// SPDX-License-Identifier: GPL-2.0+ /* * (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 */ #include <linux/bcd.h> #include <linux/module.h> #include <linux/version.h> #include <linux/kernel.h> #include <linux/sched/task_stack.h> #include <linux/slab.h> #include <linux/completion.h> #include <linux/utsname.h> #include <linux/mm.h> #include <asm/io.h> #include <linux/device.h> #include <linux/dma-mapping.h> #include <linux/mutex.h> #include <asm/irq.h> #include <asm/byteorder.h> #include <asm/unaligned.h> #include <linux/platform_device.h> #include <linux/workqueue.h> #include <linux/pm_runtime.h> #include <linux/types.h> #include <linux/phy/phy.h> #include <linux/usb.h> #include <linux/usb/hcd.h> #include <linux/usb/otg.h> #include "usb.h" #include "phy.h" /*-------------------------------------------------------------------------*/ /* * 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. */ /*-------------------------------------------------------------------------*/ /* Keep track of which host controller drivers are loaded */ unsigned long usb_hcds_loaded; EXPORT_SYMBOL_GPL(usb_hcds_loaded); /* host controllers we manage */ DEFINE_IDR (usb_bus_idr); EXPORT_SYMBOL_GPL (usb_bus_idr); /* used when allocating bus numbers */ #define USB_MAXBUS 64 /* used when updating list of hcds */ DEFINE_MUTEX(usb_bus_idr_lock); /* exported only for usbfs */ EXPORT_SYMBOL_GPL (usb_bus_idr_lock); /* used for controlling access to virtual root hubs */ static DEFINE_SPINLOCK(hcd_root_hub_lock); /* used when updating an endpoint's URB list */ static DEFINE_SPINLOCK(hcd_urb_list_lock); /* used to protect against unlinking URBs after the device is gone */ static DEFINE_SPINLOCK(hcd_urb_unlink_lock); /* wait queue for synchronous unlinks */ DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue); static inline int is_root_hub(struct usb_device *udev) { return (udev->parent == NULL); } /*-------------------------------------------------------------------------*/ /* * Sharable chunks of root hub code. */ /*-------------------------------------------------------------------------*/ #define KERNEL_REL bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff)) #define KERNEL_VER bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff)) /* usb 3.1 root hub device descriptor */ static const u8 usb31_rh_dev_descriptor[18] = { 0x12, /* __u8 bLength; */ USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 0x10, 0x03, /* __le16 bcdUSB; v3.1 */ 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 0x00, /* __u8 bDeviceSubClass; */ 0x03, /* __u8 bDeviceProtocol; USB 3 hub */ 0x09, /* __u8 bMaxPacketSize0; 2^9 = 512 Bytes */ 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 0x03, 0x00, /* __le16 idProduct; device 0x0003 */ KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 0x03, /* __u8 iManufacturer; */ 0x02, /* __u8 iProduct; */ 0x01, /* __u8 iSerialNumber; */ 0x01 /* __u8 bNumConfigurations; */ }; /* usb 3.0 root hub device descriptor */ static const u8 usb3_rh_dev_descriptor[18] = { 0x12, /* __u8 bLength; */ USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 0x00, 0x03, /* __le16 bcdUSB; v3.0 */ 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 0x00, /* __u8 bDeviceSubClass; */ 0x03, /* __u8 bDeviceProtocol; USB 3.0 hub */ 0x09, /* __u8 bMaxPacketSize0; 2^9 = 512 Bytes */ 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 0x03, 0x00, /* __le16 idProduct; device 0x0003 */ KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 0x03, /* __u8 iManufacturer; */ 0x02, /* __u8 iProduct; */ 0x01, /* __u8 iSerialNumber; */ 0x01 /* __u8 bNumConfigurations; */ }; /* usb 2.5 (wireless USB 1.0) root hub device descriptor */ static const u8 usb25_rh_dev_descriptor[18] = { 0x12, /* __u8 bLength; */ USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 0x50, 0x02, /* __le16 bcdUSB; v2.5 */ 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 0x00, /* __u8 bDeviceSubClass; */ 0x00, /* __u8 bDeviceProtocol; [ usb 2.0 no TT ] */ 0xFF, /* __u8 bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */ 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 0x02, 0x00, /* __le16 idProduct; device 0x0002 */ KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 0x03, /* __u8 iManufacturer; */ 0x02, /* __u8 iProduct; */ 0x01, /* __u8 iSerialNumber; */ 0x01 /* __u8 bNumConfigurations; */ }; /* usb 2.0 root hub device descriptor */ static const u8 usb2_rh_dev_descriptor[18] = { 0x12, /* __u8 bLength; */ USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 0x00, 0x02, /* __le16 bcdUSB; v2.0 */ 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 0x00, /* __u8 bDeviceSubClass; */ 0x00, /* __u8 bDeviceProtocol; [ usb 2.0 no TT ] */ 0x40, /* __u8 bMaxPacketSize0; 64 Bytes */ 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 0x02, 0x00, /* __le16 idProduct; device 0x0002 */ 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; */ USB_DT_DEVICE, /* __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 */ 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 0x01, 0x00, /* __le16 idProduct; device 0x0001 */ 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; */ USB_DT_CONFIG, /* __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; */ USB_DT_INTERFACE, /* __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; */ USB_DT_ENDPOINT, /* __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; */ USB_DT_CONFIG, /* __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; */ USB_DT_INTERFACE, /* __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; */ USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */ 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */ 0x03, /* __u8 ep_bmAttributes; Interrupt */ /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) * see hub.c:hub_configure() for details. */ (USB_MAXCHILDREN + 1 + 7) / 8, 0x00, 0x0c /* __u8 ep_bInterval; (256ms -- usb 2.0 spec) */ }; static const u8 ss_rh_config_descriptor[] = { /* one configuration */ 0x09, /* __u8 bLength; */ USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */ 0x1f, 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; */ /* one interface */ 0x09, /* __u8 if_bLength; */ USB_DT_INTERFACE, /* __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; */ 0x00, /* __u8 if_iInterface; */ /* one endpoint (status change endpoint) */ 0x07, /* __u8 ep_bLength; */ USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */ 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */ 0x03, /* __u8 ep_bmAttributes; Interrupt */ /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) * see hub.c:hub_configure() for details. */ (USB_MAXCHILDREN + 1 + 7) / 8, 0x00, 0x0c, /* __u8 ep_bInterval; (256ms -- usb 2.0 spec) */ /* one SuperSpeed endpoint companion descriptor */ 0x06, /* __u8 ss_bLength */ USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */ /* Companion */ 0x00, /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */ 0x00, /* __u8 ss_bmAttributes; 1 packet per service interval */ 0x02, 0x00 /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */ }; /* authorized_default behaviour: * -1 is authorized for all devices except wireless (old behaviour) * 0 is unauthorized for all devices * 1 is authorized for all devices * 2 is authorized for internal devices */ #define USB_AUTHORIZE_WIRED -1 #define USB_AUTHORIZE_NONE 0 #define USB_AUTHORIZE_ALL 1 #define USB_AUTHORIZE_INTERNAL 2 static int authorized_default = USB_AUTHORIZE_WIRED; module_param(authorized_default, int, S_IRUGO|S_IWUSR); MODULE_PARM_DESC(authorized_default, "Default USB device authorization: 0 is not authorized, 1 is " "authorized, 2 is authorized for internal devices, -1 is " "authorized except for wireless USB (default, old behaviour)"); /*-------------------------------------------------------------------------*/ /** * ascii2desc() - Helper routine for producing UTF-16LE string descriptors * @s: Null-terminated ASCII (actually ISO-8859-1) string * @buf: Buffer for USB string descriptor (header + UTF-16LE) * @len: Length (in bytes; may be odd) of descriptor buffer. * * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len, * whichever is less. * * Note: * USB String descriptors can contain at most 126 characters; input * strings longer than that are truncated. */ static unsigned ascii2desc(char const *s, u8 *buf, unsigned len) { unsigned n, t = 2 + 2*strlen(s); if (t > 254) t = 254; /* Longest possible UTF string descriptor */ if (len > t) len = t; t += USB_DT_STRING << 8; /* Now t is first 16 bits to store */ n = len; while (n--) { *buf++ = t; if (!n--) break; *buf++ = t >> 8; t = (unsigned char)*s++; } return len; } /** * rh_string() - provides string descriptors for root hub * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor) * @hcd: the host controller for this root hub * @data: buffer for output packet * @len: length of the provided buffer * * Produces either a manufacturer, product or serial number string for the * virtual root hub device. * * Return: The number of bytes filled in: the length of the descriptor or * of the provided buffer, whichever is less. */ static unsigned rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len) { char buf[100]; char const *s; static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04}; /* language ids */ switch (id) { case 0: /* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */ /* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */ if (len > 4) len = 4; memcpy(data, langids, len); return len; case 1: /* Serial number */ s = hcd->self.bus_name; break; case 2: /* Product name */ s = hcd->product_desc; break; case 3: /* Manufacturer */ snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname, init_utsname()->release, hcd->driver->description); s = buf; break; default: /* Can't happen; caller guarantees it */ return 0; } return ascii2desc(s, data, 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; unsigned len = 0; int status; u8 patch_wakeup = 0; u8 patch_protocol = 0; u16 tbuf_size; u8 *tbuf = NULL; const u8 *bufp; might_sleep(); spin_lock_irq(&hcd_root_hub_lock); status = usb_hcd_link_urb_to_ep(hcd, urb); spin_unlock_irq(&hcd_root_hub_lock); if (status) return status; urb->hcpriv = hcd; /* Indicate it's queued */ 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; /* * tbuf should be at least as big as the * USB hub descriptor. */ tbuf_size = max_t(u16, sizeof(struct usb_hub_descriptor), wLength); tbuf = kzalloc(tbuf_size, GFP_KERNEL); if (!tbuf) { status = -ENOMEM; goto err_alloc; } bufp = tbuf; urb->actual_length = 0; switch (typeReq) { /* DEVICE REQUESTS */ /* The root hub's remote wakeup enable bit is implemented using * driver model wakeup flags. If this system supports wakeup * through USB, userspace may change the default "allow wakeup" * policy through sysfs or these calls. * * Most root hubs support wakeup from downstream devices, for * runtime power management (disabling USB clocks and reducing * VBUS power usage). However, not all of them do so; silicon, * board, and BIOS bugs here are not uncommon, so these can't * be treated quite like external hubs. * * Likewise, not all root hubs will pass wakeup events upstream, * to wake up the whole system. So don't assume root hub and * controller capabilities are identical. */ case DeviceRequest | USB_REQ_GET_STATUS: tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev) << 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) device_set_wakeup_enable(&hcd->self.root_hub->dev, 0); else goto error; break; case DeviceOutRequest | USB_REQ_SET_FEATURE: if (device_can_wakeup(&hcd->self.root_hub->dev) && wValue == USB_DEVICE_REMOTE_WAKEUP) device_set_wakeup_enable(&hcd->self.root_hub->dev, 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: switch (hcd->speed) { case HCD_USB32: case HCD_USB31: bufp = usb31_rh_dev_descriptor; break; case HCD_USB3: bufp = usb3_rh_dev_descriptor; break; case HCD_USB25: bufp = usb25_rh_dev_descriptor; break; case HCD_USB2: bufp = usb2_rh_dev_descriptor; break; case HCD_USB11: bufp = usb11_rh_dev_descriptor; break; default: goto error; } len = 18; if (hcd->has_tt) patch_protocol = 1; break; case USB_DT_CONFIG << 8: switch (hcd->speed) { case HCD_USB32: case HCD_USB31: case HCD_USB3: bufp = ss_rh_config_descriptor; len = sizeof ss_rh_config_descriptor; break; case HCD_USB25: case HCD_USB2: bufp = hs_rh_config_descriptor; len = sizeof hs_rh_config_descriptor; break; case HCD_USB11: bufp = fs_rh_config_descriptor; len = sizeof fs_rh_config_descriptor; break; default: goto error; } if (device_can_wakeup(&hcd->self.root_hub->dev)) patch_wakeup = 1; break; case USB_DT_STRING << 8: if ((wValue & 0xff) < 4) urb->actual_length = rh_string(wValue & 0xff, hcd, ubuf, wLength); else /* unsupported IDs --> "protocol stall" */ goto error; break; case USB_DT_BOS << 8: goto nongeneric; 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: nongeneric: /* non-generic request */ switch (typeReq) { case GetHubStatus: len = 4; break; case GetPortStatus: if (wValue == HUB_PORT_STATUS) len = 4; else /* other port status types return 8 bytes */ len = 8; break; case GetHubDescriptor: len = sizeof (struct usb_hub_descriptor); break; case DeviceRequest | USB_REQ_GET_DESCRIPTOR: /* len is returned by hub_control */ break; } status = hcd->driver->hub_control (hcd, typeReq, wValue, wIndex, tbuf, wLength); if (typeReq == GetHubDescriptor) usb_hub_adjust_deviceremovable(hcd->self.root_hub, (struct usb_hub_descriptor *)tbuf); break; error: /* "protocol stall" on error */ status = -EPIPE; } if (status < 0) { 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); } } else if (status > 0) { /* hub_control may return the length of data copied. */ len = status; status = 0; } 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; /* report whether RH hardware has an integrated TT */ if (patch_protocol && len > offsetof(struct usb_device_descriptor, bDeviceProtocol)) ((struct usb_device_descriptor *) ubuf)-> bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT; } kfree(tbuf); err_alloc: /* any errors get returned through the urb completion */ spin_lock_irq(&hcd_root_hub_lock); usb_hcd_unlink_urb_from_ep(hcd, urb); usb_hcd_giveback_urb(hcd, urb, status); spin_unlock_irq(&hcd_root_hub_lock); 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[6]; /* Any root hubs with > 31 ports? */ if (unlikely(!hcd->rh_pollable)) return; 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 */ spin_lock_irqsave(&hcd_root_hub_lock, flags); urb = hcd->status_urb; if (urb) { clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags); hcd->status_urb = NULL; urb->actual_length = length; memcpy(urb->transfer_buffer, buffer, length); usb_hcd_unlink_urb_from_ep(hcd, urb); usb_hcd_giveback_urb(hcd, urb, 0); } else { length = 0; set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags); } spin_unlock_irqrestore(&hcd_root_hub_lock, flags); } /* The USB 2.0 spec says 256 ms. This is close enough and won't * exceed that limit if HZ is 100. The math is more clunky than * maybe expected, this is to make sure that all timers for USB devices * fire at the same time to give the CPU a break in between */ if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) : (length == 0 && hcd->status_urb != NULL)) mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4)); } EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status); /* timer callback */ static void rh_timer_func (struct timer_list *t) { struct usb_hcd *_hcd = from_timer(_hcd, t, rh_timer); usb_hcd_poll_rh_status(_hcd); } /*-------------------------------------------------------------------------*/ static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb) { int retval; unsigned long flags; unsigned len = 1 + (urb->dev->maxchild / 8); spin_lock_irqsave (&hcd_root_hub_lock, flags); if (hcd->status_urb || urb->transfer_buffer_length < len) { dev_dbg (hcd->self.controller, "not queuing rh status urb\n"); retval = -EINVAL; goto done; } retval = usb_hcd_link_urb_to_ep(hcd, urb); if (retval) goto done; hcd->status_urb = urb; urb->hcpriv = hcd; /* indicate it's queued */ if (!hcd->uses_new_polling) mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4)); /* If a status change has already occurred, report it ASAP */ else if (HCD_POLL_PENDING(hcd)) mod_timer(&hcd->rh_timer, jiffies); retval = 0; done: spin_unlock_irqrestore (&hcd_root_hub_lock, flags); return retval; } static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb) { if (usb_endpoint_xfer_int(&urb->ep->desc)) return rh_queue_status (hcd, urb); if (usb_endpoint_xfer_control(&urb->ep->desc)) return rh_call_control (hcd, urb); return -EINVAL; } /*-------------------------------------------------------------------------*/ /* Unlinks of root-hub control URBs are legal, but they don't do anything * since these URBs always execute synchronously. */ static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status) { unsigned long flags; int rc; spin_lock_irqsave(&hcd_root_hub_lock, flags); rc = usb_hcd_check_unlink_urb(hcd, urb, status); if (rc) goto done; if (usb_endpoint_num(&urb->ep->desc) == 0) { /* Control URB */ ; /* Do nothing */ } else { /* Status URB */ if (!hcd->uses_new_polling) del_timer (&hcd->rh_timer); if (urb == hcd->status_urb) { hcd->status_urb = NULL; usb_hcd_unlink_urb_from_ep(hcd, urb); usb_hcd_giveback_urb(hcd, urb, status); } } done: spin_unlock_irqrestore(&hcd_root_hub_lock, flags); return rc; } /* * Show & store the current value of authorized_default */ static ssize_t authorized_default_show(struct device *dev, struct device_attribute *attr, char *buf) { struct usb_device *rh_usb_dev = to_usb_device(dev); struct usb_bus *usb_bus = rh_usb_dev->bus; struct usb_hcd *hcd; hcd = bus_to_hcd(usb_bus); return snprintf(buf, PAGE_SIZE, "%u\n", hcd->dev_policy); } static ssize_t authorized_default_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { ssize_t result; unsigned val; struct usb_device *rh_usb_dev = to_usb_device(dev); struct usb_bus *usb_bus = rh_usb_dev->bus; struct usb_hcd *hcd; hcd = bus_to_hcd(usb_bus); result = sscanf(buf, "%u\n", &val); if (result == 1) { hcd->dev_policy = val <= USB_DEVICE_AUTHORIZE_INTERNAL ? val : USB_DEVICE_AUTHORIZE_ALL; result = size; } else { result = -EINVAL; } return result; } static DEVICE_ATTR_RW(authorized_default); /* * interface_authorized_default_show - show default authorization status * for USB interfaces * * note: interface_authorized_default is the default value * for initializing the authorized attribute of interfaces */ static ssize_t interface_authorized_default_show(struct device *dev, struct device_attribute *attr, char *buf) { struct usb_device *usb_dev = to_usb_device(dev); struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus); return sprintf(buf, "%u\n", !!HCD_INTF_AUTHORIZED(hcd)); } /* * interface_authorized_default_store - store default authorization status * for USB interfaces * * note: interface_authorized_default is the default value * for initializing the authorized attribute of interfaces */ static ssize_t interface_authorized_default_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct usb_device *usb_dev = to_usb_device(dev); struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus); int rc = count; bool val; if (strtobool(buf, &val) != 0) return -EINVAL; if (val) set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags); else clear_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags); return rc; } static DEVICE_ATTR_RW(interface_authorized_default); /* Group all the USB bus attributes */ static struct attribute *usb_bus_attrs[] = { &dev_attr_authorized_default.attr, &dev_attr_interface_authorized_default.attr, NULL, }; static const struct attribute_group usb_bus_attr_group = { .name = NULL, /* we want them in the same directory */ .attrs = usb_bus_attrs, }; /*-------------------------------------------------------------------------*/ /** * 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->busnum = -1; bus->bandwidth_allocated = 0; bus->bandwidth_int_reqs = 0; bus->bandwidth_isoc_reqs = 0; mutex_init(&bus->devnum_next_mutex); } /*-------------------------------------------------------------------------*/ /** * 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. * * Return: 0 if successful. A negative error code otherwise. */ static int usb_register_bus(struct usb_bus *bus) { int result = -E2BIG; int busnum; mutex_lock(&usb_bus_idr_lock); busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL); if (busnum < 0) { pr_err("%s: failed to get bus number\n", usbcore_name); goto error_find_busnum; } bus->busnum = busnum; mutex_unlock(&usb_bus_idr_lock); usb_notify_add_bus(bus); dev_info (bus->controller, "new USB bus registered, assigned bus " "number %d\n", bus->busnum); return 0; error_find_busnum: mutex_unlock(&usb_bus_idr_lock); return result; } /** * 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_idr_lock); idr_remove(&usb_bus_idr, bus->busnum); mutex_unlock(&usb_bus_idr_lock); usb_notify_remove_bus(bus); } /** * 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). * * Return: 0 if successful. A negative error code otherwise. */ 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; set_bit (devnum, usb_dev->bus->devmap.devicemap); usb_set_device_state(usb_dev, USB_STATE_ADDRESS); mutex_lock(&usb_bus_idr_lock); usb_dev->ep0.desc.wMaxPacketSize = 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_idr_lock); dev_dbg (parent_dev, "can't read %s device descriptor %d\n", dev_name(&usb_dev->dev), retval); return (retval < 0) ? retval : -EMSGSIZE; } if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) { retval = usb_get_bos_descriptor(usb_dev); if (!retval) { usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev); } else if (usb_dev->speed >= USB_SPEED_SUPER) { mutex_unlock(&usb_bus_idr_lock); dev_dbg(parent_dev, "can't read %s bos descriptor %d\n", dev_name(&usb_dev->dev), retval); return retval; } } retval = usb_new_device (usb_dev); if (retval) { dev_err (parent_dev, "can't register root hub for %s, %d\n", dev_name(&usb_dev->dev), retval); } else { 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_DEAD(hcd)) usb_hc_died (hcd); /* This time clean up */ } mutex_unlock(&usb_bus_idr_lock); return retval; } /* * usb_hcd_start_port_resume - a root-hub port is sending a resume signal * @bus: the bus which the root hub belongs to * @portnum: the port which is being resumed * * HCDs should call this function when they know that a resume signal is * being sent to a root-hub port. The root hub will be prevented from * going into autosuspend until usb_hcd_end_port_resume() is called. * * The bus's private lock must be held by the caller. */ void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum) { unsigned bit = 1 << portnum; if (!(bus->resuming_ports & bit)) { bus->resuming_ports |= bit; pm_runtime_get_noresume(&bus->root_hub->dev); } } EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume); /* * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal * @bus: the bus which the root hub belongs to * @portnum: the port which is being resumed * * HCDs should call this function when they know that a resume signal has * stopped being sent to a root-hub port. The root hub will be allowed to * autosuspend again. * * The bus's private lock must be held by the caller. */ void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum) { unsigned bit = 1 << portnum; if (bus->resuming_ports & bit) { bus->resuming_ports &= ~bit; pm_runtime_put_noidle(&bus->root_hub->dev); } } EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume); /*-------------------------------------------------------------------------*/ /** * 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. * * Return: Approximate bus time in nanoseconds for a periodic transaction. * * Note: * 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_GPL(usb_calc_bus_time); /*-------------------------------------------------------------------------*/ /* * Generic HC operations. */ /*-------------------------------------------------------------------------*/ /** * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue * @hcd: host controller to which @urb was submitted * @urb: URB being submitted * * Host controller drivers should call this routine in their enqueue() * method. The HCD's private spinlock must be held and interrupts must * be disabled. The actions carried out here are required for URB * submission, as well as for endpoint shutdown and for usb_kill_urb. * * Return: 0 for no error, otherwise a negative error code (in which case * the enqueue() method must fail). If no error occurs but enqueue() fails * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing * the private spinlock and returning. */ int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb) { int rc = 0; spin_lock(&hcd_urb_list_lock); /* Check that the URB isn't being killed */ if (unlikely(atomic_read(&urb->reject))) { rc = -EPERM; goto done; } if (unlikely(!urb->ep->enabled)) { rc = -ENOENT; goto done; } if (unlikely(!urb->dev->can_submit)) { rc = -EHOSTUNREACH; goto done; } /* * Check the host controller's state and add the URB to the * endpoint's queue. */ if (HCD_RH_RUNNING(hcd)) { urb->unlinked = 0; list_add_tail(&urb->urb_list, &urb->ep->urb_list); } else { rc = -ESHUTDOWN; goto done; } done: spin_unlock(&hcd_urb_list_lock); return rc; } EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep); /** * usb_hcd_check_unlink_urb - check whether an URB may be unlinked * @hcd: host controller to which @urb was submitted * @urb: URB being checked for unlinkability * @status: error code to store in @urb if the unlink succeeds * * Host controller drivers should call this routine in their dequeue() * method. The HCD's private spinlock must be held and interrupts must * be disabled. The actions carried out here are required for making * sure than an unlink is valid. * * Return: 0 for no error, otherwise a negative error code (in which case * the dequeue() method must fail). The possible error codes are: * * -EIDRM: @urb was not submitted or has already completed. * The completion function may not have been called yet. * * -EBUSY: @urb has already been unlinked. */ int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb, int status) { struct list_head *tmp; /* insist the urb is still queued */ list_for_each(tmp, &urb->ep->urb_list) { if (tmp == &urb->urb_list) break; } if (tmp != &urb->urb_list) return -EIDRM; /* 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->unlinked) return -EBUSY; urb->unlinked = status; return 0; } EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb); /** * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue * @hcd: host controller to which @urb was submitted * @urb: URB being unlinked * * Host controller drivers should call this routine before calling * usb_hcd_giveback_urb(). The HCD's private spinlock must be held and * interrupts must be disabled. The actions carried out here are required * for URB completion. */ void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb) { /* clear all state linking urb to this dev (and hcd) */ spin_lock(&hcd_urb_list_lock); list_del_init(&urb->urb_list); spin_unlock(&hcd_urb_list_lock); } EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep); /* * Some usb host controllers can only perform dma using a small SRAM area. * The usb core itself is however optimized for host controllers that can dma * using regular system memory - like pci devices doing bus mastering. * * To support host controllers with limited dma capabilities we provide dma * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag. * For this to work properly the host controller code must first use the * function dma_declare_coherent_memory() to point out which memory area * that should be used for dma allocations. * * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for * dma using dma_alloc_coherent() which in turn allocates from the memory * area pointed out with dma_declare_coherent_memory(). * * So, to summarize... * * - We need "local" memory, canonical example being * a small SRAM on a discrete controller being the * only memory that the controller can read ... * (a) "normal" kernel memory is no good, and * (b) there's not enough to share * * - The only *portable* hook for such stuff in the * DMA framework is dma_declare_coherent_memory() * * - So we use that, even though the primary requirement * is that the memory be "local" (hence addressable * by that device), not "coherent". * */ static int hcd_alloc_coherent(struct usb_bus *bus, gfp_t mem_flags, dma_addr_t *dma_handle, void **vaddr_handle, size_t size, enum dma_data_direction dir) { unsigned char *vaddr; if (*vaddr_handle == NULL) { WARN_ON_ONCE(1); return -EFAULT; } vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr), mem_flags, dma_handle); if (!vaddr) return -ENOMEM; /* * Store the virtual address of the buffer at the end * of the allocated dma buffer. The size of the buffer * may be uneven so use unaligned functions instead * of just rounding up. It makes sense to optimize for * memory footprint over access speed since the amount * of memory available for dma may be limited. */ put_unaligned((unsigned long)*vaddr_handle, (unsigned long *)(vaddr + size)); if (dir == DMA_TO_DEVICE) memcpy(vaddr, *vaddr_handle, size); *vaddr_handle = vaddr; return 0; } static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle, void **vaddr_handle, size_t size, enum dma_data_direction dir) { unsigned char *vaddr = *vaddr_handle; vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size)); if (dir == DMA_FROM_DEVICE) memcpy(vaddr, *vaddr_handle, size); hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle); *vaddr_handle = vaddr; *dma_handle = 0; } void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb) { if (IS_ENABLED(CONFIG_HAS_DMA) && (urb->transfer_flags & URB_SETUP_MAP_SINGLE)) dma_unmap_single(hcd->self.sysdev, urb->setup_dma, sizeof(struct usb_ctrlrequest), DMA_TO_DEVICE); else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL) hcd_free_coherent(urb->dev->bus, &urb->setup_dma, (void **) &urb->setup_packet, sizeof(struct usb_ctrlrequest), DMA_TO_DEVICE); /* Make it safe to call this routine more than once */ urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL); } EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma); static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb) { if (hcd->driver->unmap_urb_for_dma) hcd->driver->unmap_urb_for_dma(hcd, urb); else usb_hcd_unmap_urb_for_dma(hcd, urb); } void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb) { enum dma_data_direction dir; usb_hcd_unmap_urb_setup_for_dma(hcd, urb); dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE; if (IS_ENABLED(CONFIG_HAS_DMA) && (urb->transfer_flags & URB_DMA_MAP_SG)) dma_unmap_sg(hcd->self.sysdev, urb->sg, urb->num_sgs, dir); else if (IS_ENABLED(CONFIG_HAS_DMA) && (urb->transfer_flags & URB_DMA_MAP_PAGE)) dma_unmap_page(hcd->self.sysdev, urb->transfer_dma, urb->transfer_buffer_length, dir); else if (IS_ENABLED(CONFIG_HAS_DMA) && (urb->transfer_flags & URB_DMA_MAP_SINGLE)) dma_unmap_single(hcd->self.sysdev, urb->transfer_dma, urb->transfer_buffer_length, dir); else if (urb->transfer_flags & URB_MAP_LOCAL) hcd_free_coherent(urb->dev->bus, &urb->transfer_dma, &urb->transfer_buffer, urb->transfer_buffer_length, dir); /* Make it safe to call this routine more than once */ urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE | URB_DMA_MAP_SINGLE | URB_MAP_LOCAL); } EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma); static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flags) { if (hcd->driver->map_urb_for_dma) return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags); else return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags); } int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flags) { enum dma_data_direction dir; int ret = 0; /* Map the URB's buffers for DMA access. * Lower level HCD code should use *_dma exclusively, * unless it uses pio or talks to another transport, * or uses the provided scatter gather list for bulk. */ if (usb_endpoint_xfer_control(&urb->ep->desc)) { if (hcd->self.uses_pio_for_control) return ret; if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) { if (is_vmalloc_addr(urb->setup_packet)) { WARN_ONCE(1, "setup packet is not dma capable\n"); return -EAGAIN; } else if (object_is_on_stack(urb->setup_packet)) { WARN_ONCE(1, "setup packet is on stack\n"); return -EAGAIN; } urb->setup_dma = dma_map_single( hcd->self.sysdev, urb->setup_packet, sizeof(struct usb_ctrlrequest), DMA_TO_DEVICE); if (dma_mapping_error(hcd->self.sysdev, urb->setup_dma)) return -EAGAIN; urb->transfer_flags |= URB_SETUP_MAP_SINGLE; } else if (hcd->driver->flags & HCD_LOCAL_MEM) { ret = hcd_alloc_coherent( urb->dev->bus, mem_flags, &urb->setup_dma, (void **)&urb->setup_packet, sizeof(struct usb_ctrlrequest), DMA_TO_DEVICE); if (ret) return ret; urb->transfer_flags |= URB_SETUP_MAP_LOCAL; } } dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE; if (urb->transfer_buffer_length != 0 && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) { if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) { if (urb->num_sgs) { int n; /* We don't support sg for isoc transfers ! */ if (usb_endpoint_xfer_isoc(&urb->ep->desc)) { WARN_ON(1); return -EINVAL; } n = dma_map_sg( hcd->self.sysdev, urb->sg, urb->num_sgs, dir); if (n <= 0) ret = -EAGAIN; else urb->transfer_flags |= URB_DMA_MAP_SG; urb->num_mapped_sgs = n; if (n != urb->num_sgs) urb->transfer_flags |= URB_DMA_SG_COMBINED; } else if (urb->sg) { struct scatterlist *sg = urb->sg; urb->transfer_dma = dma_map_page( hcd->self.sysdev, sg_page(sg), sg->offset, urb->transfer_buffer_length, dir); if (dma_mapping_error(hcd->self.sysdev, urb->transfer_dma)) ret = -EAGAIN; else urb->transfer_flags |= URB_DMA_MAP_PAGE; } else if (is_vmalloc_addr(urb->transfer_buffer)) { WARN_ONCE(1, "transfer buffer not dma capable\n"); ret = -EAGAIN; } else if (object_is_on_stack(urb->transfer_buffer)) { WARN_ONCE(1, "transfer buffer is on stack\n"); ret = -EAGAIN; } else { urb->transfer_dma = dma_map_single( hcd->self.sysdev, urb->transfer_buffer, urb->transfer_buffer_length, dir); if (dma_mapping_error(hcd->self.sysdev, urb->transfer_dma)) ret = -EAGAIN; else urb->transfer_flags |= URB_DMA_MAP_SINGLE; } } else if (hcd->driver->flags & HCD_LOCAL_MEM) { ret = hcd_alloc_coherent( urb->dev->bus, mem_flags, &urb->transfer_dma, &urb->transfer_buffer, urb->transfer_buffer_length, dir); if (ret == 0) urb->transfer_flags |= URB_MAP_LOCAL; } if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL))) usb_hcd_unmap_urb_for_dma(hcd, urb); } return ret; } EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma); /*-------------------------------------------------------------------------*/ /* 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 */ int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags) { int status; struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus); /* increment urb's reference count as part of giving it to the HCD * (which will control it). HCD guarantees that it either returns * an error or calls giveback(), but not both. */ usb_get_urb(urb); atomic_inc(&urb->use_count); atomic_inc(&urb->dev->urbnum); usbmon_urb_submit(&hcd->self, urb); /* NOTE requirements on root-hub callers (usbfs and the hub * driver, for now): URBs' urb->transfer_buffer must be * valid and usb_buffer_{sync,unmap}() not be needed, since * they could clobber root hub response data. Also, control * URBs must be submitted in process context with interrupts * enabled. */ if (is_root_hub(urb->dev)) { status = rh_urb_enqueue(hcd, urb); } else { status = map_urb_for_dma(hcd, urb, mem_flags); if (likely(status == 0)) { status = hcd->driver->urb_enqueue(hcd, urb, mem_flags); if (unlikely(status)) unmap_urb_for_dma(hcd, urb); } } if (unlikely(status)) { usbmon_urb_submit_error(&hcd->self, urb, status); urb->hcpriv = NULL; INIT_LIST_HEAD(&urb->urb_list); atomic_dec(&urb->use_count); atomic_dec(&urb->dev->urbnum); if (atomic_read(&urb->reject)) wake_up(&usb_kill_urb_queue); usb_put_urb(urb); } return status; } /*-------------------------------------------------------------------------*/ /* 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 status) { int value; if (is_root_hub(urb->dev)) value = usb_rh_urb_dequeue(hcd, urb, status); 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, status); } return value; } /* * called in any context * * caller guarantees urb won't be recycled till both unlink() * and the urb's completion function return */ int usb_hcd_unlink_urb (struct urb *urb, int status) { struct usb_hcd *hcd; struct usb_device *udev = urb->dev; int retval = -EIDRM; unsigned long flags; /* Prevent the device and bus from going away while * the unlink is carried out. If they are already gone * then urb->use_count must be 0, since disconnected * devices can't have any active URBs. */ spin_lock_irqsave(&hcd_urb_unlink_lock, flags); if (atomic_read(&urb->use_count) > 0) { retval = 0; usb_get_dev(udev); } spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags); if (retval == 0) { hcd = bus_to_hcd(urb->dev->bus); retval = unlink1(hcd, urb, status); if (retval == 0) retval = -EINPROGRESS; else if (retval != -EIDRM && retval != -EBUSY) dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n", urb, retval); usb_put_dev(udev); } return retval; } /*-------------------------------------------------------------------------*/ static void __usb_hcd_giveback_urb(struct urb *urb) { struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus); struct usb_anchor *anchor = urb->anchor; int status = urb->unlinked; urb->hcpriv = NULL; if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) && urb->actual_length < urb->transfer_buffer_length && !status)) status = -EREMOTEIO; unmap_urb_for_dma(hcd, urb); usbmon_urb_complete(&hcd->self, urb, status); usb_anchor_suspend_wakeups(anchor); usb_unanchor_urb(urb); if (likely(status == 0)) usb_led_activity(USB_LED_EVENT_HOST); /* pass ownership to the completion handler */ urb->status = status; urb->complete(urb); usb_anchor_resume_wakeups(anchor); atomic_dec(&urb->use_count); if (unlikely(atomic_read(&urb->reject))) wake_up(&usb_kill_urb_queue); usb_put_urb(urb); } static void usb_giveback_urb_bh(unsigned long param) { struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param; struct list_head local_list; spin_lock_irq(&bh->lock); bh->running = true; restart: list_replace_init(&bh->head, &local_list); spin_unlock_irq(&bh->lock); while (!list_empty(&local_list)) { struct urb *urb; urb = list_entry(local_list.next, struct urb, urb_list); list_del_init(&urb->urb_list); bh->completing_ep = urb->ep; __usb_hcd_giveback_urb(urb); bh->completing_ep = NULL; } /* check if there are new URBs to giveback */ spin_lock_irq(&bh->lock); if (!list_empty(&bh->head)) goto restart; bh->running = false; spin_unlock_irq(&bh->lock); } /** * 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. * @status: completion status code for the URB. * 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. * * If @urb was unlinked, the value of @status will be overridden by * @urb->unlinked. Erroneous short transfers are detected in case * the HCD hasn't checked for them. */ void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status) { struct giveback_urb_bh *bh; bool running, high_prio_bh; /* pass status to tasklet via unlinked */ if (likely(!urb->unlinked)) urb->unlinked = status; if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) { __usb_hcd_giveback_urb(urb); return; } if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) { bh = &hcd->high_prio_bh; high_prio_bh = true; } else { bh = &hcd->low_prio_bh; high_prio_bh = false; } spin_lock(&bh->lock); list_add_tail(&urb->urb_list, &bh->head); running = bh->running; spin_unlock(&bh->lock); if (running) ; else if (high_prio_bh) tasklet_hi_schedule(&bh->bh); else tasklet_schedule(&bh->bh); } EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb); /*-------------------------------------------------------------------------*/ /* Cancel all URBs pending on this endpoint and wait for the endpoint's * queue to drain completely. The caller must first insure that no more * URBs can be submitted for this endpoint. */ void usb_hcd_flush_endpoint(struct usb_device *udev, struct usb_host_endpoint *ep) { struct usb_hcd *hcd; struct urb *urb; if (!ep) return; might_sleep(); hcd = bus_to_hcd(udev->bus); /* No more submits can occur */ spin_lock_irq(&hcd_urb_list_lock); rescan: list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) { int is_in; if (urb->unlinked) continue; usb_get_urb (urb); is_in = usb_urb_dir_in(urb); spin_unlock(&hcd_urb_list_lock); /* kick hcd */ unlink1(hcd, urb, -ESHUTDOWN); dev_dbg (hcd->self.controller, "shutdown urb %pK ep%d%s-%s\n", urb, usb_endpoint_num(&ep->desc), is_in ? "in" : "out", usb_ep_type_string(usb_endpoint_type(&ep->desc))); usb_put_urb (urb); /* list contents may have changed */ spin_lock(&hcd_urb_list_lock); goto rescan; } spin_unlock_irq(&hcd_urb_list_lock); /* Wait until the endpoint queue is completely empty */ while (!list_empty (&ep->urb_list)) { spin_lock_irq(&hcd_urb_list_lock); /* The list may have changed while we acquired the spinlock */ urb = NULL; if (!list_empty (&ep->urb_list)) { urb = list_entry (ep->urb_list.prev, struct urb, urb_list); usb_get_urb (urb); } spin_unlock_irq(&hcd_urb_list_lock); if (urb) { usb_kill_urb (urb); usb_put_urb (urb); } } } /** * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds * the bus bandwidth * @udev: target &usb_device * @new_config: new configuration to install * @cur_alt: the current alternate interface setting * @new_alt: alternate interface setting that is being installed * * To change configurations, pass in the new configuration in new_config, * and pass NULL for cur_alt and new_alt. * * To reset a device's configuration (put the device in the ADDRESSED state), * pass in NULL for new_config, cur_alt, and new_alt. * * To change alternate interface settings, pass in NULL for new_config, * pass in the current alternate interface setting in cur_alt, * and pass in the new alternate interface setting in new_alt. * * Return: An error if the requested bandwidth change exceeds the * bus bandwidth or host controller internal resources. */ int usb_hcd_alloc_bandwidth(struct usb_device *udev, struct usb_host_config *new_config, struct usb_host_interface *cur_alt, struct usb_host_interface *new_alt) { int num_intfs, i, j; struct usb_host_interface *alt = NULL; int ret = 0; struct usb_hcd *hcd; struct usb_host_endpoint *ep; hcd = bus_to_hcd(udev->bus); if (!hcd->driver->check_bandwidth) return 0; /* Configuration is being removed - set configuration 0 */ if (!new_config && !cur_alt) { for (i = 1; i < 16; ++i) { ep = udev->ep_out[i]; if (ep) hcd->driver->drop_endpoint(hcd, udev, ep); ep = udev->ep_in[i]; if (ep) hcd->driver->drop_endpoint(hcd, udev, ep); } hcd->driver->check_bandwidth(hcd, udev); return 0; } /* Check if the HCD says there's enough bandwidth. Enable all endpoints * each interface's alt setting 0 and ask the HCD to check the bandwidth * of the bus. There will always be bandwidth for endpoint 0, so it's * ok to exclude it. */ if (new_config) { num_intfs = new_config->desc.bNumInterfaces; /* Remove endpoints (except endpoint 0, which is always on the * schedule) from the old config from the schedule */ for (i = 1; i < 16; ++i) { ep = udev->ep_out[i]; if (ep) { ret = hcd->driver->drop_endpoint(hcd, udev, ep); if (ret < 0) goto reset; } ep = udev->ep_in[i]; if (ep) { ret = hcd->driver->drop_endpoint(hcd, udev, ep); if (ret < 0) goto reset; } } for (i = 0; i < num_intfs; ++i) { struct usb_host_interface *first_alt; int iface_num; first_alt = &new_config->intf_cache[i]->altsetting[0]; iface_num = first_alt->desc.bInterfaceNumber; /* Set up endpoints for alternate interface setting 0 */ alt = usb_find_alt_setting(new_config, iface_num, 0); if (!alt) /* No alt setting 0? Pick the first setting. */ alt = first_alt; for (j = 0; j < alt->desc.bNumEndpoints; j++) { ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]); if (ret < 0) goto reset; } } } if (cur_alt && new_alt) { struct usb_interface *iface = usb_ifnum_to_if(udev, cur_alt->desc.bInterfaceNumber); if (!iface) return -EINVAL; if (iface->resetting_device) { /* * The USB core just reset the device, so the xHCI host * and the device will think alt setting 0 is installed. * However, the USB core will pass in the alternate * setting installed before the reset as cur_alt. Dig * out the alternate setting 0 structure, or the first * alternate setting if a broken device doesn't have alt * setting 0. */ cur_alt = usb_altnum_to_altsetting(iface, 0); if (!cur_alt) cur_alt = &iface->altsetting[0]; } /* Drop all the endpoints in the current alt setting */ for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) { ret = hcd->driver->drop_endpoint(hcd, udev, &cur_alt->endpoint[i]); if (ret < 0) goto reset; } /* Add all the endpoints in the new alt setting */ for (i = 0; i < new_alt->desc.bNumEndpoints; i++) { ret = hcd->driver->add_endpoint(hcd, udev, &new_alt->endpoint[i]); if (ret < 0) goto reset; } } ret = hcd->driver->check_bandwidth(hcd, udev); reset: if (ret < 0) hcd->driver->reset_bandwidth(hcd, udev); return ret; } /* Disables the endpoint: synchronizes with the hcd to make sure all * endpoint state is gone from hardware. usb_hcd_flush_endpoint() must * have been called previously. 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. */ void usb_hcd_disable_endpoint(struct usb_device *udev, struct usb_host_endpoint *ep) { struct usb_hcd *hcd; might_sleep(); hcd = bus_to_hcd(udev->bus); if (hcd->driver->endpoint_disable) hcd->driver->endpoint_disable(hcd, ep); } /** * usb_hcd_reset_endpoint - reset host endpoint state * @udev: USB device. * @ep: the endpoint to reset. * * Resets any host endpoint state such as the toggle bit, sequence * number and current window. */ void usb_hcd_reset_endpoint(struct usb_device *udev, struct usb_host_endpoint *ep) { struct usb_hcd *hcd = bus_to_hcd(udev->bus); if (hcd->driver->endpoint_reset) hcd->driver->endpoint_reset(hcd, ep); else { int epnum = usb_endpoint_num(&ep->desc); int is_out = usb_endpoint_dir_out(&ep->desc); int is_control = usb_endpoint_xfer_control(&ep->desc); usb_settoggle(udev, epnum, is_out, 0); if (is_control) usb_settoggle(udev, epnum, !is_out, 0); } } /** * usb_alloc_streams - allocate bulk endpoint stream IDs. * @interface: alternate setting that includes all endpoints. * @eps: array of endpoints that need streams. * @num_eps: number of endpoints in the array. * @num_streams: number of streams to allocate. * @mem_flags: flags hcd should use to allocate memory. * * Sets up a group of bulk endpoints to have @num_streams stream IDs available. * Drivers may queue multiple transfers to different stream IDs, which may * complete in a different order than they were queued. * * Return: On success, the number of allocated streams. On failure, a negative * error code. */ int usb_alloc_streams(struct usb_interface *interface, struct usb_host_endpoint **eps, unsigned int num_eps, unsigned int num_streams, gfp_t mem_flags) { struct usb_hcd *hcd; struct usb_device *dev; int i, ret; dev = interface_to_usbdev(interface); hcd = bus_to_hcd(dev->bus); if (!hcd->driver->alloc_streams || !hcd->driver->free_streams) return -EINVAL; if (dev->speed < USB_SPEED_SUPER) return -EINVAL; if (dev->state < USB_STATE_CONFIGURED) return -ENODEV; for (i = 0; i < num_eps; i++) { /* Streams only apply to bulk endpoints. */ if (!usb_endpoint_xfer_bulk(&eps[i]->desc)) return -EINVAL; /* Re-alloc is not allowed */ if (eps[i]->streams) return -EINVAL; } ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps, num_streams, mem_flags); if (ret < 0) return ret; for (i = 0; i < num_eps; i++) eps[i]->streams = ret; return ret; } EXPORT_SYMBOL_GPL(usb_alloc_streams); /** * usb_free_streams - free bulk endpoint stream IDs. * @interface: alternate setting that includes all endpoints. * @eps: array of endpoints to remove streams from. * @num_eps: number of endpoints in the array. * @mem_flags: flags hcd should use to allocate memory. * * Reverts a group of bulk endpoints back to not using stream IDs. * Can fail if we are given bad arguments, or HCD is broken. * * Return: 0 on success. On failure, a negative error code. */ int usb_free_streams(struct usb_interface *interface, struct usb_host_endpoint **eps, unsigned int num_eps, gfp_t mem_flags) { struct usb_hcd *hcd; struct usb_device *dev; int i, ret; dev = interface_to_usbdev(interface); hcd = bus_to_hcd(dev->bus); if (dev->speed < USB_SPEED_SUPER) return -EINVAL; /* Double-free is not allowed */ for (i = 0; i < num_eps; i++) if (!eps[i] || !eps[i]->streams) return -EINVAL; ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags); if (ret < 0) return ret; for (i = 0; i < num_eps; i++) eps[i]->streams = 0; return ret; } EXPORT_SYMBOL_GPL(usb_free_streams); /* Protect against drivers that try to unlink URBs after the device * is gone, by waiting until all unlinks for @udev are finished. * Since we don't currently track URBs by device, simply wait until * nothing is running in the locked region of usb_hcd_unlink_urb(). */ void usb_hcd_synchronize_unlinks(struct usb_device *udev) { spin_lock_irq(&hcd_urb_unlink_lock); spin_unlock_irq(&hcd_urb_unlink_lock); } /*-------------------------------------------------------------------------*/ /* called in any context */ int usb_hcd_get_frame_number (struct usb_device *udev) { struct usb_hcd *hcd = bus_to_hcd(udev->bus); if (!HCD_RH_RUNNING(hcd)) return -ESHUTDOWN; return hcd->driver->get_frame_number (hcd); } /*-------------------------------------------------------------------------*/ #ifdef CONFIG_PM int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg) { struct usb_hcd *hcd = bus_to_hcd(rhdev->bus); int status; int old_state = hcd->state; dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n", (PMSG_IS_AUTO(msg) ? "auto-" : ""), rhdev->do_remote_wakeup); if (HCD_DEAD(hcd)) { dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend"); return 0; } if (!hcd->driver->bus_suspend) { status = -ENOENT; } else { clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); hcd->state = HC_STATE_QUIESCING; status = hcd->driver->bus_suspend(hcd); } if (status == 0) { usb_set_device_state(rhdev, USB_STATE_SUSPENDED); hcd->state = HC_STATE_SUSPENDED; if (!PMSG_IS_AUTO(msg)) usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub); /* Did we race with a root-hub wakeup event? */ if (rhdev->do_remote_wakeup) { char buffer[6]; status = hcd->driver->hub_status_data(hcd, buffer); if (status != 0) { dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n"); hcd_bus_resume(rhdev, PMSG_AUTO_RESUME); status = -EBUSY; } } } else { spin_lock_irq(&hcd_root_hub_lock); if (!HCD_DEAD(hcd)) { set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); hcd->state = old_state; } spin_unlock_irq(&hcd_root_hub_lock); dev_dbg(&rhdev->dev, "bus %s fail, err %d\n", "suspend", status); } return status; } int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg) { struct usb_hcd *hcd = bus_to_hcd(rhdev->bus); int status; int old_state = hcd->state; dev_dbg(&rhdev->dev, "usb %sresume\n", (PMSG_IS_AUTO(msg) ? "auto-" : "")); if (HCD_DEAD(hcd)) { dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume"); return 0; } if (!PMSG_IS_AUTO(msg)) { status = usb_phy_roothub_resume(hcd->self.sysdev, hcd->phy_roothub); if (status) return status; } if (!hcd->driver->bus_resume) return -ENOENT; if (HCD_RH_RUNNING(hcd)) return 0; hcd->state = HC_STATE_RESUMING; status = hcd->driver->bus_resume(hcd); clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags); if (status == 0) { struct usb_device *udev; int port1; spin_lock_irq(&hcd_root_hub_lock); if (!HCD_DEAD(hcd)) { usb_set_device_state(rhdev, rhdev->actconfig ? USB_STATE_CONFIGURED : USB_STATE_ADDRESS); set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); hcd->state = HC_STATE_RUNNING; } spin_unlock_irq(&hcd_root_hub_lock); /* * Check whether any of the enabled ports on the root hub are * unsuspended. If they are then a TRSMRCY delay is needed * (this is what the USB-2 spec calls a "global resume"). * Otherwise we can skip the delay. */ usb_hub_for_each_child(rhdev, port1, udev) { if (udev->state != USB_STATE_NOTATTACHED && !udev->port_is_suspended) { usleep_range(10000, 11000); /* TRSMRCY */ break; } } } else { hcd->state = old_state; usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub); dev_dbg(&rhdev->dev, "bus %s fail, err %d\n", "resume", status); if (status != -ESHUTDOWN) usb_hc_died(hcd); } return status; } /* Workqueue routine for root-hub remote wakeup */ static void hcd_resume_work(struct work_struct *work) { struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work); struct usb_device *udev = hcd->self.root_hub; usb_remote_wakeup(udev); } /** * 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. The routine submits a workqueue request * 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) { pm_wakeup_event(&hcd->self.root_hub->dev, 0); set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags); queue_work(pm_wq, &hcd->wakeup_work); } spin_unlock_irqrestore (&hcd_root_hub_lock, flags); } EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub); #endif /* CONFIG_PM */ /*-------------------------------------------------------------------------*/ #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 * hub_wq 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. * * Return: 0 if successful. */ 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 = bus_to_hcd(bus); if (port_num && hcd->driver->start_port_reset) status = hcd->driver->start_port_reset(hcd, port_num); /* allocate hub_wq 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_GPL(usb_bus_start_enum); #endif /*-------------------------------------------------------------------------*/ /** * 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 * * If the controller isn't HALTed, calls the driver's irq handler. * Checks whether the controller is now dead. * * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise. */ irqreturn_t usb_hcd_irq (int irq, void *__hcd) { struct usb_hcd *hcd = __hcd; irqreturn_t rc; if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd))) rc = IRQ_NONE; else if (hcd->driver->irq(hcd) == IRQ_NONE) rc = IRQ_NONE; else rc = IRQ_HANDLED; return rc; } EXPORT_SYMBOL_GPL(usb_hcd_irq); /*-------------------------------------------------------------------------*/ /* Workqueue routine for when the root-hub has died. */ static void hcd_died_work(struct work_struct *work) { struct usb_hcd *hcd = container_of(work, struct usb_hcd, died_work); static char *env[] = { "ERROR=DEAD", NULL }; /* Notify user space that the host controller has died */ kobject_uevent_env(&hcd->self.root_hub->dev.kobj, KOBJ_OFFLINE, env); } /** * 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. * * Only call this function with the primary HCD. */ 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); clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); set_bit(HCD_FLAG_DEAD, &hcd->flags); if (hcd->rh_registered) { clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); /* make hub_wq clean up old urbs and devices */ usb_set_device_state (hcd->self.root_hub, USB_STATE_NOTATTACHED); usb_kick_hub_wq(hcd->self.root_hub); } if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) { hcd = hcd->shared_hcd; clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); set_bit(HCD_FLAG_DEAD, &hcd->flags); if (hcd->rh_registered) { clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); /* make hub_wq clean up old urbs and devices */ usb_set_device_state(hcd->self.root_hub, USB_STATE_NOTATTACHED); usb_kick_hub_wq(hcd->self.root_hub); } } /* Handle the case where this function gets called with a shared HCD */ if (usb_hcd_is_primary_hcd(hcd)) schedule_work(&hcd->died_work); else schedule_work(&hcd->primary_hcd->died_work); spin_unlock_irqrestore (&hcd_root_hub_lock, flags); /* Make sure that the other roothub is also deallocated. */ } EXPORT_SYMBOL_GPL (usb_hc_died); /*-------------------------------------------------------------------------*/ static void init_giveback_urb_bh(struct giveback_urb_bh *bh) { spin_lock_init(&bh->lock); INIT_LIST_HEAD(&bh->head); tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh); } struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver, struct device *sysdev, struct device *dev, const char *bus_name, struct usb_hcd *primary_hcd) { struct usb_hcd *hcd; hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL); if (!hcd) return NULL; if (primary_hcd == NULL) { hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex), GFP_KERNEL); if (!hcd->address0_mutex) { kfree(hcd); dev_dbg(dev, "hcd address0 mutex alloc failed\n"); return NULL; } mutex_init(hcd->address0_mutex); hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex), GFP_KERNEL); if (!hcd->bandwidth_mutex) { kfree(hcd->address0_mutex); kfree(hcd); dev_dbg(dev, "hcd bandwidth mutex alloc failed\n"); return NULL; } mutex_init(hcd->bandwidth_mutex); dev_set_drvdata(dev, hcd); } else { mutex_lock(&usb_port_peer_mutex); hcd->address0_mutex = primary_hcd->address0_mutex; hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex; hcd->primary_hcd = primary_hcd; primary_hcd->primary_hcd = primary_hcd; hcd->shared_hcd = primary_hcd; primary_hcd->shared_hcd = hcd; mutex_unlock(&usb_port_peer_mutex); } kref_init(&hcd->kref); usb_bus_init(&hcd->self); hcd->self.controller = dev; hcd->self.sysdev = sysdev; hcd->self.bus_name = bus_name; hcd->self.uses_dma = (sysdev->dma_mask != NULL); timer_setup(&hcd->rh_timer, rh_timer_func, 0); #ifdef CONFIG_PM INIT_WORK(&hcd->wakeup_work, hcd_resume_work); #endif INIT_WORK(&hcd->died_work, hcd_died_work); hcd->driver = driver; hcd->speed = driver->flags & HCD_MASK; hcd->product_desc = (driver->product_desc) ? driver->product_desc : "USB Host Controller"; return hcd; } EXPORT_SYMBOL_GPL(__usb_create_hcd); /** * usb_create_shared_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 * @primary_hcd: a pointer to the usb_hcd structure that is sharing the * PCI device. Only allocate certain resources for the primary HCD * 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. * * Return: On success, a pointer to the created and initialized HCD structure. * On failure (e.g. if memory is unavailable), %NULL. */ struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver, struct device *dev, const char *bus_name, struct usb_hcd *primary_hcd) { return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd); } EXPORT_SYMBOL_GPL(usb_create_shared_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. * * Return: On success, a pointer to the created and initialized HCD * structure. On failure (e.g. if memory is unavailable), %NULL. */ struct usb_hcd *usb_create_hcd(const struct hc_driver *driver, struct device *dev, const char *bus_name) { return __usb_create_hcd(driver, dev, dev, bus_name, NULL); } EXPORT_SYMBOL_GPL(usb_create_hcd); /* * Roothubs that share one PCI device must also share the bandwidth mutex. * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is * deallocated. * * Make sure to deallocate the bandwidth_mutex only when the last HCD is * freed. When hcd_release() is called for either hcd in a peer set, * invalidate the peer's ->shared_hcd and ->primary_hcd pointers. */ static void hcd_release(struct kref *kref) { struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref); mutex_lock(&usb_port_peer_mutex); if (hcd->shared_hcd) { struct usb_hcd *peer = hcd->shared_hcd; peer->shared_hcd = NULL; peer->primary_hcd = NULL; } else { kfree(hcd->address0_mutex); kfree(hcd->bandwidth_mutex); } mutex_unlock(&usb_port_peer_mutex); kfree(hcd); } struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd) { if (hcd) kref_get (&hcd->kref); return hcd; } EXPORT_SYMBOL_GPL(usb_get_hcd); void usb_put_hcd (struct usb_hcd *hcd) { if (hcd) kref_put (&hcd->kref, hcd_release); } EXPORT_SYMBOL_GPL(usb_put_hcd); int usb_hcd_is_primary_hcd(struct usb_hcd *hcd) { if (!hcd->primary_hcd) return 1; return hcd == hcd->primary_hcd; } EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd); int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1) { if (!hcd->driver->find_raw_port_number) return port1; return hcd->driver->find_raw_port_number(hcd, port1); } static int usb_hcd_request_irqs(struct usb_hcd *hcd, unsigned int irqnum, unsigned long irqflags) { int retval; if (hcd->driver->irq) { snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d", hcd->driver->description, hcd->self.busnum); retval = request_irq(irqnum, &usb_hcd_irq, irqflags, hcd->irq_descr, hcd); if (retval != 0) { dev_err(hcd->self.controller, "request interrupt %d failed\n", irqnum); return retval; } hcd->irq = irqnum; dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum, (hcd->driver->flags & HCD_MEMORY) ? "io mem" : "io base", (unsigned long long)hcd->rsrc_start); } else { hcd->irq = 0; 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); } return 0; } /* * Before we free this root hub, flush in-flight peering attempts * and disable peer lookups */ static void usb_put_invalidate_rhdev(struct usb_hcd *hcd) { struct usb_device *rhdev; mutex_lock(&usb_port_peer_mutex); rhdev = hcd->self.root_hub; hcd->self.root_hub = NULL; mutex_unlock(&usb_port_peer_mutex); usb_put_dev(rhdev); } /** * 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; if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) { hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev); if (IS_ERR(hcd->phy_roothub)) return PTR_ERR(hcd->phy_roothub); retval = usb_phy_roothub_init(hcd->phy_roothub); if (retval) return retval; retval = usb_phy_roothub_set_mode(hcd->phy_roothub, PHY_MODE_USB_HOST_SS); if (retval) retval = usb_phy_roothub_set_mode(hcd->phy_roothub, PHY_MODE_USB_HOST); if (retval) goto err_usb_phy_roothub_power_on; retval = usb_phy_roothub_power_on(hcd->phy_roothub); if (retval) goto err_usb_phy_roothub_power_on; } dev_info(hcd->self.controller, "%s\n", hcd->product_desc); switch (authorized_default) { case USB_AUTHORIZE_NONE: hcd->dev_policy = USB_DEVICE_AUTHORIZE_NONE; break; case USB_AUTHORIZE_ALL: hcd->dev_policy = USB_DEVICE_AUTHORIZE_ALL; break; case USB_AUTHORIZE_INTERNAL: hcd->dev_policy = USB_DEVICE_AUTHORIZE_INTERNAL; break; case USB_AUTHORIZE_WIRED: default: hcd->dev_policy = hcd->wireless ? USB_DEVICE_AUTHORIZE_NONE : USB_DEVICE_AUTHORIZE_ALL; break; } set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags); /* per default all interfaces are authorized */ set_bit(HCD_FLAG_INTF_AUTHORIZED, &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 hub_wq * starts talking to them. (Note, bus id is assigned early too.) */ retval = hcd_buffer_create(hcd); if (retval != 0) { dev_dbg(hcd->self.sysdev, "pool alloc failed\n"); goto err_create_buf; } retval = usb_register_bus(&hcd->self); if (retval < 0) goto err_register_bus; rhdev = usb_alloc_dev(NULL, &hcd->self, 0); if (rhdev == NULL) { dev_err(hcd->self.sysdev, "unable to allocate root hub\n"); retval = -ENOMEM; goto err_allocate_root_hub; } mutex_lock(&usb_port_peer_mutex); hcd->self.root_hub = rhdev; mutex_unlock(&usb_port_peer_mutex); rhdev->rx_lanes = 1; rhdev->tx_lanes = 1; switch (hcd->speed) { case HCD_USB11: rhdev->speed = USB_SPEED_FULL; break; case HCD_USB2: rhdev->speed = USB_SPEED_HIGH; break; case HCD_USB25: rhdev->speed = USB_SPEED_WIRELESS; break; case HCD_USB3: rhdev->speed = USB_SPEED_SUPER; break; case HCD_USB32: rhdev->rx_lanes = 2; rhdev->tx_lanes = 2; /* fall through */ case HCD_USB31: rhdev->speed = USB_SPEED_SUPER_PLUS; break; default: retval = -EINVAL; goto err_set_rh_speed; } /* wakeup flag init defaults to "everything works" for root hubs, * but drivers can override it in reset() if needed, along with * recording the overall controller's system wakeup capability. */ device_set_wakeup_capable(&rhdev->dev, 1); /* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is * registered. But since the controller can die at any time, * let's initialize the flag before touching the hardware. */ set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); /* "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); if (retval < 0) { dev_err(hcd->self.controller, "can't setup: %d\n", retval); goto err_hcd_driver_setup; } } hcd->rh_pollable = 1; /* NOTE: root hub and controller capabilities may not be the same */ if (device_can_wakeup(hcd->self.controller) && device_can_wakeup(&hcd->self.root_hub->dev)) dev_dbg(hcd->self.controller, "supports USB remote wakeup\n"); /* initialize tasklets */ init_giveback_urb_bh(&hcd->high_prio_bh); init_giveback_urb_bh(&hcd->low_prio_bh); /* enable irqs just before we start the controller, * if the BIOS provides legacy PCI irqs. */ if (usb_hcd_is_primary_hcd(hcd) && irqnum) { retval = usb_hcd_request_irqs(hcd, irqnum, irqflags); if (retval) goto err_request_irq; } hcd->state = HC_STATE_RUNNING; retval = hcd->driver->start(hcd); if (retval < 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 */ retval = register_root_hub(hcd); if (retval != 0) goto err_register_root_hub; retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group); if (retval < 0) { printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n", retval); goto error_create_attr_group; } if (hcd->uses_new_polling && HCD_POLL_RH(hcd)) usb_hcd_poll_rh_status(hcd); return retval; error_create_attr_group: clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); if (HC_IS_RUNNING(hcd->state)) hcd->state = HC_STATE_QUIESCING; spin_lock_irq(&hcd_root_hub_lock); hcd->rh_registered = 0; spin_unlock_irq(&hcd_root_hub_lock); #ifdef CONFIG_PM cancel_work_sync(&hcd->wakeup_work); #endif cancel_work_sync(&hcd->died_work); mutex_lock(&usb_bus_idr_lock); usb_disconnect(&rhdev); /* Sets rhdev to NULL */ mutex_unlock(&usb_bus_idr_lock); err_register_root_hub: hcd->rh_pollable = 0; clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); del_timer_sync(&hcd->rh_timer); hcd->driver->stop(hcd); hcd->state = HC_STATE_HALT; clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); del_timer_sync(&hcd->rh_timer); err_hcd_driver_start: if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0) free_irq(irqnum, hcd); err_request_irq: err_hcd_driver_setup: err_set_rh_speed: usb_put_invalidate_rhdev(hcd); err_allocate_root_hub: usb_deregister_bus(&hcd->self); err_register_bus: hcd_buffer_destroy(hcd); err_create_buf: usb_phy_roothub_power_off(hcd->phy_roothub); err_usb_phy_roothub_power_on: usb_phy_roothub_exit(hcd->phy_roothub); return retval; } EXPORT_SYMBOL_GPL(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) { struct usb_device *rhdev = hcd->self.root_hub; dev_info(hcd->self.controller, "remove, state %x\n", hcd->state); usb_get_dev(rhdev); sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group); clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 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); #ifdef CONFIG_PM cancel_work_sync(&hcd->wakeup_work); #endif cancel_work_sync(&hcd->died_work); mutex_lock(&usb_bus_idr_lock); usb_disconnect(&rhdev); /* Sets rhdev to NULL */ mutex_unlock(&usb_bus_idr_lock); /* * tasklet_kill() isn't needed here because: * - driver's disconnect() called from usb_disconnect() should * make sure its URBs are completed during the disconnect() * callback * * - it is too late to run complete() here since driver may have * been removed already now */ /* Prevent any more root-hub status calls from the timer. * The HCD might still restart the timer (if a port status change * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke * the hub_status_data() callback. */ hcd->rh_pollable = 0; clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); del_timer_sync(&hcd->rh_timer); hcd->driver->stop(hcd); hcd->state = HC_STATE_HALT; /* In case the HCD restarted the timer, stop it again. */ clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); del_timer_sync(&hcd->rh_timer); if (usb_hcd_is_primary_hcd(hcd)) { if (hcd->irq > 0) free_irq(hcd->irq, hcd); } usb_deregister_bus(&hcd->self); hcd_buffer_destroy(hcd); usb_phy_roothub_power_off(hcd->phy_roothub); usb_phy_roothub_exit(hcd->phy_roothub); usb_put_invalidate_rhdev(hcd); hcd->flags = 0; } EXPORT_SYMBOL_GPL(usb_remove_hcd); void usb_hcd_platform_shutdown(struct platform_device *dev) { struct usb_hcd *hcd = platform_get_drvdata(dev); /* No need for pm_runtime_put(), we're shutting down */ pm_runtime_get_sync(&dev->dev); if (hcd->driver->shutdown) hcd->driver->shutdown(hcd); } EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown); /*-------------------------------------------------------------------------*/ #if IS_ENABLED(CONFIG_USB_MON) const 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(const 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 || CONFIG_USB_MON_MODULE */