xref: /freebsd/sys/dev/ppbus/pps.c (revision 9207b4cff7b8d483f4dd3c62266c2b58819eb7f9)
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  * $FreeBSD$
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/module.h>
22 #include <sys/bus.h>
23 #include <sys/conf.h>
24 #include <sys/timetc.h>
25 #include <sys/timepps.h>
26 #include <machine/bus.h>
27 #include <machine/resource.h>
28 #include <sys/rman.h>
29 
30 #include <dev/ppbus/ppbconf.h>
31 #include "ppbus_if.h"
32 #include <dev/ppbus/ppbio.h>
33 
34 #define PPS_NAME	"pps"		/* our official name */
35 
36 struct pps_data {
37 	struct	ppb_device pps_dev;
38 	struct	pps_state pps[9];
39 	dev_t	devs[9];
40 	device_t ppsdev;
41 	device_t ppbus;
42 	int	busy;
43 	struct callout_handle timeout;
44 	int	lastdata;
45 
46 	struct resource *intr_resource;	/* interrupt resource */
47 	void *intr_cookie;		/* interrupt registration cookie */
48 };
49 
50 static void	ppsintr(void *arg);
51 static void 	ppshcpoll(void *arg);
52 
53 #define DEVTOSOFTC(dev) \
54 	((struct pps_data *)device_get_softc(dev))
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 	/* open */	ppsopen,
65 	/* close */	ppsclose,
66 	/* read */	noread,
67 	/* write */	nowrite,
68 	/* ioctl */	ppsioctl,
69 	/* poll */	nopoll,
70 	/* mmap */	nommap,
71 	/* strategy */	nostrategy,
72 	/* name */	PPS_NAME,
73 	/* maj */	CDEV_MAJOR,
74 	/* dump */	nodump,
75 	/* psize */	nopsize,
76 	/* flags */	0,
77 };
78 
79 static void
80 ppsidentify(driver_t *driver, device_t parent)
81 {
82 
83 	BUS_ADD_CHILD(parent, 0, PPS_NAME, 0);
84 }
85 
86 static int
87 ppstry(device_t ppbus, int send, int expect)
88 {
89 	int i;
90 
91 	ppb_wdtr(ppbus, send);
92 	i = ppb_rdtr(ppbus);
93 	printf("S: %02x E: %02x G: %02x\n", send, expect, i);
94 	return (i != expect);
95 }
96 
97 static int
98 ppsprobe(device_t ppsdev)
99 {
100 	struct pps_data *sc;
101 	dev_t dev;
102 	device_t ppbus;
103 	int unit, i;
104 
105 	device_set_desc(ppsdev, "Pulse per second Timing Interface");
106 
107 	sc = DEVTOSOFTC(ppsdev);
108 	bzero(sc, sizeof(struct pps_data));
109 	sc->ppsdev = ppsdev;
110 	ppbus = sc->ppbus = device_get_parent(ppsdev);
111 	unit = device_get_unit(ppbus);
112 	dev = make_dev(&pps_cdevsw, unit,
113 	    UID_ROOT, GID_WHEEL, 0644, PPS_NAME "%d", unit);
114 	sc->devs[0] = dev;
115 	sc->pps[0].ppscap = PPS_CAPTUREASSERT | PPS_ECHOASSERT;
116 	dev->si_drv1 = sc;
117 	dev->si_drv2 = (void*)0;
118 	pps_init(&sc->pps[0]);
119 
120 	if (ppb_request_bus(ppbus, ppsdev, PPB_DONTWAIT))
121 		return (0);
122 
123 
124 	do {
125 		i = ppb_set_mode(sc->ppbus, PPB_EPP);
126 		printf("EPP: %d %d\n", i, PPB_IN_EPP_MODE(sc->ppbus));
127 		if (i == -1)
128 			break;
129 		i = 0;
130 		ppb_wctr(ppbus, i);
131 		if (ppstry(ppbus, 0x00, 0x00))
132 			break;
133 		if (ppstry(ppbus, 0x55, 0x55))
134 			break;
135 		if (ppstry(ppbus, 0xaa, 0xaa))
136 			break;
137 		if (ppstry(ppbus, 0xff, 0xff))
138 			break;
139 
140 		i = IRQENABLE | PCD | STROBE | nINIT | SELECTIN;
141 		ppb_wctr(ppbus, i);
142 		printf("CTR = %02x (%02x)\n", ppb_rctr(ppbus), i);
143 		if (ppstry(ppbus, 0x00, 0x00))
144 			break;
145 		if (ppstry(ppbus, 0x55, 0x00))
146 			break;
147 		if (ppstry(ppbus, 0xaa, 0x00))
148 			break;
149 		if (ppstry(ppbus, 0xff, 0x00))
150 			break;
151 
152 		i = IRQENABLE | PCD | nINIT | SELECTIN;
153 		ppb_wctr(ppbus, i);
154 		printf("CTR = %02x (%02x)\n", ppb_rctr(ppbus), i);
155 		ppstry(ppbus, 0x00, 0xff);
156 		ppstry(ppbus, 0x55, 0xff);
157 		ppstry(ppbus, 0xaa, 0xff);
158 		ppstry(ppbus, 0xff, 0xff);
159 
160 		for (i = 1; i < 9; i++) {
161 			dev = make_dev(&pps_cdevsw, unit + 0x10000 * i,
162 			    UID_ROOT, GID_WHEEL, 0644, PPS_NAME "%db%d", unit, i - 1);
163 			sc->devs[i] = dev;
164 			sc->pps[i].ppscap = PPS_CAPTUREASSERT | PPS_CAPTURECLEAR;
165 			dev->si_drv1 = sc;
166 			dev->si_drv2 = (void*)i;
167 			pps_init(&sc->pps[i]);
168 		}
169 	} while (0);
170 	i = ppb_set_mode(sc->ppbus, PPB_COMPATIBLE);
171 	ppb_release_bus(ppbus, ppsdev);
172 	return (0);
173 }
174 
175 static int
176 ppsattach(device_t dev)
177 {
178 	struct pps_data *sc = DEVTOSOFTC(dev);
179 	device_t ppbus = sc->ppbus;
180 	int irq, zero = 0;
181 
182 	/* retrieve the ppbus irq */
183 	BUS_READ_IVAR(ppbus, dev, PPBUS_IVAR_IRQ, &irq);
184 
185 	if (irq > 0) {
186 		/* declare our interrupt handler */
187 		sc->intr_resource = bus_alloc_resource(dev, SYS_RES_IRQ,
188 				       &zero, irq, irq, 1, RF_SHAREABLE);
189 	}
190 	/* interrupts seem mandatory */
191 	if (sc->intr_resource == 0)
192 		return (ENXIO);
193 
194 	return (0);
195 }
196 
197 static	int
198 ppsopen(dev_t dev, int flags, int fmt, struct thread *td)
199 {
200 	struct pps_data *sc = dev->si_drv1;
201 	int subdev = (int)dev->si_drv2;
202 	int error, i;
203 
204 	if (!sc->busy) {
205 		device_t ppsdev = sc->ppsdev;
206 		device_t ppbus = sc->ppbus;
207 
208 		if (ppb_request_bus(ppbus, ppsdev, PPB_WAIT|PPB_INTR))
209 			return (EINTR);
210 
211 		/* attach the interrupt handler */
212 		if ((error = BUS_SETUP_INTR(ppbus, ppsdev, sc->intr_resource,
213 			       INTR_TYPE_TTY, ppsintr, ppsdev,
214 			       &sc->intr_cookie))) {
215 			ppb_release_bus(ppbus, ppsdev);
216 			return (error);
217 		}
218 
219 		i = ppb_set_mode(sc->ppbus, PPB_PS2);
220 		printf("EPP: %d %d\n", i, PPB_IN_EPP_MODE(sc->ppbus));
221 
222 		i = IRQENABLE | PCD | nINIT | SELECTIN;
223 		ppb_wctr(ppbus, i);
224 	}
225 	if (subdev > 0 && !(sc->busy & ~1)) {
226 		sc->timeout = timeout(ppshcpoll, sc, 1);
227 		sc->lastdata = ppb_rdtr(sc->ppbus);
228 	}
229 	sc->busy |= (1 << subdev);
230 	return(0);
231 }
232 
233 static	int
234 ppsclose(dev_t dev, int flags, int fmt, struct thread *td)
235 {
236 	struct pps_data *sc = dev->si_drv1;
237 	int subdev = (int)dev->si_drv2;
238 
239 	sc->pps[subdev].ppsparam.mode = 0;	/* PHK ??? */
240 	sc->busy &= ~(1 << subdev);
241 	if (subdev > 0 && !(sc->busy & ~1))
242 		untimeout(ppshcpoll, sc, sc->timeout);
243 	if (!sc->busy) {
244 		device_t ppsdev = sc->ppsdev;
245 		device_t ppbus = sc->ppbus;
246 
247 		ppb_wdtr(ppbus, 0);
248 		ppb_wctr(ppbus, 0);
249 
250 		/* Note: the interrupt handler is automatically detached */
251 		ppb_set_mode(ppbus, PPB_COMPATIBLE);
252 		ppb_release_bus(ppbus, ppsdev);
253 	}
254 	return(0);
255 }
256 
257 static void
258 ppshcpoll(void *arg)
259 {
260 	struct pps_data *sc = arg;
261 	int i, j, k, l;
262 	struct timecounter *tc;
263 	unsigned count;
264 
265 	if (!(sc->busy & ~1))
266 		return;
267 	sc->timeout = timeout(ppshcpoll, sc, 1);
268 	i = ppb_rdtr(sc->ppbus);
269 	if (i == sc->lastdata)
270 		return;
271 	tc = timecounter;
272 	count = timecounter->tc_get_timecount(tc);
273 	l = sc->lastdata ^ i;
274 	k = 1;
275 	for (j = 1; j < 9; j ++) {
276 		if (l & k)
277 			pps_event(&sc->pps[j], tc, count,
278 			    i & k ?
279 			    PPS_CAPTUREASSERT : PPS_CAPTURECLEAR
280 			);
281 		k += k;
282 	}
283 	sc->lastdata = i;
284 }
285 
286 static void
287 ppsintr(void *arg)
288 {
289 	device_t ppsdev = (device_t)arg;
290 	struct pps_data *sc = DEVTOSOFTC(ppsdev);
291 	device_t ppbus = sc->ppbus;
292 	struct timecounter *tc;
293 	unsigned count;
294 
295 	tc = timecounter;
296 	count = timecounter->tc_get_timecount(tc);
297 	if (!(ppb_rstr(ppbus) & nACK))
298 		return;
299 	if (sc->pps[0].ppsparam.mode & PPS_ECHOASSERT)
300 		ppb_wctr(ppbus, IRQENABLE | AUTOFEED);
301 	pps_event(&sc->pps[0], tc, count, PPS_CAPTUREASSERT);
302 	if (sc->pps[0].ppsparam.mode & PPS_ECHOASSERT)
303 		ppb_wctr(ppbus, IRQENABLE);
304 }
305 
306 static int
307 ppsioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct thread *td)
308 {
309 	struct pps_data *sc = dev->si_drv1;
310 	int subdev = (int)dev->si_drv2;
311 
312 	return (pps_ioctl(cmd, data, &sc->pps[subdev]));
313 }
314 
315 static device_method_t pps_methods[] = {
316 	/* device interface */
317 	DEVMETHOD(device_identify,	ppsidentify),
318 	DEVMETHOD(device_probe,		ppsprobe),
319 	DEVMETHOD(device_attach,	ppsattach),
320 
321 	{ 0, 0 }
322 };
323 
324 static driver_t pps_driver = {
325 	PPS_NAME,
326 	pps_methods,
327 	sizeof(struct pps_data),
328 };
329 DRIVER_MODULE(pps, ppbus, pps_driver, pps_devclass, 0, 0);
330