xref: /openbmc/linux/sound/soc/sh/rcar/adg.c (revision 6c33a6f4)
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 	int clk_rate[CLKMAX];
34 	u32 flags;
35 	u32 ckr;
36 	u32 rbga;
37 	u32 rbgb;
38 
39 	int rbga_rate_for_441khz; /* RBGA */
40 	int rbgb_rate_for_48khz;  /* RBGB */
41 };
42 
43 #define LRCLK_ASYNC	(1 << 0)
44 #define AUDIO_OUT_48	(1 << 1)
45 
46 #define for_each_rsnd_clk(pos, adg, i)		\
47 	for (i = 0;				\
48 	     (i < CLKMAX) &&			\
49 	     ((pos) = adg->clk[i]);		\
50 	     i++)
51 #define for_each_rsnd_clkout(pos, adg, i)	\
52 	for (i = 0;				\
53 	     (i < CLKOUTMAX) &&			\
54 	     ((pos) = adg->clkout[i]);	\
55 	     i++)
56 #define rsnd_priv_to_adg(priv) ((struct rsnd_adg *)(priv)->adg)
57 
58 static const char * const clk_name[] = {
59 	[CLKA]	= "clk_a",
60 	[CLKB]	= "clk_b",
61 	[CLKC]	= "clk_c",
62 	[CLKI]	= "clk_i",
63 };
64 
65 static u32 rsnd_adg_calculate_rbgx(unsigned long div)
66 {
67 	int i, ratio;
68 
69 	if (!div)
70 		return 0;
71 
72 	for (i = 3; i >= 0; i--) {
73 		ratio = 2 << (i * 2);
74 		if (0 == (div % ratio))
75 			return (u32)((i << 8) | ((div / ratio) - 1));
76 	}
77 
78 	return ~0;
79 }
80 
81 static u32 rsnd_adg_ssi_ws_timing_gen2(struct rsnd_dai_stream *io)
82 {
83 	struct rsnd_mod *ssi_mod = rsnd_io_to_mod_ssi(io);
84 	int id = rsnd_mod_id(ssi_mod);
85 	int ws = id;
86 
87 	if (rsnd_ssi_is_pin_sharing(io)) {
88 		switch (id) {
89 		case 1:
90 		case 2:
91 		case 9:
92 			ws = 0;
93 			break;
94 		case 4:
95 			ws = 3;
96 			break;
97 		case 8:
98 			ws = 7;
99 			break;
100 		}
101 	}
102 
103 	return (0x6 + ws) << 8;
104 }
105 
106 static void __rsnd_adg_get_timesel_ratio(struct rsnd_priv *priv,
107 				       struct rsnd_dai_stream *io,
108 				       unsigned int target_rate,
109 				       unsigned int *target_val,
110 				       unsigned int *target_en)
111 {
112 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
113 	struct device *dev = rsnd_priv_to_dev(priv);
114 	int idx, sel, div, step;
115 	unsigned int val, en;
116 	unsigned int min, diff;
117 	unsigned int sel_rate[] = {
118 		adg->clk_rate[CLKA],	/* 0000: CLKA */
119 		adg->clk_rate[CLKB],	/* 0001: CLKB */
120 		adg->clk_rate[CLKC],	/* 0010: CLKC */
121 		adg->rbga_rate_for_441khz,	/* 0011: RBGA */
122 		adg->rbgb_rate_for_48khz,	/* 0100: RBGB */
123 	};
124 
125 	min = ~0;
126 	val = 0;
127 	en = 0;
128 	for (sel = 0; sel < ARRAY_SIZE(sel_rate); sel++) {
129 		idx = 0;
130 		step = 2;
131 
132 		if (!sel_rate[sel])
133 			continue;
134 
135 		for (div = 2; div <= 98304; div += step) {
136 			diff = abs(target_rate - sel_rate[sel] / div);
137 			if (min > diff) {
138 				val = (sel << 8) | idx;
139 				min = diff;
140 				en = 1 << (sel + 1); /* fixme */
141 			}
142 
143 			/*
144 			 * step of 0_0000 / 0_0001 / 0_1101
145 			 * are out of order
146 			 */
147 			if ((idx > 2) && (idx % 2))
148 				step *= 2;
149 			if (idx == 0x1c) {
150 				div += step;
151 				step *= 2;
152 			}
153 			idx++;
154 		}
155 	}
156 
157 	if (min == ~0) {
158 		dev_err(dev, "no Input clock\n");
159 		return;
160 	}
161 
162 	*target_val = val;
163 	if (target_en)
164 		*target_en = en;
165 }
166 
167 static void rsnd_adg_get_timesel_ratio(struct rsnd_priv *priv,
168 				       struct rsnd_dai_stream *io,
169 				       unsigned int in_rate,
170 				       unsigned int out_rate,
171 				       u32 *in, u32 *out, u32 *en)
172 {
173 	struct snd_pcm_runtime *runtime = rsnd_io_to_runtime(io);
174 	unsigned int target_rate;
175 	u32 *target_val;
176 	u32 _in;
177 	u32 _out;
178 	u32 _en;
179 
180 	/* default = SSI WS */
181 	_in =
182 	_out = rsnd_adg_ssi_ws_timing_gen2(io);
183 
184 	target_rate = 0;
185 	target_val = NULL;
186 	_en = 0;
187 	if (runtime->rate != in_rate) {
188 		target_rate = out_rate;
189 		target_val  = &_out;
190 	} else if (runtime->rate != out_rate) {
191 		target_rate = in_rate;
192 		target_val  = &_in;
193 	}
194 
195 	if (target_rate)
196 		__rsnd_adg_get_timesel_ratio(priv, io,
197 					     target_rate,
198 					     target_val, &_en);
199 
200 	if (in)
201 		*in = _in;
202 	if (out)
203 		*out = _out;
204 	if (en)
205 		*en = _en;
206 }
207 
208 int rsnd_adg_set_cmd_timsel_gen2(struct rsnd_mod *cmd_mod,
209 				 struct rsnd_dai_stream *io)
210 {
211 	struct rsnd_priv *priv = rsnd_mod_to_priv(cmd_mod);
212 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
213 	struct rsnd_mod *adg_mod = rsnd_mod_get(adg);
214 	int id = rsnd_mod_id(cmd_mod);
215 	int shift = (id % 2) ? 16 : 0;
216 	u32 mask, val;
217 
218 	rsnd_adg_get_timesel_ratio(priv, io,
219 				   rsnd_src_get_in_rate(priv, io),
220 				   rsnd_src_get_out_rate(priv, io),
221 				   NULL, &val, NULL);
222 
223 	val  = val	<< shift;
224 	mask = 0x0f1f	<< shift;
225 
226 	rsnd_mod_bset(adg_mod, CMDOUT_TIMSEL, mask, val);
227 
228 	return 0;
229 }
230 
231 int rsnd_adg_set_src_timesel_gen2(struct rsnd_mod *src_mod,
232 				  struct rsnd_dai_stream *io,
233 				  unsigned int in_rate,
234 				  unsigned int out_rate)
235 {
236 	struct rsnd_priv *priv = rsnd_mod_to_priv(src_mod);
237 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
238 	struct rsnd_mod *adg_mod = rsnd_mod_get(adg);
239 	u32 in, out;
240 	u32 mask, en;
241 	int id = rsnd_mod_id(src_mod);
242 	int shift = (id % 2) ? 16 : 0;
243 
244 	rsnd_mod_confirm_src(src_mod);
245 
246 	rsnd_adg_get_timesel_ratio(priv, io,
247 				   in_rate, out_rate,
248 				   &in, &out, &en);
249 
250 	in   = in	<< shift;
251 	out  = out	<< shift;
252 	mask = 0x0f1f	<< shift;
253 
254 	rsnd_mod_bset(adg_mod, SRCIN_TIMSEL(id / 2),  mask, in);
255 	rsnd_mod_bset(adg_mod, SRCOUT_TIMSEL(id / 2), mask, out);
256 
257 	if (en)
258 		rsnd_mod_bset(adg_mod, DIV_EN, en, en);
259 
260 	return 0;
261 }
262 
263 static void rsnd_adg_set_ssi_clk(struct rsnd_mod *ssi_mod, u32 val)
264 {
265 	struct rsnd_priv *priv = rsnd_mod_to_priv(ssi_mod);
266 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
267 	struct rsnd_mod *adg_mod = rsnd_mod_get(adg);
268 	struct device *dev = rsnd_priv_to_dev(priv);
269 	int id = rsnd_mod_id(ssi_mod);
270 	int shift = (id % 4) * 8;
271 	u32 mask = 0xFF << shift;
272 
273 	rsnd_mod_confirm_ssi(ssi_mod);
274 
275 	val = val << shift;
276 
277 	/*
278 	 * SSI 8 is not connected to ADG.
279 	 * it works with SSI 7
280 	 */
281 	if (id == 8)
282 		return;
283 
284 	rsnd_mod_bset(adg_mod, AUDIO_CLK_SEL(id / 4), mask, val);
285 
286 	dev_dbg(dev, "AUDIO_CLK_SEL is 0x%x\n", val);
287 }
288 
289 int rsnd_adg_clk_query(struct rsnd_priv *priv, unsigned int rate)
290 {
291 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
292 	struct clk *clk;
293 	int i;
294 	int sel_table[] = {
295 		[CLKA] = 0x1,
296 		[CLKB] = 0x2,
297 		[CLKC] = 0x3,
298 		[CLKI] = 0x0,
299 	};
300 
301 	/*
302 	 * find suitable clock from
303 	 * AUDIO_CLKA/AUDIO_CLKB/AUDIO_CLKC/AUDIO_CLKI.
304 	 */
305 	for_each_rsnd_clk(clk, adg, i) {
306 		if (rate == adg->clk_rate[i])
307 			return sel_table[i];
308 	}
309 
310 	/*
311 	 * find divided clock from BRGA/BRGB
312 	 */
313 	if (rate == adg->rbga_rate_for_441khz)
314 		return 0x10;
315 
316 	if (rate == adg->rbgb_rate_for_48khz)
317 		return 0x20;
318 
319 	return -EIO;
320 }
321 
322 int rsnd_adg_ssi_clk_stop(struct rsnd_mod *ssi_mod)
323 {
324 	rsnd_adg_set_ssi_clk(ssi_mod, 0);
325 
326 	return 0;
327 }
328 
329 int rsnd_adg_ssi_clk_try_start(struct rsnd_mod *ssi_mod, unsigned int rate)
330 {
331 	struct rsnd_priv *priv = rsnd_mod_to_priv(ssi_mod);
332 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
333 	struct device *dev = rsnd_priv_to_dev(priv);
334 	struct rsnd_mod *adg_mod = rsnd_mod_get(adg);
335 	int data;
336 	u32 ckr = 0;
337 
338 	data = rsnd_adg_clk_query(priv, rate);
339 	if (data < 0)
340 		return data;
341 
342 	rsnd_adg_set_ssi_clk(ssi_mod, data);
343 
344 	if (rsnd_flags_has(adg, LRCLK_ASYNC)) {
345 		if (rsnd_flags_has(adg, AUDIO_OUT_48))
346 			ckr = 0x80000000;
347 	} else {
348 		if (0 == (rate % 8000))
349 			ckr = 0x80000000;
350 	}
351 
352 	rsnd_mod_bset(adg_mod, BRGCKR, 0x80770000, adg->ckr | ckr);
353 	rsnd_mod_write(adg_mod, BRRA,  adg->rbga);
354 	rsnd_mod_write(adg_mod, BRRB,  adg->rbgb);
355 
356 	dev_dbg(dev, "CLKOUT is based on BRG%c (= %dHz)\n",
357 		(ckr) ? 'B' : 'A',
358 		(ckr) ?	adg->rbgb_rate_for_48khz :
359 			adg->rbga_rate_for_441khz);
360 
361 	return 0;
362 }
363 
364 void rsnd_adg_clk_control(struct rsnd_priv *priv, int enable)
365 {
366 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
367 	struct device *dev = rsnd_priv_to_dev(priv);
368 	struct clk *clk;
369 	int i, ret;
370 
371 	for_each_rsnd_clk(clk, adg, i) {
372 		ret = 0;
373 		if (enable) {
374 			ret = clk_prepare_enable(clk);
375 
376 			/*
377 			 * We shouldn't use clk_get_rate() under
378 			 * atomic context. Let's keep it when
379 			 * rsnd_adg_clk_enable() was called
380 			 */
381 			adg->clk_rate[i] = clk_get_rate(adg->clk[i]);
382 		} else {
383 			clk_disable_unprepare(clk);
384 		}
385 
386 		if (ret < 0)
387 			dev_warn(dev, "can't use clk %d\n", i);
388 	}
389 }
390 
391 static void rsnd_adg_get_clkin(struct rsnd_priv *priv,
392 			       struct rsnd_adg *adg)
393 {
394 	struct device *dev = rsnd_priv_to_dev(priv);
395 	struct clk *clk;
396 	int i;
397 
398 	for (i = 0; i < CLKMAX; i++) {
399 		clk = devm_clk_get(dev, clk_name[i]);
400 		adg->clk[i] = IS_ERR(clk) ? NULL : clk;
401 	}
402 }
403 
404 static void rsnd_adg_get_clkout(struct rsnd_priv *priv,
405 				struct rsnd_adg *adg)
406 {
407 	struct clk *clk;
408 	struct device *dev = rsnd_priv_to_dev(priv);
409 	struct device_node *np = dev->of_node;
410 	struct property *prop;
411 	u32 ckr, rbgx, rbga, rbgb;
412 	u32 rate, div;
413 #define REQ_SIZE 2
414 	u32 req_rate[REQ_SIZE] = {};
415 	uint32_t count = 0;
416 	unsigned long req_48kHz_rate, req_441kHz_rate;
417 	int i, req_size;
418 	const char *parent_clk_name = NULL;
419 	static const char * const clkout_name[] = {
420 		[CLKOUT]  = "audio_clkout",
421 		[CLKOUT1] = "audio_clkout1",
422 		[CLKOUT2] = "audio_clkout2",
423 		[CLKOUT3] = "audio_clkout3",
424 	};
425 	int brg_table[] = {
426 		[CLKA] = 0x0,
427 		[CLKB] = 0x1,
428 		[CLKC] = 0x4,
429 		[CLKI] = 0x2,
430 	};
431 
432 	ckr = 0;
433 	rbga = 2; /* default 1/6 */
434 	rbgb = 2; /* default 1/6 */
435 
436 	/*
437 	 * ADG supports BRRA/BRRB output only
438 	 * this means all clkout0/1/2/3 will be same rate
439 	 */
440 	prop = of_find_property(np, "clock-frequency", NULL);
441 	if (!prop)
442 		goto rsnd_adg_get_clkout_end;
443 
444 	req_size = prop->length / sizeof(u32);
445 	if (req_size > REQ_SIZE) {
446 		dev_err(dev,
447 			"too many clock-frequency, use top %d\n", REQ_SIZE);
448 		req_size = REQ_SIZE;
449 	}
450 
451 	of_property_read_u32_array(np, "clock-frequency", req_rate, req_size);
452 	req_48kHz_rate = 0;
453 	req_441kHz_rate = 0;
454 	for (i = 0; i < req_size; i++) {
455 		if (0 == (req_rate[i] % 44100))
456 			req_441kHz_rate = req_rate[i];
457 		if (0 == (req_rate[i] % 48000))
458 			req_48kHz_rate = req_rate[i];
459 	}
460 
461 	if (req_rate[0] % 48000 == 0)
462 		rsnd_flags_set(adg, AUDIO_OUT_48);
463 
464 	if (of_get_property(np, "clkout-lr-asynchronous", NULL))
465 		rsnd_flags_set(adg, LRCLK_ASYNC);
466 
467 	/*
468 	 * This driver is assuming that AUDIO_CLKA/AUDIO_CLKB/AUDIO_CLKC
469 	 * have 44.1kHz or 48kHz base clocks for now.
470 	 *
471 	 * SSI itself can divide parent clock by 1/1 - 1/16
472 	 * see
473 	 *	rsnd_adg_ssi_clk_try_start()
474 	 *	rsnd_ssi_master_clk_start()
475 	 */
476 	adg->rbga_rate_for_441khz	= 0;
477 	adg->rbgb_rate_for_48khz	= 0;
478 	for_each_rsnd_clk(clk, adg, i) {
479 		rate = clk_get_rate(clk);
480 
481 		if (0 == rate) /* not used */
482 			continue;
483 
484 		/* RBGA */
485 		if (!adg->rbga_rate_for_441khz && (0 == rate % 44100)) {
486 			div = 6;
487 			if (req_441kHz_rate)
488 				div = rate / req_441kHz_rate;
489 			rbgx = rsnd_adg_calculate_rbgx(div);
490 			if (BRRx_MASK(rbgx) == rbgx) {
491 				rbga = rbgx;
492 				adg->rbga_rate_for_441khz = rate / div;
493 				ckr |= brg_table[i] << 20;
494 				if (req_441kHz_rate &&
495 				    !rsnd_flags_has(adg, AUDIO_OUT_48))
496 					parent_clk_name = __clk_get_name(clk);
497 			}
498 		}
499 
500 		/* RBGB */
501 		if (!adg->rbgb_rate_for_48khz && (0 == rate % 48000)) {
502 			div = 6;
503 			if (req_48kHz_rate)
504 				div = rate / req_48kHz_rate;
505 			rbgx = rsnd_adg_calculate_rbgx(div);
506 			if (BRRx_MASK(rbgx) == rbgx) {
507 				rbgb = rbgx;
508 				adg->rbgb_rate_for_48khz = rate / div;
509 				ckr |= brg_table[i] << 16;
510 				if (req_48kHz_rate &&
511 				    rsnd_flags_has(adg, AUDIO_OUT_48))
512 					parent_clk_name = __clk_get_name(clk);
513 			}
514 		}
515 	}
516 
517 	/*
518 	 * ADG supports BRRA/BRRB output only.
519 	 * this means all clkout0/1/2/3 will be * same rate
520 	 */
521 
522 	of_property_read_u32(np, "#clock-cells", &count);
523 	/*
524 	 * for clkout
525 	 */
526 	if (!count) {
527 		clk = clk_register_fixed_rate(dev, clkout_name[CLKOUT],
528 					      parent_clk_name, 0, req_rate[0]);
529 		if (!IS_ERR(clk)) {
530 			adg->clkout[CLKOUT] = clk;
531 			of_clk_add_provider(np, of_clk_src_simple_get, clk);
532 		}
533 	}
534 	/*
535 	 * for clkout0/1/2/3
536 	 */
537 	else {
538 		for (i = 0; i < CLKOUTMAX; i++) {
539 			clk = clk_register_fixed_rate(dev, clkout_name[i],
540 						      parent_clk_name, 0,
541 						      req_rate[0]);
542 			if (!IS_ERR(clk))
543 				adg->clkout[i] = clk;
544 		}
545 		adg->onecell.clks	= adg->clkout;
546 		adg->onecell.clk_num	= CLKOUTMAX;
547 		of_clk_add_provider(np, of_clk_src_onecell_get,
548 				    &adg->onecell);
549 	}
550 
551 rsnd_adg_get_clkout_end:
552 	adg->ckr = ckr;
553 	adg->rbga = rbga;
554 	adg->rbgb = rbgb;
555 }
556 
557 #ifdef DEBUG
558 static void rsnd_adg_clk_dbg_info(struct rsnd_priv *priv, struct rsnd_adg *adg)
559 {
560 	struct device *dev = rsnd_priv_to_dev(priv);
561 	struct clk *clk;
562 	int i;
563 
564 	for_each_rsnd_clk(clk, adg, i)
565 		dev_dbg(dev, "%s    : %pa : %ld\n",
566 			clk_name[i], clk, clk_get_rate(clk));
567 
568 	dev_dbg(dev, "BRGCKR = 0x%08x, BRRA/BRRB = 0x%x/0x%x\n",
569 		adg->ckr, adg->rbga, adg->rbgb);
570 	dev_dbg(dev, "BRGA (for 44100 base) = %d\n", adg->rbga_rate_for_441khz);
571 	dev_dbg(dev, "BRGB (for 48000 base) = %d\n", adg->rbgb_rate_for_48khz);
572 
573 	/*
574 	 * Actual CLKOUT will be exchanged in rsnd_adg_ssi_clk_try_start()
575 	 * by BRGCKR::BRGCKR_31
576 	 */
577 	for_each_rsnd_clkout(clk, adg, i)
578 		dev_dbg(dev, "clkout %d : %pa : %ld\n", i,
579 			clk, clk_get_rate(clk));
580 }
581 #else
582 #define rsnd_adg_clk_dbg_info(priv, adg)
583 #endif
584 
585 int rsnd_adg_probe(struct rsnd_priv *priv)
586 {
587 	struct rsnd_adg *adg;
588 	struct device *dev = rsnd_priv_to_dev(priv);
589 	int ret;
590 
591 	adg = devm_kzalloc(dev, sizeof(*adg), GFP_KERNEL);
592 	if (!adg)
593 		return -ENOMEM;
594 
595 	ret = rsnd_mod_init(priv, &adg->mod, &adg_ops,
596 		      NULL, 0, 0);
597 	if (ret)
598 		return ret;
599 
600 	rsnd_adg_get_clkin(priv, adg);
601 	rsnd_adg_get_clkout(priv, adg);
602 	rsnd_adg_clk_dbg_info(priv, adg);
603 
604 	priv->adg = adg;
605 
606 	rsnd_adg_clk_enable(priv);
607 
608 	return 0;
609 }
610 
611 void rsnd_adg_remove(struct rsnd_priv *priv)
612 {
613 	struct device *dev = rsnd_priv_to_dev(priv);
614 	struct device_node *np = dev->of_node;
615 	struct rsnd_adg *adg = priv->adg;
616 	struct clk *clk;
617 	int i;
618 
619 	for_each_rsnd_clkout(clk, adg, i)
620 		if (adg->clkout[i])
621 			clk_unregister_fixed_rate(adg->clkout[i]);
622 
623 	of_clk_del_provider(np);
624 
625 	rsnd_adg_clk_disable(priv);
626 }
627