xref: /openbmc/linux/drivers/clk/clk-si5341.c (revision 4b33b5ff)
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 do 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_read(output->data->regmap,
802 			SI5341_OUT_CONFIG(output), &val);
803 	if (err < 0)
804 		return err;
805 
806 	/* If SI5341_OUT_CFG_RDIV_FORCE2 is set, r_divider is 2 */
807 	if (val & SI5341_OUT_CFG_RDIV_FORCE2)
808 		return parent_rate / 2;
809 
810 	err = regmap_bulk_read(output->data->regmap,
811 			SI5341_OUT_R_REG(output), r, 3);
812 	if (err < 0)
813 		return err;
814 
815 	/* Calculate value as 24-bit integer*/
816 	r_divider = r[2] << 16 | r[1] << 8 | r[0];
817 
818 	/* If Rx_REG is zero, the divider is disabled, so return a "0" rate */
819 	if (!r_divider)
820 		return 0;
821 
822 	/* Divider is 2*(Rx_REG+1) */
823 	r_divider += 1;
824 	r_divider <<= 1;
825 
826 
827 	return parent_rate / r_divider;
828 }
829 
830 static long si5341_output_clk_round_rate(struct clk_hw *hw, unsigned long rate,
831 		unsigned long *parent_rate)
832 {
833 	unsigned long r;
834 
835 	if (!rate)
836 		return 0;
837 
838 	r = *parent_rate >> 1;
839 
840 	/* If rate is an even divisor, no changes to parent required */
841 	if (r && !(r % rate))
842 		return (long)rate;
843 
844 	if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) {
845 		if (rate > 200000000) {
846 			/* minimum r-divider is 2 */
847 			r = 2;
848 		} else {
849 			/* Take a parent frequency near 400 MHz */
850 			r = (400000000u / rate) & ~1;
851 		}
852 		*parent_rate = r * rate;
853 	} else {
854 		/* We cannot change our parent's rate, report what we can do */
855 		r /= rate;
856 		rate = *parent_rate / (r << 1);
857 	}
858 
859 	return rate;
860 }
861 
862 static int si5341_output_clk_set_rate(struct clk_hw *hw, unsigned long rate,
863 		unsigned long parent_rate)
864 {
865 	struct clk_si5341_output *output = to_clk_si5341_output(hw);
866 	u32 r_div;
867 	int err;
868 	u8 r[3];
869 
870 	if (!rate)
871 		return -EINVAL;
872 
873 	/* Frequency divider is (r_div + 1) * 2 */
874 	r_div = (parent_rate / rate) >> 1;
875 
876 	if (r_div <= 1)
877 		r_div = 0;
878 	else if (r_div >= BIT(24))
879 		r_div = BIT(24) - 1;
880 	else
881 		--r_div;
882 
883 	/* For a value of "2", we set the "OUT0_RDIV_FORCE2" bit */
884 	err = regmap_update_bits(output->data->regmap,
885 			SI5341_OUT_CONFIG(output),
886 			SI5341_OUT_CFG_RDIV_FORCE2,
887 			(r_div == 0) ? SI5341_OUT_CFG_RDIV_FORCE2 : 0);
888 	if (err < 0)
889 		return err;
890 
891 	/* Always write Rx_REG, because a zero value disables the divider */
892 	r[0] = r_div ? (r_div & 0xff) : 1;
893 	r[1] = (r_div >> 8) & 0xff;
894 	r[2] = (r_div >> 16) & 0xff;
895 	err = regmap_bulk_write(output->data->regmap,
896 			SI5341_OUT_R_REG(output), r, 3);
897 
898 	return 0;
899 }
900 
901 static int si5341_output_reparent(struct clk_si5341_output *output, u8 index)
902 {
903 	return regmap_update_bits(output->data->regmap,
904 		SI5341_OUT_MUX_SEL(output), 0x07, index);
905 }
906 
907 static int si5341_output_set_parent(struct clk_hw *hw, u8 index)
908 {
909 	struct clk_si5341_output *output = to_clk_si5341_output(hw);
910 
911 	if (index >= output->data->num_synth)
912 		return -EINVAL;
913 
914 	return si5341_output_reparent(output, index);
915 }
916 
917 static u8 si5341_output_get_parent(struct clk_hw *hw)
918 {
919 	struct clk_si5341_output *output = to_clk_si5341_output(hw);
920 	u32 val;
921 
922 	regmap_read(output->data->regmap, SI5341_OUT_MUX_SEL(output), &val);
923 
924 	return val & 0x7;
925 }
926 
927 static const struct clk_ops si5341_output_clk_ops = {
928 	.is_prepared = si5341_output_clk_is_on,
929 	.prepare = si5341_output_clk_prepare,
930 	.unprepare = si5341_output_clk_unprepare,
931 	.recalc_rate = si5341_output_clk_recalc_rate,
932 	.round_rate = si5341_output_clk_round_rate,
933 	.set_rate = si5341_output_clk_set_rate,
934 	.set_parent = si5341_output_set_parent,
935 	.get_parent = si5341_output_get_parent,
936 };
937 
938 /*
939  * The chip can be bought in a pre-programmed version, or one can program the
940  * NVM in the chip to boot up in a preset mode. This routine tries to determine
941  * if that's the case, or if we need to reset and program everything from
942  * scratch. Returns negative error, or true/false.
943  */
944 static int si5341_is_programmed_already(struct clk_si5341 *data)
945 {
946 	int err;
947 	u8 r[4];
948 
949 	/* Read the PLL divider value, it must have a non-zero value */
950 	err = regmap_bulk_read(data->regmap, SI5341_PLL_M_DEN,
951 			r, ARRAY_SIZE(r));
952 	if (err < 0)
953 		return err;
954 
955 	return !!get_unaligned_le32(r);
956 }
957 
958 static struct clk_hw *
959 of_clk_si5341_get(struct of_phandle_args *clkspec, void *_data)
960 {
961 	struct clk_si5341 *data = _data;
962 	unsigned int idx = clkspec->args[1];
963 	unsigned int group = clkspec->args[0];
964 
965 	switch (group) {
966 	case 0:
967 		if (idx >= data->num_outputs) {
968 			dev_err(&data->i2c_client->dev,
969 				"invalid output index %u\n", idx);
970 			return ERR_PTR(-EINVAL);
971 		}
972 		return &data->clk[idx].hw;
973 	case 1:
974 		if (idx >= data->num_synth) {
975 			dev_err(&data->i2c_client->dev,
976 				"invalid synthesizer index %u\n", idx);
977 			return ERR_PTR(-EINVAL);
978 		}
979 		return &data->synth[idx].hw;
980 	case 2:
981 		if (idx > 0) {
982 			dev_err(&data->i2c_client->dev,
983 				"invalid PLL index %u\n", idx);
984 			return ERR_PTR(-EINVAL);
985 		}
986 		return &data->hw;
987 	default:
988 		dev_err(&data->i2c_client->dev, "invalid group %u\n", group);
989 		return ERR_PTR(-EINVAL);
990 	}
991 }
992 
993 static int si5341_probe_chip_id(struct clk_si5341 *data)
994 {
995 	int err;
996 	u8 reg[4];
997 	u16 model;
998 
999 	err = regmap_bulk_read(data->regmap, SI5341_PN_BASE, reg,
1000 				ARRAY_SIZE(reg));
1001 	if (err < 0) {
1002 		dev_err(&data->i2c_client->dev, "Failed to read chip ID\n");
1003 		return err;
1004 	}
1005 
1006 	model = get_unaligned_le16(reg);
1007 
1008 	dev_info(&data->i2c_client->dev, "Chip: %x Grade: %u Rev: %u\n",
1009 		 model, reg[2], reg[3]);
1010 
1011 	switch (model) {
1012 	case 0x5340:
1013 		data->num_outputs = SI5340_MAX_NUM_OUTPUTS;
1014 		data->num_synth = SI5340_NUM_SYNTH;
1015 		data->reg_output_offset = si5340_reg_output_offset;
1016 		data->reg_rdiv_offset = si5340_reg_rdiv_offset;
1017 		break;
1018 	case 0x5341:
1019 		data->num_outputs = SI5341_MAX_NUM_OUTPUTS;
1020 		data->num_synth = SI5341_NUM_SYNTH;
1021 		data->reg_output_offset = si5341_reg_output_offset;
1022 		data->reg_rdiv_offset = si5341_reg_rdiv_offset;
1023 		break;
1024 	case 0x5342:
1025 		data->num_outputs = SI5342_MAX_NUM_OUTPUTS;
1026 		data->num_synth = SI5342_NUM_SYNTH;
1027 		data->reg_output_offset = si5340_reg_output_offset;
1028 		data->reg_rdiv_offset = si5340_reg_rdiv_offset;
1029 		break;
1030 	case 0x5344:
1031 		data->num_outputs = SI5344_MAX_NUM_OUTPUTS;
1032 		data->num_synth = SI5344_NUM_SYNTH;
1033 		data->reg_output_offset = si5340_reg_output_offset;
1034 		data->reg_rdiv_offset = si5340_reg_rdiv_offset;
1035 		break;
1036 	case 0x5345:
1037 		data->num_outputs = SI5345_MAX_NUM_OUTPUTS;
1038 		data->num_synth = SI5345_NUM_SYNTH;
1039 		data->reg_output_offset = si5341_reg_output_offset;
1040 		data->reg_rdiv_offset = si5341_reg_rdiv_offset;
1041 		break;
1042 	default:
1043 		dev_err(&data->i2c_client->dev, "Model '%x' not supported\n",
1044 			model);
1045 		return -EINVAL;
1046 	}
1047 
1048 	data->chip_id = model;
1049 
1050 	return 0;
1051 }
1052 
1053 /* Read active settings into the regmap cache for later reference */
1054 static int si5341_read_settings(struct clk_si5341 *data)
1055 {
1056 	int err;
1057 	u8 i;
1058 	u8 r[10];
1059 
1060 	err = regmap_bulk_read(data->regmap, SI5341_PLL_M_NUM, r, 10);
1061 	if (err < 0)
1062 		return err;
1063 
1064 	err = regmap_bulk_read(data->regmap,
1065 				SI5341_SYNTH_N_CLK_TO_OUTX_EN, r, 3);
1066 	if (err < 0)
1067 		return err;
1068 
1069 	err = regmap_bulk_read(data->regmap,
1070 				SI5341_SYNTH_N_CLK_DIS, r, 1);
1071 	if (err < 0)
1072 		return err;
1073 
1074 	for (i = 0; i < data->num_synth; ++i) {
1075 		err = regmap_bulk_read(data->regmap,
1076 					SI5341_SYNTH_N_NUM(i), r, 10);
1077 		if (err < 0)
1078 			return err;
1079 	}
1080 
1081 	for (i = 0; i < data->num_outputs; ++i) {
1082 		err = regmap_bulk_read(data->regmap,
1083 					data->reg_output_offset[i], r, 4);
1084 		if (err < 0)
1085 			return err;
1086 
1087 		err = regmap_bulk_read(data->regmap,
1088 					data->reg_rdiv_offset[i], r, 3);
1089 		if (err < 0)
1090 			return err;
1091 	}
1092 
1093 	return 0;
1094 }
1095 
1096 static int si5341_write_multiple(struct clk_si5341 *data,
1097 	const struct si5341_reg_default *values, unsigned int num_values)
1098 {
1099 	unsigned int i;
1100 	int res;
1101 
1102 	for (i = 0; i < num_values; ++i) {
1103 		res = regmap_write(data->regmap,
1104 			values[i].address, values[i].value);
1105 		if (res < 0) {
1106 			dev_err(&data->i2c_client->dev,
1107 				"Failed to write %#x:%#x\n",
1108 				values[i].address, values[i].value);
1109 			return res;
1110 		}
1111 	}
1112 
1113 	return 0;
1114 }
1115 
1116 static const struct si5341_reg_default si5341_preamble[] = {
1117 	{ 0x0B25, 0x00 },
1118 	{ 0x0502, 0x01 },
1119 	{ 0x0505, 0x03 },
1120 	{ 0x0957, 0x17 },
1121 	{ 0x0B4E, 0x1A },
1122 };
1123 
1124 static const struct si5341_reg_default si5345_preamble[] = {
1125 	{ 0x0B25, 0x00 },
1126 	{ 0x0540, 0x01 },
1127 };
1128 
1129 static int si5341_send_preamble(struct clk_si5341 *data)
1130 {
1131 	int res;
1132 	u32 revision;
1133 
1134 	/* For revision 2 and up, the values are slightly different */
1135 	res = regmap_read(data->regmap, SI5341_DEVICE_REV, &revision);
1136 	if (res < 0)
1137 		return res;
1138 
1139 	/* Write "preamble" as specified by datasheet */
1140 	res = regmap_write(data->regmap, 0xB24, revision < 2 ? 0xD8 : 0xC0);
1141 	if (res < 0)
1142 		return res;
1143 
1144 	/* The si5342..si5345 require a different preamble */
1145 	if (data->chip_id > 0x5341)
1146 		res = si5341_write_multiple(data,
1147 			si5345_preamble, ARRAY_SIZE(si5345_preamble));
1148 	else
1149 		res = si5341_write_multiple(data,
1150 			si5341_preamble, ARRAY_SIZE(si5341_preamble));
1151 	if (res < 0)
1152 		return res;
1153 
1154 	/* Datasheet specifies a 300ms wait after sending the preamble */
1155 	msleep(300);
1156 
1157 	return 0;
1158 }
1159 
1160 /* Perform a soft reset and write post-amble */
1161 static int si5341_finalize_defaults(struct clk_si5341 *data)
1162 {
1163 	int res;
1164 	u32 revision;
1165 
1166 	res = regmap_write(data->regmap, SI5341_IO_VDD_SEL,
1167 			   data->iovdd_33 ? 1 : 0);
1168 	if (res < 0)
1169 		return res;
1170 
1171 	res = regmap_read(data->regmap, SI5341_DEVICE_REV, &revision);
1172 	if (res < 0)
1173 		return res;
1174 
1175 	dev_dbg(&data->i2c_client->dev, "%s rev=%u\n", __func__, revision);
1176 
1177 	res = regmap_write(data->regmap, SI5341_SOFT_RST, 0x01);
1178 	if (res < 0)
1179 		return res;
1180 
1181 	/* The si5342..si5345 have an additional post-amble */
1182 	if (data->chip_id > 0x5341) {
1183 		res = regmap_write(data->regmap, 0x540, 0x0);
1184 		if (res < 0)
1185 			return res;
1186 	}
1187 
1188 	/* Datasheet does not explain these nameless registers */
1189 	res = regmap_write(data->regmap, 0xB24, revision < 2 ? 0xDB : 0xC3);
1190 	if (res < 0)
1191 		return res;
1192 	res = regmap_write(data->regmap, 0x0B25, 0x02);
1193 	if (res < 0)
1194 		return res;
1195 
1196 	return 0;
1197 }
1198 
1199 
1200 static const struct regmap_range si5341_regmap_volatile_range[] = {
1201 	regmap_reg_range(0x000C, 0x0012), /* Status */
1202 	regmap_reg_range(0x001C, 0x001E), /* reset, finc/fdec */
1203 	regmap_reg_range(0x00E2, 0x00FE), /* NVM, interrupts, device ready */
1204 	/* Update bits for P divider and synth config */
1205 	regmap_reg_range(SI5341_PX_UPD, SI5341_PX_UPD),
1206 	regmap_reg_range(SI5341_SYNTH_N_UPD(0), SI5341_SYNTH_N_UPD(0)),
1207 	regmap_reg_range(SI5341_SYNTH_N_UPD(1), SI5341_SYNTH_N_UPD(1)),
1208 	regmap_reg_range(SI5341_SYNTH_N_UPD(2), SI5341_SYNTH_N_UPD(2)),
1209 	regmap_reg_range(SI5341_SYNTH_N_UPD(3), SI5341_SYNTH_N_UPD(3)),
1210 	regmap_reg_range(SI5341_SYNTH_N_UPD(4), SI5341_SYNTH_N_UPD(4)),
1211 };
1212 
1213 static const struct regmap_access_table si5341_regmap_volatile = {
1214 	.yes_ranges = si5341_regmap_volatile_range,
1215 	.n_yes_ranges = ARRAY_SIZE(si5341_regmap_volatile_range),
1216 };
1217 
1218 /* Pages 0, 1, 2, 3, 9, A, B are valid, so there are 12 pages */
1219 static const struct regmap_range_cfg si5341_regmap_ranges[] = {
1220 	{
1221 		.range_min = 0,
1222 		.range_max = SI5341_REGISTER_MAX,
1223 		.selector_reg = SI5341_PAGE,
1224 		.selector_mask = 0xff,
1225 		.selector_shift = 0,
1226 		.window_start = 0,
1227 		.window_len = 256,
1228 	},
1229 };
1230 
1231 static int si5341_wait_device_ready(struct i2c_client *client)
1232 {
1233 	int count;
1234 
1235 	/* Datasheet warns: Any attempt to read or write any register other
1236 	 * than DEVICE_READY before DEVICE_READY reads as 0x0F may corrupt the
1237 	 * NVM programming and may corrupt the register contents, as they are
1238 	 * read from NVM. Note that this includes accesses to the PAGE register.
1239 	 * Also: DEVICE_READY is available on every register page, so no page
1240 	 * change is needed to read it.
1241 	 * Do this outside regmap to avoid automatic PAGE register access.
1242 	 * May take up to 300ms to complete.
1243 	 */
1244 	for (count = 0; count < 15; ++count) {
1245 		s32 result = i2c_smbus_read_byte_data(client,
1246 						      SI5341_DEVICE_READY);
1247 		if (result < 0)
1248 			return result;
1249 		if (result == 0x0F)
1250 			return 0;
1251 		msleep(20);
1252 	}
1253 	dev_err(&client->dev, "timeout waiting for DEVICE_READY\n");
1254 	return -EIO;
1255 }
1256 
1257 static const struct regmap_config si5341_regmap_config = {
1258 	.reg_bits = 8,
1259 	.val_bits = 8,
1260 	.cache_type = REGCACHE_RBTREE,
1261 	.ranges = si5341_regmap_ranges,
1262 	.num_ranges = ARRAY_SIZE(si5341_regmap_ranges),
1263 	.max_register = SI5341_REGISTER_MAX,
1264 	.volatile_table = &si5341_regmap_volatile,
1265 };
1266 
1267 static int si5341_dt_parse_dt(struct clk_si5341 *data,
1268 			      struct clk_si5341_output_config *config)
1269 {
1270 	struct device_node *child;
1271 	struct device_node *np = data->i2c_client->dev.of_node;
1272 	u32 num;
1273 	u32 val;
1274 
1275 	memset(config, 0, sizeof(struct clk_si5341_output_config) *
1276 				SI5341_MAX_NUM_OUTPUTS);
1277 
1278 	for_each_child_of_node(np, child) {
1279 		if (of_property_read_u32(child, "reg", &num)) {
1280 			dev_err(&data->i2c_client->dev, "missing reg property of %s\n",
1281 				child->name);
1282 			goto put_child;
1283 		}
1284 
1285 		if (num >= SI5341_MAX_NUM_OUTPUTS) {
1286 			dev_err(&data->i2c_client->dev, "invalid clkout %d\n", num);
1287 			goto put_child;
1288 		}
1289 
1290 		if (!of_property_read_u32(child, "silabs,format", &val)) {
1291 			/* Set cm and ampl conservatively to 3v3 settings */
1292 			switch (val) {
1293 			case 1: /* normal differential */
1294 				config[num].out_cm_ampl_bits = 0x33;
1295 				break;
1296 			case 2: /* low-power differential */
1297 				config[num].out_cm_ampl_bits = 0x13;
1298 				break;
1299 			case 4: /* LVCMOS */
1300 				config[num].out_cm_ampl_bits = 0x33;
1301 				/* Set SI recommended impedance for LVCMOS */
1302 				config[num].out_format_drv_bits |= 0xc0;
1303 				break;
1304 			default:
1305 				dev_err(&data->i2c_client->dev,
1306 					"invalid silabs,format %u for %u\n",
1307 					val, num);
1308 				goto put_child;
1309 			}
1310 			config[num].out_format_drv_bits &= ~0x07;
1311 			config[num].out_format_drv_bits |= val & 0x07;
1312 			/* Always enable the SYNC feature */
1313 			config[num].out_format_drv_bits |= 0x08;
1314 		}
1315 
1316 		if (!of_property_read_u32(child, "silabs,common-mode", &val)) {
1317 			if (val > 0xf) {
1318 				dev_err(&data->i2c_client->dev,
1319 					"invalid silabs,common-mode %u\n",
1320 					val);
1321 				goto put_child;
1322 			}
1323 			config[num].out_cm_ampl_bits &= 0xf0;
1324 			config[num].out_cm_ampl_bits |= val & 0x0f;
1325 		}
1326 
1327 		if (!of_property_read_u32(child, "silabs,amplitude", &val)) {
1328 			if (val > 0xf) {
1329 				dev_err(&data->i2c_client->dev,
1330 					"invalid silabs,amplitude %u\n",
1331 					val);
1332 				goto put_child;
1333 			}
1334 			config[num].out_cm_ampl_bits &= 0x0f;
1335 			config[num].out_cm_ampl_bits |= (val << 4) & 0xf0;
1336 		}
1337 
1338 		if (of_property_read_bool(child, "silabs,disable-high"))
1339 			config[num].out_format_drv_bits |= 0x10;
1340 
1341 		config[num].synth_master =
1342 			of_property_read_bool(child, "silabs,synth-master");
1343 
1344 		config[num].always_on =
1345 			of_property_read_bool(child, "always-on");
1346 
1347 		config[num].vdd_sel_bits = 0x08;
1348 		if (data->clk[num].vddo_reg) {
1349 			int vdd = regulator_get_voltage(data->clk[num].vddo_reg);
1350 
1351 			switch (vdd) {
1352 			case 3300000:
1353 				config[num].vdd_sel_bits |= 0 << 4;
1354 				break;
1355 			case 1800000:
1356 				config[num].vdd_sel_bits |= 1 << 4;
1357 				break;
1358 			case 2500000:
1359 				config[num].vdd_sel_bits |= 2 << 4;
1360 				break;
1361 			default:
1362 				dev_err(&data->i2c_client->dev,
1363 					"unsupported vddo voltage %d for %s\n",
1364 					vdd, child->name);
1365 				goto put_child;
1366 			}
1367 		} else {
1368 			/* chip seems to default to 2.5V when not set */
1369 			dev_warn(&data->i2c_client->dev,
1370 				"no regulator set, defaulting vdd_sel to 2.5V for %s\n",
1371 				child->name);
1372 			config[num].vdd_sel_bits |= 2 << 4;
1373 		}
1374 	}
1375 
1376 	return 0;
1377 
1378 put_child:
1379 	of_node_put(child);
1380 	return -EINVAL;
1381 }
1382 
1383 /*
1384  * If not pre-configured, calculate and set the PLL configuration manually.
1385  * For low-jitter performance, the PLL should be set such that the synthesizers
1386  * only need integer division.
1387  * Without any user guidance, we'll set the PLL to 14GHz, which still allows
1388  * the chip to generate any frequency on its outputs, but jitter performance
1389  * may be sub-optimal.
1390  */
1391 static int si5341_initialize_pll(struct clk_si5341 *data)
1392 {
1393 	struct device_node *np = data->i2c_client->dev.of_node;
1394 	u32 m_num = 0;
1395 	u32 m_den = 0;
1396 	int sel;
1397 
1398 	if (of_property_read_u32(np, "silabs,pll-m-num", &m_num)) {
1399 		dev_err(&data->i2c_client->dev,
1400 			"PLL configuration requires silabs,pll-m-num\n");
1401 	}
1402 	if (of_property_read_u32(np, "silabs,pll-m-den", &m_den)) {
1403 		dev_err(&data->i2c_client->dev,
1404 			"PLL configuration requires silabs,pll-m-den\n");
1405 	}
1406 
1407 	if (!m_num || !m_den) {
1408 		dev_err(&data->i2c_client->dev,
1409 			"PLL configuration invalid, assume 14GHz\n");
1410 		sel = si5341_clk_get_selected_input(data);
1411 		if (sel < 0)
1412 			return sel;
1413 
1414 		m_den = clk_get_rate(data->input_clk[sel]) / 10;
1415 		m_num = 1400000000;
1416 	}
1417 
1418 	return si5341_encode_44_32(data->regmap,
1419 			SI5341_PLL_M_NUM, m_num, m_den);
1420 }
1421 
1422 static int si5341_clk_select_active_input(struct clk_si5341 *data)
1423 {
1424 	int res;
1425 	int err;
1426 	int i;
1427 
1428 	res = si5341_clk_get_selected_input(data);
1429 	if (res < 0)
1430 		return res;
1431 
1432 	/* If the current register setting is invalid, pick the first input */
1433 	if (!data->input_clk[res]) {
1434 		dev_dbg(&data->i2c_client->dev,
1435 			"Input %d not connected, rerouting\n", res);
1436 		res = -ENODEV;
1437 		for (i = 0; i < SI5341_NUM_INPUTS; ++i) {
1438 			if (data->input_clk[i]) {
1439 				res = i;
1440 				break;
1441 			}
1442 		}
1443 		if (res < 0) {
1444 			dev_err(&data->i2c_client->dev,
1445 				"No clock input available\n");
1446 			return res;
1447 		}
1448 	}
1449 
1450 	/* Make sure the selected clock is also enabled and routed */
1451 	err = si5341_clk_reparent(data, res);
1452 	if (err < 0)
1453 		return err;
1454 
1455 	err = clk_prepare_enable(data->input_clk[res]);
1456 	if (err < 0)
1457 		return err;
1458 
1459 	return res;
1460 }
1461 
1462 static ssize_t input_present_show(struct device *dev,
1463 				  struct device_attribute *attr,
1464 				  char *buf)
1465 {
1466 	struct clk_si5341 *data = dev_get_drvdata(dev);
1467 	u32 status;
1468 	int res = regmap_read(data->regmap, SI5341_STATUS, &status);
1469 
1470 	if (res < 0)
1471 		return res;
1472 	res = !(status & SI5341_STATUS_LOSREF);
1473 	return sysfs_emit(buf, "%d\n", res);
1474 }
1475 static DEVICE_ATTR_RO(input_present);
1476 
1477 static ssize_t input_present_sticky_show(struct device *dev,
1478 					 struct device_attribute *attr,
1479 					 char *buf)
1480 {
1481 	struct clk_si5341 *data = dev_get_drvdata(dev);
1482 	u32 status;
1483 	int res = regmap_read(data->regmap, SI5341_STATUS_STICKY, &status);
1484 
1485 	if (res < 0)
1486 		return res;
1487 	res = !(status & SI5341_STATUS_LOSREF);
1488 	return sysfs_emit(buf, "%d\n", res);
1489 }
1490 static DEVICE_ATTR_RO(input_present_sticky);
1491 
1492 static ssize_t pll_locked_show(struct device *dev,
1493 			       struct device_attribute *attr,
1494 			       char *buf)
1495 {
1496 	struct clk_si5341 *data = dev_get_drvdata(dev);
1497 	u32 status;
1498 	int res = regmap_read(data->regmap, SI5341_STATUS, &status);
1499 
1500 	if (res < 0)
1501 		return res;
1502 	res = !(status & SI5341_STATUS_LOL);
1503 	return sysfs_emit(buf, "%d\n", res);
1504 }
1505 static DEVICE_ATTR_RO(pll_locked);
1506 
1507 static ssize_t pll_locked_sticky_show(struct device *dev,
1508 				      struct device_attribute *attr,
1509 				      char *buf)
1510 {
1511 	struct clk_si5341 *data = dev_get_drvdata(dev);
1512 	u32 status;
1513 	int res = regmap_read(data->regmap, SI5341_STATUS_STICKY, &status);
1514 
1515 	if (res < 0)
1516 		return res;
1517 	res = !(status & SI5341_STATUS_LOL);
1518 	return sysfs_emit(buf, "%d\n", res);
1519 }
1520 static DEVICE_ATTR_RO(pll_locked_sticky);
1521 
1522 static ssize_t clear_sticky_store(struct device *dev,
1523 				  struct device_attribute *attr,
1524 				  const char *buf, size_t count)
1525 {
1526 	struct clk_si5341 *data = dev_get_drvdata(dev);
1527 	long val;
1528 
1529 	if (kstrtol(buf, 10, &val))
1530 		return -EINVAL;
1531 	if (val) {
1532 		int res = regmap_write(data->regmap, SI5341_STATUS_STICKY, 0);
1533 
1534 		if (res < 0)
1535 			return res;
1536 	}
1537 	return count;
1538 }
1539 static DEVICE_ATTR_WO(clear_sticky);
1540 
1541 static const struct attribute *si5341_attributes[] = {
1542 	&dev_attr_input_present.attr,
1543 	&dev_attr_input_present_sticky.attr,
1544 	&dev_attr_pll_locked.attr,
1545 	&dev_attr_pll_locked_sticky.attr,
1546 	&dev_attr_clear_sticky.attr,
1547 	NULL
1548 };
1549 
1550 static int si5341_probe(struct i2c_client *client,
1551 		const struct i2c_device_id *id)
1552 {
1553 	struct clk_si5341 *data;
1554 	struct clk_init_data init;
1555 	struct clk *input;
1556 	const char *root_clock_name;
1557 	const char *synth_clock_names[SI5341_NUM_SYNTH];
1558 	int err;
1559 	unsigned int i;
1560 	struct clk_si5341_output_config config[SI5341_MAX_NUM_OUTPUTS];
1561 	bool initialization_required;
1562 	u32 status;
1563 
1564 	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
1565 	if (!data)
1566 		return -ENOMEM;
1567 
1568 	data->i2c_client = client;
1569 
1570 	/* Must be done before otherwise touching hardware */
1571 	err = si5341_wait_device_ready(client);
1572 	if (err)
1573 		return err;
1574 
1575 	for (i = 0; i < SI5341_NUM_INPUTS; ++i) {
1576 		input = devm_clk_get(&client->dev, si5341_input_clock_names[i]);
1577 		if (IS_ERR(input)) {
1578 			if (PTR_ERR(input) == -EPROBE_DEFER)
1579 				return -EPROBE_DEFER;
1580 			data->input_clk_name[i] = si5341_input_clock_names[i];
1581 		} else {
1582 			data->input_clk[i] = input;
1583 			data->input_clk_name[i] = __clk_get_name(input);
1584 		}
1585 	}
1586 
1587 	for (i = 0; i < SI5341_MAX_NUM_OUTPUTS; ++i) {
1588 		char reg_name[10];
1589 
1590 		snprintf(reg_name, sizeof(reg_name), "vddo%d", i);
1591 		data->clk[i].vddo_reg = devm_regulator_get_optional(
1592 			&client->dev, reg_name);
1593 		if (IS_ERR(data->clk[i].vddo_reg)) {
1594 			err = PTR_ERR(data->clk[i].vddo_reg);
1595 			data->clk[i].vddo_reg = NULL;
1596 			if (err == -ENODEV)
1597 				continue;
1598 			goto cleanup;
1599 		} else {
1600 			err = regulator_enable(data->clk[i].vddo_reg);
1601 			if (err) {
1602 				dev_err(&client->dev,
1603 					"failed to enable %s regulator: %d\n",
1604 					reg_name, err);
1605 				data->clk[i].vddo_reg = NULL;
1606 				goto cleanup;
1607 			}
1608 		}
1609 	}
1610 
1611 	err = si5341_dt_parse_dt(data, config);
1612 	if (err)
1613 		goto cleanup;
1614 
1615 	if (of_property_read_string(client->dev.of_node, "clock-output-names",
1616 			&init.name))
1617 		init.name = client->dev.of_node->name;
1618 	root_clock_name = init.name;
1619 
1620 	data->regmap = devm_regmap_init_i2c(client, &si5341_regmap_config);
1621 	if (IS_ERR(data->regmap)) {
1622 		err = PTR_ERR(data->regmap);
1623 		goto cleanup;
1624 	}
1625 
1626 	i2c_set_clientdata(client, data);
1627 
1628 	err = si5341_probe_chip_id(data);
1629 	if (err < 0)
1630 		goto cleanup;
1631 
1632 	if (of_property_read_bool(client->dev.of_node, "silabs,reprogram")) {
1633 		initialization_required = true;
1634 	} else {
1635 		err = si5341_is_programmed_already(data);
1636 		if (err < 0)
1637 			goto cleanup;
1638 
1639 		initialization_required = !err;
1640 	}
1641 	data->xaxb_ext_clk = of_property_read_bool(client->dev.of_node,
1642 						   "silabs,xaxb-ext-clk");
1643 	data->iovdd_33 = of_property_read_bool(client->dev.of_node,
1644 					       "silabs,iovdd-33");
1645 
1646 	if (initialization_required) {
1647 		/* Populate the regmap cache in preparation for "cache only" */
1648 		err = si5341_read_settings(data);
1649 		if (err < 0)
1650 			goto cleanup;
1651 
1652 		err = si5341_send_preamble(data);
1653 		if (err < 0)
1654 			goto cleanup;
1655 
1656 		/*
1657 		 * We intend to send all 'final' register values in a single
1658 		 * transaction. So cache all register writes until we're done
1659 		 * configuring.
1660 		 */
1661 		regcache_cache_only(data->regmap, true);
1662 
1663 		/* Write the configuration pairs from the firmware blob */
1664 		err = si5341_write_multiple(data, si5341_reg_defaults,
1665 					ARRAY_SIZE(si5341_reg_defaults));
1666 		if (err < 0)
1667 			goto cleanup;
1668 	}
1669 
1670 	/* Input must be up and running at this point */
1671 	err = si5341_clk_select_active_input(data);
1672 	if (err < 0)
1673 		goto cleanup;
1674 
1675 	if (initialization_required) {
1676 		/* PLL configuration is required */
1677 		err = si5341_initialize_pll(data);
1678 		if (err < 0)
1679 			goto cleanup;
1680 	}
1681 
1682 	/* Register the PLL */
1683 	init.parent_names = data->input_clk_name;
1684 	init.num_parents = SI5341_NUM_INPUTS;
1685 	init.ops = &si5341_clk_ops;
1686 	init.flags = 0;
1687 	data->hw.init = &init;
1688 
1689 	err = devm_clk_hw_register(&client->dev, &data->hw);
1690 	if (err) {
1691 		dev_err(&client->dev, "clock registration failed\n");
1692 		goto cleanup;
1693 	}
1694 
1695 	init.num_parents = 1;
1696 	init.parent_names = &root_clock_name;
1697 	init.ops = &si5341_synth_clk_ops;
1698 	for (i = 0; i < data->num_synth; ++i) {
1699 		synth_clock_names[i] = devm_kasprintf(&client->dev, GFP_KERNEL,
1700 				"%s.N%u", client->dev.of_node->name, i);
1701 		init.name = synth_clock_names[i];
1702 		data->synth[i].index = i;
1703 		data->synth[i].data = data;
1704 		data->synth[i].hw.init = &init;
1705 		err = devm_clk_hw_register(&client->dev, &data->synth[i].hw);
1706 		if (err) {
1707 			dev_err(&client->dev,
1708 				"synth N%u registration failed\n", i);
1709 		}
1710 	}
1711 
1712 	init.num_parents = data->num_synth;
1713 	init.parent_names = synth_clock_names;
1714 	init.ops = &si5341_output_clk_ops;
1715 	for (i = 0; i < data->num_outputs; ++i) {
1716 		init.name = kasprintf(GFP_KERNEL, "%s.%d",
1717 			client->dev.of_node->name, i);
1718 		init.flags = config[i].synth_master ? CLK_SET_RATE_PARENT : 0;
1719 		data->clk[i].index = i;
1720 		data->clk[i].data = data;
1721 		data->clk[i].hw.init = &init;
1722 		if (config[i].out_format_drv_bits & 0x07) {
1723 			regmap_write(data->regmap,
1724 				SI5341_OUT_FORMAT(&data->clk[i]),
1725 				config[i].out_format_drv_bits);
1726 			regmap_write(data->regmap,
1727 				SI5341_OUT_CM(&data->clk[i]),
1728 				config[i].out_cm_ampl_bits);
1729 			regmap_update_bits(data->regmap,
1730 				SI5341_OUT_MUX_SEL(&data->clk[i]),
1731 				SI5341_OUT_MUX_VDD_SEL_MASK,
1732 				config[i].vdd_sel_bits);
1733 		}
1734 		err = devm_clk_hw_register(&client->dev, &data->clk[i].hw);
1735 		kfree(init.name); /* clock framework made a copy of the name */
1736 		if (err) {
1737 			dev_err(&client->dev,
1738 				"output %u registration failed\n", i);
1739 			goto cleanup;
1740 		}
1741 		if (config[i].always_on)
1742 			clk_prepare(data->clk[i].hw.clk);
1743 	}
1744 
1745 	err = devm_of_clk_add_hw_provider(&client->dev, of_clk_si5341_get,
1746 			data);
1747 	if (err) {
1748 		dev_err(&client->dev, "unable to add clk provider\n");
1749 		goto cleanup;
1750 	}
1751 
1752 	if (initialization_required) {
1753 		/* Synchronize */
1754 		regcache_cache_only(data->regmap, false);
1755 		err = regcache_sync(data->regmap);
1756 		if (err < 0)
1757 			goto cleanup;
1758 
1759 		err = si5341_finalize_defaults(data);
1760 		if (err < 0)
1761 			goto cleanup;
1762 	}
1763 
1764 	/* wait for device to report input clock present and PLL lock */
1765 	err = regmap_read_poll_timeout(data->regmap, SI5341_STATUS, status,
1766 		!(status & (SI5341_STATUS_LOSREF | SI5341_STATUS_LOL)),
1767 	       10000, 250000);
1768 	if (err) {
1769 		dev_err(&client->dev, "Error waiting for input clock or PLL lock\n");
1770 		goto cleanup;
1771 	}
1772 
1773 	/* clear sticky alarm bits from initialization */
1774 	err = regmap_write(data->regmap, SI5341_STATUS_STICKY, 0);
1775 	if (err) {
1776 		dev_err(&client->dev, "unable to clear sticky status\n");
1777 		goto cleanup;
1778 	}
1779 
1780 	err = sysfs_create_files(&client->dev.kobj, si5341_attributes);
1781 	if (err) {
1782 		dev_err(&client->dev, "unable to create sysfs files\n");
1783 		goto cleanup;
1784 	}
1785 
1786 	/* Free the names, clk framework makes copies */
1787 	for (i = 0; i < data->num_synth; ++i)
1788 		 devm_kfree(&client->dev, (void *)synth_clock_names[i]);
1789 
1790 	return 0;
1791 
1792 cleanup:
1793 	for (i = 0; i < SI5341_MAX_NUM_OUTPUTS; ++i) {
1794 		if (data->clk[i].vddo_reg)
1795 			regulator_disable(data->clk[i].vddo_reg);
1796 	}
1797 	return err;
1798 }
1799 
1800 static int si5341_remove(struct i2c_client *client)
1801 {
1802 	struct clk_si5341 *data = i2c_get_clientdata(client);
1803 	int i;
1804 
1805 	sysfs_remove_files(&client->dev.kobj, si5341_attributes);
1806 
1807 	for (i = 0; i < SI5341_MAX_NUM_OUTPUTS; ++i) {
1808 		if (data->clk[i].vddo_reg)
1809 			regulator_disable(data->clk[i].vddo_reg);
1810 	}
1811 
1812 	return 0;
1813 }
1814 
1815 static const struct i2c_device_id si5341_id[] = {
1816 	{ "si5340", 0 },
1817 	{ "si5341", 1 },
1818 	{ "si5342", 2 },
1819 	{ "si5344", 4 },
1820 	{ "si5345", 5 },
1821 	{ }
1822 };
1823 MODULE_DEVICE_TABLE(i2c, si5341_id);
1824 
1825 static const struct of_device_id clk_si5341_of_match[] = {
1826 	{ .compatible = "silabs,si5340" },
1827 	{ .compatible = "silabs,si5341" },
1828 	{ .compatible = "silabs,si5342" },
1829 	{ .compatible = "silabs,si5344" },
1830 	{ .compatible = "silabs,si5345" },
1831 	{ }
1832 };
1833 MODULE_DEVICE_TABLE(of, clk_si5341_of_match);
1834 
1835 static struct i2c_driver si5341_driver = {
1836 	.driver = {
1837 		.name = "si5341",
1838 		.of_match_table = clk_si5341_of_match,
1839 	},
1840 	.probe		= si5341_probe,
1841 	.remove		= si5341_remove,
1842 	.id_table	= si5341_id,
1843 };
1844 module_i2c_driver(si5341_driver);
1845 
1846 MODULE_AUTHOR("Mike Looijmans <mike.looijmans@topic.nl>");
1847 MODULE_DESCRIPTION("Si5341 driver");
1848 MODULE_LICENSE("GPL");
1849