Re: [PATCH v2 2/2] pinctrl: iproc: use unique name for irq chip

From: Chris Packham
Date: Sun Oct 13 2019 - 17:03:32 EST


Hi LinusW, Scott, Geert, MarcZ,

On Mon, 2019-10-07 at 10:10 -0700, Scott Branden wrote:
>
> On 2019-10-07 1:14 a.m., Marc Zyngier wrote:
> > On Mon, 07 Oct 2019 08:30:50 +0100,
> > Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
> > > Hi Chris,
> > >
> > > CC MarcZ
> > >
> > > On Thu, Oct 3, 2019 at 2:03 AM Chris Packham
> > > <chris.packham@xxxxxxxxxxxxxxxxxxx> wrote:
> > > > Use the dev_name(dev) for the irqc->name so that we get unique names
> > > > when we have multiple instances of this driver.
> > > >
> > > > Signed-off-by: Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx>
> > >
> > > A while ago, Marc Zyngier pointed out that the irq_chip .name field
> > > should contain the device's class name, not the instance's name.
> > > Hence the current code is correct?
> >
> > Thanks Geert for looping me in. The main reasons why I oppose this
> > kind of "let's show as much information as we can in /proc/interrupts"
> > are:
> >
> > - It clutters the output badly: the formatting of this file, which is
> > bad enough when you have a small number of CPUs, becomes unreadable
> > when you have a large number of them *and* stupidly long strings
> > that only make sense on a given platform.
> >
> > - Like it or not, /proc is ABI. We don't change things randomly there
> > without a good reason, and debugging isn't one of them.
> >
> > - Debug information belongs to debugfs, where we already have plenty
> > of stuff (see CONFIG_GENERIC_IRQ_DEBUGFS). I'd rather we improve
> > this infrastructure if needed, rather than add platform specific
> > hacks.
> >
> > </rant>
> >
> > Thanks,
> >
> > M.
>
> Thanks Marc/Geert. Sounds like we should drop patch 2 from series.

Sorry for not responding earlier (I was on vacation for a week). I'm
fine with dropping this patch.

> >
> > > See also "[PATCH 0/4] irqchip: renesas: Use proper irq_chip name and parent"
> > > (https://lore.kernel.org/lkml/20190607095858.10028-1-geert+renesas@xxxxxxxxx/)
> > > Note that the irqchip patches in that series have been applied; the gpio
> > > patches haven't been applied yet.
> > >
> > > > --- a/drivers/pinctrl/bcm/pinctrl-iproc-gpio.c
> > > > +++ b/drivers/pinctrl/bcm/pinctrl-iproc-gpio.c
> > > > @@ -858,7 +858,7 @@ static int iproc_gpio_probe(struct platform_device *pdev)
> > > > struct gpio_irq_chip *girq;
> > > >
> > > > irqc = &chip->irqchip;
> > > > - irqc->name = "bcm-iproc-gpio";
> > > > + irqc->name = dev_name(dev);
> > > > irqc->irq_ack = iproc_gpio_irq_ack;
> > > > irqc->irq_mask = iproc_gpio_irq_mask;
> > > > irqc->irq_unmask = iproc_gpio_irq_unmask;
> > >
> > > Gr{oetje,eeting}s,
> > >
> > > Geert
> > >
> > > --
> > > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
> > >
> > > 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
> > >
>
>