xref: /openbmc/linux/drivers/clk/clk-versaclock5.c (revision b830f94f)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Driver for IDT Versaclock 5
4  *
5  * Copyright (C) 2017 Marek Vasut <marek.vasut@gmail.com>
6  */
7 
8 /*
9  * Possible optimizations:
10  * - Use spread spectrum
11  * - Use integer divider in FOD if applicable
12  */
13 
14 #include <linux/clk.h>
15 #include <linux/clk-provider.h>
16 #include <linux/delay.h>
17 #include <linux/i2c.h>
18 #include <linux/interrupt.h>
19 #include <linux/mod_devicetable.h>
20 #include <linux/module.h>
21 #include <linux/of.h>
22 #include <linux/of_platform.h>
23 #include <linux/rational.h>
24 #include <linux/regmap.h>
25 #include <linux/slab.h>
26 
27 /* VersaClock5 registers */
28 #define VC5_OTP_CONTROL				0x00
29 
30 /* Factory-reserved register block */
31 #define VC5_RSVD_DEVICE_ID			0x01
32 #define VC5_RSVD_ADC_GAIN_7_0			0x02
33 #define VC5_RSVD_ADC_GAIN_15_8			0x03
34 #define VC5_RSVD_ADC_OFFSET_7_0			0x04
35 #define VC5_RSVD_ADC_OFFSET_15_8		0x05
36 #define VC5_RSVD_TEMPY				0x06
37 #define VC5_RSVD_OFFSET_TBIN			0x07
38 #define VC5_RSVD_GAIN				0x08
39 #define VC5_RSVD_TEST_NP			0x09
40 #define VC5_RSVD_UNUSED				0x0a
41 #define VC5_RSVD_BANDGAP_TRIM_UP		0x0b
42 #define VC5_RSVD_BANDGAP_TRIM_DN		0x0c
43 #define VC5_RSVD_CLK_R_12_CLK_AMP_4		0x0d
44 #define VC5_RSVD_CLK_R_34_CLK_AMP_4		0x0e
45 #define VC5_RSVD_CLK_AMP_123			0x0f
46 
47 /* Configuration register block */
48 #define VC5_PRIM_SRC_SHDN			0x10
49 #define VC5_PRIM_SRC_SHDN_EN_XTAL		BIT(7)
50 #define VC5_PRIM_SRC_SHDN_EN_CLKIN		BIT(6)
51 #define VC5_PRIM_SRC_SHDN_EN_DOUBLE_XTAL_FREQ	BIT(3)
52 #define VC5_PRIM_SRC_SHDN_SP			BIT(1)
53 #define VC5_PRIM_SRC_SHDN_EN_GBL_SHDN		BIT(0)
54 
55 #define VC5_VCO_BAND				0x11
56 #define VC5_XTAL_X1_LOAD_CAP			0x12
57 #define VC5_XTAL_X2_LOAD_CAP			0x13
58 #define VC5_REF_DIVIDER				0x15
59 #define VC5_REF_DIVIDER_SEL_PREDIV2		BIT(7)
60 #define VC5_REF_DIVIDER_REF_DIV(n)		((n) & 0x3f)
61 
62 #define VC5_VCO_CTRL_AND_PREDIV			0x16
63 #define VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV	BIT(7)
64 
65 #define VC5_FEEDBACK_INT_DIV			0x17
66 #define VC5_FEEDBACK_INT_DIV_BITS		0x18
67 #define VC5_FEEDBACK_FRAC_DIV(n)		(0x19 + (n))
68 #define VC5_RC_CONTROL0				0x1e
69 #define VC5_RC_CONTROL1				0x1f
70 /* Register 0x20 is factory reserved */
71 
72 /* Output divider control for divider 1,2,3,4 */
73 #define VC5_OUT_DIV_CONTROL(idx)	(0x21 + ((idx) * 0x10))
74 #define VC5_OUT_DIV_CONTROL_RESET	BIT(7)
75 #define VC5_OUT_DIV_CONTROL_SELB_NORM	BIT(3)
76 #define VC5_OUT_DIV_CONTROL_SEL_EXT	BIT(2)
77 #define VC5_OUT_DIV_CONTROL_INT_MODE	BIT(1)
78 #define VC5_OUT_DIV_CONTROL_EN_FOD	BIT(0)
79 
80 #define VC5_OUT_DIV_FRAC(idx, n)	(0x22 + ((idx) * 0x10) + (n))
81 #define VC5_OUT_DIV_FRAC4_OD_SCEE	BIT(1)
82 
83 #define VC5_OUT_DIV_STEP_SPREAD(idx, n)	(0x26 + ((idx) * 0x10) + (n))
84 #define VC5_OUT_DIV_SPREAD_MOD(idx, n)	(0x29 + ((idx) * 0x10) + (n))
85 #define VC5_OUT_DIV_SKEW_INT(idx, n)	(0x2b + ((idx) * 0x10) + (n))
86 #define VC5_OUT_DIV_INT(idx, n)		(0x2d + ((idx) * 0x10) + (n))
87 #define VC5_OUT_DIV_SKEW_FRAC(idx)	(0x2f + ((idx) * 0x10))
88 /* Registers 0x30, 0x40, 0x50 are factory reserved */
89 
90 /* Clock control register for clock 1,2 */
91 #define VC5_CLK_OUTPUT_CFG(idx, n)	(0x60 + ((idx) * 0x2) + (n))
92 #define VC5_CLK_OUTPUT_CFG1_EN_CLKBUF	BIT(0)
93 
94 #define VC5_CLK_OE_SHDN				0x68
95 #define VC5_CLK_OS_SHDN				0x69
96 
97 #define VC5_GLOBAL_REGISTER			0x76
98 #define VC5_GLOBAL_REGISTER_GLOBAL_RESET	BIT(5)
99 
100 /* PLL/VCO runs between 2.5 GHz and 3.0 GHz */
101 #define VC5_PLL_VCO_MIN				2500000000UL
102 #define VC5_PLL_VCO_MAX				3000000000UL
103 
104 /* VC5 Input mux settings */
105 #define VC5_MUX_IN_XIN		BIT(0)
106 #define VC5_MUX_IN_CLKIN	BIT(1)
107 
108 /* Maximum number of clk_out supported by this driver */
109 #define VC5_MAX_CLK_OUT_NUM	5
110 
111 /* Maximum number of FODs supported by this driver */
112 #define VC5_MAX_FOD_NUM	4
113 
114 /* flags to describe chip features */
115 /* chip has built-in oscilator */
116 #define VC5_HAS_INTERNAL_XTAL	BIT(0)
117 /* chip has PFD requency doubler */
118 #define VC5_HAS_PFD_FREQ_DBL	BIT(1)
119 
120 /* Supported IDT VC5 models. */
121 enum vc5_model {
122 	IDT_VC5_5P49V5923,
123 	IDT_VC5_5P49V5925,
124 	IDT_VC5_5P49V5933,
125 	IDT_VC5_5P49V5935,
126 	IDT_VC6_5P49V6901,
127 };
128 
129 /* Structure to describe features of a particular VC5 model */
130 struct vc5_chip_info {
131 	const enum vc5_model	model;
132 	const unsigned int	clk_fod_cnt;
133 	const unsigned int	clk_out_cnt;
134 	const u32		flags;
135 };
136 
137 struct vc5_driver_data;
138 
139 struct vc5_hw_data {
140 	struct clk_hw		hw;
141 	struct vc5_driver_data	*vc5;
142 	u32			div_int;
143 	u32			div_frc;
144 	unsigned int		num;
145 };
146 
147 struct vc5_driver_data {
148 	struct i2c_client	*client;
149 	struct regmap		*regmap;
150 	const struct vc5_chip_info	*chip_info;
151 
152 	struct clk		*pin_xin;
153 	struct clk		*pin_clkin;
154 	unsigned char		clk_mux_ins;
155 	struct clk_hw		clk_mux;
156 	struct clk_hw		clk_mul;
157 	struct clk_hw		clk_pfd;
158 	struct vc5_hw_data	clk_pll;
159 	struct vc5_hw_data	clk_fod[VC5_MAX_FOD_NUM];
160 	struct vc5_hw_data	clk_out[VC5_MAX_CLK_OUT_NUM];
161 };
162 
163 static const char * const vc5_mux_names[] = {
164 	"mux"
165 };
166 
167 static const char * const vc5_dbl_names[] = {
168 	"dbl"
169 };
170 
171 static const char * const vc5_pfd_names[] = {
172 	"pfd"
173 };
174 
175 static const char * const vc5_pll_names[] = {
176 	"pll"
177 };
178 
179 static const char * const vc5_fod_names[] = {
180 	"fod0", "fod1", "fod2", "fod3",
181 };
182 
183 static const char * const vc5_clk_out_names[] = {
184 	"out0_sel_i2cb", "out1", "out2", "out3", "out4",
185 };
186 
187 /*
188  * VersaClock5 i2c regmap
189  */
190 static bool vc5_regmap_is_writeable(struct device *dev, unsigned int reg)
191 {
192 	/* Factory reserved regs, make them read-only */
193 	if (reg <= 0xf)
194 		return false;
195 
196 	/* Factory reserved regs, make them read-only */
197 	if (reg == 0x14 || reg == 0x1c || reg == 0x1d)
198 		return false;
199 
200 	return true;
201 }
202 
203 static const struct regmap_config vc5_regmap_config = {
204 	.reg_bits = 8,
205 	.val_bits = 8,
206 	.cache_type = REGCACHE_RBTREE,
207 	.max_register = 0x76,
208 	.writeable_reg = vc5_regmap_is_writeable,
209 };
210 
211 /*
212  * VersaClock5 input multiplexer between XTAL and CLKIN divider
213  */
214 static unsigned char vc5_mux_get_parent(struct clk_hw *hw)
215 {
216 	struct vc5_driver_data *vc5 =
217 		container_of(hw, struct vc5_driver_data, clk_mux);
218 	const u8 mask = VC5_PRIM_SRC_SHDN_EN_XTAL | VC5_PRIM_SRC_SHDN_EN_CLKIN;
219 	unsigned int src;
220 
221 	regmap_read(vc5->regmap, VC5_PRIM_SRC_SHDN, &src);
222 	src &= mask;
223 
224 	if (src == VC5_PRIM_SRC_SHDN_EN_XTAL)
225 		return 0;
226 
227 	if (src == VC5_PRIM_SRC_SHDN_EN_CLKIN)
228 		return 1;
229 
230 	dev_warn(&vc5->client->dev,
231 		 "Invalid clock input configuration (%02x)\n", src);
232 	return 0;
233 }
234 
235 static int vc5_mux_set_parent(struct clk_hw *hw, u8 index)
236 {
237 	struct vc5_driver_data *vc5 =
238 		container_of(hw, struct vc5_driver_data, clk_mux);
239 	const u8 mask = VC5_PRIM_SRC_SHDN_EN_XTAL | VC5_PRIM_SRC_SHDN_EN_CLKIN;
240 	u8 src;
241 
242 	if ((index > 1) || !vc5->clk_mux_ins)
243 		return -EINVAL;
244 
245 	if (vc5->clk_mux_ins == (VC5_MUX_IN_CLKIN | VC5_MUX_IN_XIN)) {
246 		if (index == 0)
247 			src = VC5_PRIM_SRC_SHDN_EN_XTAL;
248 		if (index == 1)
249 			src = VC5_PRIM_SRC_SHDN_EN_CLKIN;
250 	} else {
251 		if (index != 0)
252 			return -EINVAL;
253 
254 		if (vc5->clk_mux_ins == VC5_MUX_IN_XIN)
255 			src = VC5_PRIM_SRC_SHDN_EN_XTAL;
256 		else if (vc5->clk_mux_ins == VC5_MUX_IN_CLKIN)
257 			src = VC5_PRIM_SRC_SHDN_EN_CLKIN;
258 		else /* Invalid; should have been caught by vc5_probe() */
259 			return -EINVAL;
260 	}
261 
262 	return regmap_update_bits(vc5->regmap, VC5_PRIM_SRC_SHDN, mask, src);
263 }
264 
265 static const struct clk_ops vc5_mux_ops = {
266 	.set_parent	= vc5_mux_set_parent,
267 	.get_parent	= vc5_mux_get_parent,
268 };
269 
270 static unsigned long vc5_dbl_recalc_rate(struct clk_hw *hw,
271 					 unsigned long parent_rate)
272 {
273 	struct vc5_driver_data *vc5 =
274 		container_of(hw, struct vc5_driver_data, clk_mul);
275 	unsigned int premul;
276 
277 	regmap_read(vc5->regmap, VC5_PRIM_SRC_SHDN, &premul);
278 	if (premul & VC5_PRIM_SRC_SHDN_EN_DOUBLE_XTAL_FREQ)
279 		parent_rate *= 2;
280 
281 	return parent_rate;
282 }
283 
284 static long vc5_dbl_round_rate(struct clk_hw *hw, unsigned long rate,
285 			       unsigned long *parent_rate)
286 {
287 	if ((*parent_rate == rate) || ((*parent_rate * 2) == rate))
288 		return rate;
289 	else
290 		return -EINVAL;
291 }
292 
293 static int vc5_dbl_set_rate(struct clk_hw *hw, unsigned long rate,
294 			    unsigned long parent_rate)
295 {
296 	struct vc5_driver_data *vc5 =
297 		container_of(hw, struct vc5_driver_data, clk_mul);
298 	u32 mask;
299 
300 	if ((parent_rate * 2) == rate)
301 		mask = VC5_PRIM_SRC_SHDN_EN_DOUBLE_XTAL_FREQ;
302 	else
303 		mask = 0;
304 
305 	regmap_update_bits(vc5->regmap, VC5_PRIM_SRC_SHDN,
306 			   VC5_PRIM_SRC_SHDN_EN_DOUBLE_XTAL_FREQ,
307 			   mask);
308 
309 	return 0;
310 }
311 
312 static const struct clk_ops vc5_dbl_ops = {
313 	.recalc_rate	= vc5_dbl_recalc_rate,
314 	.round_rate	= vc5_dbl_round_rate,
315 	.set_rate	= vc5_dbl_set_rate,
316 };
317 
318 static unsigned long vc5_pfd_recalc_rate(struct clk_hw *hw,
319 					 unsigned long parent_rate)
320 {
321 	struct vc5_driver_data *vc5 =
322 		container_of(hw, struct vc5_driver_data, clk_pfd);
323 	unsigned int prediv, div;
324 
325 	regmap_read(vc5->regmap, VC5_VCO_CTRL_AND_PREDIV, &prediv);
326 
327 	/* The bypass_prediv is set, PLL fed from Ref_in directly. */
328 	if (prediv & VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV)
329 		return parent_rate;
330 
331 	regmap_read(vc5->regmap, VC5_REF_DIVIDER, &div);
332 
333 	/* The Sel_prediv2 is set, PLL fed from prediv2 (Ref_in / 2) */
334 	if (div & VC5_REF_DIVIDER_SEL_PREDIV2)
335 		return parent_rate / 2;
336 	else
337 		return parent_rate / VC5_REF_DIVIDER_REF_DIV(div);
338 }
339 
340 static long vc5_pfd_round_rate(struct clk_hw *hw, unsigned long rate,
341 			       unsigned long *parent_rate)
342 {
343 	unsigned long idiv;
344 
345 	/* PLL cannot operate with input clock above 50 MHz. */
346 	if (rate > 50000000)
347 		return -EINVAL;
348 
349 	/* CLKIN within range of PLL input, feed directly to PLL. */
350 	if (*parent_rate <= 50000000)
351 		return *parent_rate;
352 
353 	idiv = DIV_ROUND_UP(*parent_rate, rate);
354 	if (idiv > 127)
355 		return -EINVAL;
356 
357 	return *parent_rate / idiv;
358 }
359 
360 static int vc5_pfd_set_rate(struct clk_hw *hw, unsigned long rate,
361 			    unsigned long parent_rate)
362 {
363 	struct vc5_driver_data *vc5 =
364 		container_of(hw, struct vc5_driver_data, clk_pfd);
365 	unsigned long idiv;
366 	u8 div;
367 
368 	/* CLKIN within range of PLL input, feed directly to PLL. */
369 	if (parent_rate <= 50000000) {
370 		regmap_update_bits(vc5->regmap, VC5_VCO_CTRL_AND_PREDIV,
371 				   VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV,
372 				   VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV);
373 		regmap_update_bits(vc5->regmap, VC5_REF_DIVIDER, 0xff, 0x00);
374 		return 0;
375 	}
376 
377 	idiv = DIV_ROUND_UP(parent_rate, rate);
378 
379 	/* We have dedicated div-2 predivider. */
380 	if (idiv == 2)
381 		div = VC5_REF_DIVIDER_SEL_PREDIV2;
382 	else
383 		div = VC5_REF_DIVIDER_REF_DIV(idiv);
384 
385 	regmap_update_bits(vc5->regmap, VC5_REF_DIVIDER, 0xff, div);
386 	regmap_update_bits(vc5->regmap, VC5_VCO_CTRL_AND_PREDIV,
387 			   VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV, 0);
388 
389 	return 0;
390 }
391 
392 static const struct clk_ops vc5_pfd_ops = {
393 	.recalc_rate	= vc5_pfd_recalc_rate,
394 	.round_rate	= vc5_pfd_round_rate,
395 	.set_rate	= vc5_pfd_set_rate,
396 };
397 
398 /*
399  * VersaClock5 PLL/VCO
400  */
401 static unsigned long vc5_pll_recalc_rate(struct clk_hw *hw,
402 					 unsigned long parent_rate)
403 {
404 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
405 	struct vc5_driver_data *vc5 = hwdata->vc5;
406 	u32 div_int, div_frc;
407 	u8 fb[5];
408 
409 	regmap_bulk_read(vc5->regmap, VC5_FEEDBACK_INT_DIV, fb, 5);
410 
411 	div_int = (fb[0] << 4) | (fb[1] >> 4);
412 	div_frc = (fb[2] << 16) | (fb[3] << 8) | fb[4];
413 
414 	/* The PLL divider has 12 integer bits and 24 fractional bits */
415 	return (parent_rate * div_int) + ((parent_rate * div_frc) >> 24);
416 }
417 
418 static long vc5_pll_round_rate(struct clk_hw *hw, unsigned long rate,
419 			       unsigned long *parent_rate)
420 {
421 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
422 	u32 div_int;
423 	u64 div_frc;
424 
425 	if (rate < VC5_PLL_VCO_MIN)
426 		rate = VC5_PLL_VCO_MIN;
427 	if (rate > VC5_PLL_VCO_MAX)
428 		rate = VC5_PLL_VCO_MAX;
429 
430 	/* Determine integer part, which is 12 bit wide */
431 	div_int = rate / *parent_rate;
432 	if (div_int > 0xfff)
433 		rate = *parent_rate * 0xfff;
434 
435 	/* Determine best fractional part, which is 24 bit wide */
436 	div_frc = rate % *parent_rate;
437 	div_frc *= BIT(24) - 1;
438 	do_div(div_frc, *parent_rate);
439 
440 	hwdata->div_int = div_int;
441 	hwdata->div_frc = (u32)div_frc;
442 
443 	return (*parent_rate * div_int) + ((*parent_rate * div_frc) >> 24);
444 }
445 
446 static int vc5_pll_set_rate(struct clk_hw *hw, unsigned long rate,
447 			    unsigned long parent_rate)
448 {
449 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
450 	struct vc5_driver_data *vc5 = hwdata->vc5;
451 	u8 fb[5];
452 
453 	fb[0] = hwdata->div_int >> 4;
454 	fb[1] = hwdata->div_int << 4;
455 	fb[2] = hwdata->div_frc >> 16;
456 	fb[3] = hwdata->div_frc >> 8;
457 	fb[4] = hwdata->div_frc;
458 
459 	return regmap_bulk_write(vc5->regmap, VC5_FEEDBACK_INT_DIV, fb, 5);
460 }
461 
462 static const struct clk_ops vc5_pll_ops = {
463 	.recalc_rate	= vc5_pll_recalc_rate,
464 	.round_rate	= vc5_pll_round_rate,
465 	.set_rate	= vc5_pll_set_rate,
466 };
467 
468 static unsigned long vc5_fod_recalc_rate(struct clk_hw *hw,
469 					 unsigned long parent_rate)
470 {
471 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
472 	struct vc5_driver_data *vc5 = hwdata->vc5;
473 	/* VCO frequency is divided by two before entering FOD */
474 	u32 f_in = parent_rate / 2;
475 	u32 div_int, div_frc;
476 	u8 od_int[2];
477 	u8 od_frc[4];
478 
479 	regmap_bulk_read(vc5->regmap, VC5_OUT_DIV_INT(hwdata->num, 0),
480 			 od_int, 2);
481 	regmap_bulk_read(vc5->regmap, VC5_OUT_DIV_FRAC(hwdata->num, 0),
482 			 od_frc, 4);
483 
484 	div_int = (od_int[0] << 4) | (od_int[1] >> 4);
485 	div_frc = (od_frc[0] << 22) | (od_frc[1] << 14) |
486 		  (od_frc[2] << 6) | (od_frc[3] >> 2);
487 
488 	/* Avoid division by zero if the output is not configured. */
489 	if (div_int == 0 && div_frc == 0)
490 		return 0;
491 
492 	/* The PLL divider has 12 integer bits and 30 fractional bits */
493 	return div64_u64((u64)f_in << 24ULL, ((u64)div_int << 24ULL) + div_frc);
494 }
495 
496 static long vc5_fod_round_rate(struct clk_hw *hw, unsigned long rate,
497 			       unsigned long *parent_rate)
498 {
499 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
500 	/* VCO frequency is divided by two before entering FOD */
501 	u32 f_in = *parent_rate / 2;
502 	u32 div_int;
503 	u64 div_frc;
504 
505 	/* Determine integer part, which is 12 bit wide */
506 	div_int = f_in / rate;
507 	/*
508 	 * WARNING: The clock chip does not output signal if the integer part
509 	 *          of the divider is 0xfff and fractional part is non-zero.
510 	 *          Clamp the divider at 0xffe to keep the code simple.
511 	 */
512 	if (div_int > 0xffe) {
513 		div_int = 0xffe;
514 		rate = f_in / div_int;
515 	}
516 
517 	/* Determine best fractional part, which is 30 bit wide */
518 	div_frc = f_in % rate;
519 	div_frc <<= 24;
520 	do_div(div_frc, rate);
521 
522 	hwdata->div_int = div_int;
523 	hwdata->div_frc = (u32)div_frc;
524 
525 	return div64_u64((u64)f_in << 24ULL, ((u64)div_int << 24ULL) + div_frc);
526 }
527 
528 static int vc5_fod_set_rate(struct clk_hw *hw, unsigned long rate,
529 			    unsigned long parent_rate)
530 {
531 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
532 	struct vc5_driver_data *vc5 = hwdata->vc5;
533 	u8 data[14] = {
534 		hwdata->div_frc >> 22, hwdata->div_frc >> 14,
535 		hwdata->div_frc >> 6, hwdata->div_frc << 2,
536 		0, 0, 0, 0, 0,
537 		0, 0,
538 		hwdata->div_int >> 4, hwdata->div_int << 4,
539 		0
540 	};
541 
542 	regmap_bulk_write(vc5->regmap, VC5_OUT_DIV_FRAC(hwdata->num, 0),
543 			  data, 14);
544 
545 	/*
546 	 * Toggle magic bit in undocumented register for unknown reason.
547 	 * This is what the IDT timing commander tool does and the chip
548 	 * datasheet somewhat implies this is needed, but the register
549 	 * and the bit is not documented.
550 	 */
551 	regmap_update_bits(vc5->regmap, VC5_GLOBAL_REGISTER,
552 			   VC5_GLOBAL_REGISTER_GLOBAL_RESET, 0);
553 	regmap_update_bits(vc5->regmap, VC5_GLOBAL_REGISTER,
554 			   VC5_GLOBAL_REGISTER_GLOBAL_RESET,
555 			   VC5_GLOBAL_REGISTER_GLOBAL_RESET);
556 	return 0;
557 }
558 
559 static const struct clk_ops vc5_fod_ops = {
560 	.recalc_rate	= vc5_fod_recalc_rate,
561 	.round_rate	= vc5_fod_round_rate,
562 	.set_rate	= vc5_fod_set_rate,
563 };
564 
565 static int vc5_clk_out_prepare(struct clk_hw *hw)
566 {
567 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
568 	struct vc5_driver_data *vc5 = hwdata->vc5;
569 	const u8 mask = VC5_OUT_DIV_CONTROL_SELB_NORM |
570 			VC5_OUT_DIV_CONTROL_SEL_EXT |
571 			VC5_OUT_DIV_CONTROL_EN_FOD;
572 	unsigned int src;
573 	int ret;
574 
575 	/*
576 	 * If the input mux is disabled, enable it first and
577 	 * select source from matching FOD.
578 	 */
579 	regmap_read(vc5->regmap, VC5_OUT_DIV_CONTROL(hwdata->num), &src);
580 	if ((src & mask) == 0) {
581 		src = VC5_OUT_DIV_CONTROL_RESET | VC5_OUT_DIV_CONTROL_EN_FOD;
582 		ret = regmap_update_bits(vc5->regmap,
583 					 VC5_OUT_DIV_CONTROL(hwdata->num),
584 					 mask | VC5_OUT_DIV_CONTROL_RESET, src);
585 		if (ret)
586 			return ret;
587 	}
588 
589 	/* Enable the clock buffer */
590 	regmap_update_bits(vc5->regmap, VC5_CLK_OUTPUT_CFG(hwdata->num, 1),
591 			   VC5_CLK_OUTPUT_CFG1_EN_CLKBUF,
592 			   VC5_CLK_OUTPUT_CFG1_EN_CLKBUF);
593 	return 0;
594 }
595 
596 static void vc5_clk_out_unprepare(struct clk_hw *hw)
597 {
598 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
599 	struct vc5_driver_data *vc5 = hwdata->vc5;
600 
601 	/* Disable the clock buffer */
602 	regmap_update_bits(vc5->regmap, VC5_CLK_OUTPUT_CFG(hwdata->num, 1),
603 			   VC5_CLK_OUTPUT_CFG1_EN_CLKBUF, 0);
604 }
605 
606 static unsigned char vc5_clk_out_get_parent(struct clk_hw *hw)
607 {
608 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
609 	struct vc5_driver_data *vc5 = hwdata->vc5;
610 	const u8 mask = VC5_OUT_DIV_CONTROL_SELB_NORM |
611 			VC5_OUT_DIV_CONTROL_SEL_EXT |
612 			VC5_OUT_DIV_CONTROL_EN_FOD;
613 	const u8 fodclkmask = VC5_OUT_DIV_CONTROL_SELB_NORM |
614 			      VC5_OUT_DIV_CONTROL_EN_FOD;
615 	const u8 extclk = VC5_OUT_DIV_CONTROL_SELB_NORM |
616 			  VC5_OUT_DIV_CONTROL_SEL_EXT;
617 	unsigned int src;
618 
619 	regmap_read(vc5->regmap, VC5_OUT_DIV_CONTROL(hwdata->num), &src);
620 	src &= mask;
621 
622 	if (src == 0)	/* Input mux set to DISABLED */
623 		return 0;
624 
625 	if ((src & fodclkmask) == VC5_OUT_DIV_CONTROL_EN_FOD)
626 		return 0;
627 
628 	if (src == extclk)
629 		return 1;
630 
631 	dev_warn(&vc5->client->dev,
632 		 "Invalid clock output configuration (%02x)\n", src);
633 	return 0;
634 }
635 
636 static int vc5_clk_out_set_parent(struct clk_hw *hw, u8 index)
637 {
638 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
639 	struct vc5_driver_data *vc5 = hwdata->vc5;
640 	const u8 mask = VC5_OUT_DIV_CONTROL_RESET |
641 			VC5_OUT_DIV_CONTROL_SELB_NORM |
642 			VC5_OUT_DIV_CONTROL_SEL_EXT |
643 			VC5_OUT_DIV_CONTROL_EN_FOD;
644 	const u8 extclk = VC5_OUT_DIV_CONTROL_SELB_NORM |
645 			  VC5_OUT_DIV_CONTROL_SEL_EXT;
646 	u8 src = VC5_OUT_DIV_CONTROL_RESET;
647 
648 	if (index == 0)
649 		src |= VC5_OUT_DIV_CONTROL_EN_FOD;
650 	else
651 		src |= extclk;
652 
653 	return regmap_update_bits(vc5->regmap, VC5_OUT_DIV_CONTROL(hwdata->num),
654 				  mask, src);
655 }
656 
657 static const struct clk_ops vc5_clk_out_ops = {
658 	.prepare	= vc5_clk_out_prepare,
659 	.unprepare	= vc5_clk_out_unprepare,
660 	.set_parent	= vc5_clk_out_set_parent,
661 	.get_parent	= vc5_clk_out_get_parent,
662 };
663 
664 static struct clk_hw *vc5_of_clk_get(struct of_phandle_args *clkspec,
665 				     void *data)
666 {
667 	struct vc5_driver_data *vc5 = data;
668 	unsigned int idx = clkspec->args[0];
669 
670 	if (idx >= vc5->chip_info->clk_out_cnt)
671 		return ERR_PTR(-EINVAL);
672 
673 	return &vc5->clk_out[idx].hw;
674 }
675 
676 static int vc5_map_index_to_output(const enum vc5_model model,
677 				   const unsigned int n)
678 {
679 	switch (model) {
680 	case IDT_VC5_5P49V5933:
681 		return (n == 0) ? 0 : 3;
682 	case IDT_VC5_5P49V5923:
683 	case IDT_VC5_5P49V5925:
684 	case IDT_VC5_5P49V5935:
685 	case IDT_VC6_5P49V6901:
686 	default:
687 		return n;
688 	}
689 }
690 
691 static const struct of_device_id clk_vc5_of_match[];
692 
693 static int vc5_probe(struct i2c_client *client,
694 		     const struct i2c_device_id *id)
695 {
696 	struct vc5_driver_data *vc5;
697 	struct clk_init_data init;
698 	const char *parent_names[2];
699 	unsigned int n, idx = 0;
700 	int ret;
701 
702 	vc5 = devm_kzalloc(&client->dev, sizeof(*vc5), GFP_KERNEL);
703 	if (vc5 == NULL)
704 		return -ENOMEM;
705 
706 	i2c_set_clientdata(client, vc5);
707 	vc5->client = client;
708 	vc5->chip_info = of_device_get_match_data(&client->dev);
709 
710 	vc5->pin_xin = devm_clk_get(&client->dev, "xin");
711 	if (PTR_ERR(vc5->pin_xin) == -EPROBE_DEFER)
712 		return -EPROBE_DEFER;
713 
714 	vc5->pin_clkin = devm_clk_get(&client->dev, "clkin");
715 	if (PTR_ERR(vc5->pin_clkin) == -EPROBE_DEFER)
716 		return -EPROBE_DEFER;
717 
718 	vc5->regmap = devm_regmap_init_i2c(client, &vc5_regmap_config);
719 	if (IS_ERR(vc5->regmap)) {
720 		dev_err(&client->dev, "failed to allocate register map\n");
721 		return PTR_ERR(vc5->regmap);
722 	}
723 
724 	/* Register clock input mux */
725 	memset(&init, 0, sizeof(init));
726 
727 	if (!IS_ERR(vc5->pin_xin)) {
728 		vc5->clk_mux_ins |= VC5_MUX_IN_XIN;
729 		parent_names[init.num_parents++] = __clk_get_name(vc5->pin_xin);
730 	} else if (vc5->chip_info->flags & VC5_HAS_INTERNAL_XTAL) {
731 		vc5->pin_xin = clk_register_fixed_rate(&client->dev,
732 						       "internal-xtal", NULL,
733 						       0, 25000000);
734 		if (IS_ERR(vc5->pin_xin))
735 			return PTR_ERR(vc5->pin_xin);
736 		vc5->clk_mux_ins |= VC5_MUX_IN_XIN;
737 		parent_names[init.num_parents++] = __clk_get_name(vc5->pin_xin);
738 	}
739 
740 	if (!IS_ERR(vc5->pin_clkin)) {
741 		vc5->clk_mux_ins |= VC5_MUX_IN_CLKIN;
742 		parent_names[init.num_parents++] =
743 			__clk_get_name(vc5->pin_clkin);
744 	}
745 
746 	if (!init.num_parents) {
747 		dev_err(&client->dev, "no input clock specified!\n");
748 		return -EINVAL;
749 	}
750 
751 	init.name = vc5_mux_names[0];
752 	init.ops = &vc5_mux_ops;
753 	init.flags = 0;
754 	init.parent_names = parent_names;
755 	vc5->clk_mux.init = &init;
756 	ret = devm_clk_hw_register(&client->dev, &vc5->clk_mux);
757 	if (ret) {
758 		dev_err(&client->dev, "unable to register %s\n", init.name);
759 		goto err_clk;
760 	}
761 
762 	if (vc5->chip_info->flags & VC5_HAS_PFD_FREQ_DBL) {
763 		/* Register frequency doubler */
764 		memset(&init, 0, sizeof(init));
765 		init.name = vc5_dbl_names[0];
766 		init.ops = &vc5_dbl_ops;
767 		init.flags = CLK_SET_RATE_PARENT;
768 		init.parent_names = vc5_mux_names;
769 		init.num_parents = 1;
770 		vc5->clk_mul.init = &init;
771 		ret = devm_clk_hw_register(&client->dev, &vc5->clk_mul);
772 		if (ret) {
773 			dev_err(&client->dev, "unable to register %s\n",
774 				init.name);
775 			goto err_clk;
776 		}
777 	}
778 
779 	/* Register PFD */
780 	memset(&init, 0, sizeof(init));
781 	init.name = vc5_pfd_names[0];
782 	init.ops = &vc5_pfd_ops;
783 	init.flags = CLK_SET_RATE_PARENT;
784 	if (vc5->chip_info->flags & VC5_HAS_PFD_FREQ_DBL)
785 		init.parent_names = vc5_dbl_names;
786 	else
787 		init.parent_names = vc5_mux_names;
788 	init.num_parents = 1;
789 	vc5->clk_pfd.init = &init;
790 	ret = devm_clk_hw_register(&client->dev, &vc5->clk_pfd);
791 	if (ret) {
792 		dev_err(&client->dev, "unable to register %s\n", init.name);
793 		goto err_clk;
794 	}
795 
796 	/* Register PLL */
797 	memset(&init, 0, sizeof(init));
798 	init.name = vc5_pll_names[0];
799 	init.ops = &vc5_pll_ops;
800 	init.flags = CLK_SET_RATE_PARENT;
801 	init.parent_names = vc5_pfd_names;
802 	init.num_parents = 1;
803 	vc5->clk_pll.num = 0;
804 	vc5->clk_pll.vc5 = vc5;
805 	vc5->clk_pll.hw.init = &init;
806 	ret = devm_clk_hw_register(&client->dev, &vc5->clk_pll.hw);
807 	if (ret) {
808 		dev_err(&client->dev, "unable to register %s\n", init.name);
809 		goto err_clk;
810 	}
811 
812 	/* Register FODs */
813 	for (n = 0; n < vc5->chip_info->clk_fod_cnt; n++) {
814 		idx = vc5_map_index_to_output(vc5->chip_info->model, n);
815 		memset(&init, 0, sizeof(init));
816 		init.name = vc5_fod_names[idx];
817 		init.ops = &vc5_fod_ops;
818 		init.flags = CLK_SET_RATE_PARENT;
819 		init.parent_names = vc5_pll_names;
820 		init.num_parents = 1;
821 		vc5->clk_fod[n].num = idx;
822 		vc5->clk_fod[n].vc5 = vc5;
823 		vc5->clk_fod[n].hw.init = &init;
824 		ret = devm_clk_hw_register(&client->dev, &vc5->clk_fod[n].hw);
825 		if (ret) {
826 			dev_err(&client->dev, "unable to register %s\n",
827 				init.name);
828 			goto err_clk;
829 		}
830 	}
831 
832 	/* Register MUX-connected OUT0_I2C_SELB output */
833 	memset(&init, 0, sizeof(init));
834 	init.name = vc5_clk_out_names[0];
835 	init.ops = &vc5_clk_out_ops;
836 	init.flags = CLK_SET_RATE_PARENT;
837 	init.parent_names = vc5_mux_names;
838 	init.num_parents = 1;
839 	vc5->clk_out[0].num = idx;
840 	vc5->clk_out[0].vc5 = vc5;
841 	vc5->clk_out[0].hw.init = &init;
842 	ret = devm_clk_hw_register(&client->dev, &vc5->clk_out[0].hw);
843 	if (ret) {
844 		dev_err(&client->dev, "unable to register %s\n",
845 			init.name);
846 		goto err_clk;
847 	}
848 
849 	/* Register FOD-connected OUTx outputs */
850 	for (n = 1; n < vc5->chip_info->clk_out_cnt; n++) {
851 		idx = vc5_map_index_to_output(vc5->chip_info->model, n - 1);
852 		parent_names[0] = vc5_fod_names[idx];
853 		if (n == 1)
854 			parent_names[1] = vc5_mux_names[0];
855 		else
856 			parent_names[1] = vc5_clk_out_names[n - 1];
857 
858 		memset(&init, 0, sizeof(init));
859 		init.name = vc5_clk_out_names[idx + 1];
860 		init.ops = &vc5_clk_out_ops;
861 		init.flags = CLK_SET_RATE_PARENT;
862 		init.parent_names = parent_names;
863 		init.num_parents = 2;
864 		vc5->clk_out[n].num = idx;
865 		vc5->clk_out[n].vc5 = vc5;
866 		vc5->clk_out[n].hw.init = &init;
867 		ret = devm_clk_hw_register(&client->dev,
868 					   &vc5->clk_out[n].hw);
869 		if (ret) {
870 			dev_err(&client->dev, "unable to register %s\n",
871 				init.name);
872 			goto err_clk;
873 		}
874 	}
875 
876 	ret = of_clk_add_hw_provider(client->dev.of_node, vc5_of_clk_get, vc5);
877 	if (ret) {
878 		dev_err(&client->dev, "unable to add clk provider\n");
879 		goto err_clk;
880 	}
881 
882 	return 0;
883 
884 err_clk:
885 	if (vc5->chip_info->flags & VC5_HAS_INTERNAL_XTAL)
886 		clk_unregister_fixed_rate(vc5->pin_xin);
887 	return ret;
888 }
889 
890 static int vc5_remove(struct i2c_client *client)
891 {
892 	struct vc5_driver_data *vc5 = i2c_get_clientdata(client);
893 
894 	of_clk_del_provider(client->dev.of_node);
895 
896 	if (vc5->chip_info->flags & VC5_HAS_INTERNAL_XTAL)
897 		clk_unregister_fixed_rate(vc5->pin_xin);
898 
899 	return 0;
900 }
901 
902 static int __maybe_unused vc5_suspend(struct device *dev)
903 {
904 	struct vc5_driver_data *vc5 = dev_get_drvdata(dev);
905 
906 	regcache_cache_only(vc5->regmap, true);
907 	regcache_mark_dirty(vc5->regmap);
908 
909 	return 0;
910 }
911 
912 static int __maybe_unused vc5_resume(struct device *dev)
913 {
914 	struct vc5_driver_data *vc5 = dev_get_drvdata(dev);
915 	int ret;
916 
917 	regcache_cache_only(vc5->regmap, false);
918 	ret = regcache_sync(vc5->regmap);
919 	if (ret)
920 		dev_err(dev, "Failed to restore register map: %d\n", ret);
921 	return ret;
922 }
923 
924 static const struct vc5_chip_info idt_5p49v5923_info = {
925 	.model = IDT_VC5_5P49V5923,
926 	.clk_fod_cnt = 2,
927 	.clk_out_cnt = 3,
928 	.flags = 0,
929 };
930 
931 static const struct vc5_chip_info idt_5p49v5925_info = {
932 	.model = IDT_VC5_5P49V5925,
933 	.clk_fod_cnt = 4,
934 	.clk_out_cnt = 5,
935 	.flags = 0,
936 };
937 
938 static const struct vc5_chip_info idt_5p49v5933_info = {
939 	.model = IDT_VC5_5P49V5933,
940 	.clk_fod_cnt = 2,
941 	.clk_out_cnt = 3,
942 	.flags = VC5_HAS_INTERNAL_XTAL,
943 };
944 
945 static const struct vc5_chip_info idt_5p49v5935_info = {
946 	.model = IDT_VC5_5P49V5935,
947 	.clk_fod_cnt = 4,
948 	.clk_out_cnt = 5,
949 	.flags = VC5_HAS_INTERNAL_XTAL,
950 };
951 
952 static const struct vc5_chip_info idt_5p49v6901_info = {
953 	.model = IDT_VC6_5P49V6901,
954 	.clk_fod_cnt = 4,
955 	.clk_out_cnt = 5,
956 	.flags = VC5_HAS_PFD_FREQ_DBL,
957 };
958 
959 static const struct i2c_device_id vc5_id[] = {
960 	{ "5p49v5923", .driver_data = IDT_VC5_5P49V5923 },
961 	{ "5p49v5925", .driver_data = IDT_VC5_5P49V5925 },
962 	{ "5p49v5933", .driver_data = IDT_VC5_5P49V5933 },
963 	{ "5p49v5935", .driver_data = IDT_VC5_5P49V5935 },
964 	{ "5p49v6901", .driver_data = IDT_VC6_5P49V6901 },
965 	{ }
966 };
967 MODULE_DEVICE_TABLE(i2c, vc5_id);
968 
969 static const struct of_device_id clk_vc5_of_match[] = {
970 	{ .compatible = "idt,5p49v5923", .data = &idt_5p49v5923_info },
971 	{ .compatible = "idt,5p49v5925", .data = &idt_5p49v5925_info },
972 	{ .compatible = "idt,5p49v5933", .data = &idt_5p49v5933_info },
973 	{ .compatible = "idt,5p49v5935", .data = &idt_5p49v5935_info },
974 	{ .compatible = "idt,5p49v6901", .data = &idt_5p49v6901_info },
975 	{ },
976 };
977 MODULE_DEVICE_TABLE(of, clk_vc5_of_match);
978 
979 static SIMPLE_DEV_PM_OPS(vc5_pm_ops, vc5_suspend, vc5_resume);
980 
981 static struct i2c_driver vc5_driver = {
982 	.driver = {
983 		.name = "vc5",
984 		.pm	= &vc5_pm_ops,
985 		.of_match_table = clk_vc5_of_match,
986 	},
987 	.probe		= vc5_probe,
988 	.remove		= vc5_remove,
989 	.id_table	= vc5_id,
990 };
991 module_i2c_driver(vc5_driver);
992 
993 MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
994 MODULE_DESCRIPTION("IDT VersaClock 5 driver");
995 MODULE_LICENSE("GPL");
996