Just a gentle reminder as this thread has been quiet for a while. Rob,
I would appreciate some feedback on my question from my previous email. 

To add a little more detail: I want to avoid simply checking for the
existence of a property in the DTS as that could break compatibility
with codebases implementing their own method of handling the attenuator
bypass.

On Thu, 2020-01-30 at 03:07 +0000, Logan Shaw wrote:

On Mon, 2020-01-27 at 09:48 -0600, Rob Herring wrote:

quoted

On Mon, Jan 27, 2020 at 11:10:14AM +1300, Logan Shaw wrote:

quoted

Added a new file documenting the adt7475 devicetree and added the
four
new properties to it.

Signed-off-by: Logan Shaw <redacted>
---
---
 .../devicetree/bindings/hwmon/adt7475.yaml    | 95
+++++++++++++++++++
 1 file changed, 95 insertions(+)
 create mode 100644
Documentation/devicetree/bindings/hwmon/adt7475.yaml

diff --git a/Documentation/devicetree/bindings/hwmon/adt7475.yaml

b/Documentation/devicetree/bindings/hwmon/adt7475.yaml
new file mode 100644
index 000000000000..450da5e66e07

--- /dev/null
+++ b/Documentation/devicetree/bindings/hwmon/adt7475.yaml

@@ -0,0 +1,95 @@
+# SPDX-License-Identifier: GPL-2.0

Dual license new bindings please:

(GPL-2.0-only OR BSD-2-Clause)

quoted

+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/adt7475.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ADT7475 hwmon sensor
+
+maintainers:
+  - Jean Delvare [off-list ref]
+
+description: |
+  The ADT7473, ADT7475, ADT7476, and ADT7490 are thermal
monitors
and multiple
+  PWN fan controllers.
+
+  They support monitoring and controlling up to four fans (the
ADT7490 can only
+  control up to three). They support reading a single on chip
temperature
+  sensor and two off chip temperature sensors (the ADT7490
additionally
+  supports measuring up to three current external temperature
sensors with
+  series resistance cancellation (SRC)).
+
+  Datasheets:
+  https://www.onsemi.com/pub/Collateral/ADT7473-D.PDF
+  https://www.onsemi.com/pub/Collateral/ADT7475-D.PDF
+  https://www.onsemi.com/pub/Collateral/ADT7476-D.PDF
+  https://www.onsemi.com/pub/Collateral/ADT7490-D.PDF
+
+  Description taken from omsemiconductors specification sheets,
with minor

omsemi?
 ^

quoted

+  rephrasing.
+
+properties:
+  compatible:
+    enum:
+      - adi,adt7473
+      - adi,adt7475
+      - adi,adt7476
+      - adi,adt7490
+
+  reg:
+    maxItems: 1
+
+  bypass-attenuator-in0:

Needs a vendor prefix and a type ref. 

quoted

+    description: |
+      Configures bypassing the individual voltage input
+      attenuator, on in0. This is supported on the ADT7476 and
ADT7490.
+      If set to a non-zero integer the attenuator is bypassed,
if
set to
+      zero the attenuator is not bypassed. If the property is
absent then
+      the config register is not modified.

Sounds like this could be boolean? If not, define a schema for what
are 
valid values.

By boolean are you referring to a dts property that is evaluated
(using
function of_property_read_bool) as true/false, depending on its
presence? For example "regulator-always-on" in:
/Documentation/devicetree/bindings/regulator/regulator.yaml .

quoted

quoted

+    maxItems: 1
+
+  bypass-attenuator-in1:
+    description: |
+      Configures bypassing the individual voltage input
+      attenuator, on in1. This is supported on the ADT7473,
ADT7475,
+      ADT7476 and ADT7490. If set to a non-zero integer the
attenuator
+      is bypassed, if set to zero the attenuator is not
bypassed.
If the
+      property is absent then the config register is not
modified.
+    maxItems: 1
+
+  bypass-attenuator-in3:
+    description: |
+      Configures bypassing the individual voltage input
+      attenuator, on in3. This is supported on the ADT7476 and
ADT7490.
+      If set to a non-zero integer the attenuator is bypassed,
if
set to
+      zero the attenuator is not bypassed. If the property is
absent then
+      the config register is not modified.
+    maxItems: 1
+
+  bypass-attenuator-in4:

These 4 could be a single entry under patternProperties.

quoted

+    description: |
+      Configures bypassing the individual voltage input
+      attenuator, on in4. This is supported on the ADT7476 and
ADT7490.
+      If set to a non-zero integer the attenuator is bypassed,
if
set to
+      zero the attenuator is not bypassed. If the property is
absent then
+      the config register is not modified.
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+examples:
+  - |
+    i2c {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      hwmon@2e {
+        compatible = "adi,adt7476";
+        reg = <0x2e>;
+        bypass-attenuator-in0 = <1>;
+        bypass-attenuator-in1 = <0>;
+      };
+    };
+...
-- 
2.25.0