[PATCH v5 0/2] Add SpacemiT K1 USB3.0 host controller support

[PATCH v5 0/2] Add SpacemiT K1 USB3.0 host controller support

[Ze Huang]

The USB 3.0 controller found in the SpacemiT K1 SoC[1] supports both USB3.0
Host and USB2.0 Dual-Role Device (DRD). 

This controller is compatible with DesignWare Core USB 3 (DWC3) driver.
However, constraints in the `snps,dwc3` bindings limit the ability to describe
hardware-specific features in a clean and maintainable way. While
`dwc3-of-simple` still serves as a glue layer for many platforms, it requires a
split device tree node structure, which is less desirable in newer platforms.

To promote a transition toward a flattened `dwc` node structure, this series
introduces `dwc3-generic-plat`, building upon prior efforts that exposed the
DWC3 core driver [2].

The device tree support for SpacemiT K1 will be submitted separately when the
associated PHY driver is ready.

This series is based on 6.16-rc1 and has been tested on BananaPi development
boards.

Link: https://developer.spacemit.com/documentation?token=AjHDwrW78igAAEkiHracBI9HnTb [1]
Link: https://lore.kernel.org/all/20250414-dwc3-refactor-v7-3-f015b358722d@oss.qualcomm.com [2]

Signed-off-by: Ze Huang <huang.ze@linux.dev>
---
Changes in v5:
- drop DTS patch (will submit when PHY driver is ready)
- drop interconnects and update resets property in dt-bindings
- remove unnecessary __maybe_unused attribute and PM guards
- switch to devres APIs for reset and clock management
- Link to v4: https://lore.kernel.org/all/20250526-b4-k1-dwc3-v3-v4-0-63e4e525e5cb@whut.edu.cn/

Changes in v4:
- dt-bindings spacemit,k1-dwc:
  - reorder properties
  - add properties of phys & phy-names
  - add usb hub nodes in example dt
- add support for spacemit,k1-mbus
- dwc3 generic plat driver:
  - rename dwc3-common.c to dwc3-generic-plat.c
  - use SYSTEM_SLEEP_PM_OPS macros and drop PM guards
- dts:
  - reorder dts properties of usb dwc3 node
  - move "dr_mode" of dwc3 from dtsi to dts
- Link to v3: https://lore.kernel.org/r/20250518-b4-k1-dwc3-v3-v3-0-7609c8baa2a6@whut.edu.cn

Changes in v3:
- introduce dwc3-common for generic dwc3 hardware
- fix warnings in usb host dt-bindings
- fix errors in dts
- Link to v2: https://lore.kernel.org/r/20250428-b4-k1-dwc3-v2-v1-0-7cb061abd619@whut.edu.cn

Changes in v2:
- dt-bindings:
  - add missing 'maxItems'
  - remove 'status' property in exmaple
  - fold dwc3 node into parent
- drop dwc3 glue driver and use snps,dwc3 driver directly
- rename dts nodes and reorder properties to fit coding style
- Link to v1: https://lore.kernel.org/all/20250407-b4-k1-usb3-v3-2-v1-0-bf0bcc41c9ba@whut.edu.cn

---
Ze Huang (2):
      dt-bindings: usb: dwc3: add support for SpacemiT K1
      usb: dwc3: add generic driver to support flattened

 .../devicetree/bindings/usb/spacemit,k1-dwc3.yaml  | 107 ++++++++++++
 drivers/usb/dwc3/Kconfig                           |  11 ++
 drivers/usb/dwc3/Makefile                          |   1 +
 drivers/usb/dwc3/dwc3-generic-plat.c               | 182 +++++++++++++++++++++
 4 files changed, 301 insertions(+)
---
base-commit: d9946fe286439c2aeaa7953b8c316efe5b83d515
change-id: 20250705-dwc3_generic-8d02859722c3

Best regards,
-- 
Ze Huang <huang.ze@linux.dev>

[PATCH v5 1/2] dt-bindings: usb: dwc3: add support for SpacemiT K1

[Ze Huang]

Add support for the USB 3.0 Dual-Role Device (DRD) controller embedded
in the SpacemiT K1 SoC. The controller is based on the Synopsys
DesignWare Core USB 3 (DWC3) IP, supporting USB3.0 host mode and USB 2.0
DRD mode.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Ze Huang <huang.ze@linux.dev>
---
 .../devicetree/bindings/usb/spacemit,k1-dwc3.yaml  | 107 +++++++++++++++++++++
 1 file changed, 107 insertions(+)

diff --git a/Documentation/devicetree/bindings/usb/spacemit,k1-dwc3.yaml b/Documentation/devicetree/bindings/usb/spacemit,k1-dwc3.yaml
new file mode 100644
index 0000000000000000000000000000000000000000..c967ad6aae50199127a4f8a17d53fc34e8d9480b
--- /dev/null
+++ b/Documentation/devicetree/bindings/usb/spacemit,k1-dwc3.yaml
@@ -0,0 +1,107 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/usb/spacemit,k1-dwc3.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SpacemiT K1 SuperSpeed DWC3 USB SoC Controller
+
+maintainers:
+  - Ze Huang <huang.ze@linux.dev>
+
+description: |
+  The SpacemiT K1 embeds a DWC3 USB IP Core which supports Host functions
+  for USB 3.0 and DRD for USB 2.0.
+
+  Key features:
+  - USB3.0 SuperSpeed and USB2.0 High/Full/Low-Speed support
+  - Supports low-power modes (USB2.0 suspend, USB3.0 U1/U2/U3)
+  - Internal DMA controller and flexible endpoint FIFO sizing
+
+  Communication Interface:
+  - Use of PIPE3 (125MHz) interface for USB3.0 PHY
+  - Use of UTMI+ (30/60MHz) interface for USB2.0 PHY
+
+allOf:
+  - $ref: snps,dwc3-common.yaml#
+
+properties:
+  compatible:
+    const: spacemit,k1-dwc3
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  clock-names:
+    const: usbdrd30
+
+  interrupts:
+    maxItems: 1
+
+  phys:
+    items:
+      - description: phandle to USB2/HS PHY
+      - description: phandle to USB3/SS PHY
+
+  phy-names:
+    items:
+      - const: usb2-phy
+      - const: usb3-phy
+
+  resets:
+    items:
+      - description: USB3.0 AHB reset line
+      - description: USB3.0 VCC reset line
+      - description: USB3.0 PHY reset line
+
+  vbus-supply:
+    description: A phandle to the regulator supplying the VBUS voltage.
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+  - interrupts
+  - phys
+  - phy-names
+  - resets
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    usb@c0a00000 {
+        compatible = "spacemit,k1-dwc3";
+        reg = <0xc0a00000 0x10000>;
+        clocks = <&syscon_apmu 16>;
+        clock-names = "usbdrd30";
+        interrupts = <125>;
+        phys = <&usb2phy>, <&usb3phy>;
+        phy-names = "usb2-phy", "usb3-phy";
+        resets = <&syscon_apmu 8>,
+                 <&syscon_apmu 9>,
+                 <&syscon_apmu 10>;
+        vbus-supply = <&usb3_vbus>;
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        hub_2_0: hub@1 {
+            compatible = "usb2109,2817";
+            reg = <1>;
+            vdd-supply = <&usb3_vhub>;
+            peer-hub = <&hub_3_0>;
+            reset-gpios = <&gpio 3 28 1>;
+        };
+
+        hub_3_0: hub@2 {
+            compatible = "usb2109,817";
+            reg = <2>;
+            vdd-supply = <&usb3_vhub>;
+            peer-hub = <&hub_2_0>;
+            reset-gpios = <&gpio 3 28 1>;
+        };
+    };

-- 
2.50.0

Re: [PATCH v5 1/2] dt-bindings: usb: dwc3: add support for SpacemiT K1

[Ze Huang]

On Sat, Jul 05, 2025 at 09:01:25PM +0800, Ze Huang wrote:
> Add support for the USB 3.0 Dual-Role Device (DRD) controller embedded
> in the SpacemiT K1 SoC. The controller is based on the Synopsys
> DesignWare Core USB 3 (DWC3) IP, supporting USB3.0 host mode and USB 2.0
> DRD mode.
> 
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> Signed-off-by: Ze Huang <huang.ze@linux.dev>
> ---

Hi Krzysztof,

I kept your Reviewed-by tag, as this version only includes minor updates:
- Dropped the `interconnects` property
- Updated the `resets` property to match the latest convention from Alex's patch

Let me know if you have any concerns.

>  .../devicetree/bindings/usb/spacemit,k1-dwc3.yaml  | 107 +++++++++++++++++++++
>  1 file changed, 107 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/usb/spacemit,k1-dwc3.yaml b/Documentation/devicetree/bindings/usb/spacemit,k1-dwc3.yaml
> new file mode 100644
> index 0000000000000000000000000000000000000000..c967ad6aae50199127a4f8a17d53fc34e8d9480b
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/usb/spacemit,k1-dwc3.yaml
> @@ -0,0 +1,107 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/usb/spacemit,k1-dwc3.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: SpacemiT K1 SuperSpeed DWC3 USB SoC Controller
> +
> +maintainers:
> +  - Ze Huang <huang.ze@linux.dev>
> +
> +description: |
> +  The SpacemiT K1 embeds a DWC3 USB IP Core which supports Host functions
> +  for USB 3.0 and DRD for USB 2.0.
> +
> +  Key features:
> +  - USB3.0 SuperSpeed and USB2.0 High/Full/Low-Speed support
> +  - Supports low-power modes (USB2.0 suspend, USB3.0 U1/U2/U3)
> +  - Internal DMA controller and flexible endpoint FIFO sizing
> +
> +  Communication Interface:
> +  - Use of PIPE3 (125MHz) interface for USB3.0 PHY
> +  - Use of UTMI+ (30/60MHz) interface for USB2.0 PHY
> +
> +allOf:
> +  - $ref: snps,dwc3-common.yaml#
> +
> +properties:
> +  compatible:
> +    const: spacemit,k1-dwc3
> +
> +  reg:
> +    maxItems: 1
> +
> +  clocks:
> +    maxItems: 1
> +
> +  clock-names:
> +    const: usbdrd30
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  phys:
> +    items:
> +      - description: phandle to USB2/HS PHY
> +      - description: phandle to USB3/SS PHY
> +
> +  phy-names:
> +    items:
> +      - const: usb2-phy
> +      - const: usb3-phy
> +
> +  resets:
> +    items:
> +      - description: USB3.0 AHB reset line
> +      - description: USB3.0 VCC reset line
> +      - description: USB3.0 PHY reset line
> +
> +  vbus-supply:
> +    description: A phandle to the regulator supplying the VBUS voltage.
> +
> +required:
> +  - compatible
> +  - reg
> +  - clocks
> +  - clock-names
> +  - interrupts
> +  - phys
> +  - phy-names
> +  - resets
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    usb@c0a00000 {
> +        compatible = "spacemit,k1-dwc3";
> +        reg = <0xc0a00000 0x10000>;
> +        clocks = <&syscon_apmu 16>;
> +        clock-names = "usbdrd30";
> +        interrupts = <125>;
> +        phys = <&usb2phy>, <&usb3phy>;
> +        phy-names = "usb2-phy", "usb3-phy";
> +        resets = <&syscon_apmu 8>,
> +                 <&syscon_apmu 9>,
> +                 <&syscon_apmu 10>;
> +        vbus-supply = <&usb3_vbus>;
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        hub_2_0: hub@1 {
> +            compatible = "usb2109,2817";
> +            reg = <1>;
> +            vdd-supply = <&usb3_vhub>;
> +            peer-hub = <&hub_3_0>;
> +            reset-gpios = <&gpio 3 28 1>;
> +        };
> +
> +        hub_3_0: hub@2 {
> +            compatible = "usb2109,817";
> +            reg = <2>;
> +            vdd-supply = <&usb3_vhub>;
> +            peer-hub = <&hub_2_0>;
> +            reset-gpios = <&gpio 3 28 1>;
> +        };
> +    };
> 
> -- 
> 2.50.0
> 

Re: [PATCH v5 1/2] dt-bindings: usb: dwc3: add support for SpacemiT K1

[Krzysztof Kozlowski]

On 05/07/2025 15:10, Ze Huang wrote:
> On Sat, Jul 05, 2025 at 09:01:25PM +0800, Ze Huang wrote:
>> Add support for the USB 3.0 Dual-Role Device (DRD) controller embedded
>> in the SpacemiT K1 SoC. The controller is based on the Synopsys
>> DesignWare Core USB 3 (DWC3) IP, supporting USB3.0 host mode and USB 2.0
>> DRD mode.
>>
>> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>> Signed-off-by: Ze Huang <huang.ze@linux.dev>
>> ---
> 
> Hi Krzysztof,
> 
> I kept your Reviewed-by tag, as this version only includes minor updates:
> - Dropped the `interconnects` property
> - Updated the `resets` property to match the latest convention from Alex's patch
> 
> Let me know if you have any concerns.

It's fine, thanks.

Best regards,
Krzysztof

[PATCH v5 2/2] usb: dwc3: add generic driver to support flattened

[Ze Huang]

To support flattened dwc3 dt model and drop the glue layer, introduce the
`dwc3-generic` driver. This enables direct binding of the DWC3 core driver
and offers an alternative to the existing glue driver `dwc3-of-simple`.

Signed-off-by: Ze Huang <huang.ze@linux.dev>
---
 drivers/usb/dwc3/Kconfig             |  11 +++
 drivers/usb/dwc3/Makefile            |   1 +
 drivers/usb/dwc3/dwc3-generic-plat.c | 182 +++++++++++++++++++++++++++++++++++
 3 files changed, 194 insertions(+)

diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
index 310d182e10b50b253d7e5a51674806e6ec442a2a..4925d15084f816d3ff92059b476ebcc799b56b51 100644
--- a/drivers/usb/dwc3/Kconfig
+++ b/drivers/usb/dwc3/Kconfig
@@ -189,4 +189,15 @@ config USB_DWC3_RTK
 	  or dual-role mode.
 	  Say 'Y' or 'M' if you have such device.
 
+config USB_DWC3_GENERIC_PLAT
+	tristate "DWC3 Generic Platform Driver"
+	depends on OF && COMMON_CLK
+	default USB_DWC3
+	help
+	  Support USB3 functionality in simple SoC integrations.
+	  Currently supports SpacemiT DWC USB3. Platforms using
+	  dwc3-of-simple can easily switch to dwc3-generic by flattening
+	  the dwc3 child node in the device tree.
+	  Say 'Y' or 'M' here if your platform integrates DWC3 in a similar way.
+
 endif
diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
index 830e6c9e5fe073c1f662ce34b6a4a2da34c407a2..96469e48ff9d189cc8d0b65e65424eae2158bcfe 100644
--- a/drivers/usb/dwc3/Makefile
+++ b/drivers/usb/dwc3/Makefile
@@ -57,3 +57,4 @@ obj-$(CONFIG_USB_DWC3_IMX8MP)		+= dwc3-imx8mp.o
 obj-$(CONFIG_USB_DWC3_XILINX)		+= dwc3-xilinx.o
 obj-$(CONFIG_USB_DWC3_OCTEON)		+= dwc3-octeon.o
 obj-$(CONFIG_USB_DWC3_RTK)		+= dwc3-rtk.o
+obj-$(CONFIG_USB_DWC3_GENERIC_PLAT)	+= dwc3-generic-plat.o
diff --git a/drivers/usb/dwc3/dwc3-generic-plat.c b/drivers/usb/dwc3/dwc3-generic-plat.c
new file mode 100644
index 0000000000000000000000000000000000000000..f251dda60903364d6b326a0904ec9b113e61f5c0
--- /dev/null
+++ b/drivers/usb/dwc3/dwc3-generic-plat.c
@@ -0,0 +1,182 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * dwc3-generic-plat.c - DesignWare USB3 generic platform driver
+ *
+ * Copyright (C) 2025 Ze Huang <huang.ze@linux.dev>
+ *
+ * Inspired by dwc3-qcom.c and dwc3-of-simple.c
+ */
+
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+#include "glue.h"
+
+struct dwc3_generic {
+	struct device		*dev;
+	struct dwc3		dwc;
+	struct clk_bulk_data	*clks;
+	int			num_clocks;
+	struct reset_control	*resets;
+};
+
+static void dwc3_generic_reset_control_assert(void *data)
+{
+	reset_control_assert(data);
+}
+
+static void dwc3_generic_clk_bulk_disable_unprepare(void *data)
+{
+	struct dwc3_generic *dwc3 = data;
+
+	clk_bulk_disable_unprepare(dwc3->num_clocks, dwc3->clks);
+}
+
+static int dwc3_generic_probe(struct platform_device *pdev)
+{
+	struct dwc3_probe_data probe_data = {};
+	struct device *dev = &pdev->dev;
+	struct dwc3_generic *dwc3;
+	struct resource *res;
+	int ret;
+
+	dwc3 = devm_kzalloc(dev, sizeof(*dwc3), GFP_KERNEL);
+	if (!dwc3)
+		return -ENOMEM;
+
+	dwc3->dev = dev;
+
+	platform_set_drvdata(pdev, dwc3);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "missing memory resource\n");
+		return -ENODEV;
+	}
+
+	dwc3->resets = devm_reset_control_array_get_optional_exclusive(dev);
+	if (IS_ERR(dwc3->resets))
+		return dev_err_probe(dev, PTR_ERR(dwc3->resets), "failed to get resets\n");
+
+	ret = reset_control_assert(dwc3->resets);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to assert resets\n");
+
+	ret = devm_add_action_or_reset(dev, dwc3_generic_reset_control_assert, dwc3->resets);
+	if (ret)
+		return ret;
+
+	usleep_range(10, 1000);
+
+	ret = reset_control_deassert(dwc3->resets);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to deassert resets\n");
+
+	ret = devm_clk_bulk_get_all(dwc3->dev, &dwc3->clks);
+	if (ret < 0)
+		return dev_err_probe(dev, ret, "failed to get clocks\n");
+
+	dwc3->num_clocks = ret;
+
+	ret = clk_bulk_prepare_enable(dwc3->num_clocks, dwc3->clks);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to enable clocks\n");
+
+	ret = devm_add_action_or_reset(dev, dwc3_generic_clk_bulk_disable_unprepare, dwc3);
+	if (ret)
+		return ret;
+
+	dwc3->dwc.dev = dev;
+	probe_data.dwc = &dwc3->dwc;
+	probe_data.res = res;
+	probe_data.ignore_clocks_and_resets = true;
+	ret = dwc3_core_probe(&probe_data);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to register DWC3 Core\n");
+
+	return 0;
+}
+
+static void dwc3_generic_remove(struct platform_device *pdev)
+{
+	struct dwc3_generic *dwc3 = platform_get_drvdata(pdev);
+
+	dwc3_core_remove(&dwc3->dwc);
+}
+
+static int dwc3_generic_suspend(struct device *dev)
+{
+	struct dwc3_generic *dwc3 = dev_get_drvdata(dev);
+	int ret;
+
+	ret = dwc3_pm_suspend(&dwc3->dwc);
+	if (ret)
+		return ret;
+
+	clk_bulk_disable_unprepare(dwc3->num_clocks, dwc3->clks);
+
+	return 0;
+}
+
+static int dwc3_generic_resume(struct device *dev)
+{
+	struct dwc3_generic *dwc3 = dev_get_drvdata(dev);
+	int ret;
+
+	ret = clk_bulk_prepare_enable(dwc3->num_clocks, dwc3->clks);
+	if (ret)
+		return ret;
+
+	ret = dwc3_pm_resume(&dwc3->dwc);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int dwc3_generic_runtime_suspend(struct device *dev)
+{
+	struct dwc3_generic *dwc3 = dev_get_drvdata(dev);
+
+	return dwc3_runtime_suspend(&dwc3->dwc);
+}
+
+static int dwc3_generic_runtime_resume(struct device *dev)
+{
+	struct dwc3_generic *dwc3 = dev_get_drvdata(dev);
+
+	return dwc3_runtime_resume(&dwc3->dwc);
+}
+
+static int dwc3_generic_runtime_idle(struct device *dev)
+{
+	struct dwc3_generic *dwc3 = dev_get_drvdata(dev);
+
+	return dwc3_runtime_idle(&dwc3->dwc);
+}
+
+static const struct dev_pm_ops dwc3_generic_dev_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(dwc3_generic_suspend, dwc3_generic_resume)
+	SET_RUNTIME_PM_OPS(dwc3_generic_runtime_suspend, dwc3_generic_runtime_resume,
+			   dwc3_generic_runtime_idle)
+};
+
+static const struct of_device_id dwc3_generic_of_match[] = {
+	{ .compatible = "spacemit,k1-dwc3", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, dwc3_generic_of_match);
+
+static struct platform_driver dwc3_generic_driver = {
+	.probe		= dwc3_generic_probe,
+	.remove		= dwc3_generic_remove,
+	.driver		= {
+		.name	= "dwc3-generic-plat",
+		.of_match_table = dwc3_generic_of_match,
+		.pm	= &dwc3_generic_dev_pm_ops,
+	},
+};
+module_platform_driver(dwc3_generic_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("DesignWare USB3 generic platform driver");

-- 
2.50.0

Re: [PATCH v5 2/2] usb: dwc3: add generic driver to support flattened

[kernel test robot]

Hi Ze,

kernel test robot noticed the following build warnings:

[auto build test WARNING on d9946fe286439c2aeaa7953b8c316efe5b83d515]

url:    https://github.com/intel-lab-lkp/linux/commits/Ze-Huang/dt-bindings-usb-dwc3-add-support-for-SpacemiT-K1/20250705-210419
base:   d9946fe286439c2aeaa7953b8c316efe5b83d515
patch link:    https://lore.kernel.org/r/20250705-dwc3_generic-v5-2-9dbc53ea53d2%40linux.dev
patch subject: [PATCH v5 2/2] usb: dwc3: add generic driver to support flattened
config: arc-randconfig-001-20250706 (https://download.01.org/0day-ci/archive/20250706/202507060206.iiBP6CQi-lkp@intel.com/config)
compiler: arc-linux-gcc (GCC) 8.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250706/202507060206.iiBP6CQi-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202507060206.iiBP6CQi-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/usb/dwc3/dwc3-generic-plat.c:151:12: warning: 'dwc3_generic_runtime_idle' defined but not used [-Wunused-function]
    static int dwc3_generic_runtime_idle(struct device *dev)
               ^~~~~~~~~~~~~~~~~~~~~~~~~
>> drivers/usb/dwc3/dwc3-generic-plat.c:144:12: warning: 'dwc3_generic_runtime_resume' defined but not used [-Wunused-function]
    static int dwc3_generic_runtime_resume(struct device *dev)
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~
>> drivers/usb/dwc3/dwc3-generic-plat.c:137:12: warning: 'dwc3_generic_runtime_suspend' defined but not used [-Wunused-function]
    static int dwc3_generic_runtime_suspend(struct device *dev)
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> drivers/usb/dwc3/dwc3-generic-plat.c:121:12: warning: 'dwc3_generic_resume' defined but not used [-Wunused-function]
    static int dwc3_generic_resume(struct device *dev)
               ^~~~~~~~~~~~~~~~~~~
>> drivers/usb/dwc3/dwc3-generic-plat.c:107:12: warning: 'dwc3_generic_suspend' defined but not used [-Wunused-function]
    static int dwc3_generic_suspend(struct device *dev)
               ^~~~~~~~~~~~~~~~~~~~


vim +/dwc3_generic_runtime_idle +151 drivers/usb/dwc3/dwc3-generic-plat.c

   106	
 > 107	static int dwc3_generic_suspend(struct device *dev)
   108	{
   109		struct dwc3_generic *dwc3 = dev_get_drvdata(dev);
   110		int ret;
   111	
   112		ret = dwc3_pm_suspend(&dwc3->dwc);
   113		if (ret)
   114			return ret;
   115	
   116		clk_bulk_disable_unprepare(dwc3->num_clocks, dwc3->clks);
   117	
   118		return 0;
   119	}
   120	
 > 121	static int dwc3_generic_resume(struct device *dev)
   122	{
   123		struct dwc3_generic *dwc3 = dev_get_drvdata(dev);
   124		int ret;
   125	
   126		ret = clk_bulk_prepare_enable(dwc3->num_clocks, dwc3->clks);
   127		if (ret)
   128			return ret;
   129	
   130		ret = dwc3_pm_resume(&dwc3->dwc);
   131		if (ret)
   132			return ret;
   133	
   134		return 0;
   135	}
   136	
 > 137	static int dwc3_generic_runtime_suspend(struct device *dev)
   138	{
   139		struct dwc3_generic *dwc3 = dev_get_drvdata(dev);
   140	
   141		return dwc3_runtime_suspend(&dwc3->dwc);
   142	}
   143	
 > 144	static int dwc3_generic_runtime_resume(struct device *dev)
   145	{
   146		struct dwc3_generic *dwc3 = dev_get_drvdata(dev);
   147	
   148		return dwc3_runtime_resume(&dwc3->dwc);
   149	}
   150	
 > 151	static int dwc3_generic_runtime_idle(struct device *dev)
   152	{
   153		struct dwc3_generic *dwc3 = dev_get_drvdata(dev);
   154	
   155		return dwc3_runtime_idle(&dwc3->dwc);
   156	}
   157	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH v5 2/2] usb: dwc3: add generic driver to support flattened

[Thinh Nguyen]

On Sat, Jul 05, 2025, Ze Huang wrote:
> To support flattened dwc3 dt model and drop the glue layer, introduce the
> `dwc3-generic` driver. This enables direct binding of the DWC3 core driver
> and offers an alternative to the existing glue driver `dwc3-of-simple`.
> 
> Signed-off-by: Ze Huang <huang.ze@linux.dev>
> ---
>  drivers/usb/dwc3/Kconfig             |  11 +++
>  drivers/usb/dwc3/Makefile            |   1 +
>  drivers/usb/dwc3/dwc3-generic-plat.c | 182 +++++++++++++++++++++++++++++++++++
>  3 files changed, 194 insertions(+)
> 
> diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
> index 310d182e10b50b253d7e5a51674806e6ec442a2a..4925d15084f816d3ff92059b476ebcc799b56b51 100644
> --- a/drivers/usb/dwc3/Kconfig
> +++ b/drivers/usb/dwc3/Kconfig
> @@ -189,4 +189,15 @@ config USB_DWC3_RTK
>  	  or dual-role mode.
>  	  Say 'Y' or 'M' if you have such device.
>  
> +config USB_DWC3_GENERIC_PLAT
> +	tristate "DWC3 Generic Platform Driver"
> +	depends on OF && COMMON_CLK
> +	default USB_DWC3
> +	help
> +	  Support USB3 functionality in simple SoC integrations.
> +	  Currently supports SpacemiT DWC USB3. Platforms using
> +	  dwc3-of-simple can easily switch to dwc3-generic by flattening
> +	  the dwc3 child node in the device tree.
> +	  Say 'Y' or 'M' here if your platform integrates DWC3 in a similar way.
> +
>  endif
> diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
> index 830e6c9e5fe073c1f662ce34b6a4a2da34c407a2..96469e48ff9d189cc8d0b65e65424eae2158bcfe 100644
> --- a/drivers/usb/dwc3/Makefile
> +++ b/drivers/usb/dwc3/Makefile
> @@ -57,3 +57,4 @@ obj-$(CONFIG_USB_DWC3_IMX8MP)		+= dwc3-imx8mp.o
>  obj-$(CONFIG_USB_DWC3_XILINX)		+= dwc3-xilinx.o
>  obj-$(CONFIG_USB_DWC3_OCTEON)		+= dwc3-octeon.o
>  obj-$(CONFIG_USB_DWC3_RTK)		+= dwc3-rtk.o
> +obj-$(CONFIG_USB_DWC3_GENERIC_PLAT)	+= dwc3-generic-plat.o
> diff --git a/drivers/usb/dwc3/dwc3-generic-plat.c b/drivers/usb/dwc3/dwc3-generic-plat.c
> new file mode 100644
> index 0000000000000000000000000000000000000000..f251dda60903364d6b326a0904ec9b113e61f5c0
> --- /dev/null
> +++ b/drivers/usb/dwc3/dwc3-generic-plat.c
> @@ -0,0 +1,182 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * dwc3-generic-plat.c - DesignWare USB3 generic platform driver
> + *
> + * Copyright (C) 2025 Ze Huang <huang.ze@linux.dev>
> + *
> + * Inspired by dwc3-qcom.c and dwc3-of-simple.c
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/platform_device.h>
> +#include <linux/reset.h>
> +#include "glue.h"
> +
> +struct dwc3_generic {
> +	struct device		*dev;
> +	struct dwc3		dwc;
> +	struct clk_bulk_data	*clks;
> +	int			num_clocks;
> +	struct reset_control	*resets;
> +};
> +
> +static void dwc3_generic_reset_control_assert(void *data)
> +{
> +	reset_control_assert(data);
> +}
> +
> +static void dwc3_generic_clk_bulk_disable_unprepare(void *data)
> +{
> +	struct dwc3_generic *dwc3 = data;
> +
> +	clk_bulk_disable_unprepare(dwc3->num_clocks, dwc3->clks);
> +}
> +
> +static int dwc3_generic_probe(struct platform_device *pdev)
> +{
> +	struct dwc3_probe_data probe_data = {};
> +	struct device *dev = &pdev->dev;
> +	struct dwc3_generic *dwc3;
> +	struct resource *res;
> +	int ret;
> +
> +	dwc3 = devm_kzalloc(dev, sizeof(*dwc3), GFP_KERNEL);
> +	if (!dwc3)
> +		return -ENOMEM;
> +
> +	dwc3->dev = dev;
> +
> +	platform_set_drvdata(pdev, dwc3);
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		dev_err(&pdev->dev, "missing memory resource\n");
> +		return -ENODEV;
> +	}
> +
> +	dwc3->resets = devm_reset_control_array_get_optional_exclusive(dev);
> +	if (IS_ERR(dwc3->resets))
> +		return dev_err_probe(dev, PTR_ERR(dwc3->resets), "failed to get resets\n");
> +
> +	ret = reset_control_assert(dwc3->resets);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "failed to assert resets\n");
> +
> +	ret = devm_add_action_or_reset(dev, dwc3_generic_reset_control_assert, dwc3->resets);
> +	if (ret)
> +		return ret;
> +
> +	usleep_range(10, 1000);
> +
> +	ret = reset_control_deassert(dwc3->resets);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "failed to deassert resets\n");
> +
> +	ret = devm_clk_bulk_get_all(dwc3->dev, &dwc3->clks);
> +	if (ret < 0)
> +		return dev_err_probe(dev, ret, "failed to get clocks\n");
> +
> +	dwc3->num_clocks = ret;
> +
> +	ret = clk_bulk_prepare_enable(dwc3->num_clocks, dwc3->clks);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "failed to enable clocks\n");
> +
> +	ret = devm_add_action_or_reset(dev, dwc3_generic_clk_bulk_disable_unprepare, dwc3);
> +	if (ret)
> +		return ret;
> +
> +	dwc3->dwc.dev = dev;
> +	probe_data.dwc = &dwc3->dwc;
> +	probe_data.res = res;
> +	probe_data.ignore_clocks_and_resets = true;
> +	ret = dwc3_core_probe(&probe_data);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "failed to register DWC3 Core\n");
> +
> +	return 0;
> +}
> +
> +static void dwc3_generic_remove(struct platform_device *pdev)
> +{
> +	struct dwc3_generic *dwc3 = platform_get_drvdata(pdev);
> +
> +	dwc3_core_remove(&dwc3->dwc);
> +}
> +
> +static int dwc3_generic_suspend(struct device *dev)
> +{
> +	struct dwc3_generic *dwc3 = dev_get_drvdata(dev);
> +	int ret;
> +
> +	ret = dwc3_pm_suspend(&dwc3->dwc);
> +	if (ret)
> +		return ret;
> +
> +	clk_bulk_disable_unprepare(dwc3->num_clocks, dwc3->clks);
> +
> +	return 0;
> +}
> +
> +static int dwc3_generic_resume(struct device *dev)
> +{
> +	struct dwc3_generic *dwc3 = dev_get_drvdata(dev);
> +	int ret;
> +
> +	ret = clk_bulk_prepare_enable(dwc3->num_clocks, dwc3->clks);
> +	if (ret)
> +		return ret;
> +
> +	ret = dwc3_pm_resume(&dwc3->dwc);
> +	if (ret)
> +		return ret;
> +
> +	return 0;
> +}
> +
> +static int dwc3_generic_runtime_suspend(struct device *dev)
> +{
> +	struct dwc3_generic *dwc3 = dev_get_drvdata(dev);
> +
> +	return dwc3_runtime_suspend(&dwc3->dwc);
> +}
> +
> +static int dwc3_generic_runtime_resume(struct device *dev)
> +{
> +	struct dwc3_generic *dwc3 = dev_get_drvdata(dev);
> +
> +	return dwc3_runtime_resume(&dwc3->dwc);
> +}
> +
> +static int dwc3_generic_runtime_idle(struct device *dev)
> +{
> +	struct dwc3_generic *dwc3 = dev_get_drvdata(dev);
> +
> +	return dwc3_runtime_idle(&dwc3->dwc);
> +}
> +
> +static const struct dev_pm_ops dwc3_generic_dev_pm_ops = {
> +	SET_SYSTEM_SLEEP_PM_OPS(dwc3_generic_suspend, dwc3_generic_resume)
> +	SET_RUNTIME_PM_OPS(dwc3_generic_runtime_suspend, dwc3_generic_runtime_resume,
> +			   dwc3_generic_runtime_idle)
> +};
> +
> +static const struct of_device_id dwc3_generic_of_match[] = {
> +	{ .compatible = "spacemit,k1-dwc3", },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, dwc3_generic_of_match);
> +
> +static struct platform_driver dwc3_generic_driver = {
> +	.probe		= dwc3_generic_probe,
> +	.remove		= dwc3_generic_remove,
> +	.driver		= {
> +		.name	= "dwc3-generic-plat",
> +		.of_match_table = dwc3_generic_of_match,
> +		.pm	= &dwc3_generic_dev_pm_ops,

You're still not using the new pm_ptr()/pm_sleep_ptr. The kernel build
bot will complain about the maybe unused functions.

BR,
Thinh

Re: [PATCH v5 2/2] usb: dwc3: add generic driver to support flattened

[Ze Huang]

On Fri, Jul 11, 2025 at 11:37:32PM +0000, Thinh Nguyen wrote:
> On Sat, Jul 05, 2025, Ze Huang wrote:
> > To support flattened dwc3 dt model and drop the glue layer, introduce the
> > `dwc3-generic` driver. This enables direct binding of the DWC3 core driver
> > and offers an alternative to the existing glue driver `dwc3-of-simple`.
> > 
> > Signed-off-by: Ze Huang <huang.ze@linux.dev>
> > ---
> >  drivers/usb/dwc3/Kconfig             |  11 +++
> >  drivers/usb/dwc3/Makefile            |   1 +
> >  drivers/usb/dwc3/dwc3-generic-plat.c | 182 +++++++++++++++++++++++++++++++++++
> >  3 files changed, 194 insertions(+)
> > 

[...]

> > +static const struct dev_pm_ops dwc3_generic_dev_pm_ops = {
> > +	SET_SYSTEM_SLEEP_PM_OPS(dwc3_generic_suspend, dwc3_generic_resume)
> > +	SET_RUNTIME_PM_OPS(dwc3_generic_runtime_suspend, dwc3_generic_runtime_resume,
> > +			   dwc3_generic_runtime_idle)
> > +};
> > +
> > +static const struct of_device_id dwc3_generic_of_match[] = {
> > +	{ .compatible = "spacemit,k1-dwc3", },
> > +	{ /* sentinel */ }
> > +};
> > +MODULE_DEVICE_TABLE(of, dwc3_generic_of_match);
> > +
> > +static struct platform_driver dwc3_generic_driver = {
> > +	.probe		= dwc3_generic_probe,
> > +	.remove		= dwc3_generic_remove,
> > +	.driver		= {
> > +		.name	= "dwc3-generic-plat",
> > +		.of_match_table = dwc3_generic_of_match,
> > +		.pm	= &dwc3_generic_dev_pm_ops,
> 
> You're still not using the new pm_ptr()/pm_sleep_ptr. The kernel build
> bot will complain about the maybe unused functions.

Thanks for your patience.

I found they are caused by using SET_RUNTIME_PM_OPS and SET_SYSTEM_SLEEP_PM_OPS macros.

I'll replace them with new RUNTIME_PM_OPS/SYSTEM_SLEEP_PM_OPS and wrap the
dwc3_generic_dev_pm_ops with pm_ptr()

> 
> BR,
> Thinh