Commit | Line | Data |
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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 | 19 | #include <linux/slab.h> |
ae0c2d72 | 20 | #include "nvmem.h" |
b6c217ab | 21 | |
eace75cf SK |
22 | struct nvmem_cell { |
23 | const char *name; | |
24 | int offset; | |
25 | int bytes; | |
26 | int bit_offset; | |
27 | int nbits; | |
0749aa25 | 28 | struct device_node *np; |
eace75cf SK |
29 | struct nvmem_device *nvmem; |
30 | struct list_head node; | |
31 | }; | |
32 | ||
33 | static DEFINE_MUTEX(nvmem_mutex); | |
34 | static DEFINE_IDA(nvmem_ida); | |
35 | ||
b985f4cb BG |
36 | static DEFINE_MUTEX(nvmem_cell_mutex); |
37 | static LIST_HEAD(nvmem_cell_tables); | |
38 | ||
506157be BG |
39 | static DEFINE_MUTEX(nvmem_lookup_mutex); |
40 | static LIST_HEAD(nvmem_lookup_list); | |
41 | ||
bee1138b BG |
42 | static BLOCKING_NOTIFIER_HEAD(nvmem_notifier); |
43 | ||
b6c217ab | 44 | |
795ddd18 SK |
45 | static int nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset, |
46 | void *val, size_t bytes) | |
47 | { | |
48 | if (nvmem->reg_read) | |
49 | return nvmem->reg_read(nvmem->priv, offset, val, bytes); | |
50 | ||
51 | return -EINVAL; | |
52 | } | |
53 | ||
54 | static int nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset, | |
55 | void *val, size_t bytes) | |
56 | { | |
57 | if (nvmem->reg_write) | |
58 | return nvmem->reg_write(nvmem->priv, offset, val, bytes); | |
59 | ||
60 | return -EINVAL; | |
61 | } | |
eace75cf | 62 | |
eace75cf SK |
63 | static void nvmem_release(struct device *dev) |
64 | { | |
65 | struct nvmem_device *nvmem = to_nvmem_device(dev); | |
66 | ||
67 | ida_simple_remove(&nvmem_ida, nvmem->id); | |
68 | kfree(nvmem); | |
69 | } | |
70 | ||
71 | static const struct device_type nvmem_provider_type = { | |
72 | .release = nvmem_release, | |
73 | }; | |
74 | ||
75 | static struct bus_type nvmem_bus_type = { | |
76 | .name = "nvmem", | |
77 | }; | |
78 | ||
eace75cf SK |
79 | static void nvmem_cell_drop(struct nvmem_cell *cell) |
80 | { | |
bee1138b | 81 | blocking_notifier_call_chain(&nvmem_notifier, NVMEM_CELL_REMOVE, cell); |
c7235ee3 | 82 | mutex_lock(&nvmem_mutex); |
eace75cf | 83 | list_del(&cell->node); |
c7235ee3 | 84 | mutex_unlock(&nvmem_mutex); |
0749aa25 | 85 | of_node_put(cell->np); |
badcdff1 | 86 | kfree(cell->name); |
eace75cf SK |
87 | kfree(cell); |
88 | } | |
89 | ||
90 | static void nvmem_device_remove_all_cells(const struct nvmem_device *nvmem) | |
91 | { | |
1852183e | 92 | struct nvmem_cell *cell, *p; |
eace75cf | 93 | |
c7235ee3 BG |
94 | list_for_each_entry_safe(cell, p, &nvmem->cells, node) |
95 | nvmem_cell_drop(cell); | |
eace75cf SK |
96 | } |
97 | ||
98 | static void nvmem_cell_add(struct nvmem_cell *cell) | |
99 | { | |
c7235ee3 BG |
100 | mutex_lock(&nvmem_mutex); |
101 | list_add_tail(&cell->node, &cell->nvmem->cells); | |
102 | mutex_unlock(&nvmem_mutex); | |
bee1138b | 103 | blocking_notifier_call_chain(&nvmem_notifier, NVMEM_CELL_ADD, cell); |
eace75cf SK |
104 | } |
105 | ||
106 | static int nvmem_cell_info_to_nvmem_cell(struct nvmem_device *nvmem, | |
107 | const struct nvmem_cell_info *info, | |
108 | struct nvmem_cell *cell) | |
109 | { | |
110 | cell->nvmem = nvmem; | |
111 | cell->offset = info->offset; | |
112 | cell->bytes = info->bytes; | |
113 | cell->name = info->name; | |
114 | ||
115 | cell->bit_offset = info->bit_offset; | |
116 | cell->nbits = info->nbits; | |
117 | ||
118 | if (cell->nbits) | |
119 | cell->bytes = DIV_ROUND_UP(cell->nbits + cell->bit_offset, | |
120 | BITS_PER_BYTE); | |
121 | ||
122 | if (!IS_ALIGNED(cell->offset, nvmem->stride)) { | |
123 | dev_err(&nvmem->dev, | |
124 | "cell %s unaligned to nvmem stride %d\n", | |
125 | cell->name, nvmem->stride); | |
126 | return -EINVAL; | |
127 | } | |
128 | ||
129 | return 0; | |
130 | } | |
131 | ||
b3db17e4 AL |
132 | /** |
133 | * nvmem_add_cells() - Add cell information to an nvmem device | |
134 | * | |
135 | * @nvmem: nvmem device to add cells to. | |
136 | * @info: nvmem cell info to add to the device | |
137 | * @ncells: number of cells in info | |
138 | * | |
139 | * Return: 0 or negative error code on failure. | |
140 | */ | |
ef92ab30 | 141 | static int nvmem_add_cells(struct nvmem_device *nvmem, |
b3db17e4 AL |
142 | const struct nvmem_cell_info *info, |
143 | int ncells) | |
eace75cf SK |
144 | { |
145 | struct nvmem_cell **cells; | |
eace75cf SK |
146 | int i, rval; |
147 | ||
b3db17e4 | 148 | cells = kcalloc(ncells, sizeof(*cells), GFP_KERNEL); |
eace75cf SK |
149 | if (!cells) |
150 | return -ENOMEM; | |
151 | ||
b3db17e4 | 152 | for (i = 0; i < ncells; i++) { |
eace75cf SK |
153 | cells[i] = kzalloc(sizeof(**cells), GFP_KERNEL); |
154 | if (!cells[i]) { | |
155 | rval = -ENOMEM; | |
156 | goto err; | |
157 | } | |
158 | ||
159 | rval = nvmem_cell_info_to_nvmem_cell(nvmem, &info[i], cells[i]); | |
287980e4 | 160 | if (rval) { |
eace75cf SK |
161 | kfree(cells[i]); |
162 | goto err; | |
163 | } | |
164 | ||
165 | nvmem_cell_add(cells[i]); | |
166 | } | |
167 | ||
eace75cf SK |
168 | /* remove tmp array */ |
169 | kfree(cells); | |
170 | ||
171 | return 0; | |
172 | err: | |
dfdf1414 | 173 | while (i--) |
eace75cf SK |
174 | nvmem_cell_drop(cells[i]); |
175 | ||
dfdf1414 RV |
176 | kfree(cells); |
177 | ||
eace75cf SK |
178 | return rval; |
179 | } | |
180 | ||
bee1138b BG |
181 | /** |
182 | * nvmem_register_notifier() - Register a notifier block for nvmem events. | |
183 | * | |
184 | * @nb: notifier block to be called on nvmem events. | |
185 | * | |
186 | * Return: 0 on success, negative error number on failure. | |
187 | */ | |
188 | int nvmem_register_notifier(struct notifier_block *nb) | |
189 | { | |
190 | return blocking_notifier_chain_register(&nvmem_notifier, nb); | |
191 | } | |
192 | EXPORT_SYMBOL_GPL(nvmem_register_notifier); | |
193 | ||
194 | /** | |
195 | * nvmem_unregister_notifier() - Unregister a notifier block for nvmem events. | |
196 | * | |
197 | * @nb: notifier block to be unregistered. | |
198 | * | |
199 | * Return: 0 on success, negative error number on failure. | |
200 | */ | |
201 | int nvmem_unregister_notifier(struct notifier_block *nb) | |
202 | { | |
203 | return blocking_notifier_chain_unregister(&nvmem_notifier, nb); | |
204 | } | |
205 | EXPORT_SYMBOL_GPL(nvmem_unregister_notifier); | |
206 | ||
b985f4cb BG |
207 | static int nvmem_add_cells_from_table(struct nvmem_device *nvmem) |
208 | { | |
209 | const struct nvmem_cell_info *info; | |
210 | struct nvmem_cell_table *table; | |
211 | struct nvmem_cell *cell; | |
212 | int rval = 0, i; | |
213 | ||
214 | mutex_lock(&nvmem_cell_mutex); | |
215 | list_for_each_entry(table, &nvmem_cell_tables, node) { | |
216 | if (strcmp(nvmem_dev_name(nvmem), table->nvmem_name) == 0) { | |
217 | for (i = 0; i < table->ncells; i++) { | |
218 | info = &table->cells[i]; | |
219 | ||
220 | cell = kzalloc(sizeof(*cell), GFP_KERNEL); | |
221 | if (!cell) { | |
222 | rval = -ENOMEM; | |
223 | goto out; | |
224 | } | |
225 | ||
226 | rval = nvmem_cell_info_to_nvmem_cell(nvmem, | |
227 | info, | |
228 | cell); | |
229 | if (rval) { | |
230 | kfree(cell); | |
231 | goto out; | |
232 | } | |
233 | ||
234 | nvmem_cell_add(cell); | |
235 | } | |
236 | } | |
237 | } | |
238 | ||
239 | out: | |
240 | mutex_unlock(&nvmem_cell_mutex); | |
241 | return rval; | |
242 | } | |
243 | ||
506157be BG |
244 | static struct nvmem_cell * |
245 | nvmem_find_cell_by_name(struct nvmem_device *nvmem, const char *cell_id) | |
246 | { | |
1c832674 | 247 | struct nvmem_cell *iter, *cell = NULL; |
506157be BG |
248 | |
249 | mutex_lock(&nvmem_mutex); | |
1c832674 AB |
250 | list_for_each_entry(iter, &nvmem->cells, node) { |
251 | if (strcmp(cell_id, iter->name) == 0) { | |
252 | cell = iter; | |
506157be | 253 | break; |
1c832674 | 254 | } |
506157be BG |
255 | } |
256 | mutex_unlock(&nvmem_mutex); | |
257 | ||
258 | return cell; | |
259 | } | |
260 | ||
e888d445 BG |
261 | static int nvmem_add_cells_from_of(struct nvmem_device *nvmem) |
262 | { | |
263 | struct device_node *parent, *child; | |
264 | struct device *dev = &nvmem->dev; | |
265 | struct nvmem_cell *cell; | |
266 | const __be32 *addr; | |
267 | int len; | |
268 | ||
269 | parent = dev->of_node; | |
270 | ||
271 | for_each_child_of_node(parent, child) { | |
272 | addr = of_get_property(child, "reg", &len); | |
273 | if (!addr || (len < 2 * sizeof(u32))) { | |
274 | dev_err(dev, "nvmem: invalid reg on %pOF\n", child); | |
275 | return -EINVAL; | |
276 | } | |
277 | ||
278 | cell = kzalloc(sizeof(*cell), GFP_KERNEL); | |
279 | if (!cell) | |
280 | return -ENOMEM; | |
281 | ||
282 | cell->nvmem = nvmem; | |
0749aa25 | 283 | cell->np = of_node_get(child); |
e888d445 BG |
284 | cell->offset = be32_to_cpup(addr++); |
285 | cell->bytes = be32_to_cpup(addr); | |
badcdff1 | 286 | cell->name = kasprintf(GFP_KERNEL, "%pOFn", child); |
e888d445 BG |
287 | |
288 | addr = of_get_property(child, "bits", &len); | |
289 | if (addr && len == (2 * sizeof(u32))) { | |
290 | cell->bit_offset = be32_to_cpup(addr++); | |
291 | cell->nbits = be32_to_cpup(addr); | |
292 | } | |
293 | ||
294 | if (cell->nbits) | |
295 | cell->bytes = DIV_ROUND_UP( | |
296 | cell->nbits + cell->bit_offset, | |
297 | BITS_PER_BYTE); | |
298 | ||
299 | if (!IS_ALIGNED(cell->offset, nvmem->stride)) { | |
300 | dev_err(dev, "cell %s unaligned to nvmem stride %d\n", | |
301 | cell->name, nvmem->stride); | |
302 | /* Cells already added will be freed later. */ | |
badcdff1 | 303 | kfree(cell->name); |
e888d445 BG |
304 | kfree(cell); |
305 | return -EINVAL; | |
306 | } | |
307 | ||
308 | nvmem_cell_add(cell); | |
309 | } | |
310 | ||
311 | return 0; | |
312 | } | |
313 | ||
eace75cf SK |
314 | /** |
315 | * nvmem_register() - Register a nvmem device for given nvmem_config. | |
316 | * Also creates an binary entry in /sys/bus/nvmem/devices/dev-name/nvmem | |
317 | * | |
318 | * @config: nvmem device configuration with which nvmem device is created. | |
319 | * | |
320 | * Return: Will be an ERR_PTR() on error or a valid pointer to nvmem_device | |
321 | * on success. | |
322 | */ | |
323 | ||
324 | struct nvmem_device *nvmem_register(const struct nvmem_config *config) | |
325 | { | |
326 | struct nvmem_device *nvmem; | |
eace75cf SK |
327 | int rval; |
328 | ||
329 | if (!config->dev) | |
330 | return ERR_PTR(-EINVAL); | |
331 | ||
eace75cf SK |
332 | nvmem = kzalloc(sizeof(*nvmem), GFP_KERNEL); |
333 | if (!nvmem) | |
334 | return ERR_PTR(-ENOMEM); | |
335 | ||
336 | rval = ida_simple_get(&nvmem_ida, 0, 0, GFP_KERNEL); | |
337 | if (rval < 0) { | |
338 | kfree(nvmem); | |
339 | return ERR_PTR(rval); | |
340 | } | |
341 | ||
c1de7f43 | 342 | kref_init(&nvmem->refcnt); |
c7235ee3 | 343 | INIT_LIST_HEAD(&nvmem->cells); |
c1de7f43 | 344 | |
eace75cf | 345 | nvmem->id = rval; |
eace75cf | 346 | nvmem->owner = config->owner; |
17eb18d6 MY |
347 | if (!nvmem->owner && config->dev->driver) |
348 | nvmem->owner = config->dev->driver->owner; | |
99897efd HK |
349 | nvmem->stride = config->stride ?: 1; |
350 | nvmem->word_size = config->word_size ?: 1; | |
795ddd18 | 351 | nvmem->size = config->size; |
eace75cf SK |
352 | nvmem->dev.type = &nvmem_provider_type; |
353 | nvmem->dev.bus = &nvmem_bus_type; | |
354 | nvmem->dev.parent = config->dev; | |
795ddd18 | 355 | nvmem->priv = config->priv; |
16688453 | 356 | nvmem->type = config->type; |
795ddd18 SK |
357 | nvmem->reg_read = config->reg_read; |
358 | nvmem->reg_write = config->reg_write; | |
517f14d9 BG |
359 | if (!config->no_of_node) |
360 | nvmem->dev.of_node = config->dev->of_node; | |
fd0f4906 AS |
361 | |
362 | if (config->id == -1 && config->name) { | |
363 | dev_set_name(&nvmem->dev, "%s", config->name); | |
364 | } else { | |
365 | dev_set_name(&nvmem->dev, "%s%d", | |
366 | config->name ? : "nvmem", | |
367 | config->name ? config->id : nvmem->id); | |
368 | } | |
eace75cf | 369 | |
1716cfe8 AB |
370 | nvmem->read_only = device_property_present(config->dev, "read-only") || |
371 | config->read_only || !nvmem->reg_write; | |
eace75cf | 372 | |
ae0c2d72 | 373 | nvmem->dev.groups = nvmem_sysfs_get_groups(nvmem, config); |
eace75cf SK |
374 | |
375 | device_initialize(&nvmem->dev); | |
376 | ||
377 | dev_dbg(&nvmem->dev, "Registering nvmem device %s\n", config->name); | |
378 | ||
379 | rval = device_add(&nvmem->dev); | |
b6c217ab | 380 | if (rval) |
3360acdf | 381 | goto err_put_device; |
b6c217ab AL |
382 | |
383 | if (config->compat) { | |
ae0c2d72 | 384 | rval = nvmem_sysfs_setup_compat(nvmem, config); |
b6c217ab | 385 | if (rval) |
3360acdf | 386 | goto err_device_del; |
eace75cf SK |
387 | } |
388 | ||
fa72d847 BG |
389 | if (config->cells) { |
390 | rval = nvmem_add_cells(nvmem, config->cells, config->ncells); | |
391 | if (rval) | |
392 | goto err_teardown_compat; | |
393 | } | |
eace75cf | 394 | |
b985f4cb BG |
395 | rval = nvmem_add_cells_from_table(nvmem); |
396 | if (rval) | |
397 | goto err_remove_cells; | |
398 | ||
e888d445 BG |
399 | rval = nvmem_add_cells_from_of(nvmem); |
400 | if (rval) | |
401 | goto err_remove_cells; | |
402 | ||
f4853e1c | 403 | blocking_notifier_call_chain(&nvmem_notifier, NVMEM_ADD, nvmem); |
bee1138b | 404 | |
eace75cf | 405 | return nvmem; |
3360acdf | 406 | |
b985f4cb BG |
407 | err_remove_cells: |
408 | nvmem_device_remove_all_cells(nvmem); | |
fa72d847 BG |
409 | err_teardown_compat: |
410 | if (config->compat) | |
ae0c2d72 | 411 | nvmem_sysfs_remove_compat(nvmem, config); |
3360acdf JH |
412 | err_device_del: |
413 | device_del(&nvmem->dev); | |
414 | err_put_device: | |
415 | put_device(&nvmem->dev); | |
416 | ||
b6c217ab | 417 | return ERR_PTR(rval); |
eace75cf SK |
418 | } |
419 | EXPORT_SYMBOL_GPL(nvmem_register); | |
420 | ||
c1de7f43 BG |
421 | static void nvmem_device_release(struct kref *kref) |
422 | { | |
423 | struct nvmem_device *nvmem; | |
424 | ||
425 | nvmem = container_of(kref, struct nvmem_device, refcnt); | |
426 | ||
bee1138b BG |
427 | blocking_notifier_call_chain(&nvmem_notifier, NVMEM_REMOVE, nvmem); |
428 | ||
c1de7f43 BG |
429 | if (nvmem->flags & FLAG_COMPAT) |
430 | device_remove_bin_file(nvmem->base_dev, &nvmem->eeprom); | |
431 | ||
432 | nvmem_device_remove_all_cells(nvmem); | |
433 | device_del(&nvmem->dev); | |
434 | put_device(&nvmem->dev); | |
435 | } | |
436 | ||
eace75cf SK |
437 | /** |
438 | * nvmem_unregister() - Unregister previously registered nvmem device | |
439 | * | |
440 | * @nvmem: Pointer to previously registered nvmem device. | |
eace75cf | 441 | */ |
bf58e882 | 442 | void nvmem_unregister(struct nvmem_device *nvmem) |
eace75cf | 443 | { |
c1de7f43 | 444 | kref_put(&nvmem->refcnt, nvmem_device_release); |
eace75cf SK |
445 | } |
446 | EXPORT_SYMBOL_GPL(nvmem_unregister); | |
447 | ||
f1f50eca AS |
448 | static void devm_nvmem_release(struct device *dev, void *res) |
449 | { | |
bf58e882 | 450 | nvmem_unregister(*(struct nvmem_device **)res); |
f1f50eca AS |
451 | } |
452 | ||
453 | /** | |
454 | * devm_nvmem_register() - Register a managed nvmem device for given | |
455 | * nvmem_config. | |
456 | * Also creates an binary entry in /sys/bus/nvmem/devices/dev-name/nvmem | |
457 | * | |
b378c779 | 458 | * @dev: Device that uses the nvmem device. |
f1f50eca AS |
459 | * @config: nvmem device configuration with which nvmem device is created. |
460 | * | |
461 | * Return: Will be an ERR_PTR() on error or a valid pointer to nvmem_device | |
462 | * on success. | |
463 | */ | |
464 | struct nvmem_device *devm_nvmem_register(struct device *dev, | |
465 | const struct nvmem_config *config) | |
466 | { | |
467 | struct nvmem_device **ptr, *nvmem; | |
468 | ||
469 | ptr = devres_alloc(devm_nvmem_release, sizeof(*ptr), GFP_KERNEL); | |
470 | if (!ptr) | |
471 | return ERR_PTR(-ENOMEM); | |
472 | ||
473 | nvmem = nvmem_register(config); | |
474 | ||
475 | if (!IS_ERR(nvmem)) { | |
476 | *ptr = nvmem; | |
477 | devres_add(dev, ptr); | |
478 | } else { | |
479 | devres_free(ptr); | |
480 | } | |
481 | ||
482 | return nvmem; | |
483 | } | |
484 | EXPORT_SYMBOL_GPL(devm_nvmem_register); | |
485 | ||
486 | static int devm_nvmem_match(struct device *dev, void *res, void *data) | |
487 | { | |
488 | struct nvmem_device **r = res; | |
489 | ||
490 | return *r == data; | |
491 | } | |
492 | ||
493 | /** | |
494 | * devm_nvmem_unregister() - Unregister previously registered managed nvmem | |
495 | * device. | |
496 | * | |
b378c779 | 497 | * @dev: Device that uses the nvmem device. |
f1f50eca AS |
498 | * @nvmem: Pointer to previously registered nvmem device. |
499 | * | |
500 | * Return: Will be an negative on error or a zero on success. | |
501 | */ | |
502 | int devm_nvmem_unregister(struct device *dev, struct nvmem_device *nvmem) | |
503 | { | |
504 | return devres_release(dev, devm_nvmem_release, devm_nvmem_match, nvmem); | |
505 | } | |
506 | EXPORT_SYMBOL(devm_nvmem_unregister); | |
507 | ||
8c2a2b8c TB |
508 | static struct nvmem_device *__nvmem_device_get(void *data, |
509 | int (*match)(struct device *dev, const void *data)) | |
69aba794 SK |
510 | { |
511 | struct nvmem_device *nvmem = NULL; | |
8c2a2b8c | 512 | struct device *dev; |
69aba794 | 513 | |
c7235ee3 | 514 | mutex_lock(&nvmem_mutex); |
8c2a2b8c TB |
515 | dev = bus_find_device(&nvmem_bus_type, NULL, data, match); |
516 | if (dev) | |
517 | nvmem = to_nvmem_device(dev); | |
69aba794 | 518 | mutex_unlock(&nvmem_mutex); |
c7235ee3 BG |
519 | if (!nvmem) |
520 | return ERR_PTR(-EPROBE_DEFER); | |
69aba794 SK |
521 | |
522 | if (!try_module_get(nvmem->owner)) { | |
523 | dev_err(&nvmem->dev, | |
524 | "could not increase module refcount for cell %s\n", | |
5db652c9 | 525 | nvmem_dev_name(nvmem)); |
69aba794 | 526 | |
73e9dc4d | 527 | put_device(&nvmem->dev); |
69aba794 SK |
528 | return ERR_PTR(-EINVAL); |
529 | } | |
530 | ||
c1de7f43 BG |
531 | kref_get(&nvmem->refcnt); |
532 | ||
69aba794 SK |
533 | return nvmem; |
534 | } | |
535 | ||
536 | static void __nvmem_device_put(struct nvmem_device *nvmem) | |
537 | { | |
73e9dc4d | 538 | put_device(&nvmem->dev); |
69aba794 | 539 | module_put(nvmem->owner); |
c1de7f43 | 540 | kref_put(&nvmem->refcnt, nvmem_device_release); |
69aba794 SK |
541 | } |
542 | ||
e701c67c | 543 | #if IS_ENABLED(CONFIG_OF) |
e2a5402e SK |
544 | /** |
545 | * of_nvmem_device_get() - Get nvmem device from a given id | |
546 | * | |
29143268 | 547 | * @np: Device tree node that uses the nvmem device. |
e2a5402e SK |
548 | * @id: nvmem name from nvmem-names property. |
549 | * | |
550 | * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_device | |
551 | * on success. | |
552 | */ | |
553 | struct nvmem_device *of_nvmem_device_get(struct device_node *np, const char *id) | |
554 | { | |
555 | ||
556 | struct device_node *nvmem_np; | |
d4e7fef1 | 557 | int index = 0; |
e2a5402e | 558 | |
d4e7fef1 AB |
559 | if (id) |
560 | index = of_property_match_string(np, "nvmem-names", id); | |
e2a5402e SK |
561 | |
562 | nvmem_np = of_parse_phandle(np, "nvmem", index); | |
563 | if (!nvmem_np) | |
d4e7fef1 | 564 | return ERR_PTR(-ENOENT); |
e2a5402e | 565 | |
8c2a2b8c | 566 | return __nvmem_device_get(nvmem_np, device_match_of_node); |
e2a5402e SK |
567 | } |
568 | EXPORT_SYMBOL_GPL(of_nvmem_device_get); | |
569 | #endif | |
570 | ||
571 | /** | |
572 | * nvmem_device_get() - Get nvmem device from a given id | |
573 | * | |
29143268 VG |
574 | * @dev: Device that uses the nvmem device. |
575 | * @dev_name: name of the requested nvmem device. | |
e2a5402e SK |
576 | * |
577 | * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_device | |
578 | * on success. | |
579 | */ | |
580 | struct nvmem_device *nvmem_device_get(struct device *dev, const char *dev_name) | |
581 | { | |
582 | if (dev->of_node) { /* try dt first */ | |
583 | struct nvmem_device *nvmem; | |
584 | ||
585 | nvmem = of_nvmem_device_get(dev->of_node, dev_name); | |
586 | ||
587 | if (!IS_ERR(nvmem) || PTR_ERR(nvmem) == -EPROBE_DEFER) | |
588 | return nvmem; | |
589 | ||
590 | } | |
591 | ||
8c2a2b8c | 592 | return __nvmem_device_get((void *)dev_name, device_match_name); |
e2a5402e SK |
593 | } |
594 | EXPORT_SYMBOL_GPL(nvmem_device_get); | |
595 | ||
8c2a2b8c TB |
596 | /** |
597 | * nvmem_device_find() - Find nvmem device with matching function | |
598 | * | |
599 | * @data: Data to pass to match function | |
600 | * @match: Callback function to check device | |
601 | * | |
602 | * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_device | |
603 | * on success. | |
604 | */ | |
605 | struct nvmem_device *nvmem_device_find(void *data, | |
606 | int (*match)(struct device *dev, const void *data)) | |
607 | { | |
608 | return __nvmem_device_get(data, match); | |
609 | } | |
610 | EXPORT_SYMBOL_GPL(nvmem_device_find); | |
611 | ||
e2a5402e SK |
612 | static int devm_nvmem_device_match(struct device *dev, void *res, void *data) |
613 | { | |
614 | struct nvmem_device **nvmem = res; | |
615 | ||
616 | if (WARN_ON(!nvmem || !*nvmem)) | |
617 | return 0; | |
618 | ||
619 | return *nvmem == data; | |
620 | } | |
621 | ||
622 | static void devm_nvmem_device_release(struct device *dev, void *res) | |
623 | { | |
624 | nvmem_device_put(*(struct nvmem_device **)res); | |
625 | } | |
626 | ||
627 | /** | |
628 | * devm_nvmem_device_put() - put alredy got nvmem device | |
629 | * | |
29143268 | 630 | * @dev: Device that uses the nvmem device. |
e2a5402e SK |
631 | * @nvmem: pointer to nvmem device allocated by devm_nvmem_cell_get(), |
632 | * that needs to be released. | |
633 | */ | |
634 | void devm_nvmem_device_put(struct device *dev, struct nvmem_device *nvmem) | |
635 | { | |
636 | int ret; | |
637 | ||
638 | ret = devres_release(dev, devm_nvmem_device_release, | |
639 | devm_nvmem_device_match, nvmem); | |
640 | ||
641 | WARN_ON(ret); | |
642 | } | |
643 | EXPORT_SYMBOL_GPL(devm_nvmem_device_put); | |
644 | ||
645 | /** | |
646 | * nvmem_device_put() - put alredy got nvmem device | |
647 | * | |
648 | * @nvmem: pointer to nvmem device that needs to be released. | |
649 | */ | |
650 | void nvmem_device_put(struct nvmem_device *nvmem) | |
651 | { | |
652 | __nvmem_device_put(nvmem); | |
653 | } | |
654 | EXPORT_SYMBOL_GPL(nvmem_device_put); | |
655 | ||
656 | /** | |
657 | * devm_nvmem_device_get() - Get nvmem cell of device form a given id | |
658 | * | |
29143268 VG |
659 | * @dev: Device that requests the nvmem device. |
660 | * @id: name id for the requested nvmem device. | |
e2a5402e SK |
661 | * |
662 | * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_cell | |
663 | * on success. The nvmem_cell will be freed by the automatically once the | |
664 | * device is freed. | |
665 | */ | |
666 | struct nvmem_device *devm_nvmem_device_get(struct device *dev, const char *id) | |
667 | { | |
668 | struct nvmem_device **ptr, *nvmem; | |
669 | ||
670 | ptr = devres_alloc(devm_nvmem_device_release, sizeof(*ptr), GFP_KERNEL); | |
671 | if (!ptr) | |
672 | return ERR_PTR(-ENOMEM); | |
673 | ||
674 | nvmem = nvmem_device_get(dev, id); | |
675 | if (!IS_ERR(nvmem)) { | |
676 | *ptr = nvmem; | |
677 | devres_add(dev, ptr); | |
678 | } else { | |
679 | devres_free(ptr); | |
680 | } | |
681 | ||
682 | return nvmem; | |
683 | } | |
684 | EXPORT_SYMBOL_GPL(devm_nvmem_device_get); | |
685 | ||
506157be BG |
686 | static struct nvmem_cell * |
687 | nvmem_cell_get_from_lookup(struct device *dev, const char *con_id) | |
69aba794 | 688 | { |
506157be BG |
689 | struct nvmem_cell *cell = ERR_PTR(-ENOENT); |
690 | struct nvmem_cell_lookup *lookup; | |
69aba794 | 691 | struct nvmem_device *nvmem; |
506157be | 692 | const char *dev_id; |
69aba794 | 693 | |
506157be BG |
694 | if (!dev) |
695 | return ERR_PTR(-EINVAL); | |
696 | ||
697 | dev_id = dev_name(dev); | |
698 | ||
699 | mutex_lock(&nvmem_lookup_mutex); | |
700 | ||
701 | list_for_each_entry(lookup, &nvmem_lookup_list, node) { | |
702 | if ((strcmp(lookup->dev_id, dev_id) == 0) && | |
703 | (strcmp(lookup->con_id, con_id) == 0)) { | |
704 | /* This is the right entry. */ | |
8c2a2b8c TB |
705 | nvmem = __nvmem_device_get((void *)lookup->nvmem_name, |
706 | device_match_name); | |
cccb3b19 | 707 | if (IS_ERR(nvmem)) { |
506157be | 708 | /* Provider may not be registered yet. */ |
cccb3b19 | 709 | cell = ERR_CAST(nvmem); |
9bfd8198 | 710 | break; |
506157be BG |
711 | } |
712 | ||
713 | cell = nvmem_find_cell_by_name(nvmem, | |
714 | lookup->cell_name); | |
715 | if (!cell) { | |
716 | __nvmem_device_put(nvmem); | |
cccb3b19 | 717 | cell = ERR_PTR(-ENOENT); |
506157be | 718 | } |
9bfd8198 | 719 | break; |
506157be BG |
720 | } |
721 | } | |
69aba794 | 722 | |
506157be | 723 | mutex_unlock(&nvmem_lookup_mutex); |
69aba794 SK |
724 | return cell; |
725 | } | |
726 | ||
e701c67c | 727 | #if IS_ENABLED(CONFIG_OF) |
3c53e235 | 728 | static struct nvmem_cell * |
0749aa25 | 729 | nvmem_find_cell_by_node(struct nvmem_device *nvmem, struct device_node *np) |
3c53e235 | 730 | { |
1c832674 | 731 | struct nvmem_cell *iter, *cell = NULL; |
3c53e235 AB |
732 | |
733 | mutex_lock(&nvmem_mutex); | |
1c832674 AB |
734 | list_for_each_entry(iter, &nvmem->cells, node) { |
735 | if (np == iter->np) { | |
736 | cell = iter; | |
3c53e235 | 737 | break; |
1c832674 | 738 | } |
3c53e235 AB |
739 | } |
740 | mutex_unlock(&nvmem_mutex); | |
741 | ||
742 | return cell; | |
743 | } | |
744 | ||
69aba794 SK |
745 | /** |
746 | * of_nvmem_cell_get() - Get a nvmem cell from given device node and cell id | |
747 | * | |
29143268 | 748 | * @np: Device tree node that uses the nvmem cell. |
165589f0 BG |
749 | * @id: nvmem cell name from nvmem-cell-names property, or NULL |
750 | * for the cell at index 0 (the lone cell with no accompanying | |
751 | * nvmem-cell-names property). | |
69aba794 SK |
752 | * |
753 | * Return: Will be an ERR_PTR() on error or a valid pointer | |
754 | * to a struct nvmem_cell. The nvmem_cell will be freed by the | |
755 | * nvmem_cell_put(). | |
756 | */ | |
165589f0 | 757 | struct nvmem_cell *of_nvmem_cell_get(struct device_node *np, const char *id) |
69aba794 SK |
758 | { |
759 | struct device_node *cell_np, *nvmem_np; | |
69aba794 | 760 | struct nvmem_device *nvmem; |
e888d445 | 761 | struct nvmem_cell *cell; |
fd0c478c | 762 | int index = 0; |
69aba794 | 763 | |
fd0c478c | 764 | /* if cell name exists, find index to the name */ |
165589f0 BG |
765 | if (id) |
766 | index = of_property_match_string(np, "nvmem-cell-names", id); | |
69aba794 SK |
767 | |
768 | cell_np = of_parse_phandle(np, "nvmem-cells", index); | |
769 | if (!cell_np) | |
5087cc19 | 770 | return ERR_PTR(-ENOENT); |
69aba794 SK |
771 | |
772 | nvmem_np = of_get_next_parent(cell_np); | |
773 | if (!nvmem_np) | |
774 | return ERR_PTR(-EINVAL); | |
775 | ||
8c2a2b8c | 776 | nvmem = __nvmem_device_get(nvmem_np, device_match_of_node); |
aad8d097 | 777 | of_node_put(nvmem_np); |
69aba794 SK |
778 | if (IS_ERR(nvmem)) |
779 | return ERR_CAST(nvmem); | |
780 | ||
0749aa25 | 781 | cell = nvmem_find_cell_by_node(nvmem, cell_np); |
69aba794 | 782 | if (!cell) { |
e888d445 BG |
783 | __nvmem_device_put(nvmem); |
784 | return ERR_PTR(-ENOENT); | |
69aba794 SK |
785 | } |
786 | ||
69aba794 | 787 | return cell; |
69aba794 SK |
788 | } |
789 | EXPORT_SYMBOL_GPL(of_nvmem_cell_get); | |
790 | #endif | |
791 | ||
792 | /** | |
793 | * nvmem_cell_get() - Get nvmem cell of device form a given cell name | |
794 | * | |
29143268 | 795 | * @dev: Device that requests the nvmem cell. |
165589f0 BG |
796 | * @id: nvmem cell name to get (this corresponds with the name from the |
797 | * nvmem-cell-names property for DT systems and with the con_id from | |
798 | * the lookup entry for non-DT systems). | |
69aba794 SK |
799 | * |
800 | * Return: Will be an ERR_PTR() on error or a valid pointer | |
801 | * to a struct nvmem_cell. The nvmem_cell will be freed by the | |
802 | * nvmem_cell_put(). | |
803 | */ | |
165589f0 | 804 | struct nvmem_cell *nvmem_cell_get(struct device *dev, const char *id) |
69aba794 SK |
805 | { |
806 | struct nvmem_cell *cell; | |
807 | ||
808 | if (dev->of_node) { /* try dt first */ | |
165589f0 | 809 | cell = of_nvmem_cell_get(dev->of_node, id); |
69aba794 SK |
810 | if (!IS_ERR(cell) || PTR_ERR(cell) == -EPROBE_DEFER) |
811 | return cell; | |
812 | } | |
813 | ||
165589f0 BG |
814 | /* NULL cell id only allowed for device tree; invalid otherwise */ |
815 | if (!id) | |
87ed1405 DA |
816 | return ERR_PTR(-EINVAL); |
817 | ||
165589f0 | 818 | return nvmem_cell_get_from_lookup(dev, id); |
69aba794 SK |
819 | } |
820 | EXPORT_SYMBOL_GPL(nvmem_cell_get); | |
821 | ||
822 | static void devm_nvmem_cell_release(struct device *dev, void *res) | |
823 | { | |
824 | nvmem_cell_put(*(struct nvmem_cell **)res); | |
825 | } | |
826 | ||
827 | /** | |
828 | * devm_nvmem_cell_get() - Get nvmem cell of device form a given id | |
829 | * | |
29143268 VG |
830 | * @dev: Device that requests the nvmem cell. |
831 | * @id: nvmem cell name id to get. | |
69aba794 SK |
832 | * |
833 | * Return: Will be an ERR_PTR() on error or a valid pointer | |
834 | * to a struct nvmem_cell. The nvmem_cell will be freed by the | |
835 | * automatically once the device is freed. | |
836 | */ | |
837 | struct nvmem_cell *devm_nvmem_cell_get(struct device *dev, const char *id) | |
838 | { | |
839 | struct nvmem_cell **ptr, *cell; | |
840 | ||
841 | ptr = devres_alloc(devm_nvmem_cell_release, sizeof(*ptr), GFP_KERNEL); | |
842 | if (!ptr) | |
843 | return ERR_PTR(-ENOMEM); | |
844 | ||
845 | cell = nvmem_cell_get(dev, id); | |
846 | if (!IS_ERR(cell)) { | |
847 | *ptr = cell; | |
848 | devres_add(dev, ptr); | |
849 | } else { | |
850 | devres_free(ptr); | |
851 | } | |
852 | ||
853 | return cell; | |
854 | } | |
855 | EXPORT_SYMBOL_GPL(devm_nvmem_cell_get); | |
856 | ||
857 | static int devm_nvmem_cell_match(struct device *dev, void *res, void *data) | |
858 | { | |
859 | struct nvmem_cell **c = res; | |
860 | ||
861 | if (WARN_ON(!c || !*c)) | |
862 | return 0; | |
863 | ||
864 | return *c == data; | |
865 | } | |
866 | ||
867 | /** | |
868 | * devm_nvmem_cell_put() - Release previously allocated nvmem cell | |
869 | * from devm_nvmem_cell_get. | |
870 | * | |
29143268 VG |
871 | * @dev: Device that requests the nvmem cell. |
872 | * @cell: Previously allocated nvmem cell by devm_nvmem_cell_get(). | |
69aba794 SK |
873 | */ |
874 | void devm_nvmem_cell_put(struct device *dev, struct nvmem_cell *cell) | |
875 | { | |
876 | int ret; | |
877 | ||
878 | ret = devres_release(dev, devm_nvmem_cell_release, | |
879 | devm_nvmem_cell_match, cell); | |
880 | ||
881 | WARN_ON(ret); | |
882 | } | |
883 | EXPORT_SYMBOL(devm_nvmem_cell_put); | |
884 | ||
885 | /** | |
886 | * nvmem_cell_put() - Release previously allocated nvmem cell. | |
887 | * | |
29143268 | 888 | * @cell: Previously allocated nvmem cell by nvmem_cell_get(). |
69aba794 SK |
889 | */ |
890 | void nvmem_cell_put(struct nvmem_cell *cell) | |
891 | { | |
892 | struct nvmem_device *nvmem = cell->nvmem; | |
893 | ||
894 | __nvmem_device_put(nvmem); | |
69aba794 SK |
895 | } |
896 | EXPORT_SYMBOL_GPL(nvmem_cell_put); | |
897 | ||
f7c04f16 | 898 | static void nvmem_shift_read_buffer_in_place(struct nvmem_cell *cell, void *buf) |
69aba794 SK |
899 | { |
900 | u8 *p, *b; | |
2fe518fe | 901 | int i, extra, bit_offset = cell->bit_offset; |
69aba794 SK |
902 | |
903 | p = b = buf; | |
904 | if (bit_offset) { | |
905 | /* First shift */ | |
906 | *b++ >>= bit_offset; | |
907 | ||
908 | /* setup rest of the bytes if any */ | |
909 | for (i = 1; i < cell->bytes; i++) { | |
910 | /* Get bits from next byte and shift them towards msb */ | |
911 | *p |= *b << (BITS_PER_BYTE - bit_offset); | |
912 | ||
913 | p = b; | |
914 | *b++ >>= bit_offset; | |
915 | } | |
2fe518fe JRO |
916 | } else { |
917 | /* point to the msb */ | |
918 | p += cell->bytes - 1; | |
69aba794 | 919 | } |
2fe518fe JRO |
920 | |
921 | /* result fits in less bytes */ | |
922 | extra = cell->bytes - DIV_ROUND_UP(cell->nbits, BITS_PER_BYTE); | |
923 | while (--extra >= 0) | |
924 | *p-- = 0; | |
925 | ||
69aba794 SK |
926 | /* clear msb bits if any leftover in the last byte */ |
927 | *p &= GENMASK((cell->nbits%BITS_PER_BYTE) - 1, 0); | |
928 | } | |
929 | ||
930 | static int __nvmem_cell_read(struct nvmem_device *nvmem, | |
931 | struct nvmem_cell *cell, | |
932 | void *buf, size_t *len) | |
933 | { | |
934 | int rc; | |
935 | ||
795ddd18 | 936 | rc = nvmem_reg_read(nvmem, cell->offset, buf, cell->bytes); |
69aba794 | 937 | |
287980e4 | 938 | if (rc) |
69aba794 SK |
939 | return rc; |
940 | ||
941 | /* shift bits in-place */ | |
cbf854ab | 942 | if (cell->bit_offset || cell->nbits) |
69aba794 SK |
943 | nvmem_shift_read_buffer_in_place(cell, buf); |
944 | ||
3b4a6877 VG |
945 | if (len) |
946 | *len = cell->bytes; | |
69aba794 SK |
947 | |
948 | return 0; | |
949 | } | |
950 | ||
951 | /** | |
952 | * nvmem_cell_read() - Read a given nvmem cell | |
953 | * | |
954 | * @cell: nvmem cell to be read. | |
3b4a6877 VG |
955 | * @len: pointer to length of cell which will be populated on successful read; |
956 | * can be NULL. | |
69aba794 | 957 | * |
b577fafc BN |
958 | * Return: ERR_PTR() on error or a valid pointer to a buffer on success. The |
959 | * buffer should be freed by the consumer with a kfree(). | |
69aba794 SK |
960 | */ |
961 | void *nvmem_cell_read(struct nvmem_cell *cell, size_t *len) | |
962 | { | |
963 | struct nvmem_device *nvmem = cell->nvmem; | |
964 | u8 *buf; | |
965 | int rc; | |
966 | ||
795ddd18 | 967 | if (!nvmem) |
69aba794 SK |
968 | return ERR_PTR(-EINVAL); |
969 | ||
970 | buf = kzalloc(cell->bytes, GFP_KERNEL); | |
971 | if (!buf) | |
972 | return ERR_PTR(-ENOMEM); | |
973 | ||
974 | rc = __nvmem_cell_read(nvmem, cell, buf, len); | |
287980e4 | 975 | if (rc) { |
69aba794 SK |
976 | kfree(buf); |
977 | return ERR_PTR(rc); | |
978 | } | |
979 | ||
980 | return buf; | |
981 | } | |
982 | EXPORT_SYMBOL_GPL(nvmem_cell_read); | |
983 | ||
f7c04f16 MY |
984 | static void *nvmem_cell_prepare_write_buffer(struct nvmem_cell *cell, |
985 | u8 *_buf, int len) | |
69aba794 SK |
986 | { |
987 | struct nvmem_device *nvmem = cell->nvmem; | |
988 | int i, rc, nbits, bit_offset = cell->bit_offset; | |
989 | u8 v, *p, *buf, *b, pbyte, pbits; | |
990 | ||
991 | nbits = cell->nbits; | |
992 | buf = kzalloc(cell->bytes, GFP_KERNEL); | |
993 | if (!buf) | |
994 | return ERR_PTR(-ENOMEM); | |
995 | ||
996 | memcpy(buf, _buf, len); | |
997 | p = b = buf; | |
998 | ||
999 | if (bit_offset) { | |
1000 | pbyte = *b; | |
1001 | *b <<= bit_offset; | |
1002 | ||
1003 | /* setup the first byte with lsb bits from nvmem */ | |
795ddd18 | 1004 | rc = nvmem_reg_read(nvmem, cell->offset, &v, 1); |
50808bfc MM |
1005 | if (rc) |
1006 | goto err; | |
69aba794 SK |
1007 | *b++ |= GENMASK(bit_offset - 1, 0) & v; |
1008 | ||
1009 | /* setup rest of the byte if any */ | |
1010 | for (i = 1; i < cell->bytes; i++) { | |
1011 | /* Get last byte bits and shift them towards lsb */ | |
1012 | pbits = pbyte >> (BITS_PER_BYTE - 1 - bit_offset); | |
1013 | pbyte = *b; | |
1014 | p = b; | |
1015 | *b <<= bit_offset; | |
1016 | *b++ |= pbits; | |
1017 | } | |
1018 | } | |
1019 | ||
1020 | /* if it's not end on byte boundary */ | |
1021 | if ((nbits + bit_offset) % BITS_PER_BYTE) { | |
1022 | /* setup the last byte with msb bits from nvmem */ | |
795ddd18 | 1023 | rc = nvmem_reg_read(nvmem, |
69aba794 | 1024 | cell->offset + cell->bytes - 1, &v, 1); |
50808bfc MM |
1025 | if (rc) |
1026 | goto err; | |
69aba794 SK |
1027 | *p |= GENMASK(7, (nbits + bit_offset) % BITS_PER_BYTE) & v; |
1028 | ||
1029 | } | |
1030 | ||
1031 | return buf; | |
50808bfc MM |
1032 | err: |
1033 | kfree(buf); | |
1034 | return ERR_PTR(rc); | |
69aba794 SK |
1035 | } |
1036 | ||
1037 | /** | |
1038 | * nvmem_cell_write() - Write to a given nvmem cell | |
1039 | * | |
1040 | * @cell: nvmem cell to be written. | |
1041 | * @buf: Buffer to be written. | |
1042 | * @len: length of buffer to be written to nvmem cell. | |
1043 | * | |
1044 | * Return: length of bytes written or negative on failure. | |
1045 | */ | |
1046 | int nvmem_cell_write(struct nvmem_cell *cell, void *buf, size_t len) | |
1047 | { | |
1048 | struct nvmem_device *nvmem = cell->nvmem; | |
1049 | int rc; | |
1050 | ||
795ddd18 | 1051 | if (!nvmem || nvmem->read_only || |
69aba794 SK |
1052 | (cell->bit_offset == 0 && len != cell->bytes)) |
1053 | return -EINVAL; | |
1054 | ||
1055 | if (cell->bit_offset || cell->nbits) { | |
1056 | buf = nvmem_cell_prepare_write_buffer(cell, buf, len); | |
1057 | if (IS_ERR(buf)) | |
1058 | return PTR_ERR(buf); | |
1059 | } | |
1060 | ||
795ddd18 | 1061 | rc = nvmem_reg_write(nvmem, cell->offset, buf, cell->bytes); |
69aba794 SK |
1062 | |
1063 | /* free the tmp buffer */ | |
ace22170 | 1064 | if (cell->bit_offset || cell->nbits) |
69aba794 SK |
1065 | kfree(buf); |
1066 | ||
287980e4 | 1067 | if (rc) |
69aba794 SK |
1068 | return rc; |
1069 | ||
1070 | return len; | |
1071 | } | |
1072 | EXPORT_SYMBOL_GPL(nvmem_cell_write); | |
1073 | ||
0a9b2d1c FG |
1074 | /** |
1075 | * nvmem_cell_read_u16() - Read a cell value as an u16 | |
1076 | * | |
1077 | * @dev: Device that requests the nvmem cell. | |
1078 | * @cell_id: Name of nvmem cell to read. | |
1079 | * @val: pointer to output value. | |
1080 | * | |
1081 | * Return: 0 on success or negative errno. | |
1082 | */ | |
1083 | int nvmem_cell_read_u16(struct device *dev, const char *cell_id, u16 *val) | |
1084 | { | |
1085 | struct nvmem_cell *cell; | |
1086 | void *buf; | |
1087 | size_t len; | |
1088 | ||
1089 | cell = nvmem_cell_get(dev, cell_id); | |
1090 | if (IS_ERR(cell)) | |
1091 | return PTR_ERR(cell); | |
1092 | ||
1093 | buf = nvmem_cell_read(cell, &len); | |
1094 | if (IS_ERR(buf)) { | |
1095 | nvmem_cell_put(cell); | |
1096 | return PTR_ERR(buf); | |
1097 | } | |
1098 | if (len != sizeof(*val)) { | |
1099 | kfree(buf); | |
1100 | nvmem_cell_put(cell); | |
1101 | return -EINVAL; | |
1102 | } | |
1103 | memcpy(val, buf, sizeof(*val)); | |
1104 | kfree(buf); | |
1105 | nvmem_cell_put(cell); | |
1106 | ||
1107 | return 0; | |
1108 | } | |
1109 | EXPORT_SYMBOL_GPL(nvmem_cell_read_u16); | |
1110 | ||
d026d70a LC |
1111 | /** |
1112 | * nvmem_cell_read_u32() - Read a cell value as an u32 | |
1113 | * | |
1114 | * @dev: Device that requests the nvmem cell. | |
1115 | * @cell_id: Name of nvmem cell to read. | |
1116 | * @val: pointer to output value. | |
1117 | * | |
1118 | * Return: 0 on success or negative errno. | |
1119 | */ | |
1120 | int nvmem_cell_read_u32(struct device *dev, const char *cell_id, u32 *val) | |
1121 | { | |
1122 | struct nvmem_cell *cell; | |
1123 | void *buf; | |
1124 | size_t len; | |
1125 | ||
1126 | cell = nvmem_cell_get(dev, cell_id); | |
1127 | if (IS_ERR(cell)) | |
1128 | return PTR_ERR(cell); | |
1129 | ||
1130 | buf = nvmem_cell_read(cell, &len); | |
1131 | if (IS_ERR(buf)) { | |
1132 | nvmem_cell_put(cell); | |
1133 | return PTR_ERR(buf); | |
1134 | } | |
1135 | if (len != sizeof(*val)) { | |
1136 | kfree(buf); | |
1137 | nvmem_cell_put(cell); | |
1138 | return -EINVAL; | |
1139 | } | |
1140 | memcpy(val, buf, sizeof(*val)); | |
1141 | ||
1142 | kfree(buf); | |
1143 | nvmem_cell_put(cell); | |
1144 | return 0; | |
1145 | } | |
1146 | EXPORT_SYMBOL_GPL(nvmem_cell_read_u32); | |
1147 | ||
e2a5402e SK |
1148 | /** |
1149 | * nvmem_device_cell_read() - Read a given nvmem device and cell | |
1150 | * | |
1151 | * @nvmem: nvmem device to read from. | |
1152 | * @info: nvmem cell info to be read. | |
1153 | * @buf: buffer pointer which will be populated on successful read. | |
1154 | * | |
1155 | * Return: length of successful bytes read on success and negative | |
1156 | * error code on error. | |
1157 | */ | |
1158 | ssize_t nvmem_device_cell_read(struct nvmem_device *nvmem, | |
1159 | struct nvmem_cell_info *info, void *buf) | |
1160 | { | |
1161 | struct nvmem_cell cell; | |
1162 | int rc; | |
1163 | ssize_t len; | |
1164 | ||
795ddd18 | 1165 | if (!nvmem) |
e2a5402e SK |
1166 | return -EINVAL; |
1167 | ||
1168 | rc = nvmem_cell_info_to_nvmem_cell(nvmem, info, &cell); | |
287980e4 | 1169 | if (rc) |
e2a5402e SK |
1170 | return rc; |
1171 | ||
1172 | rc = __nvmem_cell_read(nvmem, &cell, buf, &len); | |
287980e4 | 1173 | if (rc) |
e2a5402e SK |
1174 | return rc; |
1175 | ||
1176 | return len; | |
1177 | } | |
1178 | EXPORT_SYMBOL_GPL(nvmem_device_cell_read); | |
1179 | ||
1180 | /** | |
1181 | * nvmem_device_cell_write() - Write cell to a given nvmem device | |
1182 | * | |
1183 | * @nvmem: nvmem device to be written to. | |
29143268 | 1184 | * @info: nvmem cell info to be written. |
e2a5402e SK |
1185 | * @buf: buffer to be written to cell. |
1186 | * | |
1187 | * Return: length of bytes written or negative error code on failure. | |
48f63a2c | 1188 | */ |
e2a5402e SK |
1189 | int nvmem_device_cell_write(struct nvmem_device *nvmem, |
1190 | struct nvmem_cell_info *info, void *buf) | |
1191 | { | |
1192 | struct nvmem_cell cell; | |
1193 | int rc; | |
1194 | ||
795ddd18 | 1195 | if (!nvmem) |
e2a5402e SK |
1196 | return -EINVAL; |
1197 | ||
1198 | rc = nvmem_cell_info_to_nvmem_cell(nvmem, info, &cell); | |
287980e4 | 1199 | if (rc) |
e2a5402e SK |
1200 | return rc; |
1201 | ||
1202 | return nvmem_cell_write(&cell, buf, cell.bytes); | |
1203 | } | |
1204 | EXPORT_SYMBOL_GPL(nvmem_device_cell_write); | |
1205 | ||
1206 | /** | |
1207 | * nvmem_device_read() - Read from a given nvmem device | |
1208 | * | |
1209 | * @nvmem: nvmem device to read from. | |
1210 | * @offset: offset in nvmem device. | |
1211 | * @bytes: number of bytes to read. | |
1212 | * @buf: buffer pointer which will be populated on successful read. | |
1213 | * | |
1214 | * Return: length of successful bytes read on success and negative | |
1215 | * error code on error. | |
1216 | */ | |
1217 | int nvmem_device_read(struct nvmem_device *nvmem, | |
1218 | unsigned int offset, | |
1219 | size_t bytes, void *buf) | |
1220 | { | |
1221 | int rc; | |
1222 | ||
795ddd18 | 1223 | if (!nvmem) |
e2a5402e SK |
1224 | return -EINVAL; |
1225 | ||
795ddd18 | 1226 | rc = nvmem_reg_read(nvmem, offset, buf, bytes); |
e2a5402e | 1227 | |
287980e4 | 1228 | if (rc) |
e2a5402e SK |
1229 | return rc; |
1230 | ||
1231 | return bytes; | |
1232 | } | |
1233 | EXPORT_SYMBOL_GPL(nvmem_device_read); | |
1234 | ||
1235 | /** | |
1236 | * nvmem_device_write() - Write cell to a given nvmem device | |
1237 | * | |
1238 | * @nvmem: nvmem device to be written to. | |
1239 | * @offset: offset in nvmem device. | |
1240 | * @bytes: number of bytes to write. | |
1241 | * @buf: buffer to be written. | |
1242 | * | |
1243 | * Return: length of bytes written or negative error code on failure. | |
48f63a2c | 1244 | */ |
e2a5402e SK |
1245 | int nvmem_device_write(struct nvmem_device *nvmem, |
1246 | unsigned int offset, | |
1247 | size_t bytes, void *buf) | |
1248 | { | |
1249 | int rc; | |
1250 | ||
795ddd18 | 1251 | if (!nvmem) |
e2a5402e SK |
1252 | return -EINVAL; |
1253 | ||
795ddd18 | 1254 | rc = nvmem_reg_write(nvmem, offset, buf, bytes); |
e2a5402e | 1255 | |
287980e4 | 1256 | if (rc) |
e2a5402e SK |
1257 | return rc; |
1258 | ||
1259 | ||
1260 | return bytes; | |
1261 | } | |
1262 | EXPORT_SYMBOL_GPL(nvmem_device_write); | |
1263 | ||
b985f4cb BG |
1264 | /** |
1265 | * nvmem_add_cell_table() - register a table of cell info entries | |
1266 | * | |
1267 | * @table: table of cell info entries | |
1268 | */ | |
1269 | void nvmem_add_cell_table(struct nvmem_cell_table *table) | |
1270 | { | |
1271 | mutex_lock(&nvmem_cell_mutex); | |
1272 | list_add_tail(&table->node, &nvmem_cell_tables); | |
1273 | mutex_unlock(&nvmem_cell_mutex); | |
1274 | } | |
1275 | EXPORT_SYMBOL_GPL(nvmem_add_cell_table); | |
1276 | ||
1277 | /** | |
1278 | * nvmem_del_cell_table() - remove a previously registered cell info table | |
1279 | * | |
1280 | * @table: table of cell info entries | |
1281 | */ | |
1282 | void nvmem_del_cell_table(struct nvmem_cell_table *table) | |
1283 | { | |
1284 | mutex_lock(&nvmem_cell_mutex); | |
1285 | list_del(&table->node); | |
1286 | mutex_unlock(&nvmem_cell_mutex); | |
1287 | } | |
1288 | EXPORT_SYMBOL_GPL(nvmem_del_cell_table); | |
1289 | ||
506157be BG |
1290 | /** |
1291 | * nvmem_add_cell_lookups() - register a list of cell lookup entries | |
1292 | * | |
1293 | * @entries: array of cell lookup entries | |
1294 | * @nentries: number of cell lookup entries in the array | |
1295 | */ | |
1296 | void nvmem_add_cell_lookups(struct nvmem_cell_lookup *entries, size_t nentries) | |
1297 | { | |
1298 | int i; | |
1299 | ||
1300 | mutex_lock(&nvmem_lookup_mutex); | |
1301 | for (i = 0; i < nentries; i++) | |
1302 | list_add_tail(&entries[i].node, &nvmem_lookup_list); | |
1303 | mutex_unlock(&nvmem_lookup_mutex); | |
1304 | } | |
1305 | EXPORT_SYMBOL_GPL(nvmem_add_cell_lookups); | |
1306 | ||
1307 | /** | |
1308 | * nvmem_del_cell_lookups() - remove a list of previously added cell lookup | |
1309 | * entries | |
1310 | * | |
1311 | * @entries: array of cell lookup entries | |
1312 | * @nentries: number of cell lookup entries in the array | |
1313 | */ | |
1314 | void nvmem_del_cell_lookups(struct nvmem_cell_lookup *entries, size_t nentries) | |
1315 | { | |
1316 | int i; | |
1317 | ||
1318 | mutex_lock(&nvmem_lookup_mutex); | |
1319 | for (i = 0; i < nentries; i++) | |
1320 | list_del(&entries[i].node); | |
1321 | mutex_unlock(&nvmem_lookup_mutex); | |
1322 | } | |
1323 | EXPORT_SYMBOL_GPL(nvmem_del_cell_lookups); | |
1324 | ||
d7b9fd16 BG |
1325 | /** |
1326 | * nvmem_dev_name() - Get the name of a given nvmem device. | |
1327 | * | |
1328 | * @nvmem: nvmem device. | |
1329 | * | |
1330 | * Return: name of the nvmem device. | |
1331 | */ | |
1332 | const char *nvmem_dev_name(struct nvmem_device *nvmem) | |
1333 | { | |
1334 | return dev_name(&nvmem->dev); | |
1335 | } | |
1336 | EXPORT_SYMBOL_GPL(nvmem_dev_name); | |
1337 | ||
eace75cf SK |
1338 | static int __init nvmem_init(void) |
1339 | { | |
1340 | return bus_register(&nvmem_bus_type); | |
1341 | } | |
1342 | ||
1343 | static void __exit nvmem_exit(void) | |
1344 | { | |
1345 | bus_unregister(&nvmem_bus_type); | |
1346 | } | |
1347 | ||
1348 | subsys_initcall(nvmem_init); | |
1349 | module_exit(nvmem_exit); | |
1350 | ||
1351 | MODULE_AUTHOR("Srinivas Kandagatla <srinivas.kandagatla@linaro.org"); | |
1352 | MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com"); | |
1353 | MODULE_DESCRIPTION("nvmem Driver Core"); | |
1354 | MODULE_LICENSE("GPL v2"); |