2.7.1. Name

CEC_ADAP_G_PHYS_ADDR, CEC_ADAP_S_PHYS_ADDR - Get or set the physical address

2.7.2. Synopsis


int ioctl(int fd, CEC_ADAP_G_PHYS_ADDR, __u16 *argp)


int ioctl(int fd, CEC_ADAP_S_PHYS_ADDR, __u16 *argp)

2.7.3. Arguments


File descriptor returned by open().


Pointer to the CEC address.

2.7.4. Description

To query the current physical address applications call ioctl CEC_ADAP_G_PHYS_ADDR with a pointer to a __u16 where the driver stores the physical address.

To set a new physical address applications store the physical address in a __u16 and call ioctl CEC_ADAP_S_PHYS_ADDR with a pointer to this integer. The ioctl CEC_ADAP_S_PHYS_ADDR is only available if CEC_CAP_PHYS_ADDR is set (the ENOTTY error code will be returned otherwise). The ioctl CEC_ADAP_S_PHYS_ADDR can only be called by a file descriptor in initiator mode (see ioctls CEC_G_MODE and CEC_S_MODE), if not the EBUSY error code will be returned.

To clear an existing physical address use CEC_PHYS_ADDR_INVALID. The adapter will go to the unconfigured state.

If logical address types have been defined (see ioctl CEC_ADAP_S_LOG_ADDRS), then this ioctl will block until all requested logical addresses have been claimed. If the file descriptor is in non-blocking mode then it will not wait for the logical addresses to be claimed, instead it just returns 0.

A CEC_EVENT_STATE_CHANGE event is sent when the physical address changes.

The physical address is a 16-bit number where each group of 4 bits represent a digit of the physical address a.b.c.d where the most significant 4 bits represent 'a'. The CEC root device (usually the TV) has address Every device that is hooked up to an input of the TV has address a.0.0.0 (where 'a' is ≥ 1), devices hooked up to those in turn have addresses a.b.0.0, etc. So a topology of up to 5 devices deep is supported. The physical address a device shall use is stored in the EDID of the sink.

For example, the EDID for each HDMI input of the TV will have a different physical address of the form a.0.0.0 that the sources will read out and use as their physical address.

2.7.5. Return Value

On success 0 is returned, on error -1 and the errno variable is set appropriately. The generic error codes are described at the Generic Error Codes chapter.

The ioctl CEC_ADAP_S_PHYS_ADDR can return the following error codes:


The CEC_CAP_PHYS_ADDR capability wasn't set, so this ioctl is not supported.


Another filehandle is in exclusive follower or initiator mode, or the filehandle is in mode CEC_MODE_NO_INITIATOR.


The physical address is malformed.