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

[Roger Quadros <rogerq@kernel.org>]

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