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Date:   Tue, 15 Feb 2022 22:14:24 +0100
From:   Andrew Lunn <andrew@lunn.ch>
To:     =?utf-8?B?UGF3ZcWC?= Dembicki <paweldembicki@gmail.com>
Cc:     Rob Herring <robh+dt@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
        Olof Johansson <olof@lixom.net>, soc@kernel.org,
        Gregory Clement <gregory.clement@bootlin.com>,
        Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>,
        Shawn Guo <shawnguo@kernel.org>,
        Sam Ravnborg <sam@ravnborg.org>,
        Linus Walleij <linus.walleij@linaro.org>,
        Corentin Labbe <clabbe@baylibre.com>,
        Oleksij Rempel <linux@rempel-privat.de>,
        Hao Fang <fanghao11@huawei.com>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>, linux-kernel@vger.kernel.org,
        Linux ARM <linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH v2 2/2] ARM: dts: kirkwood: Add Ctera C-200 V1 board
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> > Thanks for adding a comment. So you need something like a PWM driving
> > it? Have you tried playing with drivers/input/misc/pwm-beeper.c ?
> 
> It use a PWM device. Driver gpio-pwm isn't accepted in mainline so far.
> 
> > Some of the mvebu family have a simple PWM functionality as part of
> > the GPIO controller. I don't remember if kirkwood has this.
> 
> Kirkwood have very simple blink mode only: GPIO pin make visible blinks.

[Goes and looks at the datasheet]

Yes, Kirkwood has fixed rate blinking. It is the later generation of
devices which have true PWM capabilities.

	Andrew