pps.c revision 183053
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 * 10 * This driver implements a draft-mogul-pps-api-02.txt PPS source. 11 * 12 * The input pin is pin#10 13 * The echo output pin is pin#14 14 * 15 */ 16 17#include <sys/cdefs.h> 18__FBSDID("$FreeBSD: head/sys/dev/ppbus/pps.c 183053 2008-09-15 22:26:32Z jhb $"); 19 20#include <sys/param.h> 21#include <sys/kernel.h> 22#include <sys/systm.h> 23#include <sys/module.h> 24#include <sys/bus.h> 25#include <sys/conf.h> 26#include <sys/timepps.h> 27#include <machine/bus.h> 28#include <machine/resource.h> 29#include <sys/rman.h> 30 31#include <dev/ppbus/ppbconf.h> 32#include "ppbus_if.h" 33#include <dev/ppbus/ppbio.h> 34 35#define PPS_NAME "pps" /* our official name */ 36 37#define PRVERBOSE(fmt, arg...) if (bootverbose) printf(fmt, ##arg); 38 39struct pps_data { 40 struct ppb_device pps_dev; 41 struct pps_state pps[9]; 42 struct cdev *devs[9]; 43 device_t ppsdev; 44 device_t ppbus; 45 int busy; 46 struct callout_handle timeout; 47 int lastdata; 48 49 struct mtx mtx; 50 struct resource *intr_resource; /* interrupt resource */ 51 void *intr_cookie; /* interrupt registration cookie */ 52}; 53 54static int ppsintr(void *arg); 55static void ppshcpoll(void *arg); 56 57#define DEVTOSOFTC(dev) \ 58 ((struct pps_data *)device_get_softc(dev)) 59 60static devclass_t pps_devclass; 61 62static d_open_t ppsopen; 63static d_close_t ppsclose; 64static d_ioctl_t ppsioctl; 65 66static struct cdevsw pps_cdevsw = { 67 .d_version = D_VERSION, 68 .d_open = ppsopen, 69 .d_close = ppsclose, 70 .d_ioctl = ppsioctl, 71 .d_name = PPS_NAME, 72}; 73 74static void 75ppsidentify(driver_t *driver, device_t parent) 76{ 77 78 device_t dev; 79 80 dev = device_find_child(parent, PPS_NAME, 0); 81 if (!dev) 82 BUS_ADD_CHILD(parent, 0, PPS_NAME, -1); 83} 84 85static int 86ppstry(device_t ppbus, int send, int expect) 87{ 88 int i; 89 90 ppb_wdtr(ppbus, send); 91 i = ppb_rdtr(ppbus); 92 PRVERBOSE("S: %02x E: %02x G: %02x\n", send, expect, i); 93 return (i != expect); 94} 95 96static int 97ppsprobe(device_t ppsdev) 98{ 99 device_set_desc(ppsdev, "Pulse per second Timing Interface"); 100 101 return (0); 102} 103 104static int 105ppsattach(device_t dev) 106{ 107 struct pps_data *sc = DEVTOSOFTC(dev); 108 device_t ppbus = device_get_parent(dev); 109 struct cdev *d; 110 int i, unit, rid = 0; 111 112 mtx_init(&sc->mtx, device_get_nameunit(dev), "pps", MTX_SPIN); 113 114 /* declare our interrupt handler */ 115 sc->intr_resource = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, 116 RF_SHAREABLE); 117 118 /* interrupts seem mandatory */ 119 if (sc->intr_resource == NULL) 120 return (ENXIO); 121 122 sc->ppsdev = dev; 123 sc->ppbus = ppbus; 124 unit = device_get_unit(ppbus); 125 d = make_dev(&pps_cdevsw, unit, 126 UID_ROOT, GID_WHEEL, 0600, PPS_NAME "%d", unit); 127 sc->devs[0] = d; 128 sc->pps[0].ppscap = PPS_CAPTUREASSERT | PPS_ECHOASSERT; 129 d->si_drv1 = sc; 130 d->si_drv2 = (void*)0; 131 pps_init(&sc->pps[0]); 132 133 if (ppb_request_bus(ppbus, dev, PPB_DONTWAIT)) 134 return (0); 135 136 do { 137 i = ppb_set_mode(sc->ppbus, PPB_EPP); 138 PRVERBOSE("EPP: %d %d\n", i, PPB_IN_EPP_MODE(sc->ppbus)); 139 if (i == -1) 140 break; 141 i = 0; 142 ppb_wctr(ppbus, i); 143 if (ppstry(ppbus, 0x00, 0x00)) 144 break; 145 if (ppstry(ppbus, 0x55, 0x55)) 146 break; 147 if (ppstry(ppbus, 0xaa, 0xaa)) 148 break; 149 if (ppstry(ppbus, 0xff, 0xff)) 150 break; 151 152 i = IRQENABLE | PCD | STROBE | nINIT | SELECTIN; 153 ppb_wctr(ppbus, i); 154 PRVERBOSE("CTR = %02x (%02x)\n", ppb_rctr(ppbus), i); 155 if (ppstry(ppbus, 0x00, 0x00)) 156 break; 157 if (ppstry(ppbus, 0x55, 0x00)) 158 break; 159 if (ppstry(ppbus, 0xaa, 0x00)) 160 break; 161 if (ppstry(ppbus, 0xff, 0x00)) 162 break; 163 164 i = IRQENABLE | PCD | nINIT | SELECTIN; 165 ppb_wctr(ppbus, i); 166 PRVERBOSE("CTR = %02x (%02x)\n", ppb_rctr(ppbus), i); 167 ppstry(ppbus, 0x00, 0xff); 168 ppstry(ppbus, 0x55, 0xff); 169 ppstry(ppbus, 0xaa, 0xff); 170 ppstry(ppbus, 0xff, 0xff); 171 172 for (i = 1; i < 9; i++) { 173 d = make_dev(&pps_cdevsw, unit + 0x10000 * i, 174 UID_ROOT, GID_WHEEL, 0600, PPS_NAME "%db%d", unit, i - 1); 175 sc->devs[i] = d; 176 sc->pps[i].ppscap = PPS_CAPTUREASSERT | PPS_CAPTURECLEAR; 177 d->si_drv1 = sc; 178 d->si_drv2 = (void *)(intptr_t)i; 179 pps_init(&sc->pps[i]); 180 } 181 } while (0); 182 i = ppb_set_mode(sc->ppbus, PPB_COMPATIBLE); 183 ppb_release_bus(ppbus, dev); 184 185 return (0); 186} 187 188static int 189ppsopen(struct cdev *dev, int flags, int fmt, struct thread *td) 190{ 191 struct pps_data *sc = dev->si_drv1; 192 int subdev = (intptr_t)dev->si_drv2; 193 int error, i; 194 195 if (!sc->busy) { 196 device_t ppsdev = sc->ppsdev; 197 device_t ppbus = sc->ppbus; 198 199 if (ppb_request_bus(ppbus, ppsdev, PPB_WAIT|PPB_INTR)) 200 return (EINTR); 201 202 /* attach the interrupt handler */ 203 if ((error = bus_setup_intr(ppsdev, sc->intr_resource, 204 (INTR_TYPE_TTY | INTR_MPSAFE), ppsintr, NULL, 205 sc, &sc->intr_cookie))) { 206 ppb_release_bus(ppbus, ppsdev); 207 return (error); 208 } 209 210 i = ppb_set_mode(sc->ppbus, PPB_PS2); 211 PRVERBOSE("EPP: %d %d\n", i, PPB_IN_EPP_MODE(sc->ppbus)); 212 213 i = IRQENABLE | PCD | nINIT | SELECTIN; 214 ppb_wctr(ppbus, i); 215 } 216 if (subdev > 0 && !(sc->busy & ~1)) { 217 sc->timeout = timeout(ppshcpoll, sc, 1); 218 sc->lastdata = ppb_rdtr(sc->ppbus); 219 } 220 sc->busy |= (1 << subdev); 221 return(0); 222} 223 224static int 225ppsclose(struct cdev *dev, int flags, int fmt, struct thread *td) 226{ 227 struct pps_data *sc = dev->si_drv1; 228 int subdev = (intptr_t)dev->si_drv2; 229 230 sc->pps[subdev].ppsparam.mode = 0; /* PHK ??? */ 231 sc->busy &= ~(1 << subdev); 232 if (subdev > 0 && !(sc->busy & ~1)) 233 untimeout(ppshcpoll, sc, sc->timeout); 234 if (!sc->busy) { 235 device_t ppsdev = sc->ppsdev; 236 device_t ppbus = sc->ppbus; 237 238 ppb_wdtr(ppbus, 0); 239 ppb_wctr(ppbus, 0); 240 241 /* Note: the interrupt handler is automatically detached */ 242 ppb_set_mode(ppbus, PPB_COMPATIBLE); 243 ppb_release_bus(ppbus, ppsdev); 244 } 245 return(0); 246} 247 248static void 249ppshcpoll(void *arg) 250{ 251 struct pps_data *sc = arg; 252 int i, j, k, l; 253 254 if (!(sc->busy & ~1)) 255 return; 256 mtx_lock_spin(&sc->mtx); 257 sc->timeout = timeout(ppshcpoll, sc, 1); 258 i = ppb_rdtr(sc->ppbus); 259 if (i == sc->lastdata) 260 return; 261 l = sc->lastdata ^ i; 262 k = 1; 263 for (j = 1; j < 9; j ++) { 264 if (l & k) { 265 pps_capture(&sc->pps[j]); 266 pps_event(&sc->pps[j], 267 i & k ? PPS_CAPTUREASSERT : PPS_CAPTURECLEAR); 268 } 269 k += k; 270 } 271 sc->lastdata = i; 272 mtx_unlock_spin(&sc->mtx); 273} 274 275static int 276ppsintr(void *arg) 277{ 278 struct pps_data *sc = (struct pps_data *)arg; 279 280 pps_capture(&sc->pps[0]); 281 if (!(ppb_rstr(sc->ppbus) & nACK)) 282 return (FILTER_STRAY); 283 if (sc->pps[0].ppsparam.mode & PPS_ECHOASSERT) 284 ppb_wctr(sc->ppbus, IRQENABLE | AUTOFEED); 285 mtx_lock_spin(&sc->mtx); 286 pps_event(&sc->pps[0], PPS_CAPTUREASSERT); 287 mtx_unlock_spin(&sc->mtx); 288 if (sc->pps[0].ppsparam.mode & PPS_ECHOASSERT) 289 ppb_wctr(sc->ppbus, IRQENABLE); 290 return (FILTER_HANDLED); 291} 292 293static int 294ppsioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags, struct thread *td) 295{ 296 struct pps_data *sc = dev->si_drv1; 297 int subdev = (intptr_t)dev->si_drv2; 298 int err; 299 300 mtx_lock_spin(&sc->mtx); 301 err = pps_ioctl(cmd, data, &sc->pps[subdev]); 302 mtx_unlock_spin(&sc->mtx); 303 return (err); 304} 305 306static device_method_t pps_methods[] = { 307 /* device interface */ 308 DEVMETHOD(device_identify, ppsidentify), 309 DEVMETHOD(device_probe, ppsprobe), 310 DEVMETHOD(device_attach, ppsattach), 311 312 { 0, 0 } 313}; 314 315static driver_t pps_driver = { 316 PPS_NAME, 317 pps_methods, 318 sizeof(struct pps_data), 319}; 320DRIVER_MODULE(pps, ppbus, pps_driver, pps_devclass, 0, 0); 321MODULE_DEPEND(pps, ppbus, 1, 1, 1); 322