[i2c] I2C functionality bits

[Mark M. Hoffman]

Hi Till:

> On Thursday 02 November 2006 09:04, Jean Delvare wrote:
> > If you are doing bit-banging, please don't reimplement it, just use
> > i2c-algo-bit in your driver. It'll even export the right
> > functionalities for you (check drivers/i2c/algos/i2c-algo-bit.c to find
> > out which; it does indeed include I2C_FUNC_SMBUS_EMUL)

* Till Harbaum (Lists) <lists at harbaum.org> [2006-11-02 19:43:31 +0100]:
> The bitbanging is done inside the device. Linux doesn't see that at all and 
> you can easily build a device that uses the avrs hardware i2c. From the
> linux point of view they are just the same.

Jean: as I understand it, Till is shipping whole I2C transfers over USB to some
microcontroller... the firmware for that micro handles the actual bit banging.

Till: if you already specify I2C_FUNC_I2C, then just go ahead and add
I2C_FUNC_SMBUS_EMUL.  The latter is a strict subset of the former and the I2C
core will just take care of it.  Then sensors-detect (and many more chip
drivers) will work as you expect.  For an example of an existing bus driver
that does this, see drivers/i2c/busses/i2c-ibm_iic.c.

When do we get to see some code? ;)

Regards,

-- 
Mark M. Hoffman
mhoffman at lightlink.com