drivers/usb/usbip/vudc_sysfs.c

   1 /*
   2  * Copyright (C) 2015 Karol Kosik <karo9@interia.eu>
   3  * Copyright (C) 2015-2016 Samsung Electronics
   4  *               Igor Kotrasinski <i.kotrasinsk@samsung.com>
   5  *               Krzysztof Opasiak <k.opasiak@samsung.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <linux/device.h>
  22 #include <linux/list.h>
  23 #include <linux/usb/gadget.h>
  24 #include <linux/usb/ch9.h>
  25 #include <linux/sysfs.h>
  26 #include <linux/kthread.h>
  27 #include <linux/byteorder/generic.h>
  28
  29 #include "usbip_common.h"
  30 #include "vudc.h"
  31
  32 #include <net/sock.h>
  33
  34 /* called with udc->lock held */
  35 int get_gadget_descs(struct vudc *udc)
  36 {
  37         struct vrequest *usb_req;
  38         struct vep *ep0 = to_vep(udc->gadget.ep0);
  39         struct usb_device_descriptor *ddesc = &udc->dev_desc;
  40         struct usb_ctrlrequest req;
  41         int ret;
  42
  43         if (!udc->driver || !udc->pullup)
  44                 return -EINVAL;
  45
  46         req.bRequestType = USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE;
  47         req.bRequest = USB_REQ_GET_DESCRIPTOR;
  48         req.wValue = cpu_to_le16(USB_DT_DEVICE << 8);
  49         req.wIndex = cpu_to_le16(0);
  50         req.wLength = cpu_to_le16(sizeof(*ddesc));
  51
  52         spin_unlock(&udc->lock);
  53         ret = udc->driver->setup(&(udc->gadget), &req);
  54         spin_lock(&udc->lock);
  55         if (ret < 0)
  56                 goto out;
  57
  58         /* assuming request queue is empty; request is now on top */
  59         usb_req = list_last_entry(&ep0->req_queue, struct vrequest, req_entry);
  60         list_del(&usb_req->req_entry);
  61
  62         if (usb_req->req.length > sizeof(*ddesc)) {
  63                 ret = -EOVERFLOW;
  64                 goto giveback_req;
  65         }
  66
  67         memcpy(ddesc, usb_req->req.buf, sizeof(*ddesc));
  68         udc->desc_cached = 1;
  69         ret = 0;
  70 giveback_req:
  71         usb_req->req.status = 0;
  72         usb_req->req.actual = usb_req->req.length;
  73         usb_gadget_giveback_request(&(ep0->ep), &(usb_req->req));
  74 out:
  75         return ret;
  76 }
  77
  78 /*
  79  * Exposes device descriptor from the gadget driver.
  80  */
  81 static ssize_t dev_desc_read(struct file *file, struct kobject *kobj,
  82                              struct bin_attribute *attr, char *out,
  83                              loff_t off, size_t count)
  84 {
  85         struct device *dev = kobj_to_dev(kobj);
  86         struct vudc *udc = (struct vudc *)dev_get_drvdata(dev);
  87         char *desc_ptr = (char *) &udc->dev_desc;
  88         unsigned long flags;
  89         int ret;
  90
  91         spin_lock_irqsave(&udc->lock, flags);
  92         if (!udc->desc_cached) {
  93                 ret = -ENODEV;
  94                 goto unlock;
  95         }
  96
  97         memcpy(out, desc_ptr + off, count);
  98         ret = count;
  99 unlock:
 100         spin_unlock_irqrestore(&udc->lock, flags);
 101         return ret;
 102 }
 103 static BIN_ATTR_RO(dev_desc, sizeof(struct usb_device_descriptor));
 104
 105 static ssize_t store_sockfd(struct device *dev, struct device_attribute *attr,
 106                      const char *in, size_t count)
 107 {
 108         struct vudc *udc = (struct vudc *) dev_get_drvdata(dev);
 109         int rv;
 110         int sockfd = 0;
 111         int err;
 112         struct socket *socket;
 113         unsigned long flags;
 114         int ret;
 115
 116         rv = kstrtoint(in, 0, &sockfd);
 117         if (rv != 0)
 118                 return -EINVAL;
 119
 120         if (!udc) {
 121                 dev_err(dev, "no device");
 122                 return -ENODEV;
 123         }
 124         spin_lock_irqsave(&udc->lock, flags);
 125         /* Don't export what we don't have */
 126         if (!udc->driver || !udc->pullup) {
 127                 dev_err(dev, "gadget not bound");
 128                 ret = -ENODEV;
 129                 goto unlock;
 130         }
 131
 132         if (sockfd != -1) {
 133                 if (udc->connected) {
 134                         dev_err(dev, "Device already connected");
 135                         ret = -EBUSY;
 136                         goto unlock;
 137                 }
 138
 139                 spin_lock_irq(&udc->ud.lock);
 140
 141                 if (udc->ud.status != SDEV_ST_AVAILABLE) {
 142                         ret = -EINVAL;
 143                         goto unlock_ud;
 144                 }
 145
 146                 socket = sockfd_lookup(sockfd, &err);
 147                 if (!socket) {
 148                         dev_err(dev, "failed to lookup sock");
 149                         ret = -EINVAL;
 150                         goto unlock_ud;
 151                 }
 152
 153                 udc->ud.tcp_socket = socket;
 154
 155                 spin_unlock_irq(&udc->ud.lock);
 156                 spin_unlock_irqrestore(&udc->lock, flags);
 157
 158                 udc->ud.tcp_rx = kthread_get_run(&v_rx_loop,
 159                                                     &udc->ud, "vudc_rx");
 160                 udc->ud.tcp_tx = kthread_get_run(&v_tx_loop,
 161                                                     &udc->ud, "vudc_tx");
 162
 163                 spin_lock_irqsave(&udc->lock, flags);
 164                 spin_lock_irq(&udc->ud.lock);
 165                 udc->ud.status = SDEV_ST_USED;
 166                 spin_unlock_irq(&udc->ud.lock);
 167
 168                 do_gettimeofday(&udc->start_time);
 169                 v_start_timer(udc);
 170                 udc->connected = 1;
 171         } else {
 172                 if (!udc->connected) {
 173                         dev_err(dev, "Device not connected");
 174                         ret = -EINVAL;
 175                         goto unlock;
 176                 }
 177
 178                 spin_lock_irq(&udc->ud.lock);
 179                 if (udc->ud.status != SDEV_ST_USED) {
 180                         ret = -EINVAL;
 181                         goto unlock_ud;
 182                 }
 183                 spin_unlock_irq(&udc->ud.lock);
 184
 185                 usbip_event_add(&udc->ud, VUDC_EVENT_DOWN);
 186         }
 187
 188         spin_unlock_irqrestore(&udc->lock, flags);
 189
 190         return count;
 191
 192 unlock_ud:
 193         spin_unlock_irq(&udc->ud.lock);
 194 unlock:
 195         spin_unlock_irqrestore(&udc->lock, flags);
 196
 197         return ret;
 198 }
 199 static DEVICE_ATTR(usbip_sockfd, S_IWUSR, NULL, store_sockfd);
 200
 201 static ssize_t usbip_status_show(struct device *dev,
 202                                struct device_attribute *attr, char *out)
 203 {
 204         struct vudc *udc = (struct vudc *) dev_get_drvdata(dev);
 205         int status;
 206
 207         if (!udc) {
 208                 dev_err(dev, "no device");
 209                 return -ENODEV;
 210         }
 211         spin_lock_irq(&udc->ud.lock);
 212         status = udc->ud.status;
 213         spin_unlock_irq(&udc->ud.lock);
 214
 215         return snprintf(out, PAGE_SIZE, "%d\n", status);
 216 }
 217 static DEVICE_ATTR_RO(usbip_status);
 218
 219 static struct attribute *dev_attrs[] = {
 220         &dev_attr_usbip_sockfd.attr,
 221         &dev_attr_usbip_status.attr,
 222         NULL,
 223 };
 224
 225 static struct bin_attribute *dev_bin_attrs[] = {
 226         &bin_attr_dev_desc,
 227         NULL,
 228 };
 229
 230 const struct attribute_group vudc_attr_group = {
 231         .attrs = dev_attrs,
 232         .bin_attrs = dev_bin_attrs,
 233 };