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iio: accel: Add support for Bosch BMA220 

This commit adds basic support for the Bosch Sensortec BMA220
digital triaxial acceleration sensor.
The device datasheet can be found here:

http://www.mouser.com/pdfdocs/BSTBMA220DS00308.PDF

Includes:
- raw readings
- ACPI detection
- power management

Signed-off-by: Tiberiu Breana <tiberiu.a.breana@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
hifive-unleashed-5.1
Tiberiu Breana 2016-05-05 18:48:55 +03:00 committed by Jonathan Cameron
parent 2763ac94f3
commit bf2a5600a3
3 changed files with 288 additions and 0 deletions
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10
drivers/iio/accel/Kconfig
View File

@ -17,6 +17,16 @@ config BMA180
To compile this driver as a module, choose M here: the
module will be called bma180.
config BMA220
tristate "Bosch BMA220 3-Axis Accelerometer Driver"
depends on SPI
help
Say yes here to add support for the Bosch BMA220 triaxial
acceleration sensor.
To compile this driver as a module, choose M here: the
module will be called bma220_spi.
config BMC150_ACCEL
tristate "Bosch BMC150 Accelerometer Driver"
select IIO_BUFFER

1
drivers/iio/accel/Makefile
View File

@ -4,6 +4,7 @@
# When adding new entries keep the list in alphabetical order
obj-$(CONFIG_BMA180) += bma180.o
obj-$(CONFIG_BMA220) += bma220_spi.o
obj-$(CONFIG_BMC150_ACCEL) += bmc150-accel-core.o
obj-$(CONFIG_BMC150_ACCEL_I2C) += bmc150-accel-i2c.o
obj-$(CONFIG_BMC150_ACCEL_SPI) += bmc150-accel-spi.o

277
drivers/iio/accel/bma220_spi.c 100644
View File

@ -0,0 +1,277 @@
/**
* BMA220 Digital triaxial acceleration sensor driver
*
* 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.
*/
#include <linux/acpi.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/spi/spi.h>
#define BMA220_REG_ID 0x00
#define BMA220_REG_ACCEL_X 0x02
#define BMA220_REG_ACCEL_Y 0x03
#define BMA220_REG_ACCEL_Z 0x04
#define BMA220_REG_RANGE 0x11
#define BMA220_REG_SUSPEND 0x18
#define BMA220_CHIP_ID 0xDD
#define BMA220_READ_MASK 0x80
#define BMA220_RANGE_MASK 0x03
#define BMA220_DATA_SHIFT 2
#define BMA220_SUSPEND_SLEEP 0xFF
#define BMA220_SUSPEND_WAKE 0x00
#define BMA220_DEVICE_NAME "bma220"
#define BMA220_SCALE_AVAILABLE "0.623 1.248 2.491 4.983"
#define BMA220_ACCEL_CHANNEL(index, 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 IIO_CONST_ATTR(in_accel_scale_available, BMA220_SCALE_AVAILABLE);
static struct attribute *bma220_attributes[] = {
&iio_const_attr_in_accel_scale_available.dev_attr.attr,
NULL,
};
static const struct attribute_group bma220_attribute_group = {
.attrs = bma220_attributes,
};
static const int bma220_scale_table[][4] = {
{0, 623000}, {1, 248000}, {2, 491000}, {4, 983000}
};
struct bma220_data {
struct spi_device *spi_device;
struct mutex lock;
u8 tx_buf[2] ____cacheline_aligned;
};
static const struct iio_chan_spec bma220_channels[] = {
BMA220_ACCEL_CHANNEL(0, BMA220_REG_ACCEL_X, X),
BMA220_ACCEL_CHANNEL(1, BMA220_REG_ACCEL_Y, Y),
BMA220_ACCEL_CHANNEL(2, BMA220_REG_ACCEL_Z, Z),
};
static inline int bma220_read_reg(struct spi_device *spi, u8 reg)
{
return spi_w8r8(spi, reg | BMA220_READ_MASK);
}
static int bma220_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
int ret;
u8 range_idx;
struct bma220_data *data = iio_priv(indio_dev);
switch (mask) {
case IIO_CHAN_INFO_RAW:
ret = bma220_read_reg(data->spi_device, chan->address);
if (ret < 0)
return -EINVAL;
*val = sign_extend32(ret >> BMA220_DATA_SHIFT, 5);
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
ret = bma220_read_reg(data->spi_device, BMA220_REG_RANGE);
if (ret < 0)
return ret;
range_idx = ret & BMA220_RANGE_MASK;
*val = bma220_scale_table[range_idx][0];
*val2 = bma220_scale_table[range_idx][1];
return IIO_VAL_INT_PLUS_MICRO;
}
return -EINVAL;
}
static int bma220_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
int i;
int ret;
int index = -1;
struct bma220_data *data = iio_priv(indio_dev);
switch (mask) {
case IIO_CHAN_INFO_SCALE:
for (i = 0; i < ARRAY_SIZE(bma220_scale_table); i++)
if (val == bma220_scale_table[i][0] &&
val2 == bma220_scale_table[i][1]) {
index = i;
break;
}
if (index < 0)
return -EINVAL;
mutex_lock(&data->lock);
data->tx_buf[0] = BMA220_REG_RANGE;
data->tx_buf[1] = index;
ret = spi_write(data->spi_device, data->tx_buf,
sizeof(data->tx_buf));
if (ret < 0)
dev_err(&data->spi_device->dev,
"failed to set measurement range\n");
mutex_unlock(&data->lock);
return 0;
}
return -EINVAL;
}
static const struct iio_info bma220_info = {
.driver_module = THIS_MODULE,
.read_raw = bma220_read_raw,
.write_raw = bma220_write_raw,
.attrs = &bma220_attribute_group,
};
static int bma220_init(struct spi_device *spi)
{
int ret;
ret = bma220_read_reg(spi, BMA220_REG_ID);
if (ret != BMA220_CHIP_ID)
return -ENODEV;
/* Make sure the chip is powered on */
ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
if (ret < 0)
return ret;
else if (ret == BMA220_SUSPEND_WAKE)
return bma220_read_reg(spi, BMA220_REG_SUSPEND);
return 0;
}
static int bma220_deinit(struct spi_device *spi)
{
int ret;
/* Make sure the chip is powered off */
ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
if (ret < 0)
return ret;
else if (ret == BMA220_SUSPEND_SLEEP)
return bma220_read_reg(spi, BMA220_REG_SUSPEND);
return 0;
}
static int bma220_probe(struct spi_device *spi)
{
int ret;
struct iio_dev *indio_dev;
struct bma220_data *data;
indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data));
if (!indio_dev) {
dev_err(&spi->dev, "iio allocation failed!\n");
return -ENOMEM;
}
data = iio_priv(indio_dev);
data->spi_device = spi;
spi_set_drvdata(spi, indio_dev);
mutex_init(&data->lock);
indio_dev->dev.parent = &spi->dev;
indio_dev->info = &bma220_info;
indio_dev->name = BMA220_DEVICE_NAME;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = bma220_channels;
indio_dev->num_channels = ARRAY_SIZE(bma220_channels);
ret = bma220_init(data->spi_device);
if (ret < 0)
return ret;
ret = iio_device_register(indio_dev);
if (ret < 0) {
dev_err(&spi->dev, "iio_device_register failed\n");
return bma220_deinit(spi);
}
return ret;
}
static int bma220_remove(struct spi_device *spi)
{
struct iio_dev *indio_dev = spi_get_drvdata(spi);
iio_device_unregister(indio_dev);
return bma220_deinit(spi);
}
#ifdef CONFIG_PM_SLEEP
static int bma220_suspend(struct device *dev)
{
struct bma220_data *data =
iio_priv(spi_get_drvdata(to_spi_device(dev)));
/* The chip can be suspended/woken up by a simple register read. */
return bma220_read_reg(data->spi_device, BMA220_REG_SUSPEND);
}
static int bma220_resume(struct device *dev)
{
struct bma220_data *data =
iio_priv(spi_get_drvdata(to_spi_device(dev)));
return bma220_read_reg(data->spi_device, BMA220_REG_SUSPEND);
}
static SIMPLE_DEV_PM_OPS(bma220_pm_ops, bma220_suspend, bma220_resume);
#define BMA220_PM_OPS (&bma220_pm_ops)
#else
#define BMA220_PM_OPS NULL
#endif
static const struct spi_device_id bma220_spi_id[] = {
{"bma220", 0},
{}
};
static const struct acpi_device_id bma220_acpi_id[] = {
{"BMA0220", 0},
{}
};
MODULE_DEVICE_TABLE(spi, bma220_spi_id);
static struct spi_driver bma220_driver = {
.driver = {
.name = "bma220_spi",
.pm = BMA220_PM_OPS,
.acpi_match_table = ACPI_PTR(bma220_acpi_id),
},
.probe = bma220_probe,
.remove = bma220_remove,
.id_table = bma220_spi_id,
};
module_spi_driver(bma220_driver);
MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
MODULE_DESCRIPTION("BMA220 acceleration sensor driver");
MODULE_LICENSE("GPL v2");