diff options
Diffstat (limited to 'include/linux/ntb.h')
| -rw-r--r-- | include/linux/ntb.h | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/include/linux/ntb.h b/include/linux/ntb.h index 8ff9d663096b..879c3e89e026 100644 --- a/include/linux/ntb.h +++ b/include/linux/ntb.h @@ -256,6 +256,7 @@ static inline int ntb_ctx_ops_is_valid(const struct ntb_ctx_ops *ops) * @msg_clear_mask: See ntb_msg_clear_mask(). * @msg_read: See ntb_msg_read(). * @peer_msg_write: See ntb_peer_msg_write(). + * @get_dma_dev: See ntb_get_dma_dev(). */ struct ntb_dev_ops { int (*port_number)(struct ntb_dev *ntb); @@ -329,6 +330,7 @@ struct ntb_dev_ops { int (*msg_clear_mask)(struct ntb_dev *ntb, u64 mask_bits); u32 (*msg_read)(struct ntb_dev *ntb, int *pidx, int midx); int (*peer_msg_write)(struct ntb_dev *ntb, int pidx, int midx, u32 msg); + struct device *(*get_dma_dev)(struct ntb_dev *ntb); }; static inline int ntb_dev_ops_is_valid(const struct ntb_dev_ops *ops) @@ -391,6 +393,8 @@ static inline int ntb_dev_ops_is_valid(const struct ntb_dev_ops *ops) /* !ops->msg_clear_mask == !ops->msg_count && */ !ops->msg_read == !ops->msg_count && !ops->peer_msg_write == !ops->msg_count && + + /* ops->get_dma_dev is optional */ 1; } @@ -1564,6 +1568,26 @@ static inline int ntb_peer_msg_write(struct ntb_dev *ntb, int pidx, int midx, } /** + * ntb_get_dma_dev() - get the device to use for DMA allocations/mappings + * @ntb: NTB device context. + * + * Return a struct device suitable for DMA API allocations and mappings. + * This is typically the parent of the NTB device, but may be overridden by a + * driver by implementing .get_dma_dev(). + * + * Drivers that implement .get_dma_dev() must return a non-NULL pointer. + * + * Return: device pointer to use for DMA operations. + */ +static inline struct device *ntb_get_dma_dev(struct ntb_dev *ntb) +{ + if (!ntb->ops->get_dma_dev) + return ntb->dev.parent; + + return ntb->ops->get_dma_dev(ntb); +} + +/** * ntb_peer_resource_idx() - get a resource index for a given peer idx * @ntb: NTB device context. * @pidx: Peer port index. |