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

Frank Li
2026-01-19T20:30:34Z

On Sun, Jan 18, 2026 at 10:54:17PM +0900, Koichiro Den wrote:
> 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.

Simple said:

Implement .get_dma_dev() and return the EPC parent device for NTB
core/client's DMA allocations and mappings API.

Reviewed-by: Frank Li <Frank.Li@nxp.com>
>
> Signed-off-by: Koichiro Den <den@valinux.co.jp>
> ---
> 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
>