2 * CS2000 -- CIRRUS LOGIC Fractional-N Clock Synthesizer & Clock Multiplier
4 * Copyright (C) 2015 Renesas Electronics Corporation
5 * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
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.
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>
19 #define RATIO_REG_SIZE 4
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
33 #define REVISION_MASK (0x7)
34 #define REVISION_B2_B3 (0x4)
35 #define REVISION_C1 (0x6)
38 #define PLL_UNLOCK (1 << 7)
39 #define AUXOUTDIS (1 << 1)
40 #define CLKOUTDIS (1 << 0)
43 #define RSEL(x) (((x) & 0x3) << 3)
44 #define RSEL_MASK RSEL(0x3)
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)
59 #define CLKSKIPEN (1 << 7)
60 #define REFCLKDIV(x) (((x) & 0x3) << 3)
61 #define REFCLKDIV_MASK REFCLKDIV(0x3)
64 #define LFRATIO_MASK (1 << 3)
65 #define LFRATIO_20_12 (0 << 3)
66 #define LFRATIO_12_20 (1 << 3)
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))
79 struct i2c_client
*client
;
84 unsigned long saved_rate
;
85 unsigned long saved_parent_rate
;
88 static const struct of_device_id cs2000_of_match
[] = {
89 { .compatible
= "cirrus,cs2000-cp", },
92 MODULE_DEVICE_TABLE(of
, cs2000_of_match
);
94 static const struct i2c_device_id cs2000_id
[] = {
98 MODULE_DEVICE_TABLE(i2c
, cs2000_id
);
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)
105 static int cs2000_bset(struct cs2000_priv
*priv
, u8 addr
, u8 mask
, u8 val
)
109 data
= cs2000_read(priv
, addr
);
114 data
|= (val
& mask
);
116 return cs2000_write(priv
, addr
, data
);
119 static int cs2000_enable_dev_config(struct cs2000_priv
*priv
, bool enable
)
123 ret
= cs2000_bset(priv
, DEVICE_CFG1
, ENDEV1
,
124 enable
? ENDEV1
: 0);
128 ret
= cs2000_bset(priv
, GLOBAL_CFG
, ENDEV2
,
129 enable
? ENDEV2
: 0);
133 ret
= cs2000_bset(priv
, FUNC_CFG1
, CLKSKIPEN
,
134 enable
? CLKSKIPEN
: 0);
138 /* FIXME: for Static ratio mode */
139 ret
= cs2000_bset(priv
, FUNC_CFG2
, LFRATIO_MASK
,
147 static int cs2000_clk_in_bound_rate(struct cs2000_priv
*priv
,
152 if (rate_in
>= 32000000 && rate_in
< 56000000)
154 else if (rate_in
>= 16000000 && rate_in
< 28000000)
156 else if (rate_in
>= 8000000 && rate_in
< 14000000)
161 return cs2000_bset(priv
, FUNC_CFG1
,
166 static int cs2000_wait_pll_lock(struct cs2000_priv
*priv
)
168 struct device
*dev
= priv_to_dev(priv
);
172 for (i
= 0; i
< 256; i
++) {
173 val
= cs2000_read(priv
, DEVICE_CTRL
);
176 if (!(val
& PLL_UNLOCK
))
181 dev_err(dev
, "pll lock failed\n");
186 static int cs2000_clk_out_enable(struct cs2000_priv
*priv
, bool enable
)
188 /* enable both AUX_OUT, CLK_OUT */
189 return cs2000_bset(priv
, DEVICE_CTRL
,
190 (AUXOUTDIS
| CLKOUTDIS
),
192 (AUXOUTDIS
| CLKOUTDIS
));
195 static u32
cs2000_rate_to_ratio(u32 rate_in
, u32 rate_out
)
200 * ratio = rate_out / rate_in * 2^20
202 * To avoid over flow, rate_out is u64.
203 * The result should be u32.
205 ratio
= (u64
)rate_out
<< 20;
206 do_div(ratio
, rate_in
);
211 static unsigned long cs2000_ratio_to_rate(u32 ratio
, u32 rate_in
)
216 * ratio = rate_out / rate_in * 2^20
218 * To avoid over flow, rate_out is u64.
219 * The result should be u32 or unsigned long.
222 rate_out
= (u64
)ratio
* rate_in
;
223 return rate_out
>> 20;
226 static int cs2000_ratio_set(struct cs2000_priv
*priv
,
227 int ch
, u32 rate_in
, u32 rate_out
)
236 val
= cs2000_rate_to_ratio(rate_in
, rate_out
);
237 for (i
= 0; i
< RATIO_REG_SIZE
; i
++) {
238 ret
= cs2000_write(priv
,
248 static u32
cs2000_ratio_get(struct cs2000_priv
*priv
, int ch
)
255 for (i
= 0; i
< RATIO_REG_SIZE
; i
++) {
256 tmp
= cs2000_read(priv
, Ratio_Add(ch
, i
));
260 val
|= Val_Ratio(tmp
, i
);
266 static int cs2000_ratio_select(struct cs2000_priv
*priv
, int ch
)
276 * this driver supports static ratio mode only at this point.
278 ret
= cs2000_bset(priv
, DEVICE_CFG1
, RSEL_MASK
, RSEL(ch
));
282 ret
= cs2000_bset(priv
, DEVICE_CFG2
,
283 (AUTORMOD
| LOCKCLK_MASK
| FRACNSRC_MASK
),
284 (LOCKCLK(ch
) | FRACNSRC_STATIC
));
291 static unsigned long cs2000_recalc_rate(struct clk_hw
*hw
,
292 unsigned long parent_rate
)
294 struct cs2000_priv
*priv
= hw_to_priv(hw
);
295 int ch
= 0; /* it uses ch0 only at this point */
298 ratio
= cs2000_ratio_get(priv
, ch
);
300 return cs2000_ratio_to_rate(ratio
, parent_rate
);
303 static long cs2000_round_rate(struct clk_hw
*hw
, unsigned long rate
,
304 unsigned long *parent_rate
)
308 ratio
= cs2000_rate_to_ratio(*parent_rate
, rate
);
310 return cs2000_ratio_to_rate(ratio
, *parent_rate
);
313 static int __cs2000_set_rate(struct cs2000_priv
*priv
, int ch
,
314 unsigned long rate
, unsigned long parent_rate
)
319 ret
= cs2000_clk_in_bound_rate(priv
, parent_rate
);
323 ret
= cs2000_ratio_set(priv
, ch
, parent_rate
, rate
);
327 ret
= cs2000_ratio_select(priv
, ch
);
331 priv
->saved_rate
= rate
;
332 priv
->saved_parent_rate
= parent_rate
;
337 static int cs2000_set_rate(struct clk_hw
*hw
,
338 unsigned long rate
, unsigned long parent_rate
)
340 struct cs2000_priv
*priv
= hw_to_priv(hw
);
341 int ch
= 0; /* it uses ch0 only at this point */
343 return __cs2000_set_rate(priv
, ch
, rate
, parent_rate
);
346 static int cs2000_enable(struct clk_hw
*hw
)
348 struct cs2000_priv
*priv
= hw_to_priv(hw
);
351 ret
= cs2000_enable_dev_config(priv
, true);
355 ret
= cs2000_clk_out_enable(priv
, true);
359 ret
= cs2000_wait_pll_lock(priv
);
366 static void cs2000_disable(struct clk_hw
*hw
)
368 struct cs2000_priv
*priv
= hw_to_priv(hw
);
370 cs2000_enable_dev_config(priv
, false);
372 cs2000_clk_out_enable(priv
, false);
375 static u8
cs2000_get_parent(struct clk_hw
*hw
)
377 /* always return REF_CLK */
381 static const struct clk_ops cs2000_ops
= {
382 .get_parent
= cs2000_get_parent
,
383 .recalc_rate
= cs2000_recalc_rate
,
384 .round_rate
= cs2000_round_rate
,
385 .set_rate
= cs2000_set_rate
,
386 .prepare
= cs2000_enable
,
387 .unprepare
= cs2000_disable
,
390 static int cs2000_clk_get(struct cs2000_priv
*priv
)
392 struct device
*dev
= priv_to_dev(priv
);
393 struct clk
*clk_in
, *ref_clk
;
395 clk_in
= devm_clk_get(dev
, "clk_in");
396 /* not yet provided */
398 return -EPROBE_DEFER
;
400 ref_clk
= devm_clk_get(dev
, "ref_clk");
401 /* not yet provided */
403 return -EPROBE_DEFER
;
405 priv
->clk_in
= clk_in
;
406 priv
->ref_clk
= ref_clk
;
411 static int cs2000_clk_register(struct cs2000_priv
*priv
)
413 struct device
*dev
= priv_to_dev(priv
);
414 struct device_node
*np
= dev
->of_node
;
415 struct clk_init_data init
;
416 const char *name
= np
->name
;
417 static const char *parent_names
[CLK_MAX
];
418 int ch
= 0; /* it uses ch0 only at this point */
422 of_property_read_string(np
, "clock-output-names", &name
);
425 * set default rate as 1/1.
426 * otherwise .set_rate which setup ratio
427 * is never called if user requests 1/1 rate
429 rate
= clk_get_rate(priv
->ref_clk
);
430 ret
= __cs2000_set_rate(priv
, ch
, rate
, rate
);
434 parent_names
[CLK_IN
] = __clk_get_name(priv
->clk_in
);
435 parent_names
[REF_CLK
] = __clk_get_name(priv
->ref_clk
);
438 init
.ops
= &cs2000_ops
;
439 init
.flags
= CLK_SET_RATE_GATE
;
440 init
.parent_names
= parent_names
;
441 init
.num_parents
= ARRAY_SIZE(parent_names
);
443 priv
->hw
.init
= &init
;
445 ret
= clk_hw_register(dev
, &priv
->hw
);
449 ret
= of_clk_add_hw_provider(np
, of_clk_hw_simple_get
, &priv
->hw
);
451 clk_hw_unregister(&priv
->hw
);
458 static int cs2000_version_print(struct cs2000_priv
*priv
)
460 struct device
*dev
= priv_to_dev(priv
);
462 const char *revision
;
464 val
= cs2000_read(priv
, DEVICE_ID
);
468 /* CS2000 should be 0x0 */
472 switch (val
& REVISION_MASK
) {
474 revision
= "B2 / B3";
483 dev_info(dev
, "revision - %s\n", revision
);
488 static int cs2000_remove(struct i2c_client
*client
)
490 struct cs2000_priv
*priv
= i2c_get_clientdata(client
);
491 struct device
*dev
= priv_to_dev(priv
);
492 struct device_node
*np
= dev
->of_node
;
494 of_clk_del_provider(np
);
496 clk_hw_unregister(&priv
->hw
);
501 static int cs2000_probe(struct i2c_client
*client
,
502 const struct i2c_device_id
*id
)
504 struct cs2000_priv
*priv
;
505 struct device
*dev
= &client
->dev
;
508 priv
= devm_kzalloc(dev
, sizeof(*priv
), GFP_KERNEL
);
512 priv
->client
= client
;
513 i2c_set_clientdata(client
, priv
);
515 ret
= cs2000_clk_get(priv
);
519 ret
= cs2000_clk_register(priv
);
523 ret
= cs2000_version_print(priv
);
530 cs2000_remove(client
);
535 static int cs2000_resume(struct device
*dev
)
537 struct cs2000_priv
*priv
= dev_get_drvdata(dev
);
538 int ch
= 0; /* it uses ch0 only at this point */
540 return __cs2000_set_rate(priv
, ch
,
542 priv
->saved_parent_rate
);
545 static const struct dev_pm_ops cs2000_pm_ops
= {
546 .resume_early
= cs2000_resume
,
549 static struct i2c_driver cs2000_driver
= {
552 .pm
= &cs2000_pm_ops
,
553 .of_match_table
= cs2000_of_match
,
555 .probe
= cs2000_probe
,
556 .remove
= cs2000_remove
,
557 .id_table
= cs2000_id
,
560 module_i2c_driver(cs2000_driver
);
562 MODULE_DESCRIPTION("CS2000-CP driver");
563 MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
564 MODULE_LICENSE("GPL v2");