USB/host: Cleanup unneccessary irq disable code

Because the IRQF_DISABLED as the flag is now a NOOP and has been
deprecated and in hardirq context the interrupt is disabled.

so in usb/host code:
Removing the usage of flag IRQF_DISABLED;
Removing the calling local_irq save/restore actions in irq
handler usb_hcd_irq();
Signed-off-by: Nliu chuansheng <chuansheng.liu@intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/core/hcd.c

@@ -2153,15 +2153,8 @@ EXPORT_SYMBOL_GPL(usb_bus_start_enum);
 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
 {
 	struct usb_hcd		*hcd = __hcd;
-	unsigned long		flags;
 	irqreturn_t		rc;
 
-	/* IRQF_DISABLED doesn't work correctly with shared IRQs
-	 * when the first handler doesn't use it.  So let's just
-	 * assume it's never used.
-	 */
-	local_irq_save(flags);
-
 	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
 		rc = IRQ_NONE;
 	else if (hcd->driver->irq(hcd) == IRQ_NONE)
@@ -2169,7 +2162,6 @@ irqreturn_t usb_hcd_irq (int irq, void *__hcd)
 	else
 		rc = IRQ_HANDLED;
 
-	local_irq_restore(flags);
 	return rc;
 }
 EXPORT_SYMBOL_GPL(usb_hcd_irq);
@@ -2357,14 +2349,6 @@ static int usb_hcd_request_irqs(struct usb_hcd *hcd,
 	int retval;
 
 	if (hcd->driver->irq) {
-
-		/* IRQF_DISABLED doesn't work as advertised when used together
-		 * with IRQF_SHARED. As usb_hcd_irq() will always disable
-		 * interrupts we can remove it here.
-		 */
-		if (irqflags & IRQF_SHARED)
-			irqflags &= ~IRQF_DISABLED;
-
 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
 				hcd->driver->description, hcd->self.busnum);
 		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,

drivers/usb/host/ehci-ls1x.c

@@ -113,7 +113,7 @@ static int ehci_hcd_ls1x_probe(struct platform_device *pdev)
 		goto err_put_hcd;
 	}
 
-	ret = usb_add_hcd(hcd, irq, IRQF_DISABLED | IRQF_SHARED);
+	ret = usb_add_hcd(hcd, irq, IRQF_SHARED);
 	if (ret)
 		goto err_put_hcd;
 

drivers/usb/host/ohci-xls.c

@@ -56,7 +56,7 @@ static int ohci_xls_probe_internal(const struct hc_driver *driver,
 		goto err3;
 	}
 
-	retval = usb_add_hcd(hcd, irq, IRQF_DISABLED | IRQF_SHARED);
+	retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
 	if (retval != 0)
 		goto err4;
 	return retval;