A system on chip, SOC, comprising a bus interface, a secure element (120, 320, 420, 620), SE, and a first element (130, 330, 430, 630) that are integrated in the SOC, wherein the bus interface is configured to be connected to an input/output, I/O, device (350, 450, 650, 710) and to the SE; the SE is configured to: determine whether an application that currently requires the I/O device to input data is an application in the SE; when a secure scenario is determined based on a fact that the application currently requiring input is an application in the SE, access the I/O device by using the bus interface, obtain first data input by the I/O device without sending the first data to the first element, and perform secure processing on the first data; and when a common scenario is determined based on a fact that the application currently requiring input is not an application in the SE access the I/O device by using the bus interface, obtain the second data, and send the second data to the first element; and the first element is configured to: in the common scenario, obtain the second data input forwarded from the SE; wherein the first element comprises an application processor, a processor core in a trusted execution environment, TEE, a digital signal processor, or an application-specific integrated circuit. the bus interface is configured to be connected to an input/output, I/O, device (350, 450, 650, 710) and to the SE; the SE is configured to: determine whether an application that currently requires the I/O device to input data is an application in the SE; when a secure scenario is determined based on a fact that the application currently requiring input is an application in the SE, access the I/O device by using the bus interface, obtain first data input by the I/O device without sending the first data to the first element, and perform secure processing on the first data; and when a common scenario is determined based on a fact that the application currently requiring input is not an application in the SE access the I/O device by using the bus interface, obtain the second data, and send the second data to the first element; and the first element is configured to: in the common scenario, obtain the second data input forwarded from the SE; wherein the first element comprises an application processor, a processor core in a trusted execution environment, TEE, a digital signal processor, or an application-specific integrated circuit. determine whether an application that currently requires the I/O device to input data is an application in the SE; when a secure scenario is determined based on a fact that the application currently requiring input is an application in the SE, access the I/O device by using the bus interface, obtain first data input by the I/O device without sending the first data to the first element, and perform secure processing on the first data; and when a common scenario is determined based on a fact that the application currently requiring input is not an application in the SE access the I/O device by using the bus interface, obtain the second data, and send the second data to the first element; and the first element is configured to: in the common scenario, obtain the second data input forwarded from the SE; wherein the first element comprises an application processor, a processor core in a trusted execution environment, TEE, a digital signal processor, or an application-specific integrated circuit.