hc
2023-12-11 d2ccde1c8e90d38cee87a1b0309ad2827f3fd30d
kernel/include/linux/iopoll.h
....@@ -1,15 +1,6 @@
1
+/* SPDX-License-Identifier: GPL-2.0-only */
12 /*
23 * 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
- *
134 */
145
156 #ifndef _LINUX_IOPOLL_H
....@@ -23,6 +14,92 @@
2314 #include <linux/io.h>
2415
2516 /**
17
+ * read_poll_timeout - Periodically poll an address until a condition is
18
+ * met or a timeout occurs
19
+ * @op: accessor function (takes @args as its arguments)
20
+ * @val: Variable to read the value into
21
+ * @cond: Break condition (usually involving @val)
22
+ * @sleep_us: Maximum time to sleep between reads in us (0
23
+ * tight-loops). Should be less than ~20ms since usleep_range
24
+ * is used (see Documentation/timers/timers-howto.rst).
25
+ * @timeout_us: Timeout in us, 0 means never timeout
26
+ * @sleep_before_read: if it is true, sleep @sleep_us before read.
27
+ * @args: arguments for @op poll
28
+ *
29
+ * Returns 0 on success and -ETIMEDOUT upon a timeout. In either
30
+ * case, the last read value at @args is stored in @val. Must not
31
+ * be called from atomic context if sleep_us or timeout_us are used.
32
+ *
33
+ * When available, you'll probably want to use one of the specialized
34
+ * macros defined below rather than this macro directly.
35
+ */
36
+#define read_poll_timeout(op, val, cond, sleep_us, timeout_us, \
37
+ sleep_before_read, args...) \
38
+({ \
39
+ u64 __timeout_us = (timeout_us); \
40
+ unsigned long __sleep_us = (sleep_us); \
41
+ ktime_t __timeout = ktime_add_us(ktime_get(), __timeout_us); \
42
+ might_sleep_if((__sleep_us) != 0); \
43
+ if (sleep_before_read && __sleep_us) \
44
+ usleep_range((__sleep_us >> 2) + 1, __sleep_us); \
45
+ for (;;) { \
46
+ (val) = op(args); \
47
+ if (cond) \
48
+ break; \
49
+ if (__timeout_us && \
50
+ ktime_compare(ktime_get(), __timeout) > 0) { \
51
+ (val) = op(args); \
52
+ break; \
53
+ } \
54
+ if (__sleep_us) \
55
+ usleep_range((__sleep_us >> 2) + 1, __sleep_us); \
56
+ } \
57
+ (cond) ? 0 : -ETIMEDOUT; \
58
+})
59
+
60
+/**
61
+ * read_poll_timeout_atomic - Periodically poll an address until a condition is
62
+ * met or a timeout occurs
63
+ * @op: accessor function (takes @args as its arguments)
64
+ * @val: Variable to read the value into
65
+ * @cond: Break condition (usually involving @val)
66
+ * @delay_us: Time to udelay between reads in us (0 tight-loops). Should
67
+ * be less than ~10us since udelay is used (see
68
+ * Documentation/timers/timers-howto.rst).
69
+ * @timeout_us: Timeout in us, 0 means never timeout
70
+ * @delay_before_read: if it is true, delay @delay_us before read.
71
+ * @args: arguments for @op poll
72
+ *
73
+ * Returns 0 on success and -ETIMEDOUT upon a timeout. In either
74
+ * case, the last read value at @args is stored in @val.
75
+ *
76
+ * When available, you'll probably want to use one of the specialized
77
+ * macros defined below rather than this macro directly.
78
+ */
79
+#define read_poll_timeout_atomic(op, val, cond, delay_us, timeout_us, \
80
+ delay_before_read, args...) \
81
+({ \
82
+ u64 __timeout_us = (timeout_us); \
83
+ unsigned long __delay_us = (delay_us); \
84
+ ktime_t __timeout = ktime_add_us(ktime_get(), __timeout_us); \
85
+ if (delay_before_read && __delay_us) \
86
+ udelay(__delay_us); \
87
+ for (;;) { \
88
+ (val) = op(args); \
89
+ if (cond) \
90
+ break; \
91
+ if (__timeout_us && \
92
+ ktime_compare(ktime_get(), __timeout) > 0) { \
93
+ (val) = op(args); \
94
+ break; \
95
+ } \
96
+ if (__delay_us) \
97
+ udelay(__delay_us); \
98
+ } \
99
+ (cond) ? 0 : -ETIMEDOUT; \
100
+})
101
+
102
+/**
26103 * readx_poll_timeout - Periodically poll an address until a condition is met or a timeout occurs
27104 * @op: accessor function (takes @addr as its only argument)
28105 * @addr: Address to poll
....@@ -30,7 +107,7 @@
30107 * @cond: Break condition (usually involving @val)
31108 * @sleep_us: Maximum time to sleep between reads in us (0
32109 * tight-loops). Should be less than ~20ms since usleep_range
33
- * is used (see Documentation/timers/timers-howto.txt).
110
+ * is used (see Documentation/timers/timers-howto.rst).
34111 * @timeout_us: Timeout in us, 0 means never timeout
35112 *
36113 * Returns 0 on success and -ETIMEDOUT upon a timeout. In either
....@@ -41,25 +118,7 @@
41118 * macros defined below rather than this macro directly.
42119 */
43120 #define readx_poll_timeout(op, addr, val, cond, sleep_us, timeout_us) \
44
-({ \
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); \
49
- for (;;) { \
50
- (val) = op(addr); \
51
- if (cond) \
52
- break; \
53
- if (__timeout_us && \
54
- ktime_compare(ktime_get(), __timeout) > 0) { \
55
- (val) = op(addr); \
56
- break; \
57
- } \
58
- if (__sleep_us) \
59
- usleep_range((__sleep_us >> 2) + 1, __sleep_us); \
60
- } \
61
- (cond) ? 0 : -ETIMEDOUT; \
62
-})
121
+ read_poll_timeout(op, val, cond, sleep_us, timeout_us, false, addr)
63122
64123 /**
65124 * readx_poll_timeout_atomic - Periodically poll an address until a condition is met or a timeout occurs
....@@ -69,7 +128,7 @@
69128 * @cond: Break condition (usually involving @val)
70129 * @delay_us: Time to udelay between reads in us (0 tight-loops). Should
71130 * be less than ~10us since udelay is used (see
72
- * Documentation/timers/timers-howto.txt).
131
+ * Documentation/timers/timers-howto.rst).
73132 * @timeout_us: Timeout in us, 0 means never timeout
74133 *
75134 * Returns 0 on success and -ETIMEDOUT upon a timeout. In either
....@@ -79,25 +138,7 @@
79138 * macros defined below rather than this macro directly.
80139 */
81140 #define readx_poll_timeout_atomic(op, addr, val, cond, delay_us, timeout_us) \
82
-({ \
83
- u64 __timeout_us = (timeout_us); \
84
- unsigned long __delay_us = (delay_us); \
85
- ktime_t __timeout = ktime_add_us(ktime_get(), __timeout_us); \
86
- for (;;) { \
87
- (val) = op(addr); \
88
- if (cond) \
89
- break; \
90
- if (__timeout_us && \
91
- ktime_compare(ktime_get(), __timeout) > 0) { \
92
- (val) = op(addr); \
93
- break; \
94
- } \
95
- if (__delay_us) \
96
- udelay(__delay_us); \
97
- } \
98
- (cond) ? 0 : -ETIMEDOUT; \
99
-})
100
-
141
+ read_poll_timeout_atomic(op, val, cond, delay_us, timeout_us, false, addr)
101142
102143 #define readb_poll_timeout(addr, val, cond, delay_us, timeout_us) \
103144 readx_poll_timeout(readb, addr, val, cond, delay_us, timeout_us)