Re: [PATCH v3 07/10] iio: adc: adi-axi-adc: add support for AD7606 register writing

+static int ad7606_bus_reg_read(struct iio_backend *back, u32 reg, u32 *val)
+{
+	struct adi_axi_adc_state *st = iio_backend_get_priv(back);
+	u32 buf;
+
+	guard(mutex)(&st->lock);
+
+	/*
+	 * The address is written on the highest weight byte, and the MSB set
+	 * at 1 indicates a read operation.
+	 */
+	buf = FIELD_PREP(ADI_AXI_REG_ADDRESS_MASK, reg) | ADI_AXI_REG_READ_BIT;
+	axi_adc_raw_write(back, &buf, sizeof(buf));
+	axi_adc_raw_read(back, val, 4);

+
+	/* Write 0x0 on the bus to get back to ADC mode */
+	buf = 0;
+	axi_adc_raw_write(back, &buf, sizeof(buf));
+	return 0;
+}