xref: /dragonfly/sys/dev/misc/pps/pps.c (revision 2e3ed54d)
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: src/sys/dev/ppbus/pps.c,v 1.24.2.1 2000/05/24 00:20:57 n_hibma Exp $
10  * $DragonFly: src/sys/dev/misc/pps/pps.c,v 1.14 2005/10/28 03:25:50 dillon Exp $
11  *
12  * This driver implements a draft-mogul-pps-api-02.txt PPS source.
13  *
14  * The input pin is pin#10
15  * The echo output pin is pin#14
16  *
17  */
18 
19 #include "use_pps.h"
20 
21 #include <sys/param.h>
22 #include <sys/kernel.h>
23 #include <sys/systm.h>
24 #include <sys/module.h>
25 #include <sys/bus.h>
26 #include <sys/conf.h>
27 #include <sys/timepps.h>
28 #include <machine/bus.h>
29 #include <machine/resource.h>
30 #include <sys/rman.h>
31 
32 #include <bus/ppbus/ppbconf.h>
33 #include "ppbus_if.h"
34 #include <bus/ppbus/ppbio.h>
35 
36 #define PPS_NAME	"pps"		/* our official name */
37 
38 struct pps_data {
39 	int	pps_open;
40 	struct	ppb_device pps_dev;
41 	struct	pps_state pps;
42 
43 	struct resource *intr_resource;	/* interrupt resource */
44 	void *intr_cookie;		/* interrupt registration cookie */
45 };
46 
47 static void	ppsintr(void *arg);
48 
49 #define DEVTOSOFTC(dev) \
50 	((struct pps_data *)device_get_softc(dev))
51 #define UNITOSOFTC(unit) \
52 	((struct pps_data *)devclass_get_softc(pps_devclass, (unit)))
53 #define UNITODEVICE(unit) \
54 	(devclass_get_device(pps_devclass, (unit)))
55 
56 static devclass_t pps_devclass;
57 
58 static	d_open_t	ppsopen;
59 static	d_close_t	ppsclose;
60 static	d_ioctl_t	ppsioctl;
61 
62 #define CDEV_MAJOR 89
63 static struct cdevsw pps_cdevsw = {
64 	/* name */	PPS_NAME,
65 	/* maj */	CDEV_MAJOR,
66 	/* flags */	0,
67 	/* port */	NULL,
68 	/* clone */	NULL,
69 
70 	/* open */	ppsopen,
71 	/* close */	ppsclose,
72 	/* read */	noread,
73 	/* write */	nowrite,
74 	/* ioctl */	ppsioctl,
75 	/* poll */	nopoll,
76 	/* mmap */	nommap,
77 	/* strategy */	nostrategy,
78 	/* dump */	nodump,
79 	/* psize */	nopsize
80 };
81 
82 static int
83 ppsprobe(device_t ppsdev)
84 {
85 	struct pps_data *sc;
86 
87 	sc = DEVTOSOFTC(ppsdev);
88 	bzero(sc, sizeof(struct pps_data));
89 
90 	device_set_desc(ppsdev, "Pulse per second Timing Interface");
91 
92 	sc->pps.ppscap = PPS_CAPTUREASSERT | PPS_ECHOASSERT;
93 	pps_init(&sc->pps);
94 	return (0);
95 }
96 
97 static int
98 ppsattach(device_t ppsdev)
99 {
100 	struct pps_data *sc = DEVTOSOFTC(ppsdev);
101 	device_t ppbus = device_get_parent(ppsdev);
102 	int irq;
103 	int unit;
104 	int zero = 0;
105 
106 	/* retrieve the ppbus irq */
107 	BUS_READ_IVAR(ppbus, ppsdev, PPBUS_IVAR_IRQ, &irq);
108 
109 	if (irq > 0) {
110 		/* declare our interrupt handler */
111 		sc->intr_resource = bus_alloc_resource(ppsdev, SYS_RES_IRQ,
112 				       &zero, irq, irq, 1, RF_SHAREABLE);
113 	}
114 	/* interrupts seem mandatory */
115 	if (sc->intr_resource == 0)
116 		return (ENXIO);
117 
118 	unit = device_get_unit(ppsdev);
119 	cdevsw_add(&pps_cdevsw, -1, unit);
120 	make_dev(&pps_cdevsw, unit, UID_ROOT, GID_WHEEL, 0644,
121 		    PPS_NAME "%d", unit);
122 	return (0);
123 }
124 
125 static	int
126 ppsopen(dev_t dev, int flags, int fmt, struct thread *td)
127 {
128 	u_int unit = minor(dev);
129 	struct pps_data *sc = UNITOSOFTC(unit);
130 	device_t ppsdev = UNITODEVICE(unit);
131 	device_t ppbus = device_get_parent(ppsdev);
132 	int error;
133 
134 	if (!sc->pps_open) {
135 		if (ppb_request_bus(ppbus, ppsdev, PPB_WAIT|PPB_INTR))
136 			return (EINTR);
137 
138 		/* attach the interrupt handler */
139 		if ((error = BUS_SETUP_INTR(ppbus, ppsdev, sc->intr_resource,
140 			       0, ppsintr, ppsdev,
141 			       &sc->intr_cookie, NULL))) {
142 			ppb_release_bus(ppbus, ppsdev);
143 			return (error);
144 		}
145 
146 		ppb_wctr(ppbus, 0);
147 		ppb_wctr(ppbus, IRQENABLE);
148 		sc->pps_open = 1;
149 	}
150 
151 	return(0);
152 }
153 
154 static	int
155 ppsclose(dev_t dev, int flags, int fmt, struct thread *td)
156 {
157 	u_int unit = minor(dev);
158 	struct pps_data *sc = UNITOSOFTC(unit);
159 	device_t ppsdev = UNITODEVICE(unit);
160 	device_t ppbus = device_get_parent(ppsdev);
161 
162 	sc->pps.ppsparam.mode = 0;	/* PHK ??? */
163 
164 	ppb_wdtr(ppbus, 0);
165 	ppb_wctr(ppbus, 0);
166 
167 	/* Note: the interrupt handler is automatically detached */
168 	ppb_release_bus(ppbus, ppsdev);
169 	sc->pps_open = 0;
170 	return(0);
171 }
172 
173 static void
174 ppsintr(void *arg)
175 {
176 	device_t ppsdev = (device_t)arg;
177 	device_t ppbus = device_get_parent(ppsdev);
178 	struct pps_data *sc = DEVTOSOFTC(ppsdev);
179 	sysclock_t count;
180 
181 	count = sys_cputimer->count();
182 	if (!(ppb_rstr(ppbus) & nACK))
183 		return;
184 	if (sc->pps.ppsparam.mode & PPS_ECHOASSERT)
185 		ppb_wctr(ppbus, IRQENABLE | AUTOFEED);
186 	pps_event(&sc->pps, count, PPS_CAPTUREASSERT);
187 	if (sc->pps.ppsparam.mode & PPS_ECHOASSERT)
188 		ppb_wctr(ppbus, IRQENABLE);
189 }
190 
191 static int
192 ppsioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct thread *td)
193 {
194 	u_int unit = minor(dev);
195 	struct pps_data *sc = UNITOSOFTC(unit);
196 
197 	return (pps_ioctl(cmd, data, &sc->pps));
198 }
199 
200 /*
201  * Becuase pps is a static device under any attached ppbus, and not scanned
202  * by the ppbus, we need an identify function to create the device.
203  */
204 static device_method_t pps_methods[] = {
205 	/* device interface */
206 	DEVMETHOD(device_identify,	bus_generic_identify),
207 	DEVMETHOD(device_probe,		ppsprobe),
208 	DEVMETHOD(device_attach,	ppsattach),
209 
210 	{ 0, 0 }
211 };
212 
213 static driver_t pps_driver = {
214 	PPS_NAME,
215 	pps_methods,
216 	sizeof(struct pps_data),
217 };
218 DRIVER_MODULE(pps, ppbus, pps_driver, pps_devclass, 0, 0);
219