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
to_stm32_adc_priv(struct stm32_adc_common * com)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 */
stm32f4_adc_clk_sel(struct platform_device * pdev,struct stm32_adc_priv * priv)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
stm32h7_adc_clk_sel(struct platform_device * pdev,struct stm32_adc_priv * priv)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
stm32_adc_eoc_enabled(struct stm32_adc_priv * priv,unsigned int adc)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 */
stm32_adc_irq_handler(struct irq_desc * desc)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
stm32_adc_domain_map(struct irq_domain * d,unsigned int irq,irq_hw_number_t hwirq)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
stm32_adc_domain_unmap(struct irq_domain * d,unsigned int irq)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
stm32_adc_irq_probe(struct platform_device * pdev,struct stm32_adc_priv * priv)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_create_simple(of_fwnode_handle(np),
425 STM32_ADC_MAX_ADCS, 0,
426 &stm32_adc_domain_ops,
427 priv);
428 if (!priv->domain) {
429 dev_err(&pdev->dev, "Failed to add irq domain\n");
430 return -ENOMEM;
431 }
432
433 for (i = 0; i < priv->cfg->num_irqs; i++) {
434 irq_set_chained_handler(priv->irq[i], stm32_adc_irq_handler);
435 irq_set_handler_data(priv->irq[i], priv);
436 }
437
438 return 0;
439 }
440
stm32_adc_irq_remove(struct platform_device * pdev,struct stm32_adc_priv * priv)441 static void stm32_adc_irq_remove(struct platform_device *pdev,
442 struct stm32_adc_priv *priv)
443 {
444 int hwirq;
445 unsigned int i;
446
447 for (hwirq = 0; hwirq < priv->nb_adc_max; hwirq++)
448 irq_dispose_mapping(irq_find_mapping(priv->domain, hwirq));
449 irq_domain_remove(priv->domain);
450
451 for (i = 0; i < priv->cfg->num_irqs; i++)
452 irq_set_chained_handler(priv->irq[i], NULL);
453 }
454
stm32_adc_core_switches_supply_en(struct stm32_adc_priv * priv,struct device * dev)455 static int stm32_adc_core_switches_supply_en(struct stm32_adc_priv *priv,
456 struct device *dev)
457 {
458 int ret;
459
460 /*
461 * On STM32H7 and STM32MP1, the ADC inputs are multiplexed with analog
462 * switches (via PCSEL) which have reduced performances when their
463 * supply is below 2.7V (vdda by default):
464 * - Voltage booster can be used, to get full ADC performances
465 * (increases power consumption).
466 * - Vdd can be used to supply them, if above 2.7V (STM32MP1 only).
467 *
468 * Recommended settings for ANASWVDD and EN_BOOSTER:
469 * - vdda < 2.7V but vdd > 2.7V: ANASWVDD = 1, EN_BOOSTER = 0 (stm32mp1)
470 * - vdda < 2.7V and vdd < 2.7V: ANASWVDD = 0, EN_BOOSTER = 1
471 * - vdda >= 2.7V: ANASWVDD = 0, EN_BOOSTER = 0 (default)
472 */
473 if (priv->vdda_uv < 2700000) {
474 if (priv->syscfg && priv->vdd_uv > 2700000) {
475 ret = regulator_enable(priv->vdd);
476 if (ret < 0) {
477 dev_err(dev, "vdd enable failed %d\n", ret);
478 return ret;
479 }
480
481 ret = regmap_write(priv->syscfg,
482 STM32MP1_SYSCFG_PMCSETR,
483 STM32MP1_SYSCFG_ANASWVDD_MASK);
484 if (ret < 0) {
485 regulator_disable(priv->vdd);
486 dev_err(dev, "vdd select failed, %d\n", ret);
487 return ret;
488 }
489 dev_dbg(dev, "analog switches supplied by vdd\n");
490
491 return 0;
492 }
493
494 if (priv->booster) {
495 /*
496 * This is optional, as this is a trade-off between
497 * analog performance and power consumption.
498 */
499 ret = regulator_enable(priv->booster);
500 if (ret < 0) {
501 dev_err(dev, "booster enable failed %d\n", ret);
502 return ret;
503 }
504 dev_dbg(dev, "analog switches supplied by booster\n");
505
506 return 0;
507 }
508 }
509
510 /* Fallback using vdda (default), nothing to do */
511 dev_dbg(dev, "analog switches supplied by vdda (%d uV)\n",
512 priv->vdda_uv);
513
514 return 0;
515 }
516
stm32_adc_core_switches_supply_dis(struct stm32_adc_priv * priv)517 static void stm32_adc_core_switches_supply_dis(struct stm32_adc_priv *priv)
518 {
519 if (priv->vdda_uv < 2700000) {
520 if (priv->syscfg && priv->vdd_uv > 2700000) {
521 regmap_write(priv->syscfg, STM32MP1_SYSCFG_PMCCLRR,
522 STM32MP1_SYSCFG_ANASWVDD_MASK);
523 regulator_disable(priv->vdd);
524 return;
525 }
526 if (priv->booster)
527 regulator_disable(priv->booster);
528 }
529 }
530
stm32_adc_core_hw_start(struct device * dev)531 static int stm32_adc_core_hw_start(struct device *dev)
532 {
533 struct stm32_adc_common *common = dev_get_drvdata(dev);
534 struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
535 int ret;
536
537 ret = regulator_enable(priv->vdda);
538 if (ret < 0) {
539 dev_err(dev, "vdda enable failed %d\n", ret);
540 return ret;
541 }
542
543 ret = regulator_get_voltage(priv->vdda);
544 if (ret < 0) {
545 dev_err(dev, "vdda get voltage failed, %d\n", ret);
546 goto err_vdda_disable;
547 }
548 priv->vdda_uv = ret;
549
550 ret = stm32_adc_core_switches_supply_en(priv, dev);
551 if (ret < 0)
552 goto err_vdda_disable;
553
554 ret = regulator_enable(priv->vref);
555 if (ret < 0) {
556 dev_err(dev, "vref enable failed\n");
557 goto err_switches_dis;
558 }
559
560 ret = clk_prepare_enable(priv->bclk);
561 if (ret < 0) {
562 dev_err(dev, "bus clk enable failed\n");
563 goto err_regulator_disable;
564 }
565
566 ret = clk_prepare_enable(priv->aclk);
567 if (ret < 0) {
568 dev_err(dev, "adc clk enable failed\n");
569 goto err_bclk_disable;
570 }
571
572 writel_relaxed(priv->ccr_bak, priv->common.base + priv->cfg->regs->ccr);
573
574 return 0;
575
576 err_bclk_disable:
577 clk_disable_unprepare(priv->bclk);
578 err_regulator_disable:
579 regulator_disable(priv->vref);
580 err_switches_dis:
581 stm32_adc_core_switches_supply_dis(priv);
582 err_vdda_disable:
583 regulator_disable(priv->vdda);
584
585 return ret;
586 }
587
stm32_adc_core_hw_stop(struct device * dev)588 static void stm32_adc_core_hw_stop(struct device *dev)
589 {
590 struct stm32_adc_common *common = dev_get_drvdata(dev);
591 struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
592
593 /* Backup CCR that may be lost (depends on power state to achieve) */
594 priv->ccr_bak = readl_relaxed(priv->common.base + priv->cfg->regs->ccr);
595 clk_disable_unprepare(priv->aclk);
596 clk_disable_unprepare(priv->bclk);
597 regulator_disable(priv->vref);
598 stm32_adc_core_switches_supply_dis(priv);
599 regulator_disable(priv->vdda);
600 }
601
stm32_adc_core_switches_probe(struct device * dev,struct stm32_adc_priv * priv)602 static int stm32_adc_core_switches_probe(struct device *dev,
603 struct stm32_adc_priv *priv)
604 {
605 struct device_node *np = dev->of_node;
606 int ret;
607
608 /* Analog switches supply can be controlled by syscfg (optional) */
609 priv->syscfg = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
610 if (IS_ERR(priv->syscfg)) {
611 ret = PTR_ERR(priv->syscfg);
612 if (ret != -ENODEV)
613 return dev_err_probe(dev, ret, "Can't probe syscfg\n");
614
615 priv->syscfg = NULL;
616 }
617
618 /* Booster can be used to supply analog switches (optional) */
619 if (priv->cfg->has_syscfg & HAS_VBOOSTER) {
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 priv->vdd = devm_regulator_get_optional(dev, "vdd");
633 if (IS_ERR(priv->vdd)) {
634 ret = PTR_ERR(priv->vdd);
635 if (ret != -ENODEV)
636 return dev_err_probe(dev, ret, "can't get vdd\n");
637
638 priv->vdd = NULL;
639 }
640 }
641
642 if (priv->vdd) {
643 ret = regulator_enable(priv->vdd);
644 if (ret < 0) {
645 dev_err(dev, "vdd enable failed %d\n", ret);
646 return ret;
647 }
648
649 ret = regulator_get_voltage(priv->vdd);
650 if (ret < 0) {
651 dev_err(dev, "vdd get voltage failed %d\n", ret);
652 regulator_disable(priv->vdd);
653 return ret;
654 }
655 priv->vdd_uv = ret;
656
657 regulator_disable(priv->vdd);
658 }
659
660 return 0;
661 }
662
stm32_adc_probe_identification(struct platform_device * pdev,struct stm32_adc_priv * priv)663 static int stm32_adc_probe_identification(struct platform_device *pdev,
664 struct stm32_adc_priv *priv)
665 {
666 struct device_node *np = pdev->dev.of_node;
667 struct device_node *child;
668 const char *compat;
669 int ret, count = 0;
670 u32 id, val;
671
672 if (!priv->cfg->ipid)
673 return 0;
674
675 id = FIELD_GET(STM32MP1_IPIDR_MASK,
676 readl_relaxed(priv->common.base + STM32MP1_ADC_IPDR));
677 if (id != priv->cfg->ipid) {
678 dev_err(&pdev->dev, "Unexpected IP version: 0x%x", id);
679 return -EINVAL;
680 }
681
682 for_each_child_of_node(np, child) {
683 ret = of_property_read_string(child, "compatible", &compat);
684 if (ret)
685 continue;
686 /* Count child nodes with stm32 adc compatible */
687 if (strstr(compat, "st,stm32") && strstr(compat, "adc"))
688 count++;
689 }
690
691 val = readl_relaxed(priv->common.base + STM32MP1_ADC_HWCFGR0);
692 priv->nb_adc_max = FIELD_GET(STM32MP1_ADCNUM_MASK, val);
693 if (count > priv->nb_adc_max) {
694 dev_err(&pdev->dev, "Unexpected child number: %d", count);
695 return -EINVAL;
696 }
697
698 val = readl_relaxed(priv->common.base + STM32MP1_ADC_VERR);
699 dev_dbg(&pdev->dev, "ADC version: %lu.%lu\n",
700 FIELD_GET(STM32MP1_MAJREV_MASK, val),
701 FIELD_GET(STM32MP1_MINREV_MASK, val));
702
703 return 0;
704 }
705
stm32_adc_probe(struct platform_device * pdev)706 static int stm32_adc_probe(struct platform_device *pdev)
707 {
708 struct stm32_adc_priv *priv;
709 struct device *dev = &pdev->dev;
710 struct device_node *np = pdev->dev.of_node;
711 struct resource *res;
712 u32 max_rate;
713 int ret;
714
715 if (!pdev->dev.of_node)
716 return -ENODEV;
717
718 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
719 if (!priv)
720 return -ENOMEM;
721 platform_set_drvdata(pdev, &priv->common);
722
723 priv->cfg = device_get_match_data(dev);
724 priv->nb_adc_max = priv->cfg->num_adcs;
725 spin_lock_init(&priv->common.lock);
726
727 priv->common.base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
728 if (IS_ERR(priv->common.base))
729 return PTR_ERR(priv->common.base);
730 priv->common.phys_base = res->start;
731
732 priv->vdda = devm_regulator_get(&pdev->dev, "vdda");
733 if (IS_ERR(priv->vdda))
734 return dev_err_probe(&pdev->dev, PTR_ERR(priv->vdda),
735 "vdda get failed\n");
736
737 priv->vref = devm_regulator_get(&pdev->dev, "vref");
738 if (IS_ERR(priv->vref))
739 return dev_err_probe(&pdev->dev, PTR_ERR(priv->vref),
740 "vref get failed\n");
741
742 priv->aclk = devm_clk_get_optional(&pdev->dev, "adc");
743 if (IS_ERR(priv->aclk))
744 return dev_err_probe(&pdev->dev, PTR_ERR(priv->aclk),
745 "Can't get 'adc' clock\n");
746
747 priv->bclk = devm_clk_get_optional(&pdev->dev, "bus");
748 if (IS_ERR(priv->bclk))
749 return dev_err_probe(&pdev->dev, PTR_ERR(priv->bclk),
750 "Can't get 'bus' clock\n");
751
752 ret = stm32_adc_core_switches_probe(dev, priv);
753 if (ret)
754 return ret;
755
756 pm_runtime_get_noresume(dev);
757 pm_runtime_set_active(dev);
758 pm_runtime_set_autosuspend_delay(dev, STM32_ADC_CORE_SLEEP_DELAY_MS);
759 pm_runtime_use_autosuspend(dev);
760 pm_runtime_enable(dev);
761
762 ret = stm32_adc_core_hw_start(dev);
763 if (ret)
764 goto err_pm_stop;
765
766 ret = stm32_adc_probe_identification(pdev, priv);
767 if (ret < 0)
768 goto err_hw_stop;
769
770 ret = regulator_get_voltage(priv->vref);
771 if (ret < 0) {
772 dev_err(&pdev->dev, "vref get voltage failed, %d\n", ret);
773 goto err_hw_stop;
774 }
775 priv->common.vref_mv = ret / 1000;
776 dev_dbg(&pdev->dev, "vref+=%dmV\n", priv->common.vref_mv);
777
778 ret = of_property_read_u32(pdev->dev.of_node, "st,max-clk-rate-hz",
779 &max_rate);
780 if (!ret)
781 priv->max_clk_rate = min(max_rate, priv->cfg->max_clk_rate_hz);
782 else
783 priv->max_clk_rate = priv->cfg->max_clk_rate_hz;
784
785 ret = priv->cfg->clk_sel(pdev, priv);
786 if (ret < 0)
787 goto err_hw_stop;
788
789 ret = stm32_adc_irq_probe(pdev, priv);
790 if (ret < 0)
791 goto err_hw_stop;
792
793 ret = of_platform_populate(np, NULL, NULL, &pdev->dev);
794 if (ret < 0) {
795 dev_err(&pdev->dev, "failed to populate DT children\n");
796 goto err_irq_remove;
797 }
798
799 pm_runtime_mark_last_busy(dev);
800 pm_runtime_put_autosuspend(dev);
801
802 return 0;
803
804 err_irq_remove:
805 stm32_adc_irq_remove(pdev, priv);
806 err_hw_stop:
807 stm32_adc_core_hw_stop(dev);
808 err_pm_stop:
809 pm_runtime_disable(dev);
810 pm_runtime_set_suspended(dev);
811 pm_runtime_put_noidle(dev);
812
813 return ret;
814 }
815
stm32_adc_remove(struct platform_device * pdev)816 static void stm32_adc_remove(struct platform_device *pdev)
817 {
818 struct stm32_adc_common *common = platform_get_drvdata(pdev);
819 struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
820
821 pm_runtime_get_sync(&pdev->dev);
822 of_platform_depopulate(&pdev->dev);
823 stm32_adc_irq_remove(pdev, priv);
824 stm32_adc_core_hw_stop(&pdev->dev);
825 pm_runtime_disable(&pdev->dev);
826 pm_runtime_set_suspended(&pdev->dev);
827 pm_runtime_put_noidle(&pdev->dev);
828 }
829
stm32_adc_core_runtime_suspend(struct device * dev)830 static int stm32_adc_core_runtime_suspend(struct device *dev)
831 {
832 stm32_adc_core_hw_stop(dev);
833
834 return 0;
835 }
836
stm32_adc_core_runtime_resume(struct device * dev)837 static int stm32_adc_core_runtime_resume(struct device *dev)
838 {
839 return stm32_adc_core_hw_start(dev);
840 }
841
stm32_adc_core_runtime_idle(struct device * dev)842 static int stm32_adc_core_runtime_idle(struct device *dev)
843 {
844 pm_runtime_mark_last_busy(dev);
845
846 return 0;
847 }
848
849 static DEFINE_RUNTIME_DEV_PM_OPS(stm32_adc_core_pm_ops,
850 stm32_adc_core_runtime_suspend,
851 stm32_adc_core_runtime_resume,
852 stm32_adc_core_runtime_idle);
853
854 static const struct stm32_adc_priv_cfg stm32f4_adc_priv_cfg = {
855 .regs = &stm32f4_adc_common_regs,
856 .clk_sel = stm32f4_adc_clk_sel,
857 .max_clk_rate_hz = 36000000,
858 .num_irqs = 1,
859 .num_adcs = 3,
860 };
861
862 static const struct stm32_adc_priv_cfg stm32h7_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,
867 .num_irqs = 1,
868 .num_adcs = 2,
869 };
870
871 static const struct stm32_adc_priv_cfg stm32mp1_adc_priv_cfg = {
872 .regs = &stm32h7_adc_common_regs,
873 .clk_sel = stm32h7_adc_clk_sel,
874 .max_clk_rate_hz = 36000000,
875 .has_syscfg = HAS_VBOOSTER | HAS_ANASWVDD,
876 .ipid = STM32MP15_IPIDR_NUMBER,
877 .num_irqs = 2,
878 };
879
880 static const struct stm32_adc_priv_cfg stm32mp13_adc_priv_cfg = {
881 .regs = &stm32mp13_adc_common_regs,
882 .clk_sel = stm32h7_adc_clk_sel,
883 .max_clk_rate_hz = 75 * HZ_PER_MHZ,
884 .ipid = STM32MP13_IPIDR_NUMBER,
885 .num_irqs = 1,
886 };
887
888 static const struct of_device_id stm32_adc_of_match[] = {
889 {
890 .compatible = "st,stm32f4-adc-core",
891 .data = (void *)&stm32f4_adc_priv_cfg
892 }, {
893 .compatible = "st,stm32h7-adc-core",
894 .data = (void *)&stm32h7_adc_priv_cfg
895 }, {
896 .compatible = "st,stm32mp1-adc-core",
897 .data = (void *)&stm32mp1_adc_priv_cfg
898 }, {
899 .compatible = "st,stm32mp13-adc-core",
900 .data = (void *)&stm32mp13_adc_priv_cfg
901 }, {
902 },
903 };
904 MODULE_DEVICE_TABLE(of, stm32_adc_of_match);
905
906 static struct platform_driver stm32_adc_driver = {
907 .probe = stm32_adc_probe,
908 .remove = stm32_adc_remove,
909 .driver = {
910 .name = "stm32-adc-core",
911 .of_match_table = stm32_adc_of_match,
912 .pm = pm_ptr(&stm32_adc_core_pm_ops),
913 },
914 };
915 module_platform_driver(stm32_adc_driver);
916
917 MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
918 MODULE_DESCRIPTION("STMicroelectronics STM32 ADC core driver");
919 MODULE_LICENSE("GPL v2");
920 MODULE_ALIAS("platform:stm32-adc-core");
921