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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * This file is part of STM32 ADC driver
4 *
5 * Copyright (C) 2016, STMicroelectronics - All Rights Reserved
6 * Author: Fabrice Gasnier <fabrice.gasnier@st.com>.
7 *
8 * Inspired from: fsl-imx25-tsadc
9 *
10 */
11
12#include <linux/clk.h>
13#include <linux/interrupt.h>
14#include <linux/irqchip/chained_irq.h>
15#include <linux/irqdesc.h>
16#include <linux/irqdomain.h>
17#include <linux/mfd/syscon.h>
18#include <linux/module.h>
19#include <linux/of_device.h>
20#include <linux/pm_runtime.h>
21#include <linux/regmap.h>
22#include <linux/regulator/consumer.h>
23#include <linux/slab.h>
24
25#include "stm32-adc-core.h"
26
27#define STM32_ADC_CORE_SLEEP_DELAY_MS 2000
28
29/* SYSCFG registers */
30#define STM32MP1_SYSCFG_PMCSETR 0x04
31#define STM32MP1_SYSCFG_PMCCLRR 0x44
32
33/* SYSCFG bit fields */
34#define STM32MP1_SYSCFG_ANASWVDD_MASK BIT(9)
35
36/* SYSCFG capability flags */
37#define HAS_VBOOSTER BIT(0)
38#define HAS_ANASWVDD BIT(1)
39
40/**
41 * struct stm32_adc_common_regs - stm32 common registers
42 * @csr: common status register offset
43 * @ccr: common control register offset
44 * @eoc1_msk: adc1 end of conversion flag in @csr
45 * @eoc2_msk: adc2 end of conversion flag in @csr
46 * @eoc3_msk: adc3 end of conversion flag in @csr
47 * @ier: interrupt enable register offset for each adc
48 * @eocie_msk: end of conversion interrupt enable mask in @ier
49 */
50struct stm32_adc_common_regs {
51 u32 csr;
52 u32 ccr;
53 u32 eoc1_msk;
54 u32 eoc2_msk;
55 u32 eoc3_msk;
56 u32 ier;
57 u32 eocie_msk;
58};
59
60struct stm32_adc_priv;
61
62/**
63 * struct stm32_adc_priv_cfg - stm32 core compatible configuration data
64 * @regs: common registers for all instances
65 * @clk_sel: clock selection routine
66 * @max_clk_rate_hz: maximum analog clock rate (Hz, from datasheet)
67 * @has_syscfg: SYSCFG capability flags
68 * @num_irqs: number of interrupt lines
69 */
70struct stm32_adc_priv_cfg {
71 const struct stm32_adc_common_regs *regs;
72 int (*clk_sel)(struct platform_device *, struct stm32_adc_priv *);
73 u32 max_clk_rate_hz;
74 unsigned int has_syscfg;
75 unsigned int num_irqs;
76};
77
78/**
79 * struct stm32_adc_priv - stm32 ADC core private data
80 * @irq: irq(s) for ADC block
81 * @domain: irq domain reference
82 * @aclk: clock reference for the analog circuitry
83 * @bclk: bus clock common for all ADCs, depends on part used
84 * @max_clk_rate: desired maximum clock rate
85 * @booster: booster supply reference
86 * @vdd: vdd supply reference
87 * @vdda: vdda analog supply reference
88 * @vref: regulator reference
89 * @vdd_uv: vdd supply voltage (microvolts)
90 * @vdda_uv: vdda supply voltage (microvolts)
91 * @cfg: compatible configuration data
92 * @common: common data for all ADC instances
93 * @ccr_bak: backup CCR in low power mode
94 * @syscfg: reference to syscon, system control registers
95 */
96struct 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
114static 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 */
120static 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 */
128static 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 */
174struct stm32h7_adc_ck_spec {
175 u32 ckmode;
176 u32 presc;
177 int div;
178};
179
180static 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
200static int stm32h7_adc_clk_sel(struct platform_device *pdev,
201 struct stm32_adc_priv *priv)
202{
203 u32 ckmode, presc, val;
204 unsigned long rate;
205 int i, div;
206
207 /* stm32h7 bus clock is common for all ADC instances (mandatory) */
208 if (!priv->bclk) {
209 dev_err(&pdev->dev, "No 'bus' clock found\n");
210 return -ENOENT;
211 }
212
213 /*
214 * stm32h7 can use either 'bus' or 'adc' clock for analog circuitry.
215 * So, choice is to have bus clock mandatory and adc clock optional.
216 * If optional 'adc' clock has been found, then try to use it first.
217 */
218 if (priv->aclk) {
219 /*
220 * Asynchronous clock modes (e.g. ckmode == 0)
221 * From spec: PLL output musn't exceed max rate
222 */
223 rate = clk_get_rate(priv->aclk);
224 if (!rate) {
225 dev_err(&pdev->dev, "Invalid adc clock rate: 0\n");
226 return -EINVAL;
227 }
228
229 for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
230 ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
231 presc = stm32h7_adc_ckmodes_spec[i].presc;
232 div = stm32h7_adc_ckmodes_spec[i].div;
233
234 if (ckmode)
235 continue;
236
237 if ((rate / div) <= priv->max_clk_rate)
238 goto out;
239 }
240 }
241
242 /* Synchronous clock modes (e.g. ckmode is 1, 2 or 3) */
243 rate = clk_get_rate(priv->bclk);
244 if (!rate) {
245 dev_err(&pdev->dev, "Invalid bus clock rate: 0\n");
246 return -EINVAL;
247 }
248
249 for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
250 ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
251 presc = stm32h7_adc_ckmodes_spec[i].presc;
252 div = stm32h7_adc_ckmodes_spec[i].div;
253
254 if (!ckmode)
255 continue;
256
257 if ((rate / div) <= priv->max_clk_rate)
258 goto out;
259 }
260
261 dev_err(&pdev->dev, "adc clk selection failed\n");
262 return -EINVAL;
263
264out:
265 /* rate used later by each ADC instance to control BOOST mode */
266 priv->common.rate = rate / div;
267
268 /* Set common clock mode and prescaler */
269 val = readl_relaxed(priv->common.base + STM32H7_ADC_CCR);
270 val &= ~(STM32H7_CKMODE_MASK | STM32H7_PRESC_MASK);
271 val |= ckmode << STM32H7_CKMODE_SHIFT;
272 val |= presc << STM32H7_PRESC_SHIFT;
273 writel_relaxed(val, priv->common.base + STM32H7_ADC_CCR);
274
275 dev_dbg(&pdev->dev, "Using %s clock/%d source at %ld kHz\n",
276 ckmode ? "bus" : "adc", div, priv->common.rate / 1000);
277
278 return 0;
279}
280
281/* STM32F4 common registers definitions */
282static const struct stm32_adc_common_regs stm32f4_adc_common_regs = {
283 .csr = STM32F4_ADC_CSR,
284 .ccr = STM32F4_ADC_CCR,
285 .eoc1_msk = STM32F4_EOC1 | STM32F4_OVR1,
286 .eoc2_msk = STM32F4_EOC2 | STM32F4_OVR2,
287 .eoc3_msk = STM32F4_EOC3 | STM32F4_OVR3,
288 .ier = STM32F4_ADC_CR1,
289 .eocie_msk = STM32F4_EOCIE | STM32F4_OVRIE,
290};
291
292/* STM32H7 common registers definitions */
293static const struct stm32_adc_common_regs stm32h7_adc_common_regs = {
294 .csr = STM32H7_ADC_CSR,
295 .ccr = STM32H7_ADC_CCR,
296 .eoc1_msk = STM32H7_EOC_MST | STM32H7_OVR_MST,
297 .eoc2_msk = STM32H7_EOC_SLV | STM32H7_OVR_SLV,
298 .ier = STM32H7_ADC_IER,
299 .eocie_msk = STM32H7_EOCIE | STM32H7_OVRIE,
300};
301
302static const unsigned int stm32_adc_offset[STM32_ADC_MAX_ADCS] = {
303 0, STM32_ADC_OFFSET, STM32_ADC_OFFSET * 2,
304};
305
306static unsigned int stm32_adc_eoc_enabled(struct stm32_adc_priv *priv,
307 unsigned int adc)
308{
309 u32 ier, offset = stm32_adc_offset[adc];
310
311 ier = readl_relaxed(priv->common.base + offset + priv->cfg->regs->ier);
312
313 return ier & priv->cfg->regs->eocie_msk;
314}
315
316/* ADC common interrupt for all instances */
317static void stm32_adc_irq_handler(struct irq_desc *desc)
318{
319 struct stm32_adc_priv *priv = irq_desc_get_handler_data(desc);
320 struct irq_chip *chip = irq_desc_get_chip(desc);
321 u32 status;
322
323 chained_irq_enter(chip, desc);
324 status = readl_relaxed(priv->common.base + priv->cfg->regs->csr);
325
326 /*
327 * End of conversion may be handled by using IRQ or DMA. There may be a
328 * race here when two conversions complete at the same time on several
329 * ADCs. EOC may be read 'set' for several ADCs, with:
330 * - an ADC configured to use DMA (EOC triggers the DMA request, and
331 * is then automatically cleared by DR read in hardware)
332 * - an ADC configured to use IRQs (EOCIE bit is set. The handler must
333 * be called in this case)
334 * So both EOC status bit in CSR and EOCIE control bit must be checked
335 * before invoking the interrupt handler (e.g. call ISR only for
336 * IRQ-enabled ADCs).
337 */
338 if (status & priv->cfg->regs->eoc1_msk &&
339 stm32_adc_eoc_enabled(priv, 0))
340 generic_handle_irq(irq_find_mapping(priv->domain, 0));
341
342 if (status & priv->cfg->regs->eoc2_msk &&
343 stm32_adc_eoc_enabled(priv, 1))
344 generic_handle_irq(irq_find_mapping(priv->domain, 1));
345
346 if (status & priv->cfg->regs->eoc3_msk &&
347 stm32_adc_eoc_enabled(priv, 2))
348 generic_handle_irq(irq_find_mapping(priv->domain, 2));
349
350 chained_irq_exit(chip, desc);
351};
352
353static int stm32_adc_domain_map(struct irq_domain *d, unsigned int irq,
354 irq_hw_number_t hwirq)
355{
356 irq_set_chip_data(irq, d->host_data);
357 irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_level_irq);
358
359 return 0;
360}
361
362static void stm32_adc_domain_unmap(struct irq_domain *d, unsigned int irq)
363{
364 irq_set_chip_and_handler(irq, NULL, NULL);
365 irq_set_chip_data(irq, NULL);
366}
367
368static const struct irq_domain_ops stm32_adc_domain_ops = {
369 .map = stm32_adc_domain_map,
370 .unmap = stm32_adc_domain_unmap,
371 .xlate = irq_domain_xlate_onecell,
372};
373
374static int stm32_adc_irq_probe(struct platform_device *pdev,
375 struct stm32_adc_priv *priv)
376{
377 struct device_node *np = pdev->dev.of_node;
378 unsigned int i;
379
380 /*
381 * Interrupt(s) must be provided, depending on the compatible:
382 * - stm32f4/h7 shares a common interrupt line.
383 * - stm32mp1, has one line per ADC
384 */
385 for (i = 0; i < priv->cfg->num_irqs; i++) {
386 priv->irq[i] = platform_get_irq(pdev, i);
387 if (priv->irq[i] < 0)
388 return priv->irq[i];
389 }
390
391 priv->domain = irq_domain_add_simple(np, STM32_ADC_MAX_ADCS, 0,
392 &stm32_adc_domain_ops,
393 priv);
394 if (!priv->domain) {
395 dev_err(&pdev->dev, "Failed to add irq domain\n");
396 return -ENOMEM;
397 }
398
399 for (i = 0; i < priv->cfg->num_irqs; i++) {
400 irq_set_chained_handler(priv->irq[i], stm32_adc_irq_handler);
401 irq_set_handler_data(priv->irq[i], priv);
402 }
403
404 return 0;
405}
406
407static void stm32_adc_irq_remove(struct platform_device *pdev,
408 struct stm32_adc_priv *priv)
409{
410 int hwirq;
411 unsigned int i;
412
413 for (hwirq = 0; hwirq < STM32_ADC_MAX_ADCS; hwirq++)
414 irq_dispose_mapping(irq_find_mapping(priv->domain, hwirq));
415 irq_domain_remove(priv->domain);
416
417 for (i = 0; i < priv->cfg->num_irqs; i++)
418 irq_set_chained_handler(priv->irq[i], NULL);
419}
420
421static int stm32_adc_core_switches_supply_en(struct stm32_adc_priv *priv,
422 struct device *dev)
423{
424 int ret;
425
426 /*
427 * On STM32H7 and STM32MP1, the ADC inputs are multiplexed with analog
428 * switches (via PCSEL) which have reduced performances when their
429 * supply is below 2.7V (vdda by default):
430 * - Voltage booster can be used, to get full ADC performances
431 * (increases power consumption).
432 * - Vdd can be used to supply them, if above 2.7V (STM32MP1 only).
433 *
434 * Recommended settings for ANASWVDD and EN_BOOSTER:
435 * - vdda < 2.7V but vdd > 2.7V: ANASWVDD = 1, EN_BOOSTER = 0 (stm32mp1)
436 * - vdda < 2.7V and vdd < 2.7V: ANASWVDD = 0, EN_BOOSTER = 1
437 * - vdda >= 2.7V: ANASWVDD = 0, EN_BOOSTER = 0 (default)
438 */
439 if (priv->vdda_uv < 2700000) {
440 if (priv->syscfg && priv->vdd_uv > 2700000) {
441 ret = regulator_enable(priv->vdd);
442 if (ret < 0) {
443 dev_err(dev, "vdd enable failed %d\n", ret);
444 return ret;
445 }
446
447 ret = regmap_write(priv->syscfg,
448 STM32MP1_SYSCFG_PMCSETR,
449 STM32MP1_SYSCFG_ANASWVDD_MASK);
450 if (ret < 0) {
451 regulator_disable(priv->vdd);
452 dev_err(dev, "vdd select failed, %d\n", ret);
453 return ret;
454 }
455 dev_dbg(dev, "analog switches supplied by vdd\n");
456
457 return 0;
458 }
459
460 if (priv->booster) {
461 /*
462 * This is optional, as this is a trade-off between
463 * analog performance and power consumption.
464 */
465 ret = regulator_enable(priv->booster);
466 if (ret < 0) {
467 dev_err(dev, "booster enable failed %d\n", ret);
468 return ret;
469 }
470 dev_dbg(dev, "analog switches supplied by booster\n");
471
472 return 0;
473 }
474 }
475
476 /* Fallback using vdda (default), nothing to do */
477 dev_dbg(dev, "analog switches supplied by vdda (%d uV)\n",
478 priv->vdda_uv);
479
480 return 0;
481}
482
483static void stm32_adc_core_switches_supply_dis(struct stm32_adc_priv *priv)
484{
485 if (priv->vdda_uv < 2700000) {
486 if (priv->syscfg && priv->vdd_uv > 2700000) {
487 regmap_write(priv->syscfg, STM32MP1_SYSCFG_PMCCLRR,
488 STM32MP1_SYSCFG_ANASWVDD_MASK);
489 regulator_disable(priv->vdd);
490 return;
491 }
492 if (priv->booster)
493 regulator_disable(priv->booster);
494 }
495}
496
497static int stm32_adc_core_hw_start(struct device *dev)
498{
499 struct stm32_adc_common *common = dev_get_drvdata(dev);
500 struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
501 int ret;
502
503 ret = regulator_enable(priv->vdda);
504 if (ret < 0) {
505 dev_err(dev, "vdda enable failed %d\n", ret);
506 return ret;
507 }
508
509 ret = regulator_get_voltage(priv->vdda);
510 if (ret < 0) {
511 dev_err(dev, "vdda get voltage failed, %d\n", ret);
512 goto err_vdda_disable;
513 }
514 priv->vdda_uv = ret;
515
516 ret = stm32_adc_core_switches_supply_en(priv, dev);
517 if (ret < 0)
518 goto err_vdda_disable;
519
520 ret = regulator_enable(priv->vref);
521 if (ret < 0) {
522 dev_err(dev, "vref enable failed\n");
523 goto err_switches_dis;
524 }
525
526 if (priv->bclk) {
527 ret = clk_prepare_enable(priv->bclk);
528 if (ret < 0) {
529 dev_err(dev, "bus clk enable failed\n");
530 goto err_regulator_disable;
531 }
532 }
533
534 if (priv->aclk) {
535 ret = clk_prepare_enable(priv->aclk);
536 if (ret < 0) {
537 dev_err(dev, "adc clk enable failed\n");
538 goto err_bclk_disable;
539 }
540 }
541
542 writel_relaxed(priv->ccr_bak, priv->common.base + priv->cfg->regs->ccr);
543
544 return 0;
545
546err_bclk_disable:
547 if (priv->bclk)
548 clk_disable_unprepare(priv->bclk);
549err_regulator_disable:
550 regulator_disable(priv->vref);
551err_switches_dis:
552 stm32_adc_core_switches_supply_dis(priv);
553err_vdda_disable:
554 regulator_disable(priv->vdda);
555
556 return ret;
557}
558
559static void stm32_adc_core_hw_stop(struct device *dev)
560{
561 struct stm32_adc_common *common = dev_get_drvdata(dev);
562 struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
563
564 /* Backup CCR that may be lost (depends on power state to achieve) */
565 priv->ccr_bak = readl_relaxed(priv->common.base + priv->cfg->regs->ccr);
566 if (priv->aclk)
567 clk_disable_unprepare(priv->aclk);
568 if (priv->bclk)
569 clk_disable_unprepare(priv->bclk);
570 regulator_disable(priv->vref);
571 stm32_adc_core_switches_supply_dis(priv);
572 regulator_disable(priv->vdda);
573}
574
575static int stm32_adc_core_switches_probe(struct device *dev,
576 struct stm32_adc_priv *priv)
577{
578 struct device_node *np = dev->of_node;
579 int ret;
580
581 /* Analog switches supply can be controlled by syscfg (optional) */
582 priv->syscfg = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
583 if (IS_ERR(priv->syscfg)) {
584 ret = PTR_ERR(priv->syscfg);
585 if (ret != -ENODEV) {
586 if (ret != -EPROBE_DEFER)
587 dev_err(dev, "Can't probe syscfg: %d\n", ret);
588 return ret;
589 }
590 priv->syscfg = NULL;
591 }
592
593 /* Booster can be used to supply analog switches (optional) */
594 if (priv->cfg->has_syscfg & HAS_VBOOSTER &&
595 of_property_read_bool(np, "booster-supply")) {
596 priv->booster = devm_regulator_get_optional(dev, "booster");
597 if (IS_ERR(priv->booster)) {
598 ret = PTR_ERR(priv->booster);
599 if (ret != -ENODEV) {
600 if (ret != -EPROBE_DEFER)
601 dev_err(dev, "can't get booster %d\n",
602 ret);
603 return ret;
604 }
605 priv->booster = NULL;
606 }
607 }
608
609 /* Vdd can be used to supply analog switches (optional) */
610 if (priv->cfg->has_syscfg & HAS_ANASWVDD &&
611 of_property_read_bool(np, "vdd-supply")) {
612 priv->vdd = devm_regulator_get_optional(dev, "vdd");
613 if (IS_ERR(priv->vdd)) {
614 ret = PTR_ERR(priv->vdd);
615 if (ret != -ENODEV) {
616 if (ret != -EPROBE_DEFER)
617 dev_err(dev, "can't get vdd %d\n", ret);
618 return ret;
619 }
620 priv->vdd = NULL;
621 }
622 }
623
624 if (priv->vdd) {
625 ret = regulator_enable(priv->vdd);
626 if (ret < 0) {
627 dev_err(dev, "vdd enable failed %d\n", ret);
628 return ret;
629 }
630
631 ret = regulator_get_voltage(priv->vdd);
632 if (ret < 0) {
633 dev_err(dev, "vdd get voltage failed %d\n", ret);
634 regulator_disable(priv->vdd);
635 return ret;
636 }
637 priv->vdd_uv = ret;
638
639 regulator_disable(priv->vdd);
640 }
641
642 return 0;
643}
644
645static int stm32_adc_probe(struct platform_device *pdev)
646{
647 struct stm32_adc_priv *priv;
648 struct device *dev = &pdev->dev;
649 struct device_node *np = pdev->dev.of_node;
650 struct resource *res;
651 u32 max_rate;
652 int ret;
653
654 if (!pdev->dev.of_node)
655 return -ENODEV;
656
657 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
658 if (!priv)
659 return -ENOMEM;
660 platform_set_drvdata(pdev, &priv->common);
661
662 priv->cfg = (const struct stm32_adc_priv_cfg *)
663 of_match_device(dev->driver->of_match_table, dev)->data;
664
665 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
666 priv->common.base = devm_ioremap_resource(&pdev->dev, res);
667 if (IS_ERR(priv->common.base))
668 return PTR_ERR(priv->common.base);
669 priv->common.phys_base = res->start;
670
671 priv->vdda = devm_regulator_get(&pdev->dev, "vdda");
672 if (IS_ERR(priv->vdda)) {
673 ret = PTR_ERR(priv->vdda);
674 if (ret != -EPROBE_DEFER)
675 dev_err(&pdev->dev, "vdda get failed, %d\n", ret);
676 return ret;
677 }
678
679 priv->vref = devm_regulator_get(&pdev->dev, "vref");
680 if (IS_ERR(priv->vref)) {
681 ret = PTR_ERR(priv->vref);
682 if (ret != -EPROBE_DEFER)
683 dev_err(&pdev->dev, "vref get failed, %d\n", ret);
684 return ret;
685 }
686
687 priv->aclk = devm_clk_get(&pdev->dev, "adc");
688 if (IS_ERR(priv->aclk)) {
689 ret = PTR_ERR(priv->aclk);
690 if (ret != -ENOENT) {
691 if (ret != -EPROBE_DEFER)
692 dev_err(&pdev->dev, "Can't get 'adc' clock\n");
693 return ret;
694 }
695 priv->aclk = NULL;
696 }
697
698 priv->bclk = devm_clk_get(&pdev->dev, "bus");
699 if (IS_ERR(priv->bclk)) {
700 ret = PTR_ERR(priv->bclk);
701 if (ret != -ENOENT) {
702 if (ret != -EPROBE_DEFER)
703 dev_err(&pdev->dev, "Can't get 'bus' clock\n");
704 return ret;
705 }
706 priv->bclk = NULL;
707 }
708
709 ret = stm32_adc_core_switches_probe(dev, priv);
710 if (ret)
711 return ret;
712
713 pm_runtime_get_noresume(dev);
714 pm_runtime_set_active(dev);
715 pm_runtime_set_autosuspend_delay(dev, STM32_ADC_CORE_SLEEP_DELAY_MS);
716 pm_runtime_use_autosuspend(dev);
717 pm_runtime_enable(dev);
718
719 ret = stm32_adc_core_hw_start(dev);
720 if (ret)
721 goto err_pm_stop;
722
723 ret = regulator_get_voltage(priv->vref);
724 if (ret < 0) {
725 dev_err(&pdev->dev, "vref get voltage failed, %d\n", ret);
726 goto err_hw_stop;
727 }
728 priv->common.vref_mv = ret / 1000;
729 dev_dbg(&pdev->dev, "vref+=%dmV\n", priv->common.vref_mv);
730
731 ret = of_property_read_u32(pdev->dev.of_node, "st,max-clk-rate-hz",
732 &max_rate);
733 if (!ret)
734 priv->max_clk_rate = min(max_rate, priv->cfg->max_clk_rate_hz);
735 else
736 priv->max_clk_rate = priv->cfg->max_clk_rate_hz;
737
738 ret = priv->cfg->clk_sel(pdev, priv);
739 if (ret < 0)
740 goto err_hw_stop;
741
742 ret = stm32_adc_irq_probe(pdev, priv);
743 if (ret < 0)
744 goto err_hw_stop;
745
746 ret = of_platform_populate(np, NULL, NULL, &pdev->dev);
747 if (ret < 0) {
748 dev_err(&pdev->dev, "failed to populate DT children\n");
749 goto err_irq_remove;
750 }
751
752 pm_runtime_mark_last_busy(dev);
753 pm_runtime_put_autosuspend(dev);
754
755 return 0;
756
757err_irq_remove:
758 stm32_adc_irq_remove(pdev, priv);
759err_hw_stop:
760 stm32_adc_core_hw_stop(dev);
761err_pm_stop:
762 pm_runtime_disable(dev);
763 pm_runtime_set_suspended(dev);
764 pm_runtime_put_noidle(dev);
765
766 return ret;
767}
768
769static int stm32_adc_remove(struct platform_device *pdev)
770{
771 struct stm32_adc_common *common = platform_get_drvdata(pdev);
772 struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
773
774 pm_runtime_get_sync(&pdev->dev);
775 of_platform_depopulate(&pdev->dev);
776 stm32_adc_irq_remove(pdev, priv);
777 stm32_adc_core_hw_stop(&pdev->dev);
778 pm_runtime_disable(&pdev->dev);
779 pm_runtime_set_suspended(&pdev->dev);
780 pm_runtime_put_noidle(&pdev->dev);
781
782 return 0;
783}
784
785#if defined(CONFIG_PM)
786static int stm32_adc_core_runtime_suspend(struct device *dev)
787{
788 stm32_adc_core_hw_stop(dev);
789
790 return 0;
791}
792
793static int stm32_adc_core_runtime_resume(struct device *dev)
794{
795 return stm32_adc_core_hw_start(dev);
796}
797#endif
798
799static const struct dev_pm_ops stm32_adc_core_pm_ops = {
800 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
801 pm_runtime_force_resume)
802 SET_RUNTIME_PM_OPS(stm32_adc_core_runtime_suspend,
803 stm32_adc_core_runtime_resume,
804 NULL)
805};
806
807static const struct stm32_adc_priv_cfg stm32f4_adc_priv_cfg = {
808 .regs = &stm32f4_adc_common_regs,
809 .clk_sel = stm32f4_adc_clk_sel,
810 .max_clk_rate_hz = 36000000,
811 .num_irqs = 1,
812};
813
814static const struct stm32_adc_priv_cfg stm32h7_adc_priv_cfg = {
815 .regs = &stm32h7_adc_common_regs,
816 .clk_sel = stm32h7_adc_clk_sel,
817 .max_clk_rate_hz = 36000000,
818 .has_syscfg = HAS_VBOOSTER,
819 .num_irqs = 1,
820};
821
822static const struct stm32_adc_priv_cfg stm32mp1_adc_priv_cfg = {
823 .regs = &stm32h7_adc_common_regs,
824 .clk_sel = stm32h7_adc_clk_sel,
825 .max_clk_rate_hz = 40000000,
826 .has_syscfg = HAS_VBOOSTER | HAS_ANASWVDD,
827 .num_irqs = 2,
828};
829
830static const struct of_device_id stm32_adc_of_match[] = {
831 {
832 .compatible = "st,stm32f4-adc-core",
833 .data = (void *)&stm32f4_adc_priv_cfg
834 }, {
835 .compatible = "st,stm32h7-adc-core",
836 .data = (void *)&stm32h7_adc_priv_cfg
837 }, {
838 .compatible = "st,stm32mp1-adc-core",
839 .data = (void *)&stm32mp1_adc_priv_cfg
840 }, {
841 },
842};
843MODULE_DEVICE_TABLE(of, stm32_adc_of_match);
844
845static struct platform_driver stm32_adc_driver = {
846 .probe = stm32_adc_probe,
847 .remove = stm32_adc_remove,
848 .driver = {
849 .name = "stm32-adc-core",
850 .of_match_table = stm32_adc_of_match,
851 .pm = &stm32_adc_core_pm_ops,
852 },
853};
854module_platform_driver(stm32_adc_driver);
855
856MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
857MODULE_DESCRIPTION("STMicroelectronics STM32 ADC core driver");
858MODULE_LICENSE("GPL v2");
859MODULE_ALIAS("platform:stm32-adc-core");
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 */
54struct 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
63struct 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 */
75struct 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 */
104struct 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
123static 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 */
129static 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 */
137static 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 */
183struct stm32h7_adc_ck_spec {
184 u32 ckmode;
185 u32 presc;
186 int div;
187};
188
189static 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
209static 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
292out:
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 */
310static 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 */
320static 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 */
330static 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
339static const unsigned int stm32_adc_offset[STM32_ADC_MAX_ADCS] = {
340 0, STM32_ADC_OFFSET, STM32_ADC_OFFSET * 2,
341};
342
343static 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 */
354static 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
386static 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
395static 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
401static 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
407static 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
440static 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
454static 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
516static 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
530static 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
575err_bclk_disable:
576 clk_disable_unprepare(priv->bclk);
577err_regulator_disable:
578 regulator_disable(priv->vref);
579err_switches_dis:
580 stm32_adc_core_switches_supply_dis(priv);
581err_vdda_disable:
582 regulator_disable(priv->vdda);
583
584 return ret;
585}
586
587static 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
601static 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
664static 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
707static 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
805err_irq_remove:
806 stm32_adc_irq_remove(pdev, priv);
807err_hw_stop:
808 stm32_adc_core_hw_stop(dev);
809err_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
817static 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
831static int stm32_adc_core_runtime_suspend(struct device *dev)
832{
833 stm32_adc_core_hw_stop(dev);
834
835 return 0;
836}
837
838static int stm32_adc_core_runtime_resume(struct device *dev)
839{
840 return stm32_adc_core_hw_start(dev);
841}
842
843static int stm32_adc_core_runtime_idle(struct device *dev)
844{
845 pm_runtime_mark_last_busy(dev);
846
847 return 0;
848}
849
850static 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
855static 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
863static 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
872static 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
881static 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
889static 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};
905MODULE_DEVICE_TABLE(of, stm32_adc_of_match);
906
907static struct platform_driver stm32_adc_driver = {
908 .probe = stm32_adc_probe,
909 .remove = 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};
916module_platform_driver(stm32_adc_driver);
917
918MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
919MODULE_DESCRIPTION("STMicroelectronics STM32 ADC core driver");
920MODULE_LICENSE("GPL v2");
921MODULE_ALIAS("platform:stm32-adc-core");