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| author | Andrey Smirnov <andrew.smirnov@gmail.com> | 2019-02-19 23:29:12 -0800 |
|---|---|---|
| committer | Sascha Hauer <s.hauer@pengutronix.de> | 2019-02-22 08:11:18 +0100 |
| commit | 882e9108bb09eb1fb4287f0b2241675eecac9db4 (patch) | |
| tree | 97d2ec7befcedab81d74ddbcfccbbaa404e4cc8b /drivers | |
| parent | e77f11086a5616adfafa6c4c784c4be969eb8570 (diff) | |
| download | barebox-882e9108bb09eb1fb4287f0b2241675eecac9db4.tar.gz barebox-882e9108bb09eb1fb4287f0b2241675eecac9db4.tar.xz | |
usb: xhci-hcd: Don't try to DMA sync if buffer is NULL
Driver's .submit_control() callback can and will be called with buffer
set to NULL (and length set to 0), so we need to make sure that we
don't try to DMA sync the buffer in that case. Add appropriate gurads
to make sure that doesn't happen.
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/usb/host/xhci-hcd.c | 21 |
1 files changed, 13 insertions, 8 deletions
diff --git a/drivers/usb/host/xhci-hcd.c b/drivers/usb/host/xhci-hcd.c index 855dc47c52..8a00b8854c 100644 --- a/drivers/usb/host/xhci-hcd.c +++ b/drivers/usb/host/xhci-hcd.c @@ -1200,10 +1200,12 @@ static int xhci_submit_control(struct usb_device *udev, unsigned long pipe, return ret; } - /* Pass ownership of data buffer to device */ - dma_sync_single_for_device((unsigned long)buffer, length, - (req->requesttype & USB_DIR_IN) ? - DMA_FROM_DEVICE : DMA_TO_DEVICE); + if (length > 0) { + /* Pass ownership of data buffer to device */ + dma_sync_single_for_device((unsigned long)buffer, length, + (req->requesttype & USB_DIR_IN) ? + DMA_FROM_DEVICE : DMA_TO_DEVICE); + } /* Setup TRB */ memset(&trb, 0, sizeof(union xhci_trb)); @@ -1259,10 +1261,13 @@ static int xhci_submit_control(struct usb_device *udev, unsigned long pipe, xhci_print_trb(xhci, &trb, "Response Status"); dma_regain: - /* Regain ownership of data buffer from device */ - dma_sync_single_for_cpu((unsigned long)buffer, length, - (req->requesttype & USB_DIR_IN) ? - DMA_FROM_DEVICE : DMA_TO_DEVICE); + if (length > 0) { + /* Regain ownership of data buffer from device */ + dma_sync_single_for_cpu((unsigned long)buffer, length, + (req->requesttype & USB_DIR_IN) ? + DMA_FROM_DEVICE : DMA_TO_DEVICE); + } + if (ret < 0) return ret; |