Hi, On Mon, 2014-02-10 at 12:29 -0800, Courtney Cavin wrote: > On Mon, Feb 10, 2014 at 08:41:44PM +0100, Ivan T. Ivanov wrote: > > > > Hi, > > > > On Mon, 2014-02-10 at 11:47 -0600, Andy Gross wrote: > > > On Mon, Feb 10, 2014 at 06:55:02PM +0200, Ivan T. Ivanov wrote: > > > > > > [....] > > > > > > > > > > Bail here? > > > > > > > > > > > > I don't know. What will be the consequences if controller continue to > > > > > > operate on its default rate? > > > > > > > > > > > > > > > > It is unclear. But if you can't set the rate that is configured or if there is > > > > > a misconfiguration, it's probably better to exit the probe and catch it here. > > > > > > > > > > > > My preference is to delay clock speed change till first > > > > SPI transfer. And use wherever transfer itself mandate. > > > > > > > > > > That works. My only concern is that it might be nice to catch a configuration > > > problem early rather than wait for the SPI transfer to fail continuously. > > > > If developer is skilled enough to know which version controller is, > > (s)he will be able to put the right frequency constrain here :-) > > A developer doesn't have to have much skill at all to copy-paste DT > configurations around and muck with numbers.... I agree with Andy here, > early validation is a good idea here, at the very least, some sanity > checks. Actually, thinking more on this. Supplying SPI controller with, let say 50MHz, which is what success of clk_set_rate() means, doesn't necessarily guaranteer that controller will be able to do transfers properly, right? Setting frequency at this point didn't bring any benefit. Regards, Ivan > > -Courtney -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
