diff options
| author | Duc Dang <dhdang@apm.com> | 2015-10-09 13:30:11 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-10-17 09:34:22 +0300 |
| commit | 0ebbe398f68be0d9bbd41dcfb57319e697756b37 (patch) | |
| tree | 3a212cfa00f80aff88db6ef423b3a2a18cad0481 /drivers/usb/host | |
| parent | 8451a34ff6c7c756e9e0f0094a3ba856c9734e5d (diff) | |
| download | linux-0ebbe398f68be0d9bbd41dcfb57319e697756b37.tar.xz | |
usb: make xhci platform driver use 64 bit or 32 bit DMA
The xhci platform driver needs to work on systems that
either only support 64-bit DMA or only support 32-bit DMA.
Attempt to set a coherent dma mask for 64-bit DMA, and
attempt again with 32-bit DMA if that fails.
[dhdang: regenerate the patch over v4.3-rc1 and address new comments]
Signed-off-by: Mark Langsdorf <mlangsdo@redhat.com>
Tested-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Duc Dang <dhdang@apm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/host')
| -rw-r--r-- | drivers/usb/host/xhci-plat.c | 20 |
1 files changed, 13 insertions, 7 deletions
diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c index 890ad9d9d329..34c93e87b2d3 100644 --- a/drivers/usb/host/xhci-plat.c +++ b/drivers/usb/host/xhci-plat.c @@ -93,14 +93,20 @@ static int xhci_plat_probe(struct platform_device *pdev) if (irq < 0) return -ENODEV; - /* Initialize dma_mask and coherent_dma_mask to 32-bits */ - ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32)); - if (ret) - return ret; - if (!pdev->dev.dma_mask) - pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask; + /* Try to set 64-bit DMA first */ + if (WARN_ON(!pdev->dev.dma_mask)) + /* Platform did not initialize dma_mask */ + ret = dma_coerce_mask_and_coherent(&pdev->dev, + DMA_BIT_MASK(64)); else - dma_set_mask(&pdev->dev, DMA_BIT_MASK(32)); + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); + + /* If seting 64-bit DMA mask fails, fall back to 32-bit DMA mask */ + if (ret) { + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); + if (ret) + return ret; + } hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev)); if (!hcd) |