Hi Rafał, On Mon, Dec 8, 2014 at 3:27 PM, Rafał Miłecki <zajec5@xxxxxxxxx> wrote: > SN54HC595 and SN74HC595 are devices based on shift registers controlled > with 5 input signals (serial-in) and providing 8 outputs (parallel-out). > > They are present on some Broadcom home router boards where manufacturer > needed few extra GPIOs. > > This driver simply uses specified GPIOs to control shift registers and > registers another GPIO chip. So you can call it a GPIO extender. > > Due to the hardware design only output direction is supported. Reading > values is handled using tiny internal cache. > > Signed-off-by: Rafał Miłecki <zajec5@xxxxxxxxx> > --- > .../devicetree/bindings/gpio/gpio-sn54hc595.txt | 35 ++++ > drivers/gpio/Kconfig | 11 ++ > drivers/gpio/Makefile | 1 + > drivers/gpio/gpio-sn54hc595.c | 219 +++++++++++++++++++++ The '595 is already handled by drivers/gpio/gpio-74x164.c. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- 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