Re: [PATCH v2] check: Add 10bit/slave i2c reg flags support

[Serge Semin]

On Sat, May 30, 2020 at 11:31:52AM +0200, Wolfram Sang wrote:
> 
> > +	addr = reg & 0x3FFFFFFFU;
> > +	snprintf(unit_addr, sizeof(unit_addr), "%x", addr);
> 
> Hmm, this hardcoded value will not work if we ever need to add another
> bit. I hope this will never happen, though.
> 
> > +		if ((reg & (1U << 31)) && addr > 0x3ff)
> 
> Same here with bit 31.

I'd be glad to use a macro or some helper here, but alas there is no
ready-to-use i2c-related one in the dtc code. See, there are hard-coded
literals in the PCI nodes checkers (check_pci_device_reg(),
check_pci_device_bus_num()) and the hard-coded literals've been in the
i2c-nodes checkers even before this patch.

> I haven't checked DTC but can't we import the
> header with the defines into the project? Or is this then a circular
> dependency?
> 

I guess importing header would be much better than the hard-coded values
currently used. What do the code maintainers say about that? Any idea how it
is supposed to be implemented?

-Sergey