diff options
Diffstat (limited to 'drivers/usb/core/usb.c')
| -rw-r--r-- | drivers/usb/core/usb.c | 60 |
1 files changed, 37 insertions, 23 deletions
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c index 7dad603..0a6ee2e 100644 --- a/drivers/usb/core/usb.c +++ b/drivers/usb/core/usb.c @@ -68,6 +68,8 @@ MODULE_PARM_DESC(autosuspend, "default autosuspend delay"); * @alt_num: alternate interface setting number to search for. * * Search the configuration's interface cache for the given alt setting. + * + * Return: The alternate setting, if found. %NULL otherwise. */ struct usb_host_interface *usb_find_alt_setting( struct usb_host_config *config, @@ -103,8 +105,7 @@ EXPORT_SYMBOL_GPL(usb_find_alt_setting); * @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. + * to find the interface object with the particular interface number. * * Note that configuration descriptors are not required to assign interface * numbers sequentially, so that it would be incorrect to assume that @@ -115,6 +116,9 @@ EXPORT_SYMBOL_GPL(usb_find_alt_setting); * * Don't call this function unless you are bound to one of the interfaces * on this device or you have locked the device! + * + * Return: A pointer to the interface that has @ifnum as interface number, + * if found. %NULL otherwise. */ struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev, unsigned ifnum) @@ -139,8 +143,7 @@ EXPORT_SYMBOL_GPL(usb_ifnum_to_if); * @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. + * an entry with the correct bAlternateSetting value. * * Note that altsettings need not be stored sequentially by number, so * it would be incorrect to assume that the first altsetting entry in @@ -149,6 +152,9 @@ EXPORT_SYMBOL_GPL(usb_ifnum_to_if); * * Don't call this function unless you are bound to the intf interface * or you have locked the device! + * + * Return: A pointer to the entry of the altsetting array of @intf that + * has @altnum as the alternate setting number. %NULL if not found. */ struct usb_host_interface *usb_altnum_to_altsetting( const struct usb_interface *intf, @@ -191,6 +197,8 @@ static int __find_interface(struct device *dev, void *data) * 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. + * + * Return: A pointer to the interface with the matching major and @minor. */ struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor) { @@ -390,6 +398,9 @@ static unsigned usb_bus_is_wusb(struct usb_bus *bus) * controllers) should ever call this. * * This call may not be used in a non-sleeping context. + * + * Return: On success, a pointer to the allocated usb device. %NULL on + * failure. */ struct usb_device *usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus, unsigned port1) @@ -501,7 +512,7 @@ struct usb_device *usb_alloc_dev(struct usb_device *parent, * 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. + * Return: A pointer to the device with the incremented reference counter. */ struct usb_device *usb_get_dev(struct usb_device *dev) { @@ -535,8 +546,7 @@ EXPORT_SYMBOL_GPL(usb_put_dev); * 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. + * Return: A pointer to the interface with the incremented reference counter. */ struct usb_interface *usb_get_intf(struct usb_interface *intf) { @@ -589,7 +599,7 @@ EXPORT_SYMBOL_GPL(usb_put_intf); * 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. + * Return: A negative error code for failure, otherwise 0. */ int usb_lock_device_for_reset(struct usb_device *udev, const struct usb_interface *iface) @@ -628,14 +638,15 @@ 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 + * Return: 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. + * Note: 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) { @@ -685,11 +696,12 @@ EXPORT_SYMBOL_GPL(__usb_get_extra_descriptor); * @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 + * Return: 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). * + * Note: * 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 @@ -735,17 +747,18 @@ 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. + * 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(). + * + * Return: Either %NULL (indicating no buffer could be mapped), or @urb. + * */ #if 0 struct urb *usb_buffer_map(struct urb *urb) @@ -850,9 +863,10 @@ EXPORT_SYMBOL_GPL(usb_buffer_unmap); * @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. + * Return: Either < 0 (indicating no buffers could be mapped), or the + * number of DMA mapping array entries in the scatterlist. * + * Note: * 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. |