dm: gpio: introduce 74x164 driver
Introduce driver to support "fairchild,74hc595" devices.
1. Take linux drivers/drivers/gpio/gpio-74x164.c as reference.
2. Following the naming used in Linux driver with gen_7x164 as the prefix.
3. Enable CONFIG_DM_74X164 to use this driver.
4. Follow Documentation/devicetree/bindings/gpio/gpio-74x164.txt to add device
nodes
5. Tested on i.MX6 UltraLite with 74LV595 using gpio command and oscillograph.
Signed-off-by: Peng Fan <van.freenix@gmail.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Chin Liang See <clsee@altera.com>
Cc: Bhuvanchandra DV <bhuvanchandra.dv@toradex.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Stefano Babic <sbabic@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 4b1f6b9..ddec1ef 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -12,6 +12,7 @@
obj-$(CONFIG_DM_GPIO) += gpio-uclass.o
obj-$(CONFIG_DM_PCA953X) += pca953x_gpio.o
+obj-$(CONFIG_DM_74X164) += 74x164_gpio.o
obj-$(CONFIG_AT91_GPIO) += at91_gpio.o
obj-$(CONFIG_ATMEL_PIO4) += atmel_pio4.o