Messages in this thread | | | From | Linus Walleij <> | Date | Wed, 9 Dec 2020 09:38:26 +0100 | Subject | Re: [BUG] SPI broken for SPI based panel drivers |
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On Sat, Dec 5, 2020 at 8:07 AM H. Nikolaus Schaller <hns@goldelico.com> wrote:
> I find it interesting that so far nobody wants to take responsibility > for a decision (...)
What causes some consternation in this discussion is the appeal to higher authority. The kernel community in general does not like authority/responsibility by way of formal hierarchy.
Have you read this document? Especially point 1) Decisions: https://www.kernel.org/doc/html/latest/process/management-style.html
(We can have a meta-discussion about this but it is not really your point I believe.)
> > What I can do is to provide just a skeleton for the table that you or Linus > > can fix/fill in and make a patch out of it. Is attached and the ??? is > > something you should discuss and define. > > Please take the attached diff, comment it here and define the question marks > according to your intention and then make a patch for the YAML bindings out > of it. (I can't do because I don't know your intentions and what to write into > the commit message).
I'll comment what I know, then you can send a proper patch to Mark. But you really need more people than me to look at this.
> + device node | cs-gpio | CS pin state active | Note > + ================+===============+=====================+===== > + spi-cs-high | - | H | > + - | - | L | > + spi-cs-high | ACTIVE_HIGH | H | > + - | ACTIVE_HIGH | L (or H ???) | 1
When using GPIO descriptors it will be enforced to ACTIVE_LOW (L) with an explicit warning in dmesg, see drivers/gpio/gpiolib-of.c
When using legacy GPIOs, will be enforced ACTIVE_LOW by the SPI core.
> + spi-cs-high | ACTIVE_LOW | H (or L ???) | 2
When using GPIO descriptors it will be enforced to ACTIVE_HIGH (H) with an explicit warning in dmesg, see drivers/gpio/gpiolib-of.c
> + 3) Effectively this rule defines that the ACTIVE level of the > + gpio has to be ignored
Nr 3 isn't tagged in the table.
Yours, Linus Walleij
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