[PATCH v4 06/10] iio: adc: adi-axi-adc: add data align process

From: Antoniu Miclaus
Date: Fri May 02 2025 - 05:00:56 EST


Add support for starting the sync process used for data
capture alignment.

Signed-off-by: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx>
---
changes in v4:
- rework data_align function.
- rename bit definitions/functions.
drivers/iio/adc/adi-axi-adc.c | 37 +++++++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)

diff --git a/drivers/iio/adc/adi-axi-adc.c b/drivers/iio/adc/adi-axi-adc.c
index 2a3a6c3f5e59..2a79c043c0de 100644
--- a/drivers/iio/adc/adi-axi-adc.c
+++ b/drivers/iio/adc/adi-axi-adc.c
@@ -44,6 +44,7 @@
#define ADI_AXI_ADC_REG_CONFIG_CMOS_OR_LVDS_N BIT(7)

#define ADI_AXI_ADC_REG_CTRL 0x0044
+#define ADI_AXI_ADC_CTRL_SYNC_MSK BIT(3)
#define ADI_AXI_ADC_CTRL_DDR_EDGESEL_MASK BIT(1)

#define ADI_AXI_ADC_REG_CNTRL_3 0x004c
@@ -54,6 +55,9 @@
#define AXI_AD485X_PACKET_FORMAT_32BIT 0x2
#define AXI_AD408X_CNTRL_3_FILTER_EN_MSK BIT(0)

+#define ADI_AXI_ADC_REG_SYNC_STATUS 0x0068
+#define ADI_AXI_ADC_SYNC_STATUS_ADC_SYNC_MSK BIT(0)
+
#define ADI_AXI_ADC_REG_DRP_STATUS 0x0074
#define ADI_AXI_ADC_DRP_LOCKED BIT(17)

@@ -416,6 +420,38 @@ static int axi_adc_ad408x_filter_type_set(struct iio_backend *back,
AXI_AD408X_CNTRL_3_FILTER_EN_MSK);
}

+static int axi_adc_ad408x_interface_data_align(struct iio_backend *back,
+ u32 timeout)
+{
+ struct adi_axi_adc_state *st = iio_backend_get_priv(back);
+ bool sync_en;
+ u32 val;
+ int ret;
+
+ ret = regmap_set_bits(st->regmap, ADI_AXI_ADC_REG_CTRL,
+ ADI_AXI_ADC_CTRL_SYNC_MSK);
+ if (ret)
+ return ret;
+
+ do {
+ ret = regmap_read(st->regmap, ADI_AXI_ADC_REG_SYNC_STATUS, &val);
+ if (ret)
+ return ret;
+
+ sync_en = FIELD_GET(ADI_AXI_ADC_SYNC_STATUS_ADC_SYNC_MSK, val);
+
+ if (!sync_en)
+ dev_dbg(st->dev, "Not Locked: Running Bit Slip\n");
+
+ fsleep(500);
+ } while (--timeout && !sync_en);
+
+ if (!timeout)
+ return -ETIMEDOUT;
+
+ return 0;
+}
+
static struct iio_buffer *axi_adc_request_buffer(struct iio_backend *back,
struct iio_dev *indio_dev)
{
@@ -605,6 +641,7 @@ static const struct iio_backend_ops adi_ad408x_ops = {
.free_buffer = axi_adc_free_buffer,
.data_sample_trigger = axi_adc_data_sample_trigger,
.filter_type_set = axi_adc_ad408x_filter_type_set,
+ .interface_data_align = axi_adc_ad408x_interface_data_align,
.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),
};
--
2.49.0