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linux/drivers/iio/accel/mma8452.c
Javier Martinez Canillas 119c4fce68 iio: Export OF module alias information in missing drivers 
The I2C core always reports the MODALIAS uevent as "i2c:<client name"
regardless if the driver was matched using the I2C id_table or the
of_match_table. So technically there's no need for a driver to export
the OF table since currently it's not used.

In fact, the I2C device ID table is mandatory for I2C drivers since
a i2c_device_id is passed to the driver's probe function even if the
I2C core used the OF table to match the driver.

And since the I2C core uses different tables, OF-only drivers needs to
have duplicated data that has to be kept in sync and also the dev node
compatible manufacturer prefix is stripped when reporting the MODALIAS.

To avoid the above, the I2C core behavior may be changed in the future
to not require an I2C device table for OF-only drivers and report the
OF module alias. So, it's better to also export the OF table to prevent
breaking module autoloading if that happens.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-08-02 16:36:00 +01:00

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/*
* mma8452.c - Support for Freescale MMA8452Q 3-axis 12-bit accelerometer
*
* Copyright 2014 Peter Meerwald <pmeerw@pmeerw.net>
*
* 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.
*
* 7-bit I2C slave address 0x1c/0x1d (pin selectable)
*
* TODO: orientation / freefall events, autosleep
*/
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/buffer.h>
#include <linux/iio/trigger.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/iio/events.h>
#include <linux/delay.h>
#define MMA8452_STATUS 0x00
#define MMA8452_OUT_X 0x01 /* MSB first, 12-bit */
#define MMA8452_OUT_Y 0x03
#define MMA8452_OUT_Z 0x05
#define MMA8452_INT_SRC 0x0c
#define MMA8452_WHO_AM_I 0x0d
#define MMA8452_DATA_CFG 0x0e
#define MMA8452_HP_FILTER_CUTOFF 0x0f
#define MMA8452_HP_FILTER_CUTOFF_SEL_MASK (BIT(0) | BIT(1))
#define MMA8452_TRANSIENT_CFG 0x1d
#define MMA8452_TRANSIENT_CFG_ELE BIT(4)
#define MMA8452_TRANSIENT_CFG_CHAN(chan) BIT(chan + 1)
#define MMA8452_TRANSIENT_CFG_HPF_BYP BIT(0)
#define MMA8452_TRANSIENT_SRC 0x1e
#define MMA8452_TRANSIENT_SRC_XTRANSE BIT(1)
#define MMA8452_TRANSIENT_SRC_YTRANSE BIT(3)
#define MMA8452_TRANSIENT_SRC_ZTRANSE BIT(5)
#define MMA8452_TRANSIENT_THS 0x1f
#define MMA8452_TRANSIENT_THS_MASK 0x7f
#define MMA8452_TRANSIENT_COUNT 0x20
#define MMA8452_OFF_X 0x2f
#define MMA8452_OFF_Y 0x30
#define MMA8452_OFF_Z 0x31
#define MMA8452_CTRL_REG1 0x2a
#define MMA8452_CTRL_REG2 0x2b
#define MMA8452_CTRL_REG2_RST BIT(6)
#define MMA8452_CTRL_REG4 0x2d
#define MMA8452_CTRL_REG5 0x2e
#define MMA8452_MAX_REG 0x31
#define MMA8452_STATUS_DRDY (BIT(2) | BIT(1) | BIT(0))
#define MMA8452_CTRL_DR_MASK (BIT(5) | BIT(4) | BIT(3))
#define MMA8452_CTRL_DR_SHIFT 3
#define MMA8452_CTRL_DR_DEFAULT 0x4 /* 50 Hz sample frequency */
#define MMA8452_CTRL_ACTIVE BIT(0)
#define MMA8452_DATA_CFG_FS_MASK (BIT(1) | BIT(0))
#define MMA8452_DATA_CFG_FS_2G 0
#define MMA8452_DATA_CFG_FS_4G 1
#define MMA8452_DATA_CFG_FS_8G 2
#define MMA8452_DATA_CFG_HPF_MASK BIT(4)
#define MMA8452_INT_DRDY BIT(0)
#define MMA8452_INT_TRANS BIT(5)
#define MMA8452_DEVICE_ID 0x2a
struct mma8452_data {
struct i2c_client *client;
struct mutex lock;
u8 ctrl_reg1;
u8 data_cfg;
};
static int mma8452_drdy(struct mma8452_data *data)
{
int tries = 150;
while (tries-- > 0) {
int ret = i2c_smbus_read_byte_data(data->client,
MMA8452_STATUS);
if (ret < 0)
return ret;
if ((ret & MMA8452_STATUS_DRDY) == MMA8452_STATUS_DRDY)
return 0;
msleep(20);
}
dev_err(&data->client->dev, "data not ready\n");
return -EIO;
}
static int mma8452_read(struct mma8452_data *data, __be16 buf[3])
{
int ret = mma8452_drdy(data);
if (ret < 0)
return ret;
return i2c_smbus_read_i2c_block_data(data->client,
MMA8452_OUT_X, 3 * sizeof(__be16), (u8 *) buf);
}
static ssize_t mma8452_show_int_plus_micros(char *buf,
const int (*vals)[2], int n)
{
size_t len = 0;
while (n-- > 0)
len += scnprintf(buf + len, PAGE_SIZE - len,
"%d.%06d ", vals[n][0], vals[n][1]);
/* replace trailing space by newline */
buf[len - 1] = '\n';
return len;
}
static int mma8452_get_int_plus_micros_index(const int (*vals)[2], int n,
int val, int val2)
{
while (n-- > 0)
if (val == vals[n][0] && val2 == vals[n][1])
return n;
return -EINVAL;
}
static int mma8452_get_odr_index(struct mma8452_data *data)
{
return (data->ctrl_reg1 & MMA8452_CTRL_DR_MASK) >>
MMA8452_CTRL_DR_SHIFT;
}
static const int mma8452_samp_freq[8][2] = {
{800, 0}, {400, 0}, {200, 0}, {100, 0}, {50, 0}, {12, 500000},
{6, 250000}, {1, 560000}
};
/*
* Hardware has fullscale of -2G, -4G, -8G corresponding to raw value -2048
* The userspace interface uses m/s^2 and we declare micro units
* So scale factor is given by:
* g * N * 1000000 / 2048 for N = 2, 4, 8 and g=9.80665
*/
static const int mma8452_scales[3][2] = {
{0, 9577}, {0, 19154}, {0, 38307}
};
/* Datasheet table 35 (step time vs sample frequency) */
static const int mma8452_transient_time_step_us[8] = {
1250,
2500,
5000,
10000,
20000,
20000,
20000,
20000
};
/* Datasheet table 18 (normal mode) */
static const int mma8452_hp_filter_cutoff[8][4][2] = {
{ {16, 0}, {8, 0}, {4, 0}, {2, 0} }, /* 800 Hz sample */
{ {16, 0}, {8, 0}, {4, 0}, {2, 0} }, /* 400 Hz sample */
{ {8, 0}, {4, 0}, {2, 0}, {1, 0} }, /* 200 Hz sample */
{ {4, 0}, {2, 0}, {1, 0}, {0, 500000} }, /* 100 Hz sample */
{ {2, 0}, {1, 0}, {0, 500000}, {0, 250000} }, /* 50 Hz sample */
{ {2, 0}, {1, 0}, {0, 500000}, {0, 250000} }, /* 12.5 Hz sample */
{ {2, 0}, {1, 0}, {0, 500000}, {0, 250000} }, /* 6.25 Hz sample */
{ {2, 0}, {1, 0}, {0, 500000}, {0, 250000} } /* 1.56 Hz sample */
};
static ssize_t mma8452_show_samp_freq_avail(struct device *dev,
struct device_attribute *attr, char *buf)
{
return mma8452_show_int_plus_micros(buf, mma8452_samp_freq,
ARRAY_SIZE(mma8452_samp_freq));
}
static ssize_t mma8452_show_scale_avail(struct device *dev,
struct device_attribute *attr, char *buf)
{
return mma8452_show_int_plus_micros(buf, mma8452_scales,
ARRAY_SIZE(mma8452_scales));
}
static ssize_t mma8452_show_hp_cutoff_avail(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct mma8452_data *data = iio_priv(indio_dev);
int i = mma8452_get_odr_index(data);
return mma8452_show_int_plus_micros(buf, mma8452_hp_filter_cutoff[i],
ARRAY_SIZE(mma8452_hp_filter_cutoff[0]));
}
static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(mma8452_show_samp_freq_avail);
static IIO_DEVICE_ATTR(in_accel_scale_available, S_IRUGO,
mma8452_show_scale_avail, NULL, 0);
static IIO_DEVICE_ATTR(in_accel_filter_high_pass_3db_frequency_available,
S_IRUGO, mma8452_show_hp_cutoff_avail, NULL, 0);
static int mma8452_get_samp_freq_index(struct mma8452_data *data,
int val, int val2)
{
return mma8452_get_int_plus_micros_index(mma8452_samp_freq,
ARRAY_SIZE(mma8452_samp_freq), val, val2);
}
static int mma8452_get_scale_index(struct mma8452_data *data,
int val, int val2)
{
return mma8452_get_int_plus_micros_index(mma8452_scales,
ARRAY_SIZE(mma8452_scales), val, val2);
}
static int mma8452_get_hp_filter_index(struct mma8452_data *data,
int val, int val2)
{
int i = mma8452_get_odr_index(data);
return mma8452_get_int_plus_micros_index(mma8452_hp_filter_cutoff[i],
ARRAY_SIZE(mma8452_scales[0]), val, val2);
}
static int mma8452_read_hp_filter(struct mma8452_data *data, int *hz, int *uHz)
{
int i, ret;
ret = i2c_smbus_read_byte_data(data->client, MMA8452_HP_FILTER_CUTOFF);
if (ret < 0)
return ret;
i = mma8452_get_odr_index(data);
ret &= MMA8452_HP_FILTER_CUTOFF_SEL_MASK;
*hz = mma8452_hp_filter_cutoff[i][ret][0];
*uHz = mma8452_hp_filter_cutoff[i][ret][1];
return 0;
}
static int mma8452_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct mma8452_data *data = iio_priv(indio_dev);
__be16 buffer[3];
int i, ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
if (iio_buffer_enabled(indio_dev))
return -EBUSY;
mutex_lock(&data->lock);
ret = mma8452_read(data, buffer);
mutex_unlock(&data->lock);
if (ret < 0)
return ret;
*val = sign_extend32(
be16_to_cpu(buffer[chan->scan_index]) >> 4, 11);
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
i = data->data_cfg & MMA8452_DATA_CFG_FS_MASK;
*val = mma8452_scales[i][0];
*val2 = mma8452_scales[i][1];
return IIO_VAL_INT_PLUS_MICRO;
case IIO_CHAN_INFO_SAMP_FREQ:
i = mma8452_get_odr_index(data);
*val = mma8452_samp_freq[i][0];
*val2 = mma8452_samp_freq[i][1];
return IIO_VAL_INT_PLUS_MICRO;
case IIO_CHAN_INFO_CALIBBIAS:
ret = i2c_smbus_read_byte_data(data->client, MMA8452_OFF_X +
chan->scan_index);
if (ret < 0)
return ret;
*val = sign_extend32(ret, 7);
return IIO_VAL_INT;
case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
if (data->data_cfg & MMA8452_DATA_CFG_HPF_MASK) {
ret = mma8452_read_hp_filter(data, val, val2);
if (ret < 0)
return ret;
} else {
*val = 0;
*val2 = 0;
}
return IIO_VAL_INT_PLUS_MICRO;
}
return -EINVAL;
}
static int mma8452_standby(struct mma8452_data *data)
{
return i2c_smbus_write_byte_data(data->client, MMA8452_CTRL_REG1,
data->ctrl_reg1 & ~MMA8452_CTRL_ACTIVE);
}
static int mma8452_active(struct mma8452_data *data)
{
return i2c_smbus_write_byte_data(data->client, MMA8452_CTRL_REG1,
data->ctrl_reg1);
}
static int mma8452_change_config(struct mma8452_data *data, u8 reg, u8 val)
{
int ret;
mutex_lock(&data->lock);
/* config can only be changed when in standby */
ret = mma8452_standby(data);
if (ret < 0)
goto fail;
ret = i2c_smbus_write_byte_data(data->client, reg, val);
if (ret < 0)
goto fail;
ret = mma8452_active(data);
if (ret < 0)
goto fail;
ret = 0;
fail:
mutex_unlock(&data->lock);
return ret;
}
static int mma8452_set_hp_filter_frequency(struct mma8452_data *data,
int val, int val2)
{
int i, reg;
i = mma8452_get_hp_filter_index(data, val, val2);
if (i < 0)
return -EINVAL;
reg = i2c_smbus_read_byte_data(data->client,
MMA8452_HP_FILTER_CUTOFF);
if (reg < 0)
return reg;
reg &= ~MMA8452_HP_FILTER_CUTOFF_SEL_MASK;
reg |= i;
return mma8452_change_config(data, MMA8452_HP_FILTER_CUTOFF, reg);
}
static int mma8452_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct mma8452_data *data = iio_priv(indio_dev);
int i, ret;
if (iio_buffer_enabled(indio_dev))
return -EBUSY;
switch (mask) {
case IIO_CHAN_INFO_SAMP_FREQ:
i = mma8452_get_samp_freq_index(data, val, val2);
if (i < 0)
return -EINVAL;
data->ctrl_reg1 &= ~MMA8452_CTRL_DR_MASK;
data->ctrl_reg1 |= i << MMA8452_CTRL_DR_SHIFT;
return mma8452_change_config(data, MMA8452_CTRL_REG1,
data->ctrl_reg1);
case IIO_CHAN_INFO_SCALE:
i = mma8452_get_scale_index(data, val, val2);
if (i < 0)
return -EINVAL;
data->data_cfg &= ~MMA8452_DATA_CFG_FS_MASK;
data->data_cfg |= i;
return mma8452_change_config(data, MMA8452_DATA_CFG,
data->data_cfg);
case IIO_CHAN_INFO_CALIBBIAS:
if (val < -128 || val > 127)
return -EINVAL;
return mma8452_change_config(data, MMA8452_OFF_X +
chan->scan_index, val);
case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
if (val == 0 && val2 == 0) {
data->data_cfg &= ~MMA8452_DATA_CFG_HPF_MASK;
} else {
data->data_cfg |= MMA8452_DATA_CFG_HPF_MASK;
ret = mma8452_set_hp_filter_frequency(data, val, val2);
if (ret < 0)
return ret;
}
return mma8452_change_config(data, MMA8452_DATA_CFG,
data->data_cfg);
default:
return -EINVAL;
}
}
static int mma8452_read_thresh(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
enum iio_event_type type,
enum iio_event_direction dir,
enum iio_event_info info,
int *val, int *val2)
{
struct mma8452_data *data = iio_priv(indio_dev);
int ret, us;
switch (info) {
case IIO_EV_INFO_VALUE:
ret = i2c_smbus_read_byte_data(data->client,
MMA8452_TRANSIENT_THS);
if (ret < 0)
return ret;
*val = ret & MMA8452_TRANSIENT_THS_MASK;
return IIO_VAL_INT;
case IIO_EV_INFO_PERIOD:
ret = i2c_smbus_read_byte_data(data->client,
MMA8452_TRANSIENT_COUNT);
if (ret < 0)
return ret;
us = ret * mma8452_transient_time_step_us[
mma8452_get_odr_index(data)];
*val = us / USEC_PER_SEC;
*val2 = us % USEC_PER_SEC;
return IIO_VAL_INT_PLUS_MICRO;
case IIO_EV_INFO_HIGH_PASS_FILTER_3DB:
ret = i2c_smbus_read_byte_data(data->client,
MMA8452_TRANSIENT_CFG);
if (ret < 0)
return ret;
if (ret & MMA8452_TRANSIENT_CFG_HPF_BYP) {
*val = 0;
*val2 = 0;
} else {
ret = mma8452_read_hp_filter(data, val, val2);
if (ret < 0)
return ret;
}
return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
}
static int mma8452_write_thresh(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
enum iio_event_type type,
enum iio_event_direction dir,
enum iio_event_info info,
int val, int val2)
{
struct mma8452_data *data = iio_priv(indio_dev);
int ret, reg, steps;
switch (info) {
case IIO_EV_INFO_VALUE:
return mma8452_change_config(data, MMA8452_TRANSIENT_THS,
val & MMA8452_TRANSIENT_THS_MASK);
case IIO_EV_INFO_PERIOD:
steps = (val * USEC_PER_SEC + val2) /
mma8452_transient_time_step_us[
mma8452_get_odr_index(data)];
if (steps > 0xff)
return -EINVAL;
return mma8452_change_config(data, MMA8452_TRANSIENT_COUNT,
steps);
case IIO_EV_INFO_HIGH_PASS_FILTER_3DB:
reg = i2c_smbus_read_byte_data(data->client,
MMA8452_TRANSIENT_CFG);
if (reg < 0)
return reg;
if (val == 0 && val2 == 0) {
reg |= MMA8452_TRANSIENT_CFG_HPF_BYP;
} else {
reg &= ~MMA8452_TRANSIENT_CFG_HPF_BYP;
ret = mma8452_set_hp_filter_frequency(data, val, val2);
if (ret < 0)
return ret;
}
return mma8452_change_config(data, MMA8452_TRANSIENT_CFG, reg);
default:
return -EINVAL;
}
}
static int mma8452_read_event_config(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
enum iio_event_type type,
enum iio_event_direction dir)
{
struct mma8452_data *data = iio_priv(indio_dev);
int ret;
ret = i2c_smbus_read_byte_data(data->client, MMA8452_TRANSIENT_CFG);
if (ret < 0)
return ret;
return ret & MMA8452_TRANSIENT_CFG_CHAN(chan->scan_index) ? 1 : 0;
}
static int mma8452_write_event_config(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
enum iio_event_type type,
enum iio_event_direction dir,
int state)
{
struct mma8452_data *data = iio_priv(indio_dev);
int val;
val = i2c_smbus_read_byte_data(data->client, MMA8452_TRANSIENT_CFG);
if (val < 0)
return val;
if (state)
val |= MMA8452_TRANSIENT_CFG_CHAN(chan->scan_index);
else
val &= ~MMA8452_TRANSIENT_CFG_CHAN(chan->scan_index);
val |= MMA8452_TRANSIENT_CFG_ELE;
return mma8452_change_config(data, MMA8452_TRANSIENT_CFG, val);
}
static void mma8452_transient_interrupt(struct iio_dev *indio_dev)
{
struct mma8452_data *data = iio_priv(indio_dev);
s64 ts = iio_get_time_ns();
int src;
src = i2c_smbus_read_byte_data(data->client, MMA8452_TRANSIENT_SRC);
if (src < 0)
return;
if (src & MMA8452_TRANSIENT_SRC_XTRANSE)
iio_push_event(indio_dev,
IIO_MOD_EVENT_CODE(IIO_ACCEL, 0, IIO_MOD_X,
IIO_EV_TYPE_THRESH,
IIO_EV_DIR_RISING),
ts);
if (src & MMA8452_TRANSIENT_SRC_YTRANSE)
iio_push_event(indio_dev,
IIO_MOD_EVENT_CODE(IIO_ACCEL, 0, IIO_MOD_Y,
IIO_EV_TYPE_THRESH,
IIO_EV_DIR_RISING),
ts);
if (src & MMA8452_TRANSIENT_SRC_ZTRANSE)
iio_push_event(indio_dev,
IIO_MOD_EVENT_CODE(IIO_ACCEL, 0, IIO_MOD_Z,
IIO_EV_TYPE_THRESH,
IIO_EV_DIR_RISING),
ts);
}
static irqreturn_t mma8452_interrupt(int irq, void *p)
{
struct iio_dev *indio_dev = p;
struct mma8452_data *data = iio_priv(indio_dev);
int ret = IRQ_NONE;
int src;
src = i2c_smbus_read_byte_data(data->client, MMA8452_INT_SRC);
if (src < 0)
return IRQ_NONE;
if (src & MMA8452_INT_DRDY) {
iio_trigger_poll_chained(indio_dev->trig);
ret = IRQ_HANDLED;
}
if (src & MMA8452_INT_TRANS) {
mma8452_transient_interrupt(indio_dev);
ret = IRQ_HANDLED;
}
return ret;
}
static irqreturn_t mma8452_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct mma8452_data *data = iio_priv(indio_dev);
u8 buffer[16]; /* 3 16-bit channels + padding + ts */
int ret;
ret = mma8452_read(data, (__be16 *) buffer);
if (ret < 0)
goto done;
iio_push_to_buffers_with_timestamp(indio_dev, buffer,
iio_get_time_ns());
done:
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
static int mma8452_reg_access_dbg(struct iio_dev *indio_dev,
unsigned reg, unsigned writeval,
unsigned *readval)
{
int ret;
struct mma8452_data *data = iio_priv(indio_dev);
if (reg > MMA8452_MAX_REG)
return -EINVAL;
if (!readval)
return mma8452_change_config(data, reg, writeval);
ret = i2c_smbus_read_byte_data(data->client, reg);
if (ret < 0)
return ret;
*readval = ret;
return 0;
}
static const struct iio_event_spec mma8452_transient_event[] = {
{
.type = IIO_EV_TYPE_THRESH,
.dir = IIO_EV_DIR_RISING,
.mask_separate = BIT(IIO_EV_INFO_ENABLE),
.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
BIT(IIO_EV_INFO_PERIOD) |
BIT(IIO_EV_INFO_HIGH_PASS_FILTER_3DB)
},
};
/*
* Threshold is configured in fixed 8G/127 steps regardless of
* currently selected scale for measurement.
*/
static IIO_CONST_ATTR_NAMED(accel_transient_scale, in_accel_scale, "0.617742");
static struct attribute *mma8452_event_attributes[] = {
&iio_const_attr_accel_transient_scale.dev_attr.attr,
NULL,
};
static struct attribute_group mma8452_event_attribute_group = {
.attrs = mma8452_event_attributes,
.name = "events",
};
#define MMA8452_CHANNEL(axis, idx) { \
.type = IIO_ACCEL, \
.modified = 1, \
.channel2 = IIO_MOD_##axis, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_CALIBBIAS), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
BIT(IIO_CHAN_INFO_SCALE) | \
BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY), \
.scan_index = idx, \
.scan_type = { \
.sign = 's', \
.realbits = 12, \
.storagebits = 16, \
.shift = 4, \
.endianness = IIO_BE, \
}, \
.event_spec = mma8452_transient_event, \
.num_event_specs = ARRAY_SIZE(mma8452_transient_event), \
}
static const struct iio_chan_spec mma8452_channels[] = {
MMA8452_CHANNEL(X, 0),
MMA8452_CHANNEL(Y, 1),
MMA8452_CHANNEL(Z, 2),
IIO_CHAN_SOFT_TIMESTAMP(3),
};
static struct attribute *mma8452_attributes[] = {
&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
&iio_dev_attr_in_accel_scale_available.dev_attr.attr,
&iio_dev_attr_in_accel_filter_high_pass_3db_frequency_available.dev_attr.attr,
NULL
};
static const struct attribute_group mma8452_group = {
.attrs = mma8452_attributes,
};
static const struct iio_info mma8452_info = {
.attrs = &mma8452_group,
.read_raw = &mma8452_read_raw,
.write_raw = &mma8452_write_raw,
.event_attrs = &mma8452_event_attribute_group,
.read_event_value = &mma8452_read_thresh,
.write_event_value = &mma8452_write_thresh,
.read_event_config = &mma8452_read_event_config,
.write_event_config = &mma8452_write_event_config,
.debugfs_reg_access = &mma8452_reg_access_dbg,
.driver_module = THIS_MODULE,
};
static const unsigned long mma8452_scan_masks[] = {0x7, 0};
static int mma8452_data_rdy_trigger_set_state(struct iio_trigger *trig,
bool state)
{
struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
struct mma8452_data *data = iio_priv(indio_dev);
int reg;
reg = i2c_smbus_read_byte_data(data->client, MMA8452_CTRL_REG4);
if (reg < 0)
return reg;
if (state)
reg |= MMA8452_INT_DRDY;
else
reg &= ~MMA8452_INT_DRDY;
return mma8452_change_config(data, MMA8452_CTRL_REG4, reg);
}
static int mma8452_validate_device(struct iio_trigger *trig,
struct iio_dev *indio_dev)
{
struct iio_dev *indio = iio_trigger_get_drvdata(trig);
if (indio != indio_dev)
return -EINVAL;
return 0;
}
static const struct iio_trigger_ops mma8452_trigger_ops = {
.set_trigger_state = mma8452_data_rdy_trigger_set_state,
.validate_device = mma8452_validate_device,
.owner = THIS_MODULE,
};
static int mma8452_trigger_setup(struct iio_dev *indio_dev)
{
struct mma8452_data *data = iio_priv(indio_dev);
struct iio_trigger *trig;
int ret;
trig = devm_iio_trigger_alloc(&data->client->dev, "%s-dev%d",
indio_dev->name,
indio_dev->id);
if (!trig)
return -ENOMEM;
trig->dev.parent = &data->client->dev;
trig->ops = &mma8452_trigger_ops;
iio_trigger_set_drvdata(trig, indio_dev);
ret = iio_trigger_register(trig);
if (ret)
return ret;
indio_dev->trig = trig;
return 0;
}
static void mma8452_trigger_cleanup(struct iio_dev *indio_dev)
{
if (indio_dev->trig)
iio_trigger_unregister(indio_dev->trig);
}
static int mma8452_reset(struct i2c_client *client)
{
int i;
int ret;
ret = i2c_smbus_write_byte_data(client, MMA8452_CTRL_REG2,
MMA8452_CTRL_REG2_RST);
if (ret < 0)
return ret;
for (i = 0; i < 10; i++) {
usleep_range(100, 200);
ret = i2c_smbus_read_byte_data(client, MMA8452_CTRL_REG2);
if (ret == -EIO)
continue; /* I2C comm reset */
if (ret < 0)
return ret;
if (!(ret & MMA8452_CTRL_REG2_RST))
return 0;
}
return -ETIMEDOUT;
}
static int mma8452_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct mma8452_data *data;
struct iio_dev *indio_dev;
int ret;
ret = i2c_smbus_read_byte_data(client, MMA8452_WHO_AM_I);
if (ret < 0)
return ret;
if (ret != MMA8452_DEVICE_ID)
return -ENODEV;
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
data = iio_priv(indio_dev);
data->client = client;
mutex_init(&data->lock);
i2c_set_clientdata(client, indio_dev);
indio_dev->info = &mma8452_info;
indio_dev->name = id->name;
indio_dev->dev.parent = &client->dev;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = mma8452_channels;
indio_dev->num_channels = ARRAY_SIZE(mma8452_channels);
indio_dev->available_scan_masks = mma8452_scan_masks;
ret = mma8452_reset(client);
if (ret < 0)
return ret;
data->data_cfg = MMA8452_DATA_CFG_FS_2G;
ret = i2c_smbus_write_byte_data(client, MMA8452_DATA_CFG,
data->data_cfg);
if (ret < 0)
return ret;
/*
* By default set transient threshold to max to avoid events if
* enabling without configuring threshold.
*/
ret = i2c_smbus_write_byte_data(client, MMA8452_TRANSIENT_THS,
MMA8452_TRANSIENT_THS_MASK);
if (ret < 0)
return ret;
if (client->irq) {
/*
* Although we enable the transient interrupt source once and
* for all here the transient event detection itself is not
* enabled until userspace asks for it by
* mma8452_write_event_config()
*/
int supported_interrupts = MMA8452_INT_DRDY | MMA8452_INT_TRANS;
int enabled_interrupts = MMA8452_INT_TRANS;
/* Assume wired to INT1 pin */
ret = i2c_smbus_write_byte_data(client,
MMA8452_CTRL_REG5,
supported_interrupts);
if (ret < 0)
return ret;
ret = i2c_smbus_write_byte_data(client,
MMA8452_CTRL_REG4,
enabled_interrupts);
if (ret < 0)
return ret;
ret = mma8452_trigger_setup(indio_dev);
if (ret < 0)
return ret;
}
data->ctrl_reg1 = MMA8452_CTRL_ACTIVE |
(MMA8452_CTRL_DR_DEFAULT << MMA8452_CTRL_DR_SHIFT);
ret = i2c_smbus_write_byte_data(client, MMA8452_CTRL_REG1,
data->ctrl_reg1);
if (ret < 0)
goto trigger_cleanup;
ret = iio_triggered_buffer_setup(indio_dev, NULL,
mma8452_trigger_handler, NULL);
if (ret < 0)
goto trigger_cleanup;
if (client->irq) {
ret = devm_request_threaded_irq(&client->dev,
client->irq,
NULL, mma8452_interrupt,
IRQF_TRIGGER_LOW | IRQF_ONESHOT,
client->name, indio_dev);
if (ret)
goto buffer_cleanup;
}
ret = iio_device_register(indio_dev);
if (ret < 0)
goto buffer_cleanup;
return 0;
buffer_cleanup:
iio_triggered_buffer_cleanup(indio_dev);
trigger_cleanup:
mma8452_trigger_cleanup(indio_dev);
return ret;
}
static int mma8452_remove(struct i2c_client *client)
{
struct iio_dev *indio_dev = i2c_get_clientdata(client);
iio_device_unregister(indio_dev);
iio_triggered_buffer_cleanup(indio_dev);
mma8452_trigger_cleanup(indio_dev);
mma8452_standby(iio_priv(indio_dev));
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int mma8452_suspend(struct device *dev)
{
return mma8452_standby(iio_priv(i2c_get_clientdata(
to_i2c_client(dev))));
}
static int mma8452_resume(struct device *dev)
{
return mma8452_active(iio_priv(i2c_get_clientdata(
to_i2c_client(dev))));
}
static SIMPLE_DEV_PM_OPS(mma8452_pm_ops, mma8452_suspend, mma8452_resume);
#define MMA8452_PM_OPS (&mma8452_pm_ops)
#else
#define MMA8452_PM_OPS NULL
#endif
static const struct i2c_device_id mma8452_id[] = {
{ "mma8452", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, mma8452_id);
static const struct of_device_id mma8452_dt_ids[] = {
{ .compatible = "fsl,mma8452" },
{ }
};
MODULE_DEVICE_TABLE(of, mma8452_dt_ids);
static struct i2c_driver mma8452_driver = {
.driver = {
.name = "mma8452",
.of_match_table = of_match_ptr(mma8452_dt_ids),
.pm = MMA8452_PM_OPS,
},
.probe = mma8452_probe,
.remove = mma8452_remove,
.id_table = mma8452_id,
};
module_i2c_driver(mma8452_driver);
MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
MODULE_DESCRIPTION("Freescale MMA8452 accelerometer driver");
MODULE_LICENSE("GPL");
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