[PATCH] xhci: Convert xhci_handshake() to use readl_poll_timeout()

[Andrey Smirnov]

Xhci_handshake() implements the algorithm already captured by
readl_poll_timeout(). Convert the former to use the latter to avoid
repetition.

Signed-off-by: Andrey Smirnov <andrew.smir...@gmail.com>
Cc: Mathias Nyman <mathias.ny...@intel.com>
Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Cc: linux-...@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/usb/host/xhci.c | 22 ++++++++++------------
 1 file changed, 10 insertions(+), 12 deletions(-)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 005e65922608..1b5306001340 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -9,6 +9,7 @@
  */
 
 #include <linux/pci.h>
+#include <linux/iopoll.h>
 #include <linux/irq.h>
 #include <linux/log2.h>
 #include <linux/module.h>
@@ -52,7 +53,6 @@ static bool td_on_ring(struct xhci_td *td, struct xhci_ring 
*ring)
        return false;
 }
 
-/* TODO: copied from ehci-hcd.c - can this be refactored? */
 /*
  * xhci_handshake - spin reading hc until handshake completes or fails
  * @ptr: address of hc register to be read
@@ -69,18 +69,16 @@ static bool td_on_ring(struct xhci_td *td, struct xhci_ring 
*ring)
 int xhci_handshake(void __iomem *ptr, u32 mask, u32 done, int usec)
 {
        u32     result;
+       int     ret;
 
-       do {
-               result = readl(ptr);
-               if (result == ~(u32)0)          /* card removed */
-                       return -ENODEV;
-               result &= mask;
-               if (result == done)
-                       return 0;
-               udelay(1);
-               usec--;
-       } while (usec > 0);
-       return -ETIMEDOUT;
+       ret = readl_poll_timeout(ptr, result,
+                                (result & mask) == done ||
+                                result == U32_MAX,
+                                1, usec);
+       if (result == U32_MAX)          /* card removed */
+               return -ENODEV;
+
+       return ret;
 }
 
 /*
-- 
2.20.1