[PATCH v15 0/6] usb: misc: Add onboard_usb_hub driver

[PATCH v15 0/6] usb: misc: Add onboard_usb_hub driver

[Matthias Kaehlcke]

This series adds:
- the onboard_usb_hub_driver
- glue in the xhci-plat driver to create and destroy the
  onboard_usb_hub platform devices if needed
- a device tree binding for the Realtek RTS5411 USB hub controller
- device tree changes that add RTS5411 entries for the QCA SC7180
  based boards trogdor and lazor
- a couple of stubs for platform device functions to avoid
  unresolved symbols with certain kernel configs

The main issue the driver addresses is that a USB hub needs to be
powered before it can be discovered. For discrete onboard hubs (an
example for such a hub is the Realtek RTS5411) this is often solved
by supplying the hub with an 'always-on' regulator, which is kind
of a hack. Some onboard hubs may require further initialization
steps, like changing the state of a GPIO or enabling a clock, which
requires even more hacks. This driver creates a platform device
representing the hub which performs the necessary initialization.
Currently it only supports switching on a single regulator, support
for multiple regulators or other actions can be added as needed.
Different initialization sequences can be supported based on the
compatible string.

Besides performing the initialization the driver can be configured
to power the hub off during system suspend. This can help to extend
battery life on battery powered devices which have no requirements
to keep the hub powered during suspend. The driver can also be
configured to leave the hub powered when a wakeup capable USB device
is connected when suspending, and power it off otherwise.

Changes in v15:
- adjusted dependencies of USB_DWC3_CORE to make sure it can only
  be enabled when at least one of USB_DWC3_HOST, USB_DWC3_GADGET
  or USB_DWC3_DUAL_ROLE is selectable

Changes in v14:
- rebased on top of v5.14-rc1
- dropped DT binding patch which landed in v5.13

Changes in v13:
- added patch "usb: Specify dependency on USB_XHCI_PLATFORM with
  'depends on'" to the series to avoid Kconfig conflicts
- added patch "arm64: defconfig: Explicitly enable USB_XHCI_PLATFORM"
  to the series to keep effective defconfig unchanged

Changes in v12:
- onboard_hub driver: use IS_ENABLED(CONFIG_USB_ONBOARD_HUB_MODULE)
  in onboard_hub.h to also check for the driver built as module
- onboard_hub_driver: include onboard_hub.h again to make sure there
  are prototype declarations for the public functions

Changes in v11:
- support multiple onboard hubs connected to the same parent
- don't include ‘onboard_hub.h’ from the onboard hub driver

Changes in v10:
- always use of_is_onboard_usb_hub() stub unless ONBOARD_USB_HUB=y/m
- keep 'regulator-boot-on' property for pp3300_hub

Changes in v9:
- added dependency on ONBOARD_USB_HUB (or !!ONBOARD_USB_HUB) to
  USB_PLATFORM_XHCI

Changes in v7:
- updated DT binding
- series rebased on qcom/arm64-for-5.13

Changes in v6:
- updated summary

Changes in v5:
- cover letter added

Matthias Kaehlcke (6):
  usb: misc: Add onboard_usb_hub driver
  of/platform: Add stubs for of_platform_device_create/destroy()
  arm64: defconfig: Explicitly enable USB_XHCI_PLATFORM
  usb: Specify dependencies on USB_XHCI_PLATFORM with 'depends on'
  usb: host: xhci-plat: Create platform device for onboard hubs in
    probe()
  arm64: dts: qcom: sc7180-trogdor: Add nodes for onboard USB hub

 .../sysfs-bus-platform-onboard-usb-hub        |   8 +
 MAINTAINERS                                   |   7 +
 .../boot/dts/qcom/sc7180-trogdor-lazor-r0.dts |  19 +-
 .../boot/dts/qcom/sc7180-trogdor-lazor-r1.dts |  12 +-
 .../arm64/boot/dts/qcom/sc7180-trogdor-r1.dts |  19 +-
 arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi  |  19 +-
 arch/arm64/configs/defconfig                  |   1 +
 drivers/usb/cdns3/Kconfig                     |   2 +-
 drivers/usb/dwc3/Kconfig                      |   5 +-
 drivers/usb/host/Kconfig                      |   5 +-
 drivers/usb/host/xhci-plat.c                  |   6 +
 drivers/usb/host/xhci.h                       |   2 +
 drivers/usb/misc/Kconfig                      |  17 +
 drivers/usb/misc/Makefile                     |   1 +
 drivers/usb/misc/onboard_usb_hub.c            | 497 ++++++++++++++++++
 include/linux/of_platform.h                   |  22 +-
 include/linux/usb/onboard_hub.h               |  18 +
 17 files changed, 621 insertions(+), 39 deletions(-)
 create mode 100644 Documentation/ABI/testing/sysfs-bus-platform-onboard-usb-hub
 create mode 100644 drivers/usb/misc/onboard_usb_hub.c
 create mode 100644 include/linux/usb/onboard_hub.h

-- 
2.32.0.432.gabb21c7263-goog

[PATCH v15 6/6] arm64: dts: qcom: sc7180-trogdor: Add nodes for onboard USB hub

[Matthias Kaehlcke]

Add nodes for the onboard USB hub on trogdor devices. Remove the
'always-on' property from the hub regulator, since the regulator
is now managed by the onboard_usb_hub driver.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
---

Changes in v15:
- none

Changes in v14:
- none

Changes in v13:
- none

Changes in v12:
- none

Changes in v11:
- rebased on qcom/arm64-for-5.14 (with the rest of the series)

Changes in v10:
- keep 'regulator-boot-on' property
- updated commit message

Changes in v9:
- none

Changes in v8:
- none

Changes in v7:
- rebased on qcom/arm64-for-5.13 (with the rest of the series)

Changes in v6:
- added 'companion-hub' entry to both USB devices
- added 'vdd-supply' also to hub@2

Changes in v5:
- patch added to the series

 .../boot/dts/qcom/sc7180-trogdor-lazor-r0.dts | 19 ++++++++-----------
 .../boot/dts/qcom/sc7180-trogdor-lazor-r1.dts | 12 +++++-------
 .../arm64/boot/dts/qcom/sc7180-trogdor-r1.dts | 19 ++++++++-----------
 arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi  | 19 ++++++++++++++++++-
 4 files changed, 39 insertions(+), 30 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor-lazor-r0.dts b/arch/arm64/boot/dts/qcom/sc7180-trogdor-lazor-r0.dts
index 30e3e769d2b4..5fb8e12af1a0 100644
--- a/arch/arm64/boot/dts/qcom/sc7180-trogdor-lazor-r0.dts
+++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor-lazor-r0.dts
@@ -14,17 +14,6 @@ / {
 	compatible = "google,lazor-rev0", "qcom,sc7180";
 };
 
-&pp3300_hub {
-	/* pp3300_l7c is used to power the USB hub */
-	/delete-property/regulator-always-on;
-	/delete-property/regulator-boot-on;
-};
-
-&pp3300_l7c {
-	regulator-always-on;
-	regulator-boot-on;
-};
-
 &sn65dsi86_out {
 	/*
 	 * Lane 0 was incorrectly mapped on the cable, but we've now decided
@@ -33,3 +22,11 @@ &sn65dsi86_out {
 	 */
 	lane-polarities = <1 0>;
 };
+
+&usb_hub_2_0 {
+	 vdd-supply = <&pp3300_l7c>;
+};
+
+&usb_hub_3_0 {
+	 vdd-supply = <&pp3300_l7c>;
+};
diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor-lazor-r1.dts b/arch/arm64/boot/dts/qcom/sc7180-trogdor-lazor-r1.dts
index c2ef06367baf..1dae714250f5 100644
--- a/arch/arm64/boot/dts/qcom/sc7180-trogdor-lazor-r1.dts
+++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor-lazor-r1.dts
@@ -14,13 +14,11 @@ / {
 	compatible = "google,lazor-rev1", "google,lazor-rev2", "qcom,sc7180";
 };
 
-&pp3300_hub {
-	/* pp3300_l7c is used to power the USB hub */
-	/delete-property/regulator-always-on;
-	/delete-property/regulator-boot-on;
+
+&usb_hub_2_0 {
+	 vdd-supply = <&pp3300_l7c>;
 };
 
-&pp3300_l7c {
-	regulator-always-on;
-	regulator-boot-on;
+&usb_hub_3_0 {
+	 vdd-supply = <&pp3300_l7c>;
 };
diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor-r1.dts b/arch/arm64/boot/dts/qcom/sc7180-trogdor-r1.dts
index 2b522f9e0d8f..2f5263e3d1b9 100644
--- a/arch/arm64/boot/dts/qcom/sc7180-trogdor-r1.dts
+++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor-r1.dts
@@ -42,17 +42,6 @@ &panel {
 	compatible = "auo,b116xa01";
 };
 
-&pp3300_hub {
-	/* pp3300_l7c is used to power the USB hub */
-	/delete-property/regulator-always-on;
-	/delete-property/regulator-boot-on;
-};
-
-&pp3300_l7c {
-	regulator-always-on;
-	regulator-boot-on;
-};
-
 &sdhc_2 {
 	status = "okay";
 };
@@ -61,6 +50,14 @@ &trackpad {
 	interrupts = <58 IRQ_TYPE_EDGE_FALLING>;
 };
 
+&usb_hub_2_0 {
+	 vdd-supply = <&pp3300_l7c>;
+};
+
+&usb_hub_3_0 {
+	 vdd-supply = <&pp3300_l7c>;
+};
+
 /* PINCTRL - modifications to sc7180-trogdor.dtsi */
 
 &trackpad_int_1v8_odl {
diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi
index 77ae7561d436..f89c6a7045e5 100644
--- a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi
+++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi
@@ -202,7 +202,6 @@ pp3300_hub: pp3300-hub {
 		pinctrl-names = "default";
 		pinctrl-0 = <&en_pp3300_hub>;
 
-		regulator-always-on;
 		regulator-boot-on;
 
 		vin-supply = <&pp3300_a>;
@@ -898,6 +897,24 @@ &usb_1 {
 
 &usb_1_dwc3 {
 	dr_mode = "host";
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	/* 2.0 hub on port 1 */
+	usb_hub_2_0: hub@1 {
+		compatible = "usbbda,5411";
+		reg = <1>;
+		vdd-supply = <&pp3300_hub>;
+		companion-hub = <&usb_hub_3_0>;
+	};
+
+	/* 3.0 hub on port 2 */
+	usb_hub_3_0: hub@2 {
+		compatible = "usbbda,411";
+		reg = <2>;
+		vdd-supply = <&pp3300_hub>;
+		companion-hub = <&usb_hub_2_0>;
+	};
 };
 
 &usb_1_hsphy {
-- 
2.32.0.432.gabb21c7263-goog

Re: [PATCH v15 0/6] usb: misc: Add onboard_usb_hub driver

[Matthias Kaehlcke]

Hi Greg,

Just wanted to check if this series is still on your radar. Is
there anything that blocks it from landing (further ACKs, ...)?

Thanks

Matthias

On Mon, Jul 26, 2021 at 05:41:12PM -0700, Matthias Kaehlcke wrote:
> This series adds:
> - the onboard_usb_hub_driver
> - glue in the xhci-plat driver to create and destroy the
>   onboard_usb_hub platform devices if needed
> - a device tree binding for the Realtek RTS5411 USB hub controller
> - device tree changes that add RTS5411 entries for the QCA SC7180
>   based boards trogdor and lazor
> - a couple of stubs for platform device functions to avoid
>   unresolved symbols with certain kernel configs
> 
> The main issue the driver addresses is that a USB hub needs to be
> powered before it can be discovered. For discrete onboard hubs (an
> example for such a hub is the Realtek RTS5411) this is often solved
> by supplying the hub with an 'always-on' regulator, which is kind
> of a hack. Some onboard hubs may require further initialization
> steps, like changing the state of a GPIO or enabling a clock, which
> requires even more hacks. This driver creates a platform device
> representing the hub which performs the necessary initialization.
> Currently it only supports switching on a single regulator, support
> for multiple regulators or other actions can be added as needed.
> Different initialization sequences can be supported based on the
> compatible string.
> 
> Besides performing the initialization the driver can be configured
> to power the hub off during system suspend. This can help to extend
> battery life on battery powered devices which have no requirements
> to keep the hub powered during suspend. The driver can also be
> configured to leave the hub powered when a wakeup capable USB device
> is connected when suspending, and power it off otherwise.
> 
> Changes in v15:
> - adjusted dependencies of USB_DWC3_CORE to make sure it can only
>   be enabled when at least one of USB_DWC3_HOST, USB_DWC3_GADGET
>   or USB_DWC3_DUAL_ROLE is selectable
> 
> Changes in v14:
> - rebased on top of v5.14-rc1
> - dropped DT binding patch which landed in v5.13
> 
> Changes in v13:
> - added patch "usb: Specify dependency on USB_XHCI_PLATFORM with
>   'depends on'" to the series to avoid Kconfig conflicts
> - added patch "arm64: defconfig: Explicitly enable USB_XHCI_PLATFORM"
>   to the series to keep effective defconfig unchanged
> 
> Changes in v12:
> - onboard_hub driver: use IS_ENABLED(CONFIG_USB_ONBOARD_HUB_MODULE)
>   in onboard_hub.h to also check for the driver built as module
> - onboard_hub_driver: include onboard_hub.h again to make sure there
>   are prototype declarations for the public functions
> 
> Changes in v11:
> - support multiple onboard hubs connected to the same parent
> - don't include ‘onboard_hub.h’ from the onboard hub driver
> 
> Changes in v10:
> - always use of_is_onboard_usb_hub() stub unless ONBOARD_USB_HUB=y/m
> - keep 'regulator-boot-on' property for pp3300_hub
> 
> Changes in v9:
> - added dependency on ONBOARD_USB_HUB (or !!ONBOARD_USB_HUB) to
>   USB_PLATFORM_XHCI
> 
> Changes in v7:
> - updated DT binding
> - series rebased on qcom/arm64-for-5.13
> 
> Changes in v6:
> - updated summary
> 
> Changes in v5:
> - cover letter added
> 
> Matthias Kaehlcke (6):
>   usb: misc: Add onboard_usb_hub driver
>   of/platform: Add stubs for of_platform_device_create/destroy()
>   arm64: defconfig: Explicitly enable USB_XHCI_PLATFORM
>   usb: Specify dependencies on USB_XHCI_PLATFORM with 'depends on'
>   usb: host: xhci-plat: Create platform device for onboard hubs in
>     probe()
>   arm64: dts: qcom: sc7180-trogdor: Add nodes for onboard USB hub
> 
>  .../sysfs-bus-platform-onboard-usb-hub        |   8 +
>  MAINTAINERS                                   |   7 +
>  .../boot/dts/qcom/sc7180-trogdor-lazor-r0.dts |  19 +-
>  .../boot/dts/qcom/sc7180-trogdor-lazor-r1.dts |  12 +-
>  .../arm64/boot/dts/qcom/sc7180-trogdor-r1.dts |  19 +-
>  arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi  |  19 +-
>  arch/arm64/configs/defconfig                  |   1 +
>  drivers/usb/cdns3/Kconfig                     |   2 +-
>  drivers/usb/dwc3/Kconfig                      |   5 +-
>  drivers/usb/host/Kconfig                      |   5 +-
>  drivers/usb/host/xhci-plat.c                  |   6 +
>  drivers/usb/host/xhci.h                       |   2 +
>  drivers/usb/misc/Kconfig                      |  17 +
>  drivers/usb/misc/Makefile                     |   1 +
>  drivers/usb/misc/onboard_usb_hub.c            | 497 ++++++++++++++++++
>  include/linux/of_platform.h                   |  22 +-
>  include/linux/usb/onboard_hub.h               |  18 +
>  17 files changed, 621 insertions(+), 39 deletions(-)
>  create mode 100644 Documentation/ABI/testing/sysfs-bus-platform-onboard-usb-hub
>  create mode 100644 drivers/usb/misc/onboard_usb_hub.c
>  create mode 100644 include/linux/usb/onboard_hub.h
> 
> -- 
> 2.32.0.432.gabb21c7263-goog
> 

Re: [PATCH v15 0/6] usb: misc: Add onboard_usb_hub driver

[Roger Quadros]

Hi Matthias,

On 09/08/2021 18:49, Matthias Kaehlcke wrote:
> Hi Greg,
> 
> Just wanted to check if this series is still on your radar. Is
> there anything that blocks it from landing (further ACKs, ...)?
> 
> Thanks
> 
> Matthias
> 
> On Mon, Jul 26, 2021 at 05:41:12PM -0700, Matthias Kaehlcke wrote:
>> This series adds:
>> - the onboard_usb_hub_driver
>> - glue in the xhci-plat driver to create and destroy the
>>   onboard_usb_hub platform devices if needed
>> - a device tree binding for the Realtek RTS5411 USB hub controller
>> - device tree changes that add RTS5411 entries for the QCA SC7180
>>   based boards trogdor and lazor
>> - a couple of stubs for platform device functions to avoid
>>   unresolved symbols with certain kernel configs
>>
>> The main issue the driver addresses is that a USB hub needs to be
>> powered before it can be discovered. For discrete onboard hubs (an
>> example for such a hub is the Realtek RTS5411) this is often solved
>> by supplying the hub with an 'always-on' regulator, which is kind
>> of a hack. Some onboard hubs may require further initialization
>> steps, like changing the state of a GPIO or enabling a clock, which
>> requires even more hacks. This driver creates a platform device
>> representing the hub which performs the necessary initialization.
>> Currently it only supports switching on a single regulator, support
>> for multiple regulators or other actions can be added as needed.
>> Different initialization sequences can be supported based on the
>> compatible string.
>>
>> Besides performing the initialization the driver can be configured
>> to power the hub off during system suspend. This can help to extend
>> battery life on battery powered devices which have no requirements
>> to keep the hub powered during suspend. The driver can also be
>> configured to leave the hub powered when a wakeup capable USB device
>> is connected when suspending, and power it off otherwise.
>>
>> Changes in v15:
>> - adjusted dependencies of USB_DWC3_CORE to make sure it can only
>>   be enabled when at least one of USB_DWC3_HOST, USB_DWC3_GADGET
>>   or USB_DWC3_DUAL_ROLE is selectable
>>
>> Changes in v14:
>> - rebased on top of v5.14-rc1
>> - dropped DT binding patch which landed in v5.13
>>
>> Changes in v13:
>> - added patch "usb: Specify dependency on USB_XHCI_PLATFORM with
>>   'depends on'" to the series to avoid Kconfig conflicts
>> - added patch "arm64: defconfig: Explicitly enable USB_XHCI_PLATFORM"
>>   to the series to keep effective defconfig unchanged
>>
>> Changes in v12:
>> - onboard_hub driver: use IS_ENABLED(CONFIG_USB_ONBOARD_HUB_MODULE)
>>   in onboard_hub.h to also check for the driver built as module
>> - onboard_hub_driver: include onboard_hub.h again to make sure there
>>   are prototype declarations for the public functions
>>
>> Changes in v11:
>> - support multiple onboard hubs connected to the same parent
>> - don't include ‘onboard_hub.h’ from the onboard hub driver
>>
>> Changes in v10:
>> - always use of_is_onboard_usb_hub() stub unless ONBOARD_USB_HUB=y/m
>> - keep 'regulator-boot-on' property for pp3300_hub
>>
>> Changes in v9:
>> - added dependency on ONBOARD_USB_HUB (or !!ONBOARD_USB_HUB) to
>>   USB_PLATFORM_XHCI
>>
>> Changes in v7:
>> - updated DT binding
>> - series rebased on qcom/arm64-for-5.13
>>
>> Changes in v6:
>> - updated summary
>>
>> Changes in v5:
>> - cover letter added
>>
>> Matthias Kaehlcke (6):
>>   usb: misc: Add onboard_usb_hub driver
>>   of/platform: Add stubs for of_platform_device_create/destroy()
>>   arm64: defconfig: Explicitly enable USB_XHCI_PLATFORM
>>   usb: Specify dependencies on USB_XHCI_PLATFORM with 'depends on'
>>   usb: host: xhci-plat: Create platform device for onboard hubs in
>>     probe()
>>   arm64: dts: qcom: sc7180-trogdor: Add nodes for onboard USB hub
>>
>>  .../sysfs-bus-platform-onboard-usb-hub        |   8 +
>>  MAINTAINERS                                   |   7 +
>>  .../boot/dts/qcom/sc7180-trogdor-lazor-r0.dts |  19 +-
>>  .../boot/dts/qcom/sc7180-trogdor-lazor-r1.dts |  12 +-
>>  .../arm64/boot/dts/qcom/sc7180-trogdor-r1.dts |  19 +-
>>  arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi  |  19 +-
>>  arch/arm64/configs/defconfig                  |   1 +
>>  drivers/usb/cdns3/Kconfig                     |   2 +-
>>  drivers/usb/dwc3/Kconfig                      |   5 +-
>>  drivers/usb/host/Kconfig                      |   5 +-

These Kconfig changes are causing the resulting .config to be different.
For example, if I start with omap2plus_defconfig, the resulting .config
before and after your series is different as shown below

:/work/linux$ diff /tmp/.config .config
1902d1901
< # CONFIG_HISI_HIKEY_USB is not set
4992c4991
< CONFIG_USB_XHCI_PLATFORM=m
---
> # CONFIG_USB_XHCI_PLATFORM is not set
5073,5075c5072
< # CONFIG_USB_DWC3_HOST is not set
< # CONFIG_USB_DWC3_GADGET is not set
< CONFIG_USB_DWC3_DUAL_ROLE=y
---
> CONFIG_USB_DWC3_GADGET=y
5173a5171
> # CONFIG_USB_ONBOARD_HUB is not set
5285c5283
< CONFIG_USB_ROLE_SWITCH=m
---
> # CONFIG_USB_ROLE_SWITCH is not set

I would expect the same issues for multi_v7_defconfig and multi_v8_defconfig as well.
I'm ok to update the relevant defconfigs files so that the resulting .config is identical to
before your series. Thanks!

--
cheers,
-roger

Re: [PATCH v15 0/6] usb: misc: Add onboard_usb_hub driver

[Roger Quadros]

On 11/08/2021 15:38, Roger Quadros wrote:
> Hi Matthias,
> 
> On 09/08/2021 18:49, Matthias Kaehlcke wrote:
>> Hi Greg,
>>
>> Just wanted to check if this series is still on your radar. Is
>> there anything that blocks it from landing (further ACKs, ...)?
>>
>> Thanks
>>
>> Matthias
>>
>> On Mon, Jul 26, 2021 at 05:41:12PM -0700, Matthias Kaehlcke wrote:
>>> This series adds:
>>> - the onboard_usb_hub_driver
>>> - glue in the xhci-plat driver to create and destroy the
>>>   onboard_usb_hub platform devices if needed
>>> - a device tree binding for the Realtek RTS5411 USB hub controller
>>> - device tree changes that add RTS5411 entries for the QCA SC7180
>>>   based boards trogdor and lazor
>>> - a couple of stubs for platform device functions to avoid
>>>   unresolved symbols with certain kernel configs
>>>
>>> The main issue the driver addresses is that a USB hub needs to be
>>> powered before it can be discovered. For discrete onboard hubs (an
>>> example for such a hub is the Realtek RTS5411) this is often solved
>>> by supplying the hub with an 'always-on' regulator, which is kind
>>> of a hack. Some onboard hubs may require further initialization
>>> steps, like changing the state of a GPIO or enabling a clock, which
>>> requires even more hacks. This driver creates a platform device
>>> representing the hub which performs the necessary initialization.
>>> Currently it only supports switching on a single regulator, support
>>> for multiple regulators or other actions can be added as needed.
>>> Different initialization sequences can be supported based on the
>>> compatible string.
>>>
>>> Besides performing the initialization the driver can be configured
>>> to power the hub off during system suspend. This can help to extend
>>> battery life on battery powered devices which have no requirements
>>> to keep the hub powered during suspend. The driver can also be
>>> configured to leave the hub powered when a wakeup capable USB device
>>> is connected when suspending, and power it off otherwise.
>>>
>>> Changes in v15:
>>> - adjusted dependencies of USB_DWC3_CORE to make sure it can only
>>>   be enabled when at least one of USB_DWC3_HOST, USB_DWC3_GADGET
>>>   or USB_DWC3_DUAL_ROLE is selectable
>>>
>>> Changes in v14:
>>> - rebased on top of v5.14-rc1
>>> - dropped DT binding patch which landed in v5.13
>>>
>>> Changes in v13:
>>> - added patch "usb: Specify dependency on USB_XHCI_PLATFORM with
>>>   'depends on'" to the series to avoid Kconfig conflicts
>>> - added patch "arm64: defconfig: Explicitly enable USB_XHCI_PLATFORM"
>>>   to the series to keep effective defconfig unchanged
>>>
>>> Changes in v12:
>>> - onboard_hub driver: use IS_ENABLED(CONFIG_USB_ONBOARD_HUB_MODULE)
>>>   in onboard_hub.h to also check for the driver built as module
>>> - onboard_hub_driver: include onboard_hub.h again to make sure there
>>>   are prototype declarations for the public functions
>>>
>>> Changes in v11:
>>> - support multiple onboard hubs connected to the same parent
>>> - don't include ‘onboard_hub.h’ from the onboard hub driver
>>>
>>> Changes in v10:
>>> - always use of_is_onboard_usb_hub() stub unless ONBOARD_USB_HUB=y/m
>>> - keep 'regulator-boot-on' property for pp3300_hub
>>>
>>> Changes in v9:
>>> - added dependency on ONBOARD_USB_HUB (or !!ONBOARD_USB_HUB) to
>>>   USB_PLATFORM_XHCI
>>>
>>> Changes in v7:
>>> - updated DT binding
>>> - series rebased on qcom/arm64-for-5.13
>>>
>>> Changes in v6:
>>> - updated summary
>>>
>>> Changes in v5:
>>> - cover letter added
>>>
>>> Matthias Kaehlcke (6):
>>>   usb: misc: Add onboard_usb_hub driver
>>>   of/platform: Add stubs for of_platform_device_create/destroy()
>>>   arm64: defconfig: Explicitly enable USB_XHCI_PLATFORM
>>>   usb: Specify dependencies on USB_XHCI_PLATFORM with 'depends on'
>>>   usb: host: xhci-plat: Create platform device for onboard hubs in
>>>     probe()
>>>   arm64: dts: qcom: sc7180-trogdor: Add nodes for onboard USB hub
>>>
>>>  .../sysfs-bus-platform-onboard-usb-hub        |   8 +
>>>  MAINTAINERS                                   |   7 +
>>>  .../boot/dts/qcom/sc7180-trogdor-lazor-r0.dts |  19 +-
>>>  .../boot/dts/qcom/sc7180-trogdor-lazor-r1.dts |  12 +-
>>>  .../arm64/boot/dts/qcom/sc7180-trogdor-r1.dts |  19 +-
>>>  arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi  |  19 +-
>>>  arch/arm64/configs/defconfig                  |   1 +
>>>  drivers/usb/cdns3/Kconfig                     |   2 +-
>>>  drivers/usb/dwc3/Kconfig                      |   5 +-
>>>  drivers/usb/host/Kconfig                      |   5 +-
> 
> These Kconfig changes are causing the resulting .config to be different.
> For example, if I start with omap2plus_defconfig, the resulting .config
> before and after your series is different as shown below
> 
> :/work/linux$ diff /tmp/.config .config
> 1902d1901
> < # CONFIG_HISI_HIKEY_USB is not set
> 4992c4991
> < CONFIG_USB_XHCI_PLATFORM=m
> ---
>> # CONFIG_USB_XHCI_PLATFORM is not set
> 5073,5075c5072
> < # CONFIG_USB_DWC3_HOST is not set
> < # CONFIG_USB_DWC3_GADGET is not set
> < CONFIG_USB_DWC3_DUAL_ROLE=y
> ---
>> CONFIG_USB_DWC3_GADGET=y
> 5173a5171
>> # CONFIG_USB_ONBOARD_HUB is not set
> 5285c5283
> < CONFIG_USB_ROLE_SWITCH=m
> ---
>> # CONFIG_USB_ROLE_SWITCH is not set
> 
> I would expect the same issues for multi_v7_defconfig and multi_v8_defconfig as well.

Sorry I meant defconfig for arm64, not multi_v8_defconfig.

I checked that for arm64 defconfig it is ok.

> I'm ok to update the relevant defconfigs files so that the resulting .config is identical to
> before your series. Thanks!

With the below patch you can fix it for omap2plus_defconfig and multi_v7_defconfig.

diff --git a/arch/arm/configs/multi_v7_defconfig b/arch/arm/configs/multi_v7_defconfig
index d9abaae118dd..8c175ab37377 100644
--- a/arch/arm/configs/multi_v7_defconfig
+++ b/arch/arm/configs/multi_v7_defconfig
@@ -787,6 +787,7 @@ CONFIG_SND_AUDIO_GRAPH_CARD=m
 CONFIG_USB=y
 CONFIG_USB_OTG=y
 CONFIG_USB_XHCI_HCD=y
+CONFIG_USB_XHCI_PLATFORM=y
 CONFIG_USB_XHCI_MVEBU=y
 CONFIG_USB_XHCI_TEGRA=m
 CONFIG_USB_EHCI_HCD=y
diff --git a/arch/arm/configs/omap2plus_defconfig b/arch/arm/configs/omap2plus_defconfig
index 2ac2418084ab..a015fb04fa25 100644
--- a/arch/arm/configs/omap2plus_defconfig
+++ b/arch/arm/configs/omap2plus_defconfig
@@ -562,6 +562,7 @@ CONFIG_USB=m
 CONFIG_USB_ANNOUNCE_NEW_DEVICES=y
 CONFIG_USB_MON=m
 CONFIG_USB_XHCI_HCD=m
+CONFIG_USB_XHCI_PLATFORM=m
 CONFIG_USB_EHCI_HCD=m
 CONFIG_USB_OHCI_HCD=m
 CONFIG_USB_ACM=m

--
cheers,
-roger

Re: [PATCH v15 0/6] usb: misc: Add onboard_usb_hub driver

[Matthias Kaehlcke]

Hi Roger,

On Wed, Aug 11, 2021 at 03:56:15PM +0300, Roger Quadros wrote:
> 
> 
> On 11/08/2021 15:38, Roger Quadros wrote:
> > Hi Matthias,
> > 
> > On 09/08/2021 18:49, Matthias Kaehlcke wrote:
> >> Hi Greg,
> >>
> >> Just wanted to check if this series is still on your radar. Is
> >> there anything that blocks it from landing (further ACKs, ...)?
> >>
> >> Thanks
> >>
> >> Matthias
> >>
> >> On Mon, Jul 26, 2021 at 05:41:12PM -0700, Matthias Kaehlcke wrote:
> >>> This series adds:
> >>> - the onboard_usb_hub_driver
> >>> - glue in the xhci-plat driver to create and destroy the
> >>>   onboard_usb_hub platform devices if needed
> >>> - a device tree binding for the Realtek RTS5411 USB hub controller
> >>> - device tree changes that add RTS5411 entries for the QCA SC7180
> >>>   based boards trogdor and lazor
> >>> - a couple of stubs for platform device functions to avoid
> >>>   unresolved symbols with certain kernel configs
> >>>
> >>> The main issue the driver addresses is that a USB hub needs to be
> >>> powered before it can be discovered. For discrete onboard hubs (an
> >>> example for such a hub is the Realtek RTS5411) this is often solved
> >>> by supplying the hub with an 'always-on' regulator, which is kind
> >>> of a hack. Some onboard hubs may require further initialization
> >>> steps, like changing the state of a GPIO or enabling a clock, which
> >>> requires even more hacks. This driver creates a platform device
> >>> representing the hub which performs the necessary initialization.
> >>> Currently it only supports switching on a single regulator, support
> >>> for multiple regulators or other actions can be added as needed.
> >>> Different initialization sequences can be supported based on the
> >>> compatible string.
> >>>
> >>> Besides performing the initialization the driver can be configured
> >>> to power the hub off during system suspend. This can help to extend
> >>> battery life on battery powered devices which have no requirements
> >>> to keep the hub powered during suspend. The driver can also be
> >>> configured to leave the hub powered when a wakeup capable USB device
> >>> is connected when suspending, and power it off otherwise.
> >>>
> >>> Changes in v15:
> >>> - adjusted dependencies of USB_DWC3_CORE to make sure it can only
> >>>   be enabled when at least one of USB_DWC3_HOST, USB_DWC3_GADGET
> >>>   or USB_DWC3_DUAL_ROLE is selectable
> >>>
> >>> Changes in v14:
> >>> - rebased on top of v5.14-rc1
> >>> - dropped DT binding patch which landed in v5.13
> >>>
> >>> Changes in v13:
> >>> - added patch "usb: Specify dependency on USB_XHCI_PLATFORM with
> >>>   'depends on'" to the series to avoid Kconfig conflicts
> >>> - added patch "arm64: defconfig: Explicitly enable USB_XHCI_PLATFORM"
> >>>   to the series to keep effective defconfig unchanged
> >>>
> >>> Changes in v12:
> >>> - onboard_hub driver: use IS_ENABLED(CONFIG_USB_ONBOARD_HUB_MODULE)
> >>>   in onboard_hub.h to also check for the driver built as module
> >>> - onboard_hub_driver: include onboard_hub.h again to make sure there
> >>>   are prototype declarations for the public functions
> >>>
> >>> Changes in v11:
> >>> - support multiple onboard hubs connected to the same parent
> >>> - don't include ‘onboard_hub.h’ from the onboard hub driver
> >>>
> >>> Changes in v10:
> >>> - always use of_is_onboard_usb_hub() stub unless ONBOARD_USB_HUB=y/m
> >>> - keep 'regulator-boot-on' property for pp3300_hub
> >>>
> >>> Changes in v9:
> >>> - added dependency on ONBOARD_USB_HUB (or !!ONBOARD_USB_HUB) to
> >>>   USB_PLATFORM_XHCI
> >>>
> >>> Changes in v7:
> >>> - updated DT binding
> >>> - series rebased on qcom/arm64-for-5.13
> >>>
> >>> Changes in v6:
> >>> - updated summary
> >>>
> >>> Changes in v5:
> >>> - cover letter added
> >>>
> >>> Matthias Kaehlcke (6):
> >>>   usb: misc: Add onboard_usb_hub driver
> >>>   of/platform: Add stubs for of_platform_device_create/destroy()
> >>>   arm64: defconfig: Explicitly enable USB_XHCI_PLATFORM
> >>>   usb: Specify dependencies on USB_XHCI_PLATFORM with 'depends on'
> >>>   usb: host: xhci-plat: Create platform device for onboard hubs in
> >>>     probe()
> >>>   arm64: dts: qcom: sc7180-trogdor: Add nodes for onboard USB hub
> >>>
> >>>  .../sysfs-bus-platform-onboard-usb-hub        |   8 +
> >>>  MAINTAINERS                                   |   7 +
> >>>  .../boot/dts/qcom/sc7180-trogdor-lazor-r0.dts |  19 +-
> >>>  .../boot/dts/qcom/sc7180-trogdor-lazor-r1.dts |  12 +-
> >>>  .../arm64/boot/dts/qcom/sc7180-trogdor-r1.dts |  19 +-
> >>>  arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi  |  19 +-
> >>>  arch/arm64/configs/defconfig                  |   1 +
> >>>  drivers/usb/cdns3/Kconfig                     |   2 +-
> >>>  drivers/usb/dwc3/Kconfig                      |   5 +-
> >>>  drivers/usb/host/Kconfig                      |   5 +-
> > 
> > These Kconfig changes are causing the resulting .config to be different.
> > For example, if I start with omap2plus_defconfig, the resulting .config
> > before and after your series is different as shown below
> > 
> > :/work/linux$ diff /tmp/.config .config
> > 1902d1901
> > < # CONFIG_HISI_HIKEY_USB is not set
> > 4992c4991
> > < CONFIG_USB_XHCI_PLATFORM=m
> > ---
> >> # CONFIG_USB_XHCI_PLATFORM is not set
> > 5073,5075c5072
> > < # CONFIG_USB_DWC3_HOST is not set
> > < # CONFIG_USB_DWC3_GADGET is not set
> > < CONFIG_USB_DWC3_DUAL_ROLE=y
> > ---
> >> CONFIG_USB_DWC3_GADGET=y
> > 5173a5171
> >> # CONFIG_USB_ONBOARD_HUB is not set
> > 5285c5283
> > < CONFIG_USB_ROLE_SWITCH=m
> > ---
> >> # CONFIG_USB_ROLE_SWITCH is not set
> > 
> > I would expect the same issues for multi_v7_defconfig and multi_v8_defconfig as well.
> 
> Sorry I meant defconfig for arm64, not multi_v8_defconfig.
> 
> I checked that for arm64 defconfig it is ok.
> 
> > I'm ok to update the relevant defconfigs files so that the resulting .config is identical to
> > before your series. Thanks!
> 
> With the below patch you can fix it for omap2plus_defconfig and multi_v7_defconfig.
> 
> diff --git a/arch/arm/configs/multi_v7_defconfig b/arch/arm/configs/multi_v7_defconfig
> index d9abaae118dd..8c175ab37377 100644
> --- a/arch/arm/configs/multi_v7_defconfig
> +++ b/arch/arm/configs/multi_v7_defconfig
> @@ -787,6 +787,7 @@ CONFIG_SND_AUDIO_GRAPH_CARD=m
>  CONFIG_USB=y
>  CONFIG_USB_OTG=y
>  CONFIG_USB_XHCI_HCD=y
> +CONFIG_USB_XHCI_PLATFORM=y
>  CONFIG_USB_XHCI_MVEBU=y
>  CONFIG_USB_XHCI_TEGRA=m
>  CONFIG_USB_EHCI_HCD=y
> diff --git a/arch/arm/configs/omap2plus_defconfig b/arch/arm/configs/omap2plus_defconfig
> index 2ac2418084ab..a015fb04fa25 100644
> --- a/arch/arm/configs/omap2plus_defconfig
> +++ b/arch/arm/configs/omap2plus_defconfig
> @@ -562,6 +562,7 @@ CONFIG_USB=m
>  CONFIG_USB_ANNOUNCE_NEW_DEVICES=y
>  CONFIG_USB_MON=m
>  CONFIG_USB_XHCI_HCD=m
> +CONFIG_USB_XHCI_PLATFORM=m
>  CONFIG_USB_EHCI_HCD=m
>  CONFIG_USB_OHCI_HCD=m
>  CONFIG_USB_ACM=m

Thanks for testing!

I completely forgot that arm32 has all these different defconfigs.

While trying to adjust qcom_defconfig I came across something that confuses
me. The original defconfig results in:

# CONFIG_USB_XHCI_HCD is not set
CONFIG_USB_DWC3_DUAL_ROLE=y

My assumption was that xHCI support is need for dwc3 dual mode (which is
made explicit by https://lore.kernel.org/patchwork/patch/1468240/), is
that incorrect? Maybe without xHCI support the controller can still
operate in USB 2.0 dual role mode?

Re: [PATCH v15 0/6] usb: misc: Add onboard_usb_hub driver

[Roger Quadros]

Hi Matthias,

On 12/08/2021 20:08, Matthias Kaehlcke wrote:
> Hi Roger,
> 
> On Wed, Aug 11, 2021 at 03:56:15PM +0300, Roger Quadros wrote:
>>
>>
>> On 11/08/2021 15:38, Roger Quadros wrote:
>>> Hi Matthias,
>>>
>>> On 09/08/2021 18:49, Matthias Kaehlcke wrote:
>>>> Hi Greg,
>>>>
>>>> Just wanted to check if this series is still on your radar. Is
>>>> there anything that blocks it from landing (further ACKs, ...)?
>>>>
>>>> Thanks
>>>>
>>>> Matthias
>>>>
>>>> On Mon, Jul 26, 2021 at 05:41:12PM -0700, Matthias Kaehlcke wrote:
>>>>> This series adds:
>>>>> - the onboard_usb_hub_driver
>>>>> - glue in the xhci-plat driver to create and destroy the
>>>>>   onboard_usb_hub platform devices if needed
>>>>> - a device tree binding for the Realtek RTS5411 USB hub controller
>>>>> - device tree changes that add RTS5411 entries for the QCA SC7180
>>>>>   based boards trogdor and lazor
>>>>> - a couple of stubs for platform device functions to avoid
>>>>>   unresolved symbols with certain kernel configs
>>>>>
>>>>> The main issue the driver addresses is that a USB hub needs to be
>>>>> powered before it can be discovered. For discrete onboard hubs (an
>>>>> example for such a hub is the Realtek RTS5411) this is often solved
>>>>> by supplying the hub with an 'always-on' regulator, which is kind
>>>>> of a hack. Some onboard hubs may require further initialization
>>>>> steps, like changing the state of a GPIO or enabling a clock, which
>>>>> requires even more hacks. This driver creates a platform device
>>>>> representing the hub which performs the necessary initialization.
>>>>> Currently it only supports switching on a single regulator, support
>>>>> for multiple regulators or other actions can be added as needed.
>>>>> Different initialization sequences can be supported based on the
>>>>> compatible string.
>>>>>
>>>>> Besides performing the initialization the driver can be configured
>>>>> to power the hub off during system suspend. This can help to extend
>>>>> battery life on battery powered devices which have no requirements
>>>>> to keep the hub powered during suspend. The driver can also be
>>>>> configured to leave the hub powered when a wakeup capable USB device
>>>>> is connected when suspending, and power it off otherwise.
>>>>>
>>>>> Changes in v15:
>>>>> - adjusted dependencies of USB_DWC3_CORE to make sure it can only
>>>>>   be enabled when at least one of USB_DWC3_HOST, USB_DWC3_GADGET
>>>>>   or USB_DWC3_DUAL_ROLE is selectable
>>>>>
>>>>> Changes in v14:
>>>>> - rebased on top of v5.14-rc1
>>>>> - dropped DT binding patch which landed in v5.13
>>>>>
>>>>> Changes in v13:
>>>>> - added patch "usb: Specify dependency on USB_XHCI_PLATFORM with
>>>>>   'depends on'" to the series to avoid Kconfig conflicts
>>>>> - added patch "arm64: defconfig: Explicitly enable USB_XHCI_PLATFORM"
>>>>>   to the series to keep effective defconfig unchanged
>>>>>
>>>>> Changes in v12:
>>>>> - onboard_hub driver: use IS_ENABLED(CONFIG_USB_ONBOARD_HUB_MODULE)
>>>>>   in onboard_hub.h to also check for the driver built as module
>>>>> - onboard_hub_driver: include onboard_hub.h again to make sure there
>>>>>   are prototype declarations for the public functions
>>>>>
>>>>> Changes in v11:
>>>>> - support multiple onboard hubs connected to the same parent
>>>>> - don't include ‘onboard_hub.h’ from the onboard hub driver
>>>>>
>>>>> Changes in v10:
>>>>> - always use of_is_onboard_usb_hub() stub unless ONBOARD_USB_HUB=y/m
>>>>> - keep 'regulator-boot-on' property for pp3300_hub
>>>>>
>>>>> Changes in v9:
>>>>> - added dependency on ONBOARD_USB_HUB (or !!ONBOARD_USB_HUB) to
>>>>>   USB_PLATFORM_XHCI
>>>>>
>>>>> Changes in v7:
>>>>> - updated DT binding
>>>>> - series rebased on qcom/arm64-for-5.13
>>>>>
>>>>> Changes in v6:
>>>>> - updated summary
>>>>>
>>>>> Changes in v5:
>>>>> - cover letter added
>>>>>
>>>>> Matthias Kaehlcke (6):
>>>>>   usb: misc: Add onboard_usb_hub driver
>>>>>   of/platform: Add stubs for of_platform_device_create/destroy()
>>>>>   arm64: defconfig: Explicitly enable USB_XHCI_PLATFORM
>>>>>   usb: Specify dependencies on USB_XHCI_PLATFORM with 'depends on'
>>>>>   usb: host: xhci-plat: Create platform device for onboard hubs in
>>>>>     probe()
>>>>>   arm64: dts: qcom: sc7180-trogdor: Add nodes for onboard USB hub
>>>>>
>>>>>  .../sysfs-bus-platform-onboard-usb-hub        |   8 +
>>>>>  MAINTAINERS                                   |   7 +
>>>>>  .../boot/dts/qcom/sc7180-trogdor-lazor-r0.dts |  19 +-
>>>>>  .../boot/dts/qcom/sc7180-trogdor-lazor-r1.dts |  12 +-
>>>>>  .../arm64/boot/dts/qcom/sc7180-trogdor-r1.dts |  19 +-
>>>>>  arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi  |  19 +-
>>>>>  arch/arm64/configs/defconfig                  |   1 +
>>>>>  drivers/usb/cdns3/Kconfig                     |   2 +-
>>>>>  drivers/usb/dwc3/Kconfig                      |   5 +-
>>>>>  drivers/usb/host/Kconfig                      |   5 +-
>>>
>>> These Kconfig changes are causing the resulting .config to be different.
>>> For example, if I start with omap2plus_defconfig, the resulting .config
>>> before and after your series is different as shown below
>>>
>>> :/work/linux$ diff /tmp/.config .config
>>> 1902d1901
>>> < # CONFIG_HISI_HIKEY_USB is not set
>>> 4992c4991
>>> < CONFIG_USB_XHCI_PLATFORM=m
>>> ---
>>>> # CONFIG_USB_XHCI_PLATFORM is not set
>>> 5073,5075c5072
>>> < # CONFIG_USB_DWC3_HOST is not set
>>> < # CONFIG_USB_DWC3_GADGET is not set
>>> < CONFIG_USB_DWC3_DUAL_ROLE=y
>>> ---
>>>> CONFIG_USB_DWC3_GADGET=y
>>> 5173a5171
>>>> # CONFIG_USB_ONBOARD_HUB is not set
>>> 5285c5283
>>> < CONFIG_USB_ROLE_SWITCH=m
>>> ---
>>>> # CONFIG_USB_ROLE_SWITCH is not set
>>>
>>> I would expect the same issues for multi_v7_defconfig and multi_v8_defconfig as well.
>>
>> Sorry I meant defconfig for arm64, not multi_v8_defconfig.
>>
>> I checked that for arm64 defconfig it is ok.
>>
>>> I'm ok to update the relevant defconfigs files so that the resulting .config is identical to
>>> before your series. Thanks!
>>
>> With the below patch you can fix it for omap2plus_defconfig and multi_v7_defconfig.
>>
>> diff --git a/arch/arm/configs/multi_v7_defconfig b/arch/arm/configs/multi_v7_defconfig
>> index d9abaae118dd..8c175ab37377 100644
>> --- a/arch/arm/configs/multi_v7_defconfig
>> +++ b/arch/arm/configs/multi_v7_defconfig
>> @@ -787,6 +787,7 @@ CONFIG_SND_AUDIO_GRAPH_CARD=m
>>  CONFIG_USB=y
>>  CONFIG_USB_OTG=y
>>  CONFIG_USB_XHCI_HCD=y
>> +CONFIG_USB_XHCI_PLATFORM=y
>>  CONFIG_USB_XHCI_MVEBU=y
>>  CONFIG_USB_XHCI_TEGRA=m
>>  CONFIG_USB_EHCI_HCD=y
>> diff --git a/arch/arm/configs/omap2plus_defconfig b/arch/arm/configs/omap2plus_defconfig
>> index 2ac2418084ab..a015fb04fa25 100644
>> --- a/arch/arm/configs/omap2plus_defconfig
>> +++ b/arch/arm/configs/omap2plus_defconfig
>> @@ -562,6 +562,7 @@ CONFIG_USB=m
>>  CONFIG_USB_ANNOUNCE_NEW_DEVICES=y
>>  CONFIG_USB_MON=m
>>  CONFIG_USB_XHCI_HCD=m
>> +CONFIG_USB_XHCI_PLATFORM=m
>>  CONFIG_USB_EHCI_HCD=m
>>  CONFIG_USB_OHCI_HCD=m
>>  CONFIG_USB_ACM=m
> 
> Thanks for testing!
> 
> I completely forgot that arm32 has all these different defconfigs.
> 
> While trying to adjust qcom_defconfig I came across something that confuses
> me. The original defconfig results in:
> 
> # CONFIG_USB_XHCI_HCD is not set
> CONFIG_USB_DWC3_DUAL_ROLE=y

The original Kconfig was:

> config USB_DWC3_DUAL_ROLE
>         bool "Dual Role mode"
>         depends on ((USB=y || USB=USB_DWC3) && (USB_GADGET=y || USB_GADGET=USB_DWC3))
>         depends on (EXTCON=y || EXTCON=USB_DWC3)

Which means USB_DWC3_DUAL_ROLE can be enabled even without CONFIG_USB_XHCI_HCD.

All the dual role code does is add/remove the host/gadget controller platform devices.
It doesn't care whether there is a driver for it or not.
i.e. there is no build dependency on CONFIG_USB_XHCI_HCD.

> 
> My assumption was that xHCI support is need for dwc3 dual mode (which is
> made explicit by https://lore.kernel.org/patchwork/patch/1468240/), is
> that incorrect? Maybe without xHCI support the controller can still
> operate in USB 2.0 dual role mode?
> 

Without xHCI support the host functionality will not work at all on dwc3 dual role.
So I think your Kconfig changes for USB_DWC3_DUAL_ROLE to depend on USB_XHCI_PLATFORM
are correct.

cheers,
-roger

Re: [PATCH v15 0/6] usb: misc: Add onboard_usb_hub driver

[Matthias Kaehlcke]

On Fri, Aug 13, 2021 at 09:35:53AM +0300, Roger Quadros wrote:
> Hi Matthias,
> 
> On 12/08/2021 20:08, Matthias Kaehlcke wrote:
> > Hi Roger,
> > 
> > On Wed, Aug 11, 2021 at 03:56:15PM +0300, Roger Quadros wrote:
> >>
> >>
> >> On 11/08/2021 15:38, Roger Quadros wrote:
> >>> Hi Matthias,
> >>>
> >>> On 09/08/2021 18:49, Matthias Kaehlcke wrote:
> >>>> Hi Greg,
> >>>>
> >>>> Just wanted to check if this series is still on your radar. Is
> >>>> there anything that blocks it from landing (further ACKs, ...)?
> >>>>
> >>>> Thanks
> >>>>
> >>>> Matthias
> >>>>
> >>>> On Mon, Jul 26, 2021 at 05:41:12PM -0700, Matthias Kaehlcke wrote:
> >>>>> This series adds:
> >>>>> - the onboard_usb_hub_driver
> >>>>> - glue in the xhci-plat driver to create and destroy the
> >>>>>   onboard_usb_hub platform devices if needed
> >>>>> - a device tree binding for the Realtek RTS5411 USB hub controller
> >>>>> - device tree changes that add RTS5411 entries for the QCA SC7180
> >>>>>   based boards trogdor and lazor
> >>>>> - a couple of stubs for platform device functions to avoid
> >>>>>   unresolved symbols with certain kernel configs
> >>>>>
> >>>>> The main issue the driver addresses is that a USB hub needs to be
> >>>>> powered before it can be discovered. For discrete onboard hubs (an
> >>>>> example for such a hub is the Realtek RTS5411) this is often solved
> >>>>> by supplying the hub with an 'always-on' regulator, which is kind
> >>>>> of a hack. Some onboard hubs may require further initialization
> >>>>> steps, like changing the state of a GPIO or enabling a clock, which
> >>>>> requires even more hacks. This driver creates a platform device
> >>>>> representing the hub which performs the necessary initialization.
> >>>>> Currently it only supports switching on a single regulator, support
> >>>>> for multiple regulators or other actions can be added as needed.
> >>>>> Different initialization sequences can be supported based on the
> >>>>> compatible string.
> >>>>>
> >>>>> Besides performing the initialization the driver can be configured
> >>>>> to power the hub off during system suspend. This can help to extend
> >>>>> battery life on battery powered devices which have no requirements
> >>>>> to keep the hub powered during suspend. The driver can also be
> >>>>> configured to leave the hub powered when a wakeup capable USB device
> >>>>> is connected when suspending, and power it off otherwise.
> >>>>>
> >>>>> Changes in v15:
> >>>>> - adjusted dependencies of USB_DWC3_CORE to make sure it can only
> >>>>>   be enabled when at least one of USB_DWC3_HOST, USB_DWC3_GADGET
> >>>>>   or USB_DWC3_DUAL_ROLE is selectable
> >>>>>
> >>>>> Changes in v14:
> >>>>> - rebased on top of v5.14-rc1
> >>>>> - dropped DT binding patch which landed in v5.13
> >>>>>
> >>>>> Changes in v13:
> >>>>> - added patch "usb: Specify dependency on USB_XHCI_PLATFORM with
> >>>>>   'depends on'" to the series to avoid Kconfig conflicts
> >>>>> - added patch "arm64: defconfig: Explicitly enable USB_XHCI_PLATFORM"
> >>>>>   to the series to keep effective defconfig unchanged
> >>>>>
> >>>>> Changes in v12:
> >>>>> - onboard_hub driver: use IS_ENABLED(CONFIG_USB_ONBOARD_HUB_MODULE)
> >>>>>   in onboard_hub.h to also check for the driver built as module
> >>>>> - onboard_hub_driver: include onboard_hub.h again to make sure there
> >>>>>   are prototype declarations for the public functions
> >>>>>
> >>>>> Changes in v11:
> >>>>> - support multiple onboard hubs connected to the same parent
> >>>>> - don't include ‘onboard_hub.h’ from the onboard hub driver
> >>>>>
> >>>>> Changes in v10:
> >>>>> - always use of_is_onboard_usb_hub() stub unless ONBOARD_USB_HUB=y/m
> >>>>> - keep 'regulator-boot-on' property for pp3300_hub
> >>>>>
> >>>>> Changes in v9:
> >>>>> - added dependency on ONBOARD_USB_HUB (or !!ONBOARD_USB_HUB) to
> >>>>>   USB_PLATFORM_XHCI
> >>>>>
> >>>>> Changes in v7:
> >>>>> - updated DT binding
> >>>>> - series rebased on qcom/arm64-for-5.13
> >>>>>
> >>>>> Changes in v6:
> >>>>> - updated summary
> >>>>>
> >>>>> Changes in v5:
> >>>>> - cover letter added
> >>>>>
> >>>>> Matthias Kaehlcke (6):
> >>>>>   usb: misc: Add onboard_usb_hub driver
> >>>>>   of/platform: Add stubs for of_platform_device_create/destroy()
> >>>>>   arm64: defconfig: Explicitly enable USB_XHCI_PLATFORM
> >>>>>   usb: Specify dependencies on USB_XHCI_PLATFORM with 'depends on'
> >>>>>   usb: host: xhci-plat: Create platform device for onboard hubs in
> >>>>>     probe()
> >>>>>   arm64: dts: qcom: sc7180-trogdor: Add nodes for onboard USB hub
> >>>>>
> >>>>>  .../sysfs-bus-platform-onboard-usb-hub        |   8 +
> >>>>>  MAINTAINERS                                   |   7 +
> >>>>>  .../boot/dts/qcom/sc7180-trogdor-lazor-r0.dts |  19 +-
> >>>>>  .../boot/dts/qcom/sc7180-trogdor-lazor-r1.dts |  12 +-
> >>>>>  .../arm64/boot/dts/qcom/sc7180-trogdor-r1.dts |  19 +-
> >>>>>  arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi  |  19 +-
> >>>>>  arch/arm64/configs/defconfig                  |   1 +
> >>>>>  drivers/usb/cdns3/Kconfig                     |   2 +-
> >>>>>  drivers/usb/dwc3/Kconfig                      |   5 +-
> >>>>>  drivers/usb/host/Kconfig                      |   5 +-
> >>>
> >>> These Kconfig changes are causing the resulting .config to be different.
> >>> For example, if I start with omap2plus_defconfig, the resulting .config
> >>> before and after your series is different as shown below
> >>>
> >>> :/work/linux$ diff /tmp/.config .config
> >>> 1902d1901
> >>> < # CONFIG_HISI_HIKEY_USB is not set
> >>> 4992c4991
> >>> < CONFIG_USB_XHCI_PLATFORM=m
> >>> ---
> >>>> # CONFIG_USB_XHCI_PLATFORM is not set
> >>> 5073,5075c5072
> >>> < # CONFIG_USB_DWC3_HOST is not set
> >>> < # CONFIG_USB_DWC3_GADGET is not set
> >>> < CONFIG_USB_DWC3_DUAL_ROLE=y
> >>> ---
> >>>> CONFIG_USB_DWC3_GADGET=y
> >>> 5173a5171
> >>>> # CONFIG_USB_ONBOARD_HUB is not set
> >>> 5285c5283
> >>> < CONFIG_USB_ROLE_SWITCH=m
> >>> ---
> >>>> # CONFIG_USB_ROLE_SWITCH is not set
> >>>
> >>> I would expect the same issues for multi_v7_defconfig and multi_v8_defconfig as well.
> >>
> >> Sorry I meant defconfig for arm64, not multi_v8_defconfig.
> >>
> >> I checked that for arm64 defconfig it is ok.
> >>
> >>> I'm ok to update the relevant defconfigs files so that the resulting .config is identical to
> >>> before your series. Thanks!
> >>
> >> With the below patch you can fix it for omap2plus_defconfig and multi_v7_defconfig.
> >>
> >> diff --git a/arch/arm/configs/multi_v7_defconfig b/arch/arm/configs/multi_v7_defconfig
> >> index d9abaae118dd..8c175ab37377 100644
> >> --- a/arch/arm/configs/multi_v7_defconfig
> >> +++ b/arch/arm/configs/multi_v7_defconfig
> >> @@ -787,6 +787,7 @@ CONFIG_SND_AUDIO_GRAPH_CARD=m
> >>  CONFIG_USB=y
> >>  CONFIG_USB_OTG=y
> >>  CONFIG_USB_XHCI_HCD=y
> >> +CONFIG_USB_XHCI_PLATFORM=y
> >>  CONFIG_USB_XHCI_MVEBU=y
> >>  CONFIG_USB_XHCI_TEGRA=m
> >>  CONFIG_USB_EHCI_HCD=y
> >> diff --git a/arch/arm/configs/omap2plus_defconfig b/arch/arm/configs/omap2plus_defconfig
> >> index 2ac2418084ab..a015fb04fa25 100644
> >> --- a/arch/arm/configs/omap2plus_defconfig
> >> +++ b/arch/arm/configs/omap2plus_defconfig
> >> @@ -562,6 +562,7 @@ CONFIG_USB=m
> >>  CONFIG_USB_ANNOUNCE_NEW_DEVICES=y
> >>  CONFIG_USB_MON=m
> >>  CONFIG_USB_XHCI_HCD=m
> >> +CONFIG_USB_XHCI_PLATFORM=m
> >>  CONFIG_USB_EHCI_HCD=m
> >>  CONFIG_USB_OHCI_HCD=m
> >>  CONFIG_USB_ACM=m
> > 
> > Thanks for testing!
> > 
> > I completely forgot that arm32 has all these different defconfigs.
> > 
> > While trying to adjust qcom_defconfig I came across something that confuses
> > me. The original defconfig results in:
> > 
> > # CONFIG_USB_XHCI_HCD is not set
> > CONFIG_USB_DWC3_DUAL_ROLE=y
> 
> The original Kconfig was:
> 
> > config USB_DWC3_DUAL_ROLE
> >         bool "Dual Role mode"
> >         depends on ((USB=y || USB=USB_DWC3) && (USB_GADGET=y || USB_GADGET=USB_DWC3))
> >         depends on (EXTCON=y || EXTCON=USB_DWC3)
> 
> Which means USB_DWC3_DUAL_ROLE can be enabled even without CONFIG_USB_XHCI_HCD.
> 
> All the dual role code does is add/remove the host/gadget controller platform devices.
> It doesn't care whether there is a driver for it or not.
> i.e. there is no build dependency on CONFIG_USB_XHCI_HCD.
> 
> > 
> > My assumption was that xHCI support is need for dwc3 dual mode (which is
> > made explicit by https://lore.kernel.org/patchwork/patch/1468240/), is
> > that incorrect? Maybe without xHCI support the controller can still
> > operate in USB 2.0 dual role mode?
> > 
> 
> Without xHCI support the host functionality will not work at all on dwc3 dual role.
> So I think your Kconfig changes for USB_DWC3_DUAL_ROLE to depend on USB_XHCI_PLATFORM
> are correct.

Thanks for the clarification!

Re: [PATCH v15 0/6] usb: misc: Add onboard_usb_hub driver

[Dmitry Baryshkov]

On Tue, 27 Jul 2021 at 03:41, Matthias Kaehlcke <mka@chromium.org> wrote:
>
> This series adds:
> - the onboard_usb_hub_driver
> - glue in the xhci-plat driver to create and destroy the
>   onboard_usb_hub platform devices if needed
> - a device tree binding for the Realtek RTS5411 USB hub controller
> - device tree changes that add RTS5411 entries for the QCA SC7180
>   based boards trogdor and lazor
> - a couple of stubs for platform device functions to avoid
>   unresolved symbols with certain kernel configs
>
> The main issue the driver addresses is that a USB hub needs to be
> powered before it can be discovered. For discrete onboard hubs (an
> example for such a hub is the Realtek RTS5411) this is often solved
> by supplying the hub with an 'always-on' regulator, which is kind
> of a hack. Some onboard hubs may require further initialization
> steps, like changing the state of a GPIO or enabling a clock, which
> requires even more hacks. This driver creates a platform device
> representing the hub which performs the necessary initialization.
> Currently it only supports switching on a single regulator, support
> for multiple regulators or other actions can be added as needed.
> Different initialization sequences can be supported based on the
> compatible string.

I have the feeling that you might want to check if you can use pwrseq
subsystem being proposed at
https://lore.kernel.org/linux-arm-msm/20211006035407.1147909-1-dmitry.baryshkov@linaro.org/.
It has been created for exactly the same reason of handling complex
power up/down requirements in a bus-neutral way. So instead of
creating an onboard-usb-hub, you might want to populate the hub node
with the reference to pwrseq device and make usb core call into
pwrseq. How does that sound to you?

>
> Besides performing the initialization the driver can be configured
> to power the hub off during system suspend. This can help to extend
> battery life on battery powered devices which have no requirements
> to keep the hub powered during suspend. The driver can also be
> configured to leave the hub powered when a wakeup capable USB device
> is connected when suspending, and power it off otherwise.


-- 
With best wishes
Dmitry

Re: [PATCH v15 0/6] usb: misc: Add onboard_usb_hub driver

[Matthias Kaehlcke]

Hi Dmitry,

On Tue, Oct 19, 2021 at 07:24:41PM +0300, Dmitry Baryshkov wrote:
> On Tue, 27 Jul 2021 at 03:41, Matthias Kaehlcke <mka@chromium.org> wrote:
> >
> > This series adds:
> > - the onboard_usb_hub_driver
> > - glue in the xhci-plat driver to create and destroy the
> >   onboard_usb_hub platform devices if needed
> > - a device tree binding for the Realtek RTS5411 USB hub controller
> > - device tree changes that add RTS5411 entries for the QCA SC7180
> >   based boards trogdor and lazor
> > - a couple of stubs for platform device functions to avoid
> >   unresolved symbols with certain kernel configs
> >
> > The main issue the driver addresses is that a USB hub needs to be
> > powered before it can be discovered. For discrete onboard hubs (an
> > example for such a hub is the Realtek RTS5411) this is often solved
> > by supplying the hub with an 'always-on' regulator, which is kind
> > of a hack. Some onboard hubs may require further initialization
> > steps, like changing the state of a GPIO or enabling a clock, which
> > requires even more hacks. This driver creates a platform device
> > representing the hub which performs the necessary initialization.
> > Currently it only supports switching on a single regulator, support
> > for multiple regulators or other actions can be added as needed.
> > Different initialization sequences can be supported based on the
> > compatible string.
> 
> I have the feeling that you might want to check if you can use pwrseq
> subsystem being proposed at
> https://lore.kernel.org/linux-arm-msm/20211006035407.1147909-1-dmitry.baryshkov@linaro.org/.
> It has been created for exactly the same reason of handling complex
> power up/down requirements in a bus-neutral way. So instead of
> creating an onboard-usb-hub, you might want to populate the hub node
> with the reference to pwrseq device and make usb core call into
> pwrseq. How does that sound to you?

Thanks for the pointer, it's good to see another attempt to sort out
power sequencing.

The pwrseq framework could potentially be used by the onboard_usb_hub
driver, but it probably can't replace it completely. Besides powering
the USB hub on before enumeration the driver also can optionally power
it off during system suspend when no wakeup capable USB devices are
connected, which can result in signifcant power savings on battery
powered devices. For this the driver needs knowledge about the USB
(hub) devices that are provided by a hub chip. That part is probably
best implemented by a driver under drivers/usb/.

It might be an option to have the USB core and the onboard_usb_hub
driver use the pwrseq framework, though we'd have to ensure that it
isn't a problem that the USB core turns power on (before
enumeration) and the onboard_usb_hub driver turns it off during
system suspend (and on again on resume).