Some electronics do not allow the data regsister to be read. Reading the register can corrupt the output. This makes it impossible to read the last data written to the port. The existing shadow data register 'bgpio_data' can be used to allow the last written value to be returned by the read operation in this scenario. This is enabled for a particular port using a new flag and a new device tree property. Signed-off-by: Niall Leonard <nl250060@xxxxxxx> --- Niall Leonard (3): gpio: dt-bindings: add new property to wd,mbl-gpio bindings gpio: Add new flag BGPIOF_NO_INPUT gpio: mmio: Use new flag BGPIOF_NO_INPUT .../devicetree/bindings/gpio/wd,mbl-gpio.txt | 1 + drivers/gpio/gpio-mmio.c | 19 +++++++++++++++++-- include/linux/gpio/driver.h | 1 + 3 files changed, 19 insertions(+), 2 deletions(-) --- base-commit: 1b929c02afd37871d5afb9d498426f83432e71c2 change-id: 20230126-gpio-mmio-fix-1a69d03ec9e7 Best regards, -- Niall Leonard <nl250060@xxxxxxx>