1 /*- 2 * Copyright (c) 1998 Nicolas Souchu, Marc Bouget 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $Id: lpbb.c,v 1.2 1998/11/09 22:22:01 nsouch Exp $ 27 * 28 */ 29 30 /* 31 * I2C Bit-Banging over parallel port 32 * 33 * See the Official Philips interface description in lpbb(4) 34 */ 35 36 #include <sys/param.h> 37 #include <sys/kernel.h> 38 #include <sys/systm.h> 39 #include <sys/module.h> 40 #include <sys/bus.h> 41 #include <sys/conf.h> 42 #include <sys/buf.h> 43 #include <sys/uio.h> 44 #include <sys/malloc.h> 45 46 #include <machine/clock.h> 47 48 #include <dev/ppbus/ppbconf.h> 49 50 #include <dev/iicbus/iiconf.h> 51 #include <dev/iicbus/iicbus.h> 52 53 #include "iicbb_if.h" 54 55 /* iicbus softc */ 56 struct lpbb_softc { 57 58 struct ppb_device lpbb_dev; 59 }; 60 61 static int lpbb_detect(struct lpbb_softc *); 62 63 static int lpbb_probe(device_t); 64 static int lpbb_attach(device_t); 65 static void lpbb_print_child(device_t, device_t); 66 67 static int lpbb_callback(device_t, int, caddr_t *); 68 static void lpbb_setlines(device_t, int, int); 69 static int lpbb_getdataline(device_t); 70 static int lpbb_reset(device_t, u_char, u_char, u_char *); 71 72 static devclass_t lpbb_devclass; 73 74 static device_method_t lpbb_methods[] = { 75 /* device interface */ 76 DEVMETHOD(device_probe, lpbb_probe), 77 DEVMETHOD(device_attach, lpbb_attach), 78 79 /* bus interface */ 80 DEVMETHOD(bus_print_child, lpbb_print_child), 81 82 /* iicbb interface */ 83 DEVMETHOD(iicbb_callback, lpbb_callback), 84 DEVMETHOD(iicbb_setlines, lpbb_setlines), 85 DEVMETHOD(iicbb_getdataline, lpbb_getdataline), 86 DEVMETHOD(iicbb_reset, lpbb_reset), 87 88 { 0, 0 } 89 }; 90 91 static driver_t lpbb_driver = { 92 "lpbb", 93 lpbb_methods, 94 DRIVER_TYPE_MISC, 95 sizeof(struct lpbb_softc), 96 }; 97 98 /* 99 * Make ourselves visible as a ppbus driver 100 */ 101 static struct ppb_device *lpbb_ppb_probe(struct ppb_data *ppb); 102 static int lpbb_ppb_attach(struct ppb_device *dev); 103 104 #define MAXLPBB 8 /* XXX not much better! */ 105 static struct lpbb_softc *lpbbdata[MAXLPBB]; 106 static int nlpbb = 0; 107 108 #ifdef KERNEL 109 110 static struct ppb_driver lpbbdriver = { 111 lpbb_ppb_probe, lpbb_ppb_attach, "lpbb" 112 }; 113 DATA_SET(ppbdriver_set, lpbbdriver); 114 115 #endif /* KERNEL */ 116 117 static int 118 lpbb_probe(device_t dev) 119 { 120 struct lpbb_softc *sc = lpbbdata[device_get_unit(dev)]; 121 struct lpbb_softc *scdst = (struct lpbb_softc *)device_get_softc(dev); 122 123 /* XXX copy softc. Yet, ppbus device is sc->lpbb_dev, but will be 124 * dev->parent when ppbus will be ported to the new bus architecture */ 125 bcopy(sc, scdst, sizeof(struct lpbb_softc)); 126 127 device_set_desc(dev, "parallel I2C bit-banging interface"); 128 129 /* probe done by ppbus initialization */ 130 return (0); 131 } 132 133 static int 134 lpbb_attach(device_t dev) 135 { 136 device_t bitbang, iicbus; 137 138 /* add generic bit-banging code */ 139 bitbang = device_add_child(dev, "iicbb", -1, NULL); 140 141 /* add the iicbus to the tree */ 142 iicbus = iicbus_alloc_bus(bitbang); 143 144 device_probe_and_attach(bitbang); 145 146 /* XXX should be in iicbb_attach! */ 147 device_probe_and_attach(iicbus); 148 149 return (0); 150 } 151 152 /* 153 * lppbb_ppb_probe() 154 */ 155 static struct ppb_device * 156 lpbb_ppb_probe(struct ppb_data *ppb) 157 { 158 struct lpbb_softc *sc; 159 160 sc = (struct lpbb_softc *) malloc(sizeof(struct lpbb_softc), 161 M_TEMP, M_NOWAIT); 162 if (!sc) { 163 printf("lpbb: cannot malloc!\n"); 164 return (0); 165 } 166 bzero(sc, sizeof(struct lpbb_softc)); 167 168 lpbbdata[nlpbb] = sc; 169 170 /* 171 * ppbus dependent initialisation. 172 */ 173 sc->lpbb_dev.id_unit = nlpbb; 174 sc->lpbb_dev.name = lpbbdriver.name; 175 sc->lpbb_dev.ppb = ppb; 176 sc->lpbb_dev.intr = 0; 177 178 if (!lpbb_detect(sc)) { 179 free(sc, M_TEMP); 180 return (NULL); 181 } 182 183 /* Ok, go to next device on next probe */ 184 nlpbb ++; 185 186 /* XXX wrong according to new bus architecture. ppbus needs to be 187 * ported 188 */ 189 return (&sc->lpbb_dev); 190 } 191 192 static int 193 lpbb_ppb_attach(struct ppb_device *dev) 194 { 195 /* add the parallel port I2C interface to the bus tree */ 196 if (!device_add_child(root_bus, "lpbb", dev->id_unit, NULL)) 197 return (0); 198 199 return (1); 200 } 201 202 static int 203 lpbb_callback(device_t dev, int index, caddr_t *data) 204 { 205 struct lpbb_softc *sc = (struct lpbb_softc *)device_get_softc(dev); 206 int error = 0; 207 int how; 208 209 switch (index) { 210 case IIC_REQUEST_BUS: 211 /* request the ppbus */ 212 how = *(int *)data; 213 error = ppb_request_bus(&sc->lpbb_dev, how); 214 break; 215 216 case IIC_RELEASE_BUS: 217 /* release the ppbus */ 218 error = ppb_release_bus(&sc->lpbb_dev); 219 break; 220 221 default: 222 error = EINVAL; 223 } 224 225 return (error); 226 } 227 228 #define SDA_out 0x80 229 #define SCL_out 0x08 230 #define SDA_in 0x80 231 #define SCL_in 0x08 232 #define ALIM 0x20 233 #define I2CKEY 0x50 234 235 static int getSDA(struct lpbb_softc *sc) 236 { 237 if((ppb_rstr(&sc->lpbb_dev)&SDA_in)==SDA_in) 238 return 1; 239 else 240 return 0; 241 } 242 243 static int getSCL(struct lpbb_softc *sc) 244 { 245 if((ppb_rstr(&sc->lpbb_dev)&SCL_in)==SCL_in) 246 return 1; 247 else 248 return 0; 249 } 250 251 static void setSDA(struct lpbb_softc *sc, char val) 252 { 253 if(val==0) 254 ppb_wdtr(&sc->lpbb_dev, (u_char)SDA_out); 255 else 256 ppb_wdtr(&sc->lpbb_dev, (u_char)~SDA_out); 257 } 258 259 static void setSCL(struct lpbb_softc *sc, unsigned char val) 260 { 261 if(val==0) 262 ppb_wctr(&sc->lpbb_dev, (u_char)(ppb_rctr(&sc->lpbb_dev)&~SCL_out)); 263 else 264 ppb_wctr(&sc->lpbb_dev, (u_char)(ppb_rctr(&sc->lpbb_dev)|SCL_out)); 265 } 266 267 static int lpbb_detect(struct lpbb_softc *sc) 268 { 269 if (ppb_request_bus(&sc->lpbb_dev, PPB_DONTWAIT)) { 270 printf("lpbb: can't allocate ppbus\n"); 271 return (0); 272 } 273 274 /* reset bus */ 275 setSDA(sc, 1); 276 setSCL(sc, 1); 277 278 if ((ppb_rstr(&sc->lpbb_dev) & I2CKEY) || 279 ((ppb_rstr(&sc->lpbb_dev) & ALIM) != ALIM)) { 280 281 ppb_release_bus(&sc->lpbb_dev); 282 return (0); 283 } 284 285 ppb_release_bus(&sc->lpbb_dev); 286 287 return (1); 288 } 289 290 static int 291 lpbb_reset(device_t dev, u_char speed, u_char addr, u_char * oldaddr) 292 { 293 struct lpbb_softc *sc = (struct lpbb_softc *)device_get_softc(dev); 294 295 /* reset bus */ 296 setSDA(sc, 1); 297 setSCL(sc, 1); 298 299 return (IIC_ENOADDR); 300 } 301 302 static void 303 lpbb_setlines(device_t dev, int ctrl, int data) 304 { 305 struct lpbb_softc *sc = (struct lpbb_softc *)device_get_softc(dev); 306 307 setSCL(sc, ctrl); 308 setSDA(sc, data); 309 } 310 311 static int 312 lpbb_getdataline(device_t dev) 313 { 314 struct lpbb_softc *sc = (struct lpbb_softc *)device_get_softc(dev); 315 316 return (getSDA(sc)); 317 } 318 319 static void 320 lpbb_print_child(device_t bus, device_t dev) 321 { 322 printf(" on %s%d", device_get_name(bus), device_get_unit(bus)); 323 324 return; 325 } 326 327 DRIVER_MODULE(lpbb, root, lpbb_driver, lpbb_devclass, 0, 0); 328