xref: /linux/sound/soc/codecs/tlv320aic32x4-clk.c (revision 8e07e0e3964ca4e23ce7b68e2096fe660a888942)
1 /* SPDX-License-Identifier: GPL-2.0
2  *
3  * Clock Tree for the Texas Instruments TLV320AIC32x4
4  *
5  * Copyright 2019 Annaliese McDermond
6  *
7  * Author: Annaliese McDermond <nh6z@nh6z.net>
8  */
9 
10 #include <linux/clk-provider.h>
11 #include <linux/clkdev.h>
12 #include <linux/regmap.h>
13 #include <linux/device.h>
14 
15 #include "tlv320aic32x4.h"
16 
17 #define to_clk_aic32x4(_hw) container_of(_hw, struct clk_aic32x4, hw)
18 struct clk_aic32x4 {
19 	struct clk_hw hw;
20 	struct device *dev;
21 	struct regmap *regmap;
22 	unsigned int reg;
23 };
24 
25 /*
26  * struct clk_aic32x4_pll_muldiv - Multiplier/divider settings
27  * @p:		Divider
28  * @r:		first multiplier
29  * @j:		integer part of second multiplier
30  * @d:		decimal part of second multiplier
31  */
32 struct clk_aic32x4_pll_muldiv {
33 	u8 p;
34 	u16 r;
35 	u8 j;
36 	u16 d;
37 };
38 
39 struct aic32x4_clkdesc {
40 	const char *name;
41 	const char * const *parent_names;
42 	unsigned int num_parents;
43 	const struct clk_ops *ops;
44 	unsigned int reg;
45 };
46 
47 static int clk_aic32x4_pll_prepare(struct clk_hw *hw)
48 {
49 	struct clk_aic32x4 *pll = to_clk_aic32x4(hw);
50 
51 	return regmap_update_bits(pll->regmap, AIC32X4_PLLPR,
52 				AIC32X4_PLLEN, AIC32X4_PLLEN);
53 }
54 
55 static void clk_aic32x4_pll_unprepare(struct clk_hw *hw)
56 {
57 	struct clk_aic32x4 *pll = to_clk_aic32x4(hw);
58 
59 	regmap_update_bits(pll->regmap, AIC32X4_PLLPR,
60 				AIC32X4_PLLEN, 0);
61 }
62 
63 static int clk_aic32x4_pll_is_prepared(struct clk_hw *hw)
64 {
65 	struct clk_aic32x4 *pll = to_clk_aic32x4(hw);
66 
67 	unsigned int val;
68 	int ret;
69 
70 	ret = regmap_read(pll->regmap, AIC32X4_PLLPR, &val);
71 	if (ret < 0)
72 		return ret;
73 
74 	return !!(val & AIC32X4_PLLEN);
75 }
76 
77 static int clk_aic32x4_pll_get_muldiv(struct clk_aic32x4 *pll,
78 			struct clk_aic32x4_pll_muldiv *settings)
79 {
80 	/*	Change to use regmap_bulk_read? */
81 	unsigned int val;
82 	int ret;
83 
84 	ret = regmap_read(pll->regmap, AIC32X4_PLLPR, &val);
85 	if (ret < 0)
86 		return ret;
87 	settings->r = val & AIC32X4_PLL_R_MASK;
88 	settings->p = (val & AIC32X4_PLL_P_MASK) >> AIC32X4_PLL_P_SHIFT;
89 
90 	ret = regmap_read(pll->regmap, AIC32X4_PLLJ, &val);
91 	if (ret < 0)
92 		return ret;
93 	settings->j = val;
94 
95 	ret = regmap_read(pll->regmap, AIC32X4_PLLDMSB, &val);
96 	if (ret < 0)
97 		return ret;
98 	settings->d = val << 8;
99 
100 	ret = regmap_read(pll->regmap, AIC32X4_PLLDLSB,	 &val);
101 	if (ret < 0)
102 		return ret;
103 	settings->d |= val;
104 
105 	return 0;
106 }
107 
108 static int clk_aic32x4_pll_set_muldiv(struct clk_aic32x4 *pll,
109 			struct clk_aic32x4_pll_muldiv *settings)
110 {
111 	int ret;
112 	/*	Change to use regmap_bulk_write for some if not all? */
113 
114 	ret = regmap_update_bits(pll->regmap, AIC32X4_PLLPR,
115 				AIC32X4_PLL_R_MASK, settings->r);
116 	if (ret < 0)
117 		return ret;
118 
119 	ret = regmap_update_bits(pll->regmap, AIC32X4_PLLPR,
120 				AIC32X4_PLL_P_MASK,
121 				settings->p << AIC32X4_PLL_P_SHIFT);
122 	if (ret < 0)
123 		return ret;
124 
125 	ret = regmap_write(pll->regmap, AIC32X4_PLLJ, settings->j);
126 	if (ret < 0)
127 		return ret;
128 
129 	ret = regmap_write(pll->regmap, AIC32X4_PLLDMSB, (settings->d >> 8));
130 	if (ret < 0)
131 		return ret;
132 	ret = regmap_write(pll->regmap, AIC32X4_PLLDLSB, (settings->d & 0xff));
133 	if (ret < 0)
134 		return ret;
135 
136 	return 0;
137 }
138 
139 static unsigned long clk_aic32x4_pll_calc_rate(
140 			struct clk_aic32x4_pll_muldiv *settings,
141 			unsigned long parent_rate)
142 {
143 	u64 rate;
144 	/*
145 	 * We scale j by 10000 to account for the decimal part of P and divide
146 	 * it back out later.
147 	 */
148 	rate = (u64) parent_rate * settings->r *
149 				((settings->j * 10000) + settings->d);
150 
151 	return (unsigned long) DIV_ROUND_UP_ULL(rate, settings->p * 10000);
152 }
153 
154 static int clk_aic32x4_pll_calc_muldiv(struct clk_aic32x4_pll_muldiv *settings,
155 			unsigned long rate, unsigned long parent_rate)
156 {
157 	u64 multiplier;
158 
159 	settings->p = parent_rate / AIC32X4_MAX_PLL_CLKIN + 1;
160 	if (settings->p > 8)
161 		return -1;
162 
163 	/*
164 	 * We scale this figure by 10000 so that we can get the decimal part
165 	 * of the multiplier.	This is because we can't do floating point
166 	 * math in the kernel.
167 	 */
168 	multiplier = (u64) rate * settings->p * 10000;
169 	do_div(multiplier, parent_rate);
170 
171 	/*
172 	 * J can't be over 64, so R can scale this.
173 	 * R can't be greater than 4.
174 	 */
175 	settings->r = ((u32) multiplier / 640000) + 1;
176 	if (settings->r > 4)
177 		return -1;
178 	do_div(multiplier, settings->r);
179 
180 	/*
181 	 * J can't be < 1.
182 	 */
183 	if (multiplier < 10000)
184 		return -1;
185 
186 	/* Figure out the integer part, J, and the fractional part, D. */
187 	settings->j = (u32) multiplier / 10000;
188 	settings->d = (u32) multiplier % 10000;
189 
190 	return 0;
191 }
192 
193 static unsigned long clk_aic32x4_pll_recalc_rate(struct clk_hw *hw,
194 			unsigned long parent_rate)
195 {
196 	struct clk_aic32x4 *pll = to_clk_aic32x4(hw);
197 	struct clk_aic32x4_pll_muldiv settings;
198 	int ret;
199 
200 	ret =  clk_aic32x4_pll_get_muldiv(pll, &settings);
201 	if (ret < 0)
202 		return 0;
203 
204 	return clk_aic32x4_pll_calc_rate(&settings, parent_rate);
205 }
206 
207 static int clk_aic32x4_pll_determine_rate(struct clk_hw *hw,
208 					  struct clk_rate_request *req)
209 {
210 	struct clk_aic32x4_pll_muldiv settings;
211 	int ret;
212 
213 	ret = clk_aic32x4_pll_calc_muldiv(&settings, req->rate, req->best_parent_rate);
214 	if (ret < 0)
215 		return -EINVAL;
216 
217 	req->rate = clk_aic32x4_pll_calc_rate(&settings, req->best_parent_rate);
218 
219 	return 0;
220 }
221 
222 static int clk_aic32x4_pll_set_rate(struct clk_hw *hw,
223 			unsigned long rate,
224 			unsigned long parent_rate)
225 {
226 	struct clk_aic32x4 *pll = to_clk_aic32x4(hw);
227 	struct clk_aic32x4_pll_muldiv settings;
228 	int ret;
229 
230 	ret = clk_aic32x4_pll_calc_muldiv(&settings, rate, parent_rate);
231 	if (ret < 0)
232 		return -EINVAL;
233 
234 	ret = clk_aic32x4_pll_set_muldiv(pll, &settings);
235 	if (ret)
236 		return ret;
237 
238 	/* 10ms is the delay to wait before the clocks are stable */
239 	msleep(10);
240 
241 	return 0;
242 }
243 
244 static int clk_aic32x4_pll_set_parent(struct clk_hw *hw, u8 index)
245 {
246 	struct clk_aic32x4 *pll = to_clk_aic32x4(hw);
247 
248 	return regmap_update_bits(pll->regmap,
249 				AIC32X4_CLKMUX,
250 				AIC32X4_PLL_CLKIN_MASK,
251 				index << AIC32X4_PLL_CLKIN_SHIFT);
252 }
253 
254 static u8 clk_aic32x4_pll_get_parent(struct clk_hw *hw)
255 {
256 	struct clk_aic32x4 *pll = to_clk_aic32x4(hw);
257 	unsigned int val;
258 
259 	regmap_read(pll->regmap, AIC32X4_PLLPR, &val);
260 
261 	return (val & AIC32X4_PLL_CLKIN_MASK) >> AIC32X4_PLL_CLKIN_SHIFT;
262 }
263 
264 
265 static const struct clk_ops aic32x4_pll_ops = {
266 	.prepare = clk_aic32x4_pll_prepare,
267 	.unprepare = clk_aic32x4_pll_unprepare,
268 	.is_prepared = clk_aic32x4_pll_is_prepared,
269 	.recalc_rate = clk_aic32x4_pll_recalc_rate,
270 	.determine_rate = clk_aic32x4_pll_determine_rate,
271 	.set_rate = clk_aic32x4_pll_set_rate,
272 	.set_parent = clk_aic32x4_pll_set_parent,
273 	.get_parent = clk_aic32x4_pll_get_parent,
274 };
275 
276 static int clk_aic32x4_codec_clkin_set_parent(struct clk_hw *hw, u8 index)
277 {
278 	struct clk_aic32x4 *mux = to_clk_aic32x4(hw);
279 
280 	return regmap_update_bits(mux->regmap,
281 		AIC32X4_CLKMUX,
282 		AIC32X4_CODEC_CLKIN_MASK, index << AIC32X4_CODEC_CLKIN_SHIFT);
283 }
284 
285 static u8 clk_aic32x4_codec_clkin_get_parent(struct clk_hw *hw)
286 {
287 	struct clk_aic32x4 *mux = to_clk_aic32x4(hw);
288 	unsigned int val;
289 
290 	regmap_read(mux->regmap, AIC32X4_CLKMUX, &val);
291 
292 	return (val & AIC32X4_CODEC_CLKIN_MASK) >> AIC32X4_CODEC_CLKIN_SHIFT;
293 }
294 
295 static const struct clk_ops aic32x4_codec_clkin_ops = {
296 	.determine_rate = clk_hw_determine_rate_no_reparent,
297 	.set_parent = clk_aic32x4_codec_clkin_set_parent,
298 	.get_parent = clk_aic32x4_codec_clkin_get_parent,
299 };
300 
301 static int clk_aic32x4_div_prepare(struct clk_hw *hw)
302 {
303 	struct clk_aic32x4 *div = to_clk_aic32x4(hw);
304 
305 	return regmap_update_bits(div->regmap, div->reg,
306 				AIC32X4_DIVEN, AIC32X4_DIVEN);
307 }
308 
309 static void clk_aic32x4_div_unprepare(struct clk_hw *hw)
310 {
311 	struct clk_aic32x4 *div = to_clk_aic32x4(hw);
312 
313 	regmap_update_bits(div->regmap, div->reg,
314 			AIC32X4_DIVEN, 0);
315 }
316 
317 static int clk_aic32x4_div_set_rate(struct clk_hw *hw, unsigned long rate,
318 				unsigned long parent_rate)
319 {
320 	struct clk_aic32x4 *div = to_clk_aic32x4(hw);
321 	u8 divisor;
322 
323 	divisor = DIV_ROUND_UP(parent_rate, rate);
324 	if (divisor > AIC32X4_DIV_MAX)
325 		return -EINVAL;
326 
327 	return regmap_update_bits(div->regmap, div->reg,
328 				AIC32X4_DIV_MASK, divisor);
329 }
330 
331 static int clk_aic32x4_div_determine_rate(struct clk_hw *hw,
332 					  struct clk_rate_request *req)
333 {
334 	unsigned long divisor;
335 
336 	divisor = DIV_ROUND_UP(req->best_parent_rate, req->rate);
337 	if (divisor > AIC32X4_DIV_MAX)
338 		return -EINVAL;
339 
340 	req->rate = DIV_ROUND_UP(req->best_parent_rate, divisor);
341 	return 0;
342 }
343 
344 static unsigned long clk_aic32x4_div_recalc_rate(struct clk_hw *hw,
345 						unsigned long parent_rate)
346 {
347 	struct clk_aic32x4 *div = to_clk_aic32x4(hw);
348 	unsigned int val;
349 	int err;
350 
351 	err = regmap_read(div->regmap, div->reg, &val);
352 	if (err)
353 		return 0;
354 
355 	val &= AIC32X4_DIV_MASK;
356 	if (!val)
357 		val = AIC32X4_DIV_MAX;
358 
359 	return DIV_ROUND_UP(parent_rate, val);
360 }
361 
362 static const struct clk_ops aic32x4_div_ops = {
363 	.prepare = clk_aic32x4_div_prepare,
364 	.unprepare = clk_aic32x4_div_unprepare,
365 	.set_rate = clk_aic32x4_div_set_rate,
366 	.determine_rate = clk_aic32x4_div_determine_rate,
367 	.recalc_rate = clk_aic32x4_div_recalc_rate,
368 };
369 
370 static int clk_aic32x4_bdiv_set_parent(struct clk_hw *hw, u8 index)
371 {
372 	struct clk_aic32x4 *mux = to_clk_aic32x4(hw);
373 
374 	return regmap_update_bits(mux->regmap, AIC32X4_IFACE3,
375 				AIC32X4_BDIVCLK_MASK, index);
376 }
377 
378 static u8 clk_aic32x4_bdiv_get_parent(struct clk_hw *hw)
379 {
380 	struct clk_aic32x4 *mux = to_clk_aic32x4(hw);
381 	unsigned int val;
382 
383 	regmap_read(mux->regmap, AIC32X4_IFACE3, &val);
384 
385 	return val & AIC32X4_BDIVCLK_MASK;
386 }
387 
388 static const struct clk_ops aic32x4_bdiv_ops = {
389 	.prepare = clk_aic32x4_div_prepare,
390 	.unprepare = clk_aic32x4_div_unprepare,
391 	.set_parent = clk_aic32x4_bdiv_set_parent,
392 	.get_parent = clk_aic32x4_bdiv_get_parent,
393 	.set_rate = clk_aic32x4_div_set_rate,
394 	.determine_rate = clk_aic32x4_div_determine_rate,
395 	.recalc_rate = clk_aic32x4_div_recalc_rate,
396 };
397 
398 static struct aic32x4_clkdesc aic32x4_clkdesc_array[] = {
399 	{
400 		.name = "pll",
401 		.parent_names =
402 			(const char* []) { "mclk", "bclk", "gpio", "din" },
403 		.num_parents = 4,
404 		.ops = &aic32x4_pll_ops,
405 		.reg = 0,
406 	},
407 	{
408 		.name = "codec_clkin",
409 		.parent_names =
410 			(const char *[]) { "mclk", "bclk", "gpio", "pll" },
411 		.num_parents = 4,
412 		.ops = &aic32x4_codec_clkin_ops,
413 		.reg = 0,
414 	},
415 	{
416 		.name = "ndac",
417 		.parent_names = (const char * []) { "codec_clkin" },
418 		.num_parents = 1,
419 		.ops = &aic32x4_div_ops,
420 		.reg = AIC32X4_NDAC,
421 	},
422 	{
423 		.name = "mdac",
424 		.parent_names = (const char * []) { "ndac" },
425 		.num_parents = 1,
426 		.ops = &aic32x4_div_ops,
427 		.reg = AIC32X4_MDAC,
428 	},
429 	{
430 		.name = "nadc",
431 		.parent_names = (const char * []) { "codec_clkin" },
432 		.num_parents = 1,
433 		.ops = &aic32x4_div_ops,
434 		.reg = AIC32X4_NADC,
435 	},
436 	{
437 		.name = "madc",
438 		.parent_names = (const char * []) { "nadc" },
439 		.num_parents = 1,
440 		.ops = &aic32x4_div_ops,
441 		.reg = AIC32X4_MADC,
442 	},
443 	{
444 		.name = "bdiv",
445 		.parent_names =
446 			(const char *[]) { "ndac", "mdac", "nadc", "madc" },
447 		.num_parents = 4,
448 		.ops = &aic32x4_bdiv_ops,
449 		.reg = AIC32X4_BCLKN,
450 	},
451 };
452 
453 static struct clk *aic32x4_register_clk(struct device *dev,
454 			struct aic32x4_clkdesc *desc)
455 {
456 	struct clk_init_data init;
457 	struct clk_aic32x4 *priv;
458 	const char *devname = dev_name(dev);
459 
460 	init.ops = desc->ops;
461 	init.name = desc->name;
462 	init.parent_names = desc->parent_names;
463 	init.num_parents = desc->num_parents;
464 	init.flags = 0;
465 
466 	priv = devm_kzalloc(dev, sizeof(struct clk_aic32x4), GFP_KERNEL);
467 	if (priv == NULL)
468 		return (struct clk *) -ENOMEM;
469 
470 	priv->dev = dev;
471 	priv->hw.init = &init;
472 	priv->regmap = dev_get_regmap(dev, NULL);
473 	priv->reg = desc->reg;
474 
475 	clk_hw_register_clkdev(&priv->hw, desc->name, devname);
476 	return devm_clk_register(dev, &priv->hw);
477 }
478 
479 int aic32x4_register_clocks(struct device *dev, const char *mclk_name)
480 {
481 	int i;
482 
483 	/*
484 	 * These lines are here to preserve the current functionality of
485 	 * the driver with regard to the DT.  These should eventually be set
486 	 * by DT nodes so that the connections can be set up in configuration
487 	 * rather than code.
488 	 */
489 	aic32x4_clkdesc_array[0].parent_names =
490 			(const char* []) { mclk_name, "bclk", "gpio", "din" };
491 	aic32x4_clkdesc_array[1].parent_names =
492 			(const char *[]) { mclk_name, "bclk", "gpio", "pll" };
493 
494 	for (i = 0; i < ARRAY_SIZE(aic32x4_clkdesc_array); ++i)
495 		aic32x4_register_clk(dev, &aic32x4_clkdesc_array[i]);
496 
497 	return 0;
498 }
499 EXPORT_SYMBOL_GPL(aic32x4_register_clocks);
500