From: Krzysztof Kozlowski <redacted>
Date: Mon, 10 May 2021 09:03:13 -0400

On 08/05/2021 10:19, Mark Kettenis wrote:

quoted

The Apple GPIO controller is a simple combined pin and GPIO conroller
present on Apple ARM SoC platforms, including various iPhone and iPad
devices and the "Apple Silicon" Macs.

Signed-off-by: Mark Kettenis <redacted>
---
 .../bindings/pinctrl/apple,pinctrl.yaml       | 103 ++++++++++++++++++
 MAINTAINERS                                   |   2 +
 include/dt-bindings/pinctrl/apple.h           |  13 +++
 3 files changed, 118 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pinctrl/apple,pinctrl.yaml
 create mode 100644 include/dt-bindings/pinctrl/apple.h

diff --git a/Documentation/devicetree/bindings/pinctrl/apple,pinctrl.yaml b/Documentation/devicetree/bindings/pinctrl/apple,pinctrl.yaml
new file mode 100644
index 000000000000..cc7805ca6ba1
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/apple,pinctrl.yaml

@@ -0,0 +1,103 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pinctrl/apple,pinctrl.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Apple GPIO controller
+
+maintainers:
+  - Mark Kettenis <kettenis@openbsd.org>
+
+description: |
+  The Apple GPIO controller is a simple combined pin and GPIO conroller
+  present on Apple ARM SoC platforms, including various iPhone and iPad
+  devices and the "Apple Silicon" Macs.
+
+properties:
+  compatible:
+    items:
+      - const: apple,t8103-pinctrl
+      - const: apple,pinctrl

What is the point of having very generic final compatible in the binding
which does not relate to actual hardware?

Let's say next SoC will be
apple,x-abcd-foo-2323-whatever-nothing-in-common and you still have to
use generic "apple,pinctrl" even though HW is not at all compatible?
This looks like wildcard, not HW description.

Hi Krzysztof,

See my reply to Rob's mail.  We have some confidence that Apple isn't
changing their GPIO block very often.  If they were to change it in an
incompatible way in a future SoC, we'd drop the "apple,pinctrl"
compatible of course.

Thanks,

Mark