On Sun, 12 Jan 2025 20:50:41 +0200 Andy Shevchenko <andy.shevchenko@xxxxxxxxx> wrote: > On Sun, Jan 12, 2025 at 6:21 PM Javier Carrasco > <javier.carrasco.cruz@xxxxxxxxx> wrote: > > On Sun Jan 12, 2025 at 5:11 PM CET, Andy Shevchenko wrote: > > > On Sun, Jan 12, 2025 at 6:07 PM Javier Carrasco > > > <javier.carrasco.cruz@xxxxxxxxx> wrote: > > > > On Sun Jan 12, 2025 at 4:18 PM CET, Andy Shevchenko wrote: > > > > > Tue, Dec 24, 2024 at 11:59:02AM +0100, Javier Carrasco kirjoitti: > > > > > > The configuration and ID registers are not volatile and are not affected > > > > > > by read operations (i.e. not precious), making them suitable to be > > > > > > cached in order to reduce the number of accesses to the device. > > ... > > > > > > > + .cache_type = REGCACHE_RBTREE, > > > > > > > > > > Any specific reason why this is NOT a maple tree? > > > > > > > > I followed the most common approach in IIO (52 RBTREE vs 2 MAPLE), > > > > > > But it's historical and can't be taken as an argument. > > > > > > > assuming that the "low-end systems" comment for the different REGCACHE_* > > > > applies well to the typical systems that will make use of this driver, > > > > and many others under IIO. I considered that *possible* performance > > > > advantage for low-end systems above other considerations, like the > > > > general rule about using maple tree. > > > > > > https://elixir.bootlin.com/linux/v6.13-rc3/source/include/linux/regmap.h#L58 > > > > > > "Any new caches > > > * should usually use the maple tree cache unless they specifically > > > * require that there are never any allocations at runtime and can't > > > * provide defaults in which case they should use the flat cache." > > > > > > Can you reconsider? > > > > That was exactly the comment I referenced, actually the part about > > low-end systems that appears right after what you highlighted. > > > > I have nothing against switching to MAPLE, if that is preferred even if > > the main user of this driver will be a low-end system. I think that IIO > > is a typical subsystem that addresses needs for very low-end systems > > that are sometimes slightly more powerful than a microcontroller, but on > > the other hand I am by no means an expert, and if MAPLE is the way to go > > here as well, I will send a follow-up patch for it. > > Ah, I see now. Okay, I leave it then to Jonathan as I am okay with any > choice as long as it's understood and justified. For a fairly small regmap, I doubt there is a strong reason to care about the choice. So stick to what you have. For future drivers we can reassess as makes sense. Jonathan > >
