Commit 77e04034 authored by Michael Trimarchi's avatar Michael Trimarchi Committed by Stefano Babic

imx: mx25: Remove SION bit in all pin-mux that are safe

SION bit should be used in the situation that we need
to read back the value of a pin and should not be set by
default macro.

We get some malfunction as raised by following thread

https://www.spinics.net/lists/linux-usb/msg162574.html

As reported by this application note:
https://www.nxp.com/docs/en/application-note/AN5078.pdf

The software input on (SION) bit is an option to force an input
path to be active regardless of the value driven by the
corresponding module. It is used when the nature direction
of a pin depending on selected alternative function is an output,
but it is needed to read the real logic value on a pin.

The SION bit can be used in:
• Loopback: the module of a selected alternative function drives
the pad and also receives the pad value as an input
• GPIO capture: the module of a selected alternative function
drives the pin and the value is captured by the GPIO

SION bit is not necessary when the pin is configured as a peripheral
apart specific silicon bug. If an application needs to have this
set, this should be done in board file or in dts file
Signed-off-by: default avatarMichael Trimarchi <michael@amarulasolutions.com>
Reviewed-by: default avatarBenoît Thébaudeau <benoit.thebaudeau.dev@gmail.com>
Signed-off-by: default avatarMichael Trimarchi <michael@amarulasolutions.com>
Reviewed-by: default avatarFabio Estevam <fabio.estevam@nxp.com>
parent c966c7b9
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