treewide: remove redundant IS_ERR() before error code check

[linux/fpc-iii.git] / drivers / iio / adc / stm32-adc-core.c

// SPDX-License-Identifier: GPL-2.0
/*
 * This file is part of STM32 ADC driver
 *
 * Copyright (C) 2016, STMicroelectronics - All Rights Reserved
 * Author: Fabrice Gasnier <fabrice.gasnier@st.com>.
 *
 * Inspired from: fsl-imx25-tsadc
 *
 */

#include <linux/clk.h>
#include <linux/interrupt.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/irqdesc.h>
#include <linux/irqdomain.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>

#include "stm32-adc-core.h"

#define STM32_ADC_CORE_SLEEP_DELAY_MS   2000

/* SYSCFG registers */
#define STM32MP1_SYSCFG_PMCSETR         0x04
#define STM32MP1_SYSCFG_PMCCLRR         0x44

/* SYSCFG bit fields */
#define STM32MP1_SYSCFG_ANASWVDD_MASK   BIT(9)

/* SYSCFG capability flags */
#define HAS_VBOOSTER            BIT(0)
#define HAS_ANASWVDD            BIT(1)

/**
 * struct stm32_adc_common_regs - stm32 common registers
 * @csr:        common status register offset
 * @ccr:        common control register offset
 * @eoc1_msk:   adc1 end of conversion flag in @csr
 * @eoc2_msk:   adc2 end of conversion flag in @csr
 * @eoc3_msk:   adc3 end of conversion flag in @csr
 * @ier:        interrupt enable register offset for each adc
 * @eocie_msk:  end of conversion interrupt enable mask in @ier
 */
struct stm32_adc_common_regs {
        u32 csr;
        u32 ccr;
        u32 eoc1_msk;
        u32 eoc2_msk;
        u32 eoc3_msk;
        u32 ier;
        u32 eocie_msk;
};

struct stm32_adc_priv;

/**
 * struct stm32_adc_priv_cfg - stm32 core compatible configuration data
 * @regs:       common registers for all instances
 * @clk_sel:    clock selection routine
 * @max_clk_rate_hz: maximum analog clock rate (Hz, from datasheet)
 * @has_syscfg: SYSCFG capability flags
 */
struct stm32_adc_priv_cfg {
        const struct stm32_adc_common_regs *regs;
        int (*clk_sel)(struct platform_device *, struct stm32_adc_priv *);
        u32 max_clk_rate_hz;
        unsigned int has_syscfg;
};

/**
 * struct stm32_adc_priv - stm32 ADC core private data
 * @irq:                irq(s) for ADC block
 * @domain:             irq domain reference
 * @aclk:               clock reference for the analog circuitry
 * @bclk:               bus clock common for all ADCs, depends on part used
 * @max_clk_rate:       desired maximum clock rate
 * @booster:            booster supply reference
 * @vdd:                vdd supply reference
 * @vdda:               vdda analog supply reference
 * @vref:               regulator reference
 * @vdd_uv:             vdd supply voltage (microvolts)
 * @vdda_uv:            vdda supply voltage (microvolts)
 * @cfg:                compatible configuration data
 * @common:             common data for all ADC instances
 * @ccr_bak:            backup CCR in low power mode
 * @syscfg:             reference to syscon, system control registers
 */
struct stm32_adc_priv {
        int                             irq[STM32_ADC_MAX_ADCS];
        struct irq_domain               *domain;
        struct clk                      *aclk;
        struct clk                      *bclk;
        u32                             max_clk_rate;
        struct regulator                *booster;
        struct regulator                *vdd;
        struct regulator                *vdda;
        struct regulator                *vref;
        int                             vdd_uv;
        int                             vdda_uv;
        const struct stm32_adc_priv_cfg *cfg;
        struct stm32_adc_common         common;
        u32                             ccr_bak;
        struct regmap                   *syscfg;
};

static struct stm32_adc_priv *to_stm32_adc_priv(struct stm32_adc_common *com)
{
        return container_of(com, struct stm32_adc_priv, common);
}

/* STM32F4 ADC internal common clock prescaler division ratios */
static int stm32f4_pclk_div[] = {2, 4, 6, 8};

/**
 * stm32f4_adc_clk_sel() - Select stm32f4 ADC common clock prescaler
 * @pdev: platform device
 * @priv: stm32 ADC core private data
 * Select clock prescaler used for analog conversions, before using ADC.
 */
static int stm32f4_adc_clk_sel(struct platform_device *pdev,
                               struct stm32_adc_priv *priv)
{
        unsigned long rate;
        u32 val;
        int i;

        /* stm32f4 has one clk input for analog (mandatory), enforce it here */
        if (!priv->aclk) {
                dev_err(&pdev->dev, "No 'adc' clock found\n");
                return -ENOENT;
        }

        rate = clk_get_rate(priv->aclk);
        if (!rate) {
                dev_err(&pdev->dev, "Invalid clock rate: 0\n");
                return -EINVAL;
        }

        for (i = 0; i < ARRAY_SIZE(stm32f4_pclk_div); i++) {
                if ((rate / stm32f4_pclk_div[i]) <= priv->max_clk_rate)
                        break;
        }
        if (i >= ARRAY_SIZE(stm32f4_pclk_div)) {
                dev_err(&pdev->dev, "adc clk selection failed\n");
                return -EINVAL;
        }

        priv->common.rate = rate / stm32f4_pclk_div[i];
        val = readl_relaxed(priv->common.base + STM32F4_ADC_CCR);
        val &= ~STM32F4_ADC_ADCPRE_MASK;
        val |= i << STM32F4_ADC_ADCPRE_SHIFT;
        writel_relaxed(val, priv->common.base + STM32F4_ADC_CCR);

        dev_dbg(&pdev->dev, "Using analog clock source at %ld kHz\n",
                priv->common.rate / 1000);

        return 0;
}

/**
 * struct stm32h7_adc_ck_spec - specification for stm32h7 adc clock
 * @ckmode: ADC clock mode, Async or sync with prescaler.
 * @presc: prescaler bitfield for async clock mode
 * @div: prescaler division ratio
 */
struct stm32h7_adc_ck_spec {
        u32 ckmode;
        u32 presc;
        int div;
};

static const struct stm32h7_adc_ck_spec stm32h7_adc_ckmodes_spec[] = {
        /* 00: CK_ADC[1..3]: Asynchronous clock modes */
        { 0, 0, 1 },
        { 0, 1, 2 },
        { 0, 2, 4 },
        { 0, 3, 6 },
        { 0, 4, 8 },
        { 0, 5, 10 },
        { 0, 6, 12 },
        { 0, 7, 16 },
        { 0, 8, 32 },
        { 0, 9, 64 },
        { 0, 10, 128 },
        { 0, 11, 256 },
        /* HCLK used: Synchronous clock modes (1, 2 or 4 prescaler) */
        { 1, 0, 1 },
        { 2, 0, 2 },
        { 3, 0, 4 },
};

static int stm32h7_adc_clk_sel(struct platform_device *pdev,
                               struct stm32_adc_priv *priv)
{
        u32 ckmode, presc, val;
        unsigned long rate;
        int i, div;

        /* stm32h7 bus clock is common for all ADC instances (mandatory) */
        if (!priv->bclk) {
                dev_err(&pdev->dev, "No 'bus' clock found\n");
                return -ENOENT;
        }

        /*
         * stm32h7 can use either 'bus' or 'adc' clock for analog circuitry.
         * So, choice is to have bus clock mandatory and adc clock optional.
         * If optional 'adc' clock has been found, then try to use it first.
         */
        if (priv->aclk) {
                /*
                 * Asynchronous clock modes (e.g. ckmode == 0)
                 * From spec: PLL output musn't exceed max rate
                 */
                rate = clk_get_rate(priv->aclk);
                if (!rate) {
                        dev_err(&pdev->dev, "Invalid adc clock rate: 0\n");
                        return -EINVAL;
                }

                for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
                        ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
                        presc = stm32h7_adc_ckmodes_spec[i].presc;
                        div = stm32h7_adc_ckmodes_spec[i].div;

                        if (ckmode)
                                continue;

                        if ((rate / div) <= priv->max_clk_rate)
                                goto out;
                }
        }

        /* Synchronous clock modes (e.g. ckmode is 1, 2 or 3) */
        rate = clk_get_rate(priv->bclk);
        if (!rate) {
                dev_err(&pdev->dev, "Invalid bus clock rate: 0\n");
                return -EINVAL;
        }

        for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
                ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
                presc = stm32h7_adc_ckmodes_spec[i].presc;
                div = stm32h7_adc_ckmodes_spec[i].div;

                if (!ckmode)
                        continue;

                if ((rate / div) <= priv->max_clk_rate)
                        goto out;
        }

        dev_err(&pdev->dev, "adc clk selection failed\n");
        return -EINVAL;

out:
        /* rate used later by each ADC instance to control BOOST mode */
        priv->common.rate = rate / div;

        /* Set common clock mode and prescaler */
        val = readl_relaxed(priv->common.base + STM32H7_ADC_CCR);
        val &= ~(STM32H7_CKMODE_MASK | STM32H7_PRESC_MASK);
        val |= ckmode << STM32H7_CKMODE_SHIFT;
        val |= presc << STM32H7_PRESC_SHIFT;
        writel_relaxed(val, priv->common.base + STM32H7_ADC_CCR);

        dev_dbg(&pdev->dev, "Using %s clock/%d source at %ld kHz\n",
                ckmode ? "bus" : "adc", div, priv->common.rate / 1000);

        return 0;
}

/* STM32F4 common registers definitions */
static const struct stm32_adc_common_regs stm32f4_adc_common_regs = {
        .csr = STM32F4_ADC_CSR,
        .ccr = STM32F4_ADC_CCR,
        .eoc1_msk = STM32F4_EOC1 | STM32F4_OVR1,
        .eoc2_msk = STM32F4_EOC2 | STM32F4_OVR2,
        .eoc3_msk = STM32F4_EOC3 | STM32F4_OVR3,
        .ier = STM32F4_ADC_CR1,
        .eocie_msk = STM32F4_EOCIE | STM32F4_OVRIE,
};

/* STM32H7 common registers definitions */
static const struct stm32_adc_common_regs stm32h7_adc_common_regs = {
        .csr = STM32H7_ADC_CSR,
        .ccr = STM32H7_ADC_CCR,
        .eoc1_msk = STM32H7_EOC_MST | STM32H7_OVR_MST,
        .eoc2_msk = STM32H7_EOC_SLV | STM32H7_OVR_SLV,
        .ier = STM32H7_ADC_IER,
        .eocie_msk = STM32H7_EOCIE | STM32H7_OVRIE,
};

static const unsigned int stm32_adc_offset[STM32_ADC_MAX_ADCS] = {
        0, STM32_ADC_OFFSET, STM32_ADC_OFFSET * 2,
};

static unsigned int stm32_adc_eoc_enabled(struct stm32_adc_priv *priv,
                                          unsigned int adc)
{
        u32 ier, offset = stm32_adc_offset[adc];

        ier = readl_relaxed(priv->common.base + offset + priv->cfg->regs->ier);

        return ier & priv->cfg->regs->eocie_msk;
}

/* ADC common interrupt for all instances */
static void stm32_adc_irq_handler(struct irq_desc *desc)
{
        struct stm32_adc_priv *priv = irq_desc_get_handler_data(desc);
        struct irq_chip *chip = irq_desc_get_chip(desc);
        u32 status;

        chained_irq_enter(chip, desc);
        status = readl_relaxed(priv->common.base + priv->cfg->regs->csr);

        /*
         * End of conversion may be handled by using IRQ or DMA. There may be a
         * race here when two conversions complete at the same time on several
         * ADCs. EOC may be read 'set' for several ADCs, with:
         * - an ADC configured to use DMA (EOC triggers the DMA request, and
         *   is then automatically cleared by DR read in hardware)
         * - an ADC configured to use IRQs (EOCIE bit is set. The handler must
         *   be called in this case)
         * So both EOC status bit in CSR and EOCIE control bit must be checked
         * before invoking the interrupt handler (e.g. call ISR only for
         * IRQ-enabled ADCs).
         */
        if (status & priv->cfg->regs->eoc1_msk &&
            stm32_adc_eoc_enabled(priv, 0))
                generic_handle_irq(irq_find_mapping(priv->domain, 0));

        if (status & priv->cfg->regs->eoc2_msk &&
            stm32_adc_eoc_enabled(priv, 1))
                generic_handle_irq(irq_find_mapping(priv->domain, 1));

        if (status & priv->cfg->regs->eoc3_msk &&
            stm32_adc_eoc_enabled(priv, 2))
                generic_handle_irq(irq_find_mapping(priv->domain, 2));

        chained_irq_exit(chip, desc);
};

static int stm32_adc_domain_map(struct irq_domain *d, unsigned int irq,
                                irq_hw_number_t hwirq)
{
        irq_set_chip_data(irq, d->host_data);
        irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_level_irq);

        return 0;
}

static void stm32_adc_domain_unmap(struct irq_domain *d, unsigned int irq)
{
        irq_set_chip_and_handler(irq, NULL, NULL);
        irq_set_chip_data(irq, NULL);
}

static const struct irq_domain_ops stm32_adc_domain_ops = {
        .map = stm32_adc_domain_map,
        .unmap  = stm32_adc_domain_unmap,
        .xlate = irq_domain_xlate_onecell,
};

static int stm32_adc_irq_probe(struct platform_device *pdev,
                               struct stm32_adc_priv *priv)
{
        struct device_node *np = pdev->dev.of_node;
        unsigned int i;

        for (i = 0; i < STM32_ADC_MAX_ADCS; i++) {
                priv->irq[i] = platform_get_irq(pdev, i);
                if (priv->irq[i] < 0) {
                        /*
                         * At least one interrupt must be provided, make others
                         * optional:
                         * - stm32f4/h7 shares a common interrupt.
                         * - stm32mp1, has one line per ADC (either for ADC1,
                         *   ADC2 or both).
                         */
                        if (i && priv->irq[i] == -ENXIO)
                                continue;

                        return priv->irq[i];
                }
        }

        priv->domain = irq_domain_add_simple(np, STM32_ADC_MAX_ADCS, 0,
                                             &stm32_adc_domain_ops,
                                             priv);
        if (!priv->domain) {
                dev_err(&pdev->dev, "Failed to add irq domain\n");
                return -ENOMEM;
        }

        for (i = 0; i < STM32_ADC_MAX_ADCS; i++) {
                if (priv->irq[i] < 0)
                        continue;
                irq_set_chained_handler(priv->irq[i], stm32_adc_irq_handler);
                irq_set_handler_data(priv->irq[i], priv);
        }

        return 0;
}

static void stm32_adc_irq_remove(struct platform_device *pdev,
                                 struct stm32_adc_priv *priv)
{
        int hwirq;
        unsigned int i;

        for (hwirq = 0; hwirq < STM32_ADC_MAX_ADCS; hwirq++)
                irq_dispose_mapping(irq_find_mapping(priv->domain, hwirq));
        irq_domain_remove(priv->domain);

        for (i = 0; i < STM32_ADC_MAX_ADCS; i++) {
                if (priv->irq[i] < 0)
                        continue;
                irq_set_chained_handler(priv->irq[i], NULL);
        }
}

static int stm32_adc_core_switches_supply_en(struct stm32_adc_priv *priv,
                                             struct device *dev)
{
        int ret;

        /*
         * On STM32H7 and STM32MP1, the ADC inputs are multiplexed with analog
         * switches (via PCSEL) which have reduced performances when their
         * supply is below 2.7V (vdda by default):
         * - Voltage booster can be used, to get full ADC performances
         *   (increases power consumption).
         * - Vdd can be used to supply them, if above 2.7V (STM32MP1 only).
         *
         * Recommended settings for ANASWVDD and EN_BOOSTER:
         * - vdda < 2.7V but vdd > 2.7V: ANASWVDD = 1, EN_BOOSTER = 0 (stm32mp1)
         * - vdda < 2.7V and vdd < 2.7V: ANASWVDD = 0, EN_BOOSTER = 1
         * - vdda >= 2.7V:               ANASWVDD = 0, EN_BOOSTER = 0 (default)
         */
        if (priv->vdda_uv < 2700000) {
                if (priv->syscfg && priv->vdd_uv > 2700000) {
                        ret = regulator_enable(priv->vdd);
                        if (ret < 0) {
                                dev_err(dev, "vdd enable failed %d\n", ret);
                                return ret;
                        }

                        ret = regmap_write(priv->syscfg,
                                           STM32MP1_SYSCFG_PMCSETR,
                                           STM32MP1_SYSCFG_ANASWVDD_MASK);
                        if (ret < 0) {
                                regulator_disable(priv->vdd);
                                dev_err(dev, "vdd select failed, %d\n", ret);
                                return ret;
                        }
                        dev_dbg(dev, "analog switches supplied by vdd\n");

                        return 0;
                }

                if (priv->booster) {
                        /*
                         * This is optional, as this is a trade-off between
                         * analog performance and power consumption.
                         */
                        ret = regulator_enable(priv->booster);
                        if (ret < 0) {
                                dev_err(dev, "booster enable failed %d\n", ret);
                                return ret;
                        }
                        dev_dbg(dev, "analog switches supplied by booster\n");

                        return 0;
                }
        }

        /* Fallback using vdda (default), nothing to do */
        dev_dbg(dev, "analog switches supplied by vdda (%d uV)\n",
                priv->vdda_uv);

        return 0;
}

static void stm32_adc_core_switches_supply_dis(struct stm32_adc_priv *priv)
{
        if (priv->vdda_uv < 2700000) {
                if (priv->syscfg && priv->vdd_uv > 2700000) {
                        regmap_write(priv->syscfg, STM32MP1_SYSCFG_PMCCLRR,
                                     STM32MP1_SYSCFG_ANASWVDD_MASK);
                        regulator_disable(priv->vdd);
                        return;
                }
                if (priv->booster)
                        regulator_disable(priv->booster);
        }
}

static int stm32_adc_core_hw_start(struct device *dev)
{
        struct stm32_adc_common *common = dev_get_drvdata(dev);
        struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
        int ret;

        ret = regulator_enable(priv->vdda);
        if (ret < 0) {
                dev_err(dev, "vdda enable failed %d\n", ret);
                return ret;
        }

        ret = regulator_get_voltage(priv->vdda);
        if (ret < 0) {
                dev_err(dev, "vdda get voltage failed, %d\n", ret);
                goto err_vdda_disable;
        }
        priv->vdda_uv = ret;

        ret = stm32_adc_core_switches_supply_en(priv, dev);
        if (ret < 0)
                goto err_vdda_disable;

        ret = regulator_enable(priv->vref);
        if (ret < 0) {
                dev_err(dev, "vref enable failed\n");
                goto err_switches_dis;
        }

        if (priv->bclk) {
                ret = clk_prepare_enable(priv->bclk);
                if (ret < 0) {
                        dev_err(dev, "bus clk enable failed\n");
                        goto err_regulator_disable;
                }
        }

        if (priv->aclk) {
                ret = clk_prepare_enable(priv->aclk);
                if (ret < 0) {
                        dev_err(dev, "adc clk enable failed\n");
                        goto err_bclk_disable;
                }
        }

        writel_relaxed(priv->ccr_bak, priv->common.base + priv->cfg->regs->ccr);

        return 0;

err_bclk_disable:
        if (priv->bclk)
                clk_disable_unprepare(priv->bclk);
err_regulator_disable:
        regulator_disable(priv->vref);
err_switches_dis:
        stm32_adc_core_switches_supply_dis(priv);
err_vdda_disable:
        regulator_disable(priv->vdda);

        return ret;
}

static void stm32_adc_core_hw_stop(struct device *dev)
{
        struct stm32_adc_common *common = dev_get_drvdata(dev);
        struct stm32_adc_priv *priv = to_stm32_adc_priv(common);

        /* Backup CCR that may be lost (depends on power state to achieve) */
        priv->ccr_bak = readl_relaxed(priv->common.base + priv->cfg->regs->ccr);
        if (priv->aclk)
                clk_disable_unprepare(priv->aclk);
        if (priv->bclk)
                clk_disable_unprepare(priv->bclk);
        regulator_disable(priv->vref);
        stm32_adc_core_switches_supply_dis(priv);
        regulator_disable(priv->vdda);
}

static int stm32_adc_core_switches_probe(struct device *dev,
                                         struct stm32_adc_priv *priv)
{
        struct device_node *np = dev->of_node;
        int ret;

        /* Analog switches supply can be controlled by syscfg (optional) */
        priv->syscfg = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
        if (IS_ERR(priv->syscfg)) {
                ret = PTR_ERR(priv->syscfg);
                if (ret != -ENODEV) {
                        if (ret != -EPROBE_DEFER)
                                dev_err(dev, "Can't probe syscfg: %d\n", ret);
                        return ret;
                }
                priv->syscfg = NULL;
        }

        /* Booster can be used to supply analog switches (optional) */
        if (priv->cfg->has_syscfg & HAS_VBOOSTER &&
            of_property_read_bool(np, "booster-supply")) {
                priv->booster = devm_regulator_get_optional(dev, "booster");
                if (IS_ERR(priv->booster)) {
                        ret = PTR_ERR(priv->booster);
                        if (ret != -ENODEV) {
                                if (ret != -EPROBE_DEFER)
                                        dev_err(dev, "can't get booster %d\n",
                                                ret);
                                return ret;
                        }
                        priv->booster = NULL;
                }
        }

        /* Vdd can be used to supply analog switches (optional) */
        if (priv->cfg->has_syscfg & HAS_ANASWVDD &&
            of_property_read_bool(np, "vdd-supply")) {
                priv->vdd = devm_regulator_get_optional(dev, "vdd");
                if (IS_ERR(priv->vdd)) {
                        ret = PTR_ERR(priv->vdd);
                        if (ret != -ENODEV) {
                                if (ret != -EPROBE_DEFER)
                                        dev_err(dev, "can't get vdd %d\n", ret);
                                return ret;
                        }
                        priv->vdd = NULL;
                }
        }

        if (priv->vdd) {
                ret = regulator_enable(priv->vdd);
                if (ret < 0) {
                        dev_err(dev, "vdd enable failed %d\n", ret);
                        return ret;
                }

                ret = regulator_get_voltage(priv->vdd);
                if (ret < 0) {
                        dev_err(dev, "vdd get voltage failed %d\n", ret);
                        regulator_disable(priv->vdd);
                        return ret;
                }
                priv->vdd_uv = ret;

                regulator_disable(priv->vdd);
        }

        return 0;
}

static int stm32_adc_probe(struct platform_device *pdev)
{
        struct stm32_adc_priv *priv;
        struct device *dev = &pdev->dev;
        struct device_node *np = pdev->dev.of_node;
        struct resource *res;
        u32 max_rate;
        int ret;

        if (!pdev->dev.of_node)
                return -ENODEV;

        priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
        if (!priv)
                return -ENOMEM;
        platform_set_drvdata(pdev, &priv->common);

        priv->cfg = (const struct stm32_adc_priv_cfg *)
                of_match_device(dev->driver->of_match_table, dev)->data;

        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        priv->common.base = devm_ioremap_resource(&pdev->dev, res);
        if (IS_ERR(priv->common.base))
                return PTR_ERR(priv->common.base);
        priv->common.phys_base = res->start;

        priv->vdda = devm_regulator_get(&pdev->dev, "vdda");
        if (IS_ERR(priv->vdda)) {
                ret = PTR_ERR(priv->vdda);
                if (ret != -EPROBE_DEFER)
                        dev_err(&pdev->dev, "vdda get failed, %d\n", ret);
                return ret;
        }

        priv->vref = devm_regulator_get(&pdev->dev, "vref");
        if (IS_ERR(priv->vref)) {
                ret = PTR_ERR(priv->vref);
                if (ret != -EPROBE_DEFER)
                        dev_err(&pdev->dev, "vref get failed, %d\n", ret);
                return ret;
        }

        priv->aclk = devm_clk_get(&pdev->dev, "adc");
        if (IS_ERR(priv->aclk)) {
                ret = PTR_ERR(priv->aclk);
                if (ret != -ENOENT) {
                        if (ret != -EPROBE_DEFER)
                                dev_err(&pdev->dev, "Can't get 'adc' clock\n");
                        return ret;
                }
                priv->aclk = NULL;
        }

        priv->bclk = devm_clk_get(&pdev->dev, "bus");
        if (IS_ERR(priv->bclk)) {
                ret = PTR_ERR(priv->bclk);
                if (ret != -ENOENT) {
                        if (ret != -EPROBE_DEFER)
                                dev_err(&pdev->dev, "Can't get 'bus' clock\n");
                        return ret;
                }
                priv->bclk = NULL;
        }

        ret = stm32_adc_core_switches_probe(dev, priv);
        if (ret)
                return ret;

        pm_runtime_get_noresume(dev);
        pm_runtime_set_active(dev);
        pm_runtime_set_autosuspend_delay(dev, STM32_ADC_CORE_SLEEP_DELAY_MS);
        pm_runtime_use_autosuspend(dev);
        pm_runtime_enable(dev);

        ret = stm32_adc_core_hw_start(dev);
        if (ret)
                goto err_pm_stop;

        ret = regulator_get_voltage(priv->vref);
        if (ret < 0) {
                dev_err(&pdev->dev, "vref get voltage failed, %d\n", ret);
                goto err_hw_stop;
        }
        priv->common.vref_mv = ret / 1000;
        dev_dbg(&pdev->dev, "vref+=%dmV\n", priv->common.vref_mv);

        ret = of_property_read_u32(pdev->dev.of_node, "st,max-clk-rate-hz",
                                   &max_rate);
        if (!ret)
                priv->max_clk_rate = min(max_rate, priv->cfg->max_clk_rate_hz);
        else
                priv->max_clk_rate = priv->cfg->max_clk_rate_hz;

        ret = priv->cfg->clk_sel(pdev, priv);
        if (ret < 0)
                goto err_hw_stop;

        ret = stm32_adc_irq_probe(pdev, priv);
        if (ret < 0)
                goto err_hw_stop;

        ret = of_platform_populate(np, NULL, NULL, &pdev->dev);
        if (ret < 0) {
                dev_err(&pdev->dev, "failed to populate DT children\n");
                goto err_irq_remove;
        }

        pm_runtime_mark_last_busy(dev);
        pm_runtime_put_autosuspend(dev);

        return 0;

err_irq_remove:
        stm32_adc_irq_remove(pdev, priv);
err_hw_stop:
        stm32_adc_core_hw_stop(dev);
err_pm_stop:
        pm_runtime_disable(dev);
        pm_runtime_set_suspended(dev);
        pm_runtime_put_noidle(dev);

        return ret;
}

static int stm32_adc_remove(struct platform_device *pdev)
{
        struct stm32_adc_common *common = platform_get_drvdata(pdev);
        struct stm32_adc_priv *priv = to_stm32_adc_priv(common);

        pm_runtime_get_sync(&pdev->dev);
        of_platform_depopulate(&pdev->dev);
        stm32_adc_irq_remove(pdev, priv);
        stm32_adc_core_hw_stop(&pdev->dev);
        pm_runtime_disable(&pdev->dev);
        pm_runtime_set_suspended(&pdev->dev);
        pm_runtime_put_noidle(&pdev->dev);

        return 0;
}

#if defined(CONFIG_PM)
static int stm32_adc_core_runtime_suspend(struct device *dev)
{
        stm32_adc_core_hw_stop(dev);

        return 0;
}

static int stm32_adc_core_runtime_resume(struct device *dev)
{
        return stm32_adc_core_hw_start(dev);
}
#endif

static const struct dev_pm_ops stm32_adc_core_pm_ops = {
        SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
                                pm_runtime_force_resume)
        SET_RUNTIME_PM_OPS(stm32_adc_core_runtime_suspend,
                           stm32_adc_core_runtime_resume,
                           NULL)
};

static const struct stm32_adc_priv_cfg stm32f4_adc_priv_cfg = {
        .regs = &stm32f4_adc_common_regs,
        .clk_sel = stm32f4_adc_clk_sel,
        .max_clk_rate_hz = 36000000,
};

static const struct stm32_adc_priv_cfg stm32h7_adc_priv_cfg = {
        .regs = &stm32h7_adc_common_regs,
        .clk_sel = stm32h7_adc_clk_sel,
        .max_clk_rate_hz = 36000000,
        .has_syscfg = HAS_VBOOSTER,
};

static const struct stm32_adc_priv_cfg stm32mp1_adc_priv_cfg = {
        .regs = &stm32h7_adc_common_regs,
        .clk_sel = stm32h7_adc_clk_sel,
        .max_clk_rate_hz = 40000000,
        .has_syscfg = HAS_VBOOSTER | HAS_ANASWVDD,
};

static const struct of_device_id stm32_adc_of_match[] = {
        {
                .compatible = "st,stm32f4-adc-core",
                .data = (void *)&stm32f4_adc_priv_cfg
        }, {
                .compatible = "st,stm32h7-adc-core",
                .data = (void *)&stm32h7_adc_priv_cfg
        }, {
                .compatible = "st,stm32mp1-adc-core",
                .data = (void *)&stm32mp1_adc_priv_cfg
        }, {
        },
};
MODULE_DEVICE_TABLE(of, stm32_adc_of_match);

static struct platform_driver stm32_adc_driver = {
        .probe = stm32_adc_probe,
        .remove = stm32_adc_remove,
        .driver = {
                .name = "stm32-adc-core",
                .of_match_table = stm32_adc_of_match,
                .pm = &stm32_adc_core_pm_ops,
        },
};
module_platform_driver(stm32_adc_driver);

MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
MODULE_DESCRIPTION("STMicroelectronics STM32 ADC core driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:stm32-adc-core");