[i2c] [PATCH] OMAP: I2C driver for TI OMAP boards #3

Jean Delvare khali at linux-fr.org
Tue Aug 8 15:09:28 CEST 2006


Hi Komal,

> > Hmmm, this sounds like a bug somewhere. TRM for 5912 says the I2C
> > clock must be prescaled to be between 7 - 12 MHz [1]. The XOR input
> > clock is typically 12, 13 or 19.2 MHz. So we should have code that
> > produces:
> > 
> > XOR Mhz	Divider	Prescaler
> > 12		1	0
> > 13		2	1
> > 19.2	2	1
> > 
> > Then again the original old code produces something different too
> > [2]...
> > 
> > I suspect the original code had some hw workarounds and and later
> > code
> > may have a conversion bug somewhere :)
> > 
> > I suggest we keep the code as is for now since it's known to work on
> > all omaps, and then submit a follow-up patch later once we have
> > verified that that code based on the TRM works on all omaps.
> 
> I have updated the driver with all other review comments except comment
> on formula above by Jean. I can some part of description from Tony's
> explanation along with removing the following code line
> 
> /* Set Own Address */
> omap_i2c_write_reg(dev, OMAP_I2C_OA_REG, dev->own_address);
>  
> As it is not needed. Please confirm so that I can send the revised
> patch  soon.

Fine with me. If you remove that line, there are a few others you
should be able to remove as well (declaration of slave_add module
parameter, definition of DEFAULT_OWN, etc.)

Waiting for your updated patch :) Thanks for all the changes you
accepted to make, BTW. I believe the driver is in a better shape now.

-- 
Jean Delvare



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