I2C 2.1 support for High Speed I2C, 3.4 Mb/s

Mark Studebaker mds at mds.gotdns.com
Sun Apr 24 02:32:51 CEST 2005

I don't think anybody's ever asked us about it, much less worked on it.
Looks like HS mode was defined in I2C V2.0 in 1998.

Would you be working on a bit-banging driver or is here an I2C bus master
out there supporting HS mode?

If you are going to write a driver please keep in touch and let us know
how it's going and what API extensions you propose.

If a bit-banger big desision is to mod and/or start from i2c-algo-bit or i2c-algo-biths.
algo-bit is 33% duty cycle, biths is 50% duty cycle and in theory can
go faster. However i2c spec says HS mode is 33% duty cycle. Go figure.
See TODO for more info.


Woodruff, Richard wrote:
> Hello,
> I just started grep'ing around to see if HS I2C support is implemented
> and have not found anything.
> Has any one used this with Linux before?  The Spec would indicate that a
> slow/fast preamble of sorts is used followed by fast data transfers.
> We will likely add a driver if none exists, but knowing its been done
> before is always comforting. 
> Regards/Thanks,
> Richard W.

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