Re: [PATCH 2/3] dt: bindings: add ralink RT2880 resets device tree binding documentation

Hi Rob,

On Mon, Oct 4, 2021 at 8:06 PM Rob Herring [off-list ref] wrote:

On Sun, Sep 26, 2021 at 04:59:30PM +0200, Sergio Paracuellos wrote:

quoted

Adds device tree binding documentation for resets in the ralink RT2880 SoCs.

Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
---
 .../bindings/reset/ralink,rt2880-reset.yaml   | 39 +++++++++++++++++++
 1 file changed, 39 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/reset/ralink,rt2880-reset.yaml

diff --git a/Documentation/devicetree/bindings/reset/ralink,rt2880-reset.yaml b/Documentation/devicetree/bindings/reset/ralink,rt2880-reset.yaml
new file mode 100644
index 000000000000..88eddeb4ee45
--- /dev/null
+++ b/Documentation/devicetree/bindings/reset/ralink,rt2880-reset.yaml

@@ -0,0 +1,39 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/reset/ralink,rt2880-reset.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Ralink RT2880 Reset Controller Device Tree Bindings
+
+maintainers:
+  - Sergio Paracuellos <sergio.paracuellos@gmail.com>
+
+description: |
+  Ralink RT2880 reset controller driver which supports the SoC
+  system controller supplied reset registers for the various peripherals
+  of the SoC.
+
+  See also:
+  - dt-bindings/reset/ralink-rt2880.h
+
+properties:
+  compatible:
+    const: ralink,rt2880-reset
+
+  '#reset-cells':
+    const: 1
+
+required:
+  - '#reset-cells'
+  - compatible
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/reset/ralink-rt2880.h>
+    rstctrl: reset-controller {
+      compatible = "ralink,rt2880-reset";
+      #reset-cells = <1>;

How is this h/w controlled? If this is part of a system controller, then
it needs to be documented as such. IOW, you need to document the binding
for the whole block.

Do you really need a child node here? All you need to make a system
controller a reset provider is add '#reset-cells' to it.

I am just documenting what is already mainlined (see [0]) in order to
get mt7621-dts out of staging at some point of my life. What am I
supposed to do? Should I rewrite all already mainlined code? Because
if that is the case we need to rewrite tons of things from the ralink
platform...

I'd also like to know what we should do with those nodes already added
to the dtsi file that have not got associated compatible driver
mainlined. Can we just get rid of them?

Thanks in advance for clarification.

Best regards,
    Sergio Paracuellos

[0]: https://elixir.bootlin.com/linux/latest/source/arch/mips/ralink/reset.c

Rob