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[0/3] Introduce new optional property to mark port as write only

Message ID 20230126-gpio-mmio-fix-v1-0-8a20ce0e8275@ncr.com
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Series Introduce new optional property to mark port as write only | expand

Message

Niall Leonard via B4 Submission Endpoint Jan. 26, 2023, 10:17 a.m. UTC
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@ncr.com>
---
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,