1 /** 2 * Generic USB driver for report based interrupt in/out devices 3 * like LD Didactic's USB devices. LD Didactic's USB devices are 4 * HID devices which do not use HID report definitons (they use 5 * raw interrupt in and our reports only for communication). 6 * 7 * This driver uses a ring buffer for time critical reading of 8 * interrupt in reports and provides read and write methods for 9 * raw interrupt reports (similar to the Windows HID driver). 10 * Devices based on the book USB COMPLETE by Jan Axelson may need 11 * such a compatibility to the Windows HID driver. 12 * 13 * Copyright (C) 2005 Michael Hund <mhund@ld-didactic.de> 14 * 15 * This program is free software; you can redistribute it and/or 16 * modify it under the terms of the GNU General Public License as 17 * published by the Free Software Foundation; either version 2 of 18 * the License, or (at your option) any later version. 19 * 20 * Derived from Lego USB Tower driver 21 * Copyright (C) 2003 David Glance <advidgsf@sourceforge.net> 22 * 2001-2004 Juergen Stuber <starblue@users.sourceforge.net> 23 */ 24 25 #include <linux/kernel.h> 26 #include <linux/errno.h> 27 #include <linux/slab.h> 28 #include <linux/module.h> 29 #include <linux/mutex.h> 30 31 #include <linux/uaccess.h> 32 #include <linux/input.h> 33 #include <linux/usb.h> 34 #include <linux/poll.h> 35 36 /* Define these values to match your devices */ 37 #define USB_VENDOR_ID_LD 0x0f11 /* USB Vendor ID of LD Didactic GmbH */ 38 #define USB_DEVICE_ID_LD_CASSY 0x1000 /* USB Product ID of CASSY-S modules with 8 bytes endpoint size */ 39 #define USB_DEVICE_ID_LD_CASSY2 0x1001 /* USB Product ID of CASSY-S modules with 64 bytes endpoint size */ 40 #define USB_DEVICE_ID_LD_POCKETCASSY 0x1010 /* USB Product ID of Pocket-CASSY */ 41 #define USB_DEVICE_ID_LD_POCKETCASSY2 0x1011 /* USB Product ID of Pocket-CASSY 2 (reserved) */ 42 #define USB_DEVICE_ID_LD_MOBILECASSY 0x1020 /* USB Product ID of Mobile-CASSY */ 43 #define USB_DEVICE_ID_LD_MOBILECASSY2 0x1021 /* USB Product ID of Mobile-CASSY 2 (reserved) */ 44 #define USB_DEVICE_ID_LD_MICROCASSYVOLTAGE 0x1031 /* USB Product ID of Micro-CASSY Voltage */ 45 #define USB_DEVICE_ID_LD_MICROCASSYCURRENT 0x1032 /* USB Product ID of Micro-CASSY Current */ 46 #define USB_DEVICE_ID_LD_MICROCASSYTIME 0x1033 /* USB Product ID of Micro-CASSY Time (reserved) */ 47 #define USB_DEVICE_ID_LD_MICROCASSYTEMPERATURE 0x1035 /* USB Product ID of Micro-CASSY Temperature */ 48 #define USB_DEVICE_ID_LD_MICROCASSYPH 0x1038 /* USB Product ID of Micro-CASSY pH */ 49 #define USB_DEVICE_ID_LD_JWM 0x1080 /* USB Product ID of Joule and Wattmeter */ 50 #define USB_DEVICE_ID_LD_DMMP 0x1081 /* USB Product ID of Digital Multimeter P (reserved) */ 51 #define USB_DEVICE_ID_LD_UMIP 0x1090 /* USB Product ID of UMI P */ 52 #define USB_DEVICE_ID_LD_UMIC 0x10A0 /* USB Product ID of UMI C */ 53 #define USB_DEVICE_ID_LD_UMIB 0x10B0 /* USB Product ID of UMI B */ 54 #define USB_DEVICE_ID_LD_XRAY 0x1100 /* USB Product ID of X-Ray Apparatus 55481 */ 55 #define USB_DEVICE_ID_LD_XRAY2 0x1101 /* USB Product ID of X-Ray Apparatus 554800 */ 56 #define USB_DEVICE_ID_LD_XRAYCT 0x1110 /* USB Product ID of X-Ray Apparatus CT 554821*/ 57 #define USB_DEVICE_ID_LD_VIDEOCOM 0x1200 /* USB Product ID of VideoCom */ 58 #define USB_DEVICE_ID_LD_MOTOR 0x1210 /* USB Product ID of Motor (reserved) */ 59 #define USB_DEVICE_ID_LD_COM3LAB 0x2000 /* USB Product ID of COM3LAB */ 60 #define USB_DEVICE_ID_LD_TELEPORT 0x2010 /* USB Product ID of Terminal Adapter */ 61 #define USB_DEVICE_ID_LD_NETWORKANALYSER 0x2020 /* USB Product ID of Network Analyser */ 62 #define USB_DEVICE_ID_LD_POWERCONTROL 0x2030 /* USB Product ID of Converter Control Unit */ 63 #define USB_DEVICE_ID_LD_MACHINETEST 0x2040 /* USB Product ID of Machine Test System */ 64 #define USB_DEVICE_ID_LD_MOSTANALYSER 0x2050 /* USB Product ID of MOST Protocol Analyser */ 65 #define USB_DEVICE_ID_LD_MOSTANALYSER2 0x2051 /* USB Product ID of MOST Protocol Analyser 2 */ 66 #define USB_DEVICE_ID_LD_ABSESP 0x2060 /* USB Product ID of ABS ESP */ 67 #define USB_DEVICE_ID_LD_AUTODATABUS 0x2070 /* USB Product ID of Automotive Data Buses */ 68 #define USB_DEVICE_ID_LD_MCT 0x2080 /* USB Product ID of Microcontroller technique */ 69 #define USB_DEVICE_ID_LD_HYBRID 0x2090 /* USB Product ID of Automotive Hybrid */ 70 #define USB_DEVICE_ID_LD_HEATCONTROL 0x20A0 /* USB Product ID of Heat control */ 71 72 #ifdef CONFIG_USB_DYNAMIC_MINORS 73 #define USB_LD_MINOR_BASE 0 74 #else 75 #define USB_LD_MINOR_BASE 176 76 #endif 77 78 /* table of devices that work with this driver */ 79 static const struct usb_device_id ld_usb_table[] = { 80 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY) }, 81 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY2) }, 82 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY) }, 83 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY2) }, 84 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY) }, 85 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY2) }, 86 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYVOLTAGE) }, 87 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYCURRENT) }, 88 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYTIME) }, 89 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYTEMPERATURE) }, 90 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYPH) }, 91 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_JWM) }, 92 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_DMMP) }, 93 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIP) }, 94 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIC) }, 95 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIB) }, 96 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY) }, 97 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY2) }, 98 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_VIDEOCOM) }, 99 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOTOR) }, 100 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_COM3LAB) }, 101 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_TELEPORT) }, 102 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_NETWORKANALYSER) }, 103 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POWERCONTROL) }, 104 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MACHINETEST) }, 105 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOSTANALYSER) }, 106 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOSTANALYSER2) }, 107 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_ABSESP) }, 108 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_AUTODATABUS) }, 109 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MCT) }, 110 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_HYBRID) }, 111 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_HEATCONTROL) }, 112 { } /* Terminating entry */ 113 }; 114 MODULE_DEVICE_TABLE(usb, ld_usb_table); 115 MODULE_VERSION("V0.14"); 116 MODULE_AUTHOR("Michael Hund <mhund@ld-didactic.de>"); 117 MODULE_DESCRIPTION("LD USB Driver"); 118 MODULE_LICENSE("GPL"); 119 MODULE_SUPPORTED_DEVICE("LD USB Devices"); 120 121 /* All interrupt in transfers are collected in a ring buffer to 122 * avoid racing conditions and get better performance of the driver. 123 */ 124 static int ring_buffer_size = 128; 125 module_param(ring_buffer_size, int, 0000); 126 MODULE_PARM_DESC(ring_buffer_size, "Read ring buffer size in reports"); 127 128 /* The write_buffer can contain more than one interrupt out transfer. 129 */ 130 static int write_buffer_size = 10; 131 module_param(write_buffer_size, int, 0000); 132 MODULE_PARM_DESC(write_buffer_size, "Write buffer size in reports"); 133 134 /* As of kernel version 2.6.4 ehci-hcd uses an 135 * "only one interrupt transfer per frame" shortcut 136 * to simplify the scheduling of periodic transfers. 137 * This conflicts with our standard 1ms intervals for in and out URBs. 138 * We use default intervals of 2ms for in and 2ms for out transfers, 139 * which should be fast enough. 140 * Increase the interval to allow more devices that do interrupt transfers, 141 * or set to 1 to use the standard interval from the endpoint descriptors. 142 */ 143 static int min_interrupt_in_interval = 2; 144 module_param(min_interrupt_in_interval, int, 0000); 145 MODULE_PARM_DESC(min_interrupt_in_interval, "Minimum interrupt in interval in ms"); 146 147 static int min_interrupt_out_interval = 2; 148 module_param(min_interrupt_out_interval, int, 0000); 149 MODULE_PARM_DESC(min_interrupt_out_interval, "Minimum interrupt out interval in ms"); 150 151 /* Structure to hold all of our device specific stuff */ 152 struct ld_usb { 153 struct mutex mutex; /* locks this structure */ 154 struct usb_interface *intf; /* save off the usb interface pointer */ 155 156 int open_count; /* number of times this port has been opened */ 157 158 char *ring_buffer; 159 unsigned int ring_head; 160 unsigned int ring_tail; 161 162 wait_queue_head_t read_wait; 163 wait_queue_head_t write_wait; 164 165 char *interrupt_in_buffer; 166 struct usb_endpoint_descriptor *interrupt_in_endpoint; 167 struct urb *interrupt_in_urb; 168 int interrupt_in_interval; 169 size_t interrupt_in_endpoint_size; 170 int interrupt_in_running; 171 int interrupt_in_done; 172 int buffer_overflow; 173 spinlock_t rbsl; 174 175 char *interrupt_out_buffer; 176 struct usb_endpoint_descriptor *interrupt_out_endpoint; 177 struct urb *interrupt_out_urb; 178 int interrupt_out_interval; 179 size_t interrupt_out_endpoint_size; 180 int interrupt_out_busy; 181 }; 182 183 static struct usb_driver ld_usb_driver; 184 185 /** 186 * ld_usb_abort_transfers 187 * aborts transfers and frees associated data structures 188 */ 189 static void ld_usb_abort_transfers(struct ld_usb *dev) 190 { 191 /* shutdown transfer */ 192 if (dev->interrupt_in_running) { 193 dev->interrupt_in_running = 0; 194 if (dev->intf) 195 usb_kill_urb(dev->interrupt_in_urb); 196 } 197 if (dev->interrupt_out_busy) 198 if (dev->intf) 199 usb_kill_urb(dev->interrupt_out_urb); 200 } 201 202 /** 203 * ld_usb_delete 204 */ 205 static void ld_usb_delete(struct ld_usb *dev) 206 { 207 ld_usb_abort_transfers(dev); 208 209 /* free data structures */ 210 usb_free_urb(dev->interrupt_in_urb); 211 usb_free_urb(dev->interrupt_out_urb); 212 kfree(dev->ring_buffer); 213 kfree(dev->interrupt_in_buffer); 214 kfree(dev->interrupt_out_buffer); 215 kfree(dev); 216 } 217 218 /** 219 * ld_usb_interrupt_in_callback 220 */ 221 static void ld_usb_interrupt_in_callback(struct urb *urb) 222 { 223 struct ld_usb *dev = urb->context; 224 size_t *actual_buffer; 225 unsigned int next_ring_head; 226 int status = urb->status; 227 int retval; 228 229 if (status) { 230 if (status == -ENOENT || 231 status == -ECONNRESET || 232 status == -ESHUTDOWN) { 233 goto exit; 234 } else { 235 dev_dbg(&dev->intf->dev, 236 "%s: nonzero status received: %d\n", __func__, 237 status); 238 spin_lock(&dev->rbsl); 239 goto resubmit; /* maybe we can recover */ 240 } 241 } 242 243 spin_lock(&dev->rbsl); 244 if (urb->actual_length > 0) { 245 next_ring_head = (dev->ring_head+1) % ring_buffer_size; 246 if (next_ring_head != dev->ring_tail) { 247 actual_buffer = (size_t *)(dev->ring_buffer + dev->ring_head * (sizeof(size_t)+dev->interrupt_in_endpoint_size)); 248 /* actual_buffer gets urb->actual_length + interrupt_in_buffer */ 249 *actual_buffer = urb->actual_length; 250 memcpy(actual_buffer+1, dev->interrupt_in_buffer, urb->actual_length); 251 dev->ring_head = next_ring_head; 252 dev_dbg(&dev->intf->dev, "%s: received %d bytes\n", 253 __func__, urb->actual_length); 254 } else { 255 dev_warn(&dev->intf->dev, 256 "Ring buffer overflow, %d bytes dropped\n", 257 urb->actual_length); 258 dev->buffer_overflow = 1; 259 } 260 } 261 262 resubmit: 263 /* resubmit if we're still running */ 264 if (dev->interrupt_in_running && !dev->buffer_overflow && dev->intf) { 265 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC); 266 if (retval) { 267 dev_err(&dev->intf->dev, 268 "usb_submit_urb failed (%d)\n", retval); 269 dev->buffer_overflow = 1; 270 } 271 } 272 spin_unlock(&dev->rbsl); 273 exit: 274 dev->interrupt_in_done = 1; 275 wake_up_interruptible(&dev->read_wait); 276 } 277 278 /** 279 * ld_usb_interrupt_out_callback 280 */ 281 static void ld_usb_interrupt_out_callback(struct urb *urb) 282 { 283 struct ld_usb *dev = urb->context; 284 int status = urb->status; 285 286 /* sync/async unlink faults aren't errors */ 287 if (status && !(status == -ENOENT || 288 status == -ECONNRESET || 289 status == -ESHUTDOWN)) 290 dev_dbg(&dev->intf->dev, 291 "%s - nonzero write interrupt status received: %d\n", 292 __func__, status); 293 294 dev->interrupt_out_busy = 0; 295 wake_up_interruptible(&dev->write_wait); 296 } 297 298 /** 299 * ld_usb_open 300 */ 301 static int ld_usb_open(struct inode *inode, struct file *file) 302 { 303 struct ld_usb *dev; 304 int subminor; 305 int retval; 306 struct usb_interface *interface; 307 308 nonseekable_open(inode, file); 309 subminor = iminor(inode); 310 311 interface = usb_find_interface(&ld_usb_driver, subminor); 312 313 if (!interface) { 314 printk(KERN_ERR "%s - error, can't find device for minor %d\n", 315 __func__, subminor); 316 return -ENODEV; 317 } 318 319 dev = usb_get_intfdata(interface); 320 321 if (!dev) 322 return -ENODEV; 323 324 /* lock this device */ 325 if (mutex_lock_interruptible(&dev->mutex)) 326 return -ERESTARTSYS; 327 328 /* allow opening only once */ 329 if (dev->open_count) { 330 retval = -EBUSY; 331 goto unlock_exit; 332 } 333 dev->open_count = 1; 334 335 /* initialize in direction */ 336 dev->ring_head = 0; 337 dev->ring_tail = 0; 338 dev->buffer_overflow = 0; 339 usb_fill_int_urb(dev->interrupt_in_urb, 340 interface_to_usbdev(interface), 341 usb_rcvintpipe(interface_to_usbdev(interface), 342 dev->interrupt_in_endpoint->bEndpointAddress), 343 dev->interrupt_in_buffer, 344 dev->interrupt_in_endpoint_size, 345 ld_usb_interrupt_in_callback, 346 dev, 347 dev->interrupt_in_interval); 348 349 dev->interrupt_in_running = 1; 350 dev->interrupt_in_done = 0; 351 352 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL); 353 if (retval) { 354 dev_err(&interface->dev, "Couldn't submit interrupt_in_urb %d\n", retval); 355 dev->interrupt_in_running = 0; 356 dev->open_count = 0; 357 goto unlock_exit; 358 } 359 360 /* save device in the file's private structure */ 361 file->private_data = dev; 362 363 unlock_exit: 364 mutex_unlock(&dev->mutex); 365 366 return retval; 367 } 368 369 /** 370 * ld_usb_release 371 */ 372 static int ld_usb_release(struct inode *inode, struct file *file) 373 { 374 struct ld_usb *dev; 375 int retval = 0; 376 377 dev = file->private_data; 378 379 if (dev == NULL) { 380 retval = -ENODEV; 381 goto exit; 382 } 383 384 if (mutex_lock_interruptible(&dev->mutex)) { 385 retval = -ERESTARTSYS; 386 goto exit; 387 } 388 389 if (dev->open_count != 1) { 390 retval = -ENODEV; 391 goto unlock_exit; 392 } 393 if (dev->intf == NULL) { 394 /* the device was unplugged before the file was released */ 395 mutex_unlock(&dev->mutex); 396 /* unlock here as ld_usb_delete frees dev */ 397 ld_usb_delete(dev); 398 goto exit; 399 } 400 401 /* wait until write transfer is finished */ 402 if (dev->interrupt_out_busy) 403 wait_event_interruptible_timeout(dev->write_wait, !dev->interrupt_out_busy, 2 * HZ); 404 ld_usb_abort_transfers(dev); 405 dev->open_count = 0; 406 407 unlock_exit: 408 mutex_unlock(&dev->mutex); 409 410 exit: 411 return retval; 412 } 413 414 /** 415 * ld_usb_poll 416 */ 417 static unsigned int ld_usb_poll(struct file *file, poll_table *wait) 418 { 419 struct ld_usb *dev; 420 unsigned int mask = 0; 421 422 dev = file->private_data; 423 424 if (!dev->intf) 425 return POLLERR | POLLHUP; 426 427 poll_wait(file, &dev->read_wait, wait); 428 poll_wait(file, &dev->write_wait, wait); 429 430 if (dev->ring_head != dev->ring_tail) 431 mask |= POLLIN | POLLRDNORM; 432 if (!dev->interrupt_out_busy) 433 mask |= POLLOUT | POLLWRNORM; 434 435 return mask; 436 } 437 438 /** 439 * ld_usb_read 440 */ 441 static ssize_t ld_usb_read(struct file *file, char __user *buffer, size_t count, 442 loff_t *ppos) 443 { 444 struct ld_usb *dev; 445 size_t *actual_buffer; 446 size_t bytes_to_read; 447 int retval = 0; 448 int rv; 449 450 dev = file->private_data; 451 452 /* verify that we actually have some data to read */ 453 if (count == 0) 454 goto exit; 455 456 /* lock this object */ 457 if (mutex_lock_interruptible(&dev->mutex)) { 458 retval = -ERESTARTSYS; 459 goto exit; 460 } 461 462 /* verify that the device wasn't unplugged */ 463 if (dev->intf == NULL) { 464 retval = -ENODEV; 465 printk(KERN_ERR "ldusb: No device or device unplugged %d\n", retval); 466 goto unlock_exit; 467 } 468 469 /* wait for data */ 470 spin_lock_irq(&dev->rbsl); 471 if (dev->ring_head == dev->ring_tail) { 472 dev->interrupt_in_done = 0; 473 spin_unlock_irq(&dev->rbsl); 474 if (file->f_flags & O_NONBLOCK) { 475 retval = -EAGAIN; 476 goto unlock_exit; 477 } 478 retval = wait_event_interruptible(dev->read_wait, dev->interrupt_in_done); 479 if (retval < 0) 480 goto unlock_exit; 481 } else { 482 spin_unlock_irq(&dev->rbsl); 483 } 484 485 /* actual_buffer contains actual_length + interrupt_in_buffer */ 486 actual_buffer = (size_t *)(dev->ring_buffer + dev->ring_tail * (sizeof(size_t)+dev->interrupt_in_endpoint_size)); 487 bytes_to_read = min(count, *actual_buffer); 488 if (bytes_to_read < *actual_buffer) 489 dev_warn(&dev->intf->dev, "Read buffer overflow, %zd bytes dropped\n", 490 *actual_buffer-bytes_to_read); 491 492 /* copy one interrupt_in_buffer from ring_buffer into userspace */ 493 if (copy_to_user(buffer, actual_buffer+1, bytes_to_read)) { 494 retval = -EFAULT; 495 goto unlock_exit; 496 } 497 dev->ring_tail = (dev->ring_tail+1) % ring_buffer_size; 498 499 retval = bytes_to_read; 500 501 spin_lock_irq(&dev->rbsl); 502 if (dev->buffer_overflow) { 503 dev->buffer_overflow = 0; 504 spin_unlock_irq(&dev->rbsl); 505 rv = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL); 506 if (rv < 0) 507 dev->buffer_overflow = 1; 508 } else { 509 spin_unlock_irq(&dev->rbsl); 510 } 511 512 unlock_exit: 513 /* unlock the device */ 514 mutex_unlock(&dev->mutex); 515 516 exit: 517 return retval; 518 } 519 520 /** 521 * ld_usb_write 522 */ 523 static ssize_t ld_usb_write(struct file *file, const char __user *buffer, 524 size_t count, loff_t *ppos) 525 { 526 struct ld_usb *dev; 527 size_t bytes_to_write; 528 int retval = 0; 529 530 dev = file->private_data; 531 532 /* verify that we actually have some data to write */ 533 if (count == 0) 534 goto exit; 535 536 /* lock this object */ 537 if (mutex_lock_interruptible(&dev->mutex)) { 538 retval = -ERESTARTSYS; 539 goto exit; 540 } 541 542 /* verify that the device wasn't unplugged */ 543 if (dev->intf == NULL) { 544 retval = -ENODEV; 545 printk(KERN_ERR "ldusb: No device or device unplugged %d\n", retval); 546 goto unlock_exit; 547 } 548 549 /* wait until previous transfer is finished */ 550 if (dev->interrupt_out_busy) { 551 if (file->f_flags & O_NONBLOCK) { 552 retval = -EAGAIN; 553 goto unlock_exit; 554 } 555 retval = wait_event_interruptible(dev->write_wait, !dev->interrupt_out_busy); 556 if (retval < 0) { 557 goto unlock_exit; 558 } 559 } 560 561 /* write the data into interrupt_out_buffer from userspace */ 562 bytes_to_write = min(count, write_buffer_size*dev->interrupt_out_endpoint_size); 563 if (bytes_to_write < count) 564 dev_warn(&dev->intf->dev, "Write buffer overflow, %zd bytes dropped\n", count-bytes_to_write); 565 dev_dbg(&dev->intf->dev, "%s: count = %zd, bytes_to_write = %zd\n", 566 __func__, count, bytes_to_write); 567 568 if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) { 569 retval = -EFAULT; 570 goto unlock_exit; 571 } 572 573 if (dev->interrupt_out_endpoint == NULL) { 574 /* try HID_REQ_SET_REPORT=9 on control_endpoint instead of interrupt_out_endpoint */ 575 retval = usb_control_msg(interface_to_usbdev(dev->intf), 576 usb_sndctrlpipe(interface_to_usbdev(dev->intf), 0), 577 9, 578 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT, 579 1 << 8, 0, 580 dev->interrupt_out_buffer, 581 bytes_to_write, 582 USB_CTRL_SET_TIMEOUT * HZ); 583 if (retval < 0) 584 dev_err(&dev->intf->dev, 585 "Couldn't submit HID_REQ_SET_REPORT %d\n", 586 retval); 587 goto unlock_exit; 588 } 589 590 /* send off the urb */ 591 usb_fill_int_urb(dev->interrupt_out_urb, 592 interface_to_usbdev(dev->intf), 593 usb_sndintpipe(interface_to_usbdev(dev->intf), 594 dev->interrupt_out_endpoint->bEndpointAddress), 595 dev->interrupt_out_buffer, 596 bytes_to_write, 597 ld_usb_interrupt_out_callback, 598 dev, 599 dev->interrupt_out_interval); 600 601 dev->interrupt_out_busy = 1; 602 wmb(); 603 604 retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL); 605 if (retval) { 606 dev->interrupt_out_busy = 0; 607 dev_err(&dev->intf->dev, 608 "Couldn't submit interrupt_out_urb %d\n", retval); 609 goto unlock_exit; 610 } 611 retval = bytes_to_write; 612 613 unlock_exit: 614 /* unlock the device */ 615 mutex_unlock(&dev->mutex); 616 617 exit: 618 return retval; 619 } 620 621 /* file operations needed when we register this driver */ 622 static const struct file_operations ld_usb_fops = { 623 .owner = THIS_MODULE, 624 .read = ld_usb_read, 625 .write = ld_usb_write, 626 .open = ld_usb_open, 627 .release = ld_usb_release, 628 .poll = ld_usb_poll, 629 .llseek = no_llseek, 630 }; 631 632 /* 633 * usb class driver info in order to get a minor number from the usb core, 634 * and to have the device registered with the driver core 635 */ 636 static struct usb_class_driver ld_usb_class = { 637 .name = "ldusb%d", 638 .fops = &ld_usb_fops, 639 .minor_base = USB_LD_MINOR_BASE, 640 }; 641 642 /** 643 * ld_usb_probe 644 * 645 * Called by the usb core when a new device is connected that it thinks 646 * this driver might be interested in. 647 */ 648 static int ld_usb_probe(struct usb_interface *intf, const struct usb_device_id *id) 649 { 650 struct usb_device *udev = interface_to_usbdev(intf); 651 struct ld_usb *dev = NULL; 652 struct usb_host_interface *iface_desc; 653 char *buffer; 654 int retval = -ENOMEM; 655 int res; 656 657 /* allocate memory for our device state and initialize it */ 658 659 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 660 if (!dev) 661 goto exit; 662 mutex_init(&dev->mutex); 663 spin_lock_init(&dev->rbsl); 664 dev->intf = intf; 665 init_waitqueue_head(&dev->read_wait); 666 init_waitqueue_head(&dev->write_wait); 667 668 /* workaround for early firmware versions on fast computers */ 669 if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) && 670 ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_CASSY) || 671 (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_COM3LAB)) && 672 (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) { 673 buffer = kmalloc(256, GFP_KERNEL); 674 if (!buffer) 675 goto error; 676 /* usb_string makes SETUP+STALL to leave always ControlReadLoop */ 677 usb_string(udev, 255, buffer, 256); 678 kfree(buffer); 679 } 680 681 iface_desc = intf->cur_altsetting; 682 683 res = usb_find_last_int_in_endpoint(iface_desc, 684 &dev->interrupt_in_endpoint); 685 if (res) { 686 dev_err(&intf->dev, "Interrupt in endpoint not found\n"); 687 retval = res; 688 goto error; 689 } 690 691 res = usb_find_last_int_out_endpoint(iface_desc, 692 &dev->interrupt_out_endpoint); 693 if (res) 694 dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n"); 695 696 dev->interrupt_in_endpoint_size = usb_endpoint_maxp(dev->interrupt_in_endpoint); 697 dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL); 698 if (!dev->ring_buffer) 699 goto error; 700 dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL); 701 if (!dev->interrupt_in_buffer) 702 goto error; 703 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL); 704 if (!dev->interrupt_in_urb) 705 goto error; 706 dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? usb_endpoint_maxp(dev->interrupt_out_endpoint) : 707 udev->descriptor.bMaxPacketSize0; 708 dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL); 709 if (!dev->interrupt_out_buffer) 710 goto error; 711 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL); 712 if (!dev->interrupt_out_urb) 713 goto error; 714 dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval; 715 if (dev->interrupt_out_endpoint) 716 dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval; 717 718 /* we can register the device now, as it is ready */ 719 usb_set_intfdata(intf, dev); 720 721 retval = usb_register_dev(intf, &ld_usb_class); 722 if (retval) { 723 /* something prevented us from registering this driver */ 724 dev_err(&intf->dev, "Not able to get a minor for this device.\n"); 725 usb_set_intfdata(intf, NULL); 726 goto error; 727 } 728 729 /* let the user know what node this device is now attached to */ 730 dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n", 731 (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor); 732 733 exit: 734 return retval; 735 736 error: 737 ld_usb_delete(dev); 738 739 return retval; 740 } 741 742 /** 743 * ld_usb_disconnect 744 * 745 * Called by the usb core when the device is removed from the system. 746 */ 747 static void ld_usb_disconnect(struct usb_interface *intf) 748 { 749 struct ld_usb *dev; 750 int minor; 751 752 dev = usb_get_intfdata(intf); 753 usb_set_intfdata(intf, NULL); 754 755 minor = intf->minor; 756 757 /* give back our minor */ 758 usb_deregister_dev(intf, &ld_usb_class); 759 760 mutex_lock(&dev->mutex); 761 762 /* if the device is not opened, then we clean up right now */ 763 if (!dev->open_count) { 764 mutex_unlock(&dev->mutex); 765 ld_usb_delete(dev); 766 } else { 767 dev->intf = NULL; 768 /* wake up pollers */ 769 wake_up_interruptible_all(&dev->read_wait); 770 wake_up_interruptible_all(&dev->write_wait); 771 mutex_unlock(&dev->mutex); 772 } 773 774 dev_info(&intf->dev, "LD USB Device #%d now disconnected\n", 775 (minor - USB_LD_MINOR_BASE)); 776 } 777 778 /* usb specific object needed to register this driver with the usb subsystem */ 779 static struct usb_driver ld_usb_driver = { 780 .name = "ldusb", 781 .probe = ld_usb_probe, 782 .disconnect = ld_usb_disconnect, 783 .id_table = ld_usb_table, 784 }; 785 786 module_usb_driver(ld_usb_driver); 787 788