1 // SPDX-License-Identifier: GPL-2.0+
3 * f_printer.c - USB printer function driver
5 * Copied from drivers/usb/gadget/legacy/printer.c,
8 * printer.c -- Printer gadget driver
10 * Copyright (C) 2003-2005 David Brownell
11 * Copyright (C) 2006 Craig W. Nadler
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>
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>
36 #include <asm/byteorder.h>
38 #include <linux/irq.h>
39 #include <linux/uaccess.h>
40 #include <asm/unaligned.h>
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>
47 #include "u_printer.h"
49 #define PRINTER_MINORS 4
50 #define GET_DEVICE_ID 0
51 #define GET_PORT_STATUS 1
54 #define DEFAULT_Q_LEN 10 /* same as legacy g_printer gadget */
56 static int major, minors;
57 static struct class *usb_gadget_class;
58 static DEFINE_IDA(printer_ida);
59 static DEFINE_MUTEX(printer_ida_lock); /* protects access do printer_ida */
61 /*-------------------------------------------------------------------------*/
64 spinlock_t lock; /* lock this structure */
65 /* lock buffer lists during read/write calls */
66 struct mutex lock_printer_io;
67 struct usb_gadget *gadget;
69 struct usb_ep *in_ep, *out_ep;
71 struct list_head rx_reqs; /* List of free RX structs */
72 struct list_head rx_reqs_active; /* List of Active RX xfers */
73 struct list_head rx_buffers; /* List of completed xfers */
74 /* wait until there is data to be read. */
75 wait_queue_head_t rx_wait;
76 struct list_head tx_reqs; /* List of free TX structs */
77 struct list_head tx_reqs_active; /* List of Active TX xfers */
78 /* Wait until there are write buffers available to use. */
79 wait_queue_head_t tx_wait;
80 /* Wait until all write buffers have been sent. */
81 wait_queue_head_t tx_flush_wait;
82 struct usb_request *current_rx_req;
83 size_t current_rx_bytes;
88 struct cdev printer_cdev;
90 wait_queue_head_t wait;
92 char **pnp_string; /* We don't own memory! */
93 struct usb_function function;
96 static inline struct printer_dev *func_to_printer(struct usb_function *f)
98 return container_of(f, struct printer_dev, function);
101 /*-------------------------------------------------------------------------*/
104 * DESCRIPTORS ... most are static, but strings and (full) configuration
105 * descriptors are built on demand.
108 /* holds our biggest descriptor */
109 #define USB_DESC_BUFSIZE 256
110 #define USB_BUFSIZE 8192
112 static struct usb_interface_descriptor intf_desc = {
113 .bLength = sizeof(intf_desc),
114 .bDescriptorType = USB_DT_INTERFACE,
116 .bInterfaceClass = USB_CLASS_PRINTER,
117 .bInterfaceSubClass = 1, /* Printer Sub-Class */
118 .bInterfaceProtocol = 2, /* Bi-Directional */
122 static struct usb_endpoint_descriptor fs_ep_in_desc = {
123 .bLength = USB_DT_ENDPOINT_SIZE,
124 .bDescriptorType = USB_DT_ENDPOINT,
125 .bEndpointAddress = USB_DIR_IN,
126 .bmAttributes = USB_ENDPOINT_XFER_BULK
129 static struct usb_endpoint_descriptor fs_ep_out_desc = {
130 .bLength = USB_DT_ENDPOINT_SIZE,
131 .bDescriptorType = USB_DT_ENDPOINT,
132 .bEndpointAddress = USB_DIR_OUT,
133 .bmAttributes = USB_ENDPOINT_XFER_BULK
136 static struct usb_descriptor_header *fs_printer_function[] = {
137 (struct usb_descriptor_header *) &intf_desc,
138 (struct usb_descriptor_header *) &fs_ep_in_desc,
139 (struct usb_descriptor_header *) &fs_ep_out_desc,
144 * usb 2.0 devices need to expose both high speed and full speed
145 * descriptors, unless they only run at full speed.
148 static struct usb_endpoint_descriptor hs_ep_in_desc = {
149 .bLength = USB_DT_ENDPOINT_SIZE,
150 .bDescriptorType = USB_DT_ENDPOINT,
151 .bmAttributes = USB_ENDPOINT_XFER_BULK,
152 .wMaxPacketSize = cpu_to_le16(512)
155 static struct usb_endpoint_descriptor hs_ep_out_desc = {
156 .bLength = USB_DT_ENDPOINT_SIZE,
157 .bDescriptorType = USB_DT_ENDPOINT,
158 .bmAttributes = USB_ENDPOINT_XFER_BULK,
159 .wMaxPacketSize = cpu_to_le16(512)
162 static struct usb_descriptor_header *hs_printer_function[] = {
163 (struct usb_descriptor_header *) &intf_desc,
164 (struct usb_descriptor_header *) &hs_ep_in_desc,
165 (struct usb_descriptor_header *) &hs_ep_out_desc,
170 * Added endpoint descriptors for 3.0 devices
173 static struct usb_endpoint_descriptor ss_ep_in_desc = {
174 .bLength = USB_DT_ENDPOINT_SIZE,
175 .bDescriptorType = USB_DT_ENDPOINT,
176 .bmAttributes = USB_ENDPOINT_XFER_BULK,
177 .wMaxPacketSize = cpu_to_le16(1024),
180 static struct usb_ss_ep_comp_descriptor ss_ep_in_comp_desc = {
181 .bLength = sizeof(ss_ep_in_comp_desc),
182 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
185 static struct usb_endpoint_descriptor ss_ep_out_desc = {
186 .bLength = USB_DT_ENDPOINT_SIZE,
187 .bDescriptorType = USB_DT_ENDPOINT,
188 .bmAttributes = USB_ENDPOINT_XFER_BULK,
189 .wMaxPacketSize = cpu_to_le16(1024),
192 static struct usb_ss_ep_comp_descriptor ss_ep_out_comp_desc = {
193 .bLength = sizeof(ss_ep_out_comp_desc),
194 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
197 static struct usb_descriptor_header *ss_printer_function[] = {
198 (struct usb_descriptor_header *) &intf_desc,
199 (struct usb_descriptor_header *) &ss_ep_in_desc,
200 (struct usb_descriptor_header *) &ss_ep_in_comp_desc,
201 (struct usb_descriptor_header *) &ss_ep_out_desc,
202 (struct usb_descriptor_header *) &ss_ep_out_comp_desc,
206 /* maxpacket and other transfer characteristics vary by speed. */
207 static inline struct usb_endpoint_descriptor *ep_desc(struct usb_gadget *gadget,
208 struct usb_endpoint_descriptor *fs,
209 struct usb_endpoint_descriptor *hs,
210 struct usb_endpoint_descriptor *ss)
212 switch (gadget->speed) {
213 case USB_SPEED_SUPER:
222 /*-------------------------------------------------------------------------*/
224 static void printer_dev_free(struct kref *kref)
226 struct printer_dev *dev = container_of(kref, struct printer_dev, kref);
231 static struct usb_request *
232 printer_req_alloc(struct usb_ep *ep, unsigned len, gfp_t gfp_flags)
234 struct usb_request *req;
236 req = usb_ep_alloc_request(ep, gfp_flags);
240 req->buf = kmalloc(len, gfp_flags);
241 if (req->buf == NULL) {
242 usb_ep_free_request(ep, req);
251 printer_req_free(struct usb_ep *ep, struct usb_request *req)
253 if (ep != NULL && req != NULL) {
255 usb_ep_free_request(ep, req);
259 /*-------------------------------------------------------------------------*/
261 static void rx_complete(struct usb_ep *ep, struct usb_request *req)
263 struct printer_dev *dev = ep->driver_data;
264 int status = req->status;
267 spin_lock_irqsave(&dev->lock, flags);
269 list_del_init(&req->list); /* Remode from Active List */
273 /* normal completion */
275 if (req->actual > 0) {
276 list_add_tail(&req->list, &dev->rx_buffers);
277 DBG(dev, "G_Printer : rx length %d\n", req->actual);
279 list_add(&req->list, &dev->rx_reqs);
283 /* software-driven interface shutdown */
284 case -ECONNRESET: /* unlink */
285 case -ESHUTDOWN: /* disconnect etc */
286 VDBG(dev, "rx shutdown, code %d\n", status);
287 list_add(&req->list, &dev->rx_reqs);
290 /* for hardware automagic (such as pxa) */
291 case -ECONNABORTED: /* endpoint reset */
292 DBG(dev, "rx %s reset\n", ep->name);
293 list_add(&req->list, &dev->rx_reqs);
301 DBG(dev, "rx status %d\n", status);
302 list_add(&req->list, &dev->rx_reqs);
306 wake_up_interruptible(&dev->rx_wait);
307 spin_unlock_irqrestore(&dev->lock, flags);
310 static void tx_complete(struct usb_ep *ep, struct usb_request *req)
312 struct printer_dev *dev = ep->driver_data;
314 switch (req->status) {
316 VDBG(dev, "tx err %d\n", req->status);
318 case -ECONNRESET: /* unlink */
319 case -ESHUTDOWN: /* disconnect etc */
325 spin_lock(&dev->lock);
326 /* Take the request struct off the active list and put it on the
329 list_del_init(&req->list);
330 list_add(&req->list, &dev->tx_reqs);
331 wake_up_interruptible(&dev->tx_wait);
332 if (likely(list_empty(&dev->tx_reqs_active)))
333 wake_up_interruptible(&dev->tx_flush_wait);
335 spin_unlock(&dev->lock);
338 /*-------------------------------------------------------------------------*/
341 printer_open(struct inode *inode, struct file *fd)
343 struct printer_dev *dev;
347 dev = container_of(inode->i_cdev, struct printer_dev, printer_cdev);
349 spin_lock_irqsave(&dev->lock, flags);
351 if (dev->interface < 0) {
352 spin_unlock_irqrestore(&dev->lock, flags);
356 if (!dev->printer_cdev_open) {
357 dev->printer_cdev_open = 1;
358 fd->private_data = dev;
360 /* Change the printer status to show that it's on-line. */
361 dev->printer_status |= PRINTER_SELECTED;
364 spin_unlock_irqrestore(&dev->lock, flags);
366 kref_get(&dev->kref);
372 printer_close(struct inode *inode, struct file *fd)
374 struct printer_dev *dev = fd->private_data;
377 spin_lock_irqsave(&dev->lock, flags);
378 dev->printer_cdev_open = 0;
379 fd->private_data = NULL;
380 /* Change printer status to show that the printer is off-line. */
381 dev->printer_status &= ~PRINTER_SELECTED;
382 spin_unlock_irqrestore(&dev->lock, flags);
384 kref_put(&dev->kref, printer_dev_free);
389 /* This function must be called with interrupts turned off. */
391 setup_rx_reqs(struct printer_dev *dev)
393 struct usb_request *req;
395 while (likely(!list_empty(&dev->rx_reqs))) {
398 req = container_of(dev->rx_reqs.next,
399 struct usb_request, list);
400 list_del_init(&req->list);
402 /* The USB Host sends us whatever amount of data it wants to
403 * so we always set the length field to the full USB_BUFSIZE.
404 * If the amount of data is more than the read() caller asked
405 * for it will be stored in the request buffer until it is
406 * asked for by read().
408 req->length = USB_BUFSIZE;
409 req->complete = rx_complete;
411 /* here, we unlock, and only unlock, to avoid deadlock. */
412 spin_unlock(&dev->lock);
413 error = usb_ep_queue(dev->out_ep, req, GFP_ATOMIC);
414 spin_lock(&dev->lock);
416 DBG(dev, "rx submit --> %d\n", error);
417 list_add(&req->list, &dev->rx_reqs);
420 /* if the req is empty, then add it into dev->rx_reqs_active. */
421 else if (list_empty(&req->list))
422 list_add(&req->list, &dev->rx_reqs_active);
427 printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr)
429 struct printer_dev *dev = fd->private_data;
433 struct usb_request *req;
434 /* This is a pointer to the current USB rx request. */
435 struct usb_request *current_rx_req;
436 /* This is the number of bytes in the current rx buffer. */
437 size_t current_rx_bytes;
438 /* This is a pointer to the current rx buffer. */
444 DBG(dev, "printer_read trying to read %d bytes\n", (int)len);
446 mutex_lock(&dev->lock_printer_io);
447 spin_lock_irqsave(&dev->lock, flags);
449 if (dev->interface < 0) {
450 spin_unlock_irqrestore(&dev->lock, flags);
451 mutex_unlock(&dev->lock_printer_io);
455 /* We will use this flag later to check if a printer reset happened
456 * after we turn interrupts back on.
458 dev->reset_printer = 0;
463 current_rx_req = dev->current_rx_req;
464 current_rx_bytes = dev->current_rx_bytes;
465 current_rx_buf = dev->current_rx_buf;
466 dev->current_rx_req = NULL;
467 dev->current_rx_bytes = 0;
468 dev->current_rx_buf = NULL;
470 /* Check if there is any data in the read buffers. Please note that
471 * current_rx_bytes is the number of bytes in the current rx buffer.
472 * If it is zero then check if there are any other rx_buffers that
473 * are on the completed list. We are only out of data if all rx
476 if ((current_rx_bytes == 0) &&
477 (likely(list_empty(&dev->rx_buffers)))) {
478 /* Turn interrupts back on before sleeping. */
479 spin_unlock_irqrestore(&dev->lock, flags);
482 * If no data is available check if this is a NON-Blocking
485 if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
486 mutex_unlock(&dev->lock_printer_io);
490 /* Sleep until data is available */
491 wait_event_interruptible(dev->rx_wait,
492 (likely(!list_empty(&dev->rx_buffers))));
493 spin_lock_irqsave(&dev->lock, flags);
496 /* We have data to return then copy it to the caller's buffer.*/
497 while ((current_rx_bytes || likely(!list_empty(&dev->rx_buffers)))
499 if (current_rx_bytes == 0) {
500 req = container_of(dev->rx_buffers.next,
501 struct usb_request, list);
502 list_del_init(&req->list);
504 if (req->actual && req->buf) {
505 current_rx_req = req;
506 current_rx_bytes = req->actual;
507 current_rx_buf = req->buf;
509 list_add(&req->list, &dev->rx_reqs);
514 /* Don't leave irqs off while doing memory copies */
515 spin_unlock_irqrestore(&dev->lock, flags);
517 if (len > current_rx_bytes)
518 size = current_rx_bytes;
522 size -= copy_to_user(buf, current_rx_buf, size);
523 bytes_copied += size;
527 spin_lock_irqsave(&dev->lock, flags);
529 /* We've disconnected or reset so return. */
530 if (dev->reset_printer) {
531 list_add(¤t_rx_req->list, &dev->rx_reqs);
532 spin_unlock_irqrestore(&dev->lock, flags);
533 mutex_unlock(&dev->lock_printer_io);
537 /* If we not returning all the data left in this RX request
538 * buffer then adjust the amount of data left in the buffer.
539 * Othewise if we are done with this RX request buffer then
540 * requeue it to get any incoming data from the USB host.
542 if (size < current_rx_bytes) {
543 current_rx_bytes -= size;
544 current_rx_buf += size;
546 list_add(¤t_rx_req->list, &dev->rx_reqs);
547 current_rx_bytes = 0;
548 current_rx_buf = NULL;
549 current_rx_req = NULL;
553 dev->current_rx_req = current_rx_req;
554 dev->current_rx_bytes = current_rx_bytes;
555 dev->current_rx_buf = current_rx_buf;
557 spin_unlock_irqrestore(&dev->lock, flags);
558 mutex_unlock(&dev->lock_printer_io);
560 DBG(dev, "printer_read returned %d bytes\n", (int)bytes_copied);
569 printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
571 struct printer_dev *dev = fd->private_data;
573 size_t size; /* Amount of data in a TX request. */
574 size_t bytes_copied = 0;
575 struct usb_request *req;
578 DBG(dev, "printer_write trying to send %d bytes\n", (int)len);
583 mutex_lock(&dev->lock_printer_io);
584 spin_lock_irqsave(&dev->lock, flags);
586 if (dev->interface < 0) {
587 spin_unlock_irqrestore(&dev->lock, flags);
588 mutex_unlock(&dev->lock_printer_io);
592 /* Check if a printer reset happens while we have interrupts on */
593 dev->reset_printer = 0;
595 /* Check if there is any available write buffers */
596 if (likely(list_empty(&dev->tx_reqs))) {
597 /* Turn interrupts back on before sleeping. */
598 spin_unlock_irqrestore(&dev->lock, flags);
601 * If write buffers are available check if this is
602 * a NON-Blocking call or not.
604 if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
605 mutex_unlock(&dev->lock_printer_io);
609 /* Sleep until a write buffer is available */
610 wait_event_interruptible(dev->tx_wait,
611 (likely(!list_empty(&dev->tx_reqs))));
612 spin_lock_irqsave(&dev->lock, flags);
615 while (likely(!list_empty(&dev->tx_reqs)) && len) {
617 if (len > USB_BUFSIZE)
622 req = container_of(dev->tx_reqs.next, struct usb_request,
624 list_del_init(&req->list);
626 req->complete = tx_complete;
629 /* Check if we need to send a zero length packet. */
631 /* They will be more TX requests so no yet. */
634 /* If the data amount is not a multiple of the
635 * maxpacket size then send a zero length packet.
637 req->zero = ((len % dev->in_ep->maxpacket) == 0);
639 /* Don't leave irqs off while doing memory copies */
640 spin_unlock_irqrestore(&dev->lock, flags);
642 if (copy_from_user(req->buf, buf, size)) {
643 list_add(&req->list, &dev->tx_reqs);
644 mutex_unlock(&dev->lock_printer_io);
648 bytes_copied += size;
652 spin_lock_irqsave(&dev->lock, flags);
654 /* We've disconnected or reset so free the req and buffer */
655 if (dev->reset_printer) {
656 list_add(&req->list, &dev->tx_reqs);
657 spin_unlock_irqrestore(&dev->lock, flags);
658 mutex_unlock(&dev->lock_printer_io);
662 list_add(&req->list, &dev->tx_reqs_active);
664 /* here, we unlock, and only unlock, to avoid deadlock. */
665 spin_unlock(&dev->lock);
666 value = usb_ep_queue(dev->in_ep, req, GFP_ATOMIC);
667 spin_lock(&dev->lock);
669 list_move(&req->list, &dev->tx_reqs);
670 spin_unlock_irqrestore(&dev->lock, flags);
671 mutex_unlock(&dev->lock_printer_io);
676 spin_unlock_irqrestore(&dev->lock, flags);
677 mutex_unlock(&dev->lock_printer_io);
679 DBG(dev, "printer_write sent %d bytes\n", (int)bytes_copied);
688 printer_fsync(struct file *fd, loff_t start, loff_t end, int datasync)
690 struct printer_dev *dev = fd->private_data;
691 struct inode *inode = file_inode(fd);
696 spin_lock_irqsave(&dev->lock, flags);
698 if (dev->interface < 0) {
699 spin_unlock_irqrestore(&dev->lock, flags);
704 tx_list_empty = (likely(list_empty(&dev->tx_reqs)));
705 spin_unlock_irqrestore(&dev->lock, flags);
707 if (!tx_list_empty) {
708 /* Sleep until all data has been sent */
709 wait_event_interruptible(dev->tx_flush_wait,
710 (likely(list_empty(&dev->tx_reqs_active))));
718 printer_poll(struct file *fd, poll_table *wait)
720 struct printer_dev *dev = fd->private_data;
724 mutex_lock(&dev->lock_printer_io);
725 spin_lock_irqsave(&dev->lock, flags);
727 if (dev->interface < 0) {
728 spin_unlock_irqrestore(&dev->lock, flags);
729 mutex_unlock(&dev->lock_printer_io);
730 return EPOLLERR | EPOLLHUP;
734 spin_unlock_irqrestore(&dev->lock, flags);
735 mutex_unlock(&dev->lock_printer_io);
737 poll_wait(fd, &dev->rx_wait, wait);
738 poll_wait(fd, &dev->tx_wait, wait);
740 spin_lock_irqsave(&dev->lock, flags);
741 if (likely(!list_empty(&dev->tx_reqs)))
742 status |= EPOLLOUT | EPOLLWRNORM;
744 if (likely(dev->current_rx_bytes) ||
745 likely(!list_empty(&dev->rx_buffers)))
746 status |= EPOLLIN | EPOLLRDNORM;
748 spin_unlock_irqrestore(&dev->lock, flags);
754 printer_ioctl(struct file *fd, unsigned int code, unsigned long arg)
756 struct printer_dev *dev = fd->private_data;
760 DBG(dev, "printer_ioctl: cmd=0x%4.4x, arg=%lu\n", code, arg);
764 spin_lock_irqsave(&dev->lock, flags);
766 if (dev->interface < 0) {
767 spin_unlock_irqrestore(&dev->lock, flags);
772 case GADGET_GET_PRINTER_STATUS:
773 status = (int)dev->printer_status;
775 case GADGET_SET_PRINTER_STATUS:
776 dev->printer_status = (u8)arg;
779 /* could not handle ioctl */
780 DBG(dev, "printer_ioctl: ERROR cmd=0x%4.4xis not supported\n",
785 spin_unlock_irqrestore(&dev->lock, flags);
790 /* used after endpoint configuration */
791 static const struct file_operations printer_io_operations = {
792 .owner = THIS_MODULE,
793 .open = printer_open,
794 .read = printer_read,
795 .write = printer_write,
796 .fsync = printer_fsync,
797 .poll = printer_poll,
798 .unlocked_ioctl = printer_ioctl,
799 .release = printer_close,
800 .llseek = noop_llseek,
803 /*-------------------------------------------------------------------------*/
806 set_printer_interface(struct printer_dev *dev)
810 dev->in_ep->desc = ep_desc(dev->gadget, &fs_ep_in_desc, &hs_ep_in_desc,
812 dev->in_ep->driver_data = dev;
814 dev->out_ep->desc = ep_desc(dev->gadget, &fs_ep_out_desc,
815 &hs_ep_out_desc, &ss_ep_out_desc);
816 dev->out_ep->driver_data = dev;
818 result = usb_ep_enable(dev->in_ep);
820 DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result);
824 result = usb_ep_enable(dev->out_ep);
826 DBG(dev, "enable %s --> %d\n", dev->out_ep->name, result);
831 /* on error, disable any endpoints */
833 (void) usb_ep_disable(dev->in_ep);
834 (void) usb_ep_disable(dev->out_ep);
835 dev->in_ep->desc = NULL;
836 dev->out_ep->desc = NULL;
839 /* caller is responsible for cleanup on error */
843 static void printer_reset_interface(struct printer_dev *dev)
847 if (dev->interface < 0)
850 if (dev->in_ep->desc)
851 usb_ep_disable(dev->in_ep);
853 if (dev->out_ep->desc)
854 usb_ep_disable(dev->out_ep);
856 spin_lock_irqsave(&dev->lock, flags);
857 dev->in_ep->desc = NULL;
858 dev->out_ep->desc = NULL;
860 spin_unlock_irqrestore(&dev->lock, flags);
863 /* Change our operational Interface. */
864 static int set_interface(struct printer_dev *dev, unsigned number)
868 /* Free the current interface */
869 printer_reset_interface(dev);
871 result = set_printer_interface(dev);
873 printer_reset_interface(dev);
875 dev->interface = number;
878 INFO(dev, "Using interface %x\n", number);
883 static void printer_soft_reset(struct printer_dev *dev)
885 struct usb_request *req;
887 if (usb_ep_disable(dev->in_ep))
888 DBG(dev, "Failed to disable USB in_ep\n");
889 if (usb_ep_disable(dev->out_ep))
890 DBG(dev, "Failed to disable USB out_ep\n");
892 if (dev->current_rx_req != NULL) {
893 list_add(&dev->current_rx_req->list, &dev->rx_reqs);
894 dev->current_rx_req = NULL;
896 dev->current_rx_bytes = 0;
897 dev->current_rx_buf = NULL;
898 dev->reset_printer = 1;
900 while (likely(!(list_empty(&dev->rx_buffers)))) {
901 req = container_of(dev->rx_buffers.next, struct usb_request,
903 list_del_init(&req->list);
904 list_add(&req->list, &dev->rx_reqs);
907 while (likely(!(list_empty(&dev->rx_reqs_active)))) {
908 req = container_of(dev->rx_buffers.next, struct usb_request,
910 list_del_init(&req->list);
911 list_add(&req->list, &dev->rx_reqs);
914 while (likely(!(list_empty(&dev->tx_reqs_active)))) {
915 req = container_of(dev->tx_reqs_active.next,
916 struct usb_request, list);
917 list_del_init(&req->list);
918 list_add(&req->list, &dev->tx_reqs);
921 if (usb_ep_enable(dev->in_ep))
922 DBG(dev, "Failed to enable USB in_ep\n");
923 if (usb_ep_enable(dev->out_ep))
924 DBG(dev, "Failed to enable USB out_ep\n");
926 wake_up_interruptible(&dev->rx_wait);
927 wake_up_interruptible(&dev->tx_wait);
928 wake_up_interruptible(&dev->tx_flush_wait);
931 /*-------------------------------------------------------------------------*/
933 static bool gprinter_req_match(struct usb_function *f,
934 const struct usb_ctrlrequest *ctrl,
937 struct printer_dev *dev = func_to_printer(f);
938 u16 w_index = le16_to_cpu(ctrl->wIndex);
939 u16 w_value = le16_to_cpu(ctrl->wValue);
940 u16 w_length = le16_to_cpu(ctrl->wLength);
945 if ((ctrl->bRequestType & USB_RECIP_MASK) != USB_RECIP_INTERFACE ||
946 (ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS)
949 switch (ctrl->bRequest) {
952 if (USB_DIR_IN & ctrl->bRequestType)
955 case GET_PORT_STATUS:
956 if (!w_value && w_length == 1 &&
957 (USB_DIR_IN & ctrl->bRequestType))
961 if (!w_value && !w_length &&
962 !(USB_DIR_IN & ctrl->bRequestType))
968 return w_index == dev->interface;
972 * The setup() callback implements all the ep0 functionality that's not
973 * handled lower down.
975 static int printer_func_setup(struct usb_function *f,
976 const struct usb_ctrlrequest *ctrl)
978 struct printer_dev *dev = func_to_printer(f);
979 struct usb_composite_dev *cdev = f->config->cdev;
980 struct usb_request *req = cdev->req;
982 int value = -EOPNOTSUPP;
983 u16 wIndex = le16_to_cpu(ctrl->wIndex);
984 u16 wValue = le16_to_cpu(ctrl->wValue);
985 u16 wLength = le16_to_cpu(ctrl->wLength);
987 DBG(dev, "ctrl req%02x.%02x v%04x i%04x l%d\n",
988 ctrl->bRequestType, ctrl->bRequest, wValue, wIndex, wLength);
990 switch (ctrl->bRequestType&USB_TYPE_MASK) {
992 switch (ctrl->bRequest) {
993 case GET_DEVICE_ID: /* Get the IEEE-1284 PNP String */
994 /* Only one printer interface is supported. */
995 if ((wIndex>>8) != dev->interface)
998 if (!*dev->pnp_string) {
1002 value = strlen(*dev->pnp_string);
1003 buf[0] = (value >> 8) & 0xFF;
1004 buf[1] = value & 0xFF;
1005 memcpy(buf + 2, *dev->pnp_string, value);
1006 DBG(dev, "1284 PNP String: %x %s\n", value,
1010 case GET_PORT_STATUS: /* Get Port Status */
1011 /* Only one printer interface is supported. */
1012 if (wIndex != dev->interface)
1015 buf[0] = dev->printer_status;
1016 value = min_t(u16, wLength, 1);
1019 case SOFT_RESET: /* Soft Reset */
1020 /* Only one printer interface is supported. */
1021 if (wIndex != dev->interface)
1024 printer_soft_reset(dev);
1037 "unknown ctrl req%02x.%02x v%04x i%04x l%d\n",
1038 ctrl->bRequestType, ctrl->bRequest,
1039 wValue, wIndex, wLength);
1042 /* host either stalls (value < 0) or reports success */
1044 req->length = value;
1045 req->zero = value < wLength;
1046 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
1048 ERROR(dev, "%s:%d Error!\n", __func__, __LINE__);
1055 static int printer_func_bind(struct usb_configuration *c,
1056 struct usb_function *f)
1058 struct usb_gadget *gadget = c->cdev->gadget;
1059 struct printer_dev *dev = func_to_printer(f);
1060 struct device *pdev;
1061 struct usb_composite_dev *cdev = c->cdev;
1062 struct usb_ep *in_ep;
1063 struct usb_ep *out_ep = NULL;
1064 struct usb_request *req;
1070 id = usb_interface_id(c, f);
1073 intf_desc.bInterfaceNumber = id;
1075 /* finish hookup to lower layer ... */
1076 dev->gadget = gadget;
1078 /* all we really need is bulk IN/OUT */
1079 in_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_in_desc);
1082 dev_err(&cdev->gadget->dev, "can't autoconfigure on %s\n",
1083 cdev->gadget->name);
1087 out_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_out_desc);
1091 /* assumes that all endpoints are dual-speed */
1092 hs_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
1093 hs_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
1094 ss_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
1095 ss_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
1097 ret = usb_assign_descriptors(f, fs_printer_function,
1098 hs_printer_function, ss_printer_function,
1099 ss_printer_function);
1104 dev->out_ep = out_ep;
1107 for (i = 0; i < dev->q_len; i++) {
1108 req = printer_req_alloc(dev->in_ep, USB_BUFSIZE, GFP_KERNEL);
1111 list_add(&req->list, &dev->tx_reqs);
1114 for (i = 0; i < dev->q_len; i++) {
1115 req = printer_req_alloc(dev->out_ep, USB_BUFSIZE, GFP_KERNEL);
1118 list_add(&req->list, &dev->rx_reqs);
1121 /* Setup the sysfs files for the printer gadget. */
1122 devt = MKDEV(major, dev->minor);
1123 pdev = device_create(usb_gadget_class, NULL, devt,
1124 NULL, "g_printer%d", dev->minor);
1126 ERROR(dev, "Failed to create device: g_printer\n");
1127 ret = PTR_ERR(pdev);
1132 * Register a character device as an interface to a user mode
1133 * program that handles the printer specific functionality.
1135 cdev_init(&dev->printer_cdev, &printer_io_operations);
1136 dev->printer_cdev.owner = THIS_MODULE;
1137 ret = cdev_add(&dev->printer_cdev, devt, 1);
1139 ERROR(dev, "Failed to open char device\n");
1146 device_destroy(usb_gadget_class, devt);
1149 while (!list_empty(&dev->rx_reqs)) {
1150 req = container_of(dev->rx_reqs.next, struct usb_request, list);
1151 list_del(&req->list);
1152 printer_req_free(dev->out_ep, req);
1156 while (!list_empty(&dev->tx_reqs)) {
1157 req = container_of(dev->tx_reqs.next, struct usb_request, list);
1158 list_del(&req->list);
1159 printer_req_free(dev->in_ep, req);
1162 usb_free_all_descriptors(f);
1167 static int printer_func_set_alt(struct usb_function *f,
1168 unsigned intf, unsigned alt)
1170 struct printer_dev *dev = func_to_printer(f);
1171 int ret = -ENOTSUPP;
1174 ret = set_interface(dev, intf);
1179 static void printer_func_disable(struct usb_function *f)
1181 struct printer_dev *dev = func_to_printer(f);
1183 printer_reset_interface(dev);
1186 static inline struct f_printer_opts
1187 *to_f_printer_opts(struct config_item *item)
1189 return container_of(to_config_group(item), struct f_printer_opts,
1193 static void printer_attr_release(struct config_item *item)
1195 struct f_printer_opts *opts = to_f_printer_opts(item);
1197 usb_put_function_instance(&opts->func_inst);
1200 static struct configfs_item_operations printer_item_ops = {
1201 .release = printer_attr_release,
1204 static ssize_t f_printer_opts_pnp_string_show(struct config_item *item,
1207 struct f_printer_opts *opts = to_f_printer_opts(item);
1210 mutex_lock(&opts->lock);
1211 if (!opts->pnp_string)
1214 result = strlcpy(page, opts->pnp_string, PAGE_SIZE);
1215 if (result >= PAGE_SIZE) {
1217 } else if (page[result - 1] != '\n' && result + 1 < PAGE_SIZE) {
1218 page[result++] = '\n';
1219 page[result] = '\0';
1223 mutex_unlock(&opts->lock);
1228 static ssize_t f_printer_opts_pnp_string_store(struct config_item *item,
1229 const char *page, size_t len)
1231 struct f_printer_opts *opts = to_f_printer_opts(item);
1235 mutex_lock(&opts->lock);
1237 new_pnp = kstrndup(page, len, GFP_KERNEL);
1243 if (opts->pnp_string_allocated)
1244 kfree(opts->pnp_string);
1246 opts->pnp_string_allocated = true;
1247 opts->pnp_string = new_pnp;
1250 mutex_unlock(&opts->lock);
1255 CONFIGFS_ATTR(f_printer_opts_, pnp_string);
1257 static ssize_t f_printer_opts_q_len_show(struct config_item *item,
1260 struct f_printer_opts *opts = to_f_printer_opts(item);
1263 mutex_lock(&opts->lock);
1264 result = sprintf(page, "%d\n", opts->q_len);
1265 mutex_unlock(&opts->lock);
1270 static ssize_t f_printer_opts_q_len_store(struct config_item *item,
1271 const char *page, size_t len)
1273 struct f_printer_opts *opts = to_f_printer_opts(item);
1277 mutex_lock(&opts->lock);
1283 ret = kstrtou16(page, 0, &num);
1287 opts->q_len = (unsigned)num;
1290 mutex_unlock(&opts->lock);
1294 CONFIGFS_ATTR(f_printer_opts_, q_len);
1296 static struct configfs_attribute *printer_attrs[] = {
1297 &f_printer_opts_attr_pnp_string,
1298 &f_printer_opts_attr_q_len,
1302 static const struct config_item_type printer_func_type = {
1303 .ct_item_ops = &printer_item_ops,
1304 .ct_attrs = printer_attrs,
1305 .ct_owner = THIS_MODULE,
1308 static inline int gprinter_get_minor(void)
1312 ret = ida_simple_get(&printer_ida, 0, 0, GFP_KERNEL);
1313 if (ret >= PRINTER_MINORS) {
1314 ida_simple_remove(&printer_ida, ret);
1321 static inline void gprinter_put_minor(int minor)
1323 ida_simple_remove(&printer_ida, minor);
1326 static int gprinter_setup(int);
1327 static void gprinter_cleanup(void);
1329 static void gprinter_free_inst(struct usb_function_instance *f)
1331 struct f_printer_opts *opts;
1333 opts = container_of(f, struct f_printer_opts, func_inst);
1335 mutex_lock(&printer_ida_lock);
1337 gprinter_put_minor(opts->minor);
1338 if (ida_is_empty(&printer_ida))
1341 mutex_unlock(&printer_ida_lock);
1343 if (opts->pnp_string_allocated)
1344 kfree(opts->pnp_string);
1348 static struct usb_function_instance *gprinter_alloc_inst(void)
1350 struct f_printer_opts *opts;
1351 struct usb_function_instance *ret;
1354 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1356 return ERR_PTR(-ENOMEM);
1358 mutex_init(&opts->lock);
1359 opts->func_inst.free_func_inst = gprinter_free_inst;
1360 ret = &opts->func_inst;
1362 /* Make sure q_len is initialized, otherwise the bound device can't support read/write! */
1363 opts->q_len = DEFAULT_Q_LEN;
1365 mutex_lock(&printer_ida_lock);
1367 if (ida_is_empty(&printer_ida)) {
1368 status = gprinter_setup(PRINTER_MINORS);
1370 ret = ERR_PTR(status);
1376 opts->minor = gprinter_get_minor();
1377 if (opts->minor < 0) {
1378 ret = ERR_PTR(opts->minor);
1380 if (ida_is_empty(&printer_ida))
1384 config_group_init_type_name(&opts->func_inst.group, "",
1385 &printer_func_type);
1388 mutex_unlock(&printer_ida_lock);
1392 static void gprinter_free(struct usb_function *f)
1394 struct printer_dev *dev = func_to_printer(f);
1395 struct f_printer_opts *opts;
1397 opts = container_of(f->fi, struct f_printer_opts, func_inst);
1399 kref_put(&dev->kref, printer_dev_free);
1400 mutex_lock(&opts->lock);
1402 mutex_unlock(&opts->lock);
1405 static void printer_func_unbind(struct usb_configuration *c,
1406 struct usb_function *f)
1408 struct printer_dev *dev;
1409 struct usb_request *req;
1411 dev = func_to_printer(f);
1413 device_destroy(usb_gadget_class, MKDEV(major, dev->minor));
1415 /* Remove Character Device */
1416 cdev_del(&dev->printer_cdev);
1418 /* we must already have been disconnected ... no i/o may be active */
1419 WARN_ON(!list_empty(&dev->tx_reqs_active));
1420 WARN_ON(!list_empty(&dev->rx_reqs_active));
1422 /* Free all memory for this driver. */
1423 while (!list_empty(&dev->tx_reqs)) {
1424 req = container_of(dev->tx_reqs.next, struct usb_request,
1426 list_del(&req->list);
1427 printer_req_free(dev->in_ep, req);
1430 if (dev->current_rx_req != NULL)
1431 printer_req_free(dev->out_ep, dev->current_rx_req);
1433 while (!list_empty(&dev->rx_reqs)) {
1434 req = container_of(dev->rx_reqs.next,
1435 struct usb_request, list);
1436 list_del(&req->list);
1437 printer_req_free(dev->out_ep, req);
1440 while (!list_empty(&dev->rx_buffers)) {
1441 req = container_of(dev->rx_buffers.next,
1442 struct usb_request, list);
1443 list_del(&req->list);
1444 printer_req_free(dev->out_ep, req);
1446 usb_free_all_descriptors(f);
1449 static struct usb_function *gprinter_alloc(struct usb_function_instance *fi)
1451 struct printer_dev *dev;
1452 struct f_printer_opts *opts;
1454 opts = container_of(fi, struct f_printer_opts, func_inst);
1456 mutex_lock(&opts->lock);
1457 if (opts->minor >= minors) {
1458 mutex_unlock(&opts->lock);
1459 return ERR_PTR(-ENOENT);
1462 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1464 mutex_unlock(&opts->lock);
1465 return ERR_PTR(-ENOMEM);
1468 kref_init(&dev->kref);
1470 dev->minor = opts->minor;
1471 dev->pnp_string = &opts->pnp_string;
1472 dev->q_len = opts->q_len;
1473 mutex_unlock(&opts->lock);
1475 dev->function.name = "printer";
1476 dev->function.bind = printer_func_bind;
1477 dev->function.setup = printer_func_setup;
1478 dev->function.unbind = printer_func_unbind;
1479 dev->function.set_alt = printer_func_set_alt;
1480 dev->function.disable = printer_func_disable;
1481 dev->function.req_match = gprinter_req_match;
1482 dev->function.free_func = gprinter_free;
1484 INIT_LIST_HEAD(&dev->tx_reqs);
1485 INIT_LIST_HEAD(&dev->rx_reqs);
1486 INIT_LIST_HEAD(&dev->rx_buffers);
1487 INIT_LIST_HEAD(&dev->tx_reqs_active);
1488 INIT_LIST_HEAD(&dev->rx_reqs_active);
1490 spin_lock_init(&dev->lock);
1491 mutex_init(&dev->lock_printer_io);
1492 init_waitqueue_head(&dev->rx_wait);
1493 init_waitqueue_head(&dev->tx_wait);
1494 init_waitqueue_head(&dev->tx_flush_wait);
1496 dev->interface = -1;
1497 dev->printer_cdev_open = 0;
1498 dev->printer_status = PRINTER_NOT_ERROR;
1499 dev->current_rx_req = NULL;
1500 dev->current_rx_bytes = 0;
1501 dev->current_rx_buf = NULL;
1503 return &dev->function;
1506 DECLARE_USB_FUNCTION_INIT(printer, gprinter_alloc_inst, gprinter_alloc);
1507 MODULE_LICENSE("GPL");
1508 MODULE_AUTHOR("Craig Nadler");
1510 static int gprinter_setup(int count)
1515 usb_gadget_class = class_create(THIS_MODULE, "usb_printer_gadget");
1516 if (IS_ERR(usb_gadget_class)) {
1517 status = PTR_ERR(usb_gadget_class);
1518 usb_gadget_class = NULL;
1519 pr_err("unable to create usb_gadget class %d\n", status);
1523 status = alloc_chrdev_region(&devt, 0, count, "USB printer gadget");
1525 pr_err("alloc_chrdev_region %d\n", status);
1526 class_destroy(usb_gadget_class);
1527 usb_gadget_class = NULL;
1531 major = MAJOR(devt);
1537 static void gprinter_cleanup(void)
1540 unregister_chrdev_region(MKDEV(major, 0), minors);
1543 class_destroy(usb_gadget_class);
1544 usb_gadget_class = NULL;