[PATCH 6.6 058/254] USB: OHCI/UHCI: Add soft dependencies on ehci_platform

Greg Kroah-Hartman
2026-01-28T15:29:37Z

From: Huacai Chen <chenhuacai@loongson.cn>

commit 01ef7f1b8713a78ab1a9512cf8096d2474c70633 upstream.

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 <stable@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>
Link: https://patch.msgid.link/20260112084802.1995923-1-chenhuacai@loongson.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/usb/host/ohci-platform.c | 1 +
drivers/usb/host/uhci-platform.c | 1 +
2 files changed, 2 insertions(+)

--- a/drivers/usb/host/ohci-platform.c
+++ b/drivers/usb/host/ohci-platform.c
@@ -376,3 +376,4 @@ MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_AUTHOR("Hauke Mehrtens");
MODULE_AUTHOR("Alan Stern");
MODULE_LICENSE("GPL");
+MODULE_SOFTDEP("pre: ehci_platform");
--- a/drivers/usb/host/uhci-platform.c
+++ b/drivers/usb/host/uhci-platform.c
@@ -191,3 +191,4 @@ static struct platform_driver uhci_platf
.of_match_table = platform_uhci_ids,
},
};
+MODULE_SOFTDEP("pre: ehci_platform");