On Tue, May 23, 2017 at 04:25:03PM -0700, Andrey Smirnov wrote: > On Mon, May 22, 2017 at 11:52 PM, Nikita Yushchenko > <nikita.yoush@xxxxxxxxxxxxxxxxxx> wrote: > >> + ret = of_property_read_u32(chip_np, "#gpio-cells", &gpio_cells); > >> + if (ret) > >> + return ret; > >> + > >> + if (WARN_ON(gpio_cells != 2)) > >> + return -ENOTSUPP; > >> + > >> + ret = of_property_read_u32_index(np, "gpios", idx * gpio_cells, > >> + &gpio_num); > >> + if (ret) > >> + return ret; > >> + > >> + ret = of_property_read_u32_index(np, "gpios", idx * gpio_cells + 1, > >> + &gpio_flags); > >> + if (ret) > >> + return ret; > > > > Doesn't this hardcode interpretation of device tree words in gpio > > specification - while this is intended to be gpio-provider specific and > > that's why #gpio-cells exist? > > > > It does and yes that's my understanding of the purpose of #gpio-cells > as well. The reason I did in such a primitive way was because > Barebox's GPIO subsystem doesn't have any translation plumbing to be > able to handle anything more than a simple one dimensional offset. > Given the fact that of_get_named_gpio_flags() make similar assumption > I thought that there are no real consumers of that functionality and > left proper implementation as a future improvement that can be made > once the need arises. > > > > >> +static int of_gpiochip_scan_gpios(struct gpio_chip *chip) > > > > Not best choice of name for routine that scans hogs? > > > > (although I understand that it comes from linux counterpart) > > > > Eh, I don't have any strong opinion on this one, I am more than happy > to rename it if you think there are better alternatives. > > >> - return 0; > >> + return of_gpiochip_scan_gpios(chip); > > > > Should we fail gpiochip registration on failure to claim hogs? > > I don't know. > > I couldn't think of a use-case where it wasn't basically all or > nothing: either I get everything working or I need to go back and fix > my DT. Sascha, do you have an opinion on this one? I can't think of any good reason why the hog initialization should fail and we still want to keep the gpio chip. Let's keep it like this until someone delivers us a good reason. Sasch -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox
