[PATCH 3/9] bus: mhi: ep: Introduce async read/write callbacks

[Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>]

These callbacks can be implemented by the controller drivers to perform
async read/write operation that increases the throughput.

For aiding the async operation, a completion callback is also introduced.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
---
 include/linux/mhi_ep.h | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/include/linux/mhi_ep.h b/include/linux/mhi_ep.h
index b96b543bf2f6..14c6e8d3f573 100644
--- a/include/linux/mhi_ep.h
+++ b/include/linux/mhi_ep.h
@@ -54,11 +54,16 @@ struct mhi_ep_db_info {
  * @dev_addr: Address of the buffer in endpoint
  * @host_addr: Address of the bufffer in host
  * @size: Size of the buffer
+ * @cb: Callback to be executed by controller drivers after transfer completion (async)
+ * @cb_buf: Opaque buffer to be passed to the callback
  */
 struct mhi_ep_buf_info {
 	void *dev_addr;
 	u64 host_addr;
 	size_t size;
+
+	void (*cb)(struct mhi_ep_buf_info *buf_info);
+	void *cb_buf;
 };
 
 /**
@@ -96,6 +101,8 @@ struct mhi_ep_buf_info {
  * @unmap_free: CB function to unmap and free the allocated memory in endpoint for storing host context
  * @read_sync: CB function for reading from host memory synchronously
  * @write_sync: CB function for writing to host memory synchronously
+ * @read_async: CB function for reading from host memory asynchronously
+ * @write_async: CB function for writing to host memory asynchronously
  * @mhi_state: MHI Endpoint state
  * @max_chan: Maximum channels supported by the endpoint controller
  * @mru: MRU (Maximum Receive Unit) value of the endpoint controller
@@ -151,6 +158,8 @@ struct mhi_ep_cntrl {
 			   void __iomem *virt, size_t size);
 	int (*read_sync)(struct mhi_ep_cntrl *mhi_cntrl, struct mhi_ep_buf_info *buf_info);
 	int (*write_sync)(struct mhi_ep_cntrl *mhi_cntrl, struct mhi_ep_buf_info *buf_info);
+	int (*read_async)(struct mhi_ep_cntrl *mhi_cntrl, struct mhi_ep_buf_info *buf_info);
+	int (*write_async)(struct mhi_ep_cntrl *mhi_cntrl, struct mhi_ep_buf_info *buf_info);
 
 	enum mhi_state mhi_state;
 
-- 
2.25.1