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_const(drv, struct ipack_driver, driver)
17
18 static DEFINE_IDA(ipack_ida);
19
ipack_device_release(struct device * dev)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 *
ipack_match_one_device(const struct ipack_device_id * id,const struct ipack_device * device)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 *
ipack_match_id(const struct ipack_device_id * ids,struct ipack_device * idev)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
ipack_bus_match(struct device * dev,const struct device_driver * drv)52 static int ipack_bus_match(struct device *dev, const struct device_driver *drv)
53 {
54 struct ipack_device *idev = to_ipack_dev(dev);
55 const 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
ipack_bus_probe(struct device * device)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
ipack_bus_remove(struct device * device)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
ipack_uevent(const struct device * dev,struct kobj_uevent_env * env)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
id_show(struct device * dev,struct device_attribute * attr,char * buf)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
id_vendor_show(struct device * dev,struct device_attribute * attr,char * buf)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
id_device_show(struct device * dev,struct device_attribute * attr,char * buf)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
modalias_show(struct device * dev,struct device_attribute * attr,char * buf)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 const 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
ipack_bus_register(struct device * parent,int slots,const struct ipack_bus_ops * ops,struct module * owner)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_alloc(&ipack_ida, 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
ipack_unregister_bus_member(struct device * dev,void * data)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
ipack_bus_unregister(struct ipack_bus_device * bus)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_free(&ipack_ida, bus->bus_nr);
241 kfree(bus);
242 return 0;
243 }
244 EXPORT_SYMBOL_GPL(ipack_bus_unregister);
245
ipack_driver_register(struct ipack_driver * edrv,struct module * owner,const char * name)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
ipack_driver_unregister(struct ipack_driver * edrv)259 void ipack_driver_unregister(struct ipack_driver *edrv)
260 {
261 driver_unregister(&edrv->driver);
262 }
263 EXPORT_SYMBOL_GPL(ipack_driver_unregister);
264
ipack_crc_byte(u16 crc,u8 c)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 */
ipack_calc_crc1(struct ipack_device * dev)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
ipack_calc_crc2(struct ipack_device * dev)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
ipack_parse_id1(struct ipack_device * dev)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
ipack_parse_id2(struct ipack_device * dev)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
ipack_device_read_id(struct ipack_device * dev)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
ipack_device_init(struct ipack_device * dev)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
ipack_device_add(struct ipack_device * dev)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
ipack_device_del(struct ipack_device * dev)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
ipack_get_device(struct ipack_device * dev)474 void ipack_get_device(struct ipack_device *dev)
475 {
476 get_device(&dev->dev);
477 }
478 EXPORT_SYMBOL_GPL(ipack_get_device);
479
ipack_put_device(struct ipack_device * dev)480 void ipack_put_device(struct ipack_device *dev)
481 {
482 put_device(&dev->dev);
483 }
484 EXPORT_SYMBOL_GPL(ipack_put_device);
485
ipack_init(void)486 static int __init ipack_init(void)
487 {
488 ida_init(&ipack_ida);
489 return bus_register(&ipack_bus_type);
490 }
491
ipack_exit(void)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