Re: [PATCH v3 1/4] dt-bindings: mfd: Add bindings for Ampere Altra SMPro drivers
From: Quan Nguyen
Date: Thu Apr 15 2021 - 08:34:01 EST
On 14/04/2021 15:28, Quan Nguyen wrote:
On 13/04/2021 20:49, Rob Herring wrote:
On Fri, Apr 09, 2021 at 10:13:29AM +0700, Quan Nguyen wrote:
Adds device tree bindings for SMPro drivers found on the Mt.Jade
hardware
reference platform with Ampere's Altra Processor family.
Signed-off-by: Quan Nguyen <quan@xxxxxxxxxxxxxxxxxxxxxx>
---
.../bindings/hwmon/ampere,ac01-hwmon.yaml | 28 +++++
.../devicetree/bindings/mfd/ampere,smpro.yaml | 105 ++++++++++++++++++
2 files changed, 133 insertions(+)
create mode 100644
Documentation/devicetree/bindings/hwmon/ampere,ac01-hwmon.yaml
create mode 100644
Documentation/devicetree/bindings/mfd/ampere,smpro.yaml
diff --git
a/Documentation/devicetree/bindings/hwmon/ampere,ac01-hwmon.yaml
b/Documentation/devicetree/bindings/hwmon/ampere,ac01-hwmon.yaml
new file mode 100644
index 000000000000..fbf7ec754160
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwmon/ampere,ac01-hwmon.yaml
@@ -0,0 +1,28 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/hwmon/ampere,ac01-hwmon.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Hardware monitoring driver for the Ampere Altra SMPro
+
+maintainers:
+ - Quan Nguyen <quan@xxxxxxxxxxxxxxxxxxxxxx>
+
+description: |
+ This module is part of the Ampere Altra SMPro multi-function
device. For more
+ details see ../mfd/ampere,smpro.yaml.
+
+properties:
+ compatible:
+ enum:
+ - ampere,ac01-hwmon
+
+ reg:
+ maxItems: 1
+
+required:
+ - compatible
+ - reg
+
+additionalProperties: false
diff --git a/Documentation/devicetree/bindings/mfd/ampere,smpro.yaml
b/Documentation/devicetree/bindings/mfd/ampere,smpro.yaml
new file mode 100644
index 000000000000..5613c420869e
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/ampere,smpro.yaml
@@ -0,0 +1,105 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mfd/ampere,smpro.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Ampere Altra SMPro firmware driver
+
+maintainers:
+ - Quan Nguyen <quan@xxxxxxxxxxxxxxxxxxxxxx>
+
+description: |
+ Ampere Altra SMPro firmware may contain different blocks like
hardware
+ monitoring, error monitoring and other miscellaneous features.
+
+properties:
+ compatible:
+ enum:
+ - ampere,smpro
Again, not very specific. There's only 1 version of 'smpro' h/w or
firmware? Are the firmware version and features discoverable? If not,
you need to be more specific (or better yet, make them discoverable).
Hi Rob,
So far, there's nothing to guarantee this is the only version of SMPro
and neither firmware version nor features that are discoverable.
In fact, it was "ampere,ac01-smpro" specifically in my v1. But this is
the "ampere,smpro" in arch/arm/boot/dts/nuvoton-npcm730-kudo.dts, that
is why it got changed to "ampere,smpro" to avoid changes in that dts file.
I'm thinking about change it back to "ampere,ac01-smpro" in next version
to make this compatible string more specific.
Hi Rob, I have a second thought on this.
What MFD SMPro driver does is only to expose the register map for child
drivers to use. Child drivers are capable to handle the specific details
among SMPro version if necessary. Hence, even though we address the
SMPro specific here (ie: by using specific compatible string),
eventually, regardless of any version the SMPro might be, the MFD SMPro
driver still just to expose the register map for its child drivers.
So, if that makes sense, I'd like to keep the "ampere,smpro" as
compatible string.
- Quan
+
+ reg:
+ description:
+ I2C device address.
+ maxItems: 1
+
+ "#address-cells":
+ const: 1
+
+ "#size-cells":
+ const: 0
+
+patternProperties:
+ "^hwmon(@[0-9a-f]+)?$":
+ $ref: ../hwmon/ampere,ac01-hwmon.yaml
+
+ "^misc(@[0-9a-f]+)?$":
You don't need these child nodes in DT if there are no resources
associated with them. The parent driver can instantiate all the
sub-functions.
From v3, there is a "reg" property introduced for the child driver,
especially for the misc driver. This is unavoidable because other
properties might be introduced in future for other misc features.
+ type: object
+ description: |
+ This module is part of the Ampere Altra SMPro multi-function
device
+ to support miscellaneous features
+ properties:
+ compatible:
+ enum:
+ - ampere,ac01-misc
+ reg:
+ maxItems: 1
+
+ required:
+ - compatible
+ - reg
+
+ "^errmon(@[0-9a-f]+)?$":
+ type: object
+ description: |
+ This module is part of the Ampere Altra SMPro multi-function
device
+ that supports error monitoring feature.
+
+ properties:
+ compatible:
+ enum:
+ - ampere,ac01-errmon
+ reg:
+ maxItems: 1
+
+ required:
+ - compatible
+ - reg
+
+required:
+ - "#address-cells"
+ - "#size-cells"
+ - compatible
+ - reg
+
+additionalProperties: false
+
+examples:
+ - |
+ i2c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ smpro@4f {
+ compatible = "ampere,smpro";
+ reg = <0x4f>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ hwmon@10 {
+ compatible = "ampere,ac01-hwmon";
+ reg = <0x10>;
+ };
+
+ misc@b0 {
+ compatible = "ampere,ac01-misc";
+ reg = <0xb0>;
+ };
+
+ errmon@80 {
+ compatible = "ampere,ac01-errmon";
+ reg = <0x80>;
+ };
+
+ };
+ };
--
2.28.0