diff options
Diffstat (limited to 'drivers/usb/core/usb.c')
-rw-r--r-- | drivers/usb/core/usb.c | 86 |
1 files changed, 81 insertions, 5 deletions
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c index 8f07b0516100..62368c4ed37a 100644 --- a/drivers/usb/core/usb.c +++ b/drivers/usb/core/usb.c @@ -398,6 +398,52 @@ int usb_for_each_dev(void *data, int (*fn)(struct usb_device *, void *)) } EXPORT_SYMBOL_GPL(usb_for_each_dev); +struct each_hub_arg { + void *data; + int (*fn)(struct device *, void *); +}; + +static int __each_hub(struct usb_device *hdev, void *data) +{ + struct each_hub_arg *arg = (struct each_hub_arg *)data; + struct usb_hub *hub; + int ret = 0; + int i; + + hub = usb_hub_to_struct_hub(hdev); + if (!hub) + return 0; + + mutex_lock(&usb_port_peer_mutex); + + for (i = 0; i < hdev->maxchild; i++) { + ret = arg->fn(&hub->ports[i]->dev, arg->data); + if (ret) + break; + } + + mutex_unlock(&usb_port_peer_mutex); + + return ret; +} + +/** + * usb_for_each_port - interate over all USB ports in the system + * @data: data pointer that will be handed to the callback function + * @fn: callback function to be called for each USB port + * + * Iterate over all USB ports 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_port(void *data, int (*fn)(struct device *, void *)) +{ + struct each_hub_arg arg = {data, fn}; + + return usb_for_each_dev(&arg, __each_hub); +} +EXPORT_SYMBOL_GPL(usb_for_each_port); + /** * usb_release_dev - free a usb device structure when all users of it are finished. * @dev: device that's been disconnected @@ -748,6 +794,38 @@ void usb_put_intf(struct usb_interface *intf) } EXPORT_SYMBOL_GPL(usb_put_intf); +/** + * usb_intf_get_dma_device - acquire a reference on the usb interface's DMA endpoint + * @intf: the usb interface + * + * While a USB device cannot perform DMA operations by itself, many USB + * controllers can. A call to usb_intf_get_dma_device() returns the DMA endpoint + * for the given USB interface, if any. The returned device structure must be + * released with put_device(). + * + * See also usb_get_dma_device(). + * + * Returns: A reference to the usb interface's DMA endpoint; or NULL if none + * exists. + */ +struct device *usb_intf_get_dma_device(struct usb_interface *intf) +{ + struct usb_device *udev = interface_to_usbdev(intf); + struct device *dmadev; + + if (!udev->bus) + return NULL; + + dmadev = get_device(udev->bus->sysdev); + if (!dmadev || !dmadev->dma_mask) { + put_device(dmadev); + return NULL; + } + + return dmadev; +} +EXPORT_SYMBOL_GPL(usb_intf_get_dma_device); + /* USB device locking * * USB devices and interfaces are locked using the semaphore in their @@ -950,17 +1028,15 @@ static struct notifier_block usb_bus_nb = { .notifier_call = usb_bus_notify, }; -static struct dentry *usb_devices_root; - static void usb_debugfs_init(void) { - usb_devices_root = debugfs_create_file("devices", 0444, usb_debug_root, - NULL, &usbfs_devices_fops); + debugfs_create_file("devices", 0444, usb_debug_root, NULL, + &usbfs_devices_fops); } static void usb_debugfs_cleanup(void) { - debugfs_remove(usb_devices_root); + debugfs_remove(debugfs_lookup("devices", usb_debug_root)); } /* |