]> git.baikalelectronics.ru Git - kernel.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)
commit1fb3a9c55da053582093b5106b156a8c0734ffcb
tree83be97fd37d111f0032443dab105fb45919e6fc8
parent4d4b432438f80bd4bb5173053f323a0f7204596f
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