drivers/staging/iio/meter/ade7754.c - nest-learning-thermostat/6.0/linux-imx-4.9.88 - Git at Google

 /*
  * ADE7754 Polyphase Multifunction Energy Metering IC Driver
  *
  * Copyright 2010 Analog Devices Inc.
  *
  * Licensed under the GPL-2 or later.
  */

 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/delay.h>
 #include <linux/mutex.h>
 #include <linux/device.h>
 #include <linux/kernel.h>
 #include <linux/spi/spi.h>
 #include <linux/slab.h>
 #include <linux/sysfs.h>
 #include <linux/list.h>
 #include <linux/module.h>

 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
 #include "meter.h"
 #include "ade7754.h"

 static int ade7754_spi_write_reg_8(struct device *dev, u8 reg_address, u8 val)
 {
 	int ret;
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct ade7754_state *st = iio_priv(indio_dev);

 	mutex_lock(&st->buf_lock);
 	st->tx[0] = ADE7754_WRITE_REG(reg_address);
 	st->tx[1] = val;

 	ret = spi_write(st->us, st->tx, 2);
 	mutex_unlock(&st->buf_lock);

 	return ret;
 }

 static int ade7754_spi_write_reg_16(struct device *dev,
 				    u8 reg_address, u16 value)
 {
 	int ret;
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct ade7754_state *st = iio_priv(indio_dev);

 	mutex_lock(&st->buf_lock);
 	st->tx[0] = ADE7754_WRITE_REG(reg_address);
 	st->tx[1] = (value >> 8) & 0xFF;
 	st->tx[2] = value & 0xFF;
 	ret = spi_write(st->us, st->tx, 3);
 	mutex_unlock(&st->buf_lock);

 	return ret;
 }

 static int ade7754_spi_read_reg_8(struct device *dev, u8 reg_address, u8 *val)
 {
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct ade7754_state *st = iio_priv(indio_dev);
 	int ret;

 	ret = spi_w8r8(st->us, ADE7754_READ_REG(reg_address));
 	if (ret < 0) {
 		dev_err(&st->us->dev, "problem when reading 8 bit register 0x%02X",
 			reg_address);
 		return ret;
 	}
 	*val = ret;

 	return 0;
 }

 static int ade7754_spi_read_reg_16(struct device *dev,
 				   u8 reg_address, u16 *val)
 {
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct ade7754_state *st = iio_priv(indio_dev);
 	int ret;

 	ret = spi_w8r16be(st->us, ADE7754_READ_REG(reg_address));
 	if (ret < 0) {
 		dev_err(&st->us->dev, "problem when reading 16 bit register 0x%02X",
 			reg_address);
 		return ret;
 	}

 	*val = ret;

 	return 0;
 }

 static int ade7754_spi_read_reg_24(struct device *dev,
 				   u8 reg_address, u32 *val)
 {
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct ade7754_state *st = iio_priv(indio_dev);
 	int ret;
 	struct spi_transfer xfers[] = {
 		{
 			.tx_buf = st->tx,
 			.rx_buf = st->rx,
 			.bits_per_word = 8,
 			.len = 4,
 		},
 	};

 	mutex_lock(&st->buf_lock);
 	st->tx[0] = ADE7754_READ_REG(reg_address);
 	st->tx[1] = 0;
 	st->tx[2] = 0;
 	st->tx[3] = 0;

 	ret = spi_sync_transfer(st->us, xfers, ARRAY_SIZE(xfers));
 	if (ret) {
 		dev_err(&st->us->dev, "problem when reading 24 bit register 0x%02X",
 			reg_address);
 		goto error_ret;
 	}
 	*val = (st->rx[1] << 16) | (st->rx[2] << 8) | st->rx[3];

 error_ret:
 	mutex_unlock(&st->buf_lock);
 	return ret;
 }

 static ssize_t ade7754_read_8bit(struct device *dev,
 				 struct device_attribute *attr,
 				 char *buf)
 {
 	int ret;
 	u8 val = 0;
 	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);

 	ret = ade7754_spi_read_reg_8(dev, this_attr->address, &val);
 	if (ret)
 		return ret;

 	return sprintf(buf, "%u\n", val);
 }

 static ssize_t ade7754_read_16bit(struct device *dev,
 				  struct device_attribute *attr,
 				  char *buf)
 {
 	int ret;
 	u16 val = 0;
 	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);

 	ret = ade7754_spi_read_reg_16(dev, this_attr->address, &val);
 	if (ret)
 		return ret;

 	return sprintf(buf, "%u\n", val);
 }

 static ssize_t ade7754_read_24bit(struct device *dev,
 				  struct device_attribute *attr,
 				  char *buf)
 {
 	int ret;
 	u32 val = 0;
 	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);

 	ret = ade7754_spi_read_reg_24(dev, this_attr->address, &val);
 	if (ret)
 		return ret;

 	return sprintf(buf, "%u\n", val & 0xFFFFFF);
 }

 static ssize_t ade7754_write_8bit(struct device *dev,
 				  struct device_attribute *attr,
 				  const char *buf,
 				  size_t len)
 {
 	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 	int ret;
 	u8 val;

 	ret = kstrtou8(buf, 10, &val);
 	if (ret)
 		goto error_ret;
 	ret = ade7754_spi_write_reg_8(dev, this_attr->address, val);

 error_ret:
 	return ret ? ret : len;
 }

 static ssize_t ade7754_write_16bit(struct device *dev,
 				   struct device_attribute *attr,
 				   const char *buf,
 				   size_t len)
 {
 	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 	int ret;
 	u16 val;

 	ret = kstrtou16(buf, 10, &val);
 	if (ret)
 		goto error_ret;
 	ret = ade7754_spi_write_reg_16(dev, this_attr->address, val);

 error_ret:
 	return ret ? ret : len;
 }

 static int ade7754_reset(struct device *dev)
 {
 	int ret;
 	u8 val;

 	ret = ade7754_spi_read_reg_8(dev, ADE7754_OPMODE, &val);
 	if (ret < 0)
 		return ret;

 	val |= BIT(6); /* Software Chip Reset */
 	return ade7754_spi_write_reg_8(dev, ADE7754_OPMODE, val);
 }

 static IIO_DEV_ATTR_AENERGY(ade7754_read_24bit, ADE7754_AENERGY);
 static IIO_DEV_ATTR_LAENERGY(ade7754_read_24bit, ADE7754_LAENERGY);
 static IIO_DEV_ATTR_VAENERGY(ade7754_read_24bit, ADE7754_VAENERGY);
 static IIO_DEV_ATTR_LVAENERGY(ade7754_read_24bit, ADE7754_LVAENERGY);
 static IIO_DEV_ATTR_VPEAK(S_IWUSR | S_IRUGO,
 		ade7754_read_8bit,
 		ade7754_write_8bit,
 		ADE7754_VPEAK);
 static IIO_DEV_ATTR_IPEAK(S_IWUSR | S_IRUGO,
 		ade7754_read_8bit,
 		ade7754_write_8bit,
 		ADE7754_VPEAK);
 static IIO_DEV_ATTR_APHCAL(S_IWUSR | S_IRUGO,
 		ade7754_read_8bit,
 		ade7754_write_8bit,
 		ADE7754_APHCAL);
 static IIO_DEV_ATTR_BPHCAL(S_IWUSR | S_IRUGO,
 		ade7754_read_8bit,
 		ade7754_write_8bit,
 		ADE7754_BPHCAL);
 static IIO_DEV_ATTR_CPHCAL(S_IWUSR | S_IRUGO,
 		ade7754_read_8bit,
 		ade7754_write_8bit,
 		ADE7754_CPHCAL);
 static IIO_DEV_ATTR_AAPOS(S_IWUSR | S_IRUGO,
 		ade7754_read_16bit,
 		ade7754_write_16bit,
 		ADE7754_AAPOS);
 static IIO_DEV_ATTR_BAPOS(S_IWUSR | S_IRUGO,
 		ade7754_read_16bit,
 		ade7754_write_16bit,
 		ADE7754_BAPOS);
 static IIO_DEV_ATTR_CAPOS(S_IWUSR | S_IRUGO,
 		ade7754_read_16bit,
 		ade7754_write_16bit,
 		ADE7754_CAPOS);
 static IIO_DEV_ATTR_WDIV(S_IWUSR | S_IRUGO,
 		ade7754_read_8bit,
 		ade7754_write_8bit,
 		ADE7754_WDIV);
 static IIO_DEV_ATTR_VADIV(S_IWUSR | S_IRUGO,
 		ade7754_read_8bit,
 		ade7754_write_8bit,
 		ADE7754_VADIV);
 static IIO_DEV_ATTR_CFNUM(S_IWUSR | S_IRUGO,
 		ade7754_read_16bit,
 		ade7754_write_16bit,
 		ADE7754_CFNUM);
 static IIO_DEV_ATTR_CFDEN(S_IWUSR | S_IRUGO,
 		ade7754_read_16bit,
 		ade7754_write_16bit,
 		ADE7754_CFDEN);
 static IIO_DEV_ATTR_ACTIVE_POWER_A_GAIN(S_IWUSR | S_IRUGO,
 		ade7754_read_16bit,
 		ade7754_write_16bit,
 		ADE7754_AAPGAIN);
 static IIO_DEV_ATTR_ACTIVE_POWER_B_GAIN(S_IWUSR | S_IRUGO,
 		ade7754_read_16bit,
 		ade7754_write_16bit,
 		ADE7754_BAPGAIN);
 static IIO_DEV_ATTR_ACTIVE_POWER_C_GAIN(S_IWUSR | S_IRUGO,
 		ade7754_read_16bit,
 		ade7754_write_16bit,
 		ADE7754_CAPGAIN);
 static IIO_DEV_ATTR_AIRMS(S_IRUGO,
 		ade7754_read_24bit,
 		NULL,
 		ADE7754_AIRMS);
 static IIO_DEV_ATTR_BIRMS(S_IRUGO,
 		ade7754_read_24bit,
 		NULL,
 		ADE7754_BIRMS);
 static IIO_DEV_ATTR_CIRMS(S_IRUGO,
 		ade7754_read_24bit,
 		NULL,
 		ADE7754_CIRMS);
 static IIO_DEV_ATTR_AVRMS(S_IRUGO,
 		ade7754_read_24bit,
 		NULL,
 		ADE7754_AVRMS);
 static IIO_DEV_ATTR_BVRMS(S_IRUGO,
 		ade7754_read_24bit,
 		NULL,
 		ADE7754_BVRMS);
 static IIO_DEV_ATTR_CVRMS(S_IRUGO,
 		ade7754_read_24bit,
 		NULL,
 		ADE7754_CVRMS);
 static IIO_DEV_ATTR_AIRMSOS(S_IRUGO,
 		ade7754_read_16bit,
 		ade7754_write_16bit,
 		ADE7754_AIRMSOS);
 static IIO_DEV_ATTR_BIRMSOS(S_IRUGO,
 		ade7754_read_16bit,
 		ade7754_write_16bit,
 		ADE7754_BIRMSOS);
 static IIO_DEV_ATTR_CIRMSOS(S_IRUGO,
 		ade7754_read_16bit,
 		ade7754_write_16bit,
 		ADE7754_CIRMSOS);
 static IIO_DEV_ATTR_AVRMSOS(S_IRUGO,
 		ade7754_read_16bit,
 		ade7754_write_16bit,
 		ADE7754_AVRMSOS);
 static IIO_DEV_ATTR_BVRMSOS(S_IRUGO,
 		ade7754_read_16bit,
 		ade7754_write_16bit,
 		ADE7754_BVRMSOS);
 static IIO_DEV_ATTR_CVRMSOS(S_IRUGO,
 		ade7754_read_16bit,
 		ade7754_write_16bit,
 		ADE7754_CVRMSOS);

 static int ade7754_set_irq(struct device *dev, bool enable)
 {
 	int ret;
 	u16 irqen;

 	ret = ade7754_spi_read_reg_16(dev, ADE7754_IRQEN, &irqen);
 	if (ret)
 		return ret;

 	if (enable)
 		irqen |= BIT(14); /* Enables an interrupt when a data is
 				   * present in the waveform register
 				   */
 	else
 		irqen &= ~BIT(14);

 	ret = ade7754_spi_write_reg_16(dev, ADE7754_IRQEN, irqen);

 	return ret;
 }

 /* Power down the device */
 static int ade7754_stop_device(struct device *dev)
 {
 	int ret;
 	u8 val;

 	ret = ade7754_spi_read_reg_8(dev, ADE7754_OPMODE, &val);
 	if (ret < 0) {
 		dev_err(dev, "unable to power down the device, error: %d",
 			ret);
 		return ret;
 	}

 	val |= 7 << 3;  /* ADE7754 powered down */
 	return ade7754_spi_write_reg_8(dev, ADE7754_OPMODE, val);
 }

 static int ade7754_initial_setup(struct iio_dev *indio_dev)
 {
 	int ret;
 	struct ade7754_state *st = iio_priv(indio_dev);
 	struct device *dev = &indio_dev->dev;

 	/* use low spi speed for init */
 	st->us->mode = SPI_MODE_3;
 	spi_setup(st->us);

 	/* Disable IRQ */
 	ret = ade7754_set_irq(dev, false);
 	if (ret) {
 		dev_err(dev, "disable irq failed");
 		goto err_ret;
 	}

 	ade7754_reset(dev);
 	msleep(ADE7754_STARTUP_DELAY);

 err_ret:
 	return ret;
 }

 static ssize_t ade7754_read_frequency(struct device *dev,
 				      struct device_attribute *attr,
 				      char *buf)
 {
 	int ret;
 	u8 t;
 	int sps;

 	ret = ade7754_spi_read_reg_8(dev, ADE7754_WAVMODE, &t);
 	if (ret)
 		return ret;

 	t = (t >> 3) & 0x3;
 	sps = 26000 / (1 + t);

 	return sprintf(buf, "%d\n", sps);
 }

 static ssize_t ade7754_write_frequency(struct device *dev,
 				       struct device_attribute *attr,
 				       const char *buf,
 				       size_t len)
 {
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct ade7754_state *st = iio_priv(indio_dev);
 	u16 val;
 	int ret;
 	u8 reg, t;

 	ret = kstrtou16(buf, 10, &val);
 	if (ret)
 		return ret;
 	if (!val)
 		return -EINVAL;

 	mutex_lock(&indio_dev->mlock);

 	t = 26000 / val;
 	if (t > 0)
 		t--;

 	if (t > 1)
 		st->us->max_speed_hz = ADE7754_SPI_SLOW;
 	else
 		st->us->max_speed_hz = ADE7754_SPI_FAST;

 	ret = ade7754_spi_read_reg_8(dev, ADE7754_WAVMODE, &reg);
 	if (ret)
 		goto out;

 	reg &= ~(3 << 3);
 	reg |= t << 3;

 	ret = ade7754_spi_write_reg_8(dev, ADE7754_WAVMODE, reg);

 out:
 	mutex_unlock(&indio_dev->mlock);

 	return ret ? ret : len;
 }
 static IIO_DEV_ATTR_TEMP_RAW(ade7754_read_8bit);
 static IIO_CONST_ATTR(in_temp_offset, "129 C");
 static IIO_CONST_ATTR(in_temp_scale, "4 C");

 static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
 		ade7754_read_frequency,
 		ade7754_write_frequency);

 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("26000 13000 65000 33000");

 static struct attribute *ade7754_attributes[] = {
 	&iio_dev_attr_in_temp_raw.dev_attr.attr,
 	&iio_const_attr_in_temp_offset.dev_attr.attr,
 	&iio_const_attr_in_temp_scale.dev_attr.attr,
 	&iio_dev_attr_sampling_frequency.dev_attr.attr,
 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
 	&iio_dev_attr_aenergy.dev_attr.attr,
 	&iio_dev_attr_laenergy.dev_attr.attr,
 	&iio_dev_attr_vaenergy.dev_attr.attr,
 	&iio_dev_attr_lvaenergy.dev_attr.attr,
 	&iio_dev_attr_vpeak.dev_attr.attr,
 	&iio_dev_attr_ipeak.dev_attr.attr,
 	&iio_dev_attr_aphcal.dev_attr.attr,
 	&iio_dev_attr_bphcal.dev_attr.attr,
 	&iio_dev_attr_cphcal.dev_attr.attr,
 	&iio_dev_attr_aapos.dev_attr.attr,
 	&iio_dev_attr_bapos.dev_attr.attr,
 	&iio_dev_attr_capos.dev_attr.attr,
 	&iio_dev_attr_wdiv.dev_attr.attr,
 	&iio_dev_attr_vadiv.dev_attr.attr,
 	&iio_dev_attr_cfnum.dev_attr.attr,
 	&iio_dev_attr_cfden.dev_attr.attr,
 	&iio_dev_attr_active_power_a_gain.dev_attr.attr,
 	&iio_dev_attr_active_power_b_gain.dev_attr.attr,
 	&iio_dev_attr_active_power_c_gain.dev_attr.attr,
 	&iio_dev_attr_airms.dev_attr.attr,
 	&iio_dev_attr_birms.dev_attr.attr,
 	&iio_dev_attr_cirms.dev_attr.attr,
 	&iio_dev_attr_avrms.dev_attr.attr,
 	&iio_dev_attr_bvrms.dev_attr.attr,
 	&iio_dev_attr_cvrms.dev_attr.attr,
 	&iio_dev_attr_airmsos.dev_attr.attr,
 	&iio_dev_attr_birmsos.dev_attr.attr,
 	&iio_dev_attr_cirmsos.dev_attr.attr,
 	&iio_dev_attr_avrmsos.dev_attr.attr,
 	&iio_dev_attr_bvrmsos.dev_attr.attr,
 	&iio_dev_attr_cvrmsos.dev_attr.attr,
 	NULL,
 };

 static const struct attribute_group ade7754_attribute_group = {
 	.attrs = ade7754_attributes,
 };

 static const struct iio_info ade7754_info = {
 	.attrs = &ade7754_attribute_group,
 	.driver_module = THIS_MODULE,
 };

 static int ade7754_probe(struct spi_device *spi)
 {
 	int ret;
 	struct ade7754_state *st;
 	struct iio_dev *indio_dev;

 	/* setup the industrialio driver allocated elements */
 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
 	if (!indio_dev)
 		return -ENOMEM;
 	/* this is only used for removal purposes */
 	spi_set_drvdata(spi, indio_dev);

 	st = iio_priv(indio_dev);
 	st->us = spi;
 	mutex_init(&st->buf_lock);

 	indio_dev->name = spi->dev.driver->name;
 	indio_dev->dev.parent = &spi->dev;
 	indio_dev->info = &ade7754_info;
 	indio_dev->modes = INDIO_DIRECT_MODE;

 	/* Get the device into a sane initial state */
 	ret = ade7754_initial_setup(indio_dev);
 	if (ret)
 		goto powerdown_on_error;
 	ret = iio_device_register(indio_dev);
 	if (ret)
 		goto powerdown_on_error;
 	return ret;

 powerdown_on_error:
 	ade7754_stop_device(&indio_dev->dev);
 	return ret;
 }

 static int ade7754_remove(struct spi_device *spi)
 {
 	struct iio_dev *indio_dev = spi_get_drvdata(spi);

 	iio_device_unregister(indio_dev);
 	ade7754_stop_device(&indio_dev->dev);

 	return 0;
 }

 static struct spi_driver ade7754_driver = {
 	.driver = {
 		.name = "ade7754",
 	},
 	.probe = ade7754_probe,
 	.remove = ade7754_remove,
 };
 module_spi_driver(ade7754_driver);

 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
 MODULE_DESCRIPTION("Analog Devices ADE7754 Polyphase Multifunction Energy Metering IC Driver");
 MODULE_LICENSE("GPL v2");
 MODULE_ALIAS("spi:ad7754");
	/*
	* ADE7754 Polyphase Multifunction Energy Metering IC Driver
	*
	* Copyright 2010 Analog Devices Inc.
	*
	* Licensed under the GPL-2 or later.
	*/

	#include <linux/interrupt.h>
	#include <linux/irq.h>
	#include <linux/delay.h>
	#include <linux/mutex.h>
	#include <linux/device.h>
	#include <linux/kernel.h>
	#include <linux/spi/spi.h>
	#include <linux/slab.h>
	#include <linux/sysfs.h>
	#include <linux/list.h>
	#include <linux/module.h>

	#include <linux/iio/iio.h>
	#include <linux/iio/sysfs.h>
	#include "meter.h"
	#include "ade7754.h"

	static int ade7754_spi_write_reg_8(struct device *dev, u8 reg_address, u8 val)
	{
	int ret;
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct ade7754_state *st = iio_priv(indio_dev);

	mutex_lock(&st->buf_lock);
	st->tx[0] = ADE7754_WRITE_REG(reg_address);
	st->tx[1] = val;

	ret = spi_write(st->us, st->tx, 2);
	mutex_unlock(&st->buf_lock);

	return ret;
	}

	static int ade7754_spi_write_reg_16(struct device *dev,
	u8 reg_address, u16 value)
	{
	int ret;
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct ade7754_state *st = iio_priv(indio_dev);

	mutex_lock(&st->buf_lock);
	st->tx[0] = ADE7754_WRITE_REG(reg_address);
	st->tx[1] = (value >> 8) & 0xFF;
	st->tx[2] = value & 0xFF;
	ret = spi_write(st->us, st->tx, 3);
	mutex_unlock(&st->buf_lock);

	return ret;
	}

	static int ade7754_spi_read_reg_8(struct device dev, u8 reg_address, u8 val)
	{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct ade7754_state *st = iio_priv(indio_dev);
	int ret;

	ret = spi_w8r8(st->us, ADE7754_READ_REG(reg_address));
	if (ret < 0) {
	dev_err(&st->us->dev, "problem when reading 8 bit register 0x%02X",
	reg_address);
	return ret;
	}
	*val = ret;

	return 0;
	}

	static int ade7754_spi_read_reg_16(struct device *dev,
	u8 reg_address, u16 *val)
	{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct ade7754_state *st = iio_priv(indio_dev);
	int ret;

	ret = spi_w8r16be(st->us, ADE7754_READ_REG(reg_address));
	if (ret < 0) {
	dev_err(&st->us->dev, "problem when reading 16 bit register 0x%02X",
	reg_address);
	return ret;
	}

	*val = ret;

	return 0;
	}

	static int ade7754_spi_read_reg_24(struct device *dev,
	u8 reg_address, u32 *val)
	{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct ade7754_state *st = iio_priv(indio_dev);
	int ret;
	struct spi_transfer xfers[] = {
	{
	.tx_buf = st->tx,
	.rx_buf = st->rx,
	.bits_per_word = 8,
	.len = 4,
	},
	};

	mutex_lock(&st->buf_lock);
	st->tx[0] = ADE7754_READ_REG(reg_address);
	st->tx[1] = 0;
	st->tx[2] = 0;
	st->tx[3] = 0;

	ret = spi_sync_transfer(st->us, xfers, ARRAY_SIZE(xfers));
	if (ret) {
	dev_err(&st->us->dev, "problem when reading 24 bit register 0x%02X",
	reg_address);
	goto error_ret;
	}
	*val = (st->rx[1] << 16) \| (st->rx[2] << 8) \| st->rx[3];

	error_ret:
	mutex_unlock(&st->buf_lock);
	return ret;
	}

	static ssize_t ade7754_read_8bit(struct device *dev,
	struct device_attribute *attr,
	char *buf)
	{
	int ret;
	u8 val = 0;
	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);

	ret = ade7754_spi_read_reg_8(dev, this_attr->address, &val);
	if (ret)
	return ret;

	return sprintf(buf, "%u\n", val);
	}

	static ssize_t ade7754_read_16bit(struct device *dev,
	struct device_attribute *attr,
	char *buf)
	{
	int ret;
	u16 val = 0;
	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);

	ret = ade7754_spi_read_reg_16(dev, this_attr->address, &val);
	if (ret)
	return ret;

	return sprintf(buf, "%u\n", val);
	}

	static ssize_t ade7754_read_24bit(struct device *dev,
	struct device_attribute *attr,
	char *buf)
	{
	int ret;
	u32 val = 0;
	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);

	ret = ade7754_spi_read_reg_24(dev, this_attr->address, &val);
	if (ret)
	return ret;

	return sprintf(buf, "%u\n", val & 0xFFFFFF);
	}

	static ssize_t ade7754_write_8bit(struct device *dev,
	struct device_attribute *attr,
	const char *buf,
	size_t len)
	{
	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
	int ret;
	u8 val;

	ret = kstrtou8(buf, 10, &val);
	if (ret)
	goto error_ret;
	ret = ade7754_spi_write_reg_8(dev, this_attr->address, val);

	error_ret:
	return ret ? ret : len;
	}

	static ssize_t ade7754_write_16bit(struct device *dev,
	struct device_attribute *attr,
	const char *buf,
	size_t len)
	{
	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
	int ret;
	u16 val;

	ret = kstrtou16(buf, 10, &val);
	if (ret)
	goto error_ret;
	ret = ade7754_spi_write_reg_16(dev, this_attr->address, val);

	error_ret:
	return ret ? ret : len;
	}

	static int ade7754_reset(struct device *dev)
	{
	int ret;
	u8 val;

	ret = ade7754_spi_read_reg_8(dev, ADE7754_OPMODE, &val);
	if (ret < 0)
	return ret;

	val \|= BIT(6); /* Software Chip Reset */
	return ade7754_spi_write_reg_8(dev, ADE7754_OPMODE, val);
	}

	static IIO_DEV_ATTR_AENERGY(ade7754_read_24bit, ADE7754_AENERGY);
	static IIO_DEV_ATTR_LAENERGY(ade7754_read_24bit, ADE7754_LAENERGY);
	static IIO_DEV_ATTR_VAENERGY(ade7754_read_24bit, ADE7754_VAENERGY);
	static IIO_DEV_ATTR_LVAENERGY(ade7754_read_24bit, ADE7754_LVAENERGY);
	static IIO_DEV_ATTR_VPEAK(S_IWUSR \| S_IRUGO,
	ade7754_read_8bit,
	ade7754_write_8bit,
	ADE7754_VPEAK);
	static IIO_DEV_ATTR_IPEAK(S_IWUSR \| S_IRUGO,
	ade7754_read_8bit,
	ade7754_write_8bit,
	ADE7754_VPEAK);
	static IIO_DEV_ATTR_APHCAL(S_IWUSR \| S_IRUGO,
	ade7754_read_8bit,
	ade7754_write_8bit,
	ADE7754_APHCAL);
	static IIO_DEV_ATTR_BPHCAL(S_IWUSR \| S_IRUGO,
	ade7754_read_8bit,
	ade7754_write_8bit,
	ADE7754_BPHCAL);
	static IIO_DEV_ATTR_CPHCAL(S_IWUSR \| S_IRUGO,
	ade7754_read_8bit,
	ade7754_write_8bit,
	ADE7754_CPHCAL);
	static IIO_DEV_ATTR_AAPOS(S_IWUSR \| S_IRUGO,
	ade7754_read_16bit,
	ade7754_write_16bit,
	ADE7754_AAPOS);
	static IIO_DEV_ATTR_BAPOS(S_IWUSR \| S_IRUGO,
	ade7754_read_16bit,
	ade7754_write_16bit,
	ADE7754_BAPOS);
	static IIO_DEV_ATTR_CAPOS(S_IWUSR \| S_IRUGO,
	ade7754_read_16bit,
	ade7754_write_16bit,
	ADE7754_CAPOS);
	static IIO_DEV_ATTR_WDIV(S_IWUSR \| S_IRUGO,
	ade7754_read_8bit,
	ade7754_write_8bit,
	ADE7754_WDIV);
	static IIO_DEV_ATTR_VADIV(S_IWUSR \| S_IRUGO,
	ade7754_read_8bit,
	ade7754_write_8bit,
	ADE7754_VADIV);
	static IIO_DEV_ATTR_CFNUM(S_IWUSR \| S_IRUGO,
	ade7754_read_16bit,
	ade7754_write_16bit,
	ADE7754_CFNUM);
	static IIO_DEV_ATTR_CFDEN(S_IWUSR \| S_IRUGO,
	ade7754_read_16bit,
	ade7754_write_16bit,
	ADE7754_CFDEN);
	static IIO_DEV_ATTR_ACTIVE_POWER_A_GAIN(S_IWUSR \| S_IRUGO,
	ade7754_read_16bit,
	ade7754_write_16bit,
	ADE7754_AAPGAIN);
	static IIO_DEV_ATTR_ACTIVE_POWER_B_GAIN(S_IWUSR \| S_IRUGO,
	ade7754_read_16bit,
	ade7754_write_16bit,
	ADE7754_BAPGAIN);
	static IIO_DEV_ATTR_ACTIVE_POWER_C_GAIN(S_IWUSR \| S_IRUGO,
	ade7754_read_16bit,
	ade7754_write_16bit,
	ADE7754_CAPGAIN);
	static IIO_DEV_ATTR_AIRMS(S_IRUGO,
	ade7754_read_24bit,
	NULL,
	ADE7754_AIRMS);
	static IIO_DEV_ATTR_BIRMS(S_IRUGO,
	ade7754_read_24bit,
	NULL,
	ADE7754_BIRMS);
	static IIO_DEV_ATTR_CIRMS(S_IRUGO,
	ade7754_read_24bit,
	NULL,
	ADE7754_CIRMS);
	static IIO_DEV_ATTR_AVRMS(S_IRUGO,
	ade7754_read_24bit,
	NULL,
	ADE7754_AVRMS);
	static IIO_DEV_ATTR_BVRMS(S_IRUGO,
	ade7754_read_24bit,
	NULL,
	ADE7754_BVRMS);
	static IIO_DEV_ATTR_CVRMS(S_IRUGO,
	ade7754_read_24bit,
	NULL,
	ADE7754_CVRMS);
	static IIO_DEV_ATTR_AIRMSOS(S_IRUGO,
	ade7754_read_16bit,
	ade7754_write_16bit,
	ADE7754_AIRMSOS);
	static IIO_DEV_ATTR_BIRMSOS(S_IRUGO,
	ade7754_read_16bit,
	ade7754_write_16bit,
	ADE7754_BIRMSOS);
	static IIO_DEV_ATTR_CIRMSOS(S_IRUGO,
	ade7754_read_16bit,
	ade7754_write_16bit,
	ADE7754_CIRMSOS);
	static IIO_DEV_ATTR_AVRMSOS(S_IRUGO,
	ade7754_read_16bit,
	ade7754_write_16bit,
	ADE7754_AVRMSOS);
	static IIO_DEV_ATTR_BVRMSOS(S_IRUGO,
	ade7754_read_16bit,
	ade7754_write_16bit,
	ADE7754_BVRMSOS);
	static IIO_DEV_ATTR_CVRMSOS(S_IRUGO,
	ade7754_read_16bit,
	ade7754_write_16bit,
	ADE7754_CVRMSOS);

	static int ade7754_set_irq(struct device *dev, bool enable)
	{
	int ret;
	u16 irqen;

	ret = ade7754_spi_read_reg_16(dev, ADE7754_IRQEN, &irqen);
	if (ret)
	return ret;

	if (enable)
	irqen \|= BIT(14); /* Enables an interrupt when a data is
	* present in the waveform register
	*/
	else
	irqen &= ~BIT(14);

	ret = ade7754_spi_write_reg_16(dev, ADE7754_IRQEN, irqen);

	return ret;
	}

	/* Power down the device */
	static int ade7754_stop_device(struct device *dev)
	{
	int ret;
	u8 val;

	ret = ade7754_spi_read_reg_8(dev, ADE7754_OPMODE, &val);
	if (ret < 0) {
	dev_err(dev, "unable to power down the device, error: %d",
	ret);
	return ret;
	}

	val \|= 7 << 3; /* ADE7754 powered down */
	return ade7754_spi_write_reg_8(dev, ADE7754_OPMODE, val);
	}

	static int ade7754_initial_setup(struct iio_dev *indio_dev)
	{
	int ret;
	struct ade7754_state *st = iio_priv(indio_dev);
	struct device *dev = &indio_dev->dev;

	/* use low spi speed for init */
	st->us->mode = SPI_MODE_3;
	spi_setup(st->us);

	/* Disable IRQ */
	ret = ade7754_set_irq(dev, false);
	if (ret) {
	dev_err(dev, "disable irq failed");
	goto err_ret;
	}

	ade7754_reset(dev);
	msleep(ADE7754_STARTUP_DELAY);

	err_ret:
	return ret;
	}

	static ssize_t ade7754_read_frequency(struct device *dev,
	struct device_attribute *attr,
	char *buf)
	{
	int ret;
	u8 t;
	int sps;

	ret = ade7754_spi_read_reg_8(dev, ADE7754_WAVMODE, &t);
	if (ret)
	return ret;

	t = (t >> 3) & 0x3;
	sps = 26000 / (1 + t);

	return sprintf(buf, "%d\n", sps);
	}

	static ssize_t ade7754_write_frequency(struct device *dev,
	struct device_attribute *attr,
	const char *buf,
	size_t len)
	{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct ade7754_state *st = iio_priv(indio_dev);
	u16 val;
	int ret;
	u8 reg, t;

	ret = kstrtou16(buf, 10, &val);
	if (ret)
	return ret;
	if (!val)
	return -EINVAL;

	mutex_lock(&indio_dev->mlock);

	t = 26000 / val;
	if (t > 0)
	t--;

	if (t > 1)
	st->us->max_speed_hz = ADE7754_SPI_SLOW;
	else
	st->us->max_speed_hz = ADE7754_SPI_FAST;

	ret = ade7754_spi_read_reg_8(dev, ADE7754_WAVMODE, &reg);
	if (ret)
	goto out;

	reg &= ~(3 << 3);
	reg \|= t << 3;

	ret = ade7754_spi_write_reg_8(dev, ADE7754_WAVMODE, reg);

	out:
	mutex_unlock(&indio_dev->mlock);

	return ret ? ret : len;
	}
	static IIO_DEV_ATTR_TEMP_RAW(ade7754_read_8bit);
	static IIO_CONST_ATTR(in_temp_offset, "129 C");
	static IIO_CONST_ATTR(in_temp_scale, "4 C");

	static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR \| S_IRUGO,
	ade7754_read_frequency,
	ade7754_write_frequency);

	static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("26000 13000 65000 33000");

	static struct attribute *ade7754_attributes[] = {
	&iio_dev_attr_in_temp_raw.dev_attr.attr,
	&iio_const_attr_in_temp_offset.dev_attr.attr,
	&iio_const_attr_in_temp_scale.dev_attr.attr,
	&iio_dev_attr_sampling_frequency.dev_attr.attr,
	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
	&iio_dev_attr_aenergy.dev_attr.attr,
	&iio_dev_attr_laenergy.dev_attr.attr,
	&iio_dev_attr_vaenergy.dev_attr.attr,
	&iio_dev_attr_lvaenergy.dev_attr.attr,
	&iio_dev_attr_vpeak.dev_attr.attr,
	&iio_dev_attr_ipeak.dev_attr.attr,
	&iio_dev_attr_aphcal.dev_attr.attr,
	&iio_dev_attr_bphcal.dev_attr.attr,
	&iio_dev_attr_cphcal.dev_attr.attr,
	&iio_dev_attr_aapos.dev_attr.attr,
	&iio_dev_attr_bapos.dev_attr.attr,
	&iio_dev_attr_capos.dev_attr.attr,
	&iio_dev_attr_wdiv.dev_attr.attr,
	&iio_dev_attr_vadiv.dev_attr.attr,
	&iio_dev_attr_cfnum.dev_attr.attr,
	&iio_dev_attr_cfden.dev_attr.attr,
	&iio_dev_attr_active_power_a_gain.dev_attr.attr,
	&iio_dev_attr_active_power_b_gain.dev_attr.attr,
	&iio_dev_attr_active_power_c_gain.dev_attr.attr,
	&iio_dev_attr_airms.dev_attr.attr,
	&iio_dev_attr_birms.dev_attr.attr,
	&iio_dev_attr_cirms.dev_attr.attr,
	&iio_dev_attr_avrms.dev_attr.attr,
	&iio_dev_attr_bvrms.dev_attr.attr,
	&iio_dev_attr_cvrms.dev_attr.attr,
	&iio_dev_attr_airmsos.dev_attr.attr,
	&iio_dev_attr_birmsos.dev_attr.attr,
	&iio_dev_attr_cirmsos.dev_attr.attr,
	&iio_dev_attr_avrmsos.dev_attr.attr,
	&iio_dev_attr_bvrmsos.dev_attr.attr,
	&iio_dev_attr_cvrmsos.dev_attr.attr,
	NULL,
	};

	static const struct attribute_group ade7754_attribute_group = {
	.attrs = ade7754_attributes,
	};

	static const struct iio_info ade7754_info = {
	.attrs = &ade7754_attribute_group,
	.driver_module = THIS_MODULE,
	};

	static int ade7754_probe(struct spi_device *spi)
	{
	int ret;
	struct ade7754_state *st;
	struct iio_dev *indio_dev;

	/* setup the industrialio driver allocated elements */
	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
	if (!indio_dev)
	return -ENOMEM;
	/* this is only used for removal purposes */
	spi_set_drvdata(spi, indio_dev);

	st = iio_priv(indio_dev);
	st->us = spi;
	mutex_init(&st->buf_lock);

	indio_dev->name = spi->dev.driver->name;
	indio_dev->dev.parent = &spi->dev;
	indio_dev->info = &ade7754_info;
	indio_dev->modes = INDIO_DIRECT_MODE;

	/* Get the device into a sane initial state */
	ret = ade7754_initial_setup(indio_dev);
	if (ret)
	goto powerdown_on_error;
	ret = iio_device_register(indio_dev);
	if (ret)
	goto powerdown_on_error;
	return ret;

	powerdown_on_error:
	ade7754_stop_device(&indio_dev->dev);
	return ret;
	}

	static int ade7754_remove(struct spi_device *spi)
	{
	struct iio_dev *indio_dev = spi_get_drvdata(spi);

	iio_device_unregister(indio_dev);
	ade7754_stop_device(&indio_dev->dev);

	return 0;
	}

	static struct spi_driver ade7754_driver = {
	.driver = {
	.name = "ade7754",
	},
	.probe = ade7754_probe,
	.remove = ade7754_remove,
	};
	module_spi_driver(ade7754_driver);

	MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
	MODULE_DESCRIPTION("Analog Devices ADE7754 Polyphase Multifunction Energy Metering IC Driver");
	MODULE_LICENSE("GPL v2");
	MODULE_ALIAS("spi:ad7754");