xref: /openbmc/linux/drivers/clk/clk-versaclock5.c (revision 55fd7e02)
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 	IDT_VC6_5P49V6965,
128 };
129 
130 /* Structure to describe features of a particular VC5 model */
131 struct vc5_chip_info {
132 	const enum vc5_model	model;
133 	const unsigned int	clk_fod_cnt;
134 	const unsigned int	clk_out_cnt;
135 	const u32		flags;
136 };
137 
138 struct vc5_driver_data;
139 
140 struct vc5_hw_data {
141 	struct clk_hw		hw;
142 	struct vc5_driver_data	*vc5;
143 	u32			div_int;
144 	u32			div_frc;
145 	unsigned int		num;
146 };
147 
148 struct vc5_driver_data {
149 	struct i2c_client	*client;
150 	struct regmap		*regmap;
151 	const struct vc5_chip_info	*chip_info;
152 
153 	struct clk		*pin_xin;
154 	struct clk		*pin_clkin;
155 	unsigned char		clk_mux_ins;
156 	struct clk_hw		clk_mux;
157 	struct clk_hw		clk_mul;
158 	struct clk_hw		clk_pfd;
159 	struct vc5_hw_data	clk_pll;
160 	struct vc5_hw_data	clk_fod[VC5_MAX_FOD_NUM];
161 	struct vc5_hw_data	clk_out[VC5_MAX_CLK_OUT_NUM];
162 };
163 
164 static const char * const vc5_mux_names[] = {
165 	"mux"
166 };
167 
168 static const char * const vc5_dbl_names[] = {
169 	"dbl"
170 };
171 
172 static const char * const vc5_pfd_names[] = {
173 	"pfd"
174 };
175 
176 static const char * const vc5_pll_names[] = {
177 	"pll"
178 };
179 
180 static const char * const vc5_fod_names[] = {
181 	"fod0", "fod1", "fod2", "fod3",
182 };
183 
184 static const char * const vc5_clk_out_names[] = {
185 	"out0_sel_i2cb", "out1", "out2", "out3", "out4",
186 };
187 
188 /*
189  * VersaClock5 i2c regmap
190  */
191 static bool vc5_regmap_is_writeable(struct device *dev, unsigned int reg)
192 {
193 	/* Factory reserved regs, make them read-only */
194 	if (reg <= 0xf)
195 		return false;
196 
197 	/* Factory reserved regs, make them read-only */
198 	if (reg == 0x14 || reg == 0x1c || reg == 0x1d)
199 		return false;
200 
201 	return true;
202 }
203 
204 static const struct regmap_config vc5_regmap_config = {
205 	.reg_bits = 8,
206 	.val_bits = 8,
207 	.cache_type = REGCACHE_RBTREE,
208 	.max_register = 0x76,
209 	.writeable_reg = vc5_regmap_is_writeable,
210 };
211 
212 /*
213  * VersaClock5 input multiplexer between XTAL and CLKIN divider
214  */
215 static unsigned char vc5_mux_get_parent(struct clk_hw *hw)
216 {
217 	struct vc5_driver_data *vc5 =
218 		container_of(hw, struct vc5_driver_data, clk_mux);
219 	const u8 mask = VC5_PRIM_SRC_SHDN_EN_XTAL | VC5_PRIM_SRC_SHDN_EN_CLKIN;
220 	unsigned int src;
221 
222 	regmap_read(vc5->regmap, VC5_PRIM_SRC_SHDN, &src);
223 	src &= mask;
224 
225 	if (src == VC5_PRIM_SRC_SHDN_EN_XTAL)
226 		return 0;
227 
228 	if (src == VC5_PRIM_SRC_SHDN_EN_CLKIN)
229 		return 1;
230 
231 	dev_warn(&vc5->client->dev,
232 		 "Invalid clock input configuration (%02x)\n", src);
233 	return 0;
234 }
235 
236 static int vc5_mux_set_parent(struct clk_hw *hw, u8 index)
237 {
238 	struct vc5_driver_data *vc5 =
239 		container_of(hw, struct vc5_driver_data, clk_mux);
240 	const u8 mask = VC5_PRIM_SRC_SHDN_EN_XTAL | VC5_PRIM_SRC_SHDN_EN_CLKIN;
241 	u8 src;
242 
243 	if ((index > 1) || !vc5->clk_mux_ins)
244 		return -EINVAL;
245 
246 	if (vc5->clk_mux_ins == (VC5_MUX_IN_CLKIN | VC5_MUX_IN_XIN)) {
247 		if (index == 0)
248 			src = VC5_PRIM_SRC_SHDN_EN_XTAL;
249 		if (index == 1)
250 			src = VC5_PRIM_SRC_SHDN_EN_CLKIN;
251 	} else {
252 		if (index != 0)
253 			return -EINVAL;
254 
255 		if (vc5->clk_mux_ins == VC5_MUX_IN_XIN)
256 			src = VC5_PRIM_SRC_SHDN_EN_XTAL;
257 		else if (vc5->clk_mux_ins == VC5_MUX_IN_CLKIN)
258 			src = VC5_PRIM_SRC_SHDN_EN_CLKIN;
259 		else /* Invalid; should have been caught by vc5_probe() */
260 			return -EINVAL;
261 	}
262 
263 	return regmap_update_bits(vc5->regmap, VC5_PRIM_SRC_SHDN, mask, src);
264 }
265 
266 static const struct clk_ops vc5_mux_ops = {
267 	.set_parent	= vc5_mux_set_parent,
268 	.get_parent	= vc5_mux_get_parent,
269 };
270 
271 static unsigned long vc5_dbl_recalc_rate(struct clk_hw *hw,
272 					 unsigned long parent_rate)
273 {
274 	struct vc5_driver_data *vc5 =
275 		container_of(hw, struct vc5_driver_data, clk_mul);
276 	unsigned int premul;
277 
278 	regmap_read(vc5->regmap, VC5_PRIM_SRC_SHDN, &premul);
279 	if (premul & VC5_PRIM_SRC_SHDN_EN_DOUBLE_XTAL_FREQ)
280 		parent_rate *= 2;
281 
282 	return parent_rate;
283 }
284 
285 static long vc5_dbl_round_rate(struct clk_hw *hw, unsigned long rate,
286 			       unsigned long *parent_rate)
287 {
288 	if ((*parent_rate == rate) || ((*parent_rate * 2) == rate))
289 		return rate;
290 	else
291 		return -EINVAL;
292 }
293 
294 static int vc5_dbl_set_rate(struct clk_hw *hw, unsigned long rate,
295 			    unsigned long parent_rate)
296 {
297 	struct vc5_driver_data *vc5 =
298 		container_of(hw, struct vc5_driver_data, clk_mul);
299 	u32 mask;
300 
301 	if ((parent_rate * 2) == rate)
302 		mask = VC5_PRIM_SRC_SHDN_EN_DOUBLE_XTAL_FREQ;
303 	else
304 		mask = 0;
305 
306 	regmap_update_bits(vc5->regmap, VC5_PRIM_SRC_SHDN,
307 			   VC5_PRIM_SRC_SHDN_EN_DOUBLE_XTAL_FREQ,
308 			   mask);
309 
310 	return 0;
311 }
312 
313 static const struct clk_ops vc5_dbl_ops = {
314 	.recalc_rate	= vc5_dbl_recalc_rate,
315 	.round_rate	= vc5_dbl_round_rate,
316 	.set_rate	= vc5_dbl_set_rate,
317 };
318 
319 static unsigned long vc5_pfd_recalc_rate(struct clk_hw *hw,
320 					 unsigned long parent_rate)
321 {
322 	struct vc5_driver_data *vc5 =
323 		container_of(hw, struct vc5_driver_data, clk_pfd);
324 	unsigned int prediv, div;
325 
326 	regmap_read(vc5->regmap, VC5_VCO_CTRL_AND_PREDIV, &prediv);
327 
328 	/* The bypass_prediv is set, PLL fed from Ref_in directly. */
329 	if (prediv & VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV)
330 		return parent_rate;
331 
332 	regmap_read(vc5->regmap, VC5_REF_DIVIDER, &div);
333 
334 	/* The Sel_prediv2 is set, PLL fed from prediv2 (Ref_in / 2) */
335 	if (div & VC5_REF_DIVIDER_SEL_PREDIV2)
336 		return parent_rate / 2;
337 	else
338 		return parent_rate / VC5_REF_DIVIDER_REF_DIV(div);
339 }
340 
341 static long vc5_pfd_round_rate(struct clk_hw *hw, unsigned long rate,
342 			       unsigned long *parent_rate)
343 {
344 	unsigned long idiv;
345 
346 	/* PLL cannot operate with input clock above 50 MHz. */
347 	if (rate > 50000000)
348 		return -EINVAL;
349 
350 	/* CLKIN within range of PLL input, feed directly to PLL. */
351 	if (*parent_rate <= 50000000)
352 		return *parent_rate;
353 
354 	idiv = DIV_ROUND_UP(*parent_rate, rate);
355 	if (idiv > 127)
356 		return -EINVAL;
357 
358 	return *parent_rate / idiv;
359 }
360 
361 static int vc5_pfd_set_rate(struct clk_hw *hw, unsigned long rate,
362 			    unsigned long parent_rate)
363 {
364 	struct vc5_driver_data *vc5 =
365 		container_of(hw, struct vc5_driver_data, clk_pfd);
366 	unsigned long idiv;
367 	u8 div;
368 
369 	/* CLKIN within range of PLL input, feed directly to PLL. */
370 	if (parent_rate <= 50000000) {
371 		regmap_update_bits(vc5->regmap, VC5_VCO_CTRL_AND_PREDIV,
372 				   VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV,
373 				   VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV);
374 		regmap_update_bits(vc5->regmap, VC5_REF_DIVIDER, 0xff, 0x00);
375 		return 0;
376 	}
377 
378 	idiv = DIV_ROUND_UP(parent_rate, rate);
379 
380 	/* We have dedicated div-2 predivider. */
381 	if (idiv == 2)
382 		div = VC5_REF_DIVIDER_SEL_PREDIV2;
383 	else
384 		div = VC5_REF_DIVIDER_REF_DIV(idiv);
385 
386 	regmap_update_bits(vc5->regmap, VC5_REF_DIVIDER, 0xff, div);
387 	regmap_update_bits(vc5->regmap, VC5_VCO_CTRL_AND_PREDIV,
388 			   VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV, 0);
389 
390 	return 0;
391 }
392 
393 static const struct clk_ops vc5_pfd_ops = {
394 	.recalc_rate	= vc5_pfd_recalc_rate,
395 	.round_rate	= vc5_pfd_round_rate,
396 	.set_rate	= vc5_pfd_set_rate,
397 };
398 
399 /*
400  * VersaClock5 PLL/VCO
401  */
402 static unsigned long vc5_pll_recalc_rate(struct clk_hw *hw,
403 					 unsigned long parent_rate)
404 {
405 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
406 	struct vc5_driver_data *vc5 = hwdata->vc5;
407 	u32 div_int, div_frc;
408 	u8 fb[5];
409 
410 	regmap_bulk_read(vc5->regmap, VC5_FEEDBACK_INT_DIV, fb, 5);
411 
412 	div_int = (fb[0] << 4) | (fb[1] >> 4);
413 	div_frc = (fb[2] << 16) | (fb[3] << 8) | fb[4];
414 
415 	/* The PLL divider has 12 integer bits and 24 fractional bits */
416 	return (parent_rate * div_int) + ((parent_rate * div_frc) >> 24);
417 }
418 
419 static long vc5_pll_round_rate(struct clk_hw *hw, unsigned long rate,
420 			       unsigned long *parent_rate)
421 {
422 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
423 	u32 div_int;
424 	u64 div_frc;
425 
426 	if (rate < VC5_PLL_VCO_MIN)
427 		rate = VC5_PLL_VCO_MIN;
428 	if (rate > VC5_PLL_VCO_MAX)
429 		rate = VC5_PLL_VCO_MAX;
430 
431 	/* Determine integer part, which is 12 bit wide */
432 	div_int = rate / *parent_rate;
433 	if (div_int > 0xfff)
434 		rate = *parent_rate * 0xfff;
435 
436 	/* Determine best fractional part, which is 24 bit wide */
437 	div_frc = rate % *parent_rate;
438 	div_frc *= BIT(24) - 1;
439 	do_div(div_frc, *parent_rate);
440 
441 	hwdata->div_int = div_int;
442 	hwdata->div_frc = (u32)div_frc;
443 
444 	return (*parent_rate * div_int) + ((*parent_rate * div_frc) >> 24);
445 }
446 
447 static int vc5_pll_set_rate(struct clk_hw *hw, unsigned long rate,
448 			    unsigned long parent_rate)
449 {
450 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
451 	struct vc5_driver_data *vc5 = hwdata->vc5;
452 	u8 fb[5];
453 
454 	fb[0] = hwdata->div_int >> 4;
455 	fb[1] = hwdata->div_int << 4;
456 	fb[2] = hwdata->div_frc >> 16;
457 	fb[3] = hwdata->div_frc >> 8;
458 	fb[4] = hwdata->div_frc;
459 
460 	return regmap_bulk_write(vc5->regmap, VC5_FEEDBACK_INT_DIV, fb, 5);
461 }
462 
463 static const struct clk_ops vc5_pll_ops = {
464 	.recalc_rate	= vc5_pll_recalc_rate,
465 	.round_rate	= vc5_pll_round_rate,
466 	.set_rate	= vc5_pll_set_rate,
467 };
468 
469 static unsigned long vc5_fod_recalc_rate(struct clk_hw *hw,
470 					 unsigned long parent_rate)
471 {
472 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
473 	struct vc5_driver_data *vc5 = hwdata->vc5;
474 	/* VCO frequency is divided by two before entering FOD */
475 	u32 f_in = parent_rate / 2;
476 	u32 div_int, div_frc;
477 	u8 od_int[2];
478 	u8 od_frc[4];
479 
480 	regmap_bulk_read(vc5->regmap, VC5_OUT_DIV_INT(hwdata->num, 0),
481 			 od_int, 2);
482 	regmap_bulk_read(vc5->regmap, VC5_OUT_DIV_FRAC(hwdata->num, 0),
483 			 od_frc, 4);
484 
485 	div_int = (od_int[0] << 4) | (od_int[1] >> 4);
486 	div_frc = (od_frc[0] << 22) | (od_frc[1] << 14) |
487 		  (od_frc[2] << 6) | (od_frc[3] >> 2);
488 
489 	/* Avoid division by zero if the output is not configured. */
490 	if (div_int == 0 && div_frc == 0)
491 		return 0;
492 
493 	/* The PLL divider has 12 integer bits and 30 fractional bits */
494 	return div64_u64((u64)f_in << 24ULL, ((u64)div_int << 24ULL) + div_frc);
495 }
496 
497 static long vc5_fod_round_rate(struct clk_hw *hw, unsigned long rate,
498 			       unsigned long *parent_rate)
499 {
500 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
501 	/* VCO frequency is divided by two before entering FOD */
502 	u32 f_in = *parent_rate / 2;
503 	u32 div_int;
504 	u64 div_frc;
505 
506 	/* Determine integer part, which is 12 bit wide */
507 	div_int = f_in / rate;
508 	/*
509 	 * WARNING: The clock chip does not output signal if the integer part
510 	 *          of the divider is 0xfff and fractional part is non-zero.
511 	 *          Clamp the divider at 0xffe to keep the code simple.
512 	 */
513 	if (div_int > 0xffe) {
514 		div_int = 0xffe;
515 		rate = f_in / div_int;
516 	}
517 
518 	/* Determine best fractional part, which is 30 bit wide */
519 	div_frc = f_in % rate;
520 	div_frc <<= 24;
521 	do_div(div_frc, rate);
522 
523 	hwdata->div_int = div_int;
524 	hwdata->div_frc = (u32)div_frc;
525 
526 	return div64_u64((u64)f_in << 24ULL, ((u64)div_int << 24ULL) + div_frc);
527 }
528 
529 static int vc5_fod_set_rate(struct clk_hw *hw, unsigned long rate,
530 			    unsigned long parent_rate)
531 {
532 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
533 	struct vc5_driver_data *vc5 = hwdata->vc5;
534 	u8 data[14] = {
535 		hwdata->div_frc >> 22, hwdata->div_frc >> 14,
536 		hwdata->div_frc >> 6, hwdata->div_frc << 2,
537 		0, 0, 0, 0, 0,
538 		0, 0,
539 		hwdata->div_int >> 4, hwdata->div_int << 4,
540 		0
541 	};
542 
543 	regmap_bulk_write(vc5->regmap, VC5_OUT_DIV_FRAC(hwdata->num, 0),
544 			  data, 14);
545 
546 	/*
547 	 * Toggle magic bit in undocumented register for unknown reason.
548 	 * This is what the IDT timing commander tool does and the chip
549 	 * datasheet somewhat implies this is needed, but the register
550 	 * and the bit is not documented.
551 	 */
552 	regmap_update_bits(vc5->regmap, VC5_GLOBAL_REGISTER,
553 			   VC5_GLOBAL_REGISTER_GLOBAL_RESET, 0);
554 	regmap_update_bits(vc5->regmap, VC5_GLOBAL_REGISTER,
555 			   VC5_GLOBAL_REGISTER_GLOBAL_RESET,
556 			   VC5_GLOBAL_REGISTER_GLOBAL_RESET);
557 	return 0;
558 }
559 
560 static const struct clk_ops vc5_fod_ops = {
561 	.recalc_rate	= vc5_fod_recalc_rate,
562 	.round_rate	= vc5_fod_round_rate,
563 	.set_rate	= vc5_fod_set_rate,
564 };
565 
566 static int vc5_clk_out_prepare(struct clk_hw *hw)
567 {
568 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
569 	struct vc5_driver_data *vc5 = hwdata->vc5;
570 	const u8 mask = VC5_OUT_DIV_CONTROL_SELB_NORM |
571 			VC5_OUT_DIV_CONTROL_SEL_EXT |
572 			VC5_OUT_DIV_CONTROL_EN_FOD;
573 	unsigned int src;
574 	int ret;
575 
576 	/*
577 	 * If the input mux is disabled, enable it first and
578 	 * select source from matching FOD.
579 	 */
580 	regmap_read(vc5->regmap, VC5_OUT_DIV_CONTROL(hwdata->num), &src);
581 	if ((src & mask) == 0) {
582 		src = VC5_OUT_DIV_CONTROL_RESET | VC5_OUT_DIV_CONTROL_EN_FOD;
583 		ret = regmap_update_bits(vc5->regmap,
584 					 VC5_OUT_DIV_CONTROL(hwdata->num),
585 					 mask | VC5_OUT_DIV_CONTROL_RESET, src);
586 		if (ret)
587 			return ret;
588 	}
589 
590 	/* Enable the clock buffer */
591 	regmap_update_bits(vc5->regmap, VC5_CLK_OUTPUT_CFG(hwdata->num, 1),
592 			   VC5_CLK_OUTPUT_CFG1_EN_CLKBUF,
593 			   VC5_CLK_OUTPUT_CFG1_EN_CLKBUF);
594 	return 0;
595 }
596 
597 static void vc5_clk_out_unprepare(struct clk_hw *hw)
598 {
599 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
600 	struct vc5_driver_data *vc5 = hwdata->vc5;
601 
602 	/* Disable the clock buffer */
603 	regmap_update_bits(vc5->regmap, VC5_CLK_OUTPUT_CFG(hwdata->num, 1),
604 			   VC5_CLK_OUTPUT_CFG1_EN_CLKBUF, 0);
605 }
606 
607 static unsigned char vc5_clk_out_get_parent(struct clk_hw *hw)
608 {
609 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
610 	struct vc5_driver_data *vc5 = hwdata->vc5;
611 	const u8 mask = VC5_OUT_DIV_CONTROL_SELB_NORM |
612 			VC5_OUT_DIV_CONTROL_SEL_EXT |
613 			VC5_OUT_DIV_CONTROL_EN_FOD;
614 	const u8 fodclkmask = VC5_OUT_DIV_CONTROL_SELB_NORM |
615 			      VC5_OUT_DIV_CONTROL_EN_FOD;
616 	const u8 extclk = VC5_OUT_DIV_CONTROL_SELB_NORM |
617 			  VC5_OUT_DIV_CONTROL_SEL_EXT;
618 	unsigned int src;
619 
620 	regmap_read(vc5->regmap, VC5_OUT_DIV_CONTROL(hwdata->num), &src);
621 	src &= mask;
622 
623 	if (src == 0)	/* Input mux set to DISABLED */
624 		return 0;
625 
626 	if ((src & fodclkmask) == VC5_OUT_DIV_CONTROL_EN_FOD)
627 		return 0;
628 
629 	if (src == extclk)
630 		return 1;
631 
632 	dev_warn(&vc5->client->dev,
633 		 "Invalid clock output configuration (%02x)\n", src);
634 	return 0;
635 }
636 
637 static int vc5_clk_out_set_parent(struct clk_hw *hw, u8 index)
638 {
639 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
640 	struct vc5_driver_data *vc5 = hwdata->vc5;
641 	const u8 mask = VC5_OUT_DIV_CONTROL_RESET |
642 			VC5_OUT_DIV_CONTROL_SELB_NORM |
643 			VC5_OUT_DIV_CONTROL_SEL_EXT |
644 			VC5_OUT_DIV_CONTROL_EN_FOD;
645 	const u8 extclk = VC5_OUT_DIV_CONTROL_SELB_NORM |
646 			  VC5_OUT_DIV_CONTROL_SEL_EXT;
647 	u8 src = VC5_OUT_DIV_CONTROL_RESET;
648 
649 	if (index == 0)
650 		src |= VC5_OUT_DIV_CONTROL_EN_FOD;
651 	else
652 		src |= extclk;
653 
654 	return regmap_update_bits(vc5->regmap, VC5_OUT_DIV_CONTROL(hwdata->num),
655 				  mask, src);
656 }
657 
658 static const struct clk_ops vc5_clk_out_ops = {
659 	.prepare	= vc5_clk_out_prepare,
660 	.unprepare	= vc5_clk_out_unprepare,
661 	.set_parent	= vc5_clk_out_set_parent,
662 	.get_parent	= vc5_clk_out_get_parent,
663 };
664 
665 static struct clk_hw *vc5_of_clk_get(struct of_phandle_args *clkspec,
666 				     void *data)
667 {
668 	struct vc5_driver_data *vc5 = data;
669 	unsigned int idx = clkspec->args[0];
670 
671 	if (idx >= vc5->chip_info->clk_out_cnt)
672 		return ERR_PTR(-EINVAL);
673 
674 	return &vc5->clk_out[idx].hw;
675 }
676 
677 static int vc5_map_index_to_output(const enum vc5_model model,
678 				   const unsigned int n)
679 {
680 	switch (model) {
681 	case IDT_VC5_5P49V5933:
682 		return (n == 0) ? 0 : 3;
683 	case IDT_VC5_5P49V5923:
684 	case IDT_VC5_5P49V5925:
685 	case IDT_VC5_5P49V5935:
686 	case IDT_VC6_5P49V6901:
687 	case IDT_VC6_5P49V6965:
688 	default:
689 		return n;
690 	}
691 }
692 
693 static const struct of_device_id clk_vc5_of_match[];
694 
695 static int vc5_probe(struct i2c_client *client,
696 		     const struct i2c_device_id *id)
697 {
698 	struct vc5_driver_data *vc5;
699 	struct clk_init_data init;
700 	const char *parent_names[2];
701 	unsigned int n, idx = 0;
702 	int ret;
703 
704 	vc5 = devm_kzalloc(&client->dev, sizeof(*vc5), GFP_KERNEL);
705 	if (vc5 == NULL)
706 		return -ENOMEM;
707 
708 	i2c_set_clientdata(client, vc5);
709 	vc5->client = client;
710 	vc5->chip_info = of_device_get_match_data(&client->dev);
711 
712 	vc5->pin_xin = devm_clk_get(&client->dev, "xin");
713 	if (PTR_ERR(vc5->pin_xin) == -EPROBE_DEFER)
714 		return -EPROBE_DEFER;
715 
716 	vc5->pin_clkin = devm_clk_get(&client->dev, "clkin");
717 	if (PTR_ERR(vc5->pin_clkin) == -EPROBE_DEFER)
718 		return -EPROBE_DEFER;
719 
720 	vc5->regmap = devm_regmap_init_i2c(client, &vc5_regmap_config);
721 	if (IS_ERR(vc5->regmap)) {
722 		dev_err(&client->dev, "failed to allocate register map\n");
723 		return PTR_ERR(vc5->regmap);
724 	}
725 
726 	/* Register clock input mux */
727 	memset(&init, 0, sizeof(init));
728 
729 	if (!IS_ERR(vc5->pin_xin)) {
730 		vc5->clk_mux_ins |= VC5_MUX_IN_XIN;
731 		parent_names[init.num_parents++] = __clk_get_name(vc5->pin_xin);
732 	} else if (vc5->chip_info->flags & VC5_HAS_INTERNAL_XTAL) {
733 		vc5->pin_xin = clk_register_fixed_rate(&client->dev,
734 						       "internal-xtal", NULL,
735 						       0, 25000000);
736 		if (IS_ERR(vc5->pin_xin))
737 			return PTR_ERR(vc5->pin_xin);
738 		vc5->clk_mux_ins |= VC5_MUX_IN_XIN;
739 		parent_names[init.num_parents++] = __clk_get_name(vc5->pin_xin);
740 	}
741 
742 	if (!IS_ERR(vc5->pin_clkin)) {
743 		vc5->clk_mux_ins |= VC5_MUX_IN_CLKIN;
744 		parent_names[init.num_parents++] =
745 			__clk_get_name(vc5->pin_clkin);
746 	}
747 
748 	if (!init.num_parents) {
749 		dev_err(&client->dev, "no input clock specified!\n");
750 		return -EINVAL;
751 	}
752 
753 	init.name = vc5_mux_names[0];
754 	init.ops = &vc5_mux_ops;
755 	init.flags = 0;
756 	init.parent_names = parent_names;
757 	vc5->clk_mux.init = &init;
758 	ret = devm_clk_hw_register(&client->dev, &vc5->clk_mux);
759 	if (ret) {
760 		dev_err(&client->dev, "unable to register %s\n", init.name);
761 		goto err_clk;
762 	}
763 
764 	if (vc5->chip_info->flags & VC5_HAS_PFD_FREQ_DBL) {
765 		/* Register frequency doubler */
766 		memset(&init, 0, sizeof(init));
767 		init.name = vc5_dbl_names[0];
768 		init.ops = &vc5_dbl_ops;
769 		init.flags = CLK_SET_RATE_PARENT;
770 		init.parent_names = vc5_mux_names;
771 		init.num_parents = 1;
772 		vc5->clk_mul.init = &init;
773 		ret = devm_clk_hw_register(&client->dev, &vc5->clk_mul);
774 		if (ret) {
775 			dev_err(&client->dev, "unable to register %s\n",
776 				init.name);
777 			goto err_clk;
778 		}
779 	}
780 
781 	/* Register PFD */
782 	memset(&init, 0, sizeof(init));
783 	init.name = vc5_pfd_names[0];
784 	init.ops = &vc5_pfd_ops;
785 	init.flags = CLK_SET_RATE_PARENT;
786 	if (vc5->chip_info->flags & VC5_HAS_PFD_FREQ_DBL)
787 		init.parent_names = vc5_dbl_names;
788 	else
789 		init.parent_names = vc5_mux_names;
790 	init.num_parents = 1;
791 	vc5->clk_pfd.init = &init;
792 	ret = devm_clk_hw_register(&client->dev, &vc5->clk_pfd);
793 	if (ret) {
794 		dev_err(&client->dev, "unable to register %s\n", init.name);
795 		goto err_clk;
796 	}
797 
798 	/* Register PLL */
799 	memset(&init, 0, sizeof(init));
800 	init.name = vc5_pll_names[0];
801 	init.ops = &vc5_pll_ops;
802 	init.flags = CLK_SET_RATE_PARENT;
803 	init.parent_names = vc5_pfd_names;
804 	init.num_parents = 1;
805 	vc5->clk_pll.num = 0;
806 	vc5->clk_pll.vc5 = vc5;
807 	vc5->clk_pll.hw.init = &init;
808 	ret = devm_clk_hw_register(&client->dev, &vc5->clk_pll.hw);
809 	if (ret) {
810 		dev_err(&client->dev, "unable to register %s\n", init.name);
811 		goto err_clk;
812 	}
813 
814 	/* Register FODs */
815 	for (n = 0; n < vc5->chip_info->clk_fod_cnt; n++) {
816 		idx = vc5_map_index_to_output(vc5->chip_info->model, n);
817 		memset(&init, 0, sizeof(init));
818 		init.name = vc5_fod_names[idx];
819 		init.ops = &vc5_fod_ops;
820 		init.flags = CLK_SET_RATE_PARENT;
821 		init.parent_names = vc5_pll_names;
822 		init.num_parents = 1;
823 		vc5->clk_fod[n].num = idx;
824 		vc5->clk_fod[n].vc5 = vc5;
825 		vc5->clk_fod[n].hw.init = &init;
826 		ret = devm_clk_hw_register(&client->dev, &vc5->clk_fod[n].hw);
827 		if (ret) {
828 			dev_err(&client->dev, "unable to register %s\n",
829 				init.name);
830 			goto err_clk;
831 		}
832 	}
833 
834 	/* Register MUX-connected OUT0_I2C_SELB output */
835 	memset(&init, 0, sizeof(init));
836 	init.name = vc5_clk_out_names[0];
837 	init.ops = &vc5_clk_out_ops;
838 	init.flags = CLK_SET_RATE_PARENT;
839 	init.parent_names = vc5_mux_names;
840 	init.num_parents = 1;
841 	vc5->clk_out[0].num = idx;
842 	vc5->clk_out[0].vc5 = vc5;
843 	vc5->clk_out[0].hw.init = &init;
844 	ret = devm_clk_hw_register(&client->dev, &vc5->clk_out[0].hw);
845 	if (ret) {
846 		dev_err(&client->dev, "unable to register %s\n",
847 			init.name);
848 		goto err_clk;
849 	}
850 
851 	/* Register FOD-connected OUTx outputs */
852 	for (n = 1; n < vc5->chip_info->clk_out_cnt; n++) {
853 		idx = vc5_map_index_to_output(vc5->chip_info->model, n - 1);
854 		parent_names[0] = vc5_fod_names[idx];
855 		if (n == 1)
856 			parent_names[1] = vc5_mux_names[0];
857 		else
858 			parent_names[1] = vc5_clk_out_names[n - 1];
859 
860 		memset(&init, 0, sizeof(init));
861 		init.name = vc5_clk_out_names[idx + 1];
862 		init.ops = &vc5_clk_out_ops;
863 		init.flags = CLK_SET_RATE_PARENT;
864 		init.parent_names = parent_names;
865 		init.num_parents = 2;
866 		vc5->clk_out[n].num = idx;
867 		vc5->clk_out[n].vc5 = vc5;
868 		vc5->clk_out[n].hw.init = &init;
869 		ret = devm_clk_hw_register(&client->dev,
870 					   &vc5->clk_out[n].hw);
871 		if (ret) {
872 			dev_err(&client->dev, "unable to register %s\n",
873 				init.name);
874 			goto err_clk;
875 		}
876 	}
877 
878 	ret = of_clk_add_hw_provider(client->dev.of_node, vc5_of_clk_get, vc5);
879 	if (ret) {
880 		dev_err(&client->dev, "unable to add clk provider\n");
881 		goto err_clk;
882 	}
883 
884 	return 0;
885 
886 err_clk:
887 	if (vc5->chip_info->flags & VC5_HAS_INTERNAL_XTAL)
888 		clk_unregister_fixed_rate(vc5->pin_xin);
889 	return ret;
890 }
891 
892 static int vc5_remove(struct i2c_client *client)
893 {
894 	struct vc5_driver_data *vc5 = i2c_get_clientdata(client);
895 
896 	of_clk_del_provider(client->dev.of_node);
897 
898 	if (vc5->chip_info->flags & VC5_HAS_INTERNAL_XTAL)
899 		clk_unregister_fixed_rate(vc5->pin_xin);
900 
901 	return 0;
902 }
903 
904 static int __maybe_unused vc5_suspend(struct device *dev)
905 {
906 	struct vc5_driver_data *vc5 = dev_get_drvdata(dev);
907 
908 	regcache_cache_only(vc5->regmap, true);
909 	regcache_mark_dirty(vc5->regmap);
910 
911 	return 0;
912 }
913 
914 static int __maybe_unused vc5_resume(struct device *dev)
915 {
916 	struct vc5_driver_data *vc5 = dev_get_drvdata(dev);
917 	int ret;
918 
919 	regcache_cache_only(vc5->regmap, false);
920 	ret = regcache_sync(vc5->regmap);
921 	if (ret)
922 		dev_err(dev, "Failed to restore register map: %d\n", ret);
923 	return ret;
924 }
925 
926 static const struct vc5_chip_info idt_5p49v5923_info = {
927 	.model = IDT_VC5_5P49V5923,
928 	.clk_fod_cnt = 2,
929 	.clk_out_cnt = 3,
930 	.flags = 0,
931 };
932 
933 static const struct vc5_chip_info idt_5p49v5925_info = {
934 	.model = IDT_VC5_5P49V5925,
935 	.clk_fod_cnt = 4,
936 	.clk_out_cnt = 5,
937 	.flags = 0,
938 };
939 
940 static const struct vc5_chip_info idt_5p49v5933_info = {
941 	.model = IDT_VC5_5P49V5933,
942 	.clk_fod_cnt = 2,
943 	.clk_out_cnt = 3,
944 	.flags = VC5_HAS_INTERNAL_XTAL,
945 };
946 
947 static const struct vc5_chip_info idt_5p49v5935_info = {
948 	.model = IDT_VC5_5P49V5935,
949 	.clk_fod_cnt = 4,
950 	.clk_out_cnt = 5,
951 	.flags = VC5_HAS_INTERNAL_XTAL,
952 };
953 
954 static const struct vc5_chip_info idt_5p49v6901_info = {
955 	.model = IDT_VC6_5P49V6901,
956 	.clk_fod_cnt = 4,
957 	.clk_out_cnt = 5,
958 	.flags = VC5_HAS_PFD_FREQ_DBL,
959 };
960 
961 static const struct vc5_chip_info idt_5p49v6965_info = {
962 	.model = IDT_VC6_5P49V6965,
963 	.clk_fod_cnt = 4,
964 	.clk_out_cnt = 5,
965 	.flags = 0,
966 };
967 
968 static const struct i2c_device_id vc5_id[] = {
969 	{ "5p49v5923", .driver_data = IDT_VC5_5P49V5923 },
970 	{ "5p49v5925", .driver_data = IDT_VC5_5P49V5925 },
971 	{ "5p49v5933", .driver_data = IDT_VC5_5P49V5933 },
972 	{ "5p49v5935", .driver_data = IDT_VC5_5P49V5935 },
973 	{ "5p49v6901", .driver_data = IDT_VC6_5P49V6901 },
974 	{ "5p49v6965", .driver_data = IDT_VC6_5P49V6965 },
975 	{ }
976 };
977 MODULE_DEVICE_TABLE(i2c, vc5_id);
978 
979 static const struct of_device_id clk_vc5_of_match[] = {
980 	{ .compatible = "idt,5p49v5923", .data = &idt_5p49v5923_info },
981 	{ .compatible = "idt,5p49v5925", .data = &idt_5p49v5925_info },
982 	{ .compatible = "idt,5p49v5933", .data = &idt_5p49v5933_info },
983 	{ .compatible = "idt,5p49v5935", .data = &idt_5p49v5935_info },
984 	{ .compatible = "idt,5p49v6901", .data = &idt_5p49v6901_info },
985 	{ .compatible = "idt,5p49v6965", .data = &idt_5p49v6965_info },
986 	{ },
987 };
988 MODULE_DEVICE_TABLE(of, clk_vc5_of_match);
989 
990 static SIMPLE_DEV_PM_OPS(vc5_pm_ops, vc5_suspend, vc5_resume);
991 
992 static struct i2c_driver vc5_driver = {
993 	.driver = {
994 		.name = "vc5",
995 		.pm	= &vc5_pm_ops,
996 		.of_match_table = clk_vc5_of_match,
997 	},
998 	.probe		= vc5_probe,
999 	.remove		= vc5_remove,
1000 	.id_table	= vc5_id,
1001 };
1002 module_i2c_driver(vc5_driver);
1003 
1004 MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
1005 MODULE_DESCRIPTION("IDT VersaClock 5 driver");
1006 MODULE_LICENSE("GPL");
1007