dma-mapping: move dma configuration to bus infrastructure

ACPI/OF support for configuration of DMA is a bus specific aspect, and
thus should be configured by the bus.  Introduces a 'dma_configure' bus
method so that busses can control their DMA capabilities.

Also update the PCI, Platform, ACPI and host1x buses to use the new
method.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nipun Gupta <nipun.gupta@nxp.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>  # PCI parts
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[hch: simplified host1x_dma_configure based on a comment from Thierry,
      rewrote changelog]
Signed-off-by: Christoph Hellwig <hch@lst.de>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/device.h b/include/linux/device.h
index 477956990f5e..63aa672bd394 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -88,6 +88,8 @@ extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
  * @resume:     Called to bring a device on this bus out of sleep mode.
  * @num_vf:     Called to find out how many virtual functions a device on this
  *              bus supports.
+ * @dma_configure:      Called to setup DMA configuration on a device on
+                        this bus.
  * @pm:         Power management operations of this bus, callback the specific
  *              device driver's pm-ops.
  * @iommu_ops:  IOMMU specific operations for this bus, used to attach IOMMU
@@ -130,6 +132,8 @@ struct bus_type {
 
         int (*num_vf)(struct device *dev);
 
+        int (*dma_configure)(struct device *dev);
+
         const struct dev_pm_ops *pm;
 
         const struct iommu_ops *iommu_ops;