1// SPDX-License-Identifier: GPL-2.0+ 2/* 3 * f_printer.c - USB printer function driver 4 * 5 * Copied from drivers/usb/gadget/legacy/printer.c, 6 * which was: 7 * 8 * printer.c -- Printer gadget driver 9 * 10 * Copyright (C) 2003-2005 David Brownell 11 * Copyright (C) 2006 Craig W. Nadler 12 */ 13 14#include <linux/module.h> 15#include <linux/kernel.h> 16#include <linux/delay.h> 17#include <linux/ioport.h> 18#include <linux/sched.h> 19#include <linux/slab.h> 20#include <linux/mutex.h> 21#include <linux/errno.h> 22#include <linux/init.h> 23#include <linux/idr.h> 24#include <linux/timer.h> 25#include <linux/list.h> 26#include <linux/interrupt.h> 27#include <linux/device.h> 28#include <linux/moduleparam.h> 29#include <linux/fs.h> 30#include <linux/poll.h> 31#include <linux/types.h> 32#include <linux/ctype.h> 33#include <linux/cdev.h> 34#include <linux/kref.h> 35 36#include <asm/byteorder.h> 37#include <linux/io.h> 38#include <linux/irq.h> 39#include <linux/uaccess.h> 40#include <asm/unaligned.h> 41 42#include <linux/usb/ch9.h> 43#include <linux/usb/composite.h> 44#include <linux/usb/gadget.h> 45#include <linux/usb/g_printer.h> 46 47#include "u_printer.h" 48 49#define PRINTER_MINORS 4 50#define GET_DEVICE_ID 0 51#define GET_PORT_STATUS 1 52#define SOFT_RESET 2 53 54#define DEFAULT_Q_LEN 10 /* same as legacy g_printer gadget */ 55 56static int major, minors; 57static const struct class usb_gadget_class = { 58 .name = "usb_printer_gadget", 59}; 60 61static DEFINE_IDA(printer_ida); 62static DEFINE_MUTEX(printer_ida_lock); /* protects access do printer_ida */ 63 64/*-------------------------------------------------------------------------*/ 65 66struct printer_dev { 67 spinlock_t lock; /* lock this structure */ 68 /* lock buffer lists during read/write calls */ 69 struct mutex lock_printer_io; 70 struct usb_gadget *gadget; 71 s8 interface; 72 struct usb_ep *in_ep, *out_ep; 73 struct kref kref; 74 struct list_head rx_reqs; /* List of free RX structs */ 75 struct list_head rx_reqs_active; /* List of Active RX xfers */ 76 struct list_head rx_buffers; /* List of completed xfers */ 77 /* wait until there is data to be read. */ 78 wait_queue_head_t rx_wait; 79 struct list_head tx_reqs; /* List of free TX structs */ 80 struct list_head tx_reqs_active; /* List of Active TX xfers */ 81 /* Wait until there are write buffers available to use. */ 82 wait_queue_head_t tx_wait; 83 /* Wait until all write buffers have been sent. */ 84 wait_queue_head_t tx_flush_wait; 85 struct usb_request *current_rx_req; 86 size_t current_rx_bytes; 87 u8 *current_rx_buf; 88 u8 printer_status; 89 u8 reset_printer; 90 int minor; 91 struct cdev printer_cdev; 92 u8 printer_cdev_open; 93 wait_queue_head_t wait; 94 unsigned q_len; 95 char **pnp_string; /* We don't own memory! */ 96 struct usb_function function; 97}; 98 99static inline struct printer_dev *func_to_printer(struct usb_function *f) 100{ 101 return container_of(f, struct printer_dev, function); 102} 103 104/*-------------------------------------------------------------------------*/ 105 106/* 107 * DESCRIPTORS ... most are static, but strings and (full) configuration 108 * descriptors are built on demand. 109 */ 110 111/* holds our biggest descriptor */ 112#define USB_DESC_BUFSIZE 256 113#define USB_BUFSIZE 8192 114 115static struct usb_interface_descriptor intf_desc = { 116 .bLength = sizeof(intf_desc), 117 .bDescriptorType = USB_DT_INTERFACE, 118 .bNumEndpoints = 2, 119 .bInterfaceClass = USB_CLASS_PRINTER, 120 .bInterfaceSubClass = 1, /* Printer Sub-Class */ 121 .bInterfaceProtocol = 2, /* Bi-Directional */ 122 .iInterface = 0 123}; 124 125static struct usb_endpoint_descriptor fs_ep_in_desc = { 126 .bLength = USB_DT_ENDPOINT_SIZE, 127 .bDescriptorType = USB_DT_ENDPOINT, 128 .bEndpointAddress = USB_DIR_IN, 129 .bmAttributes = USB_ENDPOINT_XFER_BULK 130}; 131 132static struct usb_endpoint_descriptor fs_ep_out_desc = { 133 .bLength = USB_DT_ENDPOINT_SIZE, 134 .bDescriptorType = USB_DT_ENDPOINT, 135 .bEndpointAddress = USB_DIR_OUT, 136 .bmAttributes = USB_ENDPOINT_XFER_BULK 137}; 138 139static struct usb_descriptor_header *fs_printer_function[] = { 140 (struct usb_descriptor_header *) &intf_desc, 141 (struct usb_descriptor_header *) &fs_ep_in_desc, 142 (struct usb_descriptor_header *) &fs_ep_out_desc, 143 NULL 144}; 145 146/* 147 * usb 2.0 devices need to expose both high speed and full speed 148 * descriptors, unless they only run at full speed. 149 */ 150 151static struct usb_endpoint_descriptor hs_ep_in_desc = { 152 .bLength = USB_DT_ENDPOINT_SIZE, 153 .bDescriptorType = USB_DT_ENDPOINT, 154 .bmAttributes = USB_ENDPOINT_XFER_BULK, 155 .wMaxPacketSize = cpu_to_le16(512) 156}; 157 158static struct usb_endpoint_descriptor hs_ep_out_desc = { 159 .bLength = USB_DT_ENDPOINT_SIZE, 160 .bDescriptorType = USB_DT_ENDPOINT, 161 .bmAttributes = USB_ENDPOINT_XFER_BULK, 162 .wMaxPacketSize = cpu_to_le16(512) 163}; 164 165static struct usb_descriptor_header *hs_printer_function[] = { 166 (struct usb_descriptor_header *) &intf_desc, 167 (struct usb_descriptor_header *) &hs_ep_in_desc, 168 (struct usb_descriptor_header *) &hs_ep_out_desc, 169 NULL 170}; 171 172/* 173 * Added endpoint descriptors for 3.0 devices 174 */ 175 176static struct usb_endpoint_descriptor ss_ep_in_desc = { 177 .bLength = USB_DT_ENDPOINT_SIZE, 178 .bDescriptorType = USB_DT_ENDPOINT, 179 .bmAttributes = USB_ENDPOINT_XFER_BULK, 180 .wMaxPacketSize = cpu_to_le16(1024), 181}; 182 183static struct usb_ss_ep_comp_descriptor ss_ep_in_comp_desc = { 184 .bLength = sizeof(ss_ep_in_comp_desc), 185 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP, 186}; 187 188static struct usb_endpoint_descriptor ss_ep_out_desc = { 189 .bLength = USB_DT_ENDPOINT_SIZE, 190 .bDescriptorType = USB_DT_ENDPOINT, 191 .bmAttributes = USB_ENDPOINT_XFER_BULK, 192 .wMaxPacketSize = cpu_to_le16(1024), 193}; 194 195static struct usb_ss_ep_comp_descriptor ss_ep_out_comp_desc = { 196 .bLength = sizeof(ss_ep_out_comp_desc), 197 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP, 198}; 199 200static struct usb_descriptor_header *ss_printer_function[] = { 201 (struct usb_descriptor_header *) &intf_desc, 202 (struct usb_descriptor_header *) &ss_ep_in_desc, 203 (struct usb_descriptor_header *) &ss_ep_in_comp_desc, 204 (struct usb_descriptor_header *) &ss_ep_out_desc, 205 (struct usb_descriptor_header *) &ss_ep_out_comp_desc, 206 NULL 207}; 208 209/* maxpacket and other transfer characteristics vary by speed. */ 210static inline struct usb_endpoint_descriptor *ep_desc(struct usb_gadget *gadget, 211 struct usb_endpoint_descriptor *fs, 212 struct usb_endpoint_descriptor *hs, 213 struct usb_endpoint_descriptor *ss) 214{ 215 switch (gadget->speed) { 216 case USB_SPEED_SUPER: 217 return ss; 218 case USB_SPEED_HIGH: 219 return hs; 220 default: 221 return fs; 222 } 223} 224 225/*-------------------------------------------------------------------------*/ 226 227static void printer_dev_free(struct kref *kref) 228{ 229 struct printer_dev *dev = container_of(kref, struct printer_dev, kref); 230 231 kfree(dev); 232} 233 234static struct usb_request * 235printer_req_alloc(struct usb_ep *ep, unsigned len, gfp_t gfp_flags) 236{ 237 struct usb_request *req; 238 239 req = usb_ep_alloc_request(ep, gfp_flags); 240 241 if (req != NULL) { 242 req->length = len; 243 req->buf = kmalloc(len, gfp_flags); 244 if (req->buf == NULL) { 245 usb_ep_free_request(ep, req); 246 return NULL; 247 } 248 } 249 250 return req; 251} 252 253static void 254printer_req_free(struct usb_ep *ep, struct usb_request *req) 255{ 256 if (ep != NULL && req != NULL) { 257 kfree(req->buf); 258 usb_ep_free_request(ep, req); 259 } 260} 261 262/*-------------------------------------------------------------------------*/ 263 264static void rx_complete(struct usb_ep *ep, struct usb_request *req) 265{ 266 struct printer_dev *dev = ep->driver_data; 267 int status = req->status; 268 unsigned long flags; 269 270 spin_lock_irqsave(&dev->lock, flags); 271 272 list_del_init(&req->list); /* Remode from Active List */ 273 274 switch (status) { 275 276 /* normal completion */ 277 case 0: 278 if (req->actual > 0) { 279 list_add_tail(&req->list, &dev->rx_buffers); 280 DBG(dev, "G_Printer : rx length %d\n", req->actual); 281 } else { 282 list_add(&req->list, &dev->rx_reqs); 283 } 284 break; 285 286 /* software-driven interface shutdown */ 287 case -ECONNRESET: /* unlink */ 288 case -ESHUTDOWN: /* disconnect etc */ 289 VDBG(dev, "rx shutdown, code %d\n", status); 290 list_add(&req->list, &dev->rx_reqs); 291 break; 292 293 /* for hardware automagic (such as pxa) */ 294 case -ECONNABORTED: /* endpoint reset */ 295 DBG(dev, "rx %s reset\n", ep->name); 296 list_add(&req->list, &dev->rx_reqs); 297 break; 298 299 /* data overrun */ 300 case -EOVERFLOW: 301 fallthrough; 302 303 default: 304 DBG(dev, "rx status %d\n", status); 305 list_add(&req->list, &dev->rx_reqs); 306 break; 307 } 308 309 wake_up_interruptible(&dev->rx_wait); 310 spin_unlock_irqrestore(&dev->lock, flags); 311} 312 313static void tx_complete(struct usb_ep *ep, struct usb_request *req) 314{ 315 struct printer_dev *dev = ep->driver_data; 316 317 switch (req->status) { 318 default: 319 VDBG(dev, "tx err %d\n", req->status); 320 fallthrough; 321 case -ECONNRESET: /* unlink */ 322 case -ESHUTDOWN: /* disconnect etc */ 323 break; 324 case 0: 325 break; 326 } 327 328 spin_lock(&dev->lock); 329 /* Take the request struct off the active list and put it on the 330 * free list. 331 */ 332 list_del_init(&req->list); 333 list_add(&req->list, &dev->tx_reqs); 334 wake_up_interruptible(&dev->tx_wait); 335 if (likely(list_empty(&dev->tx_reqs_active))) 336 wake_up_interruptible(&dev->tx_flush_wait); 337 338 spin_unlock(&dev->lock); 339} 340 341/*-------------------------------------------------------------------------*/ 342 343static int 344printer_open(struct inode *inode, struct file *fd) 345{ 346 struct printer_dev *dev; 347 unsigned long flags; 348 int ret = -EBUSY; 349 350 dev = container_of(inode->i_cdev, struct printer_dev, printer_cdev); 351 352 spin_lock_irqsave(&dev->lock, flags); 353 354 if (dev->interface < 0) { 355 spin_unlock_irqrestore(&dev->lock, flags); 356 return -ENODEV; 357 } 358 359 if (!dev->printer_cdev_open) { 360 dev->printer_cdev_open = 1; 361 fd->private_data = dev; 362 ret = 0; 363 /* Change the printer status to show that it's on-line. */ 364 dev->printer_status |= PRINTER_SELECTED; 365 } 366 367 spin_unlock_irqrestore(&dev->lock, flags); 368 369 kref_get(&dev->kref); 370 371 return ret; 372} 373 374static int 375printer_close(struct inode *inode, struct file *fd) 376{ 377 struct printer_dev *dev = fd->private_data; 378 unsigned long flags; 379 380 spin_lock_irqsave(&dev->lock, flags); 381 dev->printer_cdev_open = 0; 382 fd->private_data = NULL; 383 /* Change printer status to show that the printer is off-line. */ 384 dev->printer_status &= ~PRINTER_SELECTED; 385 spin_unlock_irqrestore(&dev->lock, flags); 386 387 kref_put(&dev->kref, printer_dev_free); 388 389 return 0; 390} 391 392/* This function must be called with interrupts turned off. */ 393static void 394setup_rx_reqs(struct printer_dev *dev) 395{ 396 struct usb_request *req; 397 398 while (likely(!list_empty(&dev->rx_reqs))) { 399 int error; 400 401 req = container_of(dev->rx_reqs.next, 402 struct usb_request, list); 403 list_del_init(&req->list); 404 405 /* The USB Host sends us whatever amount of data it wants to 406 * so we always set the length field to the full USB_BUFSIZE. 407 * If the amount of data is more than the read() caller asked 408 * for it will be stored in the request buffer until it is 409 * asked for by read(). 410 */ 411 req->length = USB_BUFSIZE; 412 req->complete = rx_complete; 413 414 /* here, we unlock, and only unlock, to avoid deadlock. */ 415 spin_unlock(&dev->lock); 416 error = usb_ep_queue(dev->out_ep, req, GFP_ATOMIC); 417 spin_lock(&dev->lock); 418 if (error) { 419 DBG(dev, "rx submit --> %d\n", error); 420 list_add(&req->list, &dev->rx_reqs); 421 break; 422 } 423 /* if the req is empty, then add it into dev->rx_reqs_active. */ 424 else if (list_empty(&req->list)) 425 list_add(&req->list, &dev->rx_reqs_active); 426 } 427} 428 429static ssize_t 430printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr) 431{ 432 struct printer_dev *dev = fd->private_data; 433 unsigned long flags; 434 size_t size; 435 size_t bytes_copied; 436 struct usb_request *req; 437 /* This is a pointer to the current USB rx request. */ 438 struct usb_request *current_rx_req; 439 /* This is the number of bytes in the current rx buffer. */ 440 size_t current_rx_bytes; 441 /* This is a pointer to the current rx buffer. */ 442 u8 *current_rx_buf; 443 444 if (len == 0) 445 return -EINVAL; 446 447 DBG(dev, "printer_read trying to read %d bytes\n", (int)len); 448 449 mutex_lock(&dev->lock_printer_io); 450 spin_lock_irqsave(&dev->lock, flags); 451 452 if (dev->interface < 0) { 453 spin_unlock_irqrestore(&dev->lock, flags); 454 mutex_unlock(&dev->lock_printer_io); 455 return -ENODEV; 456 } 457 458 /* We will use this flag later to check if a printer reset happened 459 * after we turn interrupts back on. 460 */ 461 dev->reset_printer = 0; 462 463 setup_rx_reqs(dev); 464 465 bytes_copied = 0; 466 current_rx_req = dev->current_rx_req; 467 current_rx_bytes = dev->current_rx_bytes; 468 current_rx_buf = dev->current_rx_buf; 469 dev->current_rx_req = NULL; 470 dev->current_rx_bytes = 0; 471 dev->current_rx_buf = NULL; 472 473 /* Check if there is any data in the read buffers. Please note that 474 * current_rx_bytes is the number of bytes in the current rx buffer. 475 * If it is zero then check if there are any other rx_buffers that 476 * are on the completed list. We are only out of data if all rx 477 * buffers are empty. 478 */ 479 if ((current_rx_bytes == 0) && 480 (likely(list_empty(&dev->rx_buffers)))) { 481 /* Turn interrupts back on before sleeping. */ 482 spin_unlock_irqrestore(&dev->lock, flags); 483 484 /* 485 * If no data is available check if this is a NON-Blocking 486 * call or not. 487 */ 488 if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) { 489 mutex_unlock(&dev->lock_printer_io); 490 return -EAGAIN; 491 } 492 493 /* Sleep until data is available */ 494 wait_event_interruptible(dev->rx_wait, 495 (likely(!list_empty(&dev->rx_buffers)))); 496 spin_lock_irqsave(&dev->lock, flags); 497 } 498 499 /* We have data to return then copy it to the caller's buffer.*/ 500 while ((current_rx_bytes || likely(!list_empty(&dev->rx_buffers))) 501 && len) { 502 if (current_rx_bytes == 0) { 503 req = container_of(dev->rx_buffers.next, 504 struct usb_request, list); 505 list_del_init(&req->list); 506 507 if (req->actual && req->buf) { 508 current_rx_req = req; 509 current_rx_bytes = req->actual; 510 current_rx_buf = req->buf; 511 } else { 512 list_add(&req->list, &dev->rx_reqs); 513 continue; 514 } 515 } 516 517 /* Don't leave irqs off while doing memory copies */ 518 spin_unlock_irqrestore(&dev->lock, flags); 519 520 if (len > current_rx_bytes) 521 size = current_rx_bytes; 522 else 523 size = len; 524 525 size -= copy_to_user(buf, current_rx_buf, size); 526 bytes_copied += size; 527 len -= size; 528 buf += size; 529 530 spin_lock_irqsave(&dev->lock, flags); 531 532 /* We've disconnected or reset so return. */ 533 if (dev->reset_printer) { 534 list_add(¤t_rx_req->list, &dev->rx_reqs); 535 spin_unlock_irqrestore(&dev->lock, flags); 536 mutex_unlock(&dev->lock_printer_io); 537 return -EAGAIN; 538 } 539 540 /* If we not returning all the data left in this RX request 541 * buffer then adjust the amount of data left in the buffer. 542 * Othewise if we are done with this RX request buffer then 543 * requeue it to get any incoming data from the USB host. 544 */ 545 if (size < current_rx_bytes) { 546 current_rx_bytes -= size; 547 current_rx_buf += size; 548 } else { 549 list_add(¤t_rx_req->list, &dev->rx_reqs); 550 current_rx_bytes = 0; 551 current_rx_buf = NULL; 552 current_rx_req = NULL; 553 } 554 } 555 556 dev->current_rx_req = current_rx_req; 557 dev->current_rx_bytes = current_rx_bytes; 558 dev->current_rx_buf = current_rx_buf; 559 560 spin_unlock_irqrestore(&dev->lock, flags); 561 mutex_unlock(&dev->lock_printer_io); 562 563 DBG(dev, "printer_read returned %d bytes\n", (int)bytes_copied); 564 565 if (bytes_copied) 566 return bytes_copied; 567 else 568 return -EAGAIN; 569} 570 571static ssize_t 572printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr) 573{ 574 struct printer_dev *dev = fd->private_data; 575 unsigned long flags; 576 size_t size; /* Amount of data in a TX request. */ 577 size_t bytes_copied = 0; 578 struct usb_request *req; 579 int value; 580 581 DBG(dev, "printer_write trying to send %d bytes\n", (int)len); 582 583 if (len == 0) 584 return -EINVAL; 585 586 mutex_lock(&dev->lock_printer_io); 587 spin_lock_irqsave(&dev->lock, flags); 588 589 if (dev->interface < 0) { 590 spin_unlock_irqrestore(&dev->lock, flags); 591 mutex_unlock(&dev->lock_printer_io); 592 return -ENODEV; 593 } 594 595 /* Check if a printer reset happens while we have interrupts on */ 596 dev->reset_printer = 0; 597 598 /* Check if there is any available write buffers */ 599 if (likely(list_empty(&dev->tx_reqs))) { 600 /* Turn interrupts back on before sleeping. */ 601 spin_unlock_irqrestore(&dev->lock, flags); 602 603 /* 604 * If write buffers are available check if this is 605 * a NON-Blocking call or not. 606 */ 607 if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) { 608 mutex_unlock(&dev->lock_printer_io); 609 return -EAGAIN; 610 } 611 612 /* Sleep until a write buffer is available */ 613 wait_event_interruptible(dev->tx_wait, 614 (likely(!list_empty(&dev->tx_reqs)))); 615 spin_lock_irqsave(&dev->lock, flags); 616 } 617 618 while (likely(!list_empty(&dev->tx_reqs)) && len) { 619 620 if (len > USB_BUFSIZE) 621 size = USB_BUFSIZE; 622 else 623 size = len; 624 625 req = container_of(dev->tx_reqs.next, struct usb_request, 626 list); 627 list_del_init(&req->list); 628 629 req->complete = tx_complete; 630 req->length = size; 631 632 /* Check if we need to send a zero length packet. */ 633 if (len > size) 634 /* They will be more TX requests so no yet. */ 635 req->zero = 0; 636 else 637 /* If the data amount is not a multiple of the 638 * maxpacket size then send a zero length packet. 639 */ 640 req->zero = ((len % dev->in_ep->maxpacket) == 0); 641 642 /* Don't leave irqs off while doing memory copies */ 643 spin_unlock_irqrestore(&dev->lock, flags); 644 645 if (copy_from_user(req->buf, buf, size)) { 646 list_add(&req->list, &dev->tx_reqs); 647 mutex_unlock(&dev->lock_printer_io); 648 return bytes_copied; 649 } 650 651 bytes_copied += size; 652 len -= size; 653 buf += size; 654 655 spin_lock_irqsave(&dev->lock, flags); 656 657 /* We've disconnected or reset so free the req and buffer */ 658 if (dev->reset_printer) { 659 list_add(&req->list, &dev->tx_reqs); 660 spin_unlock_irqrestore(&dev->lock, flags); 661 mutex_unlock(&dev->lock_printer_io); 662 return -EAGAIN; 663 } 664 665 list_add(&req->list, &dev->tx_reqs_active); 666 667 /* here, we unlock, and only unlock, to avoid deadlock. */ 668 spin_unlock(&dev->lock); 669 value = usb_ep_queue(dev->in_ep, req, GFP_ATOMIC); 670 spin_lock(&dev->lock); 671 if (value) { 672 list_move(&req->list, &dev->tx_reqs); 673 spin_unlock_irqrestore(&dev->lock, flags); 674 mutex_unlock(&dev->lock_printer_io); 675 return -EAGAIN; 676 } 677 } 678 679 spin_unlock_irqrestore(&dev->lock, flags); 680 mutex_unlock(&dev->lock_printer_io); 681 682 DBG(dev, "printer_write sent %d bytes\n", (int)bytes_copied); 683 684 if (bytes_copied) 685 return bytes_copied; 686 else 687 return -EAGAIN; 688} 689 690static int 691printer_fsync(struct file *fd, loff_t start, loff_t end, int datasync) 692{ 693 struct printer_dev *dev = fd->private_data; 694 struct inode *inode = file_inode(fd); 695 unsigned long flags; 696 int tx_list_empty; 697 698 inode_lock(inode); 699 spin_lock_irqsave(&dev->lock, flags); 700 701 if (dev->interface < 0) { 702 spin_unlock_irqrestore(&dev->lock, flags); 703 inode_unlock(inode); 704 return -ENODEV; 705 } 706 707 tx_list_empty = (likely(list_empty(&dev->tx_reqs))); 708 spin_unlock_irqrestore(&dev->lock, flags); 709 710 if (!tx_list_empty) { 711 /* Sleep until all data has been sent */ 712 wait_event_interruptible(dev->tx_flush_wait, 713 (likely(list_empty(&dev->tx_reqs_active)))); 714 } 715 inode_unlock(inode); 716 717 return 0; 718} 719 720static __poll_t 721printer_poll(struct file *fd, poll_table *wait) 722{ 723 struct printer_dev *dev = fd->private_data; 724 unsigned long flags; 725 __poll_t status = 0; 726 727 mutex_lock(&dev->lock_printer_io); 728 spin_lock_irqsave(&dev->lock, flags); 729 730 if (dev->interface < 0) { 731 spin_unlock_irqrestore(&dev->lock, flags); 732 mutex_unlock(&dev->lock_printer_io); 733 return EPOLLERR | EPOLLHUP; 734 } 735 736 setup_rx_reqs(dev); 737 spin_unlock_irqrestore(&dev->lock, flags); 738 mutex_unlock(&dev->lock_printer_io); 739 740 poll_wait(fd, &dev->rx_wait, wait); 741 poll_wait(fd, &dev->tx_wait, wait); 742 743 spin_lock_irqsave(&dev->lock, flags); 744 if (likely(!list_empty(&dev->tx_reqs))) 745 status |= EPOLLOUT | EPOLLWRNORM; 746 747 if (likely(dev->current_rx_bytes) || 748 likely(!list_empty(&dev->rx_buffers))) 749 status |= EPOLLIN | EPOLLRDNORM; 750 751 spin_unlock_irqrestore(&dev->lock, flags); 752 753 return status; 754} 755 756static long 757printer_ioctl(struct file *fd, unsigned int code, unsigned long arg) 758{ 759 struct printer_dev *dev = fd->private_data; 760 unsigned long flags; 761 int status = 0; 762 763 DBG(dev, "printer_ioctl: cmd=0x%4.4x, arg=%lu\n", code, arg); 764 765 /* handle ioctls */ 766 767 spin_lock_irqsave(&dev->lock, flags); 768 769 if (dev->interface < 0) { 770 spin_unlock_irqrestore(&dev->lock, flags); 771 return -ENODEV; 772 } 773 774 switch (code) { 775 case GADGET_GET_PRINTER_STATUS: 776 status = (int)dev->printer_status; 777 break; 778 case GADGET_SET_PRINTER_STATUS: 779 dev->printer_status = (u8)arg; 780 break; 781 default: 782 /* could not handle ioctl */ 783 DBG(dev, "printer_ioctl: ERROR cmd=0x%4.4xis not supported\n", 784 code); 785 status = -ENOTTY; 786 } 787 788 spin_unlock_irqrestore(&dev->lock, flags); 789 790 return status; 791} 792 793/* used after endpoint configuration */ 794static const struct file_operations printer_io_operations = { 795 .owner = THIS_MODULE, 796 .open = printer_open, 797 .read = printer_read, 798 .write = printer_write, 799 .fsync = printer_fsync, 800 .poll = printer_poll, 801 .unlocked_ioctl = printer_ioctl, 802 .release = printer_close, 803 .llseek = noop_llseek, 804}; 805 806/*-------------------------------------------------------------------------*/ 807 808static int 809set_printer_interface(struct printer_dev *dev) 810{ 811 int result = 0; 812 813 dev->in_ep->desc = ep_desc(dev->gadget, &fs_ep_in_desc, &hs_ep_in_desc, 814 &ss_ep_in_desc); 815 dev->in_ep->driver_data = dev; 816 817 dev->out_ep->desc = ep_desc(dev->gadget, &fs_ep_out_desc, 818 &hs_ep_out_desc, &ss_ep_out_desc); 819 dev->out_ep->driver_data = dev; 820 821 result = usb_ep_enable(dev->in_ep); 822 if (result != 0) { 823 DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result); 824 goto done; 825 } 826 827 result = usb_ep_enable(dev->out_ep); 828 if (result != 0) { 829 DBG(dev, "enable %s --> %d\n", dev->out_ep->name, result); 830 goto done; 831 } 832 833done: 834 /* on error, disable any endpoints */ 835 if (result != 0) { 836 (void) usb_ep_disable(dev->in_ep); 837 (void) usb_ep_disable(dev->out_ep); 838 dev->in_ep->desc = NULL; 839 dev->out_ep->desc = NULL; 840 } 841 842 /* caller is responsible for cleanup on error */ 843 return result; 844} 845 846static void printer_reset_interface(struct printer_dev *dev) 847{ 848 unsigned long flags; 849 850 if (dev->interface < 0) 851 return; 852 853 if (dev->in_ep->desc) 854 usb_ep_disable(dev->in_ep); 855 856 if (dev->out_ep->desc) 857 usb_ep_disable(dev->out_ep); 858 859 spin_lock_irqsave(&dev->lock, flags); 860 dev->in_ep->desc = NULL; 861 dev->out_ep->desc = NULL; 862 dev->interface = -1; 863 spin_unlock_irqrestore(&dev->lock, flags); 864} 865 866/* Change our operational Interface. */ 867static int set_interface(struct printer_dev *dev, unsigned number) 868{ 869 int result = 0; 870 871 /* Free the current interface */ 872 printer_reset_interface(dev); 873 874 result = set_printer_interface(dev); 875 if (result) 876 printer_reset_interface(dev); 877 else 878 dev->interface = number; 879 880 if (!result) 881 INFO(dev, "Using interface %x\n", number); 882 883 return result; 884} 885 886static void printer_soft_reset(struct printer_dev *dev) 887{ 888 struct usb_request *req; 889 890 if (usb_ep_disable(dev->in_ep)) 891 DBG(dev, "Failed to disable USB in_ep\n"); 892 if (usb_ep_disable(dev->out_ep)) 893 DBG(dev, "Failed to disable USB out_ep\n"); 894 895 if (dev->current_rx_req != NULL) { 896 list_add(&dev->current_rx_req->list, &dev->rx_reqs); 897 dev->current_rx_req = NULL; 898 } 899 dev->current_rx_bytes = 0; 900 dev->current_rx_buf = NULL; 901 dev->reset_printer = 1; 902 903 while (likely(!(list_empty(&dev->rx_buffers)))) { 904 req = container_of(dev->rx_buffers.next, struct usb_request, 905 list); 906 list_del_init(&req->list); 907 list_add(&req->list, &dev->rx_reqs); 908 } 909 910 while (likely(!(list_empty(&dev->rx_reqs_active)))) { 911 req = container_of(dev->rx_buffers.next, struct usb_request, 912 list); 913 list_del_init(&req->list); 914 list_add(&req->list, &dev->rx_reqs); 915 } 916 917 while (likely(!(list_empty(&dev->tx_reqs_active)))) { 918 req = container_of(dev->tx_reqs_active.next, 919 struct usb_request, list); 920 list_del_init(&req->list); 921 list_add(&req->list, &dev->tx_reqs); 922 } 923 924 if (usb_ep_enable(dev->in_ep)) 925 DBG(dev, "Failed to enable USB in_ep\n"); 926 if (usb_ep_enable(dev->out_ep)) 927 DBG(dev, "Failed to enable USB out_ep\n"); 928 929 wake_up_interruptible(&dev->rx_wait); 930 wake_up_interruptible(&dev->tx_wait); 931 wake_up_interruptible(&dev->tx_flush_wait); 932} 933 934/*-------------------------------------------------------------------------*/ 935 936static bool gprinter_req_match(struct usb_function *f, 937 const struct usb_ctrlrequest *ctrl, 938 bool config0) 939{ 940 struct printer_dev *dev = func_to_printer(f); 941 u16 w_index = le16_to_cpu(ctrl->wIndex); 942 u16 w_value = le16_to_cpu(ctrl->wValue); 943 u16 w_length = le16_to_cpu(ctrl->wLength); 944 945 if (config0) 946 return false; 947 948 if ((ctrl->bRequestType & USB_RECIP_MASK) != USB_RECIP_INTERFACE || 949 (ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS) 950 return false; 951 952 switch (ctrl->bRequest) { 953 case GET_DEVICE_ID: 954 w_index >>= 8; 955 if (USB_DIR_IN & ctrl->bRequestType) 956 break; 957 return false; 958 case GET_PORT_STATUS: 959 if (!w_value && w_length == 1 && 960 (USB_DIR_IN & ctrl->bRequestType)) 961 break; 962 return false; 963 case SOFT_RESET: 964 if (!w_value && !w_length && 965 !(USB_DIR_IN & ctrl->bRequestType)) 966 break; 967 fallthrough; 968 default: 969 return false; 970 } 971 return w_index == dev->interface; 972} 973 974/* 975 * The setup() callback implements all the ep0 functionality that's not 976 * handled lower down. 977 */ 978static int printer_func_setup(struct usb_function *f, 979 const struct usb_ctrlrequest *ctrl) 980{ 981 struct printer_dev *dev = func_to_printer(f); 982 struct usb_composite_dev *cdev = f->config->cdev; 983 struct usb_request *req = cdev->req; 984 u8 *buf = req->buf; 985 int value = -EOPNOTSUPP; 986 u16 wIndex = le16_to_cpu(ctrl->wIndex); 987 u16 wValue = le16_to_cpu(ctrl->wValue); 988 u16 wLength = le16_to_cpu(ctrl->wLength); 989 990 DBG(dev, "ctrl req%02x.%02x v%04x i%04x l%d\n", 991 ctrl->bRequestType, ctrl->bRequest, wValue, wIndex, wLength); 992 993 switch (ctrl->bRequestType&USB_TYPE_MASK) { 994 case USB_TYPE_CLASS: 995 switch (ctrl->bRequest) { 996 case GET_DEVICE_ID: /* Get the IEEE-1284 PNP String */ 997 /* Only one printer interface is supported. */ 998 if ((wIndex>>8) != dev->interface) 999 break; 1000 1001 if (!*dev->pnp_string) { 1002 value = 0; 1003 break; 1004 } 1005 value = strlen(*dev->pnp_string); 1006 buf[0] = (value >> 8) & 0xFF; 1007 buf[1] = value & 0xFF; 1008 memcpy(buf + 2, *dev->pnp_string, value); 1009 DBG(dev, "1284 PNP String: %x %s\n", value, 1010 *dev->pnp_string); 1011 break; 1012 1013 case GET_PORT_STATUS: /* Get Port Status */ 1014 /* Only one printer interface is supported. */ 1015 if (wIndex != dev->interface) 1016 break; 1017 1018 buf[0] = dev->printer_status; 1019 value = min_t(u16, wLength, 1); 1020 break; 1021 1022 case SOFT_RESET: /* Soft Reset */ 1023 /* Only one printer interface is supported. */ 1024 if (wIndex != dev->interface) 1025 break; 1026 1027 printer_soft_reset(dev); 1028 1029 value = 0; 1030 break; 1031 1032 default: 1033 goto unknown; 1034 } 1035 break; 1036 1037 default: 1038unknown: 1039 VDBG(dev, 1040 "unknown ctrl req%02x.%02x v%04x i%04x l%d\n", 1041 ctrl->bRequestType, ctrl->bRequest, 1042 wValue, wIndex, wLength); 1043 break; 1044 } 1045 /* host either stalls (value < 0) or reports success */ 1046 if (value >= 0) { 1047 req->length = value; 1048 req->zero = value < wLength; 1049 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC); 1050 if (value < 0) { 1051 ERROR(dev, "%s:%d Error!\n", __func__, __LINE__); 1052 req->status = 0; 1053 } 1054 } 1055 return value; 1056} 1057 1058static int printer_func_bind(struct usb_configuration *c, 1059 struct usb_function *f) 1060{ 1061 struct usb_gadget *gadget = c->cdev->gadget; 1062 struct printer_dev *dev = func_to_printer(f); 1063 struct device *pdev; 1064 struct usb_composite_dev *cdev = c->cdev; 1065 struct usb_ep *in_ep; 1066 struct usb_ep *out_ep = NULL; 1067 struct usb_request *req; 1068 dev_t devt; 1069 int id; 1070 int ret; 1071 u32 i; 1072 1073 id = usb_interface_id(c, f); 1074 if (id < 0) 1075 return id; 1076 intf_desc.bInterfaceNumber = id; 1077 1078 /* finish hookup to lower layer ... */ 1079 dev->gadget = gadget; 1080 1081 /* all we really need is bulk IN/OUT */ 1082 in_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_in_desc); 1083 if (!in_ep) { 1084autoconf_fail: 1085 dev_err(&cdev->gadget->dev, "can't autoconfigure on %s\n", 1086 cdev->gadget->name); 1087 return -ENODEV; 1088 } 1089 1090 out_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_out_desc); 1091 if (!out_ep) 1092 goto autoconf_fail; 1093 1094 /* assumes that all endpoints are dual-speed */ 1095 hs_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress; 1096 hs_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress; 1097 ss_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress; 1098 ss_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress; 1099 1100 ret = usb_assign_descriptors(f, fs_printer_function, 1101 hs_printer_function, ss_printer_function, 1102 ss_printer_function); 1103 if (ret) 1104 return ret; 1105 1106 dev->in_ep = in_ep; 1107 dev->out_ep = out_ep; 1108 1109 ret = -ENOMEM; 1110 for (i = 0; i < dev->q_len; i++) { 1111 req = printer_req_alloc(dev->in_ep, USB_BUFSIZE, GFP_KERNEL); 1112 if (!req) 1113 goto fail_tx_reqs; 1114 list_add(&req->list, &dev->tx_reqs); 1115 } 1116 1117 for (i = 0; i < dev->q_len; i++) { 1118 req = printer_req_alloc(dev->out_ep, USB_BUFSIZE, GFP_KERNEL); 1119 if (!req) 1120 goto fail_rx_reqs; 1121 list_add(&req->list, &dev->rx_reqs); 1122 } 1123 1124 /* Setup the sysfs files for the printer gadget. */ 1125 devt = MKDEV(major, dev->minor); 1126 pdev = device_create(&usb_gadget_class, NULL, devt, 1127 NULL, "g_printer%d", dev->minor); 1128 if (IS_ERR(pdev)) { 1129 ERROR(dev, "Failed to create device: g_printer\n"); 1130 ret = PTR_ERR(pdev); 1131 goto fail_rx_reqs; 1132 } 1133 1134 /* 1135 * Register a character device as an interface to a user mode 1136 * program that handles the printer specific functionality. 1137 */ 1138 cdev_init(&dev->printer_cdev, &printer_io_operations); 1139 dev->printer_cdev.owner = THIS_MODULE; 1140 ret = cdev_add(&dev->printer_cdev, devt, 1); 1141 if (ret) { 1142 ERROR(dev, "Failed to open char device\n"); 1143 goto fail_cdev_add; 1144 } 1145 1146 return 0; 1147 1148fail_cdev_add: 1149 device_destroy(&usb_gadget_class, devt); 1150 1151fail_rx_reqs: 1152 while (!list_empty(&dev->rx_reqs)) { 1153 req = container_of(dev->rx_reqs.next, struct usb_request, list); 1154 list_del(&req->list); 1155 printer_req_free(dev->out_ep, req); 1156 } 1157 1158fail_tx_reqs: 1159 while (!list_empty(&dev->tx_reqs)) { 1160 req = container_of(dev->tx_reqs.next, struct usb_request, list); 1161 list_del(&req->list); 1162 printer_req_free(dev->in_ep, req); 1163 } 1164 1165 usb_free_all_descriptors(f); 1166 return ret; 1167 1168} 1169 1170static int printer_func_set_alt(struct usb_function *f, 1171 unsigned intf, unsigned alt) 1172{ 1173 struct printer_dev *dev = func_to_printer(f); 1174 int ret = -ENOTSUPP; 1175 1176 if (!alt) 1177 ret = set_interface(dev, intf); 1178 1179 return ret; 1180} 1181 1182static void printer_func_disable(struct usb_function *f) 1183{ 1184 struct printer_dev *dev = func_to_printer(f); 1185 1186 printer_reset_interface(dev); 1187} 1188 1189static inline struct f_printer_opts 1190*to_f_printer_opts(struct config_item *item) 1191{ 1192 return container_of(to_config_group(item), struct f_printer_opts, 1193 func_inst.group); 1194} 1195 1196static void printer_attr_release(struct config_item *item) 1197{ 1198 struct f_printer_opts *opts = to_f_printer_opts(item); 1199 1200 usb_put_function_instance(&opts->func_inst); 1201} 1202 1203static struct configfs_item_operations printer_item_ops = { 1204 .release = printer_attr_release, 1205}; 1206 1207static ssize_t f_printer_opts_pnp_string_show(struct config_item *item, 1208 char *page) 1209{ 1210 struct f_printer_opts *opts = to_f_printer_opts(item); 1211 int result = 0; 1212 1213 mutex_lock(&opts->lock); 1214 if (!opts->pnp_string) 1215 goto unlock; 1216 1217 result = strscpy(page, opts->pnp_string, PAGE_SIZE); 1218 if (result < 1) { 1219 result = PAGE_SIZE; 1220 } else if (page[result - 1] != '\n' && result + 1 < PAGE_SIZE) { 1221 page[result++] = '\n'; 1222 page[result] = '\0'; 1223 } 1224 1225unlock: 1226 mutex_unlock(&opts->lock); 1227 1228 return result; 1229} 1230 1231static ssize_t f_printer_opts_pnp_string_store(struct config_item *item, 1232 const char *page, size_t len) 1233{ 1234 struct f_printer_opts *opts = to_f_printer_opts(item); 1235 char *new_pnp; 1236 int result; 1237 1238 mutex_lock(&opts->lock); 1239 1240 new_pnp = kstrndup(page, len, GFP_KERNEL); 1241 if (!new_pnp) { 1242 result = -ENOMEM; 1243 goto unlock; 1244 } 1245 1246 if (opts->pnp_string_allocated) 1247 kfree(opts->pnp_string); 1248 1249 opts->pnp_string_allocated = true; 1250 opts->pnp_string = new_pnp; 1251 result = len; 1252unlock: 1253 mutex_unlock(&opts->lock); 1254 1255 return result; 1256} 1257 1258CONFIGFS_ATTR(f_printer_opts_, pnp_string); 1259 1260static ssize_t f_printer_opts_q_len_show(struct config_item *item, 1261 char *page) 1262{ 1263 struct f_printer_opts *opts = to_f_printer_opts(item); 1264 int result; 1265 1266 mutex_lock(&opts->lock); 1267 result = sprintf(page, "%d\n", opts->q_len); 1268 mutex_unlock(&opts->lock); 1269 1270 return result; 1271} 1272 1273static ssize_t f_printer_opts_q_len_store(struct config_item *item, 1274 const char *page, size_t len) 1275{ 1276 struct f_printer_opts *opts = to_f_printer_opts(item); 1277 int ret; 1278 u16 num; 1279 1280 mutex_lock(&opts->lock); 1281 if (opts->refcnt) { 1282 ret = -EBUSY; 1283 goto end; 1284 } 1285 1286 ret = kstrtou16(page, 0, &num); 1287 if (ret) 1288 goto end; 1289 1290 opts->q_len = (unsigned)num; 1291 ret = len; 1292end: 1293 mutex_unlock(&opts->lock); 1294 return ret; 1295} 1296 1297CONFIGFS_ATTR(f_printer_opts_, q_len); 1298 1299static struct configfs_attribute *printer_attrs[] = { 1300 &f_printer_opts_attr_pnp_string, 1301 &f_printer_opts_attr_q_len, 1302 NULL, 1303}; 1304 1305static const struct config_item_type printer_func_type = { 1306 .ct_item_ops = &printer_item_ops, 1307 .ct_attrs = printer_attrs, 1308 .ct_owner = THIS_MODULE, 1309}; 1310 1311static inline int gprinter_get_minor(void) 1312{ 1313 int ret; 1314 1315 ret = ida_simple_get(&printer_ida, 0, 0, GFP_KERNEL); 1316 if (ret >= PRINTER_MINORS) { 1317 ida_simple_remove(&printer_ida, ret); 1318 ret = -ENODEV; 1319 } 1320 1321 return ret; 1322} 1323 1324static inline void gprinter_put_minor(int minor) 1325{ 1326 ida_simple_remove(&printer_ida, minor); 1327} 1328 1329static int gprinter_setup(int); 1330static void gprinter_cleanup(void); 1331 1332static void gprinter_free_inst(struct usb_function_instance *f) 1333{ 1334 struct f_printer_opts *opts; 1335 1336 opts = container_of(f, struct f_printer_opts, func_inst); 1337 1338 mutex_lock(&printer_ida_lock); 1339 1340 gprinter_put_minor(opts->minor); 1341 if (ida_is_empty(&printer_ida)) 1342 gprinter_cleanup(); 1343 1344 mutex_unlock(&printer_ida_lock); 1345 1346 if (opts->pnp_string_allocated) 1347 kfree(opts->pnp_string); 1348 kfree(opts); 1349} 1350 1351static struct usb_function_instance *gprinter_alloc_inst(void) 1352{ 1353 struct f_printer_opts *opts; 1354 struct usb_function_instance *ret; 1355 int status = 0; 1356 1357 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 1358 if (!opts) 1359 return ERR_PTR(-ENOMEM); 1360 1361 mutex_init(&opts->lock); 1362 opts->func_inst.free_func_inst = gprinter_free_inst; 1363 ret = &opts->func_inst; 1364 1365 /* Make sure q_len is initialized, otherwise the bound device can't support read/write! */ 1366 opts->q_len = DEFAULT_Q_LEN; 1367 1368 mutex_lock(&printer_ida_lock); 1369 1370 if (ida_is_empty(&printer_ida)) { 1371 status = gprinter_setup(PRINTER_MINORS); 1372 if (status) { 1373 ret = ERR_PTR(status); 1374 kfree(opts); 1375 goto unlock; 1376 } 1377 } 1378 1379 opts->minor = gprinter_get_minor(); 1380 if (opts->minor < 0) { 1381 ret = ERR_PTR(opts->minor); 1382 kfree(opts); 1383 if (ida_is_empty(&printer_ida)) 1384 gprinter_cleanup(); 1385 goto unlock; 1386 } 1387 config_group_init_type_name(&opts->func_inst.group, "", 1388 &printer_func_type); 1389 1390unlock: 1391 mutex_unlock(&printer_ida_lock); 1392 return ret; 1393} 1394 1395static void gprinter_free(struct usb_function *f) 1396{ 1397 struct printer_dev *dev = func_to_printer(f); 1398 struct f_printer_opts *opts; 1399 1400 opts = container_of(f->fi, struct f_printer_opts, func_inst); 1401 1402 kref_put(&dev->kref, printer_dev_free); 1403 mutex_lock(&opts->lock); 1404 --opts->refcnt; 1405 mutex_unlock(&opts->lock); 1406} 1407 1408static void printer_func_unbind(struct usb_configuration *c, 1409 struct usb_function *f) 1410{ 1411 struct printer_dev *dev; 1412 struct usb_request *req; 1413 1414 dev = func_to_printer(f); 1415 1416 device_destroy(&usb_gadget_class, MKDEV(major, dev->minor)); 1417 1418 /* Remove Character Device */ 1419 cdev_del(&dev->printer_cdev); 1420 1421 /* we must already have been disconnected ... no i/o may be active */ 1422 WARN_ON(!list_empty(&dev->tx_reqs_active)); 1423 WARN_ON(!list_empty(&dev->rx_reqs_active)); 1424 1425 /* Free all memory for this driver. */ 1426 while (!list_empty(&dev->tx_reqs)) { 1427 req = container_of(dev->tx_reqs.next, struct usb_request, 1428 list); 1429 list_del(&req->list); 1430 printer_req_free(dev->in_ep, req); 1431 } 1432 1433 if (dev->current_rx_req != NULL) 1434 printer_req_free(dev->out_ep, dev->current_rx_req); 1435 1436 while (!list_empty(&dev->rx_reqs)) { 1437 req = container_of(dev->rx_reqs.next, 1438 struct usb_request, list); 1439 list_del(&req->list); 1440 printer_req_free(dev->out_ep, req); 1441 } 1442 1443 while (!list_empty(&dev->rx_buffers)) { 1444 req = container_of(dev->rx_buffers.next, 1445 struct usb_request, list); 1446 list_del(&req->list); 1447 printer_req_free(dev->out_ep, req); 1448 } 1449 usb_free_all_descriptors(f); 1450} 1451 1452static struct usb_function *gprinter_alloc(struct usb_function_instance *fi) 1453{ 1454 struct printer_dev *dev; 1455 struct f_printer_opts *opts; 1456 1457 opts = container_of(fi, struct f_printer_opts, func_inst); 1458 1459 mutex_lock(&opts->lock); 1460 if (opts->minor >= minors) { 1461 mutex_unlock(&opts->lock); 1462 return ERR_PTR(-ENOENT); 1463 } 1464 1465 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 1466 if (!dev) { 1467 mutex_unlock(&opts->lock); 1468 return ERR_PTR(-ENOMEM); 1469 } 1470 1471 kref_init(&dev->kref); 1472 ++opts->refcnt; 1473 dev->minor = opts->minor; 1474 dev->pnp_string = &opts->pnp_string; 1475 dev->q_len = opts->q_len; 1476 mutex_unlock(&opts->lock); 1477 1478 dev->function.name = "printer"; 1479 dev->function.bind = printer_func_bind; 1480 dev->function.setup = printer_func_setup; 1481 dev->function.unbind = printer_func_unbind; 1482 dev->function.set_alt = printer_func_set_alt; 1483 dev->function.disable = printer_func_disable; 1484 dev->function.req_match = gprinter_req_match; 1485 dev->function.free_func = gprinter_free; 1486 1487 INIT_LIST_HEAD(&dev->tx_reqs); 1488 INIT_LIST_HEAD(&dev->rx_reqs); 1489 INIT_LIST_HEAD(&dev->rx_buffers); 1490 INIT_LIST_HEAD(&dev->tx_reqs_active); 1491 INIT_LIST_HEAD(&dev->rx_reqs_active); 1492 1493 spin_lock_init(&dev->lock); 1494 mutex_init(&dev->lock_printer_io); 1495 init_waitqueue_head(&dev->rx_wait); 1496 init_waitqueue_head(&dev->tx_wait); 1497 init_waitqueue_head(&dev->tx_flush_wait); 1498 1499 dev->interface = -1; 1500 dev->printer_cdev_open = 0; 1501 dev->printer_status = PRINTER_NOT_ERROR; 1502 dev->current_rx_req = NULL; 1503 dev->current_rx_bytes = 0; 1504 dev->current_rx_buf = NULL; 1505 1506 return &dev->function; 1507} 1508 1509DECLARE_USB_FUNCTION_INIT(printer, gprinter_alloc_inst, gprinter_alloc); 1510MODULE_LICENSE("GPL"); 1511MODULE_AUTHOR("Craig Nadler"); 1512 1513static int gprinter_setup(int count) 1514{ 1515 int status; 1516 dev_t devt; 1517 1518 status = class_register(&usb_gadget_class); 1519 if (status) 1520 return status; 1521 1522 status = alloc_chrdev_region(&devt, 0, count, "USB printer gadget"); 1523 if (status) { 1524 pr_err("alloc_chrdev_region %d\n", status); 1525 class_unregister(&usb_gadget_class); 1526 return status; 1527 } 1528 1529 major = MAJOR(devt); 1530 minors = count; 1531 1532 return status; 1533} 1534 1535static void gprinter_cleanup(void) 1536{ 1537 if (major) { 1538 unregister_chrdev_region(MKDEV(major, 0), minors); 1539 major = minors = 0; 1540 } 1541 class_unregister(&usb_gadget_class); 1542} 1543