1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
|
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (c) 2012-2014 The Linux Foundation. All rights reserved.
*/
#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 */
|
