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diff --git a/Documentation/media/uapi/cec/cec-ioc-g-mode.rst b/Documentation/media/uapi/cec/cec-ioc-g-mode.rst deleted file mode 100644 index 2535b77e3459..000000000000 --- a/Documentation/media/uapi/cec/cec-ioc-g-mode.rst +++ /dev/null @@ -1,301 +0,0 @@ -.. 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_MODE: -.. _CEC_G_MODE: -.. _CEC_S_MODE: - -******************************** -ioctls CEC_G_MODE and CEC_S_MODE -******************************** - -CEC_G_MODE, CEC_S_MODE - Get or set exclusive use of the CEC adapter - -Synopsis -======== - -.. c:function:: int ioctl( int fd, CEC_G_MODE, __u32 *argp ) - :name: CEC_G_MODE - -.. c:function:: int ioctl( int fd, CEC_S_MODE, __u32 *argp ) - :name: CEC_S_MODE - -Arguments -========= - -``fd`` - File descriptor returned by :c:func:`open() <cec-open>`. - -``argp`` - Pointer to CEC mode. - -Description -=========== - -By default any filehandle can use :ref:`CEC_TRANSMIT`, but in order to prevent -applications from stepping on each others toes it must be possible to -obtain exclusive access to the CEC adapter. This ioctl sets the -filehandle to initiator and/or follower mode which can be exclusive -depending on the chosen mode. The initiator is the filehandle that is -used to initiate messages, i.e. it commands other CEC devices. The -follower is the filehandle that receives messages sent to the CEC -adapter and processes them. The same filehandle can be both initiator -and follower, or this role can be taken by two different filehandles. - -When a CEC message is received, then the CEC framework will decide how -it will be processed. If the message is a reply to an earlier -transmitted message, then the reply is sent back to the filehandle that -is waiting for it. In addition the CEC framework will process it. - -If the message is not a reply, then the CEC framework will process it -first. If there is no follower, then the message is just discarded and a -feature abort is sent back to the initiator if the framework couldn't -process it. If there is a follower, then the message is passed on to the -follower who will use :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>` to dequeue -the new message. The framework expects the follower to make the right -decisions. - -The CEC framework will process core messages unless requested otherwise -by the follower. The follower can enable the passthrough mode. In that -case, the CEC framework will pass on most core messages without -processing them and the follower will have to implement those messages. -There are some messages that the core will always process, regardless of -the passthrough mode. See :ref:`cec-core-processing` for details. - -If there is no initiator, then any CEC filehandle can use -:ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>`. If there is an exclusive -initiator then only that initiator can call -:ref:`CEC_TRANSMIT`. The follower can of course -always call :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>`. - -Available initiator modes are: - -.. tabularcolumns:: |p{5.6cm}|p{0.9cm}|p{11.0cm}| - -.. _cec-mode-initiator_e: - -.. flat-table:: Initiator Modes - :header-rows: 0 - :stub-columns: 0 - :widths: 3 1 16 - - * .. _`CEC-MODE-NO-INITIATOR`: - - - ``CEC_MODE_NO_INITIATOR`` - - 0x0 - - This is not an initiator, i.e. it cannot transmit CEC messages or - make any other changes to the CEC adapter. - * .. _`CEC-MODE-INITIATOR`: - - - ``CEC_MODE_INITIATOR`` - - 0x1 - - This is an initiator (the default when the device is opened) and - it can transmit CEC messages and make changes to the CEC adapter, - unless there is an exclusive initiator. - * .. _`CEC-MODE-EXCL-INITIATOR`: - - - ``CEC_MODE_EXCL_INITIATOR`` - - 0x2 - - This is an exclusive initiator and this file descriptor is the - only one that can transmit CEC messages and make changes to the - CEC adapter. If someone else is already the exclusive initiator - then an attempt to become one will return the ``EBUSY`` error code - error. - - -Available follower modes are: - -.. tabularcolumns:: |p{6.6cm}|p{0.9cm}|p{10.0cm}| - -.. _cec-mode-follower_e: - -.. cssclass:: longtable - -.. flat-table:: Follower Modes - :header-rows: 0 - :stub-columns: 0 - :widths: 3 1 16 - - * .. _`CEC-MODE-NO-FOLLOWER`: - - - ``CEC_MODE_NO_FOLLOWER`` - - 0x00 - - This is not a follower (the default when the device is opened). - * .. _`CEC-MODE-FOLLOWER`: - - - ``CEC_MODE_FOLLOWER`` - - 0x10 - - This is a follower and it will receive CEC messages unless there - is an exclusive follower. You cannot become a follower if - :ref:`CEC_CAP_TRANSMIT <CEC-CAP-TRANSMIT>` is not set or if :ref:`CEC_MODE_NO_INITIATOR <CEC-MODE-NO-INITIATOR>` - was specified, the ``EINVAL`` error code is returned in that case. - * .. _`CEC-MODE-EXCL-FOLLOWER`: - - - ``CEC_MODE_EXCL_FOLLOWER`` - - 0x20 - - This is an exclusive follower and only this file descriptor will - receive CEC messages for processing. If someone else is already - the exclusive follower then an attempt to become one will return - the ``EBUSY`` error code. You cannot become a follower if - :ref:`CEC_CAP_TRANSMIT <CEC-CAP-TRANSMIT>` is not set or if :ref:`CEC_MODE_NO_INITIATOR <CEC-MODE-NO-INITIATOR>` - was specified, the ``EINVAL`` error code is returned in that case. - * .. _`CEC-MODE-EXCL-FOLLOWER-PASSTHRU`: - - - ``CEC_MODE_EXCL_FOLLOWER_PASSTHRU`` - - 0x30 - - This is an exclusive follower and only this file descriptor will - receive CEC messages for processing. In addition it will put the - CEC device into passthrough mode, allowing the exclusive follower - to handle most core messages instead of relying on the CEC - framework for that. If someone else is already the exclusive - follower then an attempt to become one will return the ``EBUSY`` error - code. You cannot become a follower if :ref:`CEC_CAP_TRANSMIT <CEC-CAP-TRANSMIT>` - is not set or if :ref:`CEC_MODE_NO_INITIATOR <CEC-MODE-NO-INITIATOR>` was specified, - the ``EINVAL`` error code is returned in that case. - * .. _`CEC-MODE-MONITOR-PIN`: - - - ``CEC_MODE_MONITOR_PIN`` - - 0xd0 - - Put the file descriptor into pin monitoring mode. Can only be used in - combination with :ref:`CEC_MODE_NO_INITIATOR <CEC-MODE-NO-INITIATOR>`, - otherwise the ``EINVAL`` error code will be returned. - This mode requires that the :ref:`CEC_CAP_MONITOR_PIN <CEC-CAP-MONITOR-PIN>` - capability is set, otherwise the ``EINVAL`` error code is returned. - While in pin monitoring mode this file descriptor can receive the - ``CEC_EVENT_PIN_CEC_LOW`` and ``CEC_EVENT_PIN_CEC_HIGH`` events to see the - low-level CEC pin transitions. This is very useful for debugging. - This mode is only allowed if the process has the ``CAP_NET_ADMIN`` - capability. If that is not set, then the ``EPERM`` error code is returned. - * .. _`CEC-MODE-MONITOR`: - - - ``CEC_MODE_MONITOR`` - - 0xe0 - - Put the file descriptor into monitor mode. Can only be used in - combination with :ref:`CEC_MODE_NO_INITIATOR <CEC-MODE-NO-INITIATOR>`, - otherwise the ``EINVAL`` error code will be returned. - In monitor mode all messages this CEC - device transmits and all messages it receives (both broadcast - messages and directed messages for one its logical addresses) will - be reported. This is very useful for debugging. This is only - allowed if the process has the ``CAP_NET_ADMIN`` capability. If - that is not set, then the ``EPERM`` error code is returned. - * .. _`CEC-MODE-MONITOR-ALL`: - - - ``CEC_MODE_MONITOR_ALL`` - - 0xf0 - - Put the file descriptor into 'monitor all' mode. Can only be used - in combination with :ref:`CEC_MODE_NO_INITIATOR <CEC-MODE-NO-INITIATOR>`, otherwise - the ``EINVAL`` error code will be returned. In 'monitor all' mode all messages - this CEC device transmits and all messages it receives, including - directed messages for other CEC devices will be reported. This is - very useful for debugging, but not all devices support this. This - mode requires that the :ref:`CEC_CAP_MONITOR_ALL <CEC-CAP-MONITOR-ALL>` capability is set, - otherwise the ``EINVAL`` error code is returned. This is only allowed if - the process has the ``CAP_NET_ADMIN`` capability. If that is not - set, then the ``EPERM`` error code is returned. - - -Core message processing details: - -.. tabularcolumns:: |p{6.6cm}|p{10.9cm}| - -.. _cec-core-processing: - -.. flat-table:: Core Message Processing - :header-rows: 0 - :stub-columns: 0 - :widths: 1 8 - - * .. _`CEC-MSG-GET-CEC-VERSION`: - - - ``CEC_MSG_GET_CEC_VERSION`` - - The core will return the CEC version that was set with - :ref:`ioctl CEC_ADAP_S_LOG_ADDRS <CEC_ADAP_S_LOG_ADDRS>`, - except when in passthrough mode. In passthrough mode the core - does nothing and this message has to be handled by a follower - instead. - * .. _`CEC-MSG-GIVE-DEVICE-VENDOR-ID`: - - - ``CEC_MSG_GIVE_DEVICE_VENDOR_ID`` - - The core will return the vendor ID that was set with - :ref:`ioctl CEC_ADAP_S_LOG_ADDRS <CEC_ADAP_S_LOG_ADDRS>`, - except when in passthrough mode. In passthrough mode the core - does nothing and this message has to be handled by a follower - instead. - * .. _`CEC-MSG-ABORT`: - - - ``CEC_MSG_ABORT`` - - The core will return a Feature Abort message with reason - 'Feature Refused' as per the specification, except when in - passthrough mode. In passthrough mode the core does nothing - and this message has to be handled by a follower instead. - * .. _`CEC-MSG-GIVE-PHYSICAL-ADDR`: - - - ``CEC_MSG_GIVE_PHYSICAL_ADDR`` - - The core will report the current physical address, except when - in passthrough mode. In passthrough mode the core does nothing - and this message has to be handled by a follower instead. - * .. _`CEC-MSG-GIVE-OSD-NAME`: - - - ``CEC_MSG_GIVE_OSD_NAME`` - - The core will report the current OSD name that was set with - :ref:`ioctl CEC_ADAP_S_LOG_ADDRS <CEC_ADAP_S_LOG_ADDRS>`, - except when in passthrough mode. In passthrough mode the core - does nothing and this message has to be handled by a follower - instead. - * .. _`CEC-MSG-GIVE-FEATURES`: - - - ``CEC_MSG_GIVE_FEATURES`` - - The core will do nothing if the CEC version is older than 2.0, - otherwise it will report the current features that were set with - :ref:`ioctl CEC_ADAP_S_LOG_ADDRS <CEC_ADAP_S_LOG_ADDRS>`, - except when in passthrough mode. In passthrough mode the core - does nothing (for any CEC version) and this message has to be handled - by a follower instead. - * .. _`CEC-MSG-USER-CONTROL-PRESSED`: - - - ``CEC_MSG_USER_CONTROL_PRESSED`` - - If :ref:`CEC_CAP_RC <CEC-CAP-RC>` is set and if - :ref:`CEC_LOG_ADDRS_FL_ALLOW_RC_PASSTHRU <CEC-LOG-ADDRS-FL-ALLOW-RC-PASSTHRU>` - is set, then generate a remote control key - press. This message is always passed on to the follower(s). - * .. _`CEC-MSG-USER-CONTROL-RELEASED`: - - - ``CEC_MSG_USER_CONTROL_RELEASED`` - - If :ref:`CEC_CAP_RC <CEC-CAP-RC>` is set and if - :ref:`CEC_LOG_ADDRS_FL_ALLOW_RC_PASSTHRU <CEC-LOG-ADDRS-FL-ALLOW-RC-PASSTHRU>` - is set, then generate a remote control key - release. This message is always passed on to the follower(s). - * .. _`CEC-MSG-REPORT-PHYSICAL-ADDR`: - - - ``CEC_MSG_REPORT_PHYSICAL_ADDR`` - - The CEC framework will make note of the reported physical address - and then just pass the message on to the follower(s). - - - -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. - -The :ref:`ioctl CEC_S_MODE <CEC_S_MODE>` can return the following -error codes: - -EINVAL - The requested mode is invalid. - -EPERM - Monitor mode is requested, but the process does have the ``CAP_NET_ADMIN`` - capability. - -EBUSY - Someone else is already an exclusive follower or initiator. |