1/*
2 * Industry-pack bus support functions.
3 *
4 * Copyright (C) 2011-2012 CERN (www.cern.ch)
5 * Author: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the Free
9 * Software Foundation; version 2 of the License.
10 */
11
12#include <linux/module.h>
13#include <linux/slab.h>
14#include <linux/idr.h>
15#include <linux/io.h>
16#include <linux/ipack.h>
17
18#define to_ipack_dev(device) container_of(device, struct ipack_device, dev)
19#define to_ipack_driver(drv) container_of(drv, struct ipack_driver, driver)
20
21static DEFINE_IDA(ipack_ida);
22
23static void ipack_device_release(struct device *dev)
24{
25 struct ipack_device *device = to_ipack_dev(dev);
26 kfree(device->id);
27 device->release(device);
28}
29
30static inline const struct ipack_device_id *
31ipack_match_one_device(const struct ipack_device_id *id,
32 const struct ipack_device *device)
33{
34 if ((id->format == IPACK_ANY_FORMAT ||
35 id->format == device->id_format) &&
36 (id->vendor == IPACK_ANY_ID || id->vendor == device->id_vendor) &&
37 (id->device == IPACK_ANY_ID || id->device == device->id_device))
38 return id;
39 return NULL;
40}
41
42static const struct ipack_device_id *
43ipack_match_id(const struct ipack_device_id *ids, struct ipack_device *idev)
44{
45 if (ids) {
46 while (ids->vendor || ids->device) {
47 if (ipack_match_one_device(ids, idev))
48 return ids;
49 ids++;
50 }
51 }
52 return NULL;
53}
54
55static int ipack_bus_match(struct device *dev, struct device_driver *drv)
56{
57 struct ipack_device *idev = to_ipack_dev(dev);
58 struct ipack_driver *idrv = to_ipack_driver(drv);
59 const struct ipack_device_id *found_id;
60
61 found_id = ipack_match_id(idrv->id_table, idev);
62 return found_id ? 1 : 0;
63}
64
65static int ipack_bus_probe(struct device *device)
66{
67 struct ipack_device *dev = to_ipack_dev(device);
68 struct ipack_driver *drv = to_ipack_driver(device->driver);
69
70 if (!drv->ops->probe)
71 return -EINVAL;
72
73 return drv->ops->probe(dev);
74}
75
76static int ipack_bus_remove(struct device *device)
77{
78 struct ipack_device *dev = to_ipack_dev(device);
79 struct ipack_driver *drv = to_ipack_driver(device->driver);
80
81 if (!drv->ops->remove)
82 return -EINVAL;
83
84 drv->ops->remove(dev);
85 return 0;
86}
87
88static int ipack_uevent(struct device *dev, struct kobj_uevent_env *env)
89{
90 struct ipack_device *idev;
91
92 if (!dev)
93 return -ENODEV;
94
95 idev = to_ipack_dev(dev);
96
97 if (add_uevent_var(env,
98 "MODALIAS=ipack:f%02Xv%08Xd%08X", idev->id_format,
99 idev->id_vendor, idev->id_device))
100 return -ENOMEM;
101
102 return 0;
103}
104
105#define ipack_device_attr(field, format_string) \
106static ssize_t \
107field##_show(struct device *dev, struct device_attribute *attr, \
108 char *buf) \
109{ \
110 struct ipack_device *idev = to_ipack_dev(dev); \
111 return sprintf(buf, format_string, idev->field); \
112}
113
114static ssize_t id_show(struct device *dev,
115 struct device_attribute *attr, char *buf)
116{
117 unsigned int i, c, l, s;
118 struct ipack_device *idev = to_ipack_dev(dev);
119
120
121 switch (idev->id_format) {
122 case IPACK_ID_VERSION_1:
123 l = 0x7; s = 1; break;
124 case IPACK_ID_VERSION_2:
125 l = 0xf; s = 2; break;
126 default:
127 return -EIO;
128 }
129 c = 0;
130 for (i = 0; i < idev->id_avail; i++) {
131 if (i > 0) {
132 if ((i & l) == 0)
133 buf[c++] = '\n';
134 else if ((i & s) == 0)
135 buf[c++] = ' ';
136 }
137 sprintf(&buf[c], "%02x", idev->id[i]);
138 c += 2;
139 }
140 buf[c++] = '\n';
141 return c;
142}
143
144static ssize_t
145id_vendor_show(struct device *dev, struct device_attribute *attr, char *buf)
146{
147 struct ipack_device *idev = to_ipack_dev(dev);
148 switch (idev->id_format) {
149 case IPACK_ID_VERSION_1:
150 return sprintf(buf, "0x%02x\n", idev->id_vendor);
151 case IPACK_ID_VERSION_2:
152 return sprintf(buf, "0x%06x\n", idev->id_vendor);
153 default:
154 return -EIO;
155 }
156}
157
158static ssize_t
159id_device_show(struct device *dev, struct device_attribute *attr, char *buf)
160{
161 struct ipack_device *idev = to_ipack_dev(dev);
162 switch (idev->id_format) {
163 case IPACK_ID_VERSION_1:
164 return sprintf(buf, "0x%02x\n", idev->id_device);
165 case IPACK_ID_VERSION_2:
166 return sprintf(buf, "0x%04x\n", idev->id_device);
167 default:
168 return -EIO;
169 }
170}
171
172static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
173 char *buf)
174{
175 struct ipack_device *idev = to_ipack_dev(dev);
176
177 return sprintf(buf, "ipac:f%02Xv%08Xd%08X", idev->id_format,
178 idev->id_vendor, idev->id_device);
179}
180
181ipack_device_attr(id_format, "0x%hhx\n");
182
183static DEVICE_ATTR_RO(id);
184static DEVICE_ATTR_RO(id_device);
185static DEVICE_ATTR_RO(id_format);
186static DEVICE_ATTR_RO(id_vendor);
187static DEVICE_ATTR_RO(modalias);
188
189static struct attribute *ipack_attrs[] = {
190 &dev_attr_id.attr,
191 &dev_attr_id_device.attr,
192 &dev_attr_id_format.attr,
193 &dev_attr_id_vendor.attr,
194 &dev_attr_modalias.attr,
195 NULL,
196};
197ATTRIBUTE_GROUPS(ipack);
198
199static struct bus_type ipack_bus_type = {
200 .name = "ipack",
201 .probe = ipack_bus_probe,
202 .match = ipack_bus_match,
203 .remove = ipack_bus_remove,
204 .dev_groups = ipack_groups,
205 .uevent = ipack_uevent,
206};
207
208struct ipack_bus_device *ipack_bus_register(struct device *parent, int slots,
209 const struct ipack_bus_ops *ops,
210 struct module *owner)
211{
212 int bus_nr;
213 struct ipack_bus_device *bus;
214
215 bus = kzalloc(sizeof(*bus), GFP_KERNEL);
216 if (!bus)
217 return NULL;
218
219 bus_nr = ida_simple_get(&ipack_ida, 0, 0, GFP_KERNEL);
220 if (bus_nr < 0) {
221 kfree(bus);
222 return NULL;
223 }
224
225 bus->bus_nr = bus_nr;
226 bus->parent = parent;
227 bus->slots = slots;
228 bus->ops = ops;
229 bus->owner = owner;
230 return bus;
231}
232EXPORT_SYMBOL_GPL(ipack_bus_register);
233
234static int ipack_unregister_bus_member(struct device *dev, void *data)
235{
236 struct ipack_device *idev = to_ipack_dev(dev);
237 struct ipack_bus_device *bus = data;
238
239 if (idev->bus == bus)
240 ipack_device_del(idev);
241
242 return 1;
243}
244
245int ipack_bus_unregister(struct ipack_bus_device *bus)
246{
247 bus_for_each_dev(&ipack_bus_type, NULL, bus,
248 ipack_unregister_bus_member);
249 ida_simple_remove(&ipack_ida, bus->bus_nr);
250 kfree(bus);
251 return 0;
252}
253EXPORT_SYMBOL_GPL(ipack_bus_unregister);
254
255int ipack_driver_register(struct ipack_driver *edrv, struct module *owner,
256 const char *name)
257{
258 edrv->driver.owner = owner;
259 edrv->driver.name = name;
260 edrv->driver.bus = &ipack_bus_type;
261 return driver_register(&edrv->driver);
262}
263EXPORT_SYMBOL_GPL(ipack_driver_register);
264
265void ipack_driver_unregister(struct ipack_driver *edrv)
266{
267 driver_unregister(&edrv->driver);
268}
269EXPORT_SYMBOL_GPL(ipack_driver_unregister);
270
271static u16 ipack_crc_byte(u16 crc, u8 c)
272{
273 int i;
274
275 crc ^= c << 8;
276 for (i = 0; i < 8; i++)
277 crc = (crc << 1) ^ ((crc & 0x8000) ? 0x1021 : 0);
278 return crc;
279}
280
281/*
282 * The algorithm in lib/crc-ccitt.c does not seem to apply since it uses the
283 * opposite bit ordering.
284 */
285static u8 ipack_calc_crc1(struct ipack_device *dev)
286{
287 u8 c;
288 u16 crc;
289 unsigned int i;
290
291 crc = 0xffff;
292 for (i = 0; i < dev->id_avail; i++) {
293 c = (i != 11) ? dev->id[i] : 0;
294 crc = ipack_crc_byte(crc, c);
295 }
296 crc = ~crc;
297 return crc & 0xff;
298}
299
300static u16 ipack_calc_crc2(struct ipack_device *dev)
301{
302 u8 c;
303 u16 crc;
304 unsigned int i;
305
306 crc = 0xffff;
307 for (i = 0; i < dev->id_avail; i++) {
308 c = ((i != 0x18) && (i != 0x19)) ? dev->id[i] : 0;
309 crc = ipack_crc_byte(crc, c);
310 }
311 crc = ~crc;
312 return crc;
313}
314
315static void ipack_parse_id1(struct ipack_device *dev)
316{
317 u8 *id = dev->id;
318 u8 crc;
319
320 dev->id_vendor = id[4];
321 dev->id_device = id[5];
322 dev->speed_8mhz = 1;
323 dev->speed_32mhz = (id[7] == 'H');
324 crc = ipack_calc_crc1(dev);
325 dev->id_crc_correct = (crc == id[11]);
326 if (!dev->id_crc_correct) {
327 dev_warn(&dev->dev, "ID CRC invalid found 0x%x, expected 0x%x.\n",
328 id[11], crc);
329 }
330}
331
332static void ipack_parse_id2(struct ipack_device *dev)
333{
334 __be16 *id = (__be16 *) dev->id;
335 u16 flags, crc;
336
337 dev->id_vendor = ((be16_to_cpu(id[3]) & 0xff) << 16)
338 + be16_to_cpu(id[4]);
339 dev->id_device = be16_to_cpu(id[5]);
340 flags = be16_to_cpu(id[10]);
341 dev->speed_8mhz = !!(flags & 2);
342 dev->speed_32mhz = !!(flags & 4);
343 crc = ipack_calc_crc2(dev);
344 dev->id_crc_correct = (crc == be16_to_cpu(id[12]));
345 if (!dev->id_crc_correct) {
346 dev_warn(&dev->dev, "ID CRC invalid found 0x%x, expected 0x%x.\n",
347 id[11], crc);
348 }
349}
350
351static int ipack_device_read_id(struct ipack_device *dev)
352{
353 u8 __iomem *idmem;
354 int i;
355 int ret = 0;
356
357 idmem = ioremap(dev->region[IPACK_ID_SPACE].start,
358 dev->region[IPACK_ID_SPACE].size);
359 if (!idmem) {
360 dev_err(&dev->dev, "error mapping memory\n");
361 return -ENOMEM;
362 }
363
364 /* Determine ID PROM Data Format. If we find the ids "IPAC" or "IPAH"
365 * we are dealing with a IndustryPack format 1 device. If we detect
366 * "VITA4 " (16 bit big endian formatted) we are dealing with a
367 * IndustryPack format 2 device */
368 if ((ioread8(idmem + 1) == 'I') &&
369 (ioread8(idmem + 3) == 'P') &&
370 (ioread8(idmem + 5) == 'A') &&
371 ((ioread8(idmem + 7) == 'C') ||
372 (ioread8(idmem + 7) == 'H'))) {
373 dev->id_format = IPACK_ID_VERSION_1;
374 dev->id_avail = ioread8(idmem + 0x15);
375 if ((dev->id_avail < 0x0c) || (dev->id_avail > 0x40)) {
376 dev_warn(&dev->dev, "invalid id size");
377 dev->id_avail = 0x0c;
378 }
379 } else if ((ioread8(idmem + 0) == 'I') &&
380 (ioread8(idmem + 1) == 'V') &&
381 (ioread8(idmem + 2) == 'A') &&
382 (ioread8(idmem + 3) == 'T') &&
383 (ioread8(idmem + 4) == ' ') &&
384 (ioread8(idmem + 5) == '4')) {
385 dev->id_format = IPACK_ID_VERSION_2;
386 dev->id_avail = ioread16be(idmem + 0x16);
387 if ((dev->id_avail < 0x1a) || (dev->id_avail > 0x40)) {
388 dev_warn(&dev->dev, "invalid id size");
389 dev->id_avail = 0x1a;
390 }
391 } else {
392 dev->id_format = IPACK_ID_VERSION_INVALID;
393 dev->id_avail = 0;
394 }
395
396 if (!dev->id_avail) {
397 ret = -ENODEV;
398 goto out;
399 }
400
401 /* Obtain the amount of memory required to store a copy of the complete
402 * ID ROM contents */
403 dev->id = kmalloc(dev->id_avail, GFP_KERNEL);
404 if (!dev->id) {
405 ret = -ENOMEM;
406 goto out;
407 }
408 for (i = 0; i < dev->id_avail; i++) {
409 if (dev->id_format == IPACK_ID_VERSION_1)
410 dev->id[i] = ioread8(idmem + (i << 1) + 1);
411 else
412 dev->id[i] = ioread8(idmem + i);
413 }
414
415 /* now we can finally work with the copy */
416 switch (dev->id_format) {
417 case IPACK_ID_VERSION_1:
418 ipack_parse_id1(dev);
419 break;
420 case IPACK_ID_VERSION_2:
421 ipack_parse_id2(dev);
422 break;
423 }
424
425out:
426 iounmap(idmem);
427
428 return ret;
429}
430
431int ipack_device_init(struct ipack_device *dev)
432{
433 int ret;
434
435 dev->dev.bus = &ipack_bus_type;
436 dev->dev.release = ipack_device_release;
437 dev->dev.parent = dev->bus->parent;
438 dev_set_name(&dev->dev,
439 "ipack-dev.%u.%u", dev->bus->bus_nr, dev->slot);
440 device_initialize(&dev->dev);
441
442 if (dev->bus->ops->set_clockrate(dev, 8))
443 dev_warn(&dev->dev, "failed to switch to 8 MHz operation for reading of device ID.\n");
444 if (dev->bus->ops->reset_timeout(dev))
445 dev_warn(&dev->dev, "failed to reset potential timeout.");
446
447 ret = ipack_device_read_id(dev);
448 if (ret < 0) {
449 dev_err(&dev->dev, "error reading device id section.\n");
450 return ret;
451 }
452
453 /* if the device supports 32 MHz operation, use it. */
454 if (dev->speed_32mhz) {
455 ret = dev->bus->ops->set_clockrate(dev, 32);
456 if (ret < 0)
457 dev_err(&dev->dev, "failed to switch to 32 MHz operation.\n");
458 }
459
460 return 0;
461}
462EXPORT_SYMBOL_GPL(ipack_device_init);
463
464int ipack_device_add(struct ipack_device *dev)
465{
466 return device_add(&dev->dev);
467}
468EXPORT_SYMBOL_GPL(ipack_device_add);
469
470void ipack_device_del(struct ipack_device *dev)
471{
472 device_del(&dev->dev);
473 ipack_put_device(dev);
474}
475EXPORT_SYMBOL_GPL(ipack_device_del);
476
477void ipack_get_device(struct ipack_device *dev)
478{
479 get_device(&dev->dev);
480}
481EXPORT_SYMBOL_GPL(ipack_get_device);
482
483void ipack_put_device(struct ipack_device *dev)
484{
485 put_device(&dev->dev);
486}
487EXPORT_SYMBOL_GPL(ipack_put_device);
488
489static int __init ipack_init(void)
490{
491 ida_init(&ipack_ida);
492 return bus_register(&ipack_bus_type);
493}
494
495static void __exit ipack_exit(void)
496{
497 bus_unregister(&ipack_bus_type);
498 ida_destroy(&ipack_ida);
499}
500
501module_init(ipack_init);
502module_exit(ipack_exit);
503
504MODULE_AUTHOR("Samuel Iglesias Gonsalvez <siglesias@igalia.com>");
505MODULE_LICENSE("GPL");
506MODULE_DESCRIPTION("Industry-pack bus core");
507