Implement txctrl.txen and rxctrl.rxen as follows:
* txctrl.txen
The txen bit controls whether the Tx channel is active. When cleared,
transmission of Tx FIFO contents is suppressed, and the txd pin is
driven high.
* rxctrl.rxen:
The rxen bit controls whether the Rx channel is active. When cleared,
the state of the rxd pin is ignored, and no characters will be
enqueued into the Rx FIFO.
Therefore, the Tx FIFO should not be dequeued when txctrl.txen is
cleared, and the Rx FIFO should not be enqueued when rxctrl.rxen is
cleared.
Signed-off-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20260312033201.1619554-2-frank.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
(cherry picked from commit e6051fa61b)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
e42c35ff87