1 /*- 2 * SPDX-License-Identifier: Beerware 3 * 4 * ---------------------------------------------------------------------------- 5 * "THE BEER-WARE LICENSE" (Revision 42): 6 * <phk@FreeBSD.org> wrote this file. As long as you retain this notice you 7 * can do whatever you want with this stuff. If we meet some day, and you think 8 * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp 9 * ---------------------------------------------------------------------------- 10 * 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 <sys/cdefs.h> 20 __FBSDID("$FreeBSD$"); 21 22 #include <sys/param.h> 23 #include <sys/lock.h> 24 #include <sys/kernel.h> 25 #include <sys/systm.h> 26 #include <sys/module.h> 27 #include <sys/sx.h> 28 #include <sys/bus.h> 29 #include <sys/conf.h> 30 #include <sys/timepps.h> 31 #include <machine/bus.h> 32 #include <machine/resource.h> 33 #include <sys/rman.h> 34 35 #include <dev/ppbus/ppbconf.h> 36 #include "ppbus_if.h" 37 #include <dev/ppbus/ppbio.h> 38 39 #define PPS_NAME "pps" /* our official name */ 40 41 #define PRVERBOSE(fmt, arg...) if (bootverbose) printf(fmt, ##arg); 42 43 struct pps_data { 44 struct ppb_device pps_dev; 45 struct pps_state pps[9]; 46 struct cdev *devs[9]; 47 device_t ppsdev; 48 device_t ppbus; 49 int busy; 50 struct callout timeout; 51 int lastdata; 52 53 struct sx lock; 54 struct resource *intr_resource; /* interrupt resource */ 55 void *intr_cookie; /* interrupt registration cookie */ 56 }; 57 58 static void ppsintr(void *arg); 59 static void ppshcpoll(void *arg); 60 61 #define DEVTOSOFTC(dev) \ 62 ((struct pps_data *)device_get_softc(dev)) 63 64 static devclass_t pps_devclass; 65 66 static d_open_t ppsopen; 67 static d_close_t ppsclose; 68 static d_ioctl_t ppsioctl; 69 70 static struct cdevsw pps_cdevsw = { 71 .d_version = D_VERSION, 72 .d_open = ppsopen, 73 .d_close = ppsclose, 74 .d_ioctl = ppsioctl, 75 .d_name = PPS_NAME, 76 }; 77 78 static void 79 ppsidentify(driver_t *driver, device_t parent) 80 { 81 82 device_t dev; 83 84 dev = device_find_child(parent, PPS_NAME, -1); 85 if (!dev) 86 BUS_ADD_CHILD(parent, 0, PPS_NAME, -1); 87 } 88 89 static int 90 ppstry(device_t ppbus, int send, int expect) 91 { 92 int i; 93 94 ppb_wdtr(ppbus, send); 95 i = ppb_rdtr(ppbus); 96 PRVERBOSE("S: %02x E: %02x G: %02x\n", send, expect, i); 97 return (i != expect); 98 } 99 100 static int 101 ppsprobe(device_t ppsdev) 102 { 103 device_set_desc(ppsdev, "Pulse per second Timing Interface"); 104 105 return (0); 106 } 107 108 static int 109 ppsattach(device_t dev) 110 { 111 struct pps_data *sc = DEVTOSOFTC(dev); 112 device_t ppbus = device_get_parent(dev); 113 struct cdev *d; 114 int error, i, unit, rid = 0; 115 116 /* declare our interrupt handler */ 117 sc->intr_resource = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, 118 RF_SHAREABLE); 119 120 /* interrupts seem mandatory */ 121 if (sc->intr_resource == NULL) { 122 device_printf(dev, "Unable to allocate interrupt resource\n"); 123 return (ENXIO); 124 } 125 126 error = bus_setup_intr(dev, sc->intr_resource, 127 INTR_TYPE_TTY | INTR_MPSAFE, NULL, ppsintr, 128 sc, &sc->intr_cookie); 129 if (error) { 130 bus_release_resource(dev, SYS_RES_IRQ, 0, sc->intr_resource); 131 device_printf(dev, "Unable to register interrupt handler\n"); 132 return (error); 133 } 134 135 sx_init(&sc->lock, "pps"); 136 ppb_init_callout(ppbus, &sc->timeout, 0); 137 sc->ppsdev = dev; 138 sc->ppbus = ppbus; 139 unit = device_get_unit(ppbus); 140 d = make_dev(&pps_cdevsw, unit, 141 UID_ROOT, GID_WHEEL, 0600, PPS_NAME "%d", unit); 142 sc->devs[0] = d; 143 sc->pps[0].ppscap = PPS_CAPTUREASSERT | PPS_ECHOASSERT; 144 d->si_drv1 = sc; 145 d->si_drv2 = (void*)0; 146 pps_init(&sc->pps[0]); 147 148 ppb_lock(ppbus); 149 if (ppb_request_bus(ppbus, dev, PPB_DONTWAIT)) { 150 ppb_unlock(ppbus); 151 return (0); 152 } 153 154 do { 155 i = ppb_set_mode(sc->ppbus, PPB_EPP); 156 PRVERBOSE("EPP: %d %d\n", i, PPB_IN_EPP_MODE(sc->ppbus)); 157 if (i == -1) 158 break; 159 i = 0; 160 ppb_wctr(ppbus, i); 161 if (ppstry(ppbus, 0x00, 0x00)) 162 break; 163 if (ppstry(ppbus, 0x55, 0x55)) 164 break; 165 if (ppstry(ppbus, 0xaa, 0xaa)) 166 break; 167 if (ppstry(ppbus, 0xff, 0xff)) 168 break; 169 170 i = IRQENABLE | PCD | STROBE | nINIT | SELECTIN; 171 ppb_wctr(ppbus, i); 172 PRVERBOSE("CTR = %02x (%02x)\n", ppb_rctr(ppbus), i); 173 if (ppstry(ppbus, 0x00, 0x00)) 174 break; 175 if (ppstry(ppbus, 0x55, 0x00)) 176 break; 177 if (ppstry(ppbus, 0xaa, 0x00)) 178 break; 179 if (ppstry(ppbus, 0xff, 0x00)) 180 break; 181 182 i = IRQENABLE | PCD | nINIT | SELECTIN; 183 ppb_wctr(ppbus, i); 184 PRVERBOSE("CTR = %02x (%02x)\n", ppb_rctr(ppbus), i); 185 ppstry(ppbus, 0x00, 0xff); 186 ppstry(ppbus, 0x55, 0xff); 187 ppstry(ppbus, 0xaa, 0xff); 188 ppstry(ppbus, 0xff, 0xff); 189 ppb_unlock(ppbus); 190 191 for (i = 1; i < 9; i++) { 192 d = make_dev(&pps_cdevsw, unit + 0x10000 * i, 193 UID_ROOT, GID_WHEEL, 0600, PPS_NAME "%db%d", unit, i - 1); 194 sc->devs[i] = d; 195 sc->pps[i].ppscap = PPS_CAPTUREASSERT | PPS_CAPTURECLEAR; 196 d->si_drv1 = sc; 197 d->si_drv2 = (void *)(intptr_t)i; 198 pps_init(&sc->pps[i]); 199 } 200 ppb_lock(ppbus); 201 } while (0); 202 i = ppb_set_mode(sc->ppbus, PPB_COMPATIBLE); 203 ppb_release_bus(ppbus, dev); 204 ppb_unlock(ppbus); 205 206 return (0); 207 } 208 209 static int 210 ppsopen(struct cdev *dev, int flags, int fmt, struct thread *td) 211 { 212 struct pps_data *sc = dev->si_drv1; 213 device_t ppbus = sc->ppbus; 214 int subdev = (intptr_t)dev->si_drv2; 215 int i; 216 217 /* 218 * The sx lock is here solely to serialize open()'s to close 219 * the race of concurrent open()'s when pps(4) doesn't own the 220 * ppbus. 221 */ 222 sx_xlock(&sc->lock); 223 ppb_lock(ppbus); 224 if (!sc->busy) { 225 device_t ppsdev = sc->ppsdev; 226 227 if (ppb_request_bus(ppbus, ppsdev, PPB_WAIT|PPB_INTR)) { 228 ppb_unlock(ppbus); 229 sx_xunlock(&sc->lock); 230 return (EINTR); 231 } 232 233 i = ppb_set_mode(sc->ppbus, PPB_PS2); 234 PRVERBOSE("EPP: %d %d\n", i, PPB_IN_EPP_MODE(sc->ppbus)); 235 236 i = IRQENABLE | PCD | nINIT | SELECTIN; 237 ppb_wctr(ppbus, i); 238 } 239 if (subdev > 0 && !(sc->busy & ~1)) { 240 /* XXX: Timeout of 1? hz/100 instead perhaps? */ 241 callout_reset(&sc->timeout, 1, ppshcpoll, sc); 242 sc->lastdata = ppb_rdtr(sc->ppbus); 243 } 244 sc->busy |= (1 << subdev); 245 ppb_unlock(ppbus); 246 sx_xunlock(&sc->lock); 247 return(0); 248 } 249 250 static int 251 ppsclose(struct cdev *dev, int flags, int fmt, struct thread *td) 252 { 253 struct pps_data *sc = dev->si_drv1; 254 int subdev = (intptr_t)dev->si_drv2; 255 256 sx_xlock(&sc->lock); 257 sc->pps[subdev].ppsparam.mode = 0; /* PHK ??? */ 258 ppb_lock(sc->ppbus); 259 sc->busy &= ~(1 << subdev); 260 if (subdev > 0 && !(sc->busy & ~1)) 261 callout_stop(&sc->timeout); 262 if (!sc->busy) { 263 device_t ppsdev = sc->ppsdev; 264 device_t ppbus = sc->ppbus; 265 266 ppb_wdtr(ppbus, 0); 267 ppb_wctr(ppbus, 0); 268 269 ppb_set_mode(ppbus, PPB_COMPATIBLE); 270 ppb_release_bus(ppbus, ppsdev); 271 } 272 ppb_unlock(sc->ppbus); 273 sx_xunlock(&sc->lock); 274 return(0); 275 } 276 277 static void 278 ppshcpoll(void *arg) 279 { 280 struct pps_data *sc = arg; 281 int i, j, k, l; 282 283 KASSERT(sc->busy & ~1, ("pps polling w/o opened devices")); 284 i = ppb_rdtr(sc->ppbus); 285 if (i == sc->lastdata) 286 return; 287 l = sc->lastdata ^ i; 288 k = 1; 289 for (j = 1; j < 9; j ++) { 290 if (l & k) { 291 pps_capture(&sc->pps[j]); 292 pps_event(&sc->pps[j], 293 i & k ? PPS_CAPTUREASSERT : PPS_CAPTURECLEAR); 294 } 295 k += k; 296 } 297 sc->lastdata = i; 298 callout_reset(&sc->timeout, 1, ppshcpoll, sc); 299 } 300 301 static void 302 ppsintr(void *arg) 303 { 304 struct pps_data *sc = (struct pps_data *)arg; 305 306 ppb_assert_locked(sc->ppbus); 307 pps_capture(&sc->pps[0]); 308 if (!(ppb_rstr(sc->ppbus) & nACK)) 309 return; 310 311 if (sc->pps[0].ppsparam.mode & PPS_ECHOASSERT) 312 ppb_wctr(sc->ppbus, IRQENABLE | AUTOFEED); 313 pps_event(&sc->pps[0], PPS_CAPTUREASSERT); 314 if (sc->pps[0].ppsparam.mode & PPS_ECHOASSERT) 315 ppb_wctr(sc->ppbus, IRQENABLE); 316 } 317 318 static int 319 ppsioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags, struct thread *td) 320 { 321 struct pps_data *sc = dev->si_drv1; 322 int subdev = (intptr_t)dev->si_drv2; 323 int err; 324 325 ppb_lock(sc->ppbus); 326 err = pps_ioctl(cmd, data, &sc->pps[subdev]); 327 ppb_unlock(sc->ppbus); 328 return (err); 329 } 330 331 static device_method_t pps_methods[] = { 332 /* device interface */ 333 DEVMETHOD(device_identify, ppsidentify), 334 DEVMETHOD(device_probe, ppsprobe), 335 DEVMETHOD(device_attach, ppsattach), 336 337 { 0, 0 } 338 }; 339 340 static driver_t pps_driver = { 341 PPS_NAME, 342 pps_methods, 343 sizeof(struct pps_data), 344 }; 345 DRIVER_MODULE(pps, ppbus, pps_driver, pps_devclass, 0, 0); 346 MODULE_DEPEND(pps, ppbus, 1, 1, 1); 347