[PATCH] dt-bindings: usb: samsung,exynos-dwc3: allow unit address in DTS

The Samsung Exynos SoC USB 3.0 DWC3 Controller is a simple wrapper of
actual DWC3 Controller device node.  It handles necessary Samsung
Exynos-specific resources (regulators, clocks), but does not have its
own MMIO address space.

However neither simple-bus bindings nor dtc W=1 accept device nodes in
soc@ node which do not have unit address.  Therefore allow using
the address space of child device (actual DWC3 Controller) as the
wrapper's address.

Signed-off-by: Krzysztof Kozlowski <redacted>

---

DTS fixes are here:
https://lore.kernel.org/linux-samsung-soc/20230125175751.675090-1-krzysztof.kozlowski@linaro.org/T/#t
---
 .../devicetree/bindings/usb/samsung,exynos-dwc3.yaml        | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/usb/samsung,exynos-dwc3.yaml b/Documentation/devicetree/bindings/usb/samsung,exynos-dwc3.yaml
index 6b9a3bcb3926..a94b1926dda0 100644
--- a/Documentation/devicetree/bindings/usb/samsung,exynos-dwc3.yaml
+++ b/Documentation/devicetree/bindings/usb/samsung,exynos-dwc3.yaml

@@ -29,6 +29,9 @@ properties:
 
   ranges: true
 
+  reg:
+    maxItems: 1
+
   '#size-cells':
     const: 1
 

@@ -108,8 +111,9 @@ examples:
     #include <dt-bindings/clock/exynos5420.h>
     #include <dt-bindings/interrupt-controller/arm-gic.h>
 
-    usb {
+    usb-wrapper@12000000 {
         compatible = "samsung,exynos5250-dwusb3";
+        reg = <0x12000000 0x10000>;
         #address-cells = <1>;
         #size-cells = <1>;
         ranges;

-- 
2.34.1

On Wed, Jan 25, 2023 at 06:59:43PM +0100, Krzysztof Kozlowski wrote:

The Samsung Exynos SoC USB 3.0 DWC3 Controller is a simple wrapper of
actual DWC3 Controller device node.  It handles necessary Samsung
Exynos-specific resources (regulators, clocks), but does not have its
own MMIO address space.

However neither simple-bus bindings nor dtc W=1 accept device nodes in
soc@ node which do not have unit address.  Therefore allow using
the address space of child device (actual DWC3 Controller) as the
wrapper's address.

The correct fix is 'ranges' should have a value. Though the whole 
wrapper thing when there are no registers I dislike...

On 25/01/2023 22:13, Rob Herring wrote:

On Wed, Jan 25, 2023 at 06:59:43PM +0100, Krzysztof Kozlowski wrote:

quoted

The Samsung Exynos SoC USB 3.0 DWC3 Controller is a simple wrapper of
actual DWC3 Controller device node.  It handles necessary Samsung
Exynos-specific resources (regulators, clocks), but does not have its
own MMIO address space.

However neither simple-bus bindings nor dtc W=1 accept device nodes in
soc@ node which do not have unit address.  Therefore allow using
the address space of child device (actual DWC3 Controller) as the
wrapper's address.

The correct fix is 'ranges' should have a value. Though the whole 
wrapper thing when there are no registers I dislike...

You mean something like this (diff against this patchset):
----------

diff --git a/arch/arm/boot/dts/exynos54xx.dtsi

b/arch/arm/boot/dts/exynos54xx.dtsi
index 08786fd9c6ea..75b6f9678672 100644

--- a/arch/arm/boot/dts/exynos54xx.dtsi
+++ b/arch/arm/boot/dts/exynos54xx.dtsi

@@ -142,16 +142,15 @@ hsi2c_7: i2c@12cd0000 {
                        status = "disabled";
                };

-               usbdrd3_0: usb-wrapper@12000000 {
+               usbdrd3_0: usb-wrapper {
                        compatible = "samsung,exynos5250-dwusb3";
-                       reg = <0x12000000 0x10000>;
                        #address-cells = <1>;
                        #size-cells = <1>;
-                       ranges;
+                       ranges = <0x0 0x12000000 0x10000>;

-                       usbdrd_dwc3_0: usb@12000000 {
+                       usbdrd_dwc3_0: usb@0 {
                                compatible = "snps,dwc3";
-                               reg = <0x12000000 0x10000>;
+                               reg = <0x0 0x10000>;

---------

Unfortunately dtc W=1 is still not happy:

exynos54xx.dtsi:145.26-159.5: Warning (unit_address_vs_reg):
/soc/usb-wrapper: node has a reg or ranges property, but no unit name

neither dtbs_check is:

exynos5410-smdk5410.dtb: soc: usb-wrapper: {'compatible':
['samsung,exynos5250-dwusb3'], '#address-cells': [[1]], '#size-cells':
[[1]], 'ranges': [[0, 301989888, 65536]], 'clocks': [[5, 366]],
'clock-names': ['usbdrd30'], 'pinctrl-names': ['default'], 'pinctrl-0':
[[21, 22]], 'vdd10-supply': [[23]], 'vdd33-supply': [[23]], 'usb@0':
{'compatible': ['snps,dwc3'], 'reg': [[0, 65536]], 'interrupts': [[0,
72, 4]], 'phys': [[24, 0], [24, 1]], 'phy-names': ['usb2-phy',
'usb3-phy'], 'snps,dis_u3_susphy_quirk': True}} should not be valid
under {'type': 'object'}
	From schema:
/home/krzk/.local/lib/python3.10/site-packages/dtschema/schemas/simple-bus.yaml


Best regards,
Krzysztof

On Thu, Jan 26, 2023 at 4:48 AM Krzysztof Kozlowski
[off-list ref] wrote:

Why did you drop the unit-address? Unit-address is valid with 'reg' or 'ranges'.

                        compatible = "samsung,exynos5250-dwusb3";
-                       reg = <0x12000000 0x10000>;
                        #address-cells = <1>;
                        #size-cells = <1>;
-                       ranges;
+                       ranges = <0x0 0x12000000 0x10000>;

-                       usbdrd_dwc3_0: usb@12000000 {
+                       usbdrd_dwc3_0: usb@0 {
                                compatible = "snps,dwc3";
-                               reg = <0x12000000 0x10000>;
+                               reg = <0x0 0x10000>;

---------

Unfortunately dtc W=1 is still not happy:

exynos54xx.dtsi:145.26-159.5: Warning (unit_address_vs_reg):
/soc/usb-wrapper: node has a reg or ranges property, but no unit name

neither dtbs_check is:

exynos5410-smdk5410.dtb: soc: usb-wrapper: {'compatible':
['samsung,exynos5250-dwusb3'], '#address-cells': [[1]], '#size-cells':
[[1]], 'ranges': [[0, 301989888, 65536]], 'clocks': [[5, 366]],
'clock-names': ['usbdrd30'], 'pinctrl-names': ['default'], 'pinctrl-0':
[[21, 22]], 'vdd10-supply': [[23]], 'vdd33-supply': [[23]], 'usb@0':
{'compatible': ['snps,dwc3'], 'reg': [[0, 65536]], 'interrupts': [[0,
72, 4]], 'phys': [[24, 0], [24, 1]], 'phy-names': ['usb2-phy',
'usb3-phy'], 'snps,dis_u3_susphy_quirk': True}} should not be valid
under {'type': 'object'}
        From schema:
/home/krzk/.local/lib/python3.10/site-packages/dtschema/schemas/simple-bus.yaml


Best regards,
Krzysztof

On 26/01/2023 14:41, Rob Herring wrote:

On Thu, Jan 26, 2023 at 4:48 AM Krzysztof Kozlowski
[off-list ref] wrote:

quoted

On 25/01/2023 22:13, Rob Herring wrote:

quoted

On Wed, Jan 25, 2023 at 06:59:43PM +0100, Krzysztof Kozlowski wrote:

quoted

The Samsung Exynos SoC USB 3.0 DWC3 Controller is a simple wrapper of
actual DWC3 Controller device node.  It handles necessary Samsung
Exynos-specific resources (regulators, clocks), but does not have its
own MMIO address space.

However neither simple-bus bindings nor dtc W=1 accept device nodes in
soc@ node which do not have unit address.  Therefore allow using
the address space of child device (actual DWC3 Controller) as the
wrapper's address.

The correct fix is 'ranges' should have a value. Though the whole
wrapper thing when there are no registers I dislike...

You mean something like this (diff against this patchset):
----------

diff --git a/arch/arm/boot/dts/exynos54xx.dtsi

b/arch/arm/boot/dts/exynos54xx.dtsi
index 08786fd9c6ea..75b6f9678672 100644

--- a/arch/arm/boot/dts/exynos54xx.dtsi
+++ b/arch/arm/boot/dts/exynos54xx.dtsi

@@ -142,16 +142,15 @@ hsi2c_7: i2c@12cd0000 {
                        status = "disabled";
                };

-               usbdrd3_0: usb-wrapper@12000000 {
+               usbdrd3_0: usb-wrapper {

Why did you drop the unit-address? Unit-address is valid with 'reg' or 'ranges'.

I misunderstood your comment then. To which problem did you refer with
"The correct fix is ranges ...."? To my understanding this only changes
the unit address, so I won't have to change the node name
usb->usb-wrapper. Except this, my patches having empty ranges are
equivalent.

quoted

                        compatible = "samsung,exynos5250-dwusb3";
-                       reg = <0x12000000 0x10000>;
                        #address-cells = <1>;
                        #size-cells = <1>;
-                       ranges;
+                       ranges = <0x0 0x12000000 0x10000>;

Best regards,
Krzysztof