On Wed, Jul 20, 2016 at 3:28 PM, Andrew Jeffery <andrew@xxxxxxxx> wrote: > The Aspeed SoCs provide typically more than 200 pins for GPIO and other > functions. The signal enabled on a pin is determined on a priority > basis, where a given pin can provide a number of different signal types. > > In addition to the priority levels, the Aspeed pin controllers describe > the signal active on a pin by compound logical expressions involving > multiple operators, registers and bits. Some difficulty arises as a > pin's function bit masks for each priority level are frequently not the > same (i.e. we cannot just flip a bit to change from a high to low > priority signal), or even in the same register(s). Some configuration > bits affect multiple pins, while in other cases the signals for a bus > must each be enabled individually. > > Together, these features give rise to some complexity in the > implementation. A more complete description of the complexities is > provided in the associated header file in an attempt to justify the > approach. > > Note that the patch doesn't implement pinctrl/pinmux/pinconf for any > particular SoC, just adds the framework for defining mux configurations > for any available functions. > > Signed-off-by: Andrew Jeffery <andrew@xxxxxxxx> Reviewed-by: Joel Stanley <joel@xxxxxxxxx> > --- > MAINTAINERS | 1 + > arch/arm/mach-aspeed/Kconfig | 1 + > drivers/pinctrl/Kconfig | 1 + > drivers/pinctrl/Makefile | 1 + > drivers/pinctrl/aspeed/Kconfig | 8 + > drivers/pinctrl/aspeed/Makefile | 3 + > drivers/pinctrl/aspeed/pinctrl-aspeed.c | 373 +++++++++++++++++++++ > drivers/pinctrl/aspeed/pinctrl-aspeed.h | 562 ++++++++++++++++++++++++++++++++ > 8 files changed, 950 insertions(+) > create mode 100644 drivers/pinctrl/aspeed/Kconfig > create mode 100644 drivers/pinctrl/aspeed/Makefile > create mode 100644 drivers/pinctrl/aspeed/pinctrl-aspeed.c > create mode 100644 drivers/pinctrl/aspeed/pinctrl-aspeed.h -- 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
