Staging: USB/IP: add client driver
This adds the USB IP client driver
Brian Merrell cleaned up a lot of this code and submitted it for
inclusion. Greg also did a lot of cleanup.
Signed-off-by: Brian G. Merrell <bgmerrell@novell.com>
Cc: Takahiro Hirofuchi <hirofuchi@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/staging/usbip/vhci_hcd.c b/drivers/staging/usbip/vhci_hcd.c
new file mode 100644
index 0000000..5b5a2e3
--- /dev/null
+++ b/drivers/staging/usbip/vhci_hcd.c
@@ -0,0 +1,1275 @@
+/*
+ * Copyright (C) 2003-2008 Takahiro Hirofuchi
+ *
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+ * USA.
+ */
+
+
+#include "usbip_common.h"
+#include "vhci.h"
+
+#define DRIVER_VERSION "1.0"
+#define DRIVER_AUTHOR "Takahiro Hirofuchi"
+#define DRIVER_DESC "Virtual Host Controller Interface Driver for USB/IP"
+#define DRIVER_LICENCE "GPL"
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE(DRIVER_LICENCE);
+
+
+
+/*
+ * TODO
+ * - update root hub emulation
+ * - move the emulation code to userland ?
+ * porting to other operating systems
+ * minimize kernel code
+ * - add suspend/resume code
+ * - clean up everything
+ */
+
+
+/* See usb gadget dummy hcd */
+
+
+static int vhci_hub_status(struct usb_hcd *hcd, char *buff);
+static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
+ u16 wIndex, char *buff, u16 wLength);
+static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
+ gfp_t mem_flags);
+static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status);
+static int vhci_start(struct usb_hcd *vhci_hcd);
+static void vhci_stop(struct usb_hcd *hcd);
+static int vhci_get_frame_number(struct usb_hcd *hcd);
+
+static const char driver_name[] = "vhci_hcd";
+static const char driver_desc[] = "USB/IP Virtual Host Contoroller";
+
+struct vhci_hcd *the_controller;
+
+static const char *bit_desc[] = {
+ "CONNECTION", /*0*/
+ "ENABLE", /*1*/
+ "SUSPEND", /*2*/
+ "OVER_CURRENT", /*3*/
+ "RESET", /*4*/
+ "R5", /*5*/
+ "R6", /*6*/
+ "R7", /*7*/
+ "POWER", /*8*/
+ "LOWSPEED", /*9*/
+ "HIGHSPEED", /*10*/
+ "PORT_TEST", /*11*/
+ "INDICATOR", /*12*/
+ "R13", /*13*/
+ "R14", /*14*/
+ "R15", /*15*/
+ "C_CONNECTION", /*16*/
+ "C_ENABLE", /*17*/
+ "C_SUSPEND", /*18*/
+ "C_OVER_CURRENT", /*19*/
+ "C_RESET", /*20*/
+ "R21", /*21*/
+ "R22", /*22*/
+ "R23", /*23*/
+ "R24", /*24*/
+ "R25", /*25*/
+ "R26", /*26*/
+ "R27", /*27*/
+ "R28", /*28*/
+ "R29", /*29*/
+ "R30", /*30*/
+ "R31", /*31*/
+};
+
+
+static void dump_port_status(u32 status)
+{
+ int i = 0;
+
+ printk(KERN_DEBUG "status %08x:", status);
+ for (i = 0; i < 32; i++) {
+ if (status & (1 << i))
+ printk(" %s", bit_desc[i]);
+ }
+
+ printk("\n");
+}
+
+
+
+void rh_port_connect(int rhport, enum usb_device_speed speed)
+{
+ unsigned long flags;
+
+ dbg_vhci_rh("rh_port_connect %d\n", rhport);
+
+ spin_lock_irqsave(&the_controller->lock, flags);
+
+ the_controller->port_status[rhport] |= USB_PORT_STAT_CONNECTION
+ | (1 << USB_PORT_FEAT_C_CONNECTION);
+
+ switch (speed) {
+ case USB_SPEED_HIGH:
+ the_controller->port_status[rhport] |= USB_PORT_STAT_HIGH_SPEED;
+ break;
+ case USB_SPEED_LOW:
+ the_controller->port_status[rhport] |= USB_PORT_STAT_LOW_SPEED;
+ break;
+ default:
+ break;
+ }
+
+ /* spin_lock(&the_controller->vdev[rhport].ud.lock);
+ * the_controller->vdev[rhport].ud.status = VDEV_CONNECT;
+ * spin_unlock(&the_controller->vdev[rhport].ud.lock); */
+
+ the_controller->pending_port = rhport;
+
+ spin_unlock_irqrestore(&the_controller->lock, flags);
+
+ usb_hcd_poll_rh_status(vhci_to_hcd(the_controller));
+}
+
+void rh_port_disconnect(int rhport)
+{
+ unsigned long flags;
+
+ dbg_vhci_rh("rh_port_disconnect %d\n", rhport);
+
+ spin_lock_irqsave(&the_controller->lock, flags);
+ /* stop_activity(dum, driver); */
+ the_controller->port_status[rhport] &= ~USB_PORT_STAT_CONNECTION;
+ the_controller->port_status[rhport] |=
+ (1 << USB_PORT_FEAT_C_CONNECTION);
+
+
+ /* not yet complete the disconnection
+ * spin_lock(&vdev->ud.lock);
+ * vdev->ud.status = VHC_ST_DISCONNECT;
+ * spin_unlock(&vdev->ud.lock); */
+
+ spin_unlock_irqrestore(&the_controller->lock, flags);
+}
+
+
+
+/*----------------------------------------------------------------------*/
+
+#define PORT_C_MASK \
+ ((USB_PORT_STAT_C_CONNECTION \
+ | USB_PORT_STAT_C_ENABLE \
+ | USB_PORT_STAT_C_SUSPEND \
+ | USB_PORT_STAT_C_OVERCURRENT \
+ | USB_PORT_STAT_C_RESET) << 16)
+
+/*
+ * This function is almostly the same as dummy_hcd.c:dummy_hub_status() without
+ * suspend/resume support. But, it is modified to provide multiple ports.
+ *
+ * @buf: a bitmap to show which port status has been changed.
+ * bit 0: reserved or used for another purpose?
+ * bit 1: the status of port 0 has been changed.
+ * bit 2: the status of port 1 has been changed.
+ * ...
+ * bit 7: the status of port 6 has been changed.
+ * bit 8: the status of port 7 has been changed.
+ * ...
+ * bit 15: the status of port 14 has been changed.
+ *
+ * So, the maximum number of ports is 31 ( port 0 to port 30) ?
+ *
+ * The return value is the actual transfered length in byte. If nothing has
+ * been changed, return 0. In the case that the number of ports is less than or
+ * equal to 6 (VHCI_NPORTS==7), return 1.
+ *
+ */
+static int vhci_hub_status(struct usb_hcd *hcd, char *buf)
+{
+ struct vhci_hcd *vhci;
+ unsigned long flags;
+ int retval = 0;
+
+ /* the enough buffer is allocated according to USB_MAXCHILDREN */
+ unsigned long *event_bits = (unsigned long *) buf;
+ int rhport;
+ int changed = 0;
+
+
+ *event_bits = 0;
+
+ vhci = hcd_to_vhci(hcd);
+
+ spin_lock_irqsave(&vhci->lock, flags);
+ if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)) {
+ dbg_vhci_rh("hw accessible flag in on?\n");
+ goto done;
+ }
+
+ /* check pseudo status register for each port */
+ for (rhport = 0; rhport < VHCI_NPORTS; rhport++) {
+ if ((vhci->port_status[rhport] & PORT_C_MASK)) {
+ /* The status of a port has been changed, */
+ dbg_vhci_rh("port %d is changed\n", rhport);
+
+ *event_bits |= 1 << (rhport + 1);
+ changed = 1;
+ }
+ }
+
+ uinfo("changed %d\n", changed);
+
+ if (hcd->state == HC_STATE_SUSPENDED)
+ usb_hcd_resume_root_hub(hcd);
+
+ if (changed)
+ retval = 1 + (VHCI_NPORTS / 8);
+ else
+ retval = 0;
+
+done:
+ spin_unlock_irqrestore(&vhci->lock, flags);
+ return retval;
+}
+
+/* See hub_configure in hub.c */
+static inline void hub_descriptor(struct usb_hub_descriptor *desc)
+{
+ memset(desc, 0, sizeof(*desc));
+ desc->bDescriptorType = 0x29;
+ desc->bDescLength = 9;
+ desc->wHubCharacteristics = (__force __u16)
+ (__constant_cpu_to_le16(0x0001));
+ desc->bNbrPorts = VHCI_NPORTS;
+ desc->bitmap[0] = 0xff;
+ desc->bitmap[1] = 0xff;
+}
+
+static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
+ u16 wIndex, char *buf, u16 wLength)
+{
+ struct vhci_hcd *dum;
+ int retval = 0;
+ unsigned long flags;
+ int rhport;
+
+ u32 prev_port_status[VHCI_NPORTS];
+
+ if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags))
+ return -ETIMEDOUT;
+
+ /*
+ * NOTE:
+ * wIndex shows the port number and begins from 1.
+ */
+ dbg_vhci_rh("typeReq %x wValue %x wIndex %x\n", typeReq, wValue,
+ wIndex);
+ if (wIndex > VHCI_NPORTS)
+ printk(KERN_ERR "%s: invalid port number %d\n", __func__, wIndex);
+ rhport = ((__u8)(wIndex & 0x00ff)) - 1;
+
+ dum = hcd_to_vhci(hcd);
+
+ spin_lock_irqsave(&dum->lock, flags);
+
+ /* store old status and compare now and old later */
+ if (dbg_flag_vhci_rh) {
+ int i = 0;
+ for (i = 0; i < VHCI_NPORTS; i++)
+ prev_port_status[i] = dum->port_status[i];
+ }
+
+ switch (typeReq) {
+ case ClearHubFeature:
+ dbg_vhci_rh(" ClearHubFeature\n");
+ break;
+ case ClearPortFeature:
+ switch (wValue) {
+ case USB_PORT_FEAT_SUSPEND:
+ if (dum->port_status[rhport] & USB_PORT_STAT_SUSPEND) {
+ /* 20msec signaling */
+ dum->resuming = 1;
+ dum->re_timeout =
+ jiffies + msecs_to_jiffies(20);
+ }
+ break;
+ case USB_PORT_FEAT_POWER:
+ dbg_vhci_rh(" ClearPortFeature: USB_PORT_FEAT_POWER\n");
+ dum->port_status[rhport] = 0;
+ /* dum->address = 0; */
+ /* dum->hdev = 0; */
+ dum->resuming = 0;
+ break;
+ case USB_PORT_FEAT_C_RESET:
+ dbg_vhci_rh(" ClearPortFeature: "
+ "USB_PORT_FEAT_C_RESET\n");
+ switch (dum->vdev[rhport].speed) {
+ case USB_SPEED_HIGH:
+ dum->port_status[rhport] |=
+ USB_PORT_STAT_HIGH_SPEED;
+ break;
+ case USB_SPEED_LOW:
+ dum->port_status[rhport] |=
+ USB_PORT_STAT_LOW_SPEED;
+ break;
+ default:
+ break;
+ }
+ default:
+ dbg_vhci_rh(" ClearPortFeature: default %x\n", wValue);
+ dum->port_status[rhport] &= ~(1 << wValue);
+ }
+ break;
+ case GetHubDescriptor:
+ dbg_vhci_rh(" GetHubDescriptor\n");
+ hub_descriptor((struct usb_hub_descriptor *) buf);
+ break;
+ case GetHubStatus:
+ dbg_vhci_rh(" GetHubStatus\n");
+ *(__le32 *) buf = __constant_cpu_to_le32(0);
+ break;
+ case GetPortStatus:
+ dbg_vhci_rh(" GetPortStatus port %x\n", wIndex);
+ if (wIndex > VHCI_NPORTS || wIndex < 1) {
+ printk(KERN_ERR "%s: invalid port number %d\n",
+ __func__, wIndex);
+ retval = -EPIPE;
+ }
+
+ /* we do no care of resume. */
+
+ /* whoever resets or resumes must GetPortStatus to
+ * complete it!!
+ * */
+ if (dum->resuming && time_after(jiffies, dum->re_timeout)) {
+ printk(KERN_ERR "%s: not yet\n", __func__);
+ dum->port_status[rhport] |=
+ (1 << USB_PORT_FEAT_C_SUSPEND);
+ dum->port_status[rhport] &=
+ ~(1 << USB_PORT_FEAT_SUSPEND);
+ dum->resuming = 0;
+ dum->re_timeout = 0;
+ /* if (dum->driver && dum->driver->resume) {
+ * spin_unlock (&dum->lock);
+ * dum->driver->resume (&dum->gadget);
+ * spin_lock (&dum->lock);
+ * } */
+ }
+
+ if ((dum->port_status[rhport] & (1 << USB_PORT_FEAT_RESET)) !=
+ 0 && time_after(jiffies, dum->re_timeout)) {
+ dum->port_status[rhport] |=
+ (1 << USB_PORT_FEAT_C_RESET);
+ dum->port_status[rhport] &=
+ ~(1 << USB_PORT_FEAT_RESET);
+ dum->re_timeout = 0;
+
+ if (dum->vdev[rhport].ud.status ==
+ VDEV_ST_NOTASSIGNED) {
+ dbg_vhci_rh(" enable rhport %d (status %u)\n",
+ rhport,
+ dum->vdev[rhport].ud.status);
+ dum->port_status[rhport] |=
+ USB_PORT_STAT_ENABLE;
+ }
+#if 0
+ if (dum->driver) {
+
+ dum->port_status[rhport] |=
+ USB_PORT_STAT_ENABLE;
+ /* give it the best speed we agree on */
+ dum->gadget.speed = dum->driver->speed;
+ dum->gadget.ep0->maxpacket = 64;
+ switch (dum->gadget.speed) {
+ case USB_SPEED_HIGH:
+ dum->port_status[rhport] |=
+ USB_PORT_STAT_HIGH_SPEED;
+ break;
+ case USB_SPEED_LOW:
+ dum->gadget.ep0->maxpacket = 8;
+ dum->port_status[rhport] |=
+ USB_PORT_STAT_LOW_SPEED;
+ break;
+ default:
+ dum->gadget.speed = USB_SPEED_FULL;
+ break;
+ }
+ }
+#endif
+
+ }
+ ((u16 *) buf)[0] = cpu_to_le16(dum->port_status[rhport]);
+ ((u16 *) buf)[1] =
+ cpu_to_le16(dum->port_status[rhport] >> 16);
+
+ dbg_vhci_rh(" GetPortStatus bye %x %x\n", ((u16 *)buf)[0],
+ ((u16 *)buf)[1]);
+ break;
+ case SetHubFeature:
+ dbg_vhci_rh(" SetHubFeature\n");
+ retval = -EPIPE;
+ break;
+ case SetPortFeature:
+ switch (wValue) {
+ case USB_PORT_FEAT_SUSPEND:
+ dbg_vhci_rh(" SetPortFeature: "
+ "USB_PORT_FEAT_SUSPEND\n");
+ printk(KERN_ERR "%s: not yet\n", __func__);
+#if 0
+ dum->port_status[rhport] |=
+ (1 << USB_PORT_FEAT_SUSPEND);
+ if (dum->driver->suspend) {
+ spin_unlock(&dum->lock);
+ dum->driver->suspend(&dum->gadget);
+ spin_lock(&dum->lock);
+ }
+#endif
+ break;
+ case USB_PORT_FEAT_RESET:
+ dbg_vhci_rh(" SetPortFeature: USB_PORT_FEAT_RESET\n");
+ /* if it's already running, disconnect first */
+ if (dum->port_status[rhport] & USB_PORT_STAT_ENABLE) {
+ dum->port_status[rhport] &=
+ ~(USB_PORT_STAT_ENABLE |
+ USB_PORT_STAT_LOW_SPEED |
+ USB_PORT_STAT_HIGH_SPEED);
+#if 0
+ if (dum->driver) {
+ dev_dbg(hardware, "disconnect\n");
+ stop_activity(dum, dum->driver);
+ }
+#endif
+
+ /* FIXME test that code path! */
+ }
+ /* 50msec reset signaling */
+ dum->re_timeout = jiffies + msecs_to_jiffies(50);
+
+ /* FALLTHROUGH */
+ default:
+ dbg_vhci_rh(" SetPortFeature: default %d\n", wValue);
+ dum->port_status[rhport] |= (1 << wValue);
+ }
+ break;
+
+ default:
+ printk(KERN_ERR "%s: default: no such request\n", __func__);
+ /* dev_dbg (hardware,
+ * "hub control req%04x v%04x i%04x l%d\n",
+ * typeReq, wValue, wIndex, wLength); */
+
+ /* "protocol stall" on error */
+ retval = -EPIPE;
+ }
+
+ if (dbg_flag_vhci_rh) {
+ printk(KERN_DEBUG "port %d\n", rhport);
+ dump_port_status(prev_port_status[rhport]);
+ dump_port_status(dum->port_status[rhport]);
+ }
+ dbg_vhci_rh(" bye\n");
+
+ spin_unlock_irqrestore(&dum->lock, flags);
+
+ return retval;
+}
+
+
+
+/*----------------------------------------------------------------------*/
+
+static struct vhci_device *get_vdev(struct usb_device *udev)
+{
+ int i;
+
+ if (!udev)
+ return NULL;
+
+ for (i = 0; i < VHCI_NPORTS; i++)
+ if (the_controller->vdev[i].udev == udev)
+ return port_to_vdev(i);
+
+ return NULL;
+}
+
+static void vhci_tx_urb(struct urb *urb)
+{
+ struct vhci_device *vdev = get_vdev(urb->dev);
+ struct vhci_priv *priv;
+ unsigned long flag;
+
+ if (!vdev) {
+ err("could not get virtual device");
+ /* BUG(); */
+ return;
+ }
+
+ spin_lock_irqsave(&vdev->priv_lock, flag);
+
+ priv = kzalloc(sizeof(struct vhci_priv), GFP_ATOMIC);
+ if (!priv) {
+ dev_err(&urb->dev->dev, "malloc vhci_priv\n");
+ spin_unlock_irqrestore(&vdev->priv_lock, flag);
+ usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
+ return;
+ }
+
+ priv->seqnum = atomic_inc_return(&the_controller->seqnum);
+ if (priv->seqnum == 0xffff)
+ uinfo("seqnum max\n");
+
+ priv->vdev = vdev;
+ priv->urb = urb;
+
+ urb->hcpriv = (void *) priv;
+
+
+ list_add_tail(&priv->list, &vdev->priv_tx);
+
+ wake_up(&vdev->waitq_tx);
+ spin_unlock_irqrestore(&vdev->priv_lock, flag);
+}
+
+static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
+ gfp_t mem_flags)
+{
+ struct device *dev = &urb->dev->dev;
+ int ret = 0;
+ unsigned long flags;
+
+ dbg_vhci_hc("enter, usb_hcd %p urb %p mem_flags %d\n",
+ hcd, urb, mem_flags);
+
+ /* patch to usb_sg_init() is in 2.5.60 */
+ BUG_ON(!urb->transfer_buffer && urb->transfer_buffer_length);
+
+ spin_lock_irqsave(&the_controller->lock, flags);
+
+ /* check HC is active or not */
+ if (!HC_IS_RUNNING(hcd->state)) {
+ dev_err(dev, "HC is not running\n");
+ spin_unlock_irqrestore(&the_controller->lock, flags);
+ return -ENODEV;
+ }
+
+ if (urb->status != -EINPROGRESS) {
+ dev_err(dev, "URB already unlinked!, status %d\n", urb->status);
+ spin_unlock_irqrestore(&the_controller->lock, flags);
+ return urb->status;
+ }
+
+ ret = usb_hcd_link_urb_to_ep(hcd, urb);
+ if (ret)
+ goto no_need_unlink;
+
+ /*
+ * The enumelation process is as follows;
+ *
+ * 1. Get_Descriptor request to DevAddrs(0) EndPoint(0)
+ * to get max packet length of default pipe
+ *
+ * 2. Set_Address request to DevAddr(0) EndPoint(0)
+ *
+ */
+
+ if (usb_pipedevice(urb->pipe) == 0) {
+ __u8 type = usb_pipetype(urb->pipe);
+ struct usb_ctrlrequest *ctrlreq =
+ (struct usb_ctrlrequest *) urb->setup_packet;
+ struct vhci_device *vdev =
+ port_to_vdev(the_controller->pending_port);
+
+ if (type != PIPE_CONTROL || !ctrlreq) {
+ dev_err(dev, "invalid request to devnum 0\n");
+ ret = EINVAL;
+ goto no_need_xmit;
+ }
+
+ switch (ctrlreq->bRequest) {
+ case USB_REQ_SET_ADDRESS:
+ /* set_address may come when a device is reset */
+ dev_info(dev, "SetAddress Request (%d) to port %d\n",
+ ctrlreq->wValue, vdev->rhport);
+
+ vdev->udev = urb->dev;
+
+ spin_lock(&vdev->ud.lock);
+ vdev->ud.status = VDEV_ST_USED;
+ spin_unlock(&vdev->ud.lock);
+
+ if (urb->status == -EINPROGRESS) {
+ /* This request is successfully completed. */
+ /* If not -EINPROGRESS, possibly unlinked. */
+ urb->status = 0;
+ }
+
+ goto no_need_xmit;
+
+ case USB_REQ_GET_DESCRIPTOR:
+ if (ctrlreq->wValue == (USB_DT_DEVICE << 8))
+ dbg_vhci_hc("Not yet?: "
+ "Get_Descriptor to device 0 "
+ "(get max pipe size)\n");
+
+ /* FIXME: reference count? (usb_get_dev()) */
+ vdev->udev = urb->dev;
+ goto out;
+
+ default:
+ /* NOT REACHED */
+ dev_err(dev, "invalid request to devnum 0 bRequest %u, "
+ "wValue %u\n", ctrlreq->bRequest,
+ ctrlreq->wValue);
+ ret = -EINVAL;
+ goto no_need_xmit;
+ }
+
+ }
+
+out:
+ vhci_tx_urb(urb);
+
+ spin_unlock_irqrestore(&the_controller->lock, flags);
+
+ return 0;
+
+no_need_xmit:
+ usb_hcd_unlink_urb_from_ep(hcd, urb);
+no_need_unlink:
+ spin_unlock_irqrestore(&the_controller->lock, flags);
+
+ usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status);
+
+ return 0;
+}
+
+/*
+ * vhci_rx gives back the urb after receiving the reply of the urb. If an
+ * unlink pdu is sent or not, vhci_rx receives a normal return pdu and gives
+ * back its urb. For the driver unlinking the urb, the content of the urb is
+ * not important, but the calling to its completion handler is important; the
+ * completion of unlinking is notified by the completion handler.
+ *
+ *
+ * CLIENT SIDE
+ *
+ * - When vhci_hcd receives RET_SUBMIT,
+ *
+ * - case 1a). the urb of the pdu is not unlinking.
+ * - normal case
+ * => just give back the urb
+ *
+ * - case 1b). the urb of the pdu is unlinking.
+ * - usbip.ko will return a reply of the unlinking request.
+ * => give back the urb now and go to case 2b).
+ *
+ * - When vhci_hcd receives RET_UNLINK,
+ *
+ * - case 2a). a submit request is still pending in vhci_hcd.
+ * - urb was really pending in usbip.ko and urb_unlink_urb() was
+ * completed there.
+ * => free a pending submit request
+ * => notify unlink completeness by giving back the urb
+ *
+ * - case 2b). a submit request is *not* pending in vhci_hcd.
+ * - urb was already given back to the core driver.
+ * => do not give back the urb
+ *
+ *
+ * SERVER SIDE
+ *
+ * - When usbip receives CMD_UNLINK,
+ *
+ * - case 3a). the urb of the unlink request is now in submission.
+ * => do usb_unlink_urb().
+ * => after the unlink is completed, send RET_UNLINK.
+ *
+ * - case 3b). the urb of the unlink request is not in submission.
+ * - may be already completed or never be received
+ * => send RET_UNLINK
+ *
+ */
+static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
+{
+ unsigned long flags;
+ struct vhci_priv *priv;
+ struct vhci_device *vdev;
+
+ uinfo("vhci_hcd: dequeue a urb %p\n", urb);
+
+
+ spin_lock_irqsave(&the_controller->lock, flags);
+
+ priv = urb->hcpriv;
+ if (!priv) {
+ /* URB was never linked! or will be soon given back by
+ * vhci_rx. */
+ spin_unlock_irqrestore(&the_controller->lock, flags);
+ return 0;
+ }
+
+ {
+ int ret = 0;
+ ret = usb_hcd_check_unlink_urb(hcd, urb, status);
+ if (ret) {
+ spin_unlock_irqrestore(&the_controller->lock, flags);
+ return 0;
+ }
+ }
+
+ /* send unlink request here? */
+ vdev = priv->vdev;
+
+ if (!vdev->ud.tcp_socket) {
+ /* tcp connection is closed */
+ unsigned long flags2;
+
+ spin_lock_irqsave(&vdev->priv_lock, flags2);
+
+ uinfo("vhci_hcd: device %p seems to be disconnected\n", vdev);
+ list_del(&priv->list);
+ kfree(priv);
+ urb->hcpriv = NULL;
+
+ spin_unlock_irqrestore(&vdev->priv_lock, flags2);
+
+ } else {
+ /* tcp connection is alive */
+ unsigned long flags2;
+ struct vhci_unlink *unlink;
+
+ spin_lock_irqsave(&vdev->priv_lock, flags2);
+
+ /* setup CMD_UNLINK pdu */
+ unlink = kzalloc(sizeof(struct vhci_unlink), GFP_ATOMIC);
+ if (!unlink) {
+ uerr("malloc vhci_unlink\n");
+ spin_unlock_irqrestore(&vdev->priv_lock, flags2);
+ spin_unlock_irqrestore(&the_controller->lock, flags);
+ usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
+ return -ENOMEM;
+ }
+
+ unlink->seqnum = atomic_inc_return(&the_controller->seqnum);
+ if (unlink->seqnum == 0xffff)
+ uinfo("seqnum max\n");
+
+ unlink->unlink_seqnum = priv->seqnum;
+
+ uinfo("vhci_hcd: device %p seems to be still connected\n",
+ vdev);
+
+ /* send cmd_unlink and try to cancel the pending URB in the
+ * peer */
+ list_add_tail(&unlink->list, &vdev->unlink_tx);
+ wake_up(&vdev->waitq_tx);
+
+ spin_unlock_irqrestore(&vdev->priv_lock, flags2);
+ }
+
+
+ /*
+ * If tcp connection is alive, we have sent CMD_UNLINK.
+ * vhci_rx will receive RET_UNLINK and give back the URB.
+ * Otherwise, we give back it here.
+ */
+ if (!vdev->ud.tcp_socket) {
+ /* tcp connection is closed */
+ uinfo("vhci_hcd: vhci_urb_dequeue() gives back urb %p\n", urb);
+
+ usb_hcd_unlink_urb_from_ep(hcd, urb);
+
+ spin_unlock_irqrestore(&the_controller->lock, flags);
+ usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
+ urb->status);
+ spin_lock_irqsave(&the_controller->lock, flags);
+ }
+
+ spin_unlock_irqrestore(&the_controller->lock, flags);
+
+ dbg_vhci_hc("leave\n");
+ return 0;
+}
+
+
+static void vhci_device_unlink_cleanup(struct vhci_device *vdev)
+{
+ struct vhci_unlink *unlink, *tmp;
+
+ spin_lock(&vdev->priv_lock);
+
+ list_for_each_entry_safe(unlink, tmp, &vdev->unlink_tx, list) {
+ list_del(&unlink->list);
+ kfree(unlink);
+ }
+
+ list_for_each_entry_safe(unlink, tmp, &vdev->unlink_rx, list) {
+ list_del(&unlink->list);
+ kfree(unlink);
+ }
+
+ spin_unlock(&vdev->priv_lock);
+}
+
+/*
+ * The important thing is that only one context begins cleanup.
+ * This is why error handling and cleanup become simple.
+ * We do not want to consider race condition as possible.
+ */
+static void vhci_shutdown_connection(struct usbip_device *ud)
+{
+ struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
+
+ /* need this? see stub_dev.c */
+ if (ud->tcp_socket) {
+ udbg("shutdown tcp_socket %p\n", ud->tcp_socket);
+ kernel_sock_shutdown(ud->tcp_socket, SHUT_RDWR);
+ }
+
+ usbip_stop_threads(&vdev->ud);
+ uinfo("stop threads\n");
+
+ /* active connection is closed */
+ if (vdev->ud.tcp_socket != NULL) {
+ sock_release(vdev->ud.tcp_socket);
+ vdev->ud.tcp_socket = NULL;
+ }
+ uinfo("release socket\n");
+
+ vhci_device_unlink_cleanup(vdev);
+
+ /*
+ * rh_port_disconnect() is a trigger of ...
+ * usb_disable_device():
+ * disable all the endpoints for a USB device.
+ * usb_disable_endpoint():
+ * disable endpoints. pending urbs are unlinked(dequeued).
+ *
+ * NOTE: After calling rh_port_disconnect(), the USB device drivers of a
+ * deteched device should release used urbs in a cleanup function(i.e.
+ * xxx_disconnect()). Therefore, vhci_hcd does not need to release
+ * pushed urbs and their private data in this function.
+ *
+ * NOTE: vhci_dequeue() must be considered carefully. When shutdowning
+ * a connection, vhci_shutdown_connection() expects vhci_dequeue()
+ * gives back pushed urbs and frees their private data by request of
+ * the cleanup function of a USB driver. When unlinking a urb with an
+ * active connection, vhci_dequeue() does not give back the urb which
+ * is actually given back by vhci_rx after receiving its return pdu.
+ *
+ */
+ rh_port_disconnect(vdev->rhport);
+
+ uinfo("disconnect device\n");
+}
+
+
+static void vhci_device_reset(struct usbip_device *ud)
+{
+ struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
+
+ spin_lock(&ud->lock);
+
+ vdev->speed = 0;
+ vdev->devid = 0;
+
+ ud->tcp_socket = NULL;
+
+ ud->status = VDEV_ST_NULL;
+
+ spin_unlock(&ud->lock);
+}
+
+static void vhci_device_unusable(struct usbip_device *ud)
+{
+ spin_lock(&ud->lock);
+
+ ud->status = VDEV_ST_ERROR;
+
+ spin_unlock(&ud->lock);
+}
+
+static void vhci_device_init(struct vhci_device *vdev)
+{
+ memset(vdev, 0, sizeof(*vdev));
+
+ usbip_task_init(&vdev->ud.tcp_rx, "vhci_rx", vhci_rx_loop);
+ usbip_task_init(&vdev->ud.tcp_tx, "vhci_tx", vhci_tx_loop);
+
+ vdev->ud.side = USBIP_VHCI;
+ vdev->ud.status = VDEV_ST_NULL;
+ /* vdev->ud.lock = SPIN_LOCK_UNLOCKED; */
+ spin_lock_init(&vdev->ud.lock);
+
+ INIT_LIST_HEAD(&vdev->priv_rx);
+ INIT_LIST_HEAD(&vdev->priv_tx);
+ INIT_LIST_HEAD(&vdev->unlink_tx);
+ INIT_LIST_HEAD(&vdev->unlink_rx);
+ /* vdev->priv_lock = SPIN_LOCK_UNLOCKED; */
+ spin_lock_init(&vdev->priv_lock);
+
+ init_waitqueue_head(&vdev->waitq_tx);
+
+ vdev->ud.eh_ops.shutdown = vhci_shutdown_connection;
+ vdev->ud.eh_ops.reset = vhci_device_reset;
+ vdev->ud.eh_ops.unusable = vhci_device_unusable;
+
+ usbip_start_eh(&vdev->ud);
+}
+
+
+/*----------------------------------------------------------------------*/
+
+static int vhci_start(struct usb_hcd *hcd)
+{
+ struct vhci_hcd *vhci = hcd_to_vhci(hcd);
+ int rhport;
+ int err = 0;
+
+ dbg_vhci_hc("enter vhci_start\n");
+
+
+ /* initialize private data of usb_hcd */
+
+ for (rhport = 0; rhport < VHCI_NPORTS; rhport++) {
+ struct vhci_device *vdev = &vhci->vdev[rhport];
+ vhci_device_init(vdev);
+ vdev->rhport = rhport;
+ }
+
+ atomic_set(&vhci->seqnum, 0);
+ spin_lock_init(&vhci->lock);
+
+
+
+ hcd->power_budget = 0; /* no limit */
+ hcd->state = HC_STATE_RUNNING;
+ hcd->uses_new_polling = 1;
+
+
+ /* vhci_hcd is now ready to be controlled through sysfs */
+ err = sysfs_create_group(&vhci_dev(vhci)->kobj, &dev_attr_group);
+ if (err) {
+ uerr("create sysfs files\n");
+ return err;
+ }
+
+ return 0;
+}
+
+static void vhci_stop(struct usb_hcd *hcd)
+{
+ struct vhci_hcd *vhci = hcd_to_vhci(hcd);
+ int rhport = 0;
+
+ dbg_vhci_hc("stop VHCI controller\n");
+
+
+ /* 1. remove the userland interface of vhci_hcd */
+ sysfs_remove_group(&vhci_dev(vhci)->kobj, &dev_attr_group);
+
+ /* 2. shutdown all the ports of vhci_hcd */
+ for (rhport = 0 ; rhport < VHCI_NPORTS; rhport++) {
+ struct vhci_device *vdev = &vhci->vdev[rhport];
+
+ usbip_event_add(&vdev->ud, VDEV_EVENT_REMOVED);
+ usbip_stop_eh(&vdev->ud);
+ }
+
+
+ uinfo("vhci_stop done\n");
+}
+
+/*----------------------------------------------------------------------*/
+
+static int vhci_get_frame_number(struct usb_hcd *hcd)
+{
+ uerr("Not yet implemented\n");
+ return 0;
+}
+
+
+#ifdef CONFIG_PM
+
+/* FIXME: suspend/resume */
+static int vhci_bus_suspend(struct usb_hcd *hcd)
+{
+ struct vhci_hcd *vhci = hcd_to_vhci(hcd);
+
+ dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
+
+ spin_lock_irq(&vhci->lock);
+ /* vhci->rh_state = DUMMY_RH_SUSPENDED;
+ * set_link_state(vhci); */
+ hcd->state = HC_STATE_SUSPENDED;
+ spin_unlock_irq(&vhci->lock);
+
+ return 0;
+}
+
+static int vhci_bus_resume(struct usb_hcd *hcd)
+{
+ struct vhci_hcd *vhci = hcd_to_vhci(hcd);
+ int rc = 0;
+
+ dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
+
+ spin_lock_irq(&vhci->lock);
+ if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)) {
+ rc = -ESHUTDOWN;
+ } else {
+ /* vhci->rh_state = DUMMY_RH_RUNNING;
+ * set_link_state(vhci);
+ * if (!list_empty(&vhci->urbp_list))
+ * mod_timer(&vhci->timer, jiffies); */
+ hcd->state = HC_STATE_RUNNING;
+ }
+ spin_unlock_irq(&vhci->lock);
+ return rc;
+
+ return 0;
+}
+
+#else
+
+#define vhci_bus_suspend NULL
+#define vhci_bus_resume NULL
+#endif
+
+
+
+static struct hc_driver vhci_hc_driver = {
+ .description = driver_name,
+ .product_desc = driver_desc,
+ .hcd_priv_size = sizeof(struct vhci_hcd),
+
+ .flags = HCD_USB2,
+
+ .start = vhci_start,
+ .stop = vhci_stop,
+
+ .urb_enqueue = vhci_urb_enqueue,
+ .urb_dequeue = vhci_urb_dequeue,
+
+ .get_frame_number = vhci_get_frame_number,
+
+ .hub_status_data = vhci_hub_status,
+ .hub_control = vhci_hub_control,
+ .bus_suspend = vhci_bus_suspend,
+ .bus_resume = vhci_bus_resume,
+};
+
+static int vhci_hcd_probe(struct platform_device *pdev)
+{
+ struct usb_hcd *hcd;
+ int ret;
+
+ uinfo("proving...\n");
+
+ dbg_vhci_hc("name %s id %d\n", pdev->name, pdev->id);
+
+ /* will be removed */
+ if (pdev->dev.dma_mask) {
+ dev_info(&pdev->dev, "vhci_hcd DMA not supported\n");
+ return -EINVAL;
+ }
+
+ /*
+ * Allocate and initialize hcd.
+ * Our private data is also allocated automatically.
+ */
+ hcd = usb_create_hcd(&vhci_hc_driver, &pdev->dev, pdev->dev.bus_id);
+ if (!hcd) {
+ uerr("create hcd failed\n");
+ return -ENOMEM;
+ }
+
+
+ /* this is private data for vhci_hcd */
+ the_controller = hcd_to_vhci(hcd);
+
+ /*
+ * Finish generic HCD structure initialization and register.
+ * Call the driver's reset() and start() routines.
+ */
+ ret = usb_add_hcd(hcd, 0, 0);
+ if (ret != 0) {
+ uerr("usb_add_hcd failed %d\n", ret);
+ usb_put_hcd(hcd);
+ the_controller = NULL;
+ return ret;
+ }
+
+
+ dbg_vhci_hc("bye\n");
+ return 0;
+}
+
+
+static int vhci_hcd_remove(struct platform_device *pdev)
+{
+ struct usb_hcd *hcd;
+
+ hcd = platform_get_drvdata(pdev);
+ if (!hcd)
+ return 0;
+
+ /*
+ * Disconnects the root hub,
+ * then reverses the effects of usb_add_hcd(),
+ * invoking the HCD's stop() methods.
+ */
+ usb_remove_hcd(hcd);
+ usb_put_hcd(hcd);
+ the_controller = NULL;
+
+
+ return 0;
+}
+
+
+
+#ifdef CONFIG_PM
+
+/* what should happen for USB/IP under suspend/resume? */
+static int vhci_hcd_suspend(struct platform_device *pdev, pm_message_t state)
+{
+ struct usb_hcd *hcd;
+ int rhport = 0;
+ int connected = 0;
+ int ret = 0;
+
+ dev_dbg(&pdev->dev, "%s\n", __func__);
+
+ hcd = platform_get_drvdata(pdev);
+
+ spin_lock(&the_controller->lock);
+
+ for (rhport = 0; rhport < VHCI_NPORTS; rhport++)
+ if (the_controller->port_status[rhport] &
+ USB_PORT_STAT_CONNECTION)
+ connected += 1;
+
+ spin_unlock(&the_controller->lock);
+
+ if (connected > 0) {
+ uinfo("We have %d active connection%s. Do not suspend.\n",
+ connected, (connected == 1 ? "" : "s"));
+ ret = -EBUSY;
+ } else {
+ uinfo("suspend vhci_hcd");
+ clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
+ }
+
+ return ret;
+}
+
+static int vhci_hcd_resume(struct platform_device *pdev)
+{
+ struct usb_hcd *hcd;
+
+ dev_dbg(&pdev->dev, "%s\n", __func__);
+
+ hcd = platform_get_drvdata(pdev);
+ set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
+ usb_hcd_poll_rh_status(hcd);
+
+ return 0;
+}
+
+#else
+
+#define vhci_hcd_suspend NULL
+#define vhci_hcd_resume NULL
+
+#endif
+
+
+static struct platform_driver vhci_driver = {
+ .probe = vhci_hcd_probe,
+ .remove = __devexit_p(vhci_hcd_remove),
+ .suspend = vhci_hcd_suspend,
+ .resume = vhci_hcd_resume,
+ .driver = {
+ .name = (char *) driver_name,
+ .owner = THIS_MODULE,
+ },
+};
+
+/*----------------------------------------------------------------------*/
+
+/*
+ * The VHCI 'device' is 'virtual'; not a real plug&play hardware.
+ * We need to add this virtual device as a platform device arbitrarily:
+ * 1. platform_device_register()
+ */
+static void the_pdev_release(struct device *dev)
+{
+ return;
+}
+
+static struct platform_device the_pdev = {
+ /* should be the same name as driver_name */
+ .name = (char *) driver_name,
+ .id = -1,
+ .dev = {
+ /* .driver = &vhci_driver, */
+ .release = the_pdev_release,
+ },
+};
+
+static int __init vhci_init(void)
+{
+ int ret;
+
+ dbg_vhci_hc("enter\n");
+ if (usb_disabled())
+ return -ENODEV;
+
+ printk(KERN_INFO KBUILD_MODNAME ": %s, %s\n", driver_name,
+ DRIVER_VERSION);
+
+ ret = platform_driver_register(&vhci_driver);
+ if (ret < 0)
+ goto err_driver_register;
+
+ ret = platform_device_register(&the_pdev);
+ if (ret < 0)
+ goto err_platform_device_register;
+
+ dbg_vhci_hc("bye\n");
+ return ret;
+
+ /* error occurred */
+err_platform_device_register:
+ platform_driver_unregister(&vhci_driver);
+
+err_driver_register:
+ dbg_vhci_hc("bye\n");
+ return ret;
+}
+module_init(vhci_init);
+
+static void __exit vhci_cleanup(void)
+{
+ dbg_vhci_hc("enter\n");
+
+ platform_device_unregister(&the_pdev);
+ platform_driver_unregister(&vhci_driver);
+
+ dbg_vhci_hc("bye\n");
+}
+module_exit(vhci_cleanup);