Commit | Line | Data |
---|---|---|
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> |
ae0c2d72 | 21 | #include "nvmem.h" |
b6c217ab | 22 | |
eace75cf SK |
23 | struct nvmem_cell { |
24 | const char *name; | |
25 | int offset; | |
26 | int bytes; | |
27 | int bit_offset; | |
28 | int nbits; | |
0749aa25 | 29 | struct device_node *np; |
eace75cf SK |
30 | struct nvmem_device *nvmem; |
31 | struct list_head node; | |
32 | }; | |
33 | ||
34 | static DEFINE_MUTEX(nvmem_mutex); | |
35 | static DEFINE_IDA(nvmem_ida); | |
36 | ||
b985f4cb BG |
37 | static DEFINE_MUTEX(nvmem_cell_mutex); |
38 | static LIST_HEAD(nvmem_cell_tables); | |
39 | ||
506157be BG |
40 | static DEFINE_MUTEX(nvmem_lookup_mutex); |
41 | static LIST_HEAD(nvmem_lookup_list); | |
42 | ||
bee1138b BG |
43 | static BLOCKING_NOTIFIER_HEAD(nvmem_notifier); |
44 | ||
b6c217ab | 45 | |
795ddd18 SK |
46 | static int nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset, |
47 | void *val, size_t bytes) | |
48 | { | |
49 | if (nvmem->reg_read) | |
50 | return nvmem->reg_read(nvmem->priv, offset, val, bytes); | |
51 | ||
52 | return -EINVAL; | |
53 | } | |
54 | ||
55 | static int nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset, | |
56 | void *val, size_t bytes) | |
57 | { | |
2a127da4 KT |
58 | int ret; |
59 | ||
60 | if (nvmem->reg_write) { | |
61 | gpiod_set_value_cansleep(nvmem->wp_gpio, 0); | |
62 | ret = nvmem->reg_write(nvmem->priv, offset, val, bytes); | |
63 | gpiod_set_value_cansleep(nvmem->wp_gpio, 1); | |
64 | return ret; | |
65 | } | |
795ddd18 SK |
66 | |
67 | return -EINVAL; | |
68 | } | |
eace75cf | 69 | |
eace75cf SK |
70 | static void nvmem_release(struct device *dev) |
71 | { | |
72 | struct nvmem_device *nvmem = to_nvmem_device(dev); | |
73 | ||
74 | ida_simple_remove(&nvmem_ida, nvmem->id); | |
75 | kfree(nvmem); | |
76 | } | |
77 | ||
78 | static const struct device_type nvmem_provider_type = { | |
79 | .release = nvmem_release, | |
80 | }; | |
81 | ||
82 | static struct bus_type nvmem_bus_type = { | |
83 | .name = "nvmem", | |
84 | }; | |
85 | ||
eace75cf SK |
86 | static void nvmem_cell_drop(struct nvmem_cell *cell) |
87 | { | |
bee1138b | 88 | blocking_notifier_call_chain(&nvmem_notifier, NVMEM_CELL_REMOVE, cell); |
c7235ee3 | 89 | mutex_lock(&nvmem_mutex); |
eace75cf | 90 | list_del(&cell->node); |
c7235ee3 | 91 | mutex_unlock(&nvmem_mutex); |
0749aa25 | 92 | of_node_put(cell->np); |
badcdff1 | 93 | kfree(cell->name); |
eace75cf SK |
94 | kfree(cell); |
95 | } | |
96 | ||
97 | static void nvmem_device_remove_all_cells(const struct nvmem_device *nvmem) | |
98 | { | |
1852183e | 99 | struct nvmem_cell *cell, *p; |
eace75cf | 100 | |
c7235ee3 BG |
101 | list_for_each_entry_safe(cell, p, &nvmem->cells, node) |
102 | nvmem_cell_drop(cell); | |
eace75cf SK |
103 | } |
104 | ||
105 | static void nvmem_cell_add(struct nvmem_cell *cell) | |
106 | { | |
c7235ee3 BG |
107 | mutex_lock(&nvmem_mutex); |
108 | list_add_tail(&cell->node, &cell->nvmem->cells); | |
109 | mutex_unlock(&nvmem_mutex); | |
bee1138b | 110 | blocking_notifier_call_chain(&nvmem_notifier, NVMEM_CELL_ADD, cell); |
eace75cf SK |
111 | } |
112 | ||
113 | static int nvmem_cell_info_to_nvmem_cell(struct nvmem_device *nvmem, | |
114 | const struct nvmem_cell_info *info, | |
115 | struct nvmem_cell *cell) | |
116 | { | |
117 | cell->nvmem = nvmem; | |
118 | cell->offset = info->offset; | |
119 | cell->bytes = info->bytes; | |
120 | cell->name = info->name; | |
121 | ||
122 | cell->bit_offset = info->bit_offset; | |
123 | cell->nbits = info->nbits; | |
124 | ||
125 | if (cell->nbits) | |
126 | cell->bytes = DIV_ROUND_UP(cell->nbits + cell->bit_offset, | |
127 | BITS_PER_BYTE); | |
128 | ||
129 | if (!IS_ALIGNED(cell->offset, nvmem->stride)) { | |
130 | dev_err(&nvmem->dev, | |
131 | "cell %s unaligned to nvmem stride %d\n", | |
132 | cell->name, nvmem->stride); | |
133 | return -EINVAL; | |
134 | } | |
135 | ||
136 | return 0; | |
137 | } | |
138 | ||
b3db17e4 AL |
139 | /** |
140 | * nvmem_add_cells() - Add cell information to an nvmem device | |
141 | * | |
142 | * @nvmem: nvmem device to add cells to. | |
143 | * @info: nvmem cell info to add to the device | |
144 | * @ncells: number of cells in info | |
145 | * | |
146 | * Return: 0 or negative error code on failure. | |
147 | */ | |
ef92ab30 | 148 | static int nvmem_add_cells(struct nvmem_device *nvmem, |
b3db17e4 AL |
149 | const struct nvmem_cell_info *info, |
150 | int ncells) | |
eace75cf SK |
151 | { |
152 | struct nvmem_cell **cells; | |
eace75cf SK |
153 | int i, rval; |
154 | ||
b3db17e4 | 155 | cells = kcalloc(ncells, sizeof(*cells), GFP_KERNEL); |
eace75cf SK |
156 | if (!cells) |
157 | return -ENOMEM; | |
158 | ||
b3db17e4 | 159 | for (i = 0; i < ncells; i++) { |
eace75cf SK |
160 | cells[i] = kzalloc(sizeof(**cells), GFP_KERNEL); |
161 | if (!cells[i]) { | |
162 | rval = -ENOMEM; | |
163 | goto err; | |
164 | } | |
165 | ||
166 | rval = nvmem_cell_info_to_nvmem_cell(nvmem, &info[i], cells[i]); | |
287980e4 | 167 | if (rval) { |
eace75cf SK |
168 | kfree(cells[i]); |
169 | goto err; | |
170 | } | |
171 | ||
172 | nvmem_cell_add(cells[i]); | |
173 | } | |
174 | ||
eace75cf SK |
175 | /* remove tmp array */ |
176 | kfree(cells); | |
177 | ||
178 | return 0; | |
179 | err: | |
dfdf1414 | 180 | while (i--) |
eace75cf SK |
181 | nvmem_cell_drop(cells[i]); |
182 | ||
dfdf1414 RV |
183 | kfree(cells); |
184 | ||
eace75cf SK |
185 | return rval; |
186 | } | |
187 | ||
bee1138b BG |
188 | /** |
189 | * nvmem_register_notifier() - Register a notifier block for nvmem events. | |
190 | * | |
191 | * @nb: notifier block to be called on nvmem events. | |
192 | * | |
193 | * Return: 0 on success, negative error number on failure. | |
194 | */ | |
195 | int nvmem_register_notifier(struct notifier_block *nb) | |
196 | { | |
197 | return blocking_notifier_chain_register(&nvmem_notifier, nb); | |
198 | } | |
199 | EXPORT_SYMBOL_GPL(nvmem_register_notifier); | |
200 | ||
201 | /** | |
202 | * nvmem_unregister_notifier() - Unregister a notifier block for nvmem events. | |
203 | * | |
204 | * @nb: notifier block to be unregistered. | |
205 | * | |
206 | * Return: 0 on success, negative error number on failure. | |
207 | */ | |
208 | int nvmem_unregister_notifier(struct notifier_block *nb) | |
209 | { | |
210 | return blocking_notifier_chain_unregister(&nvmem_notifier, nb); | |
211 | } | |
212 | EXPORT_SYMBOL_GPL(nvmem_unregister_notifier); | |
213 | ||
b985f4cb BG |
214 | static int nvmem_add_cells_from_table(struct nvmem_device *nvmem) |
215 | { | |
216 | const struct nvmem_cell_info *info; | |
217 | struct nvmem_cell_table *table; | |
218 | struct nvmem_cell *cell; | |
219 | int rval = 0, i; | |
220 | ||
221 | mutex_lock(&nvmem_cell_mutex); | |
222 | list_for_each_entry(table, &nvmem_cell_tables, node) { | |
223 | if (strcmp(nvmem_dev_name(nvmem), table->nvmem_name) == 0) { | |
224 | for (i = 0; i < table->ncells; i++) { | |
225 | info = &table->cells[i]; | |
226 | ||
227 | cell = kzalloc(sizeof(*cell), GFP_KERNEL); | |
228 | if (!cell) { | |
229 | rval = -ENOMEM; | |
230 | goto out; | |
231 | } | |
232 | ||
233 | rval = nvmem_cell_info_to_nvmem_cell(nvmem, | |
234 | info, | |
235 | cell); | |
236 | if (rval) { | |
237 | kfree(cell); | |
238 | goto out; | |
239 | } | |
240 | ||
241 | nvmem_cell_add(cell); | |
242 | } | |
243 | } | |
244 | } | |
245 | ||
246 | out: | |
247 | mutex_unlock(&nvmem_cell_mutex); | |
248 | return rval; | |
249 | } | |
250 | ||
506157be BG |
251 | static struct nvmem_cell * |
252 | nvmem_find_cell_by_name(struct nvmem_device *nvmem, const char *cell_id) | |
253 | { | |
1c832674 | 254 | struct nvmem_cell *iter, *cell = NULL; |
506157be BG |
255 | |
256 | mutex_lock(&nvmem_mutex); | |
1c832674 AB |
257 | list_for_each_entry(iter, &nvmem->cells, node) { |
258 | if (strcmp(cell_id, iter->name) == 0) { | |
259 | cell = iter; | |
506157be | 260 | break; |
1c832674 | 261 | } |
506157be BG |
262 | } |
263 | mutex_unlock(&nvmem_mutex); | |
264 | ||
265 | return cell; | |
266 | } | |
267 | ||
e888d445 BG |
268 | static int nvmem_add_cells_from_of(struct nvmem_device *nvmem) |
269 | { | |
270 | struct device_node *parent, *child; | |
271 | struct device *dev = &nvmem->dev; | |
272 | struct nvmem_cell *cell; | |
273 | const __be32 *addr; | |
274 | int len; | |
275 | ||
276 | parent = dev->of_node; | |
277 | ||
278 | for_each_child_of_node(parent, child) { | |
279 | addr = of_get_property(child, "reg", &len); | |
280 | if (!addr || (len < 2 * sizeof(u32))) { | |
281 | dev_err(dev, "nvmem: invalid reg on %pOF\n", child); | |
282 | return -EINVAL; | |
283 | } | |
284 | ||
285 | cell = kzalloc(sizeof(*cell), GFP_KERNEL); | |
286 | if (!cell) | |
287 | return -ENOMEM; | |
288 | ||
289 | cell->nvmem = nvmem; | |
0749aa25 | 290 | cell->np = of_node_get(child); |
e888d445 BG |
291 | cell->offset = be32_to_cpup(addr++); |
292 | cell->bytes = be32_to_cpup(addr); | |
badcdff1 | 293 | cell->name = kasprintf(GFP_KERNEL, "%pOFn", child); |
e888d445 BG |
294 | |
295 | addr = of_get_property(child, "bits", &len); | |
296 | if (addr && len == (2 * sizeof(u32))) { | |
297 | cell->bit_offset = be32_to_cpup(addr++); | |
298 | cell->nbits = be32_to_cpup(addr); | |
299 | } | |
300 | ||
301 | if (cell->nbits) | |
302 | cell->bytes = DIV_ROUND_UP( | |
303 | cell->nbits + cell->bit_offset, | |
304 | BITS_PER_BYTE); | |
305 | ||
306 | if (!IS_ALIGNED(cell->offset, nvmem->stride)) { | |
307 | dev_err(dev, "cell %s unaligned to nvmem stride %d\n", | |
308 | cell->name, nvmem->stride); | |
309 | /* Cells already added will be freed later. */ | |
badcdff1 | 310 | kfree(cell->name); |
e888d445 BG |
311 | kfree(cell); |
312 | return -EINVAL; | |
313 | } | |
314 | ||
315 | nvmem_cell_add(cell); | |
316 | } | |
317 | ||
318 | return 0; | |
319 | } | |
320 | ||
eace75cf SK |
321 | /** |
322 | * nvmem_register() - Register a nvmem device for given nvmem_config. | |
323 | * Also creates an binary entry in /sys/bus/nvmem/devices/dev-name/nvmem | |
324 | * | |
325 | * @config: nvmem device configuration with which nvmem device is created. | |
326 | * | |
327 | * Return: Will be an ERR_PTR() on error or a valid pointer to nvmem_device | |
328 | * on success. | |
329 | */ | |
330 | ||
331 | struct nvmem_device *nvmem_register(const struct nvmem_config *config) | |
332 | { | |
333 | struct nvmem_device *nvmem; | |
eace75cf SK |
334 | int rval; |
335 | ||
336 | if (!config->dev) | |
337 | return ERR_PTR(-EINVAL); | |
338 | ||
eace75cf SK |
339 | nvmem = kzalloc(sizeof(*nvmem), GFP_KERNEL); |
340 | if (!nvmem) | |
341 | return ERR_PTR(-ENOMEM); | |
342 | ||
343 | rval = ida_simple_get(&nvmem_ida, 0, 0, GFP_KERNEL); | |
344 | if (rval < 0) { | |
345 | kfree(nvmem); | |
346 | return ERR_PTR(rval); | |
347 | } | |
2a127da4 KT |
348 | if (config->wp_gpio) |
349 | nvmem->wp_gpio = config->wp_gpio; | |
350 | else | |
351 | nvmem->wp_gpio = gpiod_get_optional(config->dev, "wp", | |
352 | GPIOD_OUT_HIGH); | |
353 | if (IS_ERR(nvmem->wp_gpio)) | |
a99d2c6c | 354 | return ERR_CAST(nvmem->wp_gpio); |
2a127da4 | 355 | |
eace75cf | 356 | |
c1de7f43 | 357 | kref_init(&nvmem->refcnt); |
c7235ee3 | 358 | INIT_LIST_HEAD(&nvmem->cells); |
c1de7f43 | 359 | |
eace75cf | 360 | nvmem->id = rval; |
eace75cf | 361 | nvmem->owner = config->owner; |
17eb18d6 MY |
362 | if (!nvmem->owner && config->dev->driver) |
363 | nvmem->owner = config->dev->driver->owner; | |
99897efd HK |
364 | nvmem->stride = config->stride ?: 1; |
365 | nvmem->word_size = config->word_size ?: 1; | |
795ddd18 | 366 | nvmem->size = config->size; |
eace75cf SK |
367 | nvmem->dev.type = &nvmem_provider_type; |
368 | nvmem->dev.bus = &nvmem_bus_type; | |
369 | nvmem->dev.parent = config->dev; | |
795ddd18 | 370 | nvmem->priv = config->priv; |
16688453 | 371 | nvmem->type = config->type; |
795ddd18 SK |
372 | nvmem->reg_read = config->reg_read; |
373 | nvmem->reg_write = config->reg_write; | |
517f14d9 BG |
374 | if (!config->no_of_node) |
375 | nvmem->dev.of_node = config->dev->of_node; | |
fd0f4906 AS |
376 | |
377 | if (config->id == -1 && config->name) { | |
378 | dev_set_name(&nvmem->dev, "%s", config->name); | |
379 | } else { | |
380 | dev_set_name(&nvmem->dev, "%s%d", | |
381 | config->name ? : "nvmem", | |
382 | config->name ? config->id : nvmem->id); | |
383 | } | |
eace75cf | 384 | |
1716cfe8 AB |
385 | nvmem->read_only = device_property_present(config->dev, "read-only") || |
386 | config->read_only || !nvmem->reg_write; | |
eace75cf | 387 | |
ae0c2d72 | 388 | nvmem->dev.groups = nvmem_sysfs_get_groups(nvmem, config); |
eace75cf SK |
389 | |
390 | device_initialize(&nvmem->dev); | |
391 | ||
392 | dev_dbg(&nvmem->dev, "Registering nvmem device %s\n", config->name); | |
393 | ||
394 | rval = device_add(&nvmem->dev); | |
b6c217ab | 395 | if (rval) |
3360acdf | 396 | goto err_put_device; |
b6c217ab AL |
397 | |
398 | if (config->compat) { | |
ae0c2d72 | 399 | rval = nvmem_sysfs_setup_compat(nvmem, config); |
b6c217ab | 400 | if (rval) |
3360acdf | 401 | goto err_device_del; |
eace75cf SK |
402 | } |
403 | ||
fa72d847 BG |
404 | if (config->cells) { |
405 | rval = nvmem_add_cells(nvmem, config->cells, config->ncells); | |
406 | if (rval) | |
407 | goto err_teardown_compat; | |
408 | } | |
eace75cf | 409 | |
b985f4cb BG |
410 | rval = nvmem_add_cells_from_table(nvmem); |
411 | if (rval) | |
412 | goto err_remove_cells; | |
413 | ||
e888d445 BG |
414 | rval = nvmem_add_cells_from_of(nvmem); |
415 | if (rval) | |
416 | goto err_remove_cells; | |
417 | ||
f4853e1c | 418 | blocking_notifier_call_chain(&nvmem_notifier, NVMEM_ADD, nvmem); |
bee1138b | 419 | |
eace75cf | 420 | return nvmem; |
3360acdf | 421 | |
b985f4cb BG |
422 | err_remove_cells: |
423 | nvmem_device_remove_all_cells(nvmem); | |
fa72d847 BG |
424 | err_teardown_compat: |
425 | if (config->compat) | |
ae0c2d72 | 426 | nvmem_sysfs_remove_compat(nvmem, config); |
3360acdf JH |
427 | err_device_del: |
428 | device_del(&nvmem->dev); | |
429 | err_put_device: | |
430 | put_device(&nvmem->dev); | |
431 | ||
b6c217ab | 432 | return ERR_PTR(rval); |
eace75cf SK |
433 | } |
434 | EXPORT_SYMBOL_GPL(nvmem_register); | |
435 | ||
c1de7f43 BG |
436 | static void nvmem_device_release(struct kref *kref) |
437 | { | |
438 | struct nvmem_device *nvmem; | |
439 | ||
440 | nvmem = container_of(kref, struct nvmem_device, refcnt); | |
441 | ||
bee1138b BG |
442 | blocking_notifier_call_chain(&nvmem_notifier, NVMEM_REMOVE, nvmem); |
443 | ||
c1de7f43 BG |
444 | if (nvmem->flags & FLAG_COMPAT) |
445 | device_remove_bin_file(nvmem->base_dev, &nvmem->eeprom); | |
446 | ||
447 | nvmem_device_remove_all_cells(nvmem); | |
448 | device_del(&nvmem->dev); | |
449 | put_device(&nvmem->dev); | |
450 | } | |
451 | ||
eace75cf SK |
452 | /** |
453 | * nvmem_unregister() - Unregister previously registered nvmem device | |
454 | * | |
455 | * @nvmem: Pointer to previously registered nvmem device. | |
eace75cf | 456 | */ |
bf58e882 | 457 | void nvmem_unregister(struct nvmem_device *nvmem) |
eace75cf | 458 | { |
c1de7f43 | 459 | kref_put(&nvmem->refcnt, nvmem_device_release); |
eace75cf SK |
460 | } |
461 | EXPORT_SYMBOL_GPL(nvmem_unregister); | |
462 | ||
f1f50eca AS |
463 | static void devm_nvmem_release(struct device *dev, void *res) |
464 | { | |
bf58e882 | 465 | nvmem_unregister(*(struct nvmem_device **)res); |
f1f50eca AS |
466 | } |
467 | ||
468 | /** | |
469 | * devm_nvmem_register() - Register a managed nvmem device for given | |
470 | * nvmem_config. | |
471 | * Also creates an binary entry in /sys/bus/nvmem/devices/dev-name/nvmem | |
472 | * | |
b378c779 | 473 | * @dev: Device that uses the nvmem device. |
f1f50eca AS |
474 | * @config: nvmem device configuration with which nvmem device is created. |
475 | * | |
476 | * Return: Will be an ERR_PTR() on error or a valid pointer to nvmem_device | |
477 | * on success. | |
478 | */ | |
479 | struct nvmem_device *devm_nvmem_register(struct device *dev, | |
480 | const struct nvmem_config *config) | |
481 | { | |
482 | struct nvmem_device **ptr, *nvmem; | |
483 | ||
484 | ptr = devres_alloc(devm_nvmem_release, sizeof(*ptr), GFP_KERNEL); | |
485 | if (!ptr) | |
486 | return ERR_PTR(-ENOMEM); | |
487 | ||
488 | nvmem = nvmem_register(config); | |
489 | ||
490 | if (!IS_ERR(nvmem)) { | |
491 | *ptr = nvmem; | |
492 | devres_add(dev, ptr); | |
493 | } else { | |
494 | devres_free(ptr); | |
495 | } | |
496 | ||
497 | return nvmem; | |
498 | } | |
499 | EXPORT_SYMBOL_GPL(devm_nvmem_register); | |
500 | ||
501 | static int devm_nvmem_match(struct device *dev, void *res, void *data) | |
502 | { | |
503 | struct nvmem_device **r = res; | |
504 | ||
505 | return *r == data; | |
506 | } | |
507 | ||
508 | /** | |
509 | * devm_nvmem_unregister() - Unregister previously registered managed nvmem | |
510 | * device. | |
511 | * | |
b378c779 | 512 | * @dev: Device that uses the nvmem device. |
f1f50eca AS |
513 | * @nvmem: Pointer to previously registered nvmem device. |
514 | * | |
515 | * Return: Will be an negative on error or a zero on success. | |
516 | */ | |
517 | int devm_nvmem_unregister(struct device *dev, struct nvmem_device *nvmem) | |
518 | { | |
519 | return devres_release(dev, devm_nvmem_release, devm_nvmem_match, nvmem); | |
520 | } | |
521 | EXPORT_SYMBOL(devm_nvmem_unregister); | |
522 | ||
8c2a2b8c TB |
523 | static struct nvmem_device *__nvmem_device_get(void *data, |
524 | int (*match)(struct device *dev, const void *data)) | |
69aba794 SK |
525 | { |
526 | struct nvmem_device *nvmem = NULL; | |
8c2a2b8c | 527 | struct device *dev; |
69aba794 | 528 | |
c7235ee3 | 529 | mutex_lock(&nvmem_mutex); |
8c2a2b8c TB |
530 | dev = bus_find_device(&nvmem_bus_type, NULL, data, match); |
531 | if (dev) | |
532 | nvmem = to_nvmem_device(dev); | |
69aba794 | 533 | mutex_unlock(&nvmem_mutex); |
c7235ee3 BG |
534 | if (!nvmem) |
535 | return ERR_PTR(-EPROBE_DEFER); | |
69aba794 SK |
536 | |
537 | if (!try_module_get(nvmem->owner)) { | |
538 | dev_err(&nvmem->dev, | |
539 | "could not increase module refcount for cell %s\n", | |
5db652c9 | 540 | nvmem_dev_name(nvmem)); |
69aba794 | 541 | |
73e9dc4d | 542 | put_device(&nvmem->dev); |
69aba794 SK |
543 | return ERR_PTR(-EINVAL); |
544 | } | |
545 | ||
c1de7f43 BG |
546 | kref_get(&nvmem->refcnt); |
547 | ||
69aba794 SK |
548 | return nvmem; |
549 | } | |
550 | ||
551 | static void __nvmem_device_put(struct nvmem_device *nvmem) | |
552 | { | |
73e9dc4d | 553 | put_device(&nvmem->dev); |
69aba794 | 554 | module_put(nvmem->owner); |
c1de7f43 | 555 | kref_put(&nvmem->refcnt, nvmem_device_release); |
69aba794 SK |
556 | } |
557 | ||
e701c67c | 558 | #if IS_ENABLED(CONFIG_OF) |
e2a5402e SK |
559 | /** |
560 | * of_nvmem_device_get() - Get nvmem device from a given id | |
561 | * | |
29143268 | 562 | * @np: Device tree node that uses the nvmem device. |
e2a5402e SK |
563 | * @id: nvmem name from nvmem-names property. |
564 | * | |
565 | * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_device | |
566 | * on success. | |
567 | */ | |
568 | struct nvmem_device *of_nvmem_device_get(struct device_node *np, const char *id) | |
569 | { | |
570 | ||
571 | struct device_node *nvmem_np; | |
d4e7fef1 | 572 | int index = 0; |
e2a5402e | 573 | |
d4e7fef1 AB |
574 | if (id) |
575 | index = of_property_match_string(np, "nvmem-names", id); | |
e2a5402e SK |
576 | |
577 | nvmem_np = of_parse_phandle(np, "nvmem", index); | |
578 | if (!nvmem_np) | |
d4e7fef1 | 579 | return ERR_PTR(-ENOENT); |
e2a5402e | 580 | |
8c2a2b8c | 581 | return __nvmem_device_get(nvmem_np, device_match_of_node); |
e2a5402e SK |
582 | } |
583 | EXPORT_SYMBOL_GPL(of_nvmem_device_get); | |
584 | #endif | |
585 | ||
586 | /** | |
587 | * nvmem_device_get() - Get nvmem device from a given id | |
588 | * | |
29143268 VG |
589 | * @dev: Device that uses the nvmem device. |
590 | * @dev_name: name of the requested nvmem device. | |
e2a5402e SK |
591 | * |
592 | * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_device | |
593 | * on success. | |
594 | */ | |
595 | struct nvmem_device *nvmem_device_get(struct device *dev, const char *dev_name) | |
596 | { | |
597 | if (dev->of_node) { /* try dt first */ | |
598 | struct nvmem_device *nvmem; | |
599 | ||
600 | nvmem = of_nvmem_device_get(dev->of_node, dev_name); | |
601 | ||
602 | if (!IS_ERR(nvmem) || PTR_ERR(nvmem) == -EPROBE_DEFER) | |
603 | return nvmem; | |
604 | ||
605 | } | |
606 | ||
8c2a2b8c | 607 | return __nvmem_device_get((void *)dev_name, device_match_name); |
e2a5402e SK |
608 | } |
609 | EXPORT_SYMBOL_GPL(nvmem_device_get); | |
610 | ||
8c2a2b8c TB |
611 | /** |
612 | * nvmem_device_find() - Find nvmem device with matching function | |
613 | * | |
614 | * @data: Data to pass to match function | |
615 | * @match: Callback function to check device | |
616 | * | |
617 | * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_device | |
618 | * on success. | |
619 | */ | |
620 | struct nvmem_device *nvmem_device_find(void *data, | |
621 | int (*match)(struct device *dev, const void *data)) | |
622 | { | |
623 | return __nvmem_device_get(data, match); | |
624 | } | |
625 | EXPORT_SYMBOL_GPL(nvmem_device_find); | |
626 | ||
e2a5402e SK |
627 | static int devm_nvmem_device_match(struct device *dev, void *res, void *data) |
628 | { | |
629 | struct nvmem_device **nvmem = res; | |
630 | ||
631 | if (WARN_ON(!nvmem || !*nvmem)) | |
632 | return 0; | |
633 | ||
634 | return *nvmem == data; | |
635 | } | |
636 | ||
637 | static void devm_nvmem_device_release(struct device *dev, void *res) | |
638 | { | |
639 | nvmem_device_put(*(struct nvmem_device **)res); | |
640 | } | |
641 | ||
642 | /** | |
643 | * devm_nvmem_device_put() - put alredy got nvmem device | |
644 | * | |
29143268 | 645 | * @dev: Device that uses the nvmem device. |
e2a5402e SK |
646 | * @nvmem: pointer to nvmem device allocated by devm_nvmem_cell_get(), |
647 | * that needs to be released. | |
648 | */ | |
649 | void devm_nvmem_device_put(struct device *dev, struct nvmem_device *nvmem) | |
650 | { | |
651 | int ret; | |
652 | ||
653 | ret = devres_release(dev, devm_nvmem_device_release, | |
654 | devm_nvmem_device_match, nvmem); | |
655 | ||
656 | WARN_ON(ret); | |
657 | } | |
658 | EXPORT_SYMBOL_GPL(devm_nvmem_device_put); | |
659 | ||
660 | /** | |
661 | * nvmem_device_put() - put alredy got nvmem device | |
662 | * | |
663 | * @nvmem: pointer to nvmem device that needs to be released. | |
664 | */ | |
665 | void nvmem_device_put(struct nvmem_device *nvmem) | |
666 | { | |
667 | __nvmem_device_put(nvmem); | |
668 | } | |
669 | EXPORT_SYMBOL_GPL(nvmem_device_put); | |
670 | ||
671 | /** | |
672 | * devm_nvmem_device_get() - Get nvmem cell of device form a given id | |
673 | * | |
29143268 VG |
674 | * @dev: Device that requests the nvmem device. |
675 | * @id: name id for the requested nvmem device. | |
e2a5402e SK |
676 | * |
677 | * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_cell | |
678 | * on success. The nvmem_cell will be freed by the automatically once the | |
679 | * device is freed. | |
680 | */ | |
681 | struct nvmem_device *devm_nvmem_device_get(struct device *dev, const char *id) | |
682 | { | |
683 | struct nvmem_device **ptr, *nvmem; | |
684 | ||
685 | ptr = devres_alloc(devm_nvmem_device_release, sizeof(*ptr), GFP_KERNEL); | |
686 | if (!ptr) | |
687 | return ERR_PTR(-ENOMEM); | |
688 | ||
689 | nvmem = nvmem_device_get(dev, id); | |
690 | if (!IS_ERR(nvmem)) { | |
691 | *ptr = nvmem; | |
692 | devres_add(dev, ptr); | |
693 | } else { | |
694 | devres_free(ptr); | |
695 | } | |
696 | ||
697 | return nvmem; | |
698 | } | |
699 | EXPORT_SYMBOL_GPL(devm_nvmem_device_get); | |
700 | ||
506157be BG |
701 | static struct nvmem_cell * |
702 | nvmem_cell_get_from_lookup(struct device *dev, const char *con_id) | |
69aba794 | 703 | { |
506157be BG |
704 | struct nvmem_cell *cell = ERR_PTR(-ENOENT); |
705 | struct nvmem_cell_lookup *lookup; | |
69aba794 | 706 | struct nvmem_device *nvmem; |
506157be | 707 | const char *dev_id; |
69aba794 | 708 | |
506157be BG |
709 | if (!dev) |
710 | return ERR_PTR(-EINVAL); | |
711 | ||
712 | dev_id = dev_name(dev); | |
713 | ||
714 | mutex_lock(&nvmem_lookup_mutex); | |
715 | ||
716 | list_for_each_entry(lookup, &nvmem_lookup_list, node) { | |
717 | if ((strcmp(lookup->dev_id, dev_id) == 0) && | |
718 | (strcmp(lookup->con_id, con_id) == 0)) { | |
719 | /* This is the right entry. */ | |
8c2a2b8c TB |
720 | nvmem = __nvmem_device_get((void *)lookup->nvmem_name, |
721 | device_match_name); | |
cccb3b19 | 722 | if (IS_ERR(nvmem)) { |
506157be | 723 | /* Provider may not be registered yet. */ |
cccb3b19 | 724 | cell = ERR_CAST(nvmem); |
9bfd8198 | 725 | break; |
506157be BG |
726 | } |
727 | ||
728 | cell = nvmem_find_cell_by_name(nvmem, | |
729 | lookup->cell_name); | |
730 | if (!cell) { | |
731 | __nvmem_device_put(nvmem); | |
cccb3b19 | 732 | cell = ERR_PTR(-ENOENT); |
506157be | 733 | } |
9bfd8198 | 734 | break; |
506157be BG |
735 | } |
736 | } | |
69aba794 | 737 | |
506157be | 738 | mutex_unlock(&nvmem_lookup_mutex); |
69aba794 SK |
739 | return cell; |
740 | } | |
741 | ||
e701c67c | 742 | #if IS_ENABLED(CONFIG_OF) |
3c53e235 | 743 | static struct nvmem_cell * |
0749aa25 | 744 | nvmem_find_cell_by_node(struct nvmem_device *nvmem, struct device_node *np) |
3c53e235 | 745 | { |
1c832674 | 746 | struct nvmem_cell *iter, *cell = NULL; |
3c53e235 AB |
747 | |
748 | mutex_lock(&nvmem_mutex); | |
1c832674 AB |
749 | list_for_each_entry(iter, &nvmem->cells, node) { |
750 | if (np == iter->np) { | |
751 | cell = iter; | |
3c53e235 | 752 | break; |
1c832674 | 753 | } |
3c53e235 AB |
754 | } |
755 | mutex_unlock(&nvmem_mutex); | |
756 | ||
757 | return cell; | |
758 | } | |
759 | ||
69aba794 SK |
760 | /** |
761 | * of_nvmem_cell_get() - Get a nvmem cell from given device node and cell id | |
762 | * | |
29143268 | 763 | * @np: Device tree node that uses the nvmem cell. |
165589f0 BG |
764 | * @id: nvmem cell name from nvmem-cell-names property, or NULL |
765 | * for the cell at index 0 (the lone cell with no accompanying | |
766 | * nvmem-cell-names property). | |
69aba794 SK |
767 | * |
768 | * Return: Will be an ERR_PTR() on error or a valid pointer | |
769 | * to a struct nvmem_cell. The nvmem_cell will be freed by the | |
770 | * nvmem_cell_put(). | |
771 | */ | |
165589f0 | 772 | struct nvmem_cell *of_nvmem_cell_get(struct device_node *np, const char *id) |
69aba794 SK |
773 | { |
774 | struct device_node *cell_np, *nvmem_np; | |
69aba794 | 775 | struct nvmem_device *nvmem; |
e888d445 | 776 | struct nvmem_cell *cell; |
fd0c478c | 777 | int index = 0; |
69aba794 | 778 | |
fd0c478c | 779 | /* if cell name exists, find index to the name */ |
165589f0 BG |
780 | if (id) |
781 | index = of_property_match_string(np, "nvmem-cell-names", id); | |
69aba794 SK |
782 | |
783 | cell_np = of_parse_phandle(np, "nvmem-cells", index); | |
784 | if (!cell_np) | |
5087cc19 | 785 | return ERR_PTR(-ENOENT); |
69aba794 SK |
786 | |
787 | nvmem_np = of_get_next_parent(cell_np); | |
788 | if (!nvmem_np) | |
789 | return ERR_PTR(-EINVAL); | |
790 | ||
8c2a2b8c | 791 | nvmem = __nvmem_device_get(nvmem_np, device_match_of_node); |
aad8d097 | 792 | of_node_put(nvmem_np); |
69aba794 SK |
793 | if (IS_ERR(nvmem)) |
794 | return ERR_CAST(nvmem); | |
795 | ||
0749aa25 | 796 | cell = nvmem_find_cell_by_node(nvmem, cell_np); |
69aba794 | 797 | if (!cell) { |
e888d445 BG |
798 | __nvmem_device_put(nvmem); |
799 | return ERR_PTR(-ENOENT); | |
69aba794 SK |
800 | } |
801 | ||
69aba794 | 802 | return cell; |
69aba794 SK |
803 | } |
804 | EXPORT_SYMBOL_GPL(of_nvmem_cell_get); | |
805 | #endif | |
806 | ||
807 | /** | |
808 | * nvmem_cell_get() - Get nvmem cell of device form a given cell name | |
809 | * | |
29143268 | 810 | * @dev: Device that requests the nvmem cell. |
165589f0 BG |
811 | * @id: nvmem cell name to get (this corresponds with the name from the |
812 | * nvmem-cell-names property for DT systems and with the con_id from | |
813 | * the lookup entry for non-DT systems). | |
69aba794 SK |
814 | * |
815 | * Return: Will be an ERR_PTR() on error or a valid pointer | |
816 | * to a struct nvmem_cell. The nvmem_cell will be freed by the | |
817 | * nvmem_cell_put(). | |
818 | */ | |
165589f0 | 819 | struct nvmem_cell *nvmem_cell_get(struct device *dev, const char *id) |
69aba794 SK |
820 | { |
821 | struct nvmem_cell *cell; | |
822 | ||
823 | if (dev->of_node) { /* try dt first */ | |
165589f0 | 824 | cell = of_nvmem_cell_get(dev->of_node, id); |
69aba794 SK |
825 | if (!IS_ERR(cell) || PTR_ERR(cell) == -EPROBE_DEFER) |
826 | return cell; | |
827 | } | |
828 | ||
165589f0 BG |
829 | /* NULL cell id only allowed for device tree; invalid otherwise */ |
830 | if (!id) | |
87ed1405 DA |
831 | return ERR_PTR(-EINVAL); |
832 | ||
165589f0 | 833 | return nvmem_cell_get_from_lookup(dev, id); |
69aba794 SK |
834 | } |
835 | EXPORT_SYMBOL_GPL(nvmem_cell_get); | |
836 | ||
837 | static void devm_nvmem_cell_release(struct device *dev, void *res) | |
838 | { | |
839 | nvmem_cell_put(*(struct nvmem_cell **)res); | |
840 | } | |
841 | ||
842 | /** | |
843 | * devm_nvmem_cell_get() - Get nvmem cell of device form a given id | |
844 | * | |
29143268 VG |
845 | * @dev: Device that requests the nvmem cell. |
846 | * @id: nvmem cell name id to get. | |
69aba794 SK |
847 | * |
848 | * Return: Will be an ERR_PTR() on error or a valid pointer | |
849 | * to a struct nvmem_cell. The nvmem_cell will be freed by the | |
850 | * automatically once the device is freed. | |
851 | */ | |
852 | struct nvmem_cell *devm_nvmem_cell_get(struct device *dev, const char *id) | |
853 | { | |
854 | struct nvmem_cell **ptr, *cell; | |
855 | ||
856 | ptr = devres_alloc(devm_nvmem_cell_release, sizeof(*ptr), GFP_KERNEL); | |
857 | if (!ptr) | |
858 | return ERR_PTR(-ENOMEM); | |
859 | ||
860 | cell = nvmem_cell_get(dev, id); | |
861 | if (!IS_ERR(cell)) { | |
862 | *ptr = cell; | |
863 | devres_add(dev, ptr); | |
864 | } else { | |
865 | devres_free(ptr); | |
866 | } | |
867 | ||
868 | return cell; | |
869 | } | |
870 | EXPORT_SYMBOL_GPL(devm_nvmem_cell_get); | |
871 | ||
872 | static int devm_nvmem_cell_match(struct device *dev, void *res, void *data) | |
873 | { | |
874 | struct nvmem_cell **c = res; | |
875 | ||
876 | if (WARN_ON(!c || !*c)) | |
877 | return 0; | |
878 | ||
879 | return *c == data; | |
880 | } | |
881 | ||
882 | /** | |
883 | * devm_nvmem_cell_put() - Release previously allocated nvmem cell | |
884 | * from devm_nvmem_cell_get. | |
885 | * | |
29143268 VG |
886 | * @dev: Device that requests the nvmem cell. |
887 | * @cell: Previously allocated nvmem cell by devm_nvmem_cell_get(). | |
69aba794 SK |
888 | */ |
889 | void devm_nvmem_cell_put(struct device *dev, struct nvmem_cell *cell) | |
890 | { | |
891 | int ret; | |
892 | ||
893 | ret = devres_release(dev, devm_nvmem_cell_release, | |
894 | devm_nvmem_cell_match, cell); | |
895 | ||
896 | WARN_ON(ret); | |
897 | } | |
898 | EXPORT_SYMBOL(devm_nvmem_cell_put); | |
899 | ||
900 | /** | |
901 | * nvmem_cell_put() - Release previously allocated nvmem cell. | |
902 | * | |
29143268 | 903 | * @cell: Previously allocated nvmem cell by nvmem_cell_get(). |
69aba794 SK |
904 | */ |
905 | void nvmem_cell_put(struct nvmem_cell *cell) | |
906 | { | |
907 | struct nvmem_device *nvmem = cell->nvmem; | |
908 | ||
909 | __nvmem_device_put(nvmem); | |
69aba794 SK |
910 | } |
911 | EXPORT_SYMBOL_GPL(nvmem_cell_put); | |
912 | ||
f7c04f16 | 913 | static void nvmem_shift_read_buffer_in_place(struct nvmem_cell *cell, void *buf) |
69aba794 SK |
914 | { |
915 | u8 *p, *b; | |
2fe518fe | 916 | int i, extra, bit_offset = cell->bit_offset; |
69aba794 SK |
917 | |
918 | p = b = buf; | |
919 | if (bit_offset) { | |
920 | /* First shift */ | |
921 | *b++ >>= bit_offset; | |
922 | ||
923 | /* setup rest of the bytes if any */ | |
924 | for (i = 1; i < cell->bytes; i++) { | |
925 | /* Get bits from next byte and shift them towards msb */ | |
926 | *p |= *b << (BITS_PER_BYTE - bit_offset); | |
927 | ||
928 | p = b; | |
929 | *b++ >>= bit_offset; | |
930 | } | |
2fe518fe JRO |
931 | } else { |
932 | /* point to the msb */ | |
933 | p += cell->bytes - 1; | |
69aba794 | 934 | } |
2fe518fe JRO |
935 | |
936 | /* result fits in less bytes */ | |
937 | extra = cell->bytes - DIV_ROUND_UP(cell->nbits, BITS_PER_BYTE); | |
938 | while (--extra >= 0) | |
939 | *p-- = 0; | |
940 | ||
69aba794 SK |
941 | /* clear msb bits if any leftover in the last byte */ |
942 | *p &= GENMASK((cell->nbits%BITS_PER_BYTE) - 1, 0); | |
943 | } | |
944 | ||
945 | static int __nvmem_cell_read(struct nvmem_device *nvmem, | |
946 | struct nvmem_cell *cell, | |
947 | void *buf, size_t *len) | |
948 | { | |
949 | int rc; | |
950 | ||
795ddd18 | 951 | rc = nvmem_reg_read(nvmem, cell->offset, buf, cell->bytes); |
69aba794 | 952 | |
287980e4 | 953 | if (rc) |
69aba794 SK |
954 | return rc; |
955 | ||
956 | /* shift bits in-place */ | |
cbf854ab | 957 | if (cell->bit_offset || cell->nbits) |
69aba794 SK |
958 | nvmem_shift_read_buffer_in_place(cell, buf); |
959 | ||
3b4a6877 VG |
960 | if (len) |
961 | *len = cell->bytes; | |
69aba794 SK |
962 | |
963 | return 0; | |
964 | } | |
965 | ||
966 | /** | |
967 | * nvmem_cell_read() - Read a given nvmem cell | |
968 | * | |
969 | * @cell: nvmem cell to be read. | |
3b4a6877 VG |
970 | * @len: pointer to length of cell which will be populated on successful read; |
971 | * can be NULL. | |
69aba794 | 972 | * |
b577fafc BN |
973 | * Return: ERR_PTR() on error or a valid pointer to a buffer on success. The |
974 | * buffer should be freed by the consumer with a kfree(). | |
69aba794 SK |
975 | */ |
976 | void *nvmem_cell_read(struct nvmem_cell *cell, size_t *len) | |
977 | { | |
978 | struct nvmem_device *nvmem = cell->nvmem; | |
979 | u8 *buf; | |
980 | int rc; | |
981 | ||
795ddd18 | 982 | if (!nvmem) |
69aba794 SK |
983 | return ERR_PTR(-EINVAL); |
984 | ||
985 | buf = kzalloc(cell->bytes, GFP_KERNEL); | |
986 | if (!buf) | |
987 | return ERR_PTR(-ENOMEM); | |
988 | ||
989 | rc = __nvmem_cell_read(nvmem, cell, buf, len); | |
287980e4 | 990 | if (rc) { |
69aba794 SK |
991 | kfree(buf); |
992 | return ERR_PTR(rc); | |
993 | } | |
994 | ||
995 | return buf; | |
996 | } | |
997 | EXPORT_SYMBOL_GPL(nvmem_cell_read); | |
998 | ||
f7c04f16 MY |
999 | static void *nvmem_cell_prepare_write_buffer(struct nvmem_cell *cell, |
1000 | u8 *_buf, int len) | |
69aba794 SK |
1001 | { |
1002 | struct nvmem_device *nvmem = cell->nvmem; | |
1003 | int i, rc, nbits, bit_offset = cell->bit_offset; | |
1004 | u8 v, *p, *buf, *b, pbyte, pbits; | |
1005 | ||
1006 | nbits = cell->nbits; | |
1007 | buf = kzalloc(cell->bytes, GFP_KERNEL); | |
1008 | if (!buf) | |
1009 | return ERR_PTR(-ENOMEM); | |
1010 | ||
1011 | memcpy(buf, _buf, len); | |
1012 | p = b = buf; | |
1013 | ||
1014 | if (bit_offset) { | |
1015 | pbyte = *b; | |
1016 | *b <<= bit_offset; | |
1017 | ||
1018 | /* setup the first byte with lsb bits from nvmem */ | |
795ddd18 | 1019 | rc = nvmem_reg_read(nvmem, cell->offset, &v, 1); |
50808bfc MM |
1020 | if (rc) |
1021 | goto err; | |
69aba794 SK |
1022 | *b++ |= GENMASK(bit_offset - 1, 0) & v; |
1023 | ||
1024 | /* setup rest of the byte if any */ | |
1025 | for (i = 1; i < cell->bytes; i++) { | |
1026 | /* Get last byte bits and shift them towards lsb */ | |
1027 | pbits = pbyte >> (BITS_PER_BYTE - 1 - bit_offset); | |
1028 | pbyte = *b; | |
1029 | p = b; | |
1030 | *b <<= bit_offset; | |
1031 | *b++ |= pbits; | |
1032 | } | |
1033 | } | |
1034 | ||
1035 | /* if it's not end on byte boundary */ | |
1036 | if ((nbits + bit_offset) % BITS_PER_BYTE) { | |
1037 | /* setup the last byte with msb bits from nvmem */ | |
795ddd18 | 1038 | rc = nvmem_reg_read(nvmem, |
69aba794 | 1039 | cell->offset + cell->bytes - 1, &v, 1); |
50808bfc MM |
1040 | if (rc) |
1041 | goto err; | |
69aba794 SK |
1042 | *p |= GENMASK(7, (nbits + bit_offset) % BITS_PER_BYTE) & v; |
1043 | ||
1044 | } | |
1045 | ||
1046 | return buf; | |
50808bfc MM |
1047 | err: |
1048 | kfree(buf); | |
1049 | return ERR_PTR(rc); | |
69aba794 SK |
1050 | } |
1051 | ||
1052 | /** | |
1053 | * nvmem_cell_write() - Write to a given nvmem cell | |
1054 | * | |
1055 | * @cell: nvmem cell to be written. | |
1056 | * @buf: Buffer to be written. | |
1057 | * @len: length of buffer to be written to nvmem cell. | |
1058 | * | |
1059 | * Return: length of bytes written or negative on failure. | |
1060 | */ | |
1061 | int nvmem_cell_write(struct nvmem_cell *cell, void *buf, size_t len) | |
1062 | { | |
1063 | struct nvmem_device *nvmem = cell->nvmem; | |
1064 | int rc; | |
1065 | ||
795ddd18 | 1066 | if (!nvmem || nvmem->read_only || |
69aba794 SK |
1067 | (cell->bit_offset == 0 && len != cell->bytes)) |
1068 | return -EINVAL; | |
1069 | ||
1070 | if (cell->bit_offset || cell->nbits) { | |
1071 | buf = nvmem_cell_prepare_write_buffer(cell, buf, len); | |
1072 | if (IS_ERR(buf)) | |
1073 | return PTR_ERR(buf); | |
1074 | } | |
1075 | ||
795ddd18 | 1076 | rc = nvmem_reg_write(nvmem, cell->offset, buf, cell->bytes); |
69aba794 SK |
1077 | |
1078 | /* free the tmp buffer */ | |
ace22170 | 1079 | if (cell->bit_offset || cell->nbits) |
69aba794 SK |
1080 | kfree(buf); |
1081 | ||
287980e4 | 1082 | if (rc) |
69aba794 SK |
1083 | return rc; |
1084 | ||
1085 | return len; | |
1086 | } | |
1087 | EXPORT_SYMBOL_GPL(nvmem_cell_write); | |
1088 | ||
0a9b2d1c FG |
1089 | /** |
1090 | * nvmem_cell_read_u16() - Read a cell value as an u16 | |
1091 | * | |
1092 | * @dev: Device that requests the nvmem cell. | |
1093 | * @cell_id: Name of nvmem cell to read. | |
1094 | * @val: pointer to output value. | |
1095 | * | |
1096 | * Return: 0 on success or negative errno. | |
1097 | */ | |
1098 | int nvmem_cell_read_u16(struct device *dev, const char *cell_id, u16 *val) | |
1099 | { | |
1100 | struct nvmem_cell *cell; | |
1101 | void *buf; | |
1102 | size_t len; | |
1103 | ||
1104 | cell = nvmem_cell_get(dev, cell_id); | |
1105 | if (IS_ERR(cell)) | |
1106 | return PTR_ERR(cell); | |
1107 | ||
1108 | buf = nvmem_cell_read(cell, &len); | |
1109 | if (IS_ERR(buf)) { | |
1110 | nvmem_cell_put(cell); | |
1111 | return PTR_ERR(buf); | |
1112 | } | |
1113 | if (len != sizeof(*val)) { | |
1114 | kfree(buf); | |
1115 | nvmem_cell_put(cell); | |
1116 | return -EINVAL; | |
1117 | } | |
1118 | memcpy(val, buf, sizeof(*val)); | |
1119 | kfree(buf); | |
1120 | nvmem_cell_put(cell); | |
1121 | ||
1122 | return 0; | |
1123 | } | |
1124 | EXPORT_SYMBOL_GPL(nvmem_cell_read_u16); | |
1125 | ||
d026d70a LC |
1126 | /** |
1127 | * nvmem_cell_read_u32() - Read a cell value as an u32 | |
1128 | * | |
1129 | * @dev: Device that requests the nvmem cell. | |
1130 | * @cell_id: Name of nvmem cell to read. | |
1131 | * @val: pointer to output value. | |
1132 | * | |
1133 | * Return: 0 on success or negative errno. | |
1134 | */ | |
1135 | int nvmem_cell_read_u32(struct device *dev, const char *cell_id, u32 *val) | |
1136 | { | |
1137 | struct nvmem_cell *cell; | |
1138 | void *buf; | |
1139 | size_t len; | |
1140 | ||
1141 | cell = nvmem_cell_get(dev, cell_id); | |
1142 | if (IS_ERR(cell)) | |
1143 | return PTR_ERR(cell); | |
1144 | ||
1145 | buf = nvmem_cell_read(cell, &len); | |
1146 | if (IS_ERR(buf)) { | |
1147 | nvmem_cell_put(cell); | |
1148 | return PTR_ERR(buf); | |
1149 | } | |
1150 | if (len != sizeof(*val)) { | |
1151 | kfree(buf); | |
1152 | nvmem_cell_put(cell); | |
1153 | return -EINVAL; | |
1154 | } | |
1155 | memcpy(val, buf, sizeof(*val)); | |
1156 | ||
1157 | kfree(buf); | |
1158 | nvmem_cell_put(cell); | |
1159 | return 0; | |
1160 | } | |
1161 | EXPORT_SYMBOL_GPL(nvmem_cell_read_u32); | |
1162 | ||
e2a5402e SK |
1163 | /** |
1164 | * nvmem_device_cell_read() - Read a given nvmem device and cell | |
1165 | * | |
1166 | * @nvmem: nvmem device to read from. | |
1167 | * @info: nvmem cell info to be read. | |
1168 | * @buf: buffer pointer which will be populated on successful read. | |
1169 | * | |
1170 | * Return: length of successful bytes read on success and negative | |
1171 | * error code on error. | |
1172 | */ | |
1173 | ssize_t nvmem_device_cell_read(struct nvmem_device *nvmem, | |
1174 | struct nvmem_cell_info *info, void *buf) | |
1175 | { | |
1176 | struct nvmem_cell cell; | |
1177 | int rc; | |
1178 | ssize_t len; | |
1179 | ||
795ddd18 | 1180 | if (!nvmem) |
e2a5402e SK |
1181 | return -EINVAL; |
1182 | ||
1183 | rc = nvmem_cell_info_to_nvmem_cell(nvmem, info, &cell); | |
287980e4 | 1184 | if (rc) |
e2a5402e SK |
1185 | return rc; |
1186 | ||
1187 | rc = __nvmem_cell_read(nvmem, &cell, buf, &len); | |
287980e4 | 1188 | if (rc) |
e2a5402e SK |
1189 | return rc; |
1190 | ||
1191 | return len; | |
1192 | } | |
1193 | EXPORT_SYMBOL_GPL(nvmem_device_cell_read); | |
1194 | ||
1195 | /** | |
1196 | * nvmem_device_cell_write() - Write cell to a given nvmem device | |
1197 | * | |
1198 | * @nvmem: nvmem device to be written to. | |
29143268 | 1199 | * @info: nvmem cell info to be written. |
e2a5402e SK |
1200 | * @buf: buffer to be written to cell. |
1201 | * | |
1202 | * Return: length of bytes written or negative error code on failure. | |
48f63a2c | 1203 | */ |
e2a5402e SK |
1204 | int nvmem_device_cell_write(struct nvmem_device *nvmem, |
1205 | struct nvmem_cell_info *info, void *buf) | |
1206 | { | |
1207 | struct nvmem_cell cell; | |
1208 | int rc; | |
1209 | ||
795ddd18 | 1210 | if (!nvmem) |
e2a5402e SK |
1211 | return -EINVAL; |
1212 | ||
1213 | rc = nvmem_cell_info_to_nvmem_cell(nvmem, info, &cell); | |
287980e4 | 1214 | if (rc) |
e2a5402e SK |
1215 | return rc; |
1216 | ||
1217 | return nvmem_cell_write(&cell, buf, cell.bytes); | |
1218 | } | |
1219 | EXPORT_SYMBOL_GPL(nvmem_device_cell_write); | |
1220 | ||
1221 | /** | |
1222 | * nvmem_device_read() - Read from a given nvmem device | |
1223 | * | |
1224 | * @nvmem: nvmem device to read from. | |
1225 | * @offset: offset in nvmem device. | |
1226 | * @bytes: number of bytes to read. | |
1227 | * @buf: buffer pointer which will be populated on successful read. | |
1228 | * | |
1229 | * Return: length of successful bytes read on success and negative | |
1230 | * error code on error. | |
1231 | */ | |
1232 | int nvmem_device_read(struct nvmem_device *nvmem, | |
1233 | unsigned int offset, | |
1234 | size_t bytes, void *buf) | |
1235 | { | |
1236 | int rc; | |
1237 | ||
795ddd18 | 1238 | if (!nvmem) |
e2a5402e SK |
1239 | return -EINVAL; |
1240 | ||
795ddd18 | 1241 | rc = nvmem_reg_read(nvmem, offset, buf, bytes); |
e2a5402e | 1242 | |
287980e4 | 1243 | if (rc) |
e2a5402e SK |
1244 | return rc; |
1245 | ||
1246 | return bytes; | |
1247 | } | |
1248 | EXPORT_SYMBOL_GPL(nvmem_device_read); | |
1249 | ||
1250 | /** | |
1251 | * nvmem_device_write() - Write cell to a given nvmem device | |
1252 | * | |
1253 | * @nvmem: nvmem device to be written to. | |
1254 | * @offset: offset in nvmem device. | |
1255 | * @bytes: number of bytes to write. | |
1256 | * @buf: buffer to be written. | |
1257 | * | |
1258 | * Return: length of bytes written or negative error code on failure. | |
48f63a2c | 1259 | */ |
e2a5402e SK |
1260 | int nvmem_device_write(struct nvmem_device *nvmem, |
1261 | unsigned int offset, | |
1262 | size_t bytes, void *buf) | |
1263 | { | |
1264 | int rc; | |
1265 | ||
795ddd18 | 1266 | if (!nvmem) |
e2a5402e SK |
1267 | return -EINVAL; |
1268 | ||
795ddd18 | 1269 | rc = nvmem_reg_write(nvmem, offset, buf, bytes); |
e2a5402e | 1270 | |
287980e4 | 1271 | if (rc) |
e2a5402e SK |
1272 | return rc; |
1273 | ||
1274 | ||
1275 | return bytes; | |
1276 | } | |
1277 | EXPORT_SYMBOL_GPL(nvmem_device_write); | |
1278 | ||
b985f4cb BG |
1279 | /** |
1280 | * nvmem_add_cell_table() - register a table of cell info entries | |
1281 | * | |
1282 | * @table: table of cell info entries | |
1283 | */ | |
1284 | void nvmem_add_cell_table(struct nvmem_cell_table *table) | |
1285 | { | |
1286 | mutex_lock(&nvmem_cell_mutex); | |
1287 | list_add_tail(&table->node, &nvmem_cell_tables); | |
1288 | mutex_unlock(&nvmem_cell_mutex); | |
1289 | } | |
1290 | EXPORT_SYMBOL_GPL(nvmem_add_cell_table); | |
1291 | ||
1292 | /** | |
1293 | * nvmem_del_cell_table() - remove a previously registered cell info table | |
1294 | * | |
1295 | * @table: table of cell info entries | |
1296 | */ | |
1297 | void nvmem_del_cell_table(struct nvmem_cell_table *table) | |
1298 | { | |
1299 | mutex_lock(&nvmem_cell_mutex); | |
1300 | list_del(&table->node); | |
1301 | mutex_unlock(&nvmem_cell_mutex); | |
1302 | } | |
1303 | EXPORT_SYMBOL_GPL(nvmem_del_cell_table); | |
1304 | ||
506157be BG |
1305 | /** |
1306 | * nvmem_add_cell_lookups() - register a list of cell lookup entries | |
1307 | * | |
1308 | * @entries: array of cell lookup entries | |
1309 | * @nentries: number of cell lookup entries in the array | |
1310 | */ | |
1311 | void nvmem_add_cell_lookups(struct nvmem_cell_lookup *entries, size_t nentries) | |
1312 | { | |
1313 | int i; | |
1314 | ||
1315 | mutex_lock(&nvmem_lookup_mutex); | |
1316 | for (i = 0; i < nentries; i++) | |
1317 | list_add_tail(&entries[i].node, &nvmem_lookup_list); | |
1318 | mutex_unlock(&nvmem_lookup_mutex); | |
1319 | } | |
1320 | EXPORT_SYMBOL_GPL(nvmem_add_cell_lookups); | |
1321 | ||
1322 | /** | |
1323 | * nvmem_del_cell_lookups() - remove a list of previously added cell lookup | |
1324 | * entries | |
1325 | * | |
1326 | * @entries: array of cell lookup entries | |
1327 | * @nentries: number of cell lookup entries in the array | |
1328 | */ | |
1329 | void nvmem_del_cell_lookups(struct nvmem_cell_lookup *entries, size_t nentries) | |
1330 | { | |
1331 | int i; | |
1332 | ||
1333 | mutex_lock(&nvmem_lookup_mutex); | |
1334 | for (i = 0; i < nentries; i++) | |
1335 | list_del(&entries[i].node); | |
1336 | mutex_unlock(&nvmem_lookup_mutex); | |
1337 | } | |
1338 | EXPORT_SYMBOL_GPL(nvmem_del_cell_lookups); | |
1339 | ||
d7b9fd16 BG |
1340 | /** |
1341 | * nvmem_dev_name() - Get the name of a given nvmem device. | |
1342 | * | |
1343 | * @nvmem: nvmem device. | |
1344 | * | |
1345 | * Return: name of the nvmem device. | |
1346 | */ | |
1347 | const char *nvmem_dev_name(struct nvmem_device *nvmem) | |
1348 | { | |
1349 | return dev_name(&nvmem->dev); | |
1350 | } | |
1351 | EXPORT_SYMBOL_GPL(nvmem_dev_name); | |
1352 | ||
eace75cf SK |
1353 | static int __init nvmem_init(void) |
1354 | { | |
1355 | return bus_register(&nvmem_bus_type); | |
1356 | } | |
1357 | ||
1358 | static void __exit nvmem_exit(void) | |
1359 | { | |
1360 | bus_unregister(&nvmem_bus_type); | |
1361 | } | |
1362 | ||
1363 | subsys_initcall(nvmem_init); | |
1364 | module_exit(nvmem_exit); | |
1365 | ||
1366 | MODULE_AUTHOR("Srinivas Kandagatla <srinivas.kandagatla@linaro.org"); | |
1367 | MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com"); | |
1368 | MODULE_DESCRIPTION("nvmem Driver Core"); | |
1369 | MODULE_LICENSE("GPL v2"); |