linux/drivers/usb/core/usb.c
Julius Werner 9b79091545 usb: ehci: Only sleep for post-resume handover if devices use persist
The current EHCI code sleeps a flat 110ms in the resume path if there
was a USB 1.1 device connected to its companion controller during
suspend, waiting for the device to reappear and reset so that it can be
handed back to the companion. This is necessary if the device uses
persist, so that the companion controller can actually see it during its
own resume path.

However, if the device doesn't use persist, this is entirely
unnecessary. We might just as well ignore it and have the normal device
detection/reset/handoff code handle it asynchronously when it eventually
shows up. As USB 1.1 devices are almost exclusively HIDs these days (for
which persist has no value), this can allow distros to shave another
tenth of a second off their resume time.

In order to enable this optimization, the patch also adds a new
usb_for_each_dev() iterator that is exported by the USB core and wraps
bus_for_each_dev() with the logic to differentiate between struct
usb_device and struct usb_interface on the usb_bus_type bus.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20 11:28:55 -07:00

1108 lines
31 KiB
C

/*
* drivers/usb/core/usb.c
*
* (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 (new USB architecture)
* (C) Copyright Randy Dunlap 2000
* (C) Copyright David Brownell 2000-2004
* (C) Copyright Yggdrasil Computing, Inc. 2000
* (usb_device_id matching changes by Adam J. Richter)
* (C) Copyright Greg Kroah-Hartman 2002-2003
*
* NOTE! This is not actually a driver at all, rather this is
* just a collection of helper routines that implement the
* generic USB things that the real drivers can use..
*
* Think of this as a "USB library" rather than anything else.
* It should be considered a slave, with no callbacks. Callbacks
* are evil.
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/string.h>
#include <linux/bitops.h>
#include <linux/slab.h>
#include <linux/interrupt.h> /* for in_interrupt() */
#include <linux/kmod.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/errno.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include <linux/mutex.h>
#include <linux/workqueue.h>
#include <linux/debugfs.h>
#include <asm/io.h>
#include <linux/scatterlist.h>
#include <linux/mm.h>
#include <linux/dma-mapping.h>
#include "usb.h"
const char *usbcore_name = "usbcore";
static bool nousb; /* Disable USB when built into kernel image */
#ifdef CONFIG_PM_RUNTIME
static int usb_autosuspend_delay = 2; /* Default delay value,
* in seconds */
module_param_named(autosuspend, usb_autosuspend_delay, int, 0644);
MODULE_PARM_DESC(autosuspend, "default autosuspend delay");
#else
#define usb_autosuspend_delay 0
#endif
/**
* usb_find_alt_setting() - Given a configuration, find the alternate setting
* for the given interface.
* @config: the configuration to search (not necessarily the current config).
* @iface_num: interface number to search in
* @alt_num: alternate interface setting number to search for.
*
* Search the configuration's interface cache for the given alt setting.
*/
struct usb_host_interface *usb_find_alt_setting(
struct usb_host_config *config,
unsigned int iface_num,
unsigned int alt_num)
{
struct usb_interface_cache *intf_cache = NULL;
int i;
for (i = 0; i < config->desc.bNumInterfaces; i++) {
if (config->intf_cache[i]->altsetting[0].desc.bInterfaceNumber
== iface_num) {
intf_cache = config->intf_cache[i];
break;
}
}
if (!intf_cache)
return NULL;
for (i = 0; i < intf_cache->num_altsetting; i++)
if (intf_cache->altsetting[i].desc.bAlternateSetting == alt_num)
return &intf_cache->altsetting[i];
printk(KERN_DEBUG "Did not find alt setting %u for intf %u, "
"config %u\n", alt_num, iface_num,
config->desc.bConfigurationValue);
return NULL;
}
EXPORT_SYMBOL_GPL(usb_find_alt_setting);
/**
* usb_ifnum_to_if - get the interface object with a given interface number
* @dev: the device whose current configuration is considered
* @ifnum: the desired interface
*
* This walks the device descriptor for the currently active configuration
* and returns a pointer to the interface with that particular interface
* number, or null.
*
* Note that configuration descriptors are not required to assign interface
* numbers sequentially, so that it would be incorrect to assume that
* the first interface in that descriptor corresponds to interface zero.
* This routine helps device drivers avoid such mistakes.
* However, you should make sure that you do the right thing with any
* alternate settings available for this interfaces.
*
* Don't call this function unless you are bound to one of the interfaces
* on this device or you have locked the device!
*/
struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev,
unsigned ifnum)
{
struct usb_host_config *config = dev->actconfig;
int i;
if (!config)
return NULL;
for (i = 0; i < config->desc.bNumInterfaces; i++)
if (config->interface[i]->altsetting[0]
.desc.bInterfaceNumber == ifnum)
return config->interface[i];
return NULL;
}
EXPORT_SYMBOL_GPL(usb_ifnum_to_if);
/**
* usb_altnum_to_altsetting - get the altsetting structure with a given alternate setting number.
* @intf: the interface containing the altsetting in question
* @altnum: the desired alternate setting number
*
* This searches the altsetting array of the specified interface for
* an entry with the correct bAlternateSetting value and returns a pointer
* to that entry, or null.
*
* Note that altsettings need not be stored sequentially by number, so
* it would be incorrect to assume that the first altsetting entry in
* the array corresponds to altsetting zero. This routine helps device
* drivers avoid such mistakes.
*
* Don't call this function unless you are bound to the intf interface
* or you have locked the device!
*/
struct usb_host_interface *usb_altnum_to_altsetting(
const struct usb_interface *intf,
unsigned int altnum)
{
int i;
for (i = 0; i < intf->num_altsetting; i++) {
if (intf->altsetting[i].desc.bAlternateSetting == altnum)
return &intf->altsetting[i];
}
return NULL;
}
EXPORT_SYMBOL_GPL(usb_altnum_to_altsetting);
struct find_interface_arg {
int minor;
struct device_driver *drv;
};
static int __find_interface(struct device *dev, void *data)
{
struct find_interface_arg *arg = data;
struct usb_interface *intf;
if (!is_usb_interface(dev))
return 0;
if (dev->driver != arg->drv)
return 0;
intf = to_usb_interface(dev);
return intf->minor == arg->minor;
}
/**
* usb_find_interface - find usb_interface pointer for driver and device
* @drv: the driver whose current configuration is considered
* @minor: the minor number of the desired device
*
* This walks the bus device list and returns a pointer to the interface
* with the matching minor and driver. Note, this only works for devices
* that share the USB major number.
*/
struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor)
{
struct find_interface_arg argb;
struct device *dev;
argb.minor = minor;
argb.drv = &drv->drvwrap.driver;
dev = bus_find_device(&usb_bus_type, NULL, &argb, __find_interface);
/* Drop reference count from bus_find_device */
put_device(dev);
return dev ? to_usb_interface(dev) : NULL;
}
EXPORT_SYMBOL_GPL(usb_find_interface);
struct each_dev_arg {
void *data;
int (*fn)(struct usb_device *, void *);
};
static int __each_dev(struct device *dev, void *data)
{
struct each_dev_arg *arg = (struct each_dev_arg *)data;
/* There are struct usb_interface on the same bus, filter them out */
if (!is_usb_device(dev))
return 0;
return arg->fn(container_of(dev, struct usb_device, dev), arg->data);
}
/**
* usb_for_each_dev - iterate over all USB devices in the system
* @data: data pointer that will be handed to the callback function
* @fn: callback function to be called for each USB device
*
* Iterate over all USB devices and call @fn for each, passing it @data. If it
* returns anything other than 0, we break the iteration prematurely and return
* that value.
*/
int usb_for_each_dev(void *data, int (*fn)(struct usb_device *, void *))
{
struct each_dev_arg arg = {data, fn};
return bus_for_each_dev(&usb_bus_type, NULL, &arg, __each_dev);
}
EXPORT_SYMBOL_GPL(usb_for_each_dev);
/**
* usb_release_dev - free a usb device structure when all users of it are finished.
* @dev: device that's been disconnected
*
* Will be called only by the device core when all users of this usb device are
* done.
*/
static void usb_release_dev(struct device *dev)
{
struct usb_device *udev;
struct usb_hcd *hcd;
udev = to_usb_device(dev);
hcd = bus_to_hcd(udev->bus);
usb_destroy_configuration(udev);
usb_release_bos_descriptor(udev);
usb_put_hcd(hcd);
kfree(udev->product);
kfree(udev->manufacturer);
kfree(udev->serial);
kfree(udev);
}
static int usb_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
{
struct usb_device *usb_dev;
usb_dev = to_usb_device(dev);
if (add_uevent_var(env, "BUSNUM=%03d", usb_dev->bus->busnum))
return -ENOMEM;
if (add_uevent_var(env, "DEVNUM=%03d", usb_dev->devnum))
return -ENOMEM;
return 0;
}
#ifdef CONFIG_PM
/* USB device Power-Management thunks.
* There's no need to distinguish here between quiescing a USB device
* and powering it down; the generic_suspend() routine takes care of
* it by skipping the usb_port_suspend() call for a quiesce. And for
* USB interfaces there's no difference at all.
*/
static int usb_dev_prepare(struct device *dev)
{
return 0; /* Implement eventually? */
}
static void usb_dev_complete(struct device *dev)
{
/* Currently used only for rebinding interfaces */
usb_resume_complete(dev);
}
static int usb_dev_suspend(struct device *dev)
{
return usb_suspend(dev, PMSG_SUSPEND);
}
static int usb_dev_resume(struct device *dev)
{
return usb_resume(dev, PMSG_RESUME);
}
static int usb_dev_freeze(struct device *dev)
{
return usb_suspend(dev, PMSG_FREEZE);
}
static int usb_dev_thaw(struct device *dev)
{
return usb_resume(dev, PMSG_THAW);
}
static int usb_dev_poweroff(struct device *dev)
{
return usb_suspend(dev, PMSG_HIBERNATE);
}
static int usb_dev_restore(struct device *dev)
{
return usb_resume(dev, PMSG_RESTORE);
}
static const struct dev_pm_ops usb_device_pm_ops = {
.prepare = usb_dev_prepare,
.complete = usb_dev_complete,
.suspend = usb_dev_suspend,
.resume = usb_dev_resume,
.freeze = usb_dev_freeze,
.thaw = usb_dev_thaw,
.poweroff = usb_dev_poweroff,
.restore = usb_dev_restore,
#ifdef CONFIG_PM_RUNTIME
.runtime_suspend = usb_runtime_suspend,
.runtime_resume = usb_runtime_resume,
.runtime_idle = usb_runtime_idle,
#endif
};
#endif /* CONFIG_PM */
static char *usb_devnode(struct device *dev,
umode_t *mode, kuid_t *uid, kgid_t *gid)
{
struct usb_device *usb_dev;
usb_dev = to_usb_device(dev);
return kasprintf(GFP_KERNEL, "bus/usb/%03d/%03d",
usb_dev->bus->busnum, usb_dev->devnum);
}
struct device_type usb_device_type = {
.name = "usb_device",
.release = usb_release_dev,
.uevent = usb_dev_uevent,
.devnode = usb_devnode,
#ifdef CONFIG_PM
.pm = &usb_device_pm_ops,
#endif
};
/* Returns 1 if @usb_bus is WUSB, 0 otherwise */
static unsigned usb_bus_is_wusb(struct usb_bus *bus)
{
struct usb_hcd *hcd = container_of(bus, struct usb_hcd, self);
return hcd->wireless;
}
/**
* usb_alloc_dev - usb device constructor (usbcore-internal)
* @parent: hub to which device is connected; null to allocate a root hub
* @bus: bus used to access the device
* @port1: one-based index of port; ignored for root hubs
* Context: !in_interrupt()
*
* Only hub drivers (including virtual root hub drivers for host
* controllers) should ever call this.
*
* This call may not be used in a non-sleeping context.
*/
struct usb_device *usb_alloc_dev(struct usb_device *parent,
struct usb_bus *bus, unsigned port1)
{
struct usb_device *dev;
struct usb_hcd *usb_hcd = bus_to_hcd(bus);
unsigned root_hub = 0;
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return NULL;
if (!usb_get_hcd(usb_hcd)) {
kfree(dev);
return NULL;
}
/* Root hubs aren't true devices, so don't allocate HCD resources */
if (usb_hcd->driver->alloc_dev && parent &&
!usb_hcd->driver->alloc_dev(usb_hcd, dev)) {
usb_put_hcd(bus_to_hcd(bus));
kfree(dev);
return NULL;
}
device_initialize(&dev->dev);
dev->dev.bus = &usb_bus_type;
dev->dev.type = &usb_device_type;
dev->dev.groups = usb_device_groups;
dev->dev.dma_mask = bus->controller->dma_mask;
set_dev_node(&dev->dev, dev_to_node(bus->controller));
dev->state = USB_STATE_ATTACHED;
dev->lpm_disable_count = 1;
atomic_set(&dev->urbnum, 0);
INIT_LIST_HEAD(&dev->ep0.urb_list);
dev->ep0.desc.bLength = USB_DT_ENDPOINT_SIZE;
dev->ep0.desc.bDescriptorType = USB_DT_ENDPOINT;
/* ep0 maxpacket comes later, from device descriptor */
usb_enable_endpoint(dev, &dev->ep0, false);
dev->can_submit = 1;
/* Save readable and stable topology id, distinguishing devices
* by location for diagnostics, tools, driver model, etc. The
* string is a path along hub ports, from the root. Each device's
* dev->devpath will be stable until USB is re-cabled, and hubs
* are often labeled with these port numbers. The name isn't
* as stable: bus->busnum changes easily from modprobe order,
* cardbus or pci hotplugging, and so on.
*/
if (unlikely(!parent)) {
dev->devpath[0] = '0';
dev->route = 0;
dev->dev.parent = bus->controller;
dev_set_name(&dev->dev, "usb%d", bus->busnum);
root_hub = 1;
} else {
/* match any labeling on the hubs; it's one-based */
if (parent->devpath[0] == '0') {
snprintf(dev->devpath, sizeof dev->devpath,
"%d", port1);
/* Root ports are not counted in route string */
dev->route = 0;
} else {
snprintf(dev->devpath, sizeof dev->devpath,
"%s.%d", parent->devpath, port1);
/* Route string assumes hubs have less than 16 ports */
if (port1 < 15)
dev->route = parent->route +
(port1 << ((parent->level - 1)*4));
else
dev->route = parent->route +
(15 << ((parent->level - 1)*4));
}
dev->dev.parent = &parent->dev;
dev_set_name(&dev->dev, "%d-%s", bus->busnum, dev->devpath);
/* hub driver sets up TT records */
}
dev->portnum = port1;
dev->bus = bus;
dev->parent = parent;
INIT_LIST_HEAD(&dev->filelist);
#ifdef CONFIG_PM
pm_runtime_set_autosuspend_delay(&dev->dev,
usb_autosuspend_delay * 1000);
dev->connect_time = jiffies;
dev->active_duration = -jiffies;
#endif
if (root_hub) /* Root hub always ok [and always wired] */
dev->authorized = 1;
else {
dev->authorized = usb_hcd->authorized_default;
dev->wusb = usb_bus_is_wusb(bus)? 1 : 0;
}
return dev;
}
/**
* usb_get_dev - increments the reference count of the usb device structure
* @dev: the device being referenced
*
* Each live reference to a device should be refcounted.
*
* Drivers for USB interfaces should normally record such references in
* their probe() methods, when they bind to an interface, and release
* them by calling usb_put_dev(), in their disconnect() methods.
*
* A pointer to the device with the incremented reference counter is returned.
*/
struct usb_device *usb_get_dev(struct usb_device *dev)
{
if (dev)
get_device(&dev->dev);
return dev;
}
EXPORT_SYMBOL_GPL(usb_get_dev);
/**
* usb_put_dev - release a use of the usb device structure
* @dev: device that's been disconnected
*
* Must be called when a user of a device is finished with it. When the last
* user of the device calls this function, the memory of the device is freed.
*/
void usb_put_dev(struct usb_device *dev)
{
if (dev)
put_device(&dev->dev);
}
EXPORT_SYMBOL_GPL(usb_put_dev);
/**
* usb_get_intf - increments the reference count of the usb interface structure
* @intf: the interface being referenced
*
* Each live reference to a interface must be refcounted.
*
* Drivers for USB interfaces should normally record such references in
* their probe() methods, when they bind to an interface, and release
* them by calling usb_put_intf(), in their disconnect() methods.
*
* A pointer to the interface with the incremented reference counter is
* returned.
*/
struct usb_interface *usb_get_intf(struct usb_interface *intf)
{
if (intf)
get_device(&intf->dev);
return intf;
}
EXPORT_SYMBOL_GPL(usb_get_intf);
/**
* usb_put_intf - release a use of the usb interface structure
* @intf: interface that's been decremented
*
* Must be called when a user of an interface is finished with it. When the
* last user of the interface calls this function, the memory of the interface
* is freed.
*/
void usb_put_intf(struct usb_interface *intf)
{
if (intf)
put_device(&intf->dev);
}
EXPORT_SYMBOL_GPL(usb_put_intf);
/* USB device locking
*
* USB devices and interfaces are locked using the semaphore in their
* embedded struct device. The hub driver guarantees that whenever a
* device is connected or disconnected, drivers are called with the
* USB device locked as well as their particular interface.
*
* Complications arise when several devices are to be locked at the same
* time. Only hub-aware drivers that are part of usbcore ever have to
* do this; nobody else needs to worry about it. The rule for locking
* is simple:
*
* When locking both a device and its parent, always lock the
* the parent first.
*/
/**
* usb_lock_device_for_reset - cautiously acquire the lock for a usb device structure
* @udev: device that's being locked
* @iface: interface bound to the driver making the request (optional)
*
* Attempts to acquire the device lock, but fails if the device is
* NOTATTACHED or SUSPENDED, or if iface is specified and the interface
* is neither BINDING nor BOUND. Rather than sleeping to wait for the
* lock, the routine polls repeatedly. This is to prevent deadlock with
* disconnect; in some drivers (such as usb-storage) the disconnect()
* or suspend() method will block waiting for a device reset to complete.
*
* Returns a negative error code for failure, otherwise 0.
*/
int usb_lock_device_for_reset(struct usb_device *udev,
const struct usb_interface *iface)
{
unsigned long jiffies_expire = jiffies + HZ;
if (udev->state == USB_STATE_NOTATTACHED)
return -ENODEV;
if (udev->state == USB_STATE_SUSPENDED)
return -EHOSTUNREACH;
if (iface && (iface->condition == USB_INTERFACE_UNBINDING ||
iface->condition == USB_INTERFACE_UNBOUND))
return -EINTR;
while (!usb_trylock_device(udev)) {
/* If we can't acquire the lock after waiting one second,
* we're probably deadlocked */
if (time_after(jiffies, jiffies_expire))
return -EBUSY;
msleep(15);
if (udev->state == USB_STATE_NOTATTACHED)
return -ENODEV;
if (udev->state == USB_STATE_SUSPENDED)
return -EHOSTUNREACH;
if (iface && (iface->condition == USB_INTERFACE_UNBINDING ||
iface->condition == USB_INTERFACE_UNBOUND))
return -EINTR;
}
return 0;
}
EXPORT_SYMBOL_GPL(usb_lock_device_for_reset);
/**
* usb_get_current_frame_number - return current bus frame number
* @dev: the device whose bus is being queried
*
* Returns the current frame number for the USB host controller
* used with the given USB device. This can be used when scheduling
* isochronous requests.
*
* Note that different kinds of host controller have different
* "scheduling horizons". While one type might support scheduling only
* 32 frames into the future, others could support scheduling up to
* 1024 frames into the future.
*/
int usb_get_current_frame_number(struct usb_device *dev)
{
return usb_hcd_get_frame_number(dev);
}
EXPORT_SYMBOL_GPL(usb_get_current_frame_number);
/*-------------------------------------------------------------------*/
/*
* __usb_get_extra_descriptor() finds a descriptor of specific type in the
* extra field of the interface and endpoint descriptor structs.
*/
int __usb_get_extra_descriptor(char *buffer, unsigned size,
unsigned char type, void **ptr)
{
struct usb_descriptor_header *header;
while (size >= sizeof(struct usb_descriptor_header)) {
header = (struct usb_descriptor_header *)buffer;
if (header->bLength < 2) {
printk(KERN_ERR
"%s: bogus descriptor, type %d length %d\n",
usbcore_name,
header->bDescriptorType,
header->bLength);
return -1;
}
if (header->bDescriptorType == type) {
*ptr = header;
return 0;
}
buffer += header->bLength;
size -= header->bLength;
}
return -1;
}
EXPORT_SYMBOL_GPL(__usb_get_extra_descriptor);
/**
* usb_alloc_coherent - allocate dma-consistent buffer for URB_NO_xxx_DMA_MAP
* @dev: device the buffer will be used with
* @size: requested buffer size
* @mem_flags: affect whether allocation may block
* @dma: used to return DMA address of buffer
*
* Return value is either null (indicating no buffer could be allocated), or
* the cpu-space pointer to a buffer that may be used to perform DMA to the
* specified device. Such cpu-space buffers are returned along with the DMA
* address (through the pointer provided).
*
* These buffers are used with URB_NO_xxx_DMA_MAP set in urb->transfer_flags
* to avoid behaviors like using "DMA bounce buffers", or thrashing IOMMU
* hardware during URB completion/resubmit. The implementation varies between
* platforms, depending on details of how DMA will work to this device.
* Using these buffers also eliminates cacheline sharing problems on
* architectures where CPU caches are not DMA-coherent. On systems without
* bus-snooping caches, these buffers are uncached.
*
* When the buffer is no longer used, free it with usb_free_coherent().
*/
void *usb_alloc_coherent(struct usb_device *dev, size_t size, gfp_t mem_flags,
dma_addr_t *dma)
{
if (!dev || !dev->bus)
return NULL;
return hcd_buffer_alloc(dev->bus, size, mem_flags, dma);
}
EXPORT_SYMBOL_GPL(usb_alloc_coherent);
/**
* usb_free_coherent - free memory allocated with usb_alloc_coherent()
* @dev: device the buffer was used with
* @size: requested buffer size
* @addr: CPU address of buffer
* @dma: DMA address of buffer
*
* This reclaims an I/O buffer, letting it be reused. The memory must have
* been allocated using usb_alloc_coherent(), and the parameters must match
* those provided in that allocation request.
*/
void usb_free_coherent(struct usb_device *dev, size_t size, void *addr,
dma_addr_t dma)
{
if (!dev || !dev->bus)
return;
if (!addr)
return;
hcd_buffer_free(dev->bus, size, addr, dma);
}
EXPORT_SYMBOL_GPL(usb_free_coherent);
/**
* usb_buffer_map - create DMA mapping(s) for an urb
* @urb: urb whose transfer_buffer/setup_packet will be mapped
*
* Return value is either null (indicating no buffer could be mapped), or
* the parameter. URB_NO_TRANSFER_DMA_MAP is
* added to urb->transfer_flags if the operation succeeds. If the device
* is connected to this system through a non-DMA controller, this operation
* always succeeds.
*
* This call would normally be used for an urb which is reused, perhaps
* as the target of a large periodic transfer, with usb_buffer_dmasync()
* calls to synchronize memory and dma state.
*
* Reverse the effect of this call with usb_buffer_unmap().
*/
#if 0
struct urb *usb_buffer_map(struct urb *urb)
{
struct usb_bus *bus;
struct device *controller;
if (!urb
|| !urb->dev
|| !(bus = urb->dev->bus)
|| !(controller = bus->controller))
return NULL;
if (controller->dma_mask) {
urb->transfer_dma = dma_map_single(controller,
urb->transfer_buffer, urb->transfer_buffer_length,
usb_pipein(urb->pipe)
? DMA_FROM_DEVICE : DMA_TO_DEVICE);
/* FIXME generic api broken like pci, can't report errors */
/* if (urb->transfer_dma == DMA_ADDR_INVALID) return 0; */
} else
urb->transfer_dma = ~0;
urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
return urb;
}
EXPORT_SYMBOL_GPL(usb_buffer_map);
#endif /* 0 */
/* XXX DISABLED, no users currently. If you wish to re-enable this
* XXX please determine whether the sync is to transfer ownership of
* XXX the buffer from device to cpu or vice verse, and thusly use the
* XXX appropriate _for_{cpu,device}() method. -DaveM
*/
#if 0
/**
* usb_buffer_dmasync - synchronize DMA and CPU view of buffer(s)
* @urb: urb whose transfer_buffer/setup_packet will be synchronized
*/
void usb_buffer_dmasync(struct urb *urb)
{
struct usb_bus *bus;
struct device *controller;
if (!urb
|| !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
|| !urb->dev
|| !(bus = urb->dev->bus)
|| !(controller = bus->controller))
return;
if (controller->dma_mask) {
dma_sync_single_for_cpu(controller,
urb->transfer_dma, urb->transfer_buffer_length,
usb_pipein(urb->pipe)
? DMA_FROM_DEVICE : DMA_TO_DEVICE);
if (usb_pipecontrol(urb->pipe))
dma_sync_single_for_cpu(controller,
urb->setup_dma,
sizeof(struct usb_ctrlrequest),
DMA_TO_DEVICE);
}
}
EXPORT_SYMBOL_GPL(usb_buffer_dmasync);
#endif
/**
* usb_buffer_unmap - free DMA mapping(s) for an urb
* @urb: urb whose transfer_buffer will be unmapped
*
* Reverses the effect of usb_buffer_map().
*/
#if 0
void usb_buffer_unmap(struct urb *urb)
{
struct usb_bus *bus;
struct device *controller;
if (!urb
|| !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
|| !urb->dev
|| !(bus = urb->dev->bus)
|| !(controller = bus->controller))
return;
if (controller->dma_mask) {
dma_unmap_single(controller,
urb->transfer_dma, urb->transfer_buffer_length,
usb_pipein(urb->pipe)
? DMA_FROM_DEVICE : DMA_TO_DEVICE);
}
urb->transfer_flags &= ~URB_NO_TRANSFER_DMA_MAP;
}
EXPORT_SYMBOL_GPL(usb_buffer_unmap);
#endif /* 0 */
#if 0
/**
* usb_buffer_map_sg - create scatterlist DMA mapping(s) for an endpoint
* @dev: device to which the scatterlist will be mapped
* @is_in: mapping transfer direction
* @sg: the scatterlist to map
* @nents: the number of entries in the scatterlist
*
* Return value is either < 0 (indicating no buffers could be mapped), or
* the number of DMA mapping array entries in the scatterlist.
*
* The caller is responsible for placing the resulting DMA addresses from
* the scatterlist into URB transfer buffer pointers, and for setting the
* URB_NO_TRANSFER_DMA_MAP transfer flag in each of those URBs.
*
* Top I/O rates come from queuing URBs, instead of waiting for each one
* to complete before starting the next I/O. This is particularly easy
* to do with scatterlists. Just allocate and submit one URB for each DMA
* mapping entry returned, stopping on the first error or when all succeed.
* Better yet, use the usb_sg_*() calls, which do that (and more) for you.
*
* This call would normally be used when translating scatterlist requests,
* rather than usb_buffer_map(), since on some hardware (with IOMMUs) it
* may be able to coalesce mappings for improved I/O efficiency.
*
* Reverse the effect of this call with usb_buffer_unmap_sg().
*/
int usb_buffer_map_sg(const struct usb_device *dev, int is_in,
struct scatterlist *sg, int nents)
{
struct usb_bus *bus;
struct device *controller;
if (!dev
|| !(bus = dev->bus)
|| !(controller = bus->controller)
|| !controller->dma_mask)
return -EINVAL;
/* FIXME generic api broken like pci, can't report errors */
return dma_map_sg(controller, sg, nents,
is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE) ? : -ENOMEM;
}
EXPORT_SYMBOL_GPL(usb_buffer_map_sg);
#endif
/* XXX DISABLED, no users currently. If you wish to re-enable this
* XXX please determine whether the sync is to transfer ownership of
* XXX the buffer from device to cpu or vice verse, and thusly use the
* XXX appropriate _for_{cpu,device}() method. -DaveM
*/
#if 0
/**
* usb_buffer_dmasync_sg - synchronize DMA and CPU view of scatterlist buffer(s)
* @dev: device to which the scatterlist will be mapped
* @is_in: mapping transfer direction
* @sg: the scatterlist to synchronize
* @n_hw_ents: the positive return value from usb_buffer_map_sg
*
* Use this when you are re-using a scatterlist's data buffers for
* another USB request.
*/
void usb_buffer_dmasync_sg(const struct usb_device *dev, int is_in,
struct scatterlist *sg, int n_hw_ents)
{
struct usb_bus *bus;
struct device *controller;
if (!dev
|| !(bus = dev->bus)
|| !(controller = bus->controller)
|| !controller->dma_mask)
return;
dma_sync_sg_for_cpu(controller, sg, n_hw_ents,
is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
}
EXPORT_SYMBOL_GPL(usb_buffer_dmasync_sg);
#endif
#if 0
/**
* usb_buffer_unmap_sg - free DMA mapping(s) for a scatterlist
* @dev: device to which the scatterlist will be mapped
* @is_in: mapping transfer direction
* @sg: the scatterlist to unmap
* @n_hw_ents: the positive return value from usb_buffer_map_sg
*
* Reverses the effect of usb_buffer_map_sg().
*/
void usb_buffer_unmap_sg(const struct usb_device *dev, int is_in,
struct scatterlist *sg, int n_hw_ents)
{
struct usb_bus *bus;
struct device *controller;
if (!dev
|| !(bus = dev->bus)
|| !(controller = bus->controller)
|| !controller->dma_mask)
return;
dma_unmap_sg(controller, sg, n_hw_ents,
is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
}
EXPORT_SYMBOL_GPL(usb_buffer_unmap_sg);
#endif
/* To disable USB, kernel command line is 'nousb' not 'usbcore.nousb' */
#ifdef MODULE
module_param(nousb, bool, 0444);
#else
core_param(nousb, nousb, bool, 0444);
#endif
/*
* for external read access to <nousb>
*/
int usb_disabled(void)
{
return nousb;
}
EXPORT_SYMBOL_GPL(usb_disabled);
/*
* Notifications of device and interface registration
*/
static int usb_bus_notify(struct notifier_block *nb, unsigned long action,
void *data)
{
struct device *dev = data;
switch (action) {
case BUS_NOTIFY_ADD_DEVICE:
if (dev->type == &usb_device_type)
(void) usb_create_sysfs_dev_files(to_usb_device(dev));
else if (dev->type == &usb_if_device_type)
usb_create_sysfs_intf_files(to_usb_interface(dev));
break;
case BUS_NOTIFY_DEL_DEVICE:
if (dev->type == &usb_device_type)
usb_remove_sysfs_dev_files(to_usb_device(dev));
else if (dev->type == &usb_if_device_type)
usb_remove_sysfs_intf_files(to_usb_interface(dev));
break;
}
return 0;
}
static struct notifier_block usb_bus_nb = {
.notifier_call = usb_bus_notify,
};
struct dentry *usb_debug_root;
EXPORT_SYMBOL_GPL(usb_debug_root);
static struct dentry *usb_debug_devices;
static int usb_debugfs_init(void)
{
usb_debug_root = debugfs_create_dir("usb", NULL);
if (!usb_debug_root)
return -ENOENT;
usb_debug_devices = debugfs_create_file("devices", 0444,
usb_debug_root, NULL,
&usbfs_devices_fops);
if (!usb_debug_devices) {
debugfs_remove(usb_debug_root);
usb_debug_root = NULL;
return -ENOENT;
}
return 0;
}
static void usb_debugfs_cleanup(void)
{
debugfs_remove(usb_debug_devices);
debugfs_remove(usb_debug_root);
}
/*
* Init
*/
static int __init usb_init(void)
{
int retval;
if (nousb) {
pr_info("%s: USB support disabled\n", usbcore_name);
return 0;
}
retval = usb_debugfs_init();
if (retval)
goto out;
usb_acpi_register();
retval = bus_register(&usb_bus_type);
if (retval)
goto bus_register_failed;
retval = bus_register_notifier(&usb_bus_type, &usb_bus_nb);
if (retval)
goto bus_notifier_failed;
retval = usb_major_init();
if (retval)
goto major_init_failed;
retval = usb_register(&usbfs_driver);
if (retval)
goto driver_register_failed;
retval = usb_devio_init();
if (retval)
goto usb_devio_init_failed;
retval = usb_hub_init();
if (retval)
goto hub_init_failed;
retval = usb_register_device_driver(&usb_generic_driver, THIS_MODULE);
if (!retval)
goto out;
usb_hub_cleanup();
hub_init_failed:
usb_devio_cleanup();
usb_devio_init_failed:
usb_deregister(&usbfs_driver);
driver_register_failed:
usb_major_cleanup();
major_init_failed:
bus_unregister_notifier(&usb_bus_type, &usb_bus_nb);
bus_notifier_failed:
bus_unregister(&usb_bus_type);
bus_register_failed:
usb_acpi_unregister();
usb_debugfs_cleanup();
out:
return retval;
}
/*
* Cleanup
*/
static void __exit usb_exit(void)
{
/* This will matter if shutdown/reboot does exitcalls. */
if (nousb)
return;
usb_deregister_device_driver(&usb_generic_driver);
usb_major_cleanup();
usb_deregister(&usbfs_driver);
usb_devio_cleanup();
usb_hub_cleanup();
bus_unregister_notifier(&usb_bus_type, &usb_bus_nb);
bus_unregister(&usb_bus_type);
usb_acpi_unregister();
usb_debugfs_cleanup();
}
subsys_initcall(usb_init);
module_exit(usb_exit);
MODULE_LICENSE("GPL");