Re: [PATCH] serial: 8250_dw: Improve unwritable LCR workaround

From: Tim Kryger
Date: Tue Oct 01 2013 - 13:13:19 EST


On Fri, Sep 27, 2013 at 12:49 AM, Heikki Krogerus
<heikki.krogerus@xxxxxxxxxxxxxxx> wrote:

> OK. The LCR issue is only a problem when the UART is configured with
> the busy functionality (UART_16550_COMPATIBLE == NO). Otherwise LRC is
> always accessible and this is not necessary.

Reading through the latest DW databook, I believe you are correct.

> We need a flag for the UART_16550_COMPATIBLE configuration, and
> use this WA based on that.

If I adjust the workaround to force the UART idle only when an LCR
write was ignored rather than doing it prior to any LCR write, would
that address your concerns?
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