pps.c revision 51658 
1/*
2 * ----------------------------------------------------------------------------
3 * "THE BEER-WARE LICENSE" (Revision 42):
4 * <phk@FreeBSD.org> wrote this file.  As long as you retain this notice you
5 * can do whatever you want with this stuff. If we meet some day, and you think
6 * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
7 * ----------------------------------------------------------------------------
8 *
9 * $FreeBSD: head/sys/dev/ppbus/pps.c 51658 1999-09-25 18:24:47Z phk $
10 *
11 * This driver implements a draft-mogul-pps-api-02.txt PPS source.
12 *
13 * The input pin is pin#10
14 * The echo output pin is pin#14
15 *
16 */
17
18#include <sys/param.h>
19#include <sys/kernel.h>
20#include <sys/systm.h>
21#include <sys/conf.h>
22#include <sys/timepps.h>
23#include <sys/malloc.h>
24
25#include <dev/ppbus/ppbconf.h>
26#include "pps.h"
27
28#define PPS_NAME	"pps"		/* our official name */
29
30struct pps_data {
31	int	pps_open;
32	struct	ppb_device pps_dev;
33	struct	pps_state pps;
34};
35
36static int npps;
37
38/*
39 * Make ourselves visible as a ppbus driver
40 */
41
42static struct ppb_device	*ppsprobe(struct ppb_data *ppb);
43static int			ppsattach(struct ppb_device *dev);
44static void			ppsintr(struct ppb_device *ppd);
45
46static struct ppb_driver ppsdriver = {
47    ppsprobe, ppsattach, PPS_NAME
48};
49
50DATA_SET(ppbdriver_set, ppsdriver);
51
52static	d_open_t	ppsopen;
53static	d_close_t	ppsclose;
54static	d_ioctl_t	ppsioctl;
55
56#define CDEV_MAJOR 89
57static struct cdevsw pps_cdevsw = {
58	/* open */	ppsopen,
59	/* close */	ppsclose,
60	/* read */	noread,
61	/* write */	nowrite,
62	/* ioctl */	ppsioctl,
63	/* poll */	nopoll,
64	/* mmap */	nommap,
65	/* strategy */	nostrategy,
66	/* name */	PPS_NAME,
67	/* maj */	CDEV_MAJOR,
68	/* dump */	nodump,
69	/* psize */	nopsize,
70	/* flags */	0,
71	/* bmaj */	-1
72};
73
74
75static struct ppb_device *
76ppsprobe(struct ppb_data *ppb)
77{
78	struct pps_data *sc;
79	static int once;
80	dev_t dev;
81
82	if (!once++)
83		cdevsw_add(&pps_cdevsw);
84
85	sc = (struct pps_data *) malloc(sizeof(struct pps_data),
86							M_TEMP, M_NOWAIT);
87	if (!sc) {
88		printf(PPS_NAME ": cannot malloc!\n");
89		return (0);
90	}
91	bzero(sc, sizeof(struct pps_data));
92
93	dev = make_dev(&pps_cdevsw, npps,
94	    UID_ROOT, GID_WHEEL, 0644, PPS_NAME "%d", npps);
95
96	dev->si_drv1 = sc;
97
98	sc->pps_dev.id_unit = npps++;
99	sc->pps_dev.ppb = ppb;
100	sc->pps_dev.name = ppsdriver.name;
101	sc->pps_dev.bintr = ppsintr;
102	sc->pps_dev.drv1 = sc;
103
104	sc->pps.ppscap = PPS_CAPTUREASSERT | PPS_ECHOASSERT;
105	pps_init(&sc->pps);
106	return (&sc->pps_dev);
107}
108
109static int
110ppsattach(struct ppb_device *dev)
111{
112
113	/*
114	 * Report ourselves
115	 */
116	printf(PPS_NAME "%d: <Pulse per second Timing Interface> on ppbus %d\n",
117	       dev->id_unit, dev->ppb->ppb_link->adapter_unit);
118
119	return (1);
120}
121
122static	int
123ppsopen(dev_t dev, int flags, int fmt, struct proc *p)
124{
125	struct pps_data *sc;
126	u_int unit = minor(dev);
127
128	if ((unit >= npps))
129		return (ENXIO);
130
131	sc = dev->si_drv1;
132
133	if (!sc->pps_open) {
134		if (ppb_request_bus(&sc->pps_dev, PPB_WAIT|PPB_INTR))
135			return (EINTR);
136
137		ppb_wctr(&sc->pps_dev, 0);
138		ppb_wctr(&sc->pps_dev, IRQENABLE);
139		sc->pps_open = 1;
140	}
141
142	return(0);
143}
144
145static	int
146ppsclose(dev_t dev, int flags, int fmt, struct proc *p)
147{
148	struct pps_data *sc = dev->si_drv1;
149
150	sc->pps.ppsparam.mode = 0;	/* PHK ??? */
151
152	ppb_wdtr(&sc->pps_dev, 0);
153	ppb_wctr(&sc->pps_dev, 0);
154
155	ppb_release_bus(&sc->pps_dev);
156	sc->pps_open = 0;
157	return(0);
158}
159
160static void
161ppsintr(struct ppb_device *ppd)
162{
163	struct pps_data *sc = ppd->drv1;
164	struct timecounter *tc;
165	unsigned count;
166
167	tc = timecounter;
168	count = timecounter->tc_get_timecount(tc);
169	if (!(ppb_rstr(&sc->pps_dev) & nACK))
170		return;
171	if (sc->pps.ppsparam.mode & PPS_ECHOASSERT)
172		ppb_wctr(&sc->pps_dev, IRQENABLE | AUTOFEED);
173	pps_event(&sc->pps, tc, count, PPS_CAPTUREASSERT);
174	if (sc->pps.ppsparam.mode & PPS_ECHOASSERT)
175		ppb_wctr(&sc->pps_dev, IRQENABLE);
176}
177
178static int
179ppsioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct proc *p)
180{
181	struct pps_data *sc = dev->si_drv1;
182
183	return (pps_ioctl(cmd, data, &sc->pps));
184}
185
186