RE: [PATCH 0/2] usb: cdns3: USBSSP platform driver support

[Pawel Laszczak]

>
>On 26-03-03 07:34:54, Pawel Laszczak wrote:
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>> >
>> >Hi Pawel,
>> >
>> >The Cadence USBSSP (CDNSP) controller was previously only accessible
>> >through PCI, coupling the gadget driver with the PCI glue layer into a single
>> >monolithic module (cdnsp-udc-pci). This prevented using the CDNSP IP on
>> >SoC/platform designs that expose the controller through device tree, eg, CIX
>> >Sky1 SoC.
>> >
>> >In this series, it restructures the driver to decouple the CDNSP gadget from
>> >PCI, and refactor cdnsp-pci.c into a thin PCI-to-platform wrapper (similar to
>> >cdns3-pci-wrap.c) that registers a platform device and passes PCI resources
>> >and platform data to the common platform driver. So, please help test it in
>> >your platform.
>> >
>> >The changes are tested with random configuration combination tests.
>> >
>> >============================================================
>> >ALL TESTS COMPLETE. Summary:
>> >============================================================
>> >Starting cdns3 config combination tests...
>> >Timestamp: 2026年 03月 02日 星期一 09:34:47 CST
>> >
>> >PASS: all-builtin (SUPPORT=y CDNS3=y GADGET=y HOST=y CDNSP=y
>> >CDNSP_G=y CDNSP_H=y)
>> >PASS: support-y_cdns3-m_gadget-y (SUPPORT=y CDNS3=m GADGET=y
>> >HOST=y CDNSP=y CDNSP_G=y CDNSP_H=y)
>> >PASS: support-y_cdns3-m_gadget-n (SUPPORT=y CDNS3=m GADGET=n
>> >HOST=y CDNSP=y CDNSP_G=y CDNSP_H=y)
>> >PASS: support-y_cdnsp-m_gadget-y (SUPPORT=y CDNS3=y GADGET=y HOST=y
>> >CDNSP=m CDNSP_G=y CDNSP_H=y)
>> >PASS: all-module (SUPPORT=m CDNS3=m GADGET=y HOST=y CDNSP=m
>> >CDNSP_G=y CDNSP_H=y)
>> >PASS: no-cdns3 (SUPPORT=y CDNS3=n GADGET=n HOST=n CDNSP=y
>> >CDNSP_G=y CDNSP_H=y)
>> >PASS: no-gadget (SUPPORT=y CDNS3=y GADGET=n HOST=y CDNSP=y
>> >CDNSP_G=n CDNSP_H=y)
>> >PASS: support-y_both-m_gadget-y (SUPPORT=y CDNS3=m GADGET=y HOST=y
>> >CDNSP=m CDNSP_G=y CDNSP_H=y)
>> >PASS: minimal-module (SUPPORT=m CDNS3=m GADGET=n HOST=n CDNSP=m
>> >CDNSP_G=n CDNSP_H=n)
>> >
>> >This patch was developed with assistance from Anthropic Claude Opus 4.6.
>> >
>>
>> I can compile the kernel but when I try to install modules with
>> make modules_install I get error:
>>
>> DEPMOD  /lib/modules/7.0.0-rc1-new-pci-plat-support-next-20260227+
>> depmod: ERROR: Cycle detected: cdns_usb_common -> cdnsp ->
>cdns_usb_common
>> depmod: ERROR: Cycle detected: udc_core
>> depmod: ERROR: Found 2 modules in dependency cycles!
>> make[2]: *** [scripts/Makefile.modinst:132: depmod] Error 1
>>
>> It occurs even with minimal configuration:
>> CONFIG_USB_CDNS_SUPPORT=m
>> # CONFIG_USB_CDNS3 is not set
>> CONFIG_USB_CDNSP=m
>> CONFIG_USB_CDNSP_GADGET=y
>>
>
>Thanks for testing. It needs to let cdns3(p) platform driver as
>standalone module to fix it. Would you please try below fix on top
>of my patch set:
>
>diff --git a/drivers/usb/cdns3/Makefile b/drivers/usb/cdns3/Makefile
>index 0e9b20e799d0..63484f145bb9 100644
>--- a/drivers/usb/cdns3/Makefile
>+++ b/drivers/usb/cdns3/Makefile
>@@ -3,12 +3,14 @@
> CFLAGS_cdns3-trace.o				:= -I$(src)
> CFLAGS_cdnsp-trace.o				:= -I$(src)
>
>-cdns-usb-common-y				:= core.o drd.o cdns3-plat.o
>+cdns-usb-common-y				:= core.o drd.o
>
> ifeq ($(CONFIG_USB),m)
> obj-m						+= cdns-usb-common.o
>+obj-m						+= cdns3-plat.o
> else
> obj-$(CONFIG_USB_CDNS_SUPPORT)			+= cdns-usb-common.o
>+obj-$(CONFIG_USB_CDNS_SUPPORT)			+= cdns3-plat.o
> endif
>
> cdns-usb-common-$(CONFIG_USB_CDNS_HOST) 	+= host.o
>

With this fix, the modules installation works correctly.

I have an additional comment regarding the grouping of USBSSP and CDNS3
options. Currently, they are not grouped together in menuconfig,
which looks a bit untidy. 
It might be better to move some of the Kconfig configuration higher up
to ensure they are properly grouped in the menu.

Regards
Pawel

>Besides, would you please comment [1], the key point is could we
>keep one platform driver with one compatible string, and cdns3 or cdnsp
>platform is decided at runtime?
>
>[1]
>https://urldefense.com/v3/__https://www.spinics.net/lists/kernel/msg6072480.
>html__;!!EHscmS1ygiU1lA!AMXCokQopzhe7zk6kKPFeLLp-
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>
>--
>
>Best regards,
>Peter