From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [RFC 4/4] gpio: sifive: Add GPIO driver for SiFive SoCs
Date: Wed, 10 Oct 2018 06:12:55 -0700
Message-ID: <20181010131255.GB29142@infradead.org>
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 <mvmo9c22bx2.fsf@suse.de>
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To: Andreas Schwab <schwab@suse.de>
Cc: Atish Patra <atish.patra@wdc.com>, palmer@sifive.com, linux-riscv@lists.infradead.org, linux-pwm@vger.kernel.org, linux-gpio@vger.kernel.org, linus.walleij@linaro.org, robh+dt@kernel.org, thierry.reding@gmail.com, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, mark.rutland@arm.com, hch@infradead.org
List-Id: linux-pwm@vger.kernel.org

On Wed, Oct 10, 2018 at 03:01:29PM +0200, Andreas Schwab wrote:
> On Okt 09 2018, Atish Patra <atish.patra@wdc.com> wrote:
> 
> > +static void sifive_set_ie(struct sifive_gpio *chip, unsigned int offset)
> > +{
> > +	unsigned long flags;
> > +	unsigned int trigger;
> > +
> > +	raw_spin_lock_irqsave(&chip->lock, flags);
> > +	trigger = (chip->enabled & BIT(offset)) ? chip->trigger[offset] : 0;
> 
> This should use test_bit instead.

Given that this apparently needs the spinlock for atomciy with more than
just the bitmap test_bit would be rather pointless.