• Andy Shevchenko's avatar
    dmaengine: idma64: Use actual device for DMA transfers · 754b995f
    Andy Shevchenko authored
    [ Upstream commit 5ba846b1 ]
    
    Intel IOMMU, when enabled, tries to find the domain of the device,
    assuming it's a PCI one, during DMA operations, such as mapping or
    unmapping. Since we are splitting the actual PCI device to couple of
    children via MFD framework (see drivers/mfd/intel-lpss.c for details),
    the DMA device appears to be a platform one, and thus not an actual one
    that performs DMA. In a such situation IOMMU can't find or allocate
    a proper domain for its operations. As a result, all DMA operations are
    failed.
    
    In order to fix this, supply parent of the platform device
    to the DMA engine framework and fix filter functions accordingly.
    
    We may rely on the fact that parent is a real PCI device, because no
    other configuration is present in the wild.
    Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
    Acked-by: default avatarMark Brown <broonie@kernel.org>
    Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [for tty parts]
    Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
    Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
    754b995f
idma64.c 17.8 KB