gpio: Add support for Janz VMOD-TTL Digital IO module

The Janz VMOD-TTL is a MODULbus daughterboard which fits onto any MODULbus
carrier board. It essentially consists of some various logic and a Zilog
Z8536 CIO Counter/Timer and Parallel IO Unit.

The board must be physically configured with jumpers to enable a user to
drive output signals. I am only interested in outputs, so I have made this
driver as simple as possible. It only supports a very minimal subset of the
features provided by the Z8536 chip.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 56eb0c59c512..0e9c16b5bbce 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -325,4 +325,14 @@ config GPIO_UCB1400
           To compile this driver as a module, choose M here: the
           module will be called ucb1400_gpio.
 
+comment "MODULbus GPIO expanders:"
+
+config GPIO_JANZ_TTL
+        tristate "Janz VMOD-TTL Digital IO Module"
+        depends on MFD_JANZ_CMODIO
+        help
+          This enables support for the Janz VMOD-TTL Digital IO module.
+          This driver provides support for driving the pins in output
+          mode only. Input mode is not supported.
+
 endif