xref: /openbmc/linux/drivers/iio/adc/stm32-adc-core.c (revision 9008a676)
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  * @num_adcs:   maximum number of ADC instances in the common registers
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 	unsigned int num_irqs;
75 	unsigned int num_adcs;
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, duty;
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 		/* If duty is an error, kindly use at least /2 divider */
230 		duty = clk_get_scaled_duty_cycle(priv->aclk, 100);
231 		if (duty < 0)
232 			dev_warn(&pdev->dev, "adc clock duty: %d\n", duty);
233 
234 		for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
235 			ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
236 			presc = stm32h7_adc_ckmodes_spec[i].presc;
237 			div = stm32h7_adc_ckmodes_spec[i].div;
238 
239 			if (ckmode)
240 				continue;
241 
242 			/*
243 			 * For proper operation, clock duty cycle range is 49%
244 			 * to 51%. Apply at least /2 prescaler otherwise.
245 			 */
246 			if (div == 1 && (duty < 49 || duty > 51))
247 				continue;
248 
249 			if ((rate / div) <= priv->max_clk_rate)
250 				goto out;
251 		}
252 	}
253 
254 	/* Synchronous clock modes (e.g. ckmode is 1, 2 or 3) */
255 	rate = clk_get_rate(priv->bclk);
256 	if (!rate) {
257 		dev_err(&pdev->dev, "Invalid bus clock rate: 0\n");
258 		return -EINVAL;
259 	}
260 
261 	duty = clk_get_scaled_duty_cycle(priv->bclk, 100);
262 	if (duty < 0)
263 		dev_warn(&pdev->dev, "bus clock duty: %d\n", duty);
264 
265 	for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
266 		ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
267 		presc = stm32h7_adc_ckmodes_spec[i].presc;
268 		div = stm32h7_adc_ckmodes_spec[i].div;
269 
270 		if (!ckmode)
271 			continue;
272 
273 		if (div == 1 && (duty < 49 || duty > 51))
274 			continue;
275 
276 		if ((rate / div) <= priv->max_clk_rate)
277 			goto out;
278 	}
279 
280 	dev_err(&pdev->dev, "adc clk selection failed\n");
281 	return -EINVAL;
282 
283 out:
284 	/* rate used later by each ADC instance to control BOOST mode */
285 	priv->common.rate = rate / div;
286 
287 	/* Set common clock mode and prescaler */
288 	val = readl_relaxed(priv->common.base + STM32H7_ADC_CCR);
289 	val &= ~(STM32H7_CKMODE_MASK | STM32H7_PRESC_MASK);
290 	val |= ckmode << STM32H7_CKMODE_SHIFT;
291 	val |= presc << STM32H7_PRESC_SHIFT;
292 	writel_relaxed(val, priv->common.base + STM32H7_ADC_CCR);
293 
294 	dev_dbg(&pdev->dev, "Using %s clock/%d source at %ld kHz\n",
295 		ckmode ? "bus" : "adc", div, priv->common.rate / 1000);
296 
297 	return 0;
298 }
299 
300 /* STM32F4 common registers definitions */
301 static const struct stm32_adc_common_regs stm32f4_adc_common_regs = {
302 	.csr = STM32F4_ADC_CSR,
303 	.ccr = STM32F4_ADC_CCR,
304 	.eoc_msk = { STM32F4_EOC1, STM32F4_EOC2, STM32F4_EOC3},
305 	.ovr_msk = { STM32F4_OVR1, STM32F4_OVR2, STM32F4_OVR3},
306 	.ier = STM32F4_ADC_CR1,
307 	.eocie_msk = STM32F4_EOCIE,
308 };
309 
310 /* STM32H7 common registers definitions */
311 static const struct stm32_adc_common_regs stm32h7_adc_common_regs = {
312 	.csr = STM32H7_ADC_CSR,
313 	.ccr = STM32H7_ADC_CCR,
314 	.eoc_msk = { STM32H7_EOC_MST, STM32H7_EOC_SLV},
315 	.ovr_msk = { STM32H7_OVR_MST, STM32H7_OVR_SLV},
316 	.ier = STM32H7_ADC_IER,
317 	.eocie_msk = STM32H7_EOCIE,
318 };
319 
320 static const unsigned int stm32_adc_offset[STM32_ADC_MAX_ADCS] = {
321 	0, STM32_ADC_OFFSET, STM32_ADC_OFFSET * 2,
322 };
323 
324 static unsigned int stm32_adc_eoc_enabled(struct stm32_adc_priv *priv,
325 					  unsigned int adc)
326 {
327 	u32 ier, offset = stm32_adc_offset[adc];
328 
329 	ier = readl_relaxed(priv->common.base + offset + priv->cfg->regs->ier);
330 
331 	return ier & priv->cfg->regs->eocie_msk;
332 }
333 
334 /* ADC common interrupt for all instances */
335 static void stm32_adc_irq_handler(struct irq_desc *desc)
336 {
337 	struct stm32_adc_priv *priv = irq_desc_get_handler_data(desc);
338 	struct irq_chip *chip = irq_desc_get_chip(desc);
339 	int i;
340 	u32 status;
341 
342 	chained_irq_enter(chip, desc);
343 	status = readl_relaxed(priv->common.base + priv->cfg->regs->csr);
344 
345 	/*
346 	 * End of conversion may be handled by using IRQ or DMA. There may be a
347 	 * race here when two conversions complete at the same time on several
348 	 * ADCs. EOC may be read 'set' for several ADCs, with:
349 	 * - an ADC configured to use DMA (EOC triggers the DMA request, and
350 	 *   is then automatically cleared by DR read in hardware)
351 	 * - an ADC configured to use IRQs (EOCIE bit is set. The handler must
352 	 *   be called in this case)
353 	 * So both EOC status bit in CSR and EOCIE control bit must be checked
354 	 * before invoking the interrupt handler (e.g. call ISR only for
355 	 * IRQ-enabled ADCs).
356 	 */
357 	for (i = 0; i < priv->cfg->num_adcs; i++) {
358 		if ((status & priv->cfg->regs->eoc_msk[i] &&
359 		     stm32_adc_eoc_enabled(priv, i)) ||
360 		     (status & priv->cfg->regs->ovr_msk[i]))
361 			generic_handle_irq(irq_find_mapping(priv->domain, i));
362 	}
363 
364 	chained_irq_exit(chip, desc);
365 };
366 
367 static int stm32_adc_domain_map(struct irq_domain *d, unsigned int irq,
368 				irq_hw_number_t hwirq)
369 {
370 	irq_set_chip_data(irq, d->host_data);
371 	irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_level_irq);
372 
373 	return 0;
374 }
375 
376 static void stm32_adc_domain_unmap(struct irq_domain *d, unsigned int irq)
377 {
378 	irq_set_chip_and_handler(irq, NULL, NULL);
379 	irq_set_chip_data(irq, NULL);
380 }
381 
382 static const struct irq_domain_ops stm32_adc_domain_ops = {
383 	.map = stm32_adc_domain_map,
384 	.unmap  = stm32_adc_domain_unmap,
385 	.xlate = irq_domain_xlate_onecell,
386 };
387 
388 static int stm32_adc_irq_probe(struct platform_device *pdev,
389 			       struct stm32_adc_priv *priv)
390 {
391 	struct device_node *np = pdev->dev.of_node;
392 	unsigned int i;
393 
394 	/*
395 	 * Interrupt(s) must be provided, depending on the compatible:
396 	 * - stm32f4/h7 shares a common interrupt line.
397 	 * - stm32mp1, has one line per ADC
398 	 */
399 	for (i = 0; i < priv->cfg->num_irqs; i++) {
400 		priv->irq[i] = platform_get_irq(pdev, i);
401 		if (priv->irq[i] < 0)
402 			return priv->irq[i];
403 	}
404 
405 	priv->domain = irq_domain_add_simple(np, STM32_ADC_MAX_ADCS, 0,
406 					     &stm32_adc_domain_ops,
407 					     priv);
408 	if (!priv->domain) {
409 		dev_err(&pdev->dev, "Failed to add irq domain\n");
410 		return -ENOMEM;
411 	}
412 
413 	for (i = 0; i < priv->cfg->num_irqs; i++) {
414 		irq_set_chained_handler(priv->irq[i], stm32_adc_irq_handler);
415 		irq_set_handler_data(priv->irq[i], priv);
416 	}
417 
418 	return 0;
419 }
420 
421 static void stm32_adc_irq_remove(struct platform_device *pdev,
422 				 struct stm32_adc_priv *priv)
423 {
424 	int hwirq;
425 	unsigned int i;
426 
427 	for (hwirq = 0; hwirq < STM32_ADC_MAX_ADCS; hwirq++)
428 		irq_dispose_mapping(irq_find_mapping(priv->domain, hwirq));
429 	irq_domain_remove(priv->domain);
430 
431 	for (i = 0; i < priv->cfg->num_irqs; i++)
432 		irq_set_chained_handler(priv->irq[i], NULL);
433 }
434 
435 static int stm32_adc_core_switches_supply_en(struct stm32_adc_priv *priv,
436 					     struct device *dev)
437 {
438 	int ret;
439 
440 	/*
441 	 * On STM32H7 and STM32MP1, the ADC inputs are multiplexed with analog
442 	 * switches (via PCSEL) which have reduced performances when their
443 	 * supply is below 2.7V (vdda by default):
444 	 * - Voltage booster can be used, to get full ADC performances
445 	 *   (increases power consumption).
446 	 * - Vdd can be used to supply them, if above 2.7V (STM32MP1 only).
447 	 *
448 	 * Recommended settings for ANASWVDD and EN_BOOSTER:
449 	 * - vdda < 2.7V but vdd > 2.7V: ANASWVDD = 1, EN_BOOSTER = 0 (stm32mp1)
450 	 * - vdda < 2.7V and vdd < 2.7V: ANASWVDD = 0, EN_BOOSTER = 1
451 	 * - vdda >= 2.7V:               ANASWVDD = 0, EN_BOOSTER = 0 (default)
452 	 */
453 	if (priv->vdda_uv < 2700000) {
454 		if (priv->syscfg && priv->vdd_uv > 2700000) {
455 			ret = regulator_enable(priv->vdd);
456 			if (ret < 0) {
457 				dev_err(dev, "vdd enable failed %d\n", ret);
458 				return ret;
459 			}
460 
461 			ret = regmap_write(priv->syscfg,
462 					   STM32MP1_SYSCFG_PMCSETR,
463 					   STM32MP1_SYSCFG_ANASWVDD_MASK);
464 			if (ret < 0) {
465 				regulator_disable(priv->vdd);
466 				dev_err(dev, "vdd select failed, %d\n", ret);
467 				return ret;
468 			}
469 			dev_dbg(dev, "analog switches supplied by vdd\n");
470 
471 			return 0;
472 		}
473 
474 		if (priv->booster) {
475 			/*
476 			 * This is optional, as this is a trade-off between
477 			 * analog performance and power consumption.
478 			 */
479 			ret = regulator_enable(priv->booster);
480 			if (ret < 0) {
481 				dev_err(dev, "booster enable failed %d\n", ret);
482 				return ret;
483 			}
484 			dev_dbg(dev, "analog switches supplied by booster\n");
485 
486 			return 0;
487 		}
488 	}
489 
490 	/* Fallback using vdda (default), nothing to do */
491 	dev_dbg(dev, "analog switches supplied by vdda (%d uV)\n",
492 		priv->vdda_uv);
493 
494 	return 0;
495 }
496 
497 static void stm32_adc_core_switches_supply_dis(struct stm32_adc_priv *priv)
498 {
499 	if (priv->vdda_uv < 2700000) {
500 		if (priv->syscfg && priv->vdd_uv > 2700000) {
501 			regmap_write(priv->syscfg, STM32MP1_SYSCFG_PMCCLRR,
502 				     STM32MP1_SYSCFG_ANASWVDD_MASK);
503 			regulator_disable(priv->vdd);
504 			return;
505 		}
506 		if (priv->booster)
507 			regulator_disable(priv->booster);
508 	}
509 }
510 
511 static int stm32_adc_core_hw_start(struct device *dev)
512 {
513 	struct stm32_adc_common *common = dev_get_drvdata(dev);
514 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
515 	int ret;
516 
517 	ret = regulator_enable(priv->vdda);
518 	if (ret < 0) {
519 		dev_err(dev, "vdda enable failed %d\n", ret);
520 		return ret;
521 	}
522 
523 	ret = regulator_get_voltage(priv->vdda);
524 	if (ret < 0) {
525 		dev_err(dev, "vdda get voltage failed, %d\n", ret);
526 		goto err_vdda_disable;
527 	}
528 	priv->vdda_uv = ret;
529 
530 	ret = stm32_adc_core_switches_supply_en(priv, dev);
531 	if (ret < 0)
532 		goto err_vdda_disable;
533 
534 	ret = regulator_enable(priv->vref);
535 	if (ret < 0) {
536 		dev_err(dev, "vref enable failed\n");
537 		goto err_switches_dis;
538 	}
539 
540 	ret = clk_prepare_enable(priv->bclk);
541 	if (ret < 0) {
542 		dev_err(dev, "bus clk enable failed\n");
543 		goto err_regulator_disable;
544 	}
545 
546 	ret = clk_prepare_enable(priv->aclk);
547 	if (ret < 0) {
548 		dev_err(dev, "adc clk enable failed\n");
549 		goto err_bclk_disable;
550 	}
551 
552 	writel_relaxed(priv->ccr_bak, priv->common.base + priv->cfg->regs->ccr);
553 
554 	return 0;
555 
556 err_bclk_disable:
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 	clk_disable_unprepare(priv->aclk);
576 	clk_disable_unprepare(priv->bclk);
577 	regulator_disable(priv->vref);
578 	stm32_adc_core_switches_supply_dis(priv);
579 	regulator_disable(priv->vdda);
580 }
581 
582 static int stm32_adc_core_switches_probe(struct device *dev,
583 					 struct stm32_adc_priv *priv)
584 {
585 	struct device_node *np = dev->of_node;
586 	int ret;
587 
588 	/* Analog switches supply can be controlled by syscfg (optional) */
589 	priv->syscfg = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
590 	if (IS_ERR(priv->syscfg)) {
591 		ret = PTR_ERR(priv->syscfg);
592 		if (ret != -ENODEV)
593 			return dev_err_probe(dev, ret, "Can't probe syscfg\n");
594 
595 		priv->syscfg = NULL;
596 	}
597 
598 	/* Booster can be used to supply analog switches (optional) */
599 	if (priv->cfg->has_syscfg & HAS_VBOOSTER &&
600 	    of_property_read_bool(np, "booster-supply")) {
601 		priv->booster = devm_regulator_get_optional(dev, "booster");
602 		if (IS_ERR(priv->booster)) {
603 			ret = PTR_ERR(priv->booster);
604 			if (ret != -ENODEV)
605 				return dev_err_probe(dev, ret, "can't get booster\n");
606 
607 			priv->booster = NULL;
608 		}
609 	}
610 
611 	/* Vdd can be used to supply analog switches (optional) */
612 	if (priv->cfg->has_syscfg & HAS_ANASWVDD &&
613 	    of_property_read_bool(np, "vdd-supply")) {
614 		priv->vdd = devm_regulator_get_optional(dev, "vdd");
615 		if (IS_ERR(priv->vdd)) {
616 			ret = PTR_ERR(priv->vdd);
617 			if (ret != -ENODEV)
618 				return dev_err_probe(dev, ret, "can't get vdd\n");
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 	spin_lock_init(&priv->common.lock);
665 
666 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
667 	priv->common.base = devm_ioremap_resource(&pdev->dev, res);
668 	if (IS_ERR(priv->common.base))
669 		return PTR_ERR(priv->common.base);
670 	priv->common.phys_base = res->start;
671 
672 	priv->vdda = devm_regulator_get(&pdev->dev, "vdda");
673 	if (IS_ERR(priv->vdda))
674 		return dev_err_probe(&pdev->dev, PTR_ERR(priv->vdda),
675 				     "vdda get failed\n");
676 
677 	priv->vref = devm_regulator_get(&pdev->dev, "vref");
678 	if (IS_ERR(priv->vref))
679 		return dev_err_probe(&pdev->dev, PTR_ERR(priv->vref),
680 				     "vref get failed\n");
681 
682 	priv->aclk = devm_clk_get_optional(&pdev->dev, "adc");
683 	if (IS_ERR(priv->aclk))
684 		return dev_err_probe(&pdev->dev, PTR_ERR(priv->aclk),
685 				     "Can't get 'adc' clock\n");
686 
687 	priv->bclk = devm_clk_get_optional(&pdev->dev, "bus");
688 	if (IS_ERR(priv->bclk))
689 		return dev_err_probe(&pdev->dev, PTR_ERR(priv->bclk),
690 				     "Can't get 'bus' clock\n");
691 
692 	ret = stm32_adc_core_switches_probe(dev, priv);
693 	if (ret)
694 		return ret;
695 
696 	pm_runtime_get_noresume(dev);
697 	pm_runtime_set_active(dev);
698 	pm_runtime_set_autosuspend_delay(dev, STM32_ADC_CORE_SLEEP_DELAY_MS);
699 	pm_runtime_use_autosuspend(dev);
700 	pm_runtime_enable(dev);
701 
702 	ret = stm32_adc_core_hw_start(dev);
703 	if (ret)
704 		goto err_pm_stop;
705 
706 	ret = regulator_get_voltage(priv->vref);
707 	if (ret < 0) {
708 		dev_err(&pdev->dev, "vref get voltage failed, %d\n", ret);
709 		goto err_hw_stop;
710 	}
711 	priv->common.vref_mv = ret / 1000;
712 	dev_dbg(&pdev->dev, "vref+=%dmV\n", priv->common.vref_mv);
713 
714 	ret = of_property_read_u32(pdev->dev.of_node, "st,max-clk-rate-hz",
715 				   &max_rate);
716 	if (!ret)
717 		priv->max_clk_rate = min(max_rate, priv->cfg->max_clk_rate_hz);
718 	else
719 		priv->max_clk_rate = priv->cfg->max_clk_rate_hz;
720 
721 	ret = priv->cfg->clk_sel(pdev, priv);
722 	if (ret < 0)
723 		goto err_hw_stop;
724 
725 	ret = stm32_adc_irq_probe(pdev, priv);
726 	if (ret < 0)
727 		goto err_hw_stop;
728 
729 	ret = of_platform_populate(np, NULL, NULL, &pdev->dev);
730 	if (ret < 0) {
731 		dev_err(&pdev->dev, "failed to populate DT children\n");
732 		goto err_irq_remove;
733 	}
734 
735 	pm_runtime_mark_last_busy(dev);
736 	pm_runtime_put_autosuspend(dev);
737 
738 	return 0;
739 
740 err_irq_remove:
741 	stm32_adc_irq_remove(pdev, priv);
742 err_hw_stop:
743 	stm32_adc_core_hw_stop(dev);
744 err_pm_stop:
745 	pm_runtime_disable(dev);
746 	pm_runtime_set_suspended(dev);
747 	pm_runtime_put_noidle(dev);
748 
749 	return ret;
750 }
751 
752 static int stm32_adc_remove(struct platform_device *pdev)
753 {
754 	struct stm32_adc_common *common = platform_get_drvdata(pdev);
755 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
756 
757 	pm_runtime_get_sync(&pdev->dev);
758 	of_platform_depopulate(&pdev->dev);
759 	stm32_adc_irq_remove(pdev, priv);
760 	stm32_adc_core_hw_stop(&pdev->dev);
761 	pm_runtime_disable(&pdev->dev);
762 	pm_runtime_set_suspended(&pdev->dev);
763 	pm_runtime_put_noidle(&pdev->dev);
764 
765 	return 0;
766 }
767 
768 static int stm32_adc_core_runtime_suspend(struct device *dev)
769 {
770 	stm32_adc_core_hw_stop(dev);
771 
772 	return 0;
773 }
774 
775 static int stm32_adc_core_runtime_resume(struct device *dev)
776 {
777 	return stm32_adc_core_hw_start(dev);
778 }
779 
780 static int stm32_adc_core_runtime_idle(struct device *dev)
781 {
782 	pm_runtime_mark_last_busy(dev);
783 
784 	return 0;
785 }
786 
787 static DEFINE_RUNTIME_DEV_PM_OPS(stm32_adc_core_pm_ops,
788 				stm32_adc_core_runtime_suspend,
789 				stm32_adc_core_runtime_resume,
790 				stm32_adc_core_runtime_idle);
791 
792 static const struct stm32_adc_priv_cfg stm32f4_adc_priv_cfg = {
793 	.regs = &stm32f4_adc_common_regs,
794 	.clk_sel = stm32f4_adc_clk_sel,
795 	.max_clk_rate_hz = 36000000,
796 	.num_irqs = 1,
797 	.num_adcs = 3,
798 };
799 
800 static const struct stm32_adc_priv_cfg stm32h7_adc_priv_cfg = {
801 	.regs = &stm32h7_adc_common_regs,
802 	.clk_sel = stm32h7_adc_clk_sel,
803 	.max_clk_rate_hz = 36000000,
804 	.has_syscfg = HAS_VBOOSTER,
805 	.num_irqs = 1,
806 	.num_adcs = 2,
807 };
808 
809 static const struct stm32_adc_priv_cfg stm32mp1_adc_priv_cfg = {
810 	.regs = &stm32h7_adc_common_regs,
811 	.clk_sel = stm32h7_adc_clk_sel,
812 	.max_clk_rate_hz = 36000000,
813 	.has_syscfg = HAS_VBOOSTER | HAS_ANASWVDD,
814 	.num_irqs = 2,
815 	.num_adcs = 2,
816 };
817 
818 static const struct of_device_id stm32_adc_of_match[] = {
819 	{
820 		.compatible = "st,stm32f4-adc-core",
821 		.data = (void *)&stm32f4_adc_priv_cfg
822 	}, {
823 		.compatible = "st,stm32h7-adc-core",
824 		.data = (void *)&stm32h7_adc_priv_cfg
825 	}, {
826 		.compatible = "st,stm32mp1-adc-core",
827 		.data = (void *)&stm32mp1_adc_priv_cfg
828 	}, {
829 	},
830 };
831 MODULE_DEVICE_TABLE(of, stm32_adc_of_match);
832 
833 static struct platform_driver stm32_adc_driver = {
834 	.probe = stm32_adc_probe,
835 	.remove = stm32_adc_remove,
836 	.driver = {
837 		.name = "stm32-adc-core",
838 		.of_match_table = stm32_adc_of_match,
839 		.pm = pm_ptr(&stm32_adc_core_pm_ops),
840 	},
841 };
842 module_platform_driver(stm32_adc_driver);
843 
844 MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
845 MODULE_DESCRIPTION("STMicroelectronics STM32 ADC core driver");
846 MODULE_LICENSE("GPL v2");
847 MODULE_ALIAS("platform:stm32-adc-core");
848