u-boot/include/linux/iopoll.h
Jagan Teki c094e219a8 iopoll: Add dealy to read poll
Some drivers and other bsp code not only poll the
register with timeout but also required to delay
on each transaction.

This patch add that requirement by adding sleep_us
variable so-that read_poll_timeout now support
delay as well.

This change is referenced from Linux from below commit:
commit <5f5323a14cad19323060a8cbf9d96f2280a462dd> ("iopoll:
introduce read_poll_timeout macro")

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
2020-05-11 01:30:49 +05:30

73 lines
2.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (c) 2012-2014 The Linux Foundation. All rights reserved.
*/
#ifndef _LINUX_IOPOLL_H
#define _LINUX_IOPOLL_H
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/io.h>
#include <time.h>
/**
* read_poll_timeout - Periodically poll an address until a condition is met or a timeout occurs
* @op: accessor function (takes @addr as its only argument)
* @addr: Address to poll
* @val: Variable to read the value into
* @cond: Break condition (usually involving @val)
* @sleep_us: Maximum time to sleep in us
* @timeout_us: Timeout in us, 0 means never timeout
*
* Returns 0 on success and -ETIMEDOUT upon a timeout. In either
* case, the last read value at @addr is stored in @val.
*
* When available, you'll probably want to use one of the specialized
* macros defined below rather than this macro directly.
*/
#define read_poll_timeout(op, addr, val, cond, sleep_us, timeout_us) \
({ \
unsigned long timeout = timer_get_us() + timeout_us; \
for (;;) { \
(val) = op(addr); \
if (cond) \
break; \
if (timeout_us && time_after(timer_get_us(), timeout)) { \
(val) = op(addr); \
break; \
} \
if (sleep_us) \
udelay(sleep_us); \
} \
(cond) ? 0 : -ETIMEDOUT; \
})
#define readx_poll_timeout(op, addr, val, cond, timeout_us) \
read_poll_timeout(op, addr, val, cond, false, timeout_us)
#define readb_poll_timeout(addr, val, cond, timeout_us) \
readx_poll_timeout(readb, addr, val, cond, timeout_us)
#define readw_poll_timeout(addr, val, cond, timeout_us) \
readx_poll_timeout(readw, addr, val, cond, timeout_us)
#define readl_poll_timeout(addr, val, cond, timeout_us) \
readx_poll_timeout(readl, addr, val, cond, timeout_us)
#define readq_poll_timeout(addr, val, cond, timeout_us) \
readx_poll_timeout(readq, addr, val, cond, timeout_us)
#define readb_relaxed_poll_timeout(addr, val, cond, timeout_us) \
readx_poll_timeout(readb_relaxed, addr, val, cond, timeout_us)
#define readw_relaxed_poll_timeout(addr, val, cond, timeout_us) \
readx_poll_timeout(readw_relaxed, addr, val, cond, timeout_us)
#define readl_relaxed_poll_timeout(addr, val, cond, timeout_us) \
readx_poll_timeout(readl_relaxed, addr, val, cond, timeout_us)
#define readq_relaxed_poll_timeout(addr, val, cond, timeout_us) \
readx_poll_timeout(readq_relaxed, addr, val, cond, timeout_us)
#endif /* _LINUX_IOPOLL_H */