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Date:   Wed, 9 Dec 2020 20:25:52 +0000
From:   Mark Brown <broonie@kernel.org>
To:     Serge Semin <fancer.lancer@gmail.com>
Cc:     Tudor Ambarus <tudor.ambarus@microchip.com>,
        linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] spi: Limit the spi device max speed to controller's max
 speed
Message-ID: <20201209202552.GE4790@sirena.org.uk>
References: <20201209173514.93328-1-tudor.ambarus@microchip.com>
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On Wed, Dec 09, 2020 at 11:15:35PM +0300, Serge Semin wrote:
> On Wed, Dec 09, 2020 at 07:54:20PM +0000, Mark Brown wrote:

> > Right, in general we aim to do this sort of fixup on the transfers
> > and messages rather than the devices, I guess we might be missing
> > validation in some of the flash acceleration paths or was this an issue
> > seen through inspection?

> In case of DW SPI driver we just make sure the SPI-client device
> speed set in the max_speed_hz doesn't exceed the controller SPI-bus
> clock frequency and clamp it if it does. So the driver is safe in that
> matter.

Ideally the driver wouldn't have to check though (no harm in doing so of
course).

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