1 /* 2 * LEGO USB Tower driver 3 * 4 * Copyright (C) 2003 David Glance <davidgsf@sourceforge.net> 5 * 2001-2004 Juergen Stuber <starblue@users.sourceforge.net> 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License as 9 * published by the Free Software Foundation; either version 2 of 10 * the License, or (at your option) any later version. 11 * 12 * derived from USB Skeleton driver - 0.5 13 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com) 14 * 15 * History: 16 * 17 * 2001-10-13 - 0.1 js 18 * - first version 19 * 2001-11-03 - 0.2 js 20 * - simplified buffering, one-shot URBs for writing 21 * 2001-11-10 - 0.3 js 22 * - removed IOCTL (setting power/mode is more complicated, postponed) 23 * 2001-11-28 - 0.4 js 24 * - added vendor commands for mode of operation and power level in open 25 * 2001-12-04 - 0.5 js 26 * - set IR mode by default (by oversight 0.4 set VLL mode) 27 * 2002-01-11 - 0.5? pcchan 28 * - make read buffer reusable and work around bytes_to_write issue between 29 * uhci and legusbtower 30 * 2002-09-23 - 0.52 david (david@csse.uwa.edu.au) 31 * - imported into lejos project 32 * - changed wake_up to wake_up_interruptible 33 * - changed to use lego0 rather than tower0 34 * - changed dbg() to use __func__ rather than deprecated __func__ 35 * 2003-01-12 - 0.53 david (david@csse.uwa.edu.au) 36 * - changed read and write to write everything or 37 * timeout (from a patch by Chris Riesen and Brett Thaeler driver) 38 * - added ioctl functionality to set timeouts 39 * 2003-07-18 - 0.54 davidgsf (david@csse.uwa.edu.au) 40 * - initial import into LegoUSB project 41 * - merge of existing LegoUSB.c driver 42 * 2003-07-18 - 0.56 davidgsf (david@csse.uwa.edu.au) 43 * - port to 2.6 style driver 44 * 2004-02-29 - 0.6 Juergen Stuber <starblue@users.sourceforge.net> 45 * - fix locking 46 * - unlink read URBs which are no longer needed 47 * - allow increased buffer size, eliminates need for timeout on write 48 * - have read URB running continuously 49 * - added poll 50 * - forbid seeking 51 * - added nonblocking I/O 52 * - changed back __func__ to __func__ 53 * - read and log tower firmware version 54 * - reset tower on probe, avoids failure of first write 55 * 2004-03-09 - 0.7 Juergen Stuber <starblue@users.sourceforge.net> 56 * - timeout read now only after inactivity, shorten default accordingly 57 * 2004-03-11 - 0.8 Juergen Stuber <starblue@users.sourceforge.net> 58 * - log major, minor instead of possibly confusing device filename 59 * - whitespace cleanup 60 * 2004-03-12 - 0.9 Juergen Stuber <starblue@users.sourceforge.net> 61 * - normalize whitespace in debug messages 62 * - take care about endianness in control message responses 63 * 2004-03-13 - 0.91 Juergen Stuber <starblue@users.sourceforge.net> 64 * - make default intervals longer to accommodate current EHCI driver 65 * 2004-03-19 - 0.92 Juergen Stuber <starblue@users.sourceforge.net> 66 * - replaced atomic_t by memory barriers 67 * 2004-04-21 - 0.93 Juergen Stuber <starblue@users.sourceforge.net> 68 * - wait for completion of write urb in release (needed for remotecontrol) 69 * - corrected poll for write direction (missing negation) 70 * 2004-04-22 - 0.94 Juergen Stuber <starblue@users.sourceforge.net> 71 * - make device locking interruptible 72 * 2004-04-30 - 0.95 Juergen Stuber <starblue@users.sourceforge.net> 73 * - check for valid udev on resubmitting and unlinking urbs 74 * 2004-08-03 - 0.96 Juergen Stuber <starblue@users.sourceforge.net> 75 * - move reset into open to clean out spurious data 76 */ 77 78 #include <linux/kernel.h> 79 #include <linux/errno.h> 80 #include <linux/init.h> 81 #include <linux/slab.h> 82 #include <linux/module.h> 83 #include <linux/completion.h> 84 #include <linux/mutex.h> 85 #include <asm/uaccess.h> 86 #include <linux/usb.h> 87 #include <linux/poll.h> 88 89 90 #ifdef CONFIG_USB_DEBUG 91 static int debug = 4; 92 #else 93 static int debug = 0; 94 #endif 95 96 /* Use our own dbg macro */ 97 #undef dbg 98 #define dbg(lvl, format, arg...) \ 99 do { \ 100 if (debug >= lvl) \ 101 printk(KERN_DEBUG "%s: " format "\n", __FILE__, ##arg); \ 102 } while (0) 103 104 /* Version Information */ 105 #define DRIVER_VERSION "v0.96" 106 #define DRIVER_AUTHOR "Juergen Stuber <starblue@sourceforge.net>" 107 #define DRIVER_DESC "LEGO USB Tower Driver" 108 109 /* Module parameters */ 110 module_param(debug, int, S_IRUGO | S_IWUSR); 111 MODULE_PARM_DESC(debug, "Debug enabled or not"); 112 113 /* The defaults are chosen to work with the latest versions of leJOS and NQC. 114 */ 115 116 /* Some legacy software likes to receive packets in one piece. 117 * In this case read_buffer_size should exceed the maximal packet length 118 * (417 for datalog uploads), and packet_timeout should be set. 119 */ 120 static int read_buffer_size = 480; 121 module_param(read_buffer_size, int, 0); 122 MODULE_PARM_DESC(read_buffer_size, "Read buffer size"); 123 124 /* Some legacy software likes to send packets in one piece. 125 * In this case write_buffer_size should exceed the maximal packet length 126 * (417 for firmware and program downloads). 127 * A problem with long writes is that the following read may time out 128 * if the software is not prepared to wait long enough. 129 */ 130 static int write_buffer_size = 480; 131 module_param(write_buffer_size, int, 0); 132 MODULE_PARM_DESC(write_buffer_size, "Write buffer size"); 133 134 /* Some legacy software expects reads to contain whole LASM packets. 135 * To achieve this, characters which arrive before a packet timeout 136 * occurs will be returned in a single read operation. 137 * A problem with long reads is that the software may time out 138 * if it is not prepared to wait long enough. 139 * The packet timeout should be greater than the time between the 140 * reception of subsequent characters, which should arrive about 141 * every 5ms for the standard 2400 baud. 142 * Set it to 0 to disable. 143 */ 144 static int packet_timeout = 50; 145 module_param(packet_timeout, int, 0); 146 MODULE_PARM_DESC(packet_timeout, "Packet timeout in ms"); 147 148 /* Some legacy software expects blocking reads to time out. 149 * Timeout occurs after the specified time of read and write inactivity. 150 * Set it to 0 to disable. 151 */ 152 static int read_timeout = 200; 153 module_param(read_timeout, int, 0); 154 MODULE_PARM_DESC(read_timeout, "Read timeout in ms"); 155 156 /* As of kernel version 2.6.4 ehci-hcd uses an 157 * "only one interrupt transfer per frame" shortcut 158 * to simplify the scheduling of periodic transfers. 159 * This conflicts with our standard 1ms intervals for in and out URBs. 160 * We use default intervals of 2ms for in and 8ms for out transfers, 161 * which is fast enough for 2400 baud and allows a small additional load. 162 * Increase the interval to allow more devices that do interrupt transfers, 163 * or set to 0 to use the standard interval from the endpoint descriptors. 164 */ 165 static int interrupt_in_interval = 2; 166 module_param(interrupt_in_interval, int, 0); 167 MODULE_PARM_DESC(interrupt_in_interval, "Interrupt in interval in ms"); 168 169 static int interrupt_out_interval = 8; 170 module_param(interrupt_out_interval, int, 0); 171 MODULE_PARM_DESC(interrupt_out_interval, "Interrupt out interval in ms"); 172 173 /* Define these values to match your device */ 174 #define LEGO_USB_TOWER_VENDOR_ID 0x0694 175 #define LEGO_USB_TOWER_PRODUCT_ID 0x0001 176 177 /* Vendor requests */ 178 #define LEGO_USB_TOWER_REQUEST_RESET 0x04 179 #define LEGO_USB_TOWER_REQUEST_GET_VERSION 0xFD 180 181 struct tower_reset_reply { 182 __le16 size; /* little-endian */ 183 __u8 err_code; 184 __u8 spare; 185 } __attribute__ ((packed)); 186 187 struct tower_get_version_reply { 188 __le16 size; /* little-endian */ 189 __u8 err_code; 190 __u8 spare; 191 __u8 major; 192 __u8 minor; 193 __le16 build_no; /* little-endian */ 194 } __attribute__ ((packed)); 195 196 197 /* table of devices that work with this driver */ 198 static const struct usb_device_id tower_table[] = { 199 { USB_DEVICE(LEGO_USB_TOWER_VENDOR_ID, LEGO_USB_TOWER_PRODUCT_ID) }, 200 { } /* Terminating entry */ 201 }; 202 203 MODULE_DEVICE_TABLE (usb, tower_table); 204 static DEFINE_MUTEX(open_disc_mutex); 205 206 #define LEGO_USB_TOWER_MINOR_BASE 160 207 208 209 /* Structure to hold all of our device specific stuff */ 210 struct lego_usb_tower { 211 struct mutex lock; /* locks this structure */ 212 struct usb_device* udev; /* save off the usb device pointer */ 213 unsigned char minor; /* the starting minor number for this device */ 214 215 int open_count; /* number of times this port has been opened */ 216 217 char* read_buffer; 218 size_t read_buffer_length; /* this much came in */ 219 size_t read_packet_length; /* this much will be returned on read */ 220 spinlock_t read_buffer_lock; 221 int packet_timeout_jiffies; 222 unsigned long read_last_arrival; 223 224 wait_queue_head_t read_wait; 225 wait_queue_head_t write_wait; 226 227 char* interrupt_in_buffer; 228 struct usb_endpoint_descriptor* interrupt_in_endpoint; 229 struct urb* interrupt_in_urb; 230 int interrupt_in_interval; 231 int interrupt_in_running; 232 int interrupt_in_done; 233 234 char* interrupt_out_buffer; 235 struct usb_endpoint_descriptor* interrupt_out_endpoint; 236 struct urb* interrupt_out_urb; 237 int interrupt_out_interval; 238 int interrupt_out_busy; 239 240 }; 241 242 243 /* local function prototypes */ 244 static ssize_t tower_read (struct file *file, char __user *buffer, size_t count, loff_t *ppos); 245 static ssize_t tower_write (struct file *file, const char __user *buffer, size_t count, loff_t *ppos); 246 static inline void tower_delete (struct lego_usb_tower *dev); 247 static int tower_open (struct inode *inode, struct file *file); 248 static int tower_release (struct inode *inode, struct file *file); 249 static unsigned int tower_poll (struct file *file, poll_table *wait); 250 static loff_t tower_llseek (struct file *file, loff_t off, int whence); 251 252 static void tower_abort_transfers (struct lego_usb_tower *dev); 253 static void tower_check_for_read_packet (struct lego_usb_tower *dev); 254 static void tower_interrupt_in_callback (struct urb *urb); 255 static void tower_interrupt_out_callback (struct urb *urb); 256 257 static int tower_probe (struct usb_interface *interface, const struct usb_device_id *id); 258 static void tower_disconnect (struct usb_interface *interface); 259 260 261 /* file operations needed when we register this driver */ 262 static const struct file_operations tower_fops = { 263 .owner = THIS_MODULE, 264 .read = tower_read, 265 .write = tower_write, 266 .open = tower_open, 267 .release = tower_release, 268 .poll = tower_poll, 269 .llseek = tower_llseek, 270 }; 271 272 static char *legousbtower_devnode(struct device *dev, umode_t *mode) 273 { 274 return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev)); 275 } 276 277 /* 278 * usb class driver info in order to get a minor number from the usb core, 279 * and to have the device registered with the driver core 280 */ 281 static struct usb_class_driver tower_class = { 282 .name = "legousbtower%d", 283 .devnode = legousbtower_devnode, 284 .fops = &tower_fops, 285 .minor_base = LEGO_USB_TOWER_MINOR_BASE, 286 }; 287 288 289 /* usb specific object needed to register this driver with the usb subsystem */ 290 static struct usb_driver tower_driver = { 291 .name = "legousbtower", 292 .probe = tower_probe, 293 .disconnect = tower_disconnect, 294 .id_table = tower_table, 295 }; 296 297 298 /** 299 * lego_usb_tower_debug_data 300 */ 301 static inline void lego_usb_tower_debug_data (int level, const char *function, int size, const unsigned char *data) 302 { 303 int i; 304 305 if (debug < level) 306 return; 307 308 printk (KERN_DEBUG "%s: %s - length = %d, data = ", __FILE__, function, size); 309 for (i = 0; i < size; ++i) { 310 printk ("%.2x ", data[i]); 311 } 312 printk ("\n"); 313 } 314 315 316 /** 317 * tower_delete 318 */ 319 static inline void tower_delete (struct lego_usb_tower *dev) 320 { 321 tower_abort_transfers (dev); 322 323 /* free data structures */ 324 usb_free_urb(dev->interrupt_in_urb); 325 usb_free_urb(dev->interrupt_out_urb); 326 kfree (dev->read_buffer); 327 kfree (dev->interrupt_in_buffer); 328 kfree (dev->interrupt_out_buffer); 329 kfree (dev); 330 } 331 332 333 /** 334 * tower_open 335 */ 336 static int tower_open (struct inode *inode, struct file *file) 337 { 338 struct lego_usb_tower *dev = NULL; 339 int subminor; 340 int retval = 0; 341 struct usb_interface *interface; 342 struct tower_reset_reply reset_reply; 343 int result; 344 345 nonseekable_open(inode, file); 346 subminor = iminor(inode); 347 348 interface = usb_find_interface (&tower_driver, subminor); 349 350 if (!interface) { 351 printk(KERN_ERR "%s - error, can't find device for minor %d\n", 352 __func__, subminor); 353 retval = -ENODEV; 354 goto exit; 355 } 356 357 mutex_lock(&open_disc_mutex); 358 dev = usb_get_intfdata(interface); 359 360 if (!dev) { 361 mutex_unlock(&open_disc_mutex); 362 retval = -ENODEV; 363 goto exit; 364 } 365 366 /* lock this device */ 367 if (mutex_lock_interruptible(&dev->lock)) { 368 mutex_unlock(&open_disc_mutex); 369 retval = -ERESTARTSYS; 370 goto exit; 371 } 372 373 374 /* allow opening only once */ 375 if (dev->open_count) { 376 mutex_unlock(&open_disc_mutex); 377 retval = -EBUSY; 378 goto unlock_exit; 379 } 380 dev->open_count = 1; 381 mutex_unlock(&open_disc_mutex); 382 383 /* reset the tower */ 384 result = usb_control_msg (dev->udev, 385 usb_rcvctrlpipe(dev->udev, 0), 386 LEGO_USB_TOWER_REQUEST_RESET, 387 USB_TYPE_VENDOR | USB_DIR_IN | USB_RECIP_DEVICE, 388 0, 389 0, 390 &reset_reply, 391 sizeof(reset_reply), 392 1000); 393 if (result < 0) { 394 dev_err(&dev->udev->dev, 395 "LEGO USB Tower reset control request failed\n"); 396 retval = result; 397 goto unlock_exit; 398 } 399 400 /* initialize in direction */ 401 dev->read_buffer_length = 0; 402 dev->read_packet_length = 0; 403 usb_fill_int_urb (dev->interrupt_in_urb, 404 dev->udev, 405 usb_rcvintpipe(dev->udev, dev->interrupt_in_endpoint->bEndpointAddress), 406 dev->interrupt_in_buffer, 407 usb_endpoint_maxp(dev->interrupt_in_endpoint), 408 tower_interrupt_in_callback, 409 dev, 410 dev->interrupt_in_interval); 411 412 dev->interrupt_in_running = 1; 413 dev->interrupt_in_done = 0; 414 mb(); 415 416 retval = usb_submit_urb (dev->interrupt_in_urb, GFP_KERNEL); 417 if (retval) { 418 dev_err(&dev->udev->dev, 419 "Couldn't submit interrupt_in_urb %d\n", retval); 420 dev->interrupt_in_running = 0; 421 dev->open_count = 0; 422 goto unlock_exit; 423 } 424 425 /* save device in the file's private structure */ 426 file->private_data = dev; 427 428 unlock_exit: 429 mutex_unlock(&dev->lock); 430 431 exit: 432 return retval; 433 } 434 435 /** 436 * tower_release 437 */ 438 static int tower_release (struct inode *inode, struct file *file) 439 { 440 struct lego_usb_tower *dev; 441 int retval = 0; 442 443 dev = file->private_data; 444 445 if (dev == NULL) { 446 dbg(1, "%s: object is NULL", __func__); 447 retval = -ENODEV; 448 goto exit_nolock; 449 } 450 451 mutex_lock(&open_disc_mutex); 452 if (mutex_lock_interruptible(&dev->lock)) { 453 retval = -ERESTARTSYS; 454 goto exit; 455 } 456 457 if (dev->open_count != 1) { 458 dbg(1, "%s: device not opened exactly once", __func__); 459 retval = -ENODEV; 460 goto unlock_exit; 461 } 462 if (dev->udev == NULL) { 463 /* the device was unplugged before the file was released */ 464 465 /* unlock here as tower_delete frees dev */ 466 mutex_unlock(&dev->lock); 467 tower_delete (dev); 468 goto exit; 469 } 470 471 /* wait until write transfer is finished */ 472 if (dev->interrupt_out_busy) { 473 wait_event_interruptible_timeout (dev->write_wait, !dev->interrupt_out_busy, 2 * HZ); 474 } 475 tower_abort_transfers (dev); 476 dev->open_count = 0; 477 478 unlock_exit: 479 mutex_unlock(&dev->lock); 480 481 exit: 482 mutex_unlock(&open_disc_mutex); 483 exit_nolock: 484 return retval; 485 } 486 487 488 /** 489 * tower_abort_transfers 490 * aborts transfers and frees associated data structures 491 */ 492 static void tower_abort_transfers (struct lego_usb_tower *dev) 493 { 494 if (dev == NULL) { 495 dbg(1, "%s: dev is null", __func__); 496 return; 497 } 498 499 /* shutdown transfer */ 500 if (dev->interrupt_in_running) { 501 dev->interrupt_in_running = 0; 502 mb(); 503 if (dev->udev) 504 usb_kill_urb (dev->interrupt_in_urb); 505 } 506 if (dev->interrupt_out_busy && dev->udev) 507 usb_kill_urb(dev->interrupt_out_urb); 508 } 509 510 511 /** 512 * tower_check_for_read_packet 513 * 514 * To get correct semantics for signals and non-blocking I/O 515 * with packetizing we pretend not to see any data in the read buffer 516 * until it has been there unchanged for at least 517 * dev->packet_timeout_jiffies, or until the buffer is full. 518 */ 519 static void tower_check_for_read_packet (struct lego_usb_tower *dev) 520 { 521 spin_lock_irq (&dev->read_buffer_lock); 522 if (!packet_timeout 523 || time_after(jiffies, dev->read_last_arrival + dev->packet_timeout_jiffies) 524 || dev->read_buffer_length == read_buffer_size) { 525 dev->read_packet_length = dev->read_buffer_length; 526 } 527 dev->interrupt_in_done = 0; 528 spin_unlock_irq (&dev->read_buffer_lock); 529 } 530 531 532 /** 533 * tower_poll 534 */ 535 static unsigned int tower_poll (struct file *file, poll_table *wait) 536 { 537 struct lego_usb_tower *dev; 538 unsigned int mask = 0; 539 540 dev = file->private_data; 541 542 if (!dev->udev) 543 return POLLERR | POLLHUP; 544 545 poll_wait(file, &dev->read_wait, wait); 546 poll_wait(file, &dev->write_wait, wait); 547 548 tower_check_for_read_packet(dev); 549 if (dev->read_packet_length > 0) { 550 mask |= POLLIN | POLLRDNORM; 551 } 552 if (!dev->interrupt_out_busy) { 553 mask |= POLLOUT | POLLWRNORM; 554 } 555 556 return mask; 557 } 558 559 560 /** 561 * tower_llseek 562 */ 563 static loff_t tower_llseek (struct file *file, loff_t off, int whence) 564 { 565 return -ESPIPE; /* unseekable */ 566 } 567 568 569 /** 570 * tower_read 571 */ 572 static ssize_t tower_read (struct file *file, char __user *buffer, size_t count, loff_t *ppos) 573 { 574 struct lego_usb_tower *dev; 575 size_t bytes_to_read; 576 int i; 577 int retval = 0; 578 unsigned long timeout = 0; 579 580 dev = file->private_data; 581 582 /* lock this object */ 583 if (mutex_lock_interruptible(&dev->lock)) { 584 retval = -ERESTARTSYS; 585 goto exit; 586 } 587 588 /* verify that the device wasn't unplugged */ 589 if (dev->udev == NULL) { 590 retval = -ENODEV; 591 printk(KERN_ERR "legousbtower: No device or device unplugged %d\n", retval); 592 goto unlock_exit; 593 } 594 595 /* verify that we actually have some data to read */ 596 if (count == 0) { 597 dbg(1, "%s: read request of 0 bytes", __func__); 598 goto unlock_exit; 599 } 600 601 if (read_timeout) { 602 timeout = jiffies + read_timeout * HZ / 1000; 603 } 604 605 /* wait for data */ 606 tower_check_for_read_packet (dev); 607 while (dev->read_packet_length == 0) { 608 if (file->f_flags & O_NONBLOCK) { 609 retval = -EAGAIN; 610 goto unlock_exit; 611 } 612 retval = wait_event_interruptible_timeout(dev->read_wait, dev->interrupt_in_done, dev->packet_timeout_jiffies); 613 if (retval < 0) { 614 goto unlock_exit; 615 } 616 617 /* reset read timeout during read or write activity */ 618 if (read_timeout 619 && (dev->read_buffer_length || dev->interrupt_out_busy)) { 620 timeout = jiffies + read_timeout * HZ / 1000; 621 } 622 /* check for read timeout */ 623 if (read_timeout && time_after (jiffies, timeout)) { 624 retval = -ETIMEDOUT; 625 goto unlock_exit; 626 } 627 tower_check_for_read_packet (dev); 628 } 629 630 /* copy the data from read_buffer into userspace */ 631 bytes_to_read = min(count, dev->read_packet_length); 632 633 if (copy_to_user (buffer, dev->read_buffer, bytes_to_read)) { 634 retval = -EFAULT; 635 goto unlock_exit; 636 } 637 638 spin_lock_irq (&dev->read_buffer_lock); 639 dev->read_buffer_length -= bytes_to_read; 640 dev->read_packet_length -= bytes_to_read; 641 for (i=0; i<dev->read_buffer_length; i++) { 642 dev->read_buffer[i] = dev->read_buffer[i+bytes_to_read]; 643 } 644 spin_unlock_irq (&dev->read_buffer_lock); 645 646 retval = bytes_to_read; 647 648 unlock_exit: 649 /* unlock the device */ 650 mutex_unlock(&dev->lock); 651 652 exit: 653 return retval; 654 } 655 656 657 /** 658 * tower_write 659 */ 660 static ssize_t tower_write (struct file *file, const char __user *buffer, size_t count, loff_t *ppos) 661 { 662 struct lego_usb_tower *dev; 663 size_t bytes_to_write; 664 int retval = 0; 665 666 dev = file->private_data; 667 668 /* lock this object */ 669 if (mutex_lock_interruptible(&dev->lock)) { 670 retval = -ERESTARTSYS; 671 goto exit; 672 } 673 674 /* verify that the device wasn't unplugged */ 675 if (dev->udev == NULL) { 676 retval = -ENODEV; 677 printk(KERN_ERR "legousbtower: No device or device unplugged %d\n", retval); 678 goto unlock_exit; 679 } 680 681 /* verify that we actually have some data to write */ 682 if (count == 0) { 683 dbg(1, "%s: write request of 0 bytes", __func__); 684 goto unlock_exit; 685 } 686 687 /* wait until previous transfer is finished */ 688 while (dev->interrupt_out_busy) { 689 if (file->f_flags & O_NONBLOCK) { 690 retval = -EAGAIN; 691 goto unlock_exit; 692 } 693 retval = wait_event_interruptible (dev->write_wait, !dev->interrupt_out_busy); 694 if (retval) { 695 goto unlock_exit; 696 } 697 } 698 699 /* write the data into interrupt_out_buffer from userspace */ 700 bytes_to_write = min_t(int, count, write_buffer_size); 701 dbg(4, "%s: count = %Zd, bytes_to_write = %Zd", __func__, count, bytes_to_write); 702 703 if (copy_from_user (dev->interrupt_out_buffer, buffer, bytes_to_write)) { 704 retval = -EFAULT; 705 goto unlock_exit; 706 } 707 708 /* send off the urb */ 709 usb_fill_int_urb(dev->interrupt_out_urb, 710 dev->udev, 711 usb_sndintpipe(dev->udev, dev->interrupt_out_endpoint->bEndpointAddress), 712 dev->interrupt_out_buffer, 713 bytes_to_write, 714 tower_interrupt_out_callback, 715 dev, 716 dev->interrupt_out_interval); 717 718 dev->interrupt_out_busy = 1; 719 wmb(); 720 721 retval = usb_submit_urb (dev->interrupt_out_urb, GFP_KERNEL); 722 if (retval) { 723 dev->interrupt_out_busy = 0; 724 dev_err(&dev->udev->dev, 725 "Couldn't submit interrupt_out_urb %d\n", retval); 726 goto unlock_exit; 727 } 728 retval = bytes_to_write; 729 730 unlock_exit: 731 /* unlock the device */ 732 mutex_unlock(&dev->lock); 733 734 exit: 735 return retval; 736 } 737 738 739 /** 740 * tower_interrupt_in_callback 741 */ 742 static void tower_interrupt_in_callback (struct urb *urb) 743 { 744 struct lego_usb_tower *dev = urb->context; 745 int status = urb->status; 746 int retval; 747 748 lego_usb_tower_debug_data(5, __func__, urb->actual_length, urb->transfer_buffer); 749 750 if (status) { 751 if (status == -ENOENT || 752 status == -ECONNRESET || 753 status == -ESHUTDOWN) { 754 goto exit; 755 } else { 756 dbg(1, "%s: nonzero status received: %d", __func__, status); 757 goto resubmit; /* maybe we can recover */ 758 } 759 } 760 761 if (urb->actual_length > 0) { 762 spin_lock (&dev->read_buffer_lock); 763 if (dev->read_buffer_length + urb->actual_length < read_buffer_size) { 764 memcpy (dev->read_buffer + dev->read_buffer_length, 765 dev->interrupt_in_buffer, 766 urb->actual_length); 767 dev->read_buffer_length += urb->actual_length; 768 dev->read_last_arrival = jiffies; 769 dbg(3, "%s: received %d bytes", __func__, urb->actual_length); 770 } else { 771 printk(KERN_WARNING "%s: read_buffer overflow, %d bytes dropped", __func__, urb->actual_length); 772 } 773 spin_unlock (&dev->read_buffer_lock); 774 } 775 776 resubmit: 777 /* resubmit if we're still running */ 778 if (dev->interrupt_in_running && dev->udev) { 779 retval = usb_submit_urb (dev->interrupt_in_urb, GFP_ATOMIC); 780 if (retval) 781 dev_err(&dev->udev->dev, 782 "%s: usb_submit_urb failed (%d)\n", 783 __func__, retval); 784 } 785 786 exit: 787 dev->interrupt_in_done = 1; 788 wake_up_interruptible (&dev->read_wait); 789 790 lego_usb_tower_debug_data(5, __func__, urb->actual_length, urb->transfer_buffer); 791 } 792 793 794 /** 795 * tower_interrupt_out_callback 796 */ 797 static void tower_interrupt_out_callback (struct urb *urb) 798 { 799 struct lego_usb_tower *dev = urb->context; 800 int status = urb->status; 801 802 lego_usb_tower_debug_data(5, __func__, urb->actual_length, urb->transfer_buffer); 803 804 /* sync/async unlink faults aren't errors */ 805 if (status && !(status == -ENOENT || 806 status == -ECONNRESET || 807 status == -ESHUTDOWN)) { 808 dbg(1, "%s - nonzero write bulk status received: %d", 809 __func__, status); 810 } 811 812 dev->interrupt_out_busy = 0; 813 wake_up_interruptible(&dev->write_wait); 814 815 lego_usb_tower_debug_data(5, __func__, urb->actual_length, urb->transfer_buffer); 816 } 817 818 819 /** 820 * tower_probe 821 * 822 * Called by the usb core when a new device is connected that it thinks 823 * this driver might be interested in. 824 */ 825 static int tower_probe (struct usb_interface *interface, const struct usb_device_id *id) 826 { 827 struct device *idev = &interface->dev; 828 struct usb_device *udev = interface_to_usbdev(interface); 829 struct lego_usb_tower *dev = NULL; 830 struct usb_host_interface *iface_desc; 831 struct usb_endpoint_descriptor* endpoint; 832 struct tower_get_version_reply get_version_reply; 833 int i; 834 int retval = -ENOMEM; 835 int result; 836 837 /* allocate memory for our device state and initialize it */ 838 839 dev = kmalloc (sizeof(struct lego_usb_tower), GFP_KERNEL); 840 841 if (dev == NULL) { 842 dev_err(idev, "Out of memory\n"); 843 goto exit; 844 } 845 846 mutex_init(&dev->lock); 847 848 dev->udev = udev; 849 dev->open_count = 0; 850 851 dev->read_buffer = NULL; 852 dev->read_buffer_length = 0; 853 dev->read_packet_length = 0; 854 spin_lock_init (&dev->read_buffer_lock); 855 dev->packet_timeout_jiffies = packet_timeout * HZ / 1000; 856 dev->read_last_arrival = jiffies; 857 858 init_waitqueue_head (&dev->read_wait); 859 init_waitqueue_head (&dev->write_wait); 860 861 dev->interrupt_in_buffer = NULL; 862 dev->interrupt_in_endpoint = NULL; 863 dev->interrupt_in_urb = NULL; 864 dev->interrupt_in_running = 0; 865 dev->interrupt_in_done = 0; 866 867 dev->interrupt_out_buffer = NULL; 868 dev->interrupt_out_endpoint = NULL; 869 dev->interrupt_out_urb = NULL; 870 dev->interrupt_out_busy = 0; 871 872 iface_desc = interface->cur_altsetting; 873 874 /* set up the endpoint information */ 875 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) { 876 endpoint = &iface_desc->endpoint[i].desc; 877 878 if (usb_endpoint_xfer_int(endpoint)) { 879 if (usb_endpoint_dir_in(endpoint)) 880 dev->interrupt_in_endpoint = endpoint; 881 else 882 dev->interrupt_out_endpoint = endpoint; 883 } 884 } 885 if(dev->interrupt_in_endpoint == NULL) { 886 dev_err(idev, "interrupt in endpoint not found\n"); 887 goto error; 888 } 889 if (dev->interrupt_out_endpoint == NULL) { 890 dev_err(idev, "interrupt out endpoint not found\n"); 891 goto error; 892 } 893 894 dev->read_buffer = kmalloc (read_buffer_size, GFP_KERNEL); 895 if (!dev->read_buffer) { 896 dev_err(idev, "Couldn't allocate read_buffer\n"); 897 goto error; 898 } 899 dev->interrupt_in_buffer = kmalloc (usb_endpoint_maxp(dev->interrupt_in_endpoint), GFP_KERNEL); 900 if (!dev->interrupt_in_buffer) { 901 dev_err(idev, "Couldn't allocate interrupt_in_buffer\n"); 902 goto error; 903 } 904 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL); 905 if (!dev->interrupt_in_urb) { 906 dev_err(idev, "Couldn't allocate interrupt_in_urb\n"); 907 goto error; 908 } 909 dev->interrupt_out_buffer = kmalloc (write_buffer_size, GFP_KERNEL); 910 if (!dev->interrupt_out_buffer) { 911 dev_err(idev, "Couldn't allocate interrupt_out_buffer\n"); 912 goto error; 913 } 914 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL); 915 if (!dev->interrupt_out_urb) { 916 dev_err(idev, "Couldn't allocate interrupt_out_urb\n"); 917 goto error; 918 } 919 dev->interrupt_in_interval = interrupt_in_interval ? interrupt_in_interval : dev->interrupt_in_endpoint->bInterval; 920 dev->interrupt_out_interval = interrupt_out_interval ? interrupt_out_interval : dev->interrupt_out_endpoint->bInterval; 921 922 /* we can register the device now, as it is ready */ 923 usb_set_intfdata (interface, dev); 924 925 retval = usb_register_dev (interface, &tower_class); 926 927 if (retval) { 928 /* something prevented us from registering this driver */ 929 dev_err(idev, "Not able to get a minor for this device.\n"); 930 usb_set_intfdata (interface, NULL); 931 goto error; 932 } 933 dev->minor = interface->minor; 934 935 /* let the user know what node this device is now attached to */ 936 dev_info(&interface->dev, "LEGO USB Tower #%d now attached to major " 937 "%d minor %d\n", (dev->minor - LEGO_USB_TOWER_MINOR_BASE), 938 USB_MAJOR, dev->minor); 939 940 /* get the firmware version and log it */ 941 result = usb_control_msg (udev, 942 usb_rcvctrlpipe(udev, 0), 943 LEGO_USB_TOWER_REQUEST_GET_VERSION, 944 USB_TYPE_VENDOR | USB_DIR_IN | USB_RECIP_DEVICE, 945 0, 946 0, 947 &get_version_reply, 948 sizeof(get_version_reply), 949 1000); 950 if (result < 0) { 951 dev_err(idev, "LEGO USB Tower get version control request failed\n"); 952 retval = result; 953 goto error; 954 } 955 dev_info(&interface->dev, "LEGO USB Tower firmware version is %d.%d " 956 "build %d\n", get_version_reply.major, 957 get_version_reply.minor, 958 le16_to_cpu(get_version_reply.build_no)); 959 960 961 exit: 962 return retval; 963 964 error: 965 tower_delete(dev); 966 return retval; 967 } 968 969 970 /** 971 * tower_disconnect 972 * 973 * Called by the usb core when the device is removed from the system. 974 */ 975 static void tower_disconnect (struct usb_interface *interface) 976 { 977 struct lego_usb_tower *dev; 978 int minor; 979 980 dev = usb_get_intfdata (interface); 981 mutex_lock(&open_disc_mutex); 982 usb_set_intfdata (interface, NULL); 983 984 minor = dev->minor; 985 986 /* give back our minor */ 987 usb_deregister_dev (interface, &tower_class); 988 989 mutex_lock(&dev->lock); 990 mutex_unlock(&open_disc_mutex); 991 992 /* if the device is not opened, then we clean up right now */ 993 if (!dev->open_count) { 994 mutex_unlock(&dev->lock); 995 tower_delete (dev); 996 } else { 997 dev->udev = NULL; 998 /* wake up pollers */ 999 wake_up_interruptible_all(&dev->read_wait); 1000 wake_up_interruptible_all(&dev->write_wait); 1001 mutex_unlock(&dev->lock); 1002 } 1003 1004 dev_info(&interface->dev, "LEGO USB Tower #%d now disconnected\n", 1005 (minor - LEGO_USB_TOWER_MINOR_BASE)); 1006 } 1007 1008 module_usb_driver(tower_driver); 1009 1010 MODULE_AUTHOR(DRIVER_AUTHOR); 1011 MODULE_DESCRIPTION(DRIVER_DESC); 1012 #ifdef MODULE_LICENSE 1013 MODULE_LICENSE("GPL"); 1014 #endif 1015