commit a94fc444257a39f0fc3b7d72c4a067b948437675
author Abtin Keshavarzian <abtink@google.com> Tue Mar 07 13:09:34 2023 -0800
committer GitHub <noreply@github.com> Tue Mar 07 13:09:34 2023 -0800
tree edf87413a2425db0f7c2774be2f9ad16b9ac2fcd
parent 130ef49cc409ee05c5dec35032280a45269a9080

[radio] mechanism to switch to PAN channel more quickly on CSL tx (#8701)

This commit adds `mRxChannelAfterTxDone` in `otRadioFrame` which
specifies the RX channel  after frame TX is done (after all retries
and ack received).

This is intended for situations where they may be delay in
interactions between OT stack and radio, as example this is used in
RCP and host architecture to make sure RCP switches to PAN channel
more quickly. In particular, this can help with CSL tx to a sleepy
child, where the child may use a different channel for CSL than the
PAN channel. After frame tx, we want the radio/RCP to go back to PAN
channel quickly to ensure that parent does not miss any tx from child
afterwards, e.g., child responding to the earlier CSL transmitted
frame from parent using PAN channel while radio still staying on CSL
channel.

This commit adds support for the `mRxChannelAfterTxDone` parameter in
spinel and posix host `RadioSpinel`. This is added in a backward
compatible way, i.e., if RCP is using a newer version but host is
older and does not provide the new parameter, RCP will use
`frame.mChannel` as default value for this, and if host is using a
newer version, older RCP will ignore it.