iio: adc: ad7780: remove IIO_CHAN_INFO_SAMP_FREQ support

The `ad7780` driver does not implement setting/getting the sampling
frequency.
For the ad7780/ad7781 devices, the control is done via an external pin,
and the ad7170/ad7171 devices have a fixed sampling rate (so, no control).

For these devices, and similar other that may be added later on,
a AD_SD_CHANNEL_NO_SAMPLE_FREQ() macro has been added, which doesn't set
the IIO_CHAN_INFO_SAMP_FREQ flag.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/staging/iio/adc/ad7780.c

@@ -128,7 +128,7 @@ static const struct ad_sigma_delta_info ad7780_sigma_delta_info = {
 };
 
 #define AD7780_CHANNEL(bits, wordsize) \
-	AD_SD_CHANNEL(1, 0, 0, bits, 32, wordsize - bits)
+	AD_SD_CHANNEL_NO_SAMP_FREQ(1, 0, 0, bits, 32, wordsize - bits)
 
 static const struct ad7780_chip_info ad7780_chip_info_tbl[] = {
 	[ID_AD7170] = {

include/linux/iio/adc/ad_sigma_delta.h

@@ -127,7 +127,7 @@ void ad_sd_cleanup_buffer_and_trigger(struct iio_dev *indio_dev);
 int ad_sd_validate_trigger(struct iio_dev *indio_dev, struct iio_trigger *trig);
 
 #define __AD_SD_CHANNEL(_si, _channel1, _channel2, _address, _bits, \
-	_storagebits, _shift, _extend_name, _type) \
+	_storagebits, _shift, _extend_name, _type, _mask_all) \
 	{ \
 		.type = (_type), \
 		.differential = (_channel2 == -1 ? 0 : 1), \
@@ -139,7 +139,7 @@ int ad_sd_validate_trigger(struct iio_dev *indio_dev, struct iio_trigger *trig);
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
 			BIT(IIO_CHAN_INFO_OFFSET), \
 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
-		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+		.info_mask_shared_by_all = _mask_all, \
 		.scan_index = (_si), \
 		.scan_type = { \
 			.sign = 'u', \
@@ -153,25 +153,35 @@ int ad_sd_validate_trigger(struct iio_dev *indio_dev, struct iio_trigger *trig);
 #define AD_SD_DIFF_CHANNEL(_si, _channel1, _channel2, _address, _bits, \
 	_storagebits, _shift) \
 	__AD_SD_CHANNEL(_si, _channel1, _channel2, _address, _bits, \
-		_storagebits, _shift, NULL, IIO_VOLTAGE)
+		_storagebits, _shift, NULL, IIO_VOLTAGE, \
+		BIT(IIO_CHAN_INFO_SAMP_FREQ))
 
 #define AD_SD_SHORTED_CHANNEL(_si, _channel, _address, _bits, \
 	_storagebits, _shift) \
 	__AD_SD_CHANNEL(_si, _channel, _channel, _address, _bits, \
-		_storagebits, _shift, "shorted", IIO_VOLTAGE)
+		_storagebits, _shift, "shorted", IIO_VOLTAGE, \
+		BIT(IIO_CHAN_INFO_SAMP_FREQ))
 
 #define AD_SD_CHANNEL(_si, _channel, _address, _bits, \
 	_storagebits, _shift) \
 	__AD_SD_CHANNEL(_si, _channel, -1, _address, _bits, \
-		_storagebits, _shift, NULL, IIO_VOLTAGE)
+		_storagebits, _shift, NULL, IIO_VOLTAGE, \
+		 BIT(IIO_CHAN_INFO_SAMP_FREQ))
+
+#define AD_SD_CHANNEL_NO_SAMP_FREQ(_si, _channel, _address, _bits, \
+	_storagebits, _shift) \
+	__AD_SD_CHANNEL(_si, _channel, -1, _address, _bits, \
+		_storagebits, _shift, NULL, IIO_VOLTAGE, 0)
 
 #define AD_SD_TEMP_CHANNEL(_si, _address, _bits, _storagebits, _shift) \
 	__AD_SD_CHANNEL(_si, 0, -1, _address, _bits, \
-		_storagebits, _shift, NULL, IIO_TEMP)
+		_storagebits, _shift, NULL, IIO_TEMP, \
+		BIT(IIO_CHAN_INFO_SAMP_FREQ))
 
 #define AD_SD_SUPPLY_CHANNEL(_si, _channel, _address, _bits, _storagebits, \
 	_shift) \
 	__AD_SD_CHANNEL(_si, _channel, -1, _address, _bits, \
-		_storagebits, _shift, "supply", IIO_VOLTAGE)
+		_storagebits, _shift, "supply", IIO_VOLTAGE, \
+		BIT(IIO_CHAN_INFO_SAMP_FREQ))
 
 #endif