gpio: Add GPIO support for the ACCES 104-DIO-48E

The ACCES 104-DIO-48E device provides 48 lines digital I/O via two
Programmable Peripheral Interface (PPI) chips of type 82C55. Bit C3 at
each 24-bit Group can be used as an external interrupt, triggered by a
rising edge.

This driver provides GPIO and IRQ support for these 48 channels of
digital I/O. The base port address for the device may be configured via
the dio_48e_base module parameter. The interrupt line number for the
device may be configured via the dio_48e_irq module parameter.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

MAINTAINERS

@@ -240,6 +240,12 @@ L:	lm-sensors@lm-sensors.org
 S:	Maintained
 F:	drivers/hwmon/abituguru3.c
 
+ACCES 104-DIO-48E GPIO DRIVER
+M:	William Breathitt Gray <vilhelm.gray@gmail.com>
+L:	linux-gpio@vger.kernel.org
+S:	Maintained
+F:	drivers/gpio/gpio-104-dio-48e.c
+
 ACCES 104-IDI-48 GPIO DRIVER
 M:	"William Breathitt Gray" <vilhelm.gray@gmail.com>
 L:	linux-gpio@vger.kernel.org

drivers/gpio/Kconfig

@@ -487,6 +487,15 @@ endmenu
 menu "Port-mapped I/O GPIO drivers"
 	depends on X86 # Unconditional I/O space access
 
+config GPIO_104_DIO_48E
+	tristate "ACCES 104-DIO-48E GPIO support"
+	select GPIOLIB_IRQCHIP
+	help
+	  Enables GPIO support for the ACCES 104-DIO-48E family. The base port
+	  address for the device may be configured via the dio_48e_base module
+	  parameter. The interrupt line number for the device may be configured
+	  via the dio_48e_irq module parameter.
+
 config GPIO_104_IDIO_16
 	tristate "ACCES 104-IDIO-16 GPIO support"
 	select GPIOLIB_IRQCHIP

drivers/gpio/Makefile

@@ -12,6 +12,7 @@ obj-$(CONFIG_GPIO_ACPI)		+= gpiolib-acpi.o
 # Device drivers. Generally keep list sorted alphabetically
 obj-$(CONFIG_GPIO_GENERIC)	+= gpio-generic.o
 
+obj-$(CONFIG_GPIO_104_DIO_48E)	+= gpio-104-dio-48e.o
 obj-$(CONFIG_GPIO_104_IDIO_16)	+= gpio-104-idio-16.o
 obj-$(CONFIG_GPIO_104_IDI_48)	+= gpio-104-idi-48.o
 obj-$(CONFIG_GPIO_74X164)	+= gpio-74x164.o