gpio: max732x driver

This adds a driver supporting a family of I2C port expanders from Maxim,
which includes the MAX7319 and MAX7320-7327 chips.

[dbrownell@users.sourceforge.net: minor fixes]
Signed-off-by: Jack Ren <jack.ren@marvell.com>
Signed-off-by: Eric Miao <eric.miao@marvell.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/gpio/Kconfig

@@ -67,6 +67,25 @@ config GPIO_SYSFS
 
 comment "I2C GPIO expanders:"
 
+config GPIO_MAX732X
+	tristate "MAX7319, MAX7320-7327 I2C Port Expanders"
+	depends on I2C
+	help
+	  Say yes here to support the MAX7319, MAX7320-7327 series of I2C
+	  Port Expanders. Each IO port on these chips has a fixed role of
+	  Input (designated by 'I'), Push-Pull Output ('O'), or Open-Drain
+	  Input and Output (designed by 'P'). The combinations are listed
+	  below:
+
+	  8 bits:	max7319 (8I), max7320 (8O), max7321 (8P),
+		  	max7322 (4I4O), max7323 (4P4O)
+
+	  16 bits:	max7324 (8I8O), max7325 (8P8O),
+		  	max7326 (4I12O), max7327 (4P12O)
+
+	  Board setup code must specify the model to use, and the start
+	  number for these GPIOs.
+
 config GPIO_PCA953X
 	tristate "PCA953x, PCA955x, and MAX7310 I/O ports"
 	depends on I2C

drivers/gpio/Makefile

@@ -5,6 +5,7 @@ ccflags-$(CONFIG_DEBUG_GPIO)	+= -DDEBUG
 obj-$(CONFIG_GPIOLIB)		+= gpiolib.o
 
 obj-$(CONFIG_GPIO_MAX7301)	+= max7301.o
+obj-$(CONFIG_GPIO_MAX732X)	+= max732x.o
 obj-$(CONFIG_GPIO_MCP23S08)	+= mcp23s08.o
 obj-$(CONFIG_GPIO_PCA953X)	+= pca953x.o
 obj-$(CONFIG_GPIO_PCF857X)	+= pcf857x.o