1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 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 /* 29 * Generic IIC eeprom support, modeled after the AT24C family of products. 30 */ 31 32 #include "opt_platform.h" 33 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 #include <sys/bus.h> 37 #include <sys/conf.h> 38 #include <sys/kernel.h> 39 #include <sys/module.h> 40 #include <sys/resource.h> 41 #include <sys/sx.h> 42 #include <sys/sysctl.h> 43 #include <sys/uio.h> 44 #include <machine/bus.h> 45 46 #ifdef FDT 47 #include <dev/ofw/ofw_bus.h> 48 #include <dev/ofw/ofw_bus_subr.h> 49 #endif 50 51 #include <dev/iicbus/iiconf.h> 52 #include <dev/iicbus/iicbus.h> 53 54 #include "iicbus_if.h" 55 56 /* 57 * AT24 parts have a "write page size" that differs per-device, and a "read page 58 * size" that is always equal to the full device size. We define maximum values 59 * here to limit how long we occupy the bus with a single transfer, and because 60 * there are temporary buffers of these sizes allocated on the stack. 61 */ 62 #define MAX_RD_SZ 256 /* Largest read size we support */ 63 #define MAX_WR_SZ 256 /* Largest write size we support */ 64 65 struct icee_softc { 66 device_t dev; /* Myself */ 67 struct cdev *cdev; /* user interface */ 68 int addr; /* Slave address on the bus */ 69 int size; /* How big am I? */ 70 int type; /* What address type 8 or 16 bit? */ 71 int wr_sz; /* What's the write page size */ 72 }; 73 74 #ifdef FDT 75 struct eeprom_desc { 76 int type; 77 int size; 78 int wr_sz; 79 const char *name; 80 }; 81 82 static struct eeprom_desc type_desc[] = { 83 { 8, 128, 8, "AT24C01"}, 84 { 8, 256, 8, "AT24C02"}, 85 { 8, 512, 16, "AT24C04"}, 86 { 8, 1024, 16, "AT24C08"}, 87 { 8, 2 * 1024, 16, "AT24C16"}, 88 {16, 4 * 1024, 32, "AT24C32"}, 89 {16, 8 * 1024, 32, "AT24C64"}, 90 {16, 16 * 1024, 64, "AT24C128"}, 91 {16, 32 * 1024, 64, "AT24C256"}, 92 {16, 64 * 1024, 128, "AT24C512"}, 93 {16, 128 * 1024, 256, "AT24CM01"}, 94 }; 95 96 static struct ofw_compat_data compat_data[] = { 97 {"atmel,24c01", (uintptr_t)(&type_desc[0])}, 98 {"atmel,24c02", (uintptr_t)(&type_desc[1])}, 99 {"atmel,24c04", (uintptr_t)(&type_desc[2])}, 100 {"atmel,24c08", (uintptr_t)(&type_desc[3])}, 101 {"atmel,24c16", (uintptr_t)(&type_desc[4])}, 102 {"atmel,24c32", (uintptr_t)(&type_desc[5])}, 103 {"atmel,24c64", (uintptr_t)(&type_desc[6])}, 104 {"atmel,24c128", (uintptr_t)(&type_desc[7])}, 105 {"atmel,24c256", (uintptr_t)(&type_desc[8])}, 106 {"atmel,24c512", (uintptr_t)(&type_desc[9])}, 107 {"atmel,24c1024", (uintptr_t)(&type_desc[10])}, 108 {NULL, (uintptr_t)NULL}, 109 }; 110 #endif 111 112 #define CDEV2SOFTC(dev) ((dev)->si_drv1) 113 114 /* cdev routines */ 115 static d_read_t icee_read; 116 static d_write_t icee_write; 117 118 static struct cdevsw icee_cdevsw = 119 { 120 .d_version = D_VERSION, 121 .d_read = icee_read, 122 .d_write = icee_write 123 }; 124 125 static int 126 icee_probe(device_t dev) 127 { 128 #ifdef FDT 129 struct eeprom_desc *d; 130 131 if (!ofw_bus_status_okay(dev)) 132 return (ENXIO); 133 134 d = (struct eeprom_desc *) 135 ofw_bus_search_compatible(dev, compat_data)->ocd_data; 136 if (d != NULL) { 137 device_set_desc(dev, d->name); 138 return (BUS_PROBE_DEFAULT); 139 } 140 #endif 141 device_set_desc(dev, "I2C EEPROM"); 142 return (BUS_PROBE_NOWILDCARD); 143 } 144 145 static int 146 icee_init(struct icee_softc *sc) 147 { 148 const char *dname; 149 int dunit; 150 #ifdef FDT 151 struct eeprom_desc *d; 152 153 d = (struct eeprom_desc *) 154 ofw_bus_search_compatible(sc->dev, compat_data)->ocd_data; 155 if (d != NULL) { 156 sc->size = d->size; 157 sc->type = d->type; 158 sc->wr_sz = d->wr_sz; 159 return (0); 160 } 161 #endif 162 dname = device_get_name(sc->dev); 163 dunit = device_get_unit(sc->dev); 164 if (resource_int_value(dname, dunit, "type", &sc->type) != 0) 165 return (ENOENT); 166 if (resource_int_value(dname, dunit, "size", &sc->size) != 0) 167 return (ENOENT); 168 if (resource_int_value(dname, dunit, "wr_sz", &sc->wr_sz) != 0) 169 return (ENOENT); 170 return (0); 171 } 172 173 static int 174 icee_attach(device_t dev) 175 { 176 struct icee_softc *sc = device_get_softc(dev); 177 struct sysctl_ctx_list *ctx; 178 struct sysctl_oid_list *tree; 179 180 sc->dev = dev; 181 sc->addr = iicbus_get_addr(dev); 182 if (icee_init(sc) != 0) 183 return (EINVAL); 184 if (bootverbose) 185 device_printf(dev, "size: %d bytes, addressing: %d-bits\n", 186 sc->size, sc->type); 187 sc->cdev = make_dev(&icee_cdevsw, device_get_unit(dev), UID_ROOT, 188 GID_WHEEL, 0600, "icee%d", device_get_unit(dev)); 189 if (sc->cdev == NULL) { 190 return (ENOMEM); 191 } 192 sc->cdev->si_drv1 = sc; 193 194 ctx = device_get_sysctl_ctx(dev); 195 tree = SYSCTL_CHILDREN(device_get_sysctl_tree(dev)); 196 SYSCTL_ADD_INT(ctx, tree, OID_AUTO, "address_size", CTLFLAG_RD, 197 &sc->type, 0, "Memory array address size in bits"); 198 SYSCTL_ADD_INT(ctx, tree, OID_AUTO, "device_size", CTLFLAG_RD, 199 &sc->size, 0, "Memory array capacity in bytes"); 200 SYSCTL_ADD_INT(ctx, tree, OID_AUTO, "write_size", CTLFLAG_RD, 201 &sc->wr_sz, 0, "Memory array page write size in bytes"); 202 203 return (0); 204 } 205 206 static int 207 icee_detach(device_t dev) 208 { 209 struct icee_softc *sc = device_get_softc(dev); 210 211 destroy_dev(sc->cdev); 212 return (0); 213 } 214 215 static int 216 icee_read(struct cdev *dev, struct uio *uio, int ioflag) 217 { 218 struct icee_softc *sc; 219 uint8_t addr[2]; 220 uint8_t data[MAX_RD_SZ]; 221 int error, i, len, slave; 222 struct iic_msg msgs[2] = { 223 { 0, IIC_M_WR, 1, addr }, 224 { 0, IIC_M_RD, 0, data }, 225 }; 226 227 sc = CDEV2SOFTC(dev); 228 if (uio->uio_offset == sc->size) 229 return (0); 230 if (uio->uio_offset > sc->size) 231 return (EIO); 232 if (sc->type != 8 && sc->type != 16) 233 return (EINVAL); 234 slave = error = 0; 235 while (uio->uio_resid > 0) { 236 if (uio->uio_offset >= sc->size) 237 break; 238 len = MIN(MAX_RD_SZ - (uio->uio_offset & (MAX_RD_SZ - 1)), 239 uio->uio_resid); 240 switch (sc->type) { 241 case 8: 242 slave = (uio->uio_offset >> 7) | sc->addr; 243 msgs[0].len = 1; 244 msgs[1].len = len; 245 addr[0] = uio->uio_offset & 0xff; 246 break; 247 case 16: 248 slave = sc->addr | (uio->uio_offset >> 15); 249 msgs[0].len = 2; 250 msgs[1].len = len; 251 addr[0] = (uio->uio_offset >> 8) & 0xff; 252 addr[1] = uio->uio_offset & 0xff; 253 break; 254 } 255 for (i = 0; i < 2; i++) 256 msgs[i].slave = slave; 257 error = iicbus_transfer_excl(sc->dev, msgs, 2, IIC_INTRWAIT); 258 if (error) { 259 error = iic2errno(error); 260 break; 261 } 262 error = uiomove(data, len, uio); 263 if (error) 264 break; 265 } 266 return (error); 267 } 268 269 /* 270 * Write to the part. We use three transfers here since we're actually 271 * doing a write followed by a read to make sure that the write finished. 272 * It is easier to encode the dummy read here than to break things up 273 * into smaller chunks... 274 */ 275 static int 276 icee_write(struct cdev *dev, struct uio *uio, int ioflag) 277 { 278 struct icee_softc *sc; 279 int error, len, slave, waitlimit; 280 uint8_t data[MAX_WR_SZ + 2]; 281 struct iic_msg wr[1] = { 282 { 0, IIC_M_WR, 0, data }, 283 }; 284 struct iic_msg rd[1] = { 285 { 0, IIC_M_RD, 1, data }, 286 }; 287 288 sc = CDEV2SOFTC(dev); 289 if (uio->uio_offset >= sc->size) 290 return (EIO); 291 if (sc->type != 8 && sc->type != 16) 292 return (EINVAL); 293 294 slave = error = 0; 295 while (uio->uio_resid > 0) { 296 if (uio->uio_offset >= sc->size) 297 break; 298 len = MIN(sc->wr_sz - (uio->uio_offset & (sc->wr_sz - 1)), 299 uio->uio_resid); 300 switch (sc->type) { 301 case 8: 302 slave = (uio->uio_offset >> 7) | sc->addr; 303 wr[0].len = 1 + len; 304 data[0] = uio->uio_offset & 0xff; 305 break; 306 case 16: 307 slave = sc->addr | (uio->uio_offset >> 15); 308 wr[0].len = 2 + len; 309 data[0] = (uio->uio_offset >> 8) & 0xff; 310 data[1] = uio->uio_offset & 0xff; 311 break; 312 } 313 wr[0].slave = slave; 314 error = uiomove(data + sc->type / 8, len, uio); 315 if (error) 316 break; 317 error = iicbus_transfer_excl(sc->dev, wr, 1, IIC_INTRWAIT); 318 if (error) { 319 error = iic2errno(error); 320 break; 321 } 322 /* Read after write to wait for write-done. */ 323 waitlimit = 10000; 324 rd[0].slave = slave; 325 do { 326 error = iicbus_transfer_excl(sc->dev, rd, 1, 327 IIC_INTRWAIT); 328 } while (waitlimit-- > 0 && error != 0); 329 if (error) { 330 error = iic2errno(error); 331 break; 332 } 333 } 334 return error; 335 } 336 337 static device_method_t icee_methods[] = { 338 DEVMETHOD(device_probe, icee_probe), 339 DEVMETHOD(device_attach, icee_attach), 340 DEVMETHOD(device_detach, icee_detach), 341 342 DEVMETHOD_END 343 }; 344 345 static driver_t icee_driver = { 346 "icee", 347 icee_methods, 348 sizeof(struct icee_softc), 349 }; 350 351 DRIVER_MODULE(icee, iicbus, icee_driver, 0, 0); 352 MODULE_VERSION(icee, 1); 353 MODULE_DEPEND(icee, iicbus, 1, 1, 1); 354 IICBUS_FDT_PNP_INFO(compat_data); 355