This series brings fixes to STM32 DFSDM ADC driver.
Fabrice Gasnier (2):
iio: adc: stm32-dfsdm: fix successive oversampling settings
iio: adc: stm32-dfsdm: fix sample rate for div2 spi clock
drivers/iio/adc/stm32-dfsdm-adc.c | 17 ++++++++++++++---
1 file changed, 14 insertions(+), 3 deletions(-)
--
1.9.1
When doing successive oversampling settings, it may fail to update filter
parameters silently:
- First time oversampling is being set, it will be successful, as fl->res
is 0 initially.
- Next attempts with various oversamp value may return 0 (success), but
keep previous filter parameters, due to 'res' never reaches above or
equal current 'fl->res'.
This is particularly true when setting sampling frequency (that relies on
oversamp). Typical failure without error:
- run 1st test @16kHz samp freq will succeed
- run new test @8kHz will succeed as well
- run new test @16kHz (again): sample rate will remain 8kHz without error
Fixes: e2e6771c6462 ("IIO: ADC: add STM32 DFSDM sigma delta ADC support")
Signed-off-by: Fabrice Gasnier <[email protected]>
---
drivers/iio/adc/stm32-dfsdm-adc.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c
index 01422d1..dc911b6 100644
--- a/drivers/iio/adc/stm32-dfsdm-adc.c
+++ b/drivers/iio/adc/stm32-dfsdm-adc.c
@@ -144,6 +144,7 @@ static int stm32_dfsdm_set_osrs(struct stm32_dfsdm_filter *fl,
* Leave as soon as if exact resolution if reached.
* Otherwise the higher resolution below 32 bits is kept.
*/
+ fl->res = 0;
for (fosr = 1; fosr <= DFSDM_MAX_FL_OVERSAMPLING; fosr++) {
for (iosr = 1; iosr <= DFSDM_MAX_INT_OVERSAMPLING; iosr++) {
if (fast)
@@ -193,7 +194,7 @@ static int stm32_dfsdm_set_osrs(struct stm32_dfsdm_filter *fl,
}
}
- if (!fl->fosr)
+ if (!fl->res)
return -EINVAL;
return 0;
--
1.9.1
When channel clk source is set to "CLKOUT_F" or "CLKOUT_R" (e.g. div2),
sample rate is currently set to half the requested value.
Fixes: eca949800d2d ("IIO: ADC: add stm32 DFSDM support for PDM
microphone")
Signed-off-by: Fabrice Gasnier <[email protected]>
---
drivers/iio/adc/stm32-dfsdm-adc.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c
index dc911b6..b28a716 100644
--- a/drivers/iio/adc/stm32-dfsdm-adc.c
+++ b/drivers/iio/adc/stm32-dfsdm-adc.c
@@ -771,7 +771,7 @@ static int stm32_dfsdm_write_raw(struct iio_dev *indio_dev,
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 = adc->spi_freq;
+ unsigned int spi_freq;
int ret = -EINVAL;
switch (mask) {
@@ -785,8 +785,18 @@ static int stm32_dfsdm_write_raw(struct iio_dev *indio_dev,
case IIO_CHAN_INFO_SAMP_FREQ:
if (!val)
return -EINVAL;
- if (ch->src != DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL)
+
+ 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;
+ }
if (spi_freq % val)
dev_warn(&indio_dev->dev,
--
1.9.1
Hello,
For the series:
Acked-by: Arnaud Pouliquen <[email protected]>
Thanks,
Arnaud
On 03/13/2018 03:23 PM, Fabrice Gasnier wrote:
> This series brings fixes to STM32 DFSDM ADC driver.
>
> Fabrice Gasnier (2):
> iio: adc: stm32-dfsdm: fix successive oversampling settings
> iio: adc: stm32-dfsdm: fix sample rate for div2 spi clock
>
> drivers/iio/adc/stm32-dfsdm-adc.c | 17 ++++++++++++++---
> 1 file changed, 14 insertions(+), 3 deletions(-)
>
On Fri, 16 Mar 2018 10:10:09 +0100
Arnaud Pouliquen <[email protected]> wrote:
> Hello,
>
> For the series:
> Acked-by: Arnaud Pouliquen <[email protected]>
Both applied and marked for stable (as I'm not sure exactly when this will hit
mainline and it may be after the next merge window)
Thanks,
Jonathan
>
> Thanks,
> Arnaud
>
> On 03/13/2018 03:23 PM, Fabrice Gasnier wrote:
> > This series brings fixes to STM32 DFSDM ADC driver.
> >
> > Fabrice Gasnier (2):
> > iio: adc: stm32-dfsdm: fix successive oversampling settings
> > iio: adc: stm32-dfsdm: fix sample rate for div2 spi clock
> >
> > drivers/iio/adc/stm32-dfsdm-adc.c | 17 ++++++++++++++---
> > 1 file changed, 14 insertions(+), 3 deletions(-)
> >