1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * STMicroelectronics STM32 USB PHY Controller driver
4  *
5  * Copyright (C) 2018 STMicroelectronics
6  * Author(s): Amelie Delaunay <amelie.delaunay@st.com>.
7  */
8 #include <linux/bitfield.h>
9 #include <linux/clk.h>
10 #include <linux/clk-provider.h>
11 #include <linux/delay.h>
12 #include <linux/iopoll.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/of_platform.h>
16 #include <linux/phy/phy.h>
17 #include <linux/reset.h>
18 #include <linux/units.h>
19 
20 #define STM32_USBPHYC_PLL	0x0
21 #define STM32_USBPHYC_MISC	0x8
22 #define STM32_USBPHYC_MONITOR(X) (0x108 + ((X) * 0x100))
23 #define STM32_USBPHYC_TUNE(X)	(0x10C + ((X) * 0x100))
24 #define STM32_USBPHYC_VERSION	0x3F4
25 
26 /* STM32_USBPHYC_PLL bit fields */
27 #define PLLNDIV			GENMASK(6, 0)
28 #define PLLFRACIN		GENMASK(25, 10)
29 #define PLLEN			BIT(26)
30 #define PLLSTRB			BIT(27)
31 #define PLLSTRBYP		BIT(28)
32 #define PLLFRACCTL		BIT(29)
33 #define PLLDITHEN0		BIT(30)
34 #define PLLDITHEN1		BIT(31)
35 
36 /* STM32_USBPHYC_MISC bit fields */
37 #define SWITHOST		BIT(0)
38 
39 /* STM32_USBPHYC_MONITOR bit fields */
40 #define STM32_USBPHYC_MON_OUT	GENMASK(3, 0)
41 #define STM32_USBPHYC_MON_SEL	GENMASK(8, 4)
42 #define STM32_USBPHYC_MON_SEL_LOCKP 0x1F
43 #define STM32_USBPHYC_MON_OUT_LOCKP BIT(3)
44 
45 /* STM32_USBPHYC_TUNE bit fields */
46 #define INCURREN		BIT(0)
47 #define INCURRINT		BIT(1)
48 #define LFSCAPEN		BIT(2)
49 #define HSDRVSLEW		BIT(3)
50 #define HSDRVDCCUR		BIT(4)
51 #define HSDRVDCLEV		BIT(5)
52 #define HSDRVCURINCR		BIT(6)
53 #define FSDRVRFADJ		BIT(7)
54 #define HSDRVRFRED		BIT(8)
55 #define HSDRVCHKITRM		GENMASK(12, 9)
56 #define HSDRVCHKZTRM		GENMASK(14, 13)
57 #define OTPCOMP			GENMASK(19, 15)
58 #define SQLCHCTL		GENMASK(21, 20)
59 #define HDRXGNEQEN		BIT(22)
60 #define HSRXOFF			GENMASK(24, 23)
61 #define HSFALLPREEM		BIT(25)
62 #define SHTCCTCTLPROT		BIT(26)
63 #define STAGSEL			BIT(27)
64 
65 enum boosting_vals {
66 	BOOST_1000_UA = 1000,
67 	BOOST_2000_UA = 2000,
68 };
69 
70 enum dc_level_vals {
71 	DC_NOMINAL,
72 	DC_PLUS_5_TO_7_MV,
73 	DC_PLUS_10_TO_14_MV,
74 	DC_MINUS_5_TO_7_MV,
75 	DC_MAX,
76 };
77 
78 enum current_trim {
79 	CUR_NOMINAL,
80 	CUR_PLUS_1_56_PCT,
81 	CUR_PLUS_3_12_PCT,
82 	CUR_PLUS_4_68_PCT,
83 	CUR_PLUS_6_24_PCT,
84 	CUR_PLUS_7_8_PCT,
85 	CUR_PLUS_9_36_PCT,
86 	CUR_PLUS_10_92_PCT,
87 	CUR_PLUS_12_48_PCT,
88 	CUR_PLUS_14_04_PCT,
89 	CUR_PLUS_15_6_PCT,
90 	CUR_PLUS_17_16_PCT,
91 	CUR_PLUS_19_01_PCT,
92 	CUR_PLUS_20_58_PCT,
93 	CUR_PLUS_22_16_PCT,
94 	CUR_PLUS_23_73_PCT,
95 	CUR_MAX,
96 };
97 
98 enum impedance_trim {
99 	IMP_NOMINAL,
100 	IMP_MINUS_2_OHMS,
101 	IMP_MINUS_4_OMHS,
102 	IMP_MINUS_6_OHMS,
103 	IMP_MAX,
104 };
105 
106 enum squelch_level {
107 	SQLCH_NOMINAL,
108 	SQLCH_PLUS_7_MV,
109 	SQLCH_MINUS_5_MV,
110 	SQLCH_PLUS_14_MV,
111 	SQLCH_MAX,
112 };
113 
114 enum rx_offset {
115 	NO_RX_OFFSET,
116 	RX_OFFSET_PLUS_5_MV,
117 	RX_OFFSET_PLUS_10_MV,
118 	RX_OFFSET_MINUS_5_MV,
119 	RX_OFFSET_MAX,
120 };
121 
122 /* STM32_USBPHYC_VERSION bit fields */
123 #define MINREV			GENMASK(3, 0)
124 #define MAJREV			GENMASK(7, 4)
125 
126 #define PLL_FVCO_MHZ		2880
127 #define PLL_INFF_MIN_RATE_HZ	19200000
128 #define PLL_INFF_MAX_RATE_HZ	38400000
129 
130 struct pll_params {
131 	u8 ndiv;
132 	u16 frac;
133 };
134 
135 struct stm32_usbphyc_phy {
136 	struct phy *phy;
137 	struct stm32_usbphyc *usbphyc;
138 	struct regulator *vbus;
139 	u32 index;
140 	bool active;
141 	u32 tune;
142 };
143 
144 struct stm32_usbphyc {
145 	struct device *dev;
146 	void __iomem *base;
147 	struct clk *clk;
148 	struct reset_control *rst;
149 	struct stm32_usbphyc_phy **phys;
150 	int nphys;
151 	struct regulator *vdda1v1;
152 	struct regulator *vdda1v8;
153 	atomic_t n_pll_cons;
154 	struct clk_hw clk48_hw;
155 	int switch_setup;
156 };
157 
158 static inline void stm32_usbphyc_set_bits(void __iomem *reg, u32 bits)
159 {
160 	writel_relaxed(readl_relaxed(reg) | bits, reg);
161 }
162 
163 static inline void stm32_usbphyc_clr_bits(void __iomem *reg, u32 bits)
164 {
165 	writel_relaxed(readl_relaxed(reg) & ~bits, reg);
166 }
167 
168 static int stm32_usbphyc_regulators_enable(struct stm32_usbphyc *usbphyc)
169 {
170 	int ret;
171 
172 	ret = regulator_enable(usbphyc->vdda1v1);
173 	if (ret)
174 		return ret;
175 
176 	ret = regulator_enable(usbphyc->vdda1v8);
177 	if (ret)
178 		goto vdda1v1_disable;
179 
180 	return 0;
181 
182 vdda1v1_disable:
183 	regulator_disable(usbphyc->vdda1v1);
184 
185 	return ret;
186 }
187 
188 static int stm32_usbphyc_regulators_disable(struct stm32_usbphyc *usbphyc)
189 {
190 	int ret;
191 
192 	ret = regulator_disable(usbphyc->vdda1v8);
193 	if (ret)
194 		return ret;
195 
196 	ret = regulator_disable(usbphyc->vdda1v1);
197 	if (ret)
198 		return ret;
199 
200 	return 0;
201 }
202 
203 static void stm32_usbphyc_get_pll_params(u32 clk_rate,
204 					 struct pll_params *pll_params)
205 {
206 	unsigned long long fvco, ndiv, frac;
207 
208 	/*    _
209 	 *   | FVCO = INFF*2*(NDIV + FRACT/2^16) when DITHER_DISABLE[1] = 1
210 	 *   | FVCO = 2880MHz
211 	 *  <
212 	 *   | NDIV = integer part of input bits to set the LDF
213 	 *   |_FRACT = fractional part of input bits to set the LDF
214 	 *  =>	PLLNDIV = integer part of (FVCO / (INFF*2))
215 	 *  =>	PLLFRACIN = fractional part of(FVCO / INFF*2) * 2^16
216 	 * <=>  PLLFRACIN = ((FVCO / (INFF*2)) - PLLNDIV) * 2^16
217 	 */
218 	fvco = (unsigned long long)PLL_FVCO_MHZ * HZ_PER_MHZ;
219 
220 	ndiv = fvco;
221 	do_div(ndiv, (clk_rate * 2));
222 	pll_params->ndiv = (u8)ndiv;
223 
224 	frac = fvco * (1 << 16);
225 	do_div(frac, (clk_rate * 2));
226 	frac = frac - (ndiv * (1 << 16));
227 	pll_params->frac = (u16)frac;
228 }
229 
230 static int stm32_usbphyc_pll_init(struct stm32_usbphyc *usbphyc)
231 {
232 	struct pll_params pll_params;
233 	u32 clk_rate = clk_get_rate(usbphyc->clk);
234 	u32 ndiv, frac;
235 	u32 usbphyc_pll;
236 
237 	if ((clk_rate < PLL_INFF_MIN_RATE_HZ) ||
238 	    (clk_rate > PLL_INFF_MAX_RATE_HZ)) {
239 		dev_err(usbphyc->dev, "input clk freq (%dHz) out of range\n",
240 			clk_rate);
241 		return -EINVAL;
242 	}
243 
244 	stm32_usbphyc_get_pll_params(clk_rate, &pll_params);
245 	ndiv = FIELD_PREP(PLLNDIV, pll_params.ndiv);
246 	frac = FIELD_PREP(PLLFRACIN, pll_params.frac);
247 
248 	usbphyc_pll = PLLDITHEN1 | PLLDITHEN0 | PLLSTRBYP | ndiv;
249 
250 	if (pll_params.frac)
251 		usbphyc_pll |= PLLFRACCTL | frac;
252 
253 	writel_relaxed(usbphyc_pll, usbphyc->base + STM32_USBPHYC_PLL);
254 
255 	dev_dbg(usbphyc->dev, "input clk freq=%dHz, ndiv=%lu, frac=%lu\n",
256 		clk_rate, FIELD_GET(PLLNDIV, usbphyc_pll),
257 		FIELD_GET(PLLFRACIN, usbphyc_pll));
258 
259 	return 0;
260 }
261 
262 static int __stm32_usbphyc_pll_disable(struct stm32_usbphyc *usbphyc)
263 {
264 	void __iomem *pll_reg = usbphyc->base + STM32_USBPHYC_PLL;
265 	u32 pllen;
266 
267 	stm32_usbphyc_clr_bits(pll_reg, PLLEN);
268 
269 	/* Wait for minimum width of powerdown pulse (ENABLE = Low) */
270 	if (readl_relaxed_poll_timeout(pll_reg, pllen, !(pllen & PLLEN), 5, 50))
271 		dev_err(usbphyc->dev, "PLL not reset\n");
272 
273 	return stm32_usbphyc_regulators_disable(usbphyc);
274 }
275 
276 static int stm32_usbphyc_pll_disable(struct stm32_usbphyc *usbphyc)
277 {
278 	/* Check if a phy port is still active or clk48 in use */
279 	if (atomic_dec_return(&usbphyc->n_pll_cons) > 0)
280 		return 0;
281 
282 	return __stm32_usbphyc_pll_disable(usbphyc);
283 }
284 
285 static int stm32_usbphyc_pll_enable(struct stm32_usbphyc *usbphyc)
286 {
287 	void __iomem *pll_reg = usbphyc->base + STM32_USBPHYC_PLL;
288 	bool pllen = readl_relaxed(pll_reg) & PLLEN;
289 	int ret;
290 
291 	/*
292 	 * Check if a phy port or clk48 prepare has configured the pll
293 	 * and ensure the PLL is enabled
294 	 */
295 	if (atomic_inc_return(&usbphyc->n_pll_cons) > 1 && pllen)
296 		return 0;
297 
298 	if (pllen) {
299 		/*
300 		 * PLL shouldn't be enabled without known consumer,
301 		 * disable it and reinit n_pll_cons
302 		 */
303 		dev_warn(usbphyc->dev, "PLL enabled without known consumers\n");
304 
305 		ret = __stm32_usbphyc_pll_disable(usbphyc);
306 		if (ret)
307 			goto dec_n_pll_cons;
308 	}
309 
310 	ret = stm32_usbphyc_regulators_enable(usbphyc);
311 	if (ret)
312 		goto dec_n_pll_cons;
313 
314 	ret = stm32_usbphyc_pll_init(usbphyc);
315 	if (ret)
316 		goto reg_disable;
317 
318 	stm32_usbphyc_set_bits(pll_reg, PLLEN);
319 
320 	return 0;
321 
322 reg_disable:
323 	stm32_usbphyc_regulators_disable(usbphyc);
324 
325 dec_n_pll_cons:
326 	atomic_dec(&usbphyc->n_pll_cons);
327 
328 	return ret;
329 }
330 
331 static int stm32_usbphyc_phy_init(struct phy *phy)
332 {
333 	struct stm32_usbphyc_phy *usbphyc_phy = phy_get_drvdata(phy);
334 	struct stm32_usbphyc *usbphyc = usbphyc_phy->usbphyc;
335 	u32 reg_mon = STM32_USBPHYC_MONITOR(usbphyc_phy->index);
336 	u32 monsel = FIELD_PREP(STM32_USBPHYC_MON_SEL,
337 				STM32_USBPHYC_MON_SEL_LOCKP);
338 	u32 monout;
339 	int ret;
340 
341 	ret = stm32_usbphyc_pll_enable(usbphyc);
342 	if (ret)
343 		return ret;
344 
345 	/* Check that PLL Lock input to PHY is High */
346 	writel_relaxed(monsel, usbphyc->base + reg_mon);
347 	ret = readl_relaxed_poll_timeout(usbphyc->base + reg_mon, monout,
348 					 (monout & STM32_USBPHYC_MON_OUT_LOCKP),
349 					 100, 1000);
350 	if (ret) {
351 		dev_err(usbphyc->dev, "PLL Lock input to PHY is Low (val=%x)\n",
352 			(u32)(monout & STM32_USBPHYC_MON_OUT));
353 		goto pll_disable;
354 	}
355 
356 	usbphyc_phy->active = true;
357 
358 	return 0;
359 
360 pll_disable:
361 	return stm32_usbphyc_pll_disable(usbphyc);
362 }
363 
364 static int stm32_usbphyc_phy_exit(struct phy *phy)
365 {
366 	struct stm32_usbphyc_phy *usbphyc_phy = phy_get_drvdata(phy);
367 	struct stm32_usbphyc *usbphyc = usbphyc_phy->usbphyc;
368 
369 	usbphyc_phy->active = false;
370 
371 	return stm32_usbphyc_pll_disable(usbphyc);
372 }
373 
374 static int stm32_usbphyc_phy_power_on(struct phy *phy)
375 {
376 	struct stm32_usbphyc_phy *usbphyc_phy = phy_get_drvdata(phy);
377 
378 	if (usbphyc_phy->vbus)
379 		return regulator_enable(usbphyc_phy->vbus);
380 
381 	return 0;
382 }
383 
384 static int stm32_usbphyc_phy_power_off(struct phy *phy)
385 {
386 	struct stm32_usbphyc_phy *usbphyc_phy = phy_get_drvdata(phy);
387 
388 	if (usbphyc_phy->vbus)
389 		return regulator_disable(usbphyc_phy->vbus);
390 
391 	return 0;
392 }
393 
394 static const struct phy_ops stm32_usbphyc_phy_ops = {
395 	.init = stm32_usbphyc_phy_init,
396 	.exit = stm32_usbphyc_phy_exit,
397 	.power_on = stm32_usbphyc_phy_power_on,
398 	.power_off = stm32_usbphyc_phy_power_off,
399 	.owner = THIS_MODULE,
400 };
401 
402 static int stm32_usbphyc_clk48_prepare(struct clk_hw *hw)
403 {
404 	struct stm32_usbphyc *usbphyc = container_of(hw, struct stm32_usbphyc, clk48_hw);
405 
406 	return stm32_usbphyc_pll_enable(usbphyc);
407 }
408 
409 static void stm32_usbphyc_clk48_unprepare(struct clk_hw *hw)
410 {
411 	struct stm32_usbphyc *usbphyc = container_of(hw, struct stm32_usbphyc, clk48_hw);
412 
413 	stm32_usbphyc_pll_disable(usbphyc);
414 }
415 
416 static unsigned long stm32_usbphyc_clk48_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
417 {
418 	return 48000000;
419 }
420 
421 static const struct clk_ops usbphyc_clk48_ops = {
422 	.prepare = stm32_usbphyc_clk48_prepare,
423 	.unprepare = stm32_usbphyc_clk48_unprepare,
424 	.recalc_rate = stm32_usbphyc_clk48_recalc_rate,
425 };
426 
427 static void stm32_usbphyc_clk48_unregister(void *data)
428 {
429 	struct stm32_usbphyc *usbphyc = data;
430 
431 	of_clk_del_provider(usbphyc->dev->of_node);
432 	clk_hw_unregister(&usbphyc->clk48_hw);
433 }
434 
435 static int stm32_usbphyc_clk48_register(struct stm32_usbphyc *usbphyc)
436 {
437 	struct device_node *node = usbphyc->dev->of_node;
438 	struct clk_init_data init = { };
439 	int ret = 0;
440 
441 	init.name = "ck_usbo_48m";
442 	init.ops = &usbphyc_clk48_ops;
443 
444 	usbphyc->clk48_hw.init = &init;
445 
446 	ret = clk_hw_register(usbphyc->dev, &usbphyc->clk48_hw);
447 	if (ret)
448 		return ret;
449 
450 	ret = of_clk_add_hw_provider(node, of_clk_hw_simple_get, &usbphyc->clk48_hw);
451 	if (ret)
452 		clk_hw_unregister(&usbphyc->clk48_hw);
453 
454 	return ret;
455 }
456 
457 static void stm32_usbphyc_phy_tuning(struct stm32_usbphyc *usbphyc,
458 				     struct device_node *np, u32 index)
459 {
460 	struct stm32_usbphyc_phy *usbphyc_phy = usbphyc->phys[index];
461 	u32 reg = STM32_USBPHYC_TUNE(index);
462 	u32 otpcomp, val;
463 	int ret;
464 
465 	/* Backup OTP compensation code */
466 	otpcomp = FIELD_GET(OTPCOMP, readl_relaxed(usbphyc->base + reg));
467 
468 	ret = of_property_read_u32(np, "st,current-boost-microamp", &val);
469 	if (ret != -EINVAL) {
470 		if (!ret && (val == BOOST_1000_UA || val == BOOST_2000_UA)) {
471 			val = (val == BOOST_2000_UA) ? 1 : 0;
472 			usbphyc_phy->tune |= INCURREN | FIELD_PREP(INCURRINT, val);
473 		} else {
474 			dev_warn(usbphyc->dev, "phy%d: invalid st,current-boost-microamp\n", index);
475 		}
476 	}
477 
478 	if (!of_property_read_bool(np, "st,no-lsfs-fb-cap"))
479 		usbphyc_phy->tune |= LFSCAPEN;
480 
481 	if (of_property_read_bool(np, "st,decrease-hs-slew-rate"))
482 		usbphyc_phy->tune |= HSDRVSLEW;
483 
484 	ret = of_property_read_u32(np, "st,tune-hs-dc-level", &val);
485 	if (ret != -EINVAL) {
486 		if (!ret && val < DC_MAX) {
487 			if (val == DC_MINUS_5_TO_7_MV) {/* Decreases HS driver DC level */
488 				usbphyc_phy->tune |= HSDRVDCCUR;
489 			} else if (val > 0) {		/* Increases HS driver DC level */
490 				val = (val == DC_PLUS_10_TO_14_MV) ? 1 : 0;
491 				usbphyc_phy->tune |= HSDRVCURINCR | FIELD_PREP(HSDRVDCLEV, val);
492 			}
493 		} else {
494 			dev_warn(usbphyc->dev, "phy%d: invalid st,tune-hs-dc-level\n", index);
495 		}
496 	}
497 
498 	if (of_property_read_bool(np, "st,enable-fs-rftime-tuning"))
499 		usbphyc_phy->tune |= FSDRVRFADJ;
500 
501 	if (of_property_read_bool(np, "st,enable-hs-rftime-reduction"))
502 		usbphyc_phy->tune |= HSDRVRFRED;
503 
504 	ret = of_property_read_u32(np, "st,trim-hs-current", &val);
505 	if (ret != -EINVAL) {
506 		if (!ret && val < CUR_MAX)
507 			usbphyc_phy->tune |= FIELD_PREP(HSDRVCHKITRM, val);
508 		else
509 			dev_warn(usbphyc->dev, "phy%d: invalid st,trim-hs-current\n", index);
510 	}
511 
512 	ret = of_property_read_u32(np, "st,trim-hs-impedance", &val);
513 	if (ret != -EINVAL) {
514 		if (!ret && val < IMP_MAX)
515 			usbphyc_phy->tune |= FIELD_PREP(HSDRVCHKZTRM, val);
516 		else
517 			dev_warn(usbphyc->dev, "phy%d: invalid st,trim-hs-impedance\n", index);
518 	}
519 
520 	ret = of_property_read_u32(np, "st,tune-squelch-level", &val);
521 	if (ret != -EINVAL) {
522 		if (!ret && val < SQLCH_MAX)
523 			usbphyc_phy->tune |= FIELD_PREP(SQLCHCTL, val);
524 		else
525 			dev_warn(usbphyc->dev, "phy%d: invalid st,tune-squelch\n", index);
526 	}
527 
528 	if (of_property_read_bool(np, "st,enable-hs-rx-gain-eq"))
529 		usbphyc_phy->tune |= HDRXGNEQEN;
530 
531 	ret = of_property_read_u32(np, "st,tune-hs-rx-offset", &val);
532 	if (ret != -EINVAL) {
533 		if (!ret && val < RX_OFFSET_MAX)
534 			usbphyc_phy->tune |= FIELD_PREP(HSRXOFF, val);
535 		else
536 			dev_warn(usbphyc->dev, "phy%d: invalid st,tune-hs-rx-offset\n", index);
537 	}
538 
539 	if (of_property_read_bool(np, "st,no-hs-ftime-ctrl"))
540 		usbphyc_phy->tune |= HSFALLPREEM;
541 
542 	if (!of_property_read_bool(np, "st,no-lsfs-sc"))
543 		usbphyc_phy->tune |= SHTCCTCTLPROT;
544 
545 	if (of_property_read_bool(np, "st,enable-hs-tx-staggering"))
546 		usbphyc_phy->tune |= STAGSEL;
547 
548 	/* Restore OTP compensation code */
549 	usbphyc_phy->tune |= FIELD_PREP(OTPCOMP, otpcomp);
550 
551 	/*
552 	 * By default, if no st,xxx tuning property is used, usbphyc_phy->tune is equal to
553 	 * STM32_USBPHYC_TUNE reset value (LFSCAPEN | SHTCCTCTLPROT | OTPCOMP).
554 	 */
555 	writel_relaxed(usbphyc_phy->tune, usbphyc->base + reg);
556 }
557 
558 static void stm32_usbphyc_switch_setup(struct stm32_usbphyc *usbphyc,
559 				       u32 utmi_switch)
560 {
561 	if (!utmi_switch)
562 		stm32_usbphyc_clr_bits(usbphyc->base + STM32_USBPHYC_MISC,
563 				       SWITHOST);
564 	else
565 		stm32_usbphyc_set_bits(usbphyc->base + STM32_USBPHYC_MISC,
566 				       SWITHOST);
567 	usbphyc->switch_setup = utmi_switch;
568 }
569 
570 static struct phy *stm32_usbphyc_of_xlate(struct device *dev,
571 					  struct of_phandle_args *args)
572 {
573 	struct stm32_usbphyc *usbphyc = dev_get_drvdata(dev);
574 	struct stm32_usbphyc_phy *usbphyc_phy = NULL;
575 	struct device_node *phynode = args->np;
576 	int port = 0;
577 
578 	for (port = 0; port < usbphyc->nphys; port++) {
579 		if (phynode == usbphyc->phys[port]->phy->dev.of_node) {
580 			usbphyc_phy = usbphyc->phys[port];
581 			break;
582 		}
583 	}
584 	if (!usbphyc_phy) {
585 		dev_err(dev, "failed to find phy\n");
586 		return ERR_PTR(-EINVAL);
587 	}
588 
589 	if (((usbphyc_phy->index == 0) && (args->args_count != 0)) ||
590 	    ((usbphyc_phy->index == 1) && (args->args_count != 1))) {
591 		dev_err(dev, "invalid number of cells for phy port%d\n",
592 			usbphyc_phy->index);
593 		return ERR_PTR(-EINVAL);
594 	}
595 
596 	/* Configure the UTMI switch for PHY port#2 */
597 	if (usbphyc_phy->index == 1) {
598 		if (usbphyc->switch_setup < 0) {
599 			stm32_usbphyc_switch_setup(usbphyc, args->args[0]);
600 		} else {
601 			if (args->args[0] != usbphyc->switch_setup) {
602 				dev_err(dev, "phy port1 already used\n");
603 				return ERR_PTR(-EBUSY);
604 			}
605 		}
606 	}
607 
608 	return usbphyc_phy->phy;
609 }
610 
611 static int stm32_usbphyc_probe(struct platform_device *pdev)
612 {
613 	struct stm32_usbphyc *usbphyc;
614 	struct device *dev = &pdev->dev;
615 	struct device_node *child, *np = dev->of_node;
616 	struct phy_provider *phy_provider;
617 	u32 pllen, version;
618 	int ret, port = 0;
619 
620 	usbphyc = devm_kzalloc(dev, sizeof(*usbphyc), GFP_KERNEL);
621 	if (!usbphyc)
622 		return -ENOMEM;
623 	usbphyc->dev = dev;
624 	dev_set_drvdata(dev, usbphyc);
625 
626 	usbphyc->base = devm_platform_ioremap_resource(pdev, 0);
627 	if (IS_ERR(usbphyc->base))
628 		return PTR_ERR(usbphyc->base);
629 
630 	usbphyc->clk = devm_clk_get(dev, NULL);
631 	if (IS_ERR(usbphyc->clk))
632 		return dev_err_probe(dev, PTR_ERR(usbphyc->clk), "clk get_failed\n");
633 
634 	ret = clk_prepare_enable(usbphyc->clk);
635 	if (ret) {
636 		dev_err(dev, "clk enable failed: %d\n", ret);
637 		return ret;
638 	}
639 
640 	usbphyc->rst = devm_reset_control_get(dev, NULL);
641 	if (!IS_ERR(usbphyc->rst)) {
642 		reset_control_assert(usbphyc->rst);
643 		udelay(2);
644 		reset_control_deassert(usbphyc->rst);
645 	} else {
646 		ret = PTR_ERR(usbphyc->rst);
647 		if (ret == -EPROBE_DEFER)
648 			goto clk_disable;
649 
650 		stm32_usbphyc_clr_bits(usbphyc->base + STM32_USBPHYC_PLL, PLLEN);
651 	}
652 
653 	/*
654 	 * Wait for minimum width of powerdown pulse (ENABLE = Low):
655 	 * we have to ensure the PLL is disabled before phys initialization.
656 	 */
657 	if (readl_relaxed_poll_timeout(usbphyc->base + STM32_USBPHYC_PLL,
658 				       pllen, !(pllen & PLLEN), 5, 50)) {
659 		dev_warn(usbphyc->dev, "PLL not reset\n");
660 		ret = -EPROBE_DEFER;
661 		goto clk_disable;
662 	}
663 
664 	usbphyc->switch_setup = -EINVAL;
665 	usbphyc->nphys = of_get_child_count(np);
666 	usbphyc->phys = devm_kcalloc(dev, usbphyc->nphys,
667 				     sizeof(*usbphyc->phys), GFP_KERNEL);
668 	if (!usbphyc->phys) {
669 		ret = -ENOMEM;
670 		goto clk_disable;
671 	}
672 
673 	usbphyc->vdda1v1 = devm_regulator_get(dev, "vdda1v1");
674 	if (IS_ERR(usbphyc->vdda1v1)) {
675 		ret = dev_err_probe(dev, PTR_ERR(usbphyc->vdda1v1),
676 				    "failed to get vdda1v1 supply\n");
677 		goto clk_disable;
678 	}
679 
680 	usbphyc->vdda1v8 = devm_regulator_get(dev, "vdda1v8");
681 	if (IS_ERR(usbphyc->vdda1v8)) {
682 		ret = dev_err_probe(dev, PTR_ERR(usbphyc->vdda1v8),
683 				    "failed to get vdda1v8 supply\n");
684 		goto clk_disable;
685 	}
686 
687 	for_each_child_of_node(np, child) {
688 		struct stm32_usbphyc_phy *usbphyc_phy;
689 		struct phy *phy;
690 		u32 index;
691 
692 		phy = devm_phy_create(dev, child, &stm32_usbphyc_phy_ops);
693 		if (IS_ERR(phy)) {
694 			ret = PTR_ERR(phy);
695 			if (ret != -EPROBE_DEFER)
696 				dev_err(dev, "failed to create phy%d: %d\n",
697 					port, ret);
698 			goto put_child;
699 		}
700 
701 		usbphyc_phy = devm_kzalloc(dev, sizeof(*usbphyc_phy),
702 					   GFP_KERNEL);
703 		if (!usbphyc_phy) {
704 			ret = -ENOMEM;
705 			goto put_child;
706 		}
707 
708 		ret = of_property_read_u32(child, "reg", &index);
709 		if (ret || index > usbphyc->nphys) {
710 			dev_err(&phy->dev, "invalid reg property: %d\n", ret);
711 			goto put_child;
712 		}
713 
714 		usbphyc->phys[port] = usbphyc_phy;
715 		phy_set_bus_width(phy, 8);
716 		phy_set_drvdata(phy, usbphyc_phy);
717 
718 		usbphyc->phys[port]->phy = phy;
719 		usbphyc->phys[port]->usbphyc = usbphyc;
720 		usbphyc->phys[port]->index = index;
721 		usbphyc->phys[port]->active = false;
722 
723 		usbphyc->phys[port]->vbus = devm_regulator_get_optional(&phy->dev, "vbus");
724 		if (IS_ERR(usbphyc->phys[port]->vbus)) {
725 			ret = PTR_ERR(usbphyc->phys[port]->vbus);
726 			if (ret == -EPROBE_DEFER)
727 				goto put_child;
728 			usbphyc->phys[port]->vbus = NULL;
729 		}
730 
731 		/* Configure phy tuning */
732 		stm32_usbphyc_phy_tuning(usbphyc, child, index);
733 
734 		port++;
735 	}
736 
737 	phy_provider = devm_of_phy_provider_register(dev,
738 						     stm32_usbphyc_of_xlate);
739 	if (IS_ERR(phy_provider)) {
740 		ret = PTR_ERR(phy_provider);
741 		dev_err(dev, "failed to register phy provider: %d\n", ret);
742 		goto clk_disable;
743 	}
744 
745 	ret = stm32_usbphyc_clk48_register(usbphyc);
746 	if (ret) {
747 		dev_err(dev, "failed to register ck_usbo_48m clock: %d\n", ret);
748 		goto clk_disable;
749 	}
750 
751 	version = readl_relaxed(usbphyc->base + STM32_USBPHYC_VERSION);
752 	dev_info(dev, "registered rev:%lu.%lu\n",
753 		 FIELD_GET(MAJREV, version), FIELD_GET(MINREV, version));
754 
755 	return 0;
756 
757 put_child:
758 	of_node_put(child);
759 clk_disable:
760 	clk_disable_unprepare(usbphyc->clk);
761 
762 	return ret;
763 }
764 
765 static int stm32_usbphyc_remove(struct platform_device *pdev)
766 {
767 	struct stm32_usbphyc *usbphyc = dev_get_drvdata(&pdev->dev);
768 	int port;
769 
770 	/* Ensure PHYs are not active, to allow PLL disabling */
771 	for (port = 0; port < usbphyc->nphys; port++)
772 		if (usbphyc->phys[port]->active)
773 			stm32_usbphyc_phy_exit(usbphyc->phys[port]->phy);
774 
775 	stm32_usbphyc_clk48_unregister(usbphyc);
776 
777 	clk_disable_unprepare(usbphyc->clk);
778 
779 	return 0;
780 }
781 
782 static int __maybe_unused stm32_usbphyc_resume(struct device *dev)
783 {
784 	struct stm32_usbphyc *usbphyc = dev_get_drvdata(dev);
785 	struct stm32_usbphyc_phy *usbphyc_phy;
786 	int port;
787 
788 	if (usbphyc->switch_setup >= 0)
789 		stm32_usbphyc_switch_setup(usbphyc, usbphyc->switch_setup);
790 
791 	for (port = 0; port < usbphyc->nphys; port++) {
792 		usbphyc_phy = usbphyc->phys[port];
793 		writel_relaxed(usbphyc_phy->tune, usbphyc->base + STM32_USBPHYC_TUNE(port));
794 	}
795 
796 	return 0;
797 }
798 
799 static SIMPLE_DEV_PM_OPS(stm32_usbphyc_pm_ops, NULL, stm32_usbphyc_resume);
800 
801 static const struct of_device_id stm32_usbphyc_of_match[] = {
802 	{ .compatible = "st,stm32mp1-usbphyc", },
803 	{ },
804 };
805 MODULE_DEVICE_TABLE(of, stm32_usbphyc_of_match);
806 
807 static struct platform_driver stm32_usbphyc_driver = {
808 	.probe = stm32_usbphyc_probe,
809 	.remove = stm32_usbphyc_remove,
810 	.driver = {
811 		.of_match_table = stm32_usbphyc_of_match,
812 		.name = "stm32-usbphyc",
813 		.pm = &stm32_usbphyc_pm_ops,
814 	}
815 };
816 module_platform_driver(stm32_usbphyc_driver);
817 
818 MODULE_DESCRIPTION("STMicroelectronics STM32 USBPHYC driver");
819 MODULE_AUTHOR("Amelie Delaunay <amelie.delaunay@st.com>");
820 MODULE_LICENSE("GPL v2");
821