optee: refactor driver with internal callbacks

The OP-TEE driver is refactored with three internal callbacks replacing
direct calls to optee_from_msg_param(), optee_to_msg_param() and
optee_do_call_with_arg().

These functions a central to communicating with OP-TEE in secure world
by using the SMC Calling Convention directly.

This refactoring makes room for using other primitives to communicate
with OP-TEE in secure world while being able to reuse as much as
possible from the present driver.

Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

1 files changed, 12 insertions, 7 deletions

diff --git a/drivers/tee/optee/rpc.c b/drivers/tee/optee/rpc.c
index efbaff7ad7e5..309258d47790 100644
--- a/drivers/tee/optee/rpc.c
+++ b/drivers/tee/optee/rpc.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
- * Copyright (c) 2015-2016, Linaro Limited
+ * Copyright (c) 2015-2021, Linaro Limited
  */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
@@ -55,6 +55,7 @@ bad:
 static void handle_rpc_func_cmd_i2c_transfer(struct tee_context *ctx,
 					     struct optee_msg_arg *arg)
 {
+	struct optee *optee = tee_get_drvdata(ctx->teedev);
 	struct tee_param *params;
 	struct i2c_adapter *adapter;
 	struct i2c_msg msg = { };
@@ -79,7 +80,8 @@ static void handle_rpc_func_cmd_i2c_transfer(struct tee_context *ctx,
 		return;
 	}
 
-	if (optee_from_msg_param(params, arg->num_params, arg->params))
+	if (optee->ops->from_msg_param(optee, params, arg->num_params,
+				       arg->params))
 		goto bad;
 
 	for (i = 0; i < arg->num_params; i++) {
@@ -122,7 +124,8 @@ static void handle_rpc_func_cmd_i2c_transfer(struct tee_context *ctx,
 		arg->ret = TEEC_ERROR_COMMUNICATION;
 	} else {
 		params[3].u.value.a = msg.len;
-		if (optee_to_msg_param(arg->params, arg->num_params, params))
+		if (optee->ops->to_msg_param(optee, arg->params,
+					     arg->num_params, params))
 			arg->ret = TEEC_ERROR_BAD_PARAMETERS;
 		else
 			arg->ret = TEEC_SUCCESS;
@@ -234,7 +237,7 @@ bad:
 	arg->ret = TEEC_ERROR_BAD_PARAMETERS;
 }
 
-static void handle_rpc_supp_cmd(struct tee_context *ctx,
+static void handle_rpc_supp_cmd(struct tee_context *ctx, struct optee *optee,
 				struct optee_msg_arg *arg)
 {
 	struct tee_param *params;
@@ -248,14 +251,16 @@ static void handle_rpc_supp_cmd(struct tee_context *ctx,
 		return;
 	}
 
-	if (optee_from_msg_param(params, arg->num_params, arg->params)) {
+	if (optee->ops->from_msg_param(optee, params, arg->num_params,
+				       arg->params)) {
 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
 		goto out;
 	}
 
 	arg->ret = optee_supp_thrd_req(ctx, arg->cmd, arg->num_params, params);
 
-	if (optee_to_msg_param(arg->params, arg->num_params, params))
+	if (optee->ops->to_msg_param(optee, arg->params, arg->num_params,
+				     params))
 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
 out:
 	kfree(params);
@@ -480,7 +485,7 @@ static void handle_rpc_func_cmd(struct tee_context *ctx, struct optee *optee,
 		handle_rpc_func_cmd_i2c_transfer(ctx, arg);
 		break;
 	default:
-		handle_rpc_supp_cmd(ctx, arg);
+		handle_rpc_supp_cmd(ctx, optee, arg);
 	}
 }