[cadence-spi] daisy chain

[Adrian Fiergolski <adrian.fiergolski@xxxxxxxxxxxxx>]

Hi,

I have a daisy chain of three ltc2634 slaves (iio/dac/ltc2632.c)
connected to a single chip select of the cadence-spi master. I have the
impression such a configuration is supported by none of those two
drivers. I could try to extend both, however, I haven't found any other
SPI driver, where I could find implementation inspiration. Is it
supported by kernel?

The documentation mentions only about the common 'daisy-chained-devices'
property (devicetree/bindings/common-properties.txt). However, in order
to try to implement it in the master driver, IMHO, the spi subsystem
would need to have a call 'no-operation' to other nodes on the
daisy-chain, which are not addressed by the given SPI access. Is there
any recommended approach to address this case?

Regards,

Adrian