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b1c1db98 | 1 | // SPDX-License-Identifier: GPL-2.0 |
eace75cf SK |
2 | /* |
3 | * nvmem framework core. | |
4 | * | |
5 | * Copyright (C) 2015 Srinivas Kandagatla <srinivas.kandagatla@linaro.org> | |
6 | * Copyright (C) 2013 Maxime Ripard <maxime.ripard@free-electrons.com> | |
eace75cf SK |
7 | */ |
8 | ||
9 | #include <linux/device.h> | |
10 | #include <linux/export.h> | |
11 | #include <linux/fs.h> | |
12 | #include <linux/idr.h> | |
13 | #include <linux/init.h> | |
c1de7f43 | 14 | #include <linux/kref.h> |
eace75cf SK |
15 | #include <linux/module.h> |
16 | #include <linux/nvmem-consumer.h> | |
17 | #include <linux/nvmem-provider.h> | |
18 | #include <linux/of.h> | |
eace75cf SK |
19 | #include <linux/slab.h> |
20 | ||
21 | struct nvmem_device { | |
eace75cf SK |
22 | struct module *owner; |
23 | struct device dev; | |
24 | int stride; | |
25 | int word_size; | |
eace75cf | 26 | int id; |
c1de7f43 | 27 | struct kref refcnt; |
eace75cf SK |
28 | size_t size; |
29 | bool read_only; | |
b6c217ab AL |
30 | int flags; |
31 | struct bin_attribute eeprom; | |
32 | struct device *base_dev; | |
c7235ee3 | 33 | struct list_head cells; |
795ddd18 SK |
34 | nvmem_reg_read_t reg_read; |
35 | nvmem_reg_write_t reg_write; | |
36 | void *priv; | |
eace75cf SK |
37 | }; |
38 | ||
b6c217ab AL |
39 | #define FLAG_COMPAT BIT(0) |
40 | ||
eace75cf SK |
41 | struct nvmem_cell { |
42 | const char *name; | |
43 | int offset; | |
44 | int bytes; | |
45 | int bit_offset; | |
46 | int nbits; | |
47 | struct nvmem_device *nvmem; | |
48 | struct list_head node; | |
49 | }; | |
50 | ||
51 | static DEFINE_MUTEX(nvmem_mutex); | |
52 | static DEFINE_IDA(nvmem_ida); | |
53 | ||
b985f4cb BG |
54 | static DEFINE_MUTEX(nvmem_cell_mutex); |
55 | static LIST_HEAD(nvmem_cell_tables); | |
56 | ||
506157be BG |
57 | static DEFINE_MUTEX(nvmem_lookup_mutex); |
58 | static LIST_HEAD(nvmem_lookup_list); | |
59 | ||
bee1138b BG |
60 | static BLOCKING_NOTIFIER_HEAD(nvmem_notifier); |
61 | ||
b6c217ab AL |
62 | #ifdef CONFIG_DEBUG_LOCK_ALLOC |
63 | static struct lock_class_key eeprom_lock_key; | |
64 | #endif | |
65 | ||
eace75cf | 66 | #define to_nvmem_device(d) container_of(d, struct nvmem_device, dev) |
795ddd18 SK |
67 | static int nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset, |
68 | void *val, size_t bytes) | |
69 | { | |
70 | if (nvmem->reg_read) | |
71 | return nvmem->reg_read(nvmem->priv, offset, val, bytes); | |
72 | ||
73 | return -EINVAL; | |
74 | } | |
75 | ||
76 | static int nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset, | |
77 | void *val, size_t bytes) | |
78 | { | |
79 | if (nvmem->reg_write) | |
80 | return nvmem->reg_write(nvmem->priv, offset, val, bytes); | |
81 | ||
82 | return -EINVAL; | |
83 | } | |
eace75cf SK |
84 | |
85 | static ssize_t bin_attr_nvmem_read(struct file *filp, struct kobject *kobj, | |
86 | struct bin_attribute *attr, | |
87 | char *buf, loff_t pos, size_t count) | |
88 | { | |
b6c217ab AL |
89 | struct device *dev; |
90 | struct nvmem_device *nvmem; | |
eace75cf SK |
91 | int rc; |
92 | ||
b6c217ab AL |
93 | if (attr->private) |
94 | dev = attr->private; | |
95 | else | |
96 | dev = container_of(kobj, struct device, kobj); | |
97 | nvmem = to_nvmem_device(dev); | |
98 | ||
eace75cf | 99 | /* Stop the user from reading */ |
7c806883 | 100 | if (pos >= nvmem->size) |
eace75cf SK |
101 | return 0; |
102 | ||
313a72ff SK |
103 | if (count < nvmem->word_size) |
104 | return -EINVAL; | |
105 | ||
eace75cf SK |
106 | if (pos + count > nvmem->size) |
107 | count = nvmem->size - pos; | |
108 | ||
109 | count = round_down(count, nvmem->word_size); | |
110 | ||
795ddd18 | 111 | rc = nvmem_reg_read(nvmem, pos, buf, count); |
eace75cf | 112 | |
287980e4 | 113 | if (rc) |
eace75cf SK |
114 | return rc; |
115 | ||
116 | return count; | |
117 | } | |
118 | ||
119 | static ssize_t bin_attr_nvmem_write(struct file *filp, struct kobject *kobj, | |
120 | struct bin_attribute *attr, | |
121 | char *buf, loff_t pos, size_t count) | |
122 | { | |
b6c217ab AL |
123 | struct device *dev; |
124 | struct nvmem_device *nvmem; | |
eace75cf SK |
125 | int rc; |
126 | ||
b6c217ab AL |
127 | if (attr->private) |
128 | dev = attr->private; | |
129 | else | |
130 | dev = container_of(kobj, struct device, kobj); | |
131 | nvmem = to_nvmem_device(dev); | |
132 | ||
eace75cf | 133 | /* Stop the user from writing */ |
7c806883 | 134 | if (pos >= nvmem->size) |
38b0774c | 135 | return -EFBIG; |
eace75cf | 136 | |
313a72ff SK |
137 | if (count < nvmem->word_size) |
138 | return -EINVAL; | |
139 | ||
eace75cf SK |
140 | if (pos + count > nvmem->size) |
141 | count = nvmem->size - pos; | |
142 | ||
143 | count = round_down(count, nvmem->word_size); | |
144 | ||
795ddd18 | 145 | rc = nvmem_reg_write(nvmem, pos, buf, count); |
eace75cf | 146 | |
287980e4 | 147 | if (rc) |
eace75cf SK |
148 | return rc; |
149 | ||
150 | return count; | |
151 | } | |
152 | ||
153 | /* default read/write permissions */ | |
154 | static struct bin_attribute bin_attr_rw_nvmem = { | |
155 | .attr = { | |
156 | .name = "nvmem", | |
157 | .mode = S_IWUSR | S_IRUGO, | |
158 | }, | |
159 | .read = bin_attr_nvmem_read, | |
160 | .write = bin_attr_nvmem_write, | |
161 | }; | |
162 | ||
163 | static struct bin_attribute *nvmem_bin_rw_attributes[] = { | |
164 | &bin_attr_rw_nvmem, | |
165 | NULL, | |
166 | }; | |
167 | ||
168 | static const struct attribute_group nvmem_bin_rw_group = { | |
169 | .bin_attrs = nvmem_bin_rw_attributes, | |
170 | }; | |
171 | ||
172 | static const struct attribute_group *nvmem_rw_dev_groups[] = { | |
173 | &nvmem_bin_rw_group, | |
174 | NULL, | |
175 | }; | |
176 | ||
177 | /* read only permission */ | |
178 | static struct bin_attribute bin_attr_ro_nvmem = { | |
179 | .attr = { | |
180 | .name = "nvmem", | |
181 | .mode = S_IRUGO, | |
182 | }, | |
183 | .read = bin_attr_nvmem_read, | |
184 | }; | |
185 | ||
186 | static struct bin_attribute *nvmem_bin_ro_attributes[] = { | |
187 | &bin_attr_ro_nvmem, | |
188 | NULL, | |
189 | }; | |
190 | ||
191 | static const struct attribute_group nvmem_bin_ro_group = { | |
192 | .bin_attrs = nvmem_bin_ro_attributes, | |
193 | }; | |
194 | ||
195 | static const struct attribute_group *nvmem_ro_dev_groups[] = { | |
196 | &nvmem_bin_ro_group, | |
197 | NULL, | |
198 | }; | |
199 | ||
811b0d65 AL |
200 | /* default read/write permissions, root only */ |
201 | static struct bin_attribute bin_attr_rw_root_nvmem = { | |
202 | .attr = { | |
203 | .name = "nvmem", | |
204 | .mode = S_IWUSR | S_IRUSR, | |
205 | }, | |
206 | .read = bin_attr_nvmem_read, | |
207 | .write = bin_attr_nvmem_write, | |
208 | }; | |
209 | ||
210 | static struct bin_attribute *nvmem_bin_rw_root_attributes[] = { | |
211 | &bin_attr_rw_root_nvmem, | |
212 | NULL, | |
213 | }; | |
214 | ||
215 | static const struct attribute_group nvmem_bin_rw_root_group = { | |
216 | .bin_attrs = nvmem_bin_rw_root_attributes, | |
217 | }; | |
218 | ||
219 | static const struct attribute_group *nvmem_rw_root_dev_groups[] = { | |
220 | &nvmem_bin_rw_root_group, | |
221 | NULL, | |
222 | }; | |
223 | ||
224 | /* read only permission, root only */ | |
225 | static struct bin_attribute bin_attr_ro_root_nvmem = { | |
226 | .attr = { | |
227 | .name = "nvmem", | |
228 | .mode = S_IRUSR, | |
229 | }, | |
230 | .read = bin_attr_nvmem_read, | |
231 | }; | |
232 | ||
233 | static struct bin_attribute *nvmem_bin_ro_root_attributes[] = { | |
234 | &bin_attr_ro_root_nvmem, | |
235 | NULL, | |
236 | }; | |
237 | ||
238 | static const struct attribute_group nvmem_bin_ro_root_group = { | |
239 | .bin_attrs = nvmem_bin_ro_root_attributes, | |
240 | }; | |
241 | ||
242 | static const struct attribute_group *nvmem_ro_root_dev_groups[] = { | |
243 | &nvmem_bin_ro_root_group, | |
244 | NULL, | |
245 | }; | |
246 | ||
eace75cf SK |
247 | static void nvmem_release(struct device *dev) |
248 | { | |
249 | struct nvmem_device *nvmem = to_nvmem_device(dev); | |
250 | ||
251 | ida_simple_remove(&nvmem_ida, nvmem->id); | |
252 | kfree(nvmem); | |
253 | } | |
254 | ||
255 | static const struct device_type nvmem_provider_type = { | |
256 | .release = nvmem_release, | |
257 | }; | |
258 | ||
259 | static struct bus_type nvmem_bus_type = { | |
260 | .name = "nvmem", | |
261 | }; | |
262 | ||
263 | static int of_nvmem_match(struct device *dev, void *nvmem_np) | |
264 | { | |
265 | return dev->of_node == nvmem_np; | |
266 | } | |
267 | ||
268 | static struct nvmem_device *of_nvmem_find(struct device_node *nvmem_np) | |
269 | { | |
270 | struct device *d; | |
271 | ||
272 | if (!nvmem_np) | |
273 | return NULL; | |
274 | ||
275 | d = bus_find_device(&nvmem_bus_type, NULL, nvmem_np, of_nvmem_match); | |
276 | ||
277 | if (!d) | |
278 | return NULL; | |
279 | ||
280 | return to_nvmem_device(d); | |
281 | } | |
282 | ||
506157be BG |
283 | static struct nvmem_device *nvmem_find(const char *name) |
284 | { | |
285 | struct device *d; | |
286 | ||
287 | d = bus_find_device_by_name(&nvmem_bus_type, NULL, name); | |
288 | ||
289 | if (!d) | |
290 | return NULL; | |
291 | ||
292 | return to_nvmem_device(d); | |
293 | } | |
294 | ||
eace75cf SK |
295 | static void nvmem_cell_drop(struct nvmem_cell *cell) |
296 | { | |
bee1138b | 297 | blocking_notifier_call_chain(&nvmem_notifier, NVMEM_CELL_REMOVE, cell); |
c7235ee3 | 298 | mutex_lock(&nvmem_mutex); |
eace75cf | 299 | list_del(&cell->node); |
c7235ee3 | 300 | mutex_unlock(&nvmem_mutex); |
eace75cf SK |
301 | kfree(cell); |
302 | } | |
303 | ||
304 | static void nvmem_device_remove_all_cells(const struct nvmem_device *nvmem) | |
305 | { | |
1852183e | 306 | struct nvmem_cell *cell, *p; |
eace75cf | 307 | |
c7235ee3 BG |
308 | list_for_each_entry_safe(cell, p, &nvmem->cells, node) |
309 | nvmem_cell_drop(cell); | |
eace75cf SK |
310 | } |
311 | ||
312 | static void nvmem_cell_add(struct nvmem_cell *cell) | |
313 | { | |
c7235ee3 BG |
314 | mutex_lock(&nvmem_mutex); |
315 | list_add_tail(&cell->node, &cell->nvmem->cells); | |
316 | mutex_unlock(&nvmem_mutex); | |
bee1138b | 317 | blocking_notifier_call_chain(&nvmem_notifier, NVMEM_CELL_ADD, cell); |
eace75cf SK |
318 | } |
319 | ||
320 | static int nvmem_cell_info_to_nvmem_cell(struct nvmem_device *nvmem, | |
321 | const struct nvmem_cell_info *info, | |
322 | struct nvmem_cell *cell) | |
323 | { | |
324 | cell->nvmem = nvmem; | |
325 | cell->offset = info->offset; | |
326 | cell->bytes = info->bytes; | |
327 | cell->name = info->name; | |
328 | ||
329 | cell->bit_offset = info->bit_offset; | |
330 | cell->nbits = info->nbits; | |
331 | ||
332 | if (cell->nbits) | |
333 | cell->bytes = DIV_ROUND_UP(cell->nbits + cell->bit_offset, | |
334 | BITS_PER_BYTE); | |
335 | ||
336 | if (!IS_ALIGNED(cell->offset, nvmem->stride)) { | |
337 | dev_err(&nvmem->dev, | |
338 | "cell %s unaligned to nvmem stride %d\n", | |
339 | cell->name, nvmem->stride); | |
340 | return -EINVAL; | |
341 | } | |
342 | ||
343 | return 0; | |
344 | } | |
345 | ||
b3db17e4 AL |
346 | /** |
347 | * nvmem_add_cells() - Add cell information to an nvmem device | |
348 | * | |
349 | * @nvmem: nvmem device to add cells to. | |
350 | * @info: nvmem cell info to add to the device | |
351 | * @ncells: number of cells in info | |
352 | * | |
353 | * Return: 0 or negative error code on failure. | |
354 | */ | |
355 | int nvmem_add_cells(struct nvmem_device *nvmem, | |
356 | const struct nvmem_cell_info *info, | |
357 | int ncells) | |
eace75cf SK |
358 | { |
359 | struct nvmem_cell **cells; | |
eace75cf SK |
360 | int i, rval; |
361 | ||
b3db17e4 | 362 | cells = kcalloc(ncells, sizeof(*cells), GFP_KERNEL); |
eace75cf SK |
363 | if (!cells) |
364 | return -ENOMEM; | |
365 | ||
b3db17e4 | 366 | for (i = 0; i < ncells; i++) { |
eace75cf SK |
367 | cells[i] = kzalloc(sizeof(**cells), GFP_KERNEL); |
368 | if (!cells[i]) { | |
369 | rval = -ENOMEM; | |
370 | goto err; | |
371 | } | |
372 | ||
373 | rval = nvmem_cell_info_to_nvmem_cell(nvmem, &info[i], cells[i]); | |
287980e4 | 374 | if (rval) { |
eace75cf SK |
375 | kfree(cells[i]); |
376 | goto err; | |
377 | } | |
378 | ||
379 | nvmem_cell_add(cells[i]); | |
380 | } | |
381 | ||
eace75cf SK |
382 | /* remove tmp array */ |
383 | kfree(cells); | |
384 | ||
385 | return 0; | |
386 | err: | |
dfdf1414 | 387 | while (i--) |
eace75cf SK |
388 | nvmem_cell_drop(cells[i]); |
389 | ||
dfdf1414 RV |
390 | kfree(cells); |
391 | ||
eace75cf SK |
392 | return rval; |
393 | } | |
b3db17e4 | 394 | EXPORT_SYMBOL_GPL(nvmem_add_cells); |
eace75cf | 395 | |
b6c217ab AL |
396 | /* |
397 | * nvmem_setup_compat() - Create an additional binary entry in | |
398 | * drivers sys directory, to be backwards compatible with the older | |
399 | * drivers/misc/eeprom drivers. | |
400 | */ | |
401 | static int nvmem_setup_compat(struct nvmem_device *nvmem, | |
402 | const struct nvmem_config *config) | |
403 | { | |
404 | int rval; | |
405 | ||
406 | if (!config->base_dev) | |
407 | return -EINVAL; | |
408 | ||
409 | if (nvmem->read_only) | |
410 | nvmem->eeprom = bin_attr_ro_root_nvmem; | |
411 | else | |
412 | nvmem->eeprom = bin_attr_rw_root_nvmem; | |
413 | nvmem->eeprom.attr.name = "eeprom"; | |
414 | nvmem->eeprom.size = nvmem->size; | |
415 | #ifdef CONFIG_DEBUG_LOCK_ALLOC | |
416 | nvmem->eeprom.attr.key = &eeprom_lock_key; | |
417 | #endif | |
418 | nvmem->eeprom.private = &nvmem->dev; | |
419 | nvmem->base_dev = config->base_dev; | |
420 | ||
421 | rval = device_create_bin_file(nvmem->base_dev, &nvmem->eeprom); | |
422 | if (rval) { | |
423 | dev_err(&nvmem->dev, | |
424 | "Failed to create eeprom binary file %d\n", rval); | |
425 | return rval; | |
426 | } | |
427 | ||
428 | nvmem->flags |= FLAG_COMPAT; | |
429 | ||
430 | return 0; | |
431 | } | |
432 | ||
bee1138b BG |
433 | /** |
434 | * nvmem_register_notifier() - Register a notifier block for nvmem events. | |
435 | * | |
436 | * @nb: notifier block to be called on nvmem events. | |
437 | * | |
438 | * Return: 0 on success, negative error number on failure. | |
439 | */ | |
440 | int nvmem_register_notifier(struct notifier_block *nb) | |
441 | { | |
442 | return blocking_notifier_chain_register(&nvmem_notifier, nb); | |
443 | } | |
444 | EXPORT_SYMBOL_GPL(nvmem_register_notifier); | |
445 | ||
446 | /** | |
447 | * nvmem_unregister_notifier() - Unregister a notifier block for nvmem events. | |
448 | * | |
449 | * @nb: notifier block to be unregistered. | |
450 | * | |
451 | * Return: 0 on success, negative error number on failure. | |
452 | */ | |
453 | int nvmem_unregister_notifier(struct notifier_block *nb) | |
454 | { | |
455 | return blocking_notifier_chain_unregister(&nvmem_notifier, nb); | |
456 | } | |
457 | EXPORT_SYMBOL_GPL(nvmem_unregister_notifier); | |
458 | ||
b985f4cb BG |
459 | static int nvmem_add_cells_from_table(struct nvmem_device *nvmem) |
460 | { | |
461 | const struct nvmem_cell_info *info; | |
462 | struct nvmem_cell_table *table; | |
463 | struct nvmem_cell *cell; | |
464 | int rval = 0, i; | |
465 | ||
466 | mutex_lock(&nvmem_cell_mutex); | |
467 | list_for_each_entry(table, &nvmem_cell_tables, node) { | |
468 | if (strcmp(nvmem_dev_name(nvmem), table->nvmem_name) == 0) { | |
469 | for (i = 0; i < table->ncells; i++) { | |
470 | info = &table->cells[i]; | |
471 | ||
472 | cell = kzalloc(sizeof(*cell), GFP_KERNEL); | |
473 | if (!cell) { | |
474 | rval = -ENOMEM; | |
475 | goto out; | |
476 | } | |
477 | ||
478 | rval = nvmem_cell_info_to_nvmem_cell(nvmem, | |
479 | info, | |
480 | cell); | |
481 | if (rval) { | |
482 | kfree(cell); | |
483 | goto out; | |
484 | } | |
485 | ||
486 | nvmem_cell_add(cell); | |
487 | } | |
488 | } | |
489 | } | |
490 | ||
491 | out: | |
492 | mutex_unlock(&nvmem_cell_mutex); | |
493 | return rval; | |
494 | } | |
495 | ||
e888d445 BG |
496 | static struct nvmem_cell * |
497 | nvmem_find_cell_by_index(struct nvmem_device *nvmem, int index) | |
498 | { | |
499 | struct nvmem_cell *cell = NULL; | |
500 | int i = 0; | |
501 | ||
502 | mutex_lock(&nvmem_mutex); | |
503 | list_for_each_entry(cell, &nvmem->cells, node) { | |
504 | if (index == i++) | |
505 | break; | |
506 | } | |
507 | mutex_unlock(&nvmem_mutex); | |
508 | ||
509 | return cell; | |
510 | } | |
511 | ||
506157be BG |
512 | static struct nvmem_cell * |
513 | nvmem_find_cell_by_name(struct nvmem_device *nvmem, const char *cell_id) | |
514 | { | |
515 | struct nvmem_cell *cell = NULL; | |
516 | ||
517 | mutex_lock(&nvmem_mutex); | |
518 | list_for_each_entry(cell, &nvmem->cells, node) { | |
519 | if (strcmp(cell_id, cell->name) == 0) | |
520 | break; | |
521 | } | |
522 | mutex_unlock(&nvmem_mutex); | |
523 | ||
524 | return cell; | |
525 | } | |
526 | ||
e888d445 BG |
527 | static int nvmem_add_cells_from_of(struct nvmem_device *nvmem) |
528 | { | |
529 | struct device_node *parent, *child; | |
530 | struct device *dev = &nvmem->dev; | |
531 | struct nvmem_cell *cell; | |
532 | const __be32 *addr; | |
533 | int len; | |
534 | ||
535 | parent = dev->of_node; | |
536 | ||
537 | for_each_child_of_node(parent, child) { | |
538 | addr = of_get_property(child, "reg", &len); | |
539 | if (!addr || (len < 2 * sizeof(u32))) { | |
540 | dev_err(dev, "nvmem: invalid reg on %pOF\n", child); | |
541 | return -EINVAL; | |
542 | } | |
543 | ||
544 | cell = kzalloc(sizeof(*cell), GFP_KERNEL); | |
545 | if (!cell) | |
546 | return -ENOMEM; | |
547 | ||
548 | cell->nvmem = nvmem; | |
549 | cell->offset = be32_to_cpup(addr++); | |
550 | cell->bytes = be32_to_cpup(addr); | |
551 | cell->name = child->name; | |
552 | ||
553 | addr = of_get_property(child, "bits", &len); | |
554 | if (addr && len == (2 * sizeof(u32))) { | |
555 | cell->bit_offset = be32_to_cpup(addr++); | |
556 | cell->nbits = be32_to_cpup(addr); | |
557 | } | |
558 | ||
559 | if (cell->nbits) | |
560 | cell->bytes = DIV_ROUND_UP( | |
561 | cell->nbits + cell->bit_offset, | |
562 | BITS_PER_BYTE); | |
563 | ||
564 | if (!IS_ALIGNED(cell->offset, nvmem->stride)) { | |
565 | dev_err(dev, "cell %s unaligned to nvmem stride %d\n", | |
566 | cell->name, nvmem->stride); | |
567 | /* Cells already added will be freed later. */ | |
568 | kfree(cell); | |
569 | return -EINVAL; | |
570 | } | |
571 | ||
572 | nvmem_cell_add(cell); | |
573 | } | |
574 | ||
575 | return 0; | |
576 | } | |
577 | ||
eace75cf SK |
578 | /** |
579 | * nvmem_register() - Register a nvmem device for given nvmem_config. | |
580 | * Also creates an binary entry in /sys/bus/nvmem/devices/dev-name/nvmem | |
581 | * | |
582 | * @config: nvmem device configuration with which nvmem device is created. | |
583 | * | |
584 | * Return: Will be an ERR_PTR() on error or a valid pointer to nvmem_device | |
585 | * on success. | |
586 | */ | |
587 | ||
588 | struct nvmem_device *nvmem_register(const struct nvmem_config *config) | |
589 | { | |
590 | struct nvmem_device *nvmem; | |
eace75cf SK |
591 | int rval; |
592 | ||
593 | if (!config->dev) | |
594 | return ERR_PTR(-EINVAL); | |
595 | ||
eace75cf SK |
596 | nvmem = kzalloc(sizeof(*nvmem), GFP_KERNEL); |
597 | if (!nvmem) | |
598 | return ERR_PTR(-ENOMEM); | |
599 | ||
600 | rval = ida_simple_get(&nvmem_ida, 0, 0, GFP_KERNEL); | |
601 | if (rval < 0) { | |
602 | kfree(nvmem); | |
603 | return ERR_PTR(rval); | |
604 | } | |
605 | ||
c1de7f43 | 606 | kref_init(&nvmem->refcnt); |
c7235ee3 | 607 | INIT_LIST_HEAD(&nvmem->cells); |
c1de7f43 | 608 | |
eace75cf | 609 | nvmem->id = rval; |
eace75cf | 610 | nvmem->owner = config->owner; |
17eb18d6 MY |
611 | if (!nvmem->owner && config->dev->driver) |
612 | nvmem->owner = config->dev->driver->owner; | |
99897efd HK |
613 | nvmem->stride = config->stride ?: 1; |
614 | nvmem->word_size = config->word_size ?: 1; | |
795ddd18 | 615 | nvmem->size = config->size; |
eace75cf SK |
616 | nvmem->dev.type = &nvmem_provider_type; |
617 | nvmem->dev.bus = &nvmem_bus_type; | |
618 | nvmem->dev.parent = config->dev; | |
795ddd18 SK |
619 | nvmem->priv = config->priv; |
620 | nvmem->reg_read = config->reg_read; | |
621 | nvmem->reg_write = config->reg_write; | |
fc2f9970 | 622 | nvmem->dev.of_node = config->dev->of_node; |
fd0f4906 AS |
623 | |
624 | if (config->id == -1 && config->name) { | |
625 | dev_set_name(&nvmem->dev, "%s", config->name); | |
626 | } else { | |
627 | dev_set_name(&nvmem->dev, "%s%d", | |
628 | config->name ? : "nvmem", | |
629 | config->name ? config->id : nvmem->id); | |
630 | } | |
eace75cf | 631 | |
fc2f9970 | 632 | nvmem->read_only = device_property_present(config->dev, "read-only") | |
eace75cf SK |
633 | config->read_only; |
634 | ||
811b0d65 AL |
635 | if (config->root_only) |
636 | nvmem->dev.groups = nvmem->read_only ? | |
637 | nvmem_ro_root_dev_groups : | |
638 | nvmem_rw_root_dev_groups; | |
639 | else | |
640 | nvmem->dev.groups = nvmem->read_only ? | |
641 | nvmem_ro_dev_groups : | |
642 | nvmem_rw_dev_groups; | |
eace75cf SK |
643 | |
644 | device_initialize(&nvmem->dev); | |
645 | ||
646 | dev_dbg(&nvmem->dev, "Registering nvmem device %s\n", config->name); | |
647 | ||
648 | rval = device_add(&nvmem->dev); | |
b6c217ab | 649 | if (rval) |
3360acdf | 650 | goto err_put_device; |
b6c217ab AL |
651 | |
652 | if (config->compat) { | |
653 | rval = nvmem_setup_compat(nvmem, config); | |
654 | if (rval) | |
3360acdf | 655 | goto err_device_del; |
eace75cf SK |
656 | } |
657 | ||
fa72d847 BG |
658 | if (config->cells) { |
659 | rval = nvmem_add_cells(nvmem, config->cells, config->ncells); | |
660 | if (rval) | |
661 | goto err_teardown_compat; | |
662 | } | |
eace75cf | 663 | |
b985f4cb BG |
664 | rval = nvmem_add_cells_from_table(nvmem); |
665 | if (rval) | |
666 | goto err_remove_cells; | |
667 | ||
e888d445 BG |
668 | rval = nvmem_add_cells_from_of(nvmem); |
669 | if (rval) | |
670 | goto err_remove_cells; | |
671 | ||
bee1138b BG |
672 | rval = blocking_notifier_call_chain(&nvmem_notifier, NVMEM_ADD, nvmem); |
673 | if (rval) | |
674 | goto err_remove_cells; | |
675 | ||
eace75cf | 676 | return nvmem; |
3360acdf | 677 | |
b985f4cb BG |
678 | err_remove_cells: |
679 | nvmem_device_remove_all_cells(nvmem); | |
fa72d847 BG |
680 | err_teardown_compat: |
681 | if (config->compat) | |
682 | device_remove_bin_file(nvmem->base_dev, &nvmem->eeprom); | |
3360acdf JH |
683 | err_device_del: |
684 | device_del(&nvmem->dev); | |
685 | err_put_device: | |
686 | put_device(&nvmem->dev); | |
687 | ||
b6c217ab | 688 | return ERR_PTR(rval); |
eace75cf SK |
689 | } |
690 | EXPORT_SYMBOL_GPL(nvmem_register); | |
691 | ||
c1de7f43 BG |
692 | static void nvmem_device_release(struct kref *kref) |
693 | { | |
694 | struct nvmem_device *nvmem; | |
695 | ||
696 | nvmem = container_of(kref, struct nvmem_device, refcnt); | |
697 | ||
bee1138b BG |
698 | blocking_notifier_call_chain(&nvmem_notifier, NVMEM_REMOVE, nvmem); |
699 | ||
c1de7f43 BG |
700 | if (nvmem->flags & FLAG_COMPAT) |
701 | device_remove_bin_file(nvmem->base_dev, &nvmem->eeprom); | |
702 | ||
703 | nvmem_device_remove_all_cells(nvmem); | |
704 | device_del(&nvmem->dev); | |
705 | put_device(&nvmem->dev); | |
706 | } | |
707 | ||
eace75cf SK |
708 | /** |
709 | * nvmem_unregister() - Unregister previously registered nvmem device | |
710 | * | |
711 | * @nvmem: Pointer to previously registered nvmem device. | |
eace75cf | 712 | */ |
bf58e882 | 713 | void nvmem_unregister(struct nvmem_device *nvmem) |
eace75cf | 714 | { |
c1de7f43 | 715 | kref_put(&nvmem->refcnt, nvmem_device_release); |
eace75cf SK |
716 | } |
717 | EXPORT_SYMBOL_GPL(nvmem_unregister); | |
718 | ||
f1f50eca AS |
719 | static void devm_nvmem_release(struct device *dev, void *res) |
720 | { | |
bf58e882 | 721 | nvmem_unregister(*(struct nvmem_device **)res); |
f1f50eca AS |
722 | } |
723 | ||
724 | /** | |
725 | * devm_nvmem_register() - Register a managed nvmem device for given | |
726 | * nvmem_config. | |
727 | * Also creates an binary entry in /sys/bus/nvmem/devices/dev-name/nvmem | |
728 | * | |
b378c779 | 729 | * @dev: Device that uses the nvmem device. |
f1f50eca AS |
730 | * @config: nvmem device configuration with which nvmem device is created. |
731 | * | |
732 | * Return: Will be an ERR_PTR() on error or a valid pointer to nvmem_device | |
733 | * on success. | |
734 | */ | |
735 | struct nvmem_device *devm_nvmem_register(struct device *dev, | |
736 | const struct nvmem_config *config) | |
737 | { | |
738 | struct nvmem_device **ptr, *nvmem; | |
739 | ||
740 | ptr = devres_alloc(devm_nvmem_release, sizeof(*ptr), GFP_KERNEL); | |
741 | if (!ptr) | |
742 | return ERR_PTR(-ENOMEM); | |
743 | ||
744 | nvmem = nvmem_register(config); | |
745 | ||
746 | if (!IS_ERR(nvmem)) { | |
747 | *ptr = nvmem; | |
748 | devres_add(dev, ptr); | |
749 | } else { | |
750 | devres_free(ptr); | |
751 | } | |
752 | ||
753 | return nvmem; | |
754 | } | |
755 | EXPORT_SYMBOL_GPL(devm_nvmem_register); | |
756 | ||
757 | static int devm_nvmem_match(struct device *dev, void *res, void *data) | |
758 | { | |
759 | struct nvmem_device **r = res; | |
760 | ||
761 | return *r == data; | |
762 | } | |
763 | ||
764 | /** | |
765 | * devm_nvmem_unregister() - Unregister previously registered managed nvmem | |
766 | * device. | |
767 | * | |
b378c779 | 768 | * @dev: Device that uses the nvmem device. |
f1f50eca AS |
769 | * @nvmem: Pointer to previously registered nvmem device. |
770 | * | |
771 | * Return: Will be an negative on error or a zero on success. | |
772 | */ | |
773 | int devm_nvmem_unregister(struct device *dev, struct nvmem_device *nvmem) | |
774 | { | |
775 | return devres_release(dev, devm_nvmem_release, devm_nvmem_match, nvmem); | |
776 | } | |
777 | EXPORT_SYMBOL(devm_nvmem_unregister); | |
778 | ||
69aba794 | 779 | static struct nvmem_device *__nvmem_device_get(struct device_node *np, |
506157be | 780 | const char *nvmem_name) |
69aba794 SK |
781 | { |
782 | struct nvmem_device *nvmem = NULL; | |
783 | ||
c7235ee3 | 784 | mutex_lock(&nvmem_mutex); |
506157be | 785 | nvmem = np ? of_nvmem_find(np) : nvmem_find(nvmem_name); |
69aba794 | 786 | mutex_unlock(&nvmem_mutex); |
c7235ee3 BG |
787 | if (!nvmem) |
788 | return ERR_PTR(-EPROBE_DEFER); | |
69aba794 SK |
789 | |
790 | if (!try_module_get(nvmem->owner)) { | |
791 | dev_err(&nvmem->dev, | |
792 | "could not increase module refcount for cell %s\n", | |
5db652c9 | 793 | nvmem_dev_name(nvmem)); |
69aba794 | 794 | |
69aba794 SK |
795 | return ERR_PTR(-EINVAL); |
796 | } | |
797 | ||
c1de7f43 BG |
798 | kref_get(&nvmem->refcnt); |
799 | ||
69aba794 SK |
800 | return nvmem; |
801 | } | |
802 | ||
803 | static void __nvmem_device_put(struct nvmem_device *nvmem) | |
804 | { | |
805 | module_put(nvmem->owner); | |
c1de7f43 | 806 | kref_put(&nvmem->refcnt, nvmem_device_release); |
69aba794 SK |
807 | } |
808 | ||
e701c67c | 809 | #if IS_ENABLED(CONFIG_OF) |
e2a5402e SK |
810 | /** |
811 | * of_nvmem_device_get() - Get nvmem device from a given id | |
812 | * | |
29143268 | 813 | * @np: Device tree node that uses the nvmem device. |
e2a5402e SK |
814 | * @id: nvmem name from nvmem-names property. |
815 | * | |
816 | * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_device | |
817 | * on success. | |
818 | */ | |
819 | struct nvmem_device *of_nvmem_device_get(struct device_node *np, const char *id) | |
820 | { | |
821 | ||
822 | struct device_node *nvmem_np; | |
823 | int index; | |
824 | ||
825 | index = of_property_match_string(np, "nvmem-names", id); | |
826 | ||
827 | nvmem_np = of_parse_phandle(np, "nvmem", index); | |
828 | if (!nvmem_np) | |
829 | return ERR_PTR(-EINVAL); | |
830 | ||
506157be | 831 | return __nvmem_device_get(nvmem_np, NULL); |
e2a5402e SK |
832 | } |
833 | EXPORT_SYMBOL_GPL(of_nvmem_device_get); | |
834 | #endif | |
835 | ||
836 | /** | |
837 | * nvmem_device_get() - Get nvmem device from a given id | |
838 | * | |
29143268 VG |
839 | * @dev: Device that uses the nvmem device. |
840 | * @dev_name: name of the requested nvmem device. | |
e2a5402e SK |
841 | * |
842 | * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_device | |
843 | * on success. | |
844 | */ | |
845 | struct nvmem_device *nvmem_device_get(struct device *dev, const char *dev_name) | |
846 | { | |
847 | if (dev->of_node) { /* try dt first */ | |
848 | struct nvmem_device *nvmem; | |
849 | ||
850 | nvmem = of_nvmem_device_get(dev->of_node, dev_name); | |
851 | ||
852 | if (!IS_ERR(nvmem) || PTR_ERR(nvmem) == -EPROBE_DEFER) | |
853 | return nvmem; | |
854 | ||
855 | } | |
856 | ||
857 | return nvmem_find(dev_name); | |
858 | } | |
859 | EXPORT_SYMBOL_GPL(nvmem_device_get); | |
860 | ||
861 | static int devm_nvmem_device_match(struct device *dev, void *res, void *data) | |
862 | { | |
863 | struct nvmem_device **nvmem = res; | |
864 | ||
865 | if (WARN_ON(!nvmem || !*nvmem)) | |
866 | return 0; | |
867 | ||
868 | return *nvmem == data; | |
869 | } | |
870 | ||
871 | static void devm_nvmem_device_release(struct device *dev, void *res) | |
872 | { | |
873 | nvmem_device_put(*(struct nvmem_device **)res); | |
874 | } | |
875 | ||
876 | /** | |
877 | * devm_nvmem_device_put() - put alredy got nvmem device | |
878 | * | |
29143268 | 879 | * @dev: Device that uses the nvmem device. |
e2a5402e SK |
880 | * @nvmem: pointer to nvmem device allocated by devm_nvmem_cell_get(), |
881 | * that needs to be released. | |
882 | */ | |
883 | void devm_nvmem_device_put(struct device *dev, struct nvmem_device *nvmem) | |
884 | { | |
885 | int ret; | |
886 | ||
887 | ret = devres_release(dev, devm_nvmem_device_release, | |
888 | devm_nvmem_device_match, nvmem); | |
889 | ||
890 | WARN_ON(ret); | |
891 | } | |
892 | EXPORT_SYMBOL_GPL(devm_nvmem_device_put); | |
893 | ||
894 | /** | |
895 | * nvmem_device_put() - put alredy got nvmem device | |
896 | * | |
897 | * @nvmem: pointer to nvmem device that needs to be released. | |
898 | */ | |
899 | void nvmem_device_put(struct nvmem_device *nvmem) | |
900 | { | |
901 | __nvmem_device_put(nvmem); | |
902 | } | |
903 | EXPORT_SYMBOL_GPL(nvmem_device_put); | |
904 | ||
905 | /** | |
906 | * devm_nvmem_device_get() - Get nvmem cell of device form a given id | |
907 | * | |
29143268 VG |
908 | * @dev: Device that requests the nvmem device. |
909 | * @id: name id for the requested nvmem device. | |
e2a5402e SK |
910 | * |
911 | * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_cell | |
912 | * on success. The nvmem_cell will be freed by the automatically once the | |
913 | * device is freed. | |
914 | */ | |
915 | struct nvmem_device *devm_nvmem_device_get(struct device *dev, const char *id) | |
916 | { | |
917 | struct nvmem_device **ptr, *nvmem; | |
918 | ||
919 | ptr = devres_alloc(devm_nvmem_device_release, sizeof(*ptr), GFP_KERNEL); | |
920 | if (!ptr) | |
921 | return ERR_PTR(-ENOMEM); | |
922 | ||
923 | nvmem = nvmem_device_get(dev, id); | |
924 | if (!IS_ERR(nvmem)) { | |
925 | *ptr = nvmem; | |
926 | devres_add(dev, ptr); | |
927 | } else { | |
928 | devres_free(ptr); | |
929 | } | |
930 | ||
931 | return nvmem; | |
932 | } | |
933 | EXPORT_SYMBOL_GPL(devm_nvmem_device_get); | |
934 | ||
506157be BG |
935 | static struct nvmem_cell * |
936 | nvmem_cell_get_from_lookup(struct device *dev, const char *con_id) | |
69aba794 | 937 | { |
506157be BG |
938 | struct nvmem_cell *cell = ERR_PTR(-ENOENT); |
939 | struct nvmem_cell_lookup *lookup; | |
69aba794 | 940 | struct nvmem_device *nvmem; |
506157be | 941 | const char *dev_id; |
69aba794 | 942 | |
506157be BG |
943 | if (!dev) |
944 | return ERR_PTR(-EINVAL); | |
945 | ||
946 | dev_id = dev_name(dev); | |
947 | ||
948 | mutex_lock(&nvmem_lookup_mutex); | |
949 | ||
950 | list_for_each_entry(lookup, &nvmem_lookup_list, node) { | |
951 | if ((strcmp(lookup->dev_id, dev_id) == 0) && | |
952 | (strcmp(lookup->con_id, con_id) == 0)) { | |
953 | /* This is the right entry. */ | |
954 | nvmem = __nvmem_device_get(NULL, lookup->nvmem_name); | |
955 | if (!nvmem) { | |
956 | /* Provider may not be registered yet. */ | |
957 | cell = ERR_PTR(-EPROBE_DEFER); | |
958 | goto out; | |
959 | } | |
960 | ||
961 | cell = nvmem_find_cell_by_name(nvmem, | |
962 | lookup->cell_name); | |
963 | if (!cell) { | |
964 | __nvmem_device_put(nvmem); | |
965 | goto out; | |
966 | } | |
967 | } | |
968 | } | |
69aba794 | 969 | |
506157be BG |
970 | out: |
971 | mutex_unlock(&nvmem_lookup_mutex); | |
69aba794 SK |
972 | return cell; |
973 | } | |
974 | ||
e701c67c | 975 | #if IS_ENABLED(CONFIG_OF) |
69aba794 SK |
976 | /** |
977 | * of_nvmem_cell_get() - Get a nvmem cell from given device node and cell id | |
978 | * | |
29143268 | 979 | * @np: Device tree node that uses the nvmem cell. |
fd0c478c VG |
980 | * @name: nvmem cell name from nvmem-cell-names property, or NULL |
981 | * for the cell at index 0 (the lone cell with no accompanying | |
982 | * nvmem-cell-names property). | |
69aba794 SK |
983 | * |
984 | * Return: Will be an ERR_PTR() on error or a valid pointer | |
985 | * to a struct nvmem_cell. The nvmem_cell will be freed by the | |
986 | * nvmem_cell_put(). | |
987 | */ | |
988 | struct nvmem_cell *of_nvmem_cell_get(struct device_node *np, | |
989 | const char *name) | |
990 | { | |
991 | struct device_node *cell_np, *nvmem_np; | |
69aba794 | 992 | struct nvmem_device *nvmem; |
e888d445 | 993 | struct nvmem_cell *cell; |
fd0c478c | 994 | int index = 0; |
69aba794 | 995 | |
fd0c478c VG |
996 | /* if cell name exists, find index to the name */ |
997 | if (name) | |
998 | index = of_property_match_string(np, "nvmem-cell-names", name); | |
69aba794 SK |
999 | |
1000 | cell_np = of_parse_phandle(np, "nvmem-cells", index); | |
1001 | if (!cell_np) | |
1002 | return ERR_PTR(-EINVAL); | |
1003 | ||
1004 | nvmem_np = of_get_next_parent(cell_np); | |
1005 | if (!nvmem_np) | |
1006 | return ERR_PTR(-EINVAL); | |
1007 | ||
506157be | 1008 | nvmem = __nvmem_device_get(nvmem_np, NULL); |
aad8d097 | 1009 | of_node_put(nvmem_np); |
69aba794 SK |
1010 | if (IS_ERR(nvmem)) |
1011 | return ERR_CAST(nvmem); | |
1012 | ||
e888d445 | 1013 | cell = nvmem_find_cell_by_index(nvmem, index); |
69aba794 | 1014 | if (!cell) { |
e888d445 BG |
1015 | __nvmem_device_put(nvmem); |
1016 | return ERR_PTR(-ENOENT); | |
69aba794 SK |
1017 | } |
1018 | ||
69aba794 | 1019 | return cell; |
69aba794 SK |
1020 | } |
1021 | EXPORT_SYMBOL_GPL(of_nvmem_cell_get); | |
1022 | #endif | |
1023 | ||
1024 | /** | |
1025 | * nvmem_cell_get() - Get nvmem cell of device form a given cell name | |
1026 | * | |
29143268 VG |
1027 | * @dev: Device that requests the nvmem cell. |
1028 | * @cell_id: nvmem cell name to get. | |
69aba794 SK |
1029 | * |
1030 | * Return: Will be an ERR_PTR() on error or a valid pointer | |
1031 | * to a struct nvmem_cell. The nvmem_cell will be freed by the | |
1032 | * nvmem_cell_put(). | |
1033 | */ | |
1034 | struct nvmem_cell *nvmem_cell_get(struct device *dev, const char *cell_id) | |
1035 | { | |
1036 | struct nvmem_cell *cell; | |
1037 | ||
1038 | if (dev->of_node) { /* try dt first */ | |
1039 | cell = of_nvmem_cell_get(dev->of_node, cell_id); | |
1040 | if (!IS_ERR(cell) || PTR_ERR(cell) == -EPROBE_DEFER) | |
1041 | return cell; | |
1042 | } | |
1043 | ||
87ed1405 DA |
1044 | /* NULL cell_id only allowed for device tree; invalid otherwise */ |
1045 | if (!cell_id) | |
1046 | return ERR_PTR(-EINVAL); | |
1047 | ||
506157be | 1048 | return nvmem_cell_get_from_lookup(dev, cell_id); |
69aba794 SK |
1049 | } |
1050 | EXPORT_SYMBOL_GPL(nvmem_cell_get); | |
1051 | ||
1052 | static void devm_nvmem_cell_release(struct device *dev, void *res) | |
1053 | { | |
1054 | nvmem_cell_put(*(struct nvmem_cell **)res); | |
1055 | } | |
1056 | ||
1057 | /** | |
1058 | * devm_nvmem_cell_get() - Get nvmem cell of device form a given id | |
1059 | * | |
29143268 VG |
1060 | * @dev: Device that requests the nvmem cell. |
1061 | * @id: nvmem cell name id to get. | |
69aba794 SK |
1062 | * |
1063 | * Return: Will be an ERR_PTR() on error or a valid pointer | |
1064 | * to a struct nvmem_cell. The nvmem_cell will be freed by the | |
1065 | * automatically once the device is freed. | |
1066 | */ | |
1067 | struct nvmem_cell *devm_nvmem_cell_get(struct device *dev, const char *id) | |
1068 | { | |
1069 | struct nvmem_cell **ptr, *cell; | |
1070 | ||
1071 | ptr = devres_alloc(devm_nvmem_cell_release, sizeof(*ptr), GFP_KERNEL); | |
1072 | if (!ptr) | |
1073 | return ERR_PTR(-ENOMEM); | |
1074 | ||
1075 | cell = nvmem_cell_get(dev, id); | |
1076 | if (!IS_ERR(cell)) { | |
1077 | *ptr = cell; | |
1078 | devres_add(dev, ptr); | |
1079 | } else { | |
1080 | devres_free(ptr); | |
1081 | } | |
1082 | ||
1083 | return cell; | |
1084 | } | |
1085 | EXPORT_SYMBOL_GPL(devm_nvmem_cell_get); | |
1086 | ||
1087 | static int devm_nvmem_cell_match(struct device *dev, void *res, void *data) | |
1088 | { | |
1089 | struct nvmem_cell **c = res; | |
1090 | ||
1091 | if (WARN_ON(!c || !*c)) | |
1092 | return 0; | |
1093 | ||
1094 | return *c == data; | |
1095 | } | |
1096 | ||
1097 | /** | |
1098 | * devm_nvmem_cell_put() - Release previously allocated nvmem cell | |
1099 | * from devm_nvmem_cell_get. | |
1100 | * | |
29143268 VG |
1101 | * @dev: Device that requests the nvmem cell. |
1102 | * @cell: Previously allocated nvmem cell by devm_nvmem_cell_get(). | |
69aba794 SK |
1103 | */ |
1104 | void devm_nvmem_cell_put(struct device *dev, struct nvmem_cell *cell) | |
1105 | { | |
1106 | int ret; | |
1107 | ||
1108 | ret = devres_release(dev, devm_nvmem_cell_release, | |
1109 | devm_nvmem_cell_match, cell); | |
1110 | ||
1111 | WARN_ON(ret); | |
1112 | } | |
1113 | EXPORT_SYMBOL(devm_nvmem_cell_put); | |
1114 | ||
1115 | /** | |
1116 | * nvmem_cell_put() - Release previously allocated nvmem cell. | |
1117 | * | |
29143268 | 1118 | * @cell: Previously allocated nvmem cell by nvmem_cell_get(). |
69aba794 SK |
1119 | */ |
1120 | void nvmem_cell_put(struct nvmem_cell *cell) | |
1121 | { | |
1122 | struct nvmem_device *nvmem = cell->nvmem; | |
1123 | ||
1124 | __nvmem_device_put(nvmem); | |
69aba794 SK |
1125 | } |
1126 | EXPORT_SYMBOL_GPL(nvmem_cell_put); | |
1127 | ||
f7c04f16 | 1128 | static void nvmem_shift_read_buffer_in_place(struct nvmem_cell *cell, void *buf) |
69aba794 SK |
1129 | { |
1130 | u8 *p, *b; | |
1131 | int i, bit_offset = cell->bit_offset; | |
1132 | ||
1133 | p = b = buf; | |
1134 | if (bit_offset) { | |
1135 | /* First shift */ | |
1136 | *b++ >>= bit_offset; | |
1137 | ||
1138 | /* setup rest of the bytes if any */ | |
1139 | for (i = 1; i < cell->bytes; i++) { | |
1140 | /* Get bits from next byte and shift them towards msb */ | |
1141 | *p |= *b << (BITS_PER_BYTE - bit_offset); | |
1142 | ||
1143 | p = b; | |
1144 | *b++ >>= bit_offset; | |
1145 | } | |
1146 | ||
1147 | /* result fits in less bytes */ | |
1148 | if (cell->bytes != DIV_ROUND_UP(cell->nbits, BITS_PER_BYTE)) | |
1149 | *p-- = 0; | |
1150 | } | |
1151 | /* clear msb bits if any leftover in the last byte */ | |
1152 | *p &= GENMASK((cell->nbits%BITS_PER_BYTE) - 1, 0); | |
1153 | } | |
1154 | ||
1155 | static int __nvmem_cell_read(struct nvmem_device *nvmem, | |
1156 | struct nvmem_cell *cell, | |
1157 | void *buf, size_t *len) | |
1158 | { | |
1159 | int rc; | |
1160 | ||
795ddd18 | 1161 | rc = nvmem_reg_read(nvmem, cell->offset, buf, cell->bytes); |
69aba794 | 1162 | |
287980e4 | 1163 | if (rc) |
69aba794 SK |
1164 | return rc; |
1165 | ||
1166 | /* shift bits in-place */ | |
cbf854ab | 1167 | if (cell->bit_offset || cell->nbits) |
69aba794 SK |
1168 | nvmem_shift_read_buffer_in_place(cell, buf); |
1169 | ||
3b4a6877 VG |
1170 | if (len) |
1171 | *len = cell->bytes; | |
69aba794 SK |
1172 | |
1173 | return 0; | |
1174 | } | |
1175 | ||
1176 | /** | |
1177 | * nvmem_cell_read() - Read a given nvmem cell | |
1178 | * | |
1179 | * @cell: nvmem cell to be read. | |
3b4a6877 VG |
1180 | * @len: pointer to length of cell which will be populated on successful read; |
1181 | * can be NULL. | |
69aba794 | 1182 | * |
b577fafc BN |
1183 | * Return: ERR_PTR() on error or a valid pointer to a buffer on success. The |
1184 | * buffer should be freed by the consumer with a kfree(). | |
69aba794 SK |
1185 | */ |
1186 | void *nvmem_cell_read(struct nvmem_cell *cell, size_t *len) | |
1187 | { | |
1188 | struct nvmem_device *nvmem = cell->nvmem; | |
1189 | u8 *buf; | |
1190 | int rc; | |
1191 | ||
795ddd18 | 1192 | if (!nvmem) |
69aba794 SK |
1193 | return ERR_PTR(-EINVAL); |
1194 | ||
1195 | buf = kzalloc(cell->bytes, GFP_KERNEL); | |
1196 | if (!buf) | |
1197 | return ERR_PTR(-ENOMEM); | |
1198 | ||
1199 | rc = __nvmem_cell_read(nvmem, cell, buf, len); | |
287980e4 | 1200 | if (rc) { |
69aba794 SK |
1201 | kfree(buf); |
1202 | return ERR_PTR(rc); | |
1203 | } | |
1204 | ||
1205 | return buf; | |
1206 | } | |
1207 | EXPORT_SYMBOL_GPL(nvmem_cell_read); | |
1208 | ||
f7c04f16 MY |
1209 | static void *nvmem_cell_prepare_write_buffer(struct nvmem_cell *cell, |
1210 | u8 *_buf, int len) | |
69aba794 SK |
1211 | { |
1212 | struct nvmem_device *nvmem = cell->nvmem; | |
1213 | int i, rc, nbits, bit_offset = cell->bit_offset; | |
1214 | u8 v, *p, *buf, *b, pbyte, pbits; | |
1215 | ||
1216 | nbits = cell->nbits; | |
1217 | buf = kzalloc(cell->bytes, GFP_KERNEL); | |
1218 | if (!buf) | |
1219 | return ERR_PTR(-ENOMEM); | |
1220 | ||
1221 | memcpy(buf, _buf, len); | |
1222 | p = b = buf; | |
1223 | ||
1224 | if (bit_offset) { | |
1225 | pbyte = *b; | |
1226 | *b <<= bit_offset; | |
1227 | ||
1228 | /* setup the first byte with lsb bits from nvmem */ | |
795ddd18 | 1229 | rc = nvmem_reg_read(nvmem, cell->offset, &v, 1); |
50808bfc MM |
1230 | if (rc) |
1231 | goto err; | |
69aba794 SK |
1232 | *b++ |= GENMASK(bit_offset - 1, 0) & v; |
1233 | ||
1234 | /* setup rest of the byte if any */ | |
1235 | for (i = 1; i < cell->bytes; i++) { | |
1236 | /* Get last byte bits and shift them towards lsb */ | |
1237 | pbits = pbyte >> (BITS_PER_BYTE - 1 - bit_offset); | |
1238 | pbyte = *b; | |
1239 | p = b; | |
1240 | *b <<= bit_offset; | |
1241 | *b++ |= pbits; | |
1242 | } | |
1243 | } | |
1244 | ||
1245 | /* if it's not end on byte boundary */ | |
1246 | if ((nbits + bit_offset) % BITS_PER_BYTE) { | |
1247 | /* setup the last byte with msb bits from nvmem */ | |
795ddd18 | 1248 | rc = nvmem_reg_read(nvmem, |
69aba794 | 1249 | cell->offset + cell->bytes - 1, &v, 1); |
50808bfc MM |
1250 | if (rc) |
1251 | goto err; | |
69aba794 SK |
1252 | *p |= GENMASK(7, (nbits + bit_offset) % BITS_PER_BYTE) & v; |
1253 | ||
1254 | } | |
1255 | ||
1256 | return buf; | |
50808bfc MM |
1257 | err: |
1258 | kfree(buf); | |
1259 | return ERR_PTR(rc); | |
69aba794 SK |
1260 | } |
1261 | ||
1262 | /** | |
1263 | * nvmem_cell_write() - Write to a given nvmem cell | |
1264 | * | |
1265 | * @cell: nvmem cell to be written. | |
1266 | * @buf: Buffer to be written. | |
1267 | * @len: length of buffer to be written to nvmem cell. | |
1268 | * | |
1269 | * Return: length of bytes written or negative on failure. | |
1270 | */ | |
1271 | int nvmem_cell_write(struct nvmem_cell *cell, void *buf, size_t len) | |
1272 | { | |
1273 | struct nvmem_device *nvmem = cell->nvmem; | |
1274 | int rc; | |
1275 | ||
795ddd18 | 1276 | if (!nvmem || nvmem->read_only || |
69aba794 SK |
1277 | (cell->bit_offset == 0 && len != cell->bytes)) |
1278 | return -EINVAL; | |
1279 | ||
1280 | if (cell->bit_offset || cell->nbits) { | |
1281 | buf = nvmem_cell_prepare_write_buffer(cell, buf, len); | |
1282 | if (IS_ERR(buf)) | |
1283 | return PTR_ERR(buf); | |
1284 | } | |
1285 | ||
795ddd18 | 1286 | rc = nvmem_reg_write(nvmem, cell->offset, buf, cell->bytes); |
69aba794 SK |
1287 | |
1288 | /* free the tmp buffer */ | |
ace22170 | 1289 | if (cell->bit_offset || cell->nbits) |
69aba794 SK |
1290 | kfree(buf); |
1291 | ||
287980e4 | 1292 | if (rc) |
69aba794 SK |
1293 | return rc; |
1294 | ||
1295 | return len; | |
1296 | } | |
1297 | EXPORT_SYMBOL_GPL(nvmem_cell_write); | |
1298 | ||
d026d70a LC |
1299 | /** |
1300 | * nvmem_cell_read_u32() - Read a cell value as an u32 | |
1301 | * | |
1302 | * @dev: Device that requests the nvmem cell. | |
1303 | * @cell_id: Name of nvmem cell to read. | |
1304 | * @val: pointer to output value. | |
1305 | * | |
1306 | * Return: 0 on success or negative errno. | |
1307 | */ | |
1308 | int nvmem_cell_read_u32(struct device *dev, const char *cell_id, u32 *val) | |
1309 | { | |
1310 | struct nvmem_cell *cell; | |
1311 | void *buf; | |
1312 | size_t len; | |
1313 | ||
1314 | cell = nvmem_cell_get(dev, cell_id); | |
1315 | if (IS_ERR(cell)) | |
1316 | return PTR_ERR(cell); | |
1317 | ||
1318 | buf = nvmem_cell_read(cell, &len); | |
1319 | if (IS_ERR(buf)) { | |
1320 | nvmem_cell_put(cell); | |
1321 | return PTR_ERR(buf); | |
1322 | } | |
1323 | if (len != sizeof(*val)) { | |
1324 | kfree(buf); | |
1325 | nvmem_cell_put(cell); | |
1326 | return -EINVAL; | |
1327 | } | |
1328 | memcpy(val, buf, sizeof(*val)); | |
1329 | ||
1330 | kfree(buf); | |
1331 | nvmem_cell_put(cell); | |
1332 | return 0; | |
1333 | } | |
1334 | EXPORT_SYMBOL_GPL(nvmem_cell_read_u32); | |
1335 | ||
e2a5402e SK |
1336 | /** |
1337 | * nvmem_device_cell_read() - Read a given nvmem device and cell | |
1338 | * | |
1339 | * @nvmem: nvmem device to read from. | |
1340 | * @info: nvmem cell info to be read. | |
1341 | * @buf: buffer pointer which will be populated on successful read. | |
1342 | * | |
1343 | * Return: length of successful bytes read on success and negative | |
1344 | * error code on error. | |
1345 | */ | |
1346 | ssize_t nvmem_device_cell_read(struct nvmem_device *nvmem, | |
1347 | struct nvmem_cell_info *info, void *buf) | |
1348 | { | |
1349 | struct nvmem_cell cell; | |
1350 | int rc; | |
1351 | ssize_t len; | |
1352 | ||
795ddd18 | 1353 | if (!nvmem) |
e2a5402e SK |
1354 | return -EINVAL; |
1355 | ||
1356 | rc = nvmem_cell_info_to_nvmem_cell(nvmem, info, &cell); | |
287980e4 | 1357 | if (rc) |
e2a5402e SK |
1358 | return rc; |
1359 | ||
1360 | rc = __nvmem_cell_read(nvmem, &cell, buf, &len); | |
287980e4 | 1361 | if (rc) |
e2a5402e SK |
1362 | return rc; |
1363 | ||
1364 | return len; | |
1365 | } | |
1366 | EXPORT_SYMBOL_GPL(nvmem_device_cell_read); | |
1367 | ||
1368 | /** | |
1369 | * nvmem_device_cell_write() - Write cell to a given nvmem device | |
1370 | * | |
1371 | * @nvmem: nvmem device to be written to. | |
29143268 | 1372 | * @info: nvmem cell info to be written. |
e2a5402e SK |
1373 | * @buf: buffer to be written to cell. |
1374 | * | |
1375 | * Return: length of bytes written or negative error code on failure. | |
1376 | * */ | |
1377 | int nvmem_device_cell_write(struct nvmem_device *nvmem, | |
1378 | struct nvmem_cell_info *info, void *buf) | |
1379 | { | |
1380 | struct nvmem_cell cell; | |
1381 | int rc; | |
1382 | ||
795ddd18 | 1383 | if (!nvmem) |
e2a5402e SK |
1384 | return -EINVAL; |
1385 | ||
1386 | rc = nvmem_cell_info_to_nvmem_cell(nvmem, info, &cell); | |
287980e4 | 1387 | if (rc) |
e2a5402e SK |
1388 | return rc; |
1389 | ||
1390 | return nvmem_cell_write(&cell, buf, cell.bytes); | |
1391 | } | |
1392 | EXPORT_SYMBOL_GPL(nvmem_device_cell_write); | |
1393 | ||
1394 | /** | |
1395 | * nvmem_device_read() - Read from a given nvmem device | |
1396 | * | |
1397 | * @nvmem: nvmem device to read from. | |
1398 | * @offset: offset in nvmem device. | |
1399 | * @bytes: number of bytes to read. | |
1400 | * @buf: buffer pointer which will be populated on successful read. | |
1401 | * | |
1402 | * Return: length of successful bytes read on success and negative | |
1403 | * error code on error. | |
1404 | */ | |
1405 | int nvmem_device_read(struct nvmem_device *nvmem, | |
1406 | unsigned int offset, | |
1407 | size_t bytes, void *buf) | |
1408 | { | |
1409 | int rc; | |
1410 | ||
795ddd18 | 1411 | if (!nvmem) |
e2a5402e SK |
1412 | return -EINVAL; |
1413 | ||
795ddd18 | 1414 | rc = nvmem_reg_read(nvmem, offset, buf, bytes); |
e2a5402e | 1415 | |
287980e4 | 1416 | if (rc) |
e2a5402e SK |
1417 | return rc; |
1418 | ||
1419 | return bytes; | |
1420 | } | |
1421 | EXPORT_SYMBOL_GPL(nvmem_device_read); | |
1422 | ||
1423 | /** | |
1424 | * nvmem_device_write() - Write cell to a given nvmem device | |
1425 | * | |
1426 | * @nvmem: nvmem device to be written to. | |
1427 | * @offset: offset in nvmem device. | |
1428 | * @bytes: number of bytes to write. | |
1429 | * @buf: buffer to be written. | |
1430 | * | |
1431 | * Return: length of bytes written or negative error code on failure. | |
1432 | * */ | |
1433 | int nvmem_device_write(struct nvmem_device *nvmem, | |
1434 | unsigned int offset, | |
1435 | size_t bytes, void *buf) | |
1436 | { | |
1437 | int rc; | |
1438 | ||
795ddd18 | 1439 | if (!nvmem) |
e2a5402e SK |
1440 | return -EINVAL; |
1441 | ||
795ddd18 | 1442 | rc = nvmem_reg_write(nvmem, offset, buf, bytes); |
e2a5402e | 1443 | |
287980e4 | 1444 | if (rc) |
e2a5402e SK |
1445 | return rc; |
1446 | ||
1447 | ||
1448 | return bytes; | |
1449 | } | |
1450 | EXPORT_SYMBOL_GPL(nvmem_device_write); | |
1451 | ||
b985f4cb BG |
1452 | /** |
1453 | * nvmem_add_cell_table() - register a table of cell info entries | |
1454 | * | |
1455 | * @table: table of cell info entries | |
1456 | */ | |
1457 | void nvmem_add_cell_table(struct nvmem_cell_table *table) | |
1458 | { | |
1459 | mutex_lock(&nvmem_cell_mutex); | |
1460 | list_add_tail(&table->node, &nvmem_cell_tables); | |
1461 | mutex_unlock(&nvmem_cell_mutex); | |
1462 | } | |
1463 | EXPORT_SYMBOL_GPL(nvmem_add_cell_table); | |
1464 | ||
1465 | /** | |
1466 | * nvmem_del_cell_table() - remove a previously registered cell info table | |
1467 | * | |
1468 | * @table: table of cell info entries | |
1469 | */ | |
1470 | void nvmem_del_cell_table(struct nvmem_cell_table *table) | |
1471 | { | |
1472 | mutex_lock(&nvmem_cell_mutex); | |
1473 | list_del(&table->node); | |
1474 | mutex_unlock(&nvmem_cell_mutex); | |
1475 | } | |
1476 | EXPORT_SYMBOL_GPL(nvmem_del_cell_table); | |
1477 | ||
506157be BG |
1478 | /** |
1479 | * nvmem_add_cell_lookups() - register a list of cell lookup entries | |
1480 | * | |
1481 | * @entries: array of cell lookup entries | |
1482 | * @nentries: number of cell lookup entries in the array | |
1483 | */ | |
1484 | void nvmem_add_cell_lookups(struct nvmem_cell_lookup *entries, size_t nentries) | |
1485 | { | |
1486 | int i; | |
1487 | ||
1488 | mutex_lock(&nvmem_lookup_mutex); | |
1489 | for (i = 0; i < nentries; i++) | |
1490 | list_add_tail(&entries[i].node, &nvmem_lookup_list); | |
1491 | mutex_unlock(&nvmem_lookup_mutex); | |
1492 | } | |
1493 | EXPORT_SYMBOL_GPL(nvmem_add_cell_lookups); | |
1494 | ||
1495 | /** | |
1496 | * nvmem_del_cell_lookups() - remove a list of previously added cell lookup | |
1497 | * entries | |
1498 | * | |
1499 | * @entries: array of cell lookup entries | |
1500 | * @nentries: number of cell lookup entries in the array | |
1501 | */ | |
1502 | void nvmem_del_cell_lookups(struct nvmem_cell_lookup *entries, size_t nentries) | |
1503 | { | |
1504 | int i; | |
1505 | ||
1506 | mutex_lock(&nvmem_lookup_mutex); | |
1507 | for (i = 0; i < nentries; i++) | |
1508 | list_del(&entries[i].node); | |
1509 | mutex_unlock(&nvmem_lookup_mutex); | |
1510 | } | |
1511 | EXPORT_SYMBOL_GPL(nvmem_del_cell_lookups); | |
1512 | ||
d7b9fd16 BG |
1513 | /** |
1514 | * nvmem_dev_name() - Get the name of a given nvmem device. | |
1515 | * | |
1516 | * @nvmem: nvmem device. | |
1517 | * | |
1518 | * Return: name of the nvmem device. | |
1519 | */ | |
1520 | const char *nvmem_dev_name(struct nvmem_device *nvmem) | |
1521 | { | |
1522 | return dev_name(&nvmem->dev); | |
1523 | } | |
1524 | EXPORT_SYMBOL_GPL(nvmem_dev_name); | |
1525 | ||
eace75cf SK |
1526 | static int __init nvmem_init(void) |
1527 | { | |
1528 | return bus_register(&nvmem_bus_type); | |
1529 | } | |
1530 | ||
1531 | static void __exit nvmem_exit(void) | |
1532 | { | |
1533 | bus_unregister(&nvmem_bus_type); | |
1534 | } | |
1535 | ||
1536 | subsys_initcall(nvmem_init); | |
1537 | module_exit(nvmem_exit); | |
1538 | ||
1539 | MODULE_AUTHOR("Srinivas Kandagatla <srinivas.kandagatla@linaro.org"); | |
1540 | MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com"); | |
1541 | MODULE_DESCRIPTION("nvmem Driver Core"); | |
1542 | MODULE_LICENSE("GPL v2"); |