[PATCH v12 7/9] iio: adc: adi-axi-adc: add oversampling

Antoniu Miclaus
2025-02-07T14:10:02Z

Add support for enabling/disabling oversampling.

Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
---
no changes in v12.
drivers/iio/adc/adi-axi-adc.c | 24 ++++++++++++++++++++++++
1 file changed, 24 insertions(+)

diff --git a/drivers/iio/adc/adi-axi-adc.c b/drivers/iio/adc/adi-axi-adc.c
index 272d82c6e887..872ff51e08a7 100644
--- a/drivers/iio/adc/adi-axi-adc.c
+++ b/drivers/iio/adc/adi-axi-adc.c
@@ -46,6 +46,7 @@
#define ADI_AXI_ADC_CTRL_DDR_EDGESEL_MASK BIT(1)

#define ADI_AXI_ADC_REG_CNTRL_3 0x004c
+#define AD485X_CNTRL_3_OS_EN_MSK BIT(2)
#define AD485X_CNTRL_3_PACKET_FORMAT_MSK GENMASK(1, 0)
#define AD485X_PACKET_FORMAT_20BIT 0x0
#define AD485X_PACKET_FORMAT_24BIT 0x1
@@ -363,6 +364,28 @@ static int axi_adc_data_size_set(struct iio_backend *back, unsigned int size)
FIELD_PREP(AD485X_CNTRL_3_PACKET_FORMAT_MSK, val));
}

+static int axi_adc_oversampling_ratio_set(struct iio_backend *back,
+ unsigned int ratio)
+{
+ struct adi_axi_adc_state *st = iio_backend_get_priv(back);
+
+ /* The current state of the function enables or disables the
+ * oversampling in REG_CNTRL_3 register. A ratio equal to 1 implies no
+ * oversampling, while a value greater than 1 implies oversampling being
+ * enabled.
+ */
+ switch (ratio) {
+ case 0:
+ return -EINVAL;
+ case 1:
+ return regmap_clear_bits(st->regmap, ADI_AXI_ADC_REG_CNTRL_3,
+ AD485X_CNTRL_3_OS_EN_MSK);
+ default:
+ return regmap_set_bits(st->regmap, ADI_AXI_ADC_REG_CNTRL_3,
+ AD485X_CNTRL_3_OS_EN_MSK);
+ }
+}
+
static struct iio_buffer *axi_adc_request_buffer(struct iio_backend *back,
struct iio_dev *indio_dev)
{
@@ -428,6 +451,7 @@ static const struct iio_backend_ops adi_ad485x_ops = {
.chan_status = axi_adc_chan_status,
.interface_type_get = axi_adc_interface_type_get,
.data_size_set = axi_adc_data_size_set,
+ .oversampling_ratio_set = axi_adc_oversampling_ratio_set,
.debugfs_reg_access = iio_backend_debugfs_ptr(axi_adc_reg_access),
.debugfs_print_chan_status = iio_backend_debugfs_ptr(axi_adc_debugfs_print_chan_status),
};
--
2.48.1