iic.c revision 157482
1/*- 2 * Copyright (c) 1998, 2001 Nicolas Souchu 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 * $FreeBSD: head/sys/dev/iicbus/iic.c 157482 2006-04-04 17:08:40Z imp $ 27 * 28 */ 29#include <sys/param.h> 30#include <sys/kernel.h> 31#include <sys/systm.h> 32#include <sys/malloc.h> 33#include <sys/module.h> 34#include <sys/bus.h> 35#include <sys/conf.h> 36#include <sys/uio.h> 37#include <sys/fcntl.h> 38 39#include <dev/iicbus/iiconf.h> 40#include <dev/iicbus/iicbus.h> 41#include <dev/iicbus/iic.h> 42 43#include "iicbus_if.h" 44 45#define BUFSIZE 1024 46 47struct iic_softc { 48 49 u_char sc_addr; /* 7 bit address on iicbus */ 50 int sc_count; /* >0 if device opened */ 51 52 char sc_buffer[BUFSIZE]; /* output buffer */ 53 char sc_inbuf[BUFSIZE]; /* input buffer */ 54 55 struct cdev *sc_devnode; 56}; 57 58#define IIC_SOFTC(unit) \ 59 ((struct iic_softc *)devclass_get_softc(iic_devclass, (unit))) 60 61#define IIC_DEVICE(unit) \ 62 (devclass_get_device(iic_devclass, (unit))) 63 64static int iic_probe(device_t); 65static int iic_attach(device_t); 66static int iic_detach(device_t); 67static void iic_identify(driver_t *driver, device_t parent); 68 69static devclass_t iic_devclass; 70 71static device_method_t iic_methods[] = { 72 /* device interface */ 73 DEVMETHOD(device_identify, iic_identify), 74 DEVMETHOD(device_probe, iic_probe), 75 DEVMETHOD(device_attach, iic_attach), 76 DEVMETHOD(device_detach, iic_detach), 77 78 /* iicbus interface */ 79 DEVMETHOD(iicbus_intr, iicbus_generic_intr), 80 81 { 0, 0 } 82}; 83 84static driver_t iic_driver = { 85 "iic", 86 iic_methods, 87 sizeof(struct iic_softc), 88}; 89 90static d_open_t iicopen; 91static d_close_t iicclose; 92static d_write_t iicwrite; 93static d_read_t iicread; 94static d_ioctl_t iicioctl; 95 96static struct cdevsw iic_cdevsw = { 97 .d_version = D_VERSION, 98 .d_flags = D_NEEDGIANT, 99 .d_open = iicopen, 100 .d_close = iicclose, 101 .d_read = iicread, 102 .d_write = iicwrite, 103 .d_ioctl = iicioctl, 104 .d_name = "iic", 105}; 106 107static void 108iic_identify(driver_t *driver, device_t parent) 109{ 110 BUS_ADD_CHILD(parent, 0, "iic", -1); 111} 112 113static int 114iic_probe(device_t dev) 115{ 116 device_set_desc(dev, "I2C generic I/O"); 117 return (0); 118} 119 120static int 121iic_attach(device_t dev) 122{ 123 struct iic_softc *sc = (struct iic_softc *)device_get_softc(dev); 124 125 if (!sc) 126 return (ENOMEM); 127 128 bzero(sc, sizeof(struct iic_softc)); 129 130 sc->sc_devnode = make_dev(&iic_cdevsw, device_get_unit(dev), 131 UID_ROOT, GID_WHEEL, 132 0600, "iic%d", device_get_unit(dev)); 133 134 return (0); 135} 136 137static int 138iic_detach(device_t dev) 139{ 140 struct iic_softc *sc = (struct iic_softc *)device_get_softc(dev); 141 142 if (sc->sc_devnode) 143 destroy_dev(sc->sc_devnode); 144 145 return (0); 146} 147 148static int 149iicopen (struct cdev *dev, int flags, int fmt, struct thread *td) 150{ 151 struct iic_softc *sc = IIC_SOFTC(minor(dev)); 152 153 if (!sc) 154 return (EINVAL); 155 156 if (sc->sc_count > 0) 157 return (EBUSY); 158 159 sc->sc_count++; 160 161 return (0); 162} 163 164static int 165iicclose(struct cdev *dev, int flags, int fmt, struct thread *td) 166{ 167 struct iic_softc *sc = IIC_SOFTC(minor(dev)); 168 169 if (!sc) 170 return (EINVAL); 171 172 if (!sc->sc_count) 173 return (EINVAL); 174 175 sc->sc_count--; 176 177 if (sc->sc_count < 0) 178 panic("%s: iic_count < 0!", __func__); 179 180 return (0); 181} 182 183static int 184iicwrite(struct cdev *dev, struct uio * uio, int ioflag) 185{ 186 device_t iicdev = IIC_DEVICE(minor(dev)); 187 struct iic_softc *sc = IIC_SOFTC(minor(dev)); 188 int sent, error, count; 189 190 if (!sc || !iicdev || !sc->sc_addr) 191 return (EINVAL); 192 193 if (sc->sc_count == 0) 194 return (EINVAL); 195 196 if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev, IIC_DONTWAIT))) 197 return (error); 198 199 count = min(uio->uio_resid, BUFSIZE); 200 uiomove(sc->sc_buffer, count, uio); 201 202 error = iicbus_block_write(device_get_parent(iicdev), sc->sc_addr, 203 sc->sc_buffer, count, &sent); 204 205 iicbus_release_bus(device_get_parent(iicdev), iicdev); 206 207 return(error); 208} 209 210static int 211iicread(struct cdev *dev, struct uio * uio, int ioflag) 212{ 213 device_t iicdev = IIC_DEVICE(minor(dev)); 214 struct iic_softc *sc = IIC_SOFTC(minor(dev)); 215 int len, error = 0; 216 int bufsize; 217 218 if (!sc || !iicdev || !sc->sc_addr) 219 return (EINVAL); 220 221 if (sc->sc_count == 0) 222 return (EINVAL); 223 224 if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev, IIC_DONTWAIT))) 225 return (error); 226 227 /* max amount of data to read */ 228 len = min(uio->uio_resid, BUFSIZE); 229 230 if ((error = iicbus_block_read(device_get_parent(iicdev), sc->sc_addr, 231 sc->sc_inbuf, len, &bufsize))) 232 return (error); 233 234 if (bufsize > uio->uio_resid) 235 panic("%s: too much data read!", __func__); 236 237 iicbus_release_bus(device_get_parent(iicdev), iicdev); 238 239 return (uiomove(sc->sc_inbuf, bufsize, uio)); 240} 241 242static int 243iicioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags, struct thread *td) 244{ 245 device_t iicdev = IIC_DEVICE(minor(dev)); 246 struct iic_softc *sc = IIC_SOFTC(minor(dev)); 247 device_t parent = device_get_parent(iicdev); 248 struct iiccmd *s = (struct iiccmd *)data; 249 int error, count; 250 char *buf = NULL; 251 252 if (!sc) 253 return (EINVAL); 254 255 if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev, 256 (flags & O_NONBLOCK) ? IIC_DONTWAIT : 257 (IIC_WAIT | IIC_INTR)))) 258 return (error); 259 260 switch (cmd) { 261 case I2CSTART: 262 error = iicbus_start(parent, s->slave, 0); 263 264 /* 265 * Implicitly set the chip addr to the slave addr passed as 266 * parameter. Consequently, start/stop shall be called before 267 * the read or the write of a block. 268 */ 269 if (!error) 270 sc->sc_addr = s->slave; 271 272 break; 273 274 case I2CSTOP: 275 error = iicbus_stop(parent); 276 break; 277 278 case I2CRSTCARD: 279 error = iicbus_reset(parent, IIC_UNKNOWN, 0, NULL); 280 break; 281 282 case I2CWRITE: 283 if (s->count <= 0) { 284 error = EINVAL; 285 break; 286 } 287 buf = malloc((unsigned long)s->count, M_TEMP, M_WAITOK); 288 error = copyin(s->buf, buf, s->count); 289 if (error) 290 break; 291 error = iicbus_write(parent, buf, s->count, &count, 10); 292 break; 293 294 case I2CREAD: 295 if (s->count <= 0) { 296 error = EINVAL; 297 break; 298 } 299 buf = malloc((unsigned long)s->count, M_TEMP, M_WAITOK); 300 error = iicbus_read(parent, buf, s->count, &count, s->last, 10); 301 if (error) 302 break; 303 error = copyout(buf, s->buf, s->count); 304 break; 305 306 default: 307 error = ENOTTY; 308 } 309 310 iicbus_release_bus(device_get_parent(iicdev), iicdev); 311 312 if (buf != NULL) 313 free(buf, M_TEMP); 314 return (error); 315} 316 317DRIVER_MODULE(iic, iicbus, iic_driver, iic_devclass, 0, 0); 318MODULE_DEPEND(iic, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER); 319MODULE_VERSION(iic, 1); 320