pinctrl: baytrail: Add missing spinlock usage in byt_gpio_irq_handler

According to VLI64 Intel Atom E3800 Specification Update (#329901)
concurrent read accesses may result in returning 0xffffffff and write
accesses may be dropped silently.
To workaround all accesses must be protected by locks.

Cc: stable@vger.kernel.org
Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

path: root/tools/arch/xtensa/include/asm/barrier.h

/*
 * Copied from the kernel sources to tools/:
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2001 - 2012 Tensilica Inc.
 */

#ifndef _TOOLS_LINUX_XTENSA_SYSTEM_H
#define _TOOLS_LINUX_XTENSA_SYSTEM_H

#define mb()  ({ __asm__ __volatile__("memw" : : : "memory"); })
#define rmb() barrier()
#define wmb() mb()

#endif /* _TOOLS_LINUX_XTENSA_SYSTEM_H */