]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
USB:ehci:fix Kunpeng920 ehci hardware problem
authorLongfang Liu <liulongfang@huawei.com>
Fri, 9 Apr 2021 08:48:01 +0000 (16:48 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 10 Apr 2021 08:45:38 +0000 (10:45 +0200)
commit26b75952ca0b8b4b3050adb9582c8e2f44d49687
tree83be97fd37d111f0032443dab105fb45919e6fc8
parent496960274153bdeb9d1f904ff1ea875cef8232c1
USB:ehci:fix Kunpeng920 ehci hardware problem

Kunpeng920's EHCI controller does not have SBRN register.
Reading the SBRN register when the controller driver is
initialized will get 0.

When rebooting the EHCI driver, ehci_shutdown() will be called.
if the sbrn flag is 0, ehci_shutdown() will return directly.
The sbrn flag being 0 will cause the EHCI interrupt signal to
not be turned off after reboot. this interrupt that is not closed
will cause an exception to the device sharing the interrupt.

Therefore, the EHCI controller of Kunpeng920 needs to skip
the read operation of the SBRN register.

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Longfang Liu <liulongfang@huawei.com>
Link: https://lore.kernel.org/r/1617958081-17999-1-git-send-email-liulongfang@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/host/ehci-pci.c