RE: [PATCH v6 06/13] drivers: pinctrl: renesas: Add RZ/G2L POEG driver support

[Biju Das <biju.das.jz@xxxxxxxxxxxxxx>]

Hi Andy Shevchenko,

Thanks for the feedback.

> Subject: Re: [PATCH v6 06/13] drivers: pinctrl: renesas: Add RZ/G2L POEG
> driver support
> 
> On Tue, Mar 7, 2023 at 12:10 PM Biju Das <biju.das.jz@xxxxxxxxxxxxxx> wrote:
> > > On Tue, Mar 7, 2023 at 10:53 AM Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> wrote:
> > > > > From: andy.shevchenko@xxxxxxxxx <andy.shevchenko@xxxxxxxxx>
> > > > > Sent: Monday, March 6, 2023 11:36 PM Mon, Mar 06, 2023 at
> > > > > 09:00:07AM
> > > > > +0000, Biju Das kirjoitti:
> 
> ...
> 
> > > > > > +static void rzg2l_poeg_write(struct rzg2l_poeg_chip *chip,
> > > > > > +u32
> > > > > > +data) {
> > > > > > +   iowrite32(data, chip->mmio); }
> > > > > > +
> > > > > > +static u32 rzg2l_poeg_read(struct rzg2l_poeg_chip *chip) {
> > > > > > +   return ioread32(chip->mmio); }
> > > > >
> > > > > Why not regmap MMIO?
> > > >
> > > > Some drivers used iowrite32, some uses writel, some uses regmap.
> > > >
> > > > will use regmap for read/write,If the preference is regmap MMIO as
> > > > it comes with spinlock for MMIO access.
> > >
> > > Lock can be disabled. It's up to the user of regmap.
> >
> > Ok, Just want to double check,
> > POEG has a single 32 bit register. So it worth to use regmap?
> > A simple readl/write is sufficient no??
> 
> It can be. But can you explain why you used iowriteXX() / ioreadXX() instead
> of writeX()/readX()?

It is a mistake from my side. I have referred RZ/G2L BSP poeg driver code[1],
initially and missed to change this.

[1]
https://github.com/renesas-rz/rz_linux-cip/blob/rz-5.10-cip17/drivers/pwm/poeg-rzg2l.c

Cheers,
Biju