Re: [PATCH v1 12/16] pinctrl: starfive: Add pinctrl driver for StarFive SoCs

From: Andy Shevchenko
Date: Mon Oct 18 2021 - 11:48:17 EST


On Mon, Oct 18, 2021 at 6:35 PM Emil Renner Berthing <kernel@xxxxxxxx> wrote:
> On Tue, 12 Oct 2021 at 19:03, Andy Shevchenko <andy.shevchenko@xxxxxxxxx> wrote:
> > On Tue, Oct 12, 2021 at 4:43 PM Emil Renner Berthing <kernel@xxxxxxxx> wrote:

When answering, cut down your message to the point, please! It's a bit
annoying to remove overquoting...

...

> > > + case PIN_CONFIG_BIAS_DISABLE:
> >
> > > + mask |= PAD_BIAS_MASK;
> >
> > Use it...
> >
> > > + value = (value & ~PAD_BIAS_MASK) | PAD_BIAS_DISABLE;
> >
> > ...here. Ditto for the similar cases in this function and elsewhere.
>
> I don't follow. How do you want me to use mask? If I did value =
> (value & ~mask) | PAD_BIAS_DISABLE; then I'd wipe the previous
> configuration. Eg. suppose the first config is the drive strength and
> second disables bias. Then on the 2nd loop mask =
> PAD_DRIVE_STRENGTH_MASK | PAD_BIAS_MASK and the drive strength value
> would be wiped.

Collect masks and new values in temporary variables and apply them
once after the loop is done, no?

...

> > > + ret = clk_prepare_enable(clk);
> > > + if (ret) {
> >
> > > + reset_control_deassert(rst);
> >
> > Use devm_add_action_or_reset().
>
> I don't see how that is better.

Pity. The rule of thumb is to either try to use devm_*() everywhere in
the probe, or don't use it at all. Above is the more-or-less standard
pattern where devn_add_action_or_reset() is being used in the entire
kernel.

> Then I'd first need to call that and
> check for errors, but just on the line below enabling the clock the
> reset line is deasserted anyway, so then the action isn't needed any
> longer. So that 3 lines of code for devm_add_action_or_reset +
> lingering unneeded action or code to remove it again vs. just the line
> above.

Then don't use devm_*() at all. What's the point?

...

> > > + sfp->gc.of_node = dev->of_node;
> >
> > Isn't GPIO library do this for you?
>
> If it does I can't find it.

Heh... `man git grep`
Hint: `git grep -n 'of_node = .*of_node' -- drivers/gpio/gpiolib*`

--
With Best Regards,
Andy Shevchenko