On Mon, Jan 12, 2026 at 04:48:02PM +0800, Huacai Chen wrote:

Commit 9beeee6584b9aa4f ("USB: EHCI: log a warning if ehci-hcd is not loaded first") said that ehci-hcd should be loaded before ohci-hcd and uhci-hcd. However, commit 05c92da0c52494ca ("usb: ohci/uhci - add soft dependencies on ehci_pci") only makes ohci-pci/uhci-pci depend on ehci- pci, which is not enough and we may still see the warnings in boot log.

To eliminate the warnings we should make ohci-hcd/uhci-hcd depend on ehci-hcd. But Alan said that the warning introduced by 9beeee6584b9aa4f is bogus, we only need the soft dependencies in the PCI level rather than the HCD level.

However, there is really another neccessary soft dependencies between ohci-platform/uhci-platform and ehci-platform, which is added by this patch. The boot logs are below.

1. ohci-platform loaded before ehci-platform:

ohci-platform 1f058000.usb: Generic Platform OHCI controller ohci-platform 1f058000.usb: new USB bus registered, assigned bus number 1 ohci-platform 1f058000.usb: irq 28, io mem 0x1f058000 hub 1-0:1.0: USB hub found hub 1-0:1.0: 4 ports detected Warning! ehci_hcd should always be loaded before uhci_hcd and ohci_hcd, not after usb 1-4: new low-speed USB device number 2 using ohci-platform ehci-platform 1f050000.usb: EHCI Host Controller ehci-platform 1f050000.usb: new USB bus registered, assigned bus number 2 ehci-platform 1f050000.usb: irq 29, io mem 0x1f050000 ehci-platform 1f050000.usb: USB 2.0 started, EHCI 1.00 usb 1-4: device descriptor read/all, error -62 hub 2-0:1.0: USB hub found hub 2-0:1.0: 4 ports detected usb 1-4: new low-speed USB device number 3 using ohci-platform input: YSPRINGTECH USB OPTICAL MOUSE as /devices/platform/bus@10000000/1f058000.usb/usb1/1-4/1-4:1.0/0003:10C4:8105.0001/input/input0 hid-generic 0003:10C4:8105.0001: input,hidraw0: USB HID v1.11 Mouse [YSPRINGTECH USB OPTICAL MOUSE] on usb-1f058000.usb-4/input0

2. ehci-platform loaded before ohci-platform:

ehci-platform 1f050000.usb: EHCI Host Controller ehci-platform 1f050000.usb: new USB bus registered, assigned bus number 1 ehci-platform 1f050000.usb: irq 28, io mem 0x1f050000 ehci-platform 1f050000.usb: USB 2.0 started, EHCI 1.00 hub 1-0:1.0: USB hub found hub 1-0:1.0: 4 ports detected ohci-platform 1f058000.usb: Generic Platform OHCI controller ohci-platform 1f058000.usb: new USB bus registered, assigned bus number 2 ohci-platform 1f058000.usb: irq 29, io mem 0x1f058000 hub 2-0:1.0: USB hub found hub 2-0:1.0: 4 ports detected usb 2-4: new low-speed USB device number 2 using ohci-platform input: YSPRINGTECH USB OPTICAL MOUSE as /devices/platform/bus@10000000/1f058000.usb/usb2/2-4/2-4:1.0/0003:10C4:8105.0001/input/input0 hid-generic 0003:10C4:8105.0001: input,hidraw0: USB HID v1.11 Mouse [YSPRINGTECH USB OPTICAL MOUSE] on usb-1f058000.usb-4/input0

In the later case, there is no re-connection for USB-1.0/1.1 devices, which is expected.

Cc: stable@vger.kernel.org Reported-by: Shengwen Xiao atzlinux@sina.com Signed-off-by: Huacai Chen chenhuacai@loongson.cn

---

Reviewed-by: Alan Stern stern@rowland.harvard.edu

drivers/usb/host/ohci-platform.c | 1 + drivers/usb/host/uhci-platform.c | 1 + 2 files changed, 2 insertions(+)

diff --git a/drivers/usb/host/ohci-platform.c b/drivers/usb/host/ohci-platform.c index 2e4bb5cc2165..c801527d5bd2 100644 --- a/drivers/usb/host/ohci-platform.c +++ b/drivers/usb/host/ohci-platform.c @@ -392,3 +392,4 @@ MODULE_DESCRIPTION(DRIVER_DESC); MODULE_AUTHOR("Hauke Mehrtens"); MODULE_AUTHOR("Alan Stern"); MODULE_LICENSE("GPL"); +MODULE_SOFTDEP("pre: ehci_platform"); diff --git a/drivers/usb/host/uhci-platform.c b/drivers/usb/host/uhci-platform.c index 5e02f2ceafb6..f4419d4526c4 100644 --- a/drivers/usb/host/uhci-platform.c +++ b/drivers/usb/host/uhci-platform.c @@ -211,3 +211,4 @@ static struct platform_driver uhci_platform_driver = { .of_match_table = platform_uhci_ids, }, };

+MODULE_SOFTDEP("pre: ehci_platform");

2.47.3