dmaengine: idma64: Use actual device for DMA transfers
authorAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Mon, 18 Mar 2019 15:39:30 +0000 (18:39 +0300)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 15 Jun 2019 09:54:10 +0000 (11:54 +0200)
commit9fdcb04e80e1d7a92c7eb23bc0ba1243bc30ddfd
tree86627d5a3c8a20a44217ff363729478bffdb8c19
parentda00c89fce7a04875d1ebdf3c9115226854ff0e6
dmaengine: idma64: Use actual device for DMA transfers

[ Upstream commit 5ba846b1ee0792f5a596b9b0b86d6e8cdebfab06 ]

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: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [for tty parts]
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/dma/idma64.c
drivers/dma/idma64.h
drivers/spi/spi-pxa2xx.c
drivers/tty/serial/8250/8250_dw.c