.. Permission is granted to copy, distribute and/or modify this
.. document under the terms of the GNU Free Documentation License,
.. Version 1.1 or any later version published by the Free Software
.. Foundation, with no Invariant Sections, no Front-Cover Texts
.. and no Back-Cover Texts. A copy of the license is included at
.. Documentation/media/uapi/fdl-appendix.rst.
..
.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
.. _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 :c:func:`open() <cec-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.
* .. _`CEC-CAP-NEEDS-HPD`:
- ``CEC_CAP_NEEDS_HPD``
- 0x00000040
- The CEC hardware is only active if the HDMI Hotplug Detect pin is
high. This makes it impossible to use CEC to wake up displays that
set the HPD pin low when in standby mode, but keep the CEC bus
alive.
* .. _`CEC-CAP-MONITOR-PIN`:
- ``CEC_CAP_MONITOR_PIN``
- 0x00000080
- The CEC hardware can monitor CEC pin changes from low to high voltage
and vice versa. When in pin monitoring mode the application will
receive ``CEC_EVENT_PIN_CEC_LOW`` and ``CEC_EVENT_PIN_CEC_HIGH`` events.
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.