cec-follower

CEC-FOLLOWER(1)                   User Commands                  CEC-FOLLOWER(1)



NAME
       cec-follower - An application to emulate CEC followers

SYNOPSIS
       cec-follower [-h] [-d <dev>] [other options]

DESCRIPTION
       The cec-follower tool is used to emulate CEC followers. Based on the
       configured logical address(es) of the CEC device it will emulate the CEC
       behavior accordingly.

       Configuring the CEC device is done using cec-ctl. Certain CEC
       functionalities are only emulated if the corresponding Device Features
       flag is set (these are set when configuring with cec-ctl). These are:

           - Audio Return Channel (RX and TX)
           - Audio Rate Control
           - Deck Control
           - Record TV screen

       cec-follower is basically a message loop, waiting for messages to arrive
       and taking the appropriate action for each message (incoming messages can
       be shown with the --show-msgs option). The follower maintains an internal
       state with appropriate parameters such as volume, current active source,
       power state and so on (state changes can be shown with the --show-state
       option).

       It also aims to be a reference implementation on how a follower should
       behave.

       cec-follower will keep track of incoming messages and look for violations
       of the CEC specification with regards to timings. For example, it will
       warn if it receives the same message again within 200ms after it replied
       <Feature Abort> ["Unrecognized Opcode"] to that message, and it will
       check that press and hold behavior is done properly.

       cec-follower will periodically send out polling messages to discover when
       a remote device is removed or a new one has appeared. When a device is
       removed, the recorded information about it is cleared. Each logical
       address is polled about once every 15 seconds. In between polls, removing
       a remote device or replacing it with a new one is not detected.

       When running compliance tests with cec-compliance, cec-follower should be
       run on the same device to act on incoming messages that are not replies
       to messages sent by the compliance tool. Before each test-run cec-
       follower should be restarted if it is running, to initialize the emulated
       device with a clean and known initial state.

OPTIONS
       -d, --device <dev>
              Use device <dev> as the CEC device. If <dev> is a number, then
              /dev/cec<dev> is used.

       -D, --driver <drv>
              Use a cec device that has driver name <drv>, as returned by the
              CEC_ADAP_G_CAPS ioctl.  This option can be combined with -a to
              uniquely identify a CEC device without having to rely on the
              device node number.

       -a, --adapter <adap-name>
              Use a cec device that has adapter name <adap-name>, as returned by
              the CEC_ADAP_G_CAPS ioctl.  This option can be combined with -D to
              uniquely identify a CEC device without having to rely on the
              device node number.

       -v, --verbose
              Turn on verbose reporting.

       -w, --wall-clock
              Show timestamps as wall-clock time. This also turns on verbose
              reporting.

       -T, --trace
              Trace all called ioctls. Useful for debugging.

       -h, --help
              Prints the help message.

       -n, --no-warnings
              Turn off warning messages.

       -m, --show-msgs
              Show received messages.

       -s, --show-state
              Show state changes from the emulated device.

       --service-by-dig-id
              Report digital services by digital ID instead of by channel.

       -i, --ignore <la>,<opcode>
              Ignore messages from logical address <la> and opcode <opcode>.
              'all' can be used for <la> or <opcode> to match all logical
              addresses or opcodes.


EXIT STATUS
       On success, it returns 0. Otherwise, it will return the error code.

BUGS
       This manual page is a work in progress.

       Bug reports or questions about this utility should be sent to the linux-
       media@vger.kernel.org mailinglist.

SEE ALSO
       cec-compliance(1), cec-ctl(1)



v4l-utils 1.20.0                   August 2016                   CEC-FOLLOWER(1)