--- /dev/null
+// 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 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 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");
projects / platform / kernel / linux-rpi.git / commitdiff