Linux 5.15-rc6
[muen/linux.git] / drivers / ipack / ipack.c
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(struct device *dev, struct kobj_uevent_env *env)
80 {
81         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         dev_set_name(&dev->dev,
433                      "ipack-dev.%u.%u", dev->bus->bus_nr, dev->slot);
434         device_initialize(&dev->dev);
435
436         if (dev->bus->ops->set_clockrate(dev, 8))
437                 dev_warn(&dev->dev, "failed to switch to 8 MHz operation for reading of device ID.\n");
438         if (dev->bus->ops->reset_timeout(dev))
439                 dev_warn(&dev->dev, "failed to reset potential timeout.");
440
441         ret = ipack_device_read_id(dev);
442         if (ret < 0) {
443                 dev_err(&dev->dev, "error reading device id section.\n");
444                 return ret;
445         }
446
447         /* if the device supports 32 MHz operation, use it. */
448         if (dev->speed_32mhz) {
449                 ret = dev->bus->ops->set_clockrate(dev, 32);
450                 if (ret < 0)
451                         dev_err(&dev->dev, "failed to switch to 32 MHz operation.\n");
452         }
453
454         return 0;
455 }
456 EXPORT_SYMBOL_GPL(ipack_device_init);
457
458 int ipack_device_add(struct ipack_device *dev)
459 {
460         return device_add(&dev->dev);
461 }
462 EXPORT_SYMBOL_GPL(ipack_device_add);
463
464 void ipack_device_del(struct ipack_device *dev)
465 {
466         device_del(&dev->dev);
467         ipack_put_device(dev);
468 }
469 EXPORT_SYMBOL_GPL(ipack_device_del);
470
471 void ipack_get_device(struct ipack_device *dev)
472 {
473         get_device(&dev->dev);
474 }
475 EXPORT_SYMBOL_GPL(ipack_get_device);
476
477 void ipack_put_device(struct ipack_device *dev)
478 {
479         put_device(&dev->dev);
480 }
481 EXPORT_SYMBOL_GPL(ipack_put_device);
482
483 static int __init ipack_init(void)
484 {
485         ida_init(&ipack_ida);
486         return bus_register(&ipack_bus_type);
487 }
488
489 static void __exit ipack_exit(void)
490 {
491         bus_unregister(&ipack_bus_type);
492         ida_destroy(&ipack_ida);
493 }
494
495 module_init(ipack_init);
496 module_exit(ipack_exit);
497
498 MODULE_AUTHOR("Samuel Iglesias Gonsalvez <siglesias@igalia.com>");
499 MODULE_LICENSE("GPL");
500 MODULE_DESCRIPTION("Industry-pack bus core");