As evidenced by the Qualcomm TLMM Linux driver, the TLMM IP block in
Qualcomm SoCs has a bit to enable/disable the output for a pin that's
configured as a GPIO but _not_ a bit to enable/disable an input
buffer. Current device trees that are specifying "input-enable" for
pins managed by TLMM are either doing so needlessly or are using it to
mean "output-disable".
Presumably the current convention of using "input-enable" to mean
"output-disable" stems from the fact that "output-disable" is a "new"
property from 2017. It was introduced in commit 425562429d4f
("pinctrl: generic: Add output-enable property"). The "input-enable"
handling in Qualcomm drivers is from 2015 introduced in commit
407f5e392f9c ("pinctrl: qcom: handle input-enable pinconf property").
Given that there's no other use for "input-enable" for TLMM, we can
still handle old device trees in code, but let's encourage people to
move to the proper / documented property by updating the bindings.
Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
---
.../devicetree/bindings/pinctrl/qcom,tlmm-common.yaml | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/pinctrl/qcom,tlmm-common.yaml b/Documentation/devicetree/bindings/pinctrl/qcom,tlmm-common.yaml
index cb5ba1bd6f8d..5a815c199642 100644
--- a/Documentation/devicetree/bindings/pinctrl/qcom,tlmm-common.yaml
+++ b/Documentation/devicetree/bindings/pinctrl/qcom,tlmm-common.yaml
@@ -75,7 +75,8 @@ $defs:
bias-pull-down: true
bias-pull-up: true
bias-disable: true
- input-enable: true
+ input-enable: false
+ output-disable: true
output-high: true
output-low: true
--
2.40.0.348.gf938b09366-goog
