1 /* 2 * PTP 1588 clock support - private declarations for the core module. 3 * 4 * Copyright (C) 2010 OMICRON electronics GmbH 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 #ifndef _PTP_PRIVATE_H_ 21 #define _PTP_PRIVATE_H_ 22 23 #include <linux/cdev.h> 24 #include <linux/device.h> 25 #include <linux/mutex.h> 26 #include <linux/posix-clock.h> 27 #include <linux/ptp_clock.h> 28 #include <linux/ptp_clock_kernel.h> 29 #include <linux/time.h> 30 31 #define PTP_MAX_TIMESTAMPS 128 32 #define PTP_BUF_TIMESTAMPS 30 33 34 struct timestamp_event_queue { 35 struct ptp_extts_event buf[PTP_MAX_TIMESTAMPS]; 36 int head; 37 int tail; 38 spinlock_t lock; 39 }; 40 41 struct ptp_clock { 42 struct posix_clock clock; 43 struct device *dev; 44 struct ptp_clock_info *info; 45 dev_t devid; 46 int index; /* index into clocks.map */ 47 struct pps_device *pps_source; 48 long dialed_frequency; /* remembers the frequency adjustment */ 49 struct timestamp_event_queue tsevq; /* simple fifo for time stamps */ 50 struct mutex tsevq_mux; /* one process at a time reading the fifo */ 51 struct mutex pincfg_mux; /* protect concurrent info->pin_config access */ 52 wait_queue_head_t tsev_wq; 53 int defunct; /* tells readers to go away when clock is being removed */ 54 struct device_attribute *pin_dev_attr; 55 struct attribute **pin_attr; 56 struct attribute_group pin_attr_group; 57 }; 58 59 /* 60 * The function queue_cnt() is safe for readers to call without 61 * holding q->lock. Readers use this function to verify that the queue 62 * is nonempty before proceeding with a dequeue operation. The fact 63 * that a writer might concurrently increment the tail does not 64 * matter, since the queue remains nonempty nonetheless. 65 */ 66 static inline int queue_cnt(struct timestamp_event_queue *q) 67 { 68 int cnt = q->tail - q->head; 69 return cnt < 0 ? PTP_MAX_TIMESTAMPS + cnt : cnt; 70 } 71 72 /* 73 * see ptp_chardev.c 74 */ 75 76 /* caller must hold pincfg_mux */ 77 int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin, 78 enum ptp_pin_function func, unsigned int chan); 79 80 long ptp_ioctl(struct posix_clock *pc, 81 unsigned int cmd, unsigned long arg); 82 83 int ptp_open(struct posix_clock *pc, fmode_t fmode); 84 85 ssize_t ptp_read(struct posix_clock *pc, 86 uint flags, char __user *buf, size_t cnt); 87 88 uint ptp_poll(struct posix_clock *pc, 89 struct file *fp, poll_table *wait); 90 91 /* 92 * see ptp_sysfs.c 93 */ 94 95 extern const struct attribute_group *ptp_groups[]; 96 97 int ptp_cleanup_sysfs(struct ptp_clock *ptp); 98 99 int ptp_populate_sysfs(struct ptp_clock *ptp); 100 101 #endif 102