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 1.4 1999/01/10 12:04:54 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 sizeof(struct lpbb_softc), 95 }; 96 97 /* 98 * Make ourselves visible as a ppbus driver 99 */ 100 static struct ppb_device *lpbb_ppb_probe(struct ppb_data *ppb); 101 static int lpbb_ppb_attach(struct ppb_device *dev); 102 103 #define MAXLPBB 8 /* XXX not much better! */ 104 static struct lpbb_softc *lpbbdata[MAXLPBB]; 105 static int nlpbb = 0; 106 107 #ifdef KERNEL 108 109 static struct ppb_driver lpbbdriver = { 110 lpbb_ppb_probe, lpbb_ppb_attach, "lpbb" 111 }; 112 DATA_SET(ppbdriver_set, lpbbdriver); 113 114 #endif /* KERNEL */ 115 116 static int 117 lpbb_probe(device_t dev) 118 { 119 struct lpbb_softc *sc = lpbbdata[device_get_unit(dev)]; 120 struct lpbb_softc *scdst = (struct lpbb_softc *)device_get_softc(dev); 121 122 /* XXX copy softc. Yet, ppbus device is sc->lpbb_dev, but will be 123 * dev->parent when ppbus will be ported to the new bus architecture */ 124 bcopy(sc, scdst, sizeof(struct lpbb_softc)); 125 126 device_set_desc(dev, "parallel I2C bit-banging interface"); 127 128 /* probe done by ppbus initialization */ 129 return (0); 130 } 131 132 static int 133 lpbb_attach(device_t dev) 134 { 135 device_t bitbang, iicbus; 136 137 /* add generic bit-banging code */ 138 bitbang = device_add_child(dev, "iicbb", -1, NULL); 139 140 /* add the iicbus to the tree */ 141 iicbus = iicbus_alloc_bus(bitbang); 142 143 device_probe_and_attach(bitbang); 144 145 /* XXX should be in iicbb_attach! */ 146 device_probe_and_attach(iicbus); 147 148 return (0); 149 } 150 151 /* 152 * lppbb_ppb_probe() 153 */ 154 static struct ppb_device * 155 lpbb_ppb_probe(struct ppb_data *ppb) 156 { 157 struct lpbb_softc *sc; 158 159 sc = (struct lpbb_softc *) malloc(sizeof(struct lpbb_softc), 160 M_TEMP, M_NOWAIT); 161 if (!sc) { 162 printf("lpbb: cannot malloc!\n"); 163 return (0); 164 } 165 bzero(sc, sizeof(struct lpbb_softc)); 166 167 lpbbdata[nlpbb] = sc; 168 169 /* 170 * ppbus dependent initialisation. 171 */ 172 sc->lpbb_dev.id_unit = nlpbb; 173 sc->lpbb_dev.name = lpbbdriver.name; 174 sc->lpbb_dev.ppb = ppb; 175 sc->lpbb_dev.intr = 0; 176 177 if (!lpbb_detect(sc)) { 178 free(sc, M_TEMP); 179 return (NULL); 180 } 181 182 /* Ok, go to next device on next probe */ 183 nlpbb ++; 184 185 /* XXX wrong according to new bus architecture. ppbus needs to be 186 * ported 187 */ 188 return (&sc->lpbb_dev); 189 } 190 191 static int 192 lpbb_ppb_attach(struct ppb_device *dev) 193 { 194 /* add the parallel port I2C interface to the bus tree */ 195 if (!device_add_child(root_bus, "lpbb", dev->id_unit, NULL)) 196 return (0); 197 198 return (1); 199 } 200 201 static int 202 lpbb_callback(device_t dev, int index, caddr_t *data) 203 { 204 struct lpbb_softc *sc = (struct lpbb_softc *)device_get_softc(dev); 205 int error = 0; 206 int how; 207 208 switch (index) { 209 case IIC_REQUEST_BUS: 210 /* request the ppbus */ 211 how = *(int *)data; 212 error = ppb_request_bus(&sc->lpbb_dev, how); 213 break; 214 215 case IIC_RELEASE_BUS: 216 /* release the ppbus */ 217 error = ppb_release_bus(&sc->lpbb_dev); 218 break; 219 220 default: 221 error = EINVAL; 222 } 223 224 return (error); 225 } 226 227 #define SDA_out 0x80 228 #define SCL_out 0x08 229 #define SDA_in 0x80 230 #define SCL_in 0x08 231 #define ALIM 0x20 232 #define I2CKEY 0x50 233 234 static int getSDA(struct lpbb_softc *sc) 235 { 236 if((ppb_rstr(&sc->lpbb_dev)&SDA_in)==SDA_in) 237 return 1; 238 else 239 return 0; 240 } 241 242 static void setSDA(struct lpbb_softc *sc, char val) 243 { 244 if(val==0) 245 ppb_wdtr(&sc->lpbb_dev, (u_char)SDA_out); 246 else 247 ppb_wdtr(&sc->lpbb_dev, (u_char)~SDA_out); 248 } 249 250 static void setSCL(struct lpbb_softc *sc, unsigned char val) 251 { 252 if(val==0) 253 ppb_wctr(&sc->lpbb_dev, (u_char)(ppb_rctr(&sc->lpbb_dev)&~SCL_out)); 254 else 255 ppb_wctr(&sc->lpbb_dev, (u_char)(ppb_rctr(&sc->lpbb_dev)|SCL_out)); 256 } 257 258 static int lpbb_detect(struct lpbb_softc *sc) 259 { 260 if (ppb_request_bus(&sc->lpbb_dev, PPB_DONTWAIT)) { 261 printf("lpbb: can't allocate ppbus\n"); 262 return (0); 263 } 264 265 /* reset bus */ 266 setSDA(sc, 1); 267 setSCL(sc, 1); 268 269 if ((ppb_rstr(&sc->lpbb_dev) & I2CKEY) || 270 ((ppb_rstr(&sc->lpbb_dev) & ALIM) != ALIM)) { 271 272 ppb_release_bus(&sc->lpbb_dev); 273 return (0); 274 } 275 276 ppb_release_bus(&sc->lpbb_dev); 277 278 return (1); 279 } 280 281 static int 282 lpbb_reset(device_t dev, u_char speed, u_char addr, u_char * oldaddr) 283 { 284 struct lpbb_softc *sc = (struct lpbb_softc *)device_get_softc(dev); 285 286 /* reset bus */ 287 setSDA(sc, 1); 288 setSCL(sc, 1); 289 290 return (IIC_ENOADDR); 291 } 292 293 static void 294 lpbb_setlines(device_t dev, int ctrl, int data) 295 { 296 struct lpbb_softc *sc = (struct lpbb_softc *)device_get_softc(dev); 297 298 setSCL(sc, ctrl); 299 setSDA(sc, data); 300 } 301 302 static int 303 lpbb_getdataline(device_t dev) 304 { 305 struct lpbb_softc *sc = (struct lpbb_softc *)device_get_softc(dev); 306 307 return (getSDA(sc)); 308 } 309 310 static void 311 lpbb_print_child(device_t bus, device_t dev) 312 { 313 printf(" on %s%d", device_get_name(bus), device_get_unit(bus)); 314 315 return; 316 } 317 318 DRIVER_MODULE(lpbb, root, lpbb_driver, lpbb_devclass, 0, 0); 319