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_AUTHOR("Michael Hund <mhund@ld-didactic.de>"); 116 MODULE_DESCRIPTION("LD USB Driver"); 117 MODULE_LICENSE("GPL"); 118 MODULE_SUPPORTED_DEVICE("LD USB Devices"); 119 120 /* All interrupt in transfers are collected in a ring buffer to 121 * avoid racing conditions and get better performance of the driver. 122 */ 123 static int ring_buffer_size = 128; 124 module_param(ring_buffer_size, int, 0000); 125 MODULE_PARM_DESC(ring_buffer_size, "Read ring buffer size in reports"); 126 127 /* The write_buffer can contain more than one interrupt out transfer. 128 */ 129 static int write_buffer_size = 10; 130 module_param(write_buffer_size, int, 0000); 131 MODULE_PARM_DESC(write_buffer_size, "Write buffer size in reports"); 132 133 /* As of kernel version 2.6.4 ehci-hcd uses an 134 * "only one interrupt transfer per frame" shortcut 135 * to simplify the scheduling of periodic transfers. 136 * This conflicts with our standard 1ms intervals for in and out URBs. 137 * We use default intervals of 2ms for in and 2ms for out transfers, 138 * which should be fast enough. 139 * Increase the interval to allow more devices that do interrupt transfers, 140 * or set to 1 to use the standard interval from the endpoint descriptors. 141 */ 142 static int min_interrupt_in_interval = 2; 143 module_param(min_interrupt_in_interval, int, 0000); 144 MODULE_PARM_DESC(min_interrupt_in_interval, "Minimum interrupt in interval in ms"); 145 146 static int min_interrupt_out_interval = 2; 147 module_param(min_interrupt_out_interval, int, 0000); 148 MODULE_PARM_DESC(min_interrupt_out_interval, "Minimum interrupt out interval in ms"); 149 150 /* Structure to hold all of our device specific stuff */ 151 struct ld_usb { 152 struct mutex mutex; /* locks this structure */ 153 struct usb_interface *intf; /* save off the usb interface pointer */ 154 155 int open_count; /* number of times this port has been opened */ 156 157 char *ring_buffer; 158 unsigned int ring_head; 159 unsigned int ring_tail; 160 161 wait_queue_head_t read_wait; 162 wait_queue_head_t write_wait; 163 164 char *interrupt_in_buffer; 165 struct usb_endpoint_descriptor *interrupt_in_endpoint; 166 struct urb *interrupt_in_urb; 167 int interrupt_in_interval; 168 size_t interrupt_in_endpoint_size; 169 int interrupt_in_running; 170 int interrupt_in_done; 171 int buffer_overflow; 172 spinlock_t rbsl; 173 174 char *interrupt_out_buffer; 175 struct usb_endpoint_descriptor *interrupt_out_endpoint; 176 struct urb *interrupt_out_urb; 177 int interrupt_out_interval; 178 size_t interrupt_out_endpoint_size; 179 int interrupt_out_busy; 180 }; 181 182 static struct usb_driver ld_usb_driver; 183 184 /** 185 * ld_usb_abort_transfers 186 * aborts transfers and frees associated data structures 187 */ 188 static void ld_usb_abort_transfers(struct ld_usb *dev) 189 { 190 /* shutdown transfer */ 191 if (dev->interrupt_in_running) { 192 dev->interrupt_in_running = 0; 193 if (dev->intf) 194 usb_kill_urb(dev->interrupt_in_urb); 195 } 196 if (dev->interrupt_out_busy) 197 if (dev->intf) 198 usb_kill_urb(dev->interrupt_out_urb); 199 } 200 201 /** 202 * ld_usb_delete 203 */ 204 static void ld_usb_delete(struct ld_usb *dev) 205 { 206 ld_usb_abort_transfers(dev); 207 208 /* free data structures */ 209 usb_free_urb(dev->interrupt_in_urb); 210 usb_free_urb(dev->interrupt_out_urb); 211 kfree(dev->ring_buffer); 212 kfree(dev->interrupt_in_buffer); 213 kfree(dev->interrupt_out_buffer); 214 kfree(dev); 215 } 216 217 /** 218 * ld_usb_interrupt_in_callback 219 */ 220 static void ld_usb_interrupt_in_callback(struct urb *urb) 221 { 222 struct ld_usb *dev = urb->context; 223 size_t *actual_buffer; 224 unsigned int next_ring_head; 225 int status = urb->status; 226 int retval; 227 228 if (status) { 229 if (status == -ENOENT || 230 status == -ECONNRESET || 231 status == -ESHUTDOWN) { 232 goto exit; 233 } else { 234 dev_dbg(&dev->intf->dev, 235 "%s: nonzero status received: %d\n", __func__, 236 status); 237 spin_lock(&dev->rbsl); 238 goto resubmit; /* maybe we can recover */ 239 } 240 } 241 242 spin_lock(&dev->rbsl); 243 if (urb->actual_length > 0) { 244 next_ring_head = (dev->ring_head+1) % ring_buffer_size; 245 if (next_ring_head != dev->ring_tail) { 246 actual_buffer = (size_t *)(dev->ring_buffer + dev->ring_head * (sizeof(size_t)+dev->interrupt_in_endpoint_size)); 247 /* actual_buffer gets urb->actual_length + interrupt_in_buffer */ 248 *actual_buffer = urb->actual_length; 249 memcpy(actual_buffer+1, dev->interrupt_in_buffer, urb->actual_length); 250 dev->ring_head = next_ring_head; 251 dev_dbg(&dev->intf->dev, "%s: received %d bytes\n", 252 __func__, urb->actual_length); 253 } else { 254 dev_warn(&dev->intf->dev, 255 "Ring buffer overflow, %d bytes dropped\n", 256 urb->actual_length); 257 dev->buffer_overflow = 1; 258 } 259 } 260 261 resubmit: 262 /* resubmit if we're still running */ 263 if (dev->interrupt_in_running && !dev->buffer_overflow && dev->intf) { 264 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC); 265 if (retval) { 266 dev_err(&dev->intf->dev, 267 "usb_submit_urb failed (%d)\n", retval); 268 dev->buffer_overflow = 1; 269 } 270 } 271 spin_unlock(&dev->rbsl); 272 exit: 273 dev->interrupt_in_done = 1; 274 wake_up_interruptible(&dev->read_wait); 275 } 276 277 /** 278 * ld_usb_interrupt_out_callback 279 */ 280 static void ld_usb_interrupt_out_callback(struct urb *urb) 281 { 282 struct ld_usb *dev = urb->context; 283 int status = urb->status; 284 285 /* sync/async unlink faults aren't errors */ 286 if (status && !(status == -ENOENT || 287 status == -ECONNRESET || 288 status == -ESHUTDOWN)) 289 dev_dbg(&dev->intf->dev, 290 "%s - nonzero write interrupt status received: %d\n", 291 __func__, status); 292 293 dev->interrupt_out_busy = 0; 294 wake_up_interruptible(&dev->write_wait); 295 } 296 297 /** 298 * ld_usb_open 299 */ 300 static int ld_usb_open(struct inode *inode, struct file *file) 301 { 302 struct ld_usb *dev; 303 int subminor; 304 int retval; 305 struct usb_interface *interface; 306 307 nonseekable_open(inode, file); 308 subminor = iminor(inode); 309 310 interface = usb_find_interface(&ld_usb_driver, subminor); 311 312 if (!interface) { 313 printk(KERN_ERR "%s - error, can't find device for minor %d\n", 314 __func__, subminor); 315 return -ENODEV; 316 } 317 318 dev = usb_get_intfdata(interface); 319 320 if (!dev) 321 return -ENODEV; 322 323 /* lock this device */ 324 if (mutex_lock_interruptible(&dev->mutex)) 325 return -ERESTARTSYS; 326 327 /* allow opening only once */ 328 if (dev->open_count) { 329 retval = -EBUSY; 330 goto unlock_exit; 331 } 332 dev->open_count = 1; 333 334 /* initialize in direction */ 335 dev->ring_head = 0; 336 dev->ring_tail = 0; 337 dev->buffer_overflow = 0; 338 usb_fill_int_urb(dev->interrupt_in_urb, 339 interface_to_usbdev(interface), 340 usb_rcvintpipe(interface_to_usbdev(interface), 341 dev->interrupt_in_endpoint->bEndpointAddress), 342 dev->interrupt_in_buffer, 343 dev->interrupt_in_endpoint_size, 344 ld_usb_interrupt_in_callback, 345 dev, 346 dev->interrupt_in_interval); 347 348 dev->interrupt_in_running = 1; 349 dev->interrupt_in_done = 0; 350 351 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL); 352 if (retval) { 353 dev_err(&interface->dev, "Couldn't submit interrupt_in_urb %d\n", retval); 354 dev->interrupt_in_running = 0; 355 dev->open_count = 0; 356 goto unlock_exit; 357 } 358 359 /* save device in the file's private structure */ 360 file->private_data = dev; 361 362 unlock_exit: 363 mutex_unlock(&dev->mutex); 364 365 return retval; 366 } 367 368 /** 369 * ld_usb_release 370 */ 371 static int ld_usb_release(struct inode *inode, struct file *file) 372 { 373 struct ld_usb *dev; 374 int retval = 0; 375 376 dev = file->private_data; 377 378 if (dev == NULL) { 379 retval = -ENODEV; 380 goto exit; 381 } 382 383 if (mutex_lock_interruptible(&dev->mutex)) { 384 retval = -ERESTARTSYS; 385 goto exit; 386 } 387 388 if (dev->open_count != 1) { 389 retval = -ENODEV; 390 goto unlock_exit; 391 } 392 if (dev->intf == NULL) { 393 /* the device was unplugged before the file was released */ 394 mutex_unlock(&dev->mutex); 395 /* unlock here as ld_usb_delete frees dev */ 396 ld_usb_delete(dev); 397 goto exit; 398 } 399 400 /* wait until write transfer is finished */ 401 if (dev->interrupt_out_busy) 402 wait_event_interruptible_timeout(dev->write_wait, !dev->interrupt_out_busy, 2 * HZ); 403 ld_usb_abort_transfers(dev); 404 dev->open_count = 0; 405 406 unlock_exit: 407 mutex_unlock(&dev->mutex); 408 409 exit: 410 return retval; 411 } 412 413 /** 414 * ld_usb_poll 415 */ 416 static unsigned int ld_usb_poll(struct file *file, poll_table *wait) 417 { 418 struct ld_usb *dev; 419 unsigned int mask = 0; 420 421 dev = file->private_data; 422 423 if (!dev->intf) 424 return POLLERR | POLLHUP; 425 426 poll_wait(file, &dev->read_wait, wait); 427 poll_wait(file, &dev->write_wait, wait); 428 429 if (dev->ring_head != dev->ring_tail) 430 mask |= POLLIN | POLLRDNORM; 431 if (!dev->interrupt_out_busy) 432 mask |= POLLOUT | POLLWRNORM; 433 434 return mask; 435 } 436 437 /** 438 * ld_usb_read 439 */ 440 static ssize_t ld_usb_read(struct file *file, char __user *buffer, size_t count, 441 loff_t *ppos) 442 { 443 struct ld_usb *dev; 444 size_t *actual_buffer; 445 size_t bytes_to_read; 446 int retval = 0; 447 int rv; 448 449 dev = file->private_data; 450 451 /* verify that we actually have some data to read */ 452 if (count == 0) 453 goto exit; 454 455 /* lock this object */ 456 if (mutex_lock_interruptible(&dev->mutex)) { 457 retval = -ERESTARTSYS; 458 goto exit; 459 } 460 461 /* verify that the device wasn't unplugged */ 462 if (dev->intf == NULL) { 463 retval = -ENODEV; 464 printk(KERN_ERR "ldusb: No device or device unplugged %d\n", retval); 465 goto unlock_exit; 466 } 467 468 /* wait for data */ 469 spin_lock_irq(&dev->rbsl); 470 if (dev->ring_head == dev->ring_tail) { 471 dev->interrupt_in_done = 0; 472 spin_unlock_irq(&dev->rbsl); 473 if (file->f_flags & O_NONBLOCK) { 474 retval = -EAGAIN; 475 goto unlock_exit; 476 } 477 retval = wait_event_interruptible(dev->read_wait, dev->interrupt_in_done); 478 if (retval < 0) 479 goto unlock_exit; 480 } else { 481 spin_unlock_irq(&dev->rbsl); 482 } 483 484 /* actual_buffer contains actual_length + interrupt_in_buffer */ 485 actual_buffer = (size_t *)(dev->ring_buffer + dev->ring_tail * (sizeof(size_t)+dev->interrupt_in_endpoint_size)); 486 bytes_to_read = min(count, *actual_buffer); 487 if (bytes_to_read < *actual_buffer) 488 dev_warn(&dev->intf->dev, "Read buffer overflow, %zd bytes dropped\n", 489 *actual_buffer-bytes_to_read); 490 491 /* copy one interrupt_in_buffer from ring_buffer into userspace */ 492 if (copy_to_user(buffer, actual_buffer+1, bytes_to_read)) { 493 retval = -EFAULT; 494 goto unlock_exit; 495 } 496 dev->ring_tail = (dev->ring_tail+1) % ring_buffer_size; 497 498 retval = bytes_to_read; 499 500 spin_lock_irq(&dev->rbsl); 501 if (dev->buffer_overflow) { 502 dev->buffer_overflow = 0; 503 spin_unlock_irq(&dev->rbsl); 504 rv = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL); 505 if (rv < 0) 506 dev->buffer_overflow = 1; 507 } else { 508 spin_unlock_irq(&dev->rbsl); 509 } 510 511 unlock_exit: 512 /* unlock the device */ 513 mutex_unlock(&dev->mutex); 514 515 exit: 516 return retval; 517 } 518 519 /** 520 * ld_usb_write 521 */ 522 static ssize_t ld_usb_write(struct file *file, const char __user *buffer, 523 size_t count, loff_t *ppos) 524 { 525 struct ld_usb *dev; 526 size_t bytes_to_write; 527 int retval = 0; 528 529 dev = file->private_data; 530 531 /* verify that we actually have some data to write */ 532 if (count == 0) 533 goto exit; 534 535 /* lock this object */ 536 if (mutex_lock_interruptible(&dev->mutex)) { 537 retval = -ERESTARTSYS; 538 goto exit; 539 } 540 541 /* verify that the device wasn't unplugged */ 542 if (dev->intf == NULL) { 543 retval = -ENODEV; 544 printk(KERN_ERR "ldusb: No device or device unplugged %d\n", retval); 545 goto unlock_exit; 546 } 547 548 /* wait until previous transfer is finished */ 549 if (dev->interrupt_out_busy) { 550 if (file->f_flags & O_NONBLOCK) { 551 retval = -EAGAIN; 552 goto unlock_exit; 553 } 554 retval = wait_event_interruptible(dev->write_wait, !dev->interrupt_out_busy); 555 if (retval < 0) { 556 goto unlock_exit; 557 } 558 } 559 560 /* write the data into interrupt_out_buffer from userspace */ 561 bytes_to_write = min(count, write_buffer_size*dev->interrupt_out_endpoint_size); 562 if (bytes_to_write < count) 563 dev_warn(&dev->intf->dev, "Write buffer overflow, %zd bytes dropped\n", count-bytes_to_write); 564 dev_dbg(&dev->intf->dev, "%s: count = %zd, bytes_to_write = %zd\n", 565 __func__, count, bytes_to_write); 566 567 if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) { 568 retval = -EFAULT; 569 goto unlock_exit; 570 } 571 572 if (dev->interrupt_out_endpoint == NULL) { 573 /* try HID_REQ_SET_REPORT=9 on control_endpoint instead of interrupt_out_endpoint */ 574 retval = usb_control_msg(interface_to_usbdev(dev->intf), 575 usb_sndctrlpipe(interface_to_usbdev(dev->intf), 0), 576 9, 577 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT, 578 1 << 8, 0, 579 dev->interrupt_out_buffer, 580 bytes_to_write, 581 USB_CTRL_SET_TIMEOUT * HZ); 582 if (retval < 0) 583 dev_err(&dev->intf->dev, 584 "Couldn't submit HID_REQ_SET_REPORT %d\n", 585 retval); 586 goto unlock_exit; 587 } 588 589 /* send off the urb */ 590 usb_fill_int_urb(dev->interrupt_out_urb, 591 interface_to_usbdev(dev->intf), 592 usb_sndintpipe(interface_to_usbdev(dev->intf), 593 dev->interrupt_out_endpoint->bEndpointAddress), 594 dev->interrupt_out_buffer, 595 bytes_to_write, 596 ld_usb_interrupt_out_callback, 597 dev, 598 dev->interrupt_out_interval); 599 600 dev->interrupt_out_busy = 1; 601 wmb(); 602 603 retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL); 604 if (retval) { 605 dev->interrupt_out_busy = 0; 606 dev_err(&dev->intf->dev, 607 "Couldn't submit interrupt_out_urb %d\n", retval); 608 goto unlock_exit; 609 } 610 retval = bytes_to_write; 611 612 unlock_exit: 613 /* unlock the device */ 614 mutex_unlock(&dev->mutex); 615 616 exit: 617 return retval; 618 } 619 620 /* file operations needed when we register this driver */ 621 static const struct file_operations ld_usb_fops = { 622 .owner = THIS_MODULE, 623 .read = ld_usb_read, 624 .write = ld_usb_write, 625 .open = ld_usb_open, 626 .release = ld_usb_release, 627 .poll = ld_usb_poll, 628 .llseek = no_llseek, 629 }; 630 631 /* 632 * usb class driver info in order to get a minor number from the usb core, 633 * and to have the device registered with the driver core 634 */ 635 static struct usb_class_driver ld_usb_class = { 636 .name = "ldusb%d", 637 .fops = &ld_usb_fops, 638 .minor_base = USB_LD_MINOR_BASE, 639 }; 640 641 /** 642 * ld_usb_probe 643 * 644 * Called by the usb core when a new device is connected that it thinks 645 * this driver might be interested in. 646 */ 647 static int ld_usb_probe(struct usb_interface *intf, const struct usb_device_id *id) 648 { 649 struct usb_device *udev = interface_to_usbdev(intf); 650 struct ld_usb *dev = NULL; 651 struct usb_host_interface *iface_desc; 652 char *buffer; 653 int retval = -ENOMEM; 654 int res; 655 656 /* allocate memory for our device state and initialize it */ 657 658 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 659 if (!dev) 660 goto exit; 661 mutex_init(&dev->mutex); 662 spin_lock_init(&dev->rbsl); 663 dev->intf = intf; 664 init_waitqueue_head(&dev->read_wait); 665 init_waitqueue_head(&dev->write_wait); 666 667 /* workaround for early firmware versions on fast computers */ 668 if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) && 669 ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_CASSY) || 670 (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_COM3LAB)) && 671 (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) { 672 buffer = kmalloc(256, GFP_KERNEL); 673 if (!buffer) 674 goto error; 675 /* usb_string makes SETUP+STALL to leave always ControlReadLoop */ 676 usb_string(udev, 255, buffer, 256); 677 kfree(buffer); 678 } 679 680 iface_desc = intf->cur_altsetting; 681 682 res = usb_find_last_int_in_endpoint(iface_desc, 683 &dev->interrupt_in_endpoint); 684 if (res) { 685 dev_err(&intf->dev, "Interrupt in endpoint not found\n"); 686 retval = res; 687 goto error; 688 } 689 690 res = usb_find_last_int_out_endpoint(iface_desc, 691 &dev->interrupt_out_endpoint); 692 if (res) 693 dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n"); 694 695 dev->interrupt_in_endpoint_size = usb_endpoint_maxp(dev->interrupt_in_endpoint); 696 dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL); 697 if (!dev->ring_buffer) 698 goto error; 699 dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL); 700 if (!dev->interrupt_in_buffer) 701 goto error; 702 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL); 703 if (!dev->interrupt_in_urb) 704 goto error; 705 dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? usb_endpoint_maxp(dev->interrupt_out_endpoint) : 706 udev->descriptor.bMaxPacketSize0; 707 dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL); 708 if (!dev->interrupt_out_buffer) 709 goto error; 710 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL); 711 if (!dev->interrupt_out_urb) 712 goto error; 713 dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval; 714 if (dev->interrupt_out_endpoint) 715 dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval; 716 717 /* we can register the device now, as it is ready */ 718 usb_set_intfdata(intf, dev); 719 720 retval = usb_register_dev(intf, &ld_usb_class); 721 if (retval) { 722 /* something prevented us from registering this driver */ 723 dev_err(&intf->dev, "Not able to get a minor for this device.\n"); 724 usb_set_intfdata(intf, NULL); 725 goto error; 726 } 727 728 /* let the user know what node this device is now attached to */ 729 dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n", 730 (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor); 731 732 exit: 733 return retval; 734 735 error: 736 ld_usb_delete(dev); 737 738 return retval; 739 } 740 741 /** 742 * ld_usb_disconnect 743 * 744 * Called by the usb core when the device is removed from the system. 745 */ 746 static void ld_usb_disconnect(struct usb_interface *intf) 747 { 748 struct ld_usb *dev; 749 int minor; 750 751 dev = usb_get_intfdata(intf); 752 usb_set_intfdata(intf, NULL); 753 754 minor = intf->minor; 755 756 /* give back our minor */ 757 usb_deregister_dev(intf, &ld_usb_class); 758 759 mutex_lock(&dev->mutex); 760 761 /* if the device is not opened, then we clean up right now */ 762 if (!dev->open_count) { 763 mutex_unlock(&dev->mutex); 764 ld_usb_delete(dev); 765 } else { 766 dev->intf = NULL; 767 /* wake up pollers */ 768 wake_up_interruptible_all(&dev->read_wait); 769 wake_up_interruptible_all(&dev->write_wait); 770 mutex_unlock(&dev->mutex); 771 } 772 773 dev_info(&intf->dev, "LD USB Device #%d now disconnected\n", 774 (minor - USB_LD_MINOR_BASE)); 775 } 776 777 /* usb specific object needed to register this driver with the usb subsystem */ 778 static struct usb_driver ld_usb_driver = { 779 .name = "ldusb", 780 .probe = ld_usb_probe, 781 .disconnect = ld_usb_disconnect, 782 .id_table = ld_usb_table, 783 }; 784 785 module_usb_driver(ld_usb_driver); 786 787