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);
367 DBG(dev, "printer_open returned %x\n", ret);
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);
385 DBG(dev, "printer_close\n");
390 /* This function must be called with interrupts turned off. */
392 setup_rx_reqs(struct printer_dev *dev)
394 struct usb_request *req;
396 while (likely(!list_empty(&dev->rx_reqs))) {
399 req = container_of(dev->rx_reqs.next,
400 struct usb_request, list);
401 list_del_init(&req->list);
403 /* The USB Host sends us whatever amount of data it wants to
404 * so we always set the length field to the full USB_BUFSIZE.
405 * If the amount of data is more than the read() caller asked
406 * for it will be stored in the request buffer until it is
407 * asked for by read().
409 req->length = USB_BUFSIZE;
410 req->complete = rx_complete;
412 /* here, we unlock, and only unlock, to avoid deadlock. */
413 spin_unlock(&dev->lock);
414 error = usb_ep_queue(dev->out_ep, req, GFP_ATOMIC);
415 spin_lock(&dev->lock);
417 DBG(dev, "rx submit --> %d\n", error);
418 list_add(&req->list, &dev->rx_reqs);
421 /* if the req is empty, then add it into dev->rx_reqs_active. */
422 else if (list_empty(&req->list))
423 list_add(&req->list, &dev->rx_reqs_active);
428 printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr)
430 struct printer_dev *dev = fd->private_data;
434 struct usb_request *req;
435 /* This is a pointer to the current USB rx request. */
436 struct usb_request *current_rx_req;
437 /* This is the number of bytes in the current rx buffer. */
438 size_t current_rx_bytes;
439 /* This is a pointer to the current rx buffer. */
445 DBG(dev, "printer_read trying to read %d bytes\n", (int)len);
447 mutex_lock(&dev->lock_printer_io);
448 spin_lock_irqsave(&dev->lock, flags);
450 if (dev->interface < 0) {
451 spin_unlock_irqrestore(&dev->lock, flags);
452 mutex_unlock(&dev->lock_printer_io);
456 /* We will use this flag later to check if a printer reset happened
457 * after we turn interrupts back on.
459 dev->reset_printer = 0;
464 current_rx_req = dev->current_rx_req;
465 current_rx_bytes = dev->current_rx_bytes;
466 current_rx_buf = dev->current_rx_buf;
467 dev->current_rx_req = NULL;
468 dev->current_rx_bytes = 0;
469 dev->current_rx_buf = NULL;
471 /* Check if there is any data in the read buffers. Please note that
472 * current_rx_bytes is the number of bytes in the current rx buffer.
473 * If it is zero then check if there are any other rx_buffers that
474 * are on the completed list. We are only out of data if all rx
477 if ((current_rx_bytes == 0) &&
478 (likely(list_empty(&dev->rx_buffers)))) {
479 /* Turn interrupts back on before sleeping. */
480 spin_unlock_irqrestore(&dev->lock, flags);
483 * If no data is available check if this is a NON-Blocking
486 if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
487 mutex_unlock(&dev->lock_printer_io);
491 /* Sleep until data is available */
492 wait_event_interruptible(dev->rx_wait,
493 (likely(!list_empty(&dev->rx_buffers))));
494 spin_lock_irqsave(&dev->lock, flags);
497 /* We have data to return then copy it to the caller's buffer.*/
498 while ((current_rx_bytes || likely(!list_empty(&dev->rx_buffers)))
500 if (current_rx_bytes == 0) {
501 req = container_of(dev->rx_buffers.next,
502 struct usb_request, list);
503 list_del_init(&req->list);
505 if (req->actual && req->buf) {
506 current_rx_req = req;
507 current_rx_bytes = req->actual;
508 current_rx_buf = req->buf;
510 list_add(&req->list, &dev->rx_reqs);
515 /* Don't leave irqs off while doing memory copies */
516 spin_unlock_irqrestore(&dev->lock, flags);
518 if (len > current_rx_bytes)
519 size = current_rx_bytes;
523 size -= copy_to_user(buf, current_rx_buf, size);
524 bytes_copied += size;
528 spin_lock_irqsave(&dev->lock, flags);
530 /* We've disconnected or reset so return. */
531 if (dev->reset_printer) {
532 list_add(¤t_rx_req->list, &dev->rx_reqs);
533 spin_unlock_irqrestore(&dev->lock, flags);
534 mutex_unlock(&dev->lock_printer_io);
538 /* If we not returning all the data left in this RX request
539 * buffer then adjust the amount of data left in the buffer.
540 * Othewise if we are done with this RX request buffer then
541 * requeue it to get any incoming data from the USB host.
543 if (size < current_rx_bytes) {
544 current_rx_bytes -= size;
545 current_rx_buf += size;
547 list_add(¤t_rx_req->list, &dev->rx_reqs);
548 current_rx_bytes = 0;
549 current_rx_buf = NULL;
550 current_rx_req = NULL;
554 dev->current_rx_req = current_rx_req;
555 dev->current_rx_bytes = current_rx_bytes;
556 dev->current_rx_buf = current_rx_buf;
558 spin_unlock_irqrestore(&dev->lock, flags);
559 mutex_unlock(&dev->lock_printer_io);
561 DBG(dev, "printer_read returned %d bytes\n", (int)bytes_copied);
570 printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
572 struct printer_dev *dev = fd->private_data;
574 size_t size; /* Amount of data in a TX request. */
575 size_t bytes_copied = 0;
576 struct usb_request *req;
579 DBG(dev, "printer_write trying to send %d bytes\n", (int)len);
584 mutex_lock(&dev->lock_printer_io);
585 spin_lock_irqsave(&dev->lock, flags);
587 if (dev->interface < 0) {
588 spin_unlock_irqrestore(&dev->lock, flags);
589 mutex_unlock(&dev->lock_printer_io);
593 /* Check if a printer reset happens while we have interrupts on */
594 dev->reset_printer = 0;
596 /* Check if there is any available write buffers */
597 if (likely(list_empty(&dev->tx_reqs))) {
598 /* Turn interrupts back on before sleeping. */
599 spin_unlock_irqrestore(&dev->lock, flags);
602 * If write buffers are available check if this is
603 * a NON-Blocking call or not.
605 if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
606 mutex_unlock(&dev->lock_printer_io);
610 /* Sleep until a write buffer is available */
611 wait_event_interruptible(dev->tx_wait,
612 (likely(!list_empty(&dev->tx_reqs))));
613 spin_lock_irqsave(&dev->lock, flags);
616 while (likely(!list_empty(&dev->tx_reqs)) && len) {
618 if (len > USB_BUFSIZE)
623 req = container_of(dev->tx_reqs.next, struct usb_request,
625 list_del_init(&req->list);
627 req->complete = tx_complete;
630 /* Check if we need to send a zero length packet. */
632 /* They will be more TX requests so no yet. */
635 /* If the data amount is not a multiple of the
636 * maxpacket size then send a zero length packet.
638 req->zero = ((len % dev->in_ep->maxpacket) == 0);
640 /* Don't leave irqs off while doing memory copies */
641 spin_unlock_irqrestore(&dev->lock, flags);
643 if (copy_from_user(req->buf, buf, size)) {
644 list_add(&req->list, &dev->tx_reqs);
645 mutex_unlock(&dev->lock_printer_io);
649 bytes_copied += size;
653 spin_lock_irqsave(&dev->lock, flags);
655 /* We've disconnected or reset so free the req and buffer */
656 if (dev->reset_printer) {
657 list_add(&req->list, &dev->tx_reqs);
658 spin_unlock_irqrestore(&dev->lock, flags);
659 mutex_unlock(&dev->lock_printer_io);
663 list_add(&req->list, &dev->tx_reqs_active);
665 /* here, we unlock, and only unlock, to avoid deadlock. */
666 spin_unlock(&dev->lock);
667 value = usb_ep_queue(dev->in_ep, req, GFP_ATOMIC);
668 spin_lock(&dev->lock);
670 list_del(&req->list);
671 list_add(&req->list, &dev->tx_reqs);
672 spin_unlock_irqrestore(&dev->lock, flags);
673 mutex_unlock(&dev->lock_printer_io);
678 spin_unlock_irqrestore(&dev->lock, flags);
679 mutex_unlock(&dev->lock_printer_io);
681 DBG(dev, "printer_write sent %d bytes\n", (int)bytes_copied);
690 printer_fsync(struct file *fd, loff_t start, loff_t end, int datasync)
692 struct printer_dev *dev = fd->private_data;
693 struct inode *inode = file_inode(fd);
698 spin_lock_irqsave(&dev->lock, flags);
700 if (dev->interface < 0) {
701 spin_unlock_irqrestore(&dev->lock, flags);
706 tx_list_empty = (likely(list_empty(&dev->tx_reqs)));
707 spin_unlock_irqrestore(&dev->lock, flags);
709 if (!tx_list_empty) {
710 /* Sleep until all data has been sent */
711 wait_event_interruptible(dev->tx_flush_wait,
712 (likely(list_empty(&dev->tx_reqs_active))));
720 printer_poll(struct file *fd, poll_table *wait)
722 struct printer_dev *dev = fd->private_data;
726 mutex_lock(&dev->lock_printer_io);
727 spin_lock_irqsave(&dev->lock, flags);
729 if (dev->interface < 0) {
730 spin_unlock_irqrestore(&dev->lock, flags);
731 mutex_unlock(&dev->lock_printer_io);
732 return EPOLLERR | EPOLLHUP;
736 spin_unlock_irqrestore(&dev->lock, flags);
737 mutex_unlock(&dev->lock_printer_io);
739 poll_wait(fd, &dev->rx_wait, wait);
740 poll_wait(fd, &dev->tx_wait, wait);
742 spin_lock_irqsave(&dev->lock, flags);
743 if (likely(!list_empty(&dev->tx_reqs)))
744 status |= EPOLLOUT | EPOLLWRNORM;
746 if (likely(dev->current_rx_bytes) ||
747 likely(!list_empty(&dev->rx_buffers)))
748 status |= EPOLLIN | EPOLLRDNORM;
750 spin_unlock_irqrestore(&dev->lock, flags);
756 printer_ioctl(struct file *fd, unsigned int code, unsigned long arg)
758 struct printer_dev *dev = fd->private_data;
762 DBG(dev, "printer_ioctl: cmd=0x%4.4x, arg=%lu\n", code, arg);
766 spin_lock_irqsave(&dev->lock, flags);
768 if (dev->interface < 0) {
769 spin_unlock_irqrestore(&dev->lock, flags);
774 case GADGET_GET_PRINTER_STATUS:
775 status = (int)dev->printer_status;
777 case GADGET_SET_PRINTER_STATUS:
778 dev->printer_status = (u8)arg;
781 /* could not handle ioctl */
782 DBG(dev, "printer_ioctl: ERROR cmd=0x%4.4xis not supported\n",
787 spin_unlock_irqrestore(&dev->lock, flags);
792 /* used after endpoint configuration */
793 static const struct file_operations printer_io_operations = {
794 .owner = THIS_MODULE,
795 .open = printer_open,
796 .read = printer_read,
797 .write = printer_write,
798 .fsync = printer_fsync,
799 .poll = printer_poll,
800 .unlocked_ioctl = printer_ioctl,
801 .release = printer_close,
802 .llseek = noop_llseek,
805 /*-------------------------------------------------------------------------*/
808 set_printer_interface(struct printer_dev *dev)
812 dev->in_ep->desc = ep_desc(dev->gadget, &fs_ep_in_desc, &hs_ep_in_desc,
814 dev->in_ep->driver_data = dev;
816 dev->out_ep->desc = ep_desc(dev->gadget, &fs_ep_out_desc,
817 &hs_ep_out_desc, &ss_ep_out_desc);
818 dev->out_ep->driver_data = dev;
820 result = usb_ep_enable(dev->in_ep);
822 DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result);
826 result = usb_ep_enable(dev->out_ep);
828 DBG(dev, "enable %s --> %d\n", dev->out_ep->name, result);
833 /* on error, disable any endpoints */
835 (void) usb_ep_disable(dev->in_ep);
836 (void) usb_ep_disable(dev->out_ep);
837 dev->in_ep->desc = NULL;
838 dev->out_ep->desc = NULL;
841 /* caller is responsible for cleanup on error */
845 static void printer_reset_interface(struct printer_dev *dev)
849 if (dev->interface < 0)
852 DBG(dev, "%s\n", __func__);
854 if (dev->in_ep->desc)
855 usb_ep_disable(dev->in_ep);
857 if (dev->out_ep->desc)
858 usb_ep_disable(dev->out_ep);
860 spin_lock_irqsave(&dev->lock, flags);
861 dev->in_ep->desc = NULL;
862 dev->out_ep->desc = NULL;
864 spin_unlock_irqrestore(&dev->lock, flags);
867 /* Change our operational Interface. */
868 static int set_interface(struct printer_dev *dev, unsigned number)
872 /* Free the current interface */
873 printer_reset_interface(dev);
875 result = set_printer_interface(dev);
877 printer_reset_interface(dev);
879 dev->interface = number;
882 INFO(dev, "Using interface %x\n", number);
887 static void printer_soft_reset(struct printer_dev *dev)
889 struct usb_request *req;
891 INFO(dev, "Received Printer Reset Request\n");
893 if (usb_ep_disable(dev->in_ep))
894 DBG(dev, "Failed to disable USB in_ep\n");
895 if (usb_ep_disable(dev->out_ep))
896 DBG(dev, "Failed to disable USB out_ep\n");
898 if (dev->current_rx_req != NULL) {
899 list_add(&dev->current_rx_req->list, &dev->rx_reqs);
900 dev->current_rx_req = NULL;
902 dev->current_rx_bytes = 0;
903 dev->current_rx_buf = NULL;
904 dev->reset_printer = 1;
906 while (likely(!(list_empty(&dev->rx_buffers)))) {
907 req = container_of(dev->rx_buffers.next, struct usb_request,
909 list_del_init(&req->list);
910 list_add(&req->list, &dev->rx_reqs);
913 while (likely(!(list_empty(&dev->rx_reqs_active)))) {
914 req = container_of(dev->rx_buffers.next, struct usb_request,
916 list_del_init(&req->list);
917 list_add(&req->list, &dev->rx_reqs);
920 while (likely(!(list_empty(&dev->tx_reqs_active)))) {
921 req = container_of(dev->tx_reqs_active.next,
922 struct usb_request, list);
923 list_del_init(&req->list);
924 list_add(&req->list, &dev->tx_reqs);
927 if (usb_ep_enable(dev->in_ep))
928 DBG(dev, "Failed to enable USB in_ep\n");
929 if (usb_ep_enable(dev->out_ep))
930 DBG(dev, "Failed to enable USB out_ep\n");
932 wake_up_interruptible(&dev->rx_wait);
933 wake_up_interruptible(&dev->tx_wait);
934 wake_up_interruptible(&dev->tx_flush_wait);
937 /*-------------------------------------------------------------------------*/
939 static bool gprinter_req_match(struct usb_function *f,
940 const struct usb_ctrlrequest *ctrl,
943 struct printer_dev *dev = func_to_printer(f);
944 u16 w_index = le16_to_cpu(ctrl->wIndex);
945 u16 w_value = le16_to_cpu(ctrl->wValue);
946 u16 w_length = le16_to_cpu(ctrl->wLength);
951 if ((ctrl->bRequestType & USB_RECIP_MASK) != USB_RECIP_INTERFACE ||
952 (ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS)
955 switch (ctrl->bRequest) {
958 if (USB_DIR_IN & ctrl->bRequestType)
961 case GET_PORT_STATUS:
962 if (!w_value && w_length == 1 &&
963 (USB_DIR_IN & ctrl->bRequestType))
967 if (!w_value && !w_length &&
968 !(USB_DIR_IN & ctrl->bRequestType))
974 return w_index == dev->interface;
978 * The setup() callback implements all the ep0 functionality that's not
979 * handled lower down.
981 static int printer_func_setup(struct usb_function *f,
982 const struct usb_ctrlrequest *ctrl)
984 struct printer_dev *dev = func_to_printer(f);
985 struct usb_composite_dev *cdev = f->config->cdev;
986 struct usb_request *req = cdev->req;
988 int value = -EOPNOTSUPP;
989 u16 wIndex = le16_to_cpu(ctrl->wIndex);
990 u16 wValue = le16_to_cpu(ctrl->wValue);
991 u16 wLength = le16_to_cpu(ctrl->wLength);
993 DBG(dev, "ctrl req%02x.%02x v%04x i%04x l%d\n",
994 ctrl->bRequestType, ctrl->bRequest, wValue, wIndex, wLength);
996 switch (ctrl->bRequestType&USB_TYPE_MASK) {
998 switch (ctrl->bRequest) {
999 case GET_DEVICE_ID: /* Get the IEEE-1284 PNP String */
1000 /* Only one printer interface is supported. */
1001 if ((wIndex>>8) != dev->interface)
1004 if (!dev->pnp_string) {
1008 value = strlen(dev->pnp_string);
1009 buf[0] = (value >> 8) & 0xFF;
1010 buf[1] = value & 0xFF;
1011 memcpy(buf + 2, dev->pnp_string, value);
1012 DBG(dev, "1284 PNP String: %x %s\n", value,
1016 case GET_PORT_STATUS: /* Get Port Status */
1017 /* Only one printer interface is supported. */
1018 if (wIndex != dev->interface)
1021 buf[0] = dev->printer_status;
1022 value = min_t(u16, wLength, 1);
1025 case SOFT_RESET: /* Soft Reset */
1026 /* Only one printer interface is supported. */
1027 if (wIndex != dev->interface)
1030 printer_soft_reset(dev);
1043 "unknown ctrl req%02x.%02x v%04x i%04x l%d\n",
1044 ctrl->bRequestType, ctrl->bRequest,
1045 wValue, wIndex, wLength);
1048 /* host either stalls (value < 0) or reports success */
1050 req->length = value;
1051 req->zero = value < wLength;
1052 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
1054 ERROR(dev, "%s:%d Error!\n", __func__, __LINE__);
1061 static int printer_func_bind(struct usb_configuration *c,
1062 struct usb_function *f)
1064 struct usb_gadget *gadget = c->cdev->gadget;
1065 struct printer_dev *dev = func_to_printer(f);
1066 struct device *pdev;
1067 struct usb_composite_dev *cdev = c->cdev;
1068 struct usb_ep *in_ep;
1069 struct usb_ep *out_ep = NULL;
1070 struct usb_request *req;
1076 id = usb_interface_id(c, f);
1079 intf_desc.bInterfaceNumber = id;
1081 /* finish hookup to lower layer ... */
1082 dev->gadget = gadget;
1084 /* all we really need is bulk IN/OUT */
1085 in_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_in_desc);
1088 dev_err(&cdev->gadget->dev, "can't autoconfigure on %s\n",
1089 cdev->gadget->name);
1093 out_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_out_desc);
1097 /* assumes that all endpoints are dual-speed */
1098 hs_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
1099 hs_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
1100 ss_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
1101 ss_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
1103 ret = usb_assign_descriptors(f, fs_printer_function,
1104 hs_printer_function, ss_printer_function, NULL);
1109 dev->out_ep = out_ep;
1112 for (i = 0; i < dev->q_len; i++) {
1113 req = printer_req_alloc(dev->in_ep, USB_BUFSIZE, GFP_KERNEL);
1116 list_add(&req->list, &dev->tx_reqs);
1119 for (i = 0; i < dev->q_len; i++) {
1120 req = printer_req_alloc(dev->out_ep, USB_BUFSIZE, GFP_KERNEL);
1123 list_add(&req->list, &dev->rx_reqs);
1126 /* Setup the sysfs files for the printer gadget. */
1127 devt = MKDEV(major, dev->minor);
1128 pdev = device_create(usb_gadget_class, NULL, devt,
1129 NULL, "g_printer%d", dev->minor);
1131 ERROR(dev, "Failed to create device: g_printer\n");
1132 ret = PTR_ERR(pdev);
1137 * Register a character device as an interface to a user mode
1138 * program that handles the printer specific functionality.
1140 cdev_init(&dev->printer_cdev, &printer_io_operations);
1141 dev->printer_cdev.owner = THIS_MODULE;
1142 ret = cdev_add(&dev->printer_cdev, devt, 1);
1144 ERROR(dev, "Failed to open char device\n");
1151 device_destroy(usb_gadget_class, devt);
1154 while (!list_empty(&dev->rx_reqs)) {
1155 req = container_of(dev->rx_reqs.next, struct usb_request, list);
1156 list_del(&req->list);
1157 printer_req_free(dev->out_ep, req);
1161 while (!list_empty(&dev->tx_reqs)) {
1162 req = container_of(dev->tx_reqs.next, struct usb_request, list);
1163 list_del(&req->list);
1164 printer_req_free(dev->in_ep, req);
1167 usb_free_all_descriptors(f);
1172 static int printer_func_set_alt(struct usb_function *f,
1173 unsigned intf, unsigned alt)
1175 struct printer_dev *dev = func_to_printer(f);
1176 int ret = -ENOTSUPP;
1179 ret = set_interface(dev, intf);
1184 static void printer_func_disable(struct usb_function *f)
1186 struct printer_dev *dev = func_to_printer(f);
1188 DBG(dev, "%s\n", __func__);
1190 printer_reset_interface(dev);
1193 static inline struct f_printer_opts
1194 *to_f_printer_opts(struct config_item *item)
1196 return container_of(to_config_group(item), struct f_printer_opts,
1200 static void printer_attr_release(struct config_item *item)
1202 struct f_printer_opts *opts = to_f_printer_opts(item);
1204 usb_put_function_instance(&opts->func_inst);
1207 static struct configfs_item_operations printer_item_ops = {
1208 .release = printer_attr_release,
1211 static ssize_t f_printer_opts_pnp_string_show(struct config_item *item,
1214 struct f_printer_opts *opts = to_f_printer_opts(item);
1217 mutex_lock(&opts->lock);
1218 if (!opts->pnp_string)
1221 result = strlcpy(page, opts->pnp_string, PAGE_SIZE);
1222 if (result >= PAGE_SIZE) {
1224 } else if (page[result - 1] != '\n' && result + 1 < PAGE_SIZE) {
1225 page[result++] = '\n';
1226 page[result] = '\0';
1230 mutex_unlock(&opts->lock);
1235 static ssize_t f_printer_opts_pnp_string_store(struct config_item *item,
1236 const char *page, size_t len)
1238 struct f_printer_opts *opts = to_f_printer_opts(item);
1242 mutex_lock(&opts->lock);
1244 new_pnp = kstrndup(page, len, GFP_KERNEL);
1250 if (opts->pnp_string_allocated)
1251 kfree(opts->pnp_string);
1253 opts->pnp_string_allocated = true;
1254 opts->pnp_string = new_pnp;
1257 mutex_unlock(&opts->lock);
1262 CONFIGFS_ATTR(f_printer_opts_, pnp_string);
1264 static ssize_t f_printer_opts_q_len_show(struct config_item *item,
1267 struct f_printer_opts *opts = to_f_printer_opts(item);
1270 mutex_lock(&opts->lock);
1271 result = sprintf(page, "%d\n", opts->q_len);
1272 mutex_unlock(&opts->lock);
1277 static ssize_t f_printer_opts_q_len_store(struct config_item *item,
1278 const char *page, size_t len)
1280 struct f_printer_opts *opts = to_f_printer_opts(item);
1284 mutex_lock(&opts->lock);
1290 ret = kstrtou16(page, 0, &num);
1294 opts->q_len = (unsigned)num;
1297 mutex_unlock(&opts->lock);
1301 CONFIGFS_ATTR(f_printer_opts_, q_len);
1303 static struct configfs_attribute *printer_attrs[] = {
1304 &f_printer_opts_attr_pnp_string,
1305 &f_printer_opts_attr_q_len,
1309 static const struct config_item_type printer_func_type = {
1310 .ct_item_ops = &printer_item_ops,
1311 .ct_attrs = printer_attrs,
1312 .ct_owner = THIS_MODULE,
1315 static inline int gprinter_get_minor(void)
1319 ret = ida_simple_get(&printer_ida, 0, 0, GFP_KERNEL);
1320 if (ret >= PRINTER_MINORS) {
1321 ida_simple_remove(&printer_ida, ret);
1328 static inline void gprinter_put_minor(int minor)
1330 ida_simple_remove(&printer_ida, minor);
1333 static int gprinter_setup(int);
1334 static void gprinter_cleanup(void);
1336 static void gprinter_free_inst(struct usb_function_instance *f)
1338 struct f_printer_opts *opts;
1340 opts = container_of(f, struct f_printer_opts, func_inst);
1342 mutex_lock(&printer_ida_lock);
1344 gprinter_put_minor(opts->minor);
1345 if (ida_is_empty(&printer_ida))
1348 mutex_unlock(&printer_ida_lock);
1350 if (opts->pnp_string_allocated)
1351 kfree(opts->pnp_string);
1355 static struct usb_function_instance *gprinter_alloc_inst(void)
1357 struct f_printer_opts *opts;
1358 struct usb_function_instance *ret;
1361 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1363 return ERR_PTR(-ENOMEM);
1365 mutex_init(&opts->lock);
1366 opts->func_inst.free_func_inst = gprinter_free_inst;
1367 ret = &opts->func_inst;
1369 /* Make sure q_len is initialized, otherwise the bound device can't support read/write! */
1370 opts->q_len = DEFAULT_Q_LEN;
1372 mutex_lock(&printer_ida_lock);
1374 if (ida_is_empty(&printer_ida)) {
1375 status = gprinter_setup(PRINTER_MINORS);
1377 ret = ERR_PTR(status);
1383 opts->minor = gprinter_get_minor();
1384 if (opts->minor < 0) {
1385 ret = ERR_PTR(opts->minor);
1387 if (ida_is_empty(&printer_ida))
1391 config_group_init_type_name(&opts->func_inst.group, "",
1392 &printer_func_type);
1395 mutex_unlock(&printer_ida_lock);
1399 static void gprinter_free(struct usb_function *f)
1401 struct printer_dev *dev = func_to_printer(f);
1402 struct f_printer_opts *opts;
1404 opts = container_of(f->fi, struct f_printer_opts, func_inst);
1406 kref_put(&dev->kref, printer_dev_free);
1407 mutex_lock(&opts->lock);
1409 mutex_unlock(&opts->lock);
1412 static void printer_func_unbind(struct usb_configuration *c,
1413 struct usb_function *f)
1415 struct printer_dev *dev;
1416 struct usb_request *req;
1418 dev = func_to_printer(f);
1420 device_destroy(usb_gadget_class, MKDEV(major, dev->minor));
1422 /* Remove Character Device */
1423 cdev_del(&dev->printer_cdev);
1425 /* we must already have been disconnected ... no i/o may be active */
1426 WARN_ON(!list_empty(&dev->tx_reqs_active));
1427 WARN_ON(!list_empty(&dev->rx_reqs_active));
1429 /* Free all memory for this driver. */
1430 while (!list_empty(&dev->tx_reqs)) {
1431 req = container_of(dev->tx_reqs.next, struct usb_request,
1433 list_del(&req->list);
1434 printer_req_free(dev->in_ep, req);
1437 if (dev->current_rx_req != NULL)
1438 printer_req_free(dev->out_ep, dev->current_rx_req);
1440 while (!list_empty(&dev->rx_reqs)) {
1441 req = container_of(dev->rx_reqs.next,
1442 struct usb_request, list);
1443 list_del(&req->list);
1444 printer_req_free(dev->out_ep, req);
1447 while (!list_empty(&dev->rx_buffers)) {
1448 req = container_of(dev->rx_buffers.next,
1449 struct usb_request, list);
1450 list_del(&req->list);
1451 printer_req_free(dev->out_ep, req);
1453 usb_free_all_descriptors(f);
1456 static struct usb_function *gprinter_alloc(struct usb_function_instance *fi)
1458 struct printer_dev *dev;
1459 struct f_printer_opts *opts;
1461 opts = container_of(fi, struct f_printer_opts, func_inst);
1463 mutex_lock(&opts->lock);
1464 if (opts->minor >= minors) {
1465 mutex_unlock(&opts->lock);
1466 return ERR_PTR(-ENOENT);
1469 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1471 mutex_unlock(&opts->lock);
1472 return ERR_PTR(-ENOMEM);
1475 kref_init(&dev->kref);
1477 dev->minor = opts->minor;
1478 dev->pnp_string = opts->pnp_string;
1479 dev->q_len = opts->q_len;
1480 mutex_unlock(&opts->lock);
1482 dev->function.name = "printer";
1483 dev->function.bind = printer_func_bind;
1484 dev->function.setup = printer_func_setup;
1485 dev->function.unbind = printer_func_unbind;
1486 dev->function.set_alt = printer_func_set_alt;
1487 dev->function.disable = printer_func_disable;
1488 dev->function.req_match = gprinter_req_match;
1489 dev->function.free_func = gprinter_free;
1491 INIT_LIST_HEAD(&dev->tx_reqs);
1492 INIT_LIST_HEAD(&dev->rx_reqs);
1493 INIT_LIST_HEAD(&dev->rx_buffers);
1494 INIT_LIST_HEAD(&dev->tx_reqs_active);
1495 INIT_LIST_HEAD(&dev->rx_reqs_active);
1497 spin_lock_init(&dev->lock);
1498 mutex_init(&dev->lock_printer_io);
1499 init_waitqueue_head(&dev->rx_wait);
1500 init_waitqueue_head(&dev->tx_wait);
1501 init_waitqueue_head(&dev->tx_flush_wait);
1503 dev->interface = -1;
1504 dev->printer_cdev_open = 0;
1505 dev->printer_status = PRINTER_NOT_ERROR;
1506 dev->current_rx_req = NULL;
1507 dev->current_rx_bytes = 0;
1508 dev->current_rx_buf = NULL;
1510 return &dev->function;
1513 DECLARE_USB_FUNCTION_INIT(printer, gprinter_alloc_inst, gprinter_alloc);
1514 MODULE_LICENSE("GPL");
1515 MODULE_AUTHOR("Craig Nadler");
1517 static int gprinter_setup(int count)
1522 usb_gadget_class = class_create(THIS_MODULE, "usb_printer_gadget");
1523 if (IS_ERR(usb_gadget_class)) {
1524 status = PTR_ERR(usb_gadget_class);
1525 usb_gadget_class = NULL;
1526 pr_err("unable to create usb_gadget class %d\n", status);
1530 status = alloc_chrdev_region(&devt, 0, count, "USB printer gadget");
1532 pr_err("alloc_chrdev_region %d\n", status);
1533 class_destroy(usb_gadget_class);
1534 usb_gadget_class = NULL;
1538 major = MAJOR(devt);
1544 static void gprinter_cleanup(void)
1547 unregister_chrdev_region(MKDEV(major, 0), minors);
1550 class_destroy(usb_gadget_class);
1551 usb_gadget_class = NULL;