[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20201221184542.GA342038@robh.at.kernel.org>
Date: Mon, 21 Dec 2020 11:45:42 -0700
From: Rob Herring <robh@...nel.org>
To: Krzysztof Kozlowski <krzk@...nel.org>
Cc: Andy Gross <agross@...nel.org>,
Michael Turquette <mturquette@...libre.com>,
linux-kernel@...r.kernel.org, Angus Ainslie <angus@...ea.ca>,
Chanwoo Choi <cw00.choi@...sung.com>,
Bjorn Andersson <bjorn.andersson@...aro.org>,
Rob Herring <robh+dt@...nel.org>,
Matheus Castello <matheus@...tello.eng.br>,
linux-arm-kernel@...ts.infradead.org,
Mark Brown <broonie@...nel.org>,
Iskren Chernev <iskren.chernev@...il.com>,
Hans de Goede <hdegoede@...hat.com>,
Alessandro Zummo <a.zummo@...ertech.it>,
linux-clk@...r.kernel.org, linux-pm@...r.kernel.org,
linux-arm-msm@...r.kernel.org,
Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>,
linux-rtc@...r.kernel.org,
Alexandre Belloni <alexandre.belloni@...tlin.com>,
Lee Jones <lee.jones@...aro.org>,
Sebastian Reichel <sre@...nel.org>, devicetree@...r.kernel.org,
Liam Girdwood <lgirdwood@...il.com>,
linux-samsung-soc@...r.kernel.org,
Sebastian Krzyszkowiak <sebastian.krzyszkowiak@...i.sm>,
Stephen Boyd <sboyd@...nel.org>
Subject: Re: [RFC 13/18] mfd: max77686: Do not enforce (incorrect) interrupt
trigger type
On Thu, 10 Dec 2020 22:25:29 +0100, Krzysztof Kozlowski wrote:
> Interrupt line can be configured on different hardware in different way,
> even inverted. Therefore driver should not enforce specific trigger
> type - edge falling - but instead rely on Devicetree to configure it.
>
> The Maxim 77686 datasheet describes the interrupt line as active low
> with a requirement of acknowledge from the CPU therefore the edge
> falling is not correct.
>
> The interrupt line is shared between PMIC and RTC driver, so using level
> sensitive interrupt is here especially important to avoid races. With
> an edge configuration in case if first PMIC signals interrupt followed
> shortly after by the RTC, the interrupt might not be yet cleared/acked
> thus the second one would not be noticed.
>
> Signed-off-by: Krzysztof Kozlowski <krzk@...nel.org>
>
> ---
>
> This patch should wait till DTS changes are merged, as it relies on
> proper Devicetree.
> ---
> Documentation/devicetree/bindings/clock/maxim,max77686.txt | 4 ++--
> Documentation/devicetree/bindings/mfd/max77686.txt | 2 +-
> Documentation/devicetree/bindings/regulator/max77686.txt | 2 +-
> drivers/mfd/max77686.c | 3 +--
> 4 files changed, 5 insertions(+), 6 deletions(-)
>
Acked-by: Rob Herring <robh@...nel.org>
Powered by blists - more mailing lists