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(objp: 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(id: ids, device: 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(ids: 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 | format: "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: &buf[c], fmt: "%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, fmt: "0x%02x\n" , idev->id_vendor); |
142 | case IPACK_ID_VERSION_2: |
143 | return sprintf(buf, fmt: "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, fmt: "0x%02x\n" , idev->id_device); |
156 | case IPACK_ID_VERSION_2: |
157 | return sprintf(buf, fmt: "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, fmt: "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 | |
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(size: sizeof(*bus), GFP_KERNEL); |
207 | if (!bus) |
208 | return NULL; |
209 | |
210 | bus_nr = ida_alloc(ida: &ipack_ida, GFP_KERNEL); |
211 | if (bus_nr < 0) { |
212 | kfree(objp: 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(dev: idev); |
232 | |
233 | return 1; |
234 | } |
235 | |
236 | int ipack_bus_unregister(struct ipack_bus_device *bus) |
237 | { |
238 | bus_for_each_dev(bus: &ipack_bus_type, NULL, data: bus, |
239 | fn: ipack_unregister_bus_member); |
240 | ida_free(&ipack_ida, id: bus->bus_nr); |
241 | kfree(objp: 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(drv: &edrv->driver); |
256 | } |
257 | EXPORT_SYMBOL_GPL(ipack_driver_register); |
258 | |
259 | void ipack_driver_unregister(struct ipack_driver *edrv) |
260 | { |
261 | driver_unregister(drv: &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(offset: dev->region[IPACK_ID_SPACE].start, |
352 | size: 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(size: 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(addr: 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->dev, |
433 | name: "ipack-dev.%u.%u" , dev->bus->bus_nr, dev->slot); |
434 | if (ret) |
435 | return ret; |
436 | |
437 | device_initialize(dev: &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->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->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->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->dev); |
483 | } |
484 | EXPORT_SYMBOL_GPL(ipack_put_device); |
485 | |
486 | static int __init ipack_init(void) |
487 | { |
488 | ida_init(ida: &ipack_ida); |
489 | return bus_register(bus: &ipack_bus_type); |
490 | } |
491 | |
492 | static void __exit ipack_exit(void) |
493 | { |
494 | bus_unregister(bus: &ipack_bus_type); |
495 | ida_destroy(ida: &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 | |