[mirror_ubuntu-bionic-kernel.git] / include / linux / iopoll.h

/*
 * Copyright (c) 2012-2014 The Linux Foundation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 and
 * only version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */

#ifndef _LINUX_IOPOLL_H
#define _LINUX_IOPOLL_H

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/ktime.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/io.h>

/**
 * readx_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 between reads in us (0
 *            tight-loops).  Should be less than ~20ms since usleep_range
 *            is used (see Documentation/timers/timers-howto.txt).
 * @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. Must not
 * be called from atomic context if sleep_us or timeout_us are used.
 *
 * When available, you'll probably want to use one of the specialized
 * macros defined below rather than this macro directly.
 */
#define readx_poll_timeout(op, addr, val, cond, sleep_us, timeout_us)	\
({ \
	u64 __timeout_us = (timeout_us); \
	unsigned long __sleep_us = (sleep_us); \
	ktime_t __timeout = ktime_add_us(ktime_get(), __timeout_us); \
	might_sleep_if((__sleep_us) != 0); \
	for (;;) { \
		(val) = op(addr); \
		if (cond) \
			break; \
		if (__timeout_us && \
		    ktime_compare(ktime_get(), __timeout) > 0) { \
			(val) = op(addr); \
			break; \
		} \
		if (__sleep_us) \
			usleep_range((__sleep_us >> 2) + 1, __sleep_us); \
	} \
	(cond) ? 0 : -ETIMEDOUT; \
})

/**
 * readx_poll_timeout_atomic - 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)
 * @delay_us: Time to udelay between reads in us (0 tight-loops).  Should
 *            be less than ~10us since udelay is used (see
 *            Documentation/timers/timers-howto.txt).
 * @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 readx_poll_timeout_atomic(op, addr, val, cond, delay_us, timeout_us) \
({ \
	u64 __timeout_us = (timeout_us); \
	unsigned long __delay_us = (delay_us); \
	ktime_t __timeout = ktime_add_us(ktime_get(), __timeout_us); \
	for (;;) { \
		(val) = op(addr); \
		if (cond) \
			break; \
		if (__timeout_us && \
		    ktime_compare(ktime_get(), __timeout) > 0) { \
			(val) = op(addr); \
			break; \
		} \
		if (__delay_us) \
			udelay(__delay_us);	\
	} \
	(cond) ? 0 : -ETIMEDOUT; \
})


#define readb_poll_timeout(addr, val, cond, delay_us, timeout_us) \
	readx_poll_timeout(readb, addr, val, cond, delay_us, timeout_us)

#define readb_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
	readx_poll_timeout_atomic(readb, addr, val, cond, delay_us, timeout_us)

#define readw_poll_timeout(addr, val, cond, delay_us, timeout_us) \
	readx_poll_timeout(readw, addr, val, cond, delay_us, timeout_us)

#define readw_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
	readx_poll_timeout_atomic(readw, addr, val, cond, delay_us, timeout_us)

#define readl_poll_timeout(addr, val, cond, delay_us, timeout_us) \
	readx_poll_timeout(readl, addr, val, cond, delay_us, timeout_us)

#define readl_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
	readx_poll_timeout_atomic(readl, addr, val, cond, delay_us, timeout_us)

#define readq_poll_timeout(addr, val, cond, delay_us, timeout_us) \
	readx_poll_timeout(readq, addr, val, cond, delay_us, timeout_us)

#define readq_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
	readx_poll_timeout_atomic(readq, addr, val, cond, delay_us, timeout_us)

#define readb_relaxed_poll_timeout(addr, val, cond, delay_us, timeout_us) \
	readx_poll_timeout(readb_relaxed, addr, val, cond, delay_us, timeout_us)

#define readb_relaxed_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
	readx_poll_timeout_atomic(readb_relaxed, addr, val, cond, delay_us, timeout_us)

#define readw_relaxed_poll_timeout(addr, val, cond, delay_us, timeout_us) \
	readx_poll_timeout(readw_relaxed, addr, val, cond, delay_us, timeout_us)

#define readw_relaxed_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
	readx_poll_timeout_atomic(readw_relaxed, addr, val, cond, delay_us, timeout_us)

#define readl_relaxed_poll_timeout(addr, val, cond, delay_us, timeout_us) \
	readx_poll_timeout(readl_relaxed, addr, val, cond, delay_us, timeout_us)

#define readl_relaxed_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
	readx_poll_timeout_atomic(readl_relaxed, addr, val, cond, delay_us, timeout_us)

#define readq_relaxed_poll_timeout(addr, val, cond, delay_us, timeout_us) \
	readx_poll_timeout(readq_relaxed, addr, val, cond, delay_us, timeout_us)

#define readq_relaxed_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
	readx_poll_timeout_atomic(readq_relaxed, addr, val, cond, delay_us, timeout_us)

#endif /* _LINUX_IOPOLL_H */
Commit	Line	Data
54c52312 MW	1	/*
	2	* Copyright (c) 2012-2014 The Linux Foundation. All rights reserved.
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 and
	6	* only version 2 as published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope that it will be useful,
	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	11	* GNU General Public License for more details.
	12	*
	13	*/
	14
	15	#ifndef _LINUX_IOPOLL_H
	16	#define _LINUX_IOPOLL_H
	17
	18	#include <linux/kernel.h>
	19	#include <linux/types.h>
16f4e319	20	#include <linux/ktime.h>
54c52312 MW	21	#include <linux/delay.h>
	22	#include <linux/errno.h>
	23	#include <linux/io.h>
	24
	25	/**
	26	* readx_poll_timeout - Periodically poll an address until a condition is met or a timeout occurs
	27	* @op: accessor function (takes @addr as its only argument)
	28	* @addr: Address to poll
	29	* @val: Variable to read the value into
	30	* @cond: Break condition (usually involving @val)
	31	* @sleep_us: Maximum time to sleep between reads in us (0
	32	* tight-loops). Should be less than ~20ms since usleep_range
	33	* is used (see Documentation/timers/timers-howto.txt).
	34	* @timeout_us: Timeout in us, 0 means never timeout
	35	*
	36	* Returns 0 on success and -ETIMEDOUT upon a timeout. In either
	37	* case, the last read value at @addr is stored in @val. Must not
	38	* be called from atomic context if sleep_us or timeout_us are used.
	39	*
	40	* When available, you'll probably want to use one of the specialized
	41	* macros defined below rather than this macro directly.
	42	*/
	43	#define readx_poll_timeout(op, addr, val, cond, sleep_us, timeout_us) \
	44	({ \
d15809f3 AB	45	u64 __timeout_us = (timeout_us); \
	46	unsigned long __sleep_us = (sleep_us); \
	47	ktime_t __timeout = ktime_add_us(ktime_get(), __timeout_us); \
	48	might_sleep_if((__sleep_us) != 0); \
54c52312 MW	49	for (;;) { \
	50	(val) = op(addr); \
	51	if (cond) \
	52	break; \
d15809f3 AB	53	if (__timeout_us && \
d15809f3 AB	54	ktime_compare(ktime_get(), __timeout) > 0) { \
54c52312 MW	55	(val) = op(addr); \
	56	break; \
	57	} \
d15809f3 AB	58	if (__sleep_us) \
d15809f3 AB	59	usleep_range((__sleep_us >> 2) + 1, __sleep_us); \
54c52312 MW	60	} \
	61	(cond) ? 0 : -ETIMEDOUT; \
	62	})
	63
	64	/**
	65	* readx_poll_timeout_atomic - Periodically poll an address until a condition is met or a timeout occurs
	66	* @op: accessor function (takes @addr as its only argument)
	67	* @addr: Address to poll
	68	* @val: Variable to read the value into
	69	* @cond: Break condition (usually involving @val)
	70	* @delay_us: Time to udelay between reads in us (0 tight-loops). Should
	71	* be less than ~10us since udelay is used (see
	72	* Documentation/timers/timers-howto.txt).
	73	* @timeout_us: Timeout in us, 0 means never timeout
	74	*
	75	* Returns 0 on success and -ETIMEDOUT upon a timeout. In either
	76	* case, the last read value at @addr is stored in @val.
	77	*
	78	* When available, you'll probably want to use one of the specialized
	79	* macros defined below rather than this macro directly.
	80	*/
	81	#define readx_poll_timeout_atomic(op, addr, val, cond, delay_us, timeout_us) \
	82	({ \
d15809f3 AB	83	u64 __timeout_us = (timeout_us); \
	84	unsigned long __delay_us = (delay_us); \
	85	ktime_t __timeout = ktime_add_us(ktime_get(), __timeout_us); \
54c52312 MW	86	for (;;) { \
	87	(val) = op(addr); \
	88	if (cond) \
	89	break; \
d15809f3 AB	90	if (__timeout_us && \
d15809f3 AB	91	ktime_compare(ktime_get(), __timeout) > 0) { \
54c52312 MW	92	(val) = op(addr); \
	93	break; \
	94	} \
d15809f3 AB	95	if (__delay_us) \
d15809f3 AB	96	udelay(__delay_us); \
54c52312 MW	97	} \
	98	(cond) ? 0 : -ETIMEDOUT; \
	99	})
	100
	101
	102	#define readb_poll_timeout(addr, val, cond, delay_us, timeout_us) \
	103	readx_poll_timeout(readb, addr, val, cond, delay_us, timeout_us)
	104
	105	#define readb_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
	106	readx_poll_timeout_atomic(readb, addr, val, cond, delay_us, timeout_us)
	107
	108	#define readw_poll_timeout(addr, val, cond, delay_us, timeout_us) \
	109	readx_poll_timeout(readw, addr, val, cond, delay_us, timeout_us)
	110
	111	#define readw_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
	112	readx_poll_timeout_atomic(readw, addr, val, cond, delay_us, timeout_us)
	113
	114	#define readl_poll_timeout(addr, val, cond, delay_us, timeout_us) \
	115	readx_poll_timeout(readl, addr, val, cond, delay_us, timeout_us)
	116
	117	#define readl_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
	118	readx_poll_timeout_atomic(readl, addr, val, cond, delay_us, timeout_us)
	119
	120	#define readq_poll_timeout(addr, val, cond, delay_us, timeout_us) \
	121	readx_poll_timeout(readq, addr, val, cond, delay_us, timeout_us)
	122
	123	#define readq_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
	124	readx_poll_timeout_atomic(readq, addr, val, cond, delay_us, timeout_us)
	125
	126	#define readb_relaxed_poll_timeout(addr, val, cond, delay_us, timeout_us) \
	127	readx_poll_timeout(readb_relaxed, addr, val, cond, delay_us, timeout_us)
	128
	129	#define readb_relaxed_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
	130	readx_poll_timeout_atomic(readb_relaxed, addr, val, cond, delay_us, timeout_us)
	131
	132	#define readw_relaxed_poll_timeout(addr, val, cond, delay_us, timeout_us) \
	133	readx_poll_timeout(readw_relaxed, addr, val, cond, delay_us, timeout_us)
	134
	135	#define readw_relaxed_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
	136	readx_poll_timeout_atomic(readw_relaxed, addr, val, cond, delay_us, timeout_us)
	137
	138	#define readl_relaxed_poll_timeout(addr, val, cond, delay_us, timeout_us) \
	139	readx_poll_timeout(readl_relaxed, addr, val, cond, delay_us, timeout_us)
	140
	141	#define readl_relaxed_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
	142	readx_poll_timeout_atomic(readl_relaxed, addr, val, cond, delay_us, timeout_us)
	143
	144	#define readq_relaxed_poll_timeout(addr, val, cond, delay_us, timeout_us) \
	145	readx_poll_timeout(readq_relaxed, addr, val, cond, delay_us, timeout_us)
	146
	147	#define readq_relaxed_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
	148	readx_poll_timeout_atomic(readq_relaxed, addr, val, cond, delay_us, timeout_us)
	149
	150	#endif /* _LINUX_IOPOLL_H */