1 /*
2 * Driver for IDT Versaclock 5
3 *
4 * Copyright (C) 2017 Marek Vasut <marek.vasut@gmail.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 */
16
17 /*
18 * Possible optimizations:
19 * - Use spread spectrum
20 * - Use integer divider in FOD if applicable
21 */
22
23 #include <linux/clk.h>
24 #include <linux/clk-provider.h>
25 #include <linux/delay.h>
26 #include <linux/i2c.h>
27 #include <linux/interrupt.h>
28 #include <linux/mod_devicetable.h>
29 #include <linux/module.h>
30 #include <linux/of.h>
31 #include <linux/of_platform.h>
32 #include <linux/rational.h>
33 #include <linux/regmap.h>
34 #include <linux/slab.h>
35
36 /* VersaClock5 registers */
37 #define VC5_OTP_CONTROL 0x00
38
39 /* Factory-reserved register block */
40 #define VC5_RSVD_DEVICE_ID 0x01
41 #define VC5_RSVD_ADC_GAIN_7_0 0x02
42 #define VC5_RSVD_ADC_GAIN_15_8 0x03
43 #define VC5_RSVD_ADC_OFFSET_7_0 0x04
44 #define VC5_RSVD_ADC_OFFSET_15_8 0x05
45 #define VC5_RSVD_TEMPY 0x06
46 #define VC5_RSVD_OFFSET_TBIN 0x07
47 #define VC5_RSVD_GAIN 0x08
48 #define VC5_RSVD_TEST_NP 0x09
49 #define VC5_RSVD_UNUSED 0x0a
50 #define VC5_RSVD_BANDGAP_TRIM_UP 0x0b
51 #define VC5_RSVD_BANDGAP_TRIM_DN 0x0c
52 #define VC5_RSVD_CLK_R_12_CLK_AMP_4 0x0d
53 #define VC5_RSVD_CLK_R_34_CLK_AMP_4 0x0e
54 #define VC5_RSVD_CLK_AMP_123 0x0f
55
56 /* Configuration register block */
57 #define VC5_PRIM_SRC_SHDN 0x10
58 #define VC5_PRIM_SRC_SHDN_EN_XTAL BIT(7)
59 #define VC5_PRIM_SRC_SHDN_EN_CLKIN BIT(6)
60 #define VC5_PRIM_SRC_SHDN_EN_DOUBLE_XTAL_FREQ BIT(3)
61 #define VC5_PRIM_SRC_SHDN_SP BIT(1)
62 #define VC5_PRIM_SRC_SHDN_EN_GBL_SHDN BIT(0)
63
64 #define VC5_VCO_BAND 0x11
65 #define VC5_XTAL_X1_LOAD_CAP 0x12
66 #define VC5_XTAL_X2_LOAD_CAP 0x13
67 #define VC5_REF_DIVIDER 0x15
68 #define VC5_REF_DIVIDER_SEL_PREDIV2 BIT(7)
69 #define VC5_REF_DIVIDER_REF_DIV(n) ((n) & 0x3f)
70
71 #define VC5_VCO_CTRL_AND_PREDIV 0x16
72 #define VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV BIT(7)
73
74 #define VC5_FEEDBACK_INT_DIV 0x17
75 #define VC5_FEEDBACK_INT_DIV_BITS 0x18
76 #define VC5_FEEDBACK_FRAC_DIV(n) (0x19 + (n))
77 #define VC5_RC_CONTROL0 0x1e
78 #define VC5_RC_CONTROL1 0x1f
79 /* Register 0x20 is factory reserved */
80
81 /* Output divider control for divider 1,2,3,4 */
82 #define VC5_OUT_DIV_CONTROL(idx) (0x21 + ((idx) * 0x10))
83 #define VC5_OUT_DIV_CONTROL_RESET BIT(7)
84 #define VC5_OUT_DIV_CONTROL_SELB_NORM BIT(3)
85 #define VC5_OUT_DIV_CONTROL_SEL_EXT BIT(2)
86 #define VC5_OUT_DIV_CONTROL_INT_MODE BIT(1)
87 #define VC5_OUT_DIV_CONTROL_EN_FOD BIT(0)
88
89 #define VC5_OUT_DIV_FRAC(idx, n) (0x22 + ((idx) * 0x10) + (n))
90 #define VC5_OUT_DIV_FRAC4_OD_SCEE BIT(1)
91
92 #define VC5_OUT_DIV_STEP_SPREAD(idx, n) (0x26 + ((idx) * 0x10) + (n))
93 #define VC5_OUT_DIV_SPREAD_MOD(idx, n) (0x29 + ((idx) * 0x10) + (n))
94 #define VC5_OUT_DIV_SKEW_INT(idx, n) (0x2b + ((idx) * 0x10) + (n))
95 #define VC5_OUT_DIV_INT(idx, n) (0x2d + ((idx) * 0x10) + (n))
96 #define VC5_OUT_DIV_SKEW_FRAC(idx) (0x2f + ((idx) * 0x10))
97 /* Registers 0x30, 0x40, 0x50 are factory reserved */
98
99 /* Clock control register for clock 1,2 */
100 #define VC5_CLK_OUTPUT_CFG(idx, n) (0x60 + ((idx) * 0x2) + (n))
101 #define VC5_CLK_OUTPUT_CFG1_EN_CLKBUF BIT(0)
102
103 #define VC5_CLK_OE_SHDN 0x68
104 #define VC5_CLK_OS_SHDN 0x69
105
106 #define VC5_GLOBAL_REGISTER 0x76
107 #define VC5_GLOBAL_REGISTER_GLOBAL_RESET BIT(5)
108
109 /* PLL/VCO runs between 2.5 GHz and 3.0 GHz */
110 #define VC5_PLL_VCO_MIN 2500000000UL
111 #define VC5_PLL_VCO_MAX 3000000000UL
112
113 /* VC5 Input mux settings */
114 #define VC5_MUX_IN_XIN BIT(0)
115 #define VC5_MUX_IN_CLKIN BIT(1)
116
117 /* Maximum number of clk_out supported by this driver */
118 #define VC5_MAX_CLK_OUT_NUM 5
119
120 /* Maximum number of FODs supported by this driver */
121 #define VC5_MAX_FOD_NUM 4
122
123 /* flags to describe chip features */
124 /* chip has built-in oscilator */
125 #define VC5_HAS_INTERNAL_XTAL BIT(0)
126 /* chip has PFD requency doubler */
127 #define VC5_HAS_PFD_FREQ_DBL BIT(1)
128
129 /* Supported IDT VC5 models. */
130 enum vc5_model {
131 IDT_VC5_5P49V5923,
132 IDT_VC5_5P49V5925,
133 IDT_VC5_5P49V5933,
134 IDT_VC5_5P49V5935,
135 IDT_VC6_5P49V6901,
136 };
137
138 /* Structure to describe features of a particular VC5 model */
139 struct vc5_chip_info {
140 const enum vc5_model model;
141 const unsigned int clk_fod_cnt;
142 const unsigned int clk_out_cnt;
143 const u32 flags;
144 };
145
146 struct vc5_driver_data;
147
148 struct vc5_hw_data {
149 struct clk_hw hw;
150 struct vc5_driver_data *vc5;
151 u32 div_int;
152 u32 div_frc;
153 unsigned int num;
154 };
155
156 struct vc5_driver_data {
157 struct i2c_client *client;
158 struct regmap *regmap;
159 const struct vc5_chip_info *chip_info;
160
161 struct clk *pin_xin;
162 struct clk *pin_clkin;
163 unsigned char clk_mux_ins;
164 struct clk_hw clk_mux;
165 struct clk_hw clk_mul;
166 struct clk_hw clk_pfd;
167 struct vc5_hw_data clk_pll;
168 struct vc5_hw_data clk_fod[VC5_MAX_FOD_NUM];
169 struct vc5_hw_data clk_out[VC5_MAX_CLK_OUT_NUM];
170 };
171
172 static const char * const vc5_mux_names[] = {
173 "mux"
174 };
175
176 static const char * const vc5_dbl_names[] = {
177 "dbl"
178 };
179
180 static const char * const vc5_pfd_names[] = {
181 "pfd"
182 };
183
184 static const char * const vc5_pll_names[] = {
185 "pll"
186 };
187
188 static const char * const vc5_fod_names[] = {
189 "fod0", "fod1", "fod2", "fod3",
190 };
191
192 static const char * const vc5_clk_out_names[] = {
193 "out0_sel_i2cb", "out1", "out2", "out3", "out4",
194 };
195
196 /*
197 * VersaClock5 i2c regmap
198 */
vc5_regmap_is_writeable(struct device * dev,unsigned int reg)199 static bool vc5_regmap_is_writeable(struct device *dev, unsigned int reg)
200 {
201 /* Factory reserved regs, make them read-only */
202 if (reg <= 0xf)
203 return false;
204
205 /* Factory reserved regs, make them read-only */
206 if (reg == 0x14 || reg == 0x1c || reg == 0x1d)
207 return false;
208
209 return true;
210 }
211
212 static const struct regmap_config vc5_regmap_config = {
213 .reg_bits = 8,
214 .val_bits = 8,
215 .cache_type = REGCACHE_RBTREE,
216 .max_register = 0x76,
217 .writeable_reg = vc5_regmap_is_writeable,
218 };
219
220 /*
221 * VersaClock5 input multiplexer between XTAL and CLKIN divider
222 */
vc5_mux_get_parent(struct clk_hw * hw)223 static unsigned char vc5_mux_get_parent(struct clk_hw *hw)
224 {
225 struct vc5_driver_data *vc5 =
226 container_of(hw, struct vc5_driver_data, clk_mux);
227 const u8 mask = VC5_PRIM_SRC_SHDN_EN_XTAL | VC5_PRIM_SRC_SHDN_EN_CLKIN;
228 unsigned int src;
229
230 regmap_read(vc5->regmap, VC5_PRIM_SRC_SHDN, &src);
231 src &= mask;
232
233 if (src == VC5_PRIM_SRC_SHDN_EN_XTAL)
234 return 0;
235
236 if (src == VC5_PRIM_SRC_SHDN_EN_CLKIN)
237 return 1;
238
239 dev_warn(&vc5->client->dev,
240 "Invalid clock input configuration (%02x)\n", src);
241 return 0;
242 }
243
vc5_mux_set_parent(struct clk_hw * hw,u8 index)244 static int vc5_mux_set_parent(struct clk_hw *hw, u8 index)
245 {
246 struct vc5_driver_data *vc5 =
247 container_of(hw, struct vc5_driver_data, clk_mux);
248 const u8 mask = VC5_PRIM_SRC_SHDN_EN_XTAL | VC5_PRIM_SRC_SHDN_EN_CLKIN;
249 u8 src;
250
251 if ((index > 1) || !vc5->clk_mux_ins)
252 return -EINVAL;
253
254 if (vc5->clk_mux_ins == (VC5_MUX_IN_CLKIN | VC5_MUX_IN_XIN)) {
255 if (index == 0)
256 src = VC5_PRIM_SRC_SHDN_EN_XTAL;
257 if (index == 1)
258 src = VC5_PRIM_SRC_SHDN_EN_CLKIN;
259 } else {
260 if (index != 0)
261 return -EINVAL;
262
263 if (vc5->clk_mux_ins == VC5_MUX_IN_XIN)
264 src = VC5_PRIM_SRC_SHDN_EN_XTAL;
265 else if (vc5->clk_mux_ins == VC5_MUX_IN_CLKIN)
266 src = VC5_PRIM_SRC_SHDN_EN_CLKIN;
267 else /* Invalid; should have been caught by vc5_probe() */
268 return -EINVAL;
269 }
270
271 return regmap_update_bits(vc5->regmap, VC5_PRIM_SRC_SHDN, mask, src);
272 }
273
274 static const struct clk_ops vc5_mux_ops = {
275 .set_parent = vc5_mux_set_parent,
276 .get_parent = vc5_mux_get_parent,
277 };
278
vc5_dbl_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)279 static unsigned long vc5_dbl_recalc_rate(struct clk_hw *hw,
280 unsigned long parent_rate)
281 {
282 struct vc5_driver_data *vc5 =
283 container_of(hw, struct vc5_driver_data, clk_mul);
284 unsigned int premul;
285
286 regmap_read(vc5->regmap, VC5_PRIM_SRC_SHDN, &premul);
287 if (premul & VC5_PRIM_SRC_SHDN_EN_DOUBLE_XTAL_FREQ)
288 parent_rate *= 2;
289
290 return parent_rate;
291 }
292
vc5_dbl_round_rate(struct clk_hw * hw,unsigned long rate,unsigned long * parent_rate)293 static long vc5_dbl_round_rate(struct clk_hw *hw, unsigned long rate,
294 unsigned long *parent_rate)
295 {
296 if ((*parent_rate == rate) || ((*parent_rate * 2) == rate))
297 return rate;
298 else
299 return -EINVAL;
300 }
301
vc5_dbl_set_rate(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)302 static int vc5_dbl_set_rate(struct clk_hw *hw, unsigned long rate,
303 unsigned long parent_rate)
304 {
305 struct vc5_driver_data *vc5 =
306 container_of(hw, struct vc5_driver_data, clk_mul);
307 u32 mask;
308
309 if ((parent_rate * 2) == rate)
310 mask = VC5_PRIM_SRC_SHDN_EN_DOUBLE_XTAL_FREQ;
311 else
312 mask = 0;
313
314 regmap_update_bits(vc5->regmap, VC5_PRIM_SRC_SHDN,
315 VC5_PRIM_SRC_SHDN_EN_DOUBLE_XTAL_FREQ,
316 mask);
317
318 return 0;
319 }
320
321 static const struct clk_ops vc5_dbl_ops = {
322 .recalc_rate = vc5_dbl_recalc_rate,
323 .round_rate = vc5_dbl_round_rate,
324 .set_rate = vc5_dbl_set_rate,
325 };
326
vc5_pfd_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)327 static unsigned long vc5_pfd_recalc_rate(struct clk_hw *hw,
328 unsigned long parent_rate)
329 {
330 struct vc5_driver_data *vc5 =
331 container_of(hw, struct vc5_driver_data, clk_pfd);
332 unsigned int prediv, div;
333
334 regmap_read(vc5->regmap, VC5_VCO_CTRL_AND_PREDIV, &prediv);
335
336 /* The bypass_prediv is set, PLL fed from Ref_in directly. */
337 if (prediv & VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV)
338 return parent_rate;
339
340 regmap_read(vc5->regmap, VC5_REF_DIVIDER, &div);
341
342 /* The Sel_prediv2 is set, PLL fed from prediv2 (Ref_in / 2) */
343 if (div & VC5_REF_DIVIDER_SEL_PREDIV2)
344 return parent_rate / 2;
345 else
346 return parent_rate / VC5_REF_DIVIDER_REF_DIV(div);
347 }
348
vc5_pfd_round_rate(struct clk_hw * hw,unsigned long rate,unsigned long * parent_rate)349 static long vc5_pfd_round_rate(struct clk_hw *hw, unsigned long rate,
350 unsigned long *parent_rate)
351 {
352 unsigned long idiv;
353
354 /* PLL cannot operate with input clock above 50 MHz. */
355 if (rate > 50000000)
356 return -EINVAL;
357
358 /* CLKIN within range of PLL input, feed directly to PLL. */
359 if (*parent_rate <= 50000000)
360 return *parent_rate;
361
362 idiv = DIV_ROUND_UP(*parent_rate, rate);
363 if (idiv > 127)
364 return -EINVAL;
365
366 return *parent_rate / idiv;
367 }
368
vc5_pfd_set_rate(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)369 static int vc5_pfd_set_rate(struct clk_hw *hw, unsigned long rate,
370 unsigned long parent_rate)
371 {
372 struct vc5_driver_data *vc5 =
373 container_of(hw, struct vc5_driver_data, clk_pfd);
374 unsigned long idiv;
375 u8 div;
376
377 /* CLKIN within range of PLL input, feed directly to PLL. */
378 if (parent_rate <= 50000000) {
379 regmap_update_bits(vc5->regmap, VC5_VCO_CTRL_AND_PREDIV,
380 VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV,
381 VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV);
382 regmap_update_bits(vc5->regmap, VC5_REF_DIVIDER, 0xff, 0x00);
383 return 0;
384 }
385
386 idiv = DIV_ROUND_UP(parent_rate, rate);
387
388 /* We have dedicated div-2 predivider. */
389 if (idiv == 2)
390 div = VC5_REF_DIVIDER_SEL_PREDIV2;
391 else
392 div = VC5_REF_DIVIDER_REF_DIV(idiv);
393
394 regmap_update_bits(vc5->regmap, VC5_REF_DIVIDER, 0xff, div);
395 regmap_update_bits(vc5->regmap, VC5_VCO_CTRL_AND_PREDIV,
396 VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV, 0);
397
398 return 0;
399 }
400
401 static const struct clk_ops vc5_pfd_ops = {
402 .recalc_rate = vc5_pfd_recalc_rate,
403 .round_rate = vc5_pfd_round_rate,
404 .set_rate = vc5_pfd_set_rate,
405 };
406
407 /*
408 * VersaClock5 PLL/VCO
409 */
vc5_pll_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)410 static unsigned long vc5_pll_recalc_rate(struct clk_hw *hw,
411 unsigned long parent_rate)
412 {
413 struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
414 struct vc5_driver_data *vc5 = hwdata->vc5;
415 u32 div_int, div_frc;
416 u8 fb[5];
417
418 regmap_bulk_read(vc5->regmap, VC5_FEEDBACK_INT_DIV, fb, 5);
419
420 div_int = (fb[0] << 4) | (fb[1] >> 4);
421 div_frc = (fb[2] << 16) | (fb[3] << 8) | fb[4];
422
423 /* The PLL divider has 12 integer bits and 24 fractional bits */
424 return (parent_rate * div_int) + ((parent_rate * div_frc) >> 24);
425 }
426
vc5_pll_round_rate(struct clk_hw * hw,unsigned long rate,unsigned long * parent_rate)427 static long vc5_pll_round_rate(struct clk_hw *hw, unsigned long rate,
428 unsigned long *parent_rate)
429 {
430 struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
431 u32 div_int;
432 u64 div_frc;
433
434 if (rate < VC5_PLL_VCO_MIN)
435 rate = VC5_PLL_VCO_MIN;
436 if (rate > VC5_PLL_VCO_MAX)
437 rate = VC5_PLL_VCO_MAX;
438
439 /* Determine integer part, which is 12 bit wide */
440 div_int = rate / *parent_rate;
441 if (div_int > 0xfff)
442 rate = *parent_rate * 0xfff;
443
444 /* Determine best fractional part, which is 24 bit wide */
445 div_frc = rate % *parent_rate;
446 div_frc *= BIT(24) - 1;
447 do_div(div_frc, *parent_rate);
448
449 hwdata->div_int = div_int;
450 hwdata->div_frc = (u32)div_frc;
451
452 return (*parent_rate * div_int) + ((*parent_rate * div_frc) >> 24);
453 }
454
vc5_pll_set_rate(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)455 static int vc5_pll_set_rate(struct clk_hw *hw, unsigned long rate,
456 unsigned long parent_rate)
457 {
458 struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
459 struct vc5_driver_data *vc5 = hwdata->vc5;
460 u8 fb[5];
461
462 fb[0] = hwdata->div_int >> 4;
463 fb[1] = hwdata->div_int << 4;
464 fb[2] = hwdata->div_frc >> 16;
465 fb[3] = hwdata->div_frc >> 8;
466 fb[4] = hwdata->div_frc;
467
468 return regmap_bulk_write(vc5->regmap, VC5_FEEDBACK_INT_DIV, fb, 5);
469 }
470
471 static const struct clk_ops vc5_pll_ops = {
472 .recalc_rate = vc5_pll_recalc_rate,
473 .round_rate = vc5_pll_round_rate,
474 .set_rate = vc5_pll_set_rate,
475 };
476
vc5_fod_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)477 static unsigned long vc5_fod_recalc_rate(struct clk_hw *hw,
478 unsigned long parent_rate)
479 {
480 struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
481 struct vc5_driver_data *vc5 = hwdata->vc5;
482 /* VCO frequency is divided by two before entering FOD */
483 u32 f_in = parent_rate / 2;
484 u32 div_int, div_frc;
485 u8 od_int[2];
486 u8 od_frc[4];
487
488 regmap_bulk_read(vc5->regmap, VC5_OUT_DIV_INT(hwdata->num, 0),
489 od_int, 2);
490 regmap_bulk_read(vc5->regmap, VC5_OUT_DIV_FRAC(hwdata->num, 0),
491 od_frc, 4);
492
493 div_int = (od_int[0] << 4) | (od_int[1] >> 4);
494 div_frc = (od_frc[0] << 22) | (od_frc[1] << 14) |
495 (od_frc[2] << 6) | (od_frc[3] >> 2);
496
497 /* Avoid division by zero if the output is not configured. */
498 if (div_int == 0 && div_frc == 0)
499 return 0;
500
501 /* The PLL divider has 12 integer bits and 30 fractional bits */
502 return div64_u64((u64)f_in << 24ULL, ((u64)div_int << 24ULL) + div_frc);
503 }
504
vc5_fod_round_rate(struct clk_hw * hw,unsigned long rate,unsigned long * parent_rate)505 static long vc5_fod_round_rate(struct clk_hw *hw, unsigned long rate,
506 unsigned long *parent_rate)
507 {
508 struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
509 /* VCO frequency is divided by two before entering FOD */
510 u32 f_in = *parent_rate / 2;
511 u32 div_int;
512 u64 div_frc;
513
514 /* Determine integer part, which is 12 bit wide */
515 div_int = f_in / rate;
516 /*
517 * WARNING: The clock chip does not output signal if the integer part
518 * of the divider is 0xfff and fractional part is non-zero.
519 * Clamp the divider at 0xffe to keep the code simple.
520 */
521 if (div_int > 0xffe) {
522 div_int = 0xffe;
523 rate = f_in / div_int;
524 }
525
526 /* Determine best fractional part, which is 30 bit wide */
527 div_frc = f_in % rate;
528 div_frc <<= 24;
529 do_div(div_frc, rate);
530
531 hwdata->div_int = div_int;
532 hwdata->div_frc = (u32)div_frc;
533
534 return div64_u64((u64)f_in << 24ULL, ((u64)div_int << 24ULL) + div_frc);
535 }
536
vc5_fod_set_rate(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)537 static int vc5_fod_set_rate(struct clk_hw *hw, unsigned long rate,
538 unsigned long parent_rate)
539 {
540 struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
541 struct vc5_driver_data *vc5 = hwdata->vc5;
542 u8 data[14] = {
543 hwdata->div_frc >> 22, hwdata->div_frc >> 14,
544 hwdata->div_frc >> 6, hwdata->div_frc << 2,
545 0, 0, 0, 0, 0,
546 0, 0,
547 hwdata->div_int >> 4, hwdata->div_int << 4,
548 0
549 };
550
551 regmap_bulk_write(vc5->regmap, VC5_OUT_DIV_FRAC(hwdata->num, 0),
552 data, 14);
553
554 /*
555 * Toggle magic bit in undocumented register for unknown reason.
556 * This is what the IDT timing commander tool does and the chip
557 * datasheet somewhat implies this is needed, but the register
558 * and the bit is not documented.
559 */
560 regmap_update_bits(vc5->regmap, VC5_GLOBAL_REGISTER,
561 VC5_GLOBAL_REGISTER_GLOBAL_RESET, 0);
562 regmap_update_bits(vc5->regmap, VC5_GLOBAL_REGISTER,
563 VC5_GLOBAL_REGISTER_GLOBAL_RESET,
564 VC5_GLOBAL_REGISTER_GLOBAL_RESET);
565 return 0;
566 }
567
568 static const struct clk_ops vc5_fod_ops = {
569 .recalc_rate = vc5_fod_recalc_rate,
570 .round_rate = vc5_fod_round_rate,
571 .set_rate = vc5_fod_set_rate,
572 };
573
vc5_clk_out_prepare(struct clk_hw * hw)574 static int vc5_clk_out_prepare(struct clk_hw *hw)
575 {
576 struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
577 struct vc5_driver_data *vc5 = hwdata->vc5;
578 const u8 mask = VC5_OUT_DIV_CONTROL_SELB_NORM |
579 VC5_OUT_DIV_CONTROL_SEL_EXT |
580 VC5_OUT_DIV_CONTROL_EN_FOD;
581 unsigned int src;
582 int ret;
583
584 /*
585 * If the input mux is disabled, enable it first and
586 * select source from matching FOD.
587 */
588 regmap_read(vc5->regmap, VC5_OUT_DIV_CONTROL(hwdata->num), &src);
589 if ((src & mask) == 0) {
590 src = VC5_OUT_DIV_CONTROL_RESET | VC5_OUT_DIV_CONTROL_EN_FOD;
591 ret = regmap_update_bits(vc5->regmap,
592 VC5_OUT_DIV_CONTROL(hwdata->num),
593 mask | VC5_OUT_DIV_CONTROL_RESET, src);
594 if (ret)
595 return ret;
596 }
597
598 /* Enable the clock buffer */
599 regmap_update_bits(vc5->regmap, VC5_CLK_OUTPUT_CFG(hwdata->num, 1),
600 VC5_CLK_OUTPUT_CFG1_EN_CLKBUF,
601 VC5_CLK_OUTPUT_CFG1_EN_CLKBUF);
602 return 0;
603 }
604
vc5_clk_out_unprepare(struct clk_hw * hw)605 static void vc5_clk_out_unprepare(struct clk_hw *hw)
606 {
607 struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
608 struct vc5_driver_data *vc5 = hwdata->vc5;
609
610 /* Disable the clock buffer */
611 regmap_update_bits(vc5->regmap, VC5_CLK_OUTPUT_CFG(hwdata->num, 1),
612 VC5_CLK_OUTPUT_CFG1_EN_CLKBUF, 0);
613 }
614
vc5_clk_out_get_parent(struct clk_hw * hw)615 static unsigned char vc5_clk_out_get_parent(struct clk_hw *hw)
616 {
617 struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
618 struct vc5_driver_data *vc5 = hwdata->vc5;
619 const u8 mask = VC5_OUT_DIV_CONTROL_SELB_NORM |
620 VC5_OUT_DIV_CONTROL_SEL_EXT |
621 VC5_OUT_DIV_CONTROL_EN_FOD;
622 const u8 fodclkmask = VC5_OUT_DIV_CONTROL_SELB_NORM |
623 VC5_OUT_DIV_CONTROL_EN_FOD;
624 const u8 extclk = VC5_OUT_DIV_CONTROL_SELB_NORM |
625 VC5_OUT_DIV_CONTROL_SEL_EXT;
626 unsigned int src;
627
628 regmap_read(vc5->regmap, VC5_OUT_DIV_CONTROL(hwdata->num), &src);
629 src &= mask;
630
631 if (src == 0) /* Input mux set to DISABLED */
632 return 0;
633
634 if ((src & fodclkmask) == VC5_OUT_DIV_CONTROL_EN_FOD)
635 return 0;
636
637 if (src == extclk)
638 return 1;
639
640 dev_warn(&vc5->client->dev,
641 "Invalid clock output configuration (%02x)\n", src);
642 return 0;
643 }
644
vc5_clk_out_set_parent(struct clk_hw * hw,u8 index)645 static int vc5_clk_out_set_parent(struct clk_hw *hw, u8 index)
646 {
647 struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
648 struct vc5_driver_data *vc5 = hwdata->vc5;
649 const u8 mask = VC5_OUT_DIV_CONTROL_RESET |
650 VC5_OUT_DIV_CONTROL_SELB_NORM |
651 VC5_OUT_DIV_CONTROL_SEL_EXT |
652 VC5_OUT_DIV_CONTROL_EN_FOD;
653 const u8 extclk = VC5_OUT_DIV_CONTROL_SELB_NORM |
654 VC5_OUT_DIV_CONTROL_SEL_EXT;
655 u8 src = VC5_OUT_DIV_CONTROL_RESET;
656
657 if (index == 0)
658 src |= VC5_OUT_DIV_CONTROL_EN_FOD;
659 else
660 src |= extclk;
661
662 return regmap_update_bits(vc5->regmap, VC5_OUT_DIV_CONTROL(hwdata->num),
663 mask, src);
664 }
665
666 static const struct clk_ops vc5_clk_out_ops = {
667 .prepare = vc5_clk_out_prepare,
668 .unprepare = vc5_clk_out_unprepare,
669 .set_parent = vc5_clk_out_set_parent,
670 .get_parent = vc5_clk_out_get_parent,
671 };
672
vc5_of_clk_get(struct of_phandle_args * clkspec,void * data)673 static struct clk_hw *vc5_of_clk_get(struct of_phandle_args *clkspec,
674 void *data)
675 {
676 struct vc5_driver_data *vc5 = data;
677 unsigned int idx = clkspec->args[0];
678
679 if (idx >= vc5->chip_info->clk_out_cnt)
680 return ERR_PTR(-EINVAL);
681
682 return &vc5->clk_out[idx].hw;
683 }
684
vc5_map_index_to_output(const enum vc5_model model,const unsigned int n)685 static int vc5_map_index_to_output(const enum vc5_model model,
686 const unsigned int n)
687 {
688 switch (model) {
689 case IDT_VC5_5P49V5933:
690 return (n == 0) ? 0 : 3;
691 case IDT_VC5_5P49V5923:
692 case IDT_VC5_5P49V5925:
693 case IDT_VC5_5P49V5935:
694 case IDT_VC6_5P49V6901:
695 default:
696 return n;
697 }
698 }
699
700 static const struct of_device_id clk_vc5_of_match[];
701
vc5_probe(struct i2c_client * client,const struct i2c_device_id * id)702 static int vc5_probe(struct i2c_client *client,
703 const struct i2c_device_id *id)
704 {
705 struct vc5_driver_data *vc5;
706 struct clk_init_data init;
707 const char *parent_names[2];
708 unsigned int n, idx = 0;
709 int ret;
710
711 vc5 = devm_kzalloc(&client->dev, sizeof(*vc5), GFP_KERNEL);
712 if (vc5 == NULL)
713 return -ENOMEM;
714
715 i2c_set_clientdata(client, vc5);
716 vc5->client = client;
717 vc5->chip_info = of_device_get_match_data(&client->dev);
718
719 vc5->pin_xin = devm_clk_get(&client->dev, "xin");
720 if (PTR_ERR(vc5->pin_xin) == -EPROBE_DEFER)
721 return -EPROBE_DEFER;
722
723 vc5->pin_clkin = devm_clk_get(&client->dev, "clkin");
724 if (PTR_ERR(vc5->pin_clkin) == -EPROBE_DEFER)
725 return -EPROBE_DEFER;
726
727 vc5->regmap = devm_regmap_init_i2c(client, &vc5_regmap_config);
728 if (IS_ERR(vc5->regmap)) {
729 dev_err(&client->dev, "failed to allocate register map\n");
730 return PTR_ERR(vc5->regmap);
731 }
732
733 /* Register clock input mux */
734 memset(&init, 0, sizeof(init));
735
736 if (!IS_ERR(vc5->pin_xin)) {
737 vc5->clk_mux_ins |= VC5_MUX_IN_XIN;
738 parent_names[init.num_parents++] = __clk_get_name(vc5->pin_xin);
739 } else if (vc5->chip_info->flags & VC5_HAS_INTERNAL_XTAL) {
740 vc5->pin_xin = clk_register_fixed_rate(&client->dev,
741 "internal-xtal", NULL,
742 0, 25000000);
743 if (IS_ERR(vc5->pin_xin))
744 return PTR_ERR(vc5->pin_xin);
745 vc5->clk_mux_ins |= VC5_MUX_IN_XIN;
746 parent_names[init.num_parents++] = __clk_get_name(vc5->pin_xin);
747 }
748
749 if (!IS_ERR(vc5->pin_clkin)) {
750 vc5->clk_mux_ins |= VC5_MUX_IN_CLKIN;
751 parent_names[init.num_parents++] =
752 __clk_get_name(vc5->pin_clkin);
753 }
754
755 if (!init.num_parents) {
756 dev_err(&client->dev, "no input clock specified!\n");
757 return -EINVAL;
758 }
759
760 init.name = vc5_mux_names[0];
761 init.ops = &vc5_mux_ops;
762 init.flags = 0;
763 init.parent_names = parent_names;
764 vc5->clk_mux.init = &init;
765 ret = devm_clk_hw_register(&client->dev, &vc5->clk_mux);
766 if (ret) {
767 dev_err(&client->dev, "unable to register %s\n", init.name);
768 goto err_clk;
769 }
770
771 if (vc5->chip_info->flags & VC5_HAS_PFD_FREQ_DBL) {
772 /* Register frequency doubler */
773 memset(&init, 0, sizeof(init));
774 init.name = vc5_dbl_names[0];
775 init.ops = &vc5_dbl_ops;
776 init.flags = CLK_SET_RATE_PARENT;
777 init.parent_names = vc5_mux_names;
778 init.num_parents = 1;
779 vc5->clk_mul.init = &init;
780 ret = devm_clk_hw_register(&client->dev, &vc5->clk_mul);
781 if (ret) {
782 dev_err(&client->dev, "unable to register %s\n",
783 init.name);
784 goto err_clk;
785 }
786 }
787
788 /* Register PFD */
789 memset(&init, 0, sizeof(init));
790 init.name = vc5_pfd_names[0];
791 init.ops = &vc5_pfd_ops;
792 init.flags = CLK_SET_RATE_PARENT;
793 if (vc5->chip_info->flags & VC5_HAS_PFD_FREQ_DBL)
794 init.parent_names = vc5_dbl_names;
795 else
796 init.parent_names = vc5_mux_names;
797 init.num_parents = 1;
798 vc5->clk_pfd.init = &init;
799 ret = devm_clk_hw_register(&client->dev, &vc5->clk_pfd);
800 if (ret) {
801 dev_err(&client->dev, "unable to register %s\n", init.name);
802 goto err_clk;
803 }
804
805 /* Register PLL */
806 memset(&init, 0, sizeof(init));
807 init.name = vc5_pll_names[0];
808 init.ops = &vc5_pll_ops;
809 init.flags = CLK_SET_RATE_PARENT;
810 init.parent_names = vc5_pfd_names;
811 init.num_parents = 1;
812 vc5->clk_pll.num = 0;
813 vc5->clk_pll.vc5 = vc5;
814 vc5->clk_pll.hw.init = &init;
815 ret = devm_clk_hw_register(&client->dev, &vc5->clk_pll.hw);
816 if (ret) {
817 dev_err(&client->dev, "unable to register %s\n", init.name);
818 goto err_clk;
819 }
820
821 /* Register FODs */
822 for (n = 0; n < vc5->chip_info->clk_fod_cnt; n++) {
823 idx = vc5_map_index_to_output(vc5->chip_info->model, n);
824 memset(&init, 0, sizeof(init));
825 init.name = vc5_fod_names[idx];
826 init.ops = &vc5_fod_ops;
827 init.flags = CLK_SET_RATE_PARENT;
828 init.parent_names = vc5_pll_names;
829 init.num_parents = 1;
830 vc5->clk_fod[n].num = idx;
831 vc5->clk_fod[n].vc5 = vc5;
832 vc5->clk_fod[n].hw.init = &init;
833 ret = devm_clk_hw_register(&client->dev, &vc5->clk_fod[n].hw);
834 if (ret) {
835 dev_err(&client->dev, "unable to register %s\n",
836 init.name);
837 goto err_clk;
838 }
839 }
840
841 /* Register MUX-connected OUT0_I2C_SELB output */
842 memset(&init, 0, sizeof(init));
843 init.name = vc5_clk_out_names[0];
844 init.ops = &vc5_clk_out_ops;
845 init.flags = CLK_SET_RATE_PARENT;
846 init.parent_names = vc5_mux_names;
847 init.num_parents = 1;
848 vc5->clk_out[0].num = idx;
849 vc5->clk_out[0].vc5 = vc5;
850 vc5->clk_out[0].hw.init = &init;
851 ret = devm_clk_hw_register(&client->dev, &vc5->clk_out[0].hw);
852 if (ret) {
853 dev_err(&client->dev, "unable to register %s\n",
854 init.name);
855 goto err_clk;
856 }
857
858 /* Register FOD-connected OUTx outputs */
859 for (n = 1; n < vc5->chip_info->clk_out_cnt; n++) {
860 idx = vc5_map_index_to_output(vc5->chip_info->model, n - 1);
861 parent_names[0] = vc5_fod_names[idx];
862 if (n == 1)
863 parent_names[1] = vc5_mux_names[0];
864 else
865 parent_names[1] = vc5_clk_out_names[n - 1];
866
867 memset(&init, 0, sizeof(init));
868 init.name = vc5_clk_out_names[idx + 1];
869 init.ops = &vc5_clk_out_ops;
870 init.flags = CLK_SET_RATE_PARENT;
871 init.parent_names = parent_names;
872 init.num_parents = 2;
873 vc5->clk_out[n].num = idx;
874 vc5->clk_out[n].vc5 = vc5;
875 vc5->clk_out[n].hw.init = &init;
876 ret = devm_clk_hw_register(&client->dev,
877 &vc5->clk_out[n].hw);
878 if (ret) {
879 dev_err(&client->dev, "unable to register %s\n",
880 init.name);
881 goto err_clk;
882 }
883 }
884
885 ret = of_clk_add_hw_provider(client->dev.of_node, vc5_of_clk_get, vc5);
886 if (ret) {
887 dev_err(&client->dev, "unable to add clk provider\n");
888 goto err_clk;
889 }
890
891 return 0;
892
893 err_clk:
894 if (vc5->chip_info->flags & VC5_HAS_INTERNAL_XTAL)
895 clk_unregister_fixed_rate(vc5->pin_xin);
896 return ret;
897 }
898
vc5_remove(struct i2c_client * client)899 static int vc5_remove(struct i2c_client *client)
900 {
901 struct vc5_driver_data *vc5 = i2c_get_clientdata(client);
902
903 of_clk_del_provider(client->dev.of_node);
904
905 if (vc5->chip_info->flags & VC5_HAS_INTERNAL_XTAL)
906 clk_unregister_fixed_rate(vc5->pin_xin);
907
908 return 0;
909 }
910
911 static const struct vc5_chip_info idt_5p49v5923_info = {
912 .model = IDT_VC5_5P49V5923,
913 .clk_fod_cnt = 2,
914 .clk_out_cnt = 3,
915 .flags = 0,
916 };
917
918 static const struct vc5_chip_info idt_5p49v5925_info = {
919 .model = IDT_VC5_5P49V5925,
920 .clk_fod_cnt = 4,
921 .clk_out_cnt = 5,
922 .flags = 0,
923 };
924
925 static const struct vc5_chip_info idt_5p49v5933_info = {
926 .model = IDT_VC5_5P49V5933,
927 .clk_fod_cnt = 2,
928 .clk_out_cnt = 3,
929 .flags = VC5_HAS_INTERNAL_XTAL,
930 };
931
932 static const struct vc5_chip_info idt_5p49v5935_info = {
933 .model = IDT_VC5_5P49V5935,
934 .clk_fod_cnt = 4,
935 .clk_out_cnt = 5,
936 .flags = VC5_HAS_INTERNAL_XTAL,
937 };
938
939 static const struct vc5_chip_info idt_5p49v6901_info = {
940 .model = IDT_VC6_5P49V6901,
941 .clk_fod_cnt = 4,
942 .clk_out_cnt = 5,
943 .flags = VC5_HAS_PFD_FREQ_DBL,
944 };
945
946 static const struct i2c_device_id vc5_id[] = {
947 { "5p49v5923", .driver_data = IDT_VC5_5P49V5923 },
948 { "5p49v5925", .driver_data = IDT_VC5_5P49V5925 },
949 { "5p49v5933", .driver_data = IDT_VC5_5P49V5933 },
950 { "5p49v5935", .driver_data = IDT_VC5_5P49V5935 },
951 { "5p49v6901", .driver_data = IDT_VC6_5P49V6901 },
952 { }
953 };
954 MODULE_DEVICE_TABLE(i2c, vc5_id);
955
956 static const struct of_device_id clk_vc5_of_match[] = {
957 { .compatible = "idt,5p49v5923", .data = &idt_5p49v5923_info },
958 { .compatible = "idt,5p49v5925", .data = &idt_5p49v5925_info },
959 { .compatible = "idt,5p49v5933", .data = &idt_5p49v5933_info },
960 { .compatible = "idt,5p49v5935", .data = &idt_5p49v5935_info },
961 { .compatible = "idt,5p49v6901", .data = &idt_5p49v6901_info },
962 { },
963 };
964 MODULE_DEVICE_TABLE(of, clk_vc5_of_match);
965
966 static struct i2c_driver vc5_driver = {
967 .driver = {
968 .name = "vc5",
969 .of_match_table = clk_vc5_of_match,
970 },
971 .probe = vc5_probe,
972 .remove = vc5_remove,
973 .id_table = vc5_id,
974 };
975 module_i2c_driver(vc5_driver);
976
977 MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
978 MODULE_DESCRIPTION("IDT VersaClock 5 driver");
979 MODULE_LICENSE("GPL");
980