Commit 7394a155 authored by Nuno Sa's avatar Nuno Sa Committed by Jonathan Cameron
Browse files

iio: adc: ad9467: support multiple channels calibration 



The calibration process mixes the support for calibrating multiple
channels with only having one channel. Some paths do have 'num_channels'
into account while others don't.

As of now, the driver only supports devices with one channel so the
above is not really a problem. That said, we'll add support for devices
with more than one channel, hence let's properly make the calibration
process to work with it.

Signed-off-by: default avatarNuno Sa <nuno.sa@analog.com>
Link: https://patch.msgid.link/20240704-dev-iio-ad9467-new-devs-v1-1-f1adfee921f7@analog.com


Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent 1de9c3c7

drivers/iio/adc/ad9467.c

+75 −40
Original line number Diff line number Diff line
@@ -352,6 +352,34 @@ static int ad9467_outputmode_set(struct ad9467_state *st, unsigned int mode) 
				AN877_ADC_TRANSFER_SYNC);

}



static int ad9467_testmode_set(struct ad9467_state *st, unsigned int chan,

			       unsigned int test_mode)

{

	int ret;



	if (st->info->num_channels > 1) {

		/* so that the test mode is only applied to one channel */

		ret = ad9467_spi_write(st, AN877_ADC_REG_CHAN_INDEX, BIT(chan));

		if (ret)

			return ret;

	}



	ret = ad9467_spi_write(st, AN877_ADC_REG_TEST_IO, test_mode);

	if (ret)

		return ret;



	if (st->info->num_channels > 1) {

		/* go to default state where all channels get write commands */

		ret = ad9467_spi_write(st, AN877_ADC_REG_CHAN_INDEX,

				       GENMASK(st->info->num_channels - 1, 0));

		if (ret)

			return ret;

	}



	return ad9467_spi_write(st, AN877_ADC_REG_TRANSFER,

				AN877_ADC_TRANSFER_SYNC);

}



static int ad9647_calibrate_prepare(struct ad9467_state *st)

{

	struct iio_backend_data_fmt data = {
@@ -360,32 +388,30 @@ static int ad9647_calibrate_prepare(struct ad9467_state *st) 
	unsigned int c;

	int ret;



	ret = ad9467_spi_write(st, AN877_ADC_REG_TEST_IO,

			       AN877_ADC_TESTMODE_PN9_SEQ);

	ret = ad9467_outputmode_set(st, st->info->default_output_mode);

	if (ret)

		return ret;



	ret = ad9467_spi_write(st, AN877_ADC_REG_TRANSFER,

			       AN877_ADC_TRANSFER_SYNC);

	for (c = 0; c < st->info->num_channels; c++) {

		ret = ad9467_testmode_set(st, c, AN877_ADC_TESTMODE_PN9_SEQ);

		if (ret)

			return ret;



	ret = ad9467_outputmode_set(st, st->info->default_output_mode);

		ret = iio_backend_data_format_set(st->back, c, &data);

		if (ret)

			return ret;



	for (c = 0; c < st->info->num_channels; c++) {

		ret = iio_backend_data_format_set(st->back, c, &data);

		ret = iio_backend_test_pattern_set(st->back, c,

						   IIO_BACKEND_ADI_PRBS_9A);

		if (ret)

			return ret;

	}



	ret = iio_backend_test_pattern_set(st->back, 0,

					   IIO_BACKEND_ADI_PRBS_9A);

		ret = iio_backend_chan_enable(st->back, c);

		if (ret)

			return ret;

	}



	return iio_backend_chan_enable(st->back, 0);

	return 0;

}



static int ad9647_calibrate_polarity_set(struct ad9467_state *st,
@@ -468,38 +494,32 @@ static int ad9647_calibrate_stop(struct ad9467_state *st) 
	unsigned int c, mode;

	int ret;



	ret = iio_backend_chan_disable(st->back, 0);

	for (c = 0; c < st->info->num_channels; c++) {

		ret = iio_backend_chan_disable(st->back, c);

		if (ret)

			return ret;



	ret = iio_backend_test_pattern_set(st->back, 0,

		ret = iio_backend_test_pattern_set(st->back, c,

						   IIO_BACKEND_NO_TEST_PATTERN);

		if (ret)

			return ret;



	for (c = 0; c < st->info->num_channels; c++) {

		ret = iio_backend_data_format_set(st->back, c, &data);

		if (ret)

			return ret;

	}



	mode = st->info->default_output_mode | AN877_ADC_OUTPUT_MODE_TWOS_COMPLEMENT;

	ret = ad9467_outputmode_set(st, mode);

	if (ret)

		return ret;



	ret = ad9467_spi_write(st, AN877_ADC_REG_TEST_IO,

			       AN877_ADC_TESTMODE_OFF);

		ret = ad9467_testmode_set(st, c, AN877_ADC_TESTMODE_OFF);

		if (ret)

			return ret;

	}



	return ad9467_spi_write(st, AN877_ADC_REG_TRANSFER,

			       AN877_ADC_TRANSFER_SYNC);

	mode = st->info->default_output_mode | AN877_ADC_OUTPUT_MODE_TWOS_COMPLEMENT;

	return ad9467_outputmode_set(st, mode);

}



static int ad9467_calibrate(struct ad9467_state *st)

{

	unsigned int point, val, inv_val, cnt, inv_cnt = 0;

	unsigned int point, val, inv_val, cnt, inv_cnt = 0, c;

	/*

	 * Half of the bitmap is for the inverted signal. The number of test

	 * points is the same though...
@@ -526,11 +546,26 @@ static int ad9467_calibrate(struct ad9467_state *st) 
		if (ret)

			return ret;



		ret = iio_backend_chan_status(st->back, 0, &stat);

		for (c = 0; c < st->info->num_channels; c++) {

			ret = iio_backend_chan_status(st->back, c, &stat);

			if (ret)

				return ret;



		__assign_bit(point + invert * test_points, st->calib_map, stat);

			/*

			 * A point is considered valid if all channels report no

			 * error. If one reports an error, then we consider the

			 * point as invalid and we can break the loop right away.

			 */

			if (stat) {

				dev_dbg(dev, "Invalid point(%u, inv:%u) for CH:%u\n",

					point, invert, c);

				break;

			}



			if (c == st->info->num_channels - 1)

				__clear_bit(point + invert * test_points,

					    st->calib_map);

		}

	}



	if (!invert) {