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Date:   Fri, 16 Jun 2023 18:15:35 +0200
From:   Miquel Raynal <miquel.raynal@bootlin.com>
To:     Mark Brown <broonie@kernel.org>
Cc:     Tudor Ambarus <tudor.ambarus@linaro.org>,
        linux-spi@vger.kernel.org,
        Nicolas Ferre <nicolas.ferre@microchip.com>,
        Alexandre Belloni <alexandre.belloni@bootlin.com>,
        Claudiu Beznea <claudiu.beznea@microchip.com>,
        linux-arm-kernel@lists.infradead.org,
        Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Subject: Re: [PATCH] spi: atmel: Prevent false timeouts on long transfers
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Hi Mark,

broonie@kernel.org wrote on Fri, 16 Jun 2023 15:20:27 +0100:

> On Fri, Jun 16, 2023 at 04:12:25PM +0200, Miquel Raynal wrote:
>=20
> > -#define SPI_DMA_TIMEOUT		(msecs_to_jiffies(1000))
> > +#define SPI_DMA_MIN_TIMEOUT	(msecs_to_jiffies(1000))
> > +#define SPI_DMA_TIMEOUT_PER_10K	(msecs_to_jiffies(4)) =20
>=20
> Given that we know the bus speed can't we just calculate this like other
> drivers do (we should probably add a helper TBH)?

I agree we should probably have some kind of easy-to-use helper to
derive a decent timeout value. How do sound the heuristics
proposed here to you ? That would be:

	timeout =3D 1s + 4ms/10k

Thanks,
Miqu=C3=A8l