1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Industry-pack bus support functions. 4 * 5 * Copyright (C) 2011-2012 CERN (www.cern.ch) 6 * Author: Samuel Iglesias Gonsalvez <siglesias@igalia.com> 7 */ 8 9 #include <linux/module.h> 10 #include <linux/slab.h> 11 #include <linux/idr.h> 12 #include <linux/io.h> 13 #include <linux/ipack.h> 14 15 #define to_ipack_dev(device) container_of(device, struct ipack_device, dev) 16 #define to_ipack_driver(drv) container_of(drv, struct ipack_driver, driver) 17 18 static DEFINE_IDA(ipack_ida); 19 20 static void ipack_device_release(struct device *dev) 21 { 22 struct ipack_device *device = to_ipack_dev(dev); 23 kfree(device->id); 24 device->release(device); 25 } 26 27 static inline const struct ipack_device_id * 28 ipack_match_one_device(const struct ipack_device_id *id, 29 const struct ipack_device *device) 30 { 31 if ((id->format == IPACK_ANY_FORMAT || 32 id->format == device->id_format) && 33 (id->vendor == IPACK_ANY_ID || id->vendor == device->id_vendor) && 34 (id->device == IPACK_ANY_ID || id->device == device->id_device)) 35 return id; 36 return NULL; 37 } 38 39 static const struct ipack_device_id * 40 ipack_match_id(const struct ipack_device_id *ids, struct ipack_device *idev) 41 { 42 if (ids) { 43 while (ids->vendor || ids->device) { 44 if (ipack_match_one_device(ids, idev)) 45 return ids; 46 ids++; 47 } 48 } 49 return NULL; 50 } 51 52 static int ipack_bus_match(struct device *dev, struct device_driver *drv) 53 { 54 struct ipack_device *idev = to_ipack_dev(dev); 55 struct ipack_driver *idrv = to_ipack_driver(drv); 56 const struct ipack_device_id *found_id; 57 58 found_id = ipack_match_id(idrv->id_table, idev); 59 return found_id ? 1 : 0; 60 } 61 62 static int ipack_bus_probe(struct device *device) 63 { 64 struct ipack_device *dev = to_ipack_dev(device); 65 struct ipack_driver *drv = to_ipack_driver(device->driver); 66 67 return drv->ops->probe(dev); 68 } 69 70 static void ipack_bus_remove(struct device *device) 71 { 72 struct ipack_device *dev = to_ipack_dev(device); 73 struct ipack_driver *drv = to_ipack_driver(device->driver); 74 75 if (drv->ops->remove) 76 drv->ops->remove(dev); 77 } 78 79 static int ipack_uevent(const struct device *dev, struct kobj_uevent_env *env) 80 { 81 const struct ipack_device *idev; 82 83 if (!dev) 84 return -ENODEV; 85 86 idev = to_ipack_dev(dev); 87 88 if (add_uevent_var(env, 89 "MODALIAS=ipack:f%02Xv%08Xd%08X", idev->id_format, 90 idev->id_vendor, idev->id_device)) 91 return -ENOMEM; 92 93 return 0; 94 } 95 96 #define ipack_device_attr(field, format_string) \ 97 static ssize_t \ 98 field##_show(struct device *dev, struct device_attribute *attr, \ 99 char *buf) \ 100 { \ 101 struct ipack_device *idev = to_ipack_dev(dev); \ 102 return sprintf(buf, format_string, idev->field); \ 103 } 104 105 static ssize_t id_show(struct device *dev, 106 struct device_attribute *attr, char *buf) 107 { 108 unsigned int i, c, l, s; 109 struct ipack_device *idev = to_ipack_dev(dev); 110 111 112 switch (idev->id_format) { 113 case IPACK_ID_VERSION_1: 114 l = 0x7; s = 1; break; 115 case IPACK_ID_VERSION_2: 116 l = 0xf; s = 2; break; 117 default: 118 return -EIO; 119 } 120 c = 0; 121 for (i = 0; i < idev->id_avail; i++) { 122 if (i > 0) { 123 if ((i & l) == 0) 124 buf[c++] = '\n'; 125 else if ((i & s) == 0) 126 buf[c++] = ' '; 127 } 128 sprintf(&buf[c], "%02x", idev->id[i]); 129 c += 2; 130 } 131 buf[c++] = '\n'; 132 return c; 133 } 134 135 static ssize_t 136 id_vendor_show(struct device *dev, struct device_attribute *attr, char *buf) 137 { 138 struct ipack_device *idev = to_ipack_dev(dev); 139 switch (idev->id_format) { 140 case IPACK_ID_VERSION_1: 141 return sprintf(buf, "0x%02x\n", idev->id_vendor); 142 case IPACK_ID_VERSION_2: 143 return sprintf(buf, "0x%06x\n", idev->id_vendor); 144 default: 145 return -EIO; 146 } 147 } 148 149 static ssize_t 150 id_device_show(struct device *dev, struct device_attribute *attr, char *buf) 151 { 152 struct ipack_device *idev = to_ipack_dev(dev); 153 switch (idev->id_format) { 154 case IPACK_ID_VERSION_1: 155 return sprintf(buf, "0x%02x\n", idev->id_device); 156 case IPACK_ID_VERSION_2: 157 return sprintf(buf, "0x%04x\n", idev->id_device); 158 default: 159 return -EIO; 160 } 161 } 162 163 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, 164 char *buf) 165 { 166 struct ipack_device *idev = to_ipack_dev(dev); 167 168 return sprintf(buf, "ipac:f%02Xv%08Xd%08X", idev->id_format, 169 idev->id_vendor, idev->id_device); 170 } 171 172 ipack_device_attr(id_format, "0x%hhx\n"); 173 174 static DEVICE_ATTR_RO(id); 175 static DEVICE_ATTR_RO(id_device); 176 static DEVICE_ATTR_RO(id_format); 177 static DEVICE_ATTR_RO(id_vendor); 178 static DEVICE_ATTR_RO(modalias); 179 180 static struct attribute *ipack_attrs[] = { 181 &dev_attr_id.attr, 182 &dev_attr_id_device.attr, 183 &dev_attr_id_format.attr, 184 &dev_attr_id_vendor.attr, 185 &dev_attr_modalias.attr, 186 NULL, 187 }; 188 ATTRIBUTE_GROUPS(ipack); 189 190 static struct bus_type ipack_bus_type = { 191 .name = "ipack", 192 .probe = ipack_bus_probe, 193 .match = ipack_bus_match, 194 .remove = ipack_bus_remove, 195 .dev_groups = ipack_groups, 196 .uevent = ipack_uevent, 197 }; 198 199 struct ipack_bus_device *ipack_bus_register(struct device *parent, int slots, 200 const struct ipack_bus_ops *ops, 201 struct module *owner) 202 { 203 int bus_nr; 204 struct ipack_bus_device *bus; 205 206 bus = kzalloc(sizeof(*bus), GFP_KERNEL); 207 if (!bus) 208 return NULL; 209 210 bus_nr = ida_simple_get(&ipack_ida, 0, 0, GFP_KERNEL); 211 if (bus_nr < 0) { 212 kfree(bus); 213 return NULL; 214 } 215 216 bus->bus_nr = bus_nr; 217 bus->parent = parent; 218 bus->slots = slots; 219 bus->ops = ops; 220 bus->owner = owner; 221 return bus; 222 } 223 EXPORT_SYMBOL_GPL(ipack_bus_register); 224 225 static int ipack_unregister_bus_member(struct device *dev, void *data) 226 { 227 struct ipack_device *idev = to_ipack_dev(dev); 228 struct ipack_bus_device *bus = data; 229 230 if (idev->bus == bus) 231 ipack_device_del(idev); 232 233 return 1; 234 } 235 236 int ipack_bus_unregister(struct ipack_bus_device *bus) 237 { 238 bus_for_each_dev(&ipack_bus_type, NULL, bus, 239 ipack_unregister_bus_member); 240 ida_simple_remove(&ipack_ida, bus->bus_nr); 241 kfree(bus); 242 return 0; 243 } 244 EXPORT_SYMBOL_GPL(ipack_bus_unregister); 245 246 int ipack_driver_register(struct ipack_driver *edrv, struct module *owner, 247 const char *name) 248 { 249 if (!edrv->ops->probe) 250 return -EINVAL; 251 252 edrv->driver.owner = owner; 253 edrv->driver.name = name; 254 edrv->driver.bus = &ipack_bus_type; 255 return driver_register(&edrv->driver); 256 } 257 EXPORT_SYMBOL_GPL(ipack_driver_register); 258 259 void ipack_driver_unregister(struct ipack_driver *edrv) 260 { 261 driver_unregister(&edrv->driver); 262 } 263 EXPORT_SYMBOL_GPL(ipack_driver_unregister); 264 265 static u16 ipack_crc_byte(u16 crc, u8 c) 266 { 267 int i; 268 269 crc ^= c << 8; 270 for (i = 0; i < 8; i++) 271 crc = (crc << 1) ^ ((crc & 0x8000) ? 0x1021 : 0); 272 return crc; 273 } 274 275 /* 276 * The algorithm in lib/crc-ccitt.c does not seem to apply since it uses the 277 * opposite bit ordering. 278 */ 279 static u8 ipack_calc_crc1(struct ipack_device *dev) 280 { 281 u8 c; 282 u16 crc; 283 unsigned int i; 284 285 crc = 0xffff; 286 for (i = 0; i < dev->id_avail; i++) { 287 c = (i != 11) ? dev->id[i] : 0; 288 crc = ipack_crc_byte(crc, c); 289 } 290 crc = ~crc; 291 return crc & 0xff; 292 } 293 294 static u16 ipack_calc_crc2(struct ipack_device *dev) 295 { 296 u8 c; 297 u16 crc; 298 unsigned int i; 299 300 crc = 0xffff; 301 for (i = 0; i < dev->id_avail; i++) { 302 c = ((i != 0x18) && (i != 0x19)) ? dev->id[i] : 0; 303 crc = ipack_crc_byte(crc, c); 304 } 305 crc = ~crc; 306 return crc; 307 } 308 309 static void ipack_parse_id1(struct ipack_device *dev) 310 { 311 u8 *id = dev->id; 312 u8 crc; 313 314 dev->id_vendor = id[4]; 315 dev->id_device = id[5]; 316 dev->speed_8mhz = 1; 317 dev->speed_32mhz = (id[7] == 'H'); 318 crc = ipack_calc_crc1(dev); 319 dev->id_crc_correct = (crc == id[11]); 320 if (!dev->id_crc_correct) { 321 dev_warn(&dev->dev, "ID CRC invalid found 0x%x, expected 0x%x.\n", 322 id[11], crc); 323 } 324 } 325 326 static void ipack_parse_id2(struct ipack_device *dev) 327 { 328 __be16 *id = (__be16 *) dev->id; 329 u16 flags, crc; 330 331 dev->id_vendor = ((be16_to_cpu(id[3]) & 0xff) << 16) 332 + be16_to_cpu(id[4]); 333 dev->id_device = be16_to_cpu(id[5]); 334 flags = be16_to_cpu(id[10]); 335 dev->speed_8mhz = !!(flags & 2); 336 dev->speed_32mhz = !!(flags & 4); 337 crc = ipack_calc_crc2(dev); 338 dev->id_crc_correct = (crc == be16_to_cpu(id[12])); 339 if (!dev->id_crc_correct) { 340 dev_warn(&dev->dev, "ID CRC invalid found 0x%x, expected 0x%x.\n", 341 id[11], crc); 342 } 343 } 344 345 static int ipack_device_read_id(struct ipack_device *dev) 346 { 347 u8 __iomem *idmem; 348 int i; 349 int ret = 0; 350 351 idmem = ioremap(dev->region[IPACK_ID_SPACE].start, 352 dev->region[IPACK_ID_SPACE].size); 353 if (!idmem) { 354 dev_err(&dev->dev, "error mapping memory\n"); 355 return -ENOMEM; 356 } 357 358 /* Determine ID PROM Data Format. If we find the ids "IPAC" or "IPAH" 359 * we are dealing with a IndustryPack format 1 device. If we detect 360 * "VITA4 " (16 bit big endian formatted) we are dealing with a 361 * IndustryPack format 2 device */ 362 if ((ioread8(idmem + 1) == 'I') && 363 (ioread8(idmem + 3) == 'P') && 364 (ioread8(idmem + 5) == 'A') && 365 ((ioread8(idmem + 7) == 'C') || 366 (ioread8(idmem + 7) == 'H'))) { 367 dev->id_format = IPACK_ID_VERSION_1; 368 dev->id_avail = ioread8(idmem + 0x15); 369 if ((dev->id_avail < 0x0c) || (dev->id_avail > 0x40)) { 370 dev_warn(&dev->dev, "invalid id size"); 371 dev->id_avail = 0x0c; 372 } 373 } else if ((ioread8(idmem + 0) == 'I') && 374 (ioread8(idmem + 1) == 'V') && 375 (ioread8(idmem + 2) == 'A') && 376 (ioread8(idmem + 3) == 'T') && 377 (ioread8(idmem + 4) == ' ') && 378 (ioread8(idmem + 5) == '4')) { 379 dev->id_format = IPACK_ID_VERSION_2; 380 dev->id_avail = ioread16be(idmem + 0x16); 381 if ((dev->id_avail < 0x1a) || (dev->id_avail > 0x40)) { 382 dev_warn(&dev->dev, "invalid id size"); 383 dev->id_avail = 0x1a; 384 } 385 } else { 386 dev->id_format = IPACK_ID_VERSION_INVALID; 387 dev->id_avail = 0; 388 } 389 390 if (!dev->id_avail) { 391 ret = -ENODEV; 392 goto out; 393 } 394 395 /* Obtain the amount of memory required to store a copy of the complete 396 * ID ROM contents */ 397 dev->id = kmalloc(dev->id_avail, GFP_KERNEL); 398 if (!dev->id) { 399 ret = -ENOMEM; 400 goto out; 401 } 402 for (i = 0; i < dev->id_avail; i++) { 403 if (dev->id_format == IPACK_ID_VERSION_1) 404 dev->id[i] = ioread8(idmem + (i << 1) + 1); 405 else 406 dev->id[i] = ioread8(idmem + i); 407 } 408 409 /* now we can finally work with the copy */ 410 switch (dev->id_format) { 411 case IPACK_ID_VERSION_1: 412 ipack_parse_id1(dev); 413 break; 414 case IPACK_ID_VERSION_2: 415 ipack_parse_id2(dev); 416 break; 417 } 418 419 out: 420 iounmap(idmem); 421 422 return ret; 423 } 424 425 int ipack_device_init(struct ipack_device *dev) 426 { 427 int ret; 428 429 dev->dev.bus = &ipack_bus_type; 430 dev->dev.release = ipack_device_release; 431 dev->dev.parent = dev->bus->parent; 432 ret = dev_set_name(&dev->dev, 433 "ipack-dev.%u.%u", dev->bus->bus_nr, dev->slot); 434 if (ret) 435 return ret; 436 437 device_initialize(&dev->dev); 438 439 if (dev->bus->ops->set_clockrate(dev, 8)) 440 dev_warn(&dev->dev, "failed to switch to 8 MHz operation for reading of device ID.\n"); 441 if (dev->bus->ops->reset_timeout(dev)) 442 dev_warn(&dev->dev, "failed to reset potential timeout."); 443 444 ret = ipack_device_read_id(dev); 445 if (ret < 0) { 446 dev_err(&dev->dev, "error reading device id section.\n"); 447 return ret; 448 } 449 450 /* if the device supports 32 MHz operation, use it. */ 451 if (dev->speed_32mhz) { 452 ret = dev->bus->ops->set_clockrate(dev, 32); 453 if (ret < 0) 454 dev_err(&dev->dev, "failed to switch to 32 MHz operation.\n"); 455 } 456 457 return 0; 458 } 459 EXPORT_SYMBOL_GPL(ipack_device_init); 460 461 int ipack_device_add(struct ipack_device *dev) 462 { 463 return device_add(&dev->dev); 464 } 465 EXPORT_SYMBOL_GPL(ipack_device_add); 466 467 void ipack_device_del(struct ipack_device *dev) 468 { 469 device_del(&dev->dev); 470 ipack_put_device(dev); 471 } 472 EXPORT_SYMBOL_GPL(ipack_device_del); 473 474 void ipack_get_device(struct ipack_device *dev) 475 { 476 get_device(&dev->dev); 477 } 478 EXPORT_SYMBOL_GPL(ipack_get_device); 479 480 void ipack_put_device(struct ipack_device *dev) 481 { 482 put_device(&dev->dev); 483 } 484 EXPORT_SYMBOL_GPL(ipack_put_device); 485 486 static int __init ipack_init(void) 487 { 488 ida_init(&ipack_ida); 489 return bus_register(&ipack_bus_type); 490 } 491 492 static void __exit ipack_exit(void) 493 { 494 bus_unregister(&ipack_bus_type); 495 ida_destroy(&ipack_ida); 496 } 497 498 module_init(ipack_init); 499 module_exit(ipack_exit); 500 501 MODULE_AUTHOR("Samuel Iglesias Gonsalvez <siglesias@igalia.com>"); 502 MODULE_LICENSE("GPL"); 503 MODULE_DESCRIPTION("Industry-pack bus core"); 504