[PATCH v4 02/11] iio: accel: adxl313: introduce channel buffer

From: Lothar Rubusch
Date: Sun Jun 01 2025 - 13:22:23 EST


Add a scan_mask and scan_index to the iio channel. The scan_index
prepares the buffer usage. According to the datasheet, the ADXL313
uses 13 bit in full resolution. Add signedness, storage bits and
endianness.

Signed-off-by: Lothar Rubusch <l.rubusch@xxxxxxxxx>
---
drivers/iio/accel/adxl313_core.c | 24 +++++++++++++++++++-----
1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/drivers/iio/accel/adxl313_core.c b/drivers/iio/accel/adxl313_core.c
index 2f26da5857d4..06a771bb4726 100644
--- a/drivers/iio/accel/adxl313_core.c
+++ b/drivers/iio/accel/adxl313_core.c
@@ -171,9 +171,10 @@ static const int adxl313_odr_freqs[][2] = {
[9] = { 3200, 0 },
};

-#define ADXL313_ACCEL_CHANNEL(index, axis) { \
+#define ADXL313_ACCEL_CHANNEL(index, reg, axis) { \
.type = IIO_ACCEL, \
- .address = index, \
+ .scan_index = (index), \
+ .address = (reg), \
.modified = 1, \
.channel2 = IIO_MOD_##axis, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
@@ -183,14 +184,26 @@ static const int adxl313_odr_freqs[][2] = {
.info_mask_shared_by_type_available = \
BIT(IIO_CHAN_INFO_SAMP_FREQ), \
.scan_type = { \
+ .sign = 's', \
.realbits = 13, \
+ .storagebits = 16, \
+ .endianness = IIO_BE, \
}, \
}

+enum adxl313_chans {
+ chan_x, chan_y, chan_z,
+};
+
static const struct iio_chan_spec adxl313_channels[] = {
- ADXL313_ACCEL_CHANNEL(0, X),
- ADXL313_ACCEL_CHANNEL(1, Y),
- ADXL313_ACCEL_CHANNEL(2, Z),
+ ADXL313_ACCEL_CHANNEL(0, chan_x, X),
+ ADXL313_ACCEL_CHANNEL(1, chan_y, Y),
+ ADXL313_ACCEL_CHANNEL(2, chan_z, Z),
+};
+
+static const unsigned long adxl313_scan_masks[] = {
+ BIT(chan_x) | BIT(chan_y) | BIT(chan_z),
+ 0
};

static int adxl313_set_odr(struct adxl313_data *data,
@@ -419,6 +432,7 @@ int adxl313_core_probe(struct device *dev,
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = adxl313_channels;
indio_dev->num_channels = ARRAY_SIZE(adxl313_channels);
+ indio_dev->available_scan_masks = adxl313_scan_masks;

ret = adxl313_setup(dev, data, setup);
if (ret) {
--
2.39.5