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>
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index b9a1311..ba8c6b4 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -16,6 +16,8 @@
#include <linux/pm_runtime.h>
#include <linux/suspend.h>
#include <linux/kexec.h>
+#include <linux/of_device.h>
+#include <linux/acpi.h>
#include "pci.h"
#include "pcie/portdrv.h"
@@ -1577,6 +1579,35 @@ static int pci_bus_num_vf(struct device *dev)
return pci_num_vf(to_pci_dev(dev));
}
+/**
+ * pci_dma_configure - Setup DMA configuration
+ * @dev: ptr to dev structure
+ *
+ * Function to update PCI devices's DMA configuration using the same
+ * info from the OF node or ACPI node of host bridge's parent (if any).
+ */
+static int pci_dma_configure(struct device *dev)
+{
+ struct device *bridge;
+ int ret = 0;
+
+ bridge = pci_get_host_bridge_device(to_pci_dev(dev));
+
+ if (IS_ENABLED(CONFIG_OF) && bridge->parent &&
+ bridge->parent->of_node) {
+ ret = of_dma_configure(dev, bridge->parent->of_node);
+ } else if (has_acpi_companion(bridge)) {
+ struct acpi_device *adev = to_acpi_device_node(bridge->fwnode);
+ enum dev_dma_attr attr = acpi_get_dma_attr(adev);
+
+ if (attr != DEV_DMA_NOT_SUPPORTED)
+ ret = acpi_dma_configure(dev, attr);
+ }
+
+ pci_put_host_bridge_device(bridge);
+ return ret;
+}
+
struct bus_type pci_bus_type = {
.name = "pci",
.match = pci_bus_match,
@@ -1589,6 +1620,7 @@ struct bus_type pci_bus_type = {
.drv_groups = pci_drv_groups,
.pm = PCI_PM_OPS_PTR,
.num_vf = pci_bus_num_vf,
+ .dma_configure = pci_dma_configure,
.force_dma = true,
};
EXPORT_SYMBOL(pci_bus_type);