xref: /openbmc/linux/sound/hda/hdac_regmap.c (revision 3ce3e45c)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Regmap support for HD-audio verbs
4  *
5  * A virtual register is translated to one or more hda verbs for write,
6  * vice versa for read.
7  *
8  * A few limitations:
9  * - Provided for not all verbs but only subset standard non-volatile verbs.
10  * - For reading, only AC_VERB_GET_* variants can be used.
11  * - For writing, mapped to the *corresponding* AC_VERB_SET_* variants,
12  *   so can't handle asymmetric verbs for read and write
13  */
14 
15 #include <linux/slab.h>
16 #include <linux/device.h>
17 #include <linux/regmap.h>
18 #include <linux/export.h>
19 #include <linux/pm.h>
20 #include <linux/pm_runtime.h>
21 #include <sound/core.h>
22 #include <sound/hdaudio.h>
23 #include <sound/hda_regmap.h>
24 #include "local.h"
25 
26 static int codec_pm_lock(struct hdac_device *codec)
27 {
28 	return snd_hdac_keep_power_up(codec);
29 }
30 
31 static void codec_pm_unlock(struct hdac_device *codec, int lock)
32 {
33 	if (lock == 1)
34 		snd_hdac_power_down_pm(codec);
35 }
36 
37 #define get_verb(reg)	(((reg) >> 8) & 0xfff)
38 
39 static bool hda_volatile_reg(struct device *dev, unsigned int reg)
40 {
41 	struct hdac_device *codec = dev_to_hdac_dev(dev);
42 	unsigned int verb = get_verb(reg);
43 
44 	switch (verb) {
45 	case AC_VERB_GET_PROC_COEF:
46 		return !codec->cache_coef;
47 	case AC_VERB_GET_COEF_INDEX:
48 	case AC_VERB_GET_PROC_STATE:
49 	case AC_VERB_GET_POWER_STATE:
50 	case AC_VERB_GET_PIN_SENSE:
51 	case AC_VERB_GET_HDMI_DIP_SIZE:
52 	case AC_VERB_GET_HDMI_ELDD:
53 	case AC_VERB_GET_HDMI_DIP_INDEX:
54 	case AC_VERB_GET_HDMI_DIP_DATA:
55 	case AC_VERB_GET_HDMI_DIP_XMIT:
56 	case AC_VERB_GET_HDMI_CP_CTRL:
57 	case AC_VERB_GET_HDMI_CHAN_SLOT:
58 	case AC_VERB_GET_DEVICE_SEL:
59 	case AC_VERB_GET_DEVICE_LIST:	/* read-only volatile */
60 		return true;
61 	}
62 
63 	return false;
64 }
65 
66 static bool hda_writeable_reg(struct device *dev, unsigned int reg)
67 {
68 	struct hdac_device *codec = dev_to_hdac_dev(dev);
69 	unsigned int verb = get_verb(reg);
70 	const unsigned int *v;
71 	int i;
72 
73 	snd_array_for_each(&codec->vendor_verbs, i, v) {
74 		if (verb == *v)
75 			return true;
76 	}
77 
78 	if (codec->caps_overwriting)
79 		return true;
80 
81 	switch (verb & 0xf00) {
82 	case AC_VERB_GET_STREAM_FORMAT:
83 	case AC_VERB_GET_AMP_GAIN_MUTE:
84 		return true;
85 	case AC_VERB_GET_PROC_COEF:
86 		return codec->cache_coef;
87 	case 0xf00:
88 		break;
89 	default:
90 		return false;
91 	}
92 
93 	switch (verb) {
94 	case AC_VERB_GET_CONNECT_SEL:
95 	case AC_VERB_GET_SDI_SELECT:
96 	case AC_VERB_GET_PIN_WIDGET_CONTROL:
97 	case AC_VERB_GET_UNSOLICITED_RESPONSE: /* only as SET_UNSOLICITED_ENABLE */
98 	case AC_VERB_GET_BEEP_CONTROL:
99 	case AC_VERB_GET_EAPD_BTLENABLE:
100 	case AC_VERB_GET_DIGI_CONVERT_1:
101 	case AC_VERB_GET_DIGI_CONVERT_2: /* only for beep control */
102 	case AC_VERB_GET_VOLUME_KNOB_CONTROL:
103 	case AC_VERB_GET_GPIO_MASK:
104 	case AC_VERB_GET_GPIO_DIRECTION:
105 	case AC_VERB_GET_GPIO_DATA: /* not for volatile read */
106 	case AC_VERB_GET_GPIO_WAKE_MASK:
107 	case AC_VERB_GET_GPIO_UNSOLICITED_RSP_MASK:
108 	case AC_VERB_GET_GPIO_STICKY_MASK:
109 		return true;
110 	}
111 
112 	return false;
113 }
114 
115 static bool hda_readable_reg(struct device *dev, unsigned int reg)
116 {
117 	struct hdac_device *codec = dev_to_hdac_dev(dev);
118 	unsigned int verb = get_verb(reg);
119 
120 	if (codec->caps_overwriting)
121 		return true;
122 
123 	switch (verb) {
124 	case AC_VERB_PARAMETERS:
125 	case AC_VERB_GET_CONNECT_LIST:
126 	case AC_VERB_GET_SUBSYSTEM_ID:
127 		return true;
128 	/* below are basically writable, but disabled for reducing unnecessary
129 	 * writes at sync
130 	 */
131 	case AC_VERB_GET_CONFIG_DEFAULT: /* usually just read */
132 	case AC_VERB_GET_CONV: /* managed in PCM code */
133 	case AC_VERB_GET_CVT_CHAN_COUNT: /* managed in HDMI CA code */
134 		return true;
135 	}
136 
137 	return hda_writeable_reg(dev, reg);
138 }
139 
140 /*
141  * Stereo amp pseudo register:
142  * for making easier to handle the stereo volume control, we provide a
143  * fake register to deal both left and right channels by a single
144  * (pseudo) register access.  A verb consisting of SET_AMP_GAIN with
145  * *both* SET_LEFT and SET_RIGHT bits takes a 16bit value, the lower 8bit
146  * for the left and the upper 8bit for the right channel.
147  */
148 static bool is_stereo_amp_verb(unsigned int reg)
149 {
150 	if (((reg >> 8) & 0x700) != AC_VERB_SET_AMP_GAIN_MUTE)
151 		return false;
152 	return (reg & (AC_AMP_SET_LEFT | AC_AMP_SET_RIGHT)) ==
153 		(AC_AMP_SET_LEFT | AC_AMP_SET_RIGHT);
154 }
155 
156 /* read a pseudo stereo amp register (16bit left+right) */
157 static int hda_reg_read_stereo_amp(struct hdac_device *codec,
158 				   unsigned int reg, unsigned int *val)
159 {
160 	unsigned int left, right;
161 	int err;
162 
163 	reg &= ~(AC_AMP_SET_LEFT | AC_AMP_SET_RIGHT);
164 	err = snd_hdac_exec_verb(codec, reg | AC_AMP_GET_LEFT, 0, &left);
165 	if (err < 0)
166 		return err;
167 	err = snd_hdac_exec_verb(codec, reg | AC_AMP_GET_RIGHT, 0, &right);
168 	if (err < 0)
169 		return err;
170 	*val = left | (right << 8);
171 	return 0;
172 }
173 
174 /* write a pseudo stereo amp register (16bit left+right) */
175 static int hda_reg_write_stereo_amp(struct hdac_device *codec,
176 				    unsigned int reg, unsigned int val)
177 {
178 	int err;
179 	unsigned int verb, left, right;
180 
181 	verb = AC_VERB_SET_AMP_GAIN_MUTE << 8;
182 	if (reg & AC_AMP_GET_OUTPUT)
183 		verb |= AC_AMP_SET_OUTPUT;
184 	else
185 		verb |= AC_AMP_SET_INPUT | ((reg & 0xf) << 8);
186 	reg = (reg & ~0xfffff) | verb;
187 
188 	left = val & 0xff;
189 	right = (val >> 8) & 0xff;
190 	if (left == right) {
191 		reg |= AC_AMP_SET_LEFT | AC_AMP_SET_RIGHT;
192 		return snd_hdac_exec_verb(codec, reg | left, 0, NULL);
193 	}
194 
195 	err = snd_hdac_exec_verb(codec, reg | AC_AMP_SET_LEFT | left, 0, NULL);
196 	if (err < 0)
197 		return err;
198 	err = snd_hdac_exec_verb(codec, reg | AC_AMP_SET_RIGHT | right, 0, NULL);
199 	if (err < 0)
200 		return err;
201 	return 0;
202 }
203 
204 /* read a pseudo coef register (16bit) */
205 static int hda_reg_read_coef(struct hdac_device *codec, unsigned int reg,
206 			     unsigned int *val)
207 {
208 	unsigned int verb;
209 	int err;
210 
211 	if (!codec->cache_coef)
212 		return -EINVAL;
213 	/* LSB 8bit = coef index */
214 	verb = (reg & ~0xfff00) | (AC_VERB_SET_COEF_INDEX << 8);
215 	err = snd_hdac_exec_verb(codec, verb, 0, NULL);
216 	if (err < 0)
217 		return err;
218 	verb = (reg & ~0xfffff) | (AC_VERB_GET_COEF_INDEX << 8);
219 	return snd_hdac_exec_verb(codec, verb, 0, val);
220 }
221 
222 /* write a pseudo coef register (16bit) */
223 static int hda_reg_write_coef(struct hdac_device *codec, unsigned int reg,
224 			      unsigned int val)
225 {
226 	unsigned int verb;
227 	int err;
228 
229 	if (!codec->cache_coef)
230 		return -EINVAL;
231 	/* LSB 8bit = coef index */
232 	verb = (reg & ~0xfff00) | (AC_VERB_SET_COEF_INDEX << 8);
233 	err = snd_hdac_exec_verb(codec, verb, 0, NULL);
234 	if (err < 0)
235 		return err;
236 	verb = (reg & ~0xfffff) | (AC_VERB_GET_COEF_INDEX << 8) |
237 		(val & 0xffff);
238 	return snd_hdac_exec_verb(codec, verb, 0, NULL);
239 }
240 
241 static int hda_reg_read(void *context, unsigned int reg, unsigned int *val)
242 {
243 	struct hdac_device *codec = context;
244 	int verb = get_verb(reg);
245 	int err;
246 	int pm_lock = 0;
247 
248 	if (verb != AC_VERB_GET_POWER_STATE) {
249 		pm_lock = codec_pm_lock(codec);
250 		if (pm_lock < 0)
251 			return -EAGAIN;
252 	}
253 	reg |= (codec->addr << 28);
254 	if (is_stereo_amp_verb(reg)) {
255 		err = hda_reg_read_stereo_amp(codec, reg, val);
256 		goto out;
257 	}
258 	if (verb == AC_VERB_GET_PROC_COEF) {
259 		err = hda_reg_read_coef(codec, reg, val);
260 		goto out;
261 	}
262 	if ((verb & 0x700) == AC_VERB_SET_AMP_GAIN_MUTE)
263 		reg &= ~AC_AMP_FAKE_MUTE;
264 
265 	err = snd_hdac_exec_verb(codec, reg, 0, val);
266 	if (err < 0)
267 		goto out;
268 	/* special handling for asymmetric reads */
269 	if (verb == AC_VERB_GET_POWER_STATE) {
270 		if (*val & AC_PWRST_ERROR)
271 			*val = -1;
272 		else /* take only the actual state */
273 			*val = (*val >> 4) & 0x0f;
274 	}
275  out:
276 	codec_pm_unlock(codec, pm_lock);
277 	return err;
278 }
279 
280 static int hda_reg_write(void *context, unsigned int reg, unsigned int val)
281 {
282 	struct hdac_device *codec = context;
283 	unsigned int verb;
284 	int i, bytes, err;
285 	int pm_lock = 0;
286 
287 	if (codec->caps_overwriting)
288 		return 0;
289 
290 	reg &= ~0x00080000U; /* drop GET bit */
291 	reg |= (codec->addr << 28);
292 	verb = get_verb(reg);
293 
294 	if (verb != AC_VERB_SET_POWER_STATE) {
295 		pm_lock = codec_pm_lock(codec);
296 		if (pm_lock < 0)
297 			return codec->lazy_cache ? 0 : -EAGAIN;
298 	}
299 
300 	if (is_stereo_amp_verb(reg)) {
301 		err = hda_reg_write_stereo_amp(codec, reg, val);
302 		goto out;
303 	}
304 
305 	if (verb == AC_VERB_SET_PROC_COEF) {
306 		err = hda_reg_write_coef(codec, reg, val);
307 		goto out;
308 	}
309 
310 	switch (verb & 0xf00) {
311 	case AC_VERB_SET_AMP_GAIN_MUTE:
312 		if ((reg & AC_AMP_FAKE_MUTE) && (val & AC_AMP_MUTE))
313 			val = 0;
314 		verb = AC_VERB_SET_AMP_GAIN_MUTE;
315 		if (reg & AC_AMP_GET_LEFT)
316 			verb |= AC_AMP_SET_LEFT >> 8;
317 		else
318 			verb |= AC_AMP_SET_RIGHT >> 8;
319 		if (reg & AC_AMP_GET_OUTPUT) {
320 			verb |= AC_AMP_SET_OUTPUT >> 8;
321 		} else {
322 			verb |= AC_AMP_SET_INPUT >> 8;
323 			verb |= reg & 0xf;
324 		}
325 		break;
326 	}
327 
328 	switch (verb) {
329 	case AC_VERB_SET_DIGI_CONVERT_1:
330 		bytes = 2;
331 		break;
332 	case AC_VERB_SET_CONFIG_DEFAULT_BYTES_0:
333 		bytes = 4;
334 		break;
335 	default:
336 		bytes = 1;
337 		break;
338 	}
339 
340 	for (i = 0; i < bytes; i++) {
341 		reg &= ~0xfffff;
342 		reg |= (verb + i) << 8 | ((val >> (8 * i)) & 0xff);
343 		err = snd_hdac_exec_verb(codec, reg, 0, NULL);
344 		if (err < 0)
345 			goto out;
346 	}
347 
348  out:
349 	codec_pm_unlock(codec, pm_lock);
350 	return err;
351 }
352 
353 static const struct regmap_config hda_regmap_cfg = {
354 	.name = "hdaudio",
355 	.reg_bits = 32,
356 	.val_bits = 32,
357 	.max_register = 0xfffffff,
358 	.writeable_reg = hda_writeable_reg,
359 	.readable_reg = hda_readable_reg,
360 	.volatile_reg = hda_volatile_reg,
361 	.cache_type = REGCACHE_RBTREE,
362 	.reg_read = hda_reg_read,
363 	.reg_write = hda_reg_write,
364 	.use_single_read = true,
365 	.use_single_write = true,
366 	.disable_locking = true,
367 };
368 
369 /**
370  * snd_hdac_regmap_init - Initialize regmap for HDA register accesses
371  * @codec: the codec object
372  *
373  * Returns zero for success or a negative error code.
374  */
375 int snd_hdac_regmap_init(struct hdac_device *codec)
376 {
377 	struct regmap *regmap;
378 
379 	regmap = regmap_init(&codec->dev, NULL, codec, &hda_regmap_cfg);
380 	if (IS_ERR(regmap))
381 		return PTR_ERR(regmap);
382 	codec->regmap = regmap;
383 	snd_array_init(&codec->vendor_verbs, sizeof(unsigned int), 8);
384 	return 0;
385 }
386 EXPORT_SYMBOL_GPL(snd_hdac_regmap_init);
387 
388 /**
389  * snd_hdac_regmap_exit - Release the regmap from HDA codec
390  * @codec: the codec object
391  */
392 void snd_hdac_regmap_exit(struct hdac_device *codec)
393 {
394 	if (codec->regmap) {
395 		regmap_exit(codec->regmap);
396 		codec->regmap = NULL;
397 		snd_array_free(&codec->vendor_verbs);
398 	}
399 }
400 EXPORT_SYMBOL_GPL(snd_hdac_regmap_exit);
401 
402 /**
403  * snd_hdac_regmap_add_vendor_verb - add a vendor-specific verb to regmap
404  * @codec: the codec object
405  * @verb: verb to allow accessing via regmap
406  *
407  * Returns zero for success or a negative error code.
408  */
409 int snd_hdac_regmap_add_vendor_verb(struct hdac_device *codec,
410 				    unsigned int verb)
411 {
412 	unsigned int *p = snd_array_new(&codec->vendor_verbs);
413 
414 	if (!p)
415 		return -ENOMEM;
416 	*p = verb | 0x800; /* set GET bit */
417 	return 0;
418 }
419 EXPORT_SYMBOL_GPL(snd_hdac_regmap_add_vendor_verb);
420 
421 /*
422  * helper functions
423  */
424 
425 /* write a pseudo-register value (w/o power sequence) */
426 static int reg_raw_write(struct hdac_device *codec, unsigned int reg,
427 			 unsigned int val)
428 {
429 	int err;
430 
431 	mutex_lock(&codec->regmap_lock);
432 	if (!codec->regmap)
433 		err = hda_reg_write(codec, reg, val);
434 	else
435 		err = regmap_write(codec->regmap, reg, val);
436 	mutex_unlock(&codec->regmap_lock);
437 	return err;
438 }
439 
440 /* a helper macro to call @func_call; retry with power-up if failed */
441 #define CALL_RAW_FUNC(codec, func_call)				\
442 	({							\
443 		int _err = func_call;				\
444 		if (_err == -EAGAIN) {				\
445 			_err = snd_hdac_power_up_pm(codec);	\
446 			if (_err >= 0)				\
447 				_err = func_call;		\
448 			snd_hdac_power_down_pm(codec);		\
449 		}						\
450 		_err;})
451 
452 /**
453  * snd_hdac_regmap_write_raw - write a pseudo register with power mgmt
454  * @codec: the codec object
455  * @reg: pseudo register
456  * @val: value to write
457  *
458  * Returns zero if successful or a negative error code.
459  */
460 int snd_hdac_regmap_write_raw(struct hdac_device *codec, unsigned int reg,
461 			      unsigned int val)
462 {
463 	return CALL_RAW_FUNC(codec, reg_raw_write(codec, reg, val));
464 }
465 EXPORT_SYMBOL_GPL(snd_hdac_regmap_write_raw);
466 
467 static int reg_raw_read(struct hdac_device *codec, unsigned int reg,
468 			unsigned int *val, bool uncached)
469 {
470 	int err;
471 
472 	mutex_lock(&codec->regmap_lock);
473 	if (uncached || !codec->regmap)
474 		err = hda_reg_read(codec, reg, val);
475 	else
476 		err = regmap_read(codec->regmap, reg, val);
477 	mutex_unlock(&codec->regmap_lock);
478 	return err;
479 }
480 
481 static int __snd_hdac_regmap_read_raw(struct hdac_device *codec,
482 				      unsigned int reg, unsigned int *val,
483 				      bool uncached)
484 {
485 	return CALL_RAW_FUNC(codec, reg_raw_read(codec, reg, val, uncached));
486 }
487 
488 /**
489  * snd_hdac_regmap_read_raw - read a pseudo register with power mgmt
490  * @codec: the codec object
491  * @reg: pseudo register
492  * @val: pointer to store the read value
493  *
494  * Returns zero if successful or a negative error code.
495  */
496 int snd_hdac_regmap_read_raw(struct hdac_device *codec, unsigned int reg,
497 			     unsigned int *val)
498 {
499 	return __snd_hdac_regmap_read_raw(codec, reg, val, false);
500 }
501 EXPORT_SYMBOL_GPL(snd_hdac_regmap_read_raw);
502 
503 /* Works like snd_hdac_regmap_read_raw(), but this doesn't read from the
504  * cache but always via hda verbs.
505  */
506 int snd_hdac_regmap_read_raw_uncached(struct hdac_device *codec,
507 				      unsigned int reg, unsigned int *val)
508 {
509 	return __snd_hdac_regmap_read_raw(codec, reg, val, true);
510 }
511 
512 static int reg_raw_update(struct hdac_device *codec, unsigned int reg,
513 			  unsigned int mask, unsigned int val)
514 {
515 	unsigned int orig;
516 	bool change;
517 	int err;
518 
519 	mutex_lock(&codec->regmap_lock);
520 	if (codec->regmap) {
521 		err = regmap_update_bits_check(codec->regmap, reg, mask, val,
522 					       &change);
523 		if (!err)
524 			err = change ? 1 : 0;
525 	} else {
526 		err = hda_reg_read(codec, reg, &orig);
527 		if (!err) {
528 			val &= mask;
529 			val |= orig & ~mask;
530 			if (val != orig) {
531 				err = hda_reg_write(codec, reg, val);
532 				if (!err)
533 					err = 1;
534 			}
535 		}
536 	}
537 	mutex_unlock(&codec->regmap_lock);
538 	return err;
539 }
540 
541 /**
542  * snd_hdac_regmap_update_raw - update a pseudo register with power mgmt
543  * @codec: the codec object
544  * @reg: pseudo register
545  * @mask: bit mask to update
546  * @val: value to update
547  *
548  * Returns zero if successful or a negative error code.
549  */
550 int snd_hdac_regmap_update_raw(struct hdac_device *codec, unsigned int reg,
551 			       unsigned int mask, unsigned int val)
552 {
553 	return CALL_RAW_FUNC(codec, reg_raw_update(codec, reg, mask, val));
554 }
555 EXPORT_SYMBOL_GPL(snd_hdac_regmap_update_raw);
556 
557 static int reg_raw_update_once(struct hdac_device *codec, unsigned int reg,
558 			       unsigned int mask, unsigned int val)
559 {
560 	unsigned int orig;
561 	int err;
562 
563 	if (!codec->regmap)
564 		return reg_raw_update(codec, reg, mask, val);
565 
566 	mutex_lock(&codec->regmap_lock);
567 	regcache_cache_only(codec->regmap, true);
568 	err = regmap_read(codec->regmap, reg, &orig);
569 	regcache_cache_only(codec->regmap, false);
570 	if (err < 0)
571 		err = regmap_update_bits(codec->regmap, reg, mask, val);
572 	mutex_unlock(&codec->regmap_lock);
573 	return err;
574 }
575 
576 /**
577  * snd_hdac_regmap_update_raw_once - initialize the register value only once
578  * @codec: the codec object
579  * @reg: pseudo register
580  * @mask: bit mask to update
581  * @val: value to update
582  *
583  * Performs the update of the register bits only once when the register
584  * hasn't been initialized yet.  Used in HD-audio legacy driver.
585  * Returns zero if successful or a negative error code
586  */
587 int snd_hdac_regmap_update_raw_once(struct hdac_device *codec, unsigned int reg,
588 				    unsigned int mask, unsigned int val)
589 {
590 	return CALL_RAW_FUNC(codec, reg_raw_update_once(codec, reg, mask, val));
591 }
592 EXPORT_SYMBOL_GPL(snd_hdac_regmap_update_raw_once);
593 
594 /**
595  * snd_hdac_regmap_sync - sync out the cached values for PM resume
596  * @codec: the codec object
597  */
598 void snd_hdac_regmap_sync(struct hdac_device *codec)
599 {
600 	if (codec->regmap) {
601 		mutex_lock(&codec->regmap_lock);
602 		regcache_sync(codec->regmap);
603 		mutex_unlock(&codec->regmap_lock);
604 	}
605 }
606 EXPORT_SYMBOL_GPL(snd_hdac_regmap_sync);
607