Re: [PATCH v2 0/9] arm64: dts: phy: st: usb: Add STM32MP2 USB support

[Fabrice Gasnier <fabrice.gasnier@foss.st.com>]

On 8/16/26 23:37, Marek Vasut wrote:
> Add USB support for STM32MP23xx/STM32MP25xx SoCs. This includes USB 2.0
> FEMTO-PHY driver, DWC3 glue code and DT adjustments. Parts of this are
> taken from ST downstream kernel fork, reduced, or rewritten, since not
> all of the content there was useful and bits which might be missing and
> are useful can be added later.
> 
> Unlike the downstream implementation, the DWC3 glue code is using plain
> dwc3-generic-plat, the EHCI and OHCI controllers are instantiated as
> plain generic controllers without any wrapper glue driver, and the USB2
> PHY driver is simplified.
> 
> Both USB 2.0 Host controller and DWC3 super-speed controller are tested.

Hi Marek,

Regarding dwc3, I've started to test and needed another patch from our
downstream. I've posted it here:
https://lore.kernel.org/linux-usb/20260817163101.6203-1-fabrice.gasnier@foss.st.com/


Regarding USBH, there's a dedicated glue on STM32MP2x SoCs for the
EHCI/OHCI controllers, similar to the dwc3. On dwc3, I see it can be
managed.

There are:
- AFMUX signals out of EHCI/OHCI controllers, to manage a Vbus power
switch (with polarity) control.
- AFMUX need pinctrl to be added, and managed during system PM
- On coming MP21 (not supported here), there's address translation control
- Common dedicated interrupt to manage wakeup

Using generic controller drivers, I don't see how to manage it, without
describing it in the DT.

For sure, generic ehci/ochi drivers and bindings can/must be used. What
would be the proper place for this glue to leave ? Why not adding the
glue driver from the downstream ? That's supposed to address this.

Do you wish I send it upstream, so it can be properly reviewed, amended ?

I'd like to sort this glue management out before the DT for the USBH can
land.

Best Regards,
Thanks,
Fabrice

> 
> Marek Vasut (6):
>   dt-bindings: usb: generic-ehci: Document access-controllers property
>   dt-bindings: usb: generic-ohci: Document access-controllers property
>   dt-bindings: usb: dwc3: Document ST STM32MP2 DWC3 xHCI USB controller
>   usb: dwc3: dwc3-generic-plat: Add ST STM32MP2 DWC3 xHCI USB controller
>     glue
>   dt-bindings: arm: stm32: Switch st,stm32mp23/25-syscfg into simple-mfd
>   arm64: dts: st: Add USB nodes on stm32mp231
> 
> Pankaj Dev (3):
>   dt-bindings: phy: Document ST STM32MP25 USB2-FEMTO PHY
>   phy: stm32: Add support for ST STM32MP25 USB2-FEMTO PHY
>   arm64: dts: st: Add USB nodes on stm32mp251
> 
>  .../bindings/arm/stm32/st,stm32-syscon.yaml   |   7 +-
>  .../bindings/phy/st,stm32-usb2phy.yaml        |  73 ++++
>  .../devicetree/bindings/usb/generic-ehci.yaml |   3 +
>  .../devicetree/bindings/usb/generic-ohci.yaml |   3 +
>  .../bindings/usb/st,stm32mp25-dwc3.yaml       | 108 ++++++
>  arch/arm64/boot/dts/st/stm32mp231.dtsi        |  81 +++-
>  arch/arm64/boot/dts/st/stm32mp251.dtsi        |  65 +++-
>  drivers/phy/st/Kconfig                        |  10 +
>  drivers/phy/st/Makefile                       |   1 +
>  drivers/phy/st/phy-stm32-usb2phy.c            | 361 ++++++++++++++++++
>  drivers/usb/dwc3/dwc3-generic-plat.c          |  44 +++
>  11 files changed, 751 insertions(+), 5 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/phy/st,stm32-usb2phy.yaml
>  create mode 100644 Documentation/devicetree/bindings/usb/st,stm32mp25-dwc3.yaml
>  create mode 100644 drivers/phy/st/phy-stm32-usb2phy.c
> 
> Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>
> Cc: Christian Bruel <christian.bruel@foss.st.com>
> Cc: Conor Dooley <conor+dt@kernel.org>
> Cc: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Krzysztof Kozlowski <krzk+dt@kernel.org>
> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
> Cc: Neil Armstrong <neil.armstrong@linaro.org>
> Cc: Pankaj Dev <pankaj.dev@st.com>
> Cc: Rahul Kumar <rahul.kumar05@st.com>
> Cc: Rob Herring <robh@kernel.org>
> Cc: Rosen Penev <rosenp@gmail.com>
> Cc: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
> Cc: Vinod Koul <vkoul@kernel.org>
> Cc: devicetree@vger.kernel.org
> Cc: kernel@dh-electronics.com
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-kernel@vger.kernel.org
> Cc: linux-phy@lists.infradead.org
> Cc: linux-stm32@st-md-mailman.stormreply.com
> Cc: linux-usb@vger.kernel.org
>