On 25/01/21, Arnd Bergmann wrote:
> From: Arnd Bergmann <a...@arndb.de>
>
> 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: c05210ab9757 ("drivers: optee: allow op-tee to access devices on the
> i2c bus")
does fixing stack-frame compile warnings need a 'fixes' tag?
> Signed-off-by: Arnd Bergmann <a...@arndb.de>
> ---
> drivers/tee/optee/rpc.c | 31 ++++++++++++++++---------------
> 1 file changed, 16 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/tee/optee/rpc.c b/drivers/tee/optee/rpc.c
> index 1e3614e4798f..6cbb3643c6c4 100644
> --- a/drivers/tee/optee/rpc.c
> +++ b/drivers/tee/optee/rpc.c
> @@ -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:
> --
> 2.29.2
>
