Re: [PATCH v3] iio: accel: Add support for Freescale MMA7660FC

[Jonathan Cameron]

On 01/05/16 19:20, Jonathan Cameron wrote:
> On 29/04/16 14:08, Martin Kepplinger wrote:
>> Am 2016-04-29 um 14:19 schrieb Constantin Musca:
>>> Minimal implementation of an IIO driver for the Freescale
>>> MMA7660FC 3-axis accelerometer. Datasheet:
>>> http://www.freescale.com.cn/files/sensors/doc/data_sheet/MMA7660FC.pdf
>>
>> it's nxp.com now, which would probably be valid for a longer time.
>>
>> Theoretically there would be a way to add it to mma8452, but with quite
>> some rewriting of register definitions. I guess it's ok to start over
>> here to keep it simple. If everyone is aware of this, feel free to add
>> my reviewed-by.
> Martin - formal tags please! and in the right place...
>>
>> Are you planning to support it's orienation detection via iio in the future?
>>
>>                       martin
>>
>>>
>>> Includes:
>>> - ACPI support;
>>> - read_raw for x,y,z axes;
>>> - reading and setting the scale (range) parameter.
>>> - power management
>>>
>>> Signed-off-by: Constantin Musca <constantin.musca@xxxxxxxxx>
> Reviewed-by: Martin Klepplinger <martink@xxxxxxxxx>
> 
> !!
I nearly missed this when actually applying the patch - just added
the tag...
> 
>>> ---
>>>  drivers/iio/accel/Kconfig   |  10 ++
>>>  drivers/iio/accel/Makefile  |   2 +
>>>  drivers/iio/accel/mma7660.c | 269 ++++++++++++++++++++++++++++++++++++++++++++
>>>  3 files changed, 281 insertions(+)
>>>  create mode 100644 drivers/iio/accel/mma7660.c
>>>
>>> diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
>>> index e4a758c..1df6361 100644
>>> --- a/drivers/iio/accel/Kconfig
>>> +++ b/drivers/iio/accel/Kconfig
>>> @@ -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
>>> diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
>>> index 71b6794..ba1165f 100644
>>> --- a/drivers/iio/accel/Makefile
>>> +++ b/drivers/iio/accel/Makefile
>>> @@ -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
>>> diff --git a/drivers/iio/accel/mma7660.c b/drivers/iio/accel/mma7660.c
>>> new file mode 100644
>>> index 0000000..94b2999
>>> --- /dev/null
>>> +++ b/drivers/iio/accel/mma7660.c
>>> @@ -0,0 +1,269 @@
>>> +/**
>>> + * 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;
>>> +
>>> +	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@xxxxxxxxx>");
>>> +MODULE_DESCRIPTION("Freescale MMA7660FC 3-Axis Accelerometer driver");
>>> +MODULE_LICENSE("GPL v2");
>>>
>>
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