| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * NXP i.MX93 ADC driver |
| * |
| * Copyright 2023 NXP |
| */ |
| |
| #include <linux/bitfield.h> |
| #include <linux/clk.h> |
| #include <linux/completion.h> |
| #include <linux/err.h> |
| #include <linux/iio/iio.h> |
| #include <linux/interrupt.h> |
| #include <linux/io.h> |
| #include <linux/iopoll.h> |
| #include <linux/mod_devicetable.h> |
| #include <linux/module.h> |
| #include <linux/platform_device.h> |
| #include <linux/pm_runtime.h> |
| #include <linux/regulator/consumer.h> |
| |
| #define IMX93_ADC_DRIVER_NAME "imx93-adc" |
| |
| /* Register map definition */ |
| #define IMX93_ADC_MCR 0x00 |
| #define IMX93_ADC_MSR 0x04 |
| #define IMX93_ADC_ISR 0x10 |
| #define IMX93_ADC_IMR 0x20 |
| #define IMX93_ADC_CIMR0 0x24 |
| #define IMX93_ADC_CTR0 0x94 |
| #define IMX93_ADC_NCMR0 0xA4 |
| #define IMX93_ADC_PCDR0 0x100 |
| #define IMX93_ADC_PCDR1 0x104 |
| #define IMX93_ADC_PCDR2 0x108 |
| #define IMX93_ADC_PCDR3 0x10c |
| #define IMX93_ADC_PCDR4 0x110 |
| #define IMX93_ADC_PCDR5 0x114 |
| #define IMX93_ADC_PCDR6 0x118 |
| #define IMX93_ADC_PCDR7 0x11c |
| #define IMX93_ADC_CALSTAT 0x39C |
| |
| /* ADC bit shift */ |
| #define IMX93_ADC_MCR_MODE_MASK BIT(29) |
| #define IMX93_ADC_MCR_NSTART_MASK BIT(24) |
| #define IMX93_ADC_MCR_CALSTART_MASK BIT(14) |
| #define IMX93_ADC_MCR_ADCLKSE_MASK BIT(8) |
| #define IMX93_ADC_MCR_PWDN_MASK BIT(0) |
| #define IMX93_ADC_MSR_CALFAIL_MASK BIT(30) |
| #define IMX93_ADC_MSR_CALBUSY_MASK BIT(29) |
| #define IMX93_ADC_MSR_ADCSTATUS_MASK GENMASK(2, 0) |
| #define IMX93_ADC_ISR_ECH_MASK BIT(0) |
| #define IMX93_ADC_ISR_EOC_MASK BIT(1) |
| #define IMX93_ADC_ISR_EOC_ECH_MASK (IMX93_ADC_ISR_EOC_MASK | \ |
| IMX93_ADC_ISR_ECH_MASK) |
| #define IMX93_ADC_IMR_JEOC_MASK BIT(3) |
| #define IMX93_ADC_IMR_JECH_MASK BIT(2) |
| #define IMX93_ADC_IMR_EOC_MASK BIT(1) |
| #define IMX93_ADC_IMR_ECH_MASK BIT(0) |
| #define IMX93_ADC_PCDR_CDATA_MASK GENMASK(11, 0) |
| |
| /* ADC status */ |
| #define IMX93_ADC_MSR_ADCSTATUS_IDLE 0 |
| #define IMX93_ADC_MSR_ADCSTATUS_POWER_DOWN 1 |
| #define IMX93_ADC_MSR_ADCSTATUS_WAIT_STATE 2 |
| #define IMX93_ADC_MSR_ADCSTATUS_BUSY_IN_CALIBRATION 3 |
| #define IMX93_ADC_MSR_ADCSTATUS_SAMPLE 4 |
| #define IMX93_ADC_MSR_ADCSTATUS_CONVERSION 6 |
| |
| #define IMX93_ADC_TIMEOUT msecs_to_jiffies(100) |
| |
| struct imx93_adc { |
| struct device *dev; |
| void __iomem *regs; |
| struct clk *ipg_clk; |
| int irq; |
| struct regulator *vref; |
| /* lock to protect against multiple access to the device */ |
| struct mutex lock; |
| struct completion completion; |
| }; |
| |
| #define IMX93_ADC_CHAN(_idx) { \ |
| .type = IIO_VOLTAGE, \ |
| .indexed = 1, \ |
| .channel = (_idx), \ |
| .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ |
| .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ |
| BIT(IIO_CHAN_INFO_SAMP_FREQ), \ |
| } |
| |
| static const struct iio_chan_spec imx93_adc_iio_channels[] = { |
| IMX93_ADC_CHAN(0), |
| IMX93_ADC_CHAN(1), |
| IMX93_ADC_CHAN(2), |
| IMX93_ADC_CHAN(3), |
| }; |
| |
| static void imx93_adc_power_down(struct imx93_adc *adc) |
| { |
| u32 mcr, msr; |
| int ret; |
| |
| mcr = readl(adc->regs + IMX93_ADC_MCR); |
| mcr |= FIELD_PREP(IMX93_ADC_MCR_PWDN_MASK, 1); |
| writel(mcr, adc->regs + IMX93_ADC_MCR); |
| |
| ret = readl_poll_timeout(adc->regs + IMX93_ADC_MSR, msr, |
| ((msr & IMX93_ADC_MSR_ADCSTATUS_MASK) == |
| IMX93_ADC_MSR_ADCSTATUS_POWER_DOWN), |
| 1, 50); |
| if (ret == -ETIMEDOUT) |
| dev_warn(adc->dev, |
| "ADC do not in power down mode, current MSR is %x\n", |
| msr); |
| } |
| |
| static void imx93_adc_power_up(struct imx93_adc *adc) |
| { |
| u32 mcr; |
| |
| /* bring ADC out of power down state, in idle state */ |
| mcr = readl(adc->regs + IMX93_ADC_MCR); |
| mcr &= ~FIELD_PREP(IMX93_ADC_MCR_PWDN_MASK, 1); |
| writel(mcr, adc->regs + IMX93_ADC_MCR); |
| } |
| |
| static void imx93_adc_config_ad_clk(struct imx93_adc *adc) |
| { |
| u32 mcr; |
| |
| /* put adc in power down mode */ |
| imx93_adc_power_down(adc); |
| |
| /* config the AD_CLK equal to bus clock */ |
| mcr = readl(adc->regs + IMX93_ADC_MCR); |
| mcr |= FIELD_PREP(IMX93_ADC_MCR_ADCLKSE_MASK, 1); |
| writel(mcr, adc->regs + IMX93_ADC_MCR); |
| |
| imx93_adc_power_up(adc); |
| } |
| |
| static int imx93_adc_calibration(struct imx93_adc *adc) |
| { |
| u32 mcr, msr; |
| int ret; |
| |
| /* make sure ADC in power down mode */ |
| imx93_adc_power_down(adc); |
| |
| /* config SAR controller operating clock */ |
| mcr = readl(adc->regs + IMX93_ADC_MCR); |
| mcr &= ~FIELD_PREP(IMX93_ADC_MCR_ADCLKSE_MASK, 1); |
| writel(mcr, adc->regs + IMX93_ADC_MCR); |
| |
| imx93_adc_power_up(adc); |
| |
| /* |
| * TODO: we use the default TSAMP/NRSMPL/AVGEN in MCR, |
| * can add the setting of these bit if need in future. |
| */ |
| |
| /* run calibration */ |
| mcr = readl(adc->regs + IMX93_ADC_MCR); |
| mcr |= FIELD_PREP(IMX93_ADC_MCR_CALSTART_MASK, 1); |
| writel(mcr, adc->regs + IMX93_ADC_MCR); |
| |
| /* wait calibration to be finished */ |
| ret = readl_poll_timeout(adc->regs + IMX93_ADC_MSR, msr, |
| !(msr & IMX93_ADC_MSR_CALBUSY_MASK), 1000, 2000000); |
| if (ret == -ETIMEDOUT) { |
| dev_warn(adc->dev, "ADC do not finish calibration in 2 min!\n"); |
| imx93_adc_power_down(adc); |
| return ret; |
| } |
| |
| /* check whether calbration is success or not */ |
| msr = readl(adc->regs + IMX93_ADC_MSR); |
| if (msr & IMX93_ADC_MSR_CALFAIL_MASK) { |
| dev_warn(adc->dev, "ADC calibration failed!\n"); |
| imx93_adc_power_down(adc); |
| return -EAGAIN; |
| } |
| |
| return 0; |
| } |
| |
| static int imx93_adc_read_channel_conversion(struct imx93_adc *adc, |
| int channel_number, |
| int *result) |
| { |
| u32 channel; |
| u32 imr, mcr, pcda; |
| long ret; |
| |
| reinit_completion(&adc->completion); |
| |
| /* config channel mask register */ |
| channel = 1 << channel_number; |
| writel(channel, adc->regs + IMX93_ADC_NCMR0); |
| |
| /* TODO: can config desired sample time in CTRn if need */ |
| |
| /* config interrupt mask */ |
| imr = FIELD_PREP(IMX93_ADC_IMR_EOC_MASK, 1); |
| writel(imr, adc->regs + IMX93_ADC_IMR); |
| writel(channel, adc->regs + IMX93_ADC_CIMR0); |
| |
| /* config one-shot mode */ |
| mcr = readl(adc->regs + IMX93_ADC_MCR); |
| mcr &= ~FIELD_PREP(IMX93_ADC_MCR_MODE_MASK, 1); |
| writel(mcr, adc->regs + IMX93_ADC_MCR); |
| |
| /* start normal conversion */ |
| mcr = readl(adc->regs + IMX93_ADC_MCR); |
| mcr |= FIELD_PREP(IMX93_ADC_MCR_NSTART_MASK, 1); |
| writel(mcr, adc->regs + IMX93_ADC_MCR); |
| |
| ret = wait_for_completion_interruptible_timeout(&adc->completion, |
| IMX93_ADC_TIMEOUT); |
| if (ret == 0) |
| return -ETIMEDOUT; |
| |
| if (ret < 0) |
| return ret; |
| |
| pcda = readl(adc->regs + IMX93_ADC_PCDR0 + channel_number * 4); |
| |
| *result = FIELD_GET(IMX93_ADC_PCDR_CDATA_MASK, pcda); |
| |
| return ret; |
| } |
| |
| static int imx93_adc_read_raw(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *chan, |
| int *val, int *val2, long mask) |
| { |
| struct imx93_adc *adc = iio_priv(indio_dev); |
| struct device *dev = adc->dev; |
| int ret; |
| |
| switch (mask) { |
| case IIO_CHAN_INFO_RAW: |
| pm_runtime_get_sync(dev); |
| mutex_lock(&adc->lock); |
| ret = imx93_adc_read_channel_conversion(adc, chan->channel, val); |
| mutex_unlock(&adc->lock); |
| pm_runtime_mark_last_busy(dev); |
| pm_runtime_put_sync_autosuspend(dev); |
| if (ret < 0) |
| return ret; |
| |
| return IIO_VAL_INT; |
| |
| case IIO_CHAN_INFO_SCALE: |
| ret = regulator_get_voltage(adc->vref); |
| if (ret < 0) |
| return ret; |
| *val = ret / 1000; |
| *val2 = 12; |
| return IIO_VAL_FRACTIONAL_LOG2; |
| |
| case IIO_CHAN_INFO_SAMP_FREQ: |
| *val = clk_get_rate(adc->ipg_clk); |
| return IIO_VAL_INT; |
| |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| static irqreturn_t imx93_adc_isr(int irq, void *dev_id) |
| { |
| struct imx93_adc *adc = dev_id; |
| u32 isr, eoc, unexpected; |
| |
| isr = readl(adc->regs + IMX93_ADC_ISR); |
| |
| if (FIELD_GET(IMX93_ADC_ISR_EOC_ECH_MASK, isr)) { |
| eoc = isr & IMX93_ADC_ISR_EOC_ECH_MASK; |
| writel(eoc, adc->regs + IMX93_ADC_ISR); |
| complete(&adc->completion); |
| } |
| |
| unexpected = isr & ~IMX93_ADC_ISR_EOC_ECH_MASK; |
| if (unexpected) { |
| writel(unexpected, adc->regs + IMX93_ADC_ISR); |
| dev_err(adc->dev, "Unexpected interrupt 0x%08x.\n", unexpected); |
| return IRQ_NONE; |
| } |
| |
| return IRQ_HANDLED; |
| } |
| |
| static const struct iio_info imx93_adc_iio_info = { |
| .read_raw = &imx93_adc_read_raw, |
| }; |
| |
| static int imx93_adc_probe(struct platform_device *pdev) |
| { |
| struct imx93_adc *adc; |
| struct iio_dev *indio_dev; |
| struct device *dev = &pdev->dev; |
| int ret; |
| |
| indio_dev = devm_iio_device_alloc(dev, sizeof(*adc)); |
| if (!indio_dev) |
| return dev_err_probe(dev, -ENOMEM, |
| "Failed allocating iio device\n"); |
| |
| adc = iio_priv(indio_dev); |
| adc->dev = dev; |
| |
| mutex_init(&adc->lock); |
| adc->regs = devm_platform_ioremap_resource(pdev, 0); |
| if (IS_ERR(adc->regs)) |
| return dev_err_probe(dev, PTR_ERR(adc->regs), |
| "Failed getting ioremap resource\n"); |
| |
| /* The third irq is for ADC conversion usage */ |
| adc->irq = platform_get_irq(pdev, 2); |
| if (adc->irq < 0) |
| return adc->irq; |
| |
| adc->ipg_clk = devm_clk_get(dev, "ipg"); |
| if (IS_ERR(adc->ipg_clk)) |
| return dev_err_probe(dev, PTR_ERR(adc->ipg_clk), |
| "Failed getting clock.\n"); |
| |
| adc->vref = devm_regulator_get(dev, "vref"); |
| if (IS_ERR(adc->vref)) |
| return dev_err_probe(dev, PTR_ERR(adc->vref), |
| "Failed getting reference voltage.\n"); |
| |
| ret = regulator_enable(adc->vref); |
| if (ret) |
| return dev_err_probe(dev, ret, |
| "Failed to enable reference voltage.\n"); |
| |
| platform_set_drvdata(pdev, indio_dev); |
| |
| init_completion(&adc->completion); |
| |
| indio_dev->name = "imx93-adc"; |
| indio_dev->info = &imx93_adc_iio_info; |
| indio_dev->modes = INDIO_DIRECT_MODE; |
| indio_dev->channels = imx93_adc_iio_channels; |
| indio_dev->num_channels = ARRAY_SIZE(imx93_adc_iio_channels); |
| |
| ret = clk_prepare_enable(adc->ipg_clk); |
| if (ret) { |
| dev_err_probe(dev, ret, |
| "Failed to enable ipg clock.\n"); |
| goto error_regulator_disable; |
| } |
| |
| ret = request_irq(adc->irq, imx93_adc_isr, 0, IMX93_ADC_DRIVER_NAME, adc); |
| if (ret < 0) { |
| dev_err_probe(dev, ret, |
| "Failed requesting irq, irq = %d\n", adc->irq); |
| goto error_ipg_clk_disable; |
| } |
| |
| ret = imx93_adc_calibration(adc); |
| if (ret < 0) |
| goto error_free_adc_irq; |
| |
| imx93_adc_config_ad_clk(adc); |
| |
| ret = iio_device_register(indio_dev); |
| if (ret) { |
| dev_err_probe(dev, ret, |
| "Failed to register this iio device.\n"); |
| goto error_adc_power_down; |
| } |
| |
| pm_runtime_set_active(dev); |
| pm_runtime_set_autosuspend_delay(dev, 50); |
| pm_runtime_use_autosuspend(dev); |
| pm_runtime_enable(dev); |
| |
| return 0; |
| |
| error_adc_power_down: |
| imx93_adc_power_down(adc); |
| error_free_adc_irq: |
| free_irq(adc->irq, adc); |
| error_ipg_clk_disable: |
| clk_disable_unprepare(adc->ipg_clk); |
| error_regulator_disable: |
| regulator_disable(adc->vref); |
| |
| return ret; |
| } |
| |
| static int imx93_adc_remove(struct platform_device *pdev) |
| { |
| struct iio_dev *indio_dev = platform_get_drvdata(pdev); |
| struct imx93_adc *adc = iio_priv(indio_dev); |
| struct device *dev = adc->dev; |
| |
| /* adc power down need clock on */ |
| pm_runtime_get_sync(dev); |
| |
| pm_runtime_disable(dev); |
| pm_runtime_dont_use_autosuspend(dev); |
| pm_runtime_put_noidle(dev); |
| |
| iio_device_unregister(indio_dev); |
| imx93_adc_power_down(adc); |
| free_irq(adc->irq, adc); |
| clk_disable_unprepare(adc->ipg_clk); |
| regulator_disable(adc->vref); |
| |
| return 0; |
| } |
| |
| static int imx93_adc_runtime_suspend(struct device *dev) |
| { |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| struct imx93_adc *adc = iio_priv(indio_dev); |
| |
| imx93_adc_power_down(adc); |
| clk_disable_unprepare(adc->ipg_clk); |
| regulator_disable(adc->vref); |
| |
| return 0; |
| } |
| |
| static int imx93_adc_runtime_resume(struct device *dev) |
| { |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| struct imx93_adc *adc = iio_priv(indio_dev); |
| int ret; |
| |
| ret = regulator_enable(adc->vref); |
| if (ret) { |
| dev_err(dev, |
| "Can't enable adc reference top voltage, err = %d\n", |
| ret); |
| return ret; |
| } |
| |
| ret = clk_prepare_enable(adc->ipg_clk); |
| if (ret) { |
| dev_err(dev, "Could not prepare or enable clock.\n"); |
| goto err_disable_reg; |
| } |
| |
| imx93_adc_power_up(adc); |
| |
| return 0; |
| |
| err_disable_reg: |
| regulator_disable(adc->vref); |
| |
| return ret; |
| } |
| |
| static DEFINE_RUNTIME_DEV_PM_OPS(imx93_adc_pm_ops, |
| imx93_adc_runtime_suspend, |
| imx93_adc_runtime_resume, NULL); |
| |
| static const struct of_device_id imx93_adc_match[] = { |
| { .compatible = "nxp,imx93-adc", }, |
| { /* sentinel */ } |
| }; |
| MODULE_DEVICE_TABLE(of, imx93_adc_match); |
| |
| static struct platform_driver imx93_adc_driver = { |
| .probe = imx93_adc_probe, |
| .remove = imx93_adc_remove, |
| .driver = { |
| .name = IMX93_ADC_DRIVER_NAME, |
| .of_match_table = imx93_adc_match, |
| .pm = pm_ptr(&imx93_adc_pm_ops), |
| }, |
| }; |
| |
| module_platform_driver(imx93_adc_driver); |
| |
| MODULE_DESCRIPTION("NXP i.MX93 ADC driver"); |
| MODULE_AUTHOR("Haibo Chen <haibo.chen@nxp.com>"); |
| MODULE_LICENSE("GPL"); |