Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 294 insertions, 0 deletions

diff --git a/Documentation/userspace-api/media/cec/cec-ioc-g-mode.rst b/Documentation/userspace-api/media/cec/cec-ioc-g-mode.rst
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+.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
+.. c:namespace:: CEC
+
+.. _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:macro:: CEC_G_MODE
+
+``int ioctl(int fd, CEC_G_MODE, __u32 *argp)``
+
+.. c:macro:: CEC_S_MODE
+
+``int ioctl(int fd, CEC_S_MODE, __u32 *argp)``
+
+Arguments
+=========
+
+``fd``
+    File descriptor returned by :c:func:`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{10.8cm}|
+
+.. _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{9.8cm}|
+
+.. _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.