On Mon, Jan 11, 2021 at 09:40:00PM +0800, DENG Qingfang wrote:

On Mon, Jan 11, 2021 at 7:04 PM Russell King - ARM Linux admin
[off-list ref] wrote:

quoted

FYI, Documentation/driver-api/gpio/consumer.rst says:

  For output GPIOs, the value provided becomes the initial output value.
  This helps avoid signal glitching during system startup.

Setting the pin to be an output, and then setting its initial value
does not avoid the glitch. You may wish to investigate whether you
can set the value before setting the pin as an output to avoid this
issue.

So, setting the Output Enable bit _after_ setting the direction and
initial value should avoid this issue. Right?

It depends on the hardware. I don't know how your hardware works, so
I can't say whether doing anything will result in correct behaviour,
or even work.

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