| /* |
| * (C) Copyright Linus Torvalds 1999 |
| * (C) Copyright Johannes Erdfelt 1999-2001 |
| * (C) Copyright Andreas Gal 1999 |
| * (C) Copyright Gregory P. Smith 1999 |
| * (C) Copyright Deti Fliegl 1999 |
| * (C) Copyright Randy Dunlap 2000 |
| * (C) Copyright David Brownell 2000-2002 |
| * |
| * This program 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 program 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., 675 Mass Ave, Cambridge, MA 02139, USA. |
| */ |
| |
| #include <linux/config.h> |
| #include <linux/module.h> |
| #include <linux/version.h> |
| #include <linux/kernel.h> |
| #include <linux/slab.h> |
| #include <linux/completion.h> |
| #include <linux/utsname.h> |
| #include <linux/mm.h> |
| #include <asm/io.h> |
| #include <asm/scatterlist.h> |
| #include <linux/device.h> |
| #include <linux/dma-mapping.h> |
| #include <linux/mutex.h> |
| #include <asm/irq.h> |
| #include <asm/byteorder.h> |
| |
| #include <linux/usb.h> |
| |
| #include "usb.h" |
| #include "hcd.h" |
| #include "hub.h" |
| |
| |
| // #define USB_BANDWIDTH_MESSAGES |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* |
| * USB Host Controller Driver framework |
| * |
| * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing |
| * HCD-specific behaviors/bugs. |
| * |
| * This does error checks, tracks devices and urbs, and delegates to a |
| * "hc_driver" only for code (and data) that really needs to know about |
| * hardware differences. That includes root hub registers, i/o queues, |
| * and so on ... but as little else as possible. |
| * |
| * Shared code includes most of the "root hub" code (these are emulated, |
| * though each HC's hardware works differently) and PCI glue, plus request |
| * tracking overhead. The HCD code should only block on spinlocks or on |
| * hardware handshaking; blocking on software events (such as other kernel |
| * threads releasing resources, or completing actions) is all generic. |
| * |
| * Happens the USB 2.0 spec says this would be invisible inside the "USBD", |
| * and includes mostly a "HCDI" (HCD Interface) along with some APIs used |
| * only by the hub driver ... and that neither should be seen or used by |
| * usb client device drivers. |
| * |
| * Contributors of ideas or unattributed patches include: David Brownell, |
| * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ... |
| * |
| * HISTORY: |
| * 2002-02-21 Pull in most of the usb_bus support from usb.c; some |
| * associated cleanup. "usb_hcd" still != "usb_bus". |
| * 2001-12-12 Initial patch version for Linux 2.5.1 kernel. |
| */ |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* host controllers we manage */ |
| LIST_HEAD (usb_bus_list); |
| EXPORT_SYMBOL_GPL (usb_bus_list); |
| |
| /* used when allocating bus numbers */ |
| #define USB_MAXBUS 64 |
| struct usb_busmap { |
| unsigned long busmap [USB_MAXBUS / (8*sizeof (unsigned long))]; |
| }; |
| static struct usb_busmap busmap; |
| |
| /* used when updating list of hcds */ |
| DEFINE_MUTEX(usb_bus_list_lock); /* exported only for usbfs */ |
| EXPORT_SYMBOL_GPL (usb_bus_list_lock); |
| |
| /* used for controlling access to virtual root hubs */ |
| static DEFINE_SPINLOCK(hcd_root_hub_lock); |
| |
| /* used when updating hcd data */ |
| static DEFINE_SPINLOCK(hcd_data_lock); |
| |
| /* wait queue for synchronous unlinks */ |
| DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue); |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* |
| * Sharable chunks of root hub code. |
| */ |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| #define KERNEL_REL ((LINUX_VERSION_CODE >> 16) & 0x0ff) |
| #define KERNEL_VER ((LINUX_VERSION_CODE >> 8) & 0x0ff) |
| |
| /* usb 2.0 root hub device descriptor */ |
| static const u8 usb2_rh_dev_descriptor [18] = { |
| 0x12, /* __u8 bLength; */ |
| 0x01, /* __u8 bDescriptorType; Device */ |
| 0x00, 0x02, /* __le16 bcdUSB; v2.0 */ |
| |
| 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ |
| 0x00, /* __u8 bDeviceSubClass; */ |
| 0x01, /* __u8 bDeviceProtocol; [ usb 2.0 single TT ]*/ |
| 0x40, /* __u8 bMaxPacketSize0; 64 Bytes */ |
| |
| 0x00, 0x00, /* __le16 idVendor; */ |
| 0x00, 0x00, /* __le16 idProduct; */ |
| KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ |
| |
| 0x03, /* __u8 iManufacturer; */ |
| 0x02, /* __u8 iProduct; */ |
| 0x01, /* __u8 iSerialNumber; */ |
| 0x01 /* __u8 bNumConfigurations; */ |
| }; |
| |
| /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */ |
| |
| /* usb 1.1 root hub device descriptor */ |
| static const u8 usb11_rh_dev_descriptor [18] = { |
| 0x12, /* __u8 bLength; */ |
| 0x01, /* __u8 bDescriptorType; Device */ |
| 0x10, 0x01, /* __le16 bcdUSB; v1.1 */ |
| |
| 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ |
| 0x00, /* __u8 bDeviceSubClass; */ |
| 0x00, /* __u8 bDeviceProtocol; [ low/full speeds only ] */ |
| 0x40, /* __u8 bMaxPacketSize0; 64 Bytes */ |
| |
| 0x00, 0x00, /* __le16 idVendor; */ |
| 0x00, 0x00, /* __le16 idProduct; */ |
| KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ |
| |
| 0x03, /* __u8 iManufacturer; */ |
| 0x02, /* __u8 iProduct; */ |
| 0x01, /* __u8 iSerialNumber; */ |
| 0x01 /* __u8 bNumConfigurations; */ |
| }; |
| |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* Configuration descriptors for our root hubs */ |
| |
| static const u8 fs_rh_config_descriptor [] = { |
| |
| /* one configuration */ |
| 0x09, /* __u8 bLength; */ |
| 0x02, /* __u8 bDescriptorType; Configuration */ |
| 0x19, 0x00, /* __le16 wTotalLength; */ |
| 0x01, /* __u8 bNumInterfaces; (1) */ |
| 0x01, /* __u8 bConfigurationValue; */ |
| 0x00, /* __u8 iConfiguration; */ |
| 0xc0, /* __u8 bmAttributes; |
| Bit 7: must be set, |
| 6: Self-powered, |
| 5: Remote wakeup, |
| 4..0: resvd */ |
| 0x00, /* __u8 MaxPower; */ |
| |
| /* USB 1.1: |
| * USB 2.0, single TT organization (mandatory): |
| * one interface, protocol 0 |
| * |
| * USB 2.0, multiple TT organization (optional): |
| * two interfaces, protocols 1 (like single TT) |
| * and 2 (multiple TT mode) ... config is |
| * sometimes settable |
| * NOT IMPLEMENTED |
| */ |
| |
| /* one interface */ |
| 0x09, /* __u8 if_bLength; */ |
| 0x04, /* __u8 if_bDescriptorType; Interface */ |
| 0x00, /* __u8 if_bInterfaceNumber; */ |
| 0x00, /* __u8 if_bAlternateSetting; */ |
| 0x01, /* __u8 if_bNumEndpoints; */ |
| 0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */ |
| 0x00, /* __u8 if_bInterfaceSubClass; */ |
| 0x00, /* __u8 if_bInterfaceProtocol; [usb1.1 or single tt] */ |
| 0x00, /* __u8 if_iInterface; */ |
| |
| /* one endpoint (status change endpoint) */ |
| 0x07, /* __u8 ep_bLength; */ |
| 0x05, /* __u8 ep_bDescriptorType; Endpoint */ |
| 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */ |
| 0x03, /* __u8 ep_bmAttributes; Interrupt */ |
| 0x02, 0x00, /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */ |
| 0xff /* __u8 ep_bInterval; (255ms -- usb 2.0 spec) */ |
| }; |
| |
| static const u8 hs_rh_config_descriptor [] = { |
| |
| /* one configuration */ |
| 0x09, /* __u8 bLength; */ |
| 0x02, /* __u8 bDescriptorType; Configuration */ |
| 0x19, 0x00, /* __le16 wTotalLength; */ |
| 0x01, /* __u8 bNumInterfaces; (1) */ |
| 0x01, /* __u8 bConfigurationValue; */ |
| 0x00, /* __u8 iConfiguration; */ |
| 0xc0, /* __u8 bmAttributes; |
| Bit 7: must be set, |
| 6: Self-powered, |
| 5: Remote wakeup, |
| 4..0: resvd */ |
| 0x00, /* __u8 MaxPower; */ |
| |
| /* USB 1.1: |
| * USB 2.0, single TT organization (mandatory): |
| * one interface, protocol 0 |
| * |
| * USB 2.0, multiple TT organization (optional): |
| * two interfaces, protocols 1 (like single TT) |
| * and 2 (multiple TT mode) ... config is |
| * sometimes settable |
| * NOT IMPLEMENTED |
| */ |
| |
| /* one interface */ |
| 0x09, /* __u8 if_bLength; */ |
| 0x04, /* __u8 if_bDescriptorType; Interface */ |
| 0x00, /* __u8 if_bInterfaceNumber; */ |
| 0x00, /* __u8 if_bAlternateSetting; */ |
| 0x01, /* __u8 if_bNumEndpoints; */ |
| 0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */ |
| 0x00, /* __u8 if_bInterfaceSubClass; */ |
| 0x00, /* __u8 if_bInterfaceProtocol; [usb1.1 or single tt] */ |
| 0x00, /* __u8 if_iInterface; */ |
| |
| /* one endpoint (status change endpoint) */ |
| 0x07, /* __u8 ep_bLength; */ |
| 0x05, /* __u8 ep_bDescriptorType; Endpoint */ |
| 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */ |
| 0x03, /* __u8 ep_bmAttributes; Interrupt */ |
| 0x02, 0x00, /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */ |
| 0x0c /* __u8 ep_bInterval; (256ms -- usb 2.0 spec) */ |
| }; |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* |
| * helper routine for returning string descriptors in UTF-16LE |
| * input can actually be ISO-8859-1; ASCII is its 7-bit subset |
| */ |
| static int ascii2utf (char *s, u8 *utf, int utfmax) |
| { |
| int retval; |
| |
| for (retval = 0; *s && utfmax > 1; utfmax -= 2, retval += 2) { |
| *utf++ = *s++; |
| *utf++ = 0; |
| } |
| if (utfmax > 0) { |
| *utf = *s; |
| ++retval; |
| } |
| return retval; |
| } |
| |
| /* |
| * rh_string - provides manufacturer, product and serial strings for root hub |
| * @id: the string ID number (1: serial number, 2: product, 3: vendor) |
| * @hcd: the host controller for this root hub |
| * @type: string describing our driver |
| * @data: return packet in UTF-16 LE |
| * @len: length of the return packet |
| * |
| * Produces either a manufacturer, product or serial number string for the |
| * virtual root hub device. |
| */ |
| static int rh_string ( |
| int id, |
| struct usb_hcd *hcd, |
| u8 *data, |
| int len |
| ) { |
| char buf [100]; |
| |
| // language ids |
| if (id == 0) { |
| buf[0] = 4; buf[1] = 3; /* 4 bytes string data */ |
| buf[2] = 0x09; buf[3] = 0x04; /* MSFT-speak for "en-us" */ |
| len = min (len, 4); |
| memcpy (data, buf, len); |
| return len; |
| |
| // serial number |
| } else if (id == 1) { |
| strlcpy (buf, hcd->self.bus_name, sizeof buf); |
| |
| // product description |
| } else if (id == 2) { |
| strlcpy (buf, hcd->product_desc, sizeof buf); |
| |
| // id 3 == vendor description |
| } else if (id == 3) { |
| snprintf (buf, sizeof buf, "%s %s %s", system_utsname.sysname, |
| system_utsname.release, hcd->driver->description); |
| |
| // unsupported IDs --> "protocol stall" |
| } else |
| return -EPIPE; |
| |
| switch (len) { /* All cases fall through */ |
| default: |
| len = 2 + ascii2utf (buf, data + 2, len - 2); |
| case 2: |
| data [1] = 3; /* type == string */ |
| case 1: |
| data [0] = 2 * (strlen (buf) + 1); |
| case 0: |
| ; /* Compiler wants a statement here */ |
| } |
| return len; |
| } |
| |
| |
| /* Root hub control transfers execute synchronously */ |
| static int rh_call_control (struct usb_hcd *hcd, struct urb *urb) |
| { |
| struct usb_ctrlrequest *cmd; |
| u16 typeReq, wValue, wIndex, wLength; |
| u8 *ubuf = urb->transfer_buffer; |
| u8 tbuf [sizeof (struct usb_hub_descriptor)]; |
| const u8 *bufp = tbuf; |
| int len = 0; |
| int patch_wakeup = 0; |
| unsigned long flags; |
| int status = 0; |
| int n; |
| |
| cmd = (struct usb_ctrlrequest *) urb->setup_packet; |
| typeReq = (cmd->bRequestType << 8) | cmd->bRequest; |
| wValue = le16_to_cpu (cmd->wValue); |
| wIndex = le16_to_cpu (cmd->wIndex); |
| wLength = le16_to_cpu (cmd->wLength); |
| |
| if (wLength > urb->transfer_buffer_length) |
| goto error; |
| |
| urb->actual_length = 0; |
| switch (typeReq) { |
| |
| /* DEVICE REQUESTS */ |
| |
| case DeviceRequest | USB_REQ_GET_STATUS: |
| tbuf [0] = (hcd->remote_wakeup << USB_DEVICE_REMOTE_WAKEUP) |
| | (1 << USB_DEVICE_SELF_POWERED); |
| tbuf [1] = 0; |
| len = 2; |
| break; |
| case DeviceOutRequest | USB_REQ_CLEAR_FEATURE: |
| if (wValue == USB_DEVICE_REMOTE_WAKEUP) |
| hcd->remote_wakeup = 0; |
| else |
| goto error; |
| break; |
| case DeviceOutRequest | USB_REQ_SET_FEATURE: |
| if (hcd->can_wakeup && wValue == USB_DEVICE_REMOTE_WAKEUP) |
| hcd->remote_wakeup = 1; |
| else |
| goto error; |
| break; |
| case DeviceRequest | USB_REQ_GET_CONFIGURATION: |
| tbuf [0] = 1; |
| len = 1; |
| /* FALLTHROUGH */ |
| case DeviceOutRequest | USB_REQ_SET_CONFIGURATION: |
| break; |
| case DeviceRequest | USB_REQ_GET_DESCRIPTOR: |
| switch (wValue & 0xff00) { |
| case USB_DT_DEVICE << 8: |
| if (hcd->driver->flags & HCD_USB2) |
| bufp = usb2_rh_dev_descriptor; |
| else if (hcd->driver->flags & HCD_USB11) |
| bufp = usb11_rh_dev_descriptor; |
| else |
| goto error; |
| len = 18; |
| break; |
| case USB_DT_CONFIG << 8: |
| if (hcd->driver->flags & HCD_USB2) { |
| bufp = hs_rh_config_descriptor; |
| len = sizeof hs_rh_config_descriptor; |
| } else { |
| bufp = fs_rh_config_descriptor; |
| len = sizeof fs_rh_config_descriptor; |
| } |
| if (hcd->can_wakeup) |
| patch_wakeup = 1; |
| break; |
| case USB_DT_STRING << 8: |
| n = rh_string (wValue & 0xff, hcd, ubuf, wLength); |
| if (n < 0) |
| goto error; |
| urb->actual_length = n; |
| break; |
| default: |
| goto error; |
| } |
| break; |
| case DeviceRequest | USB_REQ_GET_INTERFACE: |
| tbuf [0] = 0; |
| len = 1; |
| /* FALLTHROUGH */ |
| case DeviceOutRequest | USB_REQ_SET_INTERFACE: |
| break; |
| case DeviceOutRequest | USB_REQ_SET_ADDRESS: |
| // wValue == urb->dev->devaddr |
| dev_dbg (hcd->self.controller, "root hub device address %d\n", |
| wValue); |
| break; |
| |
| /* INTERFACE REQUESTS (no defined feature/status flags) */ |
| |
| /* ENDPOINT REQUESTS */ |
| |
| case EndpointRequest | USB_REQ_GET_STATUS: |
| // ENDPOINT_HALT flag |
| tbuf [0] = 0; |
| tbuf [1] = 0; |
| len = 2; |
| /* FALLTHROUGH */ |
| case EndpointOutRequest | USB_REQ_CLEAR_FEATURE: |
| case EndpointOutRequest | USB_REQ_SET_FEATURE: |
| dev_dbg (hcd->self.controller, "no endpoint features yet\n"); |
| break; |
| |
| /* CLASS REQUESTS (and errors) */ |
| |
| default: |
| /* non-generic request */ |
| switch (typeReq) { |
| case GetHubStatus: |
| case GetPortStatus: |
| len = 4; |
| break; |
| case GetHubDescriptor: |
| len = sizeof (struct usb_hub_descriptor); |
| break; |
| } |
| status = hcd->driver->hub_control (hcd, |
| typeReq, wValue, wIndex, |
| tbuf, wLength); |
| break; |
| error: |
| /* "protocol stall" on error */ |
| status = -EPIPE; |
| } |
| |
| if (status) { |
| len = 0; |
| if (status != -EPIPE) { |
| dev_dbg (hcd->self.controller, |
| "CTRL: TypeReq=0x%x val=0x%x " |
| "idx=0x%x len=%d ==> %d\n", |
| typeReq, wValue, wIndex, |
| wLength, status); |
| } |
| } |
| if (len) { |
| if (urb->transfer_buffer_length < len) |
| len = urb->transfer_buffer_length; |
| urb->actual_length = len; |
| // always USB_DIR_IN, toward host |
| memcpy (ubuf, bufp, len); |
| |
| /* report whether RH hardware supports remote wakeup */ |
| if (patch_wakeup && |
| len > offsetof (struct usb_config_descriptor, |
| bmAttributes)) |
| ((struct usb_config_descriptor *)ubuf)->bmAttributes |
| |= USB_CONFIG_ATT_WAKEUP; |
| } |
| |
| /* any errors get returned through the urb completion */ |
| local_irq_save (flags); |
| spin_lock (&urb->lock); |
| if (urb->status == -EINPROGRESS) |
| urb->status = status; |
| spin_unlock (&urb->lock); |
| usb_hcd_giveback_urb (hcd, urb, NULL); |
| local_irq_restore (flags); |
| return 0; |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* |
| * Root Hub interrupt transfers are polled using a timer if the |
| * driver requests it; otherwise the driver is responsible for |
| * calling usb_hcd_poll_rh_status() when an event occurs. |
| * |
| * Completions are called in_interrupt(), but they may or may not |
| * be in_irq(). |
| */ |
| void usb_hcd_poll_rh_status(struct usb_hcd *hcd) |
| { |
| struct urb *urb; |
| int length; |
| unsigned long flags; |
| char buffer[4]; /* Any root hubs with > 31 ports? */ |
| |
| if (!hcd->uses_new_polling && !hcd->status_urb) |
| return; |
| |
| length = hcd->driver->hub_status_data(hcd, buffer); |
| if (length > 0) { |
| |
| /* try to complete the status urb */ |
| local_irq_save (flags); |
| spin_lock(&hcd_root_hub_lock); |
| urb = hcd->status_urb; |
| if (urb) { |
| spin_lock(&urb->lock); |
| if (urb->status == -EINPROGRESS) { |
| hcd->poll_pending = 0; |
| hcd->status_urb = NULL; |
| urb->status = 0; |
| urb->hcpriv = NULL; |
| urb->actual_length = length; |
| memcpy(urb->transfer_buffer, buffer, length); |
| } else /* urb has been unlinked */ |
| length = 0; |
| spin_unlock(&urb->lock); |
| } else |
| length = 0; |
| spin_unlock(&hcd_root_hub_lock); |
| |
| /* local irqs are always blocked in completions */ |
| if (length > 0) |
| usb_hcd_giveback_urb (hcd, urb, NULL); |
| else |
| hcd->poll_pending = 1; |
| local_irq_restore (flags); |
| } |
| |
| /* The USB 2.0 spec says 256 ms. This is close enough and won't |
| * exceed that limit if HZ is 100. */ |
| if (hcd->uses_new_polling ? hcd->poll_rh : |
| (length == 0 && hcd->status_urb != NULL)) |
| mod_timer (&hcd->rh_timer, jiffies + msecs_to_jiffies(250)); |
| } |
| EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status); |
| |
| /* timer callback */ |
| static void rh_timer_func (unsigned long _hcd) |
| { |
| usb_hcd_poll_rh_status((struct usb_hcd *) _hcd); |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb) |
| { |
| int retval; |
| unsigned long flags; |
| int len = 1 + (urb->dev->maxchild / 8); |
| |
| spin_lock_irqsave (&hcd_root_hub_lock, flags); |
| if (urb->status != -EINPROGRESS) /* already unlinked */ |
| retval = urb->status; |
| else if (hcd->status_urb || urb->transfer_buffer_length < len) { |
| dev_dbg (hcd->self.controller, "not queuing rh status urb\n"); |
| retval = -EINVAL; |
| } else { |
| hcd->status_urb = urb; |
| urb->hcpriv = hcd; /* indicate it's queued */ |
| |
| if (!hcd->uses_new_polling) |
| mod_timer (&hcd->rh_timer, jiffies + |
| msecs_to_jiffies(250)); |
| |
| /* If a status change has already occurred, report it ASAP */ |
| else if (hcd->poll_pending) |
| mod_timer (&hcd->rh_timer, jiffies); |
| retval = 0; |
| } |
| spin_unlock_irqrestore (&hcd_root_hub_lock, flags); |
| return retval; |
| } |
| |
| static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb) |
| { |
| if (usb_pipeint (urb->pipe)) |
| return rh_queue_status (hcd, urb); |
| if (usb_pipecontrol (urb->pipe)) |
| return rh_call_control (hcd, urb); |
| return -EINVAL; |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* Asynchronous unlinks of root-hub control URBs are legal, but they |
| * don't do anything. Status URB unlinks must be made in process context |
| * with interrupts enabled. |
| */ |
| static int usb_rh_urb_dequeue (struct usb_hcd *hcd, struct urb *urb) |
| { |
| if (usb_pipeendpoint(urb->pipe) == 0) { /* Control URB */ |
| if (in_interrupt()) |
| return 0; /* nothing to do */ |
| |
| spin_lock_irq(&urb->lock); /* from usb_kill_urb */ |
| ++urb->reject; |
| spin_unlock_irq(&urb->lock); |
| |
| wait_event(usb_kill_urb_queue, |
| atomic_read(&urb->use_count) == 0); |
| |
| spin_lock_irq(&urb->lock); |
| --urb->reject; |
| spin_unlock_irq(&urb->lock); |
| |
| } else { /* Status URB */ |
| if (!hcd->uses_new_polling) |
| del_timer_sync (&hcd->rh_timer); |
| local_irq_disable (); |
| spin_lock (&hcd_root_hub_lock); |
| if (urb == hcd->status_urb) { |
| hcd->status_urb = NULL; |
| urb->hcpriv = NULL; |
| } else |
| urb = NULL; /* wasn't fully queued */ |
| spin_unlock (&hcd_root_hub_lock); |
| if (urb) |
| usb_hcd_giveback_urb (hcd, urb, NULL); |
| local_irq_enable (); |
| } |
| |
| return 0; |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* exported only within usbcore */ |
| struct usb_bus *usb_bus_get(struct usb_bus *bus) |
| { |
| if (bus) |
| kref_get(&bus->kref); |
| return bus; |
| } |
| |
| static void usb_host_release(struct kref *kref) |
| { |
| struct usb_bus *bus = container_of(kref, struct usb_bus, kref); |
| |
| if (bus->release) |
| bus->release(bus); |
| } |
| |
| /* exported only within usbcore */ |
| void usb_bus_put(struct usb_bus *bus) |
| { |
| if (bus) |
| kref_put(&bus->kref, usb_host_release); |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| static struct class *usb_host_class; |
| |
| int usb_host_init(void) |
| { |
| int retval = 0; |
| |
| usb_host_class = class_create(THIS_MODULE, "usb_host"); |
| if (IS_ERR(usb_host_class)) |
| retval = PTR_ERR(usb_host_class); |
| return retval; |
| } |
| |
| void usb_host_cleanup(void) |
| { |
| class_destroy(usb_host_class); |
| } |
| |
| /** |
| * usb_bus_init - shared initialization code |
| * @bus: the bus structure being initialized |
| * |
| * This code is used to initialize a usb_bus structure, memory for which is |
| * separately managed. |
| */ |
| static void usb_bus_init (struct usb_bus *bus) |
| { |
| memset (&bus->devmap, 0, sizeof(struct usb_devmap)); |
| |
| bus->devnum_next = 1; |
| |
| bus->root_hub = NULL; |
| bus->hcpriv = NULL; |
| bus->busnum = -1; |
| bus->bandwidth_allocated = 0; |
| bus->bandwidth_int_reqs = 0; |
| bus->bandwidth_isoc_reqs = 0; |
| |
| INIT_LIST_HEAD (&bus->bus_list); |
| |
| kref_init(&bus->kref); |
| } |
| |
| /** |
| * usb_alloc_bus - creates a new USB host controller structure |
| * @op: pointer to a struct usb_operations that this bus structure should use |
| * Context: !in_interrupt() |
| * |
| * Creates a USB host controller bus structure with the specified |
| * usb_operations and initializes all the necessary internal objects. |
| * |
| * If no memory is available, NULL is returned. |
| * |
| * The caller should call usb_put_bus() when it is finished with the structure. |
| */ |
| struct usb_bus *usb_alloc_bus (struct usb_operations *op) |
| { |
| struct usb_bus *bus; |
| |
| bus = kzalloc (sizeof *bus, GFP_KERNEL); |
| if (!bus) |
| return NULL; |
| usb_bus_init (bus); |
| bus->op = op; |
| return bus; |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /** |
| * usb_register_bus - registers the USB host controller with the usb core |
| * @bus: pointer to the bus to register |
| * Context: !in_interrupt() |
| * |
| * Assigns a bus number, and links the controller into usbcore data |
| * structures so that it can be seen by scanning the bus list. |
| */ |
| static int usb_register_bus(struct usb_bus *bus) |
| { |
| int busnum; |
| |
| mutex_lock(&usb_bus_list_lock); |
| busnum = find_next_zero_bit (busmap.busmap, USB_MAXBUS, 1); |
| if (busnum < USB_MAXBUS) { |
| set_bit (busnum, busmap.busmap); |
| bus->busnum = busnum; |
| } else { |
| printk (KERN_ERR "%s: too many buses\n", usbcore_name); |
| mutex_unlock(&usb_bus_list_lock); |
| return -E2BIG; |
| } |
| |
| bus->class_dev = class_device_create(usb_host_class, NULL, MKDEV(0,0), |
| bus->controller, "usb_host%d", busnum); |
| if (IS_ERR(bus->class_dev)) { |
| clear_bit(busnum, busmap.busmap); |
| mutex_unlock(&usb_bus_list_lock); |
| return PTR_ERR(bus->class_dev); |
| } |
| |
| class_set_devdata(bus->class_dev, bus); |
| |
| /* Add it to the local list of buses */ |
| list_add (&bus->bus_list, &usb_bus_list); |
| mutex_unlock(&usb_bus_list_lock); |
| |
| usb_notify_add_bus(bus); |
| |
| dev_info (bus->controller, "new USB bus registered, assigned bus number %d\n", bus->busnum); |
| return 0; |
| } |
| |
| /** |
| * usb_deregister_bus - deregisters the USB host controller |
| * @bus: pointer to the bus to deregister |
| * Context: !in_interrupt() |
| * |
| * Recycles the bus number, and unlinks the controller from usbcore data |
| * structures so that it won't be seen by scanning the bus list. |
| */ |
| static void usb_deregister_bus (struct usb_bus *bus) |
| { |
| dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum); |
| |
| /* |
| * NOTE: make sure that all the devices are removed by the |
| * controller code, as well as having it call this when cleaning |
| * itself up |
| */ |
| mutex_lock(&usb_bus_list_lock); |
| list_del (&bus->bus_list); |
| mutex_unlock(&usb_bus_list_lock); |
| |
| usb_notify_remove_bus(bus); |
| |
| clear_bit (bus->busnum, busmap.busmap); |
| |
| class_device_unregister(bus->class_dev); |
| } |
| |
| /** |
| * register_root_hub - called by usb_add_hcd() to register a root hub |
| * @hcd: host controller for this root hub |
| * |
| * This function registers the root hub with the USB subsystem. It sets up |
| * the device properly in the device tree and then calls usb_new_device() |
| * to register the usb device. It also assigns the root hub's USB address |
| * (always 1). |
| */ |
| static int register_root_hub(struct usb_hcd *hcd) |
| { |
| struct device *parent_dev = hcd->self.controller; |
| struct usb_device *usb_dev = hcd->self.root_hub; |
| const int devnum = 1; |
| int retval; |
| |
| usb_dev->devnum = devnum; |
| usb_dev->bus->devnum_next = devnum + 1; |
| memset (&usb_dev->bus->devmap.devicemap, 0, |
| sizeof usb_dev->bus->devmap.devicemap); |
| set_bit (devnum, usb_dev->bus->devmap.devicemap); |
| usb_set_device_state(usb_dev, USB_STATE_ADDRESS); |
| |
| mutex_lock(&usb_bus_list_lock); |
| |
| usb_dev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64); |
| retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE); |
| if (retval != sizeof usb_dev->descriptor) { |
| mutex_unlock(&usb_bus_list_lock); |
| dev_dbg (parent_dev, "can't read %s device descriptor %d\n", |
| usb_dev->dev.bus_id, retval); |
| return (retval < 0) ? retval : -EMSGSIZE; |
| } |
| |
| retval = usb_new_device (usb_dev); |
| if (retval) { |
| dev_err (parent_dev, "can't register root hub for %s, %d\n", |
| usb_dev->dev.bus_id, retval); |
| } |
| mutex_unlock(&usb_bus_list_lock); |
| |
| if (retval == 0) { |
| spin_lock_irq (&hcd_root_hub_lock); |
| hcd->rh_registered = 1; |
| spin_unlock_irq (&hcd_root_hub_lock); |
| |
| /* Did the HC die before the root hub was registered? */ |
| if (hcd->state == HC_STATE_HALT) |
| usb_hc_died (hcd); /* This time clean up */ |
| } |
| |
| return retval; |
| } |
| |
| void usb_enable_root_hub_irq (struct usb_bus *bus) |
| { |
| struct usb_hcd *hcd; |
| |
| hcd = container_of (bus, struct usb_hcd, self); |
| if (hcd->driver->hub_irq_enable && !hcd->poll_rh && |
| hcd->state != HC_STATE_HALT) |
| hcd->driver->hub_irq_enable (hcd); |
| } |
| |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /** |
| * usb_calc_bus_time - approximate periodic transaction time in nanoseconds |
| * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH} |
| * @is_input: true iff the transaction sends data to the host |
| * @isoc: true for isochronous transactions, false for interrupt ones |
| * @bytecount: how many bytes in the transaction. |
| * |
| * Returns approximate bus time in nanoseconds for a periodic transaction. |
| * See USB 2.0 spec section 5.11.3; only periodic transfers need to be |
| * scheduled in software, this function is only used for such scheduling. |
| */ |
| long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount) |
| { |
| unsigned long tmp; |
| |
| switch (speed) { |
| case USB_SPEED_LOW: /* INTR only */ |
| if (is_input) { |
| tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L; |
| return (64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp); |
| } else { |
| tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L; |
| return (64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp); |
| } |
| case USB_SPEED_FULL: /* ISOC or INTR */ |
| if (isoc) { |
| tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L; |
| return (((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp); |
| } else { |
| tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L; |
| return (9107L + BW_HOST_DELAY + tmp); |
| } |
| case USB_SPEED_HIGH: /* ISOC or INTR */ |
| // FIXME adjust for input vs output |
| if (isoc) |
| tmp = HS_NSECS_ISO (bytecount); |
| else |
| tmp = HS_NSECS (bytecount); |
| return tmp; |
| default: |
| pr_debug ("%s: bogus device speed!\n", usbcore_name); |
| return -1; |
| } |
| } |
| EXPORT_SYMBOL (usb_calc_bus_time); |
| |
| /* |
| * usb_check_bandwidth(): |
| * |
| * old_alloc is from host_controller->bandwidth_allocated in microseconds; |
| * bustime is from calc_bus_time(), but converted to microseconds. |
| * |
| * returns <bustime in us> if successful, |
| * or -ENOSPC if bandwidth request fails. |
| * |
| * FIXME: |
| * This initial implementation does not use Endpoint.bInterval |
| * in managing bandwidth allocation. |
| * It probably needs to be expanded to use Endpoint.bInterval. |
| * This can be done as a later enhancement (correction). |
| * |
| * This will also probably require some kind of |
| * frame allocation tracking...meaning, for example, |
| * that if multiple drivers request interrupts every 10 USB frames, |
| * they don't all have to be allocated at |
| * frame numbers N, N+10, N+20, etc. Some of them could be at |
| * N+11, N+21, N+31, etc., and others at |
| * N+12, N+22, N+32, etc. |
| * |
| * Similarly for isochronous transfers... |
| * |
| * Individual HCDs can schedule more directly ... this logic |
| * is not correct for high speed transfers. |
| */ |
| int usb_check_bandwidth (struct usb_device *dev, struct urb *urb) |
| { |
| unsigned int pipe = urb->pipe; |
| long bustime; |
| int is_in = usb_pipein (pipe); |
| int is_iso = usb_pipeisoc (pipe); |
| int old_alloc = dev->bus->bandwidth_allocated; |
| int new_alloc; |
| |
| |
| bustime = NS_TO_US (usb_calc_bus_time (dev->speed, is_in, is_iso, |
| usb_maxpacket (dev, pipe, !is_in))); |
| if (is_iso) |
| bustime /= urb->number_of_packets; |
| |
| new_alloc = old_alloc + (int) bustime; |
| if (new_alloc > FRAME_TIME_MAX_USECS_ALLOC) { |
| #ifdef DEBUG |
| char *mode = |
| #ifdef CONFIG_USB_BANDWIDTH |
| ""; |
| #else |
| "would have "; |
| #endif |
| dev_dbg (&dev->dev, "usb_check_bandwidth %sFAILED: %d + %ld = %d usec\n", |
| mode, old_alloc, bustime, new_alloc); |
| #endif |
| #ifdef CONFIG_USB_BANDWIDTH |
| bustime = -ENOSPC; /* report error */ |
| #endif |
| } |
| |
| return bustime; |
| } |
| EXPORT_SYMBOL (usb_check_bandwidth); |
| |
| |
| /** |
| * usb_claim_bandwidth - records bandwidth for a periodic transfer |
| * @dev: source/target of request |
| * @urb: request (urb->dev == dev) |
| * @bustime: bandwidth consumed, in (average) microseconds per frame |
| * @isoc: true iff the request is isochronous |
| * |
| * Bus bandwidth reservations are recorded purely for diagnostic purposes. |
| * HCDs are expected not to overcommit periodic bandwidth, and to record such |
| * reservations whenever endpoints are added to the periodic schedule. |
| * |
| * FIXME averaging per-frame is suboptimal. Better to sum over the HCD's |
| * entire periodic schedule ... 32 frames for OHCI, 1024 for UHCI, settable |
| * for EHCI (256/512/1024 frames, default 1024) and have the bus expose how |
| * large its periodic schedule is. |
| */ |
| void usb_claim_bandwidth (struct usb_device *dev, struct urb *urb, int bustime, int isoc) |
| { |
| dev->bus->bandwidth_allocated += bustime; |
| if (isoc) |
| dev->bus->bandwidth_isoc_reqs++; |
| else |
| dev->bus->bandwidth_int_reqs++; |
| urb->bandwidth = bustime; |
| |
| #ifdef USB_BANDWIDTH_MESSAGES |
| dev_dbg (&dev->dev, "bandwidth alloc increased by %d (%s) to %d for %d requesters\n", |
| bustime, |
| isoc ? "ISOC" : "INTR", |
| dev->bus->bandwidth_allocated, |
| dev->bus->bandwidth_int_reqs + dev->bus->bandwidth_isoc_reqs); |
| #endif |
| } |
| EXPORT_SYMBOL (usb_claim_bandwidth); |
| |
| |
| /** |
| * usb_release_bandwidth - reverses effect of usb_claim_bandwidth() |
| * @dev: source/target of request |
| * @urb: request (urb->dev == dev) |
| * @isoc: true iff the request is isochronous |
| * |
| * This records that previously allocated bandwidth has been released. |
| * Bandwidth is released when endpoints are removed from the host controller's |
| * periodic schedule. |
| */ |
| void usb_release_bandwidth (struct usb_device *dev, struct urb *urb, int isoc) |
| { |
| dev->bus->bandwidth_allocated -= urb->bandwidth; |
| if (isoc) |
| dev->bus->bandwidth_isoc_reqs--; |
| else |
| dev->bus->bandwidth_int_reqs--; |
| |
| #ifdef USB_BANDWIDTH_MESSAGES |
| dev_dbg (&dev->dev, "bandwidth alloc reduced by %d (%s) to %d for %d requesters\n", |
| urb->bandwidth, |
| isoc ? "ISOC" : "INTR", |
| dev->bus->bandwidth_allocated, |
| dev->bus->bandwidth_int_reqs + dev->bus->bandwidth_isoc_reqs); |
| #endif |
| urb->bandwidth = 0; |
| } |
| EXPORT_SYMBOL (usb_release_bandwidth); |
| |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* |
| * Generic HC operations. |
| */ |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| static void urb_unlink (struct urb *urb) |
| { |
| unsigned long flags; |
| |
| /* Release any periodic transfer bandwidth */ |
| if (urb->bandwidth) |
| usb_release_bandwidth (urb->dev, urb, |
| usb_pipeisoc (urb->pipe)); |
| |
| /* clear all state linking urb to this dev (and hcd) */ |
| |
| spin_lock_irqsave (&hcd_data_lock, flags); |
| list_del_init (&urb->urb_list); |
| spin_unlock_irqrestore (&hcd_data_lock, flags); |
| usb_put_dev (urb->dev); |
| } |
| |
| |
| /* may be called in any context with a valid urb->dev usecount |
| * caller surrenders "ownership" of urb |
| * expects usb_submit_urb() to have sanity checked and conditioned all |
| * inputs in the urb |
| */ |
| static int hcd_submit_urb (struct urb *urb, gfp_t mem_flags) |
| { |
| int status; |
| struct usb_hcd *hcd = urb->dev->bus->hcpriv; |
| struct usb_host_endpoint *ep; |
| unsigned long flags; |
| |
| if (!hcd) |
| return -ENODEV; |
| |
| usbmon_urb_submit(&hcd->self, urb); |
| |
| /* |
| * Atomically queue the urb, first to our records, then to the HCD. |
| * Access to urb->status is controlled by urb->lock ... changes on |
| * i/o completion (normal or fault) or unlinking. |
| */ |
| |
| // FIXME: verify that quiescing hc works right (RH cleans up) |
| |
| spin_lock_irqsave (&hcd_data_lock, flags); |
| ep = (usb_pipein(urb->pipe) ? urb->dev->ep_in : urb->dev->ep_out) |
| [usb_pipeendpoint(urb->pipe)]; |
| if (unlikely (!ep)) |
| status = -ENOENT; |
| else if (unlikely (urb->reject)) |
| status = -EPERM; |
| else switch (hcd->state) { |
| case HC_STATE_RUNNING: |
| case HC_STATE_RESUMING: |
| doit: |
| usb_get_dev (urb->dev); |
| list_add_tail (&urb->urb_list, &ep->urb_list); |
| status = 0; |
| break; |
| case HC_STATE_SUSPENDED: |
| /* HC upstream links (register access, wakeup signaling) can work |
| * even when the downstream links (and DMA etc) are quiesced; let |
| * usbcore talk to the root hub. |
| */ |
| if (hcd->self.controller->power.power_state.event == PM_EVENT_ON |
| && urb->dev->parent == NULL) |
| goto doit; |
| /* FALL THROUGH */ |
| default: |
| status = -ESHUTDOWN; |
| break; |
| } |
| spin_unlock_irqrestore (&hcd_data_lock, flags); |
| if (status) { |
| INIT_LIST_HEAD (&urb->urb_list); |
| usbmon_urb_submit_error(&hcd->self, urb, status); |
| return status; |
| } |
| |
| /* increment urb's reference count as part of giving it to the HCD |
| * (which now controls it). HCD guarantees that it either returns |
| * an error or calls giveback(), but not both. |
| */ |
| urb = usb_get_urb (urb); |
| atomic_inc (&urb->use_count); |
| |
| if (urb->dev == hcd->self.root_hub) { |
| /* NOTE: requirement on hub callers (usbfs and the hub |
| * driver, for now) that URBs' urb->transfer_buffer be |
| * valid and usb_buffer_{sync,unmap}() not be needed, since |
| * they could clobber root hub response data. |
| */ |
| status = rh_urb_enqueue (hcd, urb); |
| goto done; |
| } |
| |
| /* lower level hcd code should use *_dma exclusively, |
| * unless it uses pio or talks to another transport. |
| */ |
| if (hcd->self.controller->dma_mask) { |
| if (usb_pipecontrol (urb->pipe) |
| && !(urb->transfer_flags & URB_NO_SETUP_DMA_MAP)) |
| urb->setup_dma = dma_map_single ( |
| hcd->self.controller, |
| urb->setup_packet, |
| sizeof (struct usb_ctrlrequest), |
| DMA_TO_DEVICE); |
| if (urb->transfer_buffer_length != 0 |
| && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) |
| urb->transfer_dma = dma_map_single ( |
| hcd->self.controller, |
| urb->transfer_buffer, |
| urb->transfer_buffer_length, |
| usb_pipein (urb->pipe) |
| ? DMA_FROM_DEVICE |
| : DMA_TO_DEVICE); |
| } |
| |
| status = hcd->driver->urb_enqueue (hcd, ep, urb, mem_flags); |
| done: |
| if (unlikely (status)) { |
| urb_unlink (urb); |
| atomic_dec (&urb->use_count); |
| if (urb->reject) |
| wake_up (&usb_kill_urb_queue); |
| usb_put_urb (urb); |
| usbmon_urb_submit_error(&hcd->self, urb, status); |
| } |
| return status; |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* called in any context */ |
| static int hcd_get_frame_number (struct usb_device *udev) |
| { |
| struct usb_hcd *hcd = (struct usb_hcd *)udev->bus->hcpriv; |
| if (!HC_IS_RUNNING (hcd->state)) |
| return -ESHUTDOWN; |
| return hcd->driver->get_frame_number (hcd); |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* this makes the hcd giveback() the urb more quickly, by kicking it |
| * off hardware queues (which may take a while) and returning it as |
| * soon as practical. we've already set up the urb's return status, |
| * but we can't know if the callback completed already. |
| */ |
| static int |
| unlink1 (struct usb_hcd *hcd, struct urb *urb) |
| { |
| int value; |
| |
| if (urb->dev == hcd->self.root_hub) |
| value = usb_rh_urb_dequeue (hcd, urb); |
| else { |
| |
| /* The only reason an HCD might fail this call is if |
| * it has not yet fully queued the urb to begin with. |
| * Such failures should be harmless. */ |
| value = hcd->driver->urb_dequeue (hcd, urb); |
| } |
| |
| if (value != 0) |
| dev_dbg (hcd->self.controller, "dequeue %p --> %d\n", |
| urb, value); |
| return value; |
| } |
| |
| /* |
| * called in any context |
| * |
| * caller guarantees urb won't be recycled till both unlink() |
| * and the urb's completion function return |
| */ |
| static int hcd_unlink_urb (struct urb *urb, int status) |
| { |
| struct usb_host_endpoint *ep; |
| struct usb_hcd *hcd = NULL; |
| struct device *sys = NULL; |
| unsigned long flags; |
| struct list_head *tmp; |
| int retval; |
| |
| if (!urb) |
| return -EINVAL; |
| if (!urb->dev || !urb->dev->bus) |
| return -ENODEV; |
| ep = (usb_pipein(urb->pipe) ? urb->dev->ep_in : urb->dev->ep_out) |
| [usb_pipeendpoint(urb->pipe)]; |
| if (!ep) |
| return -ENODEV; |
| |
| /* |
| * we contend for urb->status with the hcd core, |
| * which changes it while returning the urb. |
| * |
| * Caller guaranteed that the urb pointer hasn't been freed, and |
| * that it was submitted. But as a rule it can't know whether or |
| * not it's already been unlinked ... so we respect the reversed |
| * lock sequence needed for the usb_hcd_giveback_urb() code paths |
| * (urb lock, then hcd_data_lock) in case some other CPU is now |
| * unlinking it. |
| */ |
| spin_lock_irqsave (&urb->lock, flags); |
| spin_lock (&hcd_data_lock); |
| |
| sys = &urb->dev->dev; |
| hcd = urb->dev->bus->hcpriv; |
| if (hcd == NULL) { |
| retval = -ENODEV; |
| goto done; |
| } |
| |
| /* insist the urb is still queued */ |
| list_for_each(tmp, &ep->urb_list) { |
| if (tmp == &urb->urb_list) |
| break; |
| } |
| if (tmp != &urb->urb_list) { |
| retval = -EIDRM; |
| goto done; |
| } |
| |
| /* Any status except -EINPROGRESS means something already started to |
| * unlink this URB from the hardware. So there's no more work to do. |
| */ |
| if (urb->status != -EINPROGRESS) { |
| retval = -EBUSY; |
| goto done; |
| } |
| |
| /* IRQ setup can easily be broken so that USB controllers |
| * never get completion IRQs ... maybe even the ones we need to |
| * finish unlinking the initial failed usb_set_address() |
| * or device descriptor fetch. |
| */ |
| if (!test_bit(HCD_FLAG_SAW_IRQ, &hcd->flags) |
| && hcd->self.root_hub != urb->dev) { |
| dev_warn (hcd->self.controller, "Unlink after no-IRQ? " |
| "Controller is probably using the wrong IRQ." |
| "\n"); |
| set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags); |
| } |
| |
| urb->status = status; |
| |
| spin_unlock (&hcd_data_lock); |
| spin_unlock_irqrestore (&urb->lock, flags); |
| |
| retval = unlink1 (hcd, urb); |
| if (retval == 0) |
| retval = -EINPROGRESS; |
| return retval; |
| |
| done: |
| spin_unlock (&hcd_data_lock); |
| spin_unlock_irqrestore (&urb->lock, flags); |
| if (retval != -EIDRM && sys && sys->driver) |
| dev_dbg (sys, "hcd_unlink_urb %p fail %d\n", urb, retval); |
| return retval; |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* disables the endpoint: cancels any pending urbs, then synchronizes with |
| * the hcd to make sure all endpoint state is gone from hardware. use for |
| * set_configuration, set_interface, driver removal, physical disconnect. |
| * |
| * example: a qh stored in ep->hcpriv, holding state related to endpoint |
| * type, maxpacket size, toggle, halt status, and scheduling. |
| */ |
| static void |
| hcd_endpoint_disable (struct usb_device *udev, struct usb_host_endpoint *ep) |
| { |
| struct usb_hcd *hcd; |
| struct urb *urb; |
| |
| hcd = udev->bus->hcpriv; |
| |
| WARN_ON (!HC_IS_RUNNING (hcd->state) && hcd->state != HC_STATE_HALT && |
| udev->state != USB_STATE_NOTATTACHED); |
| |
| local_irq_disable (); |
| |
| /* FIXME move most of this into message.c as part of its |
| * endpoint disable logic |
| */ |
| |
| /* ep is already gone from udev->ep_{in,out}[]; no more submits */ |
| rescan: |
| spin_lock (&hcd_data_lock); |
| list_for_each_entry (urb, &ep->urb_list, urb_list) { |
| int tmp; |
| |
| /* another cpu may be in hcd, spinning on hcd_data_lock |
| * to giveback() this urb. the races here should be |
| * small, but a full fix needs a new "can't submit" |
| * urb state. |
| * FIXME urb->reject should allow that... |
| */ |
| if (urb->status != -EINPROGRESS) |
| continue; |
| usb_get_urb (urb); |
| spin_unlock (&hcd_data_lock); |
| |
| spin_lock (&urb->lock); |
| tmp = urb->status; |
| if (tmp == -EINPROGRESS) |
| urb->status = -ESHUTDOWN; |
| spin_unlock (&urb->lock); |
| |
| /* kick hcd unless it's already returning this */ |
| if (tmp == -EINPROGRESS) { |
| tmp = urb->pipe; |
| unlink1 (hcd, urb); |
| dev_dbg (hcd->self.controller, |
| "shutdown urb %p pipe %08x ep%d%s%s\n", |
| urb, tmp, usb_pipeendpoint (tmp), |
| (tmp & USB_DIR_IN) ? "in" : "out", |
| ({ char *s; \ |
| switch (usb_pipetype (tmp)) { \ |
| case PIPE_CONTROL: s = ""; break; \ |
| case PIPE_BULK: s = "-bulk"; break; \ |
| case PIPE_INTERRUPT: s = "-intr"; break; \ |
| default: s = "-iso"; break; \ |
| }; s;})); |
| } |
| usb_put_urb (urb); |
| |
| /* list contents may have changed */ |
| goto rescan; |
| } |
| spin_unlock (&hcd_data_lock); |
| local_irq_enable (); |
| |
| /* synchronize with the hardware, so old configuration state |
| * clears out immediately (and will be freed). |
| */ |
| might_sleep (); |
| if (hcd->driver->endpoint_disable) |
| hcd->driver->endpoint_disable (hcd, ep); |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| #ifdef CONFIG_PM |
| |
| int hcd_bus_suspend (struct usb_bus *bus) |
| { |
| struct usb_hcd *hcd; |
| int status; |
| |
| hcd = container_of (bus, struct usb_hcd, self); |
| if (!hcd->driver->bus_suspend) |
| return -ENOENT; |
| hcd->state = HC_STATE_QUIESCING; |
| status = hcd->driver->bus_suspend (hcd); |
| if (status == 0) |
| hcd->state = HC_STATE_SUSPENDED; |
| else |
| dev_dbg(&bus->root_hub->dev, "%s fail, err %d\n", |
| "suspend", status); |
| return status; |
| } |
| |
| int hcd_bus_resume (struct usb_bus *bus) |
| { |
| struct usb_hcd *hcd; |
| int status; |
| |
| hcd = container_of (bus, struct usb_hcd, self); |
| if (!hcd->driver->bus_resume) |
| return -ENOENT; |
| if (hcd->state == HC_STATE_RUNNING) |
| return 0; |
| hcd->state = HC_STATE_RESUMING; |
| status = hcd->driver->bus_resume (hcd); |
| if (status == 0) |
| hcd->state = HC_STATE_RUNNING; |
| else { |
| dev_dbg(&bus->root_hub->dev, "%s fail, err %d\n", |
| "resume", status); |
| usb_hc_died(hcd); |
| } |
| return status; |
| } |
| |
| /* |
| * usb_hcd_suspend_root_hub - HCD autosuspends downstream ports |
| * @hcd: host controller for this root hub |
| * |
| * This call arranges that usb_hcd_resume_root_hub() is safe to call later; |
| * that the HCD's root hub polling is deactivated; and that the root's hub |
| * driver is suspended. HCDs may call this to autosuspend when their root |
| * hub's downstream ports are all inactive: unpowered, disconnected, |
| * disabled, or suspended. |
| * |
| * The HCD will autoresume on device connect change detection (using SRP |
| * or a D+/D- pullup). The HCD also autoresumes on remote wakeup signaling |
| * from any ports that are suspended (if that is enabled). In most cases, |
| * overcurrent signaling (on powered ports) will also start autoresume. |
| * |
| * Always called with IRQs blocked. |
| */ |
| void usb_hcd_suspend_root_hub (struct usb_hcd *hcd) |
| { |
| struct urb *urb; |
| |
| spin_lock (&hcd_root_hub_lock); |
| usb_suspend_root_hub (hcd->self.root_hub); |
| |
| /* force status urb to complete/unlink while suspended */ |
| if (hcd->status_urb) { |
| urb = hcd->status_urb; |
| urb->status = -ECONNRESET; |
| urb->hcpriv = NULL; |
| urb->actual_length = 0; |
| |
| del_timer (&hcd->rh_timer); |
| hcd->poll_pending = 0; |
| hcd->status_urb = NULL; |
| } else |
| urb = NULL; |
| spin_unlock (&hcd_root_hub_lock); |
| hcd->state = HC_STATE_SUSPENDED; |
| |
| if (urb) |
| usb_hcd_giveback_urb (hcd, urb, NULL); |
| } |
| EXPORT_SYMBOL_GPL(usb_hcd_suspend_root_hub); |
| |
| /** |
| * usb_hcd_resume_root_hub - called by HCD to resume its root hub |
| * @hcd: host controller for this root hub |
| * |
| * The USB host controller calls this function when its root hub is |
| * suspended (with the remote wakeup feature enabled) and a remote |
| * wakeup request is received. It queues a request for khubd to |
| * resume the root hub (that is, manage its downstream ports again). |
| */ |
| void usb_hcd_resume_root_hub (struct usb_hcd *hcd) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave (&hcd_root_hub_lock, flags); |
| if (hcd->rh_registered) |
| usb_resume_root_hub (hcd->self.root_hub); |
| spin_unlock_irqrestore (&hcd_root_hub_lock, flags); |
| } |
| EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub); |
| |
| #endif |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| #ifdef CONFIG_USB_OTG |
| |
| /** |
| * usb_bus_start_enum - start immediate enumeration (for OTG) |
| * @bus: the bus (must use hcd framework) |
| * @port_num: 1-based number of port; usually bus->otg_port |
| * Context: in_interrupt() |
| * |
| * Starts enumeration, with an immediate reset followed later by |
| * khubd identifying and possibly configuring the device. |
| * This is needed by OTG controller drivers, where it helps meet |
| * HNP protocol timing requirements for starting a port reset. |
| */ |
| int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num) |
| { |
| struct usb_hcd *hcd; |
| int status = -EOPNOTSUPP; |
| |
| /* NOTE: since HNP can't start by grabbing the bus's address0_sem, |
| * boards with root hubs hooked up to internal devices (instead of |
| * just the OTG port) may need more attention to resetting... |
| */ |
| hcd = container_of (bus, struct usb_hcd, self); |
| if (port_num && hcd->driver->start_port_reset) |
| status = hcd->driver->start_port_reset(hcd, port_num); |
| |
| /* run khubd shortly after (first) root port reset finishes; |
| * it may issue others, until at least 50 msecs have passed. |
| */ |
| if (status == 0) |
| mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10)); |
| return status; |
| } |
| EXPORT_SYMBOL (usb_bus_start_enum); |
| |
| #endif |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* |
| * usb_hcd_operations - adapts usb_bus framework to HCD framework (bus glue) |
| */ |
| static struct usb_operations usb_hcd_operations = { |
| .get_frame_number = hcd_get_frame_number, |
| .submit_urb = hcd_submit_urb, |
| .unlink_urb = hcd_unlink_urb, |
| .buffer_alloc = hcd_buffer_alloc, |
| .buffer_free = hcd_buffer_free, |
| .disable = hcd_endpoint_disable, |
| }; |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /** |
| * usb_hcd_giveback_urb - return URB from HCD to device driver |
| * @hcd: host controller returning the URB |
| * @urb: urb being returned to the USB device driver. |
| * @regs: pt_regs, passed down to the URB completion handler |
| * Context: in_interrupt() |
| * |
| * This hands the URB from HCD to its USB device driver, using its |
| * completion function. The HCD has freed all per-urb resources |
| * (and is done using urb->hcpriv). It also released all HCD locks; |
| * the device driver won't cause problems if it frees, modifies, |
| * or resubmits this URB. |
| */ |
| void usb_hcd_giveback_urb (struct usb_hcd *hcd, struct urb *urb, struct pt_regs *regs) |
| { |
| int at_root_hub; |
| |
| at_root_hub = (urb->dev == hcd->self.root_hub); |
| urb_unlink (urb); |
| |
| /* lower level hcd code should use *_dma exclusively */ |
| if (hcd->self.controller->dma_mask && !at_root_hub) { |
| if (usb_pipecontrol (urb->pipe) |
| && !(urb->transfer_flags & URB_NO_SETUP_DMA_MAP)) |
| dma_unmap_single (hcd->self.controller, urb->setup_dma, |
| sizeof (struct usb_ctrlrequest), |
| DMA_TO_DEVICE); |
| if (urb->transfer_buffer_length != 0 |
| && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) |
| dma_unmap_single (hcd->self.controller, |
| urb->transfer_dma, |
| urb->transfer_buffer_length, |
| usb_pipein (urb->pipe) |
| ? DMA_FROM_DEVICE |
| : DMA_TO_DEVICE); |
| } |
| |
| usbmon_urb_complete (&hcd->self, urb); |
| /* pass ownership to the completion handler */ |
| urb->complete (urb, regs); |
| atomic_dec (&urb->use_count); |
| if (unlikely (urb->reject)) |
| wake_up (&usb_kill_urb_queue); |
| usb_put_urb (urb); |
| } |
| EXPORT_SYMBOL (usb_hcd_giveback_urb); |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /** |
| * usb_hcd_irq - hook IRQs to HCD framework (bus glue) |
| * @irq: the IRQ being raised |
| * @__hcd: pointer to the HCD whose IRQ is being signaled |
| * @r: saved hardware registers |
| * |
| * If the controller isn't HALTed, calls the driver's irq handler. |
| * Checks whether the controller is now dead. |
| */ |
| irqreturn_t usb_hcd_irq (int irq, void *__hcd, struct pt_regs * r) |
| { |
| struct usb_hcd *hcd = __hcd; |
| int start = hcd->state; |
| |
| if (unlikely(start == HC_STATE_HALT || |
| !test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags))) |
| return IRQ_NONE; |
| if (hcd->driver->irq (hcd, r) == IRQ_NONE) |
| return IRQ_NONE; |
| |
| set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags); |
| |
| if (unlikely(hcd->state == HC_STATE_HALT)) |
| usb_hc_died (hcd); |
| return IRQ_HANDLED; |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /** |
| * usb_hc_died - report abnormal shutdown of a host controller (bus glue) |
| * @hcd: pointer to the HCD representing the controller |
| * |
| * This is called by bus glue to report a USB host controller that died |
| * while operations may still have been pending. It's called automatically |
| * by the PCI glue, so only glue for non-PCI busses should need to call it. |
| */ |
| void usb_hc_died (struct usb_hcd *hcd) |
| { |
| unsigned long flags; |
| |
| dev_err (hcd->self.controller, "HC died; cleaning up\n"); |
| |
| spin_lock_irqsave (&hcd_root_hub_lock, flags); |
| if (hcd->rh_registered) { |
| hcd->poll_rh = 0; |
| |
| /* make khubd clean up old urbs and devices */ |
| usb_set_device_state (hcd->self.root_hub, |
| USB_STATE_NOTATTACHED); |
| usb_kick_khubd (hcd->self.root_hub); |
| } |
| spin_unlock_irqrestore (&hcd_root_hub_lock, flags); |
| } |
| EXPORT_SYMBOL_GPL (usb_hc_died); |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| static void hcd_release (struct usb_bus *bus) |
| { |
| struct usb_hcd *hcd; |
| |
| hcd = container_of(bus, struct usb_hcd, self); |
| kfree(hcd); |
| } |
| |
| /** |
| * usb_create_hcd - create and initialize an HCD structure |
| * @driver: HC driver that will use this hcd |
| * @dev: device for this HC, stored in hcd->self.controller |
| * @bus_name: value to store in hcd->self.bus_name |
| * Context: !in_interrupt() |
| * |
| * Allocate a struct usb_hcd, with extra space at the end for the |
| * HC driver's private data. Initialize the generic members of the |
| * hcd structure. |
| * |
| * If memory is unavailable, returns NULL. |
| */ |
| struct usb_hcd *usb_create_hcd (const struct hc_driver *driver, |
| struct device *dev, char *bus_name) |
| { |
| struct usb_hcd *hcd; |
| |
| hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL); |
| if (!hcd) { |
| dev_dbg (dev, "hcd alloc failed\n"); |
| return NULL; |
| } |
| dev_set_drvdata(dev, hcd); |
| |
| usb_bus_init(&hcd->self); |
| hcd->self.op = &usb_hcd_operations; |
| hcd->self.hcpriv = hcd; |
| hcd->self.release = &hcd_release; |
| hcd->self.controller = dev; |
| hcd->self.bus_name = bus_name; |
| |
| init_timer(&hcd->rh_timer); |
| hcd->rh_timer.function = rh_timer_func; |
| hcd->rh_timer.data = (unsigned long) hcd; |
| |
| hcd->driver = driver; |
| hcd->product_desc = (driver->product_desc) ? driver->product_desc : |
| "USB Host Controller"; |
| |
| return hcd; |
| } |
| EXPORT_SYMBOL (usb_create_hcd); |
| |
| void usb_put_hcd (struct usb_hcd *hcd) |
| { |
| dev_set_drvdata(hcd->self.controller, NULL); |
| usb_bus_put(&hcd->self); |
| } |
| EXPORT_SYMBOL (usb_put_hcd); |
| |
| /** |
| * usb_add_hcd - finish generic HCD structure initialization and register |
| * @hcd: the usb_hcd structure to initialize |
| * @irqnum: Interrupt line to allocate |
| * @irqflags: Interrupt type flags |
| * |
| * Finish the remaining parts of generic HCD initialization: allocate the |
| * buffers of consistent memory, register the bus, request the IRQ line, |
| * and call the driver's reset() and start() routines. |
| */ |
| int usb_add_hcd(struct usb_hcd *hcd, |
| unsigned int irqnum, unsigned long irqflags) |
| { |
| int retval; |
| struct usb_device *rhdev; |
| |
| dev_info(hcd->self.controller, "%s\n", hcd->product_desc); |
| |
| set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags); |
| |
| /* HC is in reset state, but accessible. Now do the one-time init, |
| * bottom up so that hcds can customize the root hubs before khubd |
| * starts talking to them. (Note, bus id is assigned early too.) |
| */ |
| if ((retval = hcd_buffer_create(hcd)) != 0) { |
| dev_dbg(hcd->self.controller, "pool alloc failed\n"); |
| return retval; |
| } |
| |
| if ((retval = usb_register_bus(&hcd->self)) < 0) |
| goto err_register_bus; |
| |
| if ((rhdev = usb_alloc_dev(NULL, &hcd->self, 0)) == NULL) { |
| dev_err(hcd->self.controller, "unable to allocate root hub\n"); |
| retval = -ENOMEM; |
| goto err_allocate_root_hub; |
| } |
| rhdev->speed = (hcd->driver->flags & HCD_USB2) ? USB_SPEED_HIGH : |
| USB_SPEED_FULL; |
| hcd->self.root_hub = rhdev; |
| |
| /* "reset" is misnamed; its role is now one-time init. the controller |
| * should already have been reset (and boot firmware kicked off etc). |
| */ |
| if (hcd->driver->reset && (retval = hcd->driver->reset(hcd)) < 0) { |
| dev_err(hcd->self.controller, "can't setup\n"); |
| goto err_hcd_driver_setup; |
| } |
| |
| /* wakeup flag init is in transition; for now we can't rely on PCI to |
| * initialize these bits properly, so we let reset() override it. |
| * This init should _precede_ the reset() once PCI behaves. |
| */ |
| device_init_wakeup(&rhdev->dev, |
| device_can_wakeup(hcd->self.controller)); |
| |
| // ... all these hcd->*_wakeup flags will vanish |
| hcd->can_wakeup = device_can_wakeup(hcd->self.controller); |
| |
| /* hcd->driver->reset() reported can_wakeup, probably with |
| * assistance from board's boot firmware. |
| * NOTE: normal devices won't enable wakeup by default. |
| */ |
| if (hcd->can_wakeup) |
| dev_dbg(hcd->self.controller, "supports USB remote wakeup\n"); |
| hcd->remote_wakeup = hcd->can_wakeup; |
| |
| /* enable irqs just before we start the controller */ |
| if (hcd->driver->irq) { |
| char buf[8], *bufp = buf; |
| |
| #ifdef __sparc__ |
| bufp = __irq_itoa(irqnum); |
| #else |
| sprintf(buf, "%d", irqnum); |
| #endif |
| |
| snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d", |
| hcd->driver->description, hcd->self.busnum); |
| if ((retval = request_irq(irqnum, &usb_hcd_irq, irqflags, |
| hcd->irq_descr, hcd)) != 0) { |
| dev_err(hcd->self.controller, |
| "request interrupt %s failed\n", bufp); |
| goto err_request_irq; |
| } |
| hcd->irq = irqnum; |
| dev_info(hcd->self.controller, "irq %s, %s 0x%08llx\n", bufp, |
| (hcd->driver->flags & HCD_MEMORY) ? |
| "io mem" : "io base", |
| (unsigned long long)hcd->rsrc_start); |
| } else { |
| hcd->irq = -1; |
| if (hcd->rsrc_start) |
| dev_info(hcd->self.controller, "%s 0x%08llx\n", |
| (hcd->driver->flags & HCD_MEMORY) ? |
| "io mem" : "io base", |
| (unsigned long long)hcd->rsrc_start); |
| } |
| |
| if ((retval = hcd->driver->start(hcd)) < 0) { |
| dev_err(hcd->self.controller, "startup error %d\n", retval); |
| goto err_hcd_driver_start; |
| } |
| |
| /* starting here, usbcore will pay attention to this root hub */ |
| rhdev->bus_mA = min(500u, hcd->power_budget); |
| if ((retval = register_root_hub(hcd)) != 0) |
| goto err_register_root_hub; |
| |
| if (hcd->uses_new_polling && hcd->poll_rh) |
| usb_hcd_poll_rh_status(hcd); |
| return retval; |
| |
| err_register_root_hub: |
| hcd->driver->stop(hcd); |
| err_hcd_driver_start: |
| if (hcd->irq >= 0) |
| free_irq(irqnum, hcd); |
| err_request_irq: |
| err_hcd_driver_setup: |
| hcd->self.root_hub = NULL; |
| usb_put_dev(rhdev); |
| err_allocate_root_hub: |
| usb_deregister_bus(&hcd->self); |
| err_register_bus: |
| hcd_buffer_destroy(hcd); |
| return retval; |
| } |
| EXPORT_SYMBOL (usb_add_hcd); |
| |
| /** |
| * usb_remove_hcd - shutdown processing for generic HCDs |
| * @hcd: the usb_hcd structure to remove |
| * Context: !in_interrupt() |
| * |
| * Disconnects the root hub, then reverses the effects of usb_add_hcd(), |
| * invoking the HCD's stop() method. |
| */ |
| void usb_remove_hcd(struct usb_hcd *hcd) |
| { |
| dev_info(hcd->self.controller, "remove, state %x\n", hcd->state); |
| |
| if (HC_IS_RUNNING (hcd->state)) |
| hcd->state = HC_STATE_QUIESCING; |
| |
| dev_dbg(hcd->self.controller, "roothub graceful disconnect\n"); |
| spin_lock_irq (&hcd_root_hub_lock); |
| hcd->rh_registered = 0; |
| spin_unlock_irq (&hcd_root_hub_lock); |
| |
| mutex_lock(&usb_bus_list_lock); |
| usb_disconnect(&hcd->self.root_hub); |
| mutex_unlock(&usb_bus_list_lock); |
| |
| hcd->poll_rh = 0; |
| del_timer_sync(&hcd->rh_timer); |
| |
| hcd->driver->stop(hcd); |
| hcd->state = HC_STATE_HALT; |
| |
| if (hcd->irq >= 0) |
| free_irq(hcd->irq, hcd); |
| usb_deregister_bus(&hcd->self); |
| hcd_buffer_destroy(hcd); |
| } |
| EXPORT_SYMBOL (usb_remove_hcd); |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| #if defined(CONFIG_USB_MON) |
| |
| struct usb_mon_operations *mon_ops; |
| |
| /* |
| * The registration is unlocked. |
| * We do it this way because we do not want to lock in hot paths. |
| * |
| * Notice that the code is minimally error-proof. Because usbmon needs |
| * symbols from usbcore, usbcore gets referenced and cannot be unloaded first. |
| */ |
| |
| int usb_mon_register (struct usb_mon_operations *ops) |
| { |
| |
| if (mon_ops) |
| return -EBUSY; |
| |
| mon_ops = ops; |
| mb(); |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL (usb_mon_register); |
| |
| void usb_mon_deregister (void) |
| { |
| |
| if (mon_ops == NULL) { |
| printk(KERN_ERR "USB: monitor was not registered\n"); |
| return; |
| } |
| mon_ops = NULL; |
| mb(); |
| } |
| EXPORT_SYMBOL_GPL (usb_mon_deregister); |
| |
| #endif /* CONFIG_USB_MON */ |