diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c index 5b19a88412a6..d855a605eab6 100644 --- a/drivers/iio/adc/stm32-dfsdm-adc.c +++ b/drivers/iio/adc/stm32-dfsdm-adc.c @@ -196,7 +196,7 @@ static int stm32_dfsdm_compute_osrs(struct stm32_dfsdm_filter *fl, int bits, shift; unsigned int m = 1; /* multiplication factor */ unsigned int p = fl->ford; /* filter order (ford) */ - struct stm32_dfsdm_filter_osr *flo = &fl->flo; + struct stm32_dfsdm_filter_osr *flo = &fl->flo[fast]; pr_debug("%s: Requested oversampling: %d\n", __func__, oversamp); /* @@ -217,7 +217,6 @@ static int stm32_dfsdm_compute_osrs(struct stm32_dfsdm_filter *fl, * Look for filter and integrator oversampling ratios which allows * to maximize data output resolution. */ - flo->res = 0; for (fosr = 1; fosr <= DFSDM_MAX_FL_OVERSAMPLING; fosr++) { for (iosr = 1; iosr <= DFSDM_MAX_INT_OVERSAMPLING; iosr++) { if (fast) @@ -309,6 +308,28 @@ static int stm32_dfsdm_compute_osrs(struct stm32_dfsdm_filter *fl, return 0; } +static int stm32_dfsdm_compute_all_osrs(struct iio_dev *indio_dev, + unsigned int oversamp) +{ + struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); + struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id]; + int ret0, ret1; + + memset(&fl->flo[0], 0, sizeof(fl->flo[0])); + memset(&fl->flo[1], 0, sizeof(fl->flo[1])); + + ret0 = stm32_dfsdm_compute_osrs(fl, 0, oversamp); + ret1 = stm32_dfsdm_compute_osrs(fl, 1, oversamp); + if (ret0 < 0 && ret1 < 0) { + dev_err(&indio_dev->dev, + "Filter parameters not found: errors %d/%d\n", + ret0, ret1); + return -EINVAL; + } + + return 0; +} + static int stm32_dfsdm_start_channel(struct stm32_dfsdm_adc *adc) { struct iio_dev *indio_dev = iio_priv_to_dev(adc); @@ -433,11 +454,25 @@ static int stm32_dfsdm_channels_configure(struct stm32_dfsdm_adc *adc, struct iio_dev *indio_dev = iio_priv_to_dev(adc); struct regmap *regmap = adc->dfsdm->regmap; struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[fl_id]; - struct stm32_dfsdm_filter_osr *flo = &fl->flo; + struct stm32_dfsdm_filter_osr *flo = &fl->flo[0]; const struct iio_chan_spec *chan; unsigned int bit; int ret; + fl->fast = 0; + + /* + * In continuous mode, use fast mode configuration, + * if it provides a better resolution. + */ + if (adc->nconv == 1 && !trig && + (indio_dev->currentmode & INDIO_BUFFER_SOFTWARE)) { + if (fl->flo[1].res >= fl->flo[0].res) { + fl->fast = 1; + flo = &fl->flo[1]; + } + } + if (!flo->res) return -EINVAL; @@ -463,7 +498,7 @@ static int stm32_dfsdm_filter_configure(struct stm32_dfsdm_adc *adc, struct iio_dev *indio_dev = iio_priv_to_dev(adc); struct regmap *regmap = adc->dfsdm->regmap; struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[fl_id]; - struct stm32_dfsdm_filter_osr *flo = &fl->flo; + struct stm32_dfsdm_filter_osr *flo = &fl->flo[fl->fast]; u32 cr1; const struct iio_chan_spec *chan; unsigned int bit, jchg = 0; @@ -490,6 +525,12 @@ static int stm32_dfsdm_filter_configure(struct stm32_dfsdm_adc *adc, if (ret) return ret; + ret = regmap_update_bits(regmap, DFSDM_CR1(fl_id), + DFSDM_CR1_FAST_MASK, + DFSDM_CR1_FAST(fl->fast)); + if (ret) + return ret; + /* * DFSDM modes configuration W.R.T audio/iio type modes * ---------------------------------------------------------------- @@ -636,7 +677,6 @@ static int dfsdm_adc_set_samp_freq(struct iio_dev *indio_dev, unsigned int spi_freq) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); - struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id]; unsigned int oversamp; int ret; @@ -646,11 +686,10 @@ static int dfsdm_adc_set_samp_freq(struct iio_dev *indio_dev, "Rate not accurate. requested (%u), actual (%u)\n", sample_freq, spi_freq / oversamp); - ret = stm32_dfsdm_compute_osrs(fl, 0, oversamp); - if (ret < 0) { - dev_err(&indio_dev->dev, "No filter parameters that match!\n"); + ret = stm32_dfsdm_compute_all_osrs(indio_dev, oversamp); + if (ret < 0) return ret; - } + adc->sample_freq = spi_freq / oversamp; adc->oversamp = oversamp; @@ -783,7 +822,7 @@ static inline void stm32_dfsdm_process_data(struct stm32_dfsdm_adc *adc, s32 *buffer) { struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id]; - struct stm32_dfsdm_filter_osr *flo = &fl->flo; + struct stm32_dfsdm_filter_osr *flo = &fl->flo[fl->fast]; unsigned int i = adc->nconv; s32 *ptr = buffer; @@ -1171,7 +1210,6 @@ static int stm32_dfsdm_write_raw(struct iio_dev *indio_dev, int val, int val2, long mask) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); - struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id]; struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[chan->channel]; unsigned int spi_freq; int ret = -EINVAL; @@ -1181,7 +1219,7 @@ static int stm32_dfsdm_write_raw(struct iio_dev *indio_dev, ret = iio_device_claim_direct_mode(indio_dev); if (ret) return ret; - ret = stm32_dfsdm_compute_osrs(fl, 0, val); + ret = stm32_dfsdm_compute_all_osrs(indio_dev, val); if (!ret) adc->oversamp = val; iio_device_release_direct_mode(indio_dev); @@ -1430,8 +1468,7 @@ static int stm32_dfsdm_adc_init(struct iio_dev *indio_dev) int ret, chan_idx; adc->oversamp = DFSDM_DEFAULT_OVERSAMPLING; - ret = stm32_dfsdm_compute_osrs(&adc->dfsdm->fl_list[adc->fl_id], 0, - adc->oversamp); + ret = stm32_dfsdm_compute_all_osrs(indio_dev, adc->oversamp); if (ret < 0) return ret; diff --git a/drivers/iio/adc/stm32-dfsdm.h b/drivers/iio/adc/stm32-dfsdm.h index 18b06ee6ed7b..5dbdae4ed881 100644 --- a/drivers/iio/adc/stm32-dfsdm.h +++ b/drivers/iio/adc/stm32-dfsdm.h @@ -263,13 +263,13 @@ struct stm32_dfsdm_filter_osr { /** * struct stm32_dfsdm_filter - structure relative to stm32 FDSDM filter * @ford: filter order - * @flo: filter oversampling structure + * @flo: filter oversampling data table indexed by fast mode flag * @sync_mode: filter synchronized with filter 0 * @fast: filter fast mode */ struct stm32_dfsdm_filter { enum stm32_dfsdm_sinc_order ford; - struct stm32_dfsdm_filter_osr flo; + struct stm32_dfsdm_filter_osr flo[2]; unsigned int sync_mode; unsigned int fast; };