Re: [RESEND PATCH] arm64: dts: tegra: Fix boolean properties with values

From: Jon Hunter
Date: Mon Apr 25 2022 - 07:20:35 EST



On 12/04/2022 10:05, Thierry Reding wrote:
On Wed, Apr 06, 2022 at 02:17:30PM -0500, Rob Herring wrote:
Boolean properties in DT are present or not present and don't take a value.
A property such as 'foo = <0>;' evaluated to true. IOW, the value doesn't
matter.

It may have been intended that 0 values are false, but there is no change
in behavior with this patch.

Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
---
Can someone apply this for 5.18.

arch/arm64/boot/dts/nvidia/tegra186-p3310.dtsi | 8 ++++----
.../boot/dts/nvidia/tegra186-p3509-0000+p3636-0001.dts | 8 ++++----
arch/arm64/boot/dts/nvidia/tegra194-p2888.dtsi | 6 +++---
arch/arm64/boot/dts/nvidia/tegra194-p3668.dtsi | 6 +++---
arch/arm64/boot/dts/nvidia/tegra210-p2180.dtsi | 6 +++---
arch/arm64/boot/dts/nvidia/tegra210-p2894.dtsi | 8 ++++----
arch/arm64/boot/dts/nvidia/tegra210-p3450-0000.dts | 8 ++++----
arch/arm64/boot/dts/nvidia/tegra210-smaug.dts | 4 ++--
8 files changed, 27 insertions(+), 27 deletions(-)

This causes multiple regressions on Tegra boards. The reason for this is
that these properties are not in fact boolean, despite what the DT
bindings say. If you look at the code that handles these, you'll notice
that they are single-cell properties, typically with <0> and <1> values.
What may have led to the conclusion that these are boolean is that there
is also a special case where these can be left out, but the meaning of
that is not the "false" (<0>) value. Instead, leaving these out means
that the values should be left at whatever is currently in the register.

See pinconf_generic_parse_dt_config() and parse_dt_cfg() specifically in
drivers/pinctrl/pinconf-generic.c.

Arnd, can you please revert this so that these boards can be unbroken?


Arnd, any feedback on this? A lot of Tegra boards are still not booting with v5.18-rc4.

Jon

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nvpublic