xref: /openbmc/linux/drivers/iio/adc/stm32-adc-core.c (revision 27ab1c1c)
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  * @eoc_msk:    array of eoc (end of conversion flag) masks in csr for adc1..n
45  * @ovr_msk:    array of ovr (overrun flag) masks in csr for adc1..n
46  * @ier:	interrupt enable register offset for each adc
47  * @eocie_msk:	end of conversion interrupt enable mask in @ier
48  */
49 struct stm32_adc_common_regs {
50 	u32 csr;
51 	u32 ccr;
52 	u32 eoc_msk[STM32_ADC_MAX_ADCS];
53 	u32 ovr_msk[STM32_ADC_MAX_ADCS];
54 	u32 ier;
55 	u32 eocie_msk;
56 };
57 
58 struct stm32_adc_priv;
59 
60 /**
61  * struct stm32_adc_priv_cfg - stm32 core compatible configuration data
62  * @regs:	common registers for all instances
63  * @clk_sel:	clock selection routine
64  * @max_clk_rate_hz: maximum analog clock rate (Hz, from datasheet)
65  * @has_syscfg: SYSCFG capability flags
66  * @num_irqs:	number of interrupt lines
67  */
68 struct stm32_adc_priv_cfg {
69 	const struct stm32_adc_common_regs *regs;
70 	int (*clk_sel)(struct platform_device *, struct stm32_adc_priv *);
71 	u32 max_clk_rate_hz;
72 	unsigned int has_syscfg;
73 	unsigned int num_irqs;
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, duty;
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 		/* If duty is an error, kindly use at least /2 divider */
228 		duty = clk_get_scaled_duty_cycle(priv->aclk, 100);
229 		if (duty < 0)
230 			dev_warn(&pdev->dev, "adc clock duty: %d\n", duty);
231 
232 		for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
233 			ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
234 			presc = stm32h7_adc_ckmodes_spec[i].presc;
235 			div = stm32h7_adc_ckmodes_spec[i].div;
236 
237 			if (ckmode)
238 				continue;
239 
240 			/*
241 			 * For proper operation, clock duty cycle range is 49%
242 			 * to 51%. Apply at least /2 prescaler otherwise.
243 			 */
244 			if (div == 1 && (duty < 49 || duty > 51))
245 				continue;
246 
247 			if ((rate / div) <= priv->max_clk_rate)
248 				goto out;
249 		}
250 	}
251 
252 	/* Synchronous clock modes (e.g. ckmode is 1, 2 or 3) */
253 	rate = clk_get_rate(priv->bclk);
254 	if (!rate) {
255 		dev_err(&pdev->dev, "Invalid bus clock rate: 0\n");
256 		return -EINVAL;
257 	}
258 
259 	duty = clk_get_scaled_duty_cycle(priv->bclk, 100);
260 	if (duty < 0)
261 		dev_warn(&pdev->dev, "bus clock duty: %d\n", duty);
262 
263 	for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
264 		ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
265 		presc = stm32h7_adc_ckmodes_spec[i].presc;
266 		div = stm32h7_adc_ckmodes_spec[i].div;
267 
268 		if (!ckmode)
269 			continue;
270 
271 		if (div == 1 && (duty < 49 || duty > 51))
272 			continue;
273 
274 		if ((rate / div) <= priv->max_clk_rate)
275 			goto out;
276 	}
277 
278 	dev_err(&pdev->dev, "adc clk selection failed\n");
279 	return -EINVAL;
280 
281 out:
282 	/* rate used later by each ADC instance to control BOOST mode */
283 	priv->common.rate = rate / div;
284 
285 	/* Set common clock mode and prescaler */
286 	val = readl_relaxed(priv->common.base + STM32H7_ADC_CCR);
287 	val &= ~(STM32H7_CKMODE_MASK | STM32H7_PRESC_MASK);
288 	val |= ckmode << STM32H7_CKMODE_SHIFT;
289 	val |= presc << STM32H7_PRESC_SHIFT;
290 	writel_relaxed(val, priv->common.base + STM32H7_ADC_CCR);
291 
292 	dev_dbg(&pdev->dev, "Using %s clock/%d source at %ld kHz\n",
293 		ckmode ? "bus" : "adc", div, priv->common.rate / 1000);
294 
295 	return 0;
296 }
297 
298 /* STM32F4 common registers definitions */
299 static const struct stm32_adc_common_regs stm32f4_adc_common_regs = {
300 	.csr = STM32F4_ADC_CSR,
301 	.ccr = STM32F4_ADC_CCR,
302 	.eoc_msk = { STM32F4_EOC1, STM32F4_EOC2, STM32F4_EOC3},
303 	.ovr_msk = { STM32F4_OVR1, STM32F4_OVR2, STM32F4_OVR3},
304 	.ier = STM32F4_ADC_CR1,
305 	.eocie_msk = STM32F4_EOCIE,
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 	.eoc_msk = { STM32H7_EOC_MST, STM32H7_EOC_SLV},
313 	.ovr_msk = { STM32H7_OVR_MST, STM32H7_OVR_SLV},
314 	.ier = STM32H7_ADC_IER,
315 	.eocie_msk = STM32H7_EOCIE,
316 };
317 
318 static const unsigned int stm32_adc_offset[STM32_ADC_MAX_ADCS] = {
319 	0, STM32_ADC_OFFSET, STM32_ADC_OFFSET * 2,
320 };
321 
322 static unsigned int stm32_adc_eoc_enabled(struct stm32_adc_priv *priv,
323 					  unsigned int adc)
324 {
325 	u32 ier, offset = stm32_adc_offset[adc];
326 
327 	ier = readl_relaxed(priv->common.base + offset + priv->cfg->regs->ier);
328 
329 	return ier & priv->cfg->regs->eocie_msk;
330 }
331 
332 /* ADC common interrupt for all instances */
333 static void stm32_adc_irq_handler(struct irq_desc *desc)
334 {
335 	struct stm32_adc_priv *priv = irq_desc_get_handler_data(desc);
336 	struct irq_chip *chip = irq_desc_get_chip(desc);
337 	int i;
338 	u32 status;
339 
340 	chained_irq_enter(chip, desc);
341 	status = readl_relaxed(priv->common.base + priv->cfg->regs->csr);
342 
343 	/*
344 	 * End of conversion may be handled by using IRQ or DMA. There may be a
345 	 * race here when two conversions complete at the same time on several
346 	 * ADCs. EOC may be read 'set' for several ADCs, with:
347 	 * - an ADC configured to use DMA (EOC triggers the DMA request, and
348 	 *   is then automatically cleared by DR read in hardware)
349 	 * - an ADC configured to use IRQs (EOCIE bit is set. The handler must
350 	 *   be called in this case)
351 	 * So both EOC status bit in CSR and EOCIE control bit must be checked
352 	 * before invoking the interrupt handler (e.g. call ISR only for
353 	 * IRQ-enabled ADCs).
354 	 */
355 	for (i = 0; i < priv->cfg->num_irqs; i++) {
356 		if ((status & priv->cfg->regs->eoc_msk[i] &&
357 		     stm32_adc_eoc_enabled(priv, i)) ||
358 		     (status & priv->cfg->regs->ovr_msk[i]))
359 			generic_handle_irq(irq_find_mapping(priv->domain, i));
360 	}
361 
362 	chained_irq_exit(chip, desc);
363 };
364 
365 static int stm32_adc_domain_map(struct irq_domain *d, unsigned int irq,
366 				irq_hw_number_t hwirq)
367 {
368 	irq_set_chip_data(irq, d->host_data);
369 	irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_level_irq);
370 
371 	return 0;
372 }
373 
374 static void stm32_adc_domain_unmap(struct irq_domain *d, unsigned int irq)
375 {
376 	irq_set_chip_and_handler(irq, NULL, NULL);
377 	irq_set_chip_data(irq, NULL);
378 }
379 
380 static const struct irq_domain_ops stm32_adc_domain_ops = {
381 	.map = stm32_adc_domain_map,
382 	.unmap  = stm32_adc_domain_unmap,
383 	.xlate = irq_domain_xlate_onecell,
384 };
385 
386 static int stm32_adc_irq_probe(struct platform_device *pdev,
387 			       struct stm32_adc_priv *priv)
388 {
389 	struct device_node *np = pdev->dev.of_node;
390 	unsigned int i;
391 
392 	/*
393 	 * Interrupt(s) must be provided, depending on the compatible:
394 	 * - stm32f4/h7 shares a common interrupt line.
395 	 * - stm32mp1, has one line per ADC
396 	 */
397 	for (i = 0; i < priv->cfg->num_irqs; i++) {
398 		priv->irq[i] = platform_get_irq(pdev, i);
399 		if (priv->irq[i] < 0)
400 			return priv->irq[i];
401 	}
402 
403 	priv->domain = irq_domain_add_simple(np, STM32_ADC_MAX_ADCS, 0,
404 					     &stm32_adc_domain_ops,
405 					     priv);
406 	if (!priv->domain) {
407 		dev_err(&pdev->dev, "Failed to add irq domain\n");
408 		return -ENOMEM;
409 	}
410 
411 	for (i = 0; i < priv->cfg->num_irqs; i++) {
412 		irq_set_chained_handler(priv->irq[i], stm32_adc_irq_handler);
413 		irq_set_handler_data(priv->irq[i], priv);
414 	}
415 
416 	return 0;
417 }
418 
419 static void stm32_adc_irq_remove(struct platform_device *pdev,
420 				 struct stm32_adc_priv *priv)
421 {
422 	int hwirq;
423 	unsigned int i;
424 
425 	for (hwirq = 0; hwirq < STM32_ADC_MAX_ADCS; hwirq++)
426 		irq_dispose_mapping(irq_find_mapping(priv->domain, hwirq));
427 	irq_domain_remove(priv->domain);
428 
429 	for (i = 0; i < priv->cfg->num_irqs; i++)
430 		irq_set_chained_handler(priv->irq[i], NULL);
431 }
432 
433 static int stm32_adc_core_switches_supply_en(struct stm32_adc_priv *priv,
434 					     struct device *dev)
435 {
436 	int ret;
437 
438 	/*
439 	 * On STM32H7 and STM32MP1, the ADC inputs are multiplexed with analog
440 	 * switches (via PCSEL) which have reduced performances when their
441 	 * supply is below 2.7V (vdda by default):
442 	 * - Voltage booster can be used, to get full ADC performances
443 	 *   (increases power consumption).
444 	 * - Vdd can be used to supply them, if above 2.7V (STM32MP1 only).
445 	 *
446 	 * Recommended settings for ANASWVDD and EN_BOOSTER:
447 	 * - vdda < 2.7V but vdd > 2.7V: ANASWVDD = 1, EN_BOOSTER = 0 (stm32mp1)
448 	 * - vdda < 2.7V and vdd < 2.7V: ANASWVDD = 0, EN_BOOSTER = 1
449 	 * - vdda >= 2.7V:               ANASWVDD = 0, EN_BOOSTER = 0 (default)
450 	 */
451 	if (priv->vdda_uv < 2700000) {
452 		if (priv->syscfg && priv->vdd_uv > 2700000) {
453 			ret = regulator_enable(priv->vdd);
454 			if (ret < 0) {
455 				dev_err(dev, "vdd enable failed %d\n", ret);
456 				return ret;
457 			}
458 
459 			ret = regmap_write(priv->syscfg,
460 					   STM32MP1_SYSCFG_PMCSETR,
461 					   STM32MP1_SYSCFG_ANASWVDD_MASK);
462 			if (ret < 0) {
463 				regulator_disable(priv->vdd);
464 				dev_err(dev, "vdd select failed, %d\n", ret);
465 				return ret;
466 			}
467 			dev_dbg(dev, "analog switches supplied by vdd\n");
468 
469 			return 0;
470 		}
471 
472 		if (priv->booster) {
473 			/*
474 			 * This is optional, as this is a trade-off between
475 			 * analog performance and power consumption.
476 			 */
477 			ret = regulator_enable(priv->booster);
478 			if (ret < 0) {
479 				dev_err(dev, "booster enable failed %d\n", ret);
480 				return ret;
481 			}
482 			dev_dbg(dev, "analog switches supplied by booster\n");
483 
484 			return 0;
485 		}
486 	}
487 
488 	/* Fallback using vdda (default), nothing to do */
489 	dev_dbg(dev, "analog switches supplied by vdda (%d uV)\n",
490 		priv->vdda_uv);
491 
492 	return 0;
493 }
494 
495 static void stm32_adc_core_switches_supply_dis(struct stm32_adc_priv *priv)
496 {
497 	if (priv->vdda_uv < 2700000) {
498 		if (priv->syscfg && priv->vdd_uv > 2700000) {
499 			regmap_write(priv->syscfg, STM32MP1_SYSCFG_PMCCLRR,
500 				     STM32MP1_SYSCFG_ANASWVDD_MASK);
501 			regulator_disable(priv->vdd);
502 			return;
503 		}
504 		if (priv->booster)
505 			regulator_disable(priv->booster);
506 	}
507 }
508 
509 static int stm32_adc_core_hw_start(struct device *dev)
510 {
511 	struct stm32_adc_common *common = dev_get_drvdata(dev);
512 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
513 	int ret;
514 
515 	ret = regulator_enable(priv->vdda);
516 	if (ret < 0) {
517 		dev_err(dev, "vdda enable failed %d\n", ret);
518 		return ret;
519 	}
520 
521 	ret = regulator_get_voltage(priv->vdda);
522 	if (ret < 0) {
523 		dev_err(dev, "vdda get voltage failed, %d\n", ret);
524 		goto err_vdda_disable;
525 	}
526 	priv->vdda_uv = ret;
527 
528 	ret = stm32_adc_core_switches_supply_en(priv, dev);
529 	if (ret < 0)
530 		goto err_vdda_disable;
531 
532 	ret = regulator_enable(priv->vref);
533 	if (ret < 0) {
534 		dev_err(dev, "vref enable failed\n");
535 		goto err_switches_dis;
536 	}
537 
538 	if (priv->bclk) {
539 		ret = clk_prepare_enable(priv->bclk);
540 		if (ret < 0) {
541 			dev_err(dev, "bus clk enable failed\n");
542 			goto err_regulator_disable;
543 		}
544 	}
545 
546 	if (priv->aclk) {
547 		ret = clk_prepare_enable(priv->aclk);
548 		if (ret < 0) {
549 			dev_err(dev, "adc clk enable failed\n");
550 			goto err_bclk_disable;
551 		}
552 	}
553 
554 	writel_relaxed(priv->ccr_bak, priv->common.base + priv->cfg->regs->ccr);
555 
556 	return 0;
557 
558 err_bclk_disable:
559 	if (priv->bclk)
560 		clk_disable_unprepare(priv->bclk);
561 err_regulator_disable:
562 	regulator_disable(priv->vref);
563 err_switches_dis:
564 	stm32_adc_core_switches_supply_dis(priv);
565 err_vdda_disable:
566 	regulator_disable(priv->vdda);
567 
568 	return ret;
569 }
570 
571 static void stm32_adc_core_hw_stop(struct device *dev)
572 {
573 	struct stm32_adc_common *common = dev_get_drvdata(dev);
574 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
575 
576 	/* Backup CCR that may be lost (depends on power state to achieve) */
577 	priv->ccr_bak = readl_relaxed(priv->common.base + priv->cfg->regs->ccr);
578 	if (priv->aclk)
579 		clk_disable_unprepare(priv->aclk);
580 	if (priv->bclk)
581 		clk_disable_unprepare(priv->bclk);
582 	regulator_disable(priv->vref);
583 	stm32_adc_core_switches_supply_dis(priv);
584 	regulator_disable(priv->vdda);
585 }
586 
587 static int stm32_adc_core_switches_probe(struct device *dev,
588 					 struct stm32_adc_priv *priv)
589 {
590 	struct device_node *np = dev->of_node;
591 	int ret;
592 
593 	/* Analog switches supply can be controlled by syscfg (optional) */
594 	priv->syscfg = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
595 	if (IS_ERR(priv->syscfg)) {
596 		ret = PTR_ERR(priv->syscfg);
597 		if (ret != -ENODEV)
598 			return dev_err_probe(dev, ret, "Can't probe syscfg\n");
599 
600 		priv->syscfg = NULL;
601 	}
602 
603 	/* Booster can be used to supply analog switches (optional) */
604 	if (priv->cfg->has_syscfg & HAS_VBOOSTER &&
605 	    of_property_read_bool(np, "booster-supply")) {
606 		priv->booster = devm_regulator_get_optional(dev, "booster");
607 		if (IS_ERR(priv->booster)) {
608 			ret = PTR_ERR(priv->booster);
609 			if (ret != -ENODEV)
610 				return dev_err_probe(dev, ret, "can't get booster\n");
611 
612 			priv->booster = NULL;
613 		}
614 	}
615 
616 	/* Vdd can be used to supply analog switches (optional) */
617 	if (priv->cfg->has_syscfg & HAS_ANASWVDD &&
618 	    of_property_read_bool(np, "vdd-supply")) {
619 		priv->vdd = devm_regulator_get_optional(dev, "vdd");
620 		if (IS_ERR(priv->vdd)) {
621 			ret = PTR_ERR(priv->vdd);
622 			if (ret != -ENODEV)
623 				return dev_err_probe(dev, ret, "can't get vdd\n");
624 
625 			priv->vdd = NULL;
626 		}
627 	}
628 
629 	if (priv->vdd) {
630 		ret = regulator_enable(priv->vdd);
631 		if (ret < 0) {
632 			dev_err(dev, "vdd enable failed %d\n", ret);
633 			return ret;
634 		}
635 
636 		ret = regulator_get_voltage(priv->vdd);
637 		if (ret < 0) {
638 			dev_err(dev, "vdd get voltage failed %d\n", ret);
639 			regulator_disable(priv->vdd);
640 			return ret;
641 		}
642 		priv->vdd_uv = ret;
643 
644 		regulator_disable(priv->vdd);
645 	}
646 
647 	return 0;
648 }
649 
650 static int stm32_adc_probe(struct platform_device *pdev)
651 {
652 	struct stm32_adc_priv *priv;
653 	struct device *dev = &pdev->dev;
654 	struct device_node *np = pdev->dev.of_node;
655 	struct resource *res;
656 	u32 max_rate;
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 		return dev_err_probe(&pdev->dev, PTR_ERR(priv->vdda),
679 				     "vdda get failed\n");
680 
681 	priv->vref = devm_regulator_get(&pdev->dev, "vref");
682 	if (IS_ERR(priv->vref))
683 		return dev_err_probe(&pdev->dev, PTR_ERR(priv->vref),
684 				     "vref get failed\n");
685 
686 	priv->aclk = devm_clk_get_optional(&pdev->dev, "adc");
687 	if (IS_ERR(priv->aclk))
688 		return dev_err_probe(&pdev->dev, PTR_ERR(priv->aclk),
689 				     "Can't get 'adc' clock\n");
690 
691 	priv->bclk = devm_clk_get_optional(&pdev->dev, "bus");
692 	if (IS_ERR(priv->bclk))
693 		return dev_err_probe(&pdev->dev, PTR_ERR(priv->bclk),
694 				     "Can't get 'bus' clock\n");
695 
696 	ret = stm32_adc_core_switches_probe(dev, priv);
697 	if (ret)
698 		return ret;
699 
700 	pm_runtime_get_noresume(dev);
701 	pm_runtime_set_active(dev);
702 	pm_runtime_set_autosuspend_delay(dev, STM32_ADC_CORE_SLEEP_DELAY_MS);
703 	pm_runtime_use_autosuspend(dev);
704 	pm_runtime_enable(dev);
705 
706 	ret = stm32_adc_core_hw_start(dev);
707 	if (ret)
708 		goto err_pm_stop;
709 
710 	ret = regulator_get_voltage(priv->vref);
711 	if (ret < 0) {
712 		dev_err(&pdev->dev, "vref get voltage failed, %d\n", ret);
713 		goto err_hw_stop;
714 	}
715 	priv->common.vref_mv = ret / 1000;
716 	dev_dbg(&pdev->dev, "vref+=%dmV\n", priv->common.vref_mv);
717 
718 	ret = of_property_read_u32(pdev->dev.of_node, "st,max-clk-rate-hz",
719 				   &max_rate);
720 	if (!ret)
721 		priv->max_clk_rate = min(max_rate, priv->cfg->max_clk_rate_hz);
722 	else
723 		priv->max_clk_rate = priv->cfg->max_clk_rate_hz;
724 
725 	ret = priv->cfg->clk_sel(pdev, priv);
726 	if (ret < 0)
727 		goto err_hw_stop;
728 
729 	ret = stm32_adc_irq_probe(pdev, priv);
730 	if (ret < 0)
731 		goto err_hw_stop;
732 
733 	ret = of_platform_populate(np, NULL, NULL, &pdev->dev);
734 	if (ret < 0) {
735 		dev_err(&pdev->dev, "failed to populate DT children\n");
736 		goto err_irq_remove;
737 	}
738 
739 	pm_runtime_mark_last_busy(dev);
740 	pm_runtime_put_autosuspend(dev);
741 
742 	return 0;
743 
744 err_irq_remove:
745 	stm32_adc_irq_remove(pdev, priv);
746 err_hw_stop:
747 	stm32_adc_core_hw_stop(dev);
748 err_pm_stop:
749 	pm_runtime_disable(dev);
750 	pm_runtime_set_suspended(dev);
751 	pm_runtime_put_noidle(dev);
752 
753 	return ret;
754 }
755 
756 static int stm32_adc_remove(struct platform_device *pdev)
757 {
758 	struct stm32_adc_common *common = platform_get_drvdata(pdev);
759 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
760 
761 	pm_runtime_get_sync(&pdev->dev);
762 	of_platform_depopulate(&pdev->dev);
763 	stm32_adc_irq_remove(pdev, priv);
764 	stm32_adc_core_hw_stop(&pdev->dev);
765 	pm_runtime_disable(&pdev->dev);
766 	pm_runtime_set_suspended(&pdev->dev);
767 	pm_runtime_put_noidle(&pdev->dev);
768 
769 	return 0;
770 }
771 
772 #if defined(CONFIG_PM)
773 static int stm32_adc_core_runtime_suspend(struct device *dev)
774 {
775 	stm32_adc_core_hw_stop(dev);
776 
777 	return 0;
778 }
779 
780 static int stm32_adc_core_runtime_resume(struct device *dev)
781 {
782 	return stm32_adc_core_hw_start(dev);
783 }
784 
785 static int stm32_adc_core_runtime_idle(struct device *dev)
786 {
787 	pm_runtime_mark_last_busy(dev);
788 
789 	return 0;
790 }
791 #endif
792 
793 static const struct dev_pm_ops stm32_adc_core_pm_ops = {
794 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
795 				pm_runtime_force_resume)
796 	SET_RUNTIME_PM_OPS(stm32_adc_core_runtime_suspend,
797 			   stm32_adc_core_runtime_resume,
798 			   stm32_adc_core_runtime_idle)
799 };
800 
801 static const struct stm32_adc_priv_cfg stm32f4_adc_priv_cfg = {
802 	.regs = &stm32f4_adc_common_regs,
803 	.clk_sel = stm32f4_adc_clk_sel,
804 	.max_clk_rate_hz = 36000000,
805 	.num_irqs = 1,
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 	.num_irqs = 1,
814 };
815 
816 static const struct stm32_adc_priv_cfg stm32mp1_adc_priv_cfg = {
817 	.regs = &stm32h7_adc_common_regs,
818 	.clk_sel = stm32h7_adc_clk_sel,
819 	.max_clk_rate_hz = 40000000,
820 	.has_syscfg = HAS_VBOOSTER | HAS_ANASWVDD,
821 	.num_irqs = 2,
822 };
823 
824 static const struct of_device_id stm32_adc_of_match[] = {
825 	{
826 		.compatible = "st,stm32f4-adc-core",
827 		.data = (void *)&stm32f4_adc_priv_cfg
828 	}, {
829 		.compatible = "st,stm32h7-adc-core",
830 		.data = (void *)&stm32h7_adc_priv_cfg
831 	}, {
832 		.compatible = "st,stm32mp1-adc-core",
833 		.data = (void *)&stm32mp1_adc_priv_cfg
834 	}, {
835 	},
836 };
837 MODULE_DEVICE_TABLE(of, stm32_adc_of_match);
838 
839 static struct platform_driver stm32_adc_driver = {
840 	.probe = stm32_adc_probe,
841 	.remove = stm32_adc_remove,
842 	.driver = {
843 		.name = "stm32-adc-core",
844 		.of_match_table = stm32_adc_of_match,
845 		.pm = &stm32_adc_core_pm_ops,
846 	},
847 };
848 module_platform_driver(stm32_adc_driver);
849 
850 MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
851 MODULE_DESCRIPTION("STMicroelectronics STM32 ADC core driver");
852 MODULE_LICENSE("GPL v2");
853 MODULE_ALIAS("platform:stm32-adc-core");
854