Re: [PATCH v5 01/10] pinctrl: generic: Add bi-directional and output-enable

Hi Linus,

On Fri, May 12, 2017 at 11:04 AM, Linus Walleij
[off-list ref] wrote:

On Tue, May 9, 2017 at 12:54 PM, Geert Uytterhoeven
[off-list ref] wrote:

Oops missed this:

quoted

Hence I think we should not use generic pin properties, but consider these
settings to be part of pinmux configuration.
As having large tables in the driver is undesirable, I think storing the
settings in the "pinmux" property (by encoding them as flags passed to the
RZA1_PINMUX() macro) is our best option.

I think it is better to have large tables in the driver in this case.

Jacopo, Chris: Would two bits per pin/function (none, input, output, bidir)
be sufficient?
That makes one u16 per pin. So roughtly 12 ports x 16 pins => 384 bytes.
Plus code to handle it. After all not that bad...

It is the lesser evil.

Having unintelligible and hard to grasp stuff in the device tree that
no user will understand or dare to touch is not good, then it is better
to have it with the code, where it is being used, so the developers of
the driver can see it when they are dealing with this (quirky) hardware.

As you say this is actually fixing hardware bugs, we can expect these
quirky tables to be gone in the next hardware generation, right?

Let's hope so. Chris has a better crystal ball than I have ;-)

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
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