From f81ec5bf0cab29693980abbc983d0971e0efb0ea Mon Sep 17 00:00:00 2001 From: Olivier Moysan Date: Wed, 27 Nov 2019 14:10:08 +0100 Subject: iio: adc: stm32-dfsdm: adapt sampling rate to oversampling ratio Update sampling rate when oversampling ratio is changed through the IIO ABI. Signed-off-by: Olivier Moysan Acked-by: Fabrice Gasnier Signed-off-by: Jonathan Cameron --- drivers/iio/adc/stm32-dfsdm-adc.c | 32 +++++++++++++++++++------------- 1 file changed, 19 insertions(+), 13 deletions(-) (limited to 'drivers/iio') diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c index 1c9b05d11dc5..2aad2cda6943 100644 --- a/drivers/iio/adc/stm32-dfsdm-adc.c +++ b/drivers/iio/adc/stm32-dfsdm-adc.c @@ -1221,14 +1221,32 @@ static int stm32_dfsdm_write_raw(struct iio_dev *indio_dev, unsigned int spi_freq; int ret = -EINVAL; + switch (ch->src) { + case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL: + spi_freq = adc->dfsdm->spi_master_freq; + break; + case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_FALLING: + case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_RISING: + spi_freq = adc->dfsdm->spi_master_freq / 2; + break; + default: + spi_freq = adc->spi_freq; + } + switch (mask) { case IIO_CHAN_INFO_OVERSAMPLING_RATIO: ret = iio_device_claim_direct_mode(indio_dev); if (ret) return ret; + ret = stm32_dfsdm_compute_all_osrs(indio_dev, val); - if (!ret) + if (!ret) { + dev_dbg(&indio_dev->dev, + "Sampling rate changed from (%u) to (%u)\n", + adc->sample_freq, spi_freq / val); adc->oversamp = val; + adc->sample_freq = spi_freq / val; + } iio_device_release_direct_mode(indio_dev); return ret; @@ -1240,18 +1258,6 @@ static int stm32_dfsdm_write_raw(struct iio_dev *indio_dev, if (ret) return ret; - switch (ch->src) { - case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL: - spi_freq = adc->dfsdm->spi_master_freq; - break; - case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_FALLING: - case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_RISING: - spi_freq = adc->dfsdm->spi_master_freq / 2; - break; - default: - spi_freq = adc->spi_freq; - } - ret = dfsdm_adc_set_samp_freq(indio_dev, val, spi_freq); iio_device_release_direct_mode(indio_dev); return ret; -- cgit