staging: rtl8192u: Replace mdelay with usleep_range in rtl8192_usb_disconnect

rtl8192_usb_disconnect() is never called in atomic context.

rtl8192_usb_disconnect() is only set as ".disconnect" in
struct usb_driver.

Despite never getting called from atomic context,
rtl8192_usb_disconnect() calls mdelay() to busily wait.
This is not necessary and can be replaced with usleep_range() to
avoid busy waiting.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/rtl8192u/r8192U_core.c b/drivers/staging/rtl8192u/r8192U_core.c
index d607c59..532a713 100644 (file)
--- a/drivers/staging/rtl8192u/r8192U_core.c
+++ b/drivers/staging/rtl8192u/r8192U_core.c
@@ -5035,7 +5035,7 @@ static void rtl8192_usb_disconnect(struct usb_interface *intf)
                kfree(priv->pFirmware);
                priv->pFirmware = NULL;
                rtl8192_usb_deleteendpoints(dev);
-               mdelay(10);
+               usleep_range(10000, 11000);
        }
        free_ieee80211(dev);
        RT_TRACE(COMP_DOWN, "wlan driver removed\n");