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References: <20230511135632.78344-1-bstruempfel@ultratronik.de>
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From:   Fabio Estevam <festevam@gmail.com>
Date:   Thu, 11 May 2023 17:29:23 -0300
Message-ID: <CAOMZO5B_a-oauJFsO8aXwSxu-3_=YiYbsHi-B=2MykkJ08fNtA@mail.gmail.com>
Subject: Re: [PATCH] spi: Add option to keep the MOSI line low, when it is idle.
To:     Boerge Struempfel <boerge.struempfel@gmail.com>
Cc:     bstruempfel@ultratronik.de, Mark Brown <broonie@kernel.org>,
        Shawn Guo <shawnguo@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        NXP Linux Team <linux-imx@nxp.com>,
        linux-spi@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org,
        Schrempf Frieder <frieder.schrempf@kontron.de>
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Hi Boerge,

On Thu, May 11, 2023 at 10:58=E2=80=AFAM Boerge Struempfel
<boerge.struempfel@gmail.com> wrote:
>
> By default, the imx spi controller uses a high mosi line, whenever it is
> idle. This may not be desired in all use cases. For example neopixel
> leds can get confused and flicker due to misinterpreting the idle state.
> Therefore, we introduce a new spi-mode bit, with which the idle behaviour
> can be overwritten on a per device basis.
...
> +       if (of_property_read_bool(nc, "spi-mosi-idle-low"))
> +               spi->mode |=3D SPI_MOSI_IDLE_LOW;

Yes, this is useful.

As this is a new property,  please send a patch that adds it to:
Documentation/devicetree/bindings/spi/spi-peripheral-props.yaml

Thanks