diff options
| -rw-r--r-- | drivers/usb/host/dwc_otg/dwc_otg_hcd_linux.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/drivers/usb/host/dwc_otg/dwc_otg_hcd_linux.c b/drivers/usb/host/dwc_otg/dwc_otg_hcd_linux.c index 1d28459d5b0e..6aad9c437998 100644 --- a/drivers/usb/host/dwc_otg/dwc_otg_hcd_linux.c +++ b/drivers/usb/host/dwc_otg/dwc_otg_hcd_linux.c @@ -766,16 +766,17 @@ static int dwc_otg_urb_enqueue(struct usb_hcd *hcd, !(usb_pipein(urb->pipe)))); buf = urb->transfer_buffer; - if (hcd->self.uses_dma) { + if (hcd->self.uses_dma && !buf && urb->transfer_buffer_length) { /* * Calculate virtual address from physical address, * because some class driver may not fill transfer_buffer. * In Buffer DMA mode virual address is used, * when handling non DWORD aligned buffers. */ - //buf = phys_to_virt(urb->transfer_dma); - // DMA addresses are bus addresses not physical addresses! - buf = dma_to_virt(&urb->dev->dev, urb->transfer_dma); + buf = (void *)__bus_to_virt((unsigned long)urb->transfer_dma); + dev_warn_once(&urb->dev->dev, + "USB transfer_buffer was NULL, will use __bus_to_virt(%pad)=%p\n", + &urb->transfer_dma, buf); } if (!(urb->transfer_flags & URB_NO_INTERRUPT)) |