xref: /openbmc/linux/drivers/iio/adc/stm32-adc-core.c (revision 82df5b73)
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  * @num_irqs:	number of interrupt lines
69  */
70 struct stm32_adc_priv_cfg {
71 	const struct stm32_adc_common_regs *regs;
72 	int (*clk_sel)(struct platform_device *, struct stm32_adc_priv *);
73 	u32 max_clk_rate_hz;
74 	unsigned int has_syscfg;
75 	unsigned int num_irqs;
76 };
77 
78 /**
79  * struct stm32_adc_priv - stm32 ADC core private data
80  * @irq:		irq(s) for ADC block
81  * @domain:		irq domain reference
82  * @aclk:		clock reference for the analog circuitry
83  * @bclk:		bus clock common for all ADCs, depends on part used
84  * @max_clk_rate:	desired maximum clock rate
85  * @booster:		booster supply reference
86  * @vdd:		vdd supply reference
87  * @vdda:		vdda analog supply reference
88  * @vref:		regulator reference
89  * @vdd_uv:		vdd supply voltage (microvolts)
90  * @vdda_uv:		vdda supply voltage (microvolts)
91  * @cfg:		compatible configuration data
92  * @common:		common data for all ADC instances
93  * @ccr_bak:		backup CCR in low power mode
94  * @syscfg:		reference to syscon, system control registers
95  */
96 struct stm32_adc_priv {
97 	int				irq[STM32_ADC_MAX_ADCS];
98 	struct irq_domain		*domain;
99 	struct clk			*aclk;
100 	struct clk			*bclk;
101 	u32				max_clk_rate;
102 	struct regulator		*booster;
103 	struct regulator		*vdd;
104 	struct regulator		*vdda;
105 	struct regulator		*vref;
106 	int				vdd_uv;
107 	int				vdda_uv;
108 	const struct stm32_adc_priv_cfg	*cfg;
109 	struct stm32_adc_common		common;
110 	u32				ccr_bak;
111 	struct regmap			*syscfg;
112 };
113 
114 static struct stm32_adc_priv *to_stm32_adc_priv(struct stm32_adc_common *com)
115 {
116 	return container_of(com, struct stm32_adc_priv, common);
117 }
118 
119 /* STM32F4 ADC internal common clock prescaler division ratios */
120 static int stm32f4_pclk_div[] = {2, 4, 6, 8};
121 
122 /**
123  * stm32f4_adc_clk_sel() - Select stm32f4 ADC common clock prescaler
124  * @pdev: platform device
125  * @priv: stm32 ADC core private data
126  * Select clock prescaler used for analog conversions, before using ADC.
127  */
128 static int stm32f4_adc_clk_sel(struct platform_device *pdev,
129 			       struct stm32_adc_priv *priv)
130 {
131 	unsigned long rate;
132 	u32 val;
133 	int i;
134 
135 	/* stm32f4 has one clk input for analog (mandatory), enforce it here */
136 	if (!priv->aclk) {
137 		dev_err(&pdev->dev, "No 'adc' clock found\n");
138 		return -ENOENT;
139 	}
140 
141 	rate = clk_get_rate(priv->aclk);
142 	if (!rate) {
143 		dev_err(&pdev->dev, "Invalid clock rate: 0\n");
144 		return -EINVAL;
145 	}
146 
147 	for (i = 0; i < ARRAY_SIZE(stm32f4_pclk_div); i++) {
148 		if ((rate / stm32f4_pclk_div[i]) <= priv->max_clk_rate)
149 			break;
150 	}
151 	if (i >= ARRAY_SIZE(stm32f4_pclk_div)) {
152 		dev_err(&pdev->dev, "adc clk selection failed\n");
153 		return -EINVAL;
154 	}
155 
156 	priv->common.rate = rate / stm32f4_pclk_div[i];
157 	val = readl_relaxed(priv->common.base + STM32F4_ADC_CCR);
158 	val &= ~STM32F4_ADC_ADCPRE_MASK;
159 	val |= i << STM32F4_ADC_ADCPRE_SHIFT;
160 	writel_relaxed(val, priv->common.base + STM32F4_ADC_CCR);
161 
162 	dev_dbg(&pdev->dev, "Using analog clock source at %ld kHz\n",
163 		priv->common.rate / 1000);
164 
165 	return 0;
166 }
167 
168 /**
169  * struct stm32h7_adc_ck_spec - specification for stm32h7 adc clock
170  * @ckmode: ADC clock mode, Async or sync with prescaler.
171  * @presc: prescaler bitfield for async clock mode
172  * @div: prescaler division ratio
173  */
174 struct stm32h7_adc_ck_spec {
175 	u32 ckmode;
176 	u32 presc;
177 	int div;
178 };
179 
180 static const struct stm32h7_adc_ck_spec stm32h7_adc_ckmodes_spec[] = {
181 	/* 00: CK_ADC[1..3]: Asynchronous clock modes */
182 	{ 0, 0, 1 },
183 	{ 0, 1, 2 },
184 	{ 0, 2, 4 },
185 	{ 0, 3, 6 },
186 	{ 0, 4, 8 },
187 	{ 0, 5, 10 },
188 	{ 0, 6, 12 },
189 	{ 0, 7, 16 },
190 	{ 0, 8, 32 },
191 	{ 0, 9, 64 },
192 	{ 0, 10, 128 },
193 	{ 0, 11, 256 },
194 	/* HCLK used: Synchronous clock modes (1, 2 or 4 prescaler) */
195 	{ 1, 0, 1 },
196 	{ 2, 0, 2 },
197 	{ 3, 0, 4 },
198 };
199 
200 static int stm32h7_adc_clk_sel(struct platform_device *pdev,
201 			       struct stm32_adc_priv *priv)
202 {
203 	u32 ckmode, presc, val;
204 	unsigned long rate;
205 	int i, div;
206 
207 	/* stm32h7 bus clock is common for all ADC instances (mandatory) */
208 	if (!priv->bclk) {
209 		dev_err(&pdev->dev, "No 'bus' clock found\n");
210 		return -ENOENT;
211 	}
212 
213 	/*
214 	 * stm32h7 can use either 'bus' or 'adc' clock for analog circuitry.
215 	 * So, choice is to have bus clock mandatory and adc clock optional.
216 	 * If optional 'adc' clock has been found, then try to use it first.
217 	 */
218 	if (priv->aclk) {
219 		/*
220 		 * Asynchronous clock modes (e.g. ckmode == 0)
221 		 * From spec: PLL output musn't exceed max rate
222 		 */
223 		rate = clk_get_rate(priv->aclk);
224 		if (!rate) {
225 			dev_err(&pdev->dev, "Invalid adc clock rate: 0\n");
226 			return -EINVAL;
227 		}
228 
229 		for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
230 			ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
231 			presc = stm32h7_adc_ckmodes_spec[i].presc;
232 			div = stm32h7_adc_ckmodes_spec[i].div;
233 
234 			if (ckmode)
235 				continue;
236 
237 			if ((rate / div) <= priv->max_clk_rate)
238 				goto out;
239 		}
240 	}
241 
242 	/* Synchronous clock modes (e.g. ckmode is 1, 2 or 3) */
243 	rate = clk_get_rate(priv->bclk);
244 	if (!rate) {
245 		dev_err(&pdev->dev, "Invalid bus clock rate: 0\n");
246 		return -EINVAL;
247 	}
248 
249 	for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
250 		ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
251 		presc = stm32h7_adc_ckmodes_spec[i].presc;
252 		div = stm32h7_adc_ckmodes_spec[i].div;
253 
254 		if (!ckmode)
255 			continue;
256 
257 		if ((rate / div) <= priv->max_clk_rate)
258 			goto out;
259 	}
260 
261 	dev_err(&pdev->dev, "adc clk selection failed\n");
262 	return -EINVAL;
263 
264 out:
265 	/* rate used later by each ADC instance to control BOOST mode */
266 	priv->common.rate = rate / div;
267 
268 	/* Set common clock mode and prescaler */
269 	val = readl_relaxed(priv->common.base + STM32H7_ADC_CCR);
270 	val &= ~(STM32H7_CKMODE_MASK | STM32H7_PRESC_MASK);
271 	val |= ckmode << STM32H7_CKMODE_SHIFT;
272 	val |= presc << STM32H7_PRESC_SHIFT;
273 	writel_relaxed(val, priv->common.base + STM32H7_ADC_CCR);
274 
275 	dev_dbg(&pdev->dev, "Using %s clock/%d source at %ld kHz\n",
276 		ckmode ? "bus" : "adc", div, priv->common.rate / 1000);
277 
278 	return 0;
279 }
280 
281 /* STM32F4 common registers definitions */
282 static const struct stm32_adc_common_regs stm32f4_adc_common_regs = {
283 	.csr = STM32F4_ADC_CSR,
284 	.ccr = STM32F4_ADC_CCR,
285 	.eoc1_msk = STM32F4_EOC1 | STM32F4_OVR1,
286 	.eoc2_msk = STM32F4_EOC2 | STM32F4_OVR2,
287 	.eoc3_msk = STM32F4_EOC3 | STM32F4_OVR3,
288 	.ier = STM32F4_ADC_CR1,
289 	.eocie_msk = STM32F4_EOCIE | STM32F4_OVRIE,
290 };
291 
292 /* STM32H7 common registers definitions */
293 static const struct stm32_adc_common_regs stm32h7_adc_common_regs = {
294 	.csr = STM32H7_ADC_CSR,
295 	.ccr = STM32H7_ADC_CCR,
296 	.eoc1_msk = STM32H7_EOC_MST | STM32H7_OVR_MST,
297 	.eoc2_msk = STM32H7_EOC_SLV | STM32H7_OVR_SLV,
298 	.ier = STM32H7_ADC_IER,
299 	.eocie_msk = STM32H7_EOCIE | STM32H7_OVRIE,
300 };
301 
302 static const unsigned int stm32_adc_offset[STM32_ADC_MAX_ADCS] = {
303 	0, STM32_ADC_OFFSET, STM32_ADC_OFFSET * 2,
304 };
305 
306 static unsigned int stm32_adc_eoc_enabled(struct stm32_adc_priv *priv,
307 					  unsigned int adc)
308 {
309 	u32 ier, offset = stm32_adc_offset[adc];
310 
311 	ier = readl_relaxed(priv->common.base + offset + priv->cfg->regs->ier);
312 
313 	return ier & priv->cfg->regs->eocie_msk;
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 	/*
327 	 * End of conversion may be handled by using IRQ or DMA. There may be a
328 	 * race here when two conversions complete at the same time on several
329 	 * ADCs. EOC may be read 'set' for several ADCs, with:
330 	 * - an ADC configured to use DMA (EOC triggers the DMA request, and
331 	 *   is then automatically cleared by DR read in hardware)
332 	 * - an ADC configured to use IRQs (EOCIE bit is set. The handler must
333 	 *   be called in this case)
334 	 * So both EOC status bit in CSR and EOCIE control bit must be checked
335 	 * before invoking the interrupt handler (e.g. call ISR only for
336 	 * IRQ-enabled ADCs).
337 	 */
338 	if (status & priv->cfg->regs->eoc1_msk &&
339 	    stm32_adc_eoc_enabled(priv, 0))
340 		generic_handle_irq(irq_find_mapping(priv->domain, 0));
341 
342 	if (status & priv->cfg->regs->eoc2_msk &&
343 	    stm32_adc_eoc_enabled(priv, 1))
344 		generic_handle_irq(irq_find_mapping(priv->domain, 1));
345 
346 	if (status & priv->cfg->regs->eoc3_msk &&
347 	    stm32_adc_eoc_enabled(priv, 2))
348 		generic_handle_irq(irq_find_mapping(priv->domain, 2));
349 
350 	chained_irq_exit(chip, desc);
351 };
352 
353 static int stm32_adc_domain_map(struct irq_domain *d, unsigned int irq,
354 				irq_hw_number_t hwirq)
355 {
356 	irq_set_chip_data(irq, d->host_data);
357 	irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_level_irq);
358 
359 	return 0;
360 }
361 
362 static void stm32_adc_domain_unmap(struct irq_domain *d, unsigned int irq)
363 {
364 	irq_set_chip_and_handler(irq, NULL, NULL);
365 	irq_set_chip_data(irq, NULL);
366 }
367 
368 static const struct irq_domain_ops stm32_adc_domain_ops = {
369 	.map = stm32_adc_domain_map,
370 	.unmap  = stm32_adc_domain_unmap,
371 	.xlate = irq_domain_xlate_onecell,
372 };
373 
374 static int stm32_adc_irq_probe(struct platform_device *pdev,
375 			       struct stm32_adc_priv *priv)
376 {
377 	struct device_node *np = pdev->dev.of_node;
378 	unsigned int i;
379 
380 	/*
381 	 * Interrupt(s) must be provided, depending on the compatible:
382 	 * - stm32f4/h7 shares a common interrupt line.
383 	 * - stm32mp1, has one line per ADC
384 	 */
385 	for (i = 0; i < priv->cfg->num_irqs; i++) {
386 		priv->irq[i] = platform_get_irq(pdev, i);
387 		if (priv->irq[i] < 0)
388 			return priv->irq[i];
389 	}
390 
391 	priv->domain = irq_domain_add_simple(np, STM32_ADC_MAX_ADCS, 0,
392 					     &stm32_adc_domain_ops,
393 					     priv);
394 	if (!priv->domain) {
395 		dev_err(&pdev->dev, "Failed to add irq domain\n");
396 		return -ENOMEM;
397 	}
398 
399 	for (i = 0; i < priv->cfg->num_irqs; i++) {
400 		irq_set_chained_handler(priv->irq[i], stm32_adc_irq_handler);
401 		irq_set_handler_data(priv->irq[i], priv);
402 	}
403 
404 	return 0;
405 }
406 
407 static void stm32_adc_irq_remove(struct platform_device *pdev,
408 				 struct stm32_adc_priv *priv)
409 {
410 	int hwirq;
411 	unsigned int i;
412 
413 	for (hwirq = 0; hwirq < STM32_ADC_MAX_ADCS; hwirq++)
414 		irq_dispose_mapping(irq_find_mapping(priv->domain, hwirq));
415 	irq_domain_remove(priv->domain);
416 
417 	for (i = 0; i < priv->cfg->num_irqs; i++)
418 		irq_set_chained_handler(priv->irq[i], NULL);
419 }
420 
421 static int stm32_adc_core_switches_supply_en(struct stm32_adc_priv *priv,
422 					     struct device *dev)
423 {
424 	int ret;
425 
426 	/*
427 	 * On STM32H7 and STM32MP1, the ADC inputs are multiplexed with analog
428 	 * switches (via PCSEL) which have reduced performances when their
429 	 * supply is below 2.7V (vdda by default):
430 	 * - Voltage booster can be used, to get full ADC performances
431 	 *   (increases power consumption).
432 	 * - Vdd can be used to supply them, if above 2.7V (STM32MP1 only).
433 	 *
434 	 * Recommended settings for ANASWVDD and EN_BOOSTER:
435 	 * - vdda < 2.7V but vdd > 2.7V: ANASWVDD = 1, EN_BOOSTER = 0 (stm32mp1)
436 	 * - vdda < 2.7V and vdd < 2.7V: ANASWVDD = 0, EN_BOOSTER = 1
437 	 * - vdda >= 2.7V:               ANASWVDD = 0, EN_BOOSTER = 0 (default)
438 	 */
439 	if (priv->vdda_uv < 2700000) {
440 		if (priv->syscfg && priv->vdd_uv > 2700000) {
441 			ret = regulator_enable(priv->vdd);
442 			if (ret < 0) {
443 				dev_err(dev, "vdd enable failed %d\n", ret);
444 				return ret;
445 			}
446 
447 			ret = regmap_write(priv->syscfg,
448 					   STM32MP1_SYSCFG_PMCSETR,
449 					   STM32MP1_SYSCFG_ANASWVDD_MASK);
450 			if (ret < 0) {
451 				regulator_disable(priv->vdd);
452 				dev_err(dev, "vdd select failed, %d\n", ret);
453 				return ret;
454 			}
455 			dev_dbg(dev, "analog switches supplied by vdd\n");
456 
457 			return 0;
458 		}
459 
460 		if (priv->booster) {
461 			/*
462 			 * This is optional, as this is a trade-off between
463 			 * analog performance and power consumption.
464 			 */
465 			ret = regulator_enable(priv->booster);
466 			if (ret < 0) {
467 				dev_err(dev, "booster enable failed %d\n", ret);
468 				return ret;
469 			}
470 			dev_dbg(dev, "analog switches supplied by booster\n");
471 
472 			return 0;
473 		}
474 	}
475 
476 	/* Fallback using vdda (default), nothing to do */
477 	dev_dbg(dev, "analog switches supplied by vdda (%d uV)\n",
478 		priv->vdda_uv);
479 
480 	return 0;
481 }
482 
483 static void stm32_adc_core_switches_supply_dis(struct stm32_adc_priv *priv)
484 {
485 	if (priv->vdda_uv < 2700000) {
486 		if (priv->syscfg && priv->vdd_uv > 2700000) {
487 			regmap_write(priv->syscfg, STM32MP1_SYSCFG_PMCCLRR,
488 				     STM32MP1_SYSCFG_ANASWVDD_MASK);
489 			regulator_disable(priv->vdd);
490 			return;
491 		}
492 		if (priv->booster)
493 			regulator_disable(priv->booster);
494 	}
495 }
496 
497 static int stm32_adc_core_hw_start(struct device *dev)
498 {
499 	struct stm32_adc_common *common = dev_get_drvdata(dev);
500 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
501 	int ret;
502 
503 	ret = regulator_enable(priv->vdda);
504 	if (ret < 0) {
505 		dev_err(dev, "vdda enable failed %d\n", ret);
506 		return ret;
507 	}
508 
509 	ret = regulator_get_voltage(priv->vdda);
510 	if (ret < 0) {
511 		dev_err(dev, "vdda get voltage failed, %d\n", ret);
512 		goto err_vdda_disable;
513 	}
514 	priv->vdda_uv = ret;
515 
516 	ret = stm32_adc_core_switches_supply_en(priv, dev);
517 	if (ret < 0)
518 		goto err_vdda_disable;
519 
520 	ret = regulator_enable(priv->vref);
521 	if (ret < 0) {
522 		dev_err(dev, "vref enable failed\n");
523 		goto err_switches_dis;
524 	}
525 
526 	if (priv->bclk) {
527 		ret = clk_prepare_enable(priv->bclk);
528 		if (ret < 0) {
529 			dev_err(dev, "bus clk enable failed\n");
530 			goto err_regulator_disable;
531 		}
532 	}
533 
534 	if (priv->aclk) {
535 		ret = clk_prepare_enable(priv->aclk);
536 		if (ret < 0) {
537 			dev_err(dev, "adc clk enable failed\n");
538 			goto err_bclk_disable;
539 		}
540 	}
541 
542 	writel_relaxed(priv->ccr_bak, priv->common.base + priv->cfg->regs->ccr);
543 
544 	return 0;
545 
546 err_bclk_disable:
547 	if (priv->bclk)
548 		clk_disable_unprepare(priv->bclk);
549 err_regulator_disable:
550 	regulator_disable(priv->vref);
551 err_switches_dis:
552 	stm32_adc_core_switches_supply_dis(priv);
553 err_vdda_disable:
554 	regulator_disable(priv->vdda);
555 
556 	return ret;
557 }
558 
559 static void stm32_adc_core_hw_stop(struct device *dev)
560 {
561 	struct stm32_adc_common *common = dev_get_drvdata(dev);
562 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
563 
564 	/* Backup CCR that may be lost (depends on power state to achieve) */
565 	priv->ccr_bak = readl_relaxed(priv->common.base + priv->cfg->regs->ccr);
566 	if (priv->aclk)
567 		clk_disable_unprepare(priv->aclk);
568 	if (priv->bclk)
569 		clk_disable_unprepare(priv->bclk);
570 	regulator_disable(priv->vref);
571 	stm32_adc_core_switches_supply_dis(priv);
572 	regulator_disable(priv->vdda);
573 }
574 
575 static int stm32_adc_core_switches_probe(struct device *dev,
576 					 struct stm32_adc_priv *priv)
577 {
578 	struct device_node *np = dev->of_node;
579 	int ret;
580 
581 	/* Analog switches supply can be controlled by syscfg (optional) */
582 	priv->syscfg = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
583 	if (IS_ERR(priv->syscfg)) {
584 		ret = PTR_ERR(priv->syscfg);
585 		if (ret != -ENODEV) {
586 			if (ret != -EPROBE_DEFER)
587 				dev_err(dev, "Can't probe syscfg: %d\n", ret);
588 			return ret;
589 		}
590 		priv->syscfg = NULL;
591 	}
592 
593 	/* Booster can be used to supply analog switches (optional) */
594 	if (priv->cfg->has_syscfg & HAS_VBOOSTER &&
595 	    of_property_read_bool(np, "booster-supply")) {
596 		priv->booster = devm_regulator_get_optional(dev, "booster");
597 		if (IS_ERR(priv->booster)) {
598 			ret = PTR_ERR(priv->booster);
599 			if (ret != -ENODEV) {
600 				if (ret != -EPROBE_DEFER)
601 					dev_err(dev, "can't get booster %d\n",
602 						ret);
603 				return ret;
604 			}
605 			priv->booster = NULL;
606 		}
607 	}
608 
609 	/* Vdd can be used to supply analog switches (optional) */
610 	if (priv->cfg->has_syscfg & HAS_ANASWVDD &&
611 	    of_property_read_bool(np, "vdd-supply")) {
612 		priv->vdd = devm_regulator_get_optional(dev, "vdd");
613 		if (IS_ERR(priv->vdd)) {
614 			ret = PTR_ERR(priv->vdd);
615 			if (ret != -ENODEV) {
616 				if (ret != -EPROBE_DEFER)
617 					dev_err(dev, "can't get vdd %d\n", ret);
618 				return ret;
619 			}
620 			priv->vdd = NULL;
621 		}
622 	}
623 
624 	if (priv->vdd) {
625 		ret = regulator_enable(priv->vdd);
626 		if (ret < 0) {
627 			dev_err(dev, "vdd enable failed %d\n", ret);
628 			return ret;
629 		}
630 
631 		ret = regulator_get_voltage(priv->vdd);
632 		if (ret < 0) {
633 			dev_err(dev, "vdd get voltage failed %d\n", ret);
634 			regulator_disable(priv->vdd);
635 			return ret;
636 		}
637 		priv->vdd_uv = ret;
638 
639 		regulator_disable(priv->vdd);
640 	}
641 
642 	return 0;
643 }
644 
645 static int stm32_adc_probe(struct platform_device *pdev)
646 {
647 	struct stm32_adc_priv *priv;
648 	struct device *dev = &pdev->dev;
649 	struct device_node *np = pdev->dev.of_node;
650 	struct resource *res;
651 	u32 max_rate;
652 	int ret;
653 
654 	if (!pdev->dev.of_node)
655 		return -ENODEV;
656 
657 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
658 	if (!priv)
659 		return -ENOMEM;
660 	platform_set_drvdata(pdev, &priv->common);
661 
662 	priv->cfg = (const struct stm32_adc_priv_cfg *)
663 		of_match_device(dev->driver->of_match_table, dev)->data;
664 
665 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
666 	priv->common.base = devm_ioremap_resource(&pdev->dev, res);
667 	if (IS_ERR(priv->common.base))
668 		return PTR_ERR(priv->common.base);
669 	priv->common.phys_base = res->start;
670 
671 	priv->vdda = devm_regulator_get(&pdev->dev, "vdda");
672 	if (IS_ERR(priv->vdda)) {
673 		ret = PTR_ERR(priv->vdda);
674 		if (ret != -EPROBE_DEFER)
675 			dev_err(&pdev->dev, "vdda get failed, %d\n", ret);
676 		return ret;
677 	}
678 
679 	priv->vref = devm_regulator_get(&pdev->dev, "vref");
680 	if (IS_ERR(priv->vref)) {
681 		ret = PTR_ERR(priv->vref);
682 		if (ret != -EPROBE_DEFER)
683 			dev_err(&pdev->dev, "vref get failed, %d\n", ret);
684 		return ret;
685 	}
686 
687 	priv->aclk = devm_clk_get(&pdev->dev, "adc");
688 	if (IS_ERR(priv->aclk)) {
689 		ret = PTR_ERR(priv->aclk);
690 		if (ret != -ENOENT) {
691 			if (ret != -EPROBE_DEFER)
692 				dev_err(&pdev->dev, "Can't get 'adc' clock\n");
693 			return ret;
694 		}
695 		priv->aclk = NULL;
696 	}
697 
698 	priv->bclk = devm_clk_get(&pdev->dev, "bus");
699 	if (IS_ERR(priv->bclk)) {
700 		ret = PTR_ERR(priv->bclk);
701 		if (ret != -ENOENT) {
702 			if (ret != -EPROBE_DEFER)
703 				dev_err(&pdev->dev, "Can't get 'bus' clock\n");
704 			return ret;
705 		}
706 		priv->bclk = NULL;
707 	}
708 
709 	ret = stm32_adc_core_switches_probe(dev, priv);
710 	if (ret)
711 		return ret;
712 
713 	pm_runtime_get_noresume(dev);
714 	pm_runtime_set_active(dev);
715 	pm_runtime_set_autosuspend_delay(dev, STM32_ADC_CORE_SLEEP_DELAY_MS);
716 	pm_runtime_use_autosuspend(dev);
717 	pm_runtime_enable(dev);
718 
719 	ret = stm32_adc_core_hw_start(dev);
720 	if (ret)
721 		goto err_pm_stop;
722 
723 	ret = regulator_get_voltage(priv->vref);
724 	if (ret < 0) {
725 		dev_err(&pdev->dev, "vref get voltage failed, %d\n", ret);
726 		goto err_hw_stop;
727 	}
728 	priv->common.vref_mv = ret / 1000;
729 	dev_dbg(&pdev->dev, "vref+=%dmV\n", priv->common.vref_mv);
730 
731 	ret = of_property_read_u32(pdev->dev.of_node, "st,max-clk-rate-hz",
732 				   &max_rate);
733 	if (!ret)
734 		priv->max_clk_rate = min(max_rate, priv->cfg->max_clk_rate_hz);
735 	else
736 		priv->max_clk_rate = priv->cfg->max_clk_rate_hz;
737 
738 	ret = priv->cfg->clk_sel(pdev, priv);
739 	if (ret < 0)
740 		goto err_hw_stop;
741 
742 	ret = stm32_adc_irq_probe(pdev, priv);
743 	if (ret < 0)
744 		goto err_hw_stop;
745 
746 	ret = of_platform_populate(np, NULL, NULL, &pdev->dev);
747 	if (ret < 0) {
748 		dev_err(&pdev->dev, "failed to populate DT children\n");
749 		goto err_irq_remove;
750 	}
751 
752 	pm_runtime_mark_last_busy(dev);
753 	pm_runtime_put_autosuspend(dev);
754 
755 	return 0;
756 
757 err_irq_remove:
758 	stm32_adc_irq_remove(pdev, priv);
759 err_hw_stop:
760 	stm32_adc_core_hw_stop(dev);
761 err_pm_stop:
762 	pm_runtime_disable(dev);
763 	pm_runtime_set_suspended(dev);
764 	pm_runtime_put_noidle(dev);
765 
766 	return ret;
767 }
768 
769 static int stm32_adc_remove(struct platform_device *pdev)
770 {
771 	struct stm32_adc_common *common = platform_get_drvdata(pdev);
772 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
773 
774 	pm_runtime_get_sync(&pdev->dev);
775 	of_platform_depopulate(&pdev->dev);
776 	stm32_adc_irq_remove(pdev, priv);
777 	stm32_adc_core_hw_stop(&pdev->dev);
778 	pm_runtime_disable(&pdev->dev);
779 	pm_runtime_set_suspended(&pdev->dev);
780 	pm_runtime_put_noidle(&pdev->dev);
781 
782 	return 0;
783 }
784 
785 #if defined(CONFIG_PM)
786 static int stm32_adc_core_runtime_suspend(struct device *dev)
787 {
788 	stm32_adc_core_hw_stop(dev);
789 
790 	return 0;
791 }
792 
793 static int stm32_adc_core_runtime_resume(struct device *dev)
794 {
795 	return stm32_adc_core_hw_start(dev);
796 }
797 #endif
798 
799 static const struct dev_pm_ops stm32_adc_core_pm_ops = {
800 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
801 				pm_runtime_force_resume)
802 	SET_RUNTIME_PM_OPS(stm32_adc_core_runtime_suspend,
803 			   stm32_adc_core_runtime_resume,
804 			   NULL)
805 };
806 
807 static const struct stm32_adc_priv_cfg stm32f4_adc_priv_cfg = {
808 	.regs = &stm32f4_adc_common_regs,
809 	.clk_sel = stm32f4_adc_clk_sel,
810 	.max_clk_rate_hz = 36000000,
811 	.num_irqs = 1,
812 };
813 
814 static const struct stm32_adc_priv_cfg stm32h7_adc_priv_cfg = {
815 	.regs = &stm32h7_adc_common_regs,
816 	.clk_sel = stm32h7_adc_clk_sel,
817 	.max_clk_rate_hz = 36000000,
818 	.has_syscfg = HAS_VBOOSTER,
819 	.num_irqs = 1,
820 };
821 
822 static const struct stm32_adc_priv_cfg stm32mp1_adc_priv_cfg = {
823 	.regs = &stm32h7_adc_common_regs,
824 	.clk_sel = stm32h7_adc_clk_sel,
825 	.max_clk_rate_hz = 40000000,
826 	.has_syscfg = HAS_VBOOSTER | HAS_ANASWVDD,
827 	.num_irqs = 2,
828 };
829 
830 static const struct of_device_id stm32_adc_of_match[] = {
831 	{
832 		.compatible = "st,stm32f4-adc-core",
833 		.data = (void *)&stm32f4_adc_priv_cfg
834 	}, {
835 		.compatible = "st,stm32h7-adc-core",
836 		.data = (void *)&stm32h7_adc_priv_cfg
837 	}, {
838 		.compatible = "st,stm32mp1-adc-core",
839 		.data = (void *)&stm32mp1_adc_priv_cfg
840 	}, {
841 	},
842 };
843 MODULE_DEVICE_TABLE(of, stm32_adc_of_match);
844 
845 static struct platform_driver stm32_adc_driver = {
846 	.probe = stm32_adc_probe,
847 	.remove = stm32_adc_remove,
848 	.driver = {
849 		.name = "stm32-adc-core",
850 		.of_match_table = stm32_adc_of_match,
851 		.pm = &stm32_adc_core_pm_ops,
852 	},
853 };
854 module_platform_driver(stm32_adc_driver);
855 
856 MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
857 MODULE_DESCRIPTION("STMicroelectronics STM32 ADC core driver");
858 MODULE_LICENSE("GPL v2");
859 MODULE_ALIAS("platform:stm32-adc-core");
860