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Date:   Thu, 31 Dec 2020 15:23:19 +0100
From:   Lukas Wunner <lukas@wunner.de>
To:     Bert Vermeulen <bert@biot.com>
Cc:     Mark Brown <broonie@kernel.org>, Rob Herring <robh+dt@kernel.org>,
        Birger Koblitz <mail@birger-koblitz.de>,
        linux-spi@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH RESEND v2 2/2] Add support for Realtek RTL838x/RTL839x
 SoC SPI controllers
Message-ID: <20201231142319.GA28104@wunner.de>
References: <20201229231904.2558916-1-bert@biot.com>
 <20201229231904.2558916-2-bert@biot.com>
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On Wed, Dec 30, 2020 at 12:19:04AM +0100, Bert Vermeulen wrote:
> +static inline void wait_ready(struct rtspi *rtspi)
> +{
> +	while (!(readl(REG(RTL8380_SPI_SFCSR)) & RTL8380_SPI_SFCSR_RDY))
> +		;
> +}

I'd suggest calling cpu_relax() in the loop's body.


> +	err = devm_spi_register_controller(&pdev->dev, ctrl);

Since you're invoking devm_spi_register_controller() on probe,
the controller must not be unregistered explicitly on remove.
So the ->remove hook can be dropped altogether:

> +static int realtek_spi_remove(struct platform_device *pdev)
> +{
> +	struct spi_controller *ctrl = platform_get_drvdata(pdev);
> +
> +	spi_unregister_controller(ctrl);
> +
> +	return 0;
> +}
[...]
> +	.remove = realtek_spi_remove,

The ->probe hook otherwise LGTM.

Thanks,

Lukas