Shubhrajyoti D <[email protected]> writes:

> From: Vikram Pandita <[email protected]>
>
> In case a peripheral is driving SDA bus low (ie. a start condition), provide
> a constant clock output using the test mode of the OMAP I2C controller to
> try and clear the bus. Soft reset I2C controller after attempting the bus 
> clear
> to ensure that controller is in a good state.
>
> Based upon Vikram Pandita's patch from TI Android 3.0 kernel and modified for
> mainline by Jon Hunter. 
>
> A couple differences from the original patch ...
> 1. Add a new function for bus clear
> 2. Ensure that the CON.I2C_EN bit is set when using the SYSTEST feature to
>    output a permanent clock. This bit needs to be set and tpyically it would
>    be set by the unidle function but this is not the case for all OMAP
>    generations.
> 3. Program the SYSTEST setting only the bits we care about. However, restore
>    SYSTEST registers to there original state as some OMAP generations do not
>    implement perform a soft-reset.
> 4. Clear the CON register after performing the bus clear, so when we call the
>    init function the controller is disabled and the init function will
>    re-enable later.
>
> Cc:  Kevin Hilman <[email protected]>
> Signed-off-by: Vikram Pandita <[email protected]>
> Signed-off-by: Jon Hunter <[email protected]>
> Signed-off-by: Shubhrajyoti D <[email protected]>
> ---
> Original patch can be found here:
> http://git.omapzoom.org/?p=kernel/omap.git;a=commit;h=a2ab04192ba25e60f95ba1ff3af5601a2d7b5bd1
> applies on Kevin's for_3.3/i2c/misc

Please also explain how this was tested, and on what platforms.

Thanks,

Kevin
--
To unsubscribe from this list: send the line "unsubscribe linux-i2c" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to