> Add an IIO driver for the mCube MC3230 3-axis accelerometer.
comments below
> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
> ---
> .../devicetree/bindings/i2c/trivial-devices.txt | 1 +
> drivers/iio/accel/Kconfig | 10 +
> drivers/iio/accel/Makefile | 1 +
> drivers/iio/accel/mc3230.c | 225 +++++++++++++++++++++
> 4 files changed, 237 insertions(+)
> create mode 100644 drivers/iio/accel/mc3230.c
>
> diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
> index badf5eb..fbbad64 100644
> --- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt
> +++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
> @@ -56,6 +56,7 @@ maxim,ds1050 5 Bit Programmable, Pulse-Width Modulator
> maxim,max1237 Low-Power, 4-/12-Channel, 2-Wire Serial, 12-Bit ADCs
> maxim,max6625 9-Bit/12-Bit Temperature Sensors with I²C-Compatible Serial Interface
> mc,rv3029c2 Real Time Clock Module with I2C-Bus
> +mcube,mc3230 mCube 3-axis 8-bit digital accelerometer
> microchip,mcp4531-502 Microchip 7-bit Single I2C Digital Potentiometer (5k)
> microchip,mcp4531-103 Microchip 7-bit Single I2C Digital Potentiometer (10k)
> microchip,mcp4531-503 Microchip 7-bit Single I2C Digital Potentiometer (50k)
> diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
> index 5630f23..3aee97d 100644
> --- a/drivers/iio/accel/Kconfig
> +++ b/drivers/iio/accel/Kconfig
> @@ -138,6 +138,16 @@ config KXCJK1013
> To compile this driver as a module, choose M here: the module will
> be called kxcjk-1013.
>
> +config MC3230
> + tristate "mCube MC3230 Digital Accelerometer Driver"
> + depends on I2C
> + help
> + Say yes here to build support for the mCube MC3230 low-g tri-axial
> + digital accelerometer.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called mc3230.
> +
> config MMA7455
> tristate
> select IIO_BUFFER
> diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
> index e974841..07a0c72 100644
> --- a/drivers/iio/accel/Makefile
> +++ b/drivers/iio/accel/Makefile
> @@ -13,6 +13,7 @@ obj-$(CONFIG_DMARD09) += dmard09.o
> obj-$(CONFIG_HID_SENSOR_ACCEL_3D) += hid-sensor-accel-3d.o
> obj-$(CONFIG_KXCJK1013) += kxcjk-1013.o
> obj-$(CONFIG_KXSD9) += kxsd9.o
> +obj-$(CONFIG_MC3230) += mc3230.o
>
> obj-$(CONFIG_MMA7455) += mma7455_core.o
> obj-$(CONFIG_MMA7455_I2C) += mma7455_i2c.o
> diff --git a/drivers/iio/accel/mc3230.c b/drivers/iio/accel/mc3230.c
> new file mode 100644
> index 0000000..21127a9
> --- /dev/null
> +++ b/drivers/iio/accel/mc3230.c
> @@ -0,0 +1,225 @@
> +/**
> + * mCube MC3230 3-Axis Accelerometer
> + *
> + * Copyright (c) 2016 Hans de Goede <hdegoede@xxxxxxxxxx>
> + *
> + * 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.
> + *
> + * IIO driver for mCube MC3230; 7-bit I2C address: 0x4c.
> + */
> +
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +
> +#define MC3230_REG_XOUT 0x00
> +#define MC3230_REG_YOUT 0x01
> +#define MC3230_REG_ZOUT 0x02
> +
> +#define MC3230_REG_MODE 0x07
> +#define MC3230_MODE_OPCON_MASK 0x03
> +#define MC3230_MODE_OPCON_WAKE 0x01
> +#define MC3230_MODE_OPCON_STANDBY 0x03
> +
> +#define MC3230_REG_CHIP_ID 0x18
> +#define MC3230_CHIP_ID 0x01
> +
> +#define MC3230_REG_PRODUCT_CODE 0x3b
> +#define MC3230_PRODUCT_CODE 0x19
> +
> +/*
> + * The accelerometer has one measurement range:
> + *
> + * -1.5g - +1.5g (8-bit, signed)
> + *
> + * scale = (1.5 + 1.5) * 9.81 / (2^8 - 1) = 0.115411765
> + */
> +
> +#define MC3230_SCALE_AVAIL "0.115411765"
> +
> +const int mc3230_nscale = 115411765;
static
> +
> +#define MC3230_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 mc3230_channels[] = {
> + MC3230_CHANNEL(MC3230_REG_XOUT, X),
> + MC3230_CHANNEL(MC3230_REG_YOUT, Y),
> + MC3230_CHANNEL(MC3230_REG_ZOUT, Z),
> +};
> +
> +struct mc3230_data {
> + struct i2c_client *client;
> +};
> +
> +static IIO_CONST_ATTR(in_accel_scale_available, MC3230_SCALE_AVAIL);
> +
> +static struct attribute *mc3230_attributes[] = {
> + &iio_const_attr_in_accel_scale_available.dev_attr.attr,
> + NULL,
> +};
> +
> +static const struct attribute_group mc3230_attribute_group = {
> + .attrs = mc3230_attributes
> +};
> +
> +static int mc3230_set_opcon(struct mc3230_data *data, int opcon)
> +{
> + int ret;
> + struct i2c_client *client = data->client;
> +
guess we want locking here
> + ret = i2c_smbus_read_byte_data(client, MC3230_REG_MODE);
> + if (ret < 0) {
> + dev_err(&client->dev, "failed to read mode reg: %d\n", ret);
> + return ret;
> + }
> +
> + ret &= ~MC3230_MODE_OPCON_MASK;
> + ret |= opcon;
> +
> + ret = i2c_smbus_write_byte_data(client, MC3230_REG_MODE, ret);
> + if (ret < 0) {
> + dev_err(&client->dev, "failed to write mode reg: %d\n", ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int mc3230_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int *val, int *val2, long mask)
> +{
> + struct mc3230_data *data = iio_priv(indio_dev);
> + int ret;
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW:
> + ret = i2c_smbus_read_byte_data(data->client, chan->address);
> + if (ret < 0)
> + return ret;
> + *val = sign_extend32(ret, 7);
> + return IIO_VAL_INT;
> + case IIO_CHAN_INFO_SCALE:
> + *val = 0;
> + *val2 = mc3230_nscale;
> + return IIO_VAL_INT_PLUS_NANO;
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static const struct iio_info mc3230_info = {
> + .driver_module = THIS_MODULE,
> + .read_raw = mc3230_read_raw,
> + .attrs = &mc3230_attribute_group,
> +};
> +
> +static int mc3230_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
> +{
> + int ret;
> + struct iio_dev *indio_dev;
> + struct mc3230_data *data;
> +
> + /* First check chip-id and product-id */
> + ret = i2c_smbus_read_byte_data(client, MC3230_REG_CHIP_ID);
> + if (ret != MC3230_CHIP_ID)
> + return (ret < 0) ? ret : -ENODEV;
> +
> + ret = i2c_smbus_read_byte_data(client, MC3230_REG_PRODUCT_CODE);
> + if (ret != MC3230_PRODUCT_CODE)
> + return (ret < 0) ? ret : -ENODEV;
> +
> + 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);
> +
> + indio_dev->dev.parent = &client->dev;
> + indio_dev->info = &mc3230_info;
> + indio_dev->name = "mc3230";
> + indio_dev->modes = INDIO_DIRECT_MODE;
> + indio_dev->channels = mc3230_channels;
> + indio_dev->num_channels = ARRAY_SIZE(mc3230_channels);
> +
> + ret = mc3230_set_opcon(data, MC3230_MODE_OPCON_WAKE);
> + if (ret < 0)
> + return ret;
> +
> + ret = iio_device_register(indio_dev);
> + if (ret < 0) {
> + dev_err(&client->dev, "device_register failed\n");
> + mc3230_set_opcon(data, MC3230_MODE_OPCON_STANDBY);
> + }
> +
> + return ret;
> +}
> +
> +static int mc3230_remove(struct i2c_client *client)
> +{
> + struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> + iio_device_unregister(indio_dev);
> +
> + return mc3230_set_opcon(iio_priv(indio_dev), MC3230_MODE_OPCON_STANDBY);
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int mc3230_suspend(struct device *dev)
> +{
> + struct mc3230_data *data;
> +
> + data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
> +
> + return mc3230_set_opcon(data, MC3230_MODE_OPCON_STANDBY);
> +}
> +
> +static int mc3230_resume(struct device *dev)
> +{
> + struct mc3230_data *data;
> +
> + data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
> +
> + return mc3230_set_opcon(data, MC3230_MODE_OPCON_WAKE);
> +}
> +#endif
> +
> +static SIMPLE_DEV_PM_OPS(mc3230_pm_ops, mc3230_suspend, mc3230_resume);
> +
> +static const struct i2c_device_id mc3230_i2c_id[] = {
> + {"mc3230", 0},
> + {}
> +};
> +MODULE_DEVICE_TABLE(i2c, mc3230_i2c_id);
> +
> +static struct i2c_driver mc3230_driver = {
> + .driver = {
> + .name = "mc3230",
> + .pm = &mc3230_pm_ops,
> + },
> + .probe = mc3230_probe,
> + .remove = mc3230_remove,
> + .id_table = mc3230_i2c_id,
> +};
> +
> +module_i2c_driver(mc3230_driver);
> +
> +MODULE_AUTHOR("Hans de Goede <hdegoede@xxxxxxxxxx>");
> +MODULE_DESCRIPTION("mCube MC3230 3-Axis Accelerometer driver");
> +MODULE_LICENSE("GPL v2");
>
--
Peter Meerwald-Stadler
+43-664-2444418 (mobile)
