1), (void *)buffer, len, &rlen, 20000);
 587         if (i)
 588                 printk(KERN_ERR "uss720: sendbulk ep 1 buf %p len %zu rlen %u\n", buffer, len, rlen);
 589         change_mode(pp, ECR_PS2);
 590         return rlen;
 591 }
 592
 593 static size_t parport_uss720_ecp_read_data(struct parport *pp, void *buffer, size_t len, int flags)
 594 {
 595         struct parport_uss720_private *priv = pp->private_data;
 596         struct usb_device *usbdev = priv->usbdev;
 597         int rlen;
 598         int i;
 599
 600         if (!usbdev)
 601                 return 0;
 602         if (change_mode(pp, ECR_ECP))
 603                 return 0;
 604         i = usb_bulk_msg(usbdev, usb_rcvbulkpipe(usbdev, 2), buffer, len, &rlen, 20000);
 605         if (i)
 606                 printk(KERN_ERR "uss720: recvbulk ep 2 buf %p len %zu rlen %u\n", buffer, len, rlen);
 607         change_mode(pp, ECR_PS2);
 608         return rlen;
 609 }
 610
 611 static size_t parport_uss720_ecp_write_addr(struct parport *pp, const void *buffer, size_t len, int flags)
 612 {
 613         size_t written = 0;
 614
 615         if (change_mode(pp, ECR_ECP))
 616                 return 0;
 617         for (; written < len; written++) {
 618                 if (set_1284_register(pp, 5, *(char *)buffer, GFP_KERNEL))
 619                         break;
 620                 buffer++;
 621         }
 622         change_mode(pp, ECR_PS2);
 623         return written;
 624 }
 625
 626 static size_t parport_uss720_write_compat(struct parport *pp, const void *buffer, size_t len, int flags)
 627 {
 628         struct parport_uss720_private *priv = pp->private_data;
 629         struct usb_device *usbdev = priv->usbdev;
 630         int rlen;
 631         int i;
 632
 633         if (!usbdev)
 634                 return 0;
 635         if (change_mode(pp, ECR_PPF))
 636                 return 0;
 637         i = usb_bulk_msg(usbdev, usb_sndbulkpipe(usbdev, 1), (void *)buffer, len, &rlen, 20000);
 638         if (i)
 639                 printk(KERN_ERR "uss720: sendbulk ep 1 buf %p len %zu rlen %u\n", buffer, len, rlen);
 640         change_mode(pp, ECR_PS2);
 641         return rlen;
 642 }
 643
 644 /* --------------------------------------------------------------------- */
 645
 646 static struct parport_operations parport_uss720_ops =
 647 {
 648         .owner =                THIS_MODULE,
 649         .write_data =           parport_uss720_write_data,
 650         .read_data =            parport_uss720_read_data,
 651
 652         .write_control =        parport_uss720_write_control,
 653         .read_control =         parport_uss720_read_control,
 654         .frob_control =         parport_uss720_frob_control,
 655
 656         .read_status =          parport_uss720_read_status,
 657
 658         .enable_irq =           parport_uss720_enable_irq,
 659         .disable_irq =          parport_uss720_disable_irq,
 660
 661         .data_forward =         parport_uss720_data_forward,
 662         .data_reverse =         parport_uss720_data_reverse,
 663
 664         .init_state =           parport_uss720_init_state,
 665         .save_state =           parport_uss720_save_state,
 666         .restore_state =        parport_uss720_restore_state,
 667
 668         .epp_write_data =       parport_uss720_epp_write_data,
 669         .epp_read_data =        parport_uss720_epp_read_data,
 670         .epp_write_addr =       parport_uss720_epp_write_addr,
 671         .epp_read_addr =        parport_uss720_epp_read_addr,
 672
 673         .ecp_write_data =       parport_uss720_ecp_write_data,
 674         .ecp_read_data =        parport_uss720_ecp_read_data,
 675         .ecp_write_addr =       parport_uss720_ecp_write_addr,
 676
 677         .compat_write_data =    parport_uss720_write_compat,
 678         .nibble_read_data =     parport_ieee1284_read_nibble,
 679         .byte_read_data =       parport_ieee1284_read_byte,
 680 };
 681
 682 /* --------------------------------------------------------------------- */
 683
 684 static int uss720_probe(struct usb_interface *intf,
 685                         const struct usb_device_id *id)
 686 {
 687         struct usb_device *usbdev = usb_get_dev(interface_to_usbdev(intf));
 688         struct usb_host_interface *interface;
 689         struct usb_endpoint_descriptor *epd;
 690         struct parport_uss720_private *priv;
 691         struct parport *pp;
 692         unsigned char reg;
 693         int i;
 694
 695         dev_dbg(&intf->dev, "probe: vendor id 0x%x, device id 0x%x\n",
 696                 le16_to_cpu(usbdev->descriptor.idVendor),
 697                 le16_to_cpu(usbdev->descriptor.idProduct));
 698
 699         /* our known interfaces have 3 alternate settings */
 700         if (intf->num_altsetting != 3) {
 701                 usb_put_dev(usbdev);
 702                 return -ENODEV;
 703         }
 704         i = usb_set_interface(usbdev, intf->altsetting->desc.bInterfaceNumber, 2);
 705         dev_dbg(&intf->dev, "set interface result %d\n", i);
 706
 707         interface = intf->cur_altsetting;
 708
 709         if (interface->desc.bNumEndpoints < 3) {
 710                 usb_put_dev(usbdev);
 711                 return -ENODEV;
 712         }
 713
 714         /*
 715          * Allocate parport interface
 716          */
 717         priv = kzalloc(sizeof(struct parport_uss720_private), GFP_KERNEL);
 718         if (!priv) {
 719                 usb_put_dev(usbdev);
 720                 return -ENOMEM;
 721         }
 722         priv->pp = NULL;
 723         priv->usbdev = usbdev;
 724         kref_init(&priv->ref_count);
 725         spin_lock_init(&priv->asynclock);
 726         INIT_LIST_HEAD(&priv->asynclist);
 727         pp = parport_register_port(0, PARPORT_IRQ_NONE, PARPORT_DMA_NONE, &parport_uss720_ops);
 728         if (!pp) {
 729                 printk(KERN_WARNING "uss720: could not register parport\n");
 730                 goto probe_abort;
 731         }
 732
 733         priv->pp = pp;
 734         pp->private_data = priv;
 735         pp->modes = PARPORT_MODE_PCSPP | PARPORT_MODE_TRISTATE | PARPORT_MODE_EPP | PARPORT_MODE_ECP | PARPORT_MODE_COMPAT;
 736
 737         /* set the USS720 control register to manual mode, no ECP compression, enable all ints */
 738         set_1284_register(pp, 7, 0x00, GFP_KERNEL);
 739         set_1284_register(pp, 6, 0x30, GFP_KERNEL);  /* PS/2 mode */
 740         set_1284_register(pp, 2, 0x0c, GFP_KERNEL);
 741         /* debugging */
 742         get_1284_register(pp, 0, &reg, GFP_KERNEL);
 743         dev_dbg(&intf->dev, "reg: %7ph\n", priv->reg);
 744
 745         i = usb_find_last_int_in_endpoint(interface, &epd);
 746         if (!i) {
 747                 dev_dbg(&intf->dev, "epaddr %d interval %d\n",
 748                                 epd->bEndpointAddress, epd->bInterval);
 749         }
 750         parport_announce_port(pp);
 751
 752         usb_set_intfdata(intf, pp);
 753         return 0;
 754
 755 probe_abort:
 756         kill_all_async_requests_priv(priv);
 757         kref_put(&priv->ref_count, destroy_priv);
 758         return -ENODEV;
 759 }
 760
 761 static void uss720_disconnect(struct usb_interface *intf)
 762 {
 763         struct parport *pp = usb_get_intfdata(intf);
 764         struct parport_uss720_private *priv;
 765         struct usb_device *usbdev;
 766
 767         dev_dbg(&intf->dev, "disconnect\n");
 768         usb_set_intfdata(intf, NULL);
 769         if (pp) {
 770                 priv = pp->private_data;
 771                 usbdev = priv->usbdev;
 772                 priv->pp = NULL;
 773                 dev_dbg(&intf->dev, "parport_remove_port\n");
 774                 parport_remove_port(pp);
 775                 parport_put_port(pp);
 776                 kill_all_async_requests_priv(priv);
 777                 kref_put(&priv->ref_count, destroy_priv);
 778         }
 779         dev_dbg(&intf->dev, "disconnect done\n");
 780 }
 781
 782 /* table of cables that work through this driver */
 783 static const struct usb_device_id uss720_table[] = {
 784         { USB_DEVICE(0x047e, 0x1001) },
 785         { USB_DEVICE(0x0557, 0x2001) },
 786         { USB_DEVICE(0x0729, 0x1284) },
 787         { USB_DEVICE(0x1293, 0x0002) },
 788         { USB_DEVICE(0x050d, 0x0002) },
 789         { }                                             /* Terminating entry */
 790 };
 791
 792 MODULE_DEVICE_TABLE (usb, uss720_table);
 793
 794
 795 static struct usb_driver uss720_driver = {
 796         .name =         "uss720",
 797         .probe =        uss720_probe,
 798         .disconnect =   uss720_disconnect,
 799         .id_table =     uss720_table,
 800 };
 801
 802 /* --------------------------------------------------------------------- */
 803
 804 MODULE_AUTHOR(DRIVER_AUTHOR);
 805 MODULE_DESCRIPTION(DRIVER_DESC);
 806 MODULE_LICENSE("GPL");
 807
 808 static int __init uss720_init(void)
 809 {
 810         int retval;
 811         retval = usb_register(&uss720_driver);
 812         if (retval)
 813                 goto out;
 814
 815         printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_DESC "\n");
 816         printk(KERN_INFO KBUILD_MODNAME ": NOTE: this is a special purpose "
 817                "driver to allow nonstandard\n");
 818         printk(KERN_INFO KBUILD_MODNAME ": protocols (eg. bitbang) over "
 819                "USS720 usb to parallel cables\n");
 820         printk(KERN_INFO KBUILD_MODNAME ": If you just want to connect to a "
 821                "printer, use usblp instead\n");
 822 out:
 823         return retval;
 824 }
 825
 826 static void __exit uss720_cleanup(void)
 827 {
 828         usb_deregister(&uss720_driver);
 829 }
 830
 831 module_init(uss720_init);
 832 module_exit(uss720_cleanup);
 833
 834 /* --------------------------------------------------------------------- */