diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/usb/gadget/function/f_printer.c | 1552 |
1 files changed, 1552 insertions, 0 deletions
diff --git a/drivers/usb/gadget/function/f_printer.c b/drivers/usb/gadget/function/f_printer.c new file mode 100644 index 000000000..a881c69b1 --- /dev/null +++ b/drivers/usb/gadget/function/f_printer.c @@ -0,0 +1,1552 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * f_printer.c - USB printer function driver + * + * Copied from drivers/usb/gadget/legacy/printer.c, + * which was: + * + * printer.c -- Printer gadget driver + * + * Copyright (C) 2003-2005 David Brownell + * Copyright (C) 2006 Craig W. Nadler + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/delay.h> +#include <linux/ioport.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/mutex.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/idr.h> +#include <linux/timer.h> +#include <linux/list.h> +#include <linux/interrupt.h> +#include <linux/device.h> +#include <linux/moduleparam.h> +#include <linux/fs.h> +#include <linux/poll.h> +#include <linux/types.h> +#include <linux/ctype.h> +#include <linux/cdev.h> +#include <linux/kref.h> + +#include <asm/byteorder.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/uaccess.h> +#include <asm/unaligned.h> + +#include <linux/usb/ch9.h> +#include <linux/usb/composite.h> +#include <linux/usb/gadget.h> +#include <linux/usb/g_printer.h> + +#include "u_printer.h" + +#define PRINTER_MINORS 4 +#define GET_DEVICE_ID 0 +#define GET_PORT_STATUS 1 +#define SOFT_RESET 2 + +#define DEFAULT_Q_LEN 10 /* same as legacy g_printer gadget */ + +static int major, minors; +static struct class *usb_gadget_class; +static DEFINE_IDA(printer_ida); +static DEFINE_MUTEX(printer_ida_lock); /* protects access do printer_ida */ + +/*-------------------------------------------------------------------------*/ + +struct printer_dev { + spinlock_t lock; /* lock this structure */ + /* lock buffer lists during read/write calls */ + struct mutex lock_printer_io; + struct usb_gadget *gadget; + s8 interface; + struct usb_ep *in_ep, *out_ep; + struct kref kref; + struct list_head rx_reqs; /* List of free RX structs */ + struct list_head rx_reqs_active; /* List of Active RX xfers */ + struct list_head rx_buffers; /* List of completed xfers */ + /* wait until there is data to be read. */ + wait_queue_head_t rx_wait; + struct list_head tx_reqs; /* List of free TX structs */ + struct list_head tx_reqs_active; /* List of Active TX xfers */ + /* Wait until there are write buffers available to use. */ + wait_queue_head_t tx_wait; + /* Wait until all write buffers have been sent. */ + wait_queue_head_t tx_flush_wait; + struct usb_request *current_rx_req; + size_t current_rx_bytes; + u8 *current_rx_buf; + u8 printer_status; + u8 reset_printer; + int minor; + struct cdev printer_cdev; + u8 printer_cdev_open; + wait_queue_head_t wait; + unsigned q_len; + char **pnp_string; /* We don't own memory! */ + struct usb_function function; +}; + +static inline struct printer_dev *func_to_printer(struct usb_function *f) +{ + return container_of(f, struct printer_dev, function); +} + +/*-------------------------------------------------------------------------*/ + +/* + * DESCRIPTORS ... most are static, but strings and (full) configuration + * descriptors are built on demand. + */ + +/* holds our biggest descriptor */ +#define USB_DESC_BUFSIZE 256 +#define USB_BUFSIZE 8192 + +static struct usb_interface_descriptor intf_desc = { + .bLength = sizeof(intf_desc), + .bDescriptorType = USB_DT_INTERFACE, + .bNumEndpoints = 2, + .bInterfaceClass = USB_CLASS_PRINTER, + .bInterfaceSubClass = 1, /* Printer Sub-Class */ + .bInterfaceProtocol = 2, /* Bi-Directional */ + .iInterface = 0 +}; + +static struct usb_endpoint_descriptor fs_ep_in_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + .bEndpointAddress = USB_DIR_IN, + .bmAttributes = USB_ENDPOINT_XFER_BULK +}; + +static struct usb_endpoint_descriptor fs_ep_out_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + .bEndpointAddress = USB_DIR_OUT, + .bmAttributes = USB_ENDPOINT_XFER_BULK +}; + +static struct usb_descriptor_header *fs_printer_function[] = { + (struct usb_descriptor_header *) &intf_desc, + (struct usb_descriptor_header *) &fs_ep_in_desc, + (struct usb_descriptor_header *) &fs_ep_out_desc, + NULL +}; + +/* + * usb 2.0 devices need to expose both high speed and full speed + * descriptors, unless they only run at full speed. + */ + +static struct usb_endpoint_descriptor hs_ep_in_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = cpu_to_le16(512) +}; + +static struct usb_endpoint_descriptor hs_ep_out_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = cpu_to_le16(512) +}; + +static struct usb_descriptor_header *hs_printer_function[] = { + (struct usb_descriptor_header *) &intf_desc, + (struct usb_descriptor_header *) &hs_ep_in_desc, + (struct usb_descriptor_header *) &hs_ep_out_desc, + NULL +}; + +/* + * Added endpoint descriptors for 3.0 devices + */ + +static struct usb_endpoint_descriptor ss_ep_in_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = cpu_to_le16(1024), +}; + +static struct usb_ss_ep_comp_descriptor ss_ep_in_comp_desc = { + .bLength = sizeof(ss_ep_in_comp_desc), + .bDescriptorType = USB_DT_SS_ENDPOINT_COMP, +}; + +static struct usb_endpoint_descriptor ss_ep_out_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = cpu_to_le16(1024), +}; + +static struct usb_ss_ep_comp_descriptor ss_ep_out_comp_desc = { + .bLength = sizeof(ss_ep_out_comp_desc), + .bDescriptorType = USB_DT_SS_ENDPOINT_COMP, +}; + +static struct usb_descriptor_header *ss_printer_function[] = { + (struct usb_descriptor_header *) &intf_desc, + (struct usb_descriptor_header *) &ss_ep_in_desc, + (struct usb_descriptor_header *) &ss_ep_in_comp_desc, + (struct usb_descriptor_header *) &ss_ep_out_desc, + (struct usb_descriptor_header *) &ss_ep_out_comp_desc, + NULL +}; + +/* maxpacket and other transfer characteristics vary by speed. */ +static inline struct usb_endpoint_descriptor *ep_desc(struct usb_gadget *gadget, + struct usb_endpoint_descriptor *fs, + struct usb_endpoint_descriptor *hs, + struct usb_endpoint_descriptor *ss) +{ + switch (gadget->speed) { + case USB_SPEED_SUPER: + return ss; + case USB_SPEED_HIGH: + return hs; + default: + return fs; + } +} + +/*-------------------------------------------------------------------------*/ + +static void printer_dev_free(struct kref *kref) +{ + struct printer_dev *dev = container_of(kref, struct printer_dev, kref); + + kfree(dev); +} + +static struct usb_request * +printer_req_alloc(struct usb_ep *ep, unsigned len, gfp_t gfp_flags) +{ + struct usb_request *req; + + req = usb_ep_alloc_request(ep, gfp_flags); + + if (req != NULL) { + req->length = len; + req->buf = kmalloc(len, gfp_flags); + if (req->buf == NULL) { + usb_ep_free_request(ep, req); + return NULL; + } + } + + return req; +} + +static void +printer_req_free(struct usb_ep *ep, struct usb_request *req) +{ + if (ep != NULL && req != NULL) { + kfree(req->buf); + usb_ep_free_request(ep, req); + } +} + +/*-------------------------------------------------------------------------*/ + +static void rx_complete(struct usb_ep *ep, struct usb_request *req) +{ + struct printer_dev *dev = ep->driver_data; + int status = req->status; + unsigned long flags; + + spin_lock_irqsave(&dev->lock, flags); + + list_del_init(&req->list); /* Remode from Active List */ + + switch (status) { + + /* normal completion */ + case 0: + if (req->actual > 0) { + list_add_tail(&req->list, &dev->rx_buffers); + DBG(dev, "G_Printer : rx length %d\n", req->actual); + } else { + list_add(&req->list, &dev->rx_reqs); + } + break; + + /* software-driven interface shutdown */ + case -ECONNRESET: /* unlink */ + case -ESHUTDOWN: /* disconnect etc */ + VDBG(dev, "rx shutdown, code %d\n", status); + list_add(&req->list, &dev->rx_reqs); + break; + + /* for hardware automagic (such as pxa) */ + case -ECONNABORTED: /* endpoint reset */ + DBG(dev, "rx %s reset\n", ep->name); + list_add(&req->list, &dev->rx_reqs); + break; + + /* data overrun */ + case -EOVERFLOW: + fallthrough; + + default: + DBG(dev, "rx status %d\n", status); + list_add(&req->list, &dev->rx_reqs); + break; + } + + wake_up_interruptible(&dev->rx_wait); + spin_unlock_irqrestore(&dev->lock, flags); +} + +static void tx_complete(struct usb_ep *ep, struct usb_request *req) +{ + struct printer_dev *dev = ep->driver_data; + + switch (req->status) { + default: + VDBG(dev, "tx err %d\n", req->status); + fallthrough; + case -ECONNRESET: /* unlink */ + case -ESHUTDOWN: /* disconnect etc */ + break; + case 0: + break; + } + + spin_lock(&dev->lock); + /* Take the request struct off the active list and put it on the + * free list. + */ + list_del_init(&req->list); + list_add(&req->list, &dev->tx_reqs); + wake_up_interruptible(&dev->tx_wait); + if (likely(list_empty(&dev->tx_reqs_active))) + wake_up_interruptible(&dev->tx_flush_wait); + + spin_unlock(&dev->lock); +} + +/*-------------------------------------------------------------------------*/ + +static int +printer_open(struct inode *inode, struct file *fd) +{ + struct printer_dev *dev; + unsigned long flags; + int ret = -EBUSY; + + dev = container_of(inode->i_cdev, struct printer_dev, printer_cdev); + + spin_lock_irqsave(&dev->lock, flags); + + if (dev->interface < 0) { + spin_unlock_irqrestore(&dev->lock, flags); + return -ENODEV; + } + + if (!dev->printer_cdev_open) { + dev->printer_cdev_open = 1; + fd->private_data = dev; + ret = 0; + /* Change the printer status to show that it's on-line. */ + dev->printer_status |= PRINTER_SELECTED; + } + + spin_unlock_irqrestore(&dev->lock, flags); + + kref_get(&dev->kref); + DBG(dev, "printer_open returned %x\n", ret); + return ret; +} + +static int +printer_close(struct inode *inode, struct file *fd) +{ + struct printer_dev *dev = fd->private_data; + unsigned long flags; + + spin_lock_irqsave(&dev->lock, flags); + dev->printer_cdev_open = 0; + fd->private_data = NULL; + /* Change printer status to show that the printer is off-line. */ + dev->printer_status &= ~PRINTER_SELECTED; + spin_unlock_irqrestore(&dev->lock, flags); + + kref_put(&dev->kref, printer_dev_free); + DBG(dev, "printer_close\n"); + + return 0; +} + +/* This function must be called with interrupts turned off. */ +static void +setup_rx_reqs(struct printer_dev *dev) +{ + struct usb_request *req; + + while (likely(!list_empty(&dev->rx_reqs))) { + int error; + + req = container_of(dev->rx_reqs.next, + struct usb_request, list); + list_del_init(&req->list); + + /* The USB Host sends us whatever amount of data it wants to + * so we always set the length field to the full USB_BUFSIZE. + * If the amount of data is more than the read() caller asked + * for it will be stored in the request buffer until it is + * asked for by read(). + */ + req->length = USB_BUFSIZE; + req->complete = rx_complete; + + /* here, we unlock, and only unlock, to avoid deadlock. */ + spin_unlock(&dev->lock); + error = usb_ep_queue(dev->out_ep, req, GFP_ATOMIC); + spin_lock(&dev->lock); + if (error) { + DBG(dev, "rx submit --> %d\n", error); + list_add(&req->list, &dev->rx_reqs); + break; + } + /* if the req is empty, then add it into dev->rx_reqs_active. */ + else if (list_empty(&req->list)) + list_add(&req->list, &dev->rx_reqs_active); + } +} + +static ssize_t +printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr) +{ + struct printer_dev *dev = fd->private_data; + unsigned long flags; + size_t size; + size_t bytes_copied; + struct usb_request *req; + /* This is a pointer to the current USB rx request. */ + struct usb_request *current_rx_req; + /* This is the number of bytes in the current rx buffer. */ + size_t current_rx_bytes; + /* This is a pointer to the current rx buffer. */ + u8 *current_rx_buf; + + if (len == 0) + return -EINVAL; + + DBG(dev, "printer_read trying to read %d bytes\n", (int)len); + + mutex_lock(&dev->lock_printer_io); + spin_lock_irqsave(&dev->lock, flags); + + if (dev->interface < 0) { + spin_unlock_irqrestore(&dev->lock, flags); + mutex_unlock(&dev->lock_printer_io); + return -ENODEV; + } + + /* We will use this flag later to check if a printer reset happened + * after we turn interrupts back on. + */ + dev->reset_printer = 0; + + setup_rx_reqs(dev); + + bytes_copied = 0; + current_rx_req = dev->current_rx_req; + current_rx_bytes = dev->current_rx_bytes; + current_rx_buf = dev->current_rx_buf; + dev->current_rx_req = NULL; + dev->current_rx_bytes = 0; + dev->current_rx_buf = NULL; + + /* Check if there is any data in the read buffers. Please note that + * current_rx_bytes is the number of bytes in the current rx buffer. + * If it is zero then check if there are any other rx_buffers that + * are on the completed list. We are only out of data if all rx + * buffers are empty. + */ + if ((current_rx_bytes == 0) && + (likely(list_empty(&dev->rx_buffers)))) { + /* Turn interrupts back on before sleeping. */ + spin_unlock_irqrestore(&dev->lock, flags); + + /* + * If no data is available check if this is a NON-Blocking + * call or not. + */ + if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) { + mutex_unlock(&dev->lock_printer_io); + return -EAGAIN; + } + + /* Sleep until data is available */ + wait_event_interruptible(dev->rx_wait, + (likely(!list_empty(&dev->rx_buffers)))); + spin_lock_irqsave(&dev->lock, flags); + } + + /* We have data to return then copy it to the caller's buffer.*/ + while ((current_rx_bytes || likely(!list_empty(&dev->rx_buffers))) + && len) { + if (current_rx_bytes == 0) { + req = container_of(dev->rx_buffers.next, + struct usb_request, list); + list_del_init(&req->list); + + if (req->actual && req->buf) { + current_rx_req = req; + current_rx_bytes = req->actual; + current_rx_buf = req->buf; + } else { + list_add(&req->list, &dev->rx_reqs); + continue; + } + } + + /* Don't leave irqs off while doing memory copies */ + spin_unlock_irqrestore(&dev->lock, flags); + + if (len > current_rx_bytes) + size = current_rx_bytes; + else + size = len; + + size -= copy_to_user(buf, current_rx_buf, size); + bytes_copied += size; + len -= size; + buf += size; + + spin_lock_irqsave(&dev->lock, flags); + + /* We've disconnected or reset so return. */ + if (dev->reset_printer) { + list_add(¤t_rx_req->list, &dev->rx_reqs); + spin_unlock_irqrestore(&dev->lock, flags); + mutex_unlock(&dev->lock_printer_io); + return -EAGAIN; + } + + /* If we not returning all the data left in this RX request + * buffer then adjust the amount of data left in the buffer. + * Othewise if we are done with this RX request buffer then + * requeue it to get any incoming data from the USB host. + */ + if (size < current_rx_bytes) { + current_rx_bytes -= size; + current_rx_buf += size; + } else { + list_add(¤t_rx_req->list, &dev->rx_reqs); + current_rx_bytes = 0; + current_rx_buf = NULL; + current_rx_req = NULL; + } + } + + dev->current_rx_req = current_rx_req; + dev->current_rx_bytes = current_rx_bytes; + dev->current_rx_buf = current_rx_buf; + + spin_unlock_irqrestore(&dev->lock, flags); + mutex_unlock(&dev->lock_printer_io); + + DBG(dev, "printer_read returned %d bytes\n", (int)bytes_copied); + + if (bytes_copied) + return bytes_copied; + else + return -EAGAIN; +} + +static ssize_t +printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr) +{ + struct printer_dev *dev = fd->private_data; + unsigned long flags; + size_t size; /* Amount of data in a TX request. */ + size_t bytes_copied = 0; + struct usb_request *req; + int value; + + DBG(dev, "printer_write trying to send %d bytes\n", (int)len); + + if (len == 0) + return -EINVAL; + + mutex_lock(&dev->lock_printer_io); + spin_lock_irqsave(&dev->lock, flags); + + if (dev->interface < 0) { + spin_unlock_irqrestore(&dev->lock, flags); + mutex_unlock(&dev->lock_printer_io); + return -ENODEV; + } + + /* Check if a printer reset happens while we have interrupts on */ + dev->reset_printer = 0; + + /* Check if there is any available write buffers */ + if (likely(list_empty(&dev->tx_reqs))) { + /* Turn interrupts back on before sleeping. */ + spin_unlock_irqrestore(&dev->lock, flags); + + /* + * If write buffers are available check if this is + * a NON-Blocking call or not. + */ + if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) { + mutex_unlock(&dev->lock_printer_io); + return -EAGAIN; + } + + /* Sleep until a write buffer is available */ + wait_event_interruptible(dev->tx_wait, + (likely(!list_empty(&dev->tx_reqs)))); + spin_lock_irqsave(&dev->lock, flags); + } + + while (likely(!list_empty(&dev->tx_reqs)) && len) { + + if (len > USB_BUFSIZE) + size = USB_BUFSIZE; + else + size = len; + + req = container_of(dev->tx_reqs.next, struct usb_request, + list); + list_del_init(&req->list); + + req->complete = tx_complete; + req->length = size; + + /* Check if we need to send a zero length packet. */ + if (len > size) + /* They will be more TX requests so no yet. */ + req->zero = 0; + else + /* If the data amount is not a multiple of the + * maxpacket size then send a zero length packet. + */ + req->zero = ((len % dev->in_ep->maxpacket) == 0); + + /* Don't leave irqs off while doing memory copies */ + spin_unlock_irqrestore(&dev->lock, flags); + + if (copy_from_user(req->buf, buf, size)) { + list_add(&req->list, &dev->tx_reqs); + mutex_unlock(&dev->lock_printer_io); + return bytes_copied; + } + + bytes_copied += size; + len -= size; + buf += size; + + spin_lock_irqsave(&dev->lock, flags); + + /* We've disconnected or reset so free the req and buffer */ + if (dev->reset_printer) { + list_add(&req->list, &dev->tx_reqs); + spin_unlock_irqrestore(&dev->lock, flags); + mutex_unlock(&dev->lock_printer_io); + return -EAGAIN; + } + + list_add(&req->list, &dev->tx_reqs_active); + + /* here, we unlock, and only unlock, to avoid deadlock. */ + spin_unlock(&dev->lock); + value = usb_ep_queue(dev->in_ep, req, GFP_ATOMIC); + spin_lock(&dev->lock); + if (value) { + list_move(&req->list, &dev->tx_reqs); + spin_unlock_irqrestore(&dev->lock, flags); + mutex_unlock(&dev->lock_printer_io); + return -EAGAIN; + } + } + + spin_unlock_irqrestore(&dev->lock, flags); + mutex_unlock(&dev->lock_printer_io); + + DBG(dev, "printer_write sent %d bytes\n", (int)bytes_copied); + + if (bytes_copied) + return bytes_copied; + else + return -EAGAIN; +} + +static int +printer_fsync(struct file *fd, loff_t start, loff_t end, int datasync) +{ + struct printer_dev *dev = fd->private_data; + struct inode *inode = file_inode(fd); + unsigned long flags; + int tx_list_empty; + + inode_lock(inode); + spin_lock_irqsave(&dev->lock, flags); + + if (dev->interface < 0) { + spin_unlock_irqrestore(&dev->lock, flags); + inode_unlock(inode); + return -ENODEV; + } + + tx_list_empty = (likely(list_empty(&dev->tx_reqs))); + spin_unlock_irqrestore(&dev->lock, flags); + + if (!tx_list_empty) { + /* Sleep until all data has been sent */ + wait_event_interruptible(dev->tx_flush_wait, + (likely(list_empty(&dev->tx_reqs_active)))); + } + inode_unlock(inode); + + return 0; +} + +static __poll_t +printer_poll(struct file *fd, poll_table *wait) +{ + struct printer_dev *dev = fd->private_data; + unsigned long flags; + __poll_t status = 0; + + mutex_lock(&dev->lock_printer_io); + spin_lock_irqsave(&dev->lock, flags); + + if (dev->interface < 0) { + spin_unlock_irqrestore(&dev->lock, flags); + mutex_unlock(&dev->lock_printer_io); + return EPOLLERR | EPOLLHUP; + } + + setup_rx_reqs(dev); + spin_unlock_irqrestore(&dev->lock, flags); + mutex_unlock(&dev->lock_printer_io); + + poll_wait(fd, &dev->rx_wait, wait); + poll_wait(fd, &dev->tx_wait, wait); + + spin_lock_irqsave(&dev->lock, flags); + if (likely(!list_empty(&dev->tx_reqs))) + status |= EPOLLOUT | EPOLLWRNORM; + + if (likely(dev->current_rx_bytes) || + likely(!list_empty(&dev->rx_buffers))) + status |= EPOLLIN | EPOLLRDNORM; + + spin_unlock_irqrestore(&dev->lock, flags); + + return status; +} + +static long +printer_ioctl(struct file *fd, unsigned int code, unsigned long arg) +{ + struct printer_dev *dev = fd->private_data; + unsigned long flags; + int status = 0; + + DBG(dev, "printer_ioctl: cmd=0x%4.4x, arg=%lu\n", code, arg); + + /* handle ioctls */ + + spin_lock_irqsave(&dev->lock, flags); + + if (dev->interface < 0) { + spin_unlock_irqrestore(&dev->lock, flags); + return -ENODEV; + } + + switch (code) { + case GADGET_GET_PRINTER_STATUS: + status = (int)dev->printer_status; + break; + case GADGET_SET_PRINTER_STATUS: + dev->printer_status = (u8)arg; + break; + default: + /* could not handle ioctl */ + DBG(dev, "printer_ioctl: ERROR cmd=0x%4.4xis not supported\n", + code); + status = -ENOTTY; + } + + spin_unlock_irqrestore(&dev->lock, flags); + + return status; +} + +/* used after endpoint configuration */ +static const struct file_operations printer_io_operations = { + .owner = THIS_MODULE, + .open = printer_open, + .read = printer_read, + .write = printer_write, + .fsync = printer_fsync, + .poll = printer_poll, + .unlocked_ioctl = printer_ioctl, + .release = printer_close, + .llseek = noop_llseek, +}; + +/*-------------------------------------------------------------------------*/ + +static int +set_printer_interface(struct printer_dev *dev) +{ + int result = 0; + + dev->in_ep->desc = ep_desc(dev->gadget, &fs_ep_in_desc, &hs_ep_in_desc, + &ss_ep_in_desc); + dev->in_ep->driver_data = dev; + + dev->out_ep->desc = ep_desc(dev->gadget, &fs_ep_out_desc, + &hs_ep_out_desc, &ss_ep_out_desc); + dev->out_ep->driver_data = dev; + + result = usb_ep_enable(dev->in_ep); + if (result != 0) { + DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result); + goto done; + } + + result = usb_ep_enable(dev->out_ep); + if (result != 0) { + DBG(dev, "enable %s --> %d\n", dev->out_ep->name, result); + goto done; + } + +done: + /* on error, disable any endpoints */ + if (result != 0) { + (void) usb_ep_disable(dev->in_ep); + (void) usb_ep_disable(dev->out_ep); + dev->in_ep->desc = NULL; + dev->out_ep->desc = NULL; + } + + /* caller is responsible for cleanup on error */ + return result; +} + +static void printer_reset_interface(struct printer_dev *dev) +{ + unsigned long flags; + + if (dev->interface < 0) + return; + + DBG(dev, "%s\n", __func__); + + if (dev->in_ep->desc) + usb_ep_disable(dev->in_ep); + + if (dev->out_ep->desc) + usb_ep_disable(dev->out_ep); + + spin_lock_irqsave(&dev->lock, flags); + dev->in_ep->desc = NULL; + dev->out_ep->desc = NULL; + dev->interface = -1; + spin_unlock_irqrestore(&dev->lock, flags); +} + +/* Change our operational Interface. */ +static int set_interface(struct printer_dev *dev, unsigned number) +{ + int result = 0; + + /* Free the current interface */ + printer_reset_interface(dev); + + result = set_printer_interface(dev); + if (result) + printer_reset_interface(dev); + else + dev->interface = number; + + if (!result) + INFO(dev, "Using interface %x\n", number); + + return result; +} + +static void printer_soft_reset(struct printer_dev *dev) +{ + struct usb_request *req; + + INFO(dev, "Received Printer Reset Request\n"); + + if (usb_ep_disable(dev->in_ep)) + DBG(dev, "Failed to disable USB in_ep\n"); + if (usb_ep_disable(dev->out_ep)) + DBG(dev, "Failed to disable USB out_ep\n"); + + if (dev->current_rx_req != NULL) { + list_add(&dev->current_rx_req->list, &dev->rx_reqs); + dev->current_rx_req = NULL; + } + dev->current_rx_bytes = 0; + dev->current_rx_buf = NULL; + dev->reset_printer = 1; + + while (likely(!(list_empty(&dev->rx_buffers)))) { + req = container_of(dev->rx_buffers.next, struct usb_request, + list); + list_del_init(&req->list); + list_add(&req->list, &dev->rx_reqs); + } + + while (likely(!(list_empty(&dev->rx_reqs_active)))) { + req = container_of(dev->rx_buffers.next, struct usb_request, + list); + list_del_init(&req->list); + list_add(&req->list, &dev->rx_reqs); + } + + while (likely(!(list_empty(&dev->tx_reqs_active)))) { + req = container_of(dev->tx_reqs_active.next, + struct usb_request, list); + list_del_init(&req->list); + list_add(&req->list, &dev->tx_reqs); + } + + if (usb_ep_enable(dev->in_ep)) + DBG(dev, "Failed to enable USB in_ep\n"); + if (usb_ep_enable(dev->out_ep)) + DBG(dev, "Failed to enable USB out_ep\n"); + + wake_up_interruptible(&dev->rx_wait); + wake_up_interruptible(&dev->tx_wait); + wake_up_interruptible(&dev->tx_flush_wait); +} + +/*-------------------------------------------------------------------------*/ + +static bool gprinter_req_match(struct usb_function *f, + const struct usb_ctrlrequest *ctrl, + bool config0) +{ + struct printer_dev *dev = func_to_printer(f); + u16 w_index = le16_to_cpu(ctrl->wIndex); + u16 w_value = le16_to_cpu(ctrl->wValue); + u16 w_length = le16_to_cpu(ctrl->wLength); + + if (config0) + return false; + + if ((ctrl->bRequestType & USB_RECIP_MASK) != USB_RECIP_INTERFACE || + (ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS) + return false; + + switch (ctrl->bRequest) { + case GET_DEVICE_ID: + w_index >>= 8; + if (USB_DIR_IN & ctrl->bRequestType) + break; + return false; + case GET_PORT_STATUS: + if (!w_value && w_length == 1 && + (USB_DIR_IN & ctrl->bRequestType)) + break; + return false; + case SOFT_RESET: + if (!w_value && !w_length && + !(USB_DIR_IN & ctrl->bRequestType)) + break; + fallthrough; + default: + return false; + } + return w_index == dev->interface; +} + +/* + * The setup() callback implements all the ep0 functionality that's not + * handled lower down. + */ +static int printer_func_setup(struct usb_function *f, + const struct usb_ctrlrequest *ctrl) +{ + struct printer_dev *dev = func_to_printer(f); + struct usb_composite_dev *cdev = f->config->cdev; + struct usb_request *req = cdev->req; + u8 *buf = req->buf; + int value = -EOPNOTSUPP; + u16 wIndex = le16_to_cpu(ctrl->wIndex); + u16 wValue = le16_to_cpu(ctrl->wValue); + u16 wLength = le16_to_cpu(ctrl->wLength); + + DBG(dev, "ctrl req%02x.%02x v%04x i%04x l%d\n", + ctrl->bRequestType, ctrl->bRequest, wValue, wIndex, wLength); + + switch (ctrl->bRequestType&USB_TYPE_MASK) { + case USB_TYPE_CLASS: + switch (ctrl->bRequest) { + case GET_DEVICE_ID: /* Get the IEEE-1284 PNP String */ + /* Only one printer interface is supported. */ + if ((wIndex>>8) != dev->interface) + break; + + if (!*dev->pnp_string) { + value = 0; + break; + } + value = strlen(*dev->pnp_string); + buf[0] = (value >> 8) & 0xFF; + buf[1] = value & 0xFF; + memcpy(buf + 2, *dev->pnp_string, value); + DBG(dev, "1284 PNP String: %x %s\n", value, + *dev->pnp_string); + break; + + case GET_PORT_STATUS: /* Get Port Status */ + /* Only one printer interface is supported. */ + if (wIndex != dev->interface) + break; + + buf[0] = dev->printer_status; + value = min_t(u16, wLength, 1); + break; + + case SOFT_RESET: /* Soft Reset */ + /* Only one printer interface is supported. */ + if (wIndex != dev->interface) + break; + + printer_soft_reset(dev); + + value = 0; + break; + + default: + goto unknown; + } + break; + + default: +unknown: + VDBG(dev, + "unknown ctrl req%02x.%02x v%04x i%04x l%d\n", + ctrl->bRequestType, ctrl->bRequest, + wValue, wIndex, wLength); + break; + } + /* host either stalls (value < 0) or reports success */ + if (value >= 0) { + req->length = value; + req->zero = value < wLength; + value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC); + if (value < 0) { + ERROR(dev, "%s:%d Error!\n", __func__, __LINE__); + req->status = 0; + } + } + return value; +} + +static int printer_func_bind(struct usb_configuration *c, + struct usb_function *f) +{ + struct usb_gadget *gadget = c->cdev->gadget; + struct printer_dev *dev = func_to_printer(f); + struct device *pdev; + struct usb_composite_dev *cdev = c->cdev; + struct usb_ep *in_ep; + struct usb_ep *out_ep = NULL; + struct usb_request *req; + dev_t devt; + int id; + int ret; + u32 i; + + id = usb_interface_id(c, f); + if (id < 0) + return id; + intf_desc.bInterfaceNumber = id; + + /* finish hookup to lower layer ... */ + dev->gadget = gadget; + + /* all we really need is bulk IN/OUT */ + in_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_in_desc); + if (!in_ep) { +autoconf_fail: + dev_err(&cdev->gadget->dev, "can't autoconfigure on %s\n", + cdev->gadget->name); + return -ENODEV; + } + + out_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_out_desc); + if (!out_ep) + goto autoconf_fail; + + /* assumes that all endpoints are dual-speed */ + hs_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress; + hs_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress; + ss_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress; + ss_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress; + + ret = usb_assign_descriptors(f, fs_printer_function, + hs_printer_function, ss_printer_function, + ss_printer_function); + if (ret) + return ret; + + dev->in_ep = in_ep; + dev->out_ep = out_ep; + + ret = -ENOMEM; + for (i = 0; i < dev->q_len; i++) { + req = printer_req_alloc(dev->in_ep, USB_BUFSIZE, GFP_KERNEL); + if (!req) + goto fail_tx_reqs; + list_add(&req->list, &dev->tx_reqs); + } + + for (i = 0; i < dev->q_len; i++) { + req = printer_req_alloc(dev->out_ep, USB_BUFSIZE, GFP_KERNEL); + if (!req) + goto fail_rx_reqs; + list_add(&req->list, &dev->rx_reqs); + } + + /* Setup the sysfs files for the printer gadget. */ + devt = MKDEV(major, dev->minor); + pdev = device_create(usb_gadget_class, NULL, devt, + NULL, "g_printer%d", dev->minor); + if (IS_ERR(pdev)) { + ERROR(dev, "Failed to create device: g_printer\n"); + ret = PTR_ERR(pdev); + goto fail_rx_reqs; + } + + /* + * Register a character device as an interface to a user mode + * program that handles the printer specific functionality. + */ + cdev_init(&dev->printer_cdev, &printer_io_operations); + dev->printer_cdev.owner = THIS_MODULE; + ret = cdev_add(&dev->printer_cdev, devt, 1); + if (ret) { + ERROR(dev, "Failed to open char device\n"); + goto fail_cdev_add; + } + + return 0; + +fail_cdev_add: + device_destroy(usb_gadget_class, devt); + +fail_rx_reqs: + while (!list_empty(&dev->rx_reqs)) { + req = container_of(dev->rx_reqs.next, struct usb_request, list); + list_del(&req->list); + printer_req_free(dev->out_ep, req); + } + +fail_tx_reqs: + while (!list_empty(&dev->tx_reqs)) { + req = container_of(dev->tx_reqs.next, struct usb_request, list); + list_del(&req->list); + printer_req_free(dev->in_ep, req); + } + + usb_free_all_descriptors(f); + return ret; + +} + +static int printer_func_set_alt(struct usb_function *f, + unsigned intf, unsigned alt) +{ + struct printer_dev *dev = func_to_printer(f); + int ret = -ENOTSUPP; + + if (!alt) + ret = set_interface(dev, intf); + + return ret; +} + +static void printer_func_disable(struct usb_function *f) +{ + struct printer_dev *dev = func_to_printer(f); + + DBG(dev, "%s\n", __func__); + + printer_reset_interface(dev); +} + +static inline struct f_printer_opts +*to_f_printer_opts(struct config_item *item) +{ + return container_of(to_config_group(item), struct f_printer_opts, + func_inst.group); +} + +static void printer_attr_release(struct config_item *item) +{ + struct f_printer_opts *opts = to_f_printer_opts(item); + + usb_put_function_instance(&opts->func_inst); +} + +static struct configfs_item_operations printer_item_ops = { + .release = printer_attr_release, +}; + +static ssize_t f_printer_opts_pnp_string_show(struct config_item *item, + char *page) +{ + struct f_printer_opts *opts = to_f_printer_opts(item); + int result = 0; + + mutex_lock(&opts->lock); + if (!opts->pnp_string) + goto unlock; + + result = strlcpy(page, opts->pnp_string, PAGE_SIZE); + if (result >= PAGE_SIZE) { + result = PAGE_SIZE; + } else if (page[result - 1] != '\n' && result + 1 < PAGE_SIZE) { + page[result++] = '\n'; + page[result] = '\0'; + } + +unlock: + mutex_unlock(&opts->lock); + + return result; +} + +static ssize_t f_printer_opts_pnp_string_store(struct config_item *item, + const char *page, size_t len) +{ + struct f_printer_opts *opts = to_f_printer_opts(item); + char *new_pnp; + int result; + + mutex_lock(&opts->lock); + + new_pnp = kstrndup(page, len, GFP_KERNEL); + if (!new_pnp) { + result = -ENOMEM; + goto unlock; + } + + if (opts->pnp_string_allocated) + kfree(opts->pnp_string); + + opts->pnp_string_allocated = true; + opts->pnp_string = new_pnp; + result = len; +unlock: + mutex_unlock(&opts->lock); + + return result; +} + +CONFIGFS_ATTR(f_printer_opts_, pnp_string); + +static ssize_t f_printer_opts_q_len_show(struct config_item *item, + char *page) +{ + struct f_printer_opts *opts = to_f_printer_opts(item); + int result; + + mutex_lock(&opts->lock); + result = sprintf(page, "%d\n", opts->q_len); + mutex_unlock(&opts->lock); + + return result; +} + +static ssize_t f_printer_opts_q_len_store(struct config_item *item, + const char *page, size_t len) +{ + struct f_printer_opts *opts = to_f_printer_opts(item); + int ret; + u16 num; + + mutex_lock(&opts->lock); + if (opts->refcnt) { + ret = -EBUSY; + goto end; + } + + ret = kstrtou16(page, 0, &num); + if (ret) + goto end; + + opts->q_len = (unsigned)num; + ret = len; +end: + mutex_unlock(&opts->lock); + return ret; +} + +CONFIGFS_ATTR(f_printer_opts_, q_len); + +static struct configfs_attribute *printer_attrs[] = { + &f_printer_opts_attr_pnp_string, + &f_printer_opts_attr_q_len, + NULL, +}; + +static const struct config_item_type printer_func_type = { + .ct_item_ops = &printer_item_ops, + .ct_attrs = printer_attrs, + .ct_owner = THIS_MODULE, +}; + +static inline int gprinter_get_minor(void) +{ + int ret; + + ret = ida_simple_get(&printer_ida, 0, 0, GFP_KERNEL); + if (ret >= PRINTER_MINORS) { + ida_simple_remove(&printer_ida, ret); + ret = -ENODEV; + } + + return ret; +} + +static inline void gprinter_put_minor(int minor) +{ + ida_simple_remove(&printer_ida, minor); +} + +static int gprinter_setup(int); +static void gprinter_cleanup(void); + +static void gprinter_free_inst(struct usb_function_instance *f) +{ + struct f_printer_opts *opts; + + opts = container_of(f, struct f_printer_opts, func_inst); + + mutex_lock(&printer_ida_lock); + + gprinter_put_minor(opts->minor); + if (ida_is_empty(&printer_ida)) + gprinter_cleanup(); + + mutex_unlock(&printer_ida_lock); + + if (opts->pnp_string_allocated) + kfree(opts->pnp_string); + kfree(opts); +} + +static struct usb_function_instance *gprinter_alloc_inst(void) +{ + struct f_printer_opts *opts; + struct usb_function_instance *ret; + int status = 0; + + opts = kzalloc(sizeof(*opts), GFP_KERNEL); + if (!opts) + return ERR_PTR(-ENOMEM); + + mutex_init(&opts->lock); + opts->func_inst.free_func_inst = gprinter_free_inst; + ret = &opts->func_inst; + + /* Make sure q_len is initialized, otherwise the bound device can't support read/write! */ + opts->q_len = DEFAULT_Q_LEN; + + mutex_lock(&printer_ida_lock); + + if (ida_is_empty(&printer_ida)) { + status = gprinter_setup(PRINTER_MINORS); + if (status) { + ret = ERR_PTR(status); + kfree(opts); + goto unlock; + } + } + + opts->minor = gprinter_get_minor(); + if (opts->minor < 0) { + ret = ERR_PTR(opts->minor); + kfree(opts); + if (ida_is_empty(&printer_ida)) + gprinter_cleanup(); + goto unlock; + } + config_group_init_type_name(&opts->func_inst.group, "", + &printer_func_type); + +unlock: + mutex_unlock(&printer_ida_lock); + return ret; +} + +static void gprinter_free(struct usb_function *f) +{ + struct printer_dev *dev = func_to_printer(f); + struct f_printer_opts *opts; + + opts = container_of(f->fi, struct f_printer_opts, func_inst); + + kref_put(&dev->kref, printer_dev_free); + mutex_lock(&opts->lock); + --opts->refcnt; + mutex_unlock(&opts->lock); +} + +static void printer_func_unbind(struct usb_configuration *c, + struct usb_function *f) +{ + struct printer_dev *dev; + struct usb_request *req; + + dev = func_to_printer(f); + + device_destroy(usb_gadget_class, MKDEV(major, dev->minor)); + + /* Remove Character Device */ + cdev_del(&dev->printer_cdev); + + /* we must already have been disconnected ... no i/o may be active */ + WARN_ON(!list_empty(&dev->tx_reqs_active)); + WARN_ON(!list_empty(&dev->rx_reqs_active)); + + /* Free all memory for this driver. */ + while (!list_empty(&dev->tx_reqs)) { + req = container_of(dev->tx_reqs.next, struct usb_request, + list); + list_del(&req->list); + printer_req_free(dev->in_ep, req); + } + + if (dev->current_rx_req != NULL) + printer_req_free(dev->out_ep, dev->current_rx_req); + + while (!list_empty(&dev->rx_reqs)) { + req = container_of(dev->rx_reqs.next, + struct usb_request, list); + list_del(&req->list); + printer_req_free(dev->out_ep, req); + } + + while (!list_empty(&dev->rx_buffers)) { + req = container_of(dev->rx_buffers.next, + struct usb_request, list); + list_del(&req->list); + printer_req_free(dev->out_ep, req); + } + usb_free_all_descriptors(f); +} + +static struct usb_function *gprinter_alloc(struct usb_function_instance *fi) +{ + struct printer_dev *dev; + struct f_printer_opts *opts; + + opts = container_of(fi, struct f_printer_opts, func_inst); + + mutex_lock(&opts->lock); + if (opts->minor >= minors) { + mutex_unlock(&opts->lock); + return ERR_PTR(-ENOENT); + } + + dev = kzalloc(sizeof(*dev), GFP_KERNEL); + if (!dev) { + mutex_unlock(&opts->lock); + return ERR_PTR(-ENOMEM); + } + + kref_init(&dev->kref); + ++opts->refcnt; + dev->minor = opts->minor; + dev->pnp_string = &opts->pnp_string; + dev->q_len = opts->q_len; + mutex_unlock(&opts->lock); + + dev->function.name = "printer"; + dev->function.bind = printer_func_bind; + dev->function.setup = printer_func_setup; + dev->function.unbind = printer_func_unbind; + dev->function.set_alt = printer_func_set_alt; + dev->function.disable = printer_func_disable; + dev->function.req_match = gprinter_req_match; + dev->function.free_func = gprinter_free; + + INIT_LIST_HEAD(&dev->tx_reqs); + INIT_LIST_HEAD(&dev->rx_reqs); + INIT_LIST_HEAD(&dev->rx_buffers); + INIT_LIST_HEAD(&dev->tx_reqs_active); + INIT_LIST_HEAD(&dev->rx_reqs_active); + + spin_lock_init(&dev->lock); + mutex_init(&dev->lock_printer_io); + init_waitqueue_head(&dev->rx_wait); + init_waitqueue_head(&dev->tx_wait); + init_waitqueue_head(&dev->tx_flush_wait); + + dev->interface = -1; + dev->printer_cdev_open = 0; + dev->printer_status = PRINTER_NOT_ERROR; + dev->current_rx_req = NULL; + dev->current_rx_bytes = 0; + dev->current_rx_buf = NULL; + + return &dev->function; +} + +DECLARE_USB_FUNCTION_INIT(printer, gprinter_alloc_inst, gprinter_alloc); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Craig Nadler"); + +static int gprinter_setup(int count) +{ + int status; + dev_t devt; + + usb_gadget_class = class_create(THIS_MODULE, "usb_printer_gadget"); + if (IS_ERR(usb_gadget_class)) { + status = PTR_ERR(usb_gadget_class); + usb_gadget_class = NULL; + pr_err("unable to create usb_gadget class %d\n", status); + return status; + } + + status = alloc_chrdev_region(&devt, 0, count, "USB printer gadget"); + if (status) { + pr_err("alloc_chrdev_region %d\n", status); + class_destroy(usb_gadget_class); + usb_gadget_class = NULL; + return status; + } + + major = MAJOR(devt); + minors = count; + + return status; +} + +static void gprinter_cleanup(void) +{ + if (major) { + unregister_chrdev_region(MKDEV(major, 0), minors); + major = minors = 0; + } + class_destroy(usb_gadget_class); + usb_gadget_class = NULL; +} |