[RFC PATCH] USB:XHCI:Modify XHCI driver for USB2.0 controller

From: Longfang Liu
Date: Fri Feb 26 2021 - 03:25:10 EST


Our current XHCI hardware controller has been customized to only
support USB 2.0 ports. When using the current xhci driver, an xhci
controller device and an ehci controller device will be created
automatically. We want the driver to create only one ehci controller.
After modifying the driver as follows, an error will occur.
Is there any other modification method?

Signed-off-by: Longfang Liu <liulongfang@xxxxxxxxxx>
---
drivers/usb/host/xhci-pci.c | 15 ++-------------
1 file changed, 2 insertions(+), 13 deletions(-)

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index ef513c2..7296aad 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -364,26 +364,15 @@ static int xhci_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
/* USB 2.0 roothub is stored in the PCI device now. */
hcd = dev_get_drvdata(&dev->dev);
xhci = hcd_to_xhci(hcd);
- xhci->shared_hcd = usb_create_shared_hcd(&xhci_pci_hc_driver, &dev->dev,
- pci_name(dev), hcd);
- if (!xhci->shared_hcd) {
- retval = -ENOMEM;
- goto dealloc_usb2_hcd;
- }
-
+ xhci->shared_hcd = NULL;
retval = xhci_ext_cap_init(xhci);
if (retval)
goto put_usb3_hcd;

- retval = usb_add_hcd(xhci->shared_hcd, dev->irq,
+ retval = usb_add_hcd(xhci->main_hcd, dev->irq,
IRQF_SHARED);
if (retval)
goto put_usb3_hcd;
- /* Roothub already marked as USB 3.0 speed */
-
- if (!(xhci->quirks & XHCI_BROKEN_STREAMS) &&
- HCC_MAX_PSA(xhci->hcc_params) >= 4)
- xhci->shared_hcd->can_do_streams = 1;

/* USB-2 and USB-3 roothubs initialized, allow runtime pm suspend */
pm_runtime_put_noidle(&dev->dev);
--
2.8.1