Messages in this thread | | | Date | Thu, 2 May 2019 11:45:24 +0900 | From | Mark Brown <> | Subject | Re: [PATCH 0/3] spi: SPI bus multiplexer |
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On Sun, Apr 28, 2019 at 10:28:16PM +0000, Chris Packham wrote:
> One other problem that I encounter is the interaction between cs-gpio > and SPI_MASTER_GPIO_SS. Having cs-gpio automatically sets SPI_CS_HIGH > which has the undesired side-effect that now my real chip select is > inverted. I actually wonder if this change breaks commit 8eee6b9dd30d > ("spi: Add Flag to Enable Slave Select with GPIO Chip Select.") since > now there is an extra inversion on the CS enable.
That sounds like a framework bug which should just be fixed - we shouldn't be disrupting users of real chip selects when using a GPIO chip select. Depending on the hardware we might need a chip select assigned that isn't connected to anything for use while the GPIOs are doing the real work but otherwise we shouldn't be breaking things. [unhandled content-type:application/pgp-signature] | |