[PATCH v5 1/6] iio: adxl372: New driver for Analog Devices ADXL372 Accelerometer

From: Stefan Popa
Date: Tue Aug 07 2018 - 10:54:51 EST

This patch adds basic support for Analog Devices ADXL372 SPI-Bus
Three-Axis Digital Accelerometer.

The device is probed and configured the with some initial default
values. With this basic driver, it is possible to read raw acceleration
data.

Datasheet:
http://www.analog.com/media/en/technical-documentation/data-sheets/ADXL372.pdf

Signed-off-by: Stefan Popa <stefan.popa@xxxxxxxxxx>
---
MAINTAINERS | 6 +
drivers/iio/accel/Kconfig | 11 +
drivers/iio/accel/Makefile | 1 +
drivers/iio/accel/adxl372.c | 525 ++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 543 insertions(+)
create mode 100644 drivers/iio/accel/adxl372.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 60b1028..2ba47bb 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -543,6 +543,12 @@ W: http://ez.analog.com/community/linux-device-drivers
S: Supported
F: drivers/input/misc/adxl34x.c

+ADXL372 THREE-AXIS DIGITAL ACCELEROMETER DRIVER
+M: Stefan Popa <stefan.popa@xxxxxxxxxx>
+W: http://ez.analog.com/community/linux-device-drivers
+S: Supported
+F: drivers/iio/accel/adxl372.c
+
AF9013 MEDIA DRIVER
M: Antti Palosaari <crope@xxxxxx>
L: linux-media@xxxxxxxxxxxxxxx
diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index 62ae7e5..1b496ef 100644
--- a/drivers/iio/accel/Kconfig
+++ b/drivers/iio/accel/Kconfig
@@ -60,6 +60,17 @@ config ADXL345_SPI
will be called adxl345_spi and you will also get adxl345_core
for the core module.

+config ADXL372
+ tristate "Analog Devices ADXL372 3-Axis Accelerometer Driver"
+ depends on SPI
+ select IIO_BUFFER
+ select IIO_TRIGGERED_BUFFER
+ help
+ Say yes here to add support for the Analog Devices ADXL372 triaxial
+ acceleration sensor.
+ To compile this driver as a module, choose M here: the
+ module will be called adxl372.
+
config BMA180
tristate "Bosch BMA180/BMA250 3-Axis Accelerometer Driver"
depends on I2C
diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
index 636d4d1..5758ffc 100644
--- a/drivers/iio/accel/Makefile
+++ b/drivers/iio/accel/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_ADIS16209) += adis16209.o
obj-$(CONFIG_ADXL345) += adxl345_core.o
obj-$(CONFIG_ADXL345_I2C) += adxl345_i2c.o
obj-$(CONFIG_ADXL345_SPI) += adxl345_spi.o
+obj-$(CONFIG_ADXL372) += adxl372.o
obj-$(CONFIG_BMA180) += bma180.o
obj-$(CONFIG_BMA220) += bma220_spi.o
obj-$(CONFIG_BMC150_ACCEL) += bmc150-accel-core.o
diff --git a/drivers/iio/accel/adxl372.c b/drivers/iio/accel/adxl372.c
new file mode 100644
index 0000000..db9ecd2
--- /dev/null
+++ b/drivers/iio/accel/adxl372.c
@@ -0,0 +1,525 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * ADXL372 3-Axis Digital Accelerometer SPI driver
+ *
+ * Copyright 2018 Analog Devices Inc.
+ */
+
+#include <linux/bitops.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/spi/spi.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+/* ADXL372 registers definition */
+#define ADXL372_DEVID 0x00
+#define ADXL372_DEVID_MST 0x01
+#define ADXL372_PARTID 0x02
+#define ADXL372_REVID 0x03
+#define ADXL372_STATUS_1 0x04
+#define ADXL372_STATUS_2 0x05
+#define ADXL372_FIFO_ENTRIES_2 0x06
+#define ADXL372_FIFO_ENTRIES_1 0x07
+#define ADXL372_X_DATA_H 0x08
+#define ADXL372_X_DATA_L 0x09
+#define ADXL372_Y_DATA_H 0x0A
+#define ADXL372_Y_DATA_L 0x0B
+#define ADXL372_Z_DATA_H 0x0C
+#define ADXL372_Z_DATA_L 0x0D
+#define ADXL372_X_MAXPEAK_H 0x15
+#define ADXL372_X_MAXPEAK_L 0x16
+#define ADXL372_Y_MAXPEAK_H 0x17
+#define ADXL372_Y_MAXPEAK_L 0x18
+#define ADXL372_Z_MAXPEAK_H 0x19
+#define ADXL372_Z_MAXPEAK_L 0x1A
+#define ADXL372_OFFSET_X 0x20
+#define ADXL372_OFFSET_Y 0x21
+#define ADXL372_OFFSET_Z 0x22
+#define ADXL372_X_THRESH_ACT_H 0x23
+#define ADXL372_X_THRESH_ACT_L 0x24
+#define ADXL372_Y_THRESH_ACT_H 0x25
+#define ADXL372_Y_THRESH_ACT_L 0x26
+#define ADXL372_Z_THRESH_ACT_H 0x27
+#define ADXL372_Z_THRESH_ACT_L 0x28
+#define ADXL372_TIME_ACT 0x29
+#define ADXL372_X_THRESH_INACT_H 0x2A
+#define ADXL372_X_THRESH_INACT_L 0x2B
+#define ADXL372_Y_THRESH_INACT_H 0x2C
+#define ADXL372_Y_THRESH_INACT_L 0x2D
+#define ADXL372_Z_THRESH_INACT_H 0x2E
+#define ADXL372_Z_THRESH_INACT_L 0x2F
+#define ADXL372_TIME_INACT_H 0x30
+#define ADXL372_TIME_INACT_L 0x31
+#define ADXL372_X_THRESH_ACT2_H 0x32
+#define ADXL372_X_THRESH_ACT2_L 0x33
+#define ADXL372_Y_THRESH_ACT2_H 0x34
+#define ADXL372_Y_THRESH_ACT2_L 0x35
+#define ADXL372_Z_THRESH_ACT2_H 0x36
+#define ADXL372_Z_THRESH_ACT2_L 0x37
+#define ADXL372_HPF 0x38
+#define ADXL372_FIFO_SAMPLES 0x39
+#define ADXL372_FIFO_CTL 0x3A
+#define ADXL372_INT1_MAP 0x3B
+#define ADXL372_INT2_MAP 0x3C
+#define ADXL372_TIMING 0x3D
+#define ADXL372_MEASURE 0x3E
+#define ADXL372_POWER_CTL 0x3F
+#define ADXL372_SELF_TEST 0x40
+#define ADXL372_RESET 0x41
+#define ADXL372_FIFO_DATA 0x42
+
+#define ADXL372_DEVID_VAL 0xAD
+#define ADXL372_PARTID_VAL 0xFA
+#define ADXL372_RESET_CODE 0x52
+
+/* ADXL372_POWER_CTL */
+#define ADXL372_POWER_CTL_MODE_MSK GENMASK_ULL(1, 0)
+#define ADXL372_POWER_CTL_MODE(x) (((x) & 0x3) << 0)
+
+/* ADXL372_MEASURE */
+#define ADXL372_MEASURE_LINKLOOP_MSK GENMASK_ULL(5, 4)
+#define ADXL372_MEASURE_LINKLOOP_MODE(x) (((x) & 0x3) << 4)
+#define ADXL372_MEASURE_BANDWIDTH_MSK GENMASK_ULL(2, 0)
+#define ADXL372_MEASURE_BANDWIDTH_MODE(x) (((x) & 0x7) << 0)
+
+/* ADXL372_TIMING */
+#define ADXL372_TIMING_ODR_MSK GENMASK_ULL(7, 5)
+#define ADXL372_TIMING_ODR_MODE(x) (((x) & 0x7) << 5)
+
+/* ADXL372_FIFO_CTL */
+#define ADXL372_FIFO_CTL_FORMAT_MSK GENMASK(5, 3)
+#define ADXL372_FIFO_CTL_FORMAT_MODE(x) (((x) & 0x7) << 3)
+#define ADXL372_FIFO_CTL_MODE_MSK GENMASK(2, 1)
+#define ADXL372_FIFO_CTL_MODE_MODE(x) (((x) & 0x3) << 1)
+#define ADXL372_FIFO_CTL_SAMPLES_MSK BIT(1)
+#define ADXL372_FIFO_CTL_SAMPLES_MODE(x) (((x) > 0xFF) ? 1 : 0)
+
+/* ADXL372_STATUS_1 */
+#define ADXL372_STATUS_1_DATA_RDY(x) (((x) >> 0) & 0x1)
+#define ADXL372_STATUS_1_FIFO_RDY(x) (((x) >> 1) & 0x1)
+#define ADXL372_STATUS_1_FIFO_FULL(x) (((x) >> 2) & 0x1)
+#define ADXL372_STATUS_1_FIFO_OVR(x) (((x) >> 3) & 0x1)
+#define ADXL372_STATUS_1_USR_NVM_BUSY(x) (((x) >> 5) & 0x1)
+#define ADXL372_STATUS_1_AWAKE(x) (((x) >> 6) & 0x1)
+#define ADXL372_STATUS_1_ERR_USR_REGS(x) (((x) >> 7) & 0x1)
+
+/* ADXL372_INT1_MAP */
+#define ADXL372_INT1_MAP_DATA_RDY_MSK BIT(0)
+#define ADXL372_INT1_MAP_DATA_RDY_MODE(x) (((x) & 0x1) << 0)
+#define ADXL372_INT1_MAP_FIFO_RDY_MSK BIT(1)
+#define ADXL372_INT1_MAP_FIFO_RDY_MODE(x) (((x) & 0x1) << 1)
+#define ADXL372_INT1_MAP_FIFO_FULL_MSK BIT(2)
+#define ADXL372_INT1_MAP_FIFO_FULL_MODE(x) (((x) & 0x1) << 2)
+#define ADXL372_INT1_MAP_FIFO_OVR_MSK BIT(3)
+#define ADXL372_INT1_MAP_FIFO_OVR_MODE(x) (((x) & 0x1) << 3)
+#define ADXL372_INT1_MAP_INACT_MSK BIT(4)
+#define ADXL372_INT1_MAP_INACT_MODE(x) (((x) & 0x1) << 4)
+#define ADXL372_INT1_MAP_ACT_MSK BIT(5)
+#define ADXL372_INT1_MAP_ACT_MODE(x) (((x) & 0x1) << 5)
+#define ADXL372_INT1_MAP_AWAKE_MSK BIT(6)
+#define ADXL372_INT1_MAP_AWAKE_MODE(x) (((x) & 0x1) << 6)
+#define ADXL372_INT1_MAP_LOW_MSK BIT(7)
+#define ADXL372_INT1_MAP_LOW_MODE(x) (((x) & 0x1) << 7)
+
+/*
+ * At +/- 200g with 12-bit resolution, scale is computed as:
+ * (200 + 200) * 9.81 / (2^12 - 1) = 0.958241
+ */
+#define ADXL372_USCALE 958241
+
+enum adxl372_op_mode {
+ ADXL372_STANDBY,
+ ADXL372_WAKE_UP,
+ ADXL372_INSTANT_ON,
+ ADXL372_FULL_BW_MEASUREMENT,
+};
+
+enum adxl372_act_proc_mode {
+ ADXL372_DEFAULT,
+ ADXL372_LINKED,
+ ADXL372_LOOPED,
+};
+
+enum adxl372_th_activity {
+ ADXL372_ACTIVITY,
+ ADXL372_ACTIVITY2,
+ ADXL372_INACTIVITY,
+};
+
+enum adxl372_odr {
+ ADXL372_ODR_400HZ,
+ ADXL372_ODR_800HZ,
+ ADXL372_ODR_1600HZ,
+ ADXL372_ODR_3200HZ,
+ ADXL372_ODR_6400HZ,
+};
+
+enum adxl372_bandwidth {
+ ADXL372_BW_200HZ,
+ ADXL372_BW_400HZ,
+ ADXL372_BW_800HZ,
+ ADXL372_BW_1600HZ,
+ ADXL372_BW_3200HZ,
+};
+
+static const unsigned int adxl372_th_reg_high_addr[3] = {
+ [ADXL372_ACTIVITY] = ADXL372_X_THRESH_ACT_H,
+ [ADXL372_ACTIVITY2] = ADXL372_X_THRESH_ACT2_H,
+ [ADXL372_INACTIVITY] = ADXL372_X_THRESH_INACT_H,
+};
+
+#define ADXL372_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 const struct iio_chan_spec adxl372_channels[] = {
+ ADXL372_ACCEL_CHANNEL(0, ADXL372_X_DATA_H, X),
+ ADXL372_ACCEL_CHANNEL(1, ADXL372_Y_DATA_H, Y),
+ ADXL372_ACCEL_CHANNEL(2, ADXL372_Z_DATA_H, Z),
+};
+
+struct adxl372_state {
+ struct spi_device *spi;
+ struct regmap *regmap;
+ enum adxl372_op_mode op_mode;
+ enum adxl372_act_proc_mode act_proc_mode;
+ enum adxl372_odr odr;
+ enum adxl372_bandwidth bw;
+ u32 act_time_ms;
+ u32 inact_time_ms;
+};
+
+static int adxl372_read_axis(struct adxl372_state *st, u8 addr)
+{
+ __be16 regval;
+ int ret;
+
+ ret = regmap_bulk_read(st->regmap, addr, &regval, sizeof(regval));
+ if (ret < 0)
+ return ret;
+
+ return be16_to_cpu(regval);
+}
+
+static int adxl372_set_op_mode(struct adxl372_state *st,
+ enum adxl372_op_mode op_mode)
+{
+ int ret;
+
+ ret = regmap_update_bits(st->regmap, ADXL372_POWER_CTL,
+ ADXL372_POWER_CTL_MODE_MSK,
+ ADXL372_POWER_CTL_MODE(op_mode));
+ if (ret < 0)
+ return ret;
+
+ st->op_mode = op_mode;
+
+ return ret;
+}
+
+static int adxl372_set_odr(struct adxl372_state *st,
+ enum adxl372_odr odr)
+{
+ int ret;
+
+ ret = regmap_update_bits(st->regmap, ADXL372_TIMING,
+ ADXL372_TIMING_ODR_MSK,
+ ADXL372_TIMING_ODR_MODE(odr));
+ if (ret < 0)
+ return ret;
+
+ st->odr = odr;
+
+ return ret;
+}
+
+static int adxl372_set_bandwidth(struct adxl372_state *st,
+ enum adxl372_bandwidth bw)
+{
+ int ret;
+
+ ret = regmap_update_bits(st->regmap, ADXL372_MEASURE,
+ ADXL372_MEASURE_BANDWIDTH_MSK,
+ ADXL372_MEASURE_BANDWIDTH_MODE(bw));
+ if (ret < 0)
+ return ret;
+
+ st->bw = bw;
+
+ return ret;
+}
+
+static int adxl372_set_act_proc_mode(struct adxl372_state *st,
+ enum adxl372_act_proc_mode mode)
+{
+ int ret;
+
+ ret = regmap_update_bits(st->regmap,
+ ADXL372_MEASURE,
+ ADXL372_MEASURE_LINKLOOP_MSK,
+ ADXL372_MEASURE_LINKLOOP_MODE(mode));
+ if (ret < 0)
+ return ret;
+
+ st->act_proc_mode = mode;
+
+ return ret;
+}
+
+static int adxl372_set_activity_threshold(struct adxl372_state *st,
+ enum adxl372_th_activity act,
+ bool ref_en, bool enable,
+ unsigned int threshold)
+{
+ unsigned char buf[6];
+ unsigned char th_reg_high_val, th_reg_low_val, th_reg_high_addr;
+
+ /* scale factor is 100 mg/code */
+ th_reg_high_val = (threshold / 100) >> 3;
+ th_reg_low_val = ((threshold / 100) << 5) | (ref_en << 1) | enable;
+ th_reg_high_addr = adxl372_th_reg_high_addr[act];
+
+ buf[0] = th_reg_high_val;
+ buf[1] = th_reg_low_val;
+ buf[2] = th_reg_high_val;
+ buf[3] = th_reg_low_val;
+ buf[4] = th_reg_high_val;
+ buf[5] = th_reg_low_val;
+
+ return regmap_bulk_write(st->regmap, th_reg_high_addr,
+ buf, ARRAY_SIZE(buf));
+}
+
+static int adxl372_set_activity_time_ms(struct adxl372_state *st,
+ unsigned int act_time_ms)
+{
+ unsigned int reg_val, scale_factor;
+ int ret;
+
+ /*
+ * 3.3 ms per code is the scale factor of the TIME_ACT register for
+ * ODR = 6400 Hz. It is 6.6 ms per code for ODR = 3200 Hz and below.
+ */
+ if (st->odr == ADXL372_ODR_6400HZ)
+ scale_factor = 3300;
+ else
+ scale_factor = 6600;
+
+ reg_val = DIV_ROUND_CLOSEST(act_time_ms * 1000, scale_factor);
+
+ /* TIME_ACT register is 8 bits wide */
+ if (reg_val > 0xFF)
+ reg_val = 0xFF;
+
+ ret = regmap_write(st->regmap, ADXL372_TIME_ACT, reg_val);
+ if (ret < 0)
+ return ret;
+
+ st->act_time_ms = act_time_ms;
+
+ return ret;
+}
+
+static int adxl372_set_inactivity_time_ms(struct adxl372_state *st,
+ unsigned int inact_time_ms)
+{
+ unsigned int reg_val_h, reg_val_l, res, scale_factor;
+ int ret;
+
+ /*
+ * 13 ms per code is the scale factor of the TIME_INACT register for
+ * ODR = 6400 Hz. It is 26 ms per code for ODR = 3200 Hz and below.
+ */
+ if (st->odr == ADXL372_ODR_6400HZ)
+ scale_factor = 13;
+ else
+ scale_factor = 26;
+
+ res = DIV_ROUND_CLOSEST(inact_time_ms, scale_factor);
+ reg_val_h = (res >> 8) & 0xFF;
+ reg_val_l = res & 0xFF;
+
+ ret = regmap_write(st->regmap, ADXL372_TIME_INACT_H, reg_val_h);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_write(st->regmap, ADXL372_TIME_INACT_L, reg_val_l);
+ if (ret < 0)
+ return ret;
+
+ st->inact_time_ms = inact_time_ms;
+
+ return ret;
+}
+
+static int adxl372_setup(struct adxl372_state *st)
+{
+ unsigned int regval;
+ int ret;
+
+ ret = regmap_read(st->regmap, ADXL372_DEVID, &regval);
+ if (ret < 0)
+ return ret;
+
+ if (regval != ADXL372_DEVID_VAL) {
+ dev_err(&st->spi->dev, "Invalid chip id %x\n", regval);
+ return -ENODEV;
+ }
+
+ ret = adxl372_set_op_mode(st, ADXL372_STANDBY);
+ if (ret < 0)
+ return ret;
+
+ /* Set threshold for activity detection to 1g */
+ ret = adxl372_set_activity_threshold(st, ADXL372_ACTIVITY,
+ true, true, 1000);
+ if (ret < 0)
+ return ret;
+
+ /* Set threshold for inactivity detection to 100mg */
+ ret = adxl372_set_activity_threshold(st, ADXL372_INACTIVITY,
+ true, true, 100);
+ if (ret < 0)
+ return ret;
+
+ /* Set activity processing in Looped mode */
+ ret = adxl372_set_act_proc_mode(st, ADXL372_LOOPED);
+ if (ret < 0)
+ return ret;
+
+ ret = adxl372_set_odr(st, ADXL372_ODR_6400HZ);
+ if (ret < 0)
+ return ret;
+
+ ret = adxl372_set_bandwidth(st, ADXL372_BW_3200HZ);
+ if (ret < 0)
+ return ret;
+
+ /* Set activity timer to 1ms */
+ ret = adxl372_set_activity_time_ms(st, 1);
+ if (ret < 0)
+ return ret;
+
+ /* Set inactivity timer to 10s */
+ ret = adxl372_set_inactivity_time_ms(st, 10000);
+ if (ret < 0)
+ return ret;
+
+ /* Set the mode of operation to full bandwidth measurement mode */
+ return adxl372_set_op_mode(st, ADXL372_FULL_BW_MEASUREMENT);
+}
+
+static int adxl372_reg_access(struct iio_dev *indio_dev,
+ unsigned int reg,
+ unsigned int writeval,
+ unsigned int *readval)
+{
+ struct adxl372_state *st = iio_priv(indio_dev);
+
+ if (readval)
+ return regmap_read(st->regmap, reg, readval);
+ else
+ return regmap_write(st->regmap, reg, writeval);
+}
+
+static int adxl372_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long info)
+{
+ struct adxl372_state *st = iio_priv(indio_dev);
+ int ret;
+
+ switch (info) {
+ case IIO_CHAN_INFO_RAW:
+ ret = adxl372_read_axis(st, chan->address);
+ if (ret < 0)
+ return ret;
+
+ *val = sign_extend32(ret >> chan->scan_type.shift,
+ chan->scan_type.realbits - 1);
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ *val = 0;
+ *val2 = ADXL372_USCALE;
+ return IIO_VAL_INT_PLUS_MICRO;
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct iio_info adxl372_info = {
+ .read_raw = adxl372_read_raw,
+ .debugfs_reg_access = &adxl372_reg_access,
+};
+
+static const struct regmap_config adxl372_spi_regmap_config = {
+ .reg_bits = 7,
+ .pad_bits = 1,
+ .val_bits = 8,
+ .read_flag_mask = BIT(0),
+};
+
+static int adxl372_probe(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev;
+ struct adxl372_state *st;
+ struct regmap *regmap;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ st = iio_priv(indio_dev);
+ spi_set_drvdata(spi, indio_dev);
+
+ st->spi = spi;
+
+ regmap = devm_regmap_init_spi(spi, &adxl372_spi_regmap_config);
+ if (IS_ERR(regmap))
+ return PTR_ERR(regmap);
+
+ st->regmap = regmap;
+
+ indio_dev->channels = adxl372_channels;
+ indio_dev->num_channels = ARRAY_SIZE(adxl372_channels);
+ indio_dev->dev.parent = &spi->dev;
+ indio_dev->name = spi_get_device_id(spi)->name;
+ indio_dev->info = &adxl372_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ ret = adxl372_setup(st);
+ if (ret < 0) {
+ dev_err(&st->spi->dev, "ADXL372 setup failed\n");
+ return ret;
+ }
+
+ return devm_iio_device_register(&st->spi->dev, indio_dev);
+}
+
+static const struct spi_device_id adxl372_id[] = {
+ { "adxl372", 0 },
+ {}
+};
+MODULE_DEVICE_TABLE(spi, adxl372_id);
+
+static struct spi_driver adxl372_driver = {
+ .driver = {
+ .name = KBUILD_MODNAME,
+ },
+ .probe = adxl372_probe,
+ .id_table = adxl372_id,
+};
+
+module_spi_driver(adxl372_driver);
+
+MODULE_AUTHOR("Stefan Popa <stefan.popa@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Analog Devices ADXL372 3-axis accelerometer driver");
+MODULE_LICENSE("GPL v2");
--
2.7.4