Hi Andrew, On 27/10/23 1:36 am, Andrew Lunn wrote: > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > >>>> -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
