xref: /openbmc/linux/drivers/iio/adc/stm32-adc-core.c (revision 6cc23ed2)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * This file is part of STM32 ADC driver
4  *
5  * Copyright (C) 2016, STMicroelectronics - All Rights Reserved
6  * Author: Fabrice Gasnier <fabrice.gasnier@st.com>.
7  *
8  * Inspired from: fsl-imx25-tsadc
9  *
10  */
11 
12 #include <linux/clk.h>
13 #include <linux/interrupt.h>
14 #include <linux/irqchip/chained_irq.h>
15 #include <linux/irqdesc.h>
16 #include <linux/irqdomain.h>
17 #include <linux/mfd/syscon.h>
18 #include <linux/module.h>
19 #include <linux/of_device.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/regmap.h>
22 #include <linux/regulator/consumer.h>
23 #include <linux/slab.h>
24 
25 #include "stm32-adc-core.h"
26 
27 /* STM32F4 - common registers for all ADC instances: 1, 2 & 3 */
28 #define STM32F4_ADC_CSR			(STM32_ADCX_COMN_OFFSET + 0x00)
29 #define STM32F4_ADC_CCR			(STM32_ADCX_COMN_OFFSET + 0x04)
30 
31 /* STM32F4_ADC_CSR - bit fields */
32 #define STM32F4_EOC3			BIT(17)
33 #define STM32F4_EOC2			BIT(9)
34 #define STM32F4_EOC1			BIT(1)
35 
36 /* STM32F4_ADC_CCR - bit fields */
37 #define STM32F4_ADC_ADCPRE_SHIFT	16
38 #define STM32F4_ADC_ADCPRE_MASK		GENMASK(17, 16)
39 
40 /* STM32H7 - common registers for all ADC instances */
41 #define STM32H7_ADC_CSR			(STM32_ADCX_COMN_OFFSET + 0x00)
42 #define STM32H7_ADC_CCR			(STM32_ADCX_COMN_OFFSET + 0x08)
43 
44 /* STM32H7_ADC_CSR - bit fields */
45 #define STM32H7_EOC_SLV			BIT(18)
46 #define STM32H7_EOC_MST			BIT(2)
47 
48 /* STM32H7_ADC_CCR - bit fields */
49 #define STM32H7_PRESC_SHIFT		18
50 #define STM32H7_PRESC_MASK		GENMASK(21, 18)
51 #define STM32H7_CKMODE_SHIFT		16
52 #define STM32H7_CKMODE_MASK		GENMASK(17, 16)
53 
54 #define STM32_ADC_CORE_SLEEP_DELAY_MS	2000
55 
56 /* SYSCFG registers */
57 #define STM32MP1_SYSCFG_PMCSETR		0x04
58 #define STM32MP1_SYSCFG_PMCCLRR		0x44
59 
60 /* SYSCFG bit fields */
61 #define STM32MP1_SYSCFG_ANASWVDD_MASK	BIT(9)
62 
63 /* SYSCFG capability flags */
64 #define HAS_VBOOSTER		BIT(0)
65 #define HAS_ANASWVDD		BIT(1)
66 
67 /**
68  * stm32_adc_common_regs - stm32 common registers, compatible dependent data
69  * @csr:	common status register offset
70  * @ccr:	common control register offset
71  * @eoc1:	adc1 end of conversion flag in @csr
72  * @eoc2:	adc2 end of conversion flag in @csr
73  * @eoc3:	adc3 end of conversion flag in @csr
74  */
75 struct stm32_adc_common_regs {
76 	u32 csr;
77 	u32 ccr;
78 	u32 eoc1_msk;
79 	u32 eoc2_msk;
80 	u32 eoc3_msk;
81 };
82 
83 struct stm32_adc_priv;
84 
85 /**
86  * stm32_adc_priv_cfg - stm32 core compatible configuration data
87  * @regs:	common registers for all instances
88  * @clk_sel:	clock selection routine
89  * @max_clk_rate_hz: maximum analog clock rate (Hz, from datasheet)
90  * @has_syscfg: SYSCFG capability flags
91  */
92 struct stm32_adc_priv_cfg {
93 	const struct stm32_adc_common_regs *regs;
94 	int (*clk_sel)(struct platform_device *, struct stm32_adc_priv *);
95 	u32 max_clk_rate_hz;
96 	unsigned int has_syscfg;
97 };
98 
99 /**
100  * struct stm32_adc_priv - stm32 ADC core private data
101  * @irq:		irq(s) for ADC block
102  * @domain:		irq domain reference
103  * @aclk:		clock reference for the analog circuitry
104  * @bclk:		bus clock common for all ADCs, depends on part used
105  * @booster:		booster supply reference
106  * @vdd:		vdd supply reference
107  * @vdda:		vdda analog supply reference
108  * @vref:		regulator reference
109  * @vdd_uv:		vdd supply voltage (microvolts)
110  * @vdda_uv:		vdda supply voltage (microvolts)
111  * @cfg:		compatible configuration data
112  * @common:		common data for all ADC instances
113  * @ccr_bak:		backup CCR in low power mode
114  * @syscfg:		reference to syscon, system control registers
115  */
116 struct stm32_adc_priv {
117 	int				irq[STM32_ADC_MAX_ADCS];
118 	struct irq_domain		*domain;
119 	struct clk			*aclk;
120 	struct clk			*bclk;
121 	struct regulator		*booster;
122 	struct regulator		*vdd;
123 	struct regulator		*vdda;
124 	struct regulator		*vref;
125 	int				vdd_uv;
126 	int				vdda_uv;
127 	const struct stm32_adc_priv_cfg	*cfg;
128 	struct stm32_adc_common		common;
129 	u32				ccr_bak;
130 	struct regmap			*syscfg;
131 };
132 
133 static struct stm32_adc_priv *to_stm32_adc_priv(struct stm32_adc_common *com)
134 {
135 	return container_of(com, struct stm32_adc_priv, common);
136 }
137 
138 /* STM32F4 ADC internal common clock prescaler division ratios */
139 static int stm32f4_pclk_div[] = {2, 4, 6, 8};
140 
141 /**
142  * stm32f4_adc_clk_sel() - Select stm32f4 ADC common clock prescaler
143  * @priv: stm32 ADC core private data
144  * Select clock prescaler used for analog conversions, before using ADC.
145  */
146 static int stm32f4_adc_clk_sel(struct platform_device *pdev,
147 			       struct stm32_adc_priv *priv)
148 {
149 	unsigned long rate;
150 	u32 val;
151 	int i;
152 
153 	/* stm32f4 has one clk input for analog (mandatory), enforce it here */
154 	if (!priv->aclk) {
155 		dev_err(&pdev->dev, "No 'adc' clock found\n");
156 		return -ENOENT;
157 	}
158 
159 	rate = clk_get_rate(priv->aclk);
160 	if (!rate) {
161 		dev_err(&pdev->dev, "Invalid clock rate: 0\n");
162 		return -EINVAL;
163 	}
164 
165 	for (i = 0; i < ARRAY_SIZE(stm32f4_pclk_div); i++) {
166 		if ((rate / stm32f4_pclk_div[i]) <= priv->cfg->max_clk_rate_hz)
167 			break;
168 	}
169 	if (i >= ARRAY_SIZE(stm32f4_pclk_div)) {
170 		dev_err(&pdev->dev, "adc clk selection failed\n");
171 		return -EINVAL;
172 	}
173 
174 	priv->common.rate = rate / stm32f4_pclk_div[i];
175 	val = readl_relaxed(priv->common.base + STM32F4_ADC_CCR);
176 	val &= ~STM32F4_ADC_ADCPRE_MASK;
177 	val |= i << STM32F4_ADC_ADCPRE_SHIFT;
178 	writel_relaxed(val, priv->common.base + STM32F4_ADC_CCR);
179 
180 	dev_dbg(&pdev->dev, "Using analog clock source at %ld kHz\n",
181 		priv->common.rate / 1000);
182 
183 	return 0;
184 }
185 
186 /**
187  * struct stm32h7_adc_ck_spec - specification for stm32h7 adc clock
188  * @ckmode: ADC clock mode, Async or sync with prescaler.
189  * @presc: prescaler bitfield for async clock mode
190  * @div: prescaler division ratio
191  */
192 struct stm32h7_adc_ck_spec {
193 	u32 ckmode;
194 	u32 presc;
195 	int div;
196 };
197 
198 static const struct stm32h7_adc_ck_spec stm32h7_adc_ckmodes_spec[] = {
199 	/* 00: CK_ADC[1..3]: Asynchronous clock modes */
200 	{ 0, 0, 1 },
201 	{ 0, 1, 2 },
202 	{ 0, 2, 4 },
203 	{ 0, 3, 6 },
204 	{ 0, 4, 8 },
205 	{ 0, 5, 10 },
206 	{ 0, 6, 12 },
207 	{ 0, 7, 16 },
208 	{ 0, 8, 32 },
209 	{ 0, 9, 64 },
210 	{ 0, 10, 128 },
211 	{ 0, 11, 256 },
212 	/* HCLK used: Synchronous clock modes (1, 2 or 4 prescaler) */
213 	{ 1, 0, 1 },
214 	{ 2, 0, 2 },
215 	{ 3, 0, 4 },
216 };
217 
218 static int stm32h7_adc_clk_sel(struct platform_device *pdev,
219 			       struct stm32_adc_priv *priv)
220 {
221 	u32 ckmode, presc, val;
222 	unsigned long rate;
223 	int i, div;
224 
225 	/* stm32h7 bus clock is common for all ADC instances (mandatory) */
226 	if (!priv->bclk) {
227 		dev_err(&pdev->dev, "No 'bus' clock found\n");
228 		return -ENOENT;
229 	}
230 
231 	/*
232 	 * stm32h7 can use either 'bus' or 'adc' clock for analog circuitry.
233 	 * So, choice is to have bus clock mandatory and adc clock optional.
234 	 * If optional 'adc' clock has been found, then try to use it first.
235 	 */
236 	if (priv->aclk) {
237 		/*
238 		 * Asynchronous clock modes (e.g. ckmode == 0)
239 		 * From spec: PLL output musn't exceed max rate
240 		 */
241 		rate = clk_get_rate(priv->aclk);
242 		if (!rate) {
243 			dev_err(&pdev->dev, "Invalid adc clock rate: 0\n");
244 			return -EINVAL;
245 		}
246 
247 		for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
248 			ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
249 			presc = stm32h7_adc_ckmodes_spec[i].presc;
250 			div = stm32h7_adc_ckmodes_spec[i].div;
251 
252 			if (ckmode)
253 				continue;
254 
255 			if ((rate / div) <= priv->cfg->max_clk_rate_hz)
256 				goto out;
257 		}
258 	}
259 
260 	/* Synchronous clock modes (e.g. ckmode is 1, 2 or 3) */
261 	rate = clk_get_rate(priv->bclk);
262 	if (!rate) {
263 		dev_err(&pdev->dev, "Invalid bus clock rate: 0\n");
264 		return -EINVAL;
265 	}
266 
267 	for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
268 		ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
269 		presc = stm32h7_adc_ckmodes_spec[i].presc;
270 		div = stm32h7_adc_ckmodes_spec[i].div;
271 
272 		if (!ckmode)
273 			continue;
274 
275 		if ((rate / div) <= priv->cfg->max_clk_rate_hz)
276 			goto out;
277 	}
278 
279 	dev_err(&pdev->dev, "adc clk selection failed\n");
280 	return -EINVAL;
281 
282 out:
283 	/* rate used later by each ADC instance to control BOOST mode */
284 	priv->common.rate = rate / div;
285 
286 	/* Set common clock mode and prescaler */
287 	val = readl_relaxed(priv->common.base + STM32H7_ADC_CCR);
288 	val &= ~(STM32H7_CKMODE_MASK | STM32H7_PRESC_MASK);
289 	val |= ckmode << STM32H7_CKMODE_SHIFT;
290 	val |= presc << STM32H7_PRESC_SHIFT;
291 	writel_relaxed(val, priv->common.base + STM32H7_ADC_CCR);
292 
293 	dev_dbg(&pdev->dev, "Using %s clock/%d source at %ld kHz\n",
294 		ckmode ? "bus" : "adc", div, priv->common.rate / 1000);
295 
296 	return 0;
297 }
298 
299 /* STM32F4 common registers definitions */
300 static const struct stm32_adc_common_regs stm32f4_adc_common_regs = {
301 	.csr = STM32F4_ADC_CSR,
302 	.ccr = STM32F4_ADC_CCR,
303 	.eoc1_msk = STM32F4_EOC1,
304 	.eoc2_msk = STM32F4_EOC2,
305 	.eoc3_msk = STM32F4_EOC3,
306 };
307 
308 /* STM32H7 common registers definitions */
309 static const struct stm32_adc_common_regs stm32h7_adc_common_regs = {
310 	.csr = STM32H7_ADC_CSR,
311 	.ccr = STM32H7_ADC_CCR,
312 	.eoc1_msk = STM32H7_EOC_MST,
313 	.eoc2_msk = STM32H7_EOC_SLV,
314 };
315 
316 /* ADC common interrupt for all instances */
317 static void stm32_adc_irq_handler(struct irq_desc *desc)
318 {
319 	struct stm32_adc_priv *priv = irq_desc_get_handler_data(desc);
320 	struct irq_chip *chip = irq_desc_get_chip(desc);
321 	u32 status;
322 
323 	chained_irq_enter(chip, desc);
324 	status = readl_relaxed(priv->common.base + priv->cfg->regs->csr);
325 
326 	if (status & priv->cfg->regs->eoc1_msk)
327 		generic_handle_irq(irq_find_mapping(priv->domain, 0));
328 
329 	if (status & priv->cfg->regs->eoc2_msk)
330 		generic_handle_irq(irq_find_mapping(priv->domain, 1));
331 
332 	if (status & priv->cfg->regs->eoc3_msk)
333 		generic_handle_irq(irq_find_mapping(priv->domain, 2));
334 
335 	chained_irq_exit(chip, desc);
336 };
337 
338 static int stm32_adc_domain_map(struct irq_domain *d, unsigned int irq,
339 				irq_hw_number_t hwirq)
340 {
341 	irq_set_chip_data(irq, d->host_data);
342 	irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_level_irq);
343 
344 	return 0;
345 }
346 
347 static void stm32_adc_domain_unmap(struct irq_domain *d, unsigned int irq)
348 {
349 	irq_set_chip_and_handler(irq, NULL, NULL);
350 	irq_set_chip_data(irq, NULL);
351 }
352 
353 static const struct irq_domain_ops stm32_adc_domain_ops = {
354 	.map = stm32_adc_domain_map,
355 	.unmap  = stm32_adc_domain_unmap,
356 	.xlate = irq_domain_xlate_onecell,
357 };
358 
359 static int stm32_adc_irq_probe(struct platform_device *pdev,
360 			       struct stm32_adc_priv *priv)
361 {
362 	struct device_node *np = pdev->dev.of_node;
363 	unsigned int i;
364 
365 	for (i = 0; i < STM32_ADC_MAX_ADCS; i++) {
366 		priv->irq[i] = platform_get_irq(pdev, i);
367 		if (priv->irq[i] < 0) {
368 			/*
369 			 * At least one interrupt must be provided, make others
370 			 * optional:
371 			 * - stm32f4/h7 shares a common interrupt.
372 			 * - stm32mp1, has one line per ADC (either for ADC1,
373 			 *   ADC2 or both).
374 			 */
375 			if (i && priv->irq[i] == -ENXIO)
376 				continue;
377 
378 			return priv->irq[i];
379 		}
380 	}
381 
382 	priv->domain = irq_domain_add_simple(np, STM32_ADC_MAX_ADCS, 0,
383 					     &stm32_adc_domain_ops,
384 					     priv);
385 	if (!priv->domain) {
386 		dev_err(&pdev->dev, "Failed to add irq domain\n");
387 		return -ENOMEM;
388 	}
389 
390 	for (i = 0; i < STM32_ADC_MAX_ADCS; i++) {
391 		if (priv->irq[i] < 0)
392 			continue;
393 		irq_set_chained_handler(priv->irq[i], stm32_adc_irq_handler);
394 		irq_set_handler_data(priv->irq[i], priv);
395 	}
396 
397 	return 0;
398 }
399 
400 static void stm32_adc_irq_remove(struct platform_device *pdev,
401 				 struct stm32_adc_priv *priv)
402 {
403 	int hwirq;
404 	unsigned int i;
405 
406 	for (hwirq = 0; hwirq < STM32_ADC_MAX_ADCS; hwirq++)
407 		irq_dispose_mapping(irq_find_mapping(priv->domain, hwirq));
408 	irq_domain_remove(priv->domain);
409 
410 	for (i = 0; i < STM32_ADC_MAX_ADCS; i++) {
411 		if (priv->irq[i] < 0)
412 			continue;
413 		irq_set_chained_handler(priv->irq[i], NULL);
414 	}
415 }
416 
417 static int stm32_adc_core_switches_supply_en(struct stm32_adc_priv *priv,
418 					     struct device *dev)
419 {
420 	int ret;
421 
422 	/*
423 	 * On STM32H7 and STM32MP1, the ADC inputs are multiplexed with analog
424 	 * switches (via PCSEL) which have reduced performances when their
425 	 * supply is below 2.7V (vdda by default):
426 	 * - Voltage booster can be used, to get full ADC performances
427 	 *   (increases power consumption).
428 	 * - Vdd can be used to supply them, if above 2.7V (STM32MP1 only).
429 	 *
430 	 * Recommended settings for ANASWVDD and EN_BOOSTER:
431 	 * - vdda < 2.7V but vdd > 2.7V: ANASWVDD = 1, EN_BOOSTER = 0 (stm32mp1)
432 	 * - vdda < 2.7V and vdd < 2.7V: ANASWVDD = 0, EN_BOOSTER = 1
433 	 * - vdda >= 2.7V:               ANASWVDD = 0, EN_BOOSTER = 0 (default)
434 	 */
435 	if (priv->vdda_uv < 2700000) {
436 		if (priv->syscfg && priv->vdd_uv > 2700000) {
437 			ret = regulator_enable(priv->vdd);
438 			if (ret < 0) {
439 				dev_err(dev, "vdd enable failed %d\n", ret);
440 				return ret;
441 			}
442 
443 			ret = regmap_write(priv->syscfg,
444 					   STM32MP1_SYSCFG_PMCSETR,
445 					   STM32MP1_SYSCFG_ANASWVDD_MASK);
446 			if (ret < 0) {
447 				regulator_disable(priv->vdd);
448 				dev_err(dev, "vdd select failed, %d\n", ret);
449 				return ret;
450 			}
451 			dev_dbg(dev, "analog switches supplied by vdd\n");
452 
453 			return 0;
454 		}
455 
456 		if (priv->booster) {
457 			/*
458 			 * This is optional, as this is a trade-off between
459 			 * analog performance and power consumption.
460 			 */
461 			ret = regulator_enable(priv->booster);
462 			if (ret < 0) {
463 				dev_err(dev, "booster enable failed %d\n", ret);
464 				return ret;
465 			}
466 			dev_dbg(dev, "analog switches supplied by booster\n");
467 
468 			return 0;
469 		}
470 	}
471 
472 	/* Fallback using vdda (default), nothing to do */
473 	dev_dbg(dev, "analog switches supplied by vdda (%d uV)\n",
474 		priv->vdda_uv);
475 
476 	return 0;
477 }
478 
479 static void stm32_adc_core_switches_supply_dis(struct stm32_adc_priv *priv)
480 {
481 	if (priv->vdda_uv < 2700000) {
482 		if (priv->syscfg && priv->vdd_uv > 2700000) {
483 			regmap_write(priv->syscfg, STM32MP1_SYSCFG_PMCCLRR,
484 				     STM32MP1_SYSCFG_ANASWVDD_MASK);
485 			regulator_disable(priv->vdd);
486 			return;
487 		}
488 		if (priv->booster)
489 			regulator_disable(priv->booster);
490 	}
491 }
492 
493 static int stm32_adc_core_hw_start(struct device *dev)
494 {
495 	struct stm32_adc_common *common = dev_get_drvdata(dev);
496 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
497 	int ret;
498 
499 	ret = regulator_enable(priv->vdda);
500 	if (ret < 0) {
501 		dev_err(dev, "vdda enable failed %d\n", ret);
502 		return ret;
503 	}
504 
505 	ret = regulator_get_voltage(priv->vdda);
506 	if (ret < 0) {
507 		dev_err(dev, "vdda get voltage failed, %d\n", ret);
508 		goto err_vdda_disable;
509 	}
510 	priv->vdda_uv = ret;
511 
512 	ret = stm32_adc_core_switches_supply_en(priv, dev);
513 	if (ret < 0)
514 		goto err_vdda_disable;
515 
516 	ret = regulator_enable(priv->vref);
517 	if (ret < 0) {
518 		dev_err(dev, "vref enable failed\n");
519 		goto err_switches_dis;
520 	}
521 
522 	if (priv->bclk) {
523 		ret = clk_prepare_enable(priv->bclk);
524 		if (ret < 0) {
525 			dev_err(dev, "bus clk enable failed\n");
526 			goto err_regulator_disable;
527 		}
528 	}
529 
530 	if (priv->aclk) {
531 		ret = clk_prepare_enable(priv->aclk);
532 		if (ret < 0) {
533 			dev_err(dev, "adc clk enable failed\n");
534 			goto err_bclk_disable;
535 		}
536 	}
537 
538 	writel_relaxed(priv->ccr_bak, priv->common.base + priv->cfg->regs->ccr);
539 
540 	return 0;
541 
542 err_bclk_disable:
543 	if (priv->bclk)
544 		clk_disable_unprepare(priv->bclk);
545 err_regulator_disable:
546 	regulator_disable(priv->vref);
547 err_switches_dis:
548 	stm32_adc_core_switches_supply_dis(priv);
549 err_vdda_disable:
550 	regulator_disable(priv->vdda);
551 
552 	return ret;
553 }
554 
555 static void stm32_adc_core_hw_stop(struct device *dev)
556 {
557 	struct stm32_adc_common *common = dev_get_drvdata(dev);
558 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
559 
560 	/* Backup CCR that may be lost (depends on power state to achieve) */
561 	priv->ccr_bak = readl_relaxed(priv->common.base + priv->cfg->regs->ccr);
562 	if (priv->aclk)
563 		clk_disable_unprepare(priv->aclk);
564 	if (priv->bclk)
565 		clk_disable_unprepare(priv->bclk);
566 	regulator_disable(priv->vref);
567 	stm32_adc_core_switches_supply_dis(priv);
568 	regulator_disable(priv->vdda);
569 }
570 
571 static int stm32_adc_core_switches_probe(struct device *dev,
572 					 struct stm32_adc_priv *priv)
573 {
574 	struct device_node *np = dev->of_node;
575 	int ret;
576 
577 	/* Analog switches supply can be controlled by syscfg (optional) */
578 	priv->syscfg = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
579 	if (IS_ERR(priv->syscfg)) {
580 		ret = PTR_ERR(priv->syscfg);
581 		if (ret != -ENODEV) {
582 			if (ret != -EPROBE_DEFER)
583 				dev_err(dev, "Can't probe syscfg: %d\n", ret);
584 			return ret;
585 		}
586 		priv->syscfg = NULL;
587 	}
588 
589 	/* Booster can be used to supply analog switches (optional) */
590 	if (priv->cfg->has_syscfg & HAS_VBOOSTER &&
591 	    of_property_read_bool(np, "booster-supply")) {
592 		priv->booster = devm_regulator_get_optional(dev, "booster");
593 		if (IS_ERR(priv->booster)) {
594 			ret = PTR_ERR(priv->booster);
595 			if (ret != -ENODEV) {
596 				if (ret != -EPROBE_DEFER)
597 					dev_err(dev, "can't get booster %d\n",
598 						ret);
599 				return ret;
600 			}
601 			priv->booster = NULL;
602 		}
603 	}
604 
605 	/* Vdd can be used to supply analog switches (optional) */
606 	if (priv->cfg->has_syscfg & HAS_ANASWVDD &&
607 	    of_property_read_bool(np, "vdd-supply")) {
608 		priv->vdd = devm_regulator_get_optional(dev, "vdd");
609 		if (IS_ERR(priv->vdd)) {
610 			ret = PTR_ERR(priv->vdd);
611 			if (ret != -ENODEV) {
612 				if (ret != -EPROBE_DEFER)
613 					dev_err(dev, "can't get vdd %d\n", ret);
614 				return ret;
615 			}
616 			priv->vdd = NULL;
617 		}
618 	}
619 
620 	if (priv->vdd) {
621 		ret = regulator_enable(priv->vdd);
622 		if (ret < 0) {
623 			dev_err(dev, "vdd enable failed %d\n", ret);
624 			return ret;
625 		}
626 
627 		ret = regulator_get_voltage(priv->vdd);
628 		if (ret < 0) {
629 			dev_err(dev, "vdd get voltage failed %d\n", ret);
630 			regulator_disable(priv->vdd);
631 			return ret;
632 		}
633 		priv->vdd_uv = ret;
634 
635 		regulator_disable(priv->vdd);
636 	}
637 
638 	return 0;
639 }
640 
641 static int stm32_adc_probe(struct platform_device *pdev)
642 {
643 	struct stm32_adc_priv *priv;
644 	struct device *dev = &pdev->dev;
645 	struct device_node *np = pdev->dev.of_node;
646 	struct resource *res;
647 	int ret;
648 
649 	if (!pdev->dev.of_node)
650 		return -ENODEV;
651 
652 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
653 	if (!priv)
654 		return -ENOMEM;
655 	platform_set_drvdata(pdev, &priv->common);
656 
657 	priv->cfg = (const struct stm32_adc_priv_cfg *)
658 		of_match_device(dev->driver->of_match_table, dev)->data;
659 
660 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
661 	priv->common.base = devm_ioremap_resource(&pdev->dev, res);
662 	if (IS_ERR(priv->common.base))
663 		return PTR_ERR(priv->common.base);
664 	priv->common.phys_base = res->start;
665 
666 	priv->vdda = devm_regulator_get(&pdev->dev, "vdda");
667 	if (IS_ERR(priv->vdda)) {
668 		ret = PTR_ERR(priv->vdda);
669 		if (ret != -EPROBE_DEFER)
670 			dev_err(&pdev->dev, "vdda get failed, %d\n", ret);
671 		return ret;
672 	}
673 
674 	priv->vref = devm_regulator_get(&pdev->dev, "vref");
675 	if (IS_ERR(priv->vref)) {
676 		ret = PTR_ERR(priv->vref);
677 		dev_err(&pdev->dev, "vref get failed, %d\n", ret);
678 		return ret;
679 	}
680 
681 	priv->aclk = devm_clk_get(&pdev->dev, "adc");
682 	if (IS_ERR(priv->aclk)) {
683 		ret = PTR_ERR(priv->aclk);
684 		if (ret != -ENOENT) {
685 			dev_err(&pdev->dev, "Can't get 'adc' clock\n");
686 			return ret;
687 		}
688 		priv->aclk = NULL;
689 	}
690 
691 	priv->bclk = devm_clk_get(&pdev->dev, "bus");
692 	if (IS_ERR(priv->bclk)) {
693 		ret = PTR_ERR(priv->bclk);
694 		if (ret != -ENOENT) {
695 			dev_err(&pdev->dev, "Can't get 'bus' clock\n");
696 			return ret;
697 		}
698 		priv->bclk = NULL;
699 	}
700 
701 	ret = stm32_adc_core_switches_probe(dev, priv);
702 	if (ret)
703 		return ret;
704 
705 	pm_runtime_get_noresume(dev);
706 	pm_runtime_set_active(dev);
707 	pm_runtime_set_autosuspend_delay(dev, STM32_ADC_CORE_SLEEP_DELAY_MS);
708 	pm_runtime_use_autosuspend(dev);
709 	pm_runtime_enable(dev);
710 
711 	ret = stm32_adc_core_hw_start(dev);
712 	if (ret)
713 		goto err_pm_stop;
714 
715 	ret = regulator_get_voltage(priv->vref);
716 	if (ret < 0) {
717 		dev_err(&pdev->dev, "vref get voltage failed, %d\n", ret);
718 		goto err_hw_stop;
719 	}
720 	priv->common.vref_mv = ret / 1000;
721 	dev_dbg(&pdev->dev, "vref+=%dmV\n", priv->common.vref_mv);
722 
723 	ret = priv->cfg->clk_sel(pdev, priv);
724 	if (ret < 0)
725 		goto err_hw_stop;
726 
727 	ret = stm32_adc_irq_probe(pdev, priv);
728 	if (ret < 0)
729 		goto err_hw_stop;
730 
731 	ret = of_platform_populate(np, NULL, NULL, &pdev->dev);
732 	if (ret < 0) {
733 		dev_err(&pdev->dev, "failed to populate DT children\n");
734 		goto err_irq_remove;
735 	}
736 
737 	pm_runtime_mark_last_busy(dev);
738 	pm_runtime_put_autosuspend(dev);
739 
740 	return 0;
741 
742 err_irq_remove:
743 	stm32_adc_irq_remove(pdev, priv);
744 err_hw_stop:
745 	stm32_adc_core_hw_stop(dev);
746 err_pm_stop:
747 	pm_runtime_disable(dev);
748 	pm_runtime_set_suspended(dev);
749 	pm_runtime_put_noidle(dev);
750 
751 	return ret;
752 }
753 
754 static int stm32_adc_remove(struct platform_device *pdev)
755 {
756 	struct stm32_adc_common *common = platform_get_drvdata(pdev);
757 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
758 
759 	pm_runtime_get_sync(&pdev->dev);
760 	of_platform_depopulate(&pdev->dev);
761 	stm32_adc_irq_remove(pdev, priv);
762 	stm32_adc_core_hw_stop(&pdev->dev);
763 	pm_runtime_disable(&pdev->dev);
764 	pm_runtime_set_suspended(&pdev->dev);
765 	pm_runtime_put_noidle(&pdev->dev);
766 
767 	return 0;
768 }
769 
770 #if defined(CONFIG_PM)
771 static int stm32_adc_core_runtime_suspend(struct device *dev)
772 {
773 	stm32_adc_core_hw_stop(dev);
774 
775 	return 0;
776 }
777 
778 static int stm32_adc_core_runtime_resume(struct device *dev)
779 {
780 	return stm32_adc_core_hw_start(dev);
781 }
782 #endif
783 
784 static const struct dev_pm_ops stm32_adc_core_pm_ops = {
785 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
786 				pm_runtime_force_resume)
787 	SET_RUNTIME_PM_OPS(stm32_adc_core_runtime_suspend,
788 			   stm32_adc_core_runtime_resume,
789 			   NULL)
790 };
791 
792 static const struct stm32_adc_priv_cfg stm32f4_adc_priv_cfg = {
793 	.regs = &stm32f4_adc_common_regs,
794 	.clk_sel = stm32f4_adc_clk_sel,
795 	.max_clk_rate_hz = 36000000,
796 };
797 
798 static const struct stm32_adc_priv_cfg stm32h7_adc_priv_cfg = {
799 	.regs = &stm32h7_adc_common_regs,
800 	.clk_sel = stm32h7_adc_clk_sel,
801 	.max_clk_rate_hz = 36000000,
802 	.has_syscfg = HAS_VBOOSTER,
803 };
804 
805 static const struct stm32_adc_priv_cfg stm32mp1_adc_priv_cfg = {
806 	.regs = &stm32h7_adc_common_regs,
807 	.clk_sel = stm32h7_adc_clk_sel,
808 	.max_clk_rate_hz = 40000000,
809 	.has_syscfg = HAS_VBOOSTER | HAS_ANASWVDD,
810 };
811 
812 static const struct of_device_id stm32_adc_of_match[] = {
813 	{
814 		.compatible = "st,stm32f4-adc-core",
815 		.data = (void *)&stm32f4_adc_priv_cfg
816 	}, {
817 		.compatible = "st,stm32h7-adc-core",
818 		.data = (void *)&stm32h7_adc_priv_cfg
819 	}, {
820 		.compatible = "st,stm32mp1-adc-core",
821 		.data = (void *)&stm32mp1_adc_priv_cfg
822 	}, {
823 	},
824 };
825 MODULE_DEVICE_TABLE(of, stm32_adc_of_match);
826 
827 static struct platform_driver stm32_adc_driver = {
828 	.probe = stm32_adc_probe,
829 	.remove = stm32_adc_remove,
830 	.driver = {
831 		.name = "stm32-adc-core",
832 		.of_match_table = stm32_adc_of_match,
833 		.pm = &stm32_adc_core_pm_ops,
834 	},
835 };
836 module_platform_driver(stm32_adc_driver);
837 
838 MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
839 MODULE_DESCRIPTION("STMicroelectronics STM32 ADC core driver");
840 MODULE_LICENSE("GPL v2");
841 MODULE_ALIAS("platform:stm32-adc-core");
842