1 // SPDX-License-Identifier: GPL-2.0+ 2 /** 3 * Generic USB driver for report based interrupt in/out devices 4 * like LD Didactic's USB devices. LD Didactic's USB devices are 5 * HID devices which do not use HID report definitons (they use 6 * raw interrupt in and our reports only for communication). 7 * 8 * This driver uses a ring buffer for time critical reading of 9 * interrupt in reports and provides read and write methods for 10 * raw interrupt reports (similar to the Windows HID driver). 11 * Devices based on the book USB COMPLETE by Jan Axelson may need 12 * such a compatibility to the Windows HID driver. 13 * 14 * Copyright (C) 2005 Michael Hund <mhund@ld-didactic.de> 15 * 16 * Derived from Lego USB Tower driver 17 * Copyright (C) 2003 David Glance <advidgsf@sourceforge.net> 18 * 2001-2004 Juergen Stuber <starblue@users.sourceforge.net> 19 */ 20 21 #include <linux/kernel.h> 22 #include <linux/errno.h> 23 #include <linux/slab.h> 24 #include <linux/module.h> 25 #include <linux/mutex.h> 26 27 #include <linux/uaccess.h> 28 #include <linux/input.h> 29 #include <linux/usb.h> 30 #include <linux/poll.h> 31 32 /* Define these values to match your devices */ 33 #define USB_VENDOR_ID_LD 0x0f11 /* USB Vendor ID of LD Didactic GmbH */ 34 #define USB_DEVICE_ID_LD_CASSY 0x1000 /* USB Product ID of CASSY-S modules with 8 bytes endpoint size */ 35 #define USB_DEVICE_ID_LD_CASSY2 0x1001 /* USB Product ID of CASSY-S modules with 64 bytes endpoint size */ 36 #define USB_DEVICE_ID_LD_POCKETCASSY 0x1010 /* USB Product ID of Pocket-CASSY */ 37 #define USB_DEVICE_ID_LD_POCKETCASSY2 0x1011 /* USB Product ID of Pocket-CASSY 2 (reserved) */ 38 #define USB_DEVICE_ID_LD_MOBILECASSY 0x1020 /* USB Product ID of Mobile-CASSY */ 39 #define USB_DEVICE_ID_LD_MOBILECASSY2 0x1021 /* USB Product ID of Mobile-CASSY 2 (reserved) */ 40 #define USB_DEVICE_ID_LD_MICROCASSYVOLTAGE 0x1031 /* USB Product ID of Micro-CASSY Voltage */ 41 #define USB_DEVICE_ID_LD_MICROCASSYCURRENT 0x1032 /* USB Product ID of Micro-CASSY Current */ 42 #define USB_DEVICE_ID_LD_MICROCASSYTIME 0x1033 /* USB Product ID of Micro-CASSY Time (reserved) */ 43 #define USB_DEVICE_ID_LD_MICROCASSYTEMPERATURE 0x1035 /* USB Product ID of Micro-CASSY Temperature */ 44 #define USB_DEVICE_ID_LD_MICROCASSYPH 0x1038 /* USB Product ID of Micro-CASSY pH */ 45 #define USB_DEVICE_ID_LD_JWM 0x1080 /* USB Product ID of Joule and Wattmeter */ 46 #define USB_DEVICE_ID_LD_DMMP 0x1081 /* USB Product ID of Digital Multimeter P (reserved) */ 47 #define USB_DEVICE_ID_LD_UMIP 0x1090 /* USB Product ID of UMI P */ 48 #define USB_DEVICE_ID_LD_UMIC 0x10A0 /* USB Product ID of UMI C */ 49 #define USB_DEVICE_ID_LD_UMIB 0x10B0 /* USB Product ID of UMI B */ 50 #define USB_DEVICE_ID_LD_XRAY 0x1100 /* USB Product ID of X-Ray Apparatus 55481 */ 51 #define USB_DEVICE_ID_LD_XRAY2 0x1101 /* USB Product ID of X-Ray Apparatus 554800 */ 52 #define USB_DEVICE_ID_LD_XRAYCT 0x1110 /* USB Product ID of X-Ray Apparatus CT 554821*/ 53 #define USB_DEVICE_ID_LD_VIDEOCOM 0x1200 /* USB Product ID of VideoCom */ 54 #define USB_DEVICE_ID_LD_MOTOR 0x1210 /* USB Product ID of Motor (reserved) */ 55 #define USB_DEVICE_ID_LD_COM3LAB 0x2000 /* USB Product ID of COM3LAB */ 56 #define USB_DEVICE_ID_LD_TELEPORT 0x2010 /* USB Product ID of Terminal Adapter */ 57 #define USB_DEVICE_ID_LD_NETWORKANALYSER 0x2020 /* USB Product ID of Network Analyser */ 58 #define USB_DEVICE_ID_LD_POWERCONTROL 0x2030 /* USB Product ID of Converter Control Unit */ 59 #define USB_DEVICE_ID_LD_MACHINETEST 0x2040 /* USB Product ID of Machine Test System */ 60 #define USB_DEVICE_ID_LD_MOSTANALYSER 0x2050 /* USB Product ID of MOST Protocol Analyser */ 61 #define USB_DEVICE_ID_LD_MOSTANALYSER2 0x2051 /* USB Product ID of MOST Protocol Analyser 2 */ 62 #define USB_DEVICE_ID_LD_ABSESP 0x2060 /* USB Product ID of ABS ESP */ 63 #define USB_DEVICE_ID_LD_AUTODATABUS 0x2070 /* USB Product ID of Automotive Data Buses */ 64 #define USB_DEVICE_ID_LD_MCT 0x2080 /* USB Product ID of Microcontroller technique */ 65 #define USB_DEVICE_ID_LD_HYBRID 0x2090 /* USB Product ID of Automotive Hybrid */ 66 #define USB_DEVICE_ID_LD_HEATCONTROL 0x20A0 /* USB Product ID of Heat control */ 67 68 #ifdef CONFIG_USB_DYNAMIC_MINORS 69 #define USB_LD_MINOR_BASE 0 70 #else 71 #define USB_LD_MINOR_BASE 176 72 #endif 73 74 /* table of devices that work with this driver */ 75 static const struct usb_device_id ld_usb_table[] = { 76 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY) }, 77 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY2) }, 78 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY) }, 79 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY2) }, 80 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY) }, 81 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY2) }, 82 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYVOLTAGE) }, 83 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYCURRENT) }, 84 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYTIME) }, 85 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYTEMPERATURE) }, 86 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYPH) }, 87 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_JWM) }, 88 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_DMMP) }, 89 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIP) }, 90 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIC) }, 91 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIB) }, 92 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY) }, 93 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY2) }, 94 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_VIDEOCOM) }, 95 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOTOR) }, 96 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_COM3LAB) }, 97 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_TELEPORT) }, 98 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_NETWORKANALYSER) }, 99 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POWERCONTROL) }, 100 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MACHINETEST) }, 101 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOSTANALYSER) }, 102 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOSTANALYSER2) }, 103 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_ABSESP) }, 104 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_AUTODATABUS) }, 105 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MCT) }, 106 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_HYBRID) }, 107 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_HEATCONTROL) }, 108 { } /* Terminating entry */ 109 }; 110 MODULE_DEVICE_TABLE(usb, ld_usb_table); 111 MODULE_AUTHOR("Michael Hund <mhund@ld-didactic.de>"); 112 MODULE_DESCRIPTION("LD USB Driver"); 113 MODULE_LICENSE("GPL"); 114 MODULE_SUPPORTED_DEVICE("LD USB Devices"); 115 116 /* All interrupt in transfers are collected in a ring buffer to 117 * avoid racing conditions and get better performance of the driver. 118 */ 119 static int ring_buffer_size = 128; 120 module_param(ring_buffer_size, int, 0000); 121 MODULE_PARM_DESC(ring_buffer_size, "Read ring buffer size in reports"); 122 123 /* The write_buffer can contain more than one interrupt out transfer. 124 */ 125 static int write_buffer_size = 10; 126 module_param(write_buffer_size, int, 0000); 127 MODULE_PARM_DESC(write_buffer_size, "Write buffer size in reports"); 128 129 /* As of kernel version 2.6.4 ehci-hcd uses an 130 * "only one interrupt transfer per frame" shortcut 131 * to simplify the scheduling of periodic transfers. 132 * This conflicts with our standard 1ms intervals for in and out URBs. 133 * We use default intervals of 2ms for in and 2ms for out transfers, 134 * which should be fast enough. 135 * Increase the interval to allow more devices that do interrupt transfers, 136 * or set to 1 to use the standard interval from the endpoint descriptors. 137 */ 138 static int min_interrupt_in_interval = 2; 139 module_param(min_interrupt_in_interval, int, 0000); 140 MODULE_PARM_DESC(min_interrupt_in_interval, "Minimum interrupt in interval in ms"); 141 142 static int min_interrupt_out_interval = 2; 143 module_param(min_interrupt_out_interval, int, 0000); 144 MODULE_PARM_DESC(min_interrupt_out_interval, "Minimum interrupt out interval in ms"); 145 146 /* Structure to hold all of our device specific stuff */ 147 struct ld_usb { 148 struct mutex mutex; /* locks this structure */ 149 struct usb_interface *intf; /* save off the usb interface pointer */ 150 151 int open_count; /* number of times this port has been opened */ 152 153 char *ring_buffer; 154 unsigned int ring_head; 155 unsigned int ring_tail; 156 157 wait_queue_head_t read_wait; 158 wait_queue_head_t write_wait; 159 160 char *interrupt_in_buffer; 161 struct usb_endpoint_descriptor *interrupt_in_endpoint; 162 struct urb *interrupt_in_urb; 163 int interrupt_in_interval; 164 size_t interrupt_in_endpoint_size; 165 int interrupt_in_running; 166 int interrupt_in_done; 167 int buffer_overflow; 168 spinlock_t rbsl; 169 170 char *interrupt_out_buffer; 171 struct usb_endpoint_descriptor *interrupt_out_endpoint; 172 struct urb *interrupt_out_urb; 173 int interrupt_out_interval; 174 size_t interrupt_out_endpoint_size; 175 int interrupt_out_busy; 176 }; 177 178 static struct usb_driver ld_usb_driver; 179 180 /** 181 * ld_usb_abort_transfers 182 * aborts transfers and frees associated data structures 183 */ 184 static void ld_usb_abort_transfers(struct ld_usb *dev) 185 { 186 /* shutdown transfer */ 187 if (dev->interrupt_in_running) { 188 dev->interrupt_in_running = 0; 189 if (dev->intf) 190 usb_kill_urb(dev->interrupt_in_urb); 191 } 192 if (dev->interrupt_out_busy) 193 if (dev->intf) 194 usb_kill_urb(dev->interrupt_out_urb); 195 } 196 197 /** 198 * ld_usb_delete 199 */ 200 static void ld_usb_delete(struct ld_usb *dev) 201 { 202 ld_usb_abort_transfers(dev); 203 204 /* free data structures */ 205 usb_free_urb(dev->interrupt_in_urb); 206 usb_free_urb(dev->interrupt_out_urb); 207 kfree(dev->ring_buffer); 208 kfree(dev->interrupt_in_buffer); 209 kfree(dev->interrupt_out_buffer); 210 kfree(dev); 211 } 212 213 /** 214 * ld_usb_interrupt_in_callback 215 */ 216 static void ld_usb_interrupt_in_callback(struct urb *urb) 217 { 218 struct ld_usb *dev = urb->context; 219 size_t *actual_buffer; 220 unsigned int next_ring_head; 221 int status = urb->status; 222 int retval; 223 224 if (status) { 225 if (status == -ENOENT || 226 status == -ECONNRESET || 227 status == -ESHUTDOWN) { 228 goto exit; 229 } else { 230 dev_dbg(&dev->intf->dev, 231 "%s: nonzero status received: %d\n", __func__, 232 status); 233 spin_lock(&dev->rbsl); 234 goto resubmit; /* maybe we can recover */ 235 } 236 } 237 238 spin_lock(&dev->rbsl); 239 if (urb->actual_length > 0) { 240 next_ring_head = (dev->ring_head+1) % ring_buffer_size; 241 if (next_ring_head != dev->ring_tail) { 242 actual_buffer = (size_t *)(dev->ring_buffer + dev->ring_head * (sizeof(size_t)+dev->interrupt_in_endpoint_size)); 243 /* actual_buffer gets urb->actual_length + interrupt_in_buffer */ 244 *actual_buffer = urb->actual_length; 245 memcpy(actual_buffer+1, dev->interrupt_in_buffer, urb->actual_length); 246 dev->ring_head = next_ring_head; 247 dev_dbg(&dev->intf->dev, "%s: received %d bytes\n", 248 __func__, urb->actual_length); 249 } else { 250 dev_warn(&dev->intf->dev, 251 "Ring buffer overflow, %d bytes dropped\n", 252 urb->actual_length); 253 dev->buffer_overflow = 1; 254 } 255 } 256 257 resubmit: 258 /* resubmit if we're still running */ 259 if (dev->interrupt_in_running && !dev->buffer_overflow && dev->intf) { 260 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC); 261 if (retval) { 262 dev_err(&dev->intf->dev, 263 "usb_submit_urb failed (%d)\n", retval); 264 dev->buffer_overflow = 1; 265 } 266 } 267 spin_unlock(&dev->rbsl); 268 exit: 269 dev->interrupt_in_done = 1; 270 wake_up_interruptible(&dev->read_wait); 271 } 272 273 /** 274 * ld_usb_interrupt_out_callback 275 */ 276 static void ld_usb_interrupt_out_callback(struct urb *urb) 277 { 278 struct ld_usb *dev = urb->context; 279 int status = urb->status; 280 281 /* sync/async unlink faults aren't errors */ 282 if (status && !(status == -ENOENT || 283 status == -ECONNRESET || 284 status == -ESHUTDOWN)) 285 dev_dbg(&dev->intf->dev, 286 "%s - nonzero write interrupt status received: %d\n", 287 __func__, status); 288 289 dev->interrupt_out_busy = 0; 290 wake_up_interruptible(&dev->write_wait); 291 } 292 293 /** 294 * ld_usb_open 295 */ 296 static int ld_usb_open(struct inode *inode, struct file *file) 297 { 298 struct ld_usb *dev; 299 int subminor; 300 int retval; 301 struct usb_interface *interface; 302 303 nonseekable_open(inode, file); 304 subminor = iminor(inode); 305 306 interface = usb_find_interface(&ld_usb_driver, subminor); 307 308 if (!interface) { 309 printk(KERN_ERR "%s - error, can't find device for minor %d\n", 310 __func__, subminor); 311 return -ENODEV; 312 } 313 314 dev = usb_get_intfdata(interface); 315 316 if (!dev) 317 return -ENODEV; 318 319 /* lock this device */ 320 if (mutex_lock_interruptible(&dev->mutex)) 321 return -ERESTARTSYS; 322 323 /* allow opening only once */ 324 if (dev->open_count) { 325 retval = -EBUSY; 326 goto unlock_exit; 327 } 328 dev->open_count = 1; 329 330 /* initialize in direction */ 331 dev->ring_head = 0; 332 dev->ring_tail = 0; 333 dev->buffer_overflow = 0; 334 usb_fill_int_urb(dev->interrupt_in_urb, 335 interface_to_usbdev(interface), 336 usb_rcvintpipe(interface_to_usbdev(interface), 337 dev->interrupt_in_endpoint->bEndpointAddress), 338 dev->interrupt_in_buffer, 339 dev->interrupt_in_endpoint_size, 340 ld_usb_interrupt_in_callback, 341 dev, 342 dev->interrupt_in_interval); 343 344 dev->interrupt_in_running = 1; 345 dev->interrupt_in_done = 0; 346 347 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL); 348 if (retval) { 349 dev_err(&interface->dev, "Couldn't submit interrupt_in_urb %d\n", retval); 350 dev->interrupt_in_running = 0; 351 dev->open_count = 0; 352 goto unlock_exit; 353 } 354 355 /* save device in the file's private structure */ 356 file->private_data = dev; 357 358 unlock_exit: 359 mutex_unlock(&dev->mutex); 360 361 return retval; 362 } 363 364 /** 365 * ld_usb_release 366 */ 367 static int ld_usb_release(struct inode *inode, struct file *file) 368 { 369 struct ld_usb *dev; 370 int retval = 0; 371 372 dev = file->private_data; 373 374 if (dev == NULL) { 375 retval = -ENODEV; 376 goto exit; 377 } 378 379 if (mutex_lock_interruptible(&dev->mutex)) { 380 retval = -ERESTARTSYS; 381 goto exit; 382 } 383 384 if (dev->open_count != 1) { 385 retval = -ENODEV; 386 goto unlock_exit; 387 } 388 if (dev->intf == NULL) { 389 /* the device was unplugged before the file was released */ 390 mutex_unlock(&dev->mutex); 391 /* unlock here as ld_usb_delete frees dev */ 392 ld_usb_delete(dev); 393 goto exit; 394 } 395 396 /* wait until write transfer is finished */ 397 if (dev->interrupt_out_busy) 398 wait_event_interruptible_timeout(dev->write_wait, !dev->interrupt_out_busy, 2 * HZ); 399 ld_usb_abort_transfers(dev); 400 dev->open_count = 0; 401 402 unlock_exit: 403 mutex_unlock(&dev->mutex); 404 405 exit: 406 return retval; 407 } 408 409 /** 410 * ld_usb_poll 411 */ 412 static __poll_t ld_usb_poll(struct file *file, poll_table *wait) 413 { 414 struct ld_usb *dev; 415 __poll_t mask = 0; 416 417 dev = file->private_data; 418 419 if (!dev->intf) 420 return EPOLLERR | EPOLLHUP; 421 422 poll_wait(file, &dev->read_wait, wait); 423 poll_wait(file, &dev->write_wait, wait); 424 425 if (dev->ring_head != dev->ring_tail) 426 mask |= EPOLLIN | EPOLLRDNORM; 427 if (!dev->interrupt_out_busy) 428 mask |= EPOLLOUT | EPOLLWRNORM; 429 430 return mask; 431 } 432 433 /** 434 * ld_usb_read 435 */ 436 static ssize_t ld_usb_read(struct file *file, char __user *buffer, size_t count, 437 loff_t *ppos) 438 { 439 struct ld_usb *dev; 440 size_t *actual_buffer; 441 size_t bytes_to_read; 442 int retval = 0; 443 int rv; 444 445 dev = file->private_data; 446 447 /* verify that we actually have some data to read */ 448 if (count == 0) 449 goto exit; 450 451 /* lock this object */ 452 if (mutex_lock_interruptible(&dev->mutex)) { 453 retval = -ERESTARTSYS; 454 goto exit; 455 } 456 457 /* verify that the device wasn't unplugged */ 458 if (dev->intf == NULL) { 459 retval = -ENODEV; 460 printk(KERN_ERR "ldusb: No device or device unplugged %d\n", retval); 461 goto unlock_exit; 462 } 463 464 /* wait for data */ 465 spin_lock_irq(&dev->rbsl); 466 if (dev->ring_head == dev->ring_tail) { 467 dev->interrupt_in_done = 0; 468 spin_unlock_irq(&dev->rbsl); 469 if (file->f_flags & O_NONBLOCK) { 470 retval = -EAGAIN; 471 goto unlock_exit; 472 } 473 retval = wait_event_interruptible(dev->read_wait, dev->interrupt_in_done); 474 if (retval < 0) 475 goto unlock_exit; 476 } else { 477 spin_unlock_irq(&dev->rbsl); 478 } 479 480 /* actual_buffer contains actual_length + interrupt_in_buffer */ 481 actual_buffer = (size_t *)(dev->ring_buffer + dev->ring_tail * (sizeof(size_t)+dev->interrupt_in_endpoint_size)); 482 bytes_to_read = min(count, *actual_buffer); 483 if (bytes_to_read < *actual_buffer) 484 dev_warn(&dev->intf->dev, "Read buffer overflow, %zd bytes dropped\n", 485 *actual_buffer-bytes_to_read); 486 487 /* copy one interrupt_in_buffer from ring_buffer into userspace */ 488 if (copy_to_user(buffer, actual_buffer+1, bytes_to_read)) { 489 retval = -EFAULT; 490 goto unlock_exit; 491 } 492 dev->ring_tail = (dev->ring_tail+1) % ring_buffer_size; 493 494 retval = bytes_to_read; 495 496 spin_lock_irq(&dev->rbsl); 497 if (dev->buffer_overflow) { 498 dev->buffer_overflow = 0; 499 spin_unlock_irq(&dev->rbsl); 500 rv = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL); 501 if (rv < 0) 502 dev->buffer_overflow = 1; 503 } else { 504 spin_unlock_irq(&dev->rbsl); 505 } 506 507 unlock_exit: 508 /* unlock the device */ 509 mutex_unlock(&dev->mutex); 510 511 exit: 512 return retval; 513 } 514 515 /** 516 * ld_usb_write 517 */ 518 static ssize_t ld_usb_write(struct file *file, const char __user *buffer, 519 size_t count, loff_t *ppos) 520 { 521 struct ld_usb *dev; 522 size_t bytes_to_write; 523 int retval = 0; 524 525 dev = file->private_data; 526 527 /* verify that we actually have some data to write */ 528 if (count == 0) 529 goto exit; 530 531 /* lock this object */ 532 if (mutex_lock_interruptible(&dev->mutex)) { 533 retval = -ERESTARTSYS; 534 goto exit; 535 } 536 537 /* verify that the device wasn't unplugged */ 538 if (dev->intf == NULL) { 539 retval = -ENODEV; 540 printk(KERN_ERR "ldusb: No device or device unplugged %d\n", retval); 541 goto unlock_exit; 542 } 543 544 /* wait until previous transfer is finished */ 545 if (dev->interrupt_out_busy) { 546 if (file->f_flags & O_NONBLOCK) { 547 retval = -EAGAIN; 548 goto unlock_exit; 549 } 550 retval = wait_event_interruptible(dev->write_wait, !dev->interrupt_out_busy); 551 if (retval < 0) { 552 goto unlock_exit; 553 } 554 } 555 556 /* write the data into interrupt_out_buffer from userspace */ 557 bytes_to_write = min(count, write_buffer_size*dev->interrupt_out_endpoint_size); 558 if (bytes_to_write < count) 559 dev_warn(&dev->intf->dev, "Write buffer overflow, %zd bytes dropped\n", count-bytes_to_write); 560 dev_dbg(&dev->intf->dev, "%s: count = %zd, bytes_to_write = %zd\n", 561 __func__, count, bytes_to_write); 562 563 if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) { 564 retval = -EFAULT; 565 goto unlock_exit; 566 } 567 568 if (dev->interrupt_out_endpoint == NULL) { 569 /* try HID_REQ_SET_REPORT=9 on control_endpoint instead of interrupt_out_endpoint */ 570 retval = usb_control_msg(interface_to_usbdev(dev->intf), 571 usb_sndctrlpipe(interface_to_usbdev(dev->intf), 0), 572 9, 573 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT, 574 1 << 8, 0, 575 dev->interrupt_out_buffer, 576 bytes_to_write, 577 USB_CTRL_SET_TIMEOUT * HZ); 578 if (retval < 0) 579 dev_err(&dev->intf->dev, 580 "Couldn't submit HID_REQ_SET_REPORT %d\n", 581 retval); 582 goto unlock_exit; 583 } 584 585 /* send off the urb */ 586 usb_fill_int_urb(dev->interrupt_out_urb, 587 interface_to_usbdev(dev->intf), 588 usb_sndintpipe(interface_to_usbdev(dev->intf), 589 dev->interrupt_out_endpoint->bEndpointAddress), 590 dev->interrupt_out_buffer, 591 bytes_to_write, 592 ld_usb_interrupt_out_callback, 593 dev, 594 dev->interrupt_out_interval); 595 596 dev->interrupt_out_busy = 1; 597 wmb(); 598 599 retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL); 600 if (retval) { 601 dev->interrupt_out_busy = 0; 602 dev_err(&dev->intf->dev, 603 "Couldn't submit interrupt_out_urb %d\n", retval); 604 goto unlock_exit; 605 } 606 retval = bytes_to_write; 607 608 unlock_exit: 609 /* unlock the device */ 610 mutex_unlock(&dev->mutex); 611 612 exit: 613 return retval; 614 } 615 616 /* file operations needed when we register this driver */ 617 static const struct file_operations ld_usb_fops = { 618 .owner = THIS_MODULE, 619 .read = ld_usb_read, 620 .write = ld_usb_write, 621 .open = ld_usb_open, 622 .release = ld_usb_release, 623 .poll = ld_usb_poll, 624 .llseek = no_llseek, 625 }; 626 627 /* 628 * usb class driver info in order to get a minor number from the usb core, 629 * and to have the device registered with the driver core 630 */ 631 static struct usb_class_driver ld_usb_class = { 632 .name = "ldusb%d", 633 .fops = &ld_usb_fops, 634 .minor_base = USB_LD_MINOR_BASE, 635 }; 636 637 /** 638 * ld_usb_probe 639 * 640 * Called by the usb core when a new device is connected that it thinks 641 * this driver might be interested in. 642 */ 643 static int ld_usb_probe(struct usb_interface *intf, const struct usb_device_id *id) 644 { 645 struct usb_device *udev = interface_to_usbdev(intf); 646 struct ld_usb *dev = NULL; 647 struct usb_host_interface *iface_desc; 648 char *buffer; 649 int retval = -ENOMEM; 650 int res; 651 652 /* allocate memory for our device state and initialize it */ 653 654 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 655 if (!dev) 656 goto exit; 657 mutex_init(&dev->mutex); 658 spin_lock_init(&dev->rbsl); 659 dev->intf = intf; 660 init_waitqueue_head(&dev->read_wait); 661 init_waitqueue_head(&dev->write_wait); 662 663 /* workaround for early firmware versions on fast computers */ 664 if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) && 665 ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_CASSY) || 666 (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_COM3LAB)) && 667 (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) { 668 buffer = kmalloc(256, GFP_KERNEL); 669 if (!buffer) 670 goto error; 671 /* usb_string makes SETUP+STALL to leave always ControlReadLoop */ 672 usb_string(udev, 255, buffer, 256); 673 kfree(buffer); 674 } 675 676 iface_desc = intf->cur_altsetting; 677 678 res = usb_find_last_int_in_endpoint(iface_desc, 679 &dev->interrupt_in_endpoint); 680 if (res) { 681 dev_err(&intf->dev, "Interrupt in endpoint not found\n"); 682 retval = res; 683 goto error; 684 } 685 686 res = usb_find_last_int_out_endpoint(iface_desc, 687 &dev->interrupt_out_endpoint); 688 if (res) 689 dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n"); 690 691 dev->interrupt_in_endpoint_size = usb_endpoint_maxp(dev->interrupt_in_endpoint); 692 dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL); 693 if (!dev->ring_buffer) 694 goto error; 695 dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL); 696 if (!dev->interrupt_in_buffer) 697 goto error; 698 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL); 699 if (!dev->interrupt_in_urb) 700 goto error; 701 dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? usb_endpoint_maxp(dev->interrupt_out_endpoint) : 702 udev->descriptor.bMaxPacketSize0; 703 dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL); 704 if (!dev->interrupt_out_buffer) 705 goto error; 706 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL); 707 if (!dev->interrupt_out_urb) 708 goto error; 709 dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval; 710 if (dev->interrupt_out_endpoint) 711 dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval; 712 713 /* we can register the device now, as it is ready */ 714 usb_set_intfdata(intf, dev); 715 716 retval = usb_register_dev(intf, &ld_usb_class); 717 if (retval) { 718 /* something prevented us from registering this driver */ 719 dev_err(&intf->dev, "Not able to get a minor for this device.\n"); 720 usb_set_intfdata(intf, NULL); 721 goto error; 722 } 723 724 /* let the user know what node this device is now attached to */ 725 dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n", 726 (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor); 727 728 exit: 729 return retval; 730 731 error: 732 ld_usb_delete(dev); 733 734 return retval; 735 } 736 737 /** 738 * ld_usb_disconnect 739 * 740 * Called by the usb core when the device is removed from the system. 741 */ 742 static void ld_usb_disconnect(struct usb_interface *intf) 743 { 744 struct ld_usb *dev; 745 int minor; 746 747 dev = usb_get_intfdata(intf); 748 usb_set_intfdata(intf, NULL); 749 750 minor = intf->minor; 751 752 /* give back our minor */ 753 usb_deregister_dev(intf, &ld_usb_class); 754 755 mutex_lock(&dev->mutex); 756 757 /* if the device is not opened, then we clean up right now */ 758 if (!dev->open_count) { 759 mutex_unlock(&dev->mutex); 760 ld_usb_delete(dev); 761 } else { 762 dev->intf = NULL; 763 /* wake up pollers */ 764 wake_up_interruptible_all(&dev->read_wait); 765 wake_up_interruptible_all(&dev->write_wait); 766 mutex_unlock(&dev->mutex); 767 } 768 769 dev_info(&intf->dev, "LD USB Device #%d now disconnected\n", 770 (minor - USB_LD_MINOR_BASE)); 771 } 772 773 /* usb specific object needed to register this driver with the usb subsystem */ 774 static struct usb_driver ld_usb_driver = { 775 .name = "ldusb", 776 .probe = ld_usb_probe, 777 .disconnect = ld_usb_disconnect, 778 .id_table = ld_usb_table, 779 }; 780 781 module_usb_driver(ld_usb_driver); 782 783