[PATCH v4 0/3] mmc: sdhci: Set DMA mask properly

[Alexandre Courbot <acourbot@nvidia.com>]

64-bit capable devices are supposed to set their own DMA mask. Currently
this does not happen for sdhci devices excepted for the two (sdhci-acpi
and sdhci-pci) that define a enable_dma() hook and do it there. However
this hook is called from several places while DMA mask is supposed to
be set only once ; for instance the sdhci-acpi driver maintains a flag
just to make sure the DMA mask is set only upon the first call of this
hook.

For the vast majority of drivers that do not define a enable_dma() hook, the
default 32-bit DMA mask is used and there is a risk of using unneeded bounce
buffers on hosts capable of 64-bit addressing.

The first patch adds a default DMA mask setting function that is called when
a DMA-capable host is added. It tries to set sane DMA masks according to the
device's reported capabilities.

The addition of this function seems to make the same code in sdhci-acpi and
sdhci-pci redundant, so it is removed from these drivers. On top of making
this series a negative line count, it also removes one usage of the obsolete
pci_set_dma_mask() function.

Changes since v3:
- Unset the SDHCI_USE_64_BIT_DMA flag if setting of 64-bit mask failed
- Carry Acked-bys

Alexandre Courbot (3):
  mmc: sdhci: Set DMA mask when adding host
  mmc: sdhci-acpi: Remove enable_dma() hook
  mmc: sdhci-pci: Do not set DMA mask in enable_dma()

 drivers/mmc/host/sdhci-acpi.c     | 30 ------------------------
 drivers/mmc/host/sdhci-pci-core.c | 15 ------------
 drivers/mmc/host/sdhci.c          | 48 +++++++++++++++++++++++++++++++++------
 3 files changed, 41 insertions(+), 52 deletions(-)

-- 
2.7.2