How to add GPIO outputs to the PXA2xx MFP configuration?
grinberg at compulab.co.il
Fri Mar 30 10:59:50 EDT 2012
On 03/28/12 20:12, Paul Parsons wrote:
> On PXA2xx platforms, the MFP API (described in Documentation/arm/pxa/mfp.txt)
> provides values for the following:
> 1. GPIO inputs (e.g. GPIO105_GPIO).
> 2. Alternate function inputs (e.g. GPIO105_CIF_DD_1).
> 3. Alternate function outputs (e.g. GPIO105_KP_MKOUT_2).
> It does not provide values for GPIO outputs (i.e. AF0 outputs).
> One cannot use the macro used by the MFP API internally - MFP_CFG_OUT() - to
> define new GPIO output values, since that macro is forbidden in platform code.
> Without the ability to add GPIO outputs to the MFP configuration, it is not
> possible to drive GPIO outputs high during sleep mode.
> This would be useful, for example, on the hx4700 platform, where driving the
> infrared powerdown GPIO 105 high during sleep mode would save some mA.
> So my question is: what method should one use to add GPIO outputs to the MFP
> One possible method, namely manually defining values in the platform code:
> MFP_PIN_GPIO105 | MFP_AF0 | MFP_DIR_OUT | MFP_LPM_DRIVE_HIGH,
Have you tried:
GPIO105_GPIO | MFP_LPM_DRIVE_HIGH,
This way it works on other boards.
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