Hi Andrew,

On 27/10/23 1:36 am, Andrew Lunn wrote:

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-struct oa_tc6 *oa_tc6_init(struct spi_device *spi, bool prote)
+struct oa_tc6 *oa_tc6_init(struct spi_device *spi)

Was there a reason to have prote initially, and then remove it here?

The reason is, control communication uses "protect". But in the first
patch there was no dt used. Later in this patch, dt used for all the
configuration parameters and this also part of that. That's why removed
and moved this to dt configuration.

What's your opinion? shall I keep as it is like this? or remove the
protect in the first two patches and introduce in this patch?

It will actually depend on what goes into the DT binding. If using
protections costs very little, i would just hard code it on. Maybe you
can run some iperf tests and see if it makes a measurable difference.

How fast an SPI bus are you using on your development board? If you
have a 50Mbps SPI bus, it does not even matter, since the media
bandwidth is just 10Mbps.

Actually protection is only used for control communication to read/write 
registers. It is not used in data communication where ethernet frame 
transfer performed. So it doesn't hurt data traffic. But of course in 
between data communication I may perform some control transfer for 
register read/write but they are not big and will not affect the speed. 
In my development board I use 15MHz speed SPI bus.

As this is given as a configurable parameter in the OPEN Alliance 
specification, I have implemented it in the DT binding for user 
input/choice.

Best Regards,
Parthiban V

     Andrew