[RFC PATCH 5/7] iio: adc: sd_adc_modulator: change to iio backend device

From: Olivier Moysan
Date: Fri Jun 23 2023 - 10:13:09 EST


Register the SD modulator as an IIO backend device instead of
a standard IIO device.

Signed-off-by: Olivier Moysan <olivier.moysan@xxxxxxxxxxx>
---
drivers/iio/adc/sd_adc_modulator.c | 65 ++++++++++++++++++++----------
1 file changed, 44 insertions(+), 21 deletions(-)

diff --git a/drivers/iio/adc/sd_adc_modulator.c b/drivers/iio/adc/sd_adc_modulator.c
index 327cc2097f6c..61246a52dc79 100644
--- a/drivers/iio/adc/sd_adc_modulator.c
+++ b/drivers/iio/adc/sd_adc_modulator.c
@@ -7,42 +7,65 @@
*/

#include <linux/iio/iio.h>
+#include <linux/iio/backend.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/platform_device.h>

-static const struct iio_info iio_sd_mod_iio_info;
+struct iio_sd_mod_priv {
+};

-static const struct iio_chan_spec iio_sd_mod_ch = {
- .type = IIO_VOLTAGE,
- .indexed = 1,
- .scan_type = {
- .sign = 'u',
- .realbits = 1,
- .shift = 0,
- },
+static int sd_mod_enable(struct iio_backend *backend)
+{
+ struct iio_sd_mod_priv *priv = backend->priv;
+
+ /* PM resume */
+
+ return 0;
+};
+
+static int sd_mod_disable(struct iio_backend *backend)
+{
+ struct iio_sd_mod_priv *priv = backend->priv;
+
+ /* PM suspend */
+
+ return 0;
+};
+
+static int sd_mod_read(struct iio_backend *backend, int *val, int *val2, long mask)
+{
+ struct iio_sd_mod_priv *priv = backend->priv;
+
+ switch (mask) {
+ /* Process channel info */
+ }
+
+ return -EINVAL;
+};
+
+static const struct iio_backend_ops sd_mod_ops = {
+ .enable = sd_mod_enable,
+ .disable = sd_mod_disable,
+ .read_raw = sd_mod_read,
};

static int iio_sd_mod_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
- struct iio_dev *iio;
-
- iio = devm_iio_device_alloc(dev, 0);
- if (!iio)
- return -ENOMEM;
+ struct iio_backend *backend;
+ struct iio_sd_mod_priv *priv;
+ int ret;

- iio->name = dev_name(dev);
- iio->info = &iio_sd_mod_iio_info;
- iio->modes = INDIO_BUFFER_HARDWARE;
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);

- iio->num_channels = 1;
- iio->channels = &iio_sd_mod_ch;
+ backend = iio_backend_alloc(dev);

- platform_set_drvdata(pdev, iio);
+ backend->priv = priv;
+ backend->ops = &sd_mod_ops;

- return devm_iio_device_register(&pdev->dev, iio);
+ return iio_backend_register(backend);
}

static const struct of_device_id sd_adc_of_match[] = {
--
2.25.1