CEC_ADAP_G_PHYS_ADDR, CEC_ADAP_S_PHYS_ADDR — Get or set the physical address
File descriptor returned by
Note: this documents the proposed CEC API. This API is not yet finalized and is currently only available as a staging kernel module.
To query the current physical address applications call the
CEC_ADAP_G_PHYS_ADDR ioctl with a pointer to an __u16
where the driver stores the physical address.
To set a new physical address applications store the physical address in
an __u16 and call the
CEC_ADAP_S_PHYS_ADDR ioctl with a
pointer to this integer.
CEC_ADAP_S_PHYS_ADDR is only
CEC_CAP_PHYS_ADDR is set (ENOTTY error code will be returned
can only be called by a file handle in initiator mode (see
CEC_S_MODE), if not
EBUSY error code will be returned.
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 0.0.0.0. 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.
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.