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Message-ID: <0608e366-1b0e-d387-569a-9ed123bc4d69@ti.com>
Date:   Fri, 5 May 2023 14:46:10 +0530
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Subject: Re: [PATCH] spi: lpspi: disable lpspi module irq in DMA mode
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To:     Clark Wang <xiaoning.wang@nxp.com>, <broonie@kernel.org>
CC:     <linux-spi@vger.kernel.org>, <linux-kernel@vger.kernel.org>
References: <20230505063557.3962220-1-xiaoning.wang@nxp.com>
From:   Dhruva Gole <d-gole@ti.com>
In-Reply-To: <20230505063557.3962220-1-xiaoning.wang@nxp.com>
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On 05/05/23 12:05, Clark Wang wrote:
> When all bits of IER are set to 0, we still can observe the lpspi irq events
> when using DMA mode to transfer data.
> 
> So disable irq to avoid the too much irq events.
> 
> Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
> ---
>   drivers/spi/spi-fsl-lpspi.c | 7 ++++++-
>   1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c
> index f2341ab99556..4b70038ceb6b 100644
> --- a/drivers/spi/spi-fsl-lpspi.c
> +++ b/drivers/spi/spi-fsl-lpspi.c
> @@ -910,9 +910,14 @@ static int fsl_lpspi_probe(struct platform_device *pdev)
>   	ret = fsl_lpspi_dma_init(&pdev->dev, fsl_lpspi, controller);
>   	if (ret == -EPROBE_DEFER)
>   		goto out_pm_get;
> -

Any reason to delete this line?

>   	if (ret < 0)
>   		dev_err(&pdev->dev, "dma setup error %d, use pio\n", ret);
> +	else
> +		/*
> +		 * disable LPSPI module IRQ when enable DMA mode successfully,
> +		 * to prevent the unexpected LPSPI module IRQ events.
> +		 */
> +		disable_irq(irq);

Just wondering, have you actually seen any unexpected LPSPI module IRQ
events? If this was causing issues earlier then maybe add a fixes tag?

>   
>   	ret = devm_spi_register_controller(&pdev->dev, controller);
>   	if (ret < 0) {

-- 
Thanks and Regards,
Dhruva Gole