> -----Original Message----- > From: Linus Walleij <linus.walleij@xxxxxxxxxx> > Sent: 22 November 2019 17:58 > To: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx> > Cc: Yash Shah <yash.shah@xxxxxxxxxx>; robh+dt@xxxxxxxxxx; > mark.rutland@xxxxxxx; palmer@xxxxxxxxxxx; Paul Walmsley ( Sifive) > <paul.walmsley@xxxxxxxxxx>; aou@xxxxxxxxxxxxxxxxx; tglx@xxxxxxxxxxxxx; > jason@xxxxxxxxxxxxxx; maz@xxxxxxxxxx; bmeng.cn@xxxxxxxxx; > atish.patra@xxxxxxx; Sagar Kadam <sagar.kadam@xxxxxxxxxx>; linux- > gpio@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux- > riscv@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Sachin Ghadi > <sachin.ghadi@xxxxxxxxxx> > Subject: Re: [PATCH 3/4] gpio: sifive: Add GPIO driver for SiFive SoCs > > On Tue, Nov 19, 2019 at 5:42 PM Bartosz Golaszewski > <bgolaszewski@xxxxxxxxxxxx> wrote: > > wt., 19 lis 2019 o 16:03 Linus Walleij <linus.walleij@xxxxxxxxxx> napisał(a): > > > On Mon, Nov 18, 2019 at 11:15 AM Bartosz Golaszewski > > > <bgolaszewski@xxxxxxxxxxxx> wrote: > > > > > pon., 18 lis 2019 o 11:03 Yash Shah <yash.shah@xxxxxxxxxx> napisał(a): > > > Is it really so? The bgpio_lock does protect the registers used by > > > regmap-mmio but unless the interrupt code is also using the same > > > registers it is fine to have a different lock for those. > > > > > > Is the interrupt code really poking into the very same registers as > > > passed to bgpio_init()? > > > > > > Of course it could be seen as a bit dirty to poke around in the same > > > memory space with regmap and the bgpio_* accessors but in practice > > > it's no problem if they never touch the same things. > > > > > > Yours, > > > Linus Walleij > > > > I'm wondering if it won't cause any inconsistencies when for example > > interrupts are being triggered on input lines while we're also reading > > their values? Seems to me it's just more clear to use a single lock > > for a register range. Most drivers using gpio-mmio do just that in > > their irq-related routines. > > OK good point. Just one lock for the whole thing is likely more maintainable > even if it works with two different locks. > > > Anyway: even without using bgpio_lock this code is inconsistent: if > > we're using regmap for interrupt registers, we should either decide to > > rely on locking provided by regmap or disable it and use a locally > > defined lock. > > OK makes sense, let's say we use the bgpio_lock everywhere for this. > > Yash: are you OK with this? (Haven't read the new patch set yet, maybe it is > already fixed...) Yes, I am ok with this. I will be sending v3 soon with this change. - Yash
