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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> | |
2a127da4 | 18 | #include <linux/gpio/consumer.h> |
eace75cf | 19 | #include <linux/of.h> |
eace75cf | 20 | #include <linux/slab.h> |
84400305 SK |
21 | |
22 | struct nvmem_device { | |
23 | struct module *owner; | |
24 | struct device dev; | |
25 | int stride; | |
26 | int word_size; | |
27 | int id; | |
28 | struct kref refcnt; | |
29 | size_t size; | |
30 | bool read_only; | |
31 | bool root_only; | |
32 | int flags; | |
33 | enum nvmem_type type; | |
34 | struct bin_attribute eeprom; | |
35 | struct device *base_dev; | |
36 | struct list_head cells; | |
fd3bb8f5 EG |
37 | const struct nvmem_keepout *keepout; |
38 | unsigned int nkeepout; | |
84400305 SK |
39 | nvmem_reg_read_t reg_read; |
40 | nvmem_reg_write_t reg_write; | |
5008062f | 41 | nvmem_cell_post_process_t cell_post_process; |
84400305 SK |
42 | struct gpio_desc *wp_gpio; |
43 | void *priv; | |
44 | }; | |
45 | ||
46 | #define to_nvmem_device(d) container_of(d, struct nvmem_device, dev) | |
47 | ||
48 | #define FLAG_COMPAT BIT(0) | |
7ae6478b | 49 | struct nvmem_cell_entry { |
eace75cf SK |
50 | const char *name; |
51 | int offset; | |
52 | int bytes; | |
53 | int bit_offset; | |
54 | int nbits; | |
0749aa25 | 55 | struct device_node *np; |
eace75cf SK |
56 | struct nvmem_device *nvmem; |
57 | struct list_head node; | |
58 | }; | |
59 | ||
7ae6478b SK |
60 | struct nvmem_cell { |
61 | struct nvmem_cell_entry *entry; | |
62 | const char *id; | |
5d8e6e6c | 63 | int index; |
7ae6478b SK |
64 | }; |
65 | ||
eace75cf SK |
66 | static DEFINE_MUTEX(nvmem_mutex); |
67 | static DEFINE_IDA(nvmem_ida); | |
68 | ||
b985f4cb BG |
69 | static DEFINE_MUTEX(nvmem_cell_mutex); |
70 | static LIST_HEAD(nvmem_cell_tables); | |
71 | ||
506157be BG |
72 | static DEFINE_MUTEX(nvmem_lookup_mutex); |
73 | static LIST_HEAD(nvmem_lookup_list); | |
74 | ||
bee1138b BG |
75 | static BLOCKING_NOTIFIER_HEAD(nvmem_notifier); |
76 | ||
fd3bb8f5 EG |
77 | static int __nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset, |
78 | void *val, size_t bytes) | |
b96fc541 MA |
79 | { |
80 | if (nvmem->reg_read) | |
81 | return nvmem->reg_read(nvmem->priv, offset, val, bytes); | |
82 | ||
83 | return -EINVAL; | |
84 | } | |
85 | ||
fd3bb8f5 EG |
86 | static int __nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset, |
87 | void *val, size_t bytes) | |
b96fc541 MA |
88 | { |
89 | int ret; | |
90 | ||
91 | if (nvmem->reg_write) { | |
92 | gpiod_set_value_cansleep(nvmem->wp_gpio, 0); | |
93 | ret = nvmem->reg_write(nvmem->priv, offset, val, bytes); | |
94 | gpiod_set_value_cansleep(nvmem->wp_gpio, 1); | |
95 | return ret; | |
96 | } | |
97 | ||
98 | return -EINVAL; | |
99 | } | |
100 | ||
fd3bb8f5 EG |
101 | static int nvmem_access_with_keepouts(struct nvmem_device *nvmem, |
102 | unsigned int offset, void *val, | |
103 | size_t bytes, int write) | |
104 | { | |
105 | ||
106 | unsigned int end = offset + bytes; | |
107 | unsigned int kend, ksize; | |
108 | const struct nvmem_keepout *keepout = nvmem->keepout; | |
109 | const struct nvmem_keepout *keepoutend = keepout + nvmem->nkeepout; | |
110 | int rc; | |
111 | ||
112 | /* | |
113 | * Skip all keepouts before the range being accessed. | |
114 | * Keepouts are sorted. | |
115 | */ | |
116 | while ((keepout < keepoutend) && (keepout->end <= offset)) | |
117 | keepout++; | |
118 | ||
119 | while ((offset < end) && (keepout < keepoutend)) { | |
120 | /* Access the valid portion before the keepout. */ | |
121 | if (offset < keepout->start) { | |
122 | kend = min(end, keepout->start); | |
123 | ksize = kend - offset; | |
124 | if (write) | |
125 | rc = __nvmem_reg_write(nvmem, offset, val, ksize); | |
126 | else | |
127 | rc = __nvmem_reg_read(nvmem, offset, val, ksize); | |
128 | ||
129 | if (rc) | |
130 | return rc; | |
131 | ||
132 | offset += ksize; | |
133 | val += ksize; | |
134 | } | |
135 | ||
136 | /* | |
137 | * Now we're aligned to the start of this keepout zone. Go | |
138 | * through it. | |
139 | */ | |
140 | kend = min(end, keepout->end); | |
141 | ksize = kend - offset; | |
142 | if (!write) | |
143 | memset(val, keepout->value, ksize); | |
144 | ||
145 | val += ksize; | |
146 | offset += ksize; | |
147 | keepout++; | |
148 | } | |
149 | ||
150 | /* | |
151 | * If we ran out of keepouts but there's still stuff to do, send it | |
152 | * down directly | |
153 | */ | |
154 | if (offset < end) { | |
155 | ksize = end - offset; | |
156 | if (write) | |
157 | return __nvmem_reg_write(nvmem, offset, val, ksize); | |
158 | else | |
159 | return __nvmem_reg_read(nvmem, offset, val, ksize); | |
160 | } | |
161 | ||
162 | return 0; | |
163 | } | |
164 | ||
165 | static int nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset, | |
166 | void *val, size_t bytes) | |
167 | { | |
168 | if (!nvmem->nkeepout) | |
169 | return __nvmem_reg_read(nvmem, offset, val, bytes); | |
170 | ||
171 | return nvmem_access_with_keepouts(nvmem, offset, val, bytes, false); | |
172 | } | |
173 | ||
174 | static int nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset, | |
175 | void *val, size_t bytes) | |
176 | { | |
177 | if (!nvmem->nkeepout) | |
178 | return __nvmem_reg_write(nvmem, offset, val, bytes); | |
179 | ||
180 | return nvmem_access_with_keepouts(nvmem, offset, val, bytes, true); | |
181 | } | |
182 | ||
84400305 SK |
183 | #ifdef CONFIG_NVMEM_SYSFS |
184 | static const char * const nvmem_type_str[] = { | |
185 | [NVMEM_TYPE_UNKNOWN] = "Unknown", | |
186 | [NVMEM_TYPE_EEPROM] = "EEPROM", | |
187 | [NVMEM_TYPE_OTP] = "OTP", | |
188 | [NVMEM_TYPE_BATTERY_BACKED] = "Battery backed", | |
fd307a4a | 189 | [NVMEM_TYPE_FRAM] = "FRAM", |
84400305 SK |
190 | }; |
191 | ||
192 | #ifdef CONFIG_DEBUG_LOCK_ALLOC | |
193 | static struct lock_class_key eeprom_lock_key; | |
194 | #endif | |
195 | ||
196 | static ssize_t type_show(struct device *dev, | |
197 | struct device_attribute *attr, char *buf) | |
198 | { | |
199 | struct nvmem_device *nvmem = to_nvmem_device(dev); | |
200 | ||
201 | return sprintf(buf, "%s\n", nvmem_type_str[nvmem->type]); | |
202 | } | |
203 | ||
204 | static DEVICE_ATTR_RO(type); | |
205 | ||
206 | static struct attribute *nvmem_attrs[] = { | |
207 | &dev_attr_type.attr, | |
208 | NULL, | |
209 | }; | |
210 | ||
211 | static ssize_t bin_attr_nvmem_read(struct file *filp, struct kobject *kobj, | |
212 | struct bin_attribute *attr, char *buf, | |
213 | loff_t pos, size_t count) | |
214 | { | |
215 | struct device *dev; | |
216 | struct nvmem_device *nvmem; | |
217 | int rc; | |
218 | ||
219 | if (attr->private) | |
220 | dev = attr->private; | |
221 | else | |
28371cc6 | 222 | dev = kobj_to_dev(kobj); |
84400305 SK |
223 | nvmem = to_nvmem_device(dev); |
224 | ||
225 | /* Stop the user from reading */ | |
226 | if (pos >= nvmem->size) | |
227 | return 0; | |
228 | ||
83566715 DA |
229 | if (!IS_ALIGNED(pos, nvmem->stride)) |
230 | return -EINVAL; | |
231 | ||
84400305 SK |
232 | if (count < nvmem->word_size) |
233 | return -EINVAL; | |
234 | ||
235 | if (pos + count > nvmem->size) | |
236 | count = nvmem->size - pos; | |
237 | ||
238 | count = round_down(count, nvmem->word_size); | |
239 | ||
240 | if (!nvmem->reg_read) | |
241 | return -EPERM; | |
242 | ||
b96fc541 | 243 | rc = nvmem_reg_read(nvmem, pos, buf, count); |
84400305 SK |
244 | |
245 | if (rc) | |
246 | return rc; | |
247 | ||
248 | return count; | |
249 | } | |
250 | ||
251 | static ssize_t bin_attr_nvmem_write(struct file *filp, struct kobject *kobj, | |
252 | struct bin_attribute *attr, char *buf, | |
253 | loff_t pos, size_t count) | |
254 | { | |
255 | struct device *dev; | |
256 | struct nvmem_device *nvmem; | |
257 | int rc; | |
258 | ||
259 | if (attr->private) | |
260 | dev = attr->private; | |
261 | else | |
28371cc6 | 262 | dev = kobj_to_dev(kobj); |
84400305 SK |
263 | nvmem = to_nvmem_device(dev); |
264 | ||
265 | /* Stop the user from writing */ | |
266 | if (pos >= nvmem->size) | |
267 | return -EFBIG; | |
268 | ||
83566715 DA |
269 | if (!IS_ALIGNED(pos, nvmem->stride)) |
270 | return -EINVAL; | |
271 | ||
84400305 SK |
272 | if (count < nvmem->word_size) |
273 | return -EINVAL; | |
274 | ||
275 | if (pos + count > nvmem->size) | |
276 | count = nvmem->size - pos; | |
277 | ||
278 | count = round_down(count, nvmem->word_size); | |
279 | ||
280 | if (!nvmem->reg_write) | |
281 | return -EPERM; | |
282 | ||
b96fc541 | 283 | rc = nvmem_reg_write(nvmem, pos, buf, count); |
84400305 SK |
284 | |
285 | if (rc) | |
286 | return rc; | |
287 | ||
288 | return count; | |
289 | } | |
290 | ||
2a4542e5 | 291 | static umode_t nvmem_bin_attr_get_umode(struct nvmem_device *nvmem) |
84400305 | 292 | { |
84400305 SK |
293 | umode_t mode = 0400; |
294 | ||
295 | if (!nvmem->root_only) | |
296 | mode |= 0044; | |
297 | ||
298 | if (!nvmem->read_only) | |
299 | mode |= 0200; | |
300 | ||
301 | if (!nvmem->reg_write) | |
302 | mode &= ~0200; | |
303 | ||
304 | if (!nvmem->reg_read) | |
305 | mode &= ~0444; | |
306 | ||
307 | return mode; | |
308 | } | |
309 | ||
2a4542e5 SK |
310 | static umode_t nvmem_bin_attr_is_visible(struct kobject *kobj, |
311 | struct bin_attribute *attr, int i) | |
312 | { | |
28371cc6 | 313 | struct device *dev = kobj_to_dev(kobj); |
2a4542e5 SK |
314 | struct nvmem_device *nvmem = to_nvmem_device(dev); |
315 | ||
86192251 SK |
316 | attr->size = nvmem->size; |
317 | ||
2a4542e5 SK |
318 | return nvmem_bin_attr_get_umode(nvmem); |
319 | } | |
320 | ||
84400305 SK |
321 | /* default read/write permissions */ |
322 | static struct bin_attribute bin_attr_rw_nvmem = { | |
323 | .attr = { | |
324 | .name = "nvmem", | |
325 | .mode = 0644, | |
326 | }, | |
327 | .read = bin_attr_nvmem_read, | |
328 | .write = bin_attr_nvmem_write, | |
329 | }; | |
330 | ||
331 | static struct bin_attribute *nvmem_bin_attributes[] = { | |
332 | &bin_attr_rw_nvmem, | |
333 | NULL, | |
334 | }; | |
335 | ||
336 | static const struct attribute_group nvmem_bin_group = { | |
337 | .bin_attrs = nvmem_bin_attributes, | |
338 | .attrs = nvmem_attrs, | |
339 | .is_bin_visible = nvmem_bin_attr_is_visible, | |
340 | }; | |
341 | ||
342 | static const struct attribute_group *nvmem_dev_groups[] = { | |
343 | &nvmem_bin_group, | |
344 | NULL, | |
345 | }; | |
346 | ||
2a4542e5 | 347 | static struct bin_attribute bin_attr_nvmem_eeprom_compat = { |
84400305 | 348 | .attr = { |
2a4542e5 | 349 | .name = "eeprom", |
84400305 SK |
350 | }, |
351 | .read = bin_attr_nvmem_read, | |
352 | .write = bin_attr_nvmem_write, | |
353 | }; | |
354 | ||
84400305 SK |
355 | /* |
356 | * nvmem_setup_compat() - Create an additional binary entry in | |
357 | * drivers sys directory, to be backwards compatible with the older | |
358 | * drivers/misc/eeprom drivers. | |
359 | */ | |
360 | static int nvmem_sysfs_setup_compat(struct nvmem_device *nvmem, | |
361 | const struct nvmem_config *config) | |
362 | { | |
363 | int rval; | |
364 | ||
365 | if (!config->compat) | |
366 | return 0; | |
367 | ||
368 | if (!config->base_dev) | |
369 | return -EINVAL; | |
370 | ||
fd307a4a JP |
371 | if (config->type == NVMEM_TYPE_FRAM) |
372 | bin_attr_nvmem_eeprom_compat.attr.name = "fram"; | |
373 | ||
2a4542e5 SK |
374 | nvmem->eeprom = bin_attr_nvmem_eeprom_compat; |
375 | nvmem->eeprom.attr.mode = nvmem_bin_attr_get_umode(nvmem); | |
84400305 SK |
376 | nvmem->eeprom.size = nvmem->size; |
377 | #ifdef CONFIG_DEBUG_LOCK_ALLOC | |
378 | nvmem->eeprom.attr.key = &eeprom_lock_key; | |
379 | #endif | |
380 | nvmem->eeprom.private = &nvmem->dev; | |
381 | nvmem->base_dev = config->base_dev; | |
382 | ||
383 | rval = device_create_bin_file(nvmem->base_dev, &nvmem->eeprom); | |
384 | if (rval) { | |
385 | dev_err(&nvmem->dev, | |
386 | "Failed to create eeprom binary file %d\n", rval); | |
387 | return rval; | |
388 | } | |
389 | ||
390 | nvmem->flags |= FLAG_COMPAT; | |
391 | ||
392 | return 0; | |
393 | } | |
394 | ||
395 | static void nvmem_sysfs_remove_compat(struct nvmem_device *nvmem, | |
396 | const struct nvmem_config *config) | |
397 | { | |
398 | if (config->compat) | |
399 | device_remove_bin_file(nvmem->base_dev, &nvmem->eeprom); | |
400 | } | |
401 | ||
402 | #else /* CONFIG_NVMEM_SYSFS */ | |
403 | ||
404 | static int nvmem_sysfs_setup_compat(struct nvmem_device *nvmem, | |
405 | const struct nvmem_config *config) | |
406 | { | |
407 | return -ENOSYS; | |
408 | } | |
409 | static void nvmem_sysfs_remove_compat(struct nvmem_device *nvmem, | |
410 | const struct nvmem_config *config) | |
411 | { | |
412 | } | |
413 | ||
414 | #endif /* CONFIG_NVMEM_SYSFS */ | |
b6c217ab | 415 | |
eace75cf SK |
416 | static void nvmem_release(struct device *dev) |
417 | { | |
418 | struct nvmem_device *nvmem = to_nvmem_device(dev); | |
419 | ||
1eb51d6a | 420 | ida_free(&nvmem_ida, nvmem->id); |
a9c3766c | 421 | gpiod_put(nvmem->wp_gpio); |
eace75cf SK |
422 | kfree(nvmem); |
423 | } | |
424 | ||
425 | static const struct device_type nvmem_provider_type = { | |
426 | .release = nvmem_release, | |
427 | }; | |
428 | ||
429 | static struct bus_type nvmem_bus_type = { | |
430 | .name = "nvmem", | |
431 | }; | |
432 | ||
7ae6478b | 433 | static void nvmem_cell_entry_drop(struct nvmem_cell_entry *cell) |
eace75cf | 434 | { |
bee1138b | 435 | blocking_notifier_call_chain(&nvmem_notifier, NVMEM_CELL_REMOVE, cell); |
c7235ee3 | 436 | mutex_lock(&nvmem_mutex); |
eace75cf | 437 | list_del(&cell->node); |
c7235ee3 | 438 | mutex_unlock(&nvmem_mutex); |
0749aa25 | 439 | of_node_put(cell->np); |
16bb7abc | 440 | kfree_const(cell->name); |
eace75cf SK |
441 | kfree(cell); |
442 | } | |
443 | ||
444 | static void nvmem_device_remove_all_cells(const struct nvmem_device *nvmem) | |
445 | { | |
7ae6478b | 446 | struct nvmem_cell_entry *cell, *p; |
eace75cf | 447 | |
c7235ee3 | 448 | list_for_each_entry_safe(cell, p, &nvmem->cells, node) |
7ae6478b | 449 | nvmem_cell_entry_drop(cell); |
eace75cf SK |
450 | } |
451 | ||
7ae6478b | 452 | static void nvmem_cell_entry_add(struct nvmem_cell_entry *cell) |
eace75cf | 453 | { |
c7235ee3 BG |
454 | mutex_lock(&nvmem_mutex); |
455 | list_add_tail(&cell->node, &cell->nvmem->cells); | |
456 | mutex_unlock(&nvmem_mutex); | |
bee1138b | 457 | blocking_notifier_call_chain(&nvmem_notifier, NVMEM_CELL_ADD, cell); |
eace75cf SK |
458 | } |
459 | ||
7ae6478b SK |
460 | static int nvmem_cell_info_to_nvmem_cell_entry_nodup(struct nvmem_device *nvmem, |
461 | const struct nvmem_cell_info *info, | |
462 | struct nvmem_cell_entry *cell) | |
eace75cf SK |
463 | { |
464 | cell->nvmem = nvmem; | |
465 | cell->offset = info->offset; | |
466 | cell->bytes = info->bytes; | |
fc9eec4d | 467 | cell->name = info->name; |
eace75cf SK |
468 | |
469 | cell->bit_offset = info->bit_offset; | |
470 | cell->nbits = info->nbits; | |
dbc2f620 | 471 | cell->np = info->np; |
eace75cf SK |
472 | |
473 | if (cell->nbits) | |
474 | cell->bytes = DIV_ROUND_UP(cell->nbits + cell->bit_offset, | |
475 | BITS_PER_BYTE); | |
476 | ||
477 | if (!IS_ALIGNED(cell->offset, nvmem->stride)) { | |
478 | dev_err(&nvmem->dev, | |
479 | "cell %s unaligned to nvmem stride %d\n", | |
fc9eec4d | 480 | cell->name ?: "<unknown>", nvmem->stride); |
eace75cf SK |
481 | return -EINVAL; |
482 | } | |
483 | ||
484 | return 0; | |
485 | } | |
486 | ||
7ae6478b SK |
487 | static int nvmem_cell_info_to_nvmem_cell_entry(struct nvmem_device *nvmem, |
488 | const struct nvmem_cell_info *info, | |
489 | struct nvmem_cell_entry *cell) | |
fc9eec4d VK |
490 | { |
491 | int err; | |
492 | ||
7ae6478b | 493 | err = nvmem_cell_info_to_nvmem_cell_entry_nodup(nvmem, info, cell); |
fc9eec4d VK |
494 | if (err) |
495 | return err; | |
496 | ||
497 | cell->name = kstrdup_const(info->name, GFP_KERNEL); | |
498 | if (!cell->name) | |
499 | return -ENOMEM; | |
500 | ||
501 | return 0; | |
502 | } | |
503 | ||
2ded6830 MW |
504 | /** |
505 | * nvmem_add_one_cell() - Add one cell information to an nvmem device | |
506 | * | |
507 | * @nvmem: nvmem device to add cells to. | |
508 | * @info: nvmem cell info to add to the device | |
509 | * | |
510 | * Return: 0 or negative error code on failure. | |
511 | */ | |
512 | int nvmem_add_one_cell(struct nvmem_device *nvmem, | |
513 | const struct nvmem_cell_info *info) | |
514 | { | |
515 | struct nvmem_cell_entry *cell; | |
516 | int rval; | |
517 | ||
518 | cell = kzalloc(sizeof(*cell), GFP_KERNEL); | |
519 | if (!cell) | |
520 | return -ENOMEM; | |
521 | ||
522 | rval = nvmem_cell_info_to_nvmem_cell_entry(nvmem, info, cell); | |
523 | if (rval) { | |
524 | kfree(cell); | |
525 | return rval; | |
526 | } | |
527 | ||
528 | nvmem_cell_entry_add(cell); | |
529 | ||
530 | return 0; | |
531 | } | |
532 | EXPORT_SYMBOL_GPL(nvmem_add_one_cell); | |
533 | ||
b3db17e4 AL |
534 | /** |
535 | * nvmem_add_cells() - Add cell information to an nvmem device | |
536 | * | |
537 | * @nvmem: nvmem device to add cells to. | |
538 | * @info: nvmem cell info to add to the device | |
539 | * @ncells: number of cells in info | |
540 | * | |
541 | * Return: 0 or negative error code on failure. | |
542 | */ | |
ef92ab30 | 543 | static int nvmem_add_cells(struct nvmem_device *nvmem, |
b3db17e4 AL |
544 | const struct nvmem_cell_info *info, |
545 | int ncells) | |
eace75cf | 546 | { |
2ded6830 | 547 | int i, rval; |
eace75cf | 548 | |
b3db17e4 | 549 | for (i = 0; i < ncells; i++) { |
2ded6830 MW |
550 | rval = nvmem_add_one_cell(nvmem, &info[i]); |
551 | if (rval) | |
552 | return rval; | |
eace75cf SK |
553 | } |
554 | ||
2ded6830 | 555 | return 0; |
eace75cf SK |
556 | } |
557 | ||
bee1138b BG |
558 | /** |
559 | * nvmem_register_notifier() - Register a notifier block for nvmem events. | |
560 | * | |
561 | * @nb: notifier block to be called on nvmem events. | |
562 | * | |
563 | * Return: 0 on success, negative error number on failure. | |
564 | */ | |
565 | int nvmem_register_notifier(struct notifier_block *nb) | |
566 | { | |
567 | return blocking_notifier_chain_register(&nvmem_notifier, nb); | |
568 | } | |
569 | EXPORT_SYMBOL_GPL(nvmem_register_notifier); | |
570 | ||
571 | /** | |
572 | * nvmem_unregister_notifier() - Unregister a notifier block for nvmem events. | |
573 | * | |
574 | * @nb: notifier block to be unregistered. | |
575 | * | |
576 | * Return: 0 on success, negative error number on failure. | |
577 | */ | |
578 | int nvmem_unregister_notifier(struct notifier_block *nb) | |
579 | { | |
580 | return blocking_notifier_chain_unregister(&nvmem_notifier, nb); | |
581 | } | |
582 | EXPORT_SYMBOL_GPL(nvmem_unregister_notifier); | |
583 | ||
b985f4cb BG |
584 | static int nvmem_add_cells_from_table(struct nvmem_device *nvmem) |
585 | { | |
586 | const struct nvmem_cell_info *info; | |
587 | struct nvmem_cell_table *table; | |
7ae6478b | 588 | struct nvmem_cell_entry *cell; |
b985f4cb BG |
589 | int rval = 0, i; |
590 | ||
591 | mutex_lock(&nvmem_cell_mutex); | |
592 | list_for_each_entry(table, &nvmem_cell_tables, node) { | |
593 | if (strcmp(nvmem_dev_name(nvmem), table->nvmem_name) == 0) { | |
594 | for (i = 0; i < table->ncells; i++) { | |
595 | info = &table->cells[i]; | |
596 | ||
597 | cell = kzalloc(sizeof(*cell), GFP_KERNEL); | |
598 | if (!cell) { | |
599 | rval = -ENOMEM; | |
600 | goto out; | |
601 | } | |
602 | ||
7ae6478b | 603 | rval = nvmem_cell_info_to_nvmem_cell_entry(nvmem, info, cell); |
b985f4cb BG |
604 | if (rval) { |
605 | kfree(cell); | |
606 | goto out; | |
607 | } | |
608 | ||
7ae6478b | 609 | nvmem_cell_entry_add(cell); |
b985f4cb BG |
610 | } |
611 | } | |
612 | } | |
613 | ||
614 | out: | |
615 | mutex_unlock(&nvmem_cell_mutex); | |
616 | return rval; | |
617 | } | |
618 | ||
7ae6478b SK |
619 | static struct nvmem_cell_entry * |
620 | nvmem_find_cell_entry_by_name(struct nvmem_device *nvmem, const char *cell_id) | |
506157be | 621 | { |
7ae6478b | 622 | struct nvmem_cell_entry *iter, *cell = NULL; |
506157be BG |
623 | |
624 | mutex_lock(&nvmem_mutex); | |
1c832674 AB |
625 | list_for_each_entry(iter, &nvmem->cells, node) { |
626 | if (strcmp(cell_id, iter->name) == 0) { | |
627 | cell = iter; | |
506157be | 628 | break; |
1c832674 | 629 | } |
506157be BG |
630 | } |
631 | mutex_unlock(&nvmem_mutex); | |
632 | ||
633 | return cell; | |
634 | } | |
635 | ||
fd3bb8f5 EG |
636 | static int nvmem_validate_keepouts(struct nvmem_device *nvmem) |
637 | { | |
638 | unsigned int cur = 0; | |
639 | const struct nvmem_keepout *keepout = nvmem->keepout; | |
640 | const struct nvmem_keepout *keepoutend = keepout + nvmem->nkeepout; | |
641 | ||
642 | while (keepout < keepoutend) { | |
643 | /* Ensure keepouts are sorted and don't overlap. */ | |
644 | if (keepout->start < cur) { | |
645 | dev_err(&nvmem->dev, | |
646 | "Keepout regions aren't sorted or overlap.\n"); | |
647 | ||
648 | return -ERANGE; | |
649 | } | |
650 | ||
651 | if (keepout->end < keepout->start) { | |
652 | dev_err(&nvmem->dev, | |
653 | "Invalid keepout region.\n"); | |
654 | ||
655 | return -EINVAL; | |
656 | } | |
657 | ||
658 | /* | |
659 | * Validate keepouts (and holes between) don't violate | |
660 | * word_size constraints. | |
661 | */ | |
662 | if ((keepout->end - keepout->start < nvmem->word_size) || | |
663 | ((keepout->start != cur) && | |
664 | (keepout->start - cur < nvmem->word_size))) { | |
665 | ||
666 | dev_err(&nvmem->dev, | |
667 | "Keepout regions violate word_size constraints.\n"); | |
668 | ||
669 | return -ERANGE; | |
670 | } | |
671 | ||
672 | /* Validate keepouts don't violate stride (alignment). */ | |
673 | if (!IS_ALIGNED(keepout->start, nvmem->stride) || | |
674 | !IS_ALIGNED(keepout->end, nvmem->stride)) { | |
675 | ||
676 | dev_err(&nvmem->dev, | |
677 | "Keepout regions violate stride.\n"); | |
678 | ||
679 | return -EINVAL; | |
680 | } | |
681 | ||
682 | cur = keepout->end; | |
683 | keepout++; | |
684 | } | |
685 | ||
686 | return 0; | |
687 | } | |
688 | ||
e888d445 BG |
689 | static int nvmem_add_cells_from_of(struct nvmem_device *nvmem) |
690 | { | |
e888d445 | 691 | struct device *dev = &nvmem->dev; |
50014d65 | 692 | struct device_node *child; |
e888d445 | 693 | const __be32 *addr; |
50014d65 | 694 | int len, ret; |
e888d445 | 695 | |
50014d65 MW |
696 | for_each_child_of_node(dev->of_node, child) { |
697 | struct nvmem_cell_info info = {0}; | |
e888d445 | 698 | |
e888d445 | 699 | addr = of_get_property(child, "reg", &len); |
0445efac AF |
700 | if (!addr) |
701 | continue; | |
702 | if (len < 2 * sizeof(u32)) { | |
e888d445 | 703 | dev_err(dev, "nvmem: invalid reg on %pOF\n", child); |
63879e29 | 704 | of_node_put(child); |
e888d445 BG |
705 | return -EINVAL; |
706 | } | |
707 | ||
50014d65 MW |
708 | info.offset = be32_to_cpup(addr++); |
709 | info.bytes = be32_to_cpup(addr); | |
710 | info.name = kasprintf(GFP_KERNEL, "%pOFn", child); | |
e888d445 BG |
711 | |
712 | addr = of_get_property(child, "bits", &len); | |
713 | if (addr && len == (2 * sizeof(u32))) { | |
50014d65 MW |
714 | info.bit_offset = be32_to_cpup(addr++); |
715 | info.nbits = be32_to_cpup(addr); | |
e888d445 BG |
716 | } |
717 | ||
50014d65 MW |
718 | info.np = of_node_get(child); |
719 | ||
720 | ret = nvmem_add_one_cell(nvmem, &info); | |
721 | kfree(info.name); | |
722 | if (ret) { | |
63879e29 | 723 | of_node_put(child); |
50014d65 | 724 | return ret; |
e888d445 | 725 | } |
e888d445 BG |
726 | } |
727 | ||
728 | return 0; | |
729 | } | |
730 | ||
eace75cf SK |
731 | /** |
732 | * nvmem_register() - Register a nvmem device for given nvmem_config. | |
3a758071 | 733 | * Also creates a binary entry in /sys/bus/nvmem/devices/dev-name/nvmem |
eace75cf SK |
734 | * |
735 | * @config: nvmem device configuration with which nvmem device is created. | |
736 | * | |
737 | * Return: Will be an ERR_PTR() on error or a valid pointer to nvmem_device | |
738 | * on success. | |
739 | */ | |
740 | ||
741 | struct nvmem_device *nvmem_register(const struct nvmem_config *config) | |
742 | { | |
743 | struct nvmem_device *nvmem; | |
eace75cf SK |
744 | int rval; |
745 | ||
746 | if (!config->dev) | |
747 | return ERR_PTR(-EINVAL); | |
748 | ||
061a320b SK |
749 | if (!config->reg_read && !config->reg_write) |
750 | return ERR_PTR(-EINVAL); | |
751 | ||
eace75cf SK |
752 | nvmem = kzalloc(sizeof(*nvmem), GFP_KERNEL); |
753 | if (!nvmem) | |
754 | return ERR_PTR(-ENOMEM); | |
755 | ||
2e8dc541 | 756 | rval = ida_alloc(&nvmem_ida, GFP_KERNEL); |
eace75cf SK |
757 | if (rval < 0) { |
758 | kfree(nvmem); | |
759 | return ERR_PTR(rval); | |
760 | } | |
31c6ff51 | 761 | |
3bd747c7 RKO |
762 | nvmem->id = rval; |
763 | ||
560181d3 RKO |
764 | nvmem->dev.type = &nvmem_provider_type; |
765 | nvmem->dev.bus = &nvmem_bus_type; | |
766 | nvmem->dev.parent = config->dev; | |
767 | ||
768 | device_initialize(&nvmem->dev); | |
769 | ||
569653f0 | 770 | if (!config->ignore_wp) |
2a127da4 KT |
771 | nvmem->wp_gpio = gpiod_get_optional(config->dev, "wp", |
772 | GPIOD_OUT_HIGH); | |
f7d8d7dc | 773 | if (IS_ERR(nvmem->wp_gpio)) { |
f7d8d7dc | 774 | rval = PTR_ERR(nvmem->wp_gpio); |
0c4862b1 | 775 | nvmem->wp_gpio = NULL; |
560181d3 | 776 | goto err_put_device; |
f7d8d7dc | 777 | } |
2a127da4 | 778 | |
c1de7f43 | 779 | kref_init(&nvmem->refcnt); |
c7235ee3 | 780 | INIT_LIST_HEAD(&nvmem->cells); |
c1de7f43 | 781 | |
eace75cf | 782 | nvmem->owner = config->owner; |
17eb18d6 MY |
783 | if (!nvmem->owner && config->dev->driver) |
784 | nvmem->owner = config->dev->driver->owner; | |
99897efd HK |
785 | nvmem->stride = config->stride ?: 1; |
786 | nvmem->word_size = config->word_size ?: 1; | |
795ddd18 | 787 | nvmem->size = config->size; |
e6de179d | 788 | nvmem->root_only = config->root_only; |
795ddd18 | 789 | nvmem->priv = config->priv; |
16688453 | 790 | nvmem->type = config->type; |
795ddd18 SK |
791 | nvmem->reg_read = config->reg_read; |
792 | nvmem->reg_write = config->reg_write; | |
5008062f | 793 | nvmem->cell_post_process = config->cell_post_process; |
fd3bb8f5 EG |
794 | nvmem->keepout = config->keepout; |
795 | nvmem->nkeepout = config->nkeepout; | |
1333a677 MW |
796 | if (config->of_node) |
797 | nvmem->dev.of_node = config->of_node; | |
798 | else if (!config->no_of_node) | |
517f14d9 | 799 | nvmem->dev.of_node = config->dev->of_node; |
fd0f4906 | 800 | |
731aa3fa SK |
801 | switch (config->id) { |
802 | case NVMEM_DEVID_NONE: | |
5544e90c | 803 | rval = dev_set_name(&nvmem->dev, "%s", config->name); |
731aa3fa SK |
804 | break; |
805 | case NVMEM_DEVID_AUTO: | |
5544e90c | 806 | rval = dev_set_name(&nvmem->dev, "%s%d", config->name, nvmem->id); |
731aa3fa SK |
807 | break; |
808 | default: | |
5544e90c | 809 | rval = dev_set_name(&nvmem->dev, "%s%d", |
fd0f4906 AS |
810 | config->name ? : "nvmem", |
811 | config->name ? config->id : nvmem->id); | |
731aa3fa | 812 | break; |
fd0f4906 | 813 | } |
eace75cf | 814 | |
560181d3 RKO |
815 | if (rval) |
816 | goto err_put_device; | |
5544e90c | 817 | |
1716cfe8 AB |
818 | nvmem->read_only = device_property_present(config->dev, "read-only") || |
819 | config->read_only || !nvmem->reg_write; | |
eace75cf | 820 | |
84400305 SK |
821 | #ifdef CONFIG_NVMEM_SYSFS |
822 | nvmem->dev.groups = nvmem_dev_groups; | |
823 | #endif | |
eace75cf | 824 | |
bd124456 GC |
825 | if (nvmem->nkeepout) { |
826 | rval = nvmem_validate_keepouts(nvmem); | |
827 | if (rval) | |
ab3428cf | 828 | goto err_put_device; |
bd124456 GC |
829 | } |
830 | ||
b6c217ab | 831 | if (config->compat) { |
ae0c2d72 | 832 | rval = nvmem_sysfs_setup_compat(nvmem, config); |
b6c217ab | 833 | if (rval) |
ab3428cf | 834 | goto err_put_device; |
eace75cf SK |
835 | } |
836 | ||
fa72d847 BG |
837 | if (config->cells) { |
838 | rval = nvmem_add_cells(nvmem, config->cells, config->ncells); | |
839 | if (rval) | |
db3546d5 | 840 | goto err_remove_cells; |
fa72d847 | 841 | } |
eace75cf | 842 | |
b985f4cb BG |
843 | rval = nvmem_add_cells_from_table(nvmem); |
844 | if (rval) | |
845 | goto err_remove_cells; | |
846 | ||
e888d445 BG |
847 | rval = nvmem_add_cells_from_of(nvmem); |
848 | if (rval) | |
849 | goto err_remove_cells; | |
850 | ||
ab3428cf RKO |
851 | dev_dbg(&nvmem->dev, "Registering nvmem device %s\n", config->name); |
852 | ||
853 | rval = device_add(&nvmem->dev); | |
854 | if (rval) | |
855 | goto err_remove_cells; | |
856 | ||
f4853e1c | 857 | blocking_notifier_call_chain(&nvmem_notifier, NVMEM_ADD, nvmem); |
bee1138b | 858 | |
eace75cf | 859 | return nvmem; |
3360acdf | 860 | |
b985f4cb BG |
861 | err_remove_cells: |
862 | nvmem_device_remove_all_cells(nvmem); | |
fa72d847 | 863 | if (config->compat) |
ae0c2d72 | 864 | nvmem_sysfs_remove_compat(nvmem, config); |
3360acdf JH |
865 | err_put_device: |
866 | put_device(&nvmem->dev); | |
867 | ||
b6c217ab | 868 | return ERR_PTR(rval); |
eace75cf SK |
869 | } |
870 | EXPORT_SYMBOL_GPL(nvmem_register); | |
871 | ||
c1de7f43 BG |
872 | static void nvmem_device_release(struct kref *kref) |
873 | { | |
874 | struct nvmem_device *nvmem; | |
875 | ||
876 | nvmem = container_of(kref, struct nvmem_device, refcnt); | |
877 | ||
bee1138b BG |
878 | blocking_notifier_call_chain(&nvmem_notifier, NVMEM_REMOVE, nvmem); |
879 | ||
c1de7f43 BG |
880 | if (nvmem->flags & FLAG_COMPAT) |
881 | device_remove_bin_file(nvmem->base_dev, &nvmem->eeprom); | |
882 | ||
883 | nvmem_device_remove_all_cells(nvmem); | |
f60442dd | 884 | device_unregister(&nvmem->dev); |
c1de7f43 BG |
885 | } |
886 | ||
eace75cf SK |
887 | /** |
888 | * nvmem_unregister() - Unregister previously registered nvmem device | |
889 | * | |
890 | * @nvmem: Pointer to previously registered nvmem device. | |
eace75cf | 891 | */ |
bf58e882 | 892 | void nvmem_unregister(struct nvmem_device *nvmem) |
eace75cf | 893 | { |
8c751e0d AS |
894 | if (nvmem) |
895 | kref_put(&nvmem->refcnt, nvmem_device_release); | |
eace75cf SK |
896 | } |
897 | EXPORT_SYMBOL_GPL(nvmem_unregister); | |
898 | ||
5825b2c6 | 899 | static void devm_nvmem_unregister(void *nvmem) |
f1f50eca | 900 | { |
5825b2c6 | 901 | nvmem_unregister(nvmem); |
f1f50eca AS |
902 | } |
903 | ||
904 | /** | |
905 | * devm_nvmem_register() - Register a managed nvmem device for given | |
906 | * nvmem_config. | |
3a758071 | 907 | * Also creates a binary entry in /sys/bus/nvmem/devices/dev-name/nvmem |
f1f50eca | 908 | * |
b378c779 | 909 | * @dev: Device that uses the nvmem device. |
f1f50eca AS |
910 | * @config: nvmem device configuration with which nvmem device is created. |
911 | * | |
912 | * Return: Will be an ERR_PTR() on error or a valid pointer to nvmem_device | |
913 | * on success. | |
914 | */ | |
915 | struct nvmem_device *devm_nvmem_register(struct device *dev, | |
916 | const struct nvmem_config *config) | |
917 | { | |
5825b2c6 AS |
918 | struct nvmem_device *nvmem; |
919 | int ret; | |
f1f50eca AS |
920 | |
921 | nvmem = nvmem_register(config); | |
5825b2c6 AS |
922 | if (IS_ERR(nvmem)) |
923 | return nvmem; | |
f1f50eca | 924 | |
5825b2c6 AS |
925 | ret = devm_add_action_or_reset(dev, devm_nvmem_unregister, nvmem); |
926 | if (ret) | |
927 | return ERR_PTR(ret); | |
f1f50eca AS |
928 | |
929 | return nvmem; | |
930 | } | |
931 | EXPORT_SYMBOL_GPL(devm_nvmem_register); | |
932 | ||
8c2a2b8c TB |
933 | static struct nvmem_device *__nvmem_device_get(void *data, |
934 | int (*match)(struct device *dev, const void *data)) | |
69aba794 SK |
935 | { |
936 | struct nvmem_device *nvmem = NULL; | |
8c2a2b8c | 937 | struct device *dev; |
69aba794 | 938 | |
c7235ee3 | 939 | mutex_lock(&nvmem_mutex); |
8c2a2b8c TB |
940 | dev = bus_find_device(&nvmem_bus_type, NULL, data, match); |
941 | if (dev) | |
942 | nvmem = to_nvmem_device(dev); | |
69aba794 | 943 | mutex_unlock(&nvmem_mutex); |
c7235ee3 BG |
944 | if (!nvmem) |
945 | return ERR_PTR(-EPROBE_DEFER); | |
69aba794 SK |
946 | |
947 | if (!try_module_get(nvmem->owner)) { | |
948 | dev_err(&nvmem->dev, | |
949 | "could not increase module refcount for cell %s\n", | |
5db652c9 | 950 | nvmem_dev_name(nvmem)); |
69aba794 | 951 | |
73e9dc4d | 952 | put_device(&nvmem->dev); |
69aba794 SK |
953 | return ERR_PTR(-EINVAL); |
954 | } | |
955 | ||
c1de7f43 BG |
956 | kref_get(&nvmem->refcnt); |
957 | ||
69aba794 SK |
958 | return nvmem; |
959 | } | |
960 | ||
961 | static void __nvmem_device_put(struct nvmem_device *nvmem) | |
962 | { | |
73e9dc4d | 963 | put_device(&nvmem->dev); |
69aba794 | 964 | module_put(nvmem->owner); |
c1de7f43 | 965 | kref_put(&nvmem->refcnt, nvmem_device_release); |
69aba794 SK |
966 | } |
967 | ||
e701c67c | 968 | #if IS_ENABLED(CONFIG_OF) |
e2a5402e SK |
969 | /** |
970 | * of_nvmem_device_get() - Get nvmem device from a given id | |
971 | * | |
29143268 | 972 | * @np: Device tree node that uses the nvmem device. |
e2a5402e SK |
973 | * @id: nvmem name from nvmem-names property. |
974 | * | |
975 | * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_device | |
976 | * on success. | |
977 | */ | |
978 | struct nvmem_device *of_nvmem_device_get(struct device_node *np, const char *id) | |
979 | { | |
980 | ||
981 | struct device_node *nvmem_np; | |
b1c194dc | 982 | struct nvmem_device *nvmem; |
d4e7fef1 | 983 | int index = 0; |
e2a5402e | 984 | |
d4e7fef1 AB |
985 | if (id) |
986 | index = of_property_match_string(np, "nvmem-names", id); | |
e2a5402e SK |
987 | |
988 | nvmem_np = of_parse_phandle(np, "nvmem", index); | |
989 | if (!nvmem_np) | |
d4e7fef1 | 990 | return ERR_PTR(-ENOENT); |
e2a5402e | 991 | |
b1c194dc VK |
992 | nvmem = __nvmem_device_get(nvmem_np, device_match_of_node); |
993 | of_node_put(nvmem_np); | |
994 | return nvmem; | |
e2a5402e SK |
995 | } |
996 | EXPORT_SYMBOL_GPL(of_nvmem_device_get); | |
997 | #endif | |
998 | ||
999 | /** | |
1000 | * nvmem_device_get() - Get nvmem device from a given id | |
1001 | * | |
29143268 VG |
1002 | * @dev: Device that uses the nvmem device. |
1003 | * @dev_name: name of the requested nvmem device. | |
e2a5402e SK |
1004 | * |
1005 | * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_device | |
1006 | * on success. | |
1007 | */ | |
1008 | struct nvmem_device *nvmem_device_get(struct device *dev, const char *dev_name) | |
1009 | { | |
1010 | if (dev->of_node) { /* try dt first */ | |
1011 | struct nvmem_device *nvmem; | |
1012 | ||
1013 | nvmem = of_nvmem_device_get(dev->of_node, dev_name); | |
1014 | ||
1015 | if (!IS_ERR(nvmem) || PTR_ERR(nvmem) == -EPROBE_DEFER) | |
1016 | return nvmem; | |
1017 | ||
1018 | } | |
1019 | ||
8c2a2b8c | 1020 | return __nvmem_device_get((void *)dev_name, device_match_name); |
e2a5402e SK |
1021 | } |
1022 | EXPORT_SYMBOL_GPL(nvmem_device_get); | |
1023 | ||
8c2a2b8c TB |
1024 | /** |
1025 | * nvmem_device_find() - Find nvmem device with matching function | |
1026 | * | |
1027 | * @data: Data to pass to match function | |
1028 | * @match: Callback function to check device | |
1029 | * | |
1030 | * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_device | |
1031 | * on success. | |
1032 | */ | |
1033 | struct nvmem_device *nvmem_device_find(void *data, | |
1034 | int (*match)(struct device *dev, const void *data)) | |
1035 | { | |
1036 | return __nvmem_device_get(data, match); | |
1037 | } | |
1038 | EXPORT_SYMBOL_GPL(nvmem_device_find); | |
1039 | ||
e2a5402e SK |
1040 | static int devm_nvmem_device_match(struct device *dev, void *res, void *data) |
1041 | { | |
1042 | struct nvmem_device **nvmem = res; | |
1043 | ||
1044 | if (WARN_ON(!nvmem || !*nvmem)) | |
1045 | return 0; | |
1046 | ||
1047 | return *nvmem == data; | |
1048 | } | |
1049 | ||
1050 | static void devm_nvmem_device_release(struct device *dev, void *res) | |
1051 | { | |
1052 | nvmem_device_put(*(struct nvmem_device **)res); | |
1053 | } | |
1054 | ||
1055 | /** | |
1056 | * devm_nvmem_device_put() - put alredy got nvmem device | |
1057 | * | |
29143268 | 1058 | * @dev: Device that uses the nvmem device. |
e2a5402e SK |
1059 | * @nvmem: pointer to nvmem device allocated by devm_nvmem_cell_get(), |
1060 | * that needs to be released. | |
1061 | */ | |
1062 | void devm_nvmem_device_put(struct device *dev, struct nvmem_device *nvmem) | |
1063 | { | |
1064 | int ret; | |
1065 | ||
1066 | ret = devres_release(dev, devm_nvmem_device_release, | |
1067 | devm_nvmem_device_match, nvmem); | |
1068 | ||
1069 | WARN_ON(ret); | |
1070 | } | |
1071 | EXPORT_SYMBOL_GPL(devm_nvmem_device_put); | |
1072 | ||
1073 | /** | |
1074 | * nvmem_device_put() - put alredy got nvmem device | |
1075 | * | |
1076 | * @nvmem: pointer to nvmem device that needs to be released. | |
1077 | */ | |
1078 | void nvmem_device_put(struct nvmem_device *nvmem) | |
1079 | { | |
1080 | __nvmem_device_put(nvmem); | |
1081 | } | |
1082 | EXPORT_SYMBOL_GPL(nvmem_device_put); | |
1083 | ||
1084 | /** | |
1085 | * devm_nvmem_device_get() - Get nvmem cell of device form a given id | |
1086 | * | |
29143268 VG |
1087 | * @dev: Device that requests the nvmem device. |
1088 | * @id: name id for the requested nvmem device. | |
e2a5402e SK |
1089 | * |
1090 | * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_cell | |
1091 | * on success. The nvmem_cell will be freed by the automatically once the | |
1092 | * device is freed. | |
1093 | */ | |
1094 | struct nvmem_device *devm_nvmem_device_get(struct device *dev, const char *id) | |
1095 | { | |
1096 | struct nvmem_device **ptr, *nvmem; | |
1097 | ||
1098 | ptr = devres_alloc(devm_nvmem_device_release, sizeof(*ptr), GFP_KERNEL); | |
1099 | if (!ptr) | |
1100 | return ERR_PTR(-ENOMEM); | |
1101 | ||
1102 | nvmem = nvmem_device_get(dev, id); | |
1103 | if (!IS_ERR(nvmem)) { | |
1104 | *ptr = nvmem; | |
1105 | devres_add(dev, ptr); | |
1106 | } else { | |
1107 | devres_free(ptr); | |
1108 | } | |
1109 | ||
1110 | return nvmem; | |
1111 | } | |
1112 | EXPORT_SYMBOL_GPL(devm_nvmem_device_get); | |
1113 | ||
5d8e6e6c MW |
1114 | static struct nvmem_cell *nvmem_create_cell(struct nvmem_cell_entry *entry, |
1115 | const char *id, int index) | |
7ae6478b SK |
1116 | { |
1117 | struct nvmem_cell *cell; | |
1118 | const char *name = NULL; | |
1119 | ||
1120 | cell = kzalloc(sizeof(*cell), GFP_KERNEL); | |
1121 | if (!cell) | |
1122 | return ERR_PTR(-ENOMEM); | |
1123 | ||
1124 | if (id) { | |
1125 | name = kstrdup_const(id, GFP_KERNEL); | |
1126 | if (!name) { | |
1127 | kfree(cell); | |
1128 | return ERR_PTR(-ENOMEM); | |
1129 | } | |
1130 | } | |
1131 | ||
1132 | cell->id = name; | |
1133 | cell->entry = entry; | |
5d8e6e6c | 1134 | cell->index = index; |
7ae6478b SK |
1135 | |
1136 | return cell; | |
1137 | } | |
1138 | ||
506157be BG |
1139 | static struct nvmem_cell * |
1140 | nvmem_cell_get_from_lookup(struct device *dev, const char *con_id) | |
69aba794 | 1141 | { |
7ae6478b | 1142 | struct nvmem_cell_entry *cell_entry; |
506157be BG |
1143 | struct nvmem_cell *cell = ERR_PTR(-ENOENT); |
1144 | struct nvmem_cell_lookup *lookup; | |
69aba794 | 1145 | struct nvmem_device *nvmem; |
506157be | 1146 | const char *dev_id; |
69aba794 | 1147 | |
506157be BG |
1148 | if (!dev) |
1149 | return ERR_PTR(-EINVAL); | |
1150 | ||
1151 | dev_id = dev_name(dev); | |
1152 | ||
1153 | mutex_lock(&nvmem_lookup_mutex); | |
1154 | ||
1155 | list_for_each_entry(lookup, &nvmem_lookup_list, node) { | |
1156 | if ((strcmp(lookup->dev_id, dev_id) == 0) && | |
1157 | (strcmp(lookup->con_id, con_id) == 0)) { | |
1158 | /* This is the right entry. */ | |
8c2a2b8c TB |
1159 | nvmem = __nvmem_device_get((void *)lookup->nvmem_name, |
1160 | device_match_name); | |
cccb3b19 | 1161 | if (IS_ERR(nvmem)) { |
506157be | 1162 | /* Provider may not be registered yet. */ |
cccb3b19 | 1163 | cell = ERR_CAST(nvmem); |
9bfd8198 | 1164 | break; |
506157be BG |
1165 | } |
1166 | ||
7ae6478b SK |
1167 | cell_entry = nvmem_find_cell_entry_by_name(nvmem, |
1168 | lookup->cell_name); | |
1169 | if (!cell_entry) { | |
506157be | 1170 | __nvmem_device_put(nvmem); |
cccb3b19 | 1171 | cell = ERR_PTR(-ENOENT); |
7ae6478b | 1172 | } else { |
5d8e6e6c | 1173 | cell = nvmem_create_cell(cell_entry, con_id, 0); |
7ae6478b SK |
1174 | if (IS_ERR(cell)) |
1175 | __nvmem_device_put(nvmem); | |
506157be | 1176 | } |
9bfd8198 | 1177 | break; |
506157be BG |
1178 | } |
1179 | } | |
69aba794 | 1180 | |
506157be | 1181 | mutex_unlock(&nvmem_lookup_mutex); |
69aba794 SK |
1182 | return cell; |
1183 | } | |
1184 | ||
e701c67c | 1185 | #if IS_ENABLED(CONFIG_OF) |
7ae6478b SK |
1186 | static struct nvmem_cell_entry * |
1187 | nvmem_find_cell_entry_by_node(struct nvmem_device *nvmem, struct device_node *np) | |
3c53e235 | 1188 | { |
7ae6478b | 1189 | struct nvmem_cell_entry *iter, *cell = NULL; |
3c53e235 AB |
1190 | |
1191 | mutex_lock(&nvmem_mutex); | |
1c832674 AB |
1192 | list_for_each_entry(iter, &nvmem->cells, node) { |
1193 | if (np == iter->np) { | |
1194 | cell = iter; | |
3c53e235 | 1195 | break; |
1c832674 | 1196 | } |
3c53e235 AB |
1197 | } |
1198 | mutex_unlock(&nvmem_mutex); | |
1199 | ||
1200 | return cell; | |
1201 | } | |
1202 | ||
69aba794 SK |
1203 | /** |
1204 | * of_nvmem_cell_get() - Get a nvmem cell from given device node and cell id | |
1205 | * | |
29143268 | 1206 | * @np: Device tree node that uses the nvmem cell. |
165589f0 BG |
1207 | * @id: nvmem cell name from nvmem-cell-names property, or NULL |
1208 | * for the cell at index 0 (the lone cell with no accompanying | |
1209 | * nvmem-cell-names property). | |
69aba794 SK |
1210 | * |
1211 | * Return: Will be an ERR_PTR() on error or a valid pointer | |
1212 | * to a struct nvmem_cell. The nvmem_cell will be freed by the | |
1213 | * nvmem_cell_put(). | |
1214 | */ | |
165589f0 | 1215 | struct nvmem_cell *of_nvmem_cell_get(struct device_node *np, const char *id) |
69aba794 SK |
1216 | { |
1217 | struct device_node *cell_np, *nvmem_np; | |
69aba794 | 1218 | struct nvmem_device *nvmem; |
7ae6478b | 1219 | struct nvmem_cell_entry *cell_entry; |
e888d445 | 1220 | struct nvmem_cell *cell; |
5d8e6e6c | 1221 | struct of_phandle_args cell_spec; |
fd0c478c | 1222 | int index = 0; |
5d8e6e6c MW |
1223 | int cell_index = 0; |
1224 | int ret; | |
69aba794 | 1225 | |
fd0c478c | 1226 | /* if cell name exists, find index to the name */ |
165589f0 BG |
1227 | if (id) |
1228 | index = of_property_match_string(np, "nvmem-cell-names", id); | |
69aba794 | 1229 | |
5d8e6e6c MW |
1230 | ret = of_parse_phandle_with_optional_args(np, "nvmem-cells", |
1231 | "#nvmem-cell-cells", | |
1232 | index, &cell_spec); | |
1233 | if (ret) | |
06be6208 | 1234 | return ERR_PTR(-ENOENT); |
5d8e6e6c MW |
1235 | |
1236 | if (cell_spec.args_count > 1) | |
1237 | return ERR_PTR(-EINVAL); | |
1238 | ||
1239 | cell_np = cell_spec.np; | |
1240 | if (cell_spec.args_count) | |
1241 | cell_index = cell_spec.args[0]; | |
69aba794 | 1242 | |
edcf2fb6 MW |
1243 | nvmem_np = of_get_parent(cell_np); |
1244 | if (!nvmem_np) { | |
1245 | of_node_put(cell_np); | |
69aba794 | 1246 | return ERR_PTR(-EINVAL); |
edcf2fb6 | 1247 | } |
69aba794 | 1248 | |
8c2a2b8c | 1249 | nvmem = __nvmem_device_get(nvmem_np, device_match_of_node); |
aad8d097 | 1250 | of_node_put(nvmem_np); |
edcf2fb6 MW |
1251 | if (IS_ERR(nvmem)) { |
1252 | of_node_put(cell_np); | |
69aba794 | 1253 | return ERR_CAST(nvmem); |
edcf2fb6 | 1254 | } |
69aba794 | 1255 | |
7ae6478b | 1256 | cell_entry = nvmem_find_cell_entry_by_node(nvmem, cell_np); |
edcf2fb6 | 1257 | of_node_put(cell_np); |
7ae6478b | 1258 | if (!cell_entry) { |
e888d445 BG |
1259 | __nvmem_device_put(nvmem); |
1260 | return ERR_PTR(-ENOENT); | |
69aba794 SK |
1261 | } |
1262 | ||
5d8e6e6c | 1263 | cell = nvmem_create_cell(cell_entry, id, cell_index); |
7ae6478b SK |
1264 | if (IS_ERR(cell)) |
1265 | __nvmem_device_put(nvmem); | |
1266 | ||
69aba794 | 1267 | return cell; |
69aba794 SK |
1268 | } |
1269 | EXPORT_SYMBOL_GPL(of_nvmem_cell_get); | |
1270 | #endif | |
1271 | ||
1272 | /** | |
1273 | * nvmem_cell_get() - Get nvmem cell of device form a given cell name | |
1274 | * | |
29143268 | 1275 | * @dev: Device that requests the nvmem cell. |
165589f0 BG |
1276 | * @id: nvmem cell name to get (this corresponds with the name from the |
1277 | * nvmem-cell-names property for DT systems and with the con_id from | |
1278 | * the lookup entry for non-DT systems). | |
69aba794 SK |
1279 | * |
1280 | * Return: Will be an ERR_PTR() on error or a valid pointer | |
1281 | * to a struct nvmem_cell. The nvmem_cell will be freed by the | |
1282 | * nvmem_cell_put(). | |
1283 | */ | |
165589f0 | 1284 | struct nvmem_cell *nvmem_cell_get(struct device *dev, const char *id) |
69aba794 SK |
1285 | { |
1286 | struct nvmem_cell *cell; | |
1287 | ||
1288 | if (dev->of_node) { /* try dt first */ | |
165589f0 | 1289 | cell = of_nvmem_cell_get(dev->of_node, id); |
69aba794 SK |
1290 | if (!IS_ERR(cell) || PTR_ERR(cell) == -EPROBE_DEFER) |
1291 | return cell; | |
1292 | } | |
1293 | ||
165589f0 BG |
1294 | /* NULL cell id only allowed for device tree; invalid otherwise */ |
1295 | if (!id) | |
87ed1405 DA |
1296 | return ERR_PTR(-EINVAL); |
1297 | ||
165589f0 | 1298 | return nvmem_cell_get_from_lookup(dev, id); |
69aba794 SK |
1299 | } |
1300 | EXPORT_SYMBOL_GPL(nvmem_cell_get); | |
1301 | ||
1302 | static void devm_nvmem_cell_release(struct device *dev, void *res) | |
1303 | { | |
1304 | nvmem_cell_put(*(struct nvmem_cell **)res); | |
1305 | } | |
1306 | ||
1307 | /** | |
1308 | * devm_nvmem_cell_get() - Get nvmem cell of device form a given id | |
1309 | * | |
29143268 VG |
1310 | * @dev: Device that requests the nvmem cell. |
1311 | * @id: nvmem cell name id to get. | |
69aba794 SK |
1312 | * |
1313 | * Return: Will be an ERR_PTR() on error or a valid pointer | |
1314 | * to a struct nvmem_cell. The nvmem_cell will be freed by the | |
1315 | * automatically once the device is freed. | |
1316 | */ | |
1317 | struct nvmem_cell *devm_nvmem_cell_get(struct device *dev, const char *id) | |
1318 | { | |
1319 | struct nvmem_cell **ptr, *cell; | |
1320 | ||
1321 | ptr = devres_alloc(devm_nvmem_cell_release, sizeof(*ptr), GFP_KERNEL); | |
1322 | if (!ptr) | |
1323 | return ERR_PTR(-ENOMEM); | |
1324 | ||
1325 | cell = nvmem_cell_get(dev, id); | |
1326 | if (!IS_ERR(cell)) { | |
1327 | *ptr = cell; | |
1328 | devres_add(dev, ptr); | |
1329 | } else { | |
1330 | devres_free(ptr); | |
1331 | } | |
1332 | ||
1333 | return cell; | |
1334 | } | |
1335 | EXPORT_SYMBOL_GPL(devm_nvmem_cell_get); | |
1336 | ||
1337 | static int devm_nvmem_cell_match(struct device *dev, void *res, void *data) | |
1338 | { | |
1339 | struct nvmem_cell **c = res; | |
1340 | ||
1341 | if (WARN_ON(!c || !*c)) | |
1342 | return 0; | |
1343 | ||
1344 | return *c == data; | |
1345 | } | |
1346 | ||
1347 | /** | |
1348 | * devm_nvmem_cell_put() - Release previously allocated nvmem cell | |
1349 | * from devm_nvmem_cell_get. | |
1350 | * | |
29143268 VG |
1351 | * @dev: Device that requests the nvmem cell. |
1352 | * @cell: Previously allocated nvmem cell by devm_nvmem_cell_get(). | |
69aba794 SK |
1353 | */ |
1354 | void devm_nvmem_cell_put(struct device *dev, struct nvmem_cell *cell) | |
1355 | { | |
1356 | int ret; | |
1357 | ||
1358 | ret = devres_release(dev, devm_nvmem_cell_release, | |
1359 | devm_nvmem_cell_match, cell); | |
1360 | ||
1361 | WARN_ON(ret); | |
1362 | } | |
1363 | EXPORT_SYMBOL(devm_nvmem_cell_put); | |
1364 | ||
1365 | /** | |
1366 | * nvmem_cell_put() - Release previously allocated nvmem cell. | |
1367 | * | |
29143268 | 1368 | * @cell: Previously allocated nvmem cell by nvmem_cell_get(). |
69aba794 SK |
1369 | */ |
1370 | void nvmem_cell_put(struct nvmem_cell *cell) | |
1371 | { | |
7ae6478b SK |
1372 | struct nvmem_device *nvmem = cell->entry->nvmem; |
1373 | ||
1374 | if (cell->id) | |
1375 | kfree_const(cell->id); | |
69aba794 | 1376 | |
7ae6478b | 1377 | kfree(cell); |
69aba794 | 1378 | __nvmem_device_put(nvmem); |
69aba794 SK |
1379 | } |
1380 | EXPORT_SYMBOL_GPL(nvmem_cell_put); | |
1381 | ||
7ae6478b | 1382 | static void nvmem_shift_read_buffer_in_place(struct nvmem_cell_entry *cell, void *buf) |
69aba794 SK |
1383 | { |
1384 | u8 *p, *b; | |
2fe518fe | 1385 | int i, extra, bit_offset = cell->bit_offset; |
69aba794 SK |
1386 | |
1387 | p = b = buf; | |
1388 | if (bit_offset) { | |
1389 | /* First shift */ | |
1390 | *b++ >>= bit_offset; | |
1391 | ||
1392 | /* setup rest of the bytes if any */ | |
1393 | for (i = 1; i < cell->bytes; i++) { | |
1394 | /* Get bits from next byte and shift them towards msb */ | |
1395 | *p |= *b << (BITS_PER_BYTE - bit_offset); | |
1396 | ||
1397 | p = b; | |
1398 | *b++ >>= bit_offset; | |
1399 | } | |
2fe518fe JRO |
1400 | } else { |
1401 | /* point to the msb */ | |
1402 | p += cell->bytes - 1; | |
69aba794 | 1403 | } |
2fe518fe JRO |
1404 | |
1405 | /* result fits in less bytes */ | |
1406 | extra = cell->bytes - DIV_ROUND_UP(cell->nbits, BITS_PER_BYTE); | |
1407 | while (--extra >= 0) | |
1408 | *p-- = 0; | |
1409 | ||
69aba794 | 1410 | /* clear msb bits if any leftover in the last byte */ |
5d388fa0 SB |
1411 | if (cell->nbits % BITS_PER_BYTE) |
1412 | *p &= GENMASK((cell->nbits % BITS_PER_BYTE) - 1, 0); | |
69aba794 SK |
1413 | } |
1414 | ||
1415 | static int __nvmem_cell_read(struct nvmem_device *nvmem, | |
5d8e6e6c MW |
1416 | struct nvmem_cell_entry *cell, |
1417 | void *buf, size_t *len, const char *id, int index) | |
69aba794 SK |
1418 | { |
1419 | int rc; | |
1420 | ||
795ddd18 | 1421 | rc = nvmem_reg_read(nvmem, cell->offset, buf, cell->bytes); |
69aba794 | 1422 | |
287980e4 | 1423 | if (rc) |
69aba794 SK |
1424 | return rc; |
1425 | ||
1426 | /* shift bits in-place */ | |
cbf854ab | 1427 | if (cell->bit_offset || cell->nbits) |
69aba794 SK |
1428 | nvmem_shift_read_buffer_in_place(cell, buf); |
1429 | ||
5008062f | 1430 | if (nvmem->cell_post_process) { |
5d8e6e6c | 1431 | rc = nvmem->cell_post_process(nvmem->priv, id, index, |
5008062f SK |
1432 | cell->offset, buf, cell->bytes); |
1433 | if (rc) | |
1434 | return rc; | |
1435 | } | |
1436 | ||
3b4a6877 VG |
1437 | if (len) |
1438 | *len = cell->bytes; | |
69aba794 SK |
1439 | |
1440 | return 0; | |
1441 | } | |
1442 | ||
1443 | /** | |
1444 | * nvmem_cell_read() - Read a given nvmem cell | |
1445 | * | |
1446 | * @cell: nvmem cell to be read. | |
3b4a6877 VG |
1447 | * @len: pointer to length of cell which will be populated on successful read; |
1448 | * can be NULL. | |
69aba794 | 1449 | * |
b577fafc BN |
1450 | * Return: ERR_PTR() on error or a valid pointer to a buffer on success. The |
1451 | * buffer should be freed by the consumer with a kfree(). | |
69aba794 SK |
1452 | */ |
1453 | void *nvmem_cell_read(struct nvmem_cell *cell, size_t *len) | |
1454 | { | |
7ae6478b | 1455 | struct nvmem_device *nvmem = cell->entry->nvmem; |
69aba794 SK |
1456 | u8 *buf; |
1457 | int rc; | |
1458 | ||
795ddd18 | 1459 | if (!nvmem) |
69aba794 SK |
1460 | return ERR_PTR(-EINVAL); |
1461 | ||
7ae6478b | 1462 | buf = kzalloc(cell->entry->bytes, GFP_KERNEL); |
69aba794 SK |
1463 | if (!buf) |
1464 | return ERR_PTR(-ENOMEM); | |
1465 | ||
5d8e6e6c | 1466 | rc = __nvmem_cell_read(nvmem, cell->entry, buf, len, cell->id, cell->index); |
287980e4 | 1467 | if (rc) { |
69aba794 SK |
1468 | kfree(buf); |
1469 | return ERR_PTR(rc); | |
1470 | } | |
1471 | ||
1472 | return buf; | |
1473 | } | |
1474 | EXPORT_SYMBOL_GPL(nvmem_cell_read); | |
1475 | ||
7ae6478b | 1476 | static void *nvmem_cell_prepare_write_buffer(struct nvmem_cell_entry *cell, |
f7c04f16 | 1477 | u8 *_buf, int len) |
69aba794 SK |
1478 | { |
1479 | struct nvmem_device *nvmem = cell->nvmem; | |
1480 | int i, rc, nbits, bit_offset = cell->bit_offset; | |
1481 | u8 v, *p, *buf, *b, pbyte, pbits; | |
1482 | ||
1483 | nbits = cell->nbits; | |
1484 | buf = kzalloc(cell->bytes, GFP_KERNEL); | |
1485 | if (!buf) | |
1486 | return ERR_PTR(-ENOMEM); | |
1487 | ||
1488 | memcpy(buf, _buf, len); | |
1489 | p = b = buf; | |
1490 | ||
1491 | if (bit_offset) { | |
1492 | pbyte = *b; | |
1493 | *b <<= bit_offset; | |
1494 | ||
1495 | /* setup the first byte with lsb bits from nvmem */ | |
795ddd18 | 1496 | rc = nvmem_reg_read(nvmem, cell->offset, &v, 1); |
50808bfc MM |
1497 | if (rc) |
1498 | goto err; | |
69aba794 SK |
1499 | *b++ |= GENMASK(bit_offset - 1, 0) & v; |
1500 | ||
1501 | /* setup rest of the byte if any */ | |
1502 | for (i = 1; i < cell->bytes; i++) { | |
1503 | /* Get last byte bits and shift them towards lsb */ | |
1504 | pbits = pbyte >> (BITS_PER_BYTE - 1 - bit_offset); | |
1505 | pbyte = *b; | |
1506 | p = b; | |
1507 | *b <<= bit_offset; | |
1508 | *b++ |= pbits; | |
1509 | } | |
1510 | } | |
1511 | ||
1512 | /* if it's not end on byte boundary */ | |
1513 | if ((nbits + bit_offset) % BITS_PER_BYTE) { | |
1514 | /* setup the last byte with msb bits from nvmem */ | |
795ddd18 | 1515 | rc = nvmem_reg_read(nvmem, |
69aba794 | 1516 | cell->offset + cell->bytes - 1, &v, 1); |
50808bfc MM |
1517 | if (rc) |
1518 | goto err; | |
69aba794 SK |
1519 | *p |= GENMASK(7, (nbits + bit_offset) % BITS_PER_BYTE) & v; |
1520 | ||
1521 | } | |
1522 | ||
1523 | return buf; | |
50808bfc MM |
1524 | err: |
1525 | kfree(buf); | |
1526 | return ERR_PTR(rc); | |
69aba794 SK |
1527 | } |
1528 | ||
7ae6478b | 1529 | static int __nvmem_cell_entry_write(struct nvmem_cell_entry *cell, void *buf, size_t len) |
69aba794 SK |
1530 | { |
1531 | struct nvmem_device *nvmem = cell->nvmem; | |
1532 | int rc; | |
1533 | ||
795ddd18 | 1534 | if (!nvmem || nvmem->read_only || |
69aba794 SK |
1535 | (cell->bit_offset == 0 && len != cell->bytes)) |
1536 | return -EINVAL; | |
1537 | ||
1538 | if (cell->bit_offset || cell->nbits) { | |
1539 | buf = nvmem_cell_prepare_write_buffer(cell, buf, len); | |
1540 | if (IS_ERR(buf)) | |
1541 | return PTR_ERR(buf); | |
1542 | } | |
1543 | ||
795ddd18 | 1544 | rc = nvmem_reg_write(nvmem, cell->offset, buf, cell->bytes); |
69aba794 SK |
1545 | |
1546 | /* free the tmp buffer */ | |
ace22170 | 1547 | if (cell->bit_offset || cell->nbits) |
69aba794 SK |
1548 | kfree(buf); |
1549 | ||
287980e4 | 1550 | if (rc) |
69aba794 SK |
1551 | return rc; |
1552 | ||
1553 | return len; | |
1554 | } | |
7ae6478b SK |
1555 | |
1556 | /** | |
1557 | * nvmem_cell_write() - Write to a given nvmem cell | |
1558 | * | |
1559 | * @cell: nvmem cell to be written. | |
1560 | * @buf: Buffer to be written. | |
1561 | * @len: length of buffer to be written to nvmem cell. | |
1562 | * | |
1563 | * Return: length of bytes written or negative on failure. | |
1564 | */ | |
1565 | int nvmem_cell_write(struct nvmem_cell *cell, void *buf, size_t len) | |
1566 | { | |
1567 | return __nvmem_cell_entry_write(cell->entry, buf, len); | |
1568 | } | |
1569 | ||
69aba794 SK |
1570 | EXPORT_SYMBOL_GPL(nvmem_cell_write); |
1571 | ||
6bb317ce YL |
1572 | static int nvmem_cell_read_common(struct device *dev, const char *cell_id, |
1573 | void *val, size_t count) | |
0a9b2d1c FG |
1574 | { |
1575 | struct nvmem_cell *cell; | |
1576 | void *buf; | |
1577 | size_t len; | |
1578 | ||
1579 | cell = nvmem_cell_get(dev, cell_id); | |
1580 | if (IS_ERR(cell)) | |
1581 | return PTR_ERR(cell); | |
1582 | ||
1583 | buf = nvmem_cell_read(cell, &len); | |
1584 | if (IS_ERR(buf)) { | |
1585 | nvmem_cell_put(cell); | |
1586 | return PTR_ERR(buf); | |
1587 | } | |
6bb317ce | 1588 | if (len != count) { |
0a9b2d1c FG |
1589 | kfree(buf); |
1590 | nvmem_cell_put(cell); | |
1591 | return -EINVAL; | |
1592 | } | |
6bb317ce | 1593 | memcpy(val, buf, count); |
0a9b2d1c FG |
1594 | kfree(buf); |
1595 | nvmem_cell_put(cell); | |
1596 | ||
1597 | return 0; | |
1598 | } | |
6bb317ce | 1599 | |
5037d368 AF |
1600 | /** |
1601 | * nvmem_cell_read_u8() - Read a cell value as a u8 | |
1602 | * | |
1603 | * @dev: Device that requests the nvmem cell. | |
1604 | * @cell_id: Name of nvmem cell to read. | |
1605 | * @val: pointer to output value. | |
1606 | * | |
1607 | * Return: 0 on success or negative errno. | |
1608 | */ | |
1609 | int nvmem_cell_read_u8(struct device *dev, const char *cell_id, u8 *val) | |
1610 | { | |
1611 | return nvmem_cell_read_common(dev, cell_id, val, sizeof(*val)); | |
1612 | } | |
1613 | EXPORT_SYMBOL_GPL(nvmem_cell_read_u8); | |
1614 | ||
6bb317ce | 1615 | /** |
3a758071 | 1616 | * nvmem_cell_read_u16() - Read a cell value as a u16 |
6bb317ce YL |
1617 | * |
1618 | * @dev: Device that requests the nvmem cell. | |
1619 | * @cell_id: Name of nvmem cell to read. | |
1620 | * @val: pointer to output value. | |
1621 | * | |
1622 | * Return: 0 on success or negative errno. | |
1623 | */ | |
1624 | int nvmem_cell_read_u16(struct device *dev, const char *cell_id, u16 *val) | |
1625 | { | |
1626 | return nvmem_cell_read_common(dev, cell_id, val, sizeof(*val)); | |
1627 | } | |
0a9b2d1c FG |
1628 | EXPORT_SYMBOL_GPL(nvmem_cell_read_u16); |
1629 | ||
d026d70a | 1630 | /** |
3a758071 | 1631 | * nvmem_cell_read_u32() - Read a cell value as a u32 |
d026d70a LC |
1632 | * |
1633 | * @dev: Device that requests the nvmem cell. | |
1634 | * @cell_id: Name of nvmem cell to read. | |
1635 | * @val: pointer to output value. | |
1636 | * | |
1637 | * Return: 0 on success or negative errno. | |
1638 | */ | |
1639 | int nvmem_cell_read_u32(struct device *dev, const char *cell_id, u32 *val) | |
1640 | { | |
6bb317ce | 1641 | return nvmem_cell_read_common(dev, cell_id, val, sizeof(*val)); |
d026d70a LC |
1642 | } |
1643 | EXPORT_SYMBOL_GPL(nvmem_cell_read_u32); | |
1644 | ||
8b977c54 | 1645 | /** |
3a758071 | 1646 | * nvmem_cell_read_u64() - Read a cell value as a u64 |
8b977c54 YL |
1647 | * |
1648 | * @dev: Device that requests the nvmem cell. | |
1649 | * @cell_id: Name of nvmem cell to read. | |
1650 | * @val: pointer to output value. | |
1651 | * | |
1652 | * Return: 0 on success or negative errno. | |
1653 | */ | |
1654 | int nvmem_cell_read_u64(struct device *dev, const char *cell_id, u64 *val) | |
1655 | { | |
1656 | return nvmem_cell_read_common(dev, cell_id, val, sizeof(*val)); | |
1657 | } | |
1658 | EXPORT_SYMBOL_GPL(nvmem_cell_read_u64); | |
1659 | ||
1f7b4d87 DA |
1660 | static const void *nvmem_cell_read_variable_common(struct device *dev, |
1661 | const char *cell_id, | |
1662 | size_t max_len, size_t *len) | |
a28e824f DA |
1663 | { |
1664 | struct nvmem_cell *cell; | |
1665 | int nbits; | |
1666 | void *buf; | |
1667 | ||
1668 | cell = nvmem_cell_get(dev, cell_id); | |
1669 | if (IS_ERR(cell)) | |
1670 | return cell; | |
1671 | ||
7ae6478b | 1672 | nbits = cell->entry->nbits; |
a28e824f DA |
1673 | buf = nvmem_cell_read(cell, len); |
1674 | nvmem_cell_put(cell); | |
1675 | if (IS_ERR(buf)) | |
1676 | return buf; | |
1677 | ||
1678 | /* | |
1679 | * If nbits is set then nvmem_cell_read() can significantly exaggerate | |
1680 | * the length of the real data. Throw away the extra junk. | |
1681 | */ | |
1682 | if (nbits) | |
1683 | *len = DIV_ROUND_UP(nbits, 8); | |
1684 | ||
1685 | if (*len > max_len) { | |
1686 | kfree(buf); | |
1687 | return ERR_PTR(-ERANGE); | |
1688 | } | |
1689 | ||
1690 | return buf; | |
1691 | } | |
1692 | ||
1693 | /** | |
1694 | * nvmem_cell_read_variable_le_u32() - Read up to 32-bits of data as a little endian number. | |
1695 | * | |
1696 | * @dev: Device that requests the nvmem cell. | |
1697 | * @cell_id: Name of nvmem cell to read. | |
1698 | * @val: pointer to output value. | |
1699 | * | |
1700 | * Return: 0 on success or negative errno. | |
1701 | */ | |
1702 | int nvmem_cell_read_variable_le_u32(struct device *dev, const char *cell_id, | |
1703 | u32 *val) | |
1704 | { | |
1705 | size_t len; | |
1f7b4d87 | 1706 | const u8 *buf; |
a28e824f DA |
1707 | int i; |
1708 | ||
1709 | buf = nvmem_cell_read_variable_common(dev, cell_id, sizeof(*val), &len); | |
1710 | if (IS_ERR(buf)) | |
1711 | return PTR_ERR(buf); | |
1712 | ||
1713 | /* Copy w/ implicit endian conversion */ | |
1714 | *val = 0; | |
1715 | for (i = 0; i < len; i++) | |
1716 | *val |= buf[i] << (8 * i); | |
1717 | ||
1718 | kfree(buf); | |
1719 | ||
1720 | return 0; | |
1721 | } | |
1722 | EXPORT_SYMBOL_GPL(nvmem_cell_read_variable_le_u32); | |
1723 | ||
1724 | /** | |
1725 | * nvmem_cell_read_variable_le_u64() - Read up to 64-bits of data as a little endian number. | |
1726 | * | |
1727 | * @dev: Device that requests the nvmem cell. | |
1728 | * @cell_id: Name of nvmem cell to read. | |
1729 | * @val: pointer to output value. | |
1730 | * | |
1731 | * Return: 0 on success or negative errno. | |
1732 | */ | |
1733 | int nvmem_cell_read_variable_le_u64(struct device *dev, const char *cell_id, | |
1734 | u64 *val) | |
1735 | { | |
1736 | size_t len; | |
1f7b4d87 | 1737 | const u8 *buf; |
a28e824f DA |
1738 | int i; |
1739 | ||
1740 | buf = nvmem_cell_read_variable_common(dev, cell_id, sizeof(*val), &len); | |
1741 | if (IS_ERR(buf)) | |
1742 | return PTR_ERR(buf); | |
1743 | ||
1744 | /* Copy w/ implicit endian conversion */ | |
1745 | *val = 0; | |
1746 | for (i = 0; i < len; i++) | |
55022fde | 1747 | *val |= (uint64_t)buf[i] << (8 * i); |
a28e824f DA |
1748 | |
1749 | kfree(buf); | |
1750 | ||
1751 | return 0; | |
1752 | } | |
1753 | EXPORT_SYMBOL_GPL(nvmem_cell_read_variable_le_u64); | |
1754 | ||
e2a5402e SK |
1755 | /** |
1756 | * nvmem_device_cell_read() - Read a given nvmem device and cell | |
1757 | * | |
1758 | * @nvmem: nvmem device to read from. | |
1759 | * @info: nvmem cell info to be read. | |
1760 | * @buf: buffer pointer which will be populated on successful read. | |
1761 | * | |
1762 | * Return: length of successful bytes read on success and negative | |
1763 | * error code on error. | |
1764 | */ | |
1765 | ssize_t nvmem_device_cell_read(struct nvmem_device *nvmem, | |
1766 | struct nvmem_cell_info *info, void *buf) | |
1767 | { | |
7ae6478b | 1768 | struct nvmem_cell_entry cell; |
e2a5402e SK |
1769 | int rc; |
1770 | ssize_t len; | |
1771 | ||
795ddd18 | 1772 | if (!nvmem) |
e2a5402e SK |
1773 | return -EINVAL; |
1774 | ||
7ae6478b | 1775 | rc = nvmem_cell_info_to_nvmem_cell_entry_nodup(nvmem, info, &cell); |
287980e4 | 1776 | if (rc) |
e2a5402e SK |
1777 | return rc; |
1778 | ||
5d8e6e6c | 1779 | rc = __nvmem_cell_read(nvmem, &cell, buf, &len, NULL, 0); |
287980e4 | 1780 | if (rc) |
e2a5402e SK |
1781 | return rc; |
1782 | ||
1783 | return len; | |
1784 | } | |
1785 | EXPORT_SYMBOL_GPL(nvmem_device_cell_read); | |
1786 | ||
1787 | /** | |
1788 | * nvmem_device_cell_write() - Write cell to a given nvmem device | |
1789 | * | |
1790 | * @nvmem: nvmem device to be written to. | |
29143268 | 1791 | * @info: nvmem cell info to be written. |
e2a5402e SK |
1792 | * @buf: buffer to be written to cell. |
1793 | * | |
1794 | * Return: length of bytes written or negative error code on failure. | |
48f63a2c | 1795 | */ |
e2a5402e SK |
1796 | int nvmem_device_cell_write(struct nvmem_device *nvmem, |
1797 | struct nvmem_cell_info *info, void *buf) | |
1798 | { | |
7ae6478b | 1799 | struct nvmem_cell_entry cell; |
e2a5402e SK |
1800 | int rc; |
1801 | ||
795ddd18 | 1802 | if (!nvmem) |
e2a5402e SK |
1803 | return -EINVAL; |
1804 | ||
7ae6478b | 1805 | rc = nvmem_cell_info_to_nvmem_cell_entry_nodup(nvmem, info, &cell); |
287980e4 | 1806 | if (rc) |
e2a5402e SK |
1807 | return rc; |
1808 | ||
7ae6478b | 1809 | return __nvmem_cell_entry_write(&cell, buf, cell.bytes); |
e2a5402e SK |
1810 | } |
1811 | EXPORT_SYMBOL_GPL(nvmem_device_cell_write); | |
1812 | ||
1813 | /** | |
1814 | * nvmem_device_read() - Read from a given nvmem device | |
1815 | * | |
1816 | * @nvmem: nvmem device to read from. | |
1817 | * @offset: offset in nvmem device. | |
1818 | * @bytes: number of bytes to read. | |
1819 | * @buf: buffer pointer which will be populated on successful read. | |
1820 | * | |
1821 | * Return: length of successful bytes read on success and negative | |
1822 | * error code on error. | |
1823 | */ | |
1824 | int nvmem_device_read(struct nvmem_device *nvmem, | |
1825 | unsigned int offset, | |
1826 | size_t bytes, void *buf) | |
1827 | { | |
1828 | int rc; | |
1829 | ||
795ddd18 | 1830 | if (!nvmem) |
e2a5402e SK |
1831 | return -EINVAL; |
1832 | ||
795ddd18 | 1833 | rc = nvmem_reg_read(nvmem, offset, buf, bytes); |
e2a5402e | 1834 | |
287980e4 | 1835 | if (rc) |
e2a5402e SK |
1836 | return rc; |
1837 | ||
1838 | return bytes; | |
1839 | } | |
1840 | EXPORT_SYMBOL_GPL(nvmem_device_read); | |
1841 | ||
1842 | /** | |
1843 | * nvmem_device_write() - Write cell to a given nvmem device | |
1844 | * | |
1845 | * @nvmem: nvmem device to be written to. | |
1846 | * @offset: offset in nvmem device. | |
1847 | * @bytes: number of bytes to write. | |
1848 | * @buf: buffer to be written. | |
1849 | * | |
1850 | * Return: length of bytes written or negative error code on failure. | |
48f63a2c | 1851 | */ |
e2a5402e SK |
1852 | int nvmem_device_write(struct nvmem_device *nvmem, |
1853 | unsigned int offset, | |
1854 | size_t bytes, void *buf) | |
1855 | { | |
1856 | int rc; | |
1857 | ||
795ddd18 | 1858 | if (!nvmem) |
e2a5402e SK |
1859 | return -EINVAL; |
1860 | ||
795ddd18 | 1861 | rc = nvmem_reg_write(nvmem, offset, buf, bytes); |
e2a5402e | 1862 | |
287980e4 | 1863 | if (rc) |
e2a5402e SK |
1864 | return rc; |
1865 | ||
1866 | ||
1867 | return bytes; | |
1868 | } | |
1869 | EXPORT_SYMBOL_GPL(nvmem_device_write); | |
1870 | ||
b985f4cb BG |
1871 | /** |
1872 | * nvmem_add_cell_table() - register a table of cell info entries | |
1873 | * | |
1874 | * @table: table of cell info entries | |
1875 | */ | |
1876 | void nvmem_add_cell_table(struct nvmem_cell_table *table) | |
1877 | { | |
1878 | mutex_lock(&nvmem_cell_mutex); | |
1879 | list_add_tail(&table->node, &nvmem_cell_tables); | |
1880 | mutex_unlock(&nvmem_cell_mutex); | |
1881 | } | |
1882 | EXPORT_SYMBOL_GPL(nvmem_add_cell_table); | |
1883 | ||
1884 | /** | |
1885 | * nvmem_del_cell_table() - remove a previously registered cell info table | |
1886 | * | |
1887 | * @table: table of cell info entries | |
1888 | */ | |
1889 | void nvmem_del_cell_table(struct nvmem_cell_table *table) | |
1890 | { | |
1891 | mutex_lock(&nvmem_cell_mutex); | |
1892 | list_del(&table->node); | |
1893 | mutex_unlock(&nvmem_cell_mutex); | |
1894 | } | |
1895 | EXPORT_SYMBOL_GPL(nvmem_del_cell_table); | |
1896 | ||
506157be BG |
1897 | /** |
1898 | * nvmem_add_cell_lookups() - register a list of cell lookup entries | |
1899 | * | |
1900 | * @entries: array of cell lookup entries | |
1901 | * @nentries: number of cell lookup entries in the array | |
1902 | */ | |
1903 | void nvmem_add_cell_lookups(struct nvmem_cell_lookup *entries, size_t nentries) | |
1904 | { | |
1905 | int i; | |
1906 | ||
1907 | mutex_lock(&nvmem_lookup_mutex); | |
1908 | for (i = 0; i < nentries; i++) | |
1909 | list_add_tail(&entries[i].node, &nvmem_lookup_list); | |
1910 | mutex_unlock(&nvmem_lookup_mutex); | |
1911 | } | |
1912 | EXPORT_SYMBOL_GPL(nvmem_add_cell_lookups); | |
1913 | ||
1914 | /** | |
1915 | * nvmem_del_cell_lookups() - remove a list of previously added cell lookup | |
1916 | * entries | |
1917 | * | |
1918 | * @entries: array of cell lookup entries | |
1919 | * @nentries: number of cell lookup entries in the array | |
1920 | */ | |
1921 | void nvmem_del_cell_lookups(struct nvmem_cell_lookup *entries, size_t nentries) | |
1922 | { | |
1923 | int i; | |
1924 | ||
1925 | mutex_lock(&nvmem_lookup_mutex); | |
1926 | for (i = 0; i < nentries; i++) | |
1927 | list_del(&entries[i].node); | |
1928 | mutex_unlock(&nvmem_lookup_mutex); | |
1929 | } | |
1930 | EXPORT_SYMBOL_GPL(nvmem_del_cell_lookups); | |
1931 | ||
d7b9fd16 BG |
1932 | /** |
1933 | * nvmem_dev_name() - Get the name of a given nvmem device. | |
1934 | * | |
1935 | * @nvmem: nvmem device. | |
1936 | * | |
1937 | * Return: name of the nvmem device. | |
1938 | */ | |
1939 | const char *nvmem_dev_name(struct nvmem_device *nvmem) | |
1940 | { | |
1941 | return dev_name(&nvmem->dev); | |
1942 | } | |
1943 | EXPORT_SYMBOL_GPL(nvmem_dev_name); | |
1944 | ||
eace75cf SK |
1945 | static int __init nvmem_init(void) |
1946 | { | |
1947 | return bus_register(&nvmem_bus_type); | |
1948 | } | |
1949 | ||
1950 | static void __exit nvmem_exit(void) | |
1951 | { | |
1952 | bus_unregister(&nvmem_bus_type); | |
1953 | } | |
1954 | ||
1955 | subsys_initcall(nvmem_init); | |
1956 | module_exit(nvmem_exit); | |
1957 | ||
1958 | MODULE_AUTHOR("Srinivas Kandagatla <srinivas.kandagatla@linaro.org"); | |
1959 | MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com"); | |
1960 | MODULE_DESCRIPTION("nvmem Driver Core"); | |
1961 | MODULE_LICENSE("GPL v2"); |