This patch adds support for buffered readings for the 3-axis
accelerometer mxc4005.
Signed-off-by: Teodora Baluta <teodora.baluta@xxxxxxxxx>
---
drivers/iio/accel/Kconfig | 2 ++
drivers/iio/accel/mxc4005.c | 75 +++++++++++++++++++++++++++++++++++++++++++--
2 files changed, 75 insertions(+), 2 deletions(-)
diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index 69302be..cd5cd24 100644
--- a/drivers/iio/accel/Kconfig
+++ b/drivers/iio/accel/Kconfig
@@ -140,6 +140,8 @@ config MMA9553
config MXC4005
tristate "Memsic MXC4005XC 3-Axis Accelerometer Driver"
depends on I2C
+ select IIO_BUFFER
+ select IIO_TRIGGERED_BUFFER
select REGMAP_I2C
help
Say yes here to build support for the Memsic MXC4005XC 3-axis
diff --git a/drivers/iio/accel/mxc4005.c b/drivers/iio/accel/mxc4005.c
index 76a7954..5f4813d 100644
--- a/drivers/iio/accel/mxc4005.c
+++ b/drivers/iio/accel/mxc4005.c
@@ -19,6 +19,9 @@
#include <linux/acpi.h>
#include <linux/regmap.h>
#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
#define MXC4005_DRV_NAME "mxc4005"
#define MXC4005_REGMAP_NAME "mxc4005_regmap"
@@ -52,6 +55,7 @@ struct mxc4005_data {
struct i2c_client *client;
struct mutex mutex;
struct regmap *regmap;
+ __be16 buffer[3];
};
/*
@@ -123,6 +127,20 @@ static const struct regmap_config mxc4005_regmap_config = {
.writeable_reg = mxc4005_is_writeable_reg,
};
+static int mxc4005_read_xyz(struct mxc4005_data *data)
+{
+ int ret;
+
+ ret = regmap_bulk_read(data->regmap, MXC4005_REG_XOUT_UPPER,
+ (u8 *) data->buffer, sizeof(data->buffer));
+ if (ret < 0) {
+ dev_err(&data->client->dev, "failed to read axes\n");
+ return ret;
+ }
+
+ return 0;
+}
+
static int mxc4005_read_axis(struct mxc4005_data *data,
unsigned int addr)
{
@@ -198,7 +216,8 @@ static int mxc4005_read_raw(struct iio_dev *indio_dev,
ret = mxc4005_read_axis(data, chan->address);
if (ret < 0)
return ret;
- *val = sign_extend32(ret >> 4, 11);
+ *val = sign_extend32(ret >> chan->scan_type.shift,
+ chan->scan_type.realbits - 1);
return IIO_VAL_INT;
default:
return -EINVAL;
@@ -240,6 +259,11 @@ static const struct iio_info mxc4005_info = {
.attrs = &mxc4005_attrs_group,
};
+static const unsigned long mxc4005_scan_masks[] = {
+ BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z),
+ 0
+};
+
#define MXC4005_CHANNEL(_axis, _addr) { \
.type = IIO_ACCEL, \
.modified = 1, \
@@ -247,14 +271,43 @@ static const struct iio_info mxc4005_info = {
.address = _addr, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+ .scan_index = AXIS_##_axis, \
+ .scan_type = { \
+ .sign = 's', \
+ .realbits = 12, \
+ .storagebits = 16, \
+ .shift = 4, \
+ .endianness = IIO_BE, \
+ }, \
}
static const struct iio_chan_spec mxc4005_channels[] = {
MXC4005_CHANNEL(X, MXC4005_REG_XOUT_UPPER),
MXC4005_CHANNEL(Y, MXC4005_REG_YOUT_UPPER),
MXC4005_CHANNEL(Z, MXC4005_REG_ZOUT_UPPER),
+ IIO_CHAN_SOFT_TIMESTAMP(3),
};
+static irqreturn_t mxc4005_trigger_handler(int irq, void *private)
+{
+ struct iio_poll_func *pf = private;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct mxc4005_data *data = iio_priv(indio_dev);
+ int ret;
+
+ ret = mxc4005_read_xyz(data);
+ if (ret < 0)
+ goto err;
+
+ iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
+ iio_get_time_ns());
+
+err:
+ iio_trigger_notify_done(indio_dev->trig);
+
+ return IRQ_HANDLED;
+}
+
static int mxc4005_chip_init(struct mxc4005_data *data)
{
int ret;
@@ -305,18 +358,34 @@ static int mxc4005_probe(struct i2c_client *client,
indio_dev->dev.parent = &client->dev;
indio_dev->channels = mxc4005_channels;
indio_dev->num_channels = ARRAY_SIZE(mxc4005_channels);
+ indio_dev->available_scan_masks = mxc4005_scan_masks;
indio_dev->name = MXC4005_DRV_NAME;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->info = &mxc4005_info;
+ ret = iio_triggered_buffer_setup(indio_dev,
+ &iio_pollfunc_store_time,
+ mxc4005_trigger_handler,
+ NULL);
+ if (ret < 0) {
+ dev_err(&client->dev,
+ "failed to setup iio triggered buffer\n");
+ return ret;
+ }
+
ret = iio_device_register(indio_dev);
if (ret < 0) {
dev_err(&client->dev,
"unable to register iio device %d\n", ret);
- return ret;
+ goto err_buffer_cleanup;
}
return 0;
+
+err_buffer_cleanup:
+ iio_triggered_buffer_cleanup(indio_dev);
+
+ return ret;
}
static int mxc4005_remove(struct i2c_client *client)
@@ -325,6 +394,8 @@ static int mxc4005_remove(struct i2c_client *client)
iio_device_unregister(indio_dev);
+ iio_triggered_buffer_cleanup(indio_dev);
+
return 0;
}
--
1.9.1
--
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