1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 3 #ifndef _TIME_H 4 #define _TIME_H 5 6 #include <linux/typecheck.h> 7 8 unsigned long get_timer(unsigned long base); 9 10 /* 11 * Return the current value of a monotonically increasing microsecond timer. 12 * Granularity may be larger than 1us if hardware does not support this. 13 */ 14 unsigned long timer_get_us(void); 15 16 /* 17 * These inlines deal with timer wrapping correctly. You are 18 * strongly encouraged to use them 19 * 1. Because people otherwise forget 20 * 2. Because if the timer wrap changes in future you won't have to 21 * alter your driver code. 22 * 23 * time_after(a,b) returns true if the time a is after time b. 24 * 25 * Do this with "<0" and ">=0" to only test the sign of the result. A 26 * good compiler would generate better code (and a really good compiler 27 * wouldn't care). Gcc is currently neither. 28 */ 29 #define time_after(a,b) \ 30 (typecheck(unsigned long, a) && \ 31 typecheck(unsigned long, b) && \ 32 ((long)((b) - (a)) < 0)) 33 #define time_before(a,b) time_after(b,a) 34 35 #define time_after_eq(a,b) \ 36 (typecheck(unsigned long, a) && \ 37 typecheck(unsigned long, b) && \ 38 ((long)((a) - (b)) >= 0)) 39 #define time_before_eq(a,b) time_after_eq(b,a) 40 41 /* 42 * Calculate whether a is in the range of [b, c]. 43 */ 44 #define time_in_range(a,b,c) \ 45 (time_after_eq(a,b) && \ 46 time_before_eq(a,c)) 47 48 /* 49 * Calculate whether a is in the range of [b, c). 50 */ 51 #define time_in_range_open(a,b,c) \ 52 (time_after_eq(a,b) && \ 53 time_before(a,c)) 54 55 #endif /* _TIME_H */ 56
