1. 11 Dec, 2013 33 commits
  2. 10 Dec, 2013 2 commits
    • Stephen Warren's avatar
      dma: add dma_get_any_slave_channel(), for use in of_xlate() · 8010dad5
      Stephen Warren authored
      mmp_pdma.c implements a custom of_xlate() function that is 95% identical
      to what Tegra will need. Create a function to implement the common part,
      so everyone doesn't just cut/paste the implementation.
      
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Vinod Koul <vinod.koul@intel.com>
      Cc: Lars-Peter Clausen <lars@metafoo.de>
      Cc: dmaengine@vger.kernel.org
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarStephen Warren <swarren@nvidia.com>
      Signed-off-by: default avatarVinod Koul <vinod.koul@intel.com>
      8010dad5
    • Stephen Warren's avatar
      dma: add channel request API that supports deferred probe · 0ad7c000
      Stephen Warren authored
      dma_request_slave_channel() simply returns NULL whenever DMA channel
      lookup fails. Lookup could fail for two distinct reasons:
      
      a) No DMA specification exists for the channel name.
         This includes situations where no DMA specifications exist at all, or
         other general lookup problems.
      
      b) A DMA specification does exist, yet the driver for that channel is not
         yet registered.
      
      Case (b) should trigger deferred probe in client drivers. However, since
      they have no way to differentiate the two situations, it cannot.
      
      Implement new function dma_request_slave_channel_reason(), which performs
      identically to dma_request_slave_channel(), except that it returns an
      error-pointer rather than NULL, which allows callers to detect when
      deferred probe should occur.
      
      Eventually, all drivers should be converted to this new API, the old API
      removed, and the new API renamed to the more desirable name. This patch
      doesn't convert the existing API and all drivers in one go, since some
      drivers call dma_request_slave_channel() then dma_request_channel() if
      that fails. That would require either modifying dma_request_channel() in
      the same way, or adding extra error-handling code to all affected
      drivers, and there are close to 100 drivers using the other API, rather
      than just the 15-20 or so that use dma_request_slave_channel(), which
      might be tenable in a single patch.
      
      acpi_dma_request_slave_chan_by_name() doesn't currently implement
      deferred probe. It should, but this will be addressed later.
      Acked-by: default avatarDan Williams <dan.j.williams@intel.com>
      Signed-off-by: default avatarStephen Warren <swarren@nvidia.com>
      Signed-off-by: default avatarVinod Koul <vinod.koul@intel.com>
      0ad7c000
  3. 09 Dec, 2013 4 commits
  4. 06 Dec, 2013 1 commit