wt., 18 gru 2018 o 14:54 Janek Kotas <jank@xxxxxxxxxxx> napisał(a): > > > > On 18 Dec 2018, at 13:50, Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx> wrote: > > > > > > pon., 17 gru 2018 o 23:22 Linus Walleij <linus.walleij@xxxxxxxxxx> napisał(a): > >> > >> On Mon, Dec 17, 2018 at 4:51 PM Bartosz Golaszewski > >> <bgolaszewski@xxxxxxxxxxxx> wrote: > >> > >>> The driver looks good but is there any particular reason not to use > >>> regmap for register IO? > >> > >> I thought we only use regmap for MMIO when the register range is > >> shared (as in a system controller) so that some registers are for this, > >> some register or even bits in a register for some other driver, so they > >> need the spinlock in the regmap to protect the register range. > >> > > > > This is what syscon is for. Regmap simply abstracts any register IO. > > For instance: there's no locking in this driver. Are we sure it's not > > needed? Regmap provides internal locking for you in the form of a > > mutex or spinlock. > > > > Also: it looks like the interrupts here are quite simple with a single > > bit per interrupt in the status register and the same layout in the > > mask register - it could probably profit from using the > > regmap_irq_chip and not bother with reimplementing irq_chip callbacks. > > > >> It is also nice for shadowing/caching of register contents I guess, > >> wat does this driver get from regmap MMIO? > >> > > > > Code shrinkage IMO. > > > > Note that I'm not blocking this from being merged - I just think that > > using modern frameworks is always a good idea. > > I can reimplement the driver using regmap, but It seems in such case > I won’t be able to use the Generic GPIO Infrastructure, would I? > So I would need to provide functions for setting direction, etc. > I think it would make the driver code bigger. > Indeed. If anything: gpio-mmio would need to be converted to using regmap. So I guess nevermind my comment. Bart
