usb: xhci: make 'sbrn' a local variable

Variable 'sbrn' is used to store the Serial Bus Release Number, which is
then only used for a debug message. Thus, 'sbrn' can be a local variable
and assigned after the primary HCD check. The SBRN debug message is only
printed when a primary HCD is setup.

Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20240905143300.1959279-8-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Epicurius

drivers/usb/host/xhci-pci.c

@@ -525,10 +525,9 @@ static int xhci_pci_setup(struct usb_hcd *hcd)
 	struct xhci_hcd		*xhci;
 	struct pci_dev		*pdev = to_pci_dev(hcd->self.controller);
 	int			retval;
+	u8			sbrn;
 
 	xhci = hcd_to_xhci(hcd);
-	if (!xhci->sbrn)
-		pci_read_config_byte(pdev, XHCI_SBRN_OFFSET, &xhci->sbrn);
 
 	/* imod_interval is the interrupt moderation value in nanoseconds. */
 	xhci->imod_interval = 40000;
@@ -543,7 +542,8 @@ static int xhci_pci_setup(struct usb_hcd *hcd)
 	if (xhci->quirks & XHCI_PME_STUCK_QUIRK)
 		xhci_pme_acpi_rtd3_enable(pdev);
 
-	xhci_dbg(xhci, "Got SBRN %u\n", (unsigned int) xhci->sbrn);
+	pci_read_config_byte(pdev, XHCI_SBRN_OFFSET, &sbrn);
+	xhci_dbg(xhci, "Got SBRN %u\n", (unsigned int)sbrn);
 
 	/* Find any debug ports */
 	return xhci_pci_reinit(xhci, pdev);

drivers/usb/host/xhci.h

@@ -1498,7 +1498,6 @@ struct xhci_hcd {
 	spinlock_t	lock;
 
 	/* packed release number */
-	u8		sbrn;
 	u16		hci_version;
 	u16		max_interrupters;
 	/* imod_interval in ns (I * 250ns) */