1 /* 2 * PPS API kernel header 3 * 4 * Copyright (C) 2009 Rodolfo Giometti <giometti@linux.it> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 19 */ 20 21 #ifndef LINUX_PPS_KERNEL_H 22 #define LINUX_PPS_KERNEL_H 23 24 #include <linux/pps.h> 25 #include <linux/cdev.h> 26 #include <linux/device.h> 27 #include <linux/time.h> 28 29 /* 30 * Global defines 31 */ 32 33 struct pps_device; 34 35 /* The specific PPS source info */ 36 struct pps_source_info { 37 char name[PPS_MAX_NAME_LEN]; /* symbolic name */ 38 char path[PPS_MAX_NAME_LEN]; /* path of connected device */ 39 int mode; /* PPS allowed mode */ 40 41 void (*echo)(struct pps_device *pps, 42 int event, void *data); /* PPS echo function */ 43 44 struct module *owner; 45 struct device *dev; /* Parent device for device_create */ 46 }; 47 48 struct pps_event_time { 49 #ifdef CONFIG_NTP_PPS 50 struct timespec64 ts_raw; 51 #endif /* CONFIG_NTP_PPS */ 52 struct timespec64 ts_real; 53 }; 54 55 /* The main struct */ 56 struct pps_device { 57 struct pps_source_info info; /* PSS source info */ 58 59 struct pps_kparams params; /* PPS current params */ 60 61 __u32 assert_sequence; /* PPS assert event seq # */ 62 __u32 clear_sequence; /* PPS clear event seq # */ 63 struct pps_ktime assert_tu; 64 struct pps_ktime clear_tu; 65 int current_mode; /* PPS mode at event time */ 66 67 unsigned int last_ev; /* last PPS event id */ 68 wait_queue_head_t queue; /* PPS event queue */ 69 70 unsigned int id; /* PPS source unique ID */ 71 void const *lookup_cookie; /* For pps_lookup_dev() only */ 72 struct cdev cdev; 73 struct device *dev; 74 struct fasync_struct *async_queue; /* fasync method */ 75 spinlock_t lock; 76 }; 77 78 /* 79 * Global variables 80 */ 81 82 extern const struct attribute_group *pps_groups[]; 83 84 /* 85 * Internal functions. 86 * 87 * These are not actually part of the exported API, but this is a 88 * convenient header file to put them in. 89 */ 90 91 extern int pps_register_cdev(struct pps_device *pps); 92 extern void pps_unregister_cdev(struct pps_device *pps); 93 94 /* 95 * Exported functions 96 */ 97 98 extern struct pps_device *pps_register_source( 99 struct pps_source_info *info, int default_params); 100 extern void pps_unregister_source(struct pps_device *pps); 101 extern void pps_event(struct pps_device *pps, 102 struct pps_event_time *ts, int event, void *data); 103 /* Look up a pps_device by magic cookie */ 104 struct pps_device *pps_lookup_dev(void const *cookie); 105 106 static inline void timespec_to_pps_ktime(struct pps_ktime *kt, 107 struct timespec64 ts) 108 { 109 kt->sec = ts.tv_sec; 110 kt->nsec = ts.tv_nsec; 111 } 112 113 static inline void pps_get_ts(struct pps_event_time *ts) 114 { 115 struct system_time_snapshot snap; 116 117 ktime_get_snapshot(&snap); 118 ts->ts_real = ktime_to_timespec64(snap.real); 119 #ifdef CONFIG_NTP_PPS 120 ts->ts_raw = ktime_to_timespec64(snap.raw); 121 #endif 122 } 123 124 /* Subtract known time delay from PPS event time(s) */ 125 static inline void pps_sub_ts(struct pps_event_time *ts, struct timespec64 delta) 126 { 127 ts->ts_real = timespec64_sub(ts->ts_real, delta); 128 #ifdef CONFIG_NTP_PPS 129 ts->ts_raw = timespec64_sub(ts->ts_raw, delta); 130 #endif 131 } 132 133 #endif /* LINUX_PPS_KERNEL_H */ 134