In the case of Renesas R-Car hardware we know that there are generations of
SoCs, e.g. Gen 2 and Gen 3. But beyond that its not clear what the
relationship between IP blocks might be. For example, I believe that
r8a7790 is older than r8a7791 but that doesn't imply that the latter is a
descendant of the former or vice versa.
We can, however, by examining the documentation and behaviour of the
hardware at run-time observe that the current driver implementation appears
to be compatible with the IP blocks on SoCs within a given generation.
For the above reasons and convenience when enabling new SoCs a
per-generation fallback compatibility string scheme being adopted for
drivers for Renesas SoCs.
Signed-off-by: Simon Horman <horms+renesas@xxxxxxxxxxxx>
---
Documentation/devicetree/bindings/phy/rcar-gen2-phy.txt | 8 +++++++-
drivers/phy/phy-rcar-gen2.c | 1 +
2 files changed, 8 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/phy/rcar-gen2-phy.txt b/Documentation/devicetree/bindings/phy/rcar-gen2-phy.txt
index d564ba4f1cf6..f1102ee464fb 100644
--- a/Documentation/devicetree/bindings/phy/rcar-gen2-phy.txt
+++ b/Documentation/devicetree/bindings/phy/rcar-gen2-phy.txt
@@ -7,6 +7,12 @@ Required properties:
- compatible: "renesas,usb-phy-r8a7790" if the device is a part of R8A7790 SoC.
"renesas,usb-phy-r8a7791" if the device is a part of R8A7791 SoC.
"renesas,usb-phy-r8a7794" if the device is a part of R8A7794 SoC.
+ "renesas,usb-phy-gen2" for a generic R-Car Gen2 compatible device.
+
+ When compatible with the generic version, nodes must list the
+ SoC-specific version corresponding to the platform first
+ followed by the generic version.
+
- reg: offset and length of the register block.
- #address-cells: number of address cells for the USB channel subnodes, must
be <1>.
@@ -34,7 +40,7 @@ the USB channel; see the selector meanings below:
Example (Lager board):
usb-phy@e6590100 {
- compatible = "renesas,usb-phy-r8a7790";
+ compatible = "renesas,usb-phy-r8a7790","renesas,usb-phy-gen2";
reg = <0 0xe6590100 0 0x100>;
#address-cells = <1>;
#size-cells = <0>;
diff --git a/drivers/phy/phy-rcar-gen2.c b/drivers/phy/phy-rcar-gen2.c
index c7a05996d5c1..e10d326d51e7 100644
--- a/drivers/phy/phy-rcar-gen2.c
+++ b/drivers/phy/phy-rcar-gen2.c
@@ -195,6 +195,7 @@ static const struct of_device_id rcar_gen2_phy_match_table[] = {
{ .compatible = "renesas,usb-phy-r8a7790" },
{ .compatible = "renesas,usb-phy-r8a7791" },
{ .compatible = "renesas,usb-phy-r8a7794" },
+ { .compatible = "renesas,usb-phy-gen2" },
{ }
};
MODULE_DEVICE_TABLE(of, rcar_gen2_phy_match_table);
--
2.1.4
