[PATCH 9/9] iio: adc: ad7173: add SPI offload support

From: David Lechner
Date: Fri Jun 20 2025 - 18:29:59 EST


Enable SPI offload support for the AD7173 ADC driver.

The scan_type used for SPI offload is assuming that we are using the
ad411x_ad717x HDL project [1] which always stores data words in 32-bits.

Link: https://analogdevicesinc.github.io/hdl/projects/ad411x_ad717x/index.html [1]
Signed-off-by: David Lechner <dlechner@xxxxxxxxxxxx>
---
drivers/iio/adc/ad7173.c | 13 +++++++++++++
1 file changed, 13 insertions(+)

diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
index 010339c2b7044da4b36dc894a38a145c2fcccd6a..580d4bf3366b193fa0f13d0a28886d390e1295b8 100644
--- a/drivers/iio/adc/ad7173.c
+++ b/drivers/iio/adc/ad7173.c
@@ -748,6 +748,7 @@ static const struct ad_sigma_delta_info ad7173_sigma_delta_info_4_slots = {
.set_mode = ad7173_set_mode,
.has_registers = true,
.has_named_irqs = true,
+ .supports_spi_offload = true,
.addr_shift = 0,
.read_mask = BIT(6),
.status_ch_mask = GENMASK(3, 0),
@@ -764,6 +765,7 @@ static const struct ad_sigma_delta_info ad7173_sigma_delta_info_8_slots = {
.set_mode = ad7173_set_mode,
.has_registers = true,
.has_named_irqs = true,
+ .supports_spi_offload = true,
.addr_shift = 0,
.read_mask = BIT(6),
.status_ch_mask = GENMASK(3, 0),
@@ -1585,6 +1587,11 @@ static int ad7173_fw_parse_channel_config(struct iio_dev *indio_dev)
if (st->info->data_reg_only_16bit)
chan_arr[chan_index].scan_type = ad4113_scan_type;

+ if (ad_sigma_delta_has_spi_offload(&st->sd)) {
+ chan_arr[chan_index].scan_type.storagebits = 32;
+ chan_arr[chan_index].scan_type.endianness = IIO_CPU;
+ }
+
chan_index++;
}

@@ -1675,6 +1682,12 @@ static int ad7173_fw_parse_channel_config(struct iio_dev *indio_dev)
if (st->info->data_reg_only_16bit)
chan_arr[chan_index].scan_type = ad4113_scan_type;

+ /* Assuming SPI offload is ad411x_ad717x HDL project. */
+ if (ad_sigma_delta_has_spi_offload(&st->sd)) {
+ chan_arr[chan_index].scan_type.storagebits = 32;
+ chan_arr[chan_index].scan_type.endianness = IIO_CPU;
+ }
+
chan_index++;
}
return 0;

--
2.43.0