xref: /linux/sound/soc/sh/rcar/adg.c (revision 18ca45f5ba1e31704bcca038b8b612e9b1f52b4f)
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;
68 
69 	if (!div)
70 		return 0;
71 
72 	for (i = 3; i >= 0; i--) {
73 		int 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 sel;
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 		int idx = 0;
130 		int step = 2;
131 		int div;
132 
133 		if (!sel_rate[sel])
134 			continue;
135 
136 		for (div = 2; div <= 98304; div += step) {
137 			diff = abs(target_rate - sel_rate[sel] / div);
138 			if (min > diff) {
139 				val = (sel << 8) | idx;
140 				min = diff;
141 				en = 1 << (sel + 1); /* fixme */
142 			}
143 
144 			/*
145 			 * step of 0_0000 / 0_0001 / 0_1101
146 			 * are out of order
147 			 */
148 			if ((idx > 2) && (idx % 2))
149 				step *= 2;
150 			if (idx == 0x1c) {
151 				div += step;
152 				step *= 2;
153 			}
154 			idx++;
155 		}
156 	}
157 
158 	if (min == ~0) {
159 		dev_err(dev, "no Input clock\n");
160 		return;
161 	}
162 
163 	*target_val = val;
164 	if (target_en)
165 		*target_en = en;
166 }
167 
168 static void rsnd_adg_get_timesel_ratio(struct rsnd_priv *priv,
169 				       struct rsnd_dai_stream *io,
170 				       unsigned int in_rate,
171 				       unsigned int out_rate,
172 				       u32 *in, u32 *out, u32 *en)
173 {
174 	struct snd_pcm_runtime *runtime = rsnd_io_to_runtime(io);
175 	unsigned int target_rate;
176 	u32 *target_val;
177 	u32 _in;
178 	u32 _out;
179 	u32 _en;
180 
181 	/* default = SSI WS */
182 	_in =
183 	_out = rsnd_adg_ssi_ws_timing_gen2(io);
184 
185 	target_rate = 0;
186 	target_val = NULL;
187 	_en = 0;
188 	if (runtime->rate != in_rate) {
189 		target_rate = out_rate;
190 		target_val  = &_out;
191 	} else if (runtime->rate != out_rate) {
192 		target_rate = in_rate;
193 		target_val  = &_in;
194 	}
195 
196 	if (target_rate)
197 		__rsnd_adg_get_timesel_ratio(priv, io,
198 					     target_rate,
199 					     target_val, &_en);
200 
201 	if (in)
202 		*in = _in;
203 	if (out)
204 		*out = _out;
205 	if (en)
206 		*en = _en;
207 }
208 
209 int rsnd_adg_set_cmd_timsel_gen2(struct rsnd_mod *cmd_mod,
210 				 struct rsnd_dai_stream *io)
211 {
212 	struct rsnd_priv *priv = rsnd_mod_to_priv(cmd_mod);
213 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
214 	struct rsnd_mod *adg_mod = rsnd_mod_get(adg);
215 	int id = rsnd_mod_id(cmd_mod);
216 	int shift = (id % 2) ? 16 : 0;
217 	u32 mask, val;
218 
219 	rsnd_adg_get_timesel_ratio(priv, io,
220 				   rsnd_src_get_in_rate(priv, io),
221 				   rsnd_src_get_out_rate(priv, io),
222 				   NULL, &val, NULL);
223 
224 	val  = val	<< shift;
225 	mask = 0x0f1f	<< shift;
226 
227 	rsnd_mod_bset(adg_mod, CMDOUT_TIMSEL, mask, val);
228 
229 	return 0;
230 }
231 
232 int rsnd_adg_set_src_timesel_gen2(struct rsnd_mod *src_mod,
233 				  struct rsnd_dai_stream *io,
234 				  unsigned int in_rate,
235 				  unsigned int out_rate)
236 {
237 	struct rsnd_priv *priv = rsnd_mod_to_priv(src_mod);
238 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
239 	struct rsnd_mod *adg_mod = rsnd_mod_get(adg);
240 	u32 in, out;
241 	u32 mask, en;
242 	int id = rsnd_mod_id(src_mod);
243 	int shift = (id % 2) ? 16 : 0;
244 
245 	rsnd_mod_confirm_src(src_mod);
246 
247 	rsnd_adg_get_timesel_ratio(priv, io,
248 				   in_rate, out_rate,
249 				   &in, &out, &en);
250 
251 	in   = in	<< shift;
252 	out  = out	<< shift;
253 	mask = 0x0f1f	<< shift;
254 
255 	rsnd_mod_bset(adg_mod, SRCIN_TIMSEL(id / 2),  mask, in);
256 	rsnd_mod_bset(adg_mod, SRCOUT_TIMSEL(id / 2), mask, out);
257 
258 	if (en)
259 		rsnd_mod_bset(adg_mod, DIV_EN, en, en);
260 
261 	return 0;
262 }
263 
264 static void rsnd_adg_set_ssi_clk(struct rsnd_mod *ssi_mod, u32 val)
265 {
266 	struct rsnd_priv *priv = rsnd_mod_to_priv(ssi_mod);
267 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
268 	struct rsnd_mod *adg_mod = rsnd_mod_get(adg);
269 	struct device *dev = rsnd_priv_to_dev(priv);
270 	int id = rsnd_mod_id(ssi_mod);
271 	int shift = (id % 4) * 8;
272 	u32 mask = 0xFF << shift;
273 
274 	rsnd_mod_confirm_ssi(ssi_mod);
275 
276 	val = val << shift;
277 
278 	/*
279 	 * SSI 8 is not connected to ADG.
280 	 * it works with SSI 7
281 	 */
282 	if (id == 8)
283 		return;
284 
285 	rsnd_mod_bset(adg_mod, AUDIO_CLK_SEL(id / 4), mask, val);
286 
287 	dev_dbg(dev, "AUDIO_CLK_SEL is 0x%x\n", val);
288 }
289 
290 int rsnd_adg_clk_query(struct rsnd_priv *priv, unsigned int rate)
291 {
292 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
293 	struct clk *clk;
294 	int i;
295 	int sel_table[] = {
296 		[CLKA] = 0x1,
297 		[CLKB] = 0x2,
298 		[CLKC] = 0x3,
299 		[CLKI] = 0x0,
300 	};
301 
302 	/*
303 	 * find suitable clock from
304 	 * AUDIO_CLKA/AUDIO_CLKB/AUDIO_CLKC/AUDIO_CLKI.
305 	 */
306 	for_each_rsnd_clk(clk, adg, i) {
307 		if (rate == adg->clk_rate[i])
308 			return sel_table[i];
309 	}
310 
311 	/*
312 	 * find divided clock from BRGA/BRGB
313 	 */
314 	if (rate == adg->rbga_rate_for_441khz)
315 		return 0x10;
316 
317 	if (rate == adg->rbgb_rate_for_48khz)
318 		return 0x20;
319 
320 	return -EIO;
321 }
322 
323 int rsnd_adg_ssi_clk_stop(struct rsnd_mod *ssi_mod)
324 {
325 	rsnd_adg_set_ssi_clk(ssi_mod, 0);
326 
327 	return 0;
328 }
329 
330 int rsnd_adg_ssi_clk_try_start(struct rsnd_mod *ssi_mod, unsigned int rate)
331 {
332 	struct rsnd_priv *priv = rsnd_mod_to_priv(ssi_mod);
333 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
334 	struct device *dev = rsnd_priv_to_dev(priv);
335 	struct rsnd_mod *adg_mod = rsnd_mod_get(adg);
336 	int data;
337 	u32 ckr = 0;
338 
339 	data = rsnd_adg_clk_query(priv, rate);
340 	if (data < 0)
341 		return data;
342 
343 	rsnd_adg_set_ssi_clk(ssi_mod, data);
344 
345 	if (rsnd_flags_has(adg, LRCLK_ASYNC)) {
346 		if (rsnd_flags_has(adg, AUDIO_OUT_48))
347 			ckr = 0x80000000;
348 	} else {
349 		if (0 == (rate % 8000))
350 			ckr = 0x80000000;
351 	}
352 
353 	rsnd_mod_bset(adg_mod, BRGCKR, 0x80770000, adg->ckr | ckr);
354 	rsnd_mod_write(adg_mod, BRRA,  adg->rbga);
355 	rsnd_mod_write(adg_mod, BRRB,  adg->rbgb);
356 
357 	dev_dbg(dev, "CLKOUT is based on BRG%c (= %dHz)\n",
358 		(ckr) ? 'B' : 'A',
359 		(ckr) ?	adg->rbgb_rate_for_48khz :
360 			adg->rbga_rate_for_441khz);
361 
362 	return 0;
363 }
364 
365 void rsnd_adg_clk_control(struct rsnd_priv *priv, int enable)
366 {
367 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
368 	struct device *dev = rsnd_priv_to_dev(priv);
369 	struct clk *clk;
370 	int i;
371 
372 	for_each_rsnd_clk(clk, adg, i) {
373 		if (enable) {
374 			int 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] = 0;
382 			if (ret < 0)
383 				dev_warn(dev, "can't use clk %d\n", i);
384 			else
385 				adg->clk_rate[i] = clk_get_rate(clk);
386 		} else {
387 			if (adg->clk_rate[i])
388 				clk_disable_unprepare(clk);
389 			adg->clk_rate[i] = 0;
390 		}
391 	}
392 }
393 
394 static void rsnd_adg_get_clkin(struct rsnd_priv *priv,
395 			       struct rsnd_adg *adg)
396 {
397 	struct device *dev = rsnd_priv_to_dev(priv);
398 	int i;
399 
400 	for (i = 0; i < CLKMAX; i++) {
401 		struct clk *clk = devm_clk_get(dev, clk_name[i]);
402 
403 		adg->clk[i] = IS_ERR(clk) ? NULL : clk;
404 	}
405 }
406 
407 static void rsnd_adg_get_clkout(struct rsnd_priv *priv,
408 				struct rsnd_adg *adg)
409 {
410 	struct clk *clk;
411 	struct device *dev = rsnd_priv_to_dev(priv);
412 	struct device_node *np = dev->of_node;
413 	struct property *prop;
414 	u32 ckr, rbgx, rbga, rbgb;
415 	u32 rate, div;
416 #define REQ_SIZE 2
417 	u32 req_rate[REQ_SIZE] = {};
418 	uint32_t count = 0;
419 	unsigned long req_48kHz_rate, req_441kHz_rate;
420 	int i, req_size;
421 	const char *parent_clk_name = NULL;
422 	static const char * const clkout_name[] = {
423 		[CLKOUT]  = "audio_clkout",
424 		[CLKOUT1] = "audio_clkout1",
425 		[CLKOUT2] = "audio_clkout2",
426 		[CLKOUT3] = "audio_clkout3",
427 	};
428 	int brg_table[] = {
429 		[CLKA] = 0x0,
430 		[CLKB] = 0x1,
431 		[CLKC] = 0x4,
432 		[CLKI] = 0x2,
433 	};
434 
435 	ckr = 0;
436 	rbga = 2; /* default 1/6 */
437 	rbgb = 2; /* default 1/6 */
438 
439 	/*
440 	 * ADG supports BRRA/BRRB output only
441 	 * this means all clkout0/1/2/3 will be same rate
442 	 */
443 	prop = of_find_property(np, "clock-frequency", NULL);
444 	if (!prop)
445 		goto rsnd_adg_get_clkout_end;
446 
447 	req_size = prop->length / sizeof(u32);
448 	if (req_size > REQ_SIZE) {
449 		dev_err(dev,
450 			"too many clock-frequency, use top %d\n", REQ_SIZE);
451 		req_size = REQ_SIZE;
452 	}
453 
454 	of_property_read_u32_array(np, "clock-frequency", req_rate, req_size);
455 	req_48kHz_rate = 0;
456 	req_441kHz_rate = 0;
457 	for (i = 0; i < req_size; i++) {
458 		if (0 == (req_rate[i] % 44100))
459 			req_441kHz_rate = req_rate[i];
460 		if (0 == (req_rate[i] % 48000))
461 			req_48kHz_rate = req_rate[i];
462 	}
463 
464 	if (req_rate[0] % 48000 == 0)
465 		rsnd_flags_set(adg, AUDIO_OUT_48);
466 
467 	if (of_get_property(np, "clkout-lr-asynchronous", NULL))
468 		rsnd_flags_set(adg, LRCLK_ASYNC);
469 
470 	/*
471 	 * This driver is assuming that AUDIO_CLKA/AUDIO_CLKB/AUDIO_CLKC
472 	 * have 44.1kHz or 48kHz base clocks for now.
473 	 *
474 	 * SSI itself can divide parent clock by 1/1 - 1/16
475 	 * see
476 	 *	rsnd_adg_ssi_clk_try_start()
477 	 *	rsnd_ssi_master_clk_start()
478 	 */
479 	adg->rbga_rate_for_441khz	= 0;
480 	adg->rbgb_rate_for_48khz	= 0;
481 	for_each_rsnd_clk(clk, adg, i) {
482 		rate = clk_get_rate(clk);
483 
484 		if (0 == rate) /* not used */
485 			continue;
486 
487 		/* RBGA */
488 		if (!adg->rbga_rate_for_441khz && (0 == rate % 44100)) {
489 			div = 6;
490 			if (req_441kHz_rate)
491 				div = rate / req_441kHz_rate;
492 			rbgx = rsnd_adg_calculate_rbgx(div);
493 			if (BRRx_MASK(rbgx) == rbgx) {
494 				rbga = rbgx;
495 				adg->rbga_rate_for_441khz = rate / div;
496 				ckr |= brg_table[i] << 20;
497 				if (req_441kHz_rate &&
498 				    !rsnd_flags_has(adg, AUDIO_OUT_48))
499 					parent_clk_name = __clk_get_name(clk);
500 			}
501 		}
502 
503 		/* RBGB */
504 		if (!adg->rbgb_rate_for_48khz && (0 == rate % 48000)) {
505 			div = 6;
506 			if (req_48kHz_rate)
507 				div = rate / req_48kHz_rate;
508 			rbgx = rsnd_adg_calculate_rbgx(div);
509 			if (BRRx_MASK(rbgx) == rbgx) {
510 				rbgb = rbgx;
511 				adg->rbgb_rate_for_48khz = rate / div;
512 				ckr |= brg_table[i] << 16;
513 				if (req_48kHz_rate &&
514 				    rsnd_flags_has(adg, AUDIO_OUT_48))
515 					parent_clk_name = __clk_get_name(clk);
516 			}
517 		}
518 	}
519 
520 	/*
521 	 * ADG supports BRRA/BRRB output only.
522 	 * this means all clkout0/1/2/3 will be * same rate
523 	 */
524 
525 	of_property_read_u32(np, "#clock-cells", &count);
526 	/*
527 	 * for clkout
528 	 */
529 	if (!count) {
530 		clk = clk_register_fixed_rate(dev, clkout_name[CLKOUT],
531 					      parent_clk_name, 0, req_rate[0]);
532 		if (!IS_ERR(clk)) {
533 			adg->clkout[CLKOUT] = clk;
534 			of_clk_add_provider(np, of_clk_src_simple_get, clk);
535 		}
536 	}
537 	/*
538 	 * for clkout0/1/2/3
539 	 */
540 	else {
541 		for (i = 0; i < CLKOUTMAX; i++) {
542 			clk = clk_register_fixed_rate(dev, clkout_name[i],
543 						      parent_clk_name, 0,
544 						      req_rate[0]);
545 			if (!IS_ERR(clk))
546 				adg->clkout[i] = clk;
547 		}
548 		adg->onecell.clks	= adg->clkout;
549 		adg->onecell.clk_num	= CLKOUTMAX;
550 		of_clk_add_provider(np, of_clk_src_onecell_get,
551 				    &adg->onecell);
552 	}
553 
554 rsnd_adg_get_clkout_end:
555 	adg->ckr = ckr;
556 	adg->rbga = rbga;
557 	adg->rbgb = rbgb;
558 }
559 
560 #ifdef DEBUG
561 static void rsnd_adg_clk_dbg_info(struct rsnd_priv *priv, struct rsnd_adg *adg)
562 {
563 	struct device *dev = rsnd_priv_to_dev(priv);
564 	struct clk *clk;
565 	int i;
566 
567 	for_each_rsnd_clk(clk, adg, i)
568 		dev_dbg(dev, "%s    : %pa : %ld\n",
569 			clk_name[i], clk, clk_get_rate(clk));
570 
571 	dev_dbg(dev, "BRGCKR = 0x%08x, BRRA/BRRB = 0x%x/0x%x\n",
572 		adg->ckr, adg->rbga, adg->rbgb);
573 	dev_dbg(dev, "BRGA (for 44100 base) = %d\n", adg->rbga_rate_for_441khz);
574 	dev_dbg(dev, "BRGB (for 48000 base) = %d\n", adg->rbgb_rate_for_48khz);
575 
576 	/*
577 	 * Actual CLKOUT will be exchanged in rsnd_adg_ssi_clk_try_start()
578 	 * by BRGCKR::BRGCKR_31
579 	 */
580 	for_each_rsnd_clkout(clk, adg, i)
581 		dev_dbg(dev, "clkout %d : %pa : %ld\n", i,
582 			clk, clk_get_rate(clk));
583 }
584 #else
585 #define rsnd_adg_clk_dbg_info(priv, adg)
586 #endif
587 
588 int rsnd_adg_probe(struct rsnd_priv *priv)
589 {
590 	struct rsnd_adg *adg;
591 	struct device *dev = rsnd_priv_to_dev(priv);
592 	int ret;
593 
594 	adg = devm_kzalloc(dev, sizeof(*adg), GFP_KERNEL);
595 	if (!adg)
596 		return -ENOMEM;
597 
598 	ret = rsnd_mod_init(priv, &adg->mod, &adg_ops,
599 		      NULL, 0, 0);
600 	if (ret)
601 		return ret;
602 
603 	rsnd_adg_get_clkin(priv, adg);
604 	rsnd_adg_get_clkout(priv, adg);
605 	rsnd_adg_clk_dbg_info(priv, adg);
606 
607 	priv->adg = adg;
608 
609 	rsnd_adg_clk_enable(priv);
610 
611 	return 0;
612 }
613 
614 void rsnd_adg_remove(struct rsnd_priv *priv)
615 {
616 	struct device *dev = rsnd_priv_to_dev(priv);
617 	struct device_node *np = dev->of_node;
618 	struct rsnd_adg *adg = priv->adg;
619 	struct clk *clk;
620 	int i;
621 
622 	for_each_rsnd_clkout(clk, adg, i)
623 		if (adg->clkout[i])
624 			clk_unregister_fixed_rate(adg->clkout[i]);
625 
626 	of_clk_del_provider(np);
627 
628 	rsnd_adg_clk_disable(priv);
629 }
630