xref: /openbmc/linux/drivers/clk/clk-si5341.c (revision 185c8f33)
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 	.determine_rate = clk_hw_determine_rate_no_reparent,
555 	.set_parent = si5341_clk_set_parent,
556 	.get_parent = si5341_clk_get_parent,
557 	.recalc_rate = si5341_clk_recalc_rate,
558 };
559 
560 /* Synthesizers, there are 5 synthesizers that connect to any of the outputs */
561 
562 /* The synthesizer is on if all power and enable bits are set */
563 static int si5341_synth_clk_is_on(struct clk_hw *hw)
564 {
565 	struct clk_si5341_synth *synth = to_clk_si5341_synth(hw);
566 	int err;
567 	u32 val;
568 	u8 index = synth->index;
569 
570 	err = regmap_read(synth->data->regmap,
571 			SI5341_SYNTH_N_CLK_TO_OUTX_EN, &val);
572 	if (err < 0)
573 		return 0;
574 
575 	if (!(val & BIT(index)))
576 		return 0;
577 
578 	err = regmap_read(synth->data->regmap, SI5341_SYNTH_N_PDNB, &val);
579 	if (err < 0)
580 		return 0;
581 
582 	if (!(val & BIT(index)))
583 		return 0;
584 
585 	/* This bit must be 0 for the synthesizer to receive clock input */
586 	err = regmap_read(synth->data->regmap, SI5341_SYNTH_N_CLK_DIS, &val);
587 	if (err < 0)
588 		return 0;
589 
590 	return !(val & BIT(index));
591 }
592 
593 static void si5341_synth_clk_unprepare(struct clk_hw *hw)
594 {
595 	struct clk_si5341_synth *synth = to_clk_si5341_synth(hw);
596 	u8 index = synth->index; /* In range 0..5 */
597 	u8 mask = BIT(index);
598 
599 	/* Disable output */
600 	regmap_update_bits(synth->data->regmap,
601 		SI5341_SYNTH_N_CLK_TO_OUTX_EN, mask, 0);
602 	/* Power down */
603 	regmap_update_bits(synth->data->regmap,
604 		SI5341_SYNTH_N_PDNB, mask, 0);
605 	/* Disable clock input to synth (set to 1 to disable) */
606 	regmap_update_bits(synth->data->regmap,
607 		SI5341_SYNTH_N_CLK_DIS, mask, mask);
608 }
609 
610 static int si5341_synth_clk_prepare(struct clk_hw *hw)
611 {
612 	struct clk_si5341_synth *synth = to_clk_si5341_synth(hw);
613 	int err;
614 	u8 index = synth->index;
615 	u8 mask = BIT(index);
616 
617 	/* Power up */
618 	err = regmap_update_bits(synth->data->regmap,
619 		SI5341_SYNTH_N_PDNB, mask, mask);
620 	if (err < 0)
621 		return err;
622 
623 	/* Enable clock input to synth (set bit to 0 to enable) */
624 	err = regmap_update_bits(synth->data->regmap,
625 		SI5341_SYNTH_N_CLK_DIS, mask, 0);
626 	if (err < 0)
627 		return err;
628 
629 	/* Enable output */
630 	return regmap_update_bits(synth->data->regmap,
631 		SI5341_SYNTH_N_CLK_TO_OUTX_EN, mask, mask);
632 }
633 
634 /* Synth clock frequency: Fvco * n_den / n_den, with Fvco in 13500-14256 MHz */
635 static unsigned long si5341_synth_clk_recalc_rate(struct clk_hw *hw,
636 		unsigned long parent_rate)
637 {
638 	struct clk_si5341_synth *synth = to_clk_si5341_synth(hw);
639 	u64 f;
640 	u64 n_num;
641 	u32 n_den;
642 	int err;
643 
644 	err = si5341_decode_44_32(synth->data->regmap,
645 			SI5341_SYNTH_N_NUM(synth->index), &n_num, &n_den);
646 	if (err < 0)
647 		return err;
648 	/* Check for bogus/uninitialized settings */
649 	if (!n_num || !n_den)
650 		return 0;
651 
652 	/*
653 	 * n_num and n_den are shifted left as much as possible, so to prevent
654 	 * overflow in 64-bit math, we shift n_den 4 bits to the right
655 	 */
656 	f = synth->data->freq_vco;
657 	f *= n_den >> 4;
658 
659 	/* Now we need to do 64-bit division: f/n_num */
660 	/* And compensate for the 4 bits we dropped */
661 	f = div64_u64(f, (n_num >> 4));
662 
663 	return f;
664 }
665 
666 static long si5341_synth_clk_round_rate(struct clk_hw *hw, unsigned long rate,
667 		unsigned long *parent_rate)
668 {
669 	struct clk_si5341_synth *synth = to_clk_si5341_synth(hw);
670 	u64 f;
671 
672 	/* The synthesizer accuracy is such that anything in range will work */
673 	f = synth->data->freq_vco;
674 	do_div(f, SI5341_SYNTH_N_MAX);
675 	if (rate < f)
676 		return f;
677 
678 	f = synth->data->freq_vco;
679 	do_div(f, SI5341_SYNTH_N_MIN);
680 	if (rate > f)
681 		return f;
682 
683 	return rate;
684 }
685 
686 static int si5341_synth_program(struct clk_si5341_synth *synth,
687 	u64 n_num, u32 n_den, bool is_integer)
688 {
689 	int err;
690 	u8 index = synth->index;
691 
692 	err = si5341_encode_44_32(synth->data->regmap,
693 			SI5341_SYNTH_N_NUM(index), n_num, n_den);
694 
695 	err = regmap_update_bits(synth->data->regmap,
696 		SI5341_SYNTH_N_PIBYP, BIT(index), is_integer ? BIT(index) : 0);
697 	if (err < 0)
698 		return err;
699 
700 	return regmap_write(synth->data->regmap,
701 		SI5341_SYNTH_N_UPD(index), 0x01);
702 }
703 
704 
705 static int si5341_synth_clk_set_rate(struct clk_hw *hw, unsigned long rate,
706 		unsigned long parent_rate)
707 {
708 	struct clk_si5341_synth *synth = to_clk_si5341_synth(hw);
709 	u64 n_num;
710 	u32 n_den;
711 	u32 r;
712 	u32 g;
713 	bool is_integer;
714 
715 	n_num = synth->data->freq_vco;
716 
717 	/* see if there's an integer solution */
718 	r = do_div(n_num, rate);
719 	is_integer = (r == 0);
720 	if (is_integer) {
721 		/* Integer divider equal to n_num */
722 		n_den = 1;
723 	} else {
724 		/* Calculate a fractional solution */
725 		g = gcd(r, rate);
726 		n_den = rate / g;
727 		n_num *= n_den;
728 		n_num += r / g;
729 	}
730 
731 	dev_dbg(&synth->data->i2c_client->dev,
732 			"%s(%u): n=0x%llx d=0x%x %s\n", __func__,
733 				synth->index, n_num, n_den,
734 				is_integer ? "int" : "frac");
735 
736 	return si5341_synth_program(synth, n_num, n_den, is_integer);
737 }
738 
739 static const struct clk_ops si5341_synth_clk_ops = {
740 	.is_prepared = si5341_synth_clk_is_on,
741 	.prepare = si5341_synth_clk_prepare,
742 	.unprepare = si5341_synth_clk_unprepare,
743 	.recalc_rate = si5341_synth_clk_recalc_rate,
744 	.round_rate = si5341_synth_clk_round_rate,
745 	.set_rate = si5341_synth_clk_set_rate,
746 };
747 
748 static int si5341_output_clk_is_on(struct clk_hw *hw)
749 {
750 	struct clk_si5341_output *output = to_clk_si5341_output(hw);
751 	int err;
752 	u32 val;
753 
754 	err = regmap_read(output->data->regmap,
755 			SI5341_OUT_CONFIG(output), &val);
756 	if (err < 0)
757 		return err;
758 
759 	/* Bit 0=PDN, 1=OE so only a value of 0x2 enables the output */
760 	return (val & 0x03) == SI5341_OUT_CFG_OE;
761 }
762 
763 /* Disables and then powers down the output */
764 static void si5341_output_clk_unprepare(struct clk_hw *hw)
765 {
766 	struct clk_si5341_output *output = to_clk_si5341_output(hw);
767 
768 	regmap_update_bits(output->data->regmap,
769 			SI5341_OUT_CONFIG(output),
770 			SI5341_OUT_CFG_OE, 0);
771 	regmap_update_bits(output->data->regmap,
772 			SI5341_OUT_CONFIG(output),
773 			SI5341_OUT_CFG_PDN, SI5341_OUT_CFG_PDN);
774 }
775 
776 /* Powers up and then enables the output */
777 static int si5341_output_clk_prepare(struct clk_hw *hw)
778 {
779 	struct clk_si5341_output *output = to_clk_si5341_output(hw);
780 	int err;
781 
782 	err = regmap_update_bits(output->data->regmap,
783 			SI5341_OUT_CONFIG(output),
784 			SI5341_OUT_CFG_PDN, 0);
785 	if (err < 0)
786 		return err;
787 
788 	return regmap_update_bits(output->data->regmap,
789 			SI5341_OUT_CONFIG(output),
790 			SI5341_OUT_CFG_OE, SI5341_OUT_CFG_OE);
791 }
792 
793 static unsigned long si5341_output_clk_recalc_rate(struct clk_hw *hw,
794 		unsigned long parent_rate)
795 {
796 	struct clk_si5341_output *output = to_clk_si5341_output(hw);
797 	int err;
798 	u32 val;
799 	u32 r_divider;
800 	u8 r[3];
801 
802 	err = regmap_read(output->data->regmap,
803 			SI5341_OUT_CONFIG(output), &val);
804 	if (err < 0)
805 		return err;
806 
807 	/* If SI5341_OUT_CFG_RDIV_FORCE2 is set, r_divider is 2 */
808 	if (val & SI5341_OUT_CFG_RDIV_FORCE2)
809 		return parent_rate / 2;
810 
811 	err = regmap_bulk_read(output->data->regmap,
812 			SI5341_OUT_R_REG(output), r, 3);
813 	if (err < 0)
814 		return err;
815 
816 	/* Calculate value as 24-bit integer*/
817 	r_divider = r[2] << 16 | r[1] << 8 | r[0];
818 
819 	/* If Rx_REG is zero, the divider is disabled, so return a "0" rate */
820 	if (!r_divider)
821 		return 0;
822 
823 	/* Divider is 2*(Rx_REG+1) */
824 	r_divider += 1;
825 	r_divider <<= 1;
826 
827 
828 	return parent_rate / r_divider;
829 }
830 
831 static int si5341_output_clk_determine_rate(struct clk_hw *hw,
832 					    struct clk_rate_request *req)
833 {
834 	unsigned long rate = req->rate;
835 	unsigned long r;
836 
837 	if (!rate)
838 		return 0;
839 
840 	r = req->best_parent_rate >> 1;
841 
842 	/* If rate is an even divisor, no changes to parent required */
843 	if (r && !(r % rate))
844 		return 0;
845 
846 	if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) {
847 		if (rate > 200000000) {
848 			/* minimum r-divider is 2 */
849 			r = 2;
850 		} else {
851 			/* Take a parent frequency near 400 MHz */
852 			r = (400000000u / rate) & ~1;
853 		}
854 		req->best_parent_rate = r * rate;
855 	} else {
856 		/* We cannot change our parent's rate, report what we can do */
857 		r /= rate;
858 		rate = req->best_parent_rate / (r << 1);
859 	}
860 
861 	req->rate = rate;
862 	return 0;
863 }
864 
865 static int si5341_output_clk_set_rate(struct clk_hw *hw, unsigned long rate,
866 		unsigned long parent_rate)
867 {
868 	struct clk_si5341_output *output = to_clk_si5341_output(hw);
869 	u32 r_div;
870 	int err;
871 	u8 r[3];
872 
873 	if (!rate)
874 		return -EINVAL;
875 
876 	/* Frequency divider is (r_div + 1) * 2 */
877 	r_div = (parent_rate / rate) >> 1;
878 
879 	if (r_div <= 1)
880 		r_div = 0;
881 	else if (r_div >= BIT(24))
882 		r_div = BIT(24) - 1;
883 	else
884 		--r_div;
885 
886 	/* For a value of "2", we set the "OUT0_RDIV_FORCE2" bit */
887 	err = regmap_update_bits(output->data->regmap,
888 			SI5341_OUT_CONFIG(output),
889 			SI5341_OUT_CFG_RDIV_FORCE2,
890 			(r_div == 0) ? SI5341_OUT_CFG_RDIV_FORCE2 : 0);
891 	if (err < 0)
892 		return err;
893 
894 	/* Always write Rx_REG, because a zero value disables the divider */
895 	r[0] = r_div ? (r_div & 0xff) : 1;
896 	r[1] = (r_div >> 8) & 0xff;
897 	r[2] = (r_div >> 16) & 0xff;
898 	err = regmap_bulk_write(output->data->regmap,
899 			SI5341_OUT_R_REG(output), r, 3);
900 
901 	return 0;
902 }
903 
904 static int si5341_output_reparent(struct clk_si5341_output *output, u8 index)
905 {
906 	return regmap_update_bits(output->data->regmap,
907 		SI5341_OUT_MUX_SEL(output), 0x07, index);
908 }
909 
910 static int si5341_output_set_parent(struct clk_hw *hw, u8 index)
911 {
912 	struct clk_si5341_output *output = to_clk_si5341_output(hw);
913 
914 	if (index >= output->data->num_synth)
915 		return -EINVAL;
916 
917 	return si5341_output_reparent(output, index);
918 }
919 
920 static u8 si5341_output_get_parent(struct clk_hw *hw)
921 {
922 	struct clk_si5341_output *output = to_clk_si5341_output(hw);
923 	u32 val;
924 
925 	regmap_read(output->data->regmap, SI5341_OUT_MUX_SEL(output), &val);
926 
927 	return val & 0x7;
928 }
929 
930 static const struct clk_ops si5341_output_clk_ops = {
931 	.is_prepared = si5341_output_clk_is_on,
932 	.prepare = si5341_output_clk_prepare,
933 	.unprepare = si5341_output_clk_unprepare,
934 	.recalc_rate = si5341_output_clk_recalc_rate,
935 	.determine_rate = si5341_output_clk_determine_rate,
936 	.set_rate = si5341_output_clk_set_rate,
937 	.set_parent = si5341_output_set_parent,
938 	.get_parent = si5341_output_get_parent,
939 };
940 
941 /*
942  * The chip can be bought in a pre-programmed version, or one can program the
943  * NVM in the chip to boot up in a preset mode. This routine tries to determine
944  * if that's the case, or if we need to reset and program everything from
945  * scratch. Returns negative error, or true/false.
946  */
947 static int si5341_is_programmed_already(struct clk_si5341 *data)
948 {
949 	int err;
950 	u8 r[4];
951 
952 	/* Read the PLL divider value, it must have a non-zero value */
953 	err = regmap_bulk_read(data->regmap, SI5341_PLL_M_DEN,
954 			r, ARRAY_SIZE(r));
955 	if (err < 0)
956 		return err;
957 
958 	return !!get_unaligned_le32(r);
959 }
960 
961 static struct clk_hw *
962 of_clk_si5341_get(struct of_phandle_args *clkspec, void *_data)
963 {
964 	struct clk_si5341 *data = _data;
965 	unsigned int idx = clkspec->args[1];
966 	unsigned int group = clkspec->args[0];
967 
968 	switch (group) {
969 	case 0:
970 		if (idx >= data->num_outputs) {
971 			dev_err(&data->i2c_client->dev,
972 				"invalid output index %u\n", idx);
973 			return ERR_PTR(-EINVAL);
974 		}
975 		return &data->clk[idx].hw;
976 	case 1:
977 		if (idx >= data->num_synth) {
978 			dev_err(&data->i2c_client->dev,
979 				"invalid synthesizer index %u\n", idx);
980 			return ERR_PTR(-EINVAL);
981 		}
982 		return &data->synth[idx].hw;
983 	case 2:
984 		if (idx > 0) {
985 			dev_err(&data->i2c_client->dev,
986 				"invalid PLL index %u\n", idx);
987 			return ERR_PTR(-EINVAL);
988 		}
989 		return &data->hw;
990 	default:
991 		dev_err(&data->i2c_client->dev, "invalid group %u\n", group);
992 		return ERR_PTR(-EINVAL);
993 	}
994 }
995 
996 static int si5341_probe_chip_id(struct clk_si5341 *data)
997 {
998 	int err;
999 	u8 reg[4];
1000 	u16 model;
1001 
1002 	err = regmap_bulk_read(data->regmap, SI5341_PN_BASE, reg,
1003 				ARRAY_SIZE(reg));
1004 	if (err < 0) {
1005 		dev_err(&data->i2c_client->dev, "Failed to read chip ID\n");
1006 		return err;
1007 	}
1008 
1009 	model = get_unaligned_le16(reg);
1010 
1011 	dev_info(&data->i2c_client->dev, "Chip: %x Grade: %u Rev: %u\n",
1012 		 model, reg[2], reg[3]);
1013 
1014 	switch (model) {
1015 	case 0x5340:
1016 		data->num_outputs = SI5340_MAX_NUM_OUTPUTS;
1017 		data->num_synth = SI5340_NUM_SYNTH;
1018 		data->reg_output_offset = si5340_reg_output_offset;
1019 		data->reg_rdiv_offset = si5340_reg_rdiv_offset;
1020 		break;
1021 	case 0x5341:
1022 		data->num_outputs = SI5341_MAX_NUM_OUTPUTS;
1023 		data->num_synth = SI5341_NUM_SYNTH;
1024 		data->reg_output_offset = si5341_reg_output_offset;
1025 		data->reg_rdiv_offset = si5341_reg_rdiv_offset;
1026 		break;
1027 	case 0x5342:
1028 		data->num_outputs = SI5342_MAX_NUM_OUTPUTS;
1029 		data->num_synth = SI5342_NUM_SYNTH;
1030 		data->reg_output_offset = si5340_reg_output_offset;
1031 		data->reg_rdiv_offset = si5340_reg_rdiv_offset;
1032 		break;
1033 	case 0x5344:
1034 		data->num_outputs = SI5344_MAX_NUM_OUTPUTS;
1035 		data->num_synth = SI5344_NUM_SYNTH;
1036 		data->reg_output_offset = si5340_reg_output_offset;
1037 		data->reg_rdiv_offset = si5340_reg_rdiv_offset;
1038 		break;
1039 	case 0x5345:
1040 		data->num_outputs = SI5345_MAX_NUM_OUTPUTS;
1041 		data->num_synth = SI5345_NUM_SYNTH;
1042 		data->reg_output_offset = si5341_reg_output_offset;
1043 		data->reg_rdiv_offset = si5341_reg_rdiv_offset;
1044 		break;
1045 	default:
1046 		dev_err(&data->i2c_client->dev, "Model '%x' not supported\n",
1047 			model);
1048 		return -EINVAL;
1049 	}
1050 
1051 	data->chip_id = model;
1052 
1053 	return 0;
1054 }
1055 
1056 /* Read active settings into the regmap cache for later reference */
1057 static int si5341_read_settings(struct clk_si5341 *data)
1058 {
1059 	int err;
1060 	u8 i;
1061 	u8 r[10];
1062 
1063 	err = regmap_bulk_read(data->regmap, SI5341_PLL_M_NUM, r, 10);
1064 	if (err < 0)
1065 		return err;
1066 
1067 	err = regmap_bulk_read(data->regmap,
1068 				SI5341_SYNTH_N_CLK_TO_OUTX_EN, r, 3);
1069 	if (err < 0)
1070 		return err;
1071 
1072 	err = regmap_bulk_read(data->regmap,
1073 				SI5341_SYNTH_N_CLK_DIS, r, 1);
1074 	if (err < 0)
1075 		return err;
1076 
1077 	for (i = 0; i < data->num_synth; ++i) {
1078 		err = regmap_bulk_read(data->regmap,
1079 					SI5341_SYNTH_N_NUM(i), r, 10);
1080 		if (err < 0)
1081 			return err;
1082 	}
1083 
1084 	for (i = 0; i < data->num_outputs; ++i) {
1085 		err = regmap_bulk_read(data->regmap,
1086 					data->reg_output_offset[i], r, 4);
1087 		if (err < 0)
1088 			return err;
1089 
1090 		err = regmap_bulk_read(data->regmap,
1091 					data->reg_rdiv_offset[i], r, 3);
1092 		if (err < 0)
1093 			return err;
1094 	}
1095 
1096 	return 0;
1097 }
1098 
1099 static int si5341_write_multiple(struct clk_si5341 *data,
1100 	const struct si5341_reg_default *values, unsigned int num_values)
1101 {
1102 	unsigned int i;
1103 	int res;
1104 
1105 	for (i = 0; i < num_values; ++i) {
1106 		res = regmap_write(data->regmap,
1107 			values[i].address, values[i].value);
1108 		if (res < 0) {
1109 			dev_err(&data->i2c_client->dev,
1110 				"Failed to write %#x:%#x\n",
1111 				values[i].address, values[i].value);
1112 			return res;
1113 		}
1114 	}
1115 
1116 	return 0;
1117 }
1118 
1119 static const struct si5341_reg_default si5341_preamble[] = {
1120 	{ 0x0B25, 0x00 },
1121 	{ 0x0502, 0x01 },
1122 	{ 0x0505, 0x03 },
1123 	{ 0x0957, 0x17 },
1124 	{ 0x0B4E, 0x1A },
1125 };
1126 
1127 static const struct si5341_reg_default si5345_preamble[] = {
1128 	{ 0x0B25, 0x00 },
1129 	{ 0x0540, 0x01 },
1130 };
1131 
1132 static int si5341_send_preamble(struct clk_si5341 *data)
1133 {
1134 	int res;
1135 	u32 revision;
1136 
1137 	/* For revision 2 and up, the values are slightly different */
1138 	res = regmap_read(data->regmap, SI5341_DEVICE_REV, &revision);
1139 	if (res < 0)
1140 		return res;
1141 
1142 	/* Write "preamble" as specified by datasheet */
1143 	res = regmap_write(data->regmap, 0xB24, revision < 2 ? 0xD8 : 0xC0);
1144 	if (res < 0)
1145 		return res;
1146 
1147 	/* The si5342..si5345 require a different preamble */
1148 	if (data->chip_id > 0x5341)
1149 		res = si5341_write_multiple(data,
1150 			si5345_preamble, ARRAY_SIZE(si5345_preamble));
1151 	else
1152 		res = si5341_write_multiple(data,
1153 			si5341_preamble, ARRAY_SIZE(si5341_preamble));
1154 	if (res < 0)
1155 		return res;
1156 
1157 	/* Datasheet specifies a 300ms wait after sending the preamble */
1158 	msleep(300);
1159 
1160 	return 0;
1161 }
1162 
1163 /* Perform a soft reset and write post-amble */
1164 static int si5341_finalize_defaults(struct clk_si5341 *data)
1165 {
1166 	int res;
1167 	u32 revision;
1168 
1169 	res = regmap_write(data->regmap, SI5341_IO_VDD_SEL,
1170 			   data->iovdd_33 ? 1 : 0);
1171 	if (res < 0)
1172 		return res;
1173 
1174 	res = regmap_read(data->regmap, SI5341_DEVICE_REV, &revision);
1175 	if (res < 0)
1176 		return res;
1177 
1178 	dev_dbg(&data->i2c_client->dev, "%s rev=%u\n", __func__, revision);
1179 
1180 	res = regmap_write(data->regmap, SI5341_SOFT_RST, 0x01);
1181 	if (res < 0)
1182 		return res;
1183 
1184 	/* The si5342..si5345 have an additional post-amble */
1185 	if (data->chip_id > 0x5341) {
1186 		res = regmap_write(data->regmap, 0x540, 0x0);
1187 		if (res < 0)
1188 			return res;
1189 	}
1190 
1191 	/* Datasheet does not explain these nameless registers */
1192 	res = regmap_write(data->regmap, 0xB24, revision < 2 ? 0xDB : 0xC3);
1193 	if (res < 0)
1194 		return res;
1195 	res = regmap_write(data->regmap, 0x0B25, 0x02);
1196 	if (res < 0)
1197 		return res;
1198 
1199 	return 0;
1200 }
1201 
1202 
1203 static const struct regmap_range si5341_regmap_volatile_range[] = {
1204 	regmap_reg_range(0x000C, 0x0012), /* Status */
1205 	regmap_reg_range(0x001C, 0x001E), /* reset, finc/fdec */
1206 	regmap_reg_range(0x00E2, 0x00FE), /* NVM, interrupts, device ready */
1207 	/* Update bits for P divider and synth config */
1208 	regmap_reg_range(SI5341_PX_UPD, SI5341_PX_UPD),
1209 	regmap_reg_range(SI5341_SYNTH_N_UPD(0), SI5341_SYNTH_N_UPD(0)),
1210 	regmap_reg_range(SI5341_SYNTH_N_UPD(1), SI5341_SYNTH_N_UPD(1)),
1211 	regmap_reg_range(SI5341_SYNTH_N_UPD(2), SI5341_SYNTH_N_UPD(2)),
1212 	regmap_reg_range(SI5341_SYNTH_N_UPD(3), SI5341_SYNTH_N_UPD(3)),
1213 	regmap_reg_range(SI5341_SYNTH_N_UPD(4), SI5341_SYNTH_N_UPD(4)),
1214 };
1215 
1216 static const struct regmap_access_table si5341_regmap_volatile = {
1217 	.yes_ranges = si5341_regmap_volatile_range,
1218 	.n_yes_ranges = ARRAY_SIZE(si5341_regmap_volatile_range),
1219 };
1220 
1221 /* Pages 0, 1, 2, 3, 9, A, B are valid, so there are 12 pages */
1222 static const struct regmap_range_cfg si5341_regmap_ranges[] = {
1223 	{
1224 		.range_min = 0,
1225 		.range_max = SI5341_REGISTER_MAX,
1226 		.selector_reg = SI5341_PAGE,
1227 		.selector_mask = 0xff,
1228 		.selector_shift = 0,
1229 		.window_start = 0,
1230 		.window_len = 256,
1231 	},
1232 };
1233 
1234 static int si5341_wait_device_ready(struct i2c_client *client)
1235 {
1236 	int count;
1237 
1238 	/* Datasheet warns: Any attempt to read or write any register other
1239 	 * than DEVICE_READY before DEVICE_READY reads as 0x0F may corrupt the
1240 	 * NVM programming and may corrupt the register contents, as they are
1241 	 * read from NVM. Note that this includes accesses to the PAGE register.
1242 	 * Also: DEVICE_READY is available on every register page, so no page
1243 	 * change is needed to read it.
1244 	 * Do this outside regmap to avoid automatic PAGE register access.
1245 	 * May take up to 300ms to complete.
1246 	 */
1247 	for (count = 0; count < 15; ++count) {
1248 		s32 result = i2c_smbus_read_byte_data(client,
1249 						      SI5341_DEVICE_READY);
1250 		if (result < 0)
1251 			return result;
1252 		if (result == 0x0F)
1253 			return 0;
1254 		msleep(20);
1255 	}
1256 	dev_err(&client->dev, "timeout waiting for DEVICE_READY\n");
1257 	return -EIO;
1258 }
1259 
1260 static const struct regmap_config si5341_regmap_config = {
1261 	.reg_bits = 8,
1262 	.val_bits = 8,
1263 	.cache_type = REGCACHE_RBTREE,
1264 	.ranges = si5341_regmap_ranges,
1265 	.num_ranges = ARRAY_SIZE(si5341_regmap_ranges),
1266 	.max_register = SI5341_REGISTER_MAX,
1267 	.volatile_table = &si5341_regmap_volatile,
1268 };
1269 
1270 static int si5341_dt_parse_dt(struct clk_si5341 *data,
1271 			      struct clk_si5341_output_config *config)
1272 {
1273 	struct device_node *child;
1274 	struct device_node *np = data->i2c_client->dev.of_node;
1275 	u32 num;
1276 	u32 val;
1277 
1278 	memset(config, 0, sizeof(struct clk_si5341_output_config) *
1279 				SI5341_MAX_NUM_OUTPUTS);
1280 
1281 	for_each_child_of_node(np, child) {
1282 		if (of_property_read_u32(child, "reg", &num)) {
1283 			dev_err(&data->i2c_client->dev, "missing reg property of %s\n",
1284 				child->name);
1285 			goto put_child;
1286 		}
1287 
1288 		if (num >= SI5341_MAX_NUM_OUTPUTS) {
1289 			dev_err(&data->i2c_client->dev, "invalid clkout %d\n", num);
1290 			goto put_child;
1291 		}
1292 
1293 		if (!of_property_read_u32(child, "silabs,format", &val)) {
1294 			/* Set cm and ampl conservatively to 3v3 settings */
1295 			switch (val) {
1296 			case 1: /* normal differential */
1297 				config[num].out_cm_ampl_bits = 0x33;
1298 				break;
1299 			case 2: /* low-power differential */
1300 				config[num].out_cm_ampl_bits = 0x13;
1301 				break;
1302 			case 4: /* LVCMOS */
1303 				config[num].out_cm_ampl_bits = 0x33;
1304 				/* Set SI recommended impedance for LVCMOS */
1305 				config[num].out_format_drv_bits |= 0xc0;
1306 				break;
1307 			default:
1308 				dev_err(&data->i2c_client->dev,
1309 					"invalid silabs,format %u for %u\n",
1310 					val, num);
1311 				goto put_child;
1312 			}
1313 			config[num].out_format_drv_bits &= ~0x07;
1314 			config[num].out_format_drv_bits |= val & 0x07;
1315 			/* Always enable the SYNC feature */
1316 			config[num].out_format_drv_bits |= 0x08;
1317 		}
1318 
1319 		if (!of_property_read_u32(child, "silabs,common-mode", &val)) {
1320 			if (val > 0xf) {
1321 				dev_err(&data->i2c_client->dev,
1322 					"invalid silabs,common-mode %u\n",
1323 					val);
1324 				goto put_child;
1325 			}
1326 			config[num].out_cm_ampl_bits &= 0xf0;
1327 			config[num].out_cm_ampl_bits |= val & 0x0f;
1328 		}
1329 
1330 		if (!of_property_read_u32(child, "silabs,amplitude", &val)) {
1331 			if (val > 0xf) {
1332 				dev_err(&data->i2c_client->dev,
1333 					"invalid silabs,amplitude %u\n",
1334 					val);
1335 				goto put_child;
1336 			}
1337 			config[num].out_cm_ampl_bits &= 0x0f;
1338 			config[num].out_cm_ampl_bits |= (val << 4) & 0xf0;
1339 		}
1340 
1341 		if (of_property_read_bool(child, "silabs,disable-high"))
1342 			config[num].out_format_drv_bits |= 0x10;
1343 
1344 		config[num].synth_master =
1345 			of_property_read_bool(child, "silabs,synth-master");
1346 
1347 		config[num].always_on =
1348 			of_property_read_bool(child, "always-on");
1349 
1350 		config[num].vdd_sel_bits = 0x08;
1351 		if (data->clk[num].vddo_reg) {
1352 			int vdd = regulator_get_voltage(data->clk[num].vddo_reg);
1353 
1354 			switch (vdd) {
1355 			case 3300000:
1356 				config[num].vdd_sel_bits |= 0 << 4;
1357 				break;
1358 			case 1800000:
1359 				config[num].vdd_sel_bits |= 1 << 4;
1360 				break;
1361 			case 2500000:
1362 				config[num].vdd_sel_bits |= 2 << 4;
1363 				break;
1364 			default:
1365 				dev_err(&data->i2c_client->dev,
1366 					"unsupported vddo voltage %d for %s\n",
1367 					vdd, child->name);
1368 				goto put_child;
1369 			}
1370 		} else {
1371 			/* chip seems to default to 2.5V when not set */
1372 			dev_warn(&data->i2c_client->dev,
1373 				"no regulator set, defaulting vdd_sel to 2.5V for %s\n",
1374 				child->name);
1375 			config[num].vdd_sel_bits |= 2 << 4;
1376 		}
1377 	}
1378 
1379 	return 0;
1380 
1381 put_child:
1382 	of_node_put(child);
1383 	return -EINVAL;
1384 }
1385 
1386 /*
1387  * If not pre-configured, calculate and set the PLL configuration manually.
1388  * For low-jitter performance, the PLL should be set such that the synthesizers
1389  * only need integer division.
1390  * Without any user guidance, we'll set the PLL to 14GHz, which still allows
1391  * the chip to generate any frequency on its outputs, but jitter performance
1392  * may be sub-optimal.
1393  */
1394 static int si5341_initialize_pll(struct clk_si5341 *data)
1395 {
1396 	struct device_node *np = data->i2c_client->dev.of_node;
1397 	u32 m_num = 0;
1398 	u32 m_den = 0;
1399 	int sel;
1400 
1401 	if (of_property_read_u32(np, "silabs,pll-m-num", &m_num)) {
1402 		dev_err(&data->i2c_client->dev,
1403 			"PLL configuration requires silabs,pll-m-num\n");
1404 	}
1405 	if (of_property_read_u32(np, "silabs,pll-m-den", &m_den)) {
1406 		dev_err(&data->i2c_client->dev,
1407 			"PLL configuration requires silabs,pll-m-den\n");
1408 	}
1409 
1410 	if (!m_num || !m_den) {
1411 		dev_err(&data->i2c_client->dev,
1412 			"PLL configuration invalid, assume 14GHz\n");
1413 		sel = si5341_clk_get_selected_input(data);
1414 		if (sel < 0)
1415 			return sel;
1416 
1417 		m_den = clk_get_rate(data->input_clk[sel]) / 10;
1418 		m_num = 1400000000;
1419 	}
1420 
1421 	return si5341_encode_44_32(data->regmap,
1422 			SI5341_PLL_M_NUM, m_num, m_den);
1423 }
1424 
1425 static int si5341_clk_select_active_input(struct clk_si5341 *data)
1426 {
1427 	int res;
1428 	int err;
1429 	int i;
1430 
1431 	res = si5341_clk_get_selected_input(data);
1432 	if (res < 0)
1433 		return res;
1434 
1435 	/* If the current register setting is invalid, pick the first input */
1436 	if (!data->input_clk[res]) {
1437 		dev_dbg(&data->i2c_client->dev,
1438 			"Input %d not connected, rerouting\n", res);
1439 		res = -ENODEV;
1440 		for (i = 0; i < SI5341_NUM_INPUTS; ++i) {
1441 			if (data->input_clk[i]) {
1442 				res = i;
1443 				break;
1444 			}
1445 		}
1446 		if (res < 0) {
1447 			dev_err(&data->i2c_client->dev,
1448 				"No clock input available\n");
1449 			return res;
1450 		}
1451 	}
1452 
1453 	/* Make sure the selected clock is also enabled and routed */
1454 	err = si5341_clk_reparent(data, res);
1455 	if (err < 0)
1456 		return err;
1457 
1458 	err = clk_prepare_enable(data->input_clk[res]);
1459 	if (err < 0)
1460 		return err;
1461 
1462 	return res;
1463 }
1464 
1465 static ssize_t input_present_show(struct device *dev,
1466 				  struct device_attribute *attr,
1467 				  char *buf)
1468 {
1469 	struct clk_si5341 *data = dev_get_drvdata(dev);
1470 	u32 status;
1471 	int res = regmap_read(data->regmap, SI5341_STATUS, &status);
1472 
1473 	if (res < 0)
1474 		return res;
1475 	res = !(status & SI5341_STATUS_LOSREF);
1476 	return sysfs_emit(buf, "%d\n", res);
1477 }
1478 static DEVICE_ATTR_RO(input_present);
1479 
1480 static ssize_t input_present_sticky_show(struct device *dev,
1481 					 struct device_attribute *attr,
1482 					 char *buf)
1483 {
1484 	struct clk_si5341 *data = dev_get_drvdata(dev);
1485 	u32 status;
1486 	int res = regmap_read(data->regmap, SI5341_STATUS_STICKY, &status);
1487 
1488 	if (res < 0)
1489 		return res;
1490 	res = !(status & SI5341_STATUS_LOSREF);
1491 	return sysfs_emit(buf, "%d\n", res);
1492 }
1493 static DEVICE_ATTR_RO(input_present_sticky);
1494 
1495 static ssize_t pll_locked_show(struct device *dev,
1496 			       struct device_attribute *attr,
1497 			       char *buf)
1498 {
1499 	struct clk_si5341 *data = dev_get_drvdata(dev);
1500 	u32 status;
1501 	int res = regmap_read(data->regmap, SI5341_STATUS, &status);
1502 
1503 	if (res < 0)
1504 		return res;
1505 	res = !(status & SI5341_STATUS_LOL);
1506 	return sysfs_emit(buf, "%d\n", res);
1507 }
1508 static DEVICE_ATTR_RO(pll_locked);
1509 
1510 static ssize_t pll_locked_sticky_show(struct device *dev,
1511 				      struct device_attribute *attr,
1512 				      char *buf)
1513 {
1514 	struct clk_si5341 *data = dev_get_drvdata(dev);
1515 	u32 status;
1516 	int res = regmap_read(data->regmap, SI5341_STATUS_STICKY, &status);
1517 
1518 	if (res < 0)
1519 		return res;
1520 	res = !(status & SI5341_STATUS_LOL);
1521 	return sysfs_emit(buf, "%d\n", res);
1522 }
1523 static DEVICE_ATTR_RO(pll_locked_sticky);
1524 
1525 static ssize_t clear_sticky_store(struct device *dev,
1526 				  struct device_attribute *attr,
1527 				  const char *buf, size_t count)
1528 {
1529 	struct clk_si5341 *data = dev_get_drvdata(dev);
1530 	long val;
1531 
1532 	if (kstrtol(buf, 10, &val))
1533 		return -EINVAL;
1534 	if (val) {
1535 		int res = regmap_write(data->regmap, SI5341_STATUS_STICKY, 0);
1536 
1537 		if (res < 0)
1538 			return res;
1539 	}
1540 	return count;
1541 }
1542 static DEVICE_ATTR_WO(clear_sticky);
1543 
1544 static const struct attribute *si5341_attributes[] = {
1545 	&dev_attr_input_present.attr,
1546 	&dev_attr_input_present_sticky.attr,
1547 	&dev_attr_pll_locked.attr,
1548 	&dev_attr_pll_locked_sticky.attr,
1549 	&dev_attr_clear_sticky.attr,
1550 	NULL
1551 };
1552 
1553 static int si5341_probe(struct i2c_client *client)
1554 {
1555 	struct clk_si5341 *data;
1556 	struct clk_init_data init;
1557 	struct clk *input;
1558 	const char *root_clock_name;
1559 	const char *synth_clock_names[SI5341_NUM_SYNTH] = { NULL };
1560 	int err;
1561 	unsigned int i;
1562 	struct clk_si5341_output_config config[SI5341_MAX_NUM_OUTPUTS];
1563 	bool initialization_required;
1564 	u32 status;
1565 
1566 	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
1567 	if (!data)
1568 		return -ENOMEM;
1569 
1570 	data->i2c_client = client;
1571 
1572 	/* Must be done before otherwise touching hardware */
1573 	err = si5341_wait_device_ready(client);
1574 	if (err)
1575 		return err;
1576 
1577 	for (i = 0; i < SI5341_NUM_INPUTS; ++i) {
1578 		input = devm_clk_get(&client->dev, si5341_input_clock_names[i]);
1579 		if (IS_ERR(input)) {
1580 			if (PTR_ERR(input) == -EPROBE_DEFER)
1581 				return -EPROBE_DEFER;
1582 			data->input_clk_name[i] = si5341_input_clock_names[i];
1583 		} else {
1584 			data->input_clk[i] = input;
1585 			data->input_clk_name[i] = __clk_get_name(input);
1586 		}
1587 	}
1588 
1589 	for (i = 0; i < SI5341_MAX_NUM_OUTPUTS; ++i) {
1590 		char reg_name[10];
1591 
1592 		snprintf(reg_name, sizeof(reg_name), "vddo%d", i);
1593 		data->clk[i].vddo_reg = devm_regulator_get_optional(
1594 			&client->dev, reg_name);
1595 		if (IS_ERR(data->clk[i].vddo_reg)) {
1596 			err = PTR_ERR(data->clk[i].vddo_reg);
1597 			data->clk[i].vddo_reg = NULL;
1598 			if (err == -ENODEV)
1599 				continue;
1600 			goto cleanup;
1601 		} else {
1602 			err = regulator_enable(data->clk[i].vddo_reg);
1603 			if (err) {
1604 				dev_err(&client->dev,
1605 					"failed to enable %s regulator: %d\n",
1606 					reg_name, err);
1607 				data->clk[i].vddo_reg = NULL;
1608 				goto cleanup;
1609 			}
1610 		}
1611 	}
1612 
1613 	err = si5341_dt_parse_dt(data, config);
1614 	if (err)
1615 		goto cleanup;
1616 
1617 	if (of_property_read_string(client->dev.of_node, "clock-output-names",
1618 			&init.name))
1619 		init.name = client->dev.of_node->name;
1620 	root_clock_name = init.name;
1621 
1622 	data->regmap = devm_regmap_init_i2c(client, &si5341_regmap_config);
1623 	if (IS_ERR(data->regmap)) {
1624 		err = PTR_ERR(data->regmap);
1625 		goto cleanup;
1626 	}
1627 
1628 	i2c_set_clientdata(client, data);
1629 
1630 	err = si5341_probe_chip_id(data);
1631 	if (err < 0)
1632 		goto cleanup;
1633 
1634 	if (of_property_read_bool(client->dev.of_node, "silabs,reprogram")) {
1635 		initialization_required = true;
1636 	} else {
1637 		err = si5341_is_programmed_already(data);
1638 		if (err < 0)
1639 			goto cleanup;
1640 
1641 		initialization_required = !err;
1642 	}
1643 	data->xaxb_ext_clk = of_property_read_bool(client->dev.of_node,
1644 						   "silabs,xaxb-ext-clk");
1645 	data->iovdd_33 = of_property_read_bool(client->dev.of_node,
1646 					       "silabs,iovdd-33");
1647 
1648 	if (initialization_required) {
1649 		/* Populate the regmap cache in preparation for "cache only" */
1650 		err = si5341_read_settings(data);
1651 		if (err < 0)
1652 			goto cleanup;
1653 
1654 		err = si5341_send_preamble(data);
1655 		if (err < 0)
1656 			goto cleanup;
1657 
1658 		/*
1659 		 * We intend to send all 'final' register values in a single
1660 		 * transaction. So cache all register writes until we're done
1661 		 * configuring.
1662 		 */
1663 		regcache_cache_only(data->regmap, true);
1664 
1665 		/* Write the configuration pairs from the firmware blob */
1666 		err = si5341_write_multiple(data, si5341_reg_defaults,
1667 					ARRAY_SIZE(si5341_reg_defaults));
1668 		if (err < 0)
1669 			goto cleanup;
1670 	}
1671 
1672 	/* Input must be up and running at this point */
1673 	err = si5341_clk_select_active_input(data);
1674 	if (err < 0)
1675 		goto cleanup;
1676 
1677 	if (initialization_required) {
1678 		/* PLL configuration is required */
1679 		err = si5341_initialize_pll(data);
1680 		if (err < 0)
1681 			goto cleanup;
1682 	}
1683 
1684 	/* Register the PLL */
1685 	init.parent_names = data->input_clk_name;
1686 	init.num_parents = SI5341_NUM_INPUTS;
1687 	init.ops = &si5341_clk_ops;
1688 	init.flags = 0;
1689 	data->hw.init = &init;
1690 
1691 	err = devm_clk_hw_register(&client->dev, &data->hw);
1692 	if (err) {
1693 		dev_err(&client->dev, "clock registration failed\n");
1694 		goto cleanup;
1695 	}
1696 
1697 	init.num_parents = 1;
1698 	init.parent_names = &root_clock_name;
1699 	init.ops = &si5341_synth_clk_ops;
1700 	for (i = 0; i < data->num_synth; ++i) {
1701 		synth_clock_names[i] = devm_kasprintf(&client->dev, GFP_KERNEL,
1702 				"%s.N%u", client->dev.of_node->name, i);
1703 		if (!synth_clock_names[i]) {
1704 			err = -ENOMEM;
1705 			goto free_clk_names;
1706 		}
1707 		init.name = synth_clock_names[i];
1708 		data->synth[i].index = i;
1709 		data->synth[i].data = data;
1710 		data->synth[i].hw.init = &init;
1711 		err = devm_clk_hw_register(&client->dev, &data->synth[i].hw);
1712 		if (err) {
1713 			dev_err(&client->dev,
1714 				"synth N%u registration failed\n", i);
1715 			goto free_clk_names;
1716 		}
1717 	}
1718 
1719 	init.num_parents = data->num_synth;
1720 	init.parent_names = synth_clock_names;
1721 	init.ops = &si5341_output_clk_ops;
1722 	for (i = 0; i < data->num_outputs; ++i) {
1723 		init.name = kasprintf(GFP_KERNEL, "%s.%d",
1724 			client->dev.of_node->name, i);
1725 		if (!init.name) {
1726 			err = -ENOMEM;
1727 			goto free_clk_names;
1728 		}
1729 		init.flags = config[i].synth_master ? CLK_SET_RATE_PARENT : 0;
1730 		data->clk[i].index = i;
1731 		data->clk[i].data = data;
1732 		data->clk[i].hw.init = &init;
1733 		if (config[i].out_format_drv_bits & 0x07) {
1734 			regmap_write(data->regmap,
1735 				SI5341_OUT_FORMAT(&data->clk[i]),
1736 				config[i].out_format_drv_bits);
1737 			regmap_write(data->regmap,
1738 				SI5341_OUT_CM(&data->clk[i]),
1739 				config[i].out_cm_ampl_bits);
1740 			regmap_update_bits(data->regmap,
1741 				SI5341_OUT_MUX_SEL(&data->clk[i]),
1742 				SI5341_OUT_MUX_VDD_SEL_MASK,
1743 				config[i].vdd_sel_bits);
1744 		}
1745 		err = devm_clk_hw_register(&client->dev, &data->clk[i].hw);
1746 		kfree(init.name); /* clock framework made a copy of the name */
1747 		if (err) {
1748 			dev_err(&client->dev,
1749 				"output %u registration failed\n", i);
1750 			goto free_clk_names;
1751 		}
1752 		if (config[i].always_on)
1753 			clk_prepare(data->clk[i].hw.clk);
1754 	}
1755 
1756 	err = devm_of_clk_add_hw_provider(&client->dev, of_clk_si5341_get,
1757 			data);
1758 	if (err) {
1759 		dev_err(&client->dev, "unable to add clk provider\n");
1760 		goto free_clk_names;
1761 	}
1762 
1763 	if (initialization_required) {
1764 		/* Synchronize */
1765 		regcache_cache_only(data->regmap, false);
1766 		err = regcache_sync(data->regmap);
1767 		if (err < 0)
1768 			goto free_clk_names;
1769 
1770 		err = si5341_finalize_defaults(data);
1771 		if (err < 0)
1772 			goto free_clk_names;
1773 	}
1774 
1775 	/* wait for device to report input clock present and PLL lock */
1776 	err = regmap_read_poll_timeout(data->regmap, SI5341_STATUS, status,
1777 		!(status & (SI5341_STATUS_LOSREF | SI5341_STATUS_LOL)),
1778 	       10000, 250000);
1779 	if (err) {
1780 		dev_err(&client->dev, "Error waiting for input clock or PLL lock\n");
1781 		goto free_clk_names;
1782 	}
1783 
1784 	/* clear sticky alarm bits from initialization */
1785 	err = regmap_write(data->regmap, SI5341_STATUS_STICKY, 0);
1786 	if (err) {
1787 		dev_err(&client->dev, "unable to clear sticky status\n");
1788 		goto free_clk_names;
1789 	}
1790 
1791 	err = sysfs_create_files(&client->dev.kobj, si5341_attributes);
1792 	if (err)
1793 		dev_err(&client->dev, "unable to create sysfs files\n");
1794 
1795 free_clk_names:
1796 	/* Free the names, clk framework makes copies */
1797 	for (i = 0; i < data->num_synth; ++i)
1798 		 devm_kfree(&client->dev, (void *)synth_clock_names[i]);
1799 
1800 cleanup:
1801 	if (err) {
1802 		for (i = 0; i < SI5341_MAX_NUM_OUTPUTS; ++i) {
1803 			if (data->clk[i].vddo_reg)
1804 				regulator_disable(data->clk[i].vddo_reg);
1805 		}
1806 	}
1807 	return err;
1808 }
1809 
1810 static void si5341_remove(struct i2c_client *client)
1811 {
1812 	struct clk_si5341 *data = i2c_get_clientdata(client);
1813 	int i;
1814 
1815 	sysfs_remove_files(&client->dev.kobj, si5341_attributes);
1816 
1817 	for (i = 0; i < SI5341_MAX_NUM_OUTPUTS; ++i) {
1818 		if (data->clk[i].vddo_reg)
1819 			regulator_disable(data->clk[i].vddo_reg);
1820 	}
1821 }
1822 
1823 static const struct i2c_device_id si5341_id[] = {
1824 	{ "si5340", 0 },
1825 	{ "si5341", 1 },
1826 	{ "si5342", 2 },
1827 	{ "si5344", 4 },
1828 	{ "si5345", 5 },
1829 	{ }
1830 };
1831 MODULE_DEVICE_TABLE(i2c, si5341_id);
1832 
1833 static const struct of_device_id clk_si5341_of_match[] = {
1834 	{ .compatible = "silabs,si5340" },
1835 	{ .compatible = "silabs,si5341" },
1836 	{ .compatible = "silabs,si5342" },
1837 	{ .compatible = "silabs,si5344" },
1838 	{ .compatible = "silabs,si5345" },
1839 	{ }
1840 };
1841 MODULE_DEVICE_TABLE(of, clk_si5341_of_match);
1842 
1843 static struct i2c_driver si5341_driver = {
1844 	.driver = {
1845 		.name = "si5341",
1846 		.of_match_table = clk_si5341_of_match,
1847 	},
1848 	.probe		= si5341_probe,
1849 	.remove		= si5341_remove,
1850 	.id_table	= si5341_id,
1851 };
1852 module_i2c_driver(si5341_driver);
1853 
1854 MODULE_AUTHOR("Mike Looijmans <mike.looijmans@topic.nl>");
1855 MODULE_DESCRIPTION("Si5341 driver");
1856 MODULE_LICENSE("GPL");
1857