[PATCH v3 0/3] add imx93 adc support

[PATCH v3 0/3] add imx93 adc support

[haibo.chen]

From: Haibo Chen <haibo.chen@nxp.com>

V3:
  For dt-bings, add some change according to review comments, and pass dt_binding_check.
  For dts, add #io-channel-cells = <1>; to pass dtbs_check
  For ADC driver, no change.

V2:
  For ADC driver, add change according to matainer's commets.

Haibo Chen (3):
  iio: adc: add imx93 adc support
  dt-bindings: iio: adc: Add binding documentation for NXP IMX93 ADC
  arm64: dts: imx93: add ADC support

 .../bindings/iio/adc/nxp,imx93-adc.yaml       |  81 +++
 MAINTAINERS                                   |   4 +-
 .../boot/dts/freescale/imx93-11x11-evk.dts    |  12 +
 arch/arm64/boot/dts/freescale/imx93.dtsi      |  13 +
 drivers/iio/adc/Kconfig                       |  10 +
 drivers/iio/adc/Makefile                      |   1 +
 drivers/iio/adc/imx93_adc.c                   | 474 ++++++++++++++++++
 7 files changed, 594 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/devicetree/bindings/iio/adc/nxp,imx93-adc.yaml
 create mode 100644 drivers/iio/adc/imx93_adc.c

-- 
2.34.1

[PATCH v3 1/3] iio: adc: add imx93 adc support

[haibo.chen]

From: Haibo Chen <haibo.chen@nxp.com>

The ADC in i.mx93 is a total new ADC IP, add a driver to support
this ADC.

Currently, only support one shot normal conversion triggered by
software. For other mode, will add in future.

Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
---
 MAINTAINERS                 |   4 +-
 drivers/iio/adc/Kconfig     |  10 +
 drivers/iio/adc/Makefile    |   1 +
 drivers/iio/adc/imx93_adc.c | 474 ++++++++++++++++++++++++++++++++++++
 4 files changed, 488 insertions(+), 1 deletion(-)
 create mode 100644 drivers/iio/adc/imx93_adc.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 30e032abd196..37431a02cd60 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15020,14 +15020,16 @@ S:	Maintained
 F:	Documentation/devicetree/bindings/iio/adc/nxp,imx8qxp-adc.yaml
 F:	drivers/iio/adc/imx8qxp-adc.c
 
-NXP i.MX 7D/6SX/6UL AND VF610 ADC DRIVER
+NXP i.MX 7D/6SX/6UL/93 AND VF610 ADC DRIVER
 M:	Haibo Chen <haibo.chen@nxp.com>
 L:	linux-iio@vger.kernel.org
 L:	linux-imx@nxp.com
 S:	Maintained
 F:	Documentation/devicetree/bindings/iio/adc/fsl,imx7d-adc.yaml
 F:	Documentation/devicetree/bindings/iio/adc/fsl,vf610-adc.yaml
+F:	Documentation/devicetree/bindings/iio/adc/nxp,imx93-adc.yaml
 F:	drivers/iio/adc/imx7d_adc.c
+F:	drivers/iio/adc/imx93_adc.c
 F:	drivers/iio/adc/vf610_adc.c
 
 NXP PF8100/PF8121A/PF8200 PMIC REGULATOR DEVICE DRIVER
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 46c4fc2fc534..4fc826f52b8c 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -565,6 +565,16 @@ config IMX8QXP_ADC
 	  This driver can also be built as a module. If so, the module will be
 	  called imx8qxp-adc.
 
+config IMX93_ADC
+	tristate "IMX93 ADC driver"
+	depends on ARCH_MXC || COMPILE_TEST
+	depends on HAS_IOMEM
+	help
+	  Say yes here to build support for IMX93 ADC.
+
+	  This driver can also be built as a module. If so, the module will be
+	  called imx93_adc.
+
 config LP8788_ADC
 	tristate "LP8788 ADC driver"
 	depends on MFD_LP8788
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 6e08415c3f3a..df8c0f26307d 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -49,6 +49,7 @@ obj-$(CONFIG_HI8435) += hi8435.o
 obj-$(CONFIG_HX711) += hx711.o
 obj-$(CONFIG_IMX7D_ADC) += imx7d_adc.o
 obj-$(CONFIG_IMX8QXP_ADC) += imx8qxp-adc.o
+obj-$(CONFIG_IMX93_ADC) += imx93_adc.o
 obj-$(CONFIG_INA2XX_ADC) += ina2xx-adc.o
 obj-$(CONFIG_INGENIC_ADC) += ingenic-adc.o
 obj-$(CONFIG_INTEL_MRFLD_ADC) += intel_mrfld_adc.o
diff --git a/drivers/iio/adc/imx93_adc.c b/drivers/iio/adc/imx93_adc.c
new file mode 100644
index 000000000000..3ea16a70e746
--- /dev/null
+++ b/drivers/iio/adc/imx93_adc.c
@@ -0,0 +1,474 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * NXP i.MX93 ADC driver
+ *
+ * Copyright 2022 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_IDLE			0
+#define IMX93_ADC_POWER_DOWN		1
+#define IMX93_ADC_WAIT_STATE		2
+#define IMX93_ADC_BUSY_IN_CALIBRATION	3
+#define IMX93_ADC_SAMPLE		4
+#define IMX93_ADC_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_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 1 min!\n");
+		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");
+		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;
+	long ret;
+	u32 vref_uv;
+
+	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 IIO_VAL_INT;
+		else
+			return ret;
+
+	case IIO_CHAN_INFO_SCALE:
+		ret = vref_uv = regulator_get_voltage(adc->vref);
+		if (ret < 0)
+			return ret;
+		*val = vref_uv / 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) {
+		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);
+
+	/* 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) {
+		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 = IMX93_ADC_DRIVER_NAME;
+	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(&pdev->dev, "Could not prepare or enable the 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(dev, "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(dev, "Couldn't register the device.\n");
+		goto error_free_adc_irq;
+	}
+
+	pm_runtime_set_active(dev);
+	pm_runtime_set_autosuspend_delay(dev, 50);
+	pm_runtime_use_autosuspend(dev);
+	pm_runtime_enable(dev);
+
+	return 0;
+
+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);
+	imx93_adc_power_down(adc);
+
+	pm_runtime_disable(dev);
+	pm_runtime_put_noidle(dev);
+	iio_device_unregister(indio_dev);
+	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");
-- 
2.34.1

Re: [PATCH v3 1/3] iio: adc: add imx93 adc support

[Jonathan Cameron]

On Mon, 19 Dec 2022 18:13:34 +0800
haibo.chen@nxp.com wrote:

> From: Haibo Chen <haibo.chen@nxp.com>
> 
> The ADC in i.mx93 is a total new ADC IP, add a driver to support
> this ADC.
> 
> Currently, only support one shot normal conversion triggered by
> software. For other mode, will add in future.
> 
> Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
Hi Haibo,

A few minor things inline. Otherwise looks good to me.

Thanks,

Jonathan

> ---
> diff --git a/drivers/iio/adc/imx93_adc.c b/drivers/iio/adc/imx93_adc.c
> new file mode 100644
> index 000000000000..3ea16a70e746
> --- /dev/null
> +++ b/drivers/iio/adc/imx93_adc.c
> @@ -0,0 +1,474 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * NXP i.MX93 ADC driver
> + *
> + * Copyright 2022 NXP
> + */
> +

...

> +/* 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 */
Are these field values? If so I'd like the naming to indicate
which field and which register etc. It might end up a bit
long, but it makes it clear the value is matched with
where we are getting it from.

> +#define IMX93_ADC_IDLE			0
> +#define IMX93_ADC_POWER_DOWN		1
> +#define IMX93_ADC_WAIT_STATE		2
> +#define IMX93_ADC_BUSY_IN_CALIBRATION	3
> +#define IMX93_ADC_SAMPLE		4
> +#define IMX93_ADC_CONVERSION		6
> +
> +#define IMX93_ADC_TIMEOUT		msecs_to_jiffies(100)


> +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;
> +	long ret;
> +	u32 vref_uv;
> +
> +	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 IIO_VAL_INT;
> +		else
> +			return ret;
Prefer the error out of line. Makes for slightly easier reviewing as it
is the more common pattern.

		if (ret < 0)
			return ret;

		return IIO_VAL_INT;

> +
> +	case IIO_CHAN_INFO_SCALE:
> +		ret = vref_uv = regulator_get_voltage(adc->vref);
> +		if (ret < 0)
> +			return ret;
> +		*val = vref_uv / 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 int imx93_adc_probe(struct platform_device *pdev)
> +{

> +
> +	platform_set_drvdata(pdev, indio_dev);
> +
> +	init_completion(&adc->completion);
> +
> +	indio_dev->name = IMX93_ADC_DRIVER_NAME;
I'd rather see the string here than use a define. There is no strong
reason that this should be the driver name - so I don' want to have
to go look at the define to check it contains "imx93" which I'd expect
to see here.

> +
> +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);
> +	imx93_adc_power_down(adc);
> +
> +	pm_runtime_disable(dev);
> +	pm_runtime_put_noidle(dev);
> +	iio_device_unregister(indio_dev);

You don't remove the userspace interfaces until this iio_device_unregister()
call.  Having turned the power off before this point is probably not a good idea.
you should be fine moving the imx93_adc_power_down() after this point.
Hopefully that should reflect any equivalent handling order in probe()
(I haven't checked!)


> +	free_irq(adc->irq, adc);
> +	clk_disable_unprepare(adc->ipg_clk);
> +	regulator_disable(adc->vref);
> +
> +	return 0;
> +}
> +

[PATCH v3 2/3] dt-bindings: iio: adc: Add binding documentation for NXP IMX93 ADC

[haibo.chen]

From: Haibo Chen <haibo.chen@nxp.com>

The IMX93 SoC has a new ADC IP, so add binding documentation
for NXP IMX93 ADC.

Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
---
 .../bindings/iio/adc/nxp,imx93-adc.yaml       | 81 +++++++++++++++++++
 1 file changed, 81 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/adc/nxp,imx93-adc.yaml

diff --git a/Documentation/devicetree/bindings/iio/adc/nxp,imx93-adc.yaml b/Documentation/devicetree/bindings/iio/adc/nxp,imx93-adc.yaml
new file mode 100644
index 000000000000..dacc526dc695
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/nxp,imx93-adc.yaml
@@ -0,0 +1,81 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/adc/nxp,imx93-adc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NXP iMX93 ADC
+
+maintainers:
+  - Haibo Chen <haibo.chen@nxp.com>
+
+description:
+  The ADC on iMX93 is a 8-channel 12-bit 1MS/s ADC with 4 channels
+  connected to pins. it support normal and inject mode, include
+  One-Shot and Scan (continuous) conversions. Programmable DMA
+  enables for each channel  Also this ADC contain alternate analog
+  watchdog thresholds, select threshold through input ports. And
+  also has Self-test logic and Software-initiated calibration.
+
+properties:
+  compatible:
+    const: nxp,imx93-adc
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    items:
+      - description: WDGnL, watchdog threshold interrupt requests.
+      - description: WDGnH, watchdog threshold interrupt requests.
+      - description: normal conversion, include EOC (End of Conversion),
+          ECH (End of Chain), JEOC (End of Injected Conversion) and
+          JECH (End of injected Chain).
+      - description: Self-testing Interrupts.
+
+  clocks:
+    maxItems: 1
+
+  clock-names:
+    const: ipg
+
+  vref-supply:
+    description:
+      The reference voltage which used to establish channel scaling.
+
+  "#io-channel-cells":
+    const: 1
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+  - clock-names
+  - vref-supply
+  - "#io-channel-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+    #include <dt-bindings/clock/imx93-clock.h>
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    soc {
+        #address-cells = <1>;
+        #size-cells = <1>;
+        adc@44530000 {
+            compatible = "nxp,imx93-adc";
+            reg = <0x44530000 0x10000>;
+            interrupts = <GIC_SPI 217 IRQ_TYPE_LEVEL_HIGH>,
+                         <GIC_SPI 218 IRQ_TYPE_LEVEL_HIGH>,
+                         <GIC_SPI 219 IRQ_TYPE_LEVEL_HIGH>,
+                         <GIC_SPI 268 IRQ_TYPE_LEVEL_HIGH>;
+            clocks = <&clk IMX93_CLK_ADC1_GATE>;
+            clock-names = "ipg";
+            vref-supply = <&reg_vref_1v8>;
+            #io-channel-cells = <1>;
+        };
+    };
+...
-- 
2.34.1

Re: [PATCH v3 2/3] dt-bindings: iio: adc: Add binding documentation for NXP IMX93 ADC

[Rob Herring]

On Mon, Dec 19, 2022 at 06:13:35PM +0800, haibo.chen@nxp.com wrote:
> From: Haibo Chen <haibo.chen@nxp.com>

For the subject, no need to say 'binding documentation' twice:

dt-bindings: iio: adc: Add NXP IMX93 ADC

> 
> The IMX93 SoC has a new ADC IP, so add binding documentation
> for NXP IMX93 ADC.
> 
> Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
> ---
>  .../bindings/iio/adc/nxp,imx93-adc.yaml       | 81 +++++++++++++++++++
>  1 file changed, 81 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/iio/adc/nxp,imx93-adc.yaml

With that,

Reviewed-by: Rob Herring <robh@kernel.org>

[PATCH v3 3/3] arm64: dts: imx93: add ADC support

[haibo.chen]

From: Haibo Chen <haibo.chen@nxp.com>

Add ADC support for imx93-11x11-evk board.

Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
---
 arch/arm64/boot/dts/freescale/imx93-11x11-evk.dts | 12 ++++++++++++
 arch/arm64/boot/dts/freescale/imx93.dtsi          | 13 +++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/arch/arm64/boot/dts/freescale/imx93-11x11-evk.dts b/arch/arm64/boot/dts/freescale/imx93-11x11-evk.dts
index 69786c326db0..cab5f4d66bf9 100644
--- a/arch/arm64/boot/dts/freescale/imx93-11x11-evk.dts
+++ b/arch/arm64/boot/dts/freescale/imx93-11x11-evk.dts
@@ -15,6 +15,13 @@ chosen {
 		stdout-path = &lpuart1;
 	};
 
+	reg_vref_1v8: regulator-adc-vref {
+		compatible = "regulator-fixed";
+		regulator-name = "vref_1v8";
+		regulator-min-microvolt = <1800000>;
+		regulator-max-microvolt = <1800000>;
+	};
+
 	reg_usdhc2_vmmc: regulator-usdhc2 {
 		compatible = "regulator-fixed";
 		pinctrl-names = "default";
@@ -27,6 +34,11 @@ reg_usdhc2_vmmc: regulator-usdhc2 {
 	};
 };
 
+&adc1 {
+	vref-supply = <&reg_vref_1v8>;
+	status = "okay";
+};
+
 &mu1 {
 	status = "okay";
 };
diff --git a/arch/arm64/boot/dts/freescale/imx93.dtsi b/arch/arm64/boot/dts/freescale/imx93.dtsi
index 5d79663b3b84..a0d39dd34591 100644
--- a/arch/arm64/boot/dts/freescale/imx93.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx93.dtsi
@@ -266,6 +266,19 @@ anatop: anatop@44480000 {
 				compatible = "fsl,imx93-anatop", "syscon";
 				reg = <0x44480000 0x10000>;
 			};
+
+			adc1: adc@44530000 {
+				compatible = "nxp,imx93-adc";
+				reg = <0x44530000 0x10000>;
+				interrupts = <GIC_SPI 217 IRQ_TYPE_LEVEL_HIGH>,
+					     <GIC_SPI 218 IRQ_TYPE_LEVEL_HIGH>,
+					     <GIC_SPI 219 IRQ_TYPE_LEVEL_HIGH>,
+					     <GIC_SPI 268 IRQ_TYPE_LEVEL_HIGH>;
+				clocks = <&clk IMX93_CLK_ADC1_GATE>;
+				clock-names = "ipg";
+				#io-channel-cells = <1>;
+				status = "disabled";
+			};
 		};
 
 		aips2: bus@42000000 {
-- 
2.34.1