[PATCH v4 04/14] iio: adc: adi-axi-adc: Add support for CRC

[Janani Sunil <janani.sunil@analog.com>]

Add support for enabling and disabling Cyclic Redundancy Check (CRC)
processing in the AXI ADC backend. CRC provides data integrity verification
for high-speed ADC data streams, ensuring reliable data transfer between
the ADC frontend and backend processing systems.

Signed-off-by: Janani Sunil <janani.sunil@analog.com>
---
 drivers/iio/adc/adi-axi-adc.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/drivers/iio/adc/adi-axi-adc.c b/drivers/iio/adc/adi-axi-adc.c
index b5e59b1871b6..e8f149e230e7 100644
--- a/drivers/iio/adc/adi-axi-adc.c
+++ b/drivers/iio/adc/adi-axi-adc.c
@@ -47,6 +47,9 @@
 #define    ADI_AXI_ADC_CTRL_DDR_EDGESEL_MASK	BIT(1)
 
 #define ADI_AXI_ADC_REG_CNTRL_3			0x004c
+/* Bit 8 is common to all AXI ADC cores; bits 7-0 are per-HDL-project. */
+#define    ADI_AXI_ADC_CNTRL_3_CRC_EN_MASK	BIT(8)
+
 #define   AXI_AD485X_CNTRL_3_OS_EN_MSK		BIT(2)
 #define   AXI_AD485X_CNTRL_3_PACKET_FORMAT_MSK	GENMASK(1, 0)
 #define   AXI_AD485X_PACKET_FORMAT_20BIT	0x0
@@ -567,6 +570,22 @@ static int axi_adc_reg_access(struct iio_backend *back, unsigned int reg,
 	return regmap_write(st->regmap, reg, writeval);
 }
 
+static int axi_adc_crc_enable(struct iio_backend *back)
+{
+	struct adi_axi_adc_state *st = iio_backend_get_priv(back);
+
+	return regmap_set_bits(st->regmap, ADI_AXI_ADC_REG_CNTRL_3,
+			       ADI_AXI_ADC_CNTRL_3_CRC_EN_MASK);
+}
+
+static int axi_adc_crc_disable(struct iio_backend *back)
+{
+	struct adi_axi_adc_state *st = iio_backend_get_priv(back);
+
+	return regmap_clear_bits(st->regmap, ADI_AXI_ADC_REG_CNTRL_3,
+				 ADI_AXI_ADC_CNTRL_3_CRC_EN_MASK);
+}
+
 static const struct regmap_config axi_adc_regmap_config = {
 	.val_bits = 32,
 	.reg_bits = 32,
@@ -615,6 +634,8 @@ static const struct iio_backend_ops adi_axi_adc_ops = {
 	.num_lanes_set = axi_adc_num_lanes_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),
+	.crc_enable = axi_adc_crc_enable,
+	.crc_disable = axi_adc_crc_disable,
 };
 
 static const struct iio_backend_info adi_axi_adc_generic = {

-- 
2.43.0