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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
33#define REVISION_MASK (0x7)
34#define REVISION_B2_B3 (0x4)
35#define REVISION_C1 (0x6)
36
37
38#define PLL_UNLOCK (1 << 7)
39#define AUXOUTDIS (1 << 1)
40#define CLKOUTDIS (1 << 0)
41
42
43#define RSEL(x) (((x) & 0x3) << 3)
44#define RSEL_MASK RSEL(0x3)
45#define ENDEV1 (0x1)
46
47
48#define AUTORMOD (1 << 3)
49#define LOCKCLK(x) (((x) & 0x3) << 1)
50#define LOCKCLK_MASK LOCKCLK(0x3)
51#define FRACNSRC_MASK (1 << 0)
52#define FRACNSRC_STATIC (0 << 0)
53#define FRACNSRC_DYNAMIC (1 << 1)
54
55
56#define ENDEV2 (0x1)
57
58
59#define CLKSKIPEN (1 << 7)
60#define REFCLKDIV(x) (((x) & 0x3) << 3)
61#define REFCLKDIV_MASK REFCLKDIV(0x3)
62
63
64#define LFRATIO_MASK (1 << 3)
65#define LFRATIO_20_12 (0 << 3)
66#define LFRATIO_12_20 (1 << 3)
67
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
77struct cs2000_priv {
78 struct clk_hw hw;
79 struct i2c_client *client;
80 struct clk *clk_in;
81 struct clk *ref_clk;
82
83
84 unsigned long saved_rate;
85 unsigned long saved_parent_rate;
86};
87
88static const struct of_device_id cs2000_of_match[] = {
89 { .compatible = "cirrus,cs2000-cp", },
90 {},
91};
92MODULE_DEVICE_TABLE(of, cs2000_of_match);
93
94static const struct i2c_device_id cs2000_id[] = {
95 { "cs2000-cp", },
96 {}
97};
98MODULE_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
105static 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
119static 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
133 ret = cs2000_bset(priv, FUNC_CFG1, CLKSKIPEN,
134 enable ? CLKSKIPEN : 0);
135 if (ret < 0)
136 return ret;
137
138
139 ret = cs2000_bset(priv, FUNC_CFG2, LFRATIO_MASK,
140 LFRATIO_12_20);
141 if (ret < 0)
142 return ret;
143
144 return 0;
145}
146
147static 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
161 return cs2000_bset(priv, FUNC_CFG1,
162 REFCLKDIV_MASK,
163 REFCLKDIV(val));
164}
165
166static 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
186static int cs2000_clk_out_enable(struct cs2000_priv *priv, bool enable)
187{
188
189 return cs2000_bset(priv, DEVICE_CTRL,
190 (AUXOUTDIS | CLKOUTDIS),
191 enable ? 0 :
192 (AUXOUTDIS | CLKOUTDIS));
193}
194
195static u32 cs2000_rate_to_ratio(u32 rate_in, u32 rate_out)
196{
197 u64 ratio;
198
199
200
201
202
203
204
205 ratio = (u64)rate_out << 20;
206 do_div(ratio, rate_in);
207
208 return ratio;
209}
210
211static unsigned long cs2000_ratio_to_rate(u32 ratio, u32 rate_in)
212{
213 u64 rate_out;
214
215
216
217
218
219
220
221
222 rate_out = (u64)ratio * rate_in;
223 return rate_out >> 20;
224}
225
226static 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
248static 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
266static 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
275
276
277
278 ret = cs2000_bset(priv, DEVICE_CFG1, RSEL_MASK, RSEL(ch));
279 if (ret < 0)
280 return ret;
281
282 ret = cs2000_bset(priv, DEVICE_CFG2,
283 (AUTORMOD | LOCKCLK_MASK | FRACNSRC_MASK),
284 (LOCKCLK(ch) | FRACNSRC_STATIC));
285 if (ret < 0)
286 return ret;
287
288 return 0;
289}
290
291static 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;
296 u32 ratio;
297
298 ratio = cs2000_ratio_get(priv, ch);
299
300 return cs2000_ratio_to_rate(ratio, parent_rate);
301}
302
303static 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
313static 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
331 priv->saved_rate = rate;
332 priv->saved_parent_rate = parent_rate;
333
334 return 0;
335}
336
337static 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;
342
343 return __cs2000_set_rate(priv, ch, rate, parent_rate);
344}
345
346static int cs2000_set_saved_rate(struct cs2000_priv *priv)
347{
348 int ch = 0;
349
350 return __cs2000_set_rate(priv, ch,
351 priv->saved_rate,
352 priv->saved_parent_rate);
353}
354
355static 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
375static 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
384static u8 cs2000_get_parent(struct clk_hw *hw)
385{
386
387 return REF_CLK;
388}
389
390static 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
399static int cs2000_clk_get(struct cs2000_priv *priv)
400{
401 struct device *dev = priv_to_dev(priv);
402 struct clk *clk_in, *ref_clk;
403
404 clk_in = devm_clk_get(dev, "clk_in");
405
406 if (IS_ERR(clk_in))
407 return -EPROBE_DEFER;
408
409 ref_clk = devm_clk_get(dev, "ref_clk");
410
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
420static 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;
426 static const char *parent_names[CLK_MAX];
427 int ch = 0;
428 int rate;
429 int ret;
430
431 of_property_read_string(np, "clock-output-names", &name);
432
433
434
435
436
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
454 ret = clk_hw_register(dev, &priv->hw);
455 if (ret)
456 return ret;
457
458 ret = of_clk_add_hw_provider(np, of_clk_hw_simple_get, &priv->hw);
459 if (ret < 0) {
460 clk_hw_unregister(&priv->hw);
461 return ret;
462 }
463
464 return 0;
465}
466
467static int cs2000_version_print(struct cs2000_priv *priv)
468{
469 struct device *dev = priv_to_dev(priv);
470 s32 val;
471 const char *revision;
472
473 val = cs2000_read(priv, DEVICE_ID);
474 if (val < 0)
475 return val;
476
477
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
497static int cs2000_remove(struct i2c_client *client)
498{
499 struct cs2000_priv *priv = i2c_get_clientdata(client);
500 struct device *dev = priv_to_dev(priv);
501 struct device_node *np = dev->of_node;
502
503 of_clk_del_provider(np);
504
505 clk_hw_unregister(&priv->hw);
506
507 return 0;
508}
509
510static 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
538probe_err:
539 cs2000_remove(client);
540
541 return ret;
542}
543
544static int cs2000_resume(struct device *dev)
545{
546 struct cs2000_priv *priv = dev_get_drvdata(dev);
547
548 return cs2000_set_saved_rate(priv);
549}
550
551static const struct dev_pm_ops cs2000_pm_ops = {
552 .resume_early = cs2000_resume,
553};
554
555static struct i2c_driver cs2000_driver = {
556 .driver = {
557 .name = "cs2000-cp",
558 .pm = &cs2000_pm_ops,
559 .of_match_table = cs2000_of_match,
560 },
561 .probe = cs2000_probe,
562 .remove = cs2000_remove,
563 .id_table = cs2000_id,
564};
565
566module_i2c_driver(cs2000_driver);
567
568MODULE_DESCRIPTION("CS2000-CP driver");
569MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
570MODULE_LICENSE("GPL v2");
571
