// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2015 Karol Kosik <[email protected]>
* Copyright (C) 2015-2016 Samsung Electronics
* Igor Kotrasinski <[email protected]>
* Krzysztof Opasiak <[email protected]>
*/
#include <linux/device.h>
#include <linux/list.h>
#include <linux/usb/gadget.h>
#include <linux/usb/ch9.h>
#include <linux/sysfs.h>
#include <linux/kthread.h>
#include <linux/byteorder/generic.h>
#include "usbip_common.h"
#include "vudc.h"
#include <net/sock.h>
/* called with udc->lock held */
int get_gadget_descs(struct vudc *udc)
{
struct vrequest *usb_req;
struct vep *ep0 = to_vep(udc->gadget.ep0);
struct usb_device_descriptor *ddesc = &udc->dev_desc;
struct usb_ctrlrequest req;
int ret;
if (!udc->driver || !udc->pullup)
return -EINVAL;
req.bRequestType = USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE;
req.bRequest = USB_REQ_GET_DESCRIPTOR;
req.wValue = cpu_to_le16(USB_DT_DEVICE << 8);
req.wIndex = cpu_to_le16(0);
req.wLength = cpu_to_le16(sizeof(*ddesc));
spin_unlock(&udc->lock);
ret = udc->driver->setup(&(udc->gadget), &req);
spin_lock(&udc->lock);
if (ret < 0)
goto out;
/* assuming request queue is empty; request is now on top */
usb_req = list_last_entry(&ep0->req_queue, struct vrequest, req_entry);
list_del(&usb_req->req_entry);
if (usb_req->req.length > sizeof(*ddesc)) {
ret = -EOVERFLOW;
goto giveback_req;
}
memcpy(ddesc, usb_req->req.buf, sizeof(*ddesc));
udc->desc_cached = 1;
ret = 0;
giveback_req:
usb_req->req.status = 0;
usb_req->req.actual = usb_req->req.length;
usb_gadget_giveback_request(&(ep0->ep), &(usb_req->req));
out:
return ret;
}
/*
* Exposes device descriptor from the gadget driver.
*/
static ssize_t dev_desc_read(struct file *file, struct kobject *kobj,
struct bin_attribute *attr, char *out,
loff_t off, size_t count)
{
struct device *dev = kobj_to_dev(kobj);
struct vudc *udc = (struct vudc *)dev_get_drvdata(dev);
char *desc_ptr = (char *) &udc->dev_desc;
unsigned long flags;
int ret;
spin_lock_irqsave(&udc->lock, flags);
if (!udc->desc_cached) {
ret = -ENODEV;
goto unlock;
}
memcpy(out, desc_ptr + off, count);
ret = count;
unlock:
spin_unlock_irqrestore(&udc->lock, flags);
return ret;
}
static BIN_ATTR_RO(dev_desc, sizeof(struct usb_device_descriptor));
static ssize_t usbip_sockfd_store(struct device *dev,
struct device_attribute *attr,
const char *in, size_t count)
{
struct vudc *udc = (struct vudc *) dev_get_drvdata(dev);
int rv;
int sockfd = 0;
int err;
struct socket *socket;
unsigned long flags;
int ret;
struct task_struct *tcp_rx = NULL;
struct task_struct *tcp_tx = NULL;
rv = kstrtoint(in, 0, &sockfd);
if (rv != 0)
return -EINVAL;
if (!udc) {
dev_err(dev, "no device");
return -ENODEV;
}
mutex_lock(&udc->ud.sysfs_lock);
spin_lock_irqsave(&udc->lock, flags);
/* Don't export what we don't have */
if (!udc->driver || !udc->pullup) {
dev_err(dev, "gadget not bound");
ret = -ENODEV;
goto unlock;
}
if (sockfd != -1) {
if (udc->connected) {
dev_err(dev, "Device already connected");
ret = -EBUSY;
goto unlock;
}
spin_lock(&udc->ud.lock);
if (udc->ud.status != SDEV_ST_AVAILABLE) {
ret = -EINVAL;
goto unlock_ud;
}
socket = sockfd_lookup(sockfd, &err);
if (!socket) {
dev_err(dev, "failed to lookup sock");
ret = -EINVAL;
goto unlock_ud;
}
if (socket->type != SOCK_STREAM) {
dev_err(dev, "Expecting SOCK_STREAM - found %d",
socket->type);
ret = -EINVAL;
goto sock_err;
}
/* unlock and create threads and get tasks */
spin_unlock(&udc->ud.lock);
spin_unlock_irqrestore(&udc->lock, flags);
tcp_rx = kthread_create(&v_rx_loop, &udc->ud, "vudc_rx");
if (IS_ERR(tcp_rx)) {
sockfd_put(socket);
mutex_unlock(&udc->ud.sysfs_lock);
return -EINVAL;
}
tcp_tx = kthread_create(&v_tx_loop, &udc->ud, "vudc_tx");
if (IS_ERR(tcp_tx)) {
kthread_stop(tcp_rx);
sockfd_put(socket);
mutex_unlock(&udc->ud.sysfs_lock);
return -EINVAL;
}
/* get task structs now */
get_task_struct(tcp_rx);
get_task_struct(tcp_tx);
/* lock and update udc->ud state */
spin_lock_irqsave(&udc->lock, flags);
spin_lock(&udc->ud.lock);
udc->ud.tcp_socket = socket;
udc->ud.tcp_rx = tcp_rx;
udc->ud.tcp_tx = tcp_tx;
udc->ud.status = SDEV_ST_USED;
spin_unlock(&udc->ud.lock);
ktime_get_ts64(&udc->start_time);
v_start_timer(udc);
udc->connected = 1;
spin_unlock_irqrestore(&udc->lock, flags);
wake_up_process(udc->ud.tcp_rx);
wake_up_process(udc->ud.tcp_tx);
mutex_unlock(&udc->ud.sysfs_lock);
return count;
} else {
if (!udc->connected) {
dev_err(dev, "Device not connected");
ret = -EINVAL;
goto unlock;
}
spin_lock(&udc->ud.lock);
if (udc->ud.status != SDEV_ST_USED) {
ret = -EINVAL;
goto unlock_ud;
}
spin_unlock(&udc->ud.lock);
usbip_event_add(&udc->ud, VUDC_EVENT_DOWN);
}
spin_unlock_irqrestore(&udc->lock, flags);
mutex_unlock(&udc->ud.sysfs_lock);
return count;
sock_err:
sockfd_put(socket);
unlock_ud:
spin_unlock(&udc->ud.lock);
unlock:
spin_unlock_irqrestore(&udc->lock, flags);
mutex_unlock(&udc->ud.sysfs_lock);
return ret;
}
static DEVICE_ATTR_WO(usbip_sockfd);
static ssize_t usbip_status_show(struct device *dev,
struct device_attribute *attr, char *out)
{
struct vudc *udc = (struct vudc *) dev_get_drvdata(dev);
int status;
if (!udc) {
dev_err(dev, "no device");
return -ENODEV;
}
spin_lock_irq(&udc->ud.lock);
status = udc->ud.status;
spin_unlock_irq(&udc->ud.lock);
return sysfs_emit(out, "%d\n", status);
}
static DEVICE_ATTR_RO(usbip_status);
static struct attribute *dev_attrs[] = {
&dev_attr_usbip_sockfd.attr,
&dev_attr_usbip_status.attr,
NULL,
};
static struct bin_attribute *dev_bin_attrs[] = {
&bin_attr_dev_desc,
NULL,
};
static const struct attribute_group vudc_attr_group = {
.attrs = dev_attrs,
.bin_attrs = dev_bin_attrs,
};
const struct attribute_group *vudc_groups[] = {
&vudc_attr_group,
NULL,
};
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