When inserting a USB device, examining hcd->rsrc_start can be
helpful in identifying which hcd is mounted, as the physical
address represented here is typically unique.
The following code snippet demonstrates this:
struct usb_hcd *hcd = bus_to_hcd(udev->bus);
unsigned long long usb_hcd_addr = (unsigned long long)hcd->rsrc_start;
However, this approach has limitations now. For USB hosts with an
MMIO interface, the effectiveness of this method is restricted to
USB 2.0.
Because commit 3429e91a661e ("usb: host: xhci: add platform driver
support") assigned res->start to hcd->rsrc_start. But
shared_hcd->rsrc_start remains unassigned, which is also necessary
in certain scenarios.
Fixes: 3429e91a661e ("usb: host: xhci: add platform driver support")
Co-developed-by: Xu Rao <raoxu@xxxxxxxxxxxxx>
Signed-off-by: Xu Rao <raoxu@xxxxxxxxxxxxx>
Signed-off-by: WangYuli <wangyuli@xxxxxxxxxxxxx>
--
Changlog:
*v1 -> v2: Move code changes for commit e0fe986972f5 ("usb: host:
xhci-plat: prepare operation w/o shared hcd").
v2 -> v3: Add the "Fixes" tag and fix a typo in commit message.
---
drivers/usb/host/xhci-plat.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index e6c9006bd568..457e839b9b53 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -329,6 +329,8 @@ int xhci_plat_probe(struct platform_device *pdev, struct device *sysdev, const s
usb3_hcd->can_do_streams = 1;
if (xhci->shared_hcd) {
+ xhci->shared_hcd->rsrc_start = hcd->rsrc_start;
+ xhci->shared_hcd->rsrc_len = hcd->rsrc_len;
ret = usb_add_hcd(xhci->shared_hcd, irq, IRQF_SHARED);
if (ret)
goto put_usb3_hcd;
--
2.47.1
