xref: /openbmc/linux/sound/soc/sh/rcar/adg.c (revision 9b93eb47)
1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Helper routines for R-Car sound ADG.
4 //
5 //  Copyright (C) 2013  Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
6 
7 #include <linux/clk-provider.h>
8 #include "rsnd.h"
9 
10 #define CLKA	0
11 #define CLKB	1
12 #define CLKC	2
13 #define CLKI	3
14 #define CLKMAX	4
15 
16 #define CLKOUT	0
17 #define CLKOUT1	1
18 #define CLKOUT2	2
19 #define CLKOUT3	3
20 #define CLKOUTMAX 4
21 
22 #define BRRx_MASK(x) (0x3FF & x)
23 
24 static struct rsnd_mod_ops adg_ops = {
25 	.name = "adg",
26 };
27 
28 struct rsnd_adg {
29 	struct clk *clk[CLKMAX];
30 	struct clk *clkout[CLKOUTMAX];
31 	struct clk_onecell_data onecell;
32 	struct rsnd_mod mod;
33 	u32 flags;
34 	u32 ckr;
35 	u32 rbga;
36 	u32 rbgb;
37 
38 	int rbga_rate_for_441khz; /* RBGA */
39 	int rbgb_rate_for_48khz;  /* RBGB */
40 };
41 
42 #define LRCLK_ASYNC	(1 << 0)
43 #define AUDIO_OUT_48	(1 << 1)
44 
45 #define for_each_rsnd_clk(pos, adg, i)		\
46 	for (i = 0;				\
47 	     (i < CLKMAX) &&			\
48 	     ((pos) = adg->clk[i]);		\
49 	     i++)
50 #define for_each_rsnd_clkout(pos, adg, i)	\
51 	for (i = 0;				\
52 	     (i < CLKOUTMAX) &&			\
53 	     ((pos) = adg->clkout[i]);	\
54 	     i++)
55 #define rsnd_priv_to_adg(priv) ((struct rsnd_adg *)(priv)->adg)
56 
57 static const char * const clk_name[] = {
58 	[CLKA]	= "clk_a",
59 	[CLKB]	= "clk_b",
60 	[CLKC]	= "clk_c",
61 	[CLKI]	= "clk_i",
62 };
63 
64 static u32 rsnd_adg_calculate_rbgx(unsigned long div)
65 {
66 	int i, ratio;
67 
68 	if (!div)
69 		return 0;
70 
71 	for (i = 3; i >= 0; i--) {
72 		ratio = 2 << (i * 2);
73 		if (0 == (div % ratio))
74 			return (u32)((i << 8) | ((div / ratio) - 1));
75 	}
76 
77 	return ~0;
78 }
79 
80 static u32 rsnd_adg_ssi_ws_timing_gen2(struct rsnd_dai_stream *io)
81 {
82 	struct rsnd_mod *ssi_mod = rsnd_io_to_mod_ssi(io);
83 	int id = rsnd_mod_id(ssi_mod);
84 	int ws = id;
85 
86 	if (rsnd_ssi_is_pin_sharing(io)) {
87 		switch (id) {
88 		case 1:
89 		case 2:
90 			ws = 0;
91 			break;
92 		case 4:
93 			ws = 3;
94 			break;
95 		case 8:
96 			ws = 7;
97 			break;
98 		}
99 	}
100 
101 	return (0x6 + ws) << 8;
102 }
103 
104 static void __rsnd_adg_get_timesel_ratio(struct rsnd_priv *priv,
105 				       struct rsnd_dai_stream *io,
106 				       unsigned int target_rate,
107 				       unsigned int *target_val,
108 				       unsigned int *target_en)
109 {
110 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
111 	struct device *dev = rsnd_priv_to_dev(priv);
112 	int idx, sel, div, step;
113 	unsigned int val, en;
114 	unsigned int min, diff;
115 	unsigned int sel_rate[] = {
116 		clk_get_rate(adg->clk[CLKA]),	/* 0000: CLKA */
117 		clk_get_rate(adg->clk[CLKB]),	/* 0001: CLKB */
118 		clk_get_rate(adg->clk[CLKC]),	/* 0010: CLKC */
119 		adg->rbga_rate_for_441khz,	/* 0011: RBGA */
120 		adg->rbgb_rate_for_48khz,	/* 0100: RBGB */
121 	};
122 
123 	min = ~0;
124 	val = 0;
125 	en = 0;
126 	for (sel = 0; sel < ARRAY_SIZE(sel_rate); sel++) {
127 		idx = 0;
128 		step = 2;
129 
130 		if (!sel_rate[sel])
131 			continue;
132 
133 		for (div = 2; div <= 98304; div += step) {
134 			diff = abs(target_rate - sel_rate[sel] / div);
135 			if (min > diff) {
136 				val = (sel << 8) | idx;
137 				min = diff;
138 				en = 1 << (sel + 1); /* fixme */
139 			}
140 
141 			/*
142 			 * step of 0_0000 / 0_0001 / 0_1101
143 			 * are out of order
144 			 */
145 			if ((idx > 2) && (idx % 2))
146 				step *= 2;
147 			if (idx == 0x1c) {
148 				div += step;
149 				step *= 2;
150 			}
151 			idx++;
152 		}
153 	}
154 
155 	if (min == ~0) {
156 		dev_err(dev, "no Input clock\n");
157 		return;
158 	}
159 
160 	*target_val = val;
161 	if (target_en)
162 		*target_en = en;
163 }
164 
165 static void rsnd_adg_get_timesel_ratio(struct rsnd_priv *priv,
166 				       struct rsnd_dai_stream *io,
167 				       unsigned int in_rate,
168 				       unsigned int out_rate,
169 				       u32 *in, u32 *out, u32 *en)
170 {
171 	struct snd_pcm_runtime *runtime = rsnd_io_to_runtime(io);
172 	unsigned int target_rate;
173 	u32 *target_val;
174 	u32 _in;
175 	u32 _out;
176 	u32 _en;
177 
178 	/* default = SSI WS */
179 	_in =
180 	_out = rsnd_adg_ssi_ws_timing_gen2(io);
181 
182 	target_rate = 0;
183 	target_val = NULL;
184 	_en = 0;
185 	if (runtime->rate != in_rate) {
186 		target_rate = out_rate;
187 		target_val  = &_out;
188 	} else if (runtime->rate != out_rate) {
189 		target_rate = in_rate;
190 		target_val  = &_in;
191 	}
192 
193 	if (target_rate)
194 		__rsnd_adg_get_timesel_ratio(priv, io,
195 					     target_rate,
196 					     target_val, &_en);
197 
198 	if (in)
199 		*in = _in;
200 	if (out)
201 		*out = _out;
202 	if (en)
203 		*en = _en;
204 }
205 
206 int rsnd_adg_set_cmd_timsel_gen2(struct rsnd_mod *cmd_mod,
207 				 struct rsnd_dai_stream *io)
208 {
209 	struct rsnd_priv *priv = rsnd_mod_to_priv(cmd_mod);
210 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
211 	struct rsnd_mod *adg_mod = rsnd_mod_get(adg);
212 	int id = rsnd_mod_id(cmd_mod);
213 	int shift = (id % 2) ? 16 : 0;
214 	u32 mask, val;
215 
216 	rsnd_adg_get_timesel_ratio(priv, io,
217 				   rsnd_src_get_in_rate(priv, io),
218 				   rsnd_src_get_out_rate(priv, io),
219 				   NULL, &val, NULL);
220 
221 	val  = val	<< shift;
222 	mask = 0x0f1f	<< shift;
223 
224 	rsnd_mod_bset(adg_mod, CMDOUT_TIMSEL, mask, val);
225 
226 	return 0;
227 }
228 
229 int rsnd_adg_set_src_timesel_gen2(struct rsnd_mod *src_mod,
230 				  struct rsnd_dai_stream *io,
231 				  unsigned int in_rate,
232 				  unsigned int out_rate)
233 {
234 	struct rsnd_priv *priv = rsnd_mod_to_priv(src_mod);
235 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
236 	struct rsnd_mod *adg_mod = rsnd_mod_get(adg);
237 	u32 in, out;
238 	u32 mask, en;
239 	int id = rsnd_mod_id(src_mod);
240 	int shift = (id % 2) ? 16 : 0;
241 
242 	rsnd_mod_confirm_src(src_mod);
243 
244 	rsnd_adg_get_timesel_ratio(priv, io,
245 				   in_rate, out_rate,
246 				   &in, &out, &en);
247 
248 	in   = in	<< shift;
249 	out  = out	<< shift;
250 	mask = 0x0f1f	<< shift;
251 
252 	rsnd_mod_bset(adg_mod, SRCIN_TIMSEL(id / 2),  mask, in);
253 	rsnd_mod_bset(adg_mod, SRCOUT_TIMSEL(id / 2), mask, out);
254 
255 	if (en)
256 		rsnd_mod_bset(adg_mod, DIV_EN, en, en);
257 
258 	return 0;
259 }
260 
261 static void rsnd_adg_set_ssi_clk(struct rsnd_mod *ssi_mod, u32 val)
262 {
263 	struct rsnd_priv *priv = rsnd_mod_to_priv(ssi_mod);
264 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
265 	struct rsnd_mod *adg_mod = rsnd_mod_get(adg);
266 	struct device *dev = rsnd_priv_to_dev(priv);
267 	int id = rsnd_mod_id(ssi_mod);
268 	int shift = (id % 4) * 8;
269 	u32 mask = 0xFF << shift;
270 
271 	rsnd_mod_confirm_ssi(ssi_mod);
272 
273 	val = val << shift;
274 
275 	/*
276 	 * SSI 8 is not connected to ADG.
277 	 * it works with SSI 7
278 	 */
279 	if (id == 8)
280 		return;
281 
282 	rsnd_mod_bset(adg_mod, AUDIO_CLK_SEL(id / 4), mask, val);
283 
284 	dev_dbg(dev, "AUDIO_CLK_SEL is 0x%x\n", val);
285 }
286 
287 int rsnd_adg_clk_query(struct rsnd_priv *priv, unsigned int rate)
288 {
289 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
290 	struct clk *clk;
291 	int i;
292 	int sel_table[] = {
293 		[CLKA] = 0x1,
294 		[CLKB] = 0x2,
295 		[CLKC] = 0x3,
296 		[CLKI] = 0x0,
297 	};
298 
299 	/*
300 	 * find suitable clock from
301 	 * AUDIO_CLKA/AUDIO_CLKB/AUDIO_CLKC/AUDIO_CLKI.
302 	 */
303 	for_each_rsnd_clk(clk, adg, i) {
304 		if (rate == clk_get_rate(clk))
305 			return sel_table[i];
306 	}
307 
308 	/*
309 	 * find divided clock from BRGA/BRGB
310 	 */
311 	if (rate == adg->rbga_rate_for_441khz)
312 		return 0x10;
313 
314 	if (rate == adg->rbgb_rate_for_48khz)
315 		return 0x20;
316 
317 	return -EIO;
318 }
319 
320 int rsnd_adg_ssi_clk_stop(struct rsnd_mod *ssi_mod)
321 {
322 	rsnd_adg_set_ssi_clk(ssi_mod, 0);
323 
324 	return 0;
325 }
326 
327 int rsnd_adg_ssi_clk_try_start(struct rsnd_mod *ssi_mod, unsigned int rate)
328 {
329 	struct rsnd_priv *priv = rsnd_mod_to_priv(ssi_mod);
330 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
331 	struct device *dev = rsnd_priv_to_dev(priv);
332 	struct rsnd_mod *adg_mod = rsnd_mod_get(adg);
333 	int data;
334 	u32 ckr = 0;
335 
336 	data = rsnd_adg_clk_query(priv, rate);
337 	if (data < 0)
338 		return data;
339 
340 	rsnd_adg_set_ssi_clk(ssi_mod, data);
341 
342 	if (rsnd_flags_has(adg, LRCLK_ASYNC)) {
343 		if (rsnd_flags_has(adg, AUDIO_OUT_48))
344 			ckr = 0x80000000;
345 	} else {
346 		if (0 == (rate % 8000))
347 			ckr = 0x80000000;
348 	}
349 
350 	rsnd_mod_bset(adg_mod, BRGCKR, 0x80770000, adg->ckr | ckr);
351 	rsnd_mod_write(adg_mod, BRRA,  adg->rbga);
352 	rsnd_mod_write(adg_mod, BRRB,  adg->rbgb);
353 
354 	dev_dbg(dev, "CLKOUT is based on BRG%c (= %dHz)\n",
355 		(ckr) ? 'B' : 'A',
356 		(ckr) ?	adg->rbgb_rate_for_48khz :
357 			adg->rbga_rate_for_441khz);
358 
359 	return 0;
360 }
361 
362 void rsnd_adg_clk_control(struct rsnd_priv *priv, int enable)
363 {
364 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
365 	struct device *dev = rsnd_priv_to_dev(priv);
366 	struct clk *clk;
367 	int i, ret;
368 
369 	for_each_rsnd_clk(clk, adg, i) {
370 		ret = 0;
371 		if (enable)
372 			ret = clk_prepare_enable(clk);
373 		else
374 			clk_disable_unprepare(clk);
375 
376 		if (ret < 0)
377 			dev_warn(dev, "can't use clk %d\n", i);
378 	}
379 }
380 
381 static void rsnd_adg_get_clkin(struct rsnd_priv *priv,
382 			       struct rsnd_adg *adg)
383 {
384 	struct device *dev = rsnd_priv_to_dev(priv);
385 	struct clk *clk;
386 	int i;
387 
388 	for (i = 0; i < CLKMAX; i++) {
389 		clk = devm_clk_get(dev, clk_name[i]);
390 		adg->clk[i] = IS_ERR(clk) ? NULL : clk;
391 	}
392 }
393 
394 static void rsnd_adg_get_clkout(struct rsnd_priv *priv,
395 				struct rsnd_adg *adg)
396 {
397 	struct clk *clk;
398 	struct device *dev = rsnd_priv_to_dev(priv);
399 	struct device_node *np = dev->of_node;
400 	struct property *prop;
401 	u32 ckr, rbgx, rbga, rbgb;
402 	u32 rate, div;
403 #define REQ_SIZE 2
404 	u32 req_rate[REQ_SIZE] = {};
405 	uint32_t count = 0;
406 	unsigned long req_48kHz_rate, req_441kHz_rate;
407 	int i, req_size;
408 	const char *parent_clk_name = NULL;
409 	static const char * const clkout_name[] = {
410 		[CLKOUT]  = "audio_clkout",
411 		[CLKOUT1] = "audio_clkout1",
412 		[CLKOUT2] = "audio_clkout2",
413 		[CLKOUT3] = "audio_clkout3",
414 	};
415 	int brg_table[] = {
416 		[CLKA] = 0x0,
417 		[CLKB] = 0x1,
418 		[CLKC] = 0x4,
419 		[CLKI] = 0x2,
420 	};
421 
422 	ckr = 0;
423 	rbga = 2; /* default 1/6 */
424 	rbgb = 2; /* default 1/6 */
425 
426 	/*
427 	 * ADG supports BRRA/BRRB output only
428 	 * this means all clkout0/1/2/3 will be same rate
429 	 */
430 	prop = of_find_property(np, "clock-frequency", NULL);
431 	if (!prop)
432 		goto rsnd_adg_get_clkout_end;
433 
434 	req_size = prop->length / sizeof(u32);
435 	if (req_size > REQ_SIZE) {
436 		dev_err(dev,
437 			"too many clock-frequency, use top %d\n", REQ_SIZE);
438 		req_size = REQ_SIZE;
439 	}
440 
441 	of_property_read_u32_array(np, "clock-frequency", req_rate, req_size);
442 	req_48kHz_rate = 0;
443 	req_441kHz_rate = 0;
444 	for (i = 0; i < req_size; i++) {
445 		if (0 == (req_rate[i] % 44100))
446 			req_441kHz_rate = req_rate[i];
447 		if (0 == (req_rate[i] % 48000))
448 			req_48kHz_rate = req_rate[i];
449 	}
450 
451 	if (req_rate[0] % 48000 == 0)
452 		rsnd_flags_set(adg, AUDIO_OUT_48);
453 
454 	if (of_get_property(np, "clkout-lr-asynchronous", NULL))
455 		rsnd_flags_set(adg, LRCLK_ASYNC);
456 
457 	/*
458 	 * This driver is assuming that AUDIO_CLKA/AUDIO_CLKB/AUDIO_CLKC
459 	 * have 44.1kHz or 48kHz base clocks for now.
460 	 *
461 	 * SSI itself can divide parent clock by 1/1 - 1/16
462 	 * see
463 	 *	rsnd_adg_ssi_clk_try_start()
464 	 *	rsnd_ssi_master_clk_start()
465 	 */
466 	adg->rbga_rate_for_441khz	= 0;
467 	adg->rbgb_rate_for_48khz	= 0;
468 	for_each_rsnd_clk(clk, adg, i) {
469 		rate = clk_get_rate(clk);
470 
471 		if (0 == rate) /* not used */
472 			continue;
473 
474 		/* RBGA */
475 		if (!adg->rbga_rate_for_441khz && (0 == rate % 44100)) {
476 			div = 6;
477 			if (req_441kHz_rate)
478 				div = rate / req_441kHz_rate;
479 			rbgx = rsnd_adg_calculate_rbgx(div);
480 			if (BRRx_MASK(rbgx) == rbgx) {
481 				rbga = rbgx;
482 				adg->rbga_rate_for_441khz = rate / div;
483 				ckr |= brg_table[i] << 20;
484 				if (req_441kHz_rate &&
485 				    !rsnd_flags_has(adg, AUDIO_OUT_48))
486 					parent_clk_name = __clk_get_name(clk);
487 			}
488 		}
489 
490 		/* RBGB */
491 		if (!adg->rbgb_rate_for_48khz && (0 == rate % 48000)) {
492 			div = 6;
493 			if (req_48kHz_rate)
494 				div = rate / req_48kHz_rate;
495 			rbgx = rsnd_adg_calculate_rbgx(div);
496 			if (BRRx_MASK(rbgx) == rbgx) {
497 				rbgb = rbgx;
498 				adg->rbgb_rate_for_48khz = rate / div;
499 				ckr |= brg_table[i] << 16;
500 				if (req_48kHz_rate &&
501 				    rsnd_flags_has(adg, AUDIO_OUT_48))
502 					parent_clk_name = __clk_get_name(clk);
503 			}
504 		}
505 	}
506 
507 	/*
508 	 * ADG supports BRRA/BRRB output only.
509 	 * this means all clkout0/1/2/3 will be * same rate
510 	 */
511 
512 	of_property_read_u32(np, "#clock-cells", &count);
513 	/*
514 	 * for clkout
515 	 */
516 	if (!count) {
517 		clk = clk_register_fixed_rate(dev, clkout_name[CLKOUT],
518 					      parent_clk_name, 0, req_rate[0]);
519 		if (!IS_ERR(clk)) {
520 			adg->clkout[CLKOUT] = clk;
521 			of_clk_add_provider(np, of_clk_src_simple_get, clk);
522 		}
523 	}
524 	/*
525 	 * for clkout0/1/2/3
526 	 */
527 	else {
528 		for (i = 0; i < CLKOUTMAX; i++) {
529 			clk = clk_register_fixed_rate(dev, clkout_name[i],
530 						      parent_clk_name, 0,
531 						      req_rate[0]);
532 			if (!IS_ERR(clk))
533 				adg->clkout[i] = clk;
534 		}
535 		adg->onecell.clks	= adg->clkout;
536 		adg->onecell.clk_num	= CLKOUTMAX;
537 		of_clk_add_provider(np, of_clk_src_onecell_get,
538 				    &adg->onecell);
539 	}
540 
541 rsnd_adg_get_clkout_end:
542 	adg->ckr = ckr;
543 	adg->rbga = rbga;
544 	adg->rbgb = rbgb;
545 }
546 
547 #ifdef DEBUG
548 static void rsnd_adg_clk_dbg_info(struct rsnd_priv *priv, struct rsnd_adg *adg)
549 {
550 	struct device *dev = rsnd_priv_to_dev(priv);
551 	struct clk *clk;
552 	int i;
553 
554 	for_each_rsnd_clk(clk, adg, i)
555 		dev_dbg(dev, "%s    : %pa : %ld\n",
556 			clk_name[i], clk, clk_get_rate(clk));
557 
558 	dev_dbg(dev, "BRGCKR = 0x%08x, BRRA/BRRB = 0x%x/0x%x\n",
559 		adg->ckr, adg->rbga, adg->rbgb);
560 	dev_dbg(dev, "BRGA (for 44100 base) = %d\n", adg->rbga_rate_for_441khz);
561 	dev_dbg(dev, "BRGB (for 48000 base) = %d\n", adg->rbgb_rate_for_48khz);
562 
563 	/*
564 	 * Actual CLKOUT will be exchanged in rsnd_adg_ssi_clk_try_start()
565 	 * by BRGCKR::BRGCKR_31
566 	 */
567 	for_each_rsnd_clkout(clk, adg, i)
568 		dev_dbg(dev, "clkout %d : %pa : %ld\n", i,
569 			clk, clk_get_rate(clk));
570 }
571 #else
572 #define rsnd_adg_clk_dbg_info(priv, adg)
573 #endif
574 
575 int rsnd_adg_probe(struct rsnd_priv *priv)
576 {
577 	struct rsnd_adg *adg;
578 	struct device *dev = rsnd_priv_to_dev(priv);
579 	int ret;
580 
581 	adg = devm_kzalloc(dev, sizeof(*adg), GFP_KERNEL);
582 	if (!adg)
583 		return -ENOMEM;
584 
585 	ret = rsnd_mod_init(priv, &adg->mod, &adg_ops,
586 		      NULL, 0, 0);
587 	if (ret)
588 		return ret;
589 
590 	rsnd_adg_get_clkin(priv, adg);
591 	rsnd_adg_get_clkout(priv, adg);
592 	rsnd_adg_clk_dbg_info(priv, adg);
593 
594 	priv->adg = adg;
595 
596 	rsnd_adg_clk_enable(priv);
597 
598 	return 0;
599 }
600 
601 void rsnd_adg_remove(struct rsnd_priv *priv)
602 {
603 	struct device *dev = rsnd_priv_to_dev(priv);
604 	struct device_node *np = dev->of_node;
605 	struct rsnd_adg *adg = priv->adg;
606 	struct clk *clk;
607 	int i;
608 
609 	for_each_rsnd_clkout(clk, adg, i)
610 		if (adg->clkout[i])
611 			clk_unregister_fixed_rate(adg->clkout[i]);
612 
613 	of_clk_del_provider(np);
614 
615 	rsnd_adg_clk_disable(priv);
616 }
617