iio: adc: add IMX7D ADC driver support
authorHaibo Chen <haibo.chen@freescale.com>
Tue, 8 Dec 2015 10:26:20 +0000 (18:26 +0800)
committerJonathan Cameron <jic23@kernel.org>
Sat, 12 Dec 2015 16:25:41 +0000 (16:25 +0000)
Freescale i.MX7D soc contains a new ADC IP. This patch add this ADC
driver support, and the driver only support ADC software trigger.

Signed-off-by: Haibo Chen <haibo.chen@freescale.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
drivers/iio/adc/Kconfig
drivers/iio/adc/Makefile
drivers/iio/adc/imx7d_adc.c [new file with mode: 0644]

index cb68bd9..605ff42 100644 (file)
@@ -204,6 +204,15 @@ config INA2XX_ADC
          Say yes here to build support for TI INA2xx family of Power Monitors.
          This driver is mutually exclusive with the HWMON version.
 
+config IMX7D_ADC
+       tristate "IMX7D ADC driver"
+       depends on ARCH_MXC || COMPILE_TEST
+       help
+         Say yes here to build support for IMX7D ADC.
+
+         This driver can also be built as a module. If so, the module will be
+         called imx7d_adc.
+
 config LP8788_ADC
        tristate "LP8788 ADC driver"
        depends on MFD_LP8788
index c62c5fa..6435780 100644 (file)
@@ -20,6 +20,7 @@ obj-$(CONFIG_CC10001_ADC) += cc10001_adc.o
 obj-$(CONFIG_DA9150_GPADC) += da9150-gpadc.o
 obj-$(CONFIG_EXYNOS_ADC) += exynos_adc.o
 obj-$(CONFIG_HI8435) += hi8435.o
+obj-$(CONFIG_IMX7D_ADC) += imx7d_adc.o
 obj-$(CONFIG_INA2XX_ADC) += ina2xx-adc.o
 obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o
 obj-$(CONFIG_MAX1027) += max1027.o
diff --git a/drivers/iio/adc/imx7d_adc.c b/drivers/iio/adc/imx7d_adc.c
new file mode 100644 (file)
index 0000000..e2241ee
--- /dev/null
@@ -0,0 +1,609 @@
+/*
+ * Freescale i.MX7D ADC driver
+ *
+ * Copyright (C) 2015 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/clk.h>
+#include <linux/completion.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/regulator/consumer.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/driver.h>
+#include <linux/iio/sysfs.h>
+
+/* ADC register */
+#define IMX7D_REG_ADC_CH_A_CFG1                        0x00
+#define IMX7D_REG_ADC_CH_A_CFG2                        0x10
+#define IMX7D_REG_ADC_CH_B_CFG1                        0x20
+#define IMX7D_REG_ADC_CH_B_CFG2                        0x30
+#define IMX7D_REG_ADC_CH_C_CFG1                        0x40
+#define IMX7D_REG_ADC_CH_C_CFG2                        0x50
+#define IMX7D_REG_ADC_CH_D_CFG1                        0x60
+#define IMX7D_REG_ADC_CH_D_CFG2                        0x70
+#define IMX7D_REG_ADC_CH_SW_CFG                        0x80
+#define IMX7D_REG_ADC_TIMER_UNIT               0x90
+#define IMX7D_REG_ADC_DMA_FIFO                 0xa0
+#define IMX7D_REG_ADC_FIFO_STATUS              0xb0
+#define IMX7D_REG_ADC_INT_SIG_EN               0xc0
+#define IMX7D_REG_ADC_INT_EN                   0xd0
+#define IMX7D_REG_ADC_INT_STATUS               0xe0
+#define IMX7D_REG_ADC_CHA_B_CNV_RSLT           0xf0
+#define IMX7D_REG_ADC_CHC_D_CNV_RSLT           0x100
+#define IMX7D_REG_ADC_CH_SW_CNV_RSLT           0x110
+#define IMX7D_REG_ADC_DMA_FIFO_DAT             0x120
+#define IMX7D_REG_ADC_ADC_CFG                  0x130
+
+#define IMX7D_REG_ADC_CHANNEL_CFG2_BASE                0x10
+#define IMX7D_EACH_CHANNEL_REG_OFFSET          0x20
+
+#define IMX7D_REG_ADC_CH_CFG1_CHANNEL_EN                       (0x1 << 31)
+#define IMX7D_REG_ADC_CH_CFG1_CHANNEL_SINGLE                   BIT(30)
+#define IMX7D_REG_ADC_CH_CFG1_CHANNEL_AVG_EN                   BIT(29)
+#define IMX7D_REG_ADC_CH_CFG1_CHANNEL_SEL(x)                   ((x) << 24)
+
+#define IMX7D_REG_ADC_CH_CFG2_AVG_NUM_4                                (0x0 << 12)
+#define IMX7D_REG_ADC_CH_CFG2_AVG_NUM_8                                (0x1 << 12)
+#define IMX7D_REG_ADC_CH_CFG2_AVG_NUM_16                       (0x2 << 12)
+#define IMX7D_REG_ADC_CH_CFG2_AVG_NUM_32                       (0x3 << 12)
+
+#define IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_4                     (0x0 << 29)
+#define IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_8                     (0x1 << 29)
+#define IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_16                    (0x2 << 29)
+#define IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_32                    (0x3 << 29)
+#define IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_64                    (0x4 << 29)
+#define IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_128                   (0x5 << 29)
+
+#define IMX7D_REG_ADC_ADC_CFG_ADC_CLK_DOWN                     BIT(31)
+#define IMX7D_REG_ADC_ADC_CFG_ADC_POWER_DOWN                   BIT(1)
+#define IMX7D_REG_ADC_ADC_CFG_ADC_EN                           BIT(0)
+
+#define IMX7D_REG_ADC_INT_CHA_COV_INT_EN                       BIT(8)
+#define IMX7D_REG_ADC_INT_CHB_COV_INT_EN                       BIT(9)
+#define IMX7D_REG_ADC_INT_CHC_COV_INT_EN                       BIT(10)
+#define IMX7D_REG_ADC_INT_CHD_COV_INT_EN                       BIT(11)
+#define IMX7D_REG_ADC_INT_CHANNEL_INT_EN \
+       (IMX7D_REG_ADC_INT_CHA_COV_INT_EN | \
+        IMX7D_REG_ADC_INT_CHB_COV_INT_EN | \
+        IMX7D_REG_ADC_INT_CHC_COV_INT_EN | \
+        IMX7D_REG_ADC_INT_CHD_COV_INT_EN)
+#define IMX7D_REG_ADC_INT_STATUS_CHANNEL_INT_STATUS            0xf00
+#define IMX7D_REG_ADC_INT_STATUS_CHANNEL_CONV_TIME_OUT         0xf0000
+
+#define IMX7D_ADC_TIMEOUT              msecs_to_jiffies(100)
+
+enum imx7d_adc_clk_pre_div {
+       IMX7D_ADC_ANALOG_CLK_PRE_DIV_4,
+       IMX7D_ADC_ANALOG_CLK_PRE_DIV_8,
+       IMX7D_ADC_ANALOG_CLK_PRE_DIV_16,
+       IMX7D_ADC_ANALOG_CLK_PRE_DIV_32,
+       IMX7D_ADC_ANALOG_CLK_PRE_DIV_64,
+       IMX7D_ADC_ANALOG_CLK_PRE_DIV_128,
+};
+
+enum imx7d_adc_average_num {
+       IMX7D_ADC_AVERAGE_NUM_4,
+       IMX7D_ADC_AVERAGE_NUM_8,
+       IMX7D_ADC_AVERAGE_NUM_16,
+       IMX7D_ADC_AVERAGE_NUM_32,
+};
+
+struct imx7d_adc_feature {
+       enum imx7d_adc_clk_pre_div clk_pre_div;
+       enum imx7d_adc_average_num avg_num;
+
+       u32 core_time_unit;     /* impact the sample rate */
+
+       bool average_en;
+};
+
+struct imx7d_adc {
+       struct device *dev;
+       void __iomem *regs;
+       struct clk *clk;
+
+       u32 vref_uv;
+       u32 value;
+       u32 channel;
+       u32 pre_div_num;
+
+       struct regulator *vref;
+       struct imx7d_adc_feature adc_feature;
+
+       struct completion completion;
+};
+
+struct imx7d_adc_analogue_core_clk {
+       u32 pre_div;
+       u32 reg_config;
+};
+
+#define IMX7D_ADC_ANALOGUE_CLK_CONFIG(_pre_div, _reg_conf) {   \
+       .pre_div = (_pre_div),                                  \
+       .reg_config = (_reg_conf),                              \
+}
+
+static const struct imx7d_adc_analogue_core_clk imx7d_adc_analogue_clk[] = {
+       IMX7D_ADC_ANALOGUE_CLK_CONFIG(4, IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_4),
+       IMX7D_ADC_ANALOGUE_CLK_CONFIG(8, IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_8),
+       IMX7D_ADC_ANALOGUE_CLK_CONFIG(16, IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_16),
+       IMX7D_ADC_ANALOGUE_CLK_CONFIG(32, IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_32),
+       IMX7D_ADC_ANALOGUE_CLK_CONFIG(64, IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_64),
+       IMX7D_ADC_ANALOGUE_CLK_CONFIG(128, IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_128),
+};
+
+#define IMX7D_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 imx7d_adc_iio_channels[] = {
+       IMX7D_ADC_CHAN(0),
+       IMX7D_ADC_CHAN(1),
+       IMX7D_ADC_CHAN(2),
+       IMX7D_ADC_CHAN(3),
+       IMX7D_ADC_CHAN(4),
+       IMX7D_ADC_CHAN(5),
+       IMX7D_ADC_CHAN(6),
+       IMX7D_ADC_CHAN(7),
+       IMX7D_ADC_CHAN(8),
+       IMX7D_ADC_CHAN(9),
+       IMX7D_ADC_CHAN(10),
+       IMX7D_ADC_CHAN(11),
+       IMX7D_ADC_CHAN(12),
+       IMX7D_ADC_CHAN(13),
+       IMX7D_ADC_CHAN(14),
+       IMX7D_ADC_CHAN(15),
+};
+
+static const u32 imx7d_adc_average_num[] = {
+       IMX7D_REG_ADC_CH_CFG2_AVG_NUM_4,
+       IMX7D_REG_ADC_CH_CFG2_AVG_NUM_8,
+       IMX7D_REG_ADC_CH_CFG2_AVG_NUM_16,
+       IMX7D_REG_ADC_CH_CFG2_AVG_NUM_32,
+};
+
+static void imx7d_adc_feature_config(struct imx7d_adc *info)
+{
+       info->adc_feature.clk_pre_div = IMX7D_ADC_ANALOG_CLK_PRE_DIV_4;
+       info->adc_feature.avg_num = IMX7D_ADC_AVERAGE_NUM_32;
+       info->adc_feature.core_time_unit = 1;
+       info->adc_feature.average_en = true;
+}
+
+static void imx7d_adc_sample_rate_set(struct imx7d_adc *info)
+{
+       struct imx7d_adc_feature *adc_feature = &info->adc_feature;
+       struct imx7d_adc_analogue_core_clk adc_analogure_clk;
+       u32 i;
+       u32 tmp_cfg1;
+       u32 sample_rate = 0;
+
+       /*
+        * Before sample set, disable channel A,B,C,D. Here we
+        * clear the bit 31 of register REG_ADC_CH_A\B\C\D_CFG1.
+        */
+       for (i = 0; i < 4; i++) {
+               tmp_cfg1 =
+                       readl(info->regs + i * IMX7D_EACH_CHANNEL_REG_OFFSET);
+               tmp_cfg1 &= ~IMX7D_REG_ADC_CH_CFG1_CHANNEL_EN;
+               writel(tmp_cfg1,
+                      info->regs + i * IMX7D_EACH_CHANNEL_REG_OFFSET);
+       }
+
+       adc_analogure_clk = imx7d_adc_analogue_clk[adc_feature->clk_pre_div];
+       sample_rate |= adc_analogure_clk.reg_config;
+       info->pre_div_num = adc_analogure_clk.pre_div;
+
+       sample_rate |= adc_feature->core_time_unit;
+       writel(sample_rate, info->regs + IMX7D_REG_ADC_TIMER_UNIT);
+}
+
+static void imx7d_adc_hw_init(struct imx7d_adc *info)
+{
+       u32 cfg;
+
+       /* power up and enable adc analogue core */
+       cfg = readl(info->regs + IMX7D_REG_ADC_ADC_CFG);
+       cfg &= ~(IMX7D_REG_ADC_ADC_CFG_ADC_CLK_DOWN |
+                IMX7D_REG_ADC_ADC_CFG_ADC_POWER_DOWN);
+       cfg |= IMX7D_REG_ADC_ADC_CFG_ADC_EN;
+       writel(cfg, info->regs + IMX7D_REG_ADC_ADC_CFG);
+
+       /* enable channel A,B,C,D interrupt */
+       writel(IMX7D_REG_ADC_INT_CHANNEL_INT_EN,
+              info->regs + IMX7D_REG_ADC_INT_SIG_EN);
+       writel(IMX7D_REG_ADC_INT_CHANNEL_INT_EN,
+              info->regs + IMX7D_REG_ADC_INT_EN);
+
+       imx7d_adc_sample_rate_set(info);
+}
+
+static void imx7d_adc_channel_set(struct imx7d_adc *info)
+{
+       u32 cfg1 = 0;
+       u32 cfg2;
+       u32 channel;
+
+       channel = info->channel;
+
+       /* the channel choose single conversion, and enable average mode */
+       cfg1 |= (IMX7D_REG_ADC_CH_CFG1_CHANNEL_EN |
+                IMX7D_REG_ADC_CH_CFG1_CHANNEL_SINGLE);
+       if (info->adc_feature.average_en)
+               cfg1 |= IMX7D_REG_ADC_CH_CFG1_CHANNEL_AVG_EN;
+
+       /*
+        * physical channel 0 chose logical channel A
+        * physical channel 1 chose logical channel B
+        * physical channel 2 chose logical channel C
+        * physical channel 3 chose logical channel D
+        */
+       cfg1 |= IMX7D_REG_ADC_CH_CFG1_CHANNEL_SEL(channel);
+
+       /*
+        * read register REG_ADC_CH_A\B\C\D_CFG2, according to the
+        * channel chosen
+        */
+       cfg2 = readl(info->regs + IMX7D_EACH_CHANNEL_REG_OFFSET * channel +
+                    IMX7D_REG_ADC_CHANNEL_CFG2_BASE);
+
+       cfg2 |= imx7d_adc_average_num[info->adc_feature.avg_num];
+
+       /*
+        * write the register REG_ADC_CH_A\B\C\D_CFG2, according to
+        * the channel chosen
+        */
+       writel(cfg2, info->regs + IMX7D_EACH_CHANNEL_REG_OFFSET * channel +
+              IMX7D_REG_ADC_CHANNEL_CFG2_BASE);
+       writel(cfg1, info->regs + IMX7D_EACH_CHANNEL_REG_OFFSET * channel);
+}
+
+static u32 imx7d_adc_get_sample_rate(struct imx7d_adc *info)
+{
+       /* input clock is always 24MHz */
+       u32 input_clk = 24000000;
+       u32 analogue_core_clk;
+       u32 core_time_unit = info->adc_feature.core_time_unit;
+       u32 tmp;
+
+       analogue_core_clk = input_clk / info->pre_div_num;
+       tmp = (core_time_unit + 1) * 6;
+
+       return analogue_core_clk / tmp;
+}
+
+static int imx7d_adc_read_raw(struct iio_dev *indio_dev,
+                       struct iio_chan_spec const *chan,
+                       int *val,
+                       int *val2,
+                       long mask)
+{
+       struct imx7d_adc *info = iio_priv(indio_dev);
+
+       u32 channel;
+       long ret;
+
+       switch (mask) {
+       case IIO_CHAN_INFO_RAW:
+               mutex_lock(&indio_dev->mlock);
+               reinit_completion(&info->completion);
+
+               channel = chan->channel & 0x03;
+               info->channel = channel;
+               imx7d_adc_channel_set(info);
+
+               ret = wait_for_completion_interruptible_timeout
+                               (&info->completion, IMX7D_ADC_TIMEOUT);
+               if (ret == 0) {
+                       mutex_unlock(&indio_dev->mlock);
+                       return -ETIMEDOUT;
+               }
+               if (ret < 0) {
+                       mutex_unlock(&indio_dev->mlock);
+                       return ret;
+               }
+
+               *val = info->value;
+               mutex_unlock(&indio_dev->mlock);
+               return IIO_VAL_INT;
+
+       case IIO_CHAN_INFO_SCALE:
+               info->vref_uv = regulator_get_voltage(info->vref);
+               *val = info->vref_uv / 1000;
+               *val2 = 12;
+               return IIO_VAL_FRACTIONAL_LOG2;
+
+       case IIO_CHAN_INFO_SAMP_FREQ:
+               *val = imx7d_adc_get_sample_rate(info);
+               return IIO_VAL_INT;
+
+       default:
+               return -EINVAL;
+       }
+}
+
+static int imx7d_adc_read_data(struct imx7d_adc *info)
+{
+       u32 channel;
+       u32 value;
+
+       channel = info->channel & 0x03;
+
+       /*
+        * channel A and B conversion result share one register,
+        * bit[27~16] is the channel B conversion result,
+        * bit[11~0] is the channel A conversion result.
+        * channel C and D is the same.
+        */
+       if (channel < 2)
+               value = readl(info->regs + IMX7D_REG_ADC_CHA_B_CNV_RSLT);
+       else
+               value = readl(info->regs + IMX7D_REG_ADC_CHC_D_CNV_RSLT);
+       if (channel & 0x1)      /* channel B or D */
+               value = (value >> 16) & 0xFFF;
+       else                    /* channel A or C */
+               value &= 0xFFF;
+
+       return value;
+}
+
+static irqreturn_t imx7d_adc_isr(int irq, void *dev_id)
+{
+       struct imx7d_adc *info = (struct imx7d_adc *)dev_id;
+       int status;
+
+       status = readl(info->regs + IMX7D_REG_ADC_INT_STATUS);
+       if (status & IMX7D_REG_ADC_INT_STATUS_CHANNEL_INT_STATUS) {
+               info->value = imx7d_adc_read_data(info);
+               complete(&info->completion);
+
+               /*
+                * The register IMX7D_REG_ADC_INT_STATUS can't clear
+                * itself after read operation, need software to write
+                * 0 to the related bit. Here we clear the channel A/B/C/D
+                * conversion finished flag.
+                */
+               status &= ~IMX7D_REG_ADC_INT_STATUS_CHANNEL_INT_STATUS;
+               writel(status, info->regs + IMX7D_REG_ADC_INT_STATUS);
+       }
+
+       /*
+        * If the channel A/B/C/D conversion timeout, report it and clear these
+        * timeout flags.
+        */
+       if (status & IMX7D_REG_ADC_INT_STATUS_CHANNEL_CONV_TIME_OUT) {
+               pr_err("%s: ADC got conversion time out interrupt: 0x%08x\n",
+                       dev_name(info->dev), status);
+               status &= ~IMX7D_REG_ADC_INT_STATUS_CHANNEL_CONV_TIME_OUT;
+               writel(status, info->regs + IMX7D_REG_ADC_INT_STATUS);
+       }
+
+       return IRQ_HANDLED;
+}
+
+static int imx7d_adc_reg_access(struct iio_dev *indio_dev,
+                       unsigned reg, unsigned writeval,
+                       unsigned *readval)
+{
+       struct imx7d_adc *info = iio_priv(indio_dev);
+
+       if (!readval || reg % 4 || reg > IMX7D_REG_ADC_ADC_CFG)
+               return -EINVAL;
+
+       *readval = readl(info->regs + reg);
+
+       return 0;
+}
+
+static const struct iio_info imx7d_adc_iio_info = {
+       .driver_module = THIS_MODULE,
+       .read_raw = &imx7d_adc_read_raw,
+       .debugfs_reg_access = &imx7d_adc_reg_access,
+};
+
+static const struct of_device_id imx7d_adc_match[] = {
+       { .compatible = "fsl,imx7d-adc", },
+       { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imx7d_adc_match);
+
+static void imx7d_adc_power_down(struct imx7d_adc *info)
+{
+       u32 adc_cfg;
+
+       adc_cfg = readl(info->regs + IMX7D_REG_ADC_ADC_CFG);
+       adc_cfg |= IMX7D_REG_ADC_ADC_CFG_ADC_CLK_DOWN |
+                  IMX7D_REG_ADC_ADC_CFG_ADC_POWER_DOWN;
+       adc_cfg &= ~IMX7D_REG_ADC_ADC_CFG_ADC_EN;
+       writel(adc_cfg, info->regs + IMX7D_REG_ADC_ADC_CFG);
+}
+
+static int imx7d_adc_probe(struct platform_device *pdev)
+{
+       struct imx7d_adc *info;
+       struct iio_dev *indio_dev;
+       struct resource *mem;
+       int irq;
+       int ret;
+
+       indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info));
+       if (!indio_dev) {
+               dev_err(&pdev->dev, "Failed allocating iio device\n");
+               return -ENOMEM;
+       }
+
+       info = iio_priv(indio_dev);
+       info->dev = &pdev->dev;
+
+       mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       info->regs = devm_ioremap_resource(&pdev->dev, mem);
+       if (IS_ERR(info->regs)) {
+               ret = PTR_ERR(info->regs);
+               dev_err(&pdev->dev,
+                       "Failed to remap adc memory, err = %d\n", ret);
+               return ret;
+       }
+
+       irq = platform_get_irq(pdev, 0);
+       if (irq < 0) {
+               dev_err(&pdev->dev, "No irq resource?\n");
+               return irq;
+       }
+
+       info->clk = devm_clk_get(&pdev->dev, "adc");
+       if (IS_ERR(info->clk)) {
+               ret = PTR_ERR(info->clk);
+               dev_err(&pdev->dev, "Failed getting clock, err = %d\n", ret);
+               return ret;
+       }
+
+       info->vref = devm_regulator_get(&pdev->dev, "vref");
+       if (IS_ERR(info->vref)) {
+               ret = PTR_ERR(info->vref);
+               dev_err(&pdev->dev,
+                       "Failed getting reference voltage, err = %d\n", ret);
+               return ret;
+       }
+
+       ret = regulator_enable(info->vref);
+       if (ret) {
+               dev_err(&pdev->dev,
+                       "Can't enable adc reference top voltage, err = %d\n",
+                       ret);
+               return ret;
+       }
+
+       platform_set_drvdata(pdev, indio_dev);
+
+       init_completion(&info->completion);
+
+       indio_dev->name = dev_name(&pdev->dev);
+       indio_dev->dev.parent = &pdev->dev;
+       indio_dev->info = &imx7d_adc_iio_info;
+       indio_dev->modes = INDIO_DIRECT_MODE;
+       indio_dev->channels = imx7d_adc_iio_channels;
+       indio_dev->num_channels = ARRAY_SIZE(imx7d_adc_iio_channels);
+
+       ret = clk_prepare_enable(info->clk);
+       if (ret) {
+               dev_err(&pdev->dev,
+                       "Could not prepare or enable the clock.\n");
+               goto error_adc_clk_enable;
+       }
+
+       ret = devm_request_irq(info->dev, irq,
+                               imx7d_adc_isr, 0,
+                               dev_name(&pdev->dev), info);
+       if (ret < 0) {
+               dev_err(&pdev->dev, "Failed requesting irq, irq = %d\n", irq);
+               goto error_iio_device_register;
+       }
+
+       imx7d_adc_feature_config(info);
+       imx7d_adc_hw_init(info);
+
+       ret = iio_device_register(indio_dev);
+       if (ret) {
+               imx7d_adc_power_down(info);
+               dev_err(&pdev->dev, "Couldn't register the device.\n");
+               goto error_iio_device_register;
+       }
+
+       return 0;
+
+error_iio_device_register:
+       clk_disable_unprepare(info->clk);
+error_adc_clk_enable:
+       regulator_disable(info->vref);
+
+       return ret;
+}
+
+static int imx7d_adc_remove(struct platform_device *pdev)
+{
+       struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+       struct imx7d_adc *info = iio_priv(indio_dev);
+
+       iio_device_unregister(indio_dev);
+
+       imx7d_adc_power_down(info);
+
+       clk_disable_unprepare(info->clk);
+       regulator_disable(info->vref);
+
+       return 0;
+}
+
+static int __maybe_unused imx7d_adc_suspend(struct device *dev)
+{
+       struct iio_dev *indio_dev = dev_get_drvdata(dev);
+       struct imx7d_adc *info = iio_priv(indio_dev);
+
+       imx7d_adc_power_down(info);
+
+       clk_disable_unprepare(info->clk);
+       regulator_disable(info->vref);
+
+       return 0;
+}
+
+static int __maybe_unused imx7d_adc_resume(struct device *dev)
+{
+       struct iio_dev *indio_dev = dev_get_drvdata(dev);
+       struct imx7d_adc *info = iio_priv(indio_dev);
+       int ret;
+
+       ret = regulator_enable(info->vref);
+       if (ret) {
+               dev_err(info->dev,
+                       "Can't enable adc reference top voltage, err = %d\n",
+                       ret);
+               return ret;
+       }
+
+       ret = clk_prepare_enable(info->clk);
+       if (ret) {
+               dev_err(info->dev,
+                       "Could not prepare or enable clock.\n");
+               regulator_disable(info->vref);
+               return ret;
+       }
+
+       imx7d_adc_hw_init(info);
+
+       return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(imx7d_adc_pm_ops, imx7d_adc_suspend, imx7d_adc_resume);
+
+static struct platform_driver imx7d_adc_driver = {
+       .probe          = imx7d_adc_probe,
+       .remove         = imx7d_adc_remove,
+       .driver         = {
+               .name   = "imx7d_adc",
+               .of_match_table = imx7d_adc_match,
+               .pm     = &imx7d_adc_pm_ops,
+       },
+};
+
+module_platform_driver(imx7d_adc_driver);
+
+MODULE_AUTHOR("Haibo Chen <haibo.chen@freescale.com>");
+MODULE_DESCRIPTION("Freeacale IMX7D ADC driver");
+MODULE_LICENSE("GPL v2");