[U-Boot] [PATCH 0/7] Add a better USB keyboard polling method

Marek Vasut marex at denx.de
Sun Sep 21 12:45:56 CEST 2014


On Saturday, September 20, 2014 at 05:01:05 PM, Hans de Goede wrote:
> Hi Marek,
> 
> This time a patch-set for next :)
> 
> Currently one can choose between 2 poll methods for usb keyboards, both of
> which are suboptimal. One option is to use control messages to get reports,
> which some devices (e.g. my kvm) do not like. The other option is to use
> interrupt urbs, but usb_submit_int_msg waits for the interrupt packet to
> show up, meaning that each poll takes 40 ms, slowing anything else down
> tremendously.
> 
> This patch-sets adds a third method (only usable with ehci for now), which
> makes use of the int_queue concept in the ehci code. This allows us to
> submit an interrupt message, and then poll for the actual completion of
> this message giving us much lower latency then even the control message
> method (effectively this gives us 0 latency), while using standard
> interrupt messages which seems to keep keyboards much happier.

I'd be happy to just pick V2 as it would be. The patches look really nice.

Best regards,
Marek Vasut


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