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

[Antoniu Miclaus <antoniu.miclaus@analog.com>]

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

Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
---
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