Re: [PATCH v8 1/2] pinctrl: pinctrl-loongson2: add pinctrl driver support
From: Andy Shevchenko
Date: Fri Nov 11 2022 - 06:23:57 EST
On Fri, Nov 11, 2022 at 11:53:37AM +0800, Yinbo Zhu wrote:
> � 2022/11/9 ��11:40, Andy Shevchenko �
> > On Wed, Nov 09, 2022 at 02:11:21PM +0800, Yinbo Zhu wrote:
...
> > > +static const unsigned int lio_pins[] = {};
> > > +static const unsigned int uart2_pins[] = {};
> > > +static const unsigned int uart1_pins[] = {};
> > > +static const unsigned int camera_pins[] = {};
> > > +static const unsigned int dvo1_pins[] = {};
> > > +static const unsigned int dvo0_pins[] = {};
> >
> > No sure what this means.
> There are some fuzzy reuse relationships on loongson2, e.g., lio can be
> reused as gpio, which is one of the reserved gpios but the manual not
> indicates this gpio index.
The rule of thumb is to avoid putting something you are not able to test.
...
> > > + unsigned long reg = (unsigned long)pctrl->reg_base +
> > > + loongson2_pmx_groups[group_num].reg;
> >
> > Why casting?!
> There are some registers that determine the pin reuse relationship. For
> example, register A determines the sdio reuse relationship, and register
> A+offset determines the uart reuse relationship
I'm asking about something different. Why do you need casting for iomem offset?
...
> > > + val = readl((void *)reg);
> >
> > Ouch.
^^^ You see, this is a real issue with code, without fix which it's no go.
...
> > > + writel(val, (void *)reg);
> >
> > Ouch!
> I will keep writel/readl.
Yes, but you need to take care about annotations of the addresses (__iomem)
and remove ugly castings.
--
With Best Regards,
Andy Shevchenko