Re: [PATCH v6 01/13] pinctrl: core: Add pinctrl_get_device()

[Linus Walleij <linus.walleij@xxxxxxxxxx>]

On Thu, Mar 9, 2023 at 3:19 PM Biju Das <biju.das.jz@xxxxxxxxxxxxxx> wrote:

> I have an IP which detects short circuit between the output terminals and
> disable the output from pwm pins ,when it detects short circuit to protect from
> system failure.
>
> pwm-pins are involved in this operation.
>
> From user space we need to configure the type of protection for this pins (eg: disable PWM output,
> when both pwm outputs are high at same time).

Why do you want to do this from user space?

It sounds like something the kernel should be doing.

The kernel has a PWM subsystem, and a pin control subsystem,
and we don't even have a userspace ABI for pin control.
Pin control is designed to avoid electrical disasters
and a driver can add further policy for sure.

If you want to add policy of different types to avoid electrical
disaster into the pin control driver, go ahead, just run it by
Geert so he's on board with the ideas.

> For that, we need to find a provider device (which provides gpt-pins).
>
> pinctrl_get_device() returns "current provider device" associated with fname/gname.
> If " current provider device" == "pwm device" do the configuration.

I don't understand this, sorry.

Yours,
Linus Walleij