xref: /linux/drivers/iio/adc/stm32-adc-core.c (revision 40d269c000bda9fcd276a0412a9cebd3f6e344c5)
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.h>
21 #include <linux/of_platform.h>
22 #include <linux/platform_device.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/property.h>
25 #include <linux/regmap.h>
26 #include <linux/regulator/consumer.h>
27 #include <linux/slab.h>
28 #include <linux/units.h>
29 
30 #include "stm32-adc-core.h"
31 
32 #define STM32_ADC_CORE_SLEEP_DELAY_MS	2000
33 
34 /* SYSCFG registers */
35 #define STM32MP1_SYSCFG_PMCSETR		0x04
36 #define STM32MP1_SYSCFG_PMCCLRR		0x44
37 
38 /* SYSCFG bit fields */
39 #define STM32MP1_SYSCFG_ANASWVDD_MASK	BIT(9)
40 
41 /* SYSCFG capability flags */
42 #define HAS_VBOOSTER		BIT(0)
43 #define HAS_ANASWVDD		BIT(1)
44 
45 /**
46  * struct stm32_adc_common_regs - stm32 common registers
47  * @csr:	common status register offset
48  * @ccr:	common control register offset
49  * @eoc_msk:    array of eoc (end of conversion flag) masks in csr for adc1..n
50  * @ovr_msk:    array of ovr (overrun flag) masks in csr for adc1..n
51  * @ier:	interrupt enable register offset for each adc
52  * @eocie_msk:	end of conversion interrupt enable mask in @ier
53  */
54 struct stm32_adc_common_regs {
55 	u32 csr;
56 	u32 ccr;
57 	u32 eoc_msk[STM32_ADC_MAX_ADCS];
58 	u32 ovr_msk[STM32_ADC_MAX_ADCS];
59 	u32 ier;
60 	u32 eocie_msk;
61 };
62 
63 struct stm32_adc_priv;
64 
65 /**
66  * struct stm32_adc_priv_cfg - stm32 core compatible configuration data
67  * @regs:	common registers for all instances
68  * @clk_sel:	clock selection routine
69  * @max_clk_rate_hz: maximum analog clock rate (Hz, from datasheet)
70  * @ipid:	adc identification number
71  * @has_syscfg: SYSCFG capability flags
72  * @num_irqs:	number of interrupt lines
73  * @num_adcs:   maximum number of ADC instances in the common registers
74  */
75 struct stm32_adc_priv_cfg {
76 	const struct stm32_adc_common_regs *regs;
77 	int (*clk_sel)(struct platform_device *, struct stm32_adc_priv *);
78 	u32 max_clk_rate_hz;
79 	u32 ipid;
80 	unsigned int has_syscfg;
81 	unsigned int num_irqs;
82 	unsigned int num_adcs;
83 };
84 
85 /**
86  * struct stm32_adc_priv - stm32 ADC core private data
87  * @irq:		irq(s) for ADC block
88  * @nb_adc_max:		actual maximum number of instance per ADC block
89  * @domain:		irq domain reference
90  * @aclk:		clock reference for the analog circuitry
91  * @bclk:		bus clock common for all ADCs, depends on part used
92  * @max_clk_rate:	desired maximum clock rate
93  * @booster:		booster supply reference
94  * @vdd:		vdd supply reference
95  * @vdda:		vdda analog supply reference
96  * @vref:		regulator reference
97  * @vdd_uv:		vdd supply voltage (microvolts)
98  * @vdda_uv:		vdda supply voltage (microvolts)
99  * @cfg:		compatible configuration data
100  * @common:		common data for all ADC instances
101  * @ccr_bak:		backup CCR in low power mode
102  * @syscfg:		reference to syscon, system control registers
103  */
104 struct stm32_adc_priv {
105 	int				irq[STM32_ADC_MAX_ADCS];
106 	unsigned int			nb_adc_max;
107 	struct irq_domain		*domain;
108 	struct clk			*aclk;
109 	struct clk			*bclk;
110 	u32				max_clk_rate;
111 	struct regulator		*booster;
112 	struct regulator		*vdd;
113 	struct regulator		*vdda;
114 	struct regulator		*vref;
115 	int				vdd_uv;
116 	int				vdda_uv;
117 	const struct stm32_adc_priv_cfg	*cfg;
118 	struct stm32_adc_common		common;
119 	u32				ccr_bak;
120 	struct regmap			*syscfg;
121 };
122 
123 static struct stm32_adc_priv *to_stm32_adc_priv(struct stm32_adc_common *com)
124 {
125 	return container_of(com, struct stm32_adc_priv, common);
126 }
127 
128 /* STM32F4 ADC internal common clock prescaler division ratios */
129 static int stm32f4_pclk_div[] = {2, 4, 6, 8};
130 
131 /**
132  * stm32f4_adc_clk_sel() - Select stm32f4 ADC common clock prescaler
133  * @pdev: platform device
134  * @priv: stm32 ADC core private data
135  * Select clock prescaler used for analog conversions, before using ADC.
136  */
137 static int stm32f4_adc_clk_sel(struct platform_device *pdev,
138 			       struct stm32_adc_priv *priv)
139 {
140 	unsigned long rate;
141 	u32 val;
142 	int i;
143 
144 	/* stm32f4 has one clk input for analog (mandatory), enforce it here */
145 	if (!priv->aclk) {
146 		dev_err(&pdev->dev, "No 'adc' clock found\n");
147 		return -ENOENT;
148 	}
149 
150 	rate = clk_get_rate(priv->aclk);
151 	if (!rate) {
152 		dev_err(&pdev->dev, "Invalid clock rate: 0\n");
153 		return -EINVAL;
154 	}
155 
156 	for (i = 0; i < ARRAY_SIZE(stm32f4_pclk_div); i++) {
157 		if ((rate / stm32f4_pclk_div[i]) <= priv->max_clk_rate)
158 			break;
159 	}
160 	if (i >= ARRAY_SIZE(stm32f4_pclk_div)) {
161 		dev_err(&pdev->dev, "adc clk selection failed\n");
162 		return -EINVAL;
163 	}
164 
165 	priv->common.rate = rate / stm32f4_pclk_div[i];
166 	val = readl_relaxed(priv->common.base + STM32F4_ADC_CCR);
167 	val &= ~STM32F4_ADC_ADCPRE_MASK;
168 	val |= i << STM32F4_ADC_ADCPRE_SHIFT;
169 	writel_relaxed(val, priv->common.base + STM32F4_ADC_CCR);
170 
171 	dev_dbg(&pdev->dev, "Using analog clock source at %ld kHz\n",
172 		priv->common.rate / 1000);
173 
174 	return 0;
175 }
176 
177 /**
178  * struct stm32h7_adc_ck_spec - specification for stm32h7 adc clock
179  * @ckmode: ADC clock mode, Async or sync with prescaler.
180  * @presc: prescaler bitfield for async clock mode
181  * @div: prescaler division ratio
182  */
183 struct stm32h7_adc_ck_spec {
184 	u32 ckmode;
185 	u32 presc;
186 	int div;
187 };
188 
189 static const struct stm32h7_adc_ck_spec stm32h7_adc_ckmodes_spec[] = {
190 	/* 00: CK_ADC[1..3]: Asynchronous clock modes */
191 	{ 0, 0, 1 },
192 	{ 0, 1, 2 },
193 	{ 0, 2, 4 },
194 	{ 0, 3, 6 },
195 	{ 0, 4, 8 },
196 	{ 0, 5, 10 },
197 	{ 0, 6, 12 },
198 	{ 0, 7, 16 },
199 	{ 0, 8, 32 },
200 	{ 0, 9, 64 },
201 	{ 0, 10, 128 },
202 	{ 0, 11, 256 },
203 	/* HCLK used: Synchronous clock modes (1, 2 or 4 prescaler) */
204 	{ 1, 0, 1 },
205 	{ 2, 0, 2 },
206 	{ 3, 0, 4 },
207 };
208 
209 static int stm32h7_adc_clk_sel(struct platform_device *pdev,
210 			       struct stm32_adc_priv *priv)
211 {
212 	u32 ckmode, presc, val;
213 	unsigned long rate;
214 	int i, div, duty;
215 
216 	/* stm32h7 bus clock is common for all ADC instances (mandatory) */
217 	if (!priv->bclk) {
218 		dev_err(&pdev->dev, "No 'bus' clock found\n");
219 		return -ENOENT;
220 	}
221 
222 	/*
223 	 * stm32h7 can use either 'bus' or 'adc' clock for analog circuitry.
224 	 * So, choice is to have bus clock mandatory and adc clock optional.
225 	 * If optional 'adc' clock has been found, then try to use it first.
226 	 */
227 	if (priv->aclk) {
228 		/*
229 		 * Asynchronous clock modes (e.g. ckmode == 0)
230 		 * From spec: PLL output musn't exceed max rate
231 		 */
232 		rate = clk_get_rate(priv->aclk);
233 		if (!rate) {
234 			dev_err(&pdev->dev, "Invalid adc clock rate: 0\n");
235 			return -EINVAL;
236 		}
237 
238 		/* If duty is an error, kindly use at least /2 divider */
239 		duty = clk_get_scaled_duty_cycle(priv->aclk, 100);
240 		if (duty < 0)
241 			dev_warn(&pdev->dev, "adc clock duty: %d\n", duty);
242 
243 		for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
244 			ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
245 			presc = stm32h7_adc_ckmodes_spec[i].presc;
246 			div = stm32h7_adc_ckmodes_spec[i].div;
247 
248 			if (ckmode)
249 				continue;
250 
251 			/*
252 			 * For proper operation, clock duty cycle range is 49%
253 			 * to 51%. Apply at least /2 prescaler otherwise.
254 			 */
255 			if (div == 1 && (duty < 49 || duty > 51))
256 				continue;
257 
258 			if ((rate / div) <= priv->max_clk_rate)
259 				goto out;
260 		}
261 	}
262 
263 	/* Synchronous clock modes (e.g. ckmode is 1, 2 or 3) */
264 	rate = clk_get_rate(priv->bclk);
265 	if (!rate) {
266 		dev_err(&pdev->dev, "Invalid bus clock rate: 0\n");
267 		return -EINVAL;
268 	}
269 
270 	duty = clk_get_scaled_duty_cycle(priv->bclk, 100);
271 	if (duty < 0)
272 		dev_warn(&pdev->dev, "bus clock duty: %d\n", duty);
273 
274 	for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
275 		ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
276 		presc = stm32h7_adc_ckmodes_spec[i].presc;
277 		div = stm32h7_adc_ckmodes_spec[i].div;
278 
279 		if (!ckmode)
280 			continue;
281 
282 		if (div == 1 && (duty < 49 || duty > 51))
283 			continue;
284 
285 		if ((rate / div) <= priv->max_clk_rate)
286 			goto out;
287 	}
288 
289 	dev_err(&pdev->dev, "adc clk selection failed\n");
290 	return -EINVAL;
291 
292 out:
293 	/* rate used later by each ADC instance to control BOOST mode */
294 	priv->common.rate = rate / div;
295 
296 	/* Set common clock mode and prescaler */
297 	val = readl_relaxed(priv->common.base + STM32H7_ADC_CCR);
298 	val &= ~(STM32H7_CKMODE_MASK | STM32H7_PRESC_MASK);
299 	val |= ckmode << STM32H7_CKMODE_SHIFT;
300 	val |= presc << STM32H7_PRESC_SHIFT;
301 	writel_relaxed(val, priv->common.base + STM32H7_ADC_CCR);
302 
303 	dev_dbg(&pdev->dev, "Using %s clock/%d source at %ld kHz\n",
304 		ckmode ? "bus" : "adc", div, priv->common.rate / 1000);
305 
306 	return 0;
307 }
308 
309 /* STM32F4 common registers definitions */
310 static const struct stm32_adc_common_regs stm32f4_adc_common_regs = {
311 	.csr = STM32F4_ADC_CSR,
312 	.ccr = STM32F4_ADC_CCR,
313 	.eoc_msk = { STM32F4_EOC1, STM32F4_EOC2, STM32F4_EOC3 },
314 	.ovr_msk = { STM32F4_OVR1, STM32F4_OVR2, STM32F4_OVR3 },
315 	.ier = STM32F4_ADC_CR1,
316 	.eocie_msk = STM32F4_EOCIE,
317 };
318 
319 /* STM32H7 common registers definitions */
320 static const struct stm32_adc_common_regs stm32h7_adc_common_regs = {
321 	.csr = STM32H7_ADC_CSR,
322 	.ccr = STM32H7_ADC_CCR,
323 	.eoc_msk = { STM32H7_EOC_MST, STM32H7_EOC_SLV },
324 	.ovr_msk = { STM32H7_OVR_MST, STM32H7_OVR_SLV },
325 	.ier = STM32H7_ADC_IER,
326 	.eocie_msk = STM32H7_EOCIE,
327 };
328 
329 /* STM32MP13 common registers definitions */
330 static const struct stm32_adc_common_regs stm32mp13_adc_common_regs = {
331 	.csr = STM32H7_ADC_CSR,
332 	.ccr = STM32H7_ADC_CCR,
333 	.eoc_msk = { STM32H7_EOC_MST },
334 	.ovr_msk = { STM32H7_OVR_MST },
335 	.ier = STM32H7_ADC_IER,
336 	.eocie_msk = STM32H7_EOCIE,
337 };
338 
339 static const unsigned int stm32_adc_offset[STM32_ADC_MAX_ADCS] = {
340 	0, STM32_ADC_OFFSET, STM32_ADC_OFFSET * 2,
341 };
342 
343 static unsigned int stm32_adc_eoc_enabled(struct stm32_adc_priv *priv,
344 					  unsigned int adc)
345 {
346 	u32 ier, offset = stm32_adc_offset[adc];
347 
348 	ier = readl_relaxed(priv->common.base + offset + priv->cfg->regs->ier);
349 
350 	return ier & priv->cfg->regs->eocie_msk;
351 }
352 
353 /* ADC common interrupt for all instances */
354 static void stm32_adc_irq_handler(struct irq_desc *desc)
355 {
356 	struct stm32_adc_priv *priv = irq_desc_get_handler_data(desc);
357 	struct irq_chip *chip = irq_desc_get_chip(desc);
358 	int i;
359 	u32 status;
360 
361 	chained_irq_enter(chip, desc);
362 	status = readl_relaxed(priv->common.base + priv->cfg->regs->csr);
363 
364 	/*
365 	 * End of conversion may be handled by using IRQ or DMA. There may be a
366 	 * race here when two conversions complete at the same time on several
367 	 * ADCs. EOC may be read 'set' for several ADCs, with:
368 	 * - an ADC configured to use DMA (EOC triggers the DMA request, and
369 	 *   is then automatically cleared by DR read in hardware)
370 	 * - an ADC configured to use IRQs (EOCIE bit is set. The handler must
371 	 *   be called in this case)
372 	 * So both EOC status bit in CSR and EOCIE control bit must be checked
373 	 * before invoking the interrupt handler (e.g. call ISR only for
374 	 * IRQ-enabled ADCs).
375 	 */
376 	for (i = 0; i < priv->nb_adc_max; i++) {
377 		if ((status & priv->cfg->regs->eoc_msk[i] &&
378 		     stm32_adc_eoc_enabled(priv, i)) ||
379 		     (status & priv->cfg->regs->ovr_msk[i]))
380 			generic_handle_domain_irq(priv->domain, i);
381 	}
382 
383 	chained_irq_exit(chip, desc);
384 };
385 
386 static int stm32_adc_domain_map(struct irq_domain *d, unsigned int irq,
387 				irq_hw_number_t hwirq)
388 {
389 	irq_set_chip_data(irq, d->host_data);
390 	irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_level_irq);
391 
392 	return 0;
393 }
394 
395 static void stm32_adc_domain_unmap(struct irq_domain *d, unsigned int irq)
396 {
397 	irq_set_chip_and_handler(irq, NULL, NULL);
398 	irq_set_chip_data(irq, NULL);
399 }
400 
401 static const struct irq_domain_ops stm32_adc_domain_ops = {
402 	.map = stm32_adc_domain_map,
403 	.unmap  = stm32_adc_domain_unmap,
404 	.xlate = irq_domain_xlate_onecell,
405 };
406 
407 static int stm32_adc_irq_probe(struct platform_device *pdev,
408 			       struct stm32_adc_priv *priv)
409 {
410 	struct device_node *np = pdev->dev.of_node;
411 	unsigned int i;
412 
413 	/*
414 	 * Interrupt(s) must be provided, depending on the compatible:
415 	 * - stm32f4/h7 shares a common interrupt line.
416 	 * - stm32mp1, has one line per ADC
417 	 */
418 	for (i = 0; i < priv->cfg->num_irqs; i++) {
419 		priv->irq[i] = platform_get_irq(pdev, i);
420 		if (priv->irq[i] < 0)
421 			return priv->irq[i];
422 	}
423 
424 	priv->domain = irq_domain_add_simple(np, STM32_ADC_MAX_ADCS, 0,
425 					     &stm32_adc_domain_ops,
426 					     priv);
427 	if (!priv->domain) {
428 		dev_err(&pdev->dev, "Failed to add irq domain\n");
429 		return -ENOMEM;
430 	}
431 
432 	for (i = 0; i < priv->cfg->num_irqs; i++) {
433 		irq_set_chained_handler(priv->irq[i], stm32_adc_irq_handler);
434 		irq_set_handler_data(priv->irq[i], priv);
435 	}
436 
437 	return 0;
438 }
439 
440 static void stm32_adc_irq_remove(struct platform_device *pdev,
441 				 struct stm32_adc_priv *priv)
442 {
443 	int hwirq;
444 	unsigned int i;
445 
446 	for (hwirq = 0; hwirq < priv->nb_adc_max; hwirq++)
447 		irq_dispose_mapping(irq_find_mapping(priv->domain, hwirq));
448 	irq_domain_remove(priv->domain);
449 
450 	for (i = 0; i < priv->cfg->num_irqs; i++)
451 		irq_set_chained_handler(priv->irq[i], NULL);
452 }
453 
454 static int stm32_adc_core_switches_supply_en(struct stm32_adc_priv *priv,
455 					     struct device *dev)
456 {
457 	int ret;
458 
459 	/*
460 	 * On STM32H7 and STM32MP1, the ADC inputs are multiplexed with analog
461 	 * switches (via PCSEL) which have reduced performances when their
462 	 * supply is below 2.7V (vdda by default):
463 	 * - Voltage booster can be used, to get full ADC performances
464 	 *   (increases power consumption).
465 	 * - Vdd can be used to supply them, if above 2.7V (STM32MP1 only).
466 	 *
467 	 * Recommended settings for ANASWVDD and EN_BOOSTER:
468 	 * - vdda < 2.7V but vdd > 2.7V: ANASWVDD = 1, EN_BOOSTER = 0 (stm32mp1)
469 	 * - vdda < 2.7V and vdd < 2.7V: ANASWVDD = 0, EN_BOOSTER = 1
470 	 * - vdda >= 2.7V:               ANASWVDD = 0, EN_BOOSTER = 0 (default)
471 	 */
472 	if (priv->vdda_uv < 2700000) {
473 		if (priv->syscfg && priv->vdd_uv > 2700000) {
474 			ret = regulator_enable(priv->vdd);
475 			if (ret < 0) {
476 				dev_err(dev, "vdd enable failed %d\n", ret);
477 				return ret;
478 			}
479 
480 			ret = regmap_write(priv->syscfg,
481 					   STM32MP1_SYSCFG_PMCSETR,
482 					   STM32MP1_SYSCFG_ANASWVDD_MASK);
483 			if (ret < 0) {
484 				regulator_disable(priv->vdd);
485 				dev_err(dev, "vdd select failed, %d\n", ret);
486 				return ret;
487 			}
488 			dev_dbg(dev, "analog switches supplied by vdd\n");
489 
490 			return 0;
491 		}
492 
493 		if (priv->booster) {
494 			/*
495 			 * This is optional, as this is a trade-off between
496 			 * analog performance and power consumption.
497 			 */
498 			ret = regulator_enable(priv->booster);
499 			if (ret < 0) {
500 				dev_err(dev, "booster enable failed %d\n", ret);
501 				return ret;
502 			}
503 			dev_dbg(dev, "analog switches supplied by booster\n");
504 
505 			return 0;
506 		}
507 	}
508 
509 	/* Fallback using vdda (default), nothing to do */
510 	dev_dbg(dev, "analog switches supplied by vdda (%d uV)\n",
511 		priv->vdda_uv);
512 
513 	return 0;
514 }
515 
516 static void stm32_adc_core_switches_supply_dis(struct stm32_adc_priv *priv)
517 {
518 	if (priv->vdda_uv < 2700000) {
519 		if (priv->syscfg && priv->vdd_uv > 2700000) {
520 			regmap_write(priv->syscfg, STM32MP1_SYSCFG_PMCCLRR,
521 				     STM32MP1_SYSCFG_ANASWVDD_MASK);
522 			regulator_disable(priv->vdd);
523 			return;
524 		}
525 		if (priv->booster)
526 			regulator_disable(priv->booster);
527 	}
528 }
529 
530 static int stm32_adc_core_hw_start(struct device *dev)
531 {
532 	struct stm32_adc_common *common = dev_get_drvdata(dev);
533 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
534 	int ret;
535 
536 	ret = regulator_enable(priv->vdda);
537 	if (ret < 0) {
538 		dev_err(dev, "vdda enable failed %d\n", ret);
539 		return ret;
540 	}
541 
542 	ret = regulator_get_voltage(priv->vdda);
543 	if (ret < 0) {
544 		dev_err(dev, "vdda get voltage failed, %d\n", ret);
545 		goto err_vdda_disable;
546 	}
547 	priv->vdda_uv = ret;
548 
549 	ret = stm32_adc_core_switches_supply_en(priv, dev);
550 	if (ret < 0)
551 		goto err_vdda_disable;
552 
553 	ret = regulator_enable(priv->vref);
554 	if (ret < 0) {
555 		dev_err(dev, "vref enable failed\n");
556 		goto err_switches_dis;
557 	}
558 
559 	ret = clk_prepare_enable(priv->bclk);
560 	if (ret < 0) {
561 		dev_err(dev, "bus clk enable failed\n");
562 		goto err_regulator_disable;
563 	}
564 
565 	ret = clk_prepare_enable(priv->aclk);
566 	if (ret < 0) {
567 		dev_err(dev, "adc clk enable failed\n");
568 		goto err_bclk_disable;
569 	}
570 
571 	writel_relaxed(priv->ccr_bak, priv->common.base + priv->cfg->regs->ccr);
572 
573 	return 0;
574 
575 err_bclk_disable:
576 	clk_disable_unprepare(priv->bclk);
577 err_regulator_disable:
578 	regulator_disable(priv->vref);
579 err_switches_dis:
580 	stm32_adc_core_switches_supply_dis(priv);
581 err_vdda_disable:
582 	regulator_disable(priv->vdda);
583 
584 	return ret;
585 }
586 
587 static void stm32_adc_core_hw_stop(struct device *dev)
588 {
589 	struct stm32_adc_common *common = dev_get_drvdata(dev);
590 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
591 
592 	/* Backup CCR that may be lost (depends on power state to achieve) */
593 	priv->ccr_bak = readl_relaxed(priv->common.base + priv->cfg->regs->ccr);
594 	clk_disable_unprepare(priv->aclk);
595 	clk_disable_unprepare(priv->bclk);
596 	regulator_disable(priv->vref);
597 	stm32_adc_core_switches_supply_dis(priv);
598 	regulator_disable(priv->vdda);
599 }
600 
601 static int stm32_adc_core_switches_probe(struct device *dev,
602 					 struct stm32_adc_priv *priv)
603 {
604 	struct device_node *np = dev->of_node;
605 	int ret;
606 
607 	/* Analog switches supply can be controlled by syscfg (optional) */
608 	priv->syscfg = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
609 	if (IS_ERR(priv->syscfg)) {
610 		ret = PTR_ERR(priv->syscfg);
611 		if (ret != -ENODEV)
612 			return dev_err_probe(dev, ret, "Can't probe syscfg\n");
613 
614 		priv->syscfg = NULL;
615 	}
616 
617 	/* Booster can be used to supply analog switches (optional) */
618 	if (priv->cfg->has_syscfg & HAS_VBOOSTER &&
619 	    of_property_read_bool(np, "booster-supply")) {
620 		priv->booster = devm_regulator_get_optional(dev, "booster");
621 		if (IS_ERR(priv->booster)) {
622 			ret = PTR_ERR(priv->booster);
623 			if (ret != -ENODEV)
624 				return dev_err_probe(dev, ret, "can't get booster\n");
625 
626 			priv->booster = NULL;
627 		}
628 	}
629 
630 	/* Vdd can be used to supply analog switches (optional) */
631 	if (priv->cfg->has_syscfg & HAS_ANASWVDD &&
632 	    of_property_read_bool(np, "vdd-supply")) {
633 		priv->vdd = devm_regulator_get_optional(dev, "vdd");
634 		if (IS_ERR(priv->vdd)) {
635 			ret = PTR_ERR(priv->vdd);
636 			if (ret != -ENODEV)
637 				return dev_err_probe(dev, ret, "can't get vdd\n");
638 
639 			priv->vdd = NULL;
640 		}
641 	}
642 
643 	if (priv->vdd) {
644 		ret = regulator_enable(priv->vdd);
645 		if (ret < 0) {
646 			dev_err(dev, "vdd enable failed %d\n", ret);
647 			return ret;
648 		}
649 
650 		ret = regulator_get_voltage(priv->vdd);
651 		if (ret < 0) {
652 			dev_err(dev, "vdd get voltage failed %d\n", ret);
653 			regulator_disable(priv->vdd);
654 			return ret;
655 		}
656 		priv->vdd_uv = ret;
657 
658 		regulator_disable(priv->vdd);
659 	}
660 
661 	return 0;
662 }
663 
664 static int stm32_adc_probe_identification(struct platform_device *pdev,
665 					  struct stm32_adc_priv *priv)
666 {
667 	struct device_node *np = pdev->dev.of_node;
668 	struct device_node *child;
669 	const char *compat;
670 	int ret, count = 0;
671 	u32 id, val;
672 
673 	if (!priv->cfg->ipid)
674 		return 0;
675 
676 	id = FIELD_GET(STM32MP1_IPIDR_MASK,
677 		       readl_relaxed(priv->common.base + STM32MP1_ADC_IPDR));
678 	if (id != priv->cfg->ipid) {
679 		dev_err(&pdev->dev, "Unexpected IP version: 0x%x", id);
680 		return -EINVAL;
681 	}
682 
683 	for_each_child_of_node(np, child) {
684 		ret = of_property_read_string(child, "compatible", &compat);
685 		if (ret)
686 			continue;
687 		/* Count child nodes with stm32 adc compatible */
688 		if (strstr(compat, "st,stm32") && strstr(compat, "adc"))
689 			count++;
690 	}
691 
692 	val = readl_relaxed(priv->common.base + STM32MP1_ADC_HWCFGR0);
693 	priv->nb_adc_max = FIELD_GET(STM32MP1_ADCNUM_MASK, val);
694 	if (count > priv->nb_adc_max) {
695 		dev_err(&pdev->dev, "Unexpected child number: %d", count);
696 		return -EINVAL;
697 	}
698 
699 	val = readl_relaxed(priv->common.base + STM32MP1_ADC_VERR);
700 	dev_dbg(&pdev->dev, "ADC version: %lu.%lu\n",
701 		FIELD_GET(STM32MP1_MAJREV_MASK, val),
702 		FIELD_GET(STM32MP1_MINREV_MASK, val));
703 
704 	return 0;
705 }
706 
707 static int stm32_adc_probe(struct platform_device *pdev)
708 {
709 	struct stm32_adc_priv *priv;
710 	struct device *dev = &pdev->dev;
711 	struct device_node *np = pdev->dev.of_node;
712 	struct resource *res;
713 	u32 max_rate;
714 	int ret;
715 
716 	if (!pdev->dev.of_node)
717 		return -ENODEV;
718 
719 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
720 	if (!priv)
721 		return -ENOMEM;
722 	platform_set_drvdata(pdev, &priv->common);
723 
724 	priv->cfg = device_get_match_data(dev);
725 	priv->nb_adc_max = priv->cfg->num_adcs;
726 	spin_lock_init(&priv->common.lock);
727 
728 	priv->common.base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
729 	if (IS_ERR(priv->common.base))
730 		return PTR_ERR(priv->common.base);
731 	priv->common.phys_base = res->start;
732 
733 	priv->vdda = devm_regulator_get(&pdev->dev, "vdda");
734 	if (IS_ERR(priv->vdda))
735 		return dev_err_probe(&pdev->dev, PTR_ERR(priv->vdda),
736 				     "vdda get failed\n");
737 
738 	priv->vref = devm_regulator_get(&pdev->dev, "vref");
739 	if (IS_ERR(priv->vref))
740 		return dev_err_probe(&pdev->dev, PTR_ERR(priv->vref),
741 				     "vref get failed\n");
742 
743 	priv->aclk = devm_clk_get_optional(&pdev->dev, "adc");
744 	if (IS_ERR(priv->aclk))
745 		return dev_err_probe(&pdev->dev, PTR_ERR(priv->aclk),
746 				     "Can't get 'adc' clock\n");
747 
748 	priv->bclk = devm_clk_get_optional(&pdev->dev, "bus");
749 	if (IS_ERR(priv->bclk))
750 		return dev_err_probe(&pdev->dev, PTR_ERR(priv->bclk),
751 				     "Can't get 'bus' clock\n");
752 
753 	ret = stm32_adc_core_switches_probe(dev, priv);
754 	if (ret)
755 		return ret;
756 
757 	pm_runtime_get_noresume(dev);
758 	pm_runtime_set_active(dev);
759 	pm_runtime_set_autosuspend_delay(dev, STM32_ADC_CORE_SLEEP_DELAY_MS);
760 	pm_runtime_use_autosuspend(dev);
761 	pm_runtime_enable(dev);
762 
763 	ret = stm32_adc_core_hw_start(dev);
764 	if (ret)
765 		goto err_pm_stop;
766 
767 	ret = stm32_adc_probe_identification(pdev, priv);
768 	if (ret < 0)
769 		goto err_hw_stop;
770 
771 	ret = regulator_get_voltage(priv->vref);
772 	if (ret < 0) {
773 		dev_err(&pdev->dev, "vref get voltage failed, %d\n", ret);
774 		goto err_hw_stop;
775 	}
776 	priv->common.vref_mv = ret / 1000;
777 	dev_dbg(&pdev->dev, "vref+=%dmV\n", priv->common.vref_mv);
778 
779 	ret = of_property_read_u32(pdev->dev.of_node, "st,max-clk-rate-hz",
780 				   &max_rate);
781 	if (!ret)
782 		priv->max_clk_rate = min(max_rate, priv->cfg->max_clk_rate_hz);
783 	else
784 		priv->max_clk_rate = priv->cfg->max_clk_rate_hz;
785 
786 	ret = priv->cfg->clk_sel(pdev, priv);
787 	if (ret < 0)
788 		goto err_hw_stop;
789 
790 	ret = stm32_adc_irq_probe(pdev, priv);
791 	if (ret < 0)
792 		goto err_hw_stop;
793 
794 	ret = of_platform_populate(np, NULL, NULL, &pdev->dev);
795 	if (ret < 0) {
796 		dev_err(&pdev->dev, "failed to populate DT children\n");
797 		goto err_irq_remove;
798 	}
799 
800 	pm_runtime_mark_last_busy(dev);
801 	pm_runtime_put_autosuspend(dev);
802 
803 	return 0;
804 
805 err_irq_remove:
806 	stm32_adc_irq_remove(pdev, priv);
807 err_hw_stop:
808 	stm32_adc_core_hw_stop(dev);
809 err_pm_stop:
810 	pm_runtime_disable(dev);
811 	pm_runtime_set_suspended(dev);
812 	pm_runtime_put_noidle(dev);
813 
814 	return ret;
815 }
816 
817 static void stm32_adc_remove(struct platform_device *pdev)
818 {
819 	struct stm32_adc_common *common = platform_get_drvdata(pdev);
820 	struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
821 
822 	pm_runtime_get_sync(&pdev->dev);
823 	of_platform_depopulate(&pdev->dev);
824 	stm32_adc_irq_remove(pdev, priv);
825 	stm32_adc_core_hw_stop(&pdev->dev);
826 	pm_runtime_disable(&pdev->dev);
827 	pm_runtime_set_suspended(&pdev->dev);
828 	pm_runtime_put_noidle(&pdev->dev);
829 }
830 
831 static int stm32_adc_core_runtime_suspend(struct device *dev)
832 {
833 	stm32_adc_core_hw_stop(dev);
834 
835 	return 0;
836 }
837 
838 static int stm32_adc_core_runtime_resume(struct device *dev)
839 {
840 	return stm32_adc_core_hw_start(dev);
841 }
842 
843 static int stm32_adc_core_runtime_idle(struct device *dev)
844 {
845 	pm_runtime_mark_last_busy(dev);
846 
847 	return 0;
848 }
849 
850 static DEFINE_RUNTIME_DEV_PM_OPS(stm32_adc_core_pm_ops,
851 				stm32_adc_core_runtime_suspend,
852 				stm32_adc_core_runtime_resume,
853 				stm32_adc_core_runtime_idle);
854 
855 static const struct stm32_adc_priv_cfg stm32f4_adc_priv_cfg = {
856 	.regs = &stm32f4_adc_common_regs,
857 	.clk_sel = stm32f4_adc_clk_sel,
858 	.max_clk_rate_hz = 36000000,
859 	.num_irqs = 1,
860 	.num_adcs = 3,
861 };
862 
863 static const struct stm32_adc_priv_cfg stm32h7_adc_priv_cfg = {
864 	.regs = &stm32h7_adc_common_regs,
865 	.clk_sel = stm32h7_adc_clk_sel,
866 	.max_clk_rate_hz = 36000000,
867 	.has_syscfg = HAS_VBOOSTER,
868 	.num_irqs = 1,
869 	.num_adcs = 2,
870 };
871 
872 static const struct stm32_adc_priv_cfg stm32mp1_adc_priv_cfg = {
873 	.regs = &stm32h7_adc_common_regs,
874 	.clk_sel = stm32h7_adc_clk_sel,
875 	.max_clk_rate_hz = 36000000,
876 	.has_syscfg = HAS_VBOOSTER | HAS_ANASWVDD,
877 	.ipid = STM32MP15_IPIDR_NUMBER,
878 	.num_irqs = 2,
879 };
880 
881 static const struct stm32_adc_priv_cfg stm32mp13_adc_priv_cfg = {
882 	.regs = &stm32mp13_adc_common_regs,
883 	.clk_sel = stm32h7_adc_clk_sel,
884 	.max_clk_rate_hz = 75 * HZ_PER_MHZ,
885 	.ipid = STM32MP13_IPIDR_NUMBER,
886 	.num_irqs = 1,
887 };
888 
889 static const struct of_device_id stm32_adc_of_match[] = {
890 	{
891 		.compatible = "st,stm32f4-adc-core",
892 		.data = (void *)&stm32f4_adc_priv_cfg
893 	}, {
894 		.compatible = "st,stm32h7-adc-core",
895 		.data = (void *)&stm32h7_adc_priv_cfg
896 	}, {
897 		.compatible = "st,stm32mp1-adc-core",
898 		.data = (void *)&stm32mp1_adc_priv_cfg
899 	}, {
900 		.compatible = "st,stm32mp13-adc-core",
901 		.data = (void *)&stm32mp13_adc_priv_cfg
902 	}, {
903 	},
904 };
905 MODULE_DEVICE_TABLE(of, stm32_adc_of_match);
906 
907 static struct platform_driver stm32_adc_driver = {
908 	.probe = stm32_adc_probe,
909 	.remove_new = stm32_adc_remove,
910 	.driver = {
911 		.name = "stm32-adc-core",
912 		.of_match_table = stm32_adc_of_match,
913 		.pm = pm_ptr(&stm32_adc_core_pm_ops),
914 	},
915 };
916 module_platform_driver(stm32_adc_driver);
917 
918 MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
919 MODULE_DESCRIPTION("STMicroelectronics STM32 ADC core driver");
920 MODULE_LICENSE("GPL v2");
921 MODULE_ALIAS("platform:stm32-adc-core");
922