cec-ioc-adap-g-caps.rst

.. -*- coding: utf-8; mode: rst -*-

.. _CEC_ADAP_G_CAPS:

*********************
ioctl CEC_ADAP_G_CAPS
*********************

Name
====

CEC_ADAP_G_CAPS - Query device capabilities

Synopsis
========

.. c:function:: int ioctl( int fd, CEC_ADAP_G_CAPS, struct cec_caps *argp )
    :name: CEC_ADAP_G_CAPS

Arguments
=========

``fd``
    File descriptor returned by :ref:`open() <cec-func-open>`.

``argp``


Description
===========

All cec devices must support :ref:`ioctl CEC_ADAP_G_CAPS <CEC_ADAP_G_CAPS>`. To query
device information, applications call the ioctl with a pointer to a
struct :c:type:`cec_caps`. The driver fills the structure and
returns the information to the application. The ioctl never fails.

.. tabularcolumns:: |p{1.2cm}|p{2.5cm}|p{13.8cm}|

.. c:type:: cec_caps

.. flat-table:: struct cec_caps
    :header-rows:  0
    :stub-columns: 0
    :widths:       1 1 16

    * - char
      - ``driver[32]``
      - The name of the cec adapter driver.
    * - char
      - ``name[32]``
      - The name of this CEC adapter. The combination ``driver`` and
	``name`` must be unique.
    * - __u32
      - ``capabilities``
      - The capabilities of the CEC adapter, see
	:ref:`cec-capabilities`.
    * - __u32
      - ``version``
      - CEC Framework API version, formatted with the ``KERNEL_VERSION()``
	macro.


.. tabularcolumns:: |p{4.4cm}|p{2.5cm}|p{10.6cm}|

.. _cec-capabilities:

.. flat-table:: CEC Capabilities Flags
    :header-rows:  0
    :stub-columns: 0
    :widths:       3 1 8

    * .. _`CEC-CAP-PHYS-ADDR`:

      - ``CEC_CAP_PHYS_ADDR``
      - 0x00000001
      - Userspace has to configure the physical address by calling
	:ref:`ioctl CEC_ADAP_S_PHYS_ADDR <CEC_ADAP_S_PHYS_ADDR>`. If
	this capability isn't set, then setting the physical address is
	handled by the kernel whenever the EDID is set (for an HDMI
	receiver) or read (for an HDMI transmitter).
    * .. _`CEC-CAP-LOG-ADDRS`:

      - ``CEC_CAP_LOG_ADDRS``
      - 0x00000002
      - Userspace has to configure the logical addresses by calling
	:ref:`ioctl CEC_ADAP_S_LOG_ADDRS <CEC_ADAP_S_LOG_ADDRS>`. If
	this capability isn't set, then the kernel will have configured
	this.
    * .. _`CEC-CAP-TRANSMIT`:

      - ``CEC_CAP_TRANSMIT``
      - 0x00000004
      - Userspace can transmit CEC messages by calling
	:ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>`. This implies that
	userspace can be a follower as well, since being able to transmit
	messages is a prerequisite of becoming a follower. If this
	capability isn't set, then the kernel will handle all CEC
	transmits and process all CEC messages it receives.
    * .. _`CEC-CAP-PASSTHROUGH`:

      - ``CEC_CAP_PASSTHROUGH``
      - 0x00000008
      - Userspace can use the passthrough mode by calling
	:ref:`ioctl CEC_S_MODE <CEC_S_MODE>`.
    * .. _`CEC-CAP-RC`:

      - ``CEC_CAP_RC``
      - 0x00000010
      - This adapter supports the remote control protocol.
    * .. _`CEC-CAP-MONITOR-ALL`:

      - ``CEC_CAP_MONITOR_ALL``
      - 0x00000020
      - The CEC hardware can monitor all messages, not just directed and
	broadcast messages.



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
:ref:`Generic Error Codes <gen-errors>` chapter.