Boolean type properties are usually considered true if present and false
when they do not exist. This works well for many in-tree board dts and
existing drivers.
When users need to overrride boolean values from included dts,
/delete-property/ is recommend. This however does not work in overlays
(addons).
Geert pointed out [1] that there are several invitations for using
strings "true" and "false" on boolean properties: [1], [2], [3].
Add support for a string value "false" to be considered false on boolean
properties by changing of_property_read_bool implementation.
Affected by this issue is AM642 HummingBoard-T overlay to enable usb-3.1
function. This is an alternative solution to dropping
it's disfynctional overlay [1].
[1] https://lore.kernel.org/linux-devicetree/CAMuHMdWY0J7uooeRbUGwjkeCLd2UVyN9dtDWUkg5pJ3sAULdsQ@xxxxxxxxxxxxxx/
[2] Documentation/devicetree/bindings/sound/rt5651.txt
[3] Documentation/devicetree/bindings/sound/pcm3060.txt
[4] arch/arm/boot/dts/ti/omap/am335x-baltos.dtsi
[5] https://lore.kernel.org/linux-devicetree/20241101-am64-hb-fix-overlay-v1-1-080b98b057b6@xxxxxxxxxxxxx/
Reported-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Closes: https://lore.kernel.org/linux-devicetree/CAMuHMdXTgpTnJ9U7egC2XjFXXNZ5uiY1O+WxNd6LPJW5Rs5KTw@xxxxxxxxxxxxxx
Fixes: bbef42084cc1 ("arm64: dts: ti: hummingboard-t: add overlays for m.2 pci-e and usb-3")
Signed-off-by: Josua Mayer <josua@xxxxxxxxxxxxx>
Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Cc: Jon Nettleton <jon@xxxxxxxxxxxxx>
Cc: Yazan Shhady <yazan.shhady@xxxxxxxxxxxxx>
Cc: rabeeh@xxxxxxxxxxxxx
Signed-off-by: Josua Mayer <josua@xxxxxxxxxxxxx>
---
Josua Mayer (2):
of: add support for value "false" to of_property_read_bool
arm64: dts: ti: k3-am642-hummingboard-t-usb3: fix overlay boolean value
arch/arm64/boot/dts/ti/k3-am642-hummingboard-t-usb3.dtso | 2 +-
drivers/of/property.c | 2 +-
include/linux/of.h | 13 ++++++++-----
3 files changed, 10 insertions(+), 7 deletions(-)
---
base-commit: 9852d85ec9d492ebef56dc5f229416c925758edc
change-id: 20241112-am64-overlay-bool-60a35da933f7
Best regards,
--
Josua Mayer <josua@xxxxxxxxxxxxx>
