xref: /openbmc/linux/drivers/iio/adc/stm32-adc-core.c (revision e1cd7b80)
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 #define STM32_ADC_CORE_SLEEP_DELAY_MS	2000
28 
29 /* SYSCFG registers */
30 #define STM32MP1_SYSCFG_PMCSETR		0x04
31 #define STM32MP1_SYSCFG_PMCCLRR		0x44
32 
33 /* SYSCFG bit fields */
34 #define STM32MP1_SYSCFG_ANASWVDD_MASK	BIT(9)
35 
36 /* SYSCFG capability flags */
37 #define HAS_VBOOSTER		BIT(0)
38 #define HAS_ANASWVDD		BIT(1)
39 
40 /**
41  * struct stm32_adc_common_regs - stm32 common registers
42  * @csr:	common status register offset
43  * @ccr:	common control register offset
44  * @eoc1_msk:	adc1 end of conversion flag in @csr
45  * @eoc2_msk:	adc2 end of conversion flag in @csr
46  * @eoc3_msk:	adc3 end of conversion flag in @csr
47  * @ier:	interrupt enable register offset for each adc
48  * @eocie_msk:	end of conversion interrupt enable mask in @ier
49  */
50 struct stm32_adc_common_regs {
51 	u32 csr;
52 	u32 ccr;
53 	u32 eoc1_msk;
54 	u32 eoc2_msk;
55 	u32 eoc3_msk;
56 	u32 ier;
57 	u32 eocie_msk;
58 };
59 
60 struct stm32_adc_priv;
61 
62 /**
63  * struct stm32_adc_priv_cfg - stm32 core compatible configuration data
64  * @regs:	common registers for all instances
65  * @clk_sel:	clock selection routine
66  * @max_clk_rate_hz: maximum analog clock rate (Hz, from datasheet)
67  * @has_syscfg: SYSCFG capability flags
68  */
69 struct stm32_adc_priv_cfg {
70 	const struct stm32_adc_common_regs *regs;
71 	int (*clk_sel)(struct platform_device *, struct stm32_adc_priv *);
72 	u32 max_clk_rate_hz;
73 	unsigned int has_syscfg;
74 };
75 
76 /**
77  * struct stm32_adc_priv - stm32 ADC core private data
78  * @irq:		irq(s) for ADC block
79  * @domain:		irq domain reference
80  * @aclk:		clock reference for the analog circuitry
81  * @bclk:		bus clock common for all ADCs, depends on part used
82  * @max_clk_rate:	desired maximum clock rate
83  * @booster:		booster supply reference
84  * @vdd:		vdd supply reference
85  * @vdda:		vdda analog supply reference
86  * @vref:		regulator reference
87  * @vdd_uv:		vdd supply voltage (microvolts)
88  * @vdda_uv:		vdda supply voltage (microvolts)
89  * @cfg:		compatible configuration data
90  * @common:		common data for all ADC instances
91  * @ccr_bak:		backup CCR in low power mode
92  * @syscfg:		reference to syscon, system control registers
93  */
94 struct stm32_adc_priv {
95 	int				irq[STM32_ADC_MAX_ADCS];
96 	struct irq_domain		*domain;
97 	struct clk			*aclk;
98 	struct clk			*bclk;
99 	u32				max_clk_rate;
100 	struct regulator		*booster;
101 	struct regulator		*vdd;
102 	struct regulator		*vdda;
103 	struct regulator		*vref;
104 	int				vdd_uv;
105 	int				vdda_uv;
106 	const struct stm32_adc_priv_cfg	*cfg;
107 	struct stm32_adc_common		common;
108 	u32				ccr_bak;
109 	struct regmap			*syscfg;
110 };
111 
112 static struct stm32_adc_priv *to_stm32_adc_priv(struct stm32_adc_common *com)
113 {
114 	return container_of(com, struct stm32_adc_priv, common);
115 }
116 
117 /* STM32F4 ADC internal common clock prescaler division ratios */
118 static int stm32f4_pclk_div[] = {2, 4, 6, 8};
119 
120 /**
121  * stm32f4_adc_clk_sel() - Select stm32f4 ADC common clock prescaler
122  * @pdev: platform device
123  * @priv: stm32 ADC core private data
124  * Select clock prescaler used for analog conversions, before using ADC.
125  */
126 static int stm32f4_adc_clk_sel(struct platform_device *pdev,
127 			       struct stm32_adc_priv *priv)
128 {
129 	unsigned long rate;
130 	u32 val;
131 	int i;
132 
133 	/* stm32f4 has one clk input for analog (mandatory), enforce it here */
134 	if (!priv->aclk) {
135 		dev_err(&pdev->dev, "No 'adc' clock found\n");
136 		return -ENOENT;
137 	}
138 
139 	rate = clk_get_rate(priv->aclk);
140 	if (!rate) {
141 		dev_err(&pdev->dev, "Invalid clock rate: 0\n");
142 		return -EINVAL;
143 	}
144 
145 	for (i = 0; i < ARRAY_SIZE(stm32f4_pclk_div); i++) {
146 		if ((rate / stm32f4_pclk_div[i]) <= priv->max_clk_rate)
147 			break;
148 	}
149 	if (i >= ARRAY_SIZE(stm32f4_pclk_div)) {
150 		dev_err(&pdev->dev, "adc clk selection failed\n");
151 		return -EINVAL;
152 	}
153 
154 	priv->common.rate = rate / stm32f4_pclk_div[i];
155 	val = readl_relaxed(priv->common.base + STM32F4_ADC_CCR);
156 	val &= ~STM32F4_ADC_ADCPRE_MASK;
157 	val |= i << STM32F4_ADC_ADCPRE_SHIFT;
158 	writel_relaxed(val, priv->common.base + STM32F4_ADC_CCR);
159 
160 	dev_dbg(&pdev->dev, "Using analog clock source at %ld kHz\n",
161 		priv->common.rate / 1000);
162 
163 	return 0;
164 }
165 
166 /**
167  * struct stm32h7_adc_ck_spec - specification for stm32h7 adc clock
168  * @ckmode: ADC clock mode, Async or sync with prescaler.
169  * @presc: prescaler bitfield for async clock mode
170  * @div: prescaler division ratio
171  */
172 struct stm32h7_adc_ck_spec {
173 	u32 ckmode;
174 	u32 presc;
175 	int div;
176 };
177 
178 static const struct stm32h7_adc_ck_spec stm32h7_adc_ckmodes_spec[] = {
179 	/* 00: CK_ADC[1..3]: Asynchronous clock modes */
180 	{ 0, 0, 1 },
181 	{ 0, 1, 2 },
182 	{ 0, 2, 4 },
183 	{ 0, 3, 6 },
184 	{ 0, 4, 8 },
185 	{ 0, 5, 10 },
186 	{ 0, 6, 12 },
187 	{ 0, 7, 16 },
188 	{ 0, 8, 32 },
189 	{ 0, 9, 64 },
190 	{ 0, 10, 128 },
191 	{ 0, 11, 256 },
192 	/* HCLK used: Synchronous clock modes (1, 2 or 4 prescaler) */
193 	{ 1, 0, 1 },
194 	{ 2, 0, 2 },
195 	{ 3, 0, 4 },
196 };
197 
198 static int stm32h7_adc_clk_sel(struct platform_device *pdev,
199 			       struct stm32_adc_priv *priv)
200 {
201 	u32 ckmode, presc, val;
202 	unsigned long rate;
203 	int i, div;
204 
205 	/* stm32h7 bus clock is common for all ADC instances (mandatory) */
206 	if (!priv->bclk) {
207 		dev_err(&pdev->dev, "No 'bus' clock found\n");
208 		return -ENOENT;
209 	}
210 
211 	/*
212 	 * stm32h7 can use either 'bus' or 'adc' clock for analog circuitry.
213 	 * So, choice is to have bus clock mandatory and adc clock optional.
214 	 * If optional 'adc' clock has been found, then try to use it first.
215 	 */
216 	if (priv->aclk) {
217 		/*
218 		 * Asynchronous clock modes (e.g. ckmode == 0)
219 		 * From spec: PLL output musn't exceed max rate
220 		 */
221 		rate = clk_get_rate(priv->aclk);
222 		if (!rate) {
223 			dev_err(&pdev->dev, "Invalid adc clock rate: 0\n");
224 			return -EINVAL;
225 		}
226 
227 		for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
228 			ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
229 			presc = stm32h7_adc_ckmodes_spec[i].presc;
230 			div = stm32h7_adc_ckmodes_spec[i].div;
231 
232 			if (ckmode)
233 				continue;
234 
235 			if ((rate / div) <= priv->max_clk_rate)
236 				goto out;
237 		}
238 	}
239 
240 	/* Synchronous clock modes (e.g. ckmode is 1, 2 or 3) */
241 	rate = clk_get_rate(priv->bclk);
242 	if (!rate) {
243 		dev_err(&pdev->dev, "Invalid bus 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->max_clk_rate)
256 			goto out;
257 	}
258 
259 	dev_err(&pdev->dev, "adc clk selection failed\n");
260 	return -EINVAL;
261 
262 out:
263 	/* rate used later by each ADC instance to control BOOST mode */
264 	priv->common.rate = rate / div;
265 
266 	/* Set common clock mode and prescaler */
267 	val = readl_relaxed(priv->common.base + STM32H7_ADC_CCR);
268 	val &= ~(STM32H7_CKMODE_MASK | STM32H7_PRESC_MASK);
269 	val |= ckmode << STM32H7_CKMODE_SHIFT;
270 	val |= presc << STM32H7_PRESC_SHIFT;
271 	writel_relaxed(val, priv->common.base + STM32H7_ADC_CCR);
272 
273 	dev_dbg(&pdev->dev, "Using %s clock/%d source at %ld kHz\n",
274 		ckmode ? "bus" : "adc", div, priv->common.rate / 1000);
275 
276 	return 0;
277 }
278 
279 /* STM32F4 common registers definitions */
280 static const struct stm32_adc_common_regs stm32f4_adc_common_regs = {
281 	.csr = STM32F4_ADC_CSR,
282 	.ccr = STM32F4_ADC_CCR,
283 	.eoc1_msk = STM32F4_EOC1,
284 	.eoc2_msk = STM32F4_EOC2,
285 	.eoc3_msk = STM32F4_EOC3,
286 	.ier = STM32F4_ADC_CR1,
287 	.eocie_msk = STM32F4_EOCIE,
288 };
289 
290 /* STM32H7 common registers definitions */
291 static const struct stm32_adc_common_regs stm32h7_adc_common_regs = {
292 	.csr = STM32H7_ADC_CSR,
293 	.ccr = STM32H7_ADC_CCR,
294 	.eoc1_msk = STM32H7_EOC_MST,
295 	.eoc2_msk = STM32H7_EOC_SLV,
296 	.ier = STM32H7_ADC_IER,
297 	.eocie_msk = STM32H7_EOCIE,
298 };
299 
300 static const unsigned int stm32_adc_offset[STM32_ADC_MAX_ADCS] = {
301 	0, STM32_ADC_OFFSET, STM32_ADC_OFFSET * 2,
302 };
303 
304 static unsigned int stm32_adc_eoc_enabled(struct stm32_adc_priv *priv,
305 					  unsigned int adc)
306 {
307 	u32 ier, offset = stm32_adc_offset[adc];
308 
309 	ier = readl_relaxed(priv->common.base + offset + priv->cfg->regs->ier);
310 
311 	return ier & priv->cfg->regs->eocie_msk;
312 }
313 
314 /* ADC common interrupt for all instances */
315 static void stm32_adc_irq_handler(struct irq_desc *desc)
316 {
317 	struct stm32_adc_priv *priv = irq_desc_get_handler_data(desc);
318 	struct irq_chip *chip = irq_desc_get_chip(desc);
319 	u32 status;
320 
321 	chained_irq_enter(chip, desc);
322 	status = readl_relaxed(priv->common.base + priv->cfg->regs->csr);
323 
324 	/*
325 	 * End of conversion may be handled by using IRQ or DMA. There may be a
326 	 * race here when two conversions complete at the same time on several
327 	 * ADCs. EOC may be read 'set' for several ADCs, with:
328 	 * - an ADC configured to use DMA (EOC triggers the DMA request, and
329 	 *   is then automatically cleared by DR read in hardware)
330 	 * - an ADC configured to use IRQs (EOCIE bit is set. The handler must
331 	 *   be called in this case)
332 	 * So both EOC status bit in CSR and EOCIE control bit must be checked
333 	 * before invoking the interrupt handler (e.g. call ISR only for
334 	 * IRQ-enabled ADCs).
335 	 */
336 	if (status & priv->cfg->regs->eoc1_msk &&
337 	    stm32_adc_eoc_enabled(priv, 0))
338 		generic_handle_irq(irq_find_mapping(priv->domain, 0));
339 
340 	if (status & priv->cfg->regs->eoc2_msk &&
341 	    stm32_adc_eoc_enabled(priv, 1))
342 		generic_handle_irq(irq_find_mapping(priv->domain, 1));
343 
344 	if (status & priv->cfg->regs->eoc3_msk &&
345 	    stm32_adc_eoc_enabled(priv, 2))
346 		generic_handle_irq(irq_find_mapping(priv->domain, 2));
347 
348 	chained_irq_exit(chip, desc);
349 };
350 
351 static int stm32_adc_domain_map(struct irq_domain *d, unsigned int irq,
352 				irq_hw_number_t hwirq)
353 {
354 	irq_set_chip_data(irq, d->host_data);
355 	irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_level_irq);
356 
357 	return 0;
358 }
359 
360 static void stm32_adc_domain_unmap(struct irq_domain *d, unsigned int irq)
361 {
362 	irq_set_chip_and_handler(irq, NULL, NULL);
363 	irq_set_chip_data(irq, NULL);
364 }
365 
366 static const struct irq_domain_ops stm32_adc_domain_ops = {
367 	.map = stm32_adc_domain_map,
368 	.unmap  = stm32_adc_domain_unmap,
369 	.xlate = irq_domain_xlate_onecell,
370 };
371 
372 static int stm32_adc_irq_probe(struct platform_device *pdev,
373 			       struct stm32_adc_priv *priv)
374 {
375 	struct device_node *np = pdev->dev.of_node;
376 	unsigned int i;
377 
378 	for (i = 0; i < STM32_ADC_MAX_ADCS; i++) {
379 		priv->irq[i] = platform_get_irq(pdev, i);
380 		if (priv->irq[i] < 0) {
381 			/*
382 			 * At least one interrupt must be provided, make others
383 			 * optional:
384 			 * - stm32f4/h7 shares a common interrupt.
385 			 * - stm32mp1, has one line per ADC (either for ADC1,
386 			 *   ADC2 or both).
387 			 */
388 			if (i && priv->irq[i] == -ENXIO)
389 				continue;
390 
391 			return priv->irq[i];
392 		}
393 	}
394 
395 	priv->domain = irq_domain_add_simple(np, STM32_ADC_MAX_ADCS, 0,
396 					     &stm32_adc_domain_ops,
397 					     priv);
398 	if (!priv->domain) {
399 		dev_err(&pdev->dev, "Failed to add irq domain\n");
400 		return -ENOMEM;
401 	}
402 
403 	for (i = 0; i < STM32_ADC_MAX_ADCS; i++) {
404 		if (priv->irq[i] < 0)
405 			continue;
406 		irq_set_chained_handler(priv->irq[i], stm32_adc_irq_handler);
407 		irq_set_handler_data(priv->irq[i], priv);
408 	}
409 
410 	return 0;
411 }
412 
413 static void stm32_adc_irq_remove(struct platform_device *pdev,
414 				 struct stm32_adc_priv *priv)
415 {
416 	int hwirq;
417 	unsigned int i;
418 
419 	for (hwirq = 0; hwirq < STM32_ADC_MAX_ADCS; hwirq++)
420 		irq_dispose_mapping(irq_find_mapping(priv->domain, hwirq));
421 	irq_domain_remove(priv->domain);
422 
423 	for (i = 0; i < STM32_ADC_MAX_ADCS; i++) {
424 		if (priv->irq[i] < 0)
425 			continue;
426 		irq_set_chained_handler(priv->irq[i], NULL);
427 	}
428 }
429 
430 static int stm32_adc_core_switches_supply_en(struct stm32_adc_priv *priv,
431 					     struct device *dev)
432 {
433 	int ret;
434 
435 	/*
436 	 * On STM32H7 and STM32MP1, the ADC inputs are multiplexed with analog
437 	 * switches (via PCSEL) which have reduced performances when their
438 	 * supply is below 2.7V (vdda by default):
439 	 * - Voltage booster can be used, to get full ADC performances
440 	 *   (increases power consumption).
441 	 * - Vdd can be used to supply them, if above 2.7V (STM32MP1 only).
442 	 *
443 	 * Recommended settings for ANASWVDD and EN_BOOSTER:
444 	 * - vdda < 2.7V but vdd > 2.7V: ANASWVDD = 1, EN_BOOSTER = 0 (stm32mp1)
445 	 * - vdda < 2.7V and vdd < 2.7V: ANASWVDD = 0, EN_BOOSTER = 1
446 	 * - vdda >= 2.7V:               ANASWVDD = 0, EN_BOOSTER = 0 (default)
447 	 */
448 	if (priv->vdda_uv < 2700000) {
449 		if (priv->syscfg && priv->vdd_uv > 2700000) {
450 			ret = regulator_enable(priv->vdd);
451 			if (ret < 0) {
452 				dev_err(dev, "vdd enable failed %d\n", ret);
453 				return ret;
454 			}
455 
456 			ret = regmap_write(priv->syscfg,
457 					   STM32MP1_SYSCFG_PMCSETR,
458 					   STM32MP1_SYSCFG_ANASWVDD_MASK);
459 			if (ret < 0) {
460 				regulator_disable(priv->vdd);
461 				dev_err(dev, "vdd select failed, %d\n", ret);
462 				return ret;
463 			}
464 			dev_dbg(dev, "analog switches supplied by vdd\n");
465 
466 			return 0;
467 		}
468 
469 		if (priv->booster) {
470 			/*
471 			 * This is optional, as this is a trade-off between
472 			 * analog performance and power consumption.
473 			 */
474 			ret = regulator_enable(priv->booster);
475 			if (ret < 0) {
476 				dev_err(dev, "booster enable failed %d\n", ret);
477 				return ret;
478 			}
479 			dev_dbg(dev, "analog switches supplied by booster\n");
480 
481 			return 0;
482 		}
483 	}
484 
485 	/* Fallback using vdda (default), nothing to do */
486 	dev_dbg(dev, "analog switches supplied by vdda (%d uV)\n",
487 		priv->vdda_uv);
488 
489 	return 0;
490 }
491 
492 static void stm32_adc_core_switches_supply_dis(struct stm32_adc_priv *priv)
493 {
494 	if (priv->vdda_uv < 2700000) {
495 		if (priv->syscfg && priv->vdd_uv > 2700000) {
496 			regmap_write(priv->syscfg, STM32MP1_SYSCFG_PMCCLRR,
497 				     STM32MP1_SYSCFG_ANASWVDD_MASK);
498 			regulator_disable(priv->vdd);
499 			return;
500 		}
501 		if (priv->booster)
502 			regulator_disable(priv->booster);
503 	}
504 }
505 
506 static int stm32_adc_core_hw_start(struct device *dev)
507 {
508 	struct stm32_adc_common *common = dev_get_drvdata(dev);
509 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
510 	int ret;
511 
512 	ret = regulator_enable(priv->vdda);
513 	if (ret < 0) {
514 		dev_err(dev, "vdda enable failed %d\n", ret);
515 		return ret;
516 	}
517 
518 	ret = regulator_get_voltage(priv->vdda);
519 	if (ret < 0) {
520 		dev_err(dev, "vdda get voltage failed, %d\n", ret);
521 		goto err_vdda_disable;
522 	}
523 	priv->vdda_uv = ret;
524 
525 	ret = stm32_adc_core_switches_supply_en(priv, dev);
526 	if (ret < 0)
527 		goto err_vdda_disable;
528 
529 	ret = regulator_enable(priv->vref);
530 	if (ret < 0) {
531 		dev_err(dev, "vref enable failed\n");
532 		goto err_switches_dis;
533 	}
534 
535 	if (priv->bclk) {
536 		ret = clk_prepare_enable(priv->bclk);
537 		if (ret < 0) {
538 			dev_err(dev, "bus clk enable failed\n");
539 			goto err_regulator_disable;
540 		}
541 	}
542 
543 	if (priv->aclk) {
544 		ret = clk_prepare_enable(priv->aclk);
545 		if (ret < 0) {
546 			dev_err(dev, "adc clk enable failed\n");
547 			goto err_bclk_disable;
548 		}
549 	}
550 
551 	writel_relaxed(priv->ccr_bak, priv->common.base + priv->cfg->regs->ccr);
552 
553 	return 0;
554 
555 err_bclk_disable:
556 	if (priv->bclk)
557 		clk_disable_unprepare(priv->bclk);
558 err_regulator_disable:
559 	regulator_disable(priv->vref);
560 err_switches_dis:
561 	stm32_adc_core_switches_supply_dis(priv);
562 err_vdda_disable:
563 	regulator_disable(priv->vdda);
564 
565 	return ret;
566 }
567 
568 static void stm32_adc_core_hw_stop(struct device *dev)
569 {
570 	struct stm32_adc_common *common = dev_get_drvdata(dev);
571 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
572 
573 	/* Backup CCR that may be lost (depends on power state to achieve) */
574 	priv->ccr_bak = readl_relaxed(priv->common.base + priv->cfg->regs->ccr);
575 	if (priv->aclk)
576 		clk_disable_unprepare(priv->aclk);
577 	if (priv->bclk)
578 		clk_disable_unprepare(priv->bclk);
579 	regulator_disable(priv->vref);
580 	stm32_adc_core_switches_supply_dis(priv);
581 	regulator_disable(priv->vdda);
582 }
583 
584 static int stm32_adc_core_switches_probe(struct device *dev,
585 					 struct stm32_adc_priv *priv)
586 {
587 	struct device_node *np = dev->of_node;
588 	int ret;
589 
590 	/* Analog switches supply can be controlled by syscfg (optional) */
591 	priv->syscfg = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
592 	if (IS_ERR(priv->syscfg)) {
593 		ret = PTR_ERR(priv->syscfg);
594 		if (ret != -ENODEV) {
595 			if (ret != -EPROBE_DEFER)
596 				dev_err(dev, "Can't probe syscfg: %d\n", ret);
597 			return ret;
598 		}
599 		priv->syscfg = NULL;
600 	}
601 
602 	/* Booster can be used to supply analog switches (optional) */
603 	if (priv->cfg->has_syscfg & HAS_VBOOSTER &&
604 	    of_property_read_bool(np, "booster-supply")) {
605 		priv->booster = devm_regulator_get_optional(dev, "booster");
606 		if (IS_ERR(priv->booster)) {
607 			ret = PTR_ERR(priv->booster);
608 			if (ret != -ENODEV) {
609 				if (ret != -EPROBE_DEFER)
610 					dev_err(dev, "can't get booster %d\n",
611 						ret);
612 				return ret;
613 			}
614 			priv->booster = NULL;
615 		}
616 	}
617 
618 	/* Vdd can be used to supply analog switches (optional) */
619 	if (priv->cfg->has_syscfg & HAS_ANASWVDD &&
620 	    of_property_read_bool(np, "vdd-supply")) {
621 		priv->vdd = devm_regulator_get_optional(dev, "vdd");
622 		if (IS_ERR(priv->vdd)) {
623 			ret = PTR_ERR(priv->vdd);
624 			if (ret != -ENODEV) {
625 				if (ret != -EPROBE_DEFER)
626 					dev_err(dev, "can't get vdd %d\n", ret);
627 				return ret;
628 			}
629 			priv->vdd = NULL;
630 		}
631 	}
632 
633 	if (priv->vdd) {
634 		ret = regulator_enable(priv->vdd);
635 		if (ret < 0) {
636 			dev_err(dev, "vdd enable failed %d\n", ret);
637 			return ret;
638 		}
639 
640 		ret = regulator_get_voltage(priv->vdd);
641 		if (ret < 0) {
642 			dev_err(dev, "vdd get voltage failed %d\n", ret);
643 			regulator_disable(priv->vdd);
644 			return ret;
645 		}
646 		priv->vdd_uv = ret;
647 
648 		regulator_disable(priv->vdd);
649 	}
650 
651 	return 0;
652 }
653 
654 static int stm32_adc_probe(struct platform_device *pdev)
655 {
656 	struct stm32_adc_priv *priv;
657 	struct device *dev = &pdev->dev;
658 	struct device_node *np = pdev->dev.of_node;
659 	struct resource *res;
660 	u32 max_rate;
661 	int ret;
662 
663 	if (!pdev->dev.of_node)
664 		return -ENODEV;
665 
666 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
667 	if (!priv)
668 		return -ENOMEM;
669 	platform_set_drvdata(pdev, &priv->common);
670 
671 	priv->cfg = (const struct stm32_adc_priv_cfg *)
672 		of_match_device(dev->driver->of_match_table, dev)->data;
673 
674 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
675 	priv->common.base = devm_ioremap_resource(&pdev->dev, res);
676 	if (IS_ERR(priv->common.base))
677 		return PTR_ERR(priv->common.base);
678 	priv->common.phys_base = res->start;
679 
680 	priv->vdda = devm_regulator_get(&pdev->dev, "vdda");
681 	if (IS_ERR(priv->vdda)) {
682 		ret = PTR_ERR(priv->vdda);
683 		if (ret != -EPROBE_DEFER)
684 			dev_err(&pdev->dev, "vdda get failed, %d\n", ret);
685 		return ret;
686 	}
687 
688 	priv->vref = devm_regulator_get(&pdev->dev, "vref");
689 	if (IS_ERR(priv->vref)) {
690 		ret = PTR_ERR(priv->vref);
691 		dev_err(&pdev->dev, "vref get failed, %d\n", ret);
692 		return ret;
693 	}
694 
695 	priv->aclk = devm_clk_get(&pdev->dev, "adc");
696 	if (IS_ERR(priv->aclk)) {
697 		ret = PTR_ERR(priv->aclk);
698 		if (ret != -ENOENT) {
699 			dev_err(&pdev->dev, "Can't get 'adc' clock\n");
700 			return ret;
701 		}
702 		priv->aclk = NULL;
703 	}
704 
705 	priv->bclk = devm_clk_get(&pdev->dev, "bus");
706 	if (IS_ERR(priv->bclk)) {
707 		ret = PTR_ERR(priv->bclk);
708 		if (ret != -ENOENT) {
709 			dev_err(&pdev->dev, "Can't get 'bus' clock\n");
710 			return ret;
711 		}
712 		priv->bclk = NULL;
713 	}
714 
715 	ret = stm32_adc_core_switches_probe(dev, priv);
716 	if (ret)
717 		return ret;
718 
719 	pm_runtime_get_noresume(dev);
720 	pm_runtime_set_active(dev);
721 	pm_runtime_set_autosuspend_delay(dev, STM32_ADC_CORE_SLEEP_DELAY_MS);
722 	pm_runtime_use_autosuspend(dev);
723 	pm_runtime_enable(dev);
724 
725 	ret = stm32_adc_core_hw_start(dev);
726 	if (ret)
727 		goto err_pm_stop;
728 
729 	ret = regulator_get_voltage(priv->vref);
730 	if (ret < 0) {
731 		dev_err(&pdev->dev, "vref get voltage failed, %d\n", ret);
732 		goto err_hw_stop;
733 	}
734 	priv->common.vref_mv = ret / 1000;
735 	dev_dbg(&pdev->dev, "vref+=%dmV\n", priv->common.vref_mv);
736 
737 	ret = of_property_read_u32(pdev->dev.of_node, "st,max-clk-rate-hz",
738 				   &max_rate);
739 	if (!ret)
740 		priv->max_clk_rate = min(max_rate, priv->cfg->max_clk_rate_hz);
741 	else
742 		priv->max_clk_rate = priv->cfg->max_clk_rate_hz;
743 
744 	ret = priv->cfg->clk_sel(pdev, priv);
745 	if (ret < 0)
746 		goto err_hw_stop;
747 
748 	ret = stm32_adc_irq_probe(pdev, priv);
749 	if (ret < 0)
750 		goto err_hw_stop;
751 
752 	ret = of_platform_populate(np, NULL, NULL, &pdev->dev);
753 	if (ret < 0) {
754 		dev_err(&pdev->dev, "failed to populate DT children\n");
755 		goto err_irq_remove;
756 	}
757 
758 	pm_runtime_mark_last_busy(dev);
759 	pm_runtime_put_autosuspend(dev);
760 
761 	return 0;
762 
763 err_irq_remove:
764 	stm32_adc_irq_remove(pdev, priv);
765 err_hw_stop:
766 	stm32_adc_core_hw_stop(dev);
767 err_pm_stop:
768 	pm_runtime_disable(dev);
769 	pm_runtime_set_suspended(dev);
770 	pm_runtime_put_noidle(dev);
771 
772 	return ret;
773 }
774 
775 static int stm32_adc_remove(struct platform_device *pdev)
776 {
777 	struct stm32_adc_common *common = platform_get_drvdata(pdev);
778 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
779 
780 	pm_runtime_get_sync(&pdev->dev);
781 	of_platform_depopulate(&pdev->dev);
782 	stm32_adc_irq_remove(pdev, priv);
783 	stm32_adc_core_hw_stop(&pdev->dev);
784 	pm_runtime_disable(&pdev->dev);
785 	pm_runtime_set_suspended(&pdev->dev);
786 	pm_runtime_put_noidle(&pdev->dev);
787 
788 	return 0;
789 }
790 
791 #if defined(CONFIG_PM)
792 static int stm32_adc_core_runtime_suspend(struct device *dev)
793 {
794 	stm32_adc_core_hw_stop(dev);
795 
796 	return 0;
797 }
798 
799 static int stm32_adc_core_runtime_resume(struct device *dev)
800 {
801 	return stm32_adc_core_hw_start(dev);
802 }
803 #endif
804 
805 static const struct dev_pm_ops stm32_adc_core_pm_ops = {
806 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
807 				pm_runtime_force_resume)
808 	SET_RUNTIME_PM_OPS(stm32_adc_core_runtime_suspend,
809 			   stm32_adc_core_runtime_resume,
810 			   NULL)
811 };
812 
813 static const struct stm32_adc_priv_cfg stm32f4_adc_priv_cfg = {
814 	.regs = &stm32f4_adc_common_regs,
815 	.clk_sel = stm32f4_adc_clk_sel,
816 	.max_clk_rate_hz = 36000000,
817 };
818 
819 static const struct stm32_adc_priv_cfg stm32h7_adc_priv_cfg = {
820 	.regs = &stm32h7_adc_common_regs,
821 	.clk_sel = stm32h7_adc_clk_sel,
822 	.max_clk_rate_hz = 36000000,
823 	.has_syscfg = HAS_VBOOSTER,
824 };
825 
826 static const struct stm32_adc_priv_cfg stm32mp1_adc_priv_cfg = {
827 	.regs = &stm32h7_adc_common_regs,
828 	.clk_sel = stm32h7_adc_clk_sel,
829 	.max_clk_rate_hz = 40000000,
830 	.has_syscfg = HAS_VBOOSTER | HAS_ANASWVDD,
831 };
832 
833 static const struct of_device_id stm32_adc_of_match[] = {
834 	{
835 		.compatible = "st,stm32f4-adc-core",
836 		.data = (void *)&stm32f4_adc_priv_cfg
837 	}, {
838 		.compatible = "st,stm32h7-adc-core",
839 		.data = (void *)&stm32h7_adc_priv_cfg
840 	}, {
841 		.compatible = "st,stm32mp1-adc-core",
842 		.data = (void *)&stm32mp1_adc_priv_cfg
843 	}, {
844 	},
845 };
846 MODULE_DEVICE_TABLE(of, stm32_adc_of_match);
847 
848 static struct platform_driver stm32_adc_driver = {
849 	.probe = stm32_adc_probe,
850 	.remove = stm32_adc_remove,
851 	.driver = {
852 		.name = "stm32-adc-core",
853 		.of_match_table = stm32_adc_of_match,
854 		.pm = &stm32_adc_core_pm_ops,
855 	},
856 };
857 module_platform_driver(stm32_adc_driver);
858 
859 MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
860 MODULE_DESCRIPTION("STMicroelectronics STM32 ADC core driver");
861 MODULE_LICENSE("GPL v2");
862 MODULE_ALIAS("platform:stm32-adc-core");
863