xref: /openbmc/linux/drivers/iio/adc/stm32-adc-core.c (revision 7587cdef)
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/bitfield.h>
13 #include <linux/clk.h>
14 #include <linux/interrupt.h>
15 #include <linux/irqchip/chained_irq.h>
16 #include <linux/irqdesc.h>
17 #include <linux/irqdomain.h>
18 #include <linux/mfd/syscon.h>
19 #include <linux/module.h>
20 #include <linux/of_device.h>
21 #include <linux/pm_runtime.h>
22 #include <linux/regmap.h>
23 #include <linux/regulator/consumer.h>
24 #include <linux/slab.h>
25 
26 #include "stm32-adc-core.h"
27 
28 #define STM32_ADC_CORE_SLEEP_DELAY_MS	2000
29 
30 /* SYSCFG registers */
31 #define STM32MP1_SYSCFG_PMCSETR		0x04
32 #define STM32MP1_SYSCFG_PMCCLRR		0x44
33 
34 /* SYSCFG bit fields */
35 #define STM32MP1_SYSCFG_ANASWVDD_MASK	BIT(9)
36 
37 /* SYSCFG capability flags */
38 #define HAS_VBOOSTER		BIT(0)
39 #define HAS_ANASWVDD		BIT(1)
40 
41 /**
42  * struct stm32_adc_common_regs - stm32 common registers
43  * @csr:	common status register offset
44  * @ccr:	common control register offset
45  * @eoc_msk:    array of eoc (end of conversion flag) masks in csr for adc1..n
46  * @ovr_msk:    array of ovr (overrun flag) masks in csr for adc1..n
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 eoc_msk[STM32_ADC_MAX_ADCS];
54 	u32 ovr_msk[STM32_ADC_MAX_ADCS];
55 	u32 ier;
56 	u32 eocie_msk;
57 };
58 
59 struct stm32_adc_priv;
60 
61 /**
62  * struct stm32_adc_priv_cfg - stm32 core compatible configuration data
63  * @regs:	common registers for all instances
64  * @clk_sel:	clock selection routine
65  * @max_clk_rate_hz: maximum analog clock rate (Hz, from datasheet)
66  * @ipid:	adc identification number
67  * @has_syscfg: SYSCFG capability flags
68  * @num_irqs:	number of interrupt lines
69  * @num_adcs:   maximum number of ADC instances in the common registers
70  */
71 struct stm32_adc_priv_cfg {
72 	const struct stm32_adc_common_regs *regs;
73 	int (*clk_sel)(struct platform_device *, struct stm32_adc_priv *);
74 	u32 max_clk_rate_hz;
75 	u32 ipid;
76 	unsigned int has_syscfg;
77 	unsigned int num_irqs;
78 	unsigned int num_adcs;
79 };
80 
81 /**
82  * struct stm32_adc_priv - stm32 ADC core private data
83  * @irq:		irq(s) for ADC block
84  * @nb_adc_max:		actual maximum number of instance per ADC block
85  * @domain:		irq domain reference
86  * @aclk:		clock reference for the analog circuitry
87  * @bclk:		bus clock common for all ADCs, depends on part used
88  * @max_clk_rate:	desired maximum clock rate
89  * @booster:		booster supply reference
90  * @vdd:		vdd supply reference
91  * @vdda:		vdda analog supply reference
92  * @vref:		regulator reference
93  * @vdd_uv:		vdd supply voltage (microvolts)
94  * @vdda_uv:		vdda supply voltage (microvolts)
95  * @cfg:		compatible configuration data
96  * @common:		common data for all ADC instances
97  * @ccr_bak:		backup CCR in low power mode
98  * @syscfg:		reference to syscon, system control registers
99  */
100 struct stm32_adc_priv {
101 	int				irq[STM32_ADC_MAX_ADCS];
102 	unsigned int			nb_adc_max;
103 	struct irq_domain		*domain;
104 	struct clk			*aclk;
105 	struct clk			*bclk;
106 	u32				max_clk_rate;
107 	struct regulator		*booster;
108 	struct regulator		*vdd;
109 	struct regulator		*vdda;
110 	struct regulator		*vref;
111 	int				vdd_uv;
112 	int				vdda_uv;
113 	const struct stm32_adc_priv_cfg	*cfg;
114 	struct stm32_adc_common		common;
115 	u32				ccr_bak;
116 	struct regmap			*syscfg;
117 };
118 
119 static struct stm32_adc_priv *to_stm32_adc_priv(struct stm32_adc_common *com)
120 {
121 	return container_of(com, struct stm32_adc_priv, common);
122 }
123 
124 /* STM32F4 ADC internal common clock prescaler division ratios */
125 static int stm32f4_pclk_div[] = {2, 4, 6, 8};
126 
127 /**
128  * stm32f4_adc_clk_sel() - Select stm32f4 ADC common clock prescaler
129  * @pdev: platform device
130  * @priv: stm32 ADC core private data
131  * Select clock prescaler used for analog conversions, before using ADC.
132  */
133 static int stm32f4_adc_clk_sel(struct platform_device *pdev,
134 			       struct stm32_adc_priv *priv)
135 {
136 	unsigned long rate;
137 	u32 val;
138 	int i;
139 
140 	/* stm32f4 has one clk input for analog (mandatory), enforce it here */
141 	if (!priv->aclk) {
142 		dev_err(&pdev->dev, "No 'adc' clock found\n");
143 		return -ENOENT;
144 	}
145 
146 	rate = clk_get_rate(priv->aclk);
147 	if (!rate) {
148 		dev_err(&pdev->dev, "Invalid clock rate: 0\n");
149 		return -EINVAL;
150 	}
151 
152 	for (i = 0; i < ARRAY_SIZE(stm32f4_pclk_div); i++) {
153 		if ((rate / stm32f4_pclk_div[i]) <= priv->max_clk_rate)
154 			break;
155 	}
156 	if (i >= ARRAY_SIZE(stm32f4_pclk_div)) {
157 		dev_err(&pdev->dev, "adc clk selection failed\n");
158 		return -EINVAL;
159 	}
160 
161 	priv->common.rate = rate / stm32f4_pclk_div[i];
162 	val = readl_relaxed(priv->common.base + STM32F4_ADC_CCR);
163 	val &= ~STM32F4_ADC_ADCPRE_MASK;
164 	val |= i << STM32F4_ADC_ADCPRE_SHIFT;
165 	writel_relaxed(val, priv->common.base + STM32F4_ADC_CCR);
166 
167 	dev_dbg(&pdev->dev, "Using analog clock source at %ld kHz\n",
168 		priv->common.rate / 1000);
169 
170 	return 0;
171 }
172 
173 /**
174  * struct stm32h7_adc_ck_spec - specification for stm32h7 adc clock
175  * @ckmode: ADC clock mode, Async or sync with prescaler.
176  * @presc: prescaler bitfield for async clock mode
177  * @div: prescaler division ratio
178  */
179 struct stm32h7_adc_ck_spec {
180 	u32 ckmode;
181 	u32 presc;
182 	int div;
183 };
184 
185 static const struct stm32h7_adc_ck_spec stm32h7_adc_ckmodes_spec[] = {
186 	/* 00: CK_ADC[1..3]: Asynchronous clock modes */
187 	{ 0, 0, 1 },
188 	{ 0, 1, 2 },
189 	{ 0, 2, 4 },
190 	{ 0, 3, 6 },
191 	{ 0, 4, 8 },
192 	{ 0, 5, 10 },
193 	{ 0, 6, 12 },
194 	{ 0, 7, 16 },
195 	{ 0, 8, 32 },
196 	{ 0, 9, 64 },
197 	{ 0, 10, 128 },
198 	{ 0, 11, 256 },
199 	/* HCLK used: Synchronous clock modes (1, 2 or 4 prescaler) */
200 	{ 1, 0, 1 },
201 	{ 2, 0, 2 },
202 	{ 3, 0, 4 },
203 };
204 
205 static int stm32h7_adc_clk_sel(struct platform_device *pdev,
206 			       struct stm32_adc_priv *priv)
207 {
208 	u32 ckmode, presc, val;
209 	unsigned long rate;
210 	int i, div, duty;
211 
212 	/* stm32h7 bus clock is common for all ADC instances (mandatory) */
213 	if (!priv->bclk) {
214 		dev_err(&pdev->dev, "No 'bus' clock found\n");
215 		return -ENOENT;
216 	}
217 
218 	/*
219 	 * stm32h7 can use either 'bus' or 'adc' clock for analog circuitry.
220 	 * So, choice is to have bus clock mandatory and adc clock optional.
221 	 * If optional 'adc' clock has been found, then try to use it first.
222 	 */
223 	if (priv->aclk) {
224 		/*
225 		 * Asynchronous clock modes (e.g. ckmode == 0)
226 		 * From spec: PLL output musn't exceed max rate
227 		 */
228 		rate = clk_get_rate(priv->aclk);
229 		if (!rate) {
230 			dev_err(&pdev->dev, "Invalid adc clock rate: 0\n");
231 			return -EINVAL;
232 		}
233 
234 		/* If duty is an error, kindly use at least /2 divider */
235 		duty = clk_get_scaled_duty_cycle(priv->aclk, 100);
236 		if (duty < 0)
237 			dev_warn(&pdev->dev, "adc clock duty: %d\n", duty);
238 
239 		for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
240 			ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
241 			presc = stm32h7_adc_ckmodes_spec[i].presc;
242 			div = stm32h7_adc_ckmodes_spec[i].div;
243 
244 			if (ckmode)
245 				continue;
246 
247 			/*
248 			 * For proper operation, clock duty cycle range is 49%
249 			 * to 51%. Apply at least /2 prescaler otherwise.
250 			 */
251 			if (div == 1 && (duty < 49 || duty > 51))
252 				continue;
253 
254 			if ((rate / div) <= priv->max_clk_rate)
255 				goto out;
256 		}
257 	}
258 
259 	/* Synchronous clock modes (e.g. ckmode is 1, 2 or 3) */
260 	rate = clk_get_rate(priv->bclk);
261 	if (!rate) {
262 		dev_err(&pdev->dev, "Invalid bus clock rate: 0\n");
263 		return -EINVAL;
264 	}
265 
266 	duty = clk_get_scaled_duty_cycle(priv->bclk, 100);
267 	if (duty < 0)
268 		dev_warn(&pdev->dev, "bus clock duty: %d\n", duty);
269 
270 	for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
271 		ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
272 		presc = stm32h7_adc_ckmodes_spec[i].presc;
273 		div = stm32h7_adc_ckmodes_spec[i].div;
274 
275 		if (!ckmode)
276 			continue;
277 
278 		if (div == 1 && (duty < 49 || duty > 51))
279 			continue;
280 
281 		if ((rate / div) <= priv->max_clk_rate)
282 			goto out;
283 	}
284 
285 	dev_err(&pdev->dev, "adc clk selection failed\n");
286 	return -EINVAL;
287 
288 out:
289 	/* rate used later by each ADC instance to control BOOST mode */
290 	priv->common.rate = rate / div;
291 
292 	/* Set common clock mode and prescaler */
293 	val = readl_relaxed(priv->common.base + STM32H7_ADC_CCR);
294 	val &= ~(STM32H7_CKMODE_MASK | STM32H7_PRESC_MASK);
295 	val |= ckmode << STM32H7_CKMODE_SHIFT;
296 	val |= presc << STM32H7_PRESC_SHIFT;
297 	writel_relaxed(val, priv->common.base + STM32H7_ADC_CCR);
298 
299 	dev_dbg(&pdev->dev, "Using %s clock/%d source at %ld kHz\n",
300 		ckmode ? "bus" : "adc", div, priv->common.rate / 1000);
301 
302 	return 0;
303 }
304 
305 /* STM32F4 common registers definitions */
306 static const struct stm32_adc_common_regs stm32f4_adc_common_regs = {
307 	.csr = STM32F4_ADC_CSR,
308 	.ccr = STM32F4_ADC_CCR,
309 	.eoc_msk = { STM32F4_EOC1, STM32F4_EOC2, STM32F4_EOC3},
310 	.ovr_msk = { STM32F4_OVR1, STM32F4_OVR2, STM32F4_OVR3},
311 	.ier = STM32F4_ADC_CR1,
312 	.eocie_msk = STM32F4_EOCIE,
313 };
314 
315 /* STM32H7 common registers definitions */
316 static const struct stm32_adc_common_regs stm32h7_adc_common_regs = {
317 	.csr = STM32H7_ADC_CSR,
318 	.ccr = STM32H7_ADC_CCR,
319 	.eoc_msk = { STM32H7_EOC_MST, STM32H7_EOC_SLV},
320 	.ovr_msk = { STM32H7_OVR_MST, STM32H7_OVR_SLV},
321 	.ier = STM32H7_ADC_IER,
322 	.eocie_msk = STM32H7_EOCIE,
323 };
324 
325 static const unsigned int stm32_adc_offset[STM32_ADC_MAX_ADCS] = {
326 	0, STM32_ADC_OFFSET, STM32_ADC_OFFSET * 2,
327 };
328 
329 static unsigned int stm32_adc_eoc_enabled(struct stm32_adc_priv *priv,
330 					  unsigned int adc)
331 {
332 	u32 ier, offset = stm32_adc_offset[adc];
333 
334 	ier = readl_relaxed(priv->common.base + offset + priv->cfg->regs->ier);
335 
336 	return ier & priv->cfg->regs->eocie_msk;
337 }
338 
339 /* ADC common interrupt for all instances */
340 static void stm32_adc_irq_handler(struct irq_desc *desc)
341 {
342 	struct stm32_adc_priv *priv = irq_desc_get_handler_data(desc);
343 	struct irq_chip *chip = irq_desc_get_chip(desc);
344 	int i;
345 	u32 status;
346 
347 	chained_irq_enter(chip, desc);
348 	status = readl_relaxed(priv->common.base + priv->cfg->regs->csr);
349 
350 	/*
351 	 * End of conversion may be handled by using IRQ or DMA. There may be a
352 	 * race here when two conversions complete at the same time on several
353 	 * ADCs. EOC may be read 'set' for several ADCs, with:
354 	 * - an ADC configured to use DMA (EOC triggers the DMA request, and
355 	 *   is then automatically cleared by DR read in hardware)
356 	 * - an ADC configured to use IRQs (EOCIE bit is set. The handler must
357 	 *   be called in this case)
358 	 * So both EOC status bit in CSR and EOCIE control bit must be checked
359 	 * before invoking the interrupt handler (e.g. call ISR only for
360 	 * IRQ-enabled ADCs).
361 	 */
362 	for (i = 0; i < priv->nb_adc_max; i++) {
363 		if ((status & priv->cfg->regs->eoc_msk[i] &&
364 		     stm32_adc_eoc_enabled(priv, i)) ||
365 		     (status & priv->cfg->regs->ovr_msk[i]))
366 			generic_handle_domain_irq(priv->domain, i);
367 	}
368 
369 	chained_irq_exit(chip, desc);
370 };
371 
372 static int stm32_adc_domain_map(struct irq_domain *d, unsigned int irq,
373 				irq_hw_number_t hwirq)
374 {
375 	irq_set_chip_data(irq, d->host_data);
376 	irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_level_irq);
377 
378 	return 0;
379 }
380 
381 static void stm32_adc_domain_unmap(struct irq_domain *d, unsigned int irq)
382 {
383 	irq_set_chip_and_handler(irq, NULL, NULL);
384 	irq_set_chip_data(irq, NULL);
385 }
386 
387 static const struct irq_domain_ops stm32_adc_domain_ops = {
388 	.map = stm32_adc_domain_map,
389 	.unmap  = stm32_adc_domain_unmap,
390 	.xlate = irq_domain_xlate_onecell,
391 };
392 
393 static int stm32_adc_irq_probe(struct platform_device *pdev,
394 			       struct stm32_adc_priv *priv)
395 {
396 	struct device_node *np = pdev->dev.of_node;
397 	unsigned int i;
398 
399 	/*
400 	 * Interrupt(s) must be provided, depending on the compatible:
401 	 * - stm32f4/h7 shares a common interrupt line.
402 	 * - stm32mp1, has one line per ADC
403 	 */
404 	for (i = 0; i < priv->cfg->num_irqs; i++) {
405 		priv->irq[i] = platform_get_irq(pdev, i);
406 		if (priv->irq[i] < 0)
407 			return priv->irq[i];
408 	}
409 
410 	priv->domain = irq_domain_add_simple(np, STM32_ADC_MAX_ADCS, 0,
411 					     &stm32_adc_domain_ops,
412 					     priv);
413 	if (!priv->domain) {
414 		dev_err(&pdev->dev, "Failed to add irq domain\n");
415 		return -ENOMEM;
416 	}
417 
418 	for (i = 0; i < priv->cfg->num_irqs; i++) {
419 		irq_set_chained_handler(priv->irq[i], stm32_adc_irq_handler);
420 		irq_set_handler_data(priv->irq[i], priv);
421 	}
422 
423 	return 0;
424 }
425 
426 static void stm32_adc_irq_remove(struct platform_device *pdev,
427 				 struct stm32_adc_priv *priv)
428 {
429 	int hwirq;
430 	unsigned int i;
431 
432 	for (hwirq = 0; hwirq < priv->nb_adc_max; hwirq++)
433 		irq_dispose_mapping(irq_find_mapping(priv->domain, hwirq));
434 	irq_domain_remove(priv->domain);
435 
436 	for (i = 0; i < priv->cfg->num_irqs; i++)
437 		irq_set_chained_handler(priv->irq[i], NULL);
438 }
439 
440 static int stm32_adc_core_switches_supply_en(struct stm32_adc_priv *priv,
441 					     struct device *dev)
442 {
443 	int ret;
444 
445 	/*
446 	 * On STM32H7 and STM32MP1, the ADC inputs are multiplexed with analog
447 	 * switches (via PCSEL) which have reduced performances when their
448 	 * supply is below 2.7V (vdda by default):
449 	 * - Voltage booster can be used, to get full ADC performances
450 	 *   (increases power consumption).
451 	 * - Vdd can be used to supply them, if above 2.7V (STM32MP1 only).
452 	 *
453 	 * Recommended settings for ANASWVDD and EN_BOOSTER:
454 	 * - vdda < 2.7V but vdd > 2.7V: ANASWVDD = 1, EN_BOOSTER = 0 (stm32mp1)
455 	 * - vdda < 2.7V and vdd < 2.7V: ANASWVDD = 0, EN_BOOSTER = 1
456 	 * - vdda >= 2.7V:               ANASWVDD = 0, EN_BOOSTER = 0 (default)
457 	 */
458 	if (priv->vdda_uv < 2700000) {
459 		if (priv->syscfg && priv->vdd_uv > 2700000) {
460 			ret = regulator_enable(priv->vdd);
461 			if (ret < 0) {
462 				dev_err(dev, "vdd enable failed %d\n", ret);
463 				return ret;
464 			}
465 
466 			ret = regmap_write(priv->syscfg,
467 					   STM32MP1_SYSCFG_PMCSETR,
468 					   STM32MP1_SYSCFG_ANASWVDD_MASK);
469 			if (ret < 0) {
470 				regulator_disable(priv->vdd);
471 				dev_err(dev, "vdd select failed, %d\n", ret);
472 				return ret;
473 			}
474 			dev_dbg(dev, "analog switches supplied by vdd\n");
475 
476 			return 0;
477 		}
478 
479 		if (priv->booster) {
480 			/*
481 			 * This is optional, as this is a trade-off between
482 			 * analog performance and power consumption.
483 			 */
484 			ret = regulator_enable(priv->booster);
485 			if (ret < 0) {
486 				dev_err(dev, "booster enable failed %d\n", ret);
487 				return ret;
488 			}
489 			dev_dbg(dev, "analog switches supplied by booster\n");
490 
491 			return 0;
492 		}
493 	}
494 
495 	/* Fallback using vdda (default), nothing to do */
496 	dev_dbg(dev, "analog switches supplied by vdda (%d uV)\n",
497 		priv->vdda_uv);
498 
499 	return 0;
500 }
501 
502 static void stm32_adc_core_switches_supply_dis(struct stm32_adc_priv *priv)
503 {
504 	if (priv->vdda_uv < 2700000) {
505 		if (priv->syscfg && priv->vdd_uv > 2700000) {
506 			regmap_write(priv->syscfg, STM32MP1_SYSCFG_PMCCLRR,
507 				     STM32MP1_SYSCFG_ANASWVDD_MASK);
508 			regulator_disable(priv->vdd);
509 			return;
510 		}
511 		if (priv->booster)
512 			regulator_disable(priv->booster);
513 	}
514 }
515 
516 static int stm32_adc_core_hw_start(struct device *dev)
517 {
518 	struct stm32_adc_common *common = dev_get_drvdata(dev);
519 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
520 	int ret;
521 
522 	ret = regulator_enable(priv->vdda);
523 	if (ret < 0) {
524 		dev_err(dev, "vdda enable failed %d\n", ret);
525 		return ret;
526 	}
527 
528 	ret = regulator_get_voltage(priv->vdda);
529 	if (ret < 0) {
530 		dev_err(dev, "vdda get voltage failed, %d\n", ret);
531 		goto err_vdda_disable;
532 	}
533 	priv->vdda_uv = ret;
534 
535 	ret = stm32_adc_core_switches_supply_en(priv, dev);
536 	if (ret < 0)
537 		goto err_vdda_disable;
538 
539 	ret = regulator_enable(priv->vref);
540 	if (ret < 0) {
541 		dev_err(dev, "vref enable failed\n");
542 		goto err_switches_dis;
543 	}
544 
545 	ret = clk_prepare_enable(priv->bclk);
546 	if (ret < 0) {
547 		dev_err(dev, "bus clk enable failed\n");
548 		goto err_regulator_disable;
549 	}
550 
551 	ret = clk_prepare_enable(priv->aclk);
552 	if (ret < 0) {
553 		dev_err(dev, "adc clk enable failed\n");
554 		goto err_bclk_disable;
555 	}
556 
557 	writel_relaxed(priv->ccr_bak, priv->common.base + priv->cfg->regs->ccr);
558 
559 	return 0;
560 
561 err_bclk_disable:
562 	clk_disable_unprepare(priv->bclk);
563 err_regulator_disable:
564 	regulator_disable(priv->vref);
565 err_switches_dis:
566 	stm32_adc_core_switches_supply_dis(priv);
567 err_vdda_disable:
568 	regulator_disable(priv->vdda);
569 
570 	return ret;
571 }
572 
573 static void stm32_adc_core_hw_stop(struct device *dev)
574 {
575 	struct stm32_adc_common *common = dev_get_drvdata(dev);
576 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
577 
578 	/* Backup CCR that may be lost (depends on power state to achieve) */
579 	priv->ccr_bak = readl_relaxed(priv->common.base + priv->cfg->regs->ccr);
580 	clk_disable_unprepare(priv->aclk);
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_identification(struct platform_device *pdev,
651 					  struct stm32_adc_priv *priv)
652 {
653 	struct device_node *np = pdev->dev.of_node;
654 	struct device_node *child;
655 	const char *compat;
656 	int ret, count = 0;
657 	u32 id, val;
658 
659 	if (!priv->cfg->ipid)
660 		return 0;
661 
662 	id = FIELD_GET(STM32MP1_IPIDR_MASK,
663 		       readl_relaxed(priv->common.base + STM32MP1_ADC_IPDR));
664 	if (id != priv->cfg->ipid) {
665 		dev_err(&pdev->dev, "Unexpected IP version: 0x%x", id);
666 		return -EINVAL;
667 	}
668 
669 	for_each_child_of_node(np, child) {
670 		ret = of_property_read_string(child, "compatible", &compat);
671 		if (ret)
672 			continue;
673 		/* Count child nodes with stm32 adc compatible */
674 		if (strstr(compat, "st,stm32") && strstr(compat, "adc"))
675 			count++;
676 	}
677 
678 	val = readl_relaxed(priv->common.base + STM32MP1_ADC_HWCFGR0);
679 	priv->nb_adc_max = FIELD_GET(STM32MP1_ADCNUM_MASK, val);
680 	if (count > priv->nb_adc_max) {
681 		dev_err(&pdev->dev, "Unexpected child number: %d", count);
682 		return -EINVAL;
683 	}
684 
685 	val = readl_relaxed(priv->common.base + STM32MP1_ADC_VERR);
686 	dev_dbg(&pdev->dev, "ADC version: %lu.%lu\n",
687 		FIELD_GET(STM32MP1_MAJREV_MASK, val),
688 		FIELD_GET(STM32MP1_MINREV_MASK, val));
689 
690 	return 0;
691 }
692 
693 static int stm32_adc_probe(struct platform_device *pdev)
694 {
695 	struct stm32_adc_priv *priv;
696 	struct device *dev = &pdev->dev;
697 	struct device_node *np = pdev->dev.of_node;
698 	struct resource *res;
699 	u32 max_rate;
700 	int ret;
701 
702 	if (!pdev->dev.of_node)
703 		return -ENODEV;
704 
705 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
706 	if (!priv)
707 		return -ENOMEM;
708 	platform_set_drvdata(pdev, &priv->common);
709 
710 	priv->cfg = (const struct stm32_adc_priv_cfg *)
711 		of_match_device(dev->driver->of_match_table, dev)->data;
712 	priv->nb_adc_max = priv->cfg->num_adcs;
713 	spin_lock_init(&priv->common.lock);
714 
715 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
716 	priv->common.base = devm_ioremap_resource(&pdev->dev, res);
717 	if (IS_ERR(priv->common.base))
718 		return PTR_ERR(priv->common.base);
719 	priv->common.phys_base = res->start;
720 
721 	priv->vdda = devm_regulator_get(&pdev->dev, "vdda");
722 	if (IS_ERR(priv->vdda))
723 		return dev_err_probe(&pdev->dev, PTR_ERR(priv->vdda),
724 				     "vdda get failed\n");
725 
726 	priv->vref = devm_regulator_get(&pdev->dev, "vref");
727 	if (IS_ERR(priv->vref))
728 		return dev_err_probe(&pdev->dev, PTR_ERR(priv->vref),
729 				     "vref get failed\n");
730 
731 	priv->aclk = devm_clk_get_optional(&pdev->dev, "adc");
732 	if (IS_ERR(priv->aclk))
733 		return dev_err_probe(&pdev->dev, PTR_ERR(priv->aclk),
734 				     "Can't get 'adc' clock\n");
735 
736 	priv->bclk = devm_clk_get_optional(&pdev->dev, "bus");
737 	if (IS_ERR(priv->bclk))
738 		return dev_err_probe(&pdev->dev, PTR_ERR(priv->bclk),
739 				     "Can't get 'bus' clock\n");
740 
741 	ret = stm32_adc_core_switches_probe(dev, priv);
742 	if (ret)
743 		return ret;
744 
745 	pm_runtime_get_noresume(dev);
746 	pm_runtime_set_active(dev);
747 	pm_runtime_set_autosuspend_delay(dev, STM32_ADC_CORE_SLEEP_DELAY_MS);
748 	pm_runtime_use_autosuspend(dev);
749 	pm_runtime_enable(dev);
750 
751 	ret = stm32_adc_core_hw_start(dev);
752 	if (ret)
753 		goto err_pm_stop;
754 
755 	ret = stm32_adc_probe_identification(pdev, priv);
756 	if (ret < 0)
757 		goto err_hw_stop;
758 
759 	ret = regulator_get_voltage(priv->vref);
760 	if (ret < 0) {
761 		dev_err(&pdev->dev, "vref get voltage failed, %d\n", ret);
762 		goto err_hw_stop;
763 	}
764 	priv->common.vref_mv = ret / 1000;
765 	dev_dbg(&pdev->dev, "vref+=%dmV\n", priv->common.vref_mv);
766 
767 	ret = of_property_read_u32(pdev->dev.of_node, "st,max-clk-rate-hz",
768 				   &max_rate);
769 	if (!ret)
770 		priv->max_clk_rate = min(max_rate, priv->cfg->max_clk_rate_hz);
771 	else
772 		priv->max_clk_rate = priv->cfg->max_clk_rate_hz;
773 
774 	ret = priv->cfg->clk_sel(pdev, priv);
775 	if (ret < 0)
776 		goto err_hw_stop;
777 
778 	ret = stm32_adc_irq_probe(pdev, priv);
779 	if (ret < 0)
780 		goto err_hw_stop;
781 
782 	ret = of_platform_populate(np, NULL, NULL, &pdev->dev);
783 	if (ret < 0) {
784 		dev_err(&pdev->dev, "failed to populate DT children\n");
785 		goto err_irq_remove;
786 	}
787 
788 	pm_runtime_mark_last_busy(dev);
789 	pm_runtime_put_autosuspend(dev);
790 
791 	return 0;
792 
793 err_irq_remove:
794 	stm32_adc_irq_remove(pdev, priv);
795 err_hw_stop:
796 	stm32_adc_core_hw_stop(dev);
797 err_pm_stop:
798 	pm_runtime_disable(dev);
799 	pm_runtime_set_suspended(dev);
800 	pm_runtime_put_noidle(dev);
801 
802 	return ret;
803 }
804 
805 static int stm32_adc_remove(struct platform_device *pdev)
806 {
807 	struct stm32_adc_common *common = platform_get_drvdata(pdev);
808 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
809 
810 	pm_runtime_get_sync(&pdev->dev);
811 	of_platform_depopulate(&pdev->dev);
812 	stm32_adc_irq_remove(pdev, priv);
813 	stm32_adc_core_hw_stop(&pdev->dev);
814 	pm_runtime_disable(&pdev->dev);
815 	pm_runtime_set_suspended(&pdev->dev);
816 	pm_runtime_put_noidle(&pdev->dev);
817 
818 	return 0;
819 }
820 
821 static int stm32_adc_core_runtime_suspend(struct device *dev)
822 {
823 	stm32_adc_core_hw_stop(dev);
824 
825 	return 0;
826 }
827 
828 static int stm32_adc_core_runtime_resume(struct device *dev)
829 {
830 	return stm32_adc_core_hw_start(dev);
831 }
832 
833 static int stm32_adc_core_runtime_idle(struct device *dev)
834 {
835 	pm_runtime_mark_last_busy(dev);
836 
837 	return 0;
838 }
839 
840 static DEFINE_RUNTIME_DEV_PM_OPS(stm32_adc_core_pm_ops,
841 				stm32_adc_core_runtime_suspend,
842 				stm32_adc_core_runtime_resume,
843 				stm32_adc_core_runtime_idle);
844 
845 static const struct stm32_adc_priv_cfg stm32f4_adc_priv_cfg = {
846 	.regs = &stm32f4_adc_common_regs,
847 	.clk_sel = stm32f4_adc_clk_sel,
848 	.max_clk_rate_hz = 36000000,
849 	.num_irqs = 1,
850 	.num_adcs = 3,
851 };
852 
853 static const struct stm32_adc_priv_cfg stm32h7_adc_priv_cfg = {
854 	.regs = &stm32h7_adc_common_regs,
855 	.clk_sel = stm32h7_adc_clk_sel,
856 	.max_clk_rate_hz = 36000000,
857 	.has_syscfg = HAS_VBOOSTER,
858 	.num_irqs = 1,
859 	.num_adcs = 2,
860 };
861 
862 static const struct stm32_adc_priv_cfg stm32mp1_adc_priv_cfg = {
863 	.regs = &stm32h7_adc_common_regs,
864 	.clk_sel = stm32h7_adc_clk_sel,
865 	.max_clk_rate_hz = 36000000,
866 	.has_syscfg = HAS_VBOOSTER | HAS_ANASWVDD,
867 	.ipid = STM32MP15_IPIDR_NUMBER,
868 	.num_irqs = 2,
869 };
870 
871 static const struct of_device_id stm32_adc_of_match[] = {
872 	{
873 		.compatible = "st,stm32f4-adc-core",
874 		.data = (void *)&stm32f4_adc_priv_cfg
875 	}, {
876 		.compatible = "st,stm32h7-adc-core",
877 		.data = (void *)&stm32h7_adc_priv_cfg
878 	}, {
879 		.compatible = "st,stm32mp1-adc-core",
880 		.data = (void *)&stm32mp1_adc_priv_cfg
881 	}, {
882 	},
883 };
884 MODULE_DEVICE_TABLE(of, stm32_adc_of_match);
885 
886 static struct platform_driver stm32_adc_driver = {
887 	.probe = stm32_adc_probe,
888 	.remove = stm32_adc_remove,
889 	.driver = {
890 		.name = "stm32-adc-core",
891 		.of_match_table = stm32_adc_of_match,
892 		.pm = pm_ptr(&stm32_adc_core_pm_ops),
893 	},
894 };
895 module_platform_driver(stm32_adc_driver);
896 
897 MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
898 MODULE_DESCRIPTION("STMicroelectronics STM32 ADC core driver");
899 MODULE_LICENSE("GPL v2");
900 MODULE_ALIAS("platform:stm32-adc-core");
901