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