cec-ioc-adap-g-phys-addr.rst (3310B)
1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later 2.. c:namespace:: CEC 3 4.. _CEC_ADAP_PHYS_ADDR: 5.. _CEC_ADAP_G_PHYS_ADDR: 6.. _CEC_ADAP_S_PHYS_ADDR: 7 8**************************************************** 9ioctls CEC_ADAP_G_PHYS_ADDR and CEC_ADAP_S_PHYS_ADDR 10**************************************************** 11 12Name 13==== 14 15CEC_ADAP_G_PHYS_ADDR, CEC_ADAP_S_PHYS_ADDR - Get or set the physical address 16 17Synopsis 18======== 19 20.. c:macro:: CEC_ADAP_G_PHYS_ADDR 21 22``int ioctl(int fd, CEC_ADAP_G_PHYS_ADDR, __u16 *argp)`` 23 24.. c:macro:: CEC_ADAP_S_PHYS_ADDR 25 26``int ioctl(int fd, CEC_ADAP_S_PHYS_ADDR, __u16 *argp)`` 27 28Arguments 29========= 30 31``fd`` 32 File descriptor returned by :c:func:`open()`. 33 34``argp`` 35 Pointer to the CEC address. 36 37Description 38=========== 39 40To query the current physical address applications call 41:ref:`ioctl CEC_ADAP_G_PHYS_ADDR <CEC_ADAP_G_PHYS_ADDR>` with a pointer to a __u16 where the 42driver stores the physical address. 43 44To set a new physical address applications store the physical address in 45a __u16 and call :ref:`ioctl CEC_ADAP_S_PHYS_ADDR <CEC_ADAP_S_PHYS_ADDR>` with a pointer to 46this integer. The :ref:`ioctl CEC_ADAP_S_PHYS_ADDR <CEC_ADAP_S_PHYS_ADDR>` is only available if 47``CEC_CAP_PHYS_ADDR`` is set (the ``ENOTTY`` error code will be returned 48otherwise). The :ref:`ioctl CEC_ADAP_S_PHYS_ADDR <CEC_ADAP_S_PHYS_ADDR>` can only be called 49by a file descriptor in initiator mode (see :ref:`CEC_S_MODE`), if not 50the ``EBUSY`` error code will be returned. 51 52To clear an existing physical address use ``CEC_PHYS_ADDR_INVALID``. 53The adapter will go to the unconfigured state. 54 55If logical address types have been defined (see :ref:`ioctl CEC_ADAP_S_LOG_ADDRS <CEC_ADAP_S_LOG_ADDRS>`), 56then this ioctl will block until all 57requested logical addresses have been claimed. If the file descriptor is in non-blocking mode 58then it will not wait for the logical addresses to be claimed, instead it just returns 0. 59 60A :ref:`CEC_EVENT_STATE_CHANGE <CEC-EVENT-STATE-CHANGE>` event is sent when the physical address 61changes. 62 63The physical address is a 16-bit number where each group of 4 bits 64represent a digit of the physical address a.b.c.d where the most 65significant 4 bits represent 'a'. The CEC root device (usually the TV) 66has address 0.0.0.0. Every device that is hooked up to an input of the 67TV has address a.0.0.0 (where 'a' is ≥ 1), devices hooked up to those in 68turn have addresses a.b.0.0, etc. So a topology of up to 5 devices deep 69is supported. The physical address a device shall use is stored in the 70EDID of the sink. 71 72For example, the EDID for each HDMI input of the TV will have a 73different physical address of the form a.0.0.0 that the sources will 74read out and use as their physical address. 75 76Return Value 77============ 78 79On success 0 is returned, on error -1 and the ``errno`` variable is set 80appropriately. The generic error codes are described at the 81:ref:`Generic Error Codes <gen-errors>` chapter. 82 83The :ref:`ioctl CEC_ADAP_S_PHYS_ADDR <CEC_ADAP_S_PHYS_ADDR>` can return the following 84error codes: 85 86ENOTTY 87 The ``CEC_CAP_PHYS_ADDR`` capability wasn't set, so this ioctl is not supported. 88 89EBUSY 90 Another filehandle is in exclusive follower or initiator mode, or the filehandle 91 is in mode ``CEC_MODE_NO_INITIATOR``. 92 93EINVAL 94 The physical address is malformed.