gpio: add support for 74x164 serial-in/parallel-out 8-bit shift register

Add support for generic 74x164 serial-in/parallel-out 8-bits shift
register.  This driver can be used as a GPIO output expander.

[akpm@linux-foundation.org: remove unused local `refresh']
Signed-off-by: Miguel Gaio <miguel.gaio@efixo.com>
Signed-off-by: Juhos Gabor <juhosg@openwrt.org>
Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index e47ef94be379..bc7b0fca6415 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -344,6 +344,14 @@ config GPIO_MC33880
           SPI driver for Freescale MC33880 high-side/low-side switch.
           This provides GPIO interface supporting inputs and outputs.
 
+config GPIO_74X164
+        tristate "74x164 serial-in/parallel-out 8-bits shift register"
+        depends on SPI_MASTER
+        help
+          Platform driver for 74x164 compatible serial-in/parallel-out
+          8-outputs shift registers. This driver can be used to provide access
+          to more gpio outputs.
+
 comment "AC97 GPIO expanders:"
 
 config GPIO_UCB1400