1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2006 M. Warner Losh <imp@FreeBSD.org> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 /* 30 * Generic IIC eeprom support, modeled after the AT24C family of products. 31 */ 32 33 #include "opt_platform.h" 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/bus.h> 38 #include <sys/conf.h> 39 #include <sys/kernel.h> 40 #include <sys/module.h> 41 #include <sys/resource.h> 42 #include <sys/sx.h> 43 #include <sys/sysctl.h> 44 #include <sys/uio.h> 45 #include <machine/bus.h> 46 47 #ifdef FDT 48 #include <dev/ofw/ofw_bus.h> 49 #include <dev/ofw/ofw_bus_subr.h> 50 #endif 51 52 #include <dev/iicbus/iiconf.h> 53 #include <dev/iicbus/iicbus.h> 54 55 #include "iicbus_if.h" 56 57 /* 58 * AT24 parts have a "write page size" that differs per-device, and a "read page 59 * size" that is always equal to the full device size. We define maximum values 60 * here to limit how long we occupy the bus with a single transfer, and because 61 * there are temporary buffers of these sizes allocated on the stack. 62 */ 63 #define MAX_RD_SZ 256 /* Largest read size we support */ 64 #define MAX_WR_SZ 256 /* Largest write size we support */ 65 66 struct icee_softc { 67 device_t dev; /* Myself */ 68 struct cdev *cdev; /* user interface */ 69 int addr; /* Slave address on the bus */ 70 int size; /* How big am I? */ 71 int type; /* What address type 8 or 16 bit? */ 72 int wr_sz; /* What's the write page size */ 73 }; 74 75 #ifdef FDT 76 struct eeprom_desc { 77 int type; 78 int size; 79 int wr_sz; 80 const char *name; 81 }; 82 83 static struct eeprom_desc type_desc[] = { 84 { 8, 128, 8, "AT24C01"}, 85 { 8, 256, 8, "AT24C02"}, 86 { 8, 512, 16, "AT24C04"}, 87 { 8, 1024, 16, "AT24C08"}, 88 { 8, 2 * 1024, 16, "AT24C16"}, 89 {16, 4 * 1024, 32, "AT24C32"}, 90 {16, 8 * 1024, 32, "AT24C64"}, 91 {16, 16 * 1024, 64, "AT24C128"}, 92 {16, 32 * 1024, 64, "AT24C256"}, 93 {16, 64 * 1024, 128, "AT24C512"}, 94 {16, 128 * 1024, 256, "AT24CM01"}, 95 }; 96 97 static struct ofw_compat_data compat_data[] = { 98 {"atmel,24c01", (uintptr_t)(&type_desc[0])}, 99 {"atmel,24c02", (uintptr_t)(&type_desc[1])}, 100 {"atmel,24c04", (uintptr_t)(&type_desc[2])}, 101 {"atmel,24c08", (uintptr_t)(&type_desc[3])}, 102 {"atmel,24c16", (uintptr_t)(&type_desc[4])}, 103 {"atmel,24c32", (uintptr_t)(&type_desc[5])}, 104 {"atmel,24c64", (uintptr_t)(&type_desc[6])}, 105 {"atmel,24c128", (uintptr_t)(&type_desc[7])}, 106 {"atmel,24c256", (uintptr_t)(&type_desc[8])}, 107 {"atmel,24c512", (uintptr_t)(&type_desc[9])}, 108 {"atmel,24c1024", (uintptr_t)(&type_desc[10])}, 109 {NULL, (uintptr_t)NULL}, 110 }; 111 #endif 112 113 #define CDEV2SOFTC(dev) ((dev)->si_drv1) 114 115 /* cdev routines */ 116 static d_read_t icee_read; 117 static d_write_t icee_write; 118 119 static struct cdevsw icee_cdevsw = 120 { 121 .d_version = D_VERSION, 122 .d_read = icee_read, 123 .d_write = icee_write 124 }; 125 126 static int 127 icee_probe(device_t dev) 128 { 129 #ifdef FDT 130 struct eeprom_desc *d; 131 132 if (!ofw_bus_status_okay(dev)) 133 return (ENXIO); 134 135 d = (struct eeprom_desc *) 136 ofw_bus_search_compatible(dev, compat_data)->ocd_data; 137 if (d != NULL) { 138 device_set_desc(dev, d->name); 139 return (BUS_PROBE_DEFAULT); 140 } 141 #endif 142 device_set_desc(dev, "I2C EEPROM"); 143 return (BUS_PROBE_NOWILDCARD); 144 } 145 146 static int 147 icee_init(struct icee_softc *sc) 148 { 149 const char *dname; 150 int dunit; 151 #ifdef FDT 152 struct eeprom_desc *d; 153 154 d = (struct eeprom_desc *) 155 ofw_bus_search_compatible(sc->dev, compat_data)->ocd_data; 156 if (d != NULL) { 157 sc->size = d->size; 158 sc->type = d->type; 159 sc->wr_sz = d->wr_sz; 160 return (0); 161 } 162 #endif 163 dname = device_get_name(sc->dev); 164 dunit = device_get_unit(sc->dev); 165 if (resource_int_value(dname, dunit, "type", &sc->type) != 0) 166 return (ENOENT); 167 if (resource_int_value(dname, dunit, "size", &sc->size) != 0) 168 return (ENOENT); 169 if (resource_int_value(dname, dunit, "wr_sz", &sc->wr_sz) != 0) 170 return (ENOENT); 171 return (0); 172 } 173 174 static int 175 icee_attach(device_t dev) 176 { 177 struct icee_softc *sc = device_get_softc(dev); 178 struct sysctl_ctx_list *ctx; 179 struct sysctl_oid_list *tree; 180 181 sc->dev = dev; 182 sc->addr = iicbus_get_addr(dev); 183 if (icee_init(sc) != 0) 184 return (EINVAL); 185 if (bootverbose) 186 device_printf(dev, "size: %d bytes, addressing: %d-bits\n", 187 sc->size, sc->type); 188 sc->cdev = make_dev(&icee_cdevsw, device_get_unit(dev), UID_ROOT, 189 GID_WHEEL, 0600, "icee%d", device_get_unit(dev)); 190 if (sc->cdev == NULL) { 191 return (ENOMEM); 192 } 193 sc->cdev->si_drv1 = sc; 194 195 ctx = device_get_sysctl_ctx(dev); 196 tree = SYSCTL_CHILDREN(device_get_sysctl_tree(dev)); 197 SYSCTL_ADD_INT(ctx, tree, OID_AUTO, "address_size", CTLFLAG_RD, 198 &sc->type, 0, "Memory array address size in bits"); 199 SYSCTL_ADD_INT(ctx, tree, OID_AUTO, "device_size", CTLFLAG_RD, 200 &sc->size, 0, "Memory array capacity in bytes"); 201 SYSCTL_ADD_INT(ctx, tree, OID_AUTO, "write_size", CTLFLAG_RD, 202 &sc->wr_sz, 0, "Memory array page write size in bytes"); 203 204 return (0); 205 } 206 207 static int 208 icee_detach(device_t dev) 209 { 210 struct icee_softc *sc = device_get_softc(dev); 211 212 destroy_dev(sc->cdev); 213 return (0); 214 } 215 216 static int 217 icee_read(struct cdev *dev, struct uio *uio, int ioflag) 218 { 219 struct icee_softc *sc; 220 uint8_t addr[2]; 221 uint8_t data[MAX_RD_SZ]; 222 int error, i, len, slave; 223 struct iic_msg msgs[2] = { 224 { 0, IIC_M_WR, 1, addr }, 225 { 0, IIC_M_RD, 0, data }, 226 }; 227 228 sc = CDEV2SOFTC(dev); 229 if (uio->uio_offset == sc->size) 230 return (0); 231 if (uio->uio_offset > sc->size) 232 return (EIO); 233 if (sc->type != 8 && sc->type != 16) 234 return (EINVAL); 235 slave = error = 0; 236 while (uio->uio_resid > 0) { 237 if (uio->uio_offset >= sc->size) 238 break; 239 len = MIN(MAX_RD_SZ - (uio->uio_offset & (MAX_RD_SZ - 1)), 240 uio->uio_resid); 241 switch (sc->type) { 242 case 8: 243 slave = (uio->uio_offset >> 7) | sc->addr; 244 msgs[0].len = 1; 245 msgs[1].len = len; 246 addr[0] = uio->uio_offset & 0xff; 247 break; 248 case 16: 249 slave = sc->addr | (uio->uio_offset >> 15); 250 msgs[0].len = 2; 251 msgs[1].len = len; 252 addr[0] = (uio->uio_offset >> 8) & 0xff; 253 addr[1] = uio->uio_offset & 0xff; 254 break; 255 } 256 for (i = 0; i < 2; i++) 257 msgs[i].slave = slave; 258 error = iicbus_transfer_excl(sc->dev, msgs, 2, IIC_INTRWAIT); 259 if (error) { 260 error = iic2errno(error); 261 break; 262 } 263 error = uiomove(data, len, uio); 264 if (error) 265 break; 266 } 267 return (error); 268 } 269 270 /* 271 * Write to the part. We use three transfers here since we're actually 272 * doing a write followed by a read to make sure that the write finished. 273 * It is easier to encode the dummy read here than to break things up 274 * into smaller chunks... 275 */ 276 static int 277 icee_write(struct cdev *dev, struct uio *uio, int ioflag) 278 { 279 struct icee_softc *sc; 280 int error, len, slave, waitlimit; 281 uint8_t data[MAX_WR_SZ + 2]; 282 struct iic_msg wr[1] = { 283 { 0, IIC_M_WR, 0, data }, 284 }; 285 struct iic_msg rd[1] = { 286 { 0, IIC_M_RD, 1, data }, 287 }; 288 289 sc = CDEV2SOFTC(dev); 290 if (uio->uio_offset >= sc->size) 291 return (EIO); 292 if (sc->type != 8 && sc->type != 16) 293 return (EINVAL); 294 295 slave = error = 0; 296 while (uio->uio_resid > 0) { 297 if (uio->uio_offset >= sc->size) 298 break; 299 len = MIN(sc->wr_sz - (uio->uio_offset & (sc->wr_sz - 1)), 300 uio->uio_resid); 301 switch (sc->type) { 302 case 8: 303 slave = (uio->uio_offset >> 7) | sc->addr; 304 wr[0].len = 1 + len; 305 data[0] = uio->uio_offset & 0xff; 306 break; 307 case 16: 308 slave = sc->addr | (uio->uio_offset >> 15); 309 wr[0].len = 2 + len; 310 data[0] = (uio->uio_offset >> 8) & 0xff; 311 data[1] = uio->uio_offset & 0xff; 312 break; 313 } 314 wr[0].slave = slave; 315 error = uiomove(data + sc->type / 8, len, uio); 316 if (error) 317 break; 318 error = iicbus_transfer_excl(sc->dev, wr, 1, IIC_INTRWAIT); 319 if (error) { 320 error = iic2errno(error); 321 break; 322 } 323 /* Read after write to wait for write-done. */ 324 waitlimit = 10000; 325 rd[0].slave = slave; 326 do { 327 error = iicbus_transfer_excl(sc->dev, rd, 1, 328 IIC_INTRWAIT); 329 } while (waitlimit-- > 0 && error != 0); 330 if (error) { 331 error = iic2errno(error); 332 break; 333 } 334 } 335 return error; 336 } 337 338 static device_method_t icee_methods[] = { 339 DEVMETHOD(device_probe, icee_probe), 340 DEVMETHOD(device_attach, icee_attach), 341 DEVMETHOD(device_detach, icee_detach), 342 343 DEVMETHOD_END 344 }; 345 346 static driver_t icee_driver = { 347 "icee", 348 icee_methods, 349 sizeof(struct icee_softc), 350 }; 351 352 DRIVER_MODULE(icee, iicbus, icee_driver, 0, 0); 353 MODULE_VERSION(icee, 1); 354 MODULE_DEPEND(icee, iicbus, 1, 1, 1); 355 IICBUS_FDT_PNP_INFO(compat_data); 356