xref: /openbmc/linux/drivers/clk/clk-si5341.c (revision 0ad53fe3)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for Silicon Labs Si5340, Si5341, Si5342, Si5344 and Si5345
4  * Copyright (C) 2019 Topic Embedded Products
5  * Author: Mike Looijmans <mike.looijmans@topic.nl>
6  *
7  * The Si5341 has 10 outputs and 5 synthesizers.
8  * The Si5340 is a smaller version of the Si5341 with only 4 outputs.
9  * The Si5345 is similar to the Si5341, with the addition of fractional input
10  * dividers and automatic input selection.
11  * The Si5342 and Si5344 are smaller versions of the Si5345.
12  */
13 
14 #include <linux/clk.h>
15 #include <linux/clk-provider.h>
16 #include <linux/delay.h>
17 #include <linux/gcd.h>
18 #include <linux/math64.h>
19 #include <linux/i2c.h>
20 #include <linux/module.h>
21 #include <linux/regmap.h>
22 #include <linux/regulator/consumer.h>
23 #include <linux/slab.h>
24 #include <asm/unaligned.h>
25 
26 #define SI5341_NUM_INPUTS 4
27 
28 #define SI5340_MAX_NUM_OUTPUTS 4
29 #define SI5341_MAX_NUM_OUTPUTS 10
30 #define SI5342_MAX_NUM_OUTPUTS 2
31 #define SI5344_MAX_NUM_OUTPUTS 4
32 #define SI5345_MAX_NUM_OUTPUTS 10
33 
34 #define SI5340_NUM_SYNTH 4
35 #define SI5341_NUM_SYNTH 5
36 #define SI5342_NUM_SYNTH 2
37 #define SI5344_NUM_SYNTH 4
38 #define SI5345_NUM_SYNTH 5
39 
40 /* Range of the synthesizer fractional divider */
41 #define SI5341_SYNTH_N_MIN	10
42 #define SI5341_SYNTH_N_MAX	4095
43 
44 /* The chip can get its input clock from 3 input pins or an XTAL */
45 
46 /* There is one PLL running at 13500–14256 MHz */
47 #define SI5341_PLL_VCO_MIN 13500000000ull
48 #define SI5341_PLL_VCO_MAX 14256000000ull
49 
50 /* The 5 frequency synthesizers obtain their input from the PLL */
51 struct clk_si5341_synth {
52 	struct clk_hw hw;
53 	struct clk_si5341 *data;
54 	u8 index;
55 };
56 #define to_clk_si5341_synth(_hw) \
57 	container_of(_hw, struct clk_si5341_synth, hw)
58 
59 /* The output stages can be connected to any synth (full mux) */
60 struct clk_si5341_output {
61 	struct clk_hw hw;
62 	struct clk_si5341 *data;
63 	struct regulator *vddo_reg;
64 	u8 index;
65 };
66 #define to_clk_si5341_output(_hw) \
67 	container_of(_hw, struct clk_si5341_output, hw)
68 
69 struct clk_si5341 {
70 	struct clk_hw hw;
71 	struct regmap *regmap;
72 	struct i2c_client *i2c_client;
73 	struct clk_si5341_synth synth[SI5341_NUM_SYNTH];
74 	struct clk_si5341_output clk[SI5341_MAX_NUM_OUTPUTS];
75 	struct clk *input_clk[SI5341_NUM_INPUTS];
76 	const char *input_clk_name[SI5341_NUM_INPUTS];
77 	const u16 *reg_output_offset;
78 	const u16 *reg_rdiv_offset;
79 	u64 freq_vco; /* 13500–14256 MHz */
80 	u8 num_outputs;
81 	u8 num_synth;
82 	u16 chip_id;
83 	bool xaxb_ext_clk;
84 	bool iovdd_33;
85 };
86 #define to_clk_si5341(_hw)	container_of(_hw, struct clk_si5341, hw)
87 
88 struct clk_si5341_output_config {
89 	u8 out_format_drv_bits;
90 	u8 out_cm_ampl_bits;
91 	u8 vdd_sel_bits;
92 	bool synth_master;
93 	bool always_on;
94 };
95 
96 #define SI5341_PAGE		0x0001
97 #define SI5341_PN_BASE		0x0002
98 #define SI5341_DEVICE_REV	0x0005
99 #define SI5341_STATUS		0x000C
100 #define SI5341_LOS		0x000D
101 #define SI5341_STATUS_STICKY	0x0011
102 #define SI5341_LOS_STICKY	0x0012
103 #define SI5341_SOFT_RST		0x001C
104 #define SI5341_IN_SEL		0x0021
105 #define SI5341_DEVICE_READY	0x00FE
106 #define SI5341_XAXB_CFG		0x090E
107 #define SI5341_IO_VDD_SEL	0x0943
108 #define SI5341_IN_EN		0x0949
109 #define SI5341_INX_TO_PFD_EN	0x094A
110 
111 /* Status bits */
112 #define SI5341_STATUS_SYSINCAL	BIT(0)
113 #define SI5341_STATUS_LOSXAXB	BIT(1)
114 #define SI5341_STATUS_LOSREF	BIT(2)
115 #define SI5341_STATUS_LOL	BIT(3)
116 
117 /* Input selection */
118 #define SI5341_IN_SEL_MASK	0x06
119 #define SI5341_IN_SEL_SHIFT	1
120 #define SI5341_IN_SEL_REGCTRL	0x01
121 #define SI5341_INX_TO_PFD_SHIFT	4
122 
123 /* XTAL config bits */
124 #define SI5341_XAXB_CFG_EXTCLK_EN	BIT(0)
125 #define SI5341_XAXB_CFG_PDNB		BIT(1)
126 
127 /* Input dividers (48-bit) */
128 #define SI5341_IN_PDIV(x)	(0x0208 + ((x) * 10))
129 #define SI5341_IN_PSET(x)	(0x020E + ((x) * 10))
130 #define SI5341_PX_UPD		0x0230
131 
132 /* PLL configuration */
133 #define SI5341_PLL_M_NUM	0x0235
134 #define SI5341_PLL_M_DEN	0x023B
135 
136 /* Output configuration */
137 #define SI5341_OUT_CONFIG(output)	\
138 			((output)->data->reg_output_offset[(output)->index])
139 #define SI5341_OUT_FORMAT(output)	(SI5341_OUT_CONFIG(output) + 1)
140 #define SI5341_OUT_CM(output)		(SI5341_OUT_CONFIG(output) + 2)
141 #define SI5341_OUT_MUX_SEL(output)	(SI5341_OUT_CONFIG(output) + 3)
142 #define SI5341_OUT_R_REG(output)	\
143 			((output)->data->reg_rdiv_offset[(output)->index])
144 
145 #define SI5341_OUT_MUX_VDD_SEL_MASK 0x38
146 
147 /* Synthesize N divider */
148 #define SI5341_SYNTH_N_NUM(x)	(0x0302 + ((x) * 11))
149 #define SI5341_SYNTH_N_DEN(x)	(0x0308 + ((x) * 11))
150 #define SI5341_SYNTH_N_UPD(x)	(0x030C + ((x) * 11))
151 
152 /* Synthesizer output enable, phase bypass, power mode */
153 #define SI5341_SYNTH_N_CLK_TO_OUTX_EN	0x0A03
154 #define SI5341_SYNTH_N_PIBYP		0x0A04
155 #define SI5341_SYNTH_N_PDNB		0x0A05
156 #define SI5341_SYNTH_N_CLK_DIS		0x0B4A
157 
158 #define SI5341_REGISTER_MAX	0xBFF
159 
160 /* SI5341_OUT_CONFIG bits */
161 #define SI5341_OUT_CFG_PDN		BIT(0)
162 #define SI5341_OUT_CFG_OE		BIT(1)
163 #define SI5341_OUT_CFG_RDIV_FORCE2	BIT(2)
164 
165 /* Static configuration (to be moved to firmware) */
166 struct si5341_reg_default {
167 	u16 address;
168 	u8 value;
169 };
170 
171 static const char * const si5341_input_clock_names[] = {
172 	"in0", "in1", "in2", "xtal"
173 };
174 
175 /* Output configuration registers 0..9 are not quite logically organized */
176 /* Also for si5345 */
177 static const u16 si5341_reg_output_offset[] = {
178 	0x0108,
179 	0x010D,
180 	0x0112,
181 	0x0117,
182 	0x011C,
183 	0x0121,
184 	0x0126,
185 	0x012B,
186 	0x0130,
187 	0x013A,
188 };
189 
190 /* for si5340, si5342 and si5344 */
191 static const u16 si5340_reg_output_offset[] = {
192 	0x0112,
193 	0x0117,
194 	0x0126,
195 	0x012B,
196 };
197 
198 /* The location of the R divider registers */
199 static const u16 si5341_reg_rdiv_offset[] = {
200 	0x024A,
201 	0x024D,
202 	0x0250,
203 	0x0253,
204 	0x0256,
205 	0x0259,
206 	0x025C,
207 	0x025F,
208 	0x0262,
209 	0x0268,
210 };
211 static const u16 si5340_reg_rdiv_offset[] = {
212 	0x0250,
213 	0x0253,
214 	0x025C,
215 	0x025F,
216 };
217 
218 /*
219  * Programming sequence from ClockBuilder, settings to initialize the system
220  * using only the XTAL input, without pre-divider.
221  * This also contains settings that aren't mentioned anywhere in the datasheet.
222  * The "known" settings like synth and output configuration are done later.
223  */
224 static const struct si5341_reg_default si5341_reg_defaults[] = {
225 	{ 0x0017, 0x3A }, /* INT mask (disable interrupts) */
226 	{ 0x0018, 0xFF }, /* INT mask */
227 	{ 0x0021, 0x0F }, /* Select XTAL as input */
228 	{ 0x0022, 0x00 }, /* Not in datasheet */
229 	{ 0x002B, 0x02 }, /* SPI config */
230 	{ 0x002C, 0x20 }, /* LOS enable for XTAL */
231 	{ 0x002D, 0x00 }, /* LOS timing */
232 	{ 0x002E, 0x00 },
233 	{ 0x002F, 0x00 },
234 	{ 0x0030, 0x00 },
235 	{ 0x0031, 0x00 },
236 	{ 0x0032, 0x00 },
237 	{ 0x0033, 0x00 },
238 	{ 0x0034, 0x00 },
239 	{ 0x0035, 0x00 },
240 	{ 0x0036, 0x00 },
241 	{ 0x0037, 0x00 },
242 	{ 0x0038, 0x00 }, /* LOS setting (thresholds) */
243 	{ 0x0039, 0x00 },
244 	{ 0x003A, 0x00 },
245 	{ 0x003B, 0x00 },
246 	{ 0x003C, 0x00 },
247 	{ 0x003D, 0x00 }, /* LOS setting (thresholds) end */
248 	{ 0x0041, 0x00 }, /* LOS0_DIV_SEL */
249 	{ 0x0042, 0x00 }, /* LOS1_DIV_SEL */
250 	{ 0x0043, 0x00 }, /* LOS2_DIV_SEL */
251 	{ 0x0044, 0x00 }, /* LOS3_DIV_SEL */
252 	{ 0x009E, 0x00 }, /* Not in datasheet */
253 	{ 0x0102, 0x01 }, /* Enable outputs */
254 	{ 0x013F, 0x00 }, /* Not in datasheet */
255 	{ 0x0140, 0x00 }, /* Not in datasheet */
256 	{ 0x0141, 0x40 }, /* OUT LOS */
257 	{ 0x0202, 0x00 }, /* XAXB_FREQ_OFFSET (=0)*/
258 	{ 0x0203, 0x00 },
259 	{ 0x0204, 0x00 },
260 	{ 0x0205, 0x00 },
261 	{ 0x0206, 0x00 }, /* PXAXB (2^x) */
262 	{ 0x0208, 0x00 }, /* Px divider setting (usually 0) */
263 	{ 0x0209, 0x00 },
264 	{ 0x020A, 0x00 },
265 	{ 0x020B, 0x00 },
266 	{ 0x020C, 0x00 },
267 	{ 0x020D, 0x00 },
268 	{ 0x020E, 0x00 },
269 	{ 0x020F, 0x00 },
270 	{ 0x0210, 0x00 },
271 	{ 0x0211, 0x00 },
272 	{ 0x0212, 0x00 },
273 	{ 0x0213, 0x00 },
274 	{ 0x0214, 0x00 },
275 	{ 0x0215, 0x00 },
276 	{ 0x0216, 0x00 },
277 	{ 0x0217, 0x00 },
278 	{ 0x0218, 0x00 },
279 	{ 0x0219, 0x00 },
280 	{ 0x021A, 0x00 },
281 	{ 0x021B, 0x00 },
282 	{ 0x021C, 0x00 },
283 	{ 0x021D, 0x00 },
284 	{ 0x021E, 0x00 },
285 	{ 0x021F, 0x00 },
286 	{ 0x0220, 0x00 },
287 	{ 0x0221, 0x00 },
288 	{ 0x0222, 0x00 },
289 	{ 0x0223, 0x00 },
290 	{ 0x0224, 0x00 },
291 	{ 0x0225, 0x00 },
292 	{ 0x0226, 0x00 },
293 	{ 0x0227, 0x00 },
294 	{ 0x0228, 0x00 },
295 	{ 0x0229, 0x00 },
296 	{ 0x022A, 0x00 },
297 	{ 0x022B, 0x00 },
298 	{ 0x022C, 0x00 },
299 	{ 0x022D, 0x00 },
300 	{ 0x022E, 0x00 },
301 	{ 0x022F, 0x00 }, /* Px divider setting (usually 0) end */
302 	{ 0x026B, 0x00 }, /* DESIGN_ID (ASCII string) */
303 	{ 0x026C, 0x00 },
304 	{ 0x026D, 0x00 },
305 	{ 0x026E, 0x00 },
306 	{ 0x026F, 0x00 },
307 	{ 0x0270, 0x00 },
308 	{ 0x0271, 0x00 },
309 	{ 0x0272, 0x00 }, /* DESIGN_ID (ASCII string) end */
310 	{ 0x0339, 0x1F }, /* N_FSTEP_MSK */
311 	{ 0x033B, 0x00 }, /* Nx_FSTEPW (Frequency step) */
312 	{ 0x033C, 0x00 },
313 	{ 0x033D, 0x00 },
314 	{ 0x033E, 0x00 },
315 	{ 0x033F, 0x00 },
316 	{ 0x0340, 0x00 },
317 	{ 0x0341, 0x00 },
318 	{ 0x0342, 0x00 },
319 	{ 0x0343, 0x00 },
320 	{ 0x0344, 0x00 },
321 	{ 0x0345, 0x00 },
322 	{ 0x0346, 0x00 },
323 	{ 0x0347, 0x00 },
324 	{ 0x0348, 0x00 },
325 	{ 0x0349, 0x00 },
326 	{ 0x034A, 0x00 },
327 	{ 0x034B, 0x00 },
328 	{ 0x034C, 0x00 },
329 	{ 0x034D, 0x00 },
330 	{ 0x034E, 0x00 },
331 	{ 0x034F, 0x00 },
332 	{ 0x0350, 0x00 },
333 	{ 0x0351, 0x00 },
334 	{ 0x0352, 0x00 },
335 	{ 0x0353, 0x00 },
336 	{ 0x0354, 0x00 },
337 	{ 0x0355, 0x00 },
338 	{ 0x0356, 0x00 },
339 	{ 0x0357, 0x00 },
340 	{ 0x0358, 0x00 }, /* Nx_FSTEPW (Frequency step) end */
341 	{ 0x0359, 0x00 }, /* Nx_DELAY */
342 	{ 0x035A, 0x00 },
343 	{ 0x035B, 0x00 },
344 	{ 0x035C, 0x00 },
345 	{ 0x035D, 0x00 },
346 	{ 0x035E, 0x00 },
347 	{ 0x035F, 0x00 },
348 	{ 0x0360, 0x00 },
349 	{ 0x0361, 0x00 },
350 	{ 0x0362, 0x00 }, /* Nx_DELAY end */
351 	{ 0x0802, 0x00 }, /* Not in datasheet */
352 	{ 0x0803, 0x00 }, /* Not in datasheet */
353 	{ 0x0804, 0x00 }, /* Not in datasheet */
354 	{ 0x090E, 0x02 }, /* XAXB_EXTCLK_EN=0 XAXB_PDNB=1 (use XTAL) */
355 	{ 0x091C, 0x04 }, /* ZDM_EN=4 (Normal mode) */
356 	{ 0x0949, 0x00 }, /* IN_EN (disable input clocks) */
357 	{ 0x094A, 0x00 }, /* INx_TO_PFD_EN (disabled) */
358 	{ 0x0A02, 0x00 }, /* Not in datasheet */
359 	{ 0x0B44, 0x0F }, /* PDIV_ENB (datasheet does not mention what it is) */
360 	{ 0x0B57, 0x10 }, /* VCO_RESET_CALCODE (not described in datasheet) */
361 	{ 0x0B58, 0x05 }, /* VCO_RESET_CALCODE (not described in datasheet) */
362 };
363 
364 /* Read and interpret a 44-bit followed by a 32-bit value in the regmap */
365 static int si5341_decode_44_32(struct regmap *regmap, unsigned int reg,
366 	u64 *val1, u32 *val2)
367 {
368 	int err;
369 	u8 r[10];
370 
371 	err = regmap_bulk_read(regmap, reg, r, 10);
372 	if (err < 0)
373 		return err;
374 
375 	*val1 = ((u64)((r[5] & 0x0f) << 8 | r[4]) << 32) |
376 		 (get_unaligned_le32(r));
377 	*val2 = get_unaligned_le32(&r[6]);
378 
379 	return 0;
380 }
381 
382 static int si5341_encode_44_32(struct regmap *regmap, unsigned int reg,
383 	u64 n_num, u32 n_den)
384 {
385 	u8 r[10];
386 
387 	/* Shift left as far as possible without overflowing */
388 	while (!(n_num & BIT_ULL(43)) && !(n_den & BIT(31))) {
389 		n_num <<= 1;
390 		n_den <<= 1;
391 	}
392 
393 	/* 44 bits (6 bytes) numerator */
394 	put_unaligned_le32(n_num, r);
395 	r[4] = (n_num >> 32) & 0xff;
396 	r[5] = (n_num >> 40) & 0x0f;
397 	/* 32 bits denominator */
398 	put_unaligned_le32(n_den, &r[6]);
399 
400 	/* Program the fraction */
401 	return regmap_bulk_write(regmap, reg, r, sizeof(r));
402 }
403 
404 /* VCO, we assume it runs at a constant frequency */
405 static unsigned long si5341_clk_recalc_rate(struct clk_hw *hw,
406 		unsigned long parent_rate)
407 {
408 	struct clk_si5341 *data = to_clk_si5341(hw);
409 	int err;
410 	u64 res;
411 	u64 m_num;
412 	u32 m_den;
413 	unsigned int shift;
414 
415 	/* Assume that PDIV is not being used, just read the PLL setting */
416 	err = si5341_decode_44_32(data->regmap, SI5341_PLL_M_NUM,
417 				&m_num, &m_den);
418 	if (err < 0)
419 		return 0;
420 
421 	if (!m_num || !m_den)
422 		return 0;
423 
424 	/*
425 	 * Though m_num is 64-bit, only the upper bits are actually used. While
426 	 * calculating m_num and m_den, they are shifted as far as possible to
427 	 * the left. To avoid 96-bit division here, we just shift them back so
428 	 * we can do with just 64 bits.
429 	 */
430 	shift = 0;
431 	res = m_num;
432 	while (res & 0xffff00000000ULL) {
433 		++shift;
434 		res >>= 1;
435 	}
436 	res *= parent_rate;
437 	do_div(res, (m_den >> shift));
438 
439 	/* We cannot return the actual frequency in 32 bit, store it locally */
440 	data->freq_vco = res;
441 
442 	/* Report kHz since the value is out of range */
443 	do_div(res, 1000);
444 
445 	return (unsigned long)res;
446 }
447 
448 static int si5341_clk_get_selected_input(struct clk_si5341 *data)
449 {
450 	int err;
451 	u32 val;
452 
453 	err = regmap_read(data->regmap, SI5341_IN_SEL, &val);
454 	if (err < 0)
455 		return err;
456 
457 	return (val & SI5341_IN_SEL_MASK) >> SI5341_IN_SEL_SHIFT;
458 }
459 
460 static u8 si5341_clk_get_parent(struct clk_hw *hw)
461 {
462 	struct clk_si5341 *data = to_clk_si5341(hw);
463 	int res = si5341_clk_get_selected_input(data);
464 
465 	if (res < 0)
466 		return 0; /* Apparently we cannot report errors */
467 
468 	return res;
469 }
470 
471 static int si5341_clk_reparent(struct clk_si5341 *data, u8 index)
472 {
473 	int err;
474 	u8 val;
475 
476 	val = (index << SI5341_IN_SEL_SHIFT) & SI5341_IN_SEL_MASK;
477 	/* Enable register-based input selection */
478 	val |= SI5341_IN_SEL_REGCTRL;
479 
480 	err = regmap_update_bits(data->regmap,
481 		SI5341_IN_SEL, SI5341_IN_SEL_REGCTRL | SI5341_IN_SEL_MASK, val);
482 	if (err < 0)
483 		return err;
484 
485 	if (index < 3) {
486 		/* Enable input buffer for selected input */
487 		err = regmap_update_bits(data->regmap,
488 				SI5341_IN_EN, 0x07, BIT(index));
489 		if (err < 0)
490 			return err;
491 
492 		/* Enables the input to phase detector */
493 		err = regmap_update_bits(data->regmap, SI5341_INX_TO_PFD_EN,
494 				0x7 << SI5341_INX_TO_PFD_SHIFT,
495 				BIT(index + SI5341_INX_TO_PFD_SHIFT));
496 		if (err < 0)
497 			return err;
498 
499 		/* Power down XTAL oscillator and buffer */
500 		err = regmap_update_bits(data->regmap, SI5341_XAXB_CFG,
501 				SI5341_XAXB_CFG_PDNB, 0);
502 		if (err < 0)
503 			return err;
504 
505 		/*
506 		 * Set the P divider to "1". There's no explanation in the
507 		 * datasheet of these registers, but the clockbuilder software
508 		 * programs a "1" when the input is being used.
509 		 */
510 		err = regmap_write(data->regmap, SI5341_IN_PDIV(index), 1);
511 		if (err < 0)
512 			return err;
513 
514 		err = regmap_write(data->regmap, SI5341_IN_PSET(index), 1);
515 		if (err < 0)
516 			return err;
517 
518 		/* Set update PDIV bit */
519 		err = regmap_write(data->regmap, SI5341_PX_UPD, BIT(index));
520 		if (err < 0)
521 			return err;
522 	} else {
523 		/* Disable all input buffers */
524 		err = regmap_update_bits(data->regmap, SI5341_IN_EN, 0x07, 0);
525 		if (err < 0)
526 			return err;
527 
528 		/* Disable input to phase detector */
529 		err = regmap_update_bits(data->regmap, SI5341_INX_TO_PFD_EN,
530 				0x7 << SI5341_INX_TO_PFD_SHIFT, 0);
531 		if (err < 0)
532 			return err;
533 
534 		/* Power up XTAL oscillator and buffer, select clock mode */
535 		err = regmap_update_bits(data->regmap, SI5341_XAXB_CFG,
536 				SI5341_XAXB_CFG_PDNB | SI5341_XAXB_CFG_EXTCLK_EN,
537 				SI5341_XAXB_CFG_PDNB | (data->xaxb_ext_clk ?
538 					SI5341_XAXB_CFG_EXTCLK_EN : 0));
539 		if (err < 0)
540 			return err;
541 	}
542 
543 	return 0;
544 }
545 
546 static int si5341_clk_set_parent(struct clk_hw *hw, u8 index)
547 {
548 	struct clk_si5341 *data = to_clk_si5341(hw);
549 
550 	return si5341_clk_reparent(data, index);
551 }
552 
553 static const struct clk_ops si5341_clk_ops = {
554 	.set_parent = si5341_clk_set_parent,
555 	.get_parent = si5341_clk_get_parent,
556 	.recalc_rate = si5341_clk_recalc_rate,
557 };
558 
559 /* Synthesizers, there are 5 synthesizers that connect to any of the outputs */
560 
561 /* The synthesizer is on if all power and enable bits are set */
562 static int si5341_synth_clk_is_on(struct clk_hw *hw)
563 {
564 	struct clk_si5341_synth *synth = to_clk_si5341_synth(hw);
565 	int err;
566 	u32 val;
567 	u8 index = synth->index;
568 
569 	err = regmap_read(synth->data->regmap,
570 			SI5341_SYNTH_N_CLK_TO_OUTX_EN, &val);
571 	if (err < 0)
572 		return 0;
573 
574 	if (!(val & BIT(index)))
575 		return 0;
576 
577 	err = regmap_read(synth->data->regmap, SI5341_SYNTH_N_PDNB, &val);
578 	if (err < 0)
579 		return 0;
580 
581 	if (!(val & BIT(index)))
582 		return 0;
583 
584 	/* This bit must be 0 for the synthesizer to receive clock input */
585 	err = regmap_read(synth->data->regmap, SI5341_SYNTH_N_CLK_DIS, &val);
586 	if (err < 0)
587 		return 0;
588 
589 	return !(val & BIT(index));
590 }
591 
592 static void si5341_synth_clk_unprepare(struct clk_hw *hw)
593 {
594 	struct clk_si5341_synth *synth = to_clk_si5341_synth(hw);
595 	u8 index = synth->index; /* In range 0..5 */
596 	u8 mask = BIT(index);
597 
598 	/* Disable output */
599 	regmap_update_bits(synth->data->regmap,
600 		SI5341_SYNTH_N_CLK_TO_OUTX_EN, mask, 0);
601 	/* Power down */
602 	regmap_update_bits(synth->data->regmap,
603 		SI5341_SYNTH_N_PDNB, mask, 0);
604 	/* Disable clock input to synth (set to 1 to disable) */
605 	regmap_update_bits(synth->data->regmap,
606 		SI5341_SYNTH_N_CLK_DIS, mask, mask);
607 }
608 
609 static int si5341_synth_clk_prepare(struct clk_hw *hw)
610 {
611 	struct clk_si5341_synth *synth = to_clk_si5341_synth(hw);
612 	int err;
613 	u8 index = synth->index;
614 	u8 mask = BIT(index);
615 
616 	/* Power up */
617 	err = regmap_update_bits(synth->data->regmap,
618 		SI5341_SYNTH_N_PDNB, mask, mask);
619 	if (err < 0)
620 		return err;
621 
622 	/* Enable clock input to synth (set bit to 0 to enable) */
623 	err = regmap_update_bits(synth->data->regmap,
624 		SI5341_SYNTH_N_CLK_DIS, mask, 0);
625 	if (err < 0)
626 		return err;
627 
628 	/* Enable output */
629 	return regmap_update_bits(synth->data->regmap,
630 		SI5341_SYNTH_N_CLK_TO_OUTX_EN, mask, mask);
631 }
632 
633 /* Synth clock frequency: Fvco * n_den / n_den, with Fvco in 13500-14256 MHz */
634 static unsigned long si5341_synth_clk_recalc_rate(struct clk_hw *hw,
635 		unsigned long parent_rate)
636 {
637 	struct clk_si5341_synth *synth = to_clk_si5341_synth(hw);
638 	u64 f;
639 	u64 n_num;
640 	u32 n_den;
641 	int err;
642 
643 	err = si5341_decode_44_32(synth->data->regmap,
644 			SI5341_SYNTH_N_NUM(synth->index), &n_num, &n_den);
645 	if (err < 0)
646 		return err;
647 	/* Check for bogus/uninitialized settings */
648 	if (!n_num || !n_den)
649 		return 0;
650 
651 	/*
652 	 * n_num and n_den are shifted left as much as possible, so to prevent
653 	 * overflow in 64-bit math, we shift n_den 4 bits to the right
654 	 */
655 	f = synth->data->freq_vco;
656 	f *= n_den >> 4;
657 
658 	/* Now we need to to 64-bit division: f/n_num */
659 	/* And compensate for the 4 bits we dropped */
660 	f = div64_u64(f, (n_num >> 4));
661 
662 	return f;
663 }
664 
665 static long si5341_synth_clk_round_rate(struct clk_hw *hw, unsigned long rate,
666 		unsigned long *parent_rate)
667 {
668 	struct clk_si5341_synth *synth = to_clk_si5341_synth(hw);
669 	u64 f;
670 
671 	/* The synthesizer accuracy is such that anything in range will work */
672 	f = synth->data->freq_vco;
673 	do_div(f, SI5341_SYNTH_N_MAX);
674 	if (rate < f)
675 		return f;
676 
677 	f = synth->data->freq_vco;
678 	do_div(f, SI5341_SYNTH_N_MIN);
679 	if (rate > f)
680 		return f;
681 
682 	return rate;
683 }
684 
685 static int si5341_synth_program(struct clk_si5341_synth *synth,
686 	u64 n_num, u32 n_den, bool is_integer)
687 {
688 	int err;
689 	u8 index = synth->index;
690 
691 	err = si5341_encode_44_32(synth->data->regmap,
692 			SI5341_SYNTH_N_NUM(index), n_num, n_den);
693 
694 	err = regmap_update_bits(synth->data->regmap,
695 		SI5341_SYNTH_N_PIBYP, BIT(index), is_integer ? BIT(index) : 0);
696 	if (err < 0)
697 		return err;
698 
699 	return regmap_write(synth->data->regmap,
700 		SI5341_SYNTH_N_UPD(index), 0x01);
701 }
702 
703 
704 static int si5341_synth_clk_set_rate(struct clk_hw *hw, unsigned long rate,
705 		unsigned long parent_rate)
706 {
707 	struct clk_si5341_synth *synth = to_clk_si5341_synth(hw);
708 	u64 n_num;
709 	u32 n_den;
710 	u32 r;
711 	u32 g;
712 	bool is_integer;
713 
714 	n_num = synth->data->freq_vco;
715 
716 	/* see if there's an integer solution */
717 	r = do_div(n_num, rate);
718 	is_integer = (r == 0);
719 	if (is_integer) {
720 		/* Integer divider equal to n_num */
721 		n_den = 1;
722 	} else {
723 		/* Calculate a fractional solution */
724 		g = gcd(r, rate);
725 		n_den = rate / g;
726 		n_num *= n_den;
727 		n_num += r / g;
728 	}
729 
730 	dev_dbg(&synth->data->i2c_client->dev,
731 			"%s(%u): n=0x%llx d=0x%x %s\n", __func__,
732 				synth->index, n_num, n_den,
733 				is_integer ? "int" : "frac");
734 
735 	return si5341_synth_program(synth, n_num, n_den, is_integer);
736 }
737 
738 static const struct clk_ops si5341_synth_clk_ops = {
739 	.is_prepared = si5341_synth_clk_is_on,
740 	.prepare = si5341_synth_clk_prepare,
741 	.unprepare = si5341_synth_clk_unprepare,
742 	.recalc_rate = si5341_synth_clk_recalc_rate,
743 	.round_rate = si5341_synth_clk_round_rate,
744 	.set_rate = si5341_synth_clk_set_rate,
745 };
746 
747 static int si5341_output_clk_is_on(struct clk_hw *hw)
748 {
749 	struct clk_si5341_output *output = to_clk_si5341_output(hw);
750 	int err;
751 	u32 val;
752 
753 	err = regmap_read(output->data->regmap,
754 			SI5341_OUT_CONFIG(output), &val);
755 	if (err < 0)
756 		return err;
757 
758 	/* Bit 0=PDN, 1=OE so only a value of 0x2 enables the output */
759 	return (val & 0x03) == SI5341_OUT_CFG_OE;
760 }
761 
762 /* Disables and then powers down the output */
763 static void si5341_output_clk_unprepare(struct clk_hw *hw)
764 {
765 	struct clk_si5341_output *output = to_clk_si5341_output(hw);
766 
767 	regmap_update_bits(output->data->regmap,
768 			SI5341_OUT_CONFIG(output),
769 			SI5341_OUT_CFG_OE, 0);
770 	regmap_update_bits(output->data->regmap,
771 			SI5341_OUT_CONFIG(output),
772 			SI5341_OUT_CFG_PDN, SI5341_OUT_CFG_PDN);
773 }
774 
775 /* Powers up and then enables the output */
776 static int si5341_output_clk_prepare(struct clk_hw *hw)
777 {
778 	struct clk_si5341_output *output = to_clk_si5341_output(hw);
779 	int err;
780 
781 	err = regmap_update_bits(output->data->regmap,
782 			SI5341_OUT_CONFIG(output),
783 			SI5341_OUT_CFG_PDN, 0);
784 	if (err < 0)
785 		return err;
786 
787 	return regmap_update_bits(output->data->regmap,
788 			SI5341_OUT_CONFIG(output),
789 			SI5341_OUT_CFG_OE, SI5341_OUT_CFG_OE);
790 }
791 
792 static unsigned long si5341_output_clk_recalc_rate(struct clk_hw *hw,
793 		unsigned long parent_rate)
794 {
795 	struct clk_si5341_output *output = to_clk_si5341_output(hw);
796 	int err;
797 	u32 val;
798 	u32 r_divider;
799 	u8 r[3];
800 
801 	err = regmap_bulk_read(output->data->regmap,
802 			SI5341_OUT_R_REG(output), r, 3);
803 	if (err < 0)
804 		return err;
805 
806 	/* Calculate value as 24-bit integer*/
807 	r_divider = r[2] << 16 | r[1] << 8 | r[0];
808 
809 	/* If Rx_REG is zero, the divider is disabled, so return a "0" rate */
810 	if (!r_divider)
811 		return 0;
812 
813 	/* Divider is 2*(Rx_REG+1) */
814 	r_divider += 1;
815 	r_divider <<= 1;
816 
817 	err = regmap_read(output->data->regmap,
818 			SI5341_OUT_CONFIG(output), &val);
819 	if (err < 0)
820 		return err;
821 
822 	if (val & SI5341_OUT_CFG_RDIV_FORCE2)
823 		r_divider = 2;
824 
825 	return parent_rate / r_divider;
826 }
827 
828 static long si5341_output_clk_round_rate(struct clk_hw *hw, unsigned long rate,
829 		unsigned long *parent_rate)
830 {
831 	unsigned long r;
832 
833 	if (!rate)
834 		return 0;
835 
836 	r = *parent_rate >> 1;
837 
838 	/* If rate is an even divisor, no changes to parent required */
839 	if (r && !(r % rate))
840 		return (long)rate;
841 
842 	if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) {
843 		if (rate > 200000000) {
844 			/* minimum r-divider is 2 */
845 			r = 2;
846 		} else {
847 			/* Take a parent frequency near 400 MHz */
848 			r = (400000000u / rate) & ~1;
849 		}
850 		*parent_rate = r * rate;
851 	} else {
852 		/* We cannot change our parent's rate, report what we can do */
853 		r /= rate;
854 		rate = *parent_rate / (r << 1);
855 	}
856 
857 	return rate;
858 }
859 
860 static int si5341_output_clk_set_rate(struct clk_hw *hw, unsigned long rate,
861 		unsigned long parent_rate)
862 {
863 	struct clk_si5341_output *output = to_clk_si5341_output(hw);
864 	u32 r_div;
865 	int err;
866 	u8 r[3];
867 
868 	if (!rate)
869 		return -EINVAL;
870 
871 	/* Frequency divider is (r_div + 1) * 2 */
872 	r_div = (parent_rate / rate) >> 1;
873 
874 	if (r_div <= 1)
875 		r_div = 0;
876 	else if (r_div >= BIT(24))
877 		r_div = BIT(24) - 1;
878 	else
879 		--r_div;
880 
881 	/* For a value of "2", we set the "OUT0_RDIV_FORCE2" bit */
882 	err = regmap_update_bits(output->data->regmap,
883 			SI5341_OUT_CONFIG(output),
884 			SI5341_OUT_CFG_RDIV_FORCE2,
885 			(r_div == 0) ? SI5341_OUT_CFG_RDIV_FORCE2 : 0);
886 	if (err < 0)
887 		return err;
888 
889 	/* Always write Rx_REG, because a zero value disables the divider */
890 	r[0] = r_div ? (r_div & 0xff) : 1;
891 	r[1] = (r_div >> 8) & 0xff;
892 	r[2] = (r_div >> 16) & 0xff;
893 	err = regmap_bulk_write(output->data->regmap,
894 			SI5341_OUT_R_REG(output), r, 3);
895 
896 	return 0;
897 }
898 
899 static int si5341_output_reparent(struct clk_si5341_output *output, u8 index)
900 {
901 	return regmap_update_bits(output->data->regmap,
902 		SI5341_OUT_MUX_SEL(output), 0x07, index);
903 }
904 
905 static int si5341_output_set_parent(struct clk_hw *hw, u8 index)
906 {
907 	struct clk_si5341_output *output = to_clk_si5341_output(hw);
908 
909 	if (index >= output->data->num_synth)
910 		return -EINVAL;
911 
912 	return si5341_output_reparent(output, index);
913 }
914 
915 static u8 si5341_output_get_parent(struct clk_hw *hw)
916 {
917 	struct clk_si5341_output *output = to_clk_si5341_output(hw);
918 	u32 val;
919 
920 	regmap_read(output->data->regmap, SI5341_OUT_MUX_SEL(output), &val);
921 
922 	return val & 0x7;
923 }
924 
925 static const struct clk_ops si5341_output_clk_ops = {
926 	.is_prepared = si5341_output_clk_is_on,
927 	.prepare = si5341_output_clk_prepare,
928 	.unprepare = si5341_output_clk_unprepare,
929 	.recalc_rate = si5341_output_clk_recalc_rate,
930 	.round_rate = si5341_output_clk_round_rate,
931 	.set_rate = si5341_output_clk_set_rate,
932 	.set_parent = si5341_output_set_parent,
933 	.get_parent = si5341_output_get_parent,
934 };
935 
936 /*
937  * The chip can be bought in a pre-programmed version, or one can program the
938  * NVM in the chip to boot up in a preset mode. This routine tries to determine
939  * if that's the case, or if we need to reset and program everything from
940  * scratch. Returns negative error, or true/false.
941  */
942 static int si5341_is_programmed_already(struct clk_si5341 *data)
943 {
944 	int err;
945 	u8 r[4];
946 
947 	/* Read the PLL divider value, it must have a non-zero value */
948 	err = regmap_bulk_read(data->regmap, SI5341_PLL_M_DEN,
949 			r, ARRAY_SIZE(r));
950 	if (err < 0)
951 		return err;
952 
953 	return !!get_unaligned_le32(r);
954 }
955 
956 static struct clk_hw *
957 of_clk_si5341_get(struct of_phandle_args *clkspec, void *_data)
958 {
959 	struct clk_si5341 *data = _data;
960 	unsigned int idx = clkspec->args[1];
961 	unsigned int group = clkspec->args[0];
962 
963 	switch (group) {
964 	case 0:
965 		if (idx >= data->num_outputs) {
966 			dev_err(&data->i2c_client->dev,
967 				"invalid output index %u\n", idx);
968 			return ERR_PTR(-EINVAL);
969 		}
970 		return &data->clk[idx].hw;
971 	case 1:
972 		if (idx >= data->num_synth) {
973 			dev_err(&data->i2c_client->dev,
974 				"invalid synthesizer index %u\n", idx);
975 			return ERR_PTR(-EINVAL);
976 		}
977 		return &data->synth[idx].hw;
978 	case 2:
979 		if (idx > 0) {
980 			dev_err(&data->i2c_client->dev,
981 				"invalid PLL index %u\n", idx);
982 			return ERR_PTR(-EINVAL);
983 		}
984 		return &data->hw;
985 	default:
986 		dev_err(&data->i2c_client->dev, "invalid group %u\n", group);
987 		return ERR_PTR(-EINVAL);
988 	}
989 }
990 
991 static int si5341_probe_chip_id(struct clk_si5341 *data)
992 {
993 	int err;
994 	u8 reg[4];
995 	u16 model;
996 
997 	err = regmap_bulk_read(data->regmap, SI5341_PN_BASE, reg,
998 				ARRAY_SIZE(reg));
999 	if (err < 0) {
1000 		dev_err(&data->i2c_client->dev, "Failed to read chip ID\n");
1001 		return err;
1002 	}
1003 
1004 	model = get_unaligned_le16(reg);
1005 
1006 	dev_info(&data->i2c_client->dev, "Chip: %x Grade: %u Rev: %u\n",
1007 		 model, reg[2], reg[3]);
1008 
1009 	switch (model) {
1010 	case 0x5340:
1011 		data->num_outputs = SI5340_MAX_NUM_OUTPUTS;
1012 		data->num_synth = SI5340_NUM_SYNTH;
1013 		data->reg_output_offset = si5340_reg_output_offset;
1014 		data->reg_rdiv_offset = si5340_reg_rdiv_offset;
1015 		break;
1016 	case 0x5341:
1017 		data->num_outputs = SI5341_MAX_NUM_OUTPUTS;
1018 		data->num_synth = SI5341_NUM_SYNTH;
1019 		data->reg_output_offset = si5341_reg_output_offset;
1020 		data->reg_rdiv_offset = si5341_reg_rdiv_offset;
1021 		break;
1022 	case 0x5342:
1023 		data->num_outputs = SI5342_MAX_NUM_OUTPUTS;
1024 		data->num_synth = SI5342_NUM_SYNTH;
1025 		data->reg_output_offset = si5340_reg_output_offset;
1026 		data->reg_rdiv_offset = si5340_reg_rdiv_offset;
1027 		break;
1028 	case 0x5344:
1029 		data->num_outputs = SI5344_MAX_NUM_OUTPUTS;
1030 		data->num_synth = SI5344_NUM_SYNTH;
1031 		data->reg_output_offset = si5340_reg_output_offset;
1032 		data->reg_rdiv_offset = si5340_reg_rdiv_offset;
1033 		break;
1034 	case 0x5345:
1035 		data->num_outputs = SI5345_MAX_NUM_OUTPUTS;
1036 		data->num_synth = SI5345_NUM_SYNTH;
1037 		data->reg_output_offset = si5341_reg_output_offset;
1038 		data->reg_rdiv_offset = si5341_reg_rdiv_offset;
1039 		break;
1040 	default:
1041 		dev_err(&data->i2c_client->dev, "Model '%x' not supported\n",
1042 			model);
1043 		return -EINVAL;
1044 	}
1045 
1046 	data->chip_id = model;
1047 
1048 	return 0;
1049 }
1050 
1051 /* Read active settings into the regmap cache for later reference */
1052 static int si5341_read_settings(struct clk_si5341 *data)
1053 {
1054 	int err;
1055 	u8 i;
1056 	u8 r[10];
1057 
1058 	err = regmap_bulk_read(data->regmap, SI5341_PLL_M_NUM, r, 10);
1059 	if (err < 0)
1060 		return err;
1061 
1062 	err = regmap_bulk_read(data->regmap,
1063 				SI5341_SYNTH_N_CLK_TO_OUTX_EN, r, 3);
1064 	if (err < 0)
1065 		return err;
1066 
1067 	err = regmap_bulk_read(data->regmap,
1068 				SI5341_SYNTH_N_CLK_DIS, r, 1);
1069 	if (err < 0)
1070 		return err;
1071 
1072 	for (i = 0; i < data->num_synth; ++i) {
1073 		err = regmap_bulk_read(data->regmap,
1074 					SI5341_SYNTH_N_NUM(i), r, 10);
1075 		if (err < 0)
1076 			return err;
1077 	}
1078 
1079 	for (i = 0; i < data->num_outputs; ++i) {
1080 		err = regmap_bulk_read(data->regmap,
1081 					data->reg_output_offset[i], r, 4);
1082 		if (err < 0)
1083 			return err;
1084 
1085 		err = regmap_bulk_read(data->regmap,
1086 					data->reg_rdiv_offset[i], r, 3);
1087 		if (err < 0)
1088 			return err;
1089 	}
1090 
1091 	return 0;
1092 }
1093 
1094 static int si5341_write_multiple(struct clk_si5341 *data,
1095 	const struct si5341_reg_default *values, unsigned int num_values)
1096 {
1097 	unsigned int i;
1098 	int res;
1099 
1100 	for (i = 0; i < num_values; ++i) {
1101 		res = regmap_write(data->regmap,
1102 			values[i].address, values[i].value);
1103 		if (res < 0) {
1104 			dev_err(&data->i2c_client->dev,
1105 				"Failed to write %#x:%#x\n",
1106 				values[i].address, values[i].value);
1107 			return res;
1108 		}
1109 	}
1110 
1111 	return 0;
1112 }
1113 
1114 static const struct si5341_reg_default si5341_preamble[] = {
1115 	{ 0x0B25, 0x00 },
1116 	{ 0x0502, 0x01 },
1117 	{ 0x0505, 0x03 },
1118 	{ 0x0957, 0x17 },
1119 	{ 0x0B4E, 0x1A },
1120 };
1121 
1122 static const struct si5341_reg_default si5345_preamble[] = {
1123 	{ 0x0B25, 0x00 },
1124 	{ 0x0540, 0x01 },
1125 };
1126 
1127 static int si5341_send_preamble(struct clk_si5341 *data)
1128 {
1129 	int res;
1130 	u32 revision;
1131 
1132 	/* For revision 2 and up, the values are slightly different */
1133 	res = regmap_read(data->regmap, SI5341_DEVICE_REV, &revision);
1134 	if (res < 0)
1135 		return res;
1136 
1137 	/* Write "preamble" as specified by datasheet */
1138 	res = regmap_write(data->regmap, 0xB24, revision < 2 ? 0xD8 : 0xC0);
1139 	if (res < 0)
1140 		return res;
1141 
1142 	/* The si5342..si5345 require a different preamble */
1143 	if (data->chip_id > 0x5341)
1144 		res = si5341_write_multiple(data,
1145 			si5345_preamble, ARRAY_SIZE(si5345_preamble));
1146 	else
1147 		res = si5341_write_multiple(data,
1148 			si5341_preamble, ARRAY_SIZE(si5341_preamble));
1149 	if (res < 0)
1150 		return res;
1151 
1152 	/* Datasheet specifies a 300ms wait after sending the preamble */
1153 	msleep(300);
1154 
1155 	return 0;
1156 }
1157 
1158 /* Perform a soft reset and write post-amble */
1159 static int si5341_finalize_defaults(struct clk_si5341 *data)
1160 {
1161 	int res;
1162 	u32 revision;
1163 
1164 	res = regmap_write(data->regmap, SI5341_IO_VDD_SEL,
1165 			   data->iovdd_33 ? 1 : 0);
1166 	if (res < 0)
1167 		return res;
1168 
1169 	res = regmap_read(data->regmap, SI5341_DEVICE_REV, &revision);
1170 	if (res < 0)
1171 		return res;
1172 
1173 	dev_dbg(&data->i2c_client->dev, "%s rev=%u\n", __func__, revision);
1174 
1175 	res = regmap_write(data->regmap, SI5341_SOFT_RST, 0x01);
1176 	if (res < 0)
1177 		return res;
1178 
1179 	/* The si5342..si5345 have an additional post-amble */
1180 	if (data->chip_id > 0x5341) {
1181 		res = regmap_write(data->regmap, 0x540, 0x0);
1182 		if (res < 0)
1183 			return res;
1184 	}
1185 
1186 	/* Datasheet does not explain these nameless registers */
1187 	res = regmap_write(data->regmap, 0xB24, revision < 2 ? 0xDB : 0xC3);
1188 	if (res < 0)
1189 		return res;
1190 	res = regmap_write(data->regmap, 0x0B25, 0x02);
1191 	if (res < 0)
1192 		return res;
1193 
1194 	return 0;
1195 }
1196 
1197 
1198 static const struct regmap_range si5341_regmap_volatile_range[] = {
1199 	regmap_reg_range(0x000C, 0x0012), /* Status */
1200 	regmap_reg_range(0x001C, 0x001E), /* reset, finc/fdec */
1201 	regmap_reg_range(0x00E2, 0x00FE), /* NVM, interrupts, device ready */
1202 	/* Update bits for P divider and synth config */
1203 	regmap_reg_range(SI5341_PX_UPD, SI5341_PX_UPD),
1204 	regmap_reg_range(SI5341_SYNTH_N_UPD(0), SI5341_SYNTH_N_UPD(0)),
1205 	regmap_reg_range(SI5341_SYNTH_N_UPD(1), SI5341_SYNTH_N_UPD(1)),
1206 	regmap_reg_range(SI5341_SYNTH_N_UPD(2), SI5341_SYNTH_N_UPD(2)),
1207 	regmap_reg_range(SI5341_SYNTH_N_UPD(3), SI5341_SYNTH_N_UPD(3)),
1208 	regmap_reg_range(SI5341_SYNTH_N_UPD(4), SI5341_SYNTH_N_UPD(4)),
1209 };
1210 
1211 static const struct regmap_access_table si5341_regmap_volatile = {
1212 	.yes_ranges = si5341_regmap_volatile_range,
1213 	.n_yes_ranges = ARRAY_SIZE(si5341_regmap_volatile_range),
1214 };
1215 
1216 /* Pages 0, 1, 2, 3, 9, A, B are valid, so there are 12 pages */
1217 static const struct regmap_range_cfg si5341_regmap_ranges[] = {
1218 	{
1219 		.range_min = 0,
1220 		.range_max = SI5341_REGISTER_MAX,
1221 		.selector_reg = SI5341_PAGE,
1222 		.selector_mask = 0xff,
1223 		.selector_shift = 0,
1224 		.window_start = 0,
1225 		.window_len = 256,
1226 	},
1227 };
1228 
1229 static int si5341_wait_device_ready(struct i2c_client *client)
1230 {
1231 	int count;
1232 
1233 	/* Datasheet warns: Any attempt to read or write any register other
1234 	 * than DEVICE_READY before DEVICE_READY reads as 0x0F may corrupt the
1235 	 * NVM programming and may corrupt the register contents, as they are
1236 	 * read from NVM. Note that this includes accesses to the PAGE register.
1237 	 * Also: DEVICE_READY is available on every register page, so no page
1238 	 * change is needed to read it.
1239 	 * Do this outside regmap to avoid automatic PAGE register access.
1240 	 * May take up to 300ms to complete.
1241 	 */
1242 	for (count = 0; count < 15; ++count) {
1243 		s32 result = i2c_smbus_read_byte_data(client,
1244 						      SI5341_DEVICE_READY);
1245 		if (result < 0)
1246 			return result;
1247 		if (result == 0x0F)
1248 			return 0;
1249 		msleep(20);
1250 	}
1251 	dev_err(&client->dev, "timeout waiting for DEVICE_READY\n");
1252 	return -EIO;
1253 }
1254 
1255 static const struct regmap_config si5341_regmap_config = {
1256 	.reg_bits = 8,
1257 	.val_bits = 8,
1258 	.cache_type = REGCACHE_RBTREE,
1259 	.ranges = si5341_regmap_ranges,
1260 	.num_ranges = ARRAY_SIZE(si5341_regmap_ranges),
1261 	.max_register = SI5341_REGISTER_MAX,
1262 	.volatile_table = &si5341_regmap_volatile,
1263 };
1264 
1265 static int si5341_dt_parse_dt(struct clk_si5341 *data,
1266 			      struct clk_si5341_output_config *config)
1267 {
1268 	struct device_node *child;
1269 	struct device_node *np = data->i2c_client->dev.of_node;
1270 	u32 num;
1271 	u32 val;
1272 
1273 	memset(config, 0, sizeof(struct clk_si5341_output_config) *
1274 				SI5341_MAX_NUM_OUTPUTS);
1275 
1276 	for_each_child_of_node(np, child) {
1277 		if (of_property_read_u32(child, "reg", &num)) {
1278 			dev_err(&data->i2c_client->dev, "missing reg property of %s\n",
1279 				child->name);
1280 			goto put_child;
1281 		}
1282 
1283 		if (num >= SI5341_MAX_NUM_OUTPUTS) {
1284 			dev_err(&data->i2c_client->dev, "invalid clkout %d\n", num);
1285 			goto put_child;
1286 		}
1287 
1288 		if (!of_property_read_u32(child, "silabs,format", &val)) {
1289 			/* Set cm and ampl conservatively to 3v3 settings */
1290 			switch (val) {
1291 			case 1: /* normal differential */
1292 				config[num].out_cm_ampl_bits = 0x33;
1293 				break;
1294 			case 2: /* low-power differential */
1295 				config[num].out_cm_ampl_bits = 0x13;
1296 				break;
1297 			case 4: /* LVCMOS */
1298 				config[num].out_cm_ampl_bits = 0x33;
1299 				/* Set SI recommended impedance for LVCMOS */
1300 				config[num].out_format_drv_bits |= 0xc0;
1301 				break;
1302 			default:
1303 				dev_err(&data->i2c_client->dev,
1304 					"invalid silabs,format %u for %u\n",
1305 					val, num);
1306 				goto put_child;
1307 			}
1308 			config[num].out_format_drv_bits &= ~0x07;
1309 			config[num].out_format_drv_bits |= val & 0x07;
1310 			/* Always enable the SYNC feature */
1311 			config[num].out_format_drv_bits |= 0x08;
1312 		}
1313 
1314 		if (!of_property_read_u32(child, "silabs,common-mode", &val)) {
1315 			if (val > 0xf) {
1316 				dev_err(&data->i2c_client->dev,
1317 					"invalid silabs,common-mode %u\n",
1318 					val);
1319 				goto put_child;
1320 			}
1321 			config[num].out_cm_ampl_bits &= 0xf0;
1322 			config[num].out_cm_ampl_bits |= val & 0x0f;
1323 		}
1324 
1325 		if (!of_property_read_u32(child, "silabs,amplitude", &val)) {
1326 			if (val > 0xf) {
1327 				dev_err(&data->i2c_client->dev,
1328 					"invalid silabs,amplitude %u\n",
1329 					val);
1330 				goto put_child;
1331 			}
1332 			config[num].out_cm_ampl_bits &= 0x0f;
1333 			config[num].out_cm_ampl_bits |= (val << 4) & 0xf0;
1334 		}
1335 
1336 		if (of_property_read_bool(child, "silabs,disable-high"))
1337 			config[num].out_format_drv_bits |= 0x10;
1338 
1339 		config[num].synth_master =
1340 			of_property_read_bool(child, "silabs,synth-master");
1341 
1342 		config[num].always_on =
1343 			of_property_read_bool(child, "always-on");
1344 
1345 		config[num].vdd_sel_bits = 0x08;
1346 		if (data->clk[num].vddo_reg) {
1347 			int vdd = regulator_get_voltage(data->clk[num].vddo_reg);
1348 
1349 			switch (vdd) {
1350 			case 3300000:
1351 				config[num].vdd_sel_bits |= 0 << 4;
1352 				break;
1353 			case 1800000:
1354 				config[num].vdd_sel_bits |= 1 << 4;
1355 				break;
1356 			case 2500000:
1357 				config[num].vdd_sel_bits |= 2 << 4;
1358 				break;
1359 			default:
1360 				dev_err(&data->i2c_client->dev,
1361 					"unsupported vddo voltage %d for %s\n",
1362 					vdd, child->name);
1363 				goto put_child;
1364 			}
1365 		} else {
1366 			/* chip seems to default to 2.5V when not set */
1367 			dev_warn(&data->i2c_client->dev,
1368 				"no regulator set, defaulting vdd_sel to 2.5V for %s\n",
1369 				child->name);
1370 			config[num].vdd_sel_bits |= 2 << 4;
1371 		}
1372 	}
1373 
1374 	return 0;
1375 
1376 put_child:
1377 	of_node_put(child);
1378 	return -EINVAL;
1379 }
1380 
1381 /*
1382  * If not pre-configured, calculate and set the PLL configuration manually.
1383  * For low-jitter performance, the PLL should be set such that the synthesizers
1384  * only need integer division.
1385  * Without any user guidance, we'll set the PLL to 14GHz, which still allows
1386  * the chip to generate any frequency on its outputs, but jitter performance
1387  * may be sub-optimal.
1388  */
1389 static int si5341_initialize_pll(struct clk_si5341 *data)
1390 {
1391 	struct device_node *np = data->i2c_client->dev.of_node;
1392 	u32 m_num = 0;
1393 	u32 m_den = 0;
1394 	int sel;
1395 
1396 	if (of_property_read_u32(np, "silabs,pll-m-num", &m_num)) {
1397 		dev_err(&data->i2c_client->dev,
1398 			"PLL configuration requires silabs,pll-m-num\n");
1399 	}
1400 	if (of_property_read_u32(np, "silabs,pll-m-den", &m_den)) {
1401 		dev_err(&data->i2c_client->dev,
1402 			"PLL configuration requires silabs,pll-m-den\n");
1403 	}
1404 
1405 	if (!m_num || !m_den) {
1406 		dev_err(&data->i2c_client->dev,
1407 			"PLL configuration invalid, assume 14GHz\n");
1408 		sel = si5341_clk_get_selected_input(data);
1409 		if (sel < 0)
1410 			return sel;
1411 
1412 		m_den = clk_get_rate(data->input_clk[sel]) / 10;
1413 		m_num = 1400000000;
1414 	}
1415 
1416 	return si5341_encode_44_32(data->regmap,
1417 			SI5341_PLL_M_NUM, m_num, m_den);
1418 }
1419 
1420 static int si5341_clk_select_active_input(struct clk_si5341 *data)
1421 {
1422 	int res;
1423 	int err;
1424 	int i;
1425 
1426 	res = si5341_clk_get_selected_input(data);
1427 	if (res < 0)
1428 		return res;
1429 
1430 	/* If the current register setting is invalid, pick the first input */
1431 	if (!data->input_clk[res]) {
1432 		dev_dbg(&data->i2c_client->dev,
1433 			"Input %d not connected, rerouting\n", res);
1434 		res = -ENODEV;
1435 		for (i = 0; i < SI5341_NUM_INPUTS; ++i) {
1436 			if (data->input_clk[i]) {
1437 				res = i;
1438 				break;
1439 			}
1440 		}
1441 		if (res < 0) {
1442 			dev_err(&data->i2c_client->dev,
1443 				"No clock input available\n");
1444 			return res;
1445 		}
1446 	}
1447 
1448 	/* Make sure the selected clock is also enabled and routed */
1449 	err = si5341_clk_reparent(data, res);
1450 	if (err < 0)
1451 		return err;
1452 
1453 	err = clk_prepare_enable(data->input_clk[res]);
1454 	if (err < 0)
1455 		return err;
1456 
1457 	return res;
1458 }
1459 
1460 static ssize_t input_present_show(struct device *dev,
1461 				  struct device_attribute *attr,
1462 				  char *buf)
1463 {
1464 	struct clk_si5341 *data = dev_get_drvdata(dev);
1465 	u32 status;
1466 	int res = regmap_read(data->regmap, SI5341_STATUS, &status);
1467 
1468 	if (res < 0)
1469 		return res;
1470 	res = !(status & SI5341_STATUS_LOSREF);
1471 	return snprintf(buf, PAGE_SIZE, "%d\n", res);
1472 }
1473 static DEVICE_ATTR_RO(input_present);
1474 
1475 static ssize_t input_present_sticky_show(struct device *dev,
1476 					 struct device_attribute *attr,
1477 					 char *buf)
1478 {
1479 	struct clk_si5341 *data = dev_get_drvdata(dev);
1480 	u32 status;
1481 	int res = regmap_read(data->regmap, SI5341_STATUS_STICKY, &status);
1482 
1483 	if (res < 0)
1484 		return res;
1485 	res = !(status & SI5341_STATUS_LOSREF);
1486 	return snprintf(buf, PAGE_SIZE, "%d\n", res);
1487 }
1488 static DEVICE_ATTR_RO(input_present_sticky);
1489 
1490 static ssize_t pll_locked_show(struct device *dev,
1491 			       struct device_attribute *attr,
1492 			       char *buf)
1493 {
1494 	struct clk_si5341 *data = dev_get_drvdata(dev);
1495 	u32 status;
1496 	int res = regmap_read(data->regmap, SI5341_STATUS, &status);
1497 
1498 	if (res < 0)
1499 		return res;
1500 	res = !(status & SI5341_STATUS_LOL);
1501 	return snprintf(buf, PAGE_SIZE, "%d\n", res);
1502 }
1503 static DEVICE_ATTR_RO(pll_locked);
1504 
1505 static ssize_t pll_locked_sticky_show(struct device *dev,
1506 				      struct device_attribute *attr,
1507 				      char *buf)
1508 {
1509 	struct clk_si5341 *data = dev_get_drvdata(dev);
1510 	u32 status;
1511 	int res = regmap_read(data->regmap, SI5341_STATUS_STICKY, &status);
1512 
1513 	if (res < 0)
1514 		return res;
1515 	res = !(status & SI5341_STATUS_LOL);
1516 	return snprintf(buf, PAGE_SIZE, "%d\n", res);
1517 }
1518 static DEVICE_ATTR_RO(pll_locked_sticky);
1519 
1520 static ssize_t clear_sticky_store(struct device *dev,
1521 				  struct device_attribute *attr,
1522 				  const char *buf, size_t count)
1523 {
1524 	struct clk_si5341 *data = dev_get_drvdata(dev);
1525 	long val;
1526 
1527 	if (kstrtol(buf, 10, &val))
1528 		return -EINVAL;
1529 	if (val) {
1530 		int res = regmap_write(data->regmap, SI5341_STATUS_STICKY, 0);
1531 
1532 		if (res < 0)
1533 			return res;
1534 	}
1535 	return count;
1536 }
1537 static DEVICE_ATTR_WO(clear_sticky);
1538 
1539 static const struct attribute *si5341_attributes[] = {
1540 	&dev_attr_input_present.attr,
1541 	&dev_attr_input_present_sticky.attr,
1542 	&dev_attr_pll_locked.attr,
1543 	&dev_attr_pll_locked_sticky.attr,
1544 	&dev_attr_clear_sticky.attr,
1545 	NULL
1546 };
1547 
1548 static int si5341_probe(struct i2c_client *client,
1549 		const struct i2c_device_id *id)
1550 {
1551 	struct clk_si5341 *data;
1552 	struct clk_init_data init;
1553 	struct clk *input;
1554 	const char *root_clock_name;
1555 	const char *synth_clock_names[SI5341_NUM_SYNTH];
1556 	int err;
1557 	unsigned int i;
1558 	struct clk_si5341_output_config config[SI5341_MAX_NUM_OUTPUTS];
1559 	bool initialization_required;
1560 	u32 status;
1561 
1562 	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
1563 	if (!data)
1564 		return -ENOMEM;
1565 
1566 	data->i2c_client = client;
1567 
1568 	/* Must be done before otherwise touching hardware */
1569 	err = si5341_wait_device_ready(client);
1570 	if (err)
1571 		return err;
1572 
1573 	for (i = 0; i < SI5341_NUM_INPUTS; ++i) {
1574 		input = devm_clk_get(&client->dev, si5341_input_clock_names[i]);
1575 		if (IS_ERR(input)) {
1576 			if (PTR_ERR(input) == -EPROBE_DEFER)
1577 				return -EPROBE_DEFER;
1578 			data->input_clk_name[i] = si5341_input_clock_names[i];
1579 		} else {
1580 			data->input_clk[i] = input;
1581 			data->input_clk_name[i] = __clk_get_name(input);
1582 		}
1583 	}
1584 
1585 	for (i = 0; i < SI5341_MAX_NUM_OUTPUTS; ++i) {
1586 		char reg_name[10];
1587 
1588 		snprintf(reg_name, sizeof(reg_name), "vddo%d", i);
1589 		data->clk[i].vddo_reg = devm_regulator_get_optional(
1590 			&client->dev, reg_name);
1591 		if (IS_ERR(data->clk[i].vddo_reg)) {
1592 			err = PTR_ERR(data->clk[i].vddo_reg);
1593 			data->clk[i].vddo_reg = NULL;
1594 			if (err == -ENODEV)
1595 				continue;
1596 			goto cleanup;
1597 		} else {
1598 			err = regulator_enable(data->clk[i].vddo_reg);
1599 			if (err) {
1600 				dev_err(&client->dev,
1601 					"failed to enable %s regulator: %d\n",
1602 					reg_name, err);
1603 				data->clk[i].vddo_reg = NULL;
1604 				goto cleanup;
1605 			}
1606 		}
1607 	}
1608 
1609 	err = si5341_dt_parse_dt(data, config);
1610 	if (err)
1611 		goto cleanup;
1612 
1613 	if (of_property_read_string(client->dev.of_node, "clock-output-names",
1614 			&init.name))
1615 		init.name = client->dev.of_node->name;
1616 	root_clock_name = init.name;
1617 
1618 	data->regmap = devm_regmap_init_i2c(client, &si5341_regmap_config);
1619 	if (IS_ERR(data->regmap)) {
1620 		err = PTR_ERR(data->regmap);
1621 		goto cleanup;
1622 	}
1623 
1624 	i2c_set_clientdata(client, data);
1625 
1626 	err = si5341_probe_chip_id(data);
1627 	if (err < 0)
1628 		goto cleanup;
1629 
1630 	if (of_property_read_bool(client->dev.of_node, "silabs,reprogram")) {
1631 		initialization_required = true;
1632 	} else {
1633 		err = si5341_is_programmed_already(data);
1634 		if (err < 0)
1635 			goto cleanup;
1636 
1637 		initialization_required = !err;
1638 	}
1639 	data->xaxb_ext_clk = of_property_read_bool(client->dev.of_node,
1640 						   "silabs,xaxb-ext-clk");
1641 	data->iovdd_33 = of_property_read_bool(client->dev.of_node,
1642 					       "silabs,iovdd-33");
1643 
1644 	if (initialization_required) {
1645 		/* Populate the regmap cache in preparation for "cache only" */
1646 		err = si5341_read_settings(data);
1647 		if (err < 0)
1648 			goto cleanup;
1649 
1650 		err = si5341_send_preamble(data);
1651 		if (err < 0)
1652 			goto cleanup;
1653 
1654 		/*
1655 		 * We intend to send all 'final' register values in a single
1656 		 * transaction. So cache all register writes until we're done
1657 		 * configuring.
1658 		 */
1659 		regcache_cache_only(data->regmap, true);
1660 
1661 		/* Write the configuration pairs from the firmware blob */
1662 		err = si5341_write_multiple(data, si5341_reg_defaults,
1663 					ARRAY_SIZE(si5341_reg_defaults));
1664 		if (err < 0)
1665 			goto cleanup;
1666 	}
1667 
1668 	/* Input must be up and running at this point */
1669 	err = si5341_clk_select_active_input(data);
1670 	if (err < 0)
1671 		goto cleanup;
1672 
1673 	if (initialization_required) {
1674 		/* PLL configuration is required */
1675 		err = si5341_initialize_pll(data);
1676 		if (err < 0)
1677 			goto cleanup;
1678 	}
1679 
1680 	/* Register the PLL */
1681 	init.parent_names = data->input_clk_name;
1682 	init.num_parents = SI5341_NUM_INPUTS;
1683 	init.ops = &si5341_clk_ops;
1684 	init.flags = 0;
1685 	data->hw.init = &init;
1686 
1687 	err = devm_clk_hw_register(&client->dev, &data->hw);
1688 	if (err) {
1689 		dev_err(&client->dev, "clock registration failed\n");
1690 		goto cleanup;
1691 	}
1692 
1693 	init.num_parents = 1;
1694 	init.parent_names = &root_clock_name;
1695 	init.ops = &si5341_synth_clk_ops;
1696 	for (i = 0; i < data->num_synth; ++i) {
1697 		synth_clock_names[i] = devm_kasprintf(&client->dev, GFP_KERNEL,
1698 				"%s.N%u", client->dev.of_node->name, i);
1699 		init.name = synth_clock_names[i];
1700 		data->synth[i].index = i;
1701 		data->synth[i].data = data;
1702 		data->synth[i].hw.init = &init;
1703 		err = devm_clk_hw_register(&client->dev, &data->synth[i].hw);
1704 		if (err) {
1705 			dev_err(&client->dev,
1706 				"synth N%u registration failed\n", i);
1707 		}
1708 	}
1709 
1710 	init.num_parents = data->num_synth;
1711 	init.parent_names = synth_clock_names;
1712 	init.ops = &si5341_output_clk_ops;
1713 	for (i = 0; i < data->num_outputs; ++i) {
1714 		init.name = kasprintf(GFP_KERNEL, "%s.%d",
1715 			client->dev.of_node->name, i);
1716 		init.flags = config[i].synth_master ? CLK_SET_RATE_PARENT : 0;
1717 		data->clk[i].index = i;
1718 		data->clk[i].data = data;
1719 		data->clk[i].hw.init = &init;
1720 		if (config[i].out_format_drv_bits & 0x07) {
1721 			regmap_write(data->regmap,
1722 				SI5341_OUT_FORMAT(&data->clk[i]),
1723 				config[i].out_format_drv_bits);
1724 			regmap_write(data->regmap,
1725 				SI5341_OUT_CM(&data->clk[i]),
1726 				config[i].out_cm_ampl_bits);
1727 			regmap_update_bits(data->regmap,
1728 				SI5341_OUT_MUX_SEL(&data->clk[i]),
1729 				SI5341_OUT_MUX_VDD_SEL_MASK,
1730 				config[i].vdd_sel_bits);
1731 		}
1732 		err = devm_clk_hw_register(&client->dev, &data->clk[i].hw);
1733 		kfree(init.name); /* clock framework made a copy of the name */
1734 		if (err) {
1735 			dev_err(&client->dev,
1736 				"output %u registration failed\n", i);
1737 			goto cleanup;
1738 		}
1739 		if (config[i].always_on)
1740 			clk_prepare(data->clk[i].hw.clk);
1741 	}
1742 
1743 	err = of_clk_add_hw_provider(client->dev.of_node, of_clk_si5341_get,
1744 			data);
1745 	if (err) {
1746 		dev_err(&client->dev, "unable to add clk provider\n");
1747 		goto cleanup;
1748 	}
1749 
1750 	if (initialization_required) {
1751 		/* Synchronize */
1752 		regcache_cache_only(data->regmap, false);
1753 		err = regcache_sync(data->regmap);
1754 		if (err < 0)
1755 			goto cleanup;
1756 
1757 		err = si5341_finalize_defaults(data);
1758 		if (err < 0)
1759 			goto cleanup;
1760 	}
1761 
1762 	/* wait for device to report input clock present and PLL lock */
1763 	err = regmap_read_poll_timeout(data->regmap, SI5341_STATUS, status,
1764 		!(status & (SI5341_STATUS_LOSREF | SI5341_STATUS_LOL)),
1765 	       10000, 250000);
1766 	if (err) {
1767 		dev_err(&client->dev, "Error waiting for input clock or PLL lock\n");
1768 		goto cleanup;
1769 	}
1770 
1771 	/* clear sticky alarm bits from initialization */
1772 	err = regmap_write(data->regmap, SI5341_STATUS_STICKY, 0);
1773 	if (err) {
1774 		dev_err(&client->dev, "unable to clear sticky status\n");
1775 		goto cleanup;
1776 	}
1777 
1778 	err = sysfs_create_files(&client->dev.kobj, si5341_attributes);
1779 	if (err) {
1780 		dev_err(&client->dev, "unable to create sysfs files\n");
1781 		goto cleanup;
1782 	}
1783 
1784 	/* Free the names, clk framework makes copies */
1785 	for (i = 0; i < data->num_synth; ++i)
1786 		 devm_kfree(&client->dev, (void *)synth_clock_names[i]);
1787 
1788 	return 0;
1789 
1790 cleanup:
1791 	for (i = 0; i < SI5341_MAX_NUM_OUTPUTS; ++i) {
1792 		if (data->clk[i].vddo_reg)
1793 			regulator_disable(data->clk[i].vddo_reg);
1794 	}
1795 	return err;
1796 }
1797 
1798 static int si5341_remove(struct i2c_client *client)
1799 {
1800 	struct clk_si5341 *data = i2c_get_clientdata(client);
1801 	int i;
1802 
1803 	sysfs_remove_files(&client->dev.kobj, si5341_attributes);
1804 
1805 	for (i = 0; i < SI5341_MAX_NUM_OUTPUTS; ++i) {
1806 		if (data->clk[i].vddo_reg)
1807 			regulator_disable(data->clk[i].vddo_reg);
1808 	}
1809 
1810 	return 0;
1811 }
1812 
1813 static const struct i2c_device_id si5341_id[] = {
1814 	{ "si5340", 0 },
1815 	{ "si5341", 1 },
1816 	{ "si5342", 2 },
1817 	{ "si5344", 4 },
1818 	{ "si5345", 5 },
1819 	{ }
1820 };
1821 MODULE_DEVICE_TABLE(i2c, si5341_id);
1822 
1823 static const struct of_device_id clk_si5341_of_match[] = {
1824 	{ .compatible = "silabs,si5340" },
1825 	{ .compatible = "silabs,si5341" },
1826 	{ .compatible = "silabs,si5342" },
1827 	{ .compatible = "silabs,si5344" },
1828 	{ .compatible = "silabs,si5345" },
1829 	{ }
1830 };
1831 MODULE_DEVICE_TABLE(of, clk_si5341_of_match);
1832 
1833 static struct i2c_driver si5341_driver = {
1834 	.driver = {
1835 		.name = "si5341",
1836 		.of_match_table = clk_si5341_of_match,
1837 	},
1838 	.probe		= si5341_probe,
1839 	.remove		= si5341_remove,
1840 	.id_table	= si5341_id,
1841 };
1842 module_i2c_driver(si5341_driver);
1843 
1844 MODULE_AUTHOR("Mike Looijmans <mike.looijmans@topic.nl>");
1845 MODULE_DESCRIPTION("Si5341 driver");
1846 MODULE_LICENSE("GPL");
1847