Re: [PATCH v2 2/2] mfd: atmel-flexcom: use resume_noirq

From: Lee Jones <lee.jones@linaro.org>
To: Claudiu Beznea <claudiu.beznea@microchip.com>
Cc: nicolas.ferre@microchip.com, alexandre.belloni@bootlin.com,
	ludovic.desroches@microchip.com, romain.izard.pro@gmail.com,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org,
	Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Subject: Re: [PATCH v2 2/2] mfd: atmel-flexcom: use resume_noirq
Date: Mon, 10 Jan 2022 15:38:12 +0000	[thread overview]
Message-ID: <YdxS5NaIWLviZUc0@google.com> (raw)
In-Reply-To: <20211028135138.3481166-3-claudiu.beznea@microchip.com>

On Thu, 28 Oct 2021, Claudiu Beznea wrote:

> Flexcom IP embeds 3 other IPs: usart, i2c, spi and selects the operation
> mode (usart, i2c, spi) via mode register (FLEX_MR). On i2c bus there might
> be connected critical devices (like PMIC) which on suspend/resume should
> be suspended/resumed at the end/beginning. i2c uses
> .suspend_noirq/.resume_noirq for this kind of purposes. Align flexcom
> to use .resume_noirq as it should be resumed before the embedded IPs.
> Otherwise the embedded devices might behave badly.
> 
> Fixes: 7fdec11015c3 ("atmel_flexcom: Support resuming after a chip reset")
> Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
> Tested-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
> Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
> ---
>  drivers/mfd/atmel-flexcom.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/mfd/atmel-flexcom.c b/drivers/mfd/atmel-flexcom.c
> index 962f66dc8813..559eb4d352b6 100644
> --- a/drivers/mfd/atmel-flexcom.c
> +++ b/drivers/mfd/atmel-flexcom.c
> @@ -87,7 +87,7 @@ static const struct of_device_id atmel_flexcom_of_match[] = {
>  };
>  MODULE_DEVICE_TABLE(of, atmel_flexcom_of_match);
>  
> -static int __maybe_unused atmel_flexcom_resume(struct device *dev)
> +static int __maybe_unused atmel_flexcom_resume_noirq(struct device *dev)
>  {
>  	struct atmel_flexcom *ddata = dev_get_drvdata(dev);
>  	int err;
> @@ -105,8 +105,9 @@ static int __maybe_unused atmel_flexcom_resume(struct device *dev)
>  	return 0;
>  }
>  
> -static SIMPLE_DEV_PM_OPS(atmel_flexcom_pm_ops, NULL,
> -			 atmel_flexcom_resume);
> +static const struct dev_pm_ops atmel_flexcom_pm_ops = {
> +	.resume_noirq = atmel_flexcom_resume_noirq,

Doesn't this mean you can remove __maybe_unused?

> +};
>  
>  static struct platform_driver atmel_flexcom_driver = {
>  	.probe	= atmel_flexcom_probe,

-- 
Lee Jones [李琼斯]
Principal Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
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