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treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / usb / gadget / function / f_printer.c
blob9c7ed2539ff7727c64427d76a681a063c82937b7
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
35 #include <asm/byteorder.h>
36 #include <linux/io.h>
37 #include <linux/irq.h>
38 #include <linux/uaccess.h>
39 #include <asm/unaligned.h>
40
41 #include <linux/usb/ch9.h>
42 #include <linux/usb/composite.h>
43 #include <linux/usb/gadget.h>
44 #include <linux/usb/g_printer.h>
45
46 #include "u_printer.h"
47
48 #define PRINTER_MINORS 4
49 #define GET_DEVICE_ID 0
50 #define GET_PORT_STATUS 1
51 #define SOFT_RESET 2
52
53 static int major, minors;
54 static struct class *usb_gadget_class;
55 static DEFINE_IDA(printer_ida);
56 static DEFINE_MUTEX(printer_ida_lock); /* protects access do printer_ida */
57
58 /*-------------------------------------------------------------------------*/
59
60 struct printer_dev {
61 spinlock_t lock; /* lock this structure */
62 /* lock buffer lists during read/write calls */
63 struct mutex lock_printer_io;
64 struct usb_gadget *gadget;
65 s8 interface;
66 struct usb_ep *in_ep, *out_ep;
67
68 struct list_head rx_reqs; /* List of free RX structs */
69 struct list_head rx_reqs_active; /* List of Active RX xfers */
70 struct list_head rx_buffers; /* List of completed xfers */
71 /* wait until there is data to be read. */
72 wait_queue_head_t rx_wait;
73 struct list_head tx_reqs; /* List of free TX structs */
74 struct list_head tx_reqs_active; /* List of Active TX xfers */
75 /* Wait until there are write buffers available to use. */
76 wait_queue_head_t tx_wait;
77 /* Wait until all write buffers have been sent. */
78 wait_queue_head_t tx_flush_wait;
79 struct usb_request *current_rx_req;
80 size_t current_rx_bytes;
81 u8 *current_rx_buf;
82 u8 printer_status;
83 u8 reset_printer;
84 int minor;
85 struct cdev printer_cdev;
86 u8 printer_cdev_open;
87 wait_queue_head_t wait;
88 unsigned q_len;
89 char *pnp_string; /* We don't own memory! */
90 struct usb_function function;
91 };
92
93 static inline struct printer_dev *func_to_printer(struct usb_function *f)
94 {
95 return container_of(f, struct printer_dev, function);
96 }
97
98 /*-------------------------------------------------------------------------*/
99
100 /*
101 * DESCRIPTORS ... most are static, but strings and (full) configuration
102 * descriptors are built on demand.
103 */
104
105 /* holds our biggest descriptor */
106 #define USB_DESC_BUFSIZE 256
107 #define USB_BUFSIZE 8192
108
109 static struct usb_interface_descriptor intf_desc = {
110 .bLength = sizeof(intf_desc),
111 .bDescriptorType = USB_DT_INTERFACE,
112 .bNumEndpoints = 2,
113 .bInterfaceClass = USB_CLASS_PRINTER,
114 .bInterfaceSubClass = 1, /* Printer Sub-Class */
115 .bInterfaceProtocol = 2, /* Bi-Directional */
116 .iInterface = 0
117 };
118
119 static struct usb_endpoint_descriptor fs_ep_in_desc = {
120 .bLength = USB_DT_ENDPOINT_SIZE,
121 .bDescriptorType = USB_DT_ENDPOINT,
122 .bEndpointAddress = USB_DIR_IN,
123 .bmAttributes = USB_ENDPOINT_XFER_BULK
124 };
125
126 static struct usb_endpoint_descriptor fs_ep_out_desc = {
127 .bLength = USB_DT_ENDPOINT_SIZE,
128 .bDescriptorType = USB_DT_ENDPOINT,
129 .bEndpointAddress = USB_DIR_OUT,
130 .bmAttributes = USB_ENDPOINT_XFER_BULK
131 };
132
133 static struct usb_descriptor_header *fs_printer_function[] = {
134 (struct usb_descriptor_header *) &intf_desc,
135 (struct usb_descriptor_header *) &fs_ep_in_desc,
136 (struct usb_descriptor_header *) &fs_ep_out_desc,
137 NULL
138 };
139
140 /*
141 * usb 2.0 devices need to expose both high speed and full speed
142 * descriptors, unless they only run at full speed.
143 */
144
145 static struct usb_endpoint_descriptor hs_ep_in_desc = {
146 .bLength = USB_DT_ENDPOINT_SIZE,
147 .bDescriptorType = USB_DT_ENDPOINT,
148 .bmAttributes = USB_ENDPOINT_XFER_BULK,
149 .wMaxPacketSize = cpu_to_le16(512)
150 };
151
152 static struct usb_endpoint_descriptor hs_ep_out_desc = {
153 .bLength = USB_DT_ENDPOINT_SIZE,
154 .bDescriptorType = USB_DT_ENDPOINT,
155 .bmAttributes = USB_ENDPOINT_XFER_BULK,
156 .wMaxPacketSize = cpu_to_le16(512)
157 };
158
159 static struct usb_descriptor_header *hs_printer_function[] = {
160 (struct usb_descriptor_header *) &intf_desc,
161 (struct usb_descriptor_header *) &hs_ep_in_desc,
162 (struct usb_descriptor_header *) &hs_ep_out_desc,
163 NULL
164 };
165
166 /*
167 * Added endpoint descriptors for 3.0 devices
168 */
169
170 static struct usb_endpoint_descriptor ss_ep_in_desc = {
171 .bLength = USB_DT_ENDPOINT_SIZE,
172 .bDescriptorType = USB_DT_ENDPOINT,
173 .bmAttributes = USB_ENDPOINT_XFER_BULK,
174 .wMaxPacketSize = cpu_to_le16(1024),
175 };
176
177 static struct usb_ss_ep_comp_descriptor ss_ep_in_comp_desc = {
178 .bLength = sizeof(ss_ep_in_comp_desc),
179 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
180 };
181
182 static struct usb_endpoint_descriptor ss_ep_out_desc = {
183 .bLength = USB_DT_ENDPOINT_SIZE,
184 .bDescriptorType = USB_DT_ENDPOINT,
185 .bmAttributes = USB_ENDPOINT_XFER_BULK,
186 .wMaxPacketSize = cpu_to_le16(1024),
187 };
188
189 static struct usb_ss_ep_comp_descriptor ss_ep_out_comp_desc = {
190 .bLength = sizeof(ss_ep_out_comp_desc),
191 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
192 };
193
194 static struct usb_descriptor_header *ss_printer_function[] = {
195 (struct usb_descriptor_header *) &intf_desc,
196 (struct usb_descriptor_header *) &ss_ep_in_desc,
197 (struct usb_descriptor_header *) &ss_ep_in_comp_desc,
198 (struct usb_descriptor_header *) &ss_ep_out_desc,
199 (struct usb_descriptor_header *) &ss_ep_out_comp_desc,
200 NULL
201 };
202
203 /* maxpacket and other transfer characteristics vary by speed. */
204 static inline struct usb_endpoint_descriptor *ep_desc(struct usb_gadget *gadget,
205 struct usb_endpoint_descriptor *fs,
206 struct usb_endpoint_descriptor *hs,
207 struct usb_endpoint_descriptor *ss)
208 {
209 switch (gadget->speed) {
210 case USB_SPEED_SUPER:
211 return ss;
212 case USB_SPEED_HIGH:
213 return hs;
214 default:
215 return fs;
216 }
217 }
218
219 /*-------------------------------------------------------------------------*/
220
221 static struct usb_request *
222 printer_req_alloc(struct usb_ep *ep, unsigned len, gfp_t gfp_flags)
223 {
224 struct usb_request *req;
225
226 req = usb_ep_alloc_request(ep, gfp_flags);
227
228 if (req != NULL) {
229 req->length = len;
230 req->buf = kmalloc(len, gfp_flags);
231 if (req->buf == NULL) {
232 usb_ep_free_request(ep, req);
233 return NULL;
234 }
235 }
236
237 return req;
238 }
239
240 static void
241 printer_req_free(struct usb_ep *ep, struct usb_request *req)
242 {
243 if (ep != NULL && req != NULL) {
244 kfree(req->buf);
245 usb_ep_free_request(ep, req);
246 }
247 }
248
249 /*-------------------------------------------------------------------------*/
250
251 static void rx_complete(struct usb_ep *ep, struct usb_request *req)
252 {
253 struct printer_dev *dev = ep->driver_data;
254 int status = req->status;
255 unsigned long flags;
256
257 spin_lock_irqsave(&dev->lock, flags);
258
259 list_del_init(&req->list); /* Remode from Active List */
260
261 switch (status) {
262
263 /* normal completion */
264 case 0:
265 if (req->actual > 0) {
266 list_add_tail(&req->list, &dev->rx_buffers);
267 DBG(dev, "G_Printer : rx length %d\n", req->actual);
268 } else {
269 list_add(&req->list, &dev->rx_reqs);
270 }
271 break;
272
273 /* software-driven interface shutdown */
274 case -ECONNRESET: /* unlink */
275 case -ESHUTDOWN: /* disconnect etc */
276 VDBG(dev, "rx shutdown, code %d\n", status);
277 list_add(&req->list, &dev->rx_reqs);
278 break;
279
280 /* for hardware automagic (such as pxa) */
281 case -ECONNABORTED: /* endpoint reset */
282 DBG(dev, "rx %s reset\n", ep->name);
283 list_add(&req->list, &dev->rx_reqs);
284 break;
285
286 /* data overrun */
287 case -EOVERFLOW:
288 /* FALLTHROUGH */
289
290 default:
291 DBG(dev, "rx status %d\n", status);
292 list_add(&req->list, &dev->rx_reqs);
293 break;
294 }
295
296 wake_up_interruptible(&dev->rx_wait);
297 spin_unlock_irqrestore(&dev->lock, flags);
298 }
299
300 static void tx_complete(struct usb_ep *ep, struct usb_request *req)
301 {
302 struct printer_dev *dev = ep->driver_data;
303
304 switch (req->status) {
305 default:
306 VDBG(dev, "tx err %d\n", req->status);
307 /* FALLTHROUGH */
308 case -ECONNRESET: /* unlink */
309 case -ESHUTDOWN: /* disconnect etc */
310 break;
311 case 0:
312 break;
313 }
314
315 spin_lock(&dev->lock);
316 /* Take the request struct off the active list and put it on the
317 * free list.
318 */
319 list_del_init(&req->list);
320 list_add(&req->list, &dev->tx_reqs);
321 wake_up_interruptible(&dev->tx_wait);
322 if (likely(list_empty(&dev->tx_reqs_active)))
323 wake_up_interruptible(&dev->tx_flush_wait);
324
325 spin_unlock(&dev->lock);
326 }
327
328 /*-------------------------------------------------------------------------*/
329
330 static int
331 printer_open(struct inode *inode, struct file *fd)
332 {
333 struct printer_dev *dev;
334 unsigned long flags;
335 int ret = -EBUSY;
336
337 dev = container_of(inode->i_cdev, struct printer_dev, printer_cdev);
338
339 spin_lock_irqsave(&dev->lock, flags);
340
341 if (!dev->printer_cdev_open) {
342 dev->printer_cdev_open = 1;
343 fd->private_data = dev;
344 ret = 0;
345 /* Change the printer status to show that it's on-line. */
346 dev->printer_status |= PRINTER_SELECTED;
347 }
348
349 spin_unlock_irqrestore(&dev->lock, flags);
350
351 DBG(dev, "printer_open returned %x\n", ret);
352 return ret;
353 }
354
355 static int
356 printer_close(struct inode *inode, struct file *fd)
357 {
358 struct printer_dev *dev = fd->private_data;
359 unsigned long flags;
360
361 spin_lock_irqsave(&dev->lock, flags);
362 dev->printer_cdev_open = 0;
363 fd->private_data = NULL;
364 /* Change printer status to show that the printer is off-line. */
365 dev->printer_status &= ~PRINTER_SELECTED;
366 spin_unlock_irqrestore(&dev->lock, flags);
367
368 DBG(dev, "printer_close\n");
369
370 return 0;
371 }
372
373 /* This function must be called with interrupts turned off. */
374 static void
375 setup_rx_reqs(struct printer_dev *dev)
376 {
377 struct usb_request *req;
378
379 while (likely(!list_empty(&dev->rx_reqs))) {
380 int error;
381
382 req = container_of(dev->rx_reqs.next,
383 struct usb_request, list);
384 list_del_init(&req->list);
385
386 /* The USB Host sends us whatever amount of data it wants to
387 * so we always set the length field to the full USB_BUFSIZE.
388 * If the amount of data is more than the read() caller asked
389 * for it will be stored in the request buffer until it is
390 * asked for by read().
391 */
392 req->length = USB_BUFSIZE;
393 req->complete = rx_complete;
394
395 /* here, we unlock, and only unlock, to avoid deadlock. */
396 spin_unlock(&dev->lock);
397 error = usb_ep_queue(dev->out_ep, req, GFP_ATOMIC);
398 spin_lock(&dev->lock);
399 if (error) {
400 DBG(dev, "rx submit --> %d\n", error);
401 list_add(&req->list, &dev->rx_reqs);
402 break;
403 }
404 /* if the req is empty, then add it into dev->rx_reqs_active. */
405 else if (list_empty(&req->list))
406 list_add(&req->list, &dev->rx_reqs_active);
407 }
408 }
409
410 static ssize_t
411 printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr)
412 {
413 struct printer_dev *dev = fd->private_data;
414 unsigned long flags;
415 size_t size;
416 size_t bytes_copied;
417 struct usb_request *req;
418 /* This is a pointer to the current USB rx request. */
419 struct usb_request *current_rx_req;
420 /* This is the number of bytes in the current rx buffer. */
421 size_t current_rx_bytes;
422 /* This is a pointer to the current rx buffer. */
423 u8 *current_rx_buf;
424
425 if (len == 0)
426 return -EINVAL;
427
428 DBG(dev, "printer_read trying to read %d bytes\n", (int)len);
429
430 mutex_lock(&dev->lock_printer_io);
431 spin_lock_irqsave(&dev->lock, flags);
432
433 /* We will use this flag later to check if a printer reset happened
434 * after we turn interrupts back on.
435 */
436 dev->reset_printer = 0;
437
438 setup_rx_reqs(dev);
439
440 bytes_copied = 0;
441 current_rx_req = dev->current_rx_req;
442 current_rx_bytes = dev->current_rx_bytes;
443 current_rx_buf = dev->current_rx_buf;
444 dev->current_rx_req = NULL;
445 dev->current_rx_bytes = 0;
446 dev->current_rx_buf = NULL;
447
448 /* Check if there is any data in the read buffers. Please note that
449 * current_rx_bytes is the number of bytes in the current rx buffer.
450 * If it is zero then check if there are any other rx_buffers that
451 * are on the completed list. We are only out of data if all rx
452 * buffers are empty.
453 */
454 if ((current_rx_bytes == 0) &&
455 (likely(list_empty(&dev->rx_buffers)))) {
456 /* Turn interrupts back on before sleeping. */
457 spin_unlock_irqrestore(&dev->lock, flags);
458
459 /*
460 * If no data is available check if this is a NON-Blocking
461 * call or not.
462 */
463 if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
464 mutex_unlock(&dev->lock_printer_io);
465 return -EAGAIN;
466 }
467
468 /* Sleep until data is available */
469 wait_event_interruptible(dev->rx_wait,
470 (likely(!list_empty(&dev->rx_buffers))));
471 spin_lock_irqsave(&dev->lock, flags);
472 }
473
474 /* We have data to return then copy it to the caller's buffer.*/
475 while ((current_rx_bytes || likely(!list_empty(&dev->rx_buffers)))
476 && len) {
477 if (current_rx_bytes == 0) {
478 req = container_of(dev->rx_buffers.next,
479 struct usb_request, list);
480 list_del_init(&req->list);
481
482 if (req->actual && req->buf) {
483 current_rx_req = req;
484 current_rx_bytes = req->actual;
485 current_rx_buf = req->buf;
486 } else {
487 list_add(&req->list, &dev->rx_reqs);
488 continue;
489 }
490 }
491
492 /* Don't leave irqs off while doing memory copies */
493 spin_unlock_irqrestore(&dev->lock, flags);
494
495 if (len > current_rx_bytes)
496 size = current_rx_bytes;
497 else
498 size = len;
499
500 size -= copy_to_user(buf, current_rx_buf, size);
501 bytes_copied += size;
502 len -= size;
503 buf += size;
504
505 spin_lock_irqsave(&dev->lock, flags);
506
507 /* We've disconnected or reset so return. */
508 if (dev->reset_printer) {
509 list_add(&current_rx_req->list, &dev->rx_reqs);
510 spin_unlock_irqrestore(&dev->lock, flags);
511 mutex_unlock(&dev->lock_printer_io);
512 return -EAGAIN;
513 }
514
515 /* If we not returning all the data left in this RX request
516 * buffer then adjust the amount of data left in the buffer.
517 * Othewise if we are done with this RX request buffer then
518 * requeue it to get any incoming data from the USB host.
519 */
520 if (size < current_rx_bytes) {
521 current_rx_bytes -= size;
522 current_rx_buf += size;
523 } else {
524 list_add(&current_rx_req->list, &dev->rx_reqs);
525 current_rx_bytes = 0;
526 current_rx_buf = NULL;
527 current_rx_req = NULL;
528 }
529 }
530
531 dev->current_rx_req = current_rx_req;
532 dev->current_rx_bytes = current_rx_bytes;
533 dev->current_rx_buf = current_rx_buf;
534
535 spin_unlock_irqrestore(&dev->lock, flags);
536 mutex_unlock(&dev->lock_printer_io);
537
538 DBG(dev, "printer_read returned %d bytes\n", (int)bytes_copied);
539
540 if (bytes_copied)
541 return bytes_copied;
542 else
543 return -EAGAIN;
544 }
545
546 static ssize_t
547 printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
548 {
549 struct printer_dev *dev = fd->private_data;
550 unsigned long flags;
551 size_t size; /* Amount of data in a TX request. */
552 size_t bytes_copied = 0;
553 struct usb_request *req;
554 int value;
555
556 DBG(dev, "printer_write trying to send %d bytes\n", (int)len);
557
558 if (len == 0)
559 return -EINVAL;
560
561 mutex_lock(&dev->lock_printer_io);
562 spin_lock_irqsave(&dev->lock, flags);
563
564 /* Check if a printer reset happens while we have interrupts on */
565 dev->reset_printer = 0;
566
567 /* Check if there is any available write buffers */
568 if (likely(list_empty(&dev->tx_reqs))) {
569 /* Turn interrupts back on before sleeping. */
570 spin_unlock_irqrestore(&dev->lock, flags);
571
572 /*
573 * If write buffers are available check if this is
574 * a NON-Blocking call or not.
575 */
576 if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
577 mutex_unlock(&dev->lock_printer_io);
578 return -EAGAIN;
579 }
580
581 /* Sleep until a write buffer is available */
582 wait_event_interruptible(dev->tx_wait,
583 (likely(!list_empty(&dev->tx_reqs))));
584 spin_lock_irqsave(&dev->lock, flags);
585 }
586
587 while (likely(!list_empty(&dev->tx_reqs)) && len) {
588
589 if (len > USB_BUFSIZE)
590 size = USB_BUFSIZE;
591 else
592 size = len;
593
594 req = container_of(dev->tx_reqs.next, struct usb_request,
595 list);
596 list_del_init(&req->list);
597
598 req->complete = tx_complete;
599 req->length = size;
600
601 /* Check if we need to send a zero length packet. */
602 if (len > size)
603 /* They will be more TX requests so no yet. */
604 req->zero = 0;
605 else
606 /* If the data amount is not a multiple of the
607 * maxpacket size then send a zero length packet.
608 */
609 req->zero = ((len % dev->in_ep->maxpacket) == 0);
610
611 /* Don't leave irqs off while doing memory copies */
612 spin_unlock_irqrestore(&dev->lock, flags);
613
614 if (copy_from_user(req->buf, buf, size)) {
615 list_add(&req->list, &dev->tx_reqs);
616 mutex_unlock(&dev->lock_printer_io);
617 return bytes_copied;
618 }
619
620 bytes_copied += size;
621 len -= size;
622 buf += size;
623
624 spin_lock_irqsave(&dev->lock, flags);
625
626 /* We've disconnected or reset so free the req and buffer */
627 if (dev->reset_printer) {
628 list_add(&req->list, &dev->tx_reqs);
629 spin_unlock_irqrestore(&dev->lock, flags);
630 mutex_unlock(&dev->lock_printer_io);
631 return -EAGAIN;
632 }
633
634 list_add(&req->list, &dev->tx_reqs_active);
635
636 /* here, we unlock, and only unlock, to avoid deadlock. */
637 spin_unlock(&dev->lock);
638 value = usb_ep_queue(dev->in_ep, req, GFP_ATOMIC);
639 spin_lock(&dev->lock);
640 if (value) {
641 list_del(&req->list);
642 list_add(&req->list, &dev->tx_reqs);
643 spin_unlock_irqrestore(&dev->lock, flags);
644 mutex_unlock(&dev->lock_printer_io);
645 return -EAGAIN;
646 }
647 }
648
649 spin_unlock_irqrestore(&dev->lock, flags);
650 mutex_unlock(&dev->lock_printer_io);
651
652 DBG(dev, "printer_write sent %d bytes\n", (int)bytes_copied);
653
654 if (bytes_copied)
655 return bytes_copied;
656 else
657 return -EAGAIN;
658 }
659
660 static int
661 printer_fsync(struct file *fd, loff_t start, loff_t end, int datasync)
662 {
663 struct printer_dev *dev = fd->private_data;
664 struct inode *inode = file_inode(fd);
665 unsigned long flags;
666 int tx_list_empty;
667
668 inode_lock(inode);
669 spin_lock_irqsave(&dev->lock, flags);
670 tx_list_empty = (likely(list_empty(&dev->tx_reqs)));
671 spin_unlock_irqrestore(&dev->lock, flags);
672
673 if (!tx_list_empty) {
674 /* Sleep until all data has been sent */
675 wait_event_interruptible(dev->tx_flush_wait,
676 (likely(list_empty(&dev->tx_reqs_active))));
677 }
678 inode_unlock(inode);
679
680 return 0;
681 }
682
683 static __poll_t
684 printer_poll(struct file *fd, poll_table *wait)
685 {
686 struct printer_dev *dev = fd->private_data;
687 unsigned long flags;
688 __poll_t status = 0;
689
690 mutex_lock(&dev->lock_printer_io);
691 spin_lock_irqsave(&dev->lock, flags);
692 setup_rx_reqs(dev);
693 spin_unlock_irqrestore(&dev->lock, flags);
694 mutex_unlock(&dev->lock_printer_io);
695
696 poll_wait(fd, &dev->rx_wait, wait);
697 poll_wait(fd, &dev->tx_wait, wait);
698
699 spin_lock_irqsave(&dev->lock, flags);
700 if (likely(!list_empty(&dev->tx_reqs)))
701 status |= EPOLLOUT | EPOLLWRNORM;
702
703 if (likely(dev->current_rx_bytes) ||
704 likely(!list_empty(&dev->rx_buffers)))
705 status |= EPOLLIN | EPOLLRDNORM;
706
707 spin_unlock_irqrestore(&dev->lock, flags);
708
709 return status;
710 }
711
712 static long
713 printer_ioctl(struct file *fd, unsigned int code, unsigned long arg)
714 {
715 struct printer_dev *dev = fd->private_data;
716 unsigned long flags;
717 int status = 0;
718
719 DBG(dev, "printer_ioctl: cmd=0x%4.4x, arg=%lu\n", code, arg);
720
721 /* handle ioctls */
722
723 spin_lock_irqsave(&dev->lock, flags);
724
725 switch (code) {
726 case GADGET_GET_PRINTER_STATUS:
727 status = (int)dev->printer_status;
728 break;
729 case GADGET_SET_PRINTER_STATUS:
730 dev->printer_status = (u8)arg;
731 break;
732 default:
733 /* could not handle ioctl */
734 DBG(dev, "printer_ioctl: ERROR cmd=0x%4.4xis not supported\n",
735 code);
736 status = -ENOTTY;
737 }
738
739 spin_unlock_irqrestore(&dev->lock, flags);
740
741 return status;
742 }
743
744 /* used after endpoint configuration */
745 static const struct file_operations printer_io_operations = {
746 .owner = THIS_MODULE,
747 .open = printer_open,
748 .read = printer_read,
749 .write = printer_write,
750 .fsync = printer_fsync,
751 .poll = printer_poll,
752 .unlocked_ioctl = printer_ioctl,
753 .release = printer_close,
754 .llseek = noop_llseek,
755 };
756
757 /*-------------------------------------------------------------------------*/
758
759 static int
760 set_printer_interface(struct printer_dev *dev)
761 {
762 int result = 0;
763
764 dev->in_ep->desc = ep_desc(dev->gadget, &fs_ep_in_desc, &hs_ep_in_desc,
765 &ss_ep_in_desc);
766 dev->in_ep->driver_data = dev;
767
768 dev->out_ep->desc = ep_desc(dev->gadget, &fs_ep_out_desc,
769 &hs_ep_out_desc, &ss_ep_out_desc);
770 dev->out_ep->driver_data = dev;
771
772 result = usb_ep_enable(dev->in_ep);
773 if (result != 0) {
774 DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result);
775 goto done;
776 }
777
778 result = usb_ep_enable(dev->out_ep);
779 if (result != 0) {
780 DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result);
781 goto done;
782 }
783
784 done:
785 /* on error, disable any endpoints */
786 if (result != 0) {
787 (void) usb_ep_disable(dev->in_ep);
788 (void) usb_ep_disable(dev->out_ep);
789 dev->in_ep->desc = NULL;
790 dev->out_ep->desc = NULL;
791 }
792
793 /* caller is responsible for cleanup on error */
794 return result;
795 }
796
797 static void printer_reset_interface(struct printer_dev *dev)
798 {
799 unsigned long flags;
800
801 if (dev->interface < 0)
802 return;
803
804 DBG(dev, "%s\n", __func__);
805
806 if (dev->in_ep->desc)
807 usb_ep_disable(dev->in_ep);
808
809 if (dev->out_ep->desc)
810 usb_ep_disable(dev->out_ep);
811
812 spin_lock_irqsave(&dev->lock, flags);
813 dev->in_ep->desc = NULL;
814 dev->out_ep->desc = NULL;
815 dev->interface = -1;
816 spin_unlock_irqrestore(&dev->lock, flags);
817 }
818
819 /* Change our operational Interface. */
820 static int set_interface(struct printer_dev *dev, unsigned number)
821 {
822 int result = 0;
823
824 /* Free the current interface */
825 printer_reset_interface(dev);
826
827 result = set_printer_interface(dev);
828 if (result)
829 printer_reset_interface(dev);
830 else
831 dev->interface = number;
832
833 if (!result)
834 INFO(dev, "Using interface %x\n", number);
835
836 return result;
837 }
838
839 static void printer_soft_reset(struct printer_dev *dev)
840 {
841 struct usb_request *req;
842
843 INFO(dev, "Received Printer Reset Request\n");
844
845 if (usb_ep_disable(dev->in_ep))
846 DBG(dev, "Failed to disable USB in_ep\n");
847 if (usb_ep_disable(dev->out_ep))
848 DBG(dev, "Failed to disable USB out_ep\n");
849
850 if (dev->current_rx_req != NULL) {
851 list_add(&dev->current_rx_req->list, &dev->rx_reqs);
852 dev->current_rx_req = NULL;
853 }
854 dev->current_rx_bytes = 0;
855 dev->current_rx_buf = NULL;
856 dev->reset_printer = 1;
857
858 while (likely(!(list_empty(&dev->rx_buffers)))) {
859 req = container_of(dev->rx_buffers.next, struct usb_request,
860 list);
861 list_del_init(&req->list);
862 list_add(&req->list, &dev->rx_reqs);
863 }
864
865 while (likely(!(list_empty(&dev->rx_reqs_active)))) {
866 req = container_of(dev->rx_buffers.next, struct usb_request,
867 list);
868 list_del_init(&req->list);
869 list_add(&req->list, &dev->rx_reqs);
870 }
871
872 while (likely(!(list_empty(&dev->tx_reqs_active)))) {
873 req = container_of(dev->tx_reqs_active.next,
874 struct usb_request, list);
875 list_del_init(&req->list);
876 list_add(&req->list, &dev->tx_reqs);
877 }
878
879 if (usb_ep_enable(dev->in_ep))
880 DBG(dev, "Failed to enable USB in_ep\n");
881 if (usb_ep_enable(dev->out_ep))
882 DBG(dev, "Failed to enable USB out_ep\n");
883
884 wake_up_interruptible(&dev->rx_wait);
885 wake_up_interruptible(&dev->tx_wait);
886 wake_up_interruptible(&dev->tx_flush_wait);
887 }
888
889 /*-------------------------------------------------------------------------*/
890
891 static bool gprinter_req_match(struct usb_function *f,
892 const struct usb_ctrlrequest *ctrl,
893 bool config0)
894 {
895 struct printer_dev *dev = func_to_printer(f);
896 u16 w_index = le16_to_cpu(ctrl->wIndex);
897 u16 w_value = le16_to_cpu(ctrl->wValue);
898 u16 w_length = le16_to_cpu(ctrl->wLength);
899
900 if (config0)
901 return false;
902
903 if ((ctrl->bRequestType & USB_RECIP_MASK) != USB_RECIP_INTERFACE ||
904 (ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS)
905 return false;
906
907 switch (ctrl->bRequest) {
908 case GET_DEVICE_ID:
909 w_index >>= 8;
910 if (USB_DIR_IN & ctrl->bRequestType)
911 break;
912 return false;
913 case GET_PORT_STATUS:
914 if (!w_value && w_length == 1 &&
915 (USB_DIR_IN & ctrl->bRequestType))
916 break;
917 return false;
918 case SOFT_RESET:
919 if (!w_value && !w_length &&
920 !(USB_DIR_IN & ctrl->bRequestType))
921 break;
922 /* fall through */
923 default:
924 return false;
925 }
926 return w_index == dev->interface;
927 }
928
929 /*
930 * The setup() callback implements all the ep0 functionality that's not
931 * handled lower down.
932 */
933 static int printer_func_setup(struct usb_function *f,
934 const struct usb_ctrlrequest *ctrl)
935 {
936 struct printer_dev *dev = func_to_printer(f);
937 struct usb_composite_dev *cdev = f->config->cdev;
938 struct usb_request *req = cdev->req;
939 u8 *buf = req->buf;
940 int value = -EOPNOTSUPP;
941 u16 wIndex = le16_to_cpu(ctrl->wIndex);
942 u16 wValue = le16_to_cpu(ctrl->wValue);
943 u16 wLength = le16_to_cpu(ctrl->wLength);
944
945 DBG(dev, "ctrl req%02x.%02x v%04x i%04x l%d\n",
946 ctrl->bRequestType, ctrl->bRequest, wValue, wIndex, wLength);
947
948 switch (ctrl->bRequestType&USB_TYPE_MASK) {
949 case USB_TYPE_CLASS:
950 switch (ctrl->bRequest) {
951 case GET_DEVICE_ID: /* Get the IEEE-1284 PNP String */
952 /* Only one printer interface is supported. */
953 if ((wIndex>>8) != dev->interface)
954 break;
955
956 if (!dev->pnp_string) {
957 value = 0;
958 break;
959 }
960 value = strlen(dev->pnp_string);
961 buf[0] = (value >> 8) & 0xFF;
962 buf[1] = value & 0xFF;
963 memcpy(buf + 2, dev->pnp_string, value);
964 DBG(dev, "1284 PNP String: %x %s\n", value,
965 dev->pnp_string);
966 break;
967
968 case GET_PORT_STATUS: /* Get Port Status */
969 /* Only one printer interface is supported. */
970 if (wIndex != dev->interface)
971 break;
972
973 buf[0] = dev->printer_status;
974 value = min_t(u16, wLength, 1);
975 break;
976
977 case SOFT_RESET: /* Soft Reset */
978 /* Only one printer interface is supported. */
979 if (wIndex != dev->interface)
980 break;
981
982 printer_soft_reset(dev);
983
984 value = 0;
985 break;
986
987 default:
988 goto unknown;
989 }
990 break;
991
992 default:
993 unknown:
994 VDBG(dev,
995 "unknown ctrl req%02x.%02x v%04x i%04x l%d\n",
996 ctrl->bRequestType, ctrl->bRequest,
997 wValue, wIndex, wLength);
998 break;
999 }
1000 /* host either stalls (value < 0) or reports success */
1001 if (value >= 0) {
1002 req->length = value;
1003 req->zero = value < wLength;
1004 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
1005 if (value < 0) {
1006 ERROR(dev, "%s:%d Error!\n", __func__, __LINE__);
1007 req->status = 0;
1008 }
1009 }
1010 return value;
1011 }
1012
1013 static int printer_func_bind(struct usb_configuration *c,
1014 struct usb_function *f)
1015 {
1016 struct usb_gadget *gadget = c->cdev->gadget;
1017 struct printer_dev *dev = func_to_printer(f);
1018 struct device *pdev;
1019 struct usb_composite_dev *cdev = c->cdev;
1020 struct usb_ep *in_ep;
1021 struct usb_ep *out_ep = NULL;
1022 struct usb_request *req;
1023 dev_t devt;
1024 int id;
1025 int ret;
1026 u32 i;
1027
1028 id = usb_interface_id(c, f);
1029 if (id < 0)
1030 return id;
1031 intf_desc.bInterfaceNumber = id;
1032
1033 /* finish hookup to lower layer ... */
1034 dev->gadget = gadget;
1035
1036 /* all we really need is bulk IN/OUT */
1037 in_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_in_desc);
1038 if (!in_ep) {
1039 autoconf_fail:
1040 dev_err(&cdev->gadget->dev, "can't autoconfigure on %s\n",
1041 cdev->gadget->name);
1042 return -ENODEV;
1043 }
1044
1045 out_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_out_desc);
1046 if (!out_ep)
1047 goto autoconf_fail;
1048
1049 /* assumes that all endpoints are dual-speed */
1050 hs_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
1051 hs_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
1052 ss_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
1053 ss_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
1054
1055 ret = usb_assign_descriptors(f, fs_printer_function,
1056 hs_printer_function, ss_printer_function, NULL);
1057 if (ret)
1058 return ret;
1059
1060 dev->in_ep = in_ep;
1061 dev->out_ep = out_ep;
1062
1063 ret = -ENOMEM;
1064 for (i = 0; i < dev->q_len; i++) {
1065 req = printer_req_alloc(dev->in_ep, USB_BUFSIZE, GFP_KERNEL);
1066 if (!req)
1067 goto fail_tx_reqs;
1068 list_add(&req->list, &dev->tx_reqs);
1069 }
1070
1071 for (i = 0; i < dev->q_len; i++) {
1072 req = printer_req_alloc(dev->out_ep, USB_BUFSIZE, GFP_KERNEL);
1073 if (!req)
1074 goto fail_rx_reqs;
1075 list_add(&req->list, &dev->rx_reqs);
1076 }
1077
1078 /* Setup the sysfs files for the printer gadget. */
1079 devt = MKDEV(major, dev->minor);
1080 pdev = device_create(usb_gadget_class, NULL, devt,
1081 NULL, "g_printer%d", dev->minor);
1082 if (IS_ERR(pdev)) {
1083 ERROR(dev, "Failed to create device: g_printer\n");
1084 ret = PTR_ERR(pdev);
1085 goto fail_rx_reqs;
1086 }
1087
1088 /*
1089 * Register a character device as an interface to a user mode
1090 * program that handles the printer specific functionality.
1091 */
1092 cdev_init(&dev->printer_cdev, &printer_io_operations);
1093 dev->printer_cdev.owner = THIS_MODULE;
1094 ret = cdev_add(&dev->printer_cdev, devt, 1);
1095 if (ret) {
1096 ERROR(dev, "Failed to open char device\n");
1097 goto fail_cdev_add;
1098 }
1099
1100 return 0;
1101
1102 fail_cdev_add:
1103 device_destroy(usb_gadget_class, devt);
1104
1105 fail_rx_reqs:
1106 while (!list_empty(&dev->rx_reqs)) {
1107 req = container_of(dev->rx_reqs.next, struct usb_request, list);
1108 list_del(&req->list);
1109 printer_req_free(dev->out_ep, req);
1110 }
1111
1112 fail_tx_reqs:
1113 while (!list_empty(&dev->tx_reqs)) {
1114 req = container_of(dev->tx_reqs.next, struct usb_request, list);
1115 list_del(&req->list);
1116 printer_req_free(dev->in_ep, req);
1117 }
1118
1119 return ret;
1120
1121 }
1122
1123 static int printer_func_set_alt(struct usb_function *f,
1124 unsigned intf, unsigned alt)
1125 {
1126 struct printer_dev *dev = func_to_printer(f);
1127 int ret = -ENOTSUPP;
1128
1129 if (!alt)
1130 ret = set_interface(dev, intf);
1131
1132 return ret;
1133 }
1134
1135 static void printer_func_disable(struct usb_function *f)
1136 {
1137 struct printer_dev *dev = func_to_printer(f);
1138
1139 DBG(dev, "%s\n", __func__);
1140
1141 printer_reset_interface(dev);
1142 }
1143
1144 static inline struct f_printer_opts
1145 *to_f_printer_opts(struct config_item *item)
1146 {
1147 return container_of(to_config_group(item), struct f_printer_opts,
1148 func_inst.group);
1149 }
1150
1151 static void printer_attr_release(struct config_item *item)
1152 {
1153 struct f_printer_opts *opts = to_f_printer_opts(item);
1154
1155 usb_put_function_instance(&opts->func_inst);
1156 }
1157
1158 static struct configfs_item_operations printer_item_ops = {
1159 .release = printer_attr_release,
1160 };
1161
1162 static ssize_t f_printer_opts_pnp_string_show(struct config_item *item,
1163 char *page)
1164 {
1165 struct f_printer_opts *opts = to_f_printer_opts(item);
1166 int result = 0;
1167
1168 mutex_lock(&opts->lock);
1169 if (!opts->pnp_string)
1170 goto unlock;
1171
1172 result = strlcpy(page, opts->pnp_string, PAGE_SIZE);
1173 if (result >= PAGE_SIZE) {
1174 result = PAGE_SIZE;
1175 } else if (page[result - 1] != '\n' && result + 1 < PAGE_SIZE) {
1176 page[result++] = '\n';
1177 page[result] = '\0';
1178 }
1179
1180 unlock:
1181 mutex_unlock(&opts->lock);
1182
1183 return result;
1184 }
1185
1186 static ssize_t f_printer_opts_pnp_string_store(struct config_item *item,
1187 const char *page, size_t len)
1188 {
1189 struct f_printer_opts *opts = to_f_printer_opts(item);
1190 char *new_pnp;
1191 int result;
1192
1193 mutex_lock(&opts->lock);
1194
1195 new_pnp = kstrndup(page, len, GFP_KERNEL);
1196 if (!new_pnp) {
1197 result = -ENOMEM;
1198 goto unlock;
1199 }
1200
1201 if (opts->pnp_string_allocated)
1202 kfree(opts->pnp_string);
1203
1204 opts->pnp_string_allocated = true;
1205 opts->pnp_string = new_pnp;
1206 result = len;
1207 unlock:
1208 mutex_unlock(&opts->lock);
1209
1210 return result;
1211 }
1212
1213 CONFIGFS_ATTR(f_printer_opts_, pnp_string);
1214
1215 static ssize_t f_printer_opts_q_len_show(struct config_item *item,
1216 char *page)
1217 {
1218 struct f_printer_opts *opts = to_f_printer_opts(item);
1219 int result;
1220
1221 mutex_lock(&opts->lock);
1222 result = sprintf(page, "%d\n", opts->q_len);
1223 mutex_unlock(&opts->lock);
1224
1225 return result;
1226 }
1227
1228 static ssize_t f_printer_opts_q_len_store(struct config_item *item,
1229 const char *page, size_t len)
1230 {
1231 struct f_printer_opts *opts = to_f_printer_opts(item);
1232 int ret;
1233 u16 num;
1234
1235 mutex_lock(&opts->lock);
1236 if (opts->refcnt) {
1237 ret = -EBUSY;
1238 goto end;
1239 }
1240
1241 ret = kstrtou16(page, 0, &num);
1242 if (ret)
1243 goto end;
1244
1245 opts->q_len = (unsigned)num;
1246 ret = len;
1247 end:
1248 mutex_unlock(&opts->lock);
1249 return ret;
1250 }
1251
1252 CONFIGFS_ATTR(f_printer_opts_, q_len);
1253
1254 static struct configfs_attribute *printer_attrs[] = {
1255 &f_printer_opts_attr_pnp_string,
1256 &f_printer_opts_attr_q_len,
1257 NULL,
1258 };
1259
1260 static const struct config_item_type printer_func_type = {
1261 .ct_item_ops = &printer_item_ops,
1262 .ct_attrs = printer_attrs,
1263 .ct_owner = THIS_MODULE,
1264 };
1265
1266 static inline int gprinter_get_minor(void)
1267 {
1268 int ret;
1269
1270 ret = ida_simple_get(&printer_ida, 0, 0, GFP_KERNEL);
1271 if (ret >= PRINTER_MINORS) {
1272 ida_simple_remove(&printer_ida, ret);
1273 ret = -ENODEV;
1274 }
1275
1276 return ret;
1277 }
1278
1279 static inline void gprinter_put_minor(int minor)
1280 {
1281 ida_simple_remove(&printer_ida, minor);
1282 }
1283
1284 static int gprinter_setup(int);
1285 static void gprinter_cleanup(void);
1286
1287 static void gprinter_free_inst(struct usb_function_instance *f)
1288 {
1289 struct f_printer_opts *opts;
1290
1291 opts = container_of(f, struct f_printer_opts, func_inst);
1292
1293 mutex_lock(&printer_ida_lock);
1294
1295 gprinter_put_minor(opts->minor);
1296 if (ida_is_empty(&printer_ida))
1297 gprinter_cleanup();
1298
1299 mutex_unlock(&printer_ida_lock);
1300
1301 if (opts->pnp_string_allocated)
1302 kfree(opts->pnp_string);
1303 kfree(opts);
1304 }
1305
1306 static struct usb_function_instance *gprinter_alloc_inst(void)
1307 {
1308 struct f_printer_opts *opts;
1309 struct usb_function_instance *ret;
1310 int status = 0;
1311
1312 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1313 if (!opts)
1314 return ERR_PTR(-ENOMEM);
1315
1316 mutex_init(&opts->lock);
1317 opts->func_inst.free_func_inst = gprinter_free_inst;
1318 ret = &opts->func_inst;
1319
1320 mutex_lock(&printer_ida_lock);
1321
1322 if (ida_is_empty(&printer_ida)) {
1323 status = gprinter_setup(PRINTER_MINORS);
1324 if (status) {
1325 ret = ERR_PTR(status);
1326 kfree(opts);
1327 goto unlock;
1328 }
1329 }
1330
1331 opts->minor = gprinter_get_minor();
1332 if (opts->minor < 0) {
1333 ret = ERR_PTR(opts->minor);
1334 kfree(opts);
1335 if (ida_is_empty(&printer_ida))
1336 gprinter_cleanup();
1337 goto unlock;
1338 }
1339 config_group_init_type_name(&opts->func_inst.group, "",
1340 &printer_func_type);
1341
1342 unlock:
1343 mutex_unlock(&printer_ida_lock);
1344 return ret;
1345 }
1346
1347 static void gprinter_free(struct usb_function *f)
1348 {
1349 struct printer_dev *dev = func_to_printer(f);
1350 struct f_printer_opts *opts;
1351
1352 opts = container_of(f->fi, struct f_printer_opts, func_inst);
1353 kfree(dev);
1354 mutex_lock(&opts->lock);
1355 --opts->refcnt;
1356 mutex_unlock(&opts->lock);
1357 }
1358
1359 static void printer_func_unbind(struct usb_configuration *c,
1360 struct usb_function *f)
1361 {
1362 struct printer_dev *dev;
1363 struct usb_request *req;
1364
1365 dev = func_to_printer(f);
1366
1367 device_destroy(usb_gadget_class, MKDEV(major, dev->minor));
1368
1369 /* Remove Character Device */
1370 cdev_del(&dev->printer_cdev);
1371
1372 /* we must already have been disconnected ... no i/o may be active */
1373 WARN_ON(!list_empty(&dev->tx_reqs_active));
1374 WARN_ON(!list_empty(&dev->rx_reqs_active));
1375
1376 /* Free all memory for this driver. */
1377 while (!list_empty(&dev->tx_reqs)) {
1378 req = container_of(dev->tx_reqs.next, struct usb_request,
1379 list);
1380 list_del(&req->list);
1381 printer_req_free(dev->in_ep, req);
1382 }
1383
1384 if (dev->current_rx_req != NULL)
1385 printer_req_free(dev->out_ep, dev->current_rx_req);
1386
1387 while (!list_empty(&dev->rx_reqs)) {
1388 req = container_of(dev->rx_reqs.next,
1389 struct usb_request, list);
1390 list_del(&req->list);
1391 printer_req_free(dev->out_ep, req);
1392 }
1393
1394 while (!list_empty(&dev->rx_buffers)) {
1395 req = container_of(dev->rx_buffers.next,
1396 struct usb_request, list);
1397 list_del(&req->list);
1398 printer_req_free(dev->out_ep, req);
1399 }
1400 usb_free_all_descriptors(f);
1401 }
1402
1403 static struct usb_function *gprinter_alloc(struct usb_function_instance *fi)
1404 {
1405 struct printer_dev *dev;
1406 struct f_printer_opts *opts;
1407
1408 opts = container_of(fi, struct f_printer_opts, func_inst);
1409
1410 mutex_lock(&opts->lock);
1411 if (opts->minor >= minors) {
1412 mutex_unlock(&opts->lock);
1413 return ERR_PTR(-ENOENT);
1414 }
1415
1416 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1417 if (!dev) {
1418 mutex_unlock(&opts->lock);
1419 return ERR_PTR(-ENOMEM);
1420 }
1421
1422 ++opts->refcnt;
1423 dev->minor = opts->minor;
1424 dev->pnp_string = opts->pnp_string;
1425 dev->q_len = opts->q_len;
1426 mutex_unlock(&opts->lock);
1427
1428 dev->function.name = "printer";
1429 dev->function.bind = printer_func_bind;
1430 dev->function.setup = printer_func_setup;
1431 dev->function.unbind = printer_func_unbind;
1432 dev->function.set_alt = printer_func_set_alt;
1433 dev->function.disable = printer_func_disable;
1434 dev->function.req_match = gprinter_req_match;
1435 dev->function.free_func = gprinter_free;
1436
1437 INIT_LIST_HEAD(&dev->tx_reqs);
1438 INIT_LIST_HEAD(&dev->rx_reqs);
1439 INIT_LIST_HEAD(&dev->rx_buffers);
1440 INIT_LIST_HEAD(&dev->tx_reqs_active);
1441 INIT_LIST_HEAD(&dev->rx_reqs_active);
1442
1443 spin_lock_init(&dev->lock);
1444 mutex_init(&dev->lock_printer_io);
1445 init_waitqueue_head(&dev->rx_wait);
1446 init_waitqueue_head(&dev->tx_wait);
1447 init_waitqueue_head(&dev->tx_flush_wait);
1448
1449 dev->interface = -1;
1450 dev->printer_cdev_open = 0;
1451 dev->printer_status = PRINTER_NOT_ERROR;
1452 dev->current_rx_req = NULL;
1453 dev->current_rx_bytes = 0;
1454 dev->current_rx_buf = NULL;
1455
1456 return &dev->function;
1457 }
1458
1459 DECLARE_USB_FUNCTION_INIT(printer, gprinter_alloc_inst, gprinter_alloc);
1460 MODULE_LICENSE("GPL");
1461 MODULE_AUTHOR("Craig Nadler");
1462
1463 static int gprinter_setup(int count)
1464 {
1465 int status;
1466 dev_t devt;
1467
1468 usb_gadget_class = class_create(THIS_MODULE, "usb_printer_gadget");
1469 if (IS_ERR(usb_gadget_class)) {
1470 status = PTR_ERR(usb_gadget_class);
1471 usb_gadget_class = NULL;
1472 pr_err("unable to create usb_gadget class %d\n", status);
1473 return status;
1474 }
1475
1476 status = alloc_chrdev_region(&devt, 0, count, "USB printer gadget");
1477 if (status) {
1478 pr_err("alloc_chrdev_region %d\n", status);
1479 class_destroy(usb_gadget_class);
1480 usb_gadget_class = NULL;
1481 return status;
1482 }
1483
1484 major = MAJOR(devt);
1485 minors = count;
1486
1487 return status;
1488 }
1489
1490 static void gprinter_cleanup(void)
1491 {
1492 if (major) {
1493 unregister_chrdev_region(MKDEV(major, 0), minors);
1494 major = minors = 0;
1495 }
1496 class_destroy(usb_gadget_class);
1497 usb_gadget_class = NULL;
1498 }
Linux with added FPC-III support