On Mon, 4 Mar 2019 11:25:01 -0500 Sven Van Asbroeck <thesven73@xxxxxxxxx> wrote: > On Sun, Mar 3, 2019 at 9:38 AM Jonathan Cameron <jic23@xxxxxxxxxx> wrote: > > > > Hmm. Just been thinking a bit about the events on here and wondered > > if it is possible to mask them through careful use of the threshold > > values - i.e. can we stop the hardware generating the interrupts for > > the ones we don't want. It would be unusual for hardware to be > > designed where this wasn't possible. > > Excellent point! People with power / battery constraints take a dim view of > receiving interrupts when no-one wants them. So disabling them in h/w > is definitely the way to go, if possible. > > And yes, this also makes a non-issue of thresh_en visibility concerns, if any. > > > > > Alternatively if you have a scope or equivalent to verify if it is doing > > these as a multi byte read and working that would be even better. > > It is not uncommon for hardware to implement fairly standard i2c features > > like this and not document them because they weren't what the test code > > the docs writer got given does! (may not be true here of course) > > Or alternatively, the current chip rev supports undocumented multi-reads, > and the next revision silently drops support, thereby breaking the driver... > Been there, done that, got the T-shirt :( Indeed it's a risk. Sadly hardware guys never have a 'we mustn't break software' rule like we do for userspace! Jonathan
