[PATCH 1/2] drm/kms: Make i2c buses faster

Alan Cox alan at lxorguk.ukuu.org.uk
Fri Oct 21 06:32:44 PDT 2011

On Fri, 21 Oct 2011 09:08:30 +0200
Jean Delvare <jdelvare at suse.de> wrote:

> A udelay value of 20 leads to an I2C bus running at only 25 kbps. A
> value of 40 as the nouveau driver has is even slower at 12.5 kbps. I2C
> devices can typically operate faster than this, 50 kbps should be fine
> for all devices (and compliant devices can always stretch the clock is
> needed.)

That depends on your cable, drive and signal quality. It's not something
you just turn up because it seems a good idea. Reliability is MUCH more
important than shaving microseconds off monitor probe times.


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