Re: [PATCH 01/16] dt-bindings: net: dwmac: Add DW GMAC GPIOs properties

Synopsys DesignWare Ethernet controllers can be synthesized with
General-Purpose IOs support. GPIOs can work either as inputs or as outputs
thus belong to the gpi_i and gpo_o ports respectively. The ports width
(number of possible inputs/outputs) and the configuration registers layout
depend on the IP-core version. For instance, DW GMAC can have from 0 to 4
GPIs and from 0 to 4 GPOs, while DW xGMAC have a wider ports width up to
16 pins of each one.

So the DW MAC DT-node can be equipped with "ngpios" property, which can't
have a value greater than 32, standard GPIO-related properties like
"gpio-controller" and "#gpio-cells", and, if GPIs are supposed to be
detected, IRQ-controller related properties.

Signed-off-by: Serge Semin <redacted>
---
 .../devicetree/bindings/net/snps,dwmac.yaml     | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/snps,dwmac.yaml b/Documentation/devicetree/bindings/net/snps,dwmac.yaml
index bdc437b14878..fcca23d3727e 100644
--- a/Documentation/devicetree/bindings/net/snps,dwmac.yaml
+++ b/Documentation/devicetree/bindings/net/snps,dwmac.yaml

@@ -110,6 +110,23 @@ properties:
   reset-names:
     const: stmmaceth
 
+  ngpios:
+    description:
+      Total number of GPIOs the MAC supports. The property shall include both
+      the GPI and GPO ports width.
+    minimum: 1
+    maximum: 32