Commit 67bc8097 authored by Arnd Bergmann's avatar Arnd Bergmann Committed by Jens Wiklander
Browse files

optee: simplify i2c access 



Storing a bogus i2c_client structure on the stack adds overhead and
causes a compile-time warning:

drivers/tee/optee/rpc.c:493:6: error: stack frame size of 1056 bytes in function 'optee_handle_rpc' [-Werror,-Wframe-larger-than=]
void optee_handle_rpc(struct tee_context *ctx, struct optee_rpc_param *param,

Change the implementation of handle_rpc_func_cmd_i2c_transfer() to
open-code the i2c_transfer() call, which makes it easier to read
and avoids the warning.

Fixes: c05210ab ("drivers: optee: allow op-tee to access devices on the i2c bus")
Tested-by: default avatarJorge Ramirez-Ortiz <jorge@foundries.io>
Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarJens Wiklander <jens.wiklander@linaro.org>
parent e71ba945

drivers/tee/optee/rpc.c

+16 −15
Original line number Diff line number Diff line
@@ -54,8 +54,9 @@ static void handle_rpc_func_cmd_get_time(struct optee_msg_arg *arg) 
static void handle_rpc_func_cmd_i2c_transfer(struct tee_context *ctx,

					     struct optee_msg_arg *arg)

{

	struct i2c_client client = { 0 };

	struct tee_param *params;

	struct i2c_adapter *adapter;

	struct i2c_msg msg = { };

	size_t i;

	int ret = -EOPNOTSUPP;

	u8 attr[] = {
@@ -85,48 +86,48 @@ static void handle_rpc_func_cmd_i2c_transfer(struct tee_context *ctx, 
			goto bad;

	}



	client.adapter = i2c_get_adapter(params[0].u.value.b);

	if (!client.adapter)

	adapter = i2c_get_adapter(params[0].u.value.b);

	if (!adapter)

		goto bad;



	if (params[1].u.value.a & OPTEE_MSG_RPC_CMD_I2C_FLAGS_TEN_BIT) {

		if (!i2c_check_functionality(client.adapter,

		if (!i2c_check_functionality(adapter,

					     I2C_FUNC_10BIT_ADDR)) {

			i2c_put_adapter(client.adapter);

			i2c_put_adapter(adapter);

			goto bad;

		}



		client.flags = I2C_CLIENT_TEN;

		msg.flags = I2C_M_TEN;

	}



	client.addr = params[0].u.value.c;

	snprintf(client.name, I2C_NAME_SIZE, "i2c%d", client.adapter->nr);

	msg.addr = params[0].u.value.c;

	msg.buf  = params[2].u.memref.shm->kaddr;

	msg.len  = params[2].u.memref.size;



	switch (params[0].u.value.a) {

	case OPTEE_MSG_RPC_CMD_I2C_TRANSFER_RD:

		ret = i2c_master_recv(&client, params[2].u.memref.shm->kaddr,

				      params[2].u.memref.size);

		msg.flags |= I2C_M_RD;

		break;

	case OPTEE_MSG_RPC_CMD_I2C_TRANSFER_WR:

		ret = i2c_master_send(&client, params[2].u.memref.shm->kaddr,

				      params[2].u.memref.size);

		break;

	default:

		i2c_put_adapter(client.adapter);

		i2c_put_adapter(adapter);

		goto bad;

	}



	ret = i2c_transfer(adapter, &msg, 1);



	if (ret < 0) {

		arg->ret = TEEC_ERROR_COMMUNICATION;

	} else {

		params[3].u.value.a = ret;

		params[3].u.value.a = msg.len;

		if (optee_to_msg_param(arg->params, arg->num_params, params))

			arg->ret = TEEC_ERROR_BAD_PARAMETERS;

		else

			arg->ret = TEEC_SUCCESS;

	}



	i2c_put_adapter(client.adapter);

	i2c_put_adapter(adapter);

	kfree(params);

	return;

bad: