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-rw-r--r--drivers/iio/adc/stm32-dfsdm-adc.c65
-rw-r--r--drivers/iio/adc/stm32-dfsdm.h4
2 files changed, 53 insertions, 16 deletions
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;
};
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.