xref: /openbmc/linux/drivers/iio/adc/stm32-adc-core.c (revision d9e32672)
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  * stm32_adc_common_regs - stm32 common registers, compatible dependent data
42  * @csr:	common status register offset
43  * @ccr:	common control register offset
44  * @eoc1:	adc1 end of conversion flag in @csr
45  * @eoc2:	adc2 end of conversion flag in @csr
46  * @eoc3:	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  * 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  * @booster:		booster supply reference
83  * @vdd:		vdd supply reference
84  * @vdda:		vdda analog supply reference
85  * @vref:		regulator reference
86  * @vdd_uv:		vdd supply voltage (microvolts)
87  * @vdda_uv:		vdda supply voltage (microvolts)
88  * @cfg:		compatible configuration data
89  * @common:		common data for all ADC instances
90  * @ccr_bak:		backup CCR in low power mode
91  * @syscfg:		reference to syscon, system control registers
92  */
93 struct stm32_adc_priv {
94 	int				irq[STM32_ADC_MAX_ADCS];
95 	struct irq_domain		*domain;
96 	struct clk			*aclk;
97 	struct clk			*bclk;
98 	struct regulator		*booster;
99 	struct regulator		*vdd;
100 	struct regulator		*vdda;
101 	struct regulator		*vref;
102 	int				vdd_uv;
103 	int				vdda_uv;
104 	const struct stm32_adc_priv_cfg	*cfg;
105 	struct stm32_adc_common		common;
106 	u32				ccr_bak;
107 	struct regmap			*syscfg;
108 };
109 
110 static struct stm32_adc_priv *to_stm32_adc_priv(struct stm32_adc_common *com)
111 {
112 	return container_of(com, struct stm32_adc_priv, common);
113 }
114 
115 /* STM32F4 ADC internal common clock prescaler division ratios */
116 static int stm32f4_pclk_div[] = {2, 4, 6, 8};
117 
118 /**
119  * stm32f4_adc_clk_sel() - Select stm32f4 ADC common clock prescaler
120  * @priv: stm32 ADC core private data
121  * Select clock prescaler used for analog conversions, before using ADC.
122  */
123 static int stm32f4_adc_clk_sel(struct platform_device *pdev,
124 			       struct stm32_adc_priv *priv)
125 {
126 	unsigned long rate;
127 	u32 val;
128 	int i;
129 
130 	/* stm32f4 has one clk input for analog (mandatory), enforce it here */
131 	if (!priv->aclk) {
132 		dev_err(&pdev->dev, "No 'adc' clock found\n");
133 		return -ENOENT;
134 	}
135 
136 	rate = clk_get_rate(priv->aclk);
137 	if (!rate) {
138 		dev_err(&pdev->dev, "Invalid clock rate: 0\n");
139 		return -EINVAL;
140 	}
141 
142 	for (i = 0; i < ARRAY_SIZE(stm32f4_pclk_div); i++) {
143 		if ((rate / stm32f4_pclk_div[i]) <= priv->cfg->max_clk_rate_hz)
144 			break;
145 	}
146 	if (i >= ARRAY_SIZE(stm32f4_pclk_div)) {
147 		dev_err(&pdev->dev, "adc clk selection failed\n");
148 		return -EINVAL;
149 	}
150 
151 	priv->common.rate = rate / stm32f4_pclk_div[i];
152 	val = readl_relaxed(priv->common.base + STM32F4_ADC_CCR);
153 	val &= ~STM32F4_ADC_ADCPRE_MASK;
154 	val |= i << STM32F4_ADC_ADCPRE_SHIFT;
155 	writel_relaxed(val, priv->common.base + STM32F4_ADC_CCR);
156 
157 	dev_dbg(&pdev->dev, "Using analog clock source at %ld kHz\n",
158 		priv->common.rate / 1000);
159 
160 	return 0;
161 }
162 
163 /**
164  * struct stm32h7_adc_ck_spec - specification for stm32h7 adc clock
165  * @ckmode: ADC clock mode, Async or sync with prescaler.
166  * @presc: prescaler bitfield for async clock mode
167  * @div: prescaler division ratio
168  */
169 struct stm32h7_adc_ck_spec {
170 	u32 ckmode;
171 	u32 presc;
172 	int div;
173 };
174 
175 static const struct stm32h7_adc_ck_spec stm32h7_adc_ckmodes_spec[] = {
176 	/* 00: CK_ADC[1..3]: Asynchronous clock modes */
177 	{ 0, 0, 1 },
178 	{ 0, 1, 2 },
179 	{ 0, 2, 4 },
180 	{ 0, 3, 6 },
181 	{ 0, 4, 8 },
182 	{ 0, 5, 10 },
183 	{ 0, 6, 12 },
184 	{ 0, 7, 16 },
185 	{ 0, 8, 32 },
186 	{ 0, 9, 64 },
187 	{ 0, 10, 128 },
188 	{ 0, 11, 256 },
189 	/* HCLK used: Synchronous clock modes (1, 2 or 4 prescaler) */
190 	{ 1, 0, 1 },
191 	{ 2, 0, 2 },
192 	{ 3, 0, 4 },
193 };
194 
195 static int stm32h7_adc_clk_sel(struct platform_device *pdev,
196 			       struct stm32_adc_priv *priv)
197 {
198 	u32 ckmode, presc, val;
199 	unsigned long rate;
200 	int i, div;
201 
202 	/* stm32h7 bus clock is common for all ADC instances (mandatory) */
203 	if (!priv->bclk) {
204 		dev_err(&pdev->dev, "No 'bus' clock found\n");
205 		return -ENOENT;
206 	}
207 
208 	/*
209 	 * stm32h7 can use either 'bus' or 'adc' clock for analog circuitry.
210 	 * So, choice is to have bus clock mandatory and adc clock optional.
211 	 * If optional 'adc' clock has been found, then try to use it first.
212 	 */
213 	if (priv->aclk) {
214 		/*
215 		 * Asynchronous clock modes (e.g. ckmode == 0)
216 		 * From spec: PLL output musn't exceed max rate
217 		 */
218 		rate = clk_get_rate(priv->aclk);
219 		if (!rate) {
220 			dev_err(&pdev->dev, "Invalid adc clock rate: 0\n");
221 			return -EINVAL;
222 		}
223 
224 		for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
225 			ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
226 			presc = stm32h7_adc_ckmodes_spec[i].presc;
227 			div = stm32h7_adc_ckmodes_spec[i].div;
228 
229 			if (ckmode)
230 				continue;
231 
232 			if ((rate / div) <= priv->cfg->max_clk_rate_hz)
233 				goto out;
234 		}
235 	}
236 
237 	/* Synchronous clock modes (e.g. ckmode is 1, 2 or 3) */
238 	rate = clk_get_rate(priv->bclk);
239 	if (!rate) {
240 		dev_err(&pdev->dev, "Invalid bus clock rate: 0\n");
241 		return -EINVAL;
242 	}
243 
244 	for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
245 		ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
246 		presc = stm32h7_adc_ckmodes_spec[i].presc;
247 		div = stm32h7_adc_ckmodes_spec[i].div;
248 
249 		if (!ckmode)
250 			continue;
251 
252 		if ((rate / div) <= priv->cfg->max_clk_rate_hz)
253 			goto out;
254 	}
255 
256 	dev_err(&pdev->dev, "adc clk selection failed\n");
257 	return -EINVAL;
258 
259 out:
260 	/* rate used later by each ADC instance to control BOOST mode */
261 	priv->common.rate = rate / div;
262 
263 	/* Set common clock mode and prescaler */
264 	val = readl_relaxed(priv->common.base + STM32H7_ADC_CCR);
265 	val &= ~(STM32H7_CKMODE_MASK | STM32H7_PRESC_MASK);
266 	val |= ckmode << STM32H7_CKMODE_SHIFT;
267 	val |= presc << STM32H7_PRESC_SHIFT;
268 	writel_relaxed(val, priv->common.base + STM32H7_ADC_CCR);
269 
270 	dev_dbg(&pdev->dev, "Using %s clock/%d source at %ld kHz\n",
271 		ckmode ? "bus" : "adc", div, priv->common.rate / 1000);
272 
273 	return 0;
274 }
275 
276 /* STM32F4 common registers definitions */
277 static const struct stm32_adc_common_regs stm32f4_adc_common_regs = {
278 	.csr = STM32F4_ADC_CSR,
279 	.ccr = STM32F4_ADC_CCR,
280 	.eoc1_msk = STM32F4_EOC1,
281 	.eoc2_msk = STM32F4_EOC2,
282 	.eoc3_msk = STM32F4_EOC3,
283 	.ier = STM32F4_ADC_CR1,
284 	.eocie_msk = STM32F4_EOCIE,
285 };
286 
287 /* STM32H7 common registers definitions */
288 static const struct stm32_adc_common_regs stm32h7_adc_common_regs = {
289 	.csr = STM32H7_ADC_CSR,
290 	.ccr = STM32H7_ADC_CCR,
291 	.eoc1_msk = STM32H7_EOC_MST,
292 	.eoc2_msk = STM32H7_EOC_SLV,
293 	.ier = STM32H7_ADC_IER,
294 	.eocie_msk = STM32H7_EOCIE,
295 };
296 
297 static const unsigned int stm32_adc_offset[STM32_ADC_MAX_ADCS] = {
298 	0, STM32_ADC_OFFSET, STM32_ADC_OFFSET * 2,
299 };
300 
301 static unsigned int stm32_adc_eoc_enabled(struct stm32_adc_priv *priv,
302 					  unsigned int adc)
303 {
304 	u32 ier, offset = stm32_adc_offset[adc];
305 
306 	ier = readl_relaxed(priv->common.base + offset + priv->cfg->regs->ier);
307 
308 	return ier & priv->cfg->regs->eocie_msk;
309 }
310 
311 /* ADC common interrupt for all instances */
312 static void stm32_adc_irq_handler(struct irq_desc *desc)
313 {
314 	struct stm32_adc_priv *priv = irq_desc_get_handler_data(desc);
315 	struct irq_chip *chip = irq_desc_get_chip(desc);
316 	u32 status;
317 
318 	chained_irq_enter(chip, desc);
319 	status = readl_relaxed(priv->common.base + priv->cfg->regs->csr);
320 
321 	/*
322 	 * End of conversion may be handled by using IRQ or DMA. There may be a
323 	 * race here when two conversions complete at the same time on several
324 	 * ADCs. EOC may be read 'set' for several ADCs, with:
325 	 * - an ADC configured to use DMA (EOC triggers the DMA request, and
326 	 *   is then automatically cleared by DR read in hardware)
327 	 * - an ADC configured to use IRQs (EOCIE bit is set. The handler must
328 	 *   be called in this case)
329 	 * So both EOC status bit in CSR and EOCIE control bit must be checked
330 	 * before invoking the interrupt handler (e.g. call ISR only for
331 	 * IRQ-enabled ADCs).
332 	 */
333 	if (status & priv->cfg->regs->eoc1_msk &&
334 	    stm32_adc_eoc_enabled(priv, 0))
335 		generic_handle_irq(irq_find_mapping(priv->domain, 0));
336 
337 	if (status & priv->cfg->regs->eoc2_msk &&
338 	    stm32_adc_eoc_enabled(priv, 1))
339 		generic_handle_irq(irq_find_mapping(priv->domain, 1));
340 
341 	if (status & priv->cfg->regs->eoc3_msk &&
342 	    stm32_adc_eoc_enabled(priv, 2))
343 		generic_handle_irq(irq_find_mapping(priv->domain, 2));
344 
345 	chained_irq_exit(chip, desc);
346 };
347 
348 static int stm32_adc_domain_map(struct irq_domain *d, unsigned int irq,
349 				irq_hw_number_t hwirq)
350 {
351 	irq_set_chip_data(irq, d->host_data);
352 	irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_level_irq);
353 
354 	return 0;
355 }
356 
357 static void stm32_adc_domain_unmap(struct irq_domain *d, unsigned int irq)
358 {
359 	irq_set_chip_and_handler(irq, NULL, NULL);
360 	irq_set_chip_data(irq, NULL);
361 }
362 
363 static const struct irq_domain_ops stm32_adc_domain_ops = {
364 	.map = stm32_adc_domain_map,
365 	.unmap  = stm32_adc_domain_unmap,
366 	.xlate = irq_domain_xlate_onecell,
367 };
368 
369 static int stm32_adc_irq_probe(struct platform_device *pdev,
370 			       struct stm32_adc_priv *priv)
371 {
372 	struct device_node *np = pdev->dev.of_node;
373 	unsigned int i;
374 
375 	for (i = 0; i < STM32_ADC_MAX_ADCS; i++) {
376 		priv->irq[i] = platform_get_irq(pdev, i);
377 		if (priv->irq[i] < 0) {
378 			/*
379 			 * At least one interrupt must be provided, make others
380 			 * optional:
381 			 * - stm32f4/h7 shares a common interrupt.
382 			 * - stm32mp1, has one line per ADC (either for ADC1,
383 			 *   ADC2 or both).
384 			 */
385 			if (i && priv->irq[i] == -ENXIO)
386 				continue;
387 
388 			return priv->irq[i];
389 		}
390 	}
391 
392 	priv->domain = irq_domain_add_simple(np, STM32_ADC_MAX_ADCS, 0,
393 					     &stm32_adc_domain_ops,
394 					     priv);
395 	if (!priv->domain) {
396 		dev_err(&pdev->dev, "Failed to add irq domain\n");
397 		return -ENOMEM;
398 	}
399 
400 	for (i = 0; i < STM32_ADC_MAX_ADCS; i++) {
401 		if (priv->irq[i] < 0)
402 			continue;
403 		irq_set_chained_handler(priv->irq[i], stm32_adc_irq_handler);
404 		irq_set_handler_data(priv->irq[i], priv);
405 	}
406 
407 	return 0;
408 }
409 
410 static void stm32_adc_irq_remove(struct platform_device *pdev,
411 				 struct stm32_adc_priv *priv)
412 {
413 	int hwirq;
414 	unsigned int i;
415 
416 	for (hwirq = 0; hwirq < STM32_ADC_MAX_ADCS; hwirq++)
417 		irq_dispose_mapping(irq_find_mapping(priv->domain, hwirq));
418 	irq_domain_remove(priv->domain);
419 
420 	for (i = 0; i < STM32_ADC_MAX_ADCS; i++) {
421 		if (priv->irq[i] < 0)
422 			continue;
423 		irq_set_chained_handler(priv->irq[i], NULL);
424 	}
425 }
426 
427 static int stm32_adc_core_switches_supply_en(struct stm32_adc_priv *priv,
428 					     struct device *dev)
429 {
430 	int ret;
431 
432 	/*
433 	 * On STM32H7 and STM32MP1, the ADC inputs are multiplexed with analog
434 	 * switches (via PCSEL) which have reduced performances when their
435 	 * supply is below 2.7V (vdda by default):
436 	 * - Voltage booster can be used, to get full ADC performances
437 	 *   (increases power consumption).
438 	 * - Vdd can be used to supply them, if above 2.7V (STM32MP1 only).
439 	 *
440 	 * Recommended settings for ANASWVDD and EN_BOOSTER:
441 	 * - vdda < 2.7V but vdd > 2.7V: ANASWVDD = 1, EN_BOOSTER = 0 (stm32mp1)
442 	 * - vdda < 2.7V and vdd < 2.7V: ANASWVDD = 0, EN_BOOSTER = 1
443 	 * - vdda >= 2.7V:               ANASWVDD = 0, EN_BOOSTER = 0 (default)
444 	 */
445 	if (priv->vdda_uv < 2700000) {
446 		if (priv->syscfg && priv->vdd_uv > 2700000) {
447 			ret = regulator_enable(priv->vdd);
448 			if (ret < 0) {
449 				dev_err(dev, "vdd enable failed %d\n", ret);
450 				return ret;
451 			}
452 
453 			ret = regmap_write(priv->syscfg,
454 					   STM32MP1_SYSCFG_PMCSETR,
455 					   STM32MP1_SYSCFG_ANASWVDD_MASK);
456 			if (ret < 0) {
457 				regulator_disable(priv->vdd);
458 				dev_err(dev, "vdd select failed, %d\n", ret);
459 				return ret;
460 			}
461 			dev_dbg(dev, "analog switches supplied by vdd\n");
462 
463 			return 0;
464 		}
465 
466 		if (priv->booster) {
467 			/*
468 			 * This is optional, as this is a trade-off between
469 			 * analog performance and power consumption.
470 			 */
471 			ret = regulator_enable(priv->booster);
472 			if (ret < 0) {
473 				dev_err(dev, "booster enable failed %d\n", ret);
474 				return ret;
475 			}
476 			dev_dbg(dev, "analog switches supplied by booster\n");
477 
478 			return 0;
479 		}
480 	}
481 
482 	/* Fallback using vdda (default), nothing to do */
483 	dev_dbg(dev, "analog switches supplied by vdda (%d uV)\n",
484 		priv->vdda_uv);
485 
486 	return 0;
487 }
488 
489 static void stm32_adc_core_switches_supply_dis(struct stm32_adc_priv *priv)
490 {
491 	if (priv->vdda_uv < 2700000) {
492 		if (priv->syscfg && priv->vdd_uv > 2700000) {
493 			regmap_write(priv->syscfg, STM32MP1_SYSCFG_PMCCLRR,
494 				     STM32MP1_SYSCFG_ANASWVDD_MASK);
495 			regulator_disable(priv->vdd);
496 			return;
497 		}
498 		if (priv->booster)
499 			regulator_disable(priv->booster);
500 	}
501 }
502 
503 static int stm32_adc_core_hw_start(struct device *dev)
504 {
505 	struct stm32_adc_common *common = dev_get_drvdata(dev);
506 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
507 	int ret;
508 
509 	ret = regulator_enable(priv->vdda);
510 	if (ret < 0) {
511 		dev_err(dev, "vdda enable failed %d\n", ret);
512 		return ret;
513 	}
514 
515 	ret = regulator_get_voltage(priv->vdda);
516 	if (ret < 0) {
517 		dev_err(dev, "vdda get voltage failed, %d\n", ret);
518 		goto err_vdda_disable;
519 	}
520 	priv->vdda_uv = ret;
521 
522 	ret = stm32_adc_core_switches_supply_en(priv, dev);
523 	if (ret < 0)
524 		goto err_vdda_disable;
525 
526 	ret = regulator_enable(priv->vref);
527 	if (ret < 0) {
528 		dev_err(dev, "vref enable failed\n");
529 		goto err_switches_dis;
530 	}
531 
532 	if (priv->bclk) {
533 		ret = clk_prepare_enable(priv->bclk);
534 		if (ret < 0) {
535 			dev_err(dev, "bus clk enable failed\n");
536 			goto err_regulator_disable;
537 		}
538 	}
539 
540 	if (priv->aclk) {
541 		ret = clk_prepare_enable(priv->aclk);
542 		if (ret < 0) {
543 			dev_err(dev, "adc clk enable failed\n");
544 			goto err_bclk_disable;
545 		}
546 	}
547 
548 	writel_relaxed(priv->ccr_bak, priv->common.base + priv->cfg->regs->ccr);
549 
550 	return 0;
551 
552 err_bclk_disable:
553 	if (priv->bclk)
554 		clk_disable_unprepare(priv->bclk);
555 err_regulator_disable:
556 	regulator_disable(priv->vref);
557 err_switches_dis:
558 	stm32_adc_core_switches_supply_dis(priv);
559 err_vdda_disable:
560 	regulator_disable(priv->vdda);
561 
562 	return ret;
563 }
564 
565 static void stm32_adc_core_hw_stop(struct device *dev)
566 {
567 	struct stm32_adc_common *common = dev_get_drvdata(dev);
568 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
569 
570 	/* Backup CCR that may be lost (depends on power state to achieve) */
571 	priv->ccr_bak = readl_relaxed(priv->common.base + priv->cfg->regs->ccr);
572 	if (priv->aclk)
573 		clk_disable_unprepare(priv->aclk);
574 	if (priv->bclk)
575 		clk_disable_unprepare(priv->bclk);
576 	regulator_disable(priv->vref);
577 	stm32_adc_core_switches_supply_dis(priv);
578 	regulator_disable(priv->vdda);
579 }
580 
581 static int stm32_adc_core_switches_probe(struct device *dev,
582 					 struct stm32_adc_priv *priv)
583 {
584 	struct device_node *np = dev->of_node;
585 	int ret;
586 
587 	/* Analog switches supply can be controlled by syscfg (optional) */
588 	priv->syscfg = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
589 	if (IS_ERR(priv->syscfg)) {
590 		ret = PTR_ERR(priv->syscfg);
591 		if (ret != -ENODEV) {
592 			if (ret != -EPROBE_DEFER)
593 				dev_err(dev, "Can't probe syscfg: %d\n", ret);
594 			return ret;
595 		}
596 		priv->syscfg = NULL;
597 	}
598 
599 	/* Booster can be used to supply analog switches (optional) */
600 	if (priv->cfg->has_syscfg & HAS_VBOOSTER &&
601 	    of_property_read_bool(np, "booster-supply")) {
602 		priv->booster = devm_regulator_get_optional(dev, "booster");
603 		if (IS_ERR(priv->booster)) {
604 			ret = PTR_ERR(priv->booster);
605 			if (ret != -ENODEV) {
606 				if (ret != -EPROBE_DEFER)
607 					dev_err(dev, "can't get booster %d\n",
608 						ret);
609 				return ret;
610 			}
611 			priv->booster = NULL;
612 		}
613 	}
614 
615 	/* Vdd can be used to supply analog switches (optional) */
616 	if (priv->cfg->has_syscfg & HAS_ANASWVDD &&
617 	    of_property_read_bool(np, "vdd-supply")) {
618 		priv->vdd = devm_regulator_get_optional(dev, "vdd");
619 		if (IS_ERR(priv->vdd)) {
620 			ret = PTR_ERR(priv->vdd);
621 			if (ret != -ENODEV) {
622 				if (ret != -EPROBE_DEFER)
623 					dev_err(dev, "can't get vdd %d\n", ret);
624 				return ret;
625 			}
626 			priv->vdd = NULL;
627 		}
628 	}
629 
630 	if (priv->vdd) {
631 		ret = regulator_enable(priv->vdd);
632 		if (ret < 0) {
633 			dev_err(dev, "vdd enable failed %d\n", ret);
634 			return ret;
635 		}
636 
637 		ret = regulator_get_voltage(priv->vdd);
638 		if (ret < 0) {
639 			dev_err(dev, "vdd get voltage failed %d\n", ret);
640 			regulator_disable(priv->vdd);
641 			return ret;
642 		}
643 		priv->vdd_uv = ret;
644 
645 		regulator_disable(priv->vdd);
646 	}
647 
648 	return 0;
649 }
650 
651 static int stm32_adc_probe(struct platform_device *pdev)
652 {
653 	struct stm32_adc_priv *priv;
654 	struct device *dev = &pdev->dev;
655 	struct device_node *np = pdev->dev.of_node;
656 	struct resource *res;
657 	int ret;
658 
659 	if (!pdev->dev.of_node)
660 		return -ENODEV;
661 
662 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
663 	if (!priv)
664 		return -ENOMEM;
665 	platform_set_drvdata(pdev, &priv->common);
666 
667 	priv->cfg = (const struct stm32_adc_priv_cfg *)
668 		of_match_device(dev->driver->of_match_table, dev)->data;
669 
670 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
671 	priv->common.base = devm_ioremap_resource(&pdev->dev, res);
672 	if (IS_ERR(priv->common.base))
673 		return PTR_ERR(priv->common.base);
674 	priv->common.phys_base = res->start;
675 
676 	priv->vdda = devm_regulator_get(&pdev->dev, "vdda");
677 	if (IS_ERR(priv->vdda)) {
678 		ret = PTR_ERR(priv->vdda);
679 		if (ret != -EPROBE_DEFER)
680 			dev_err(&pdev->dev, "vdda get failed, %d\n", ret);
681 		return ret;
682 	}
683 
684 	priv->vref = devm_regulator_get(&pdev->dev, "vref");
685 	if (IS_ERR(priv->vref)) {
686 		ret = PTR_ERR(priv->vref);
687 		dev_err(&pdev->dev, "vref get failed, %d\n", ret);
688 		return ret;
689 	}
690 
691 	priv->aclk = devm_clk_get(&pdev->dev, "adc");
692 	if (IS_ERR(priv->aclk)) {
693 		ret = PTR_ERR(priv->aclk);
694 		if (ret != -ENOENT) {
695 			dev_err(&pdev->dev, "Can't get 'adc' clock\n");
696 			return ret;
697 		}
698 		priv->aclk = NULL;
699 	}
700 
701 	priv->bclk = devm_clk_get(&pdev->dev, "bus");
702 	if (IS_ERR(priv->bclk)) {
703 		ret = PTR_ERR(priv->bclk);
704 		if (ret != -ENOENT) {
705 			dev_err(&pdev->dev, "Can't get 'bus' clock\n");
706 			return ret;
707 		}
708 		priv->bclk = NULL;
709 	}
710 
711 	ret = stm32_adc_core_switches_probe(dev, priv);
712 	if (ret)
713 		return ret;
714 
715 	pm_runtime_get_noresume(dev);
716 	pm_runtime_set_active(dev);
717 	pm_runtime_set_autosuspend_delay(dev, STM32_ADC_CORE_SLEEP_DELAY_MS);
718 	pm_runtime_use_autosuspend(dev);
719 	pm_runtime_enable(dev);
720 
721 	ret = stm32_adc_core_hw_start(dev);
722 	if (ret)
723 		goto err_pm_stop;
724 
725 	ret = regulator_get_voltage(priv->vref);
726 	if (ret < 0) {
727 		dev_err(&pdev->dev, "vref get voltage failed, %d\n", ret);
728 		goto err_hw_stop;
729 	}
730 	priv->common.vref_mv = ret / 1000;
731 	dev_dbg(&pdev->dev, "vref+=%dmV\n", priv->common.vref_mv);
732 
733 	ret = priv->cfg->clk_sel(pdev, priv);
734 	if (ret < 0)
735 		goto err_hw_stop;
736 
737 	ret = stm32_adc_irq_probe(pdev, priv);
738 	if (ret < 0)
739 		goto err_hw_stop;
740 
741 	ret = of_platform_populate(np, NULL, NULL, &pdev->dev);
742 	if (ret < 0) {
743 		dev_err(&pdev->dev, "failed to populate DT children\n");
744 		goto err_irq_remove;
745 	}
746 
747 	pm_runtime_mark_last_busy(dev);
748 	pm_runtime_put_autosuspend(dev);
749 
750 	return 0;
751 
752 err_irq_remove:
753 	stm32_adc_irq_remove(pdev, priv);
754 err_hw_stop:
755 	stm32_adc_core_hw_stop(dev);
756 err_pm_stop:
757 	pm_runtime_disable(dev);
758 	pm_runtime_set_suspended(dev);
759 	pm_runtime_put_noidle(dev);
760 
761 	return ret;
762 }
763 
764 static int stm32_adc_remove(struct platform_device *pdev)
765 {
766 	struct stm32_adc_common *common = platform_get_drvdata(pdev);
767 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
768 
769 	pm_runtime_get_sync(&pdev->dev);
770 	of_platform_depopulate(&pdev->dev);
771 	stm32_adc_irq_remove(pdev, priv);
772 	stm32_adc_core_hw_stop(&pdev->dev);
773 	pm_runtime_disable(&pdev->dev);
774 	pm_runtime_set_suspended(&pdev->dev);
775 	pm_runtime_put_noidle(&pdev->dev);
776 
777 	return 0;
778 }
779 
780 #if defined(CONFIG_PM)
781 static int stm32_adc_core_runtime_suspend(struct device *dev)
782 {
783 	stm32_adc_core_hw_stop(dev);
784 
785 	return 0;
786 }
787 
788 static int stm32_adc_core_runtime_resume(struct device *dev)
789 {
790 	return stm32_adc_core_hw_start(dev);
791 }
792 #endif
793 
794 static const struct dev_pm_ops stm32_adc_core_pm_ops = {
795 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
796 				pm_runtime_force_resume)
797 	SET_RUNTIME_PM_OPS(stm32_adc_core_runtime_suspend,
798 			   stm32_adc_core_runtime_resume,
799 			   NULL)
800 };
801 
802 static const struct stm32_adc_priv_cfg stm32f4_adc_priv_cfg = {
803 	.regs = &stm32f4_adc_common_regs,
804 	.clk_sel = stm32f4_adc_clk_sel,
805 	.max_clk_rate_hz = 36000000,
806 };
807 
808 static const struct stm32_adc_priv_cfg stm32h7_adc_priv_cfg = {
809 	.regs = &stm32h7_adc_common_regs,
810 	.clk_sel = stm32h7_adc_clk_sel,
811 	.max_clk_rate_hz = 36000000,
812 	.has_syscfg = HAS_VBOOSTER,
813 };
814 
815 static const struct stm32_adc_priv_cfg stm32mp1_adc_priv_cfg = {
816 	.regs = &stm32h7_adc_common_regs,
817 	.clk_sel = stm32h7_adc_clk_sel,
818 	.max_clk_rate_hz = 40000000,
819 	.has_syscfg = HAS_VBOOSTER | HAS_ANASWVDD,
820 };
821 
822 static const struct of_device_id stm32_adc_of_match[] = {
823 	{
824 		.compatible = "st,stm32f4-adc-core",
825 		.data = (void *)&stm32f4_adc_priv_cfg
826 	}, {
827 		.compatible = "st,stm32h7-adc-core",
828 		.data = (void *)&stm32h7_adc_priv_cfg
829 	}, {
830 		.compatible = "st,stm32mp1-adc-core",
831 		.data = (void *)&stm32mp1_adc_priv_cfg
832 	}, {
833 	},
834 };
835 MODULE_DEVICE_TABLE(of, stm32_adc_of_match);
836 
837 static struct platform_driver stm32_adc_driver = {
838 	.probe = stm32_adc_probe,
839 	.remove = stm32_adc_remove,
840 	.driver = {
841 		.name = "stm32-adc-core",
842 		.of_match_table = stm32_adc_of_match,
843 		.pm = &stm32_adc_core_pm_ops,
844 	},
845 };
846 module_platform_driver(stm32_adc_driver);
847 
848 MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
849 MODULE_DESCRIPTION("STMicroelectronics STM32 ADC core driver");
850 MODULE_LICENSE("GPL v2");
851 MODULE_ALIAS("platform:stm32-adc-core");
852