diff options
author | Borislav Petkov <bp@suse.de> | 2021-03-18 18:43:11 +0300 |
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committer | Borislav Petkov <bp@suse.de> | 2021-03-18 18:43:11 +0300 |
commit | afb4a37778491eae010a43edebea32ff2d45f01c (patch) | |
tree | c40bcc6143e5542134477dd96a108d24b1f9074f /drivers/usb/core/usb.c | |
parent | 229164175ff0c61ff581e6bf37fbfcb608b6e9bb (diff) | |
parent | 1e28eed17697bcf343c6743f0028cc3b5dd88bf0 (diff) | |
download | linux-afb4a37778491eae010a43edebea32ff2d45f01c.tar.xz |
Merge tag 'v5.12-rc3' into x86/seves
Pick up dependent SEV-ES urgent changes which went into -rc3 to base new
work ontop.
Signed-off-by: Borislav Petkov <bp@suse.de>
Diffstat (limited to 'drivers/usb/core/usb.c')
-rw-r--r-- | drivers/usb/core/usb.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c index 8f07b0516100..a566bb494e24 100644 --- a/drivers/usb/core/usb.c +++ b/drivers/usb/core/usb.c @@ -748,6 +748,38 @@ 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 |