[PATCH 0/5] serial: implement flow control for ASPEED VUART driver

Greg Kroah-Hartman gregkh at linuxfoundation.org
Sat Mar 24 02:51:16 AEDT 2018

On Wed, Mar 21, 2018 at 10:52:36AM +0800, Jeremy Kerr wrote:
> This series implements flow control for the ASPEED VUART driver. This
> hardware is slightly unusual in that the RX data rate can quickly
> overwhelm the flip buffer code, so the ldisc-driven throttle/unthrottle
> mechanisms don't entirely solve the problem.
> To do this, we have a couple of minor changes to the tty core, as well
> as an update to the tty proc interface to display buffer overrun metrics
> (entirely optional, but does allow us to see the problem).
> Then, we implement the standard throttle mechanism, and augment it with
> a fast-path to throttle if we overrun the flip buffers before the ldisc
> has had a chance to run.
> Questions and comments most welcome; I'm fairly new to the tty layer.

I've applied patch 2 here, can you redo the series again after fixing up
the first one and include the v2 of patch 5 so it's easier for me to
figure out what to really apply here?


greg k-h

More information about the Linux-aspeed mailing list