#
# GPIO infrastructure and drivers
#
config ARCH_HAVE_CUSTOM_GPIO_H
bool
help
Selecting this config option from the architecture Kconfig allows
the architecture to provide a custom asm/gpio.h implementation
overriding the default implementations. New uses of this are
strongly discouraged.
menuconfig GPIOLIB
bool "GPIO Support"
select ANON_INODES
help
This enables GPIO support through the generic GPIO library.
You only need to enable this, if you also want to enable
one or more of the GPIO drivers below.
If unsure, say N.
if GPIOLIB
config GPIOLIB_FASTPATH_LIMIT
int "Maximum number of GPIOs for fast path"
range 32 512
default 512
help
This adjusts the point at which certain APIs will switch from
using a stack allocated buffer to a dynamically allocated buffer.
You shouldn't need to change this unless you really need to
optimize either stack space or performance. Change this carefully
since setting an incorrect value could cause stack corruption.
config OF_GPIO
def_bool y
depends on OF
depends on HAS_IOMEM
config GPIO_ACPI
def_bool y
depends on ACPI
config GPIOLIB_IRQCHIP
select IRQ_DOMAIN
bool
config DEBUG_GPIO
bool "Debug GPIO calls"
depends on DEBUG_KERNEL
help
Say Y here to add some extra checks and diagnostics to GPIO calls.
These checks help ensure that GPIOs have been properly initialized
before they are used, and that sleeping calls are not made from
non-sleeping contexts. They can make bitbanged serial protocols
slower. The diagnostics help catch the type of setup errors
that are most common when setting up new platforms or boards.
config GPIO_SYSFS
bool "/sys/class/gpio/... (sysfs interface)"
depends on SYSFS
help
Say Y here to add a sysfs interface for GPIOs.
This is mostly useful to work around omissions in a system's
kernel support. Those are common in custom and semicustom
hardware assembled using standard kernels with a minimum of
custom patches. In those cases, userspace code may import
a given GPIO from the kernel, if no kernel driver requested it.
Kernel drivers may also request that a particular GPIO be
exported to userspace; this can be useful when debugging.
config GPIO_GENERIC
depends on HAS_IOMEM # Only for IOMEM drivers
tristate
# put drivers in the right section, in alphabetical order
# This symbol is selected by both I2C and SPI expanders
config GPIO_MAX730X
tristate
menu "Memory mapped GPIO drivers"
depends on HAS_IOMEM
config GPIO_74XX_MMIO
tristate "GPIO driver for 74xx-ICs with MMIO access"
depends on OF_GPIO
select GPIO_GENERIC
help
Say yes here to support GPIO functionality for 74xx-compatible ICs
with MMIO access. Compatible models include:
1 bit: 741G125 (Input), 741G74 (Output)
2 bits: 742G125 (Input), 7474 (Outp