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
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,struct device_driver * drv)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
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 if (!drv->ops->probe)
68 return -EINVAL;
69
70 return drv->ops->probe(dev);
71 }
72
ipack_bus_remove(struct device * device)73 static int ipack_bus_remove(struct device *device)
74 {
75 struct ipack_device *dev = to_ipack_dev(device);
76 struct ipack_driver *drv = to_ipack_driver(device->driver);
77
78 if (!drv->ops->remove)
79 return -EINVAL;
80
81 drv->ops->remove(dev);
82 return 0;
83 }
84
ipack_uevent(struct device * dev,struct kobj_uevent_env * env)85 static int ipack_uevent(struct device *dev, struct kobj_uevent_env *env)
86 {
87 struct ipack_device *idev;
88
89 if (!dev)
90 return -ENODEV;
91
92 idev = to_ipack_dev(dev);
93
94 if (add_uevent_var(env,
95 "MODALIAS=ipack:f%02Xv%08Xd%08X", idev->id_format,
96 idev->id_vendor, idev->id_device))
97 return -ENOMEM;
98
99 return 0;
100 }
101
102 #define ipack_device_attr(field, format_string) \
103 static ssize_t \
104 field##_show(struct device *dev, struct device_attribute *attr, \
105 char *buf) \
106 { \
107 struct ipack_device *idev = to_ipack_dev(dev); \
108 return sprintf(buf, format_string, idev->field); \
109 }
110
id_show(struct device * dev,struct device_attribute * attr,char * buf)111 static ssize_t id_show(struct device *dev,
112 struct device_attribute *attr, char *buf)
113 {
114 unsigned int i, c, l, s;
115 struct ipack_device *idev = to_ipack_dev(dev);
116
117
118 switch (idev->id_format) {
119 case IPACK_ID_VERSION_1:
120 l = 0x7; s = 1; break;
121 case IPACK_ID_VERSION_2:
122 l = 0xf; s = 2; break;
123 default:
124 return -EIO;
125 }
126 c = 0;
127 for (i = 0; i < idev->id_avail; i++) {
128 if (i > 0) {
129 if ((i & l) == 0)
130 buf[c++] = '\n';
131 else if ((i & s) == 0)
132 buf[c++] = ' ';
133 }
134 sprintf(&buf[c], "%02x", idev->id[i]);
135 c += 2;
136 }
137 buf[c++] = '\n';
138 return c;
139 }
140
141 static ssize_t
id_vendor_show(struct device * dev,struct device_attribute * attr,char * buf)142 id_vendor_show(struct device *dev, struct device_attribute *attr, char *buf)
143 {
144 struct ipack_device *idev = to_ipack_dev(dev);
145 switch (idev->id_format) {
146 case IPACK_ID_VERSION_1:
147 return sprintf(buf, "0x%02x\n", idev->id_vendor);
148 case IPACK_ID_VERSION_2:
149 return sprintf(buf, "0x%06x\n", idev->id_vendor);
150 default:
151 return -EIO;
152 }
153 }
154
155 static ssize_t
id_device_show(struct device * dev,struct device_attribute * attr,char * buf)156 id_device_show(struct device *dev, struct device_attribute *attr, char *buf)
157 {
158 struct ipack_device *idev = to_ipack_dev(dev);
159 switch (idev->id_format) {
160 case IPACK_ID_VERSION_1:
161 return sprintf(buf, "0x%02x\n", idev->id_device);
162 case IPACK_ID_VERSION_2:
163 return sprintf(buf, "0x%04x\n", idev->id_device);
164 default:
165 return -EIO;
166 }
167 }
168
modalias_show(struct device * dev,struct device_attribute * attr,char * buf)169 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
170 char *buf)
171 {
172 struct ipack_device *idev = to_ipack_dev(dev);
173
174 return sprintf(buf, "ipac:f%02Xv%08Xd%08X", idev->id_format,
175 idev->id_vendor, idev->id_device);
176 }
177
178 ipack_device_attr(id_format, "0x%hhx\n");
179
180 static DEVICE_ATTR_RO(id);
181 static DEVICE_ATTR_RO(id_device);
182 static DEVICE_ATTR_RO(id_format);
183 static DEVICE_ATTR_RO(id_vendor);
184 static DEVICE_ATTR_RO(modalias);
185
186 static struct attribute *ipack_attrs[] = {
187 &dev_attr_id.attr,
188 &dev_attr_id_device.attr,
189 &dev_attr_id_format.attr,
190 &dev_attr_id_vendor.attr,
191 &dev_attr_modalias.attr,
192 NULL,
193 };
194 ATTRIBUTE_GROUPS(ipack);
195
196 static struct bus_type ipack_bus_type = {
197 .name = "ipack",
198 .probe = ipack_bus_probe,
199 .match = ipack_bus_match,
200 .remove = ipack_bus_remove,
201 .dev_groups = ipack_groups,
202 .uevent = ipack_uevent,
203 };
204
ipack_bus_register(struct device * parent,int slots,const struct ipack_bus_ops * ops,struct module * owner)205 struct ipack_bus_device *ipack_bus_register(struct device *parent, int slots,
206 const struct ipack_bus_ops *ops,
207 struct module *owner)
208 {
209 int bus_nr;
210 struct ipack_bus_device *bus;
211
212 bus = kzalloc(sizeof(*bus), GFP_KERNEL);
213 if (!bus)
214 return NULL;
215
216 bus_nr = ida_simple_get(&ipack_ida, 0, 0, GFP_KERNEL);
217 if (bus_nr < 0) {
218 kfree(bus);
219 return NULL;
220 }
221
222 bus->bus_nr = bus_nr;
223 bus->parent = parent;
224 bus->slots = slots;
225 bus->ops = ops;
226 bus->owner = owner;
227 return bus;
228 }
229 EXPORT_SYMBOL_GPL(ipack_bus_register);
230
ipack_unregister_bus_member(struct device * dev,void * data)231 static int ipack_unregister_bus_member(struct device *dev, void *data)
232 {
233 struct ipack_device *idev = to_ipack_dev(dev);
234 struct ipack_bus_device *bus = data;
235
236 if (idev->bus == bus)
237 ipack_device_del(idev);
238
239 return 1;
240 }
241
ipack_bus_unregister(struct ipack_bus_device * bus)242 int ipack_bus_unregister(struct ipack_bus_device *bus)
243 {
244 bus_for_each_dev(&ipack_bus_type, NULL, bus,
245 ipack_unregister_bus_member);
246 ida_simple_remove(&ipack_ida, bus->bus_nr);
247 kfree(bus);
248 return 0;
249 }
250 EXPORT_SYMBOL_GPL(ipack_bus_unregister);
251
ipack_driver_register(struct ipack_driver * edrv,struct module * owner,const char * name)252 int ipack_driver_register(struct ipack_driver *edrv, struct module *owner,
253 const char *name)
254 {
255 edrv->driver.owner = owner;
256 edrv->driver.name = name;
257 edrv->driver.bus = &ipack_bus_type;
258 return driver_register(&edrv->driver);
259 }
260 EXPORT_SYMBOL_GPL(ipack_driver_register);
261
ipack_driver_unregister(struct ipack_driver * edrv)262 void ipack_driver_unregister(struct ipack_driver *edrv)
263 {
264 driver_unregister(&edrv->driver);
265 }
266 EXPORT_SYMBOL_GPL(ipack_driver_unregister);
267
ipack_crc_byte(u16 crc,u8 c)268 static u16 ipack_crc_byte(u16 crc, u8 c)
269 {
270 int i;
271
272 crc ^= c << 8;
273 for (i = 0; i < 8; i++)
274 crc = (crc << 1) ^ ((crc & 0x8000) ? 0x1021 : 0);
275 return crc;
276 }
277
278 /*
279 * The algorithm in lib/crc-ccitt.c does not seem to apply since it uses the
280 * opposite bit ordering.
281 */
ipack_calc_crc1(struct ipack_device * dev)282 static u8 ipack_calc_crc1(struct ipack_device *dev)
283 {
284 u8 c;
285 u16 crc;
286 unsigned int i;
287
288 crc = 0xffff;
289 for (i = 0; i < dev->id_avail; i++) {
290 c = (i != 11) ? dev->id[i] : 0;
291 crc = ipack_crc_byte(crc, c);
292 }
293 crc = ~crc;
294 return crc & 0xff;
295 }
296
ipack_calc_crc2(struct ipack_device * dev)297 static u16 ipack_calc_crc2(struct ipack_device *dev)
298 {
299 u8 c;
300 u16 crc;
301 unsigned int i;
302
303 crc = 0xffff;
304 for (i = 0; i < dev->id_avail; i++) {
305 c = ((i != 0x18) && (i != 0x19)) ? dev->id[i] : 0;
306 crc = ipack_crc_byte(crc, c);
307 }
308 crc = ~crc;
309 return crc;
310 }
311
ipack_parse_id1(struct ipack_device * dev)312 static void ipack_parse_id1(struct ipack_device *dev)
313 {
314 u8 *id = dev->id;
315 u8 crc;
316
317 dev->id_vendor = id[4];
318 dev->id_device = id[5];
319 dev->speed_8mhz = 1;
320 dev->speed_32mhz = (id[7] == 'H');
321 crc = ipack_calc_crc1(dev);
322 dev->id_crc_correct = (crc == id[11]);
323 if (!dev->id_crc_correct) {
324 dev_warn(&dev->dev, "ID CRC invalid found 0x%x, expected 0x%x.\n",
325 id[11], crc);
326 }
327 }
328
ipack_parse_id2(struct ipack_device * dev)329 static void ipack_parse_id2(struct ipack_device *dev)
330 {
331 __be16 *id = (__be16 *) dev->id;
332 u16 flags, crc;
333
334 dev->id_vendor = ((be16_to_cpu(id[3]) & 0xff) << 16)
335 + be16_to_cpu(id[4]);
336 dev->id_device = be16_to_cpu(id[5]);
337 flags = be16_to_cpu(id[10]);
338 dev->speed_8mhz = !!(flags & 2);
339 dev->speed_32mhz = !!(flags & 4);
340 crc = ipack_calc_crc2(dev);
341 dev->id_crc_correct = (crc == be16_to_cpu(id[12]));
342 if (!dev->id_crc_correct) {
343 dev_warn(&dev->dev, "ID CRC invalid found 0x%x, expected 0x%x.\n",
344 id[11], crc);
345 }
346 }
347
ipack_device_read_id(struct ipack_device * dev)348 static int ipack_device_read_id(struct ipack_device *dev)
349 {
350 u8 __iomem *idmem;
351 int i;
352 int ret = 0;
353
354 idmem = ioremap(dev->region[IPACK_ID_SPACE].start,
355 dev->region[IPACK_ID_SPACE].size);
356 if (!idmem) {
357 dev_err(&dev->dev, "error mapping memory\n");
358 return -ENOMEM;
359 }
360
361 /* Determine ID PROM Data Format. If we find the ids "IPAC" or "IPAH"
362 * we are dealing with a IndustryPack format 1 device. If we detect
363 * "VITA4 " (16 bit big endian formatted) we are dealing with a
364 * IndustryPack format 2 device */
365 if ((ioread8(idmem + 1) == 'I') &&
366 (ioread8(idmem + 3) == 'P') &&
367 (ioread8(idmem + 5) == 'A') &&
368 ((ioread8(idmem + 7) == 'C') ||
369 (ioread8(idmem + 7) == 'H'))) {
370 dev->id_format = IPACK_ID_VERSION_1;
371 dev->id_avail = ioread8(idmem + 0x15);
372 if ((dev->id_avail < 0x0c) || (dev->id_avail > 0x40)) {
373 dev_warn(&dev->dev, "invalid id size");
374 dev->id_avail = 0x0c;
375 }
376 } else if ((ioread8(idmem + 0) == 'I') &&
377 (ioread8(idmem + 1) == 'V') &&
378 (ioread8(idmem + 2) == 'A') &&
379 (ioread8(idmem + 3) == 'T') &&
380 (ioread8(idmem + 4) == ' ') &&
381 (ioread8(idmem + 5) == '4')) {
382 dev->id_format = IPACK_ID_VERSION_2;
383 dev->id_avail = ioread16be(idmem + 0x16);
384 if ((dev->id_avail < 0x1a) || (dev->id_avail > 0x40)) {
385 dev_warn(&dev->dev, "invalid id size");
386 dev->id_avail = 0x1a;
387 }
388 } else {
389 dev->id_format = IPACK_ID_VERSION_INVALID;
390 dev->id_avail = 0;
391 }
392
393 if (!dev->id_avail) {
394 ret = -ENODEV;
395 goto out;
396 }
397
398 /* Obtain the amount of memory required to store a copy of the complete
399 * ID ROM contents */
400 dev->id = kmalloc(dev->id_avail, GFP_KERNEL);
401 if (!dev->id) {
402 ret = -ENOMEM;
403 goto out;
404 }
405 for (i = 0; i < dev->id_avail; i++) {
406 if (dev->id_format == IPACK_ID_VERSION_1)
407 dev->id[i] = ioread8(idmem + (i << 1) + 1);
408 else
409 dev->id[i] = ioread8(idmem + i);
410 }
411
412 /* now we can finally work with the copy */
413 switch (dev->id_format) {
414 case IPACK_ID_VERSION_1:
415 ipack_parse_id1(dev);
416 break;
417 case IPACK_ID_VERSION_2:
418 ipack_parse_id2(dev);
419 break;
420 }
421
422 out:
423 iounmap(idmem);
424
425 return ret;
426 }
427
ipack_device_init(struct ipack_device * dev)428 int ipack_device_init(struct ipack_device *dev)
429 {
430 int ret;
431
432 dev->dev.bus = &ipack_bus_type;
433 dev->dev.release = ipack_device_release;
434 dev->dev.parent = dev->bus->parent;
435 dev_set_name(&dev->dev,
436 "ipack-dev.%u.%u", dev->bus->bus_nr, dev->slot);
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