linux-kernel - Re: [PATCH 1/2] mfd: max14577: Fix IRQ handling after resume if this is not a wakeup source

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-id: <1398690896.12945.2.camel@AMDC1943>
Date:	Mon, 28 Apr 2014 15:14:56 +0200
From:	Krzysztof Kozlowski <k.kozlowski@...sung.com>
To:	Lee Jones <lee.jones@...aro.org>
Cc:	Samuel Ortiz <sameo@...ux.intel.com>,
	Sangbeom Kim <sbkim73@...sung.com>,
	linux-kernel@...r.kernel.org,
	Kyungmin Park <kyungmin.park@...sung.com>,
	Marek Szyprowski <m.szyprowski@...sung.com>,
	Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>
Subject: Re: [PATCH 1/2] mfd: max14577: Fix IRQ handling after resume if this
 is not a wakeup source

On pon, 2014-04-28 at 13:10 +0100, Lee Jones wrote:
> > During suspend the IRQ should be disabled even if this is not a wakeup
> > source. This is a proper way of fixing the IRQ handling issue during
> > resume (IRQ handler fails because I2C bus did not resume yet).
> > 
> > When device is suspended and max14577 interrupt is signaled the irq chip
> > will try to handle it regardless of wakeup source. Device could be woken
> > up by different IRQ but still the IRQ handler will try to read the
> > registers over I2C bus and fail because I2C bus won't be ready yet:
> > 	max14577 2-0025: Failed to read IRQ status: -5
> > 
> > Signed-off-by: Krzysztof Kozlowski <k.kozlowski@...sung.com>
> > ---
> >  drivers/mfd/max14577.c | 29 +++++++++++++----------------
> >  1 file changed, 13 insertions(+), 16 deletions(-)
> 
> It's pretty worrying that these two patches are so alike and they
> actually change different files. Is there any way we can unify more of
> the code?
> 
> Patch applied, thanks.

This whole problem happens also on other MAXIM devices on our boards so
actually the real issue could sit in I2C bus controller or S3C PM
suspend/resume code. This is however the easiest fix for now...

Thanks for applying the patches.

Best regards,
Krzysztof

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/