On Wed, Jan 20, 2021 at 08:40:32AM +0100, Oleksij Rempel wrote: > > Hi Dmitry, > > On Tue, Nov 17, 2020 at 04:31:38PM -0800, Dmitry Torokhov wrote: > > On Tue, Nov 10, 2020 at 09:50:41AM +0100, Oleksij Rempel wrote: > > > Convert multiple full duplex transfers in to a single transfer to reduce > > > CPU load. > > > > > > Current driver version support following filtering modes: > > > - ads7846_no_filter() - not filtered > > > - ads7846_debounce_filter() - driver specific debounce filter > > > - pdata->filter - platform specific debounce filter (do any platform > > > provides such filter?) > > > > > > Without filter this HW is not really usable, since the physic of > > > resistive touchscreen can provide some bounce effects. With driver > > > internal > > > filter, we have constant amount of retries + debounce retries if some > > > anomaly > > > was detected. > > > > > > High amount of tiny SPI transfers is the primer reason of high CPU load > > > and interrupt frequency. > > > > > > This patch create one SPI transfer with all fields and not optional > > > retires. If > > > bounce anomaly was detected, we will make more transfer if needed. > > > > > > Without this patch, we will get about 10% CPU load on iMX6S on pen-down > > > event. > > > For example by holding stylus on the screen. > > > > > > With this patch, depending in the amount of retries, the CPU load will > > > be 1% with "ti,debounce-rep = <3>". > > > > > > One buffer transfer allows us to use PIO FIFO or DMA engine, depending > > > on the platform. > > > > > > Signed-off-by: Oleksij Rempel <o.rem...@pengutronix.de> > > > > Applied, thank you. > > I can't find this patch in your git repository. Should I rebase it > against latest git and resend it?
Ugh, sorry, now applied for realz. Thanks. -- Dmitry
