| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * NXP i.MX8QXP ADC driver |
| * |
| * Based on the work of Haibo Chen <haibo.chen@nxp.com> |
| * The initial developer of the original code is Haibo Chen. |
| * Portions created by Haibo Chen are Copyright (C) 2018 NXP. |
| * All Rights Reserved. |
| * |
| * Copyright (C) 2018 NXP |
| * Copyright (C) 2021 Cai Huoqing |
| */ |
| #include <linux/bitfield.h> |
| #include <linux/bits.h> |
| #include <linux/clk.h> |
| #include <linux/completion.h> |
| #include <linux/delay.h> |
| #include <linux/err.h> |
| #include <linux/interrupt.h> |
| #include <linux/io.h> |
| #include <linux/kernel.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> |
| |
| #include <linux/iio/iio.h> |
| |
| #define ADC_DRIVER_NAME "imx8qxp-adc" |
| |
| /* Register map definition */ |
| #define IMX8QXP_ADR_ADC_CTRL 0x10 |
| #define IMX8QXP_ADR_ADC_STAT 0x14 |
| #define IMX8QXP_ADR_ADC_IE 0x18 |
| #define IMX8QXP_ADR_ADC_DE 0x1c |
| #define IMX8QXP_ADR_ADC_CFG 0x20 |
| #define IMX8QXP_ADR_ADC_FCTRL 0x30 |
| #define IMX8QXP_ADR_ADC_SWTRIG 0x34 |
| #define IMX8QXP_ADR_ADC_TCTRL(tid) (0xc0 + (tid) * 4) |
| #define IMX8QXP_ADR_ADC_CMDH(cid) (0x100 + (cid) * 8) |
| #define IMX8QXP_ADR_ADC_CMDL(cid) (0x104 + (cid) * 8) |
| #define IMX8QXP_ADR_ADC_RESFIFO 0x300 |
| #define IMX8QXP_ADR_ADC_TST 0xffc |
| |
| /* ADC bit shift */ |
| #define IMX8QXP_ADC_IE_FWMIE_MASK GENMASK(1, 0) |
| #define IMX8QXP_ADC_CTRL_FIFO_RESET_MASK BIT(8) |
| #define IMX8QXP_ADC_CTRL_SOFTWARE_RESET_MASK BIT(1) |
| #define IMX8QXP_ADC_CTRL_ADC_EN_MASK BIT(0) |
| #define IMX8QXP_ADC_TCTRL_TCMD_MASK GENMASK(31, 24) |
| #define IMX8QXP_ADC_TCTRL_TDLY_MASK GENMASK(23, 16) |
| #define IMX8QXP_ADC_TCTRL_TPRI_MASK GENMASK(15, 8) |
| #define IMX8QXP_ADC_TCTRL_HTEN_MASK GENMASK(7, 0) |
| #define IMX8QXP_ADC_CMDL_CSCALE_MASK GENMASK(13, 8) |
| #define IMX8QXP_ADC_CMDL_MODE_MASK BIT(7) |
| #define IMX8QXP_ADC_CMDL_DIFF_MASK BIT(6) |
| #define IMX8QXP_ADC_CMDL_ABSEL_MASK BIT(5) |
| #define IMX8QXP_ADC_CMDL_ADCH_MASK GENMASK(2, 0) |
| #define IMX8QXP_ADC_CMDH_NEXT_MASK GENMASK(31, 24) |
| #define IMX8QXP_ADC_CMDH_LOOP_MASK GENMASK(23, 16) |
| #define IMX8QXP_ADC_CMDH_AVGS_MASK GENMASK(15, 12) |
| #define IMX8QXP_ADC_CMDH_STS_MASK BIT(8) |
| #define IMX8QXP_ADC_CMDH_LWI_MASK GENMASK(7, 7) |
| #define IMX8QXP_ADC_CMDH_CMPEN_MASK GENMASK(0, 0) |
| #define IMX8QXP_ADC_CFG_PWREN_MASK BIT(28) |
| #define IMX8QXP_ADC_CFG_PUDLY_MASK GENMASK(23, 16) |
| #define IMX8QXP_ADC_CFG_REFSEL_MASK GENMASK(7, 6) |
| #define IMX8QXP_ADC_CFG_PWRSEL_MASK GENMASK(5, 4) |
| #define IMX8QXP_ADC_CFG_TPRICTRL_MASK GENMASK(3, 0) |
| #define IMX8QXP_ADC_FCTRL_FWMARK_MASK GENMASK(20, 16) |
| #define IMX8QXP_ADC_FCTRL_FCOUNT_MASK GENMASK(4, 0) |
| #define IMX8QXP_ADC_RESFIFO_VAL_MASK GENMASK(18, 3) |
| |
| /* ADC PARAMETER*/ |
| #define IMX8QXP_ADC_CMDL_CHANNEL_SCALE_FULL GENMASK(5, 0) |
| #define IMX8QXP_ADC_CMDL_SEL_A_A_B_CHANNEL 0 |
| #define IMX8QXP_ADC_CMDL_STANDARD_RESOLUTION 0 |
| #define IMX8QXP_ADC_CMDL_MODE_SINGLE 0 |
| #define IMX8QXP_ADC_CMDH_LWI_INCREMENT_DIS 0 |
| #define IMX8QXP_ADC_CMDH_CMPEN_DIS 0 |
| #define IMX8QXP_ADC_PAUSE_EN BIT(31) |
| #define IMX8QXP_ADC_TCTRL_TPRI_PRIORITY_HIGH 0 |
| |
| #define IMX8QXP_ADC_TCTRL_HTEN_HW_TIRG_DIS 0 |
| |
| #define IMX8QXP_ADC_TIMEOUT msecs_to_jiffies(100) |
| |
| #define IMX8QXP_ADC_MAX_FIFO_SIZE 16 |
| |
| struct imx8qxp_adc { |
| struct device *dev; |
| void __iomem *regs; |
| struct clk *clk; |
| struct clk *ipg_clk; |
| struct regulator *vref; |
| /* Serialise ADC channel reads */ |
| struct mutex lock; |
| struct completion completion; |
| u32 fifo[IMX8QXP_ADC_MAX_FIFO_SIZE]; |
| }; |
| |
| #define IMX8QXP_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 imx8qxp_adc_iio_channels[] = { |
| IMX8QXP_ADC_CHAN(0), |
| IMX8QXP_ADC_CHAN(1), |
| IMX8QXP_ADC_CHAN(2), |
| IMX8QXP_ADC_CHAN(3), |
| IMX8QXP_ADC_CHAN(4), |
| IMX8QXP_ADC_CHAN(5), |
| IMX8QXP_ADC_CHAN(6), |
| IMX8QXP_ADC_CHAN(7), |
| }; |
| |
| static void imx8qxp_adc_reset(struct imx8qxp_adc *adc) |
| { |
| u32 ctrl; |
| |
| /*software reset, need to clear the set bit*/ |
| ctrl = readl(adc->regs + IMX8QXP_ADR_ADC_CTRL); |
| ctrl |= FIELD_PREP(IMX8QXP_ADC_CTRL_SOFTWARE_RESET_MASK, 1); |
| writel(ctrl, adc->regs + IMX8QXP_ADR_ADC_CTRL); |
| udelay(10); |
| ctrl &= ~FIELD_PREP(IMX8QXP_ADC_CTRL_SOFTWARE_RESET_MASK, 1); |
| writel(ctrl, adc->regs + IMX8QXP_ADR_ADC_CTRL); |
| |
| /* reset the fifo */ |
| ctrl |= FIELD_PREP(IMX8QXP_ADC_CTRL_FIFO_RESET_MASK, 1); |
| writel(ctrl, adc->regs + IMX8QXP_ADR_ADC_CTRL); |
| } |
| |
| static void imx8qxp_adc_reg_config(struct imx8qxp_adc *adc, int channel) |
| { |
| u32 adc_cfg, adc_tctrl, adc_cmdl, adc_cmdh; |
| |
| /* ADC configuration */ |
| adc_cfg = FIELD_PREP(IMX8QXP_ADC_CFG_PWREN_MASK, 1) | |
| FIELD_PREP(IMX8QXP_ADC_CFG_PUDLY_MASK, 0x80)| |
| FIELD_PREP(IMX8QXP_ADC_CFG_REFSEL_MASK, 0) | |
| FIELD_PREP(IMX8QXP_ADC_CFG_PWRSEL_MASK, 3) | |
| FIELD_PREP(IMX8QXP_ADC_CFG_TPRICTRL_MASK, 0); |
| writel(adc_cfg, adc->regs + IMX8QXP_ADR_ADC_CFG); |
| |
| /* config the trigger control */ |
| adc_tctrl = FIELD_PREP(IMX8QXP_ADC_TCTRL_TCMD_MASK, 1) | |
| FIELD_PREP(IMX8QXP_ADC_TCTRL_TDLY_MASK, 0) | |
| FIELD_PREP(IMX8QXP_ADC_TCTRL_TPRI_MASK, IMX8QXP_ADC_TCTRL_TPRI_PRIORITY_HIGH) | |
| FIELD_PREP(IMX8QXP_ADC_TCTRL_HTEN_MASK, IMX8QXP_ADC_TCTRL_HTEN_HW_TIRG_DIS); |
| writel(adc_tctrl, adc->regs + IMX8QXP_ADR_ADC_TCTRL(0)); |
| |
| /* config the cmd */ |
| adc_cmdl = FIELD_PREP(IMX8QXP_ADC_CMDL_CSCALE_MASK, IMX8QXP_ADC_CMDL_CHANNEL_SCALE_FULL) | |
| FIELD_PREP(IMX8QXP_ADC_CMDL_MODE_MASK, IMX8QXP_ADC_CMDL_STANDARD_RESOLUTION) | |
| FIELD_PREP(IMX8QXP_ADC_CMDL_DIFF_MASK, IMX8QXP_ADC_CMDL_MODE_SINGLE) | |
| FIELD_PREP(IMX8QXP_ADC_CMDL_ABSEL_MASK, IMX8QXP_ADC_CMDL_SEL_A_A_B_CHANNEL) | |
| FIELD_PREP(IMX8QXP_ADC_CMDL_ADCH_MASK, channel); |
| writel(adc_cmdl, adc->regs + IMX8QXP_ADR_ADC_CMDL(0)); |
| |
| adc_cmdh = FIELD_PREP(IMX8QXP_ADC_CMDH_NEXT_MASK, 0) | |
| FIELD_PREP(IMX8QXP_ADC_CMDH_LOOP_MASK, 0) | |
| FIELD_PREP(IMX8QXP_ADC_CMDH_AVGS_MASK, 7) | |
| FIELD_PREP(IMX8QXP_ADC_CMDH_STS_MASK, 0) | |
| FIELD_PREP(IMX8QXP_ADC_CMDH_LWI_MASK, IMX8QXP_ADC_CMDH_LWI_INCREMENT_DIS) | |
| FIELD_PREP(IMX8QXP_ADC_CMDH_CMPEN_MASK, IMX8QXP_ADC_CMDH_CMPEN_DIS); |
| writel(adc_cmdh, adc->regs + IMX8QXP_ADR_ADC_CMDH(0)); |
| } |
| |
| static void imx8qxp_adc_fifo_config(struct imx8qxp_adc *adc) |
| { |
| u32 fifo_ctrl, interrupt_en; |
| |
| fifo_ctrl = readl(adc->regs + IMX8QXP_ADR_ADC_FCTRL); |
| fifo_ctrl &= ~IMX8QXP_ADC_FCTRL_FWMARK_MASK; |
| /* set the watermark level to 1 */ |
| fifo_ctrl |= FIELD_PREP(IMX8QXP_ADC_FCTRL_FWMARK_MASK, 0); |
| writel(fifo_ctrl, adc->regs + IMX8QXP_ADR_ADC_FCTRL); |
| |
| /* FIFO Watermark Interrupt Enable */ |
| interrupt_en = readl(adc->regs + IMX8QXP_ADR_ADC_IE); |
| interrupt_en |= FIELD_PREP(IMX8QXP_ADC_IE_FWMIE_MASK, 1); |
| writel(interrupt_en, adc->regs + IMX8QXP_ADR_ADC_IE); |
| } |
| |
| static void imx8qxp_adc_disable(struct imx8qxp_adc *adc) |
| { |
| u32 ctrl; |
| |
| ctrl = readl(adc->regs + IMX8QXP_ADR_ADC_CTRL); |
| ctrl &= ~FIELD_PREP(IMX8QXP_ADC_CTRL_ADC_EN_MASK, 1); |
| writel(ctrl, adc->regs + IMX8QXP_ADR_ADC_CTRL); |
| } |
| |
| static int imx8qxp_adc_read_raw(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *chan, |
| int *val, int *val2, long mask) |
| { |
| struct imx8qxp_adc *adc = iio_priv(indio_dev); |
| struct device *dev = adc->dev; |
| |
| u32 ctrl; |
| long ret; |
| |
| switch (mask) { |
| case IIO_CHAN_INFO_RAW: |
| pm_runtime_get_sync(dev); |
| |
| mutex_lock(&adc->lock); |
| reinit_completion(&adc->completion); |
| |
| imx8qxp_adc_reg_config(adc, chan->channel); |
| |
| imx8qxp_adc_fifo_config(adc); |
| |
| /* adc enable */ |
| ctrl = readl(adc->regs + IMX8QXP_ADR_ADC_CTRL); |
| ctrl |= FIELD_PREP(IMX8QXP_ADC_CTRL_ADC_EN_MASK, 1); |
| writel(ctrl, adc->regs + IMX8QXP_ADR_ADC_CTRL); |
| /* adc start */ |
| writel(1, adc->regs + IMX8QXP_ADR_ADC_SWTRIG); |
| |
| ret = wait_for_completion_interruptible_timeout(&adc->completion, |
| IMX8QXP_ADC_TIMEOUT); |
| |
| pm_runtime_mark_last_busy(dev); |
| pm_runtime_put_sync_autosuspend(dev); |
| |
| if (ret == 0) { |
| mutex_unlock(&adc->lock); |
| return -ETIMEDOUT; |
| } |
| if (ret < 0) { |
| mutex_unlock(&adc->lock); |
| return ret; |
| } |
| |
| *val = adc->fifo[0]; |
| |
| mutex_unlock(&adc->lock); |
| 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->clk) / 3; |
| return IIO_VAL_INT; |
| |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| static irqreturn_t imx8qxp_adc_isr(int irq, void *dev_id) |
| { |
| struct imx8qxp_adc *adc = dev_id; |
| u32 fifo_count; |
| int i; |
| |
| fifo_count = FIELD_GET(IMX8QXP_ADC_FCTRL_FCOUNT_MASK, |
| readl(adc->regs + IMX8QXP_ADR_ADC_FCTRL)); |
| |
| for (i = 0; i < fifo_count; i++) |
| adc->fifo[i] = FIELD_GET(IMX8QXP_ADC_RESFIFO_VAL_MASK, |
| readl_relaxed(adc->regs + IMX8QXP_ADR_ADC_RESFIFO)); |
| |
| if (fifo_count) |
| complete(&adc->completion); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static int imx8qxp_adc_reg_access(struct iio_dev *indio_dev, unsigned int reg, |
| unsigned int writeval, unsigned int *readval) |
| { |
| struct imx8qxp_adc *adc = iio_priv(indio_dev); |
| struct device *dev = adc->dev; |
| |
| if (!readval || reg % 4 || reg > IMX8QXP_ADR_ADC_TST) |
| return -EINVAL; |
| |
| pm_runtime_get_sync(dev); |
| |
| *readval = readl(adc->regs + reg); |
| |
| pm_runtime_mark_last_busy(dev); |
| pm_runtime_put_sync_autosuspend(dev); |
| |
| return 0; |
| } |
| |
| static const struct iio_info imx8qxp_adc_iio_info = { |
| .read_raw = &imx8qxp_adc_read_raw, |
| .debugfs_reg_access = &imx8qxp_adc_reg_access, |
| }; |
| |
| static int imx8qxp_adc_probe(struct platform_device *pdev) |
| { |
| struct imx8qxp_adc *adc; |
| struct iio_dev *indio_dev; |
| struct device *dev = &pdev->dev; |
| int irq; |
| int ret; |
| |
| indio_dev = devm_iio_device_alloc(dev, sizeof(*adc)); |
| if (!indio_dev) { |
| dev_err(dev, "Failed allocating iio device\n"); |
| return -ENOMEM; |
| } |
| |
| 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 PTR_ERR(adc->regs); |
| |
| irq = platform_get_irq(pdev, 0); |
| if (irq < 0) |
| return irq; |
| |
| adc->clk = devm_clk_get(dev, "per"); |
| if (IS_ERR(adc->clk)) |
| return dev_err_probe(dev, PTR_ERR(adc->clk), "Failed getting clock\n"); |
| |
| 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) { |
| dev_err(dev, "Can't enable adc reference top voltage\n"); |
| return ret; |
| } |
| |
| platform_set_drvdata(pdev, indio_dev); |
| |
| init_completion(&adc->completion); |
| |
| indio_dev->name = ADC_DRIVER_NAME; |
| indio_dev->info = &imx8qxp_adc_iio_info; |
| indio_dev->modes = INDIO_DIRECT_MODE; |
| indio_dev->channels = imx8qxp_adc_iio_channels; |
| indio_dev->num_channels = ARRAY_SIZE(imx8qxp_adc_iio_channels); |
| |
| ret = clk_prepare_enable(adc->clk); |
| if (ret) { |
| dev_err(&pdev->dev, "Could not prepare or enable the clock.\n"); |
| goto error_regulator_disable; |
| } |
| |
| ret = clk_prepare_enable(adc->ipg_clk); |
| if (ret) { |
| dev_err(&pdev->dev, "Could not prepare or enable the clock.\n"); |
| goto error_adc_clk_disable; |
| } |
| |
| ret = devm_request_irq(dev, irq, imx8qxp_adc_isr, 0, ADC_DRIVER_NAME, adc); |
| if (ret < 0) { |
| dev_err(dev, "Failed requesting irq, irq = %d\n", irq); |
| goto error_ipg_clk_disable; |
| } |
| |
| imx8qxp_adc_reset(adc); |
| |
| ret = iio_device_register(indio_dev); |
| if (ret) { |
| imx8qxp_adc_disable(adc); |
| dev_err(dev, "Couldn't register the device.\n"); |
| goto error_ipg_clk_disable; |
| } |
| |
| pm_runtime_set_active(dev); |
| pm_runtime_set_autosuspend_delay(dev, 50); |
| pm_runtime_use_autosuspend(dev); |
| pm_runtime_enable(dev); |
| |
| return 0; |
| |
| error_ipg_clk_disable: |
| clk_disable_unprepare(adc->ipg_clk); |
| error_adc_clk_disable: |
| clk_disable_unprepare(adc->clk); |
| error_regulator_disable: |
| regulator_disable(adc->vref); |
| |
| return ret; |
| } |
| |
| static int imx8qxp_adc_remove(struct platform_device *pdev) |
| { |
| struct iio_dev *indio_dev = platform_get_drvdata(pdev); |
| struct imx8qxp_adc *adc = iio_priv(indio_dev); |
| struct device *dev = adc->dev; |
| |
| pm_runtime_get_sync(dev); |
| |
| iio_device_unregister(indio_dev); |
| |
| imx8qxp_adc_disable(adc); |
| |
| clk_disable_unprepare(adc->clk); |
| clk_disable_unprepare(adc->ipg_clk); |
| regulator_disable(adc->vref); |
| |
| pm_runtime_disable(dev); |
| pm_runtime_put_noidle(dev); |
| |
| return 0; |
| } |
| |
| static int imx8qxp_adc_runtime_suspend(struct device *dev) |
| { |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| struct imx8qxp_adc *adc = iio_priv(indio_dev); |
| |
| imx8qxp_adc_disable(adc); |
| |
| clk_disable_unprepare(adc->clk); |
| clk_disable_unprepare(adc->ipg_clk); |
| regulator_disable(adc->vref); |
| |
| return 0; |
| } |
| |
| static int imx8qxp_adc_runtime_resume(struct device *dev) |
| { |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| struct imx8qxp_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->clk); |
| if (ret) { |
| dev_err(dev, "Could not prepare or enable clock.\n"); |
| goto err_disable_reg; |
| } |
| |
| ret = clk_prepare_enable(adc->ipg_clk); |
| if (ret) { |
| dev_err(dev, "Could not prepare or enable clock.\n"); |
| goto err_unprepare_clk; |
| } |
| |
| imx8qxp_adc_reset(adc); |
| |
| return 0; |
| |
| err_unprepare_clk: |
| clk_disable_unprepare(adc->clk); |
| |
| err_disable_reg: |
| regulator_disable(adc->vref); |
| |
| return ret; |
| } |
| |
| static DEFINE_RUNTIME_DEV_PM_OPS(imx8qxp_adc_pm_ops, |
| imx8qxp_adc_runtime_suspend, |
| imx8qxp_adc_runtime_resume, NULL); |
| |
| static const struct of_device_id imx8qxp_adc_match[] = { |
| { .compatible = "nxp,imx8qxp-adc", }, |
| { /* sentinel */ } |
| }; |
| MODULE_DEVICE_TABLE(of, imx8qxp_adc_match); |
| |
| static struct platform_driver imx8qxp_adc_driver = { |
| .probe = imx8qxp_adc_probe, |
| .remove = imx8qxp_adc_remove, |
| .driver = { |
| .name = ADC_DRIVER_NAME, |
| .of_match_table = imx8qxp_adc_match, |
| .pm = pm_ptr(&imx8qxp_adc_pm_ops), |
| }, |
| }; |
| |
| module_platform_driver(imx8qxp_adc_driver); |
| |
| MODULE_DESCRIPTION("i.MX8QuadXPlus ADC driver"); |
| MODULE_LICENSE("GPL v2"); |