diff --git a/src/providers/trusted_service/context/mod.rs b/src/providers/trusted_service/context/mod.rs
index 303d3df9..aa5ed498 100644
--- a/src/providers/trusted_service/context/mod.rs
+++ b/src/providers/trusted_service/context/mod.rs
@@ -4,7 +4,7 @@ use error::{Error, WrapperError};
 use log::{error, info, trace};
 use prost::Message;
 use std::convert::{TryFrom, TryInto};
-use std::ffi::{c_void, CString};
+use std::ffi::CString;
 use std::io::{self};
 use std::ptr::null_mut;
 use std::slice;
@@ -61,9 +61,8 @@ mod ts_protobuf;
 /// is required from the caller.
 #[derive(Debug)]
 pub struct Context {
-    rpc_caller: *mut rpc_caller,
+    rpc_caller_session: *mut rpc_caller_session,
     service_context: *mut service_context,
-    rpc_session_handle: *mut c_void,
     call_mutex: Mutex<()>,
 }
 
@@ -75,33 +74,20 @@ impl Context {
         unsafe { service_locator_init() };
 
         info!("Obtaining a crypto Trusted Service context.");
-        let mut status = 0;
         let service_name = CString::new("sn:trustedfirmware.org:crypto-protobuf:0").unwrap();
-        let service_context = unsafe { service_locator_query(service_name.as_ptr(), &mut status) };
+        let service_context = unsafe { service_locator_query(service_name.as_ptr()) };
         if service_context.is_null() {
-            error!("Locating crypto Trusted Service failed, status: {}", status);
+            error!("Locating crypto Trusted Service failed");
             return Err(io::Error::new(
                 io::ErrorKind::Other,
                 "Failed to obtain a Trusted Service context",
             )
             .into());
-        } else if status != 0 {
-            return Err(io::Error::new(
-                io::ErrorKind::Other,
-                format!(
-                    "Failed to connect to Trusted Service; status code: {}",
-                    status
-                ),
-            )
-            .into());
         }
 
         info!("Starting crypto Trusted Service context");
-        let mut rpc_caller = null_mut();
-        let rpc_session_handle = unsafe {
-            service_context_open(service_context, TS_RPC_ENCODING_PROTOBUF, &mut rpc_caller)
-        };
-        if rpc_caller.is_null() || rpc_session_handle.is_null() {
+        let rpc_caller_session = unsafe { service_context_open(service_context) };
+        if rpc_caller_session.is_null() {
             return Err(io::Error::new(
                 io::ErrorKind::Other,
                 "Failed to start Trusted Service context",
@@ -109,9 +95,8 @@ impl Context {
             .into());
         }
         let ctx = Context {
-            rpc_caller,
+            rpc_caller_session,
             service_context,
-            rpc_session_handle,
             call_mutex: Mutex::new(()),
         };
 
@@ -129,8 +114,19 @@ impl Context {
         trace!("Beginning call to Trusted Service");
 
         let mut buf_out = null_mut();
-        let call_handle =
-            unsafe { rpc_caller_begin(self.rpc_caller, &mut buf_out, req.encoded_len()) };
+        // The response buffer length is set to 4096 as a common buffer length
+        // for all operations. In case of the session memory policy being "alloc_for_session"
+        // which is dependant on the platform, this value doesnt impact but for
+        // platforms with memory policy "alloc_for_each_call" the buffer length should be
+        // sufficient enough to hold the entire response.
+        let call_handle = unsafe {
+            rpc_caller_session_begin(
+                self.rpc_caller_session,
+                &mut buf_out,
+                req.encoded_len(),
+                4096,
+            )
+        };
         if call_handle.is_null() {
             error!("Call handle was null");
             return Err(WrapperError::CallHandleNull.into());
@@ -140,7 +136,9 @@ impl Context {
         }
         let mut buf_out = unsafe { slice::from_raw_parts_mut(buf_out, req.encoded_len()) };
         req.encode(&mut buf_out).map_err(|e| {
-            unsafe { rpc_caller_end(self.rpc_caller, call_handle) };
+            unsafe {
+                let _ = rpc_caller_session_end(call_handle);
+            };
             format_error!("Failed to serialize Protobuf request", e);
             WrapperError::FailedPbConversion
         })?;
@@ -151,13 +149,12 @@ impl Context {
         let mut resp_buf = null_mut();
         let mut resp_buf_size = 0;
         let status = unsafe {
-            rpc_caller_invoke(
-                self.rpc_caller,
+            rpc_caller_session_invoke(
                 call_handle,
                 i32::from(req.opcode()).try_into().unwrap(),
-                &mut opstatus,
                 &mut resp_buf,
                 &mut resp_buf_size,
+                &mut opstatus,
             )
         };
         Error::from_status_opstatus(
@@ -165,16 +162,23 @@ impl Context {
             i32::try_from(opstatus).map_err(|_| Error::Wrapper(WrapperError::InvalidOpStatus))?,
         )
         .map_err(|e| {
-            unsafe { rpc_caller_end(self.rpc_caller, call_handle) };
+            unsafe {
+                let _ = rpc_caller_session_end(call_handle);
+            };
             e
         })?;
         let resp_buf = unsafe { slice::from_raw_parts_mut(resp_buf, resp_buf_size) };
         resp.merge(&*resp_buf).map_err(|e| {
-            unsafe { rpc_caller_end(self.rpc_caller, call_handle) };
+            unsafe {
+                let _ = rpc_caller_session_end(call_handle);
+            };
             format_error!("Failed to serialize Protobuf request", e);
             WrapperError::FailedPbConversion
         })?;
-        unsafe { rpc_caller_end(self.rpc_caller, call_handle) };
+        unsafe {
+            let status = rpc_caller_session_end(call_handle);
+            Error::from_status_opstatus(status, 0)?;
+        };
 
         Ok(resp)
     }
@@ -182,7 +186,7 @@ impl Context {
 
 impl Drop for Context {
     fn drop(&mut self) {
-        unsafe { service_context_close(self.service_context, self.rpc_session_handle) };
+        unsafe { service_context_close(self.service_context, self.rpc_caller_session) };
 
         unsafe { service_context_relinquish(self.service_context) };
     }