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 <[email protected]>
Reviewed-by: Martin Klepplinger <[email protected]>
!!
>> ---
>> 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 <[email protected]>");
>> +MODULE_DESCRIPTION("Freescale MMA7660FC 3-Axis Accelerometer driver");
>> +MODULE_LICENSE("GPL v2");
>>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-iio" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
