iio: adc: adi-axi-adc: set data format

Add support for selecting the data format within the AXI ADC ip.

Add separate complatible string for the custom AD485X IP and implement
the necessary changes.

Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
Link: https://patch.msgid.link/20250214131955.31973-7-antoniu.miclaus@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/adc/adi-axi-adc.c b/drivers/iio/adc/adi-axi-adc.c
index fb3ff605db05dd9013c75c6881c81f8aa347be3d..ed6a46bdbd8088f498f41815ec15807352373935 100644 (file)
--- a/drivers/iio/adc/adi-axi-adc.c
+++ b/drivers/iio/adc/adi-axi-adc.c
@@ -46,6 +46,12 @@
 #define ADI_AXI_ADC_REG_CTRL                   0x0044
 #define    ADI_AXI_ADC_CTRL_DDR_EDGESEL_MASK   BIT(1)
 
+#define ADI_AXI_ADC_REG_CNTRL_3                        0x004c
+#define   AXI_AD485X_CNTRL_3_PACKET_FORMAT_MSK GENMASK(1, 0)
+#define   AXI_AD485X_PACKET_FORMAT_20BIT       0x0
+#define   AXI_AD485X_PACKET_FORMAT_24BIT       0x1
+#define   AXI_AD485X_PACKET_FORMAT_32BIT       0x2
+
 #define ADI_AXI_ADC_REG_DRP_STATUS             0x0074
 #define   ADI_AXI_ADC_DRP_LOCKED               BIT(17)
 
@@ -332,6 +338,47 @@ static int axi_adc_interface_type_get(struct iio_backend *back,
        return 0;
 }
 
+static int axi_adc_ad485x_data_size_set(struct iio_backend *back,
+                                       unsigned int size)
+{
+       struct adi_axi_adc_state *st = iio_backend_get_priv(back);
+       unsigned int val;
+
+       switch (size) {
+       /*
+        * There are two different variants of the AXI AXI_AD485X IP block, a
+        * 16-bit and a 20-bit variant.
+        * The 0x0 value (AXI_AD485X_PACKET_FORMAT_20BIT) is corresponding also
+        * to the 16-bit variant of the IP block.
+        */
+       case 16:
+       case 20:
+               val = AXI_AD485X_PACKET_FORMAT_20BIT;
+               break;
+       case 24:
+               val = AXI_AD485X_PACKET_FORMAT_24BIT;
+               break;
+       /*
+        * The 0x2 (AXI_AD485X_PACKET_FORMAT_32BIT) corresponds only to the
+        * 20-bit variant of the IP block. Setting this value properly is
+        * ensured by the upper layers of the drivers calling the axi-adc
+        * functions.
+        * Also, for 16-bit IP block, the 0x2 (AXI_AD485X_PACKET_FORMAT_32BIT)
+        * value is handled as maximum size available which is 24-bit for this
+        * configuration.
+        */
+       case 32:
+               val = AXI_AD485X_PACKET_FORMAT_32BIT;
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       return regmap_update_bits(st->regmap, ADI_AXI_ADC_REG_CNTRL_3,
+                                 AXI_AD485X_CNTRL_3_PACKET_FORMAT_MSK,
+                                 FIELD_PREP(AXI_AD485X_CNTRL_3_PACKET_FORMAT_MSK, val));
+}
+
 static struct iio_buffer *axi_adc_request_buffer(struct iio_backend *back,
                                                 struct iio_dev *indio_dev)
 {
@@ -488,6 +535,29 @@ static const struct iio_backend_info adi_axi_adc_generic = {
        .ops = &adi_axi_adc_ops,
 };
 
+static const struct iio_backend_ops adi_ad485x_ops = {
+       .enable = axi_adc_enable,
+       .disable = axi_adc_disable,
+       .data_format_set = axi_adc_data_format_set,
+       .chan_enable = axi_adc_chan_enable,
+       .chan_disable = axi_adc_chan_disable,
+       .request_buffer = axi_adc_request_buffer,
+       .free_buffer = axi_adc_free_buffer,
+       .data_sample_trigger = axi_adc_data_sample_trigger,
+       .iodelay_set = axi_adc_iodelays_set,
+       .chan_status = axi_adc_chan_status,
+       .interface_type_get = axi_adc_interface_type_get,
+       .data_size_set = axi_adc_ad485x_data_size_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),
+};
+
+static const struct iio_backend_info axi_ad485x = {
+       .name = "axi-ad485x",
+       .ops = &adi_ad485x_ops,
+};
+
 static int adi_axi_adc_probe(struct platform_device *pdev)
 {
        struct adi_axi_adc_state *st;
@@ -545,7 +615,7 @@ static int adi_axi_adc_probe(struct platform_device *pdev)
                return -ENODEV;
        }
 
-       ret = devm_iio_backend_register(&pdev->dev, &adi_axi_adc_generic, st);
+       ret = devm_iio_backend_register(&pdev->dev, st->info->backend_info, st);
        if (ret)
                return dev_err_probe(&pdev->dev, ret,
                                     "failed to register iio backend\n");
@@ -585,6 +655,11 @@ static const struct axi_adc_info adc_generic = {
        .backend_info = &adi_axi_adc_generic,
 };
 
+static const struct axi_adc_info adi_axi_ad485x = {
+       .version = ADI_AXI_PCORE_VER(10, 0, 'a'),
+       .backend_info = &axi_ad485x,
+};
+
 static const struct ad7606_platform_data ad7606_pdata = {
        .bus_reg_read = ad7606_bus_reg_read,
        .bus_reg_write = ad7606_bus_reg_write,
@@ -601,6 +676,7 @@ static const struct axi_adc_info adc_ad7606 = {
 /* Match table for of_platform binding */
 static const struct of_device_id adi_axi_adc_of_match[] = {
        { .compatible = "adi,axi-adc-10.0.a", .data = &adc_generic },
+       { .compatible = "adi,axi-ad485x", .data = &adi_axi_ad485x },
        { .compatible = "adi,axi-ad7606x", .data = &adc_ad7606 },
        { /* end of list */ }
 };