Commit | Line | Data |
---|---|---|
64dfbe24 KM |
1 | /* |
2 | * CS2000 -- CIRRUS LOGIC Fractional-N Clock Synthesizer & Clock Multiplier | |
3 | * | |
4 | * Copyright (C) 2015 Renesas Electronics Corporation | |
5 | * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License version 2 as | |
9 | * published by the Free Software Foundation. | |
10 | */ | |
11 | #include <linux/clk-provider.h> | |
12 | #include <linux/delay.h> | |
13 | #include <linux/clk.h> | |
14 | #include <linux/i2c.h> | |
15 | #include <linux/of_device.h> | |
16 | #include <linux/module.h> | |
17 | ||
18 | #define CH_MAX 4 | |
19 | #define RATIO_REG_SIZE 4 | |
20 | ||
21 | #define DEVICE_ID 0x1 | |
22 | #define DEVICE_CTRL 0x2 | |
23 | #define DEVICE_CFG1 0x3 | |
24 | #define DEVICE_CFG2 0x4 | |
25 | #define GLOBAL_CFG 0x5 | |
26 | #define Ratio_Add(x, nth) (6 + (x * 4) + (nth)) | |
27 | #define Ratio_Val(x, nth) ((x >> (24 - (8 * nth))) & 0xFF) | |
28 | #define Val_Ratio(x, nth) ((x & 0xFF) << (24 - (8 * nth))) | |
29 | #define FUNC_CFG1 0x16 | |
30 | #define FUNC_CFG2 0x17 | |
31 | ||
32 | /* DEVICE_ID */ | |
33 | #define REVISION_MASK (0x7) | |
34 | #define REVISION_B2_B3 (0x4) | |
35 | #define REVISION_C1 (0x6) | |
36 | ||
37 | /* DEVICE_CTRL */ | |
38 | #define PLL_UNLOCK (1 << 7) | |
1f9dfd7a KM |
39 | #define AUXOUTDIS (1 << 1) |
40 | #define CLKOUTDIS (1 << 0) | |
64dfbe24 KM |
41 | |
42 | /* DEVICE_CFG1 */ | |
43 | #define RSEL(x) (((x) & 0x3) << 3) | |
44 | #define RSEL_MASK RSEL(0x3) | |
45 | #define ENDEV1 (0x1) | |
46 | ||
1f9dfd7a KM |
47 | /* DEVICE_CFG2 */ |
48 | #define AUTORMOD (1 << 3) | |
49 | #define LOCKCLK(x) (((x) & 0x3) << 1) | |
50 | #define LOCKCLK_MASK LOCKCLK(0x3) | |
b295a015 KM |
51 | #define FRACNSRC_MASK (1 << 0) |
52 | #define FRACNSRC_STATIC (0 << 0) | |
53 | #define FRACNSRC_DYNAMIC (1 << 1) | |
1f9dfd7a | 54 | |
64dfbe24 KM |
55 | /* GLOBAL_CFG */ |
56 | #define ENDEV2 (0x1) | |
57 | ||
1f9dfd7a | 58 | /* FUNC_CFG1 */ |
d127967a | 59 | #define CLKSKIPEN (1 << 7) |
1f9dfd7a KM |
60 | #define REFCLKDIV(x) (((x) & 0x3) << 3) |
61 | #define REFCLKDIV_MASK REFCLKDIV(0x3) | |
62 | ||
b3da896e KM |
63 | /* FUNC_CFG2 */ |
64 | #define LFRATIO_MASK (1 << 3) | |
65 | #define LFRATIO_20_12 (0 << 3) | |
66 | #define LFRATIO_12_20 (1 << 3) | |
67 | ||
64dfbe24 KM |
68 | #define CH_SIZE_ERR(ch) ((ch < 0) || (ch >= CH_MAX)) |
69 | #define hw_to_priv(_hw) container_of(_hw, struct cs2000_priv, hw) | |
70 | #define priv_to_client(priv) (priv->client) | |
71 | #define priv_to_dev(priv) (&(priv_to_client(priv)->dev)) | |
72 | ||
73 | #define CLK_IN 0 | |
74 | #define REF_CLK 1 | |
75 | #define CLK_MAX 2 | |
76 | ||
77 | struct cs2000_priv { | |
78 | struct clk_hw hw; | |
79 | struct i2c_client *client; | |
80 | struct clk *clk_in; | |
81 | struct clk *ref_clk; | |
c567fb37 KN |
82 | |
83 | /* suspend/resume */ | |
84 | unsigned long saved_rate; | |
85 | unsigned long saved_parent_rate; | |
64dfbe24 KM |
86 | }; |
87 | ||
88 | static const struct of_device_id cs2000_of_match[] = { | |
89 | { .compatible = "cirrus,cs2000-cp", }, | |
90 | {}, | |
91 | }; | |
92 | MODULE_DEVICE_TABLE(of, cs2000_of_match); | |
93 | ||
94 | static const struct i2c_device_id cs2000_id[] = { | |
95 | { "cs2000-cp", }, | |
96 | {} | |
97 | }; | |
98 | MODULE_DEVICE_TABLE(i2c, cs2000_id); | |
99 | ||
100 | #define cs2000_read(priv, addr) \ | |
101 | i2c_smbus_read_byte_data(priv_to_client(priv), addr) | |
102 | #define cs2000_write(priv, addr, val) \ | |
103 | i2c_smbus_write_byte_data(priv_to_client(priv), addr, val) | |
104 | ||
105 | static int cs2000_bset(struct cs2000_priv *priv, u8 addr, u8 mask, u8 val) | |
106 | { | |
107 | s32 data; | |
108 | ||
109 | data = cs2000_read(priv, addr); | |
110 | if (data < 0) | |
111 | return data; | |
112 | ||
113 | data &= ~mask; | |
114 | data |= (val & mask); | |
115 | ||
116 | return cs2000_write(priv, addr, data); | |
117 | } | |
118 | ||
119 | static int cs2000_enable_dev_config(struct cs2000_priv *priv, bool enable) | |
120 | { | |
121 | int ret; | |
122 | ||
123 | ret = cs2000_bset(priv, DEVICE_CFG1, ENDEV1, | |
124 | enable ? ENDEV1 : 0); | |
125 | if (ret < 0) | |
126 | return ret; | |
127 | ||
128 | ret = cs2000_bset(priv, GLOBAL_CFG, ENDEV2, | |
129 | enable ? ENDEV2 : 0); | |
130 | if (ret < 0) | |
131 | return ret; | |
132 | ||
d127967a KM |
133 | ret = cs2000_bset(priv, FUNC_CFG1, CLKSKIPEN, |
134 | enable ? CLKSKIPEN : 0); | |
135 | if (ret < 0) | |
136 | return ret; | |
137 | ||
b3da896e KM |
138 | /* FIXME: for Static ratio mode */ |
139 | ret = cs2000_bset(priv, FUNC_CFG2, LFRATIO_MASK, | |
140 | LFRATIO_12_20); | |
141 | if (ret < 0) | |
142 | return ret; | |
143 | ||
64dfbe24 KM |
144 | return 0; |
145 | } | |
146 | ||
147 | static int cs2000_clk_in_bound_rate(struct cs2000_priv *priv, | |
148 | u32 rate_in) | |
149 | { | |
150 | u32 val; | |
151 | ||
152 | if (rate_in >= 32000000 && rate_in < 56000000) | |
153 | val = 0x0; | |
154 | else if (rate_in >= 16000000 && rate_in < 28000000) | |
155 | val = 0x1; | |
156 | else if (rate_in >= 8000000 && rate_in < 14000000) | |
157 | val = 0x2; | |
158 | else | |
159 | return -EINVAL; | |
160 | ||
1f9dfd7a KM |
161 | return cs2000_bset(priv, FUNC_CFG1, |
162 | REFCLKDIV_MASK, | |
163 | REFCLKDIV(val)); | |
64dfbe24 KM |
164 | } |
165 | ||
166 | static int cs2000_wait_pll_lock(struct cs2000_priv *priv) | |
167 | { | |
168 | struct device *dev = priv_to_dev(priv); | |
169 | s32 val; | |
170 | unsigned int i; | |
171 | ||
172 | for (i = 0; i < 256; i++) { | |
173 | val = cs2000_read(priv, DEVICE_CTRL); | |
174 | if (val < 0) | |
175 | return val; | |
176 | if (!(val & PLL_UNLOCK)) | |
177 | return 0; | |
178 | udelay(1); | |
179 | } | |
180 | ||
181 | dev_err(dev, "pll lock failed\n"); | |
182 | ||
183 | return -ETIMEDOUT; | |
184 | } | |
185 | ||
186 | static int cs2000_clk_out_enable(struct cs2000_priv *priv, bool enable) | |
187 | { | |
188 | /* enable both AUX_OUT, CLK_OUT */ | |
1f9dfd7a KM |
189 | return cs2000_bset(priv, DEVICE_CTRL, |
190 | (AUXOUTDIS | CLKOUTDIS), | |
191 | enable ? 0 : | |
192 | (AUXOUTDIS | CLKOUTDIS)); | |
64dfbe24 KM |
193 | } |
194 | ||
195 | static u32 cs2000_rate_to_ratio(u32 rate_in, u32 rate_out) | |
196 | { | |
197 | u64 ratio; | |
198 | ||
199 | /* | |
200 | * ratio = rate_out / rate_in * 2^20 | |
201 | * | |
202 | * To avoid over flow, rate_out is u64. | |
203 | * The result should be u32. | |
204 | */ | |
205 | ratio = (u64)rate_out << 20; | |
206 | do_div(ratio, rate_in); | |
207 | ||
208 | return ratio; | |
209 | } | |
210 | ||
211 | static unsigned long cs2000_ratio_to_rate(u32 ratio, u32 rate_in) | |
212 | { | |
213 | u64 rate_out; | |
214 | ||
215 | /* | |
216 | * ratio = rate_out / rate_in * 2^20 | |
217 | * | |
218 | * To avoid over flow, rate_out is u64. | |
219 | * The result should be u32 or unsigned long. | |
220 | */ | |
221 | ||
222 | rate_out = (u64)ratio * rate_in; | |
223 | return rate_out >> 20; | |
224 | } | |
225 | ||
226 | static int cs2000_ratio_set(struct cs2000_priv *priv, | |
227 | int ch, u32 rate_in, u32 rate_out) | |
228 | { | |
229 | u32 val; | |
230 | unsigned int i; | |
231 | int ret; | |
232 | ||
233 | if (CH_SIZE_ERR(ch)) | |
234 | return -EINVAL; | |
235 | ||
236 | val = cs2000_rate_to_ratio(rate_in, rate_out); | |
237 | for (i = 0; i < RATIO_REG_SIZE; i++) { | |
238 | ret = cs2000_write(priv, | |
239 | Ratio_Add(ch, i), | |
240 | Ratio_Val(val, i)); | |
241 | if (ret < 0) | |
242 | return ret; | |
243 | } | |
244 | ||
245 | return 0; | |
246 | } | |
247 | ||
248 | static u32 cs2000_ratio_get(struct cs2000_priv *priv, int ch) | |
249 | { | |
250 | s32 tmp; | |
251 | u32 val; | |
252 | unsigned int i; | |
253 | ||
254 | val = 0; | |
255 | for (i = 0; i < RATIO_REG_SIZE; i++) { | |
256 | tmp = cs2000_read(priv, Ratio_Add(ch, i)); | |
257 | if (tmp < 0) | |
258 | return 0; | |
259 | ||
260 | val |= Val_Ratio(tmp, i); | |
261 | } | |
262 | ||
263 | return val; | |
264 | } | |
265 | ||
266 | static int cs2000_ratio_select(struct cs2000_priv *priv, int ch) | |
267 | { | |
268 | int ret; | |
269 | ||
270 | if (CH_SIZE_ERR(ch)) | |
271 | return -EINVAL; | |
272 | ||
273 | /* | |
274 | * FIXME | |
275 | * | |
276 | * this driver supports static ratio mode only at this point. | |
277 | */ | |
278 | ret = cs2000_bset(priv, DEVICE_CFG1, RSEL_MASK, RSEL(ch)); | |
279 | if (ret < 0) | |
280 | return ret; | |
281 | ||
1f9dfd7a | 282 | ret = cs2000_bset(priv, DEVICE_CFG2, |
b295a015 KM |
283 | (AUTORMOD | LOCKCLK_MASK | FRACNSRC_MASK), |
284 | (LOCKCLK(ch) | FRACNSRC_STATIC)); | |
64dfbe24 KM |
285 | if (ret < 0) |
286 | return ret; | |
287 | ||
288 | return 0; | |
289 | } | |
290 | ||
291 | static unsigned long cs2000_recalc_rate(struct clk_hw *hw, | |
292 | unsigned long parent_rate) | |
293 | { | |
294 | struct cs2000_priv *priv = hw_to_priv(hw); | |
295 | int ch = 0; /* it uses ch0 only at this point */ | |
296 | u32 ratio; | |
297 | ||
298 | ratio = cs2000_ratio_get(priv, ch); | |
299 | ||
300 | return cs2000_ratio_to_rate(ratio, parent_rate); | |
301 | } | |
302 | ||
303 | static long cs2000_round_rate(struct clk_hw *hw, unsigned long rate, | |
304 | unsigned long *parent_rate) | |
305 | { | |
306 | u32 ratio; | |
307 | ||
308 | ratio = cs2000_rate_to_ratio(*parent_rate, rate); | |
309 | ||
310 | return cs2000_ratio_to_rate(ratio, *parent_rate); | |
311 | } | |
312 | ||
313 | static int __cs2000_set_rate(struct cs2000_priv *priv, int ch, | |
314 | unsigned long rate, unsigned long parent_rate) | |
315 | ||
316 | { | |
317 | int ret; | |
318 | ||
319 | ret = cs2000_clk_in_bound_rate(priv, parent_rate); | |
320 | if (ret < 0) | |
321 | return ret; | |
322 | ||
323 | ret = cs2000_ratio_set(priv, ch, parent_rate, rate); | |
324 | if (ret < 0) | |
325 | return ret; | |
326 | ||
327 | ret = cs2000_ratio_select(priv, ch); | |
328 | if (ret < 0) | |
329 | return ret; | |
330 | ||
c567fb37 KN |
331 | priv->saved_rate = rate; |
332 | priv->saved_parent_rate = parent_rate; | |
333 | ||
64dfbe24 KM |
334 | return 0; |
335 | } | |
336 | ||
337 | static int cs2000_set_rate(struct clk_hw *hw, | |
338 | unsigned long rate, unsigned long parent_rate) | |
339 | { | |
340 | struct cs2000_priv *priv = hw_to_priv(hw); | |
341 | int ch = 0; /* it uses ch0 only at this point */ | |
342 | ||
343 | return __cs2000_set_rate(priv, ch, rate, parent_rate); | |
344 | } | |
345 | ||
e001525c GI |
346 | static int cs2000_set_saved_rate(struct cs2000_priv *priv) |
347 | { | |
348 | int ch = 0; /* it uses ch0 only at this point */ | |
349 | ||
350 | return __cs2000_set_rate(priv, ch, | |
351 | priv->saved_rate, | |
352 | priv->saved_parent_rate); | |
353 | } | |
354 | ||
64dfbe24 KM |
355 | static int cs2000_enable(struct clk_hw *hw) |
356 | { | |
357 | struct cs2000_priv *priv = hw_to_priv(hw); | |
358 | int ret; | |
359 | ||
360 | ret = cs2000_enable_dev_config(priv, true); | |
361 | if (ret < 0) | |
362 | return ret; | |
363 | ||
364 | ret = cs2000_clk_out_enable(priv, true); | |
365 | if (ret < 0) | |
366 | return ret; | |
367 | ||
368 | ret = cs2000_wait_pll_lock(priv); | |
369 | if (ret < 0) | |
370 | return ret; | |
371 | ||
372 | return ret; | |
373 | } | |
374 | ||
375 | static void cs2000_disable(struct clk_hw *hw) | |
376 | { | |
377 | struct cs2000_priv *priv = hw_to_priv(hw); | |
378 | ||
379 | cs2000_enable_dev_config(priv, false); | |
380 | ||
381 | cs2000_clk_out_enable(priv, false); | |
382 | } | |
383 | ||
384 | static u8 cs2000_get_parent(struct clk_hw *hw) | |
385 | { | |
386 | /* always return REF_CLK */ | |
387 | return REF_CLK; | |
388 | } | |
389 | ||
390 | static const struct clk_ops cs2000_ops = { | |
391 | .get_parent = cs2000_get_parent, | |
392 | .recalc_rate = cs2000_recalc_rate, | |
393 | .round_rate = cs2000_round_rate, | |
394 | .set_rate = cs2000_set_rate, | |
395 | .prepare = cs2000_enable, | |
396 | .unprepare = cs2000_disable, | |
397 | }; | |
398 | ||
399 | static int cs2000_clk_get(struct cs2000_priv *priv) | |
400 | { | |
83dd720d | 401 | struct device *dev = priv_to_dev(priv); |
64dfbe24 KM |
402 | struct clk *clk_in, *ref_clk; |
403 | ||
404 | clk_in = devm_clk_get(dev, "clk_in"); | |
405 | /* not yet provided */ | |
406 | if (IS_ERR(clk_in)) | |
407 | return -EPROBE_DEFER; | |
408 | ||
409 | ref_clk = devm_clk_get(dev, "ref_clk"); | |
410 | /* not yet provided */ | |
411 | if (IS_ERR(ref_clk)) | |
412 | return -EPROBE_DEFER; | |
413 | ||
414 | priv->clk_in = clk_in; | |
415 | priv->ref_clk = ref_clk; | |
416 | ||
417 | return 0; | |
418 | } | |
419 | ||
420 | static int cs2000_clk_register(struct cs2000_priv *priv) | |
421 | { | |
422 | struct device *dev = priv_to_dev(priv); | |
423 | struct device_node *np = dev->of_node; | |
424 | struct clk_init_data init; | |
425 | const char *name = np->name; | |
64dfbe24 KM |
426 | static const char *parent_names[CLK_MAX]; |
427 | int ch = 0; /* it uses ch0 only at this point */ | |
428 | int rate; | |
429 | int ret; | |
430 | ||
431 | of_property_read_string(np, "clock-output-names", &name); | |
432 | ||
433 | /* | |
434 | * set default rate as 1/1. | |
435 | * otherwise .set_rate which setup ratio | |
436 | * is never called if user requests 1/1 rate | |
437 | */ | |
438 | rate = clk_get_rate(priv->ref_clk); | |
439 | ret = __cs2000_set_rate(priv, ch, rate, rate); | |
440 | if (ret < 0) | |
441 | return ret; | |
442 | ||
443 | parent_names[CLK_IN] = __clk_get_name(priv->clk_in); | |
444 | parent_names[REF_CLK] = __clk_get_name(priv->ref_clk); | |
445 | ||
446 | init.name = name; | |
447 | init.ops = &cs2000_ops; | |
448 | init.flags = CLK_SET_RATE_GATE; | |
449 | init.parent_names = parent_names; | |
450 | init.num_parents = ARRAY_SIZE(parent_names); | |
451 | ||
452 | priv->hw.init = &init; | |
453 | ||
2ceb3c7a SB |
454 | ret = clk_hw_register(dev, &priv->hw); |
455 | if (ret) | |
456 | return ret; | |
64dfbe24 | 457 | |
2ceb3c7a | 458 | ret = of_clk_add_hw_provider(np, of_clk_hw_simple_get, &priv->hw); |
64dfbe24 | 459 | if (ret < 0) { |
2ceb3c7a | 460 | clk_hw_unregister(&priv->hw); |
64dfbe24 KM |
461 | return ret; |
462 | } | |
463 | ||
64dfbe24 KM |
464 | return 0; |
465 | } | |
466 | ||
467 | static int cs2000_version_print(struct cs2000_priv *priv) | |
468 | { | |
83dd720d | 469 | struct device *dev = priv_to_dev(priv); |
64dfbe24 KM |
470 | s32 val; |
471 | const char *revision; | |
472 | ||
473 | val = cs2000_read(priv, DEVICE_ID); | |
474 | if (val < 0) | |
475 | return val; | |
476 | ||
477 | /* CS2000 should be 0x0 */ | |
478 | if (val >> 3) | |
479 | return -EIO; | |
480 | ||
481 | switch (val & REVISION_MASK) { | |
482 | case REVISION_B2_B3: | |
483 | revision = "B2 / B3"; | |
484 | break; | |
485 | case REVISION_C1: | |
486 | revision = "C1"; | |
487 | break; | |
488 | default: | |
489 | return -EIO; | |
490 | } | |
491 | ||
492 | dev_info(dev, "revision - %s\n", revision); | |
493 | ||
494 | return 0; | |
495 | } | |
496 | ||
497 | static int cs2000_remove(struct i2c_client *client) | |
498 | { | |
499 | struct cs2000_priv *priv = i2c_get_clientdata(client); | |
83dd720d | 500 | struct device *dev = priv_to_dev(priv); |
64dfbe24 KM |
501 | struct device_node *np = dev->of_node; |
502 | ||
503 | of_clk_del_provider(np); | |
504 | ||
2ceb3c7a | 505 | clk_hw_unregister(&priv->hw); |
64dfbe24 KM |
506 | |
507 | return 0; | |
508 | } | |
509 | ||
510 | static int cs2000_probe(struct i2c_client *client, | |
511 | const struct i2c_device_id *id) | |
512 | { | |
513 | struct cs2000_priv *priv; | |
514 | struct device *dev = &client->dev; | |
515 | int ret; | |
516 | ||
517 | priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); | |
518 | if (!priv) | |
519 | return -ENOMEM; | |
520 | ||
521 | priv->client = client; | |
522 | i2c_set_clientdata(client, priv); | |
523 | ||
524 | ret = cs2000_clk_get(priv); | |
525 | if (ret < 0) | |
526 | return ret; | |
527 | ||
528 | ret = cs2000_clk_register(priv); | |
529 | if (ret < 0) | |
530 | return ret; | |
531 | ||
532 | ret = cs2000_version_print(priv); | |
533 | if (ret < 0) | |
534 | goto probe_err; | |
535 | ||
536 | return 0; | |
537 | ||
538 | probe_err: | |
539 | cs2000_remove(client); | |
540 | ||
541 | return ret; | |
542 | } | |
543 | ||
c567fb37 KN |
544 | static int cs2000_resume(struct device *dev) |
545 | { | |
546 | struct cs2000_priv *priv = dev_get_drvdata(dev); | |
c567fb37 | 547 | |
e001525c | 548 | return cs2000_set_saved_rate(priv); |
c567fb37 KN |
549 | } |
550 | ||
551 | static const struct dev_pm_ops cs2000_pm_ops = { | |
552 | .resume_early = cs2000_resume, | |
553 | }; | |
554 | ||
64dfbe24 KM |
555 | static struct i2c_driver cs2000_driver = { |
556 | .driver = { | |
557 | .name = "cs2000-cp", | |
c567fb37 | 558 | .pm = &cs2000_pm_ops, |
64dfbe24 KM |
559 | .of_match_table = cs2000_of_match, |
560 | }, | |
561 | .probe = cs2000_probe, | |
562 | .remove = cs2000_remove, | |
563 | .id_table = cs2000_id, | |
564 | }; | |
565 | ||
566 | module_i2c_driver(cs2000_driver); | |
567 | ||
568 | MODULE_DESCRIPTION("CS2000-CP driver"); | |
569 | MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>"); | |
570 | MODULE_LICENSE("GPL v2"); |