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diff --git a/Documentation/userspace-api/media/cec/cec-ioc-adap-g-caps.rst b/Documentation/userspace-api/media/cec/cec-ioc-adap-g-caps.rst new file mode 100644 index 000000000..d5e014ce1 --- /dev/null +++ b/Documentation/userspace-api/media/cec/cec-ioc-adap-g-caps.rst @@ -0,0 +1,146 @@ +.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later +.. c:namespace:: CEC + +.. _CEC_ADAP_G_CAPS: + +********************* +ioctl CEC_ADAP_G_CAPS +********************* + +Name +==== + +CEC_ADAP_G_CAPS - Query device capabilities + +Synopsis +======== + +.. c:macro:: CEC_ADAP_G_CAPS + +``int ioctl(int fd, CEC_ADAP_G_CAPS, struct cec_caps *argp)`` + +Arguments +========= + +``fd`` + File descriptor returned by :c: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{13.6cm}| + +.. 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 + - ``available_log_addrs`` + - The maximum number of logical addresses that can be configured. + * - __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{10.4cm}| + +.. _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. + * .. _`CEC-CAP-CONNECTOR-INFO`: + + - ``CEC_CAP_CONNECTOR_INFO`` + - 0x00000100 + - If this capability is set, then :ref:`CEC_ADAP_G_CONNECTOR_INFO` can + be used. + +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. |