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USB:ehci:fix Kunpeng920 ehci hardware problem

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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>
This commit is contained in:
Longfang Liu 2021-04-09 16:48:01 +08:00 committed by Greg Kroah-Hartman
parent 4969602741
commit 26b75952ca
1 changed files with 3 additions and 0 deletions
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3
drivers/usb/host/ehci-pci.c
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@ -297,6 +297,9 @@ static int ehci_pci_setup(struct usb_hcd *hcd)
if (pdev->vendor == PCI_VENDOR_ID_STMICRO
&& pdev->device == PCI_DEVICE_ID_STMICRO_USB_HOST)
; /* ConneXT has no sbrn register */
else if (pdev->vendor == PCI_VENDOR_ID_HUAWEI
&& pdev->device == 0xa239)
; /* HUAWEI Kunpeng920 USB EHCI has no sbrn register */
else
pci_read_config_byte(pdev, 0x60, &ehci->sbrn);