[RFC PATCH v4 15/38] PCI: endpoint: pci-epf-vntb: Implement .get_dma_dev()

[Koichiro Den]

For DMA API allocations and mappings, pci-epf-vntb should provide an
appropriate struct device for the NTB core/clients.

Implement .get_dma_dev() and return the EPC parent device.

Signed-off-by: Koichiro Den <den@xxxxxxxxxxxxx>
---
 drivers/pci/endpoint/functions/pci-epf-vntb.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c
index 9fbc27000f77..7cd976757d15 100644
--- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
@@ -1747,6 +1747,15 @@ static int vntb_epf_link_disable(struct ntb_dev *ntb)
 	return 0;
 }
 
+static struct device *vntb_epf_get_dma_dev(struct ntb_dev *ndev)
+{
+	struct epf_ntb *ntb = ntb_ndev(ndev);
+
+	if (!ntb || !ntb->epf)
+		return NULL;
+	return ntb->epf->epc->dev.parent;
+}
+
 static void *vntb_epf_get_private_data(struct ntb_dev *ndev)
 {
 	struct epf_ntb *ntb = ntb_ndev(ndev);
@@ -1780,6 +1789,7 @@ static const struct ntb_dev_ops vntb_epf_ops = {
 	.db_clear_mask		= vntb_epf_db_clear_mask,
 	.db_clear		= vntb_epf_db_clear,
 	.link_disable		= vntb_epf_link_disable,
+	.get_dma_dev		= vntb_epf_get_dma_dev,
 	.get_private_data	= vntb_epf_get_private_data,
 };
 
-- 
2.51.0