diff options
Diffstat (limited to 'drivers/iio/adc/imx8qxp-adc.c')
| -rw-r--r-- | drivers/iio/adc/imx8qxp-adc.c | 494 |
1 files changed, 494 insertions, 0 deletions
diff --git a/drivers/iio/adc/imx8qxp-adc.c b/drivers/iio/adc/imx8qxp-adc.c new file mode 100644 index 000000000000..901dd8e1b32f --- /dev/null +++ b/drivers/iio/adc/imx8qxp-adc.c @@ -0,0 +1,494 @@ +// 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/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) + +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; +}; + +#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, vref_uv; + 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 = FIELD_GET(IMX8QXP_ADC_RESFIFO_VAL_MASK, + readl(adc->regs + IMX8QXP_ADR_ADC_RESFIFO)); + + mutex_unlock(&adc->lock); + return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: + vref_uv = regulator_get_voltage(adc->vref); + *val = vref_uv / 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; + + fifo_count = FIELD_GET(IMX8QXP_ADC_FCTRL_FCOUNT_MASK, + readl(adc->regs + IMX8QXP_ADR_ADC_FCTRL)); + + 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 __maybe_unused 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 __maybe_unused 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 const struct dev_pm_ops imx8qxp_adc_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume) + SET_RUNTIME_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 = &imx8qxp_adc_pm_ops, + }, +}; + +module_platform_driver(imx8qxp_adc_driver); + +MODULE_DESCRIPTION("i.MX8QuadXPlus ADC driver"); +MODULE_LICENSE("GPL v2"); |