On Fri, Nov 16, 2018 at 08:34:30AM +0100, Lothar Waßmann wrote:

Uwe Kleine-König [off-list ref] wrote:

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Hello Thierry,

On Thu, Nov 15, 2018 at 04:25:45PM +0100, Thierry Reding wrote:

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On Wed, Nov 14, 2018 at 10:51:20PM +0100, Uwe Kleine-König wrote:  

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On Wed, Nov 14, 2018 at 12:34:49PM +0100, Thierry Reding wrote:  

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Also dts writes don't need to lookup the needed GPIO numbers and pinctrl.  

Just to clarify: I don't think that we need to get the GPIO number
involved in this case, because we don't have to reconfigure the pin as
GPIO to make this work. The only reason that Michal's proposal did that
is because that was believed to be necessary. But if the pin can just be
configured with a 100k pull-up, that's enough to pull the pin high when
we need it.  

Unless the gpio happens to be configured as output at the wrong value.
Further I'm not sure if the pwm in disabled state actively pulls to 0
and if in this state the PU of the pin is good enough to ensure a one
here. That would need verification first.

No. You can disable the output driver via pinctrl, so that only the
selected pull-up/down is relevant. The pin function and GPIO register
settings don't matter at all in this case.

Is this about DSE=HI-Z in the pad control register? I didn't know about
this. I see this exists on i.MX6 but not on i.MX25. Also i.MX51 doesn't
seem to have this feature.

Best regards
Uwe

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Pengutronix e.K.                           | Uwe Kleine-König            |
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