summaryrefslogtreecommitdiff
path: root/Documentation/media/uapi/cec/cec-ioc-receive.rst
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/media/uapi/cec/cec-ioc-receive.rst')
-rw-r--r--Documentation/media/uapi/cec/cec-ioc-receive.rst418
1 files changed, 172 insertions, 246 deletions
diff --git a/Documentation/media/uapi/cec/cec-ioc-receive.rst b/Documentation/media/uapi/cec/cec-ioc-receive.rst
index d585b1bba6ac..bdf015b1d1dc 100644
--- a/Documentation/media/uapi/cec/cec-ioc-receive.rst
+++ b/Documentation/media/uapi/cec/cec-ioc-receive.rst
@@ -86,173 +86,126 @@ result.
:stub-columns: 0
:widths: 1 1 16
+ * - __u64
+ - ``tx_ts``
+ - Timestamp in ns of when the last byte of the message was transmitted.
+ The timestamp has been taken from the ``CLOCK_MONOTONIC`` clock. To access
+ the same clock from userspace use :c:func:`clock_gettime`.
+ * - __u64
+ - ``rx_ts``
+ - Timestamp in ns of when the last byte of the message was received.
+ The timestamp has been taken from the ``CLOCK_MONOTONIC`` clock. To access
+ the same clock from userspace use :c:func:`clock_gettime`.
+ * - __u32
+ - ``len``
+ - The length of the message. For :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` this is filled in
+ by the application. The driver will fill this in for
+ :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>`. For :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` it will be
+ filled in by the driver with the length of the reply message if ``reply`` was set.
+ * - __u32
+ - ``timeout``
+ - The timeout in milliseconds. This is the time the device will wait
+ for a message to be received before timing out. If it is set to 0,
+ then it will wait indefinitely when it is called by :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>`.
+ If it is 0 and it is called by :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>`,
+ then it will be replaced by 1000 if the ``reply`` is non-zero or
+ ignored if ``reply`` is 0.
+ * - __u32
+ - ``sequence``
+ - A non-zero sequence number is automatically assigned by the CEC framework
+ for all transmitted messages. It is used by the CEC framework when it queues
+ the transmit result (when transmit was called in non-blocking mode). This
+ allows the application to associate the received message with the original
+ transmit.
+ * - __u32
+ - ``flags``
+ - Flags. See :ref:`cec-msg-flags` for a list of available flags.
+ * - __u8
+ - ``tx_status``
+ - The status bits of the transmitted message. See
+ :ref:`cec-tx-status` for the possible status values. It is 0 if
+ this messages was received, not transmitted.
+ * - __u8
+ - ``msg[16]``
+ - The message payload. For :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` this is filled in by the
+ application. The driver will fill this in for :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>`.
+ For :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` it will be filled in by the driver with
+ the payload of the reply message if ``timeout`` was set.
+ * - __u8
+ - ``reply``
+ - Wait until this message is replied. If ``reply`` is 0 and the
+ ``timeout`` is 0, then don't wait for a reply but return after
+ transmitting the message. Ignored by :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>`.
+ The case where ``reply`` is 0 (this is the opcode for the Feature Abort
+ message) and ``timeout`` is non-zero is specifically allowed to make it
+ possible to send a message and wait up to ``timeout`` milliseconds for a
+ Feature Abort reply. In this case ``rx_status`` will either be set
+ to :ref:`CEC_RX_STATUS_TIMEOUT <CEC-RX-STATUS-TIMEOUT>` or
+ :ref:`CEC_RX_STATUS_FEATURE_ABORT <CEC-RX-STATUS-FEATURE-ABORT>`.
+
+ If the transmitter message is ``CEC_MSG_INITIATE_ARC`` then the ``reply``
+ values ``CEC_MSG_REPORT_ARC_INITIATED`` and ``CEC_MSG_REPORT_ARC_TERMINATED``
+ are processed differently: either value will match both possible replies.
+ The reason is that the ``CEC_MSG_INITIATE_ARC`` message is the only CEC
+ message that has two possible replies other than Feature Abort. The
+ ``reply`` field will be updated with the actual reply so that it is
+ synchronized with the contents of the received message.
+ * - __u8
+ - ``rx_status``
+ - The status bits of the received message. See
+ :ref:`cec-rx-status` for the possible status values. It is 0 if
+ this message was transmitted, not received, unless this is the
+ reply to a transmitted message. In that case both ``rx_status``
+ and ``tx_status`` are set.
+ * - __u8
+ - ``tx_status``
+ - The status bits of the transmitted message. See
+ :ref:`cec-tx-status` for the possible status values. It is 0 if
+ this messages was received, not transmitted.
+ * - __u8
+ - ``tx_arb_lost_cnt``
+ - A counter of the number of transmit attempts that resulted in the
+ Arbitration Lost error. This is only set if the hardware supports
+ this, otherwise it is always 0. This counter is only valid if the
+ :ref:`CEC_TX_STATUS_ARB_LOST <CEC-TX-STATUS-ARB-LOST>` status bit is set.
+ * - __u8
+ - ``tx_nack_cnt``
+ - A counter of the number of transmit attempts that resulted in the
+ Not Acknowledged error. This is only set if the hardware supports
+ this, otherwise it is always 0. This counter is only valid if the
+ :ref:`CEC_TX_STATUS_NACK <CEC-TX-STATUS-NACK>` status bit is set.
+ * - __u8
+ - ``tx_low_drive_cnt``
+ - A counter of the number of transmit attempts that resulted in the
+ Arbitration Lost error. This is only set if the hardware supports
+ this, otherwise it is always 0. This counter is only valid if the
+ :ref:`CEC_TX_STATUS_LOW_DRIVE <CEC-TX-STATUS-LOW-DRIVE>` status bit is set.
+ * - __u8
+ - ``tx_error_cnt``
+ - A counter of the number of transmit errors other than Arbitration
+ Lost or Not Acknowledged. This is only set if the hardware
+ supports this, otherwise it is always 0. This counter is only
+ valid if the :ref:`CEC_TX_STATUS_ERROR <CEC-TX-STATUS-ERROR>` status bit is set.
+
+
+.. _cec-msg-flags:
+
+.. flat-table:: Flags for struct cec_msg
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 3 1 4
- - .. row 1
-
- - __u64
-
- - ``tx_ts``
-
- - Timestamp in ns of when the last byte of the message was transmitted.
- The timestamp has been taken from the ``CLOCK_MONOTONIC`` clock. To access
- the same clock from userspace use :c:func:`clock_gettime`.
-
- - .. row 2
-
- - __u64
-
- - ``rx_ts``
-
- - Timestamp in ns of when the last byte of the message was received.
- The timestamp has been taken from the ``CLOCK_MONOTONIC`` clock. To access
- the same clock from userspace use :c:func:`clock_gettime`.
-
- - .. row 3
-
- - __u32
-
- - ``len``
-
- - The length of the message. For :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` this is filled in
- by the application. The driver will fill this in for
- :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>`. For :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` it will be
- filled in by the driver with the length of the reply message if ``reply`` was set.
-
- - .. row 4
-
- - __u32
-
- - ``timeout``
-
- - The timeout in milliseconds. This is the time the device will wait
- for a message to be received before timing out. If it is set to 0,
- then it will wait indefinitely when it is called by :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>`.
- If it is 0 and it is called by :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>`,
- then it will be replaced by 1000 if the ``reply`` is non-zero or
- ignored if ``reply`` is 0.
-
- - .. row 5
-
- - __u32
-
- - ``sequence``
-
- - A non-zero sequence number is automatically assigned by the CEC framework
- for all transmitted messages. It is used by the CEC framework when it queues
- the transmit result (when transmit was called in non-blocking mode). This
- allows the application to associate the received message with the original
- transmit.
-
- - .. row 6
-
- - __u32
-
- - ``flags``
-
- - Flags. No flags are defined yet, so set this to 0.
-
- - .. row 7
-
- - __u8
-
- - ``tx_status``
-
- - The status bits of the transmitted message. See
- :ref:`cec-tx-status` for the possible status values. It is 0 if
- this messages was received, not transmitted.
-
- - .. row 8
-
- - __u8
-
- - ``msg[16]``
-
- - The message payload. For :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` this is filled in by the
- application. The driver will fill this in for :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>`.
- For :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` it will be filled in by the driver with
- the payload of the reply message if ``timeout`` was set.
-
- - .. row 8
-
- - __u8
-
- - ``reply``
-
- - Wait until this message is replied. If ``reply`` is 0 and the
- ``timeout`` is 0, then don't wait for a reply but return after
- transmitting the message. Ignored by :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>`.
- The case where ``reply`` is 0 (this is the opcode for the Feature Abort
- message) and ``timeout`` is non-zero is specifically allowed to make it
- possible to send a message and wait up to ``timeout`` milliseconds for a
- Feature Abort reply. In this case ``rx_status`` will either be set
- to :ref:`CEC_RX_STATUS_TIMEOUT <CEC-RX-STATUS-TIMEOUT>` or
- :ref:`CEC_RX_STATUS_FEATURE_ABORT <CEC-RX-STATUS-FEATURE-ABORT>`.
-
- - .. row 9
-
- - __u8
-
- - ``rx_status``
-
- - The status bits of the received message. See
- :ref:`cec-rx-status` for the possible status values. It is 0 if
- this message was transmitted, not received, unless this is the
- reply to a transmitted message. In that case both ``rx_status``
- and ``tx_status`` are set.
-
- - .. row 10
-
- - __u8
-
- - ``tx_status``
-
- - The status bits of the transmitted message. See
- :ref:`cec-tx-status` for the possible status values. It is 0 if
- this messages was received, not transmitted.
-
- - .. row 11
-
- - __u8
-
- - ``tx_arb_lost_cnt``
-
- - A counter of the number of transmit attempts that resulted in the
- Arbitration Lost error. This is only set if the hardware supports
- this, otherwise it is always 0. This counter is only valid if the
- :ref:`CEC_TX_STATUS_ARB_LOST <CEC-TX-STATUS-ARB-LOST>` status bit is set.
-
- - .. row 12
-
- - __u8
-
- - ``tx_nack_cnt``
-
- - A counter of the number of transmit attempts that resulted in the
- Not Acknowledged error. This is only set if the hardware supports
- this, otherwise it is always 0. This counter is only valid if the
- :ref:`CEC_TX_STATUS_NACK <CEC-TX-STATUS-NACK>` status bit is set.
-
- - .. row 13
-
- - __u8
-
- - ``tx_low_drive_cnt``
-
- - A counter of the number of transmit attempts that resulted in the
- Arbitration Lost error. This is only set if the hardware supports
- this, otherwise it is always 0. This counter is only valid if the
- :ref:`CEC_TX_STATUS_LOW_DRIVE <CEC-TX-STATUS-LOW-DRIVE>` status bit is set.
-
- - .. row 14
-
- - __u8
-
- - ``tx_error_cnt``
+ * .. _`CEC-MSG-FL-REPLY-TO-FOLLOWERS`:
- - A counter of the number of transmit errors other than Arbitration
- Lost or Not Acknowledged. This is only set if the hardware
- supports this, otherwise it is always 0. This counter is only
- valid if the :ref:`CEC_TX_STATUS_ERROR <CEC-TX-STATUS-ERROR>` status bit is set.
+ - ``CEC_MSG_FL_REPLY_TO_FOLLOWERS``
+ - 1
+ - If a CEC transmit expects a reply, then by default that reply is only sent to
+ the filehandle that called :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>`. If this
+ flag is set, then the reply is also sent to all followers, if any. If the
+ filehandle that called :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` is also a
+ follower, then that filehandle will receive the reply twice: once as the
+ result of the :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>`, and once via
+ :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>`.
.. tabularcolumns:: |p{5.6cm}|p{0.9cm}|p{11.0cm}|
@@ -264,64 +217,46 @@ result.
:stub-columns: 0
:widths: 3 1 16
-
- - .. _`CEC-TX-STATUS-OK`:
-
- - ``CEC_TX_STATUS_OK``
-
- - 0x01
-
- - The message was transmitted successfully. This is mutually
- exclusive with :ref:`CEC_TX_STATUS_MAX_RETRIES <CEC-TX-STATUS-MAX-RETRIES>`. Other bits can still
- be set if earlier attempts met with failure before the transmit
- was eventually successful.
-
- - .. _`CEC-TX-STATUS-ARB-LOST`:
-
- - ``CEC_TX_STATUS_ARB_LOST``
-
- - 0x02
-
- - CEC line arbitration was lost.
-
- - .. _`CEC-TX-STATUS-NACK`:
-
- - ``CEC_TX_STATUS_NACK``
-
- - 0x04
-
- - Message was not acknowledged.
-
- - .. _`CEC-TX-STATUS-LOW-DRIVE`:
-
- - ``CEC_TX_STATUS_LOW_DRIVE``
-
- - 0x08
-
- - Low drive was detected on the CEC bus. This indicates that a
- follower detected an error on the bus and requests a
- retransmission.
-
- - .. _`CEC-TX-STATUS-ERROR`:
-
- - ``CEC_TX_STATUS_ERROR``
-
- - 0x10
-
- - Some error occurred. This is used for any errors that do not fit
- the previous two, either because the hardware could not tell which
- error occurred, or because the hardware tested for other
- conditions besides those two.
-
- - .. _`CEC-TX-STATUS-MAX-RETRIES`:
-
- - ``CEC_TX_STATUS_MAX_RETRIES``
-
- - 0x20
-
- - The transmit failed after one or more retries. This status bit is
- mutually exclusive with :ref:`CEC_TX_STATUS_OK <CEC-TX-STATUS-OK>`. Other bits can still
- be set to explain which failures were seen.
+ * .. _`CEC-TX-STATUS-OK`:
+
+ - ``CEC_TX_STATUS_OK``
+ - 0x01
+ - The message was transmitted successfully. This is mutually
+ exclusive with :ref:`CEC_TX_STATUS_MAX_RETRIES <CEC-TX-STATUS-MAX-RETRIES>`. Other bits can still
+ be set if earlier attempts met with failure before the transmit
+ was eventually successful.
+ * .. _`CEC-TX-STATUS-ARB-LOST`:
+
+ - ``CEC_TX_STATUS_ARB_LOST``
+ - 0x02
+ - CEC line arbitration was lost.
+ * .. _`CEC-TX-STATUS-NACK`:
+
+ - ``CEC_TX_STATUS_NACK``
+ - 0x04
+ - Message was not acknowledged.
+ * .. _`CEC-TX-STATUS-LOW-DRIVE`:
+
+ - ``CEC_TX_STATUS_LOW_DRIVE``
+ - 0x08
+ - Low drive was detected on the CEC bus. This indicates that a
+ follower detected an error on the bus and requests a
+ retransmission.
+ * .. _`CEC-TX-STATUS-ERROR`:
+
+ - ``CEC_TX_STATUS_ERROR``
+ - 0x10
+ - Some error occurred. This is used for any errors that do not fit
+ the previous two, either because the hardware could not tell which
+ error occurred, or because the hardware tested for other
+ conditions besides those two.
+ * .. _`CEC-TX-STATUS-MAX-RETRIES`:
+
+ - ``CEC_TX_STATUS_MAX_RETRIES``
+ - 0x20
+ - The transmit failed after one or more retries. This status bit is
+ mutually exclusive with :ref:`CEC_TX_STATUS_OK <CEC-TX-STATUS-OK>`. Other bits can still
+ be set to explain which failures were seen.
.. tabularcolumns:: |p{5.6cm}|p{0.9cm}|p{11.0cm}|
@@ -333,32 +268,23 @@ result.
:stub-columns: 0
:widths: 3 1 16
+ * .. _`CEC-RX-STATUS-OK`:
- - .. _`CEC-RX-STATUS-OK`:
-
- - ``CEC_RX_STATUS_OK``
-
- - 0x01
-
- - The message was received successfully.
-
- - .. _`CEC-RX-STATUS-TIMEOUT`:
-
- - ``CEC_RX_STATUS_TIMEOUT``
-
- - 0x02
-
- - The reply to an earlier transmitted message timed out.
-
- - .. _`CEC-RX-STATUS-FEATURE-ABORT`:
-
- - ``CEC_RX_STATUS_FEATURE_ABORT``
+ - ``CEC_RX_STATUS_OK``
+ - 0x01
+ - The message was received successfully.
+ * .. _`CEC-RX-STATUS-TIMEOUT`:
- - 0x04
+ - ``CEC_RX_STATUS_TIMEOUT``
+ - 0x02
+ - The reply to an earlier transmitted message timed out.
+ * .. _`CEC-RX-STATUS-FEATURE-ABORT`:
- - The message was received successfully but the reply was
- ``CEC_MSG_FEATURE_ABORT``. This status is only set if this message
- was the reply to an earlier transmitted message.
+ - ``CEC_RX_STATUS_FEATURE_ABORT``
+ - 0x04
+ - The message was received successfully but the reply was
+ ``CEC_MSG_FEATURE_ABORT``. This status is only set if this message
+ was the reply to an earlier transmitted message.