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b83a313b MB |
1 | /* |
2 | * Register map access API | |
3 | * | |
4 | * Copyright 2011 Wolfson Microelectronics plc | |
5 | * | |
6 | * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License version 2 as | |
10 | * published by the Free Software Foundation. | |
11 | */ | |
12 | ||
13 | #include <linux/slab.h> | |
14 | #include <linux/module.h> | |
15 | #include <linux/mutex.h> | |
16 | #include <linux/err.h> | |
17 | ||
fb2736bb MB |
18 | #define CREATE_TRACE_POINTS |
19 | #include <trace/events/regmap.h> | |
20 | ||
93de9124 | 21 | #include "internal.h" |
b83a313b MB |
22 | |
23 | static void regmap_format_4_12_write(struct regmap *map, | |
24 | unsigned int reg, unsigned int val) | |
25 | { | |
26 | __be16 *out = map->work_buf; | |
27 | *out = cpu_to_be16((reg << 12) | val); | |
28 | } | |
29 | ||
30 | static void regmap_format_7_9_write(struct regmap *map, | |
31 | unsigned int reg, unsigned int val) | |
32 | { | |
33 | __be16 *out = map->work_buf; | |
34 | *out = cpu_to_be16((reg << 9) | val); | |
35 | } | |
36 | ||
37 | static void regmap_format_8(void *buf, unsigned int val) | |
38 | { | |
39 | u8 *b = buf; | |
40 | ||
41 | b[0] = val; | |
42 | } | |
43 | ||
44 | static void regmap_format_16(void *buf, unsigned int val) | |
45 | { | |
46 | __be16 *b = buf; | |
47 | ||
48 | b[0] = cpu_to_be16(val); | |
49 | } | |
50 | ||
51 | static unsigned int regmap_parse_8(void *buf) | |
52 | { | |
53 | u8 *b = buf; | |
54 | ||
55 | return b[0]; | |
56 | } | |
57 | ||
58 | static unsigned int regmap_parse_16(void *buf) | |
59 | { | |
60 | __be16 *b = buf; | |
61 | ||
62 | b[0] = be16_to_cpu(b[0]); | |
63 | ||
64 | return b[0]; | |
65 | } | |
66 | ||
67 | /** | |
68 | * regmap_init(): Initialise register map | |
69 | * | |
70 | * @dev: Device that will be interacted with | |
71 | * @bus: Bus-specific callbacks to use with device | |
72 | * @config: Configuration for register map | |
73 | * | |
74 | * The return value will be an ERR_PTR() on error or a valid pointer to | |
75 | * a struct regmap. This function should generally not be called | |
76 | * directly, it should be called by bus-specific init functions. | |
77 | */ | |
78 | struct regmap *regmap_init(struct device *dev, | |
79 | const struct regmap_bus *bus, | |
80 | const struct regmap_config *config) | |
81 | { | |
82 | struct regmap *map; | |
83 | int ret = -EINVAL; | |
84 | ||
85 | if (!bus || !config) | |
86 | return NULL; | |
87 | ||
88 | map = kzalloc(sizeof(*map), GFP_KERNEL); | |
89 | if (map == NULL) { | |
90 | ret = -ENOMEM; | |
91 | goto err; | |
92 | } | |
93 | ||
94 | mutex_init(&map->lock); | |
95 | map->format.buf_size = (config->reg_bits + config->val_bits) / 8; | |
96 | map->format.reg_bytes = config->reg_bits / 8; | |
97 | map->format.val_bytes = config->val_bits / 8; | |
98 | map->dev = dev; | |
99 | map->bus = bus; | |
2e2ae66d MB |
100 | map->max_register = config->max_register; |
101 | map->writeable_reg = config->writeable_reg; | |
102 | map->readable_reg = config->readable_reg; | |
103 | map->volatile_reg = config->volatile_reg; | |
2efe1642 | 104 | map->precious_reg = config->precious_reg; |
b83a313b MB |
105 | |
106 | switch (config->reg_bits) { | |
107 | case 4: | |
108 | switch (config->val_bits) { | |
109 | case 12: | |
110 | map->format.format_write = regmap_format_4_12_write; | |
111 | break; | |
112 | default: | |
113 | goto err_map; | |
114 | } | |
115 | break; | |
116 | ||
117 | case 7: | |
118 | switch (config->val_bits) { | |
119 | case 9: | |
120 | map->format.format_write = regmap_format_7_9_write; | |
121 | break; | |
122 | default: | |
123 | goto err_map; | |
124 | } | |
125 | break; | |
126 | ||
127 | case 8: | |
128 | map->format.format_reg = regmap_format_8; | |
129 | break; | |
130 | ||
131 | case 16: | |
132 | map->format.format_reg = regmap_format_16; | |
133 | break; | |
134 | ||
135 | default: | |
136 | goto err_map; | |
137 | } | |
138 | ||
139 | switch (config->val_bits) { | |
140 | case 8: | |
141 | map->format.format_val = regmap_format_8; | |
142 | map->format.parse_val = regmap_parse_8; | |
143 | break; | |
144 | case 16: | |
145 | map->format.format_val = regmap_format_16; | |
146 | map->format.parse_val = regmap_parse_16; | |
147 | break; | |
148 | } | |
149 | ||
150 | if (!map->format.format_write && | |
151 | !(map->format.format_reg && map->format.format_val)) | |
152 | goto err_map; | |
153 | ||
154 | map->work_buf = kmalloc(map->format.buf_size, GFP_KERNEL); | |
155 | if (map->work_buf == NULL) { | |
156 | ret = -ENOMEM; | |
157 | goto err_bus; | |
158 | } | |
159 | ||
31244e39 MB |
160 | regmap_debugfs_init(map); |
161 | ||
b83a313b MB |
162 | return map; |
163 | ||
164 | err_bus: | |
165 | module_put(map->bus->owner); | |
166 | err_map: | |
167 | kfree(map); | |
168 | err: | |
169 | return ERR_PTR(ret); | |
170 | } | |
171 | EXPORT_SYMBOL_GPL(regmap_init); | |
172 | ||
173 | /** | |
174 | * regmap_exit(): Free a previously allocated register map | |
175 | */ | |
176 | void regmap_exit(struct regmap *map) | |
177 | { | |
31244e39 | 178 | regmap_debugfs_exit(map); |
b83a313b MB |
179 | kfree(map->work_buf); |
180 | module_put(map->bus->owner); | |
181 | kfree(map); | |
182 | } | |
183 | EXPORT_SYMBOL_GPL(regmap_exit); | |
184 | ||
185 | static int _regmap_raw_write(struct regmap *map, unsigned int reg, | |
186 | const void *val, size_t val_len) | |
187 | { | |
188 | void *buf; | |
189 | int ret = -ENOTSUPP; | |
190 | size_t len; | |
73304781 MB |
191 | int i; |
192 | ||
193 | /* Check for unwritable registers before we start */ | |
194 | if (map->writeable_reg) | |
195 | for (i = 0; i < val_len / map->format.val_bytes; i++) | |
196 | if (!map->writeable_reg(map->dev, reg + i)) | |
197 | return -EINVAL; | |
b83a313b MB |
198 | |
199 | map->format.format_reg(map->work_buf, reg); | |
200 | ||
fb2736bb MB |
201 | trace_regmap_hw_write_start(map->dev, reg, |
202 | val_len / map->format.val_bytes); | |
203 | ||
2547e201 MB |
204 | /* If we're doing a single register write we can probably just |
205 | * send the work_buf directly, otherwise try to do a gather | |
206 | * write. | |
207 | */ | |
208 | if (val == map->work_buf + map->format.reg_bytes) | |
209 | ret = map->bus->write(map->dev, map->work_buf, | |
210 | map->format.reg_bytes + val_len); | |
211 | else if (map->bus->gather_write) | |
b83a313b MB |
212 | ret = map->bus->gather_write(map->dev, map->work_buf, |
213 | map->format.reg_bytes, | |
214 | val, val_len); | |
215 | ||
2547e201 | 216 | /* If that didn't work fall back on linearising by hand. */ |
b83a313b MB |
217 | if (ret == -ENOTSUPP) { |
218 | len = map->format.reg_bytes + val_len; | |
219 | buf = kmalloc(len, GFP_KERNEL); | |
220 | if (!buf) | |
221 | return -ENOMEM; | |
222 | ||
223 | memcpy(buf, map->work_buf, map->format.reg_bytes); | |
224 | memcpy(buf + map->format.reg_bytes, val, val_len); | |
225 | ret = map->bus->write(map->dev, buf, len); | |
226 | ||
227 | kfree(buf); | |
228 | } | |
229 | ||
fb2736bb MB |
230 | trace_regmap_hw_write_done(map->dev, reg, |
231 | val_len / map->format.val_bytes); | |
232 | ||
b83a313b MB |
233 | return ret; |
234 | } | |
235 | ||
236 | static int _regmap_write(struct regmap *map, unsigned int reg, | |
237 | unsigned int val) | |
238 | { | |
fb2736bb | 239 | int ret; |
b83a313b MB |
240 | BUG_ON(!map->format.format_write && !map->format.format_val); |
241 | ||
fb2736bb MB |
242 | trace_regmap_reg_write(map->dev, reg, val); |
243 | ||
b83a313b MB |
244 | if (map->format.format_write) { |
245 | map->format.format_write(map, reg, val); | |
246 | ||
fb2736bb MB |
247 | trace_regmap_hw_write_start(map->dev, reg, 1); |
248 | ||
249 | ret = map->bus->write(map->dev, map->work_buf, | |
250 | map->format.buf_size); | |
251 | ||
252 | trace_regmap_hw_write_done(map->dev, reg, 1); | |
253 | ||
254 | return ret; | |
b83a313b MB |
255 | } else { |
256 | map->format.format_val(map->work_buf + map->format.reg_bytes, | |
257 | val); | |
258 | return _regmap_raw_write(map, reg, | |
259 | map->work_buf + map->format.reg_bytes, | |
260 | map->format.val_bytes); | |
261 | } | |
262 | } | |
263 | ||
264 | /** | |
265 | * regmap_write(): Write a value to a single register | |
266 | * | |
267 | * @map: Register map to write to | |
268 | * @reg: Register to write to | |
269 | * @val: Value to be written | |
270 | * | |
271 | * A value of zero will be returned on success, a negative errno will | |
272 | * be returned in error cases. | |
273 | */ | |
274 | int regmap_write(struct regmap *map, unsigned int reg, unsigned int val) | |
275 | { | |
276 | int ret; | |
277 | ||
278 | mutex_lock(&map->lock); | |
279 | ||
280 | ret = _regmap_write(map, reg, val); | |
281 | ||
282 | mutex_unlock(&map->lock); | |
283 | ||
284 | return ret; | |
285 | } | |
286 | EXPORT_SYMBOL_GPL(regmap_write); | |
287 | ||
288 | /** | |
289 | * regmap_raw_write(): Write raw values to one or more registers | |
290 | * | |
291 | * @map: Register map to write to | |
292 | * @reg: Initial register to write to | |
293 | * @val: Block of data to be written, laid out for direct transmission to the | |
294 | * device | |
295 | * @val_len: Length of data pointed to by val. | |
296 | * | |
297 | * This function is intended to be used for things like firmware | |
298 | * download where a large block of data needs to be transferred to the | |
299 | * device. No formatting will be done on the data provided. | |
300 | * | |
301 | * A value of zero will be returned on success, a negative errno will | |
302 | * be returned in error cases. | |
303 | */ | |
304 | int regmap_raw_write(struct regmap *map, unsigned int reg, | |
305 | const void *val, size_t val_len) | |
306 | { | |
307 | int ret; | |
308 | ||
309 | mutex_lock(&map->lock); | |
310 | ||
311 | ret = _regmap_raw_write(map, reg, val, val_len); | |
312 | ||
313 | mutex_unlock(&map->lock); | |
314 | ||
315 | return ret; | |
316 | } | |
317 | EXPORT_SYMBOL_GPL(regmap_raw_write); | |
318 | ||
319 | static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val, | |
320 | unsigned int val_len) | |
321 | { | |
322 | u8 *u8 = map->work_buf; | |
323 | int ret; | |
324 | ||
325 | map->format.format_reg(map->work_buf, reg); | |
326 | ||
327 | /* | |
328 | * Some buses flag reads by setting the high bits in the | |
329 | * register addresss; since it's always the high bits for all | |
330 | * current formats we can do this here rather than in | |
331 | * formatting. This may break if we get interesting formats. | |
332 | */ | |
333 | if (map->bus->read_flag_mask) | |
334 | u8[0] |= map->bus->read_flag_mask; | |
335 | ||
fb2736bb MB |
336 | trace_regmap_hw_read_start(map->dev, reg, |
337 | val_len / map->format.val_bytes); | |
338 | ||
b83a313b | 339 | ret = map->bus->read(map->dev, map->work_buf, map->format.reg_bytes, |
40c5cc26 | 340 | val, val_len); |
b83a313b | 341 | |
fb2736bb MB |
342 | trace_regmap_hw_read_done(map->dev, reg, |
343 | val_len / map->format.val_bytes); | |
344 | ||
345 | return ret; | |
b83a313b MB |
346 | } |
347 | ||
348 | static int _regmap_read(struct regmap *map, unsigned int reg, | |
349 | unsigned int *val) | |
350 | { | |
351 | int ret; | |
352 | ||
353 | if (!map->format.parse_val) | |
354 | return -EINVAL; | |
355 | ||
356 | ret = _regmap_raw_read(map, reg, map->work_buf, map->format.val_bytes); | |
fb2736bb | 357 | if (ret == 0) { |
b83a313b | 358 | *val = map->format.parse_val(map->work_buf); |
fb2736bb MB |
359 | trace_regmap_reg_read(map->dev, reg, *val); |
360 | } | |
b83a313b MB |
361 | |
362 | return ret; | |
363 | } | |
364 | ||
365 | /** | |
366 | * regmap_read(): Read a value from a single register | |
367 | * | |
368 | * @map: Register map to write to | |
369 | * @reg: Register to be read from | |
370 | * @val: Pointer to store read value | |
371 | * | |
372 | * A value of zero will be returned on success, a negative errno will | |
373 | * be returned in error cases. | |
374 | */ | |
375 | int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val) | |
376 | { | |
377 | int ret; | |
378 | ||
379 | mutex_lock(&map->lock); | |
380 | ||
381 | ret = _regmap_read(map, reg, val); | |
382 | ||
383 | mutex_unlock(&map->lock); | |
384 | ||
385 | return ret; | |
386 | } | |
387 | EXPORT_SYMBOL_GPL(regmap_read); | |
388 | ||
389 | /** | |
390 | * regmap_raw_read(): Read raw data from the device | |
391 | * | |
392 | * @map: Register map to write to | |
393 | * @reg: First register to be read from | |
394 | * @val: Pointer to store read value | |
395 | * @val_len: Size of data to read | |
396 | * | |
397 | * A value of zero will be returned on success, a negative errno will | |
398 | * be returned in error cases. | |
399 | */ | |
400 | int regmap_raw_read(struct regmap *map, unsigned int reg, void *val, | |
401 | size_t val_len) | |
402 | { | |
403 | int ret; | |
404 | ||
405 | mutex_lock(&map->lock); | |
406 | ||
407 | ret = _regmap_raw_read(map, reg, val, val_len); | |
408 | ||
409 | mutex_unlock(&map->lock); | |
410 | ||
411 | return ret; | |
412 | } | |
413 | EXPORT_SYMBOL_GPL(regmap_raw_read); | |
414 | ||
415 | /** | |
416 | * regmap_bulk_read(): Read multiple registers from the device | |
417 | * | |
418 | * @map: Register map to write to | |
419 | * @reg: First register to be read from | |
420 | * @val: Pointer to store read value, in native register size for device | |
421 | * @val_count: Number of registers to read | |
422 | * | |
423 | * A value of zero will be returned on success, a negative errno will | |
424 | * be returned in error cases. | |
425 | */ | |
426 | int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val, | |
427 | size_t val_count) | |
428 | { | |
429 | int ret, i; | |
430 | size_t val_bytes = map->format.val_bytes; | |
431 | ||
432 | if (!map->format.parse_val) | |
433 | return -EINVAL; | |
434 | ||
435 | ret = regmap_raw_read(map, reg, val, val_bytes * val_count); | |
436 | if (ret != 0) | |
437 | return ret; | |
438 | ||
439 | for (i = 0; i < val_count * val_bytes; i += val_bytes) | |
440 | map->format.parse_val(val + i); | |
441 | ||
442 | return 0; | |
443 | } | |
444 | EXPORT_SYMBOL_GPL(regmap_bulk_read); | |
445 | ||
446 | /** | |
447 | * remap_update_bits: Perform a read/modify/write cycle on the register map | |
448 | * | |
449 | * @map: Register map to update | |
450 | * @reg: Register to update | |
451 | * @mask: Bitmask to change | |
452 | * @val: New value for bitmask | |
453 | * | |
454 | * Returns zero for success, a negative number on error. | |
455 | */ | |
456 | int regmap_update_bits(struct regmap *map, unsigned int reg, | |
457 | unsigned int mask, unsigned int val) | |
458 | { | |
459 | int ret; | |
460 | unsigned int tmp; | |
461 | ||
462 | mutex_lock(&map->lock); | |
463 | ||
464 | ret = _regmap_read(map, reg, &tmp); | |
465 | if (ret != 0) | |
466 | goto out; | |
467 | ||
468 | tmp &= ~mask; | |
469 | tmp |= val & mask; | |
470 | ||
471 | ret = _regmap_write(map, reg, tmp); | |
472 | ||
473 | out: | |
474 | mutex_unlock(&map->lock); | |
475 | ||
476 | return ret; | |
477 | } | |
478 | EXPORT_SYMBOL_GPL(regmap_update_bits); | |
31244e39 MB |
479 | |
480 | static int __init regmap_initcall(void) | |
481 | { | |
482 | regmap_debugfs_initcall(); | |
483 | ||
484 | return 0; | |
485 | } | |
486 | postcore_initcall(regmap_initcall); |