iio: accel: Add support for Freescale MMA7660FC (32133be6) · Commits · e / devices / android_kernel_fairphone_FP3

drivers/iio/accel/Kconfig

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		@@ -136,6 +136,16 @@ config MMA7455_SPI
		To compile this driver as a module, choose M here: the module
		will be called mma7455_spi.

		config MMA7660
		tristate "Freescale MMA7660FC 3-Axis Accelerometer Driver"
		depends on I2C
		help
		Say yes here to get support for the Freescale MMA7660FC 3-Axis
		accelerometer.

		Choosing M will build the driver as a module. If so, the module
		will be called mma7660.

		config MMA8452
		tristate "Freescale MMA8452Q and similar Accelerometers Driver"
		depends on I2C

drivers/iio/accel/Makefile

+2 −0

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		@@ -15,6 +15,8 @@ obj-$(CONFIG_MMA7455) += mma7455_core.o
		obj-$(CONFIG_MMA7455_I2C) += mma7455_i2c.o
		obj-$(CONFIG_MMA7455_SPI) += mma7455_spi.o

		obj-$(CONFIG_MMA7660) += mma7660.o

		obj-$(CONFIG_MMA8452) += mma8452.o

		obj-$(CONFIG_MMA9551_CORE) += mma9551_core.o

drivers/iio/accel/mma7660.c

0 → 100644

+277 −0

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		/**
		* Freescale MMA7660FC 3-Axis Accelerometer
		*
		* Copyright (c) 2016, Intel Corporation.
		*
		* This file is subject to the terms and conditions of version 2 of
		* the GNU General Public License. See the file COPYING in the main
		* directory of this archive for more details.
		*
		* IIO driver for Freescale MMA7660FC; 7-bit I2C address: 0x4c.
		*/

		#include <linux/acpi.h>
		#include <linux/i2c.h>
		#include <linux/module.h>
		#include <linux/iio/iio.h>
		#include <linux/iio/sysfs.h>

		#define MMA7660_DRIVER_NAME "mma7660"

		#define MMA7660_REG_XOUT 0x00
		#define MMA7660_REG_YOUT 0x01
		#define MMA7660_REG_ZOUT 0x02
		#define MMA7660_REG_OUT_BIT_ALERT BIT(6)

		#define MMA7660_REG_MODE 0x07
		#define MMA7660_REG_MODE_BIT_MODE BIT(0)
		#define MMA7660_REG_MODE_BIT_TON BIT(2)

		#define MMA7660_I2C_READ_RETRIES 5

		/*
		* The accelerometer has one measurement range:
		*
		* -1.5g - +1.5g (6-bit, signed)
		*
		* scale = (1.5 + 1.5) * 9.81 / (2^6 - 1) = 0.467142857
		*/

		#define MMA7660_SCALE_AVAIL "0.467142857"

		const int mma7660_nscale = 467142857;

		#define MMA7660_CHANNEL(reg, axis) { \
		.type = IIO_ACCEL, \
		.address = reg, \
		.modified = 1, \
		.channel2 = IIO_MOD_##axis, \
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
		}

		static const struct iio_chan_spec mma7660_channels[] = {
		MMA7660_CHANNEL(MMA7660_REG_XOUT, X),
		MMA7660_CHANNEL(MMA7660_REG_YOUT, Y),
		MMA7660_CHANNEL(MMA7660_REG_ZOUT, Z),
		};

		enum mma7660_mode {
		MMA7660_MODE_STANDBY,
		MMA7660_MODE_ACTIVE
		};

		struct mma7660_data {
		struct i2c_client *client;
		struct mutex lock;
		enum mma7660_mode mode;
		};

		static IIO_CONST_ATTR(in_accel_scale_available, MMA7660_SCALE_AVAIL);

		static struct attribute *mma7660_attributes[] = {
		&iio_const_attr_in_accel_scale_available.dev_attr.attr,
		NULL,
		};

		static const struct attribute_group mma7660_attribute_group = {
		.attrs = mma7660_attributes
		};

		static int mma7660_set_mode(struct mma7660_data *data,
		enum mma7660_mode mode)
		{
		int ret;
		struct i2c_client *client = data->client;

		if (mode == data->mode)
		return 0;

		ret = i2c_smbus_read_byte_data(client, MMA7660_REG_MODE);
		if (ret < 0) {
		dev_err(&client->dev, "failed to read sensor mode\n");
		return ret;
		}

		if (mode == MMA7660_MODE_ACTIVE) {
		ret &= ~MMA7660_REG_MODE_BIT_TON;
		ret \|= MMA7660_REG_MODE_BIT_MODE;
		} else {
		ret &= ~MMA7660_REG_MODE_BIT_TON;
		ret &= ~MMA7660_REG_MODE_BIT_MODE;
		}

		ret = i2c_smbus_write_byte_data(client, MMA7660_REG_MODE, ret);
		if (ret < 0) {
		dev_err(&client->dev, "failed to change sensor mode\n");
		return ret;
		}

		data->mode = mode;

		return ret;
		}

		static int mma7660_read_accel(struct mma7660_data *data, u8 address)
		{
		int ret, retries = MMA7660_I2C_READ_RETRIES;
		struct i2c_client *client = data->client;

		/*
		* Read data. If the Alert bit is set, the register was read at
		* the same time as the device was attempting to update the content.
		* The solution is to read the register again. Do this only
		* MMA7660_I2C_READ_RETRIES times to avoid spending too much time
		* in the kernel.
		*/
		do {
		ret = i2c_smbus_read_byte_data(client, address);
		if (ret < 0) {
		dev_err(&client->dev, "register read failed\n");
		return ret;
		}
		} while (retries-- > 0 && ret & MMA7660_REG_OUT_BIT_ALERT);

		if (ret & MMA7660_REG_OUT_BIT_ALERT) {
		dev_err(&client->dev, "all register read retries failed\n");
		return -ETIMEDOUT;
		}

		return ret;
		}

		static int mma7660_read_raw(struct iio_dev *indio_dev,
		struct iio_chan_spec const *chan,
		int val, int val2, long mask)
		{
		struct mma7660_data *data = iio_priv(indio_dev);
		int ret;

		switch (mask) {
		case IIO_CHAN_INFO_RAW:
		mutex_lock(&data->lock);
		ret = mma7660_read_accel(data, chan->address);
		mutex_unlock(&data->lock);
		if (ret < 0)
		return ret;
		*val = sign_extend32(ret, 5);
		return IIO_VAL_INT;
		case IIO_CHAN_INFO_SCALE:
		*val = 0;
		*val2 = mma7660_nscale;
		return IIO_VAL_INT_PLUS_NANO;
		default:
		return -EINVAL;
		}

		return -EINVAL;
		}

		static const struct iio_info mma7660_info = {
		.driver_module = THIS_MODULE,
		.read_raw = mma7660_read_raw,
		.attrs = &mma7660_attribute_group,
		};

		static int mma7660_probe(struct i2c_client *client,
		const struct i2c_device_id *id)
		{
		int ret;
		struct iio_dev *indio_dev;
		struct mma7660_data *data;

		indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
		if (!indio_dev) {
		dev_err(&client->dev, "iio allocation failed!\n");
		return -ENOMEM;
		}

		data = iio_priv(indio_dev);
		data->client = client;
		i2c_set_clientdata(client, indio_dev);
		mutex_init(&data->lock);
		data->mode = MMA7660_MODE_STANDBY;

		indio_dev->dev.parent = &client->dev;
		indio_dev->info = &mma7660_info;
		indio_dev->name = MMA7660_DRIVER_NAME;
		indio_dev->modes = INDIO_DIRECT_MODE;
		indio_dev->channels = mma7660_channels;
		indio_dev->num_channels = ARRAY_SIZE(mma7660_channels);

		ret = mma7660_set_mode(data, MMA7660_MODE_ACTIVE);
		if (ret < 0)
		return ret;

		ret = iio_device_register(indio_dev);
		if (ret < 0) {
		dev_err(&client->dev, "device_register failed\n");
		mma7660_set_mode(data, MMA7660_MODE_STANDBY);
		}

		return ret;
		}

		static int mma7660_remove(struct i2c_client *client)
		{
		struct iio_dev *indio_dev = i2c_get_clientdata(client);

		iio_device_unregister(indio_dev);

		return mma7660_set_mode(iio_priv(indio_dev), MMA7660_MODE_STANDBY);
		}

		#ifdef CONFIG_PM_SLEEP
		static int mma7660_suspend(struct device *dev)
		{
		struct mma7660_data *data;

		data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));

		return mma7660_set_mode(data, MMA7660_MODE_STANDBY);
		}

		static int mma7660_resume(struct device *dev)
		{
		struct mma7660_data *data;

		data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));

		return mma7660_set_mode(data, MMA7660_MODE_ACTIVE);
		}

		static SIMPLE_DEV_PM_OPS(mma7660_pm_ops, mma7660_suspend, mma7660_resume);

		#define MMA7660_PM_OPS (&mma7660_pm_ops)
		#else
		#define MMA7660_PM_OPS NULL
		#endif

		static const struct i2c_device_id mma7660_i2c_id[] = {
		{"mma7660", 0},
		{}
		};

		static const struct acpi_device_id mma7660_acpi_id[] = {
		{"MMA7660", 0},
		{}
		};

		MODULE_DEVICE_TABLE(acpi, mma7660_acpi_id);

		static struct i2c_driver mma7660_driver = {
		.driver = {
		.name = "mma7660",
		.pm = MMA7660_PM_OPS,
		.acpi_match_table = ACPI_PTR(mma7660_acpi_id),
		},
		.probe = mma7660_probe,
		.remove = mma7660_remove,
		.id_table = mma7660_i2c_id,
		};

		module_i2c_driver(mma7660_driver);

		MODULE_AUTHOR("Constantin Musca <constantin.musca@intel.com>");
		MODULE_DESCRIPTION("Freescale MMA7660FC 3-Axis Accelerometer driver");
		MODULE_LICENSE("GPL v2");