File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/iio/adc/vf610_adc.c b/drivers/iio/adc/vf610_adc.c
new file mode 100644
index 0000000..1dbc214
--- /dev/null
+++ b/drivers/iio/adc/vf610_adc.c
@@ -0,0 +1,993 @@
+/*
+ * Freescale Vybrid vf610 ADC driver
+ *
+ * Copyright 2013 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/regulator/consumer.h>
+#include <linux/of_platform.h>
+#include <linux/err.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
+/* This will be the driver name the kernel reports */
+#define DRIVER_NAME "vf610-adc"
+
+/* Vybrid/IMX ADC registers */
+#define VF610_REG_ADC_HC0		0x00
+#define VF610_REG_ADC_HC1		0x04
+#define VF610_REG_ADC_HS		0x08
+#define VF610_REG_ADC_R0		0x0c
+#define VF610_REG_ADC_R1		0x10
+#define VF610_REG_ADC_CFG		0x14
+#define VF610_REG_ADC_GC		0x18
+#define VF610_REG_ADC_GS		0x1c
+#define VF610_REG_ADC_CV		0x20
+#define VF610_REG_ADC_OFS		0x24
+#define VF610_REG_ADC_CAL		0x28
+#define VF610_REG_ADC_PCTL		0x30
+
+/* Configuration register field define */
+#define VF610_ADC_MODE_BIT8		0x00
+#define VF610_ADC_MODE_BIT10		0x04
+#define VF610_ADC_MODE_BIT12		0x08
+#define VF610_ADC_MODE_MASK		0x0c
+#define VF610_ADC_BUSCLK2_SEL		0x01
+#define VF610_ADC_ALTCLK_SEL		0x02
+#define VF610_ADC_ADACK_SEL		0x03
+#define VF610_ADC_ADCCLK_MASK		0x03
+#define VF610_ADC_CLK_DIV2		0x20
+#define VF610_ADC_CLK_DIV4		0x40
+#define VF610_ADC_CLK_DIV8		0x60
+#define VF610_ADC_CLK_MASK		0x60
+#define VF610_ADC_ADLSMP_LONG		0x10
+#define VF610_ADC_ADSTS_SHORT   0x100
+#define VF610_ADC_ADSTS_NORMAL  0x200
+#define VF610_ADC_ADSTS_LONG    0x300
+#define VF610_ADC_ADSTS_MASK		0x300
+#define VF610_ADC_ADLPC_EN		0x80
+#define VF610_ADC_ADHSC_EN		0x400
+#define VF610_ADC_REFSEL_VALT		0x800
+#define VF610_ADC_REFSEL_VBG		0x1000
+#define VF610_ADC_ADTRG_HARD		0x2000
+#define VF610_ADC_AVGS_8		0x4000
+#define VF610_ADC_AVGS_16		0x8000
+#define VF610_ADC_AVGS_32		0xC000
+#define VF610_ADC_AVGS_MASK		0xC000
+#define VF610_ADC_OVWREN		0x10000
+
+/* General control register field define */
+#define VF610_ADC_ADACKEN		0x1
+#define VF610_ADC_DMAEN			0x2
+#define VF610_ADC_ACREN			0x4
+#define VF610_ADC_ACFGT			0x8
+#define VF610_ADC_ACFE			0x10
+#define VF610_ADC_AVGEN			0x20
+#define VF610_ADC_ADCON			0x40
+#define VF610_ADC_CAL			0x80
+
+/* Other field define */
+#define VF610_ADC_ADCHC(x)		((x) & 0x1F)
+#define VF610_ADC_AIEN			(0x1 << 7)
+#define VF610_ADC_CONV_DISABLE		0x1F
+#define VF610_ADC_HS_COCO0		0x1
+#define VF610_ADC_CALF			0x2
+#define VF610_ADC_TIMEOUT		msecs_to_jiffies(100)
+
+#define DEFAULT_SAMPLE_TIME		1000
+
+/* V at 25°C of 696 mV */
+#define VF610_VTEMP25_3V0		950
+/* V at 25°C of 699 mV */
+#define VF610_VTEMP25_3V3		867
+/* Typical sensor slope coefficient at all temperatures */
+#define VF610_TEMP_SLOPE_COEFF		1840
+
+enum clk_sel {
+	VF610_ADCIOC_BUSCLK_SET,
+	VF610_ADCIOC_ALTCLK_SET,
+	VF610_ADCIOC_ADACK_SET,
+};
+
+enum vol_ref {
+	VF610_ADCIOC_VR_VREF_SET,
+	VF610_ADCIOC_VR_VALT_SET,
+	VF610_ADCIOC_VR_VBG_SET,
+};
+
+enum average_sel {
+	VF610_ADC_SAMPLE_1,
+	VF610_ADC_SAMPLE_4,
+	VF610_ADC_SAMPLE_8,
+	VF610_ADC_SAMPLE_16,
+	VF610_ADC_SAMPLE_32,
+};
+
+enum conversion_mode_sel {
+	VF610_ADC_CONV_NORMAL,
+	VF610_ADC_CONV_HIGH_SPEED,
+	VF610_ADC_CONV_LOW_POWER,
+};
+
+enum lst_adder_sel {
+	VF610_ADCK_CYCLES_3,
+	VF610_ADCK_CYCLES_5,
+	VF610_ADCK_CYCLES_7,
+	VF610_ADCK_CYCLES_9,
+	VF610_ADCK_CYCLES_13,
+	VF610_ADCK_CYCLES_17,
+	VF610_ADCK_CYCLES_21,
+	VF610_ADCK_CYCLES_25,
+};
+
+struct vf610_adc_feature {
+	enum clk_sel	clk_sel;
+	enum vol_ref	vol_ref;
+	enum conversion_mode_sel conv_mode;
+
+	int	clk_div;
+	int     sample_rate;
+	int	res_mode;
+	u32 lst_adder_index;
+	u32 default_sample_time;
+
+	bool	calibration;
+	bool	ovwren;
+};
+
+struct vf610_adc {
+	struct device *dev;
+	void __iomem *regs;
+	struct clk *clk;
+
+	u32 vref_uv;
+	u32 value;
+	struct regulator *vref;
+
+	u32 max_adck_rate[3];
+	struct vf610_adc_feature adc_feature;
+
+	u32 sample_freq_avail[5];
+
+	struct completion completion;
+	u16 buffer[8];
+};
+
+static const u32 vf610_hw_avgs[] = { 1, 4, 8, 16, 32 };
+static const u32 vf610_lst_adder[] = { 3, 5, 7, 9, 13, 17, 21, 25 };
+
+static inline void vf610_adc_calculate_rates(struct vf610_adc *info)
+{
+	struct vf610_adc_feature *adc_feature = &info->adc_feature;
+	unsigned long adck_rate, ipg_rate = clk_get_rate(info->clk);
+	u32 adck_period, lst_addr_min;
+	int divisor, i;
+
+	adck_rate = info->max_adck_rate[adc_feature->conv_mode];
+
+	if (adck_rate) {
+		/* calculate clk divider which is within specification */
+		divisor = ipg_rate / adck_rate;
+		adc_feature->clk_div = 1 << fls(divisor + 1);
+	} else {
+		/* fall-back value using a safe divisor */
+		adc_feature->clk_div = 8;
+	}
+
+	adck_rate = ipg_rate / adc_feature->clk_div;
+
+	/*
+	 * Determine the long sample time adder value to be used based
+	 * on the default minimum sample time provided.
+	 */
+	adck_period = NSEC_PER_SEC / adck_rate;
+	lst_addr_min = adc_feature->default_sample_time / adck_period;
+	for (i = 0; i < ARRAY_SIZE(vf610_lst_adder); i++) {
+		if (vf610_lst_adder[i] > lst_addr_min) {
+			adc_feature->lst_adder_index = i;
+			break;
+		}
+	}
+
+	/*
+	 * Calculate ADC sample frequencies
+	 * Sample time unit is ADCK cycles. ADCK clk source is ipg clock,
+	 * which is the same as bus clock.
+	 *
+	 * ADC conversion time = SFCAdder + AverageNum x (BCT + LSTAdder)
+	 * SFCAdder: fixed to 6 ADCK cycles
+	 * AverageNum: 1, 4, 8, 16, 32 samples for hardware average.
+	 * BCT (Base Conversion Time): fixed to 25 ADCK cycles for 12 bit mode
+	 * LSTAdder(Long Sample Time): 3, 5, 7, 9, 13, 17, 21, 25 ADCK cycles
+	 */
+	for (i = 0; i < ARRAY_SIZE(vf610_hw_avgs); i++)
+		info->sample_freq_avail[i] =
+			adck_rate / (6 + vf610_hw_avgs[i] *
+			 (25 + vf610_lst_adder[adc_feature->lst_adder_index]));
+}
+
+static inline void vf610_adc_cfg_init(struct vf610_adc *info)
+{
+	struct vf610_adc_feature *adc_feature = &info->adc_feature;
+
+	/* set default Configuration for ADC controller */
+	adc_feature->clk_sel = VF610_ADCIOC_BUSCLK_SET;
+	adc_feature->vol_ref = VF610_ADCIOC_VR_VREF_SET;
+
+	adc_feature->calibration = true;
+	adc_feature->ovwren = true;
+
+	adc_feature->res_mode = 12;
+	adc_feature->sample_rate = 1;
+
+	adc_feature->conv_mode = VF610_ADC_CONV_LOW_POWER;
+
+	vf610_adc_calculate_rates(info);
+}
+
+static void vf610_adc_cfg_post_set(struct vf610_adc *info)
+{
+	struct vf610_adc_feature *adc_feature = &info->adc_feature;
+	int cfg_data = 0;
+	int gc_data = 0;
+
+	switch (adc_feature->clk_sel) {
+	case VF610_ADCIOC_ALTCLK_SET:
+		cfg_data |= VF610_ADC_ALTCLK_SEL;
+		break;
+	case VF610_ADCIOC_ADACK_SET:
+		cfg_data |= VF610_ADC_ADACK_SEL;
+		break;
+	default:
+		break;
+	}
+
+	/* low power set for calibration */
+	cfg_data |= VF610_ADC_ADLPC_EN;
+
+	/* enable high speed for calibration */
+	cfg_data |= VF610_ADC_ADHSC_EN;
+
+	/* voltage reference */
+	switch (adc_feature->vol_ref) {
+	case VF610_ADCIOC_VR_VREF_SET:
+		break;
+	case VF610_ADCIOC_VR_VALT_SET:
+		cfg_data |= VF610_ADC_REFSEL_VALT;
+		break;
+	case VF610_ADCIOC_VR_VBG_SET:
+		cfg_data |= VF610_ADC_REFSEL_VBG;
+		break;
+	default:
+		dev_err(info->dev, "error voltage reference\n");
+	}
+
+	/* data overwrite enable */
+	if (adc_feature->ovwren)
+		cfg_data |= VF610_ADC_OVWREN;
+
+	writel(cfg_data, info->regs + VF610_REG_ADC_CFG);
+	writel(gc_data, info->regs + VF610_REG_ADC_GC);
+}
+
+static void vf610_adc_calibration(struct vf610_adc *info)
+{
+	int adc_gc, hc_cfg;
+
+	if (!info->adc_feature.calibration)
+		return;
+
+	/* enable calibration interrupt */
+	hc_cfg = VF610_ADC_AIEN | VF610_ADC_CONV_DISABLE;
+	writel(hc_cfg, info->regs + VF610_REG_ADC_HC0);
+
+	adc_gc = readl(info->regs + VF610_REG_ADC_GC);
+	writel(adc_gc | VF610_ADC_CAL, info->regs + VF610_REG_ADC_GC);
+
+	if (!wait_for_completion_timeout(&info->completion, VF610_ADC_TIMEOUT))
+		dev_err(info->dev, "Timeout for adc calibration\n");
+
+	adc_gc = readl(info->regs + VF610_REG_ADC_GS);
+	if (adc_gc & VF610_ADC_CALF)
+		dev_err(info->dev, "ADC calibration failed\n");
+
+	info->adc_feature.calibration = false;
+}
+
+static void vf610_adc_cfg_set(struct vf610_adc *info)
+{
+	struct vf610_adc_feature *adc_feature = &(info->adc_feature);
+	int cfg_data;
+
+	cfg_data = readl(info->regs + VF610_REG_ADC_CFG);
+
+	cfg_data &= ~VF610_ADC_ADLPC_EN;
+	if (adc_feature->conv_mode == VF610_ADC_CONV_LOW_POWER)
+		cfg_data |= VF610_ADC_ADLPC_EN;
+
+	cfg_data &= ~VF610_ADC_ADHSC_EN;
+	if (adc_feature->conv_mode == VF610_ADC_CONV_HIGH_SPEED)
+		cfg_data |= VF610_ADC_ADHSC_EN;
+
+	writel(cfg_data, info->regs + VF610_REG_ADC_CFG);
+}
+
+static void vf610_adc_sample_set(struct vf610_adc *info)
+{
+	struct vf610_adc_feature *adc_feature = &(info->adc_feature);
+	int cfg_data, gc_data;
+
+	cfg_data = readl(info->regs + VF610_REG_ADC_CFG);
+	gc_data = readl(info->regs + VF610_REG_ADC_GC);
+
+	/* resolution mode */
+	cfg_data &= ~VF610_ADC_MODE_MASK;
+	switch (adc_feature->res_mode) {
+	case 8:
+		cfg_data |= VF610_ADC_MODE_BIT8;
+		break;
+	case 10:
+		cfg_data |= VF610_ADC_MODE_BIT10;
+		break;
+	case 12:
+		cfg_data |= VF610_ADC_MODE_BIT12;
+		break;
+	default:
+		dev_err(info->dev, "error resolution mode\n");
+		break;
+	}
+
+	/* clock select and clock divider */
+	cfg_data &= ~(VF610_ADC_CLK_MASK | VF610_ADC_ADCCLK_MASK);
+	switch (adc_feature->clk_div) {
+	case 1:
+		break;
+	case 2:
+		cfg_data |= VF610_ADC_CLK_DIV2;
+		break;
+	case 4:
+		cfg_data |= VF610_ADC_CLK_DIV4;
+		break;
+	case 8:
+		cfg_data |= VF610_ADC_CLK_DIV8;
+		break;
+	case 16:
+		switch (adc_feature->clk_sel) {
+		case VF610_ADCIOC_BUSCLK_SET:
+			cfg_data |= VF610_ADC_BUSCLK2_SEL | VF610_ADC_CLK_DIV8;
+			break;
+		default:
+			dev_err(info->dev, "error clk divider\n");
+			break;
+		}
+		break;
+	}
+
+	/*
+	 * Set ADLSMP and ADSTS based on the Long Sample Time Adder value
+	 * determined.
+	 */
+	switch (adc_feature->lst_adder_index) {
+	case VF610_ADCK_CYCLES_3:
+		break;
+	case VF610_ADCK_CYCLES_5:
+		cfg_data |= VF610_ADC_ADSTS_SHORT;
+		break;
+	case VF610_ADCK_CYCLES_7:
+		cfg_data |= VF610_ADC_ADSTS_NORMAL;
+		break;
+	case VF610_ADCK_CYCLES_9:
+		cfg_data |= VF610_ADC_ADSTS_LONG;
+		break;
+	case VF610_ADCK_CYCLES_13:
+		cfg_data |= VF610_ADC_ADLSMP_LONG;
+		break;
+	case VF610_ADCK_CYCLES_17:
+		cfg_data |= VF610_ADC_ADLSMP_LONG;
+		cfg_data |= VF610_ADC_ADSTS_SHORT;
+		break;
+	case VF610_ADCK_CYCLES_21:
+		cfg_data |= VF610_ADC_ADLSMP_LONG;
+		cfg_data |= VF610_ADC_ADSTS_NORMAL;
+		break;
+	case VF610_ADCK_CYCLES_25:
+		cfg_data |= VF610_ADC_ADLSMP_LONG;
+		cfg_data |= VF610_ADC_ADSTS_NORMAL;
+		break;
+	default:
+		dev_err(info->dev, "error in sample time select\n");
+	}
+
+	/* update hardware average selection */
+	cfg_data &= ~VF610_ADC_AVGS_MASK;
+	gc_data &= ~VF610_ADC_AVGEN;
+	switch (adc_feature->sample_rate) {
+	case VF610_ADC_SAMPLE_1:
+		break;
+	case VF610_ADC_SAMPLE_4:
+		gc_data |= VF610_ADC_AVGEN;
+		break;
+	case VF610_ADC_SAMPLE_8:
+		gc_data |= VF610_ADC_AVGEN;
+		cfg_data |= VF610_ADC_AVGS_8;
+		break;
+	case VF610_ADC_SAMPLE_16:
+		gc_data |= VF610_ADC_AVGEN;
+		cfg_data |= VF610_ADC_AVGS_16;
+		break;
+	case VF610_ADC_SAMPLE_32:
+		gc_data |= VF610_ADC_AVGEN;
+		cfg_data |= VF610_ADC_AVGS_32;
+		break;
+	default:
+		dev_err(info->dev,
+			"error hardware sample average select\n");
+	}
+
+	writel(cfg_data, info->regs + VF610_REG_ADC_CFG);
+	writel(gc_data, info->regs + VF610_REG_ADC_GC);
+}
+
+static void vf610_adc_hw_init(struct vf610_adc *info)
+{
+	/* CFG: Feature set */
+	vf610_adc_cfg_post_set(info);
+	vf610_adc_sample_set(info);
+
+	/* adc calibration */
+	vf610_adc_calibration(info);
+
+	/* CFG: power and speed set */
+	vf610_adc_cfg_set(info);
+}
+
+static int vf610_set_conversion_mode(struct iio_dev *indio_dev,
+				     const struct iio_chan_spec *chan,
+				     unsigned int mode)
+{
+	struct vf610_adc *info = iio_priv(indio_dev);
+
+	mutex_lock(&indio_dev->mlock);
+	info->adc_feature.conv_mode = mode;
+	vf610_adc_calculate_rates(info);
+	vf610_adc_hw_init(info);
+	mutex_unlock(&indio_dev->mlock);
+
+	return 0;
+}
+
+static int vf610_get_conversion_mode(struct iio_dev *indio_dev,
+				     const struct iio_chan_spec *chan)
+{
+	struct vf610_adc *info = iio_priv(indio_dev);
+
+	return info->adc_feature.conv_mode;
+}
+
+static const char * const vf610_conv_modes[] = { "normal", "high-speed",
+						 "low-power" };
+
+static const struct iio_enum vf610_conversion_mode = {
+	.items = vf610_conv_modes,
+	.num_items = ARRAY_SIZE(vf610_conv_modes),
+	.get = vf610_get_conversion_mode,
+	.set = vf610_set_conversion_mode,
+};
+
+static const struct iio_chan_spec_ext_info vf610_ext_info[] = {
+	IIO_ENUM("conversion_mode", IIO_SHARED_BY_DIR, &vf610_conversion_mode),
+	{},
+};
+
+#define VF610_ADC_CHAN(_idx, _chan_type) {			\
+	.type = (_chan_type),					\
+	.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),	\
+	.ext_info = vf610_ext_info,				\
+	.scan_index = (_idx),			\
+	.scan_type = {					\
+		.sign = 'u',				\
+		.realbits = 12,				\
+		.storagebits = 16,			\
+	},						\
+}
+
+#define VF610_ADC_TEMPERATURE_CHAN(_idx, _chan_type) {	\
+	.type = (_chan_type),	\
+	.channel = (_idx),		\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),	\
+	.scan_index = (_idx),					\
+	.scan_type = {						\
+		.sign = 'u',					\
+		.realbits = 12,					\
+		.storagebits = 16,				\
+	},							\
+}
+
+static const struct iio_chan_spec vf610_adc_iio_channels[] = {
+	VF610_ADC_CHAN(0, IIO_VOLTAGE),
+	VF610_ADC_CHAN(1, IIO_VOLTAGE),
+	VF610_ADC_CHAN(2, IIO_VOLTAGE),
+	VF610_ADC_CHAN(3, IIO_VOLTAGE),
+	VF610_ADC_CHAN(4, IIO_VOLTAGE),
+	VF610_ADC_CHAN(5, IIO_VOLTAGE),
+	VF610_ADC_CHAN(6, IIO_VOLTAGE),
+	VF610_ADC_CHAN(7, IIO_VOLTAGE),
+	VF610_ADC_CHAN(8, IIO_VOLTAGE),
+	VF610_ADC_CHAN(9, IIO_VOLTAGE),
+	VF610_ADC_CHAN(10, IIO_VOLTAGE),
+	VF610_ADC_CHAN(11, IIO_VOLTAGE),
+	VF610_ADC_CHAN(12, IIO_VOLTAGE),
+	VF610_ADC_CHAN(13, IIO_VOLTAGE),
+	VF610_ADC_CHAN(14, IIO_VOLTAGE),
+	VF610_ADC_CHAN(15, IIO_VOLTAGE),
+	VF610_ADC_TEMPERATURE_CHAN(26, IIO_TEMP),
+	IIO_CHAN_SOFT_TIMESTAMP(32),
+	/* sentinel */
+};
+
+static int vf610_adc_read_data(struct vf610_adc *info)
+{
+	int result;
+
+	result = readl(info->regs + VF610_REG_ADC_R0);
+
+	switch (info->adc_feature.res_mode) {
+	case 8:
+		result &= 0xFF;
+		break;
+	case 10:
+		result &= 0x3FF;
+		break;
+	case 12:
+		result &= 0xFFF;
+		break;
+	default:
+		break;
+	}
+
+	return result;
+}
+
+static irqreturn_t vf610_adc_isr(int irq, void *dev_id)
+{
+	struct iio_dev *indio_dev = (struct iio_dev *)dev_id;
+	struct vf610_adc *info = iio_priv(indio_dev);
+	int coco;
+
+	coco = readl(info->regs + VF610_REG_ADC_HS);
+	if (coco & VF610_ADC_HS_COCO0) {
+		info->value = vf610_adc_read_data(info);
+		if (iio_buffer_enabled(indio_dev)) {
+			info->buffer[0] = info->value;
+			iio_push_to_buffers_with_timestamp(indio_dev,
+					info->buffer, iio_get_time_ns());
+			iio_trigger_notify_done(indio_dev->trig);
+		} else
+			complete(&info->completion);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static ssize_t vf610_show_samp_freq_avail(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct vf610_adc *info = iio_priv(dev_to_iio_dev(dev));
+	size_t len = 0;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(info->sample_freq_avail); i++)
+		len += scnprintf(buf + len, PAGE_SIZE - len,
+			"%u ", info->sample_freq_avail[i]);
+
+	/* replace trailing space by newline */
+	buf[len - 1] = '\n';
+
+	return len;
+}
+
+static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(vf610_show_samp_freq_avail);
+
+static struct attribute *vf610_attributes[] = {
+	&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group vf610_attribute_group = {
+	.attrs = vf610_attributes,
+};
+
+static int vf610_read_raw(struct iio_dev *indio_dev,
+			struct iio_chan_spec const *chan,
+			int *val,
+			int *val2,
+			long mask)
+{
+	struct vf610_adc *info = iio_priv(indio_dev);
+	unsigned int hc_cfg;
+	long ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+	case IIO_CHAN_INFO_PROCESSED:
+		mutex_lock(&indio_dev->mlock);
+		if (iio_buffer_enabled(indio_dev)) {
+			mutex_unlock(&indio_dev->mlock);
+			return -EBUSY;
+		}
+
+		reinit_completion(&info->completion);
+		hc_cfg = VF610_ADC_ADCHC(chan->channel);
+		hc_cfg |= VF610_ADC_AIEN;
+		writel(hc_cfg, info->regs + VF610_REG_ADC_HC0);
+		ret = wait_for_completion_interruptible_timeout
+				(&info->completion, VF610_ADC_TIMEOUT);
+		if (ret == 0) {
+			mutex_unlock(&indio_dev->mlock);
+			return -ETIMEDOUT;
+		}
+		if (ret < 0) {
+			mutex_unlock(&indio_dev->mlock);
+			return ret;
+		}
+
+		switch (chan->type) {
+		case IIO_VOLTAGE:
+			*val = info->value;
+			break;
+		case IIO_TEMP:
+			/*
+			 * Calculate in degree Celsius times 1000
+			 * Using the typical sensor slope of 1.84 mV/°C
+			 * and VREFH_ADC at 3.3V, V at 25°C of 699 mV
+			 */
+			*val = 25000 - ((int)info->value - VF610_VTEMP25_3V3) *
+					1000000 / VF610_TEMP_SLOPE_COEFF;
+
+			break;
+		default:
+			mutex_unlock(&indio_dev->mlock);
+			return -EINVAL;
+		}
+
+		mutex_unlock(&indio_dev->mlock);
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_SCALE:
+		*val = info->vref_uv / 1000;
+		*val2 = info->adc_feature.res_mode;
+		return IIO_VAL_FRACTIONAL_LOG2;
+
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		*val = info->sample_freq_avail[info->adc_feature.sample_rate];
+		*val2 = 0;
+		return IIO_VAL_INT;
+
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static int vf610_write_raw(struct iio_dev *indio_dev,
+			struct iio_chan_spec const *chan,
+			int val,
+			int val2,
+			long mask)
+{
+	struct vf610_adc *info = iio_priv(indio_dev);
+	int i;
+
+	switch (mask) {
+		case IIO_CHAN_INFO_SAMP_FREQ:
+			for (i = 0;
+				i < ARRAY_SIZE(info->sample_freq_avail);
+				i++)
+				if (val == info->sample_freq_avail[i]) {
+					info->adc_feature.sample_rate = i;
+					vf610_adc_sample_set(info);
+					return 0;
+				}
+			break;
+
+		default:
+			break;
+	}
+
+	return -EINVAL;
+}
+
+static int vf610_adc_buffer_postenable(struct iio_dev *indio_dev)
+{
+	struct vf610_adc *info = iio_priv(indio_dev);
+	unsigned int channel;
+	int ret;
+	int val;
+
+	ret = iio_triggered_buffer_postenable(indio_dev);
+	if (ret)
+		return ret;
+
+	val = readl(info->regs + VF610_REG_ADC_GC);
+	val |= VF610_ADC_ADCON;
+	writel(val, info->regs + VF610_REG_ADC_GC);
+
+	channel = find_first_bit(indio_dev->active_scan_mask,
+						indio_dev->masklength);
+
+	val = VF610_ADC_ADCHC(channel);
+	val |= VF610_ADC_AIEN;
+
+	writel(val, info->regs + VF610_REG_ADC_HC0);
+
+	return 0;
+}
+
+static int vf610_adc_buffer_predisable(struct iio_dev *indio_dev)
+{
+	struct vf610_adc *info = iio_priv(indio_dev);
+	unsigned int hc_cfg = 0;
+	int val;
+
+	val = readl(info->regs + VF610_REG_ADC_GC);
+	val &= ~VF610_ADC_ADCON;
+	writel(val, info->regs + VF610_REG_ADC_GC);
+
+	hc_cfg |= VF610_ADC_CONV_DISABLE;
+	hc_cfg &= ~VF610_ADC_AIEN;
+
+	writel(hc_cfg, info->regs + VF610_REG_ADC_HC0);
+
+	return iio_triggered_buffer_predisable(indio_dev);
+}
+
+static const struct iio_buffer_setup_ops iio_triggered_buffer_setup_ops = {
+	.postenable = &vf610_adc_buffer_postenable,
+	.predisable = &vf610_adc_buffer_predisable,
+	.validate_scan_mask = &iio_validate_scan_mask_onehot,
+};
+
+static int vf610_adc_reg_access(struct iio_dev *indio_dev,
+			unsigned reg, unsigned writeval,
+			unsigned *readval)
+{
+	struct vf610_adc *info = iio_priv(indio_dev);
+
+	if ((readval == NULL) ||
+		((reg % 4) || (reg > VF610_REG_ADC_PCTL)))
+		return -EINVAL;
+
+	*readval = readl(info->regs + reg);
+
+	return 0;
+}
+
+static const struct iio_info vf610_adc_iio_info = {
+	.driver_module = THIS_MODULE,
+	.read_raw = &vf610_read_raw,
+	.write_raw = &vf610_write_raw,
+	.debugfs_reg_access = &vf610_adc_reg_access,
+	.attrs = &vf610_attribute_group,
+};
+
+static const struct of_device_id vf610_adc_match[] = {
+	{ .compatible = "fsl,vf610-adc", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, vf610_adc_match);
+
+static int vf610_adc_probe(struct platform_device *pdev)
+{
+	struct vf610_adc *info;
+	struct iio_dev *indio_dev;
+	struct resource *mem;
+	int irq;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(struct vf610_adc));
+	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))
+		return PTR_ERR(info->regs);
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "no irq resource?\n");
+		return irq;
+	}
+
+	ret = devm_request_irq(info->dev, irq,
+				vf610_adc_isr, 0,
+				dev_name(&pdev->dev), indio_dev);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed requesting irq, irq = %d\n", irq);
+		return ret;
+	}
+
+	info->clk = devm_clk_get(&pdev->dev, "adc");
+	if (IS_ERR(info->clk)) {
+		dev_err(&pdev->dev, "failed getting clock, err = %ld\n",
+						PTR_ERR(info->clk));
+		return PTR_ERR(info->clk);
+	}
+
+	info->vref = devm_regulator_get(&pdev->dev, "vref");
+	if (IS_ERR(info->vref))
+		return PTR_ERR(info->vref);
+
+	ret = regulator_enable(info->vref);
+	if (ret)
+		return ret;
+
+	info->vref_uv = regulator_get_voltage(info->vref);
+
+	of_property_read_u32_array(pdev->dev.of_node, "fsl,adck-max-frequency",
+			info->max_adck_rate, 3);
+
+	ret = of_property_read_u32(pdev->dev.of_node, "min-sample-time",
+			&info->adc_feature.default_sample_time);
+	if (ret)
+		info->adc_feature.default_sample_time = DEFAULT_SAMPLE_TIME;
+
+	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->dev.of_node = pdev->dev.of_node;
+	indio_dev->info = &vf610_adc_iio_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = vf610_adc_iio_channels;
+	indio_dev->num_channels = ARRAY_SIZE(vf610_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;
+	}
+
+	vf610_adc_cfg_init(info);
+	vf610_adc_hw_init(info);
+
+	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
+					NULL, &iio_triggered_buffer_setup_ops);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Couldn't initialise the buffer\n");
+		goto error_iio_device_register;
+	}
+
+	ret = iio_device_register(indio_dev);
+	if (ret) {
+		dev_err(&pdev->dev, "Couldn't register the device.\n");
+		goto error_adc_buffer_init;
+	}
+
+	return 0;
+
+error_adc_buffer_init:
+	iio_triggered_buffer_cleanup(indio_dev);
+error_iio_device_register:
+	clk_disable_unprepare(info->clk);
+error_adc_clk_enable:
+	regulator_disable(info->vref);
+
+	return ret;
+}
+
+static int vf610_adc_remove(struct platform_device *pdev)
+{
+	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+	struct vf610_adc *info = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+	iio_triggered_buffer_cleanup(indio_dev);
+	regulator_disable(info->vref);
+	clk_disable_unprepare(info->clk);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int vf610_adc_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct vf610_adc *info = iio_priv(indio_dev);
+	int hc_cfg;
+
+	/* ADC controller enters to stop mode */
+	hc_cfg = readl(info->regs + VF610_REG_ADC_HC0);
+	hc_cfg |= VF610_ADC_CONV_DISABLE;
+	writel(hc_cfg, info->regs + VF610_REG_ADC_HC0);
+
+	clk_disable_unprepare(info->clk);
+	regulator_disable(info->vref);
+
+	return 0;
+}
+
+static int vf610_adc_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct vf610_adc *info = iio_priv(indio_dev);
+	int ret;
+
+	ret = regulator_enable(info->vref);
+	if (ret)
+		return ret;
+
+	ret = clk_prepare_enable(info->clk);
+	if (ret)
+		goto disable_reg;
+
+	vf610_adc_hw_init(info);
+
+	return 0;
+
+disable_reg:
+	regulator_disable(info->vref);
+	return ret;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(vf610_adc_pm_ops, vf610_adc_suspend, vf610_adc_resume);
+
+static struct platform_driver vf610_adc_driver = {
+	.probe          = vf610_adc_probe,
+	.remove         = vf610_adc_remove,
+	.driver         = {
+		.name   = DRIVER_NAME,
+		.of_match_table = vf610_adc_match,
+		.pm     = &vf610_adc_pm_ops,
+	},
+};
+
+module_platform_driver(vf610_adc_driver);
+
+MODULE_AUTHOR("Fugang Duan <B38611@freescale.com>");
+MODULE_DESCRIPTION("Freescale VF610 ADC driver");
+MODULE_LICENSE("GPL v2");