diff options
| author | Noralf Trønnes <noralf@tronnes.org> | 2015-05-15 20:20:09 +0200 |
|---|---|---|
| committer | popcornmix <popcornmix@gmail.com> | 2015-05-18 14:13:31 +0100 |
| commit | d54112e7c36831a5c1033135f10b4c228e6165fa (patch) | |
| tree | 78290ca3a6212d535fe4028a41cc1e40483a5f1e | |
| parent | 8beaa1d2022374c0ece1195aa155a1af52ca31e6 (diff) | |
| download | linux-d54112e7c36831a5c1033135f10b4c228e6165fa.tar.gz | |
usb: dwc_otg: Don't use dma_to_virt()
Commit 6ce0d20 changes dma_to_virt() which breaks this driver.
Open code the old dma_to_virt() implementation to work around this.
Limit the use of __bus_to_virt() to cases where transfer_buffer_length
is set and transfer_buffer is not set. This is done to increase the
chance that this driver will also work on ARCH_BCM2835.
transfer_buffer should not be NULL if the length is set, but the
comment in the code indicates that there are situations where this
might happen. drivers/usb/isp1760/isp1760-hcd.c also has a similar
comment pointing to a possible: 'usb storage / SCSI bug'.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
| -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)) |